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  • Public defence: 2025-03-21 09:00 H:son Holmdahlsalen, Uppsala
    Lafta, Muataz
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Functional Pharmacology and Neuroscience.
    Identification of candidate biomarkers in neurological and psychiatric health2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Psychiatric and neurological diseases present substantial challenges in healthcare, affecting millions of individuals worldwide. Conditions such as depression, trigeminal neuralgia (TN), and narcolepsy have a profound impact on the quality of life for both patients and their families. The complex nature of these conditions necessitates the development of innovative diagnostic and treatment strategies. In recent years, the importance of biomarkers in understanding, diagnosing, and managing psychiatric and neurological diseases has emerged as a promising field of research. In the current thesis, five studies were conducted to identify candidate biomarkers in depression, TN, and narcolepsy. Study I validated depression-associated genetic variants in the UK Biobank (UKB) cohort, with transcriptome and DNA methylation analyses in independent datasets. Eight single nucleotide polymorphisms corresponding to six protein-coding genes (TNXB, NCAM1, LTBP3, BTN3A2, DAG1, FHIT) were strongly linked to depression. Study II analyzed 92 proteins in cerebrospinal fluid and serum from TN patients, compared with multiple sclerosis patients and controls. Several proteins, including SFRP1, FKBP5, and TBCB, were elevated in TN, suggesting their relevance in disease mechanisms. Study III examined protein levels in adolescents assessed for depression in the domestic Psychiatric Health in Adolescent Study (PSY cohort) in Sweden, with transcriptome validation in independent cohorts. Key findings highlighted protein and transcriptomic differences, particularly in PPP3R1, implicating the calcineurin pathway and prefrontal cortex in depression. Study IV explored genetic evidence in the UKB to validate the role of 17 proteins from previous studies in TN. Novel associations were identified with C8B (complement system) and MFGE8 (neuroinflammation regulation), highlighting their roles in TN pathology. Finally, Study V assessed protein biomarkers in narcolepsy using Swedish and Finnish cohorts, with transcriptome validation in an independent dataset. The identified candidate proteins were indicative of neural development involving survival, growth, and differentiation (UNC5C, VWC2, GFR-alpha-1, ADAM23), oxidative stress (HAGH), immune response (CLEC10A), and cell cycle regulation (ILKAP). Collectively, these studies identify potential biomarkers across these conditions, offering insights into their underlying mechanisms. The findings expand our understanding of psychiatric and neurological health and may inform future research and therapeutic strategies.

    List of papers
    1. Identification and validation of depression-associated genetic variants in the UK Biobank cohort with transcriptome and DNA methylation analyses in independent cohorts
    Open this publication in new window or tab >>Identification and validation of depression-associated genetic variants in the UK Biobank cohort with transcriptome and DNA methylation analyses in independent cohorts
    (English)Manuscript (preprint) (Other academic)
    National Category
    Medical and Health Sciences Medical Genetics and Genomics
    Research subject
    Psychiatry
    Identifiers
    urn:nbn:se:uu:diva-540072 (URN)
    Available from: 2024-10-09 Created: 2024-10-09 Last updated: 2025-02-10
    2. Exploring biomarkers in trigeminal neuralgia patients operated with microvascular decompression: A comparison with multiple sclerosis patients and non-neurological controls
    Open this publication in new window or tab >>Exploring biomarkers in trigeminal neuralgia patients operated with microvascular decompression: A comparison with multiple sclerosis patients and non-neurological controls
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    2024 (English)In: European Journal of Pain, ISSN 1090-3801, E-ISSN 1532-2149, Vol. 28, no 6, p. 929-942Article in journal (Refereed) Published
    Abstract [en]

    BACKGROUND: Trigeminal neuralgia (TN) is a severe facial pain condition often associated with a neurovascular conflict. However, neuroinflammation has also been implicated in TN, as it frequently co-occurs with multiple sclerosis (MS).

    METHODS: We analysed protein expression levels of TN patients compared to MS patients and controls. Proximity Extension Assay technology was used to analyse the levels of 92 proteins with the Multiplex Neuro-Exploratory panel provided by SciLifeLab, Uppsala, Sweden. Serum and CSF samples were collected from TN patients before (n = 33 and n = 27, respectively) and after (n = 28 and n = 8, respectively) microvascular decompression surgery. Additionally, we included samples from MS patients (n = 20) and controls (n = 20) for comparison.

    RESULTS: In both serum and CSF, several proteins were found increased in TN patients compared to either MS patients, controls, or both, including EIF4B, PTPN1, EREG, TBCB, PMVK, FKBP5, CD63, CRADD, BST2, CD302, CRIP2, CCL27, PPP3R1, WWP2, KLB, PLA2G10, TDGF1, SMOC1, RBKS, LTBP3, CLSTN1, NXPH1, SFRP1, HMOX2, and GGT5. The overall expression of the 92 proteins in postoperative TN samples seems to shift towards the levels of MS patients and controls in both serum and CSF, as compared to preoperative samples. Interestingly, there was no difference in protein levels between MS patients and controls.

    CONCLUSIONS: We conclude that TN patients showed increased serum and CSF levels of specific proteins and that successful surgery normalizes these protein levels, highlighting its potential as an effective treatment. However, the similarity between MS and controls challenges the idea of shared pathophysiology with TN, suggesting distinct underlying mechanisms in these conditions.

    SIGNIFICANCE: This study advances our understanding of trigeminal neuralgia (TN) and its association with multiple sclerosis (MS). By analysing 92 protein biomarkers, we identified distinctive molecular profiles in TN patients, shedding light on potential pathophysiological mechanisms. The observation that successful surgery normalizes many protein levels suggests a promising avenue for TN treatment. Furthermore, the contrasting protein patterns between TN and MS challenge prevailing assumptions of similarity between the two conditions and point to distinct pathophysiological mechanisms.

    Place, publisher, year, edition, pages
    John Wiley & Sons, 2024
    National Category
    Neurology
    Identifiers
    urn:nbn:se:uu:diva-519432 (URN)10.1002/ejp.2231 (DOI)001133731000001 ()38158702 (PubMedID)
    Available from: 2024-01-08 Created: 2024-01-08 Last updated: 2025-01-25Bibliographically approved
    3. Depression proteomic profiling in adolescents with transcriptome analyses in independent cohorts
    Open this publication in new window or tab >>Depression proteomic profiling in adolescents with transcriptome analyses in independent cohorts
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    2024 (English)In: Frontiers in Psychiatry, E-ISSN 1664-0640, Vol. 15, article id 1372106Article in journal (Refereed) Published
    Abstract [en]

    Introduction Depression is a major global burden with unclear pathophysiology and poor treatment outcomes. Diagnosis of depression continues to rely primarily on behavioral rather than biological methods. Investigating tools that might aid in diagnosing and treating early-onset depression is essential for improving the prognosis of the disease course. While there is increasing evidence of possible biomarkers in adult depression, studies investigating this subject in adolescents are lacking.Methods In the current study, we analyzed protein levels in 461 adolescents assessed for depression using the Development and Well-Being Assessment (DAWBA) questionnaire as part of the domestic Psychiatric Health in Adolescent Study conducted in Uppsala, Sweden. We used the Proseek Multiplex Neuro Exploratory panel with Proximity Extension Assay technology provided by Olink Bioscience, followed by transcriptome analyses for the genes corresponding to the significant proteins, using four publicly available cohorts.Results We identified a total of seven proteins showing different levels between DAWBA risk groups at nominal significance, including RBKS, CRADD, ASGR1, HMOX2, PPP3R1, CD63, and PMVK. Transcriptomic analyses for these genes showed nominally significant replication of PPP3R1 in two of four cohorts including whole blood and prefrontal cortex, while ASGR1 and CD63 were replicated in only one cohort.Discussion Our study on adolescent depression revealed protein-level and transcriptomic differences, particularly in PPP3R1, pointing to the involvement of the calcineurin pathway in depression. Our findings regarding PPP3R1 also support the role of the prefrontal cortex in depression and reinforce the significance of investigating prefrontal cortex-related mechanisms in depression.

    Place, publisher, year, edition, pages
    Frontiers Media S.A., 2024
    Keywords
    depression, proteome, transcriptome, adolescents, psychiatry
    National Category
    Psychiatry
    Identifiers
    urn:nbn:se:uu:diva-531087 (URN)10.3389/fpsyt.2024.1372106 (DOI)001233868300001 ()38812487 (PubMedID)
    Available from: 2024-06-13 Created: 2024-06-13 Last updated: 2025-01-25Bibliographically approved
    4. Genomic Validation in the UK Biobank Cohort Suggests a Role of C8B and MFG-E8 in the Pathogenesis of Trigeminal Neuralgia
    Open this publication in new window or tab >>Genomic Validation in the UK Biobank Cohort Suggests a Role of C8B and MFG-E8 in the Pathogenesis of Trigeminal Neuralgia
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    2024 (English)In: Journal of Molecular Neuroscience, ISSN 0895-8696, E-ISSN 1559-1166, Vol. 74, no 4, article id 91Article in journal (Refereed) Published
    Abstract [en]

    Trigeminal neuralgia (TN) is a severe facial pain disease of uncertain pathophysiology and unclear genetic background. Although recent research has reported a more important role of genetic factors in TN pathogenesis, few candidate genes have been proposed to date. The present study aimed to identify independent genetic variants in the protein-coding genes associated with TN. We focused on genes previously linked to TN based on the results of four proteomic studies conducted by our research team. The goal was to validate these findings on the genetic level to enhance our understanding of the role of genetics in TN. The study is based on the participants from UK Biobank cohort. Following quality control, 175 independent single nucleotide polymorphisms (SNPs) in 17 genes were selected. The study sample comprised of diagnosed TN cases (N = 555) and randomly matched controls (N = 6245) based on specific criteria. Two SNPs corresponding to C8B rs706484 [odds ratio (OR) (95% confidence interval (CI)): 1.357 (1.158–1.590); p: 0.00016] and MFG-E8 rs2015495 [OR (95% CI): 1.313 (1.134–1.521); p: 0.00028] showed significant positive association with TN, indicating a positive effect of the SNP alleles on gene expression and disease risk. Interestingly, both SNPs are Expression Quantitative Trait Loci (eQTLs), and are associated with changes in the expression activity of their corresponding gene. Our findings suggest novel genetic associations between C8B, a key component of the complement system, and MFG-E8, which plays a role in regulating neuroinflammation, in relation to TN. The identified genetic variations may help explain why some individuals develop TN while others do not, indicating a potential genetic predisposition to the condition.

    Place, publisher, year, edition, pages
    Springer, 2024
    Keywords
    Trigeminal neuralgia, Proteome, Independent genetic variants, UK Biobank
    National Category
    Medical Genetics and Genomics Neurology Genetics and Genomics
    Identifiers
    urn:nbn:se:uu:diva-540375 (URN)10.1007/s12031-024-02263-x (DOI)001325838600001 ()39361088 (PubMedID)
    Funder
    Uppsala UniversitySwedish Research CouncilThe Swedish Brain Foundation
    Note

    De två sista författarna delar sistaförfattarskapet

    Available from: 2024-10-17 Created: 2024-10-17 Last updated: 2025-02-10Bibliographically approved
    5. Exploratory Assessment of Candidate Biomarkers in Narcolepsy: Identification and Validation in H1N1-Vaccinated Cohorts at the Proteome and Transcriptome Levels
    Open this publication in new window or tab >>Exploratory Assessment of Candidate Biomarkers in Narcolepsy: Identification and Validation in H1N1-Vaccinated Cohorts at the Proteome and Transcriptome Levels
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Neurosciences
    Identifiers
    urn:nbn:se:uu:diva-548489 (URN)
    Available from: 2025-01-25 Created: 2025-01-25 Last updated: 2025-01-25
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  • Public defence: 2025-03-21 10:15 Hörsal 2, Ekonomikum, Uppsala
    Rönngren, Emma
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Informatics and Media. Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Institute for Russian and Eurasian Studies. Institute for Russian and Eurasian Studies.
    Making Sense of Russian Strategic Narratives: Affect and Reception Among Young Russian Speakers in Latvia2025Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This dissertation explores the reception of Russian strategic narratives among Russian-speaking youth in Latvia. Bringing together media and communication studies, international relations and Baltic studies, it approaches narrative persuasion and its reception from a cultural perspective.

    The primary data for this study consist of 12 focus groups and 13 individual follow-up interviews with 69 young Russian speakers aged 18–30 in Riga, Daugavpils and Liepāja between 2021 and 2022. Drawing on the conceptual framework of strategic narratives, such narratives pertaining to history, freedom of speech and language were identified and analysed in Russian foreign policy documents, press briefings and Sputnik Latvia media texts. The media ecology in which these narratives were projected and received were studied using thematic analysis, focusing on participants’ media use and perception of news as a social and cultural context for the reception of narratives. Using Carolyn Michelle’s reception model, participants’ sensemaking of these narratives was analysed on denotative and connotative levels of meaning.

    By adapting Michelle’s model, this study adds affect as a factor that influences the reception of narrative texts. It demonstrates that affect serves as a force that increases narrative persuasion, pushing participants to skip denotative levels of meaning and move directly to connotative levels. It is also a force that can push a reader into a mediated mode and become critical of the text because of its emotional content. Heightened or diminished affect facilitates shifts.

    Findings reveal that young Russian speakers in Latvia are a far from homogeneous group. Generally, they are neither critically opposing Russian strategic narratives nor uncritically taking them to heart. The reality is rather somewhere in between. As such, this research project brings nuance to a situation where censorship, ‘us versus them’ thinking, and polarisation are increasingly taking over public discourse.

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  • Public defence: 2025-03-21 10:15 Sal IX, Universitetshuset, Uppsala
    Langby, Martin
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Theology, Department of Theology, Ethics and Philosophy of Religion.
    Emancipation and Christian Feminism: A Critical Study in Ethics of Subjectivity, Vulnerability, and Relationality2025Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This study explores the emancipatory potential in different strands of contemporary Christian feminist theology. The study develops a comprehensive understanding of how subjectivity, vulnerability, and relationality intersect with and impact Christian feminist ethics, which seeks to counteract patriarchy and promote emancipation. This is operationalized by the research question: How do different understandings of subjectivity, vulnerability, and relationality relate to Christian feminist ethics and its emancipatory potential? To answer this, the author explores how subjectivity, vulnerability, and relationality are understood in three prominent models of contemporary Christian feminist ethics as devised by Susan Frank Parsons, Catharine Keller, and Denise M. Ackermann.

    The theoretical framework used to analyze the views of the three theologians draws primarily on the works of Judith Butler and Hille Haker. Additionally, Michel Foucault’s understanding of power is crucial to assessing different models’ emancipatory potential. The study challenges prevalent perspectives that are often found in Christianity, and seeks to move beyond such ideologies and practices that use Christian traditions to legitimize domination, especially of women.

    The author argues that a dialectical understanding of subjectivity, vulnerability, and relationality provides new critical resources for Christian feminist ethics. Ethics and theology are seen as mutually reinforcing; and it is argued that Christian feminism should embrace a self-reflexive stance that is devoid of triumphalism, and support a theology that does not promote or support domination of others.

    The author argues for a constructivist approach to gender, since it provides more nuanced resources for the critique of different forms of patriarchy if compared with essentialism, which risks reinforcing dualisms that could support hierarchical divisions. As a critique of the mind/body dualism devised after Descartes, the author argues for a dialectical approach to mind and body—an approach that challenges hierarchies and domination. Subjectivity is argued to be constituted relationally; and vulnerability, as an ontological condition of human existence, should be embraced rather than eliminated.

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  • Public defence: 2025-03-21 13:00 Lecture Hall IV, Uppsala
    Ageheim, Mårten
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Obstetrics and Reproductive Health Research.
    Fetal and postnatal growth following natural conception and IVF treatment2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Abnormal fetal growth is closely related to adverse short-term outcomes as well as negative long-term health consequences. Fetal growth restriction is a common pregnancy complication, and for the detection of fetuses small for gestational age, a reliable reference is vital. Increasing evidence supports that mode of conception has implications for growth. Fresh embryo transfer (ET) is associated with small for gestational age, and frozen ET with large for gestational age. The overall aim of this thesis was to describe optimal fetal growth, as well as pre-and postnatal growth after ART, trying to isolate the direct effects of ART from related factors.

    Study I was a prospective multicentre study aiming to construct updated population-based references for fetal growth for the Swedish population from a cohort of 583 low-risk pregnancies. Comparisons were also made with other relevant growth charts.

    In Study II, a population-based retrospective cohort study including 10 970 fresh ET, 6520 frozen ET, and 178 518 natural conception (NC) pregnancies, fetal growth after ART was explored with longitudinal statistics. Study III, a prospective longitudinal multicentre study of 82 fresh ET, 175 frozen ET and the 583 NC from Study I as reference, had similar aims. Fetuses after ART in general tended to be larger than NC in early pregnancy and thereafter growing at a slower rate than NC. This was more pronounced after fresh ET and at term mean fetal weight was lower than NC. Frozen ET remained heavier than NC in Study II but in Study III there were no significant differences.

    Study IV was a population-based retrospective cohort study of 517 fresh ET, 284 frozen ET and  17 214 NC, examining growth from birth to five years of age. At birth, children after fresh ET were smaller, and those after frozen ET were larger than NC. Most differences were attenuated by 18 months of age.

    The new references will in future studies be evaluated for the intended population. Our results support that there is a direct effect of ART on fetal growth. Although differences diminish with age, the differences in growth are known risk factors for future cardiometabolic disease.

    List of papers
    1. Swedish intrauterine growth reference ranges for estimated fetal weight
    Open this publication in new window or tab >>Swedish intrauterine growth reference ranges for estimated fetal weight
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    2021 (English)In: Scientific Reports, E-ISSN 2045-2322, Vol. 11, no 1, article id 12464Article in journal (Refereed) Published
    Abstract [en]

    Fetal growth restriction is a strong risk factor for perinatal morbidity and mortality. Reliable standards are indispensable, both to assess fetal growth and to evaluate birthweight and early postnatal growth in infants born preterm. The aim of this study was to create updated Swedish reference ranges for estimated fetal weight (EFW) from gestational week 12-42. This prospective longitudinal multicentre study included 583 women without known conditions causing aberrant fetal growth. Each woman was assigned a randomly selected protocol of five ultrasound scans from gestational week 12 + 3 to 41 + 6. Hadlock's 3rd formula was used to estimate fetal weight. A two-level hierarchical regression model was employed to calculate the expected median and variance, expressed in standard deviations and percentiles, for EFW. EFW was higher for males than females. The reference ranges were compared with the presently used Swedish, and international reference ranges. Our reference ranges had higher EFW than the presently used Swedish reference ranges from gestational week 33, and higher median, 2.5th and 97.5th percentiles from gestational week 24 compared with INTERGROWTH-21st. The new reference ranges can be used both for assessment of intrauterine fetal weight and growth, and early postnatal growth in children born preterm.

    Place, publisher, year, edition, pages
    Springer Nature, 2021
    Keywords
    perinatal, mortality, infants
    National Category
    Gynaecology, Obstetrics and Reproductive Medicine
    Identifiers
    urn:nbn:se:uu:diva-447847 (URN)10.1038/s41598-021-92032-2 (DOI)000696753700052 ()34127756 (PubMedID)
    Funder
    Insamlingsstiftelsen Födelsefonden - Perinatalmedicinska forskningsfonden i UppsalaGillbergska stiftelsenSwedish Society of Medicine
    Available from: 2021-06-30 Created: 2021-06-30 Last updated: 2025-02-11Bibliographically approved
    2. Fetal growth after fresh and frozen embryo transfer and natural conception: A population‐based register study
    Open this publication in new window or tab >>Fetal growth after fresh and frozen embryo transfer and natural conception: A population‐based register study
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    2024 (English)In: British Journal of Obstetrics and Gynecology, ISSN 1470-0328, E-ISSN 1471-0528, Vol. 131, no 9, p. 1229-1237Article in journal (Refereed) Published
    Abstract [en]

    Objective: To investigate fetal growth trajectories and risks of small and large for gestational age (SGA and LGA), and macrosomia in pregnancies after fresh and frozen embryo transfer (ET), and natural conception (NC).

    Design: Longitudinal population-based cohort study.

    Setting: Swedish national registers.

    Population: A total of 196 008 singleton pregnancies between 2013 and 2017.

    Methods: Of all singleton pregnancies resulting in live births in the Swedish Pregnancy Register, 10 970 fresh ET, 6520 frozen ET, and 178 518 NC pregnancies with ultrasound data were included. A general least squares model was used to examine the effect of fresh or frozen ET on fetal growth while adjusting for confounders.

    Main Outcome: MeasuresFetal growth velocity. SGA, LGA and macrosomia.

    Results: At 120 days, fetal weights were lower in fresh ET pregnancies compared with NC pregnancies. Thereafter fresh ET as well as FET fetuses had higher fetal weights than NC fetuses, with no differences between themselves until the second trimester. From 210 days, FET fetuses were heavier than fresh ET fetuses, whereas fresh ET fetuses had lower fetal weights than NC fetuses from 245 days. After fresh ET, SGA was more frequent, whereas LGA and macrosomia were less frequent, than after FET.

    Conclusions: This study gives new insights into the differences in fetal growth dynamics between fresh and frozen ET and NC pregnancies. Clinically relevant differences in proportions of SGA, LGA and macrosomia were observed.

    Place, publisher, year, edition, pages
    John Wiley & Sons, 2024
    National Category
    Gynaecology, Obstetrics and Reproductive Medicine
    Research subject
    Obstetrics and Gynaecology
    Identifiers
    urn:nbn:se:uu:diva-530270 (URN)10.1111/1471-0528.17786 (DOI)001161019100001 ()
    Available from: 2024-06-03 Created: 2024-06-03 Last updated: 2025-02-11Bibliographically approved
    3. Fetal growth after fresh and frozen embryo transfer and natural conception: a prospective cohort study
    Open this publication in new window or tab >>Fetal growth after fresh and frozen embryo transfer and natural conception: a prospective cohort study
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    (English)Manuscript (preprint) (Other academic)
    Keywords
    Fetal Growth, Assisted Reproduction, Embryo Transfer, Infertility
    National Category
    Gynaecology, Obstetrics and Reproductive Medicine
    Identifiers
    urn:nbn:se:uu:diva-548535 (URN)
    Available from: 2025-01-26 Created: 2025-01-26 Last updated: 2025-02-11
    4. Postnatal growth after fresh and frozen embryo transfer: a population-based register study
    Open this publication in new window or tab >>Postnatal growth after fresh and frozen embryo transfer: a population-based register study
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Gynaecology, Obstetrics and Reproductive Medicine
    Identifiers
    urn:nbn:se:uu:diva-548538 (URN)
    Available from: 2025-01-26 Created: 2025-01-26 Last updated: 2025-02-11
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  • Public defence: 2025-03-21 13:15 Brusewitzsalen, Uppsala
    Croicu, Mihai
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Peace and Conflict Research.
    Forecasting battles: New machine learning methods for predicting armed conflict2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Over the past decade, the field of conflict forecasting has undergone a remarkable metamorphosis, transforming from a series of isolated efforts with low predictive power into large, globe-spanning projects with impressive performance. However, despite this evolution, many challenges still remain. First, while we are good at predicting absolute risks, we are poor at predicting conflict dynamics (onsets, escalations, de-escalations and terminations). Second, we are over-reliant on spatio-temporal features and mechanistic models due to the nature of the event-data we use, thus excluding actor agency. Third, we do not handle either data or model uncertainty. Fourth, we are lagging behind the state-of-the-art in machine-learning. This dissertation attempts to resolve some of these salient difficulties, by contributing to six core elements of current-generation forecasting systems. First, time, by looking at the substantive effects and uncertainties of the temporal distance between data and forecast horizons. Second, space, by looking at the inherent uncertainties of high-resolution geospatial data and proposing a statistical method to address this. Third, feature space, by tackling the extreme feature sparsity in event-data and proposing a novel, deep active learning approach to mine features from existing large conflict-related text corpora. Fourth, substantive knowledge, by combining findings from the previous papers to take a fresh look at the microdynamics of conflict escalation. Fifth, the forecasting process itself, by building models that directly forecast from text, eliminating the intermediate step of manual data curation. Finally, the frontier of event-data, by looking at whether the news-media heavy way we collect violent fatal events can be extended to the collection of non-violent events. Methodologically, the dissertation introduces state-of-the art methods to the field, including the use of large language models, Gaussian processes, active learning and deep time series modelling. The six papers in the dissertation exhibit significant performance improvement, especially in forecasting dynamics.

    List of papers
    1. Introducing the UCDP Candidate Events Dataset
    Open this publication in new window or tab >>Introducing the UCDP Candidate Events Dataset
    2020 (English)In: Research & Politics, E-ISSN 2053-1680, Vol. 7, no 3, p. 1-8Article in journal (Refereed) Published
    Abstract [en]

    This article presents a new, monthly updated dataset on organized violence—the Uppsala Conflict Data Program Candidate Events Dataset. It contains recent observations of candidate events, a majority of which are eventually included in the Uppsala Conflict Data Program Georeferenced Event Dataset as part of its annual update after a careful vetting process. We describe the definitions, sources and procedures employed to code the candidate events, and a set of issues that emerge when coding data on organized violence in near-real time. Together, the Uppsala Conflict Data Program Candidate and Georeferenced Event Datasets minimize an inherent trade-off between update speed and quality control. Having monthly updated conflict data is advantageous for users needing near-real time monitoring of violent situations and aiming to anticipate future developments. To demonstrate this, we show that including them in a conflict forecasting system yields distinct improvements in terms of predictive performance: Average precision increases by 20–40% relative to using the Uppsala Conflict Data Program Georeferenced Event Dataset only. We also show that to ensure quality and consistency, revisiting the initial coding making use of sources that become available later is absolutely necessary.

    Keywords
    Armed conflict, event data, Africa, forecasting
    National Category
    Political Science (excluding Public Administration Studies and Globalisation Studies)
    Research subject
    Peace and Conflict Research; Peace and Conflict Research
    Identifiers
    urn:nbn:se:uu:diva-420461 (URN)10.1177/2053168020935257 (DOI)000575049900001 ()
    Funder
    EU, European Research Council, H2020-ERC-2015-AdG 694640Swedish National Infrastructure for Computing (SNIC)
    Available from: 2020-09-26 Created: 2020-09-26 Last updated: 2024-12-12Bibliographically approved
    2. Enhancing geospatial precision in conflict data: A stochastic approach to addressing known geographically imprecise observations in conflict event data
    Open this publication in new window or tab >>Enhancing geospatial precision in conflict data: A stochastic approach to addressing known geographically imprecise observations in conflict event data
    2023 (English)Conference paper, Oral presentation with published abstract (Other academic)
    Abstract [en]

    The proliferation of large-scale, geographically disaggregated data on armed conflicts, protests, and similar events has opened new avenues of research, but has also introduced significant data quality challenges. A notable yet often overlooked issue involves observations with “known geographic imprecision” (KGI), where event locations are unknown and instead arbitrarily assigned by dataset authors. Although this issue is widely recognized and accounts for up to a quarter of observations in datasets like UCDP GED, it is rarely addressed by users. This paper presents a stochastic method derived from the multiple-imputation literature, employing spatio-temporal Gaussian processes and leveraging latent actor-conflict features in the data to enhance location accuracy. Extensive Monte-Carlo simulations demonstrate that this approach substantially enhances the accuracy of these observations and improves predictive performance beyond the state-of-the-art when applied out-of-sample. Additionally, an adapted version of the UCDP GED dataset that employs this new procedure is provided, showcasing the practical application and benefits of the methodology.

    Place, publisher, year, edition, pages
    International Studies Association, 2023
    National Category
    Social and Economic Geography Other Social Sciences not elsewhere specified Peace and Conflict Studies Other Social Sciences not elsewhere specified
    Identifiers
    urn:nbn:se:uu:diva-544709 (URN)
    Conference
    64th International Studies Association Annual Convention, Montreal, Canada, 15-18 March, 2023
    Available from: 2024-12-07 Created: 2024-12-07 Last updated: 2025-02-20
    3. Deep active learning for data mining from conflict text corpora
    Open this publication in new window or tab >>Deep active learning for data mining from conflict text corpora
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    High-resolution event data on armed conflict and related processes have revolutionized the study of political contention. However, most datasets of this type only collect spatio-temporal and conflict intensity data at that level of detail. Information on dynamics, such as targets, tactics, and purposes, is rarely collected due to the substantial effort of collecting data. This study proposes an inexpensive, high-performance approach to increase the feature richness of such datasets by leveraging active learning -- an iterative process of improving a machine learning model based on guided human input at each step of the learning process. Active learning is employed to then fine-tune (train in steps) a large, encoder-only language model fitted to the rich corpus of textual data underlying such datasets. This allows for the extraction of features related to conflict dynamics, such as electoral violence and attacks on religious targets. The approach achieves a performance comparable to the human (gold-standard) coding, while reducing the necessary human annotation by as much as 99 percent.

    National Category
    Other Social Sciences not elsewhere specified Peace and Conflict Studies Other Social Sciences not elsewhere specified Political Science (excluding Public Administration Studies and Globalisation Studies) Computer Sciences
    Research subject
    Peace and Conflict Research; Machine learning
    Identifiers
    urn:nbn:se:uu:diva-544706 (URN)
    Available from: 2024-12-07 Created: 2024-12-07 Last updated: 2025-02-20
    4. Provocation by Design?: Holy Places, Public Transport, and Civil Conflict Escalation
    Open this publication in new window or tab >>Provocation by Design?: Holy Places, Public Transport, and Civil Conflict Escalation
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    What explains conflict escalation during civil war? This article explores whether provocative attacks on religious sites and public transport constitute a precursor to a surge of violence. One argument pertains that the symbolic and doctrinal importance of places of worship means that attacks on these will affect individuals and the community emotionally and thereby increase the risk of escalation. However, it can also be suggested that the everyday societal importance of a public space is similar for religious sites and public transport hubs. We test these arguments using novel new global event data on these forms of selective targeting for 1989-2015, and find that the risk of conflict escalation increase in the aftermath of either attacks on places of worship or public transport, suggesting that community behavior is more affected to disruptions of societal everyday life than to the importance of symbols.

    National Category
    Political Science (excluding Public Administration Studies and Globalisation Studies) Peace and Conflict Studies Other Social Sciences not elsewhere specified
    Research subject
    Political Science; Peace and Conflict Research; Peace and Conflict Research; Administrative Law; Peace and Conflict Research
    Identifiers
    urn:nbn:se:uu:diva-544707 (URN)
    Available from: 2024-12-07 Created: 2024-12-07 Last updated: 2025-02-20
    5. From newswire to nexus: Using text-based actor embeddings and transformer networks to forecast conflict dynamics
    Open this publication in new window or tab >>From newswire to nexus: Using text-based actor embeddings and transformer networks to forecast conflict dynamics
    2024 (English)Conference paper, Oral presentation with published abstract (Other academic)
    Abstract [en]

    This study advances the field of conflict forecasting by using text-based actor embeddings with transformer models to predict dynamic changes in violent conflict patterns at the actor level. More specifically, we combine newswire texts with structured conflict event data and leverage recent advances in Natural Language Processing (NLP) techniques to forecast escalations and de-escalations among conflicting actors, such as governments, militias, separatist movements, and terrorists. This new approach accurately and promptly captures the inherently volatile patterns of violent conflicts, which existing methods have not been able to achieve. To create this framework, we began by curating and annotating a vast international newswire corpus, leveraging hand-labeled event data from the Uppsala Conflict Data Program. By using this hybrid dataset,  our models can incorporate the textual context of news sources along with the precision and detail of structured event data. This combination enables us to make both dynamic and granular predictions about conflict developments. We validate our approach through rigorous back-testing against historical events, demonstrating superior out-of-sample predictive power. We find that our approach is quite effective in identifying and predicting phases of conflict escalation and de-escalation, surpassing the capabilities of traditional models. By focusing on actor interactions, our explicit goal is to provide actionable insights to policymakers, humanitarian organizations, and peacekeeping operations in order to enable targeted and effective intervention strategies.

    Place, publisher, year, edition, pages
    The American Political Science Association, 2024
    National Category
    Natural Language Processing Political Science (excluding Public Administration Studies and Globalisation Studies) Peace and Conflict Studies Other Social Sciences not elsewhere specified Computer Sciences
    Identifiers
    urn:nbn:se:uu:diva-544710 (URN)
    Conference
    120th Annual Meeting of the American Political Science Association, Philadelphia, United States of America, September 5--8
    Available from: 2024-12-07 Created: 2024-12-07 Last updated: 2025-02-20
    6. Reporting of Non-Fatal Conflict Events
    Open this publication in new window or tab >>Reporting of Non-Fatal Conflict Events
    2022 (English)In: International Interactions, ISSN 0305-0629, E-ISSN 1547-7444, Vol. 48, no 3, p. 450-470Article in journal (Refereed) Published
    Abstract [en]

    Temporally and spatial disaggregated datasets are commonly used to study political violence. Researchers are increasingly studying the data generation process itself to understand the selection processes by which conflict events are included in conflict datasets. This work has focused on conflict fatalities. In this research note, we explore how non-fatal conflict events are reported upon and enter into datasets of armed conflict. To do so, we compare reported non-fatal conflict events with the population of events in two direct observation datasets, collected using a boots-on-the-ground strategy: mass abductions in Nepal (1996-2006) and troop movements in Darfur. We show that at the appropriate level of aggregation media reporting on abductions in Nepal largely mirrors the "true" population of abductions, but at more disaggregated levels of temporal or spatial analysis, the match is poor. We also show that there is no overlap between a media-driven conflict dataset and directly-observed data on troop movements in Sudan. These empirics indicate that non-fatal data can suffer from serious underreporting and that this is particularly the case for events lacking elements of coercion. These findings are indicative of selection problems in regards to the reporting on non-fatal conflict events.

    Place, publisher, year, edition, pages
    Taylor & Francis, 2022
    Keywords
    Conflict, data, event data, non-violence, reporting bias
    National Category
    Public Health, Global Health and Social Medicine
    Identifiers
    urn:nbn:se:uu:diva-483047 (URN)10.1080/03050629.2022.2044325 (DOI)000768102400001 ()
    Funder
    EU, European Research Council, 694640 - ViEWS
    Available from: 2022-09-08 Created: 2022-09-08 Last updated: 2025-02-20Bibliographically approved
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  • Public defence: 2025-03-21 13:15 Sal X, Universitetshuset, Uppsala
    Lindqvist, Moa
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Educational Sciences, Department of Education.
    Striden om den högre utbildningen: En socioretorisk studie av remissyttranden inför svenska högskolereformer 1969–20072025Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis examines the evolving ideas and expectations surrounding higher education, focusing on the consultation processes preceding four major reforms of the Swedish higher education system. The study aims to understand how universities and societal stakeholders – including government agencies, trade unions, business organisations, and student unions – defined and justified the idea and function of higher education during these critical junctures. It explores how competing views on higher education’s purpose, organisation, and funding were negotiated in response to societal and labour market changes.

    The analysis adopts a socio-rhetorical perspective, treating consultation responses as strategic discursive acts reflecting power relations and institutional positions. By integrating pragmatics and sociology, four central elements are emphasised: the situation of the statement, genre, the dialogical dimension, and institutional conditions. These elements illuminate how values and arguments about the idea and function of higher education have been shaped and framed over time. The empirical material consists of consultation responses preceding major higher education reforms from the latter half of the 20th century to the early 21st century. The study analyses the responses submitted by universities, university colleges, and other societal stakeholders and how their statements were shaped by their institutional and historical contexts, focusing on the language, strategies, and perspectives employed.

    The findings reveal a significant shift in the idea and function of higher education over time. In the 1960s and 1970s, consultation responses often emphasised academic freedom, Bildung, and societal welfare. By the 1990s, these values were increasingly replaced by market-driven priorities, including efficiency, competitiveness, and alignment with labour market demands. The results also highlight how universities themselves transformed during this period, moving from collegial governance to hierarchical management structures. This organisational shift diminished collegial influence and redefined universities as actors within the framework of public administration.

    The thesis concludes that higher education remains a contested arena where external pressures and internal conflicts continuously reshape its idea and function. By analysing consultation responses as reflections of these dynamics, the study contributes to a deeper understanding of how language, power, and institutional transformation have shaped the idea and function of Swedish higher education.

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  • Public defence: 2025-03-25 09:00 Polhemsalen, Uppsala
    Tosun, Fatih Emre
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Electrical Engineering, Signals and Systems.
    Sensor Attack Detection in Artificial Pancreas Systems: A Control-theoretic Approach2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Type 1 Diabetes (T1D) has challenged humanity for over 3,500 years, from its earliest descriptions in ancient medical texts to today’s cutting-edge biotechnological solutions. Even today, T1D remains a growing global health concern and is the second most common chronic disease among children in Sweden. Although there is no cure, significant progress has been made in treatment strategies, particularly through the development of artificial pancreas (AP) systems. An AP is a closed-loop insulin delivery system that integrates a glucose sensor, an insulin pump, and a control algorithm to mimic the glucose-regulating function of a healthy pancreas. By continuously adjusting insulin infusion based on real-time glucose measurements, AP systems reduce the burden of diabetes management and improve long-term health outcomes.

    However, as AP systems rely on sensor data and wireless communication, they are susceptible to cyber threats. One such threat is sensor deception attacks, where an attacker manipulates the sensor readings to mislead the insulin delivery algorithm, potentially causing excessively low or high glucose levels. Detecting such attacks is particularly challenging due to natural glucose fluctuations caused by meal intake, which can mask adversarial manipulation.

    The need for computationally efficient and reliable anomaly detection algorithms is paramount, particularly in wearable medical devices such as the AP. To this end, model-based anomaly detection schemes offer a mathematically rigorous and lightweight alternative, enabling timely and accurate detection of anomalies, including cyberattacks, while meeting the real-time constraints of safety-critical systems. This thesis aims to advance model-based detection methods by integrating residual generation and evaluation techniques, optimizing the trade-off between detection speed and false alarm minimization. By contributing to the development of secure AP systems, this research aims to enhance patient safety and improve the quality of life for individuals with T1D.

    List of papers
    1. Quickest detection of bias injection attacks on the glucose sensor in the artificial pancreas under meal disturbances
    Open this publication in new window or tab >>Quickest detection of bias injection attacks on the glucose sensor in the artificial pancreas under meal disturbances
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    2024 (English)In: Journal of Process Control, ISSN 0959-1524, E-ISSN 1873-2771, Vol. 135, article id 103162Article in journal (Refereed) Published
    Abstract [en]

    Modern glucose sensors deployed in closed -loop insulin delivery systems, so-called artificial pancreas use wireless communication channels. While this allows a flexible system design, it also introduces vulnerability to cyberattacks. Timely detection and mitigation of attacks are imperative for device safety. However, large unknown meal disturbances are a crucial challenge in determining whether the sensor has been compromised or the sensor glucose trajectories are normal. We address this issue from a control -theoretic security perspective. In particular, a time -varying Kalman filter is employed to handle the sporadic meal intakes. The filter prediction error is then statistically evaluated to detect anomalies if present. We compare two state-of-the-art online anomaly detection algorithms, namely the ᅵᅵᅵᅵᅵᅵ2 and CUSUM tests. We establish a robust optimal detection rule for unknown bias injections. Even if the optimality holds only for the restrictive case of constant bias injections, we show that the proposed model -based anomaly detection scheme is also effective for generic non -stealthy sensor deception attacks through numerical simulations.

    Place, publisher, year, edition, pages
    Elsevier, 2024
    Keywords
    Type 1 diabetes mellitus, Artificial pancreas, Quickest change detection, Control-theoretic security, Sensor deception attack
    National Category
    Control Engineering
    Identifiers
    urn:nbn:se:uu:diva-525038 (URN)10.1016/j.jprocont.2024.103162 (DOI)001164643000001 ()
    Funder
    Swedish Research Council, 2018-04396Swedish Foundation for Strategic Research
    Available from: 2024-03-27 Created: 2024-03-27 Last updated: 2025-02-02Bibliographically approved
    2. Robust Sequential Detection of Non-stealthy Sensor Deception Attacks in an Artificial Pancreas System
    Open this publication in new window or tab >>Robust Sequential Detection of Non-stealthy Sensor Deception Attacks in an Artificial Pancreas System
    2023 (English)In: 2023 62nd IEEE Conference on Decision and Control (CDC), Institute of Electrical and Electronics Engineers (IEEE), 2023, p. 2827-2832Conference paper, Published paper (Refereed)
    Abstract [en]

    This paper considers deterministic sensor deception attacks in closed-loop insulin delivery. Since the quality of decision-making in control systems heavily relies on accurate sensor measurements, timely detection of attacks is imperative. To this end, we consider a model-based anomaly detection scheme based on Kalman filtering and sequential change detection. In particular, we derive the minimax robust CUSUM and Shewhart tests that minimizes the worst-case mean detection delay and maximizes the instant detection rate, respectively. As a byproduct of our analysis, we show that the notorious.2 test shares an interesting optimality property with the twosided Shewhart test. Finally, we show that one-sided sequential detectors can significantly improve sensor anomaly detection for preventing overnight hypoglycemia which can be fatal.

    Place, publisher, year, edition, pages
    Institute of Electrical and Electronics Engineers (IEEE), 2023
    Series
    IEEE Conference on Decision and Control, ISSN 0743-1546, E-ISSN 2576-2370
    National Category
    Control Engineering
    Identifiers
    urn:nbn:se:uu:diva-525489 (URN)10.1109/CDC49753.2023.10384255 (DOI)001166433802058 ()979-8-3503-0124-3 (ISBN)979-8-3503-0125-0 (ISBN)
    Conference
    62nd IEEE Conference on Decision and Control (CDC), DEC 13-15, 2023, IEEE Control Syst Soc, Singapore, SINGAPORE
    Funder
    Swedish Research Council, 2018-04396Swedish Foundation for Strategic Research
    Available from: 2024-03-25 Created: 2024-03-25 Last updated: 2025-02-02Bibliographically approved
    3. Kullback-Leibler Divergence-Based Observer Design Against Sensor Bias Injection Attacks in Single-Output Systems
    Open this publication in new window or tab >>Kullback-Leibler Divergence-Based Observer Design Against Sensor Bias Injection Attacks in Single-Output Systems
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    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    This paper considers observer-based detection of sensor bias injection attacks (BIAs) on linear cyber-physical systems with single output driven by Gaussian noise. Despite their simplicity, BIAs pose a severe risk to systems with integrators, which we refer to as integrator vulnerability. Specifically, the residual generated by any linear observer is indistinguishable under attack and normal operation at steady-state, making BIAs detectable only during transients. To address this, we propose a principled method based on Kullback-Liebler divergence to design a residual generator that significantly increases the signal-to-noise ratio against BIAs. For systems without integrator vulnerability, our method also enables a trade-off between transient and steady-state detectability. The effectiveness of the proposed method is demonstrated through numerical comparisons with three state-of-the-art residual generators.

    Keywords
    Cyber-physical systems, sensor deception attacks, bias injection attacks, observer-based anomaly detection
    National Category
    Control Engineering
    Identifiers
    urn:nbn:se:uu:diva-548790 (URN)
    Available from: 2025-01-28 Created: 2025-01-28 Last updated: 2025-02-11
    4. Kullback-Leibler Divergence-Based Filter Design Against Bias Injection Attacks
    Open this publication in new window or tab >>Kullback-Leibler Divergence-Based Filter Design Against Bias Injection Attacks
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Control Engineering
    Identifiers
    urn:nbn:se:uu:diva-548792 (URN)
    Available from: 2025-02-02 Created: 2025-02-02 Last updated: 2025-02-02
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  • Public defence: 2025-03-27 09:15 Hall IV, University main building, Uppsala
    Yohannes, Kalkidan
    Uppsala University, WoMHeR (Centre for Women’s Mental Health during the Reproductive Lifespan). Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Centre for Health and Sustainability.
    The dynamics of women’s homelessness in Ethiopia: Understanding the lives of women experiencing homelessness and the services and policies designed to meet their mental health and well-being needs2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis aimed to gain a deeper understanding of the lives of women experiencing homelessness and the services and policies designed to meet their mental health and well-being needs by exploring lived experiences and multiple perspectives of both women of reproductive age and individuals providing homeless-focused mental health and psychosocial services in Addis Ababa, Ethiopia.

    For Paper I, a photovoice study, women experiencing homelessness (n=9) were provided with cameras and asked to photograph their lives on the streets and discuss the images. Data from the photographs, interviews, and discussions were co-analysed with the women, and reflexive thematic analysis was also performed. Findings revealed that homeless women were deprived of basic needs, struggled with addiction, humiliated, and treated as social pariahs. Further, many children on the streets struggled with adversity from an early age, being subjected to violence and exploitation.

    Based on in-depth interviews with 19 women who experienced homelessness, Paper II showed how the common threads of abuse, micro-level relational factors, and housing issues shaped women’s trajectories through homelessness. The reflexive thematic analysis identified four main themes: trauma from childhood abuse, sexual violence, barriers to leaving street living, and sources of hope. The findings highlighted how re-traumatisation on the streets fuels these adverse traumatic experiences. However, although they faced personal, economic, and normative barriers, some women highlighted their resilience, willingness to seek support, and reliance on their strength and faith.

    Papers III and IV recruited participants from government and non-government organisations. The findings of the inductive thematic analysis in Paper III demonstrated that contradictory beliefs and practices, problem−solution incompatibility, and mismatched resources all hindered the provision of psychosocial services to women experiencing homelessness.

    The data collected for Paper IV were analysed using Shiffman and Smith’s political prioritisation framework. The results indicated gaps in actors’ power, how homelessness is portrayed in varying political contexts, and other issues of this topic (including lack of reliable indicators, effective interventions, and sufficient information on the problem’s severity). Overall, the thesis identified that interventions targeting individual-level vulnerabilities to systemic-level challenges are needed to address the multifaceted aspects of women’s homelessness.

    List of papers
    1. “Sleepless nights are a daily reality for us” how women experiencing homelessness in Addis Ababa, Ethiopia describe street life: a photovoice study
    Open this publication in new window or tab >>“Sleepless nights are a daily reality for us” how women experiencing homelessness in Addis Ababa, Ethiopia describe street life: a photovoice study
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    2025 (English)In: Frontiers in Public Health, E-ISSN 2296-2565, Vol. 13, article id 1488770Article in journal (Refereed) Published
    Abstract [en]

    Introduction: Homelessness among women of reproductive age is a globalproblem. Several unique gender-based issues affect homeless women’s wellbeing, including reproductive health issues, their homelessness experiences,and a high rate of sexual violence. In this study, we aimed to describe women’sexperiences of street homelessness in their own terms and their suggestions toaddress their unmet needs.Methods: This photovoice study draws on photos, focus group discussions, andsemi-structured interviews. We conducted the study in collaboration with womenin their reproductive years experiencing homelessness (n = 9). A total of 80 photoswere taken, and 40 were chosen to be discussed in interviews and further focusgroup discussions. The participating women selected photographs, explained theirsignificance, and codified them based on how they related to their lives. Data fromthese discussions were then analysed using a reflexive thematic approach.Results: Four themes were developed from the data: (a) deprivation of basicneeds; (b) experiencing dependency, shame, and seclusion while dealingwith the burden of street life; (c) the vulnerability and neglect of children; and(d) being resilient to harsh conditions. In this study, women’s street life wascharacterised by numerous unfavourable aspects, including unmet needs,human rights violations, social exclusions, substance use, and child protectionissues. Participants provided suggestions for change and confirmed their beliefthat adequate housing represents one of the most urgent unmet basic needsof people experiencing homelessness. They also emphasised the critical needfor employment opportunities, non-discriminatory provision of social support,treatment programs for substance misuse, and legal and social protection.Conclusion: This study contributes to understanding how women experiencinghomelessness describe and articulate their living circumstances and whatthey perceive needs to be addressed. Based on participants’ proposal forchange, comprehensive services are needed to address women’s multifacetedissues. However, the mitigation strategies and long-term effects of women’shomelessness require further research.

    Place, publisher, year, edition, pages
    Frontiers Media S.A., 2025
    Keywords
    photovoice, participatory research, women’s homelessness, rooflessness, qualitative research, Ethiopia, East Africa
    National Category
    Social Work
    Identifiers
    urn:nbn:se:uu:diva-549794 (URN)10.3389/fpubh.2025.1488770 (DOI)
    Available from: 2025-02-10 Created: 2025-02-10 Last updated: 2025-02-24Bibliographically approved
    2. "I had no choice but to escape": Exploring women's early life experiences, drivers, and trajectories through street homelessness in Addis Ababa, Ethiopia
    Open this publication in new window or tab >>"I had no choice but to escape": Exploring women's early life experiences, drivers, and trajectories through street homelessness in Addis Ababa, Ethiopia
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    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Background: Studies show that women’s trajectories through homelessness are shaped by gendered individual susceptibility, dysfunctional family dynamics, and social norms, as well as high rates of violence. Although women’s homelessness, specifically that of single mothers, often has a significant impact on the lives of women and their children, there is a dearth of research on this area in Ethiopia. Therefore, the purpose of this study was to explore homeless women’s early life experiences, their trajectories through homelessness, and the challenges inherent in community reintegration, as they perceive them. 

    Method: We conducted a qualitative study in December 2023 using semi-structured interviews. We purposively selected homeless women of reproductive age from the beneficiaries of a local civil society in Addis Ababa, Ethiopia (n = 19). 

    Results: ‘Childhood trauma from abuse’, ‘Sexual violence’, ‘Barriers to leaving street living, and ‘Sources of hope’ were four themes identified from the data. Despite differences in the reasons for homelessness and the routes that led the women to the streets, most of them experienced abuse, neglect, and exploitation in their early years of life. Rather than giving them a window into healing from their childhood trauma, the street further exposed women to sexual abuse, addiction, and underserved justice. Although there were personal, economic, and normative impediments, some women highlighted how they accepted the situation, looked for support, and relied on their strength and faith. 

    Conclusions: The findings highlight how the trajectories through homelessness were shaped by abuse as the common thread in the lived experiences of homeless women in Addis Ababa, Ethiopia. Given the highly gendered and traumatic nature of their situation, our results call for action to address the need for contextualizing tailored and gender-responsive, multi-level trauma-focused domestic violence and sexual violence interventions and rehabilitation services, as well as reintegration mechanism for homeless women of reproductive age.

    Keywords
    women’s homelessness, abuse, pathways, drivers, community reintegration, a qualitative study, Ethiopia
    National Category
    Social Work Public Health, Global Health and Social Medicine
    Research subject
    Psychology
    Identifiers
    urn:nbn:se:uu:diva-550208 (URN)
    Available from: 2025-02-12 Created: 2025-02-12 Last updated: 2025-02-14Bibliographically approved
    3. Contradictions hindering the provision of mental healthcare and psychosocial services to women experiencing homelessness in Addis Ababa, Ethiopia: service providers' and programme coordinators' experiences and perspectives
    Open this publication in new window or tab >>Contradictions hindering the provision of mental healthcare and psychosocial services to women experiencing homelessness in Addis Ababa, Ethiopia: service providers' and programme coordinators' experiences and perspectives
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    2023 (English)In: BMC Health Services Research, E-ISSN 1472-6963, Vol. 23, article id 821Article in journal (Refereed) Published
    Abstract [en]

    Background: Mental health conditions are among the health issues associated with homelessness, and providing mental healthcare to people experiencing homelessness is challenging. Despite the pressing issue of homelessness in Addis Ababa, Ethiopia, there is scant research on how service providers address women's mental health and psychosocial needs. Therefore, we explored service providers' and programme coordinators' perceptions and experiences regarding mental healthcare and psychosocial services delivery to women experiencing street homelessness in the city.

    Methods: We conducted a descriptive qualitative study with selected healthcare and social support providers and programme coordinators. The study involved 34 participants from governmental and non-governmental organisations in Addis Ababa, Ethiopia. Data were analysed using an inductive thematic approach.

    Results: Four themes were derived from the analysis. The first of these was "divergent intentions and actions". While service providers and programme coordinators showed empathy and compassion, they also objectified and blamed people for their own homelessness. They also expressed opposing views on mental health stigma and compassion for these people. The second theme addressed "problem-solution incompatibility", which focused on the daily challenges of women experiencing homelessness and the types of services participants prioritised. Service providers and programme coordinators proposed non-comprehensive support despite the situation's complexity. The participants did not emphasise the significance of gender-sensitive and trauma-informed care for women experiencing street homelessness in the third theme, "the lack of gendered and trauma-informed care despite an acknowledgement that women face unique challenges". The fourth theme, "mismatched resources," indicated structural and systemic barriers to providing services to homeless women.

    Conclusions:Conflicting attitudes and practices exist at the individual, organisational, and systemic levels, making it challenging to provide mental healthcare and psychosocial services to women experiencing homelessness. An integrated, gender-sensitive, and trauma-informed approach is necessary to assist women experiencing homelessness.

    Place, publisher, year, edition, pages
    BioMed Central (BMC), 2023
    Keywords
    Qualitative research, Mental healthcare, Psychosocial support, Street homelessness, Women of reproductive age, Low- and middle-income countries, Service provider perception, Ethiopia
    National Category
    Social Work Nursing Public Health, Global Health and Social Medicine
    Identifiers
    urn:nbn:se:uu:diva-510011 (URN)10.1186/s12913-023-09810-z (DOI)001040777000002 ()37528372 (PubMedID)
    Available from: 2023-08-28 Created: 2023-08-28 Last updated: 2025-02-20Bibliographically approved
    4. Addressing the needs of Ethiopia's street homeless women of reproductive age in the health and social protection policy: a qualitative study
    Open this publication in new window or tab >>Addressing the needs of Ethiopia's street homeless women of reproductive age in the health and social protection policy: a qualitative study
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    2023 (English)In: International Journal for Equity in Health, E-ISSN 1475-9276, Vol. 22, article id 80Article in journal (Refereed) Published
    Abstract [en]

    Introduction: Globally, homelessness is a growing concern, and homeless women of reproductive age are particularly vulnerable to adverse physical, mental, and reproductive health conditions, including violence. Although Ethiopia has many homeless individuals, the topic has received little attention in the policy arena. Therefore, we aimed to understand the reason for the lack of attention, with particular emphasis on women of reproductive age.

    Methods: This is a qualitative study; 34 participants from governmental and non-governmental organisations responsible for addressing homeless individuals' needs participated in in-depth interviews. A deductive analysis of the interview materials was applied using Shiffman and Smith's political prioritisation framework.

    Results: Several factors contributed to the underrepresentation of homeless women's health and well-being needs in the policy context. Although many governmental and non-governmental organisations contributed to the homeless-focused programme, there was little collaboration and no unifying leadership. Moreover, there was insufficient advocacy and mobilisation to pressure national leaders. Concerning ideas, there was no consensus regarding the definition of and solution to homeless women's health and social protection issues. Regarding political contexts and issue characteristics, a lack of a well-established structure, a paucity of information on the number of homeless women and the severity of their health situations relative to other problems, and the lack of clear indicators prevented this issue from gaining political priority.

    Conclusions: To prioritise the health and well-being of homeless women, the government should form a unifying collaboration and a governance structure that addresses the unmet needs of these women. It is imperative to divide responsibilities and explicitly include homeless people and services targeted for them in the national health and social protection implementation documents. Further, generating consensus on framing the problems and solutions and establishing indicators for assessing the situation is vital.

    Place, publisher, year, edition, pages
    BioMed Central (BMC), 2023
    Keywords
    Health, Well-being, Street homeless women, Street homelessness, Ethiopia, Qualitative research, Policy agenda, Shiffman and Smith's framework, Political priority, Low and Middle-Income Countries
    National Category
    Social Work
    Identifiers
    urn:nbn:se:uu:diva-502514 (URN)10.1186/s12939-023-01874-x (DOI)000981576900001 ()37143037 (PubMedID)
    Available from: 2023-05-26 Created: 2023-05-26 Last updated: 2025-02-12Bibliographically approved
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  • Public defence: 2025-03-27 09:15 room A1:111a, Uppsala
    Mickols, Evgeniya
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy. Uppsala University.
    Advanced In Vitro Systems for Studies of Drug Disposition in the Human Liver2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In drug development, in vitro models are used to assess specific aspects of in vivo Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) properties of the drugs. Relevant in vitro assays play a crucial role in bringing safe and efficacious compounds to the market, and contribute to the Replacement, Refinement and Reduction (3Rs) of animal experiments.

    Much effort is now being directed to the development of different physiologically relevant advanced in vitro models. One of such models is three-dimensional spheroids of primary human hepatocytes (3D PHH). These 3D PHH closely resemble the in vivo liver at the transcriptome, proteome and metabolome levels. However, 3D PHH are cultured under different conditions and the reproducibility of these culture varies greatly across laboratories. This thesis contributes to harmonization of 3D PHH culture approaches. 

    First, the effect of the cell culture medium on 3D PHH was evaluated. We compared various commercially available media with undisclosed or known content, and also assessed the influence of commonly used medium components such as glucose, insulin, zinc and foetal bovine serum. The choice of cell culture medium had a pronounced effect on the hepatic phenotypes. Importantly, we demonstrate that 3D PHH could be successfully cultured in the animal-serum free physiologically relevant medium with fasting levels of insulin and glucose. 

    Further, we appraised the effect of ultra-low attachment culture plates on the performance of 3D PHH, and demonstrated that Corning and Biofloat plates facilitate the formation of spheroids with most physiologically relevant phenotypes. 

    Throughout all projects included in this doctoral thesis, mass-spectrometry based global proteomics served as indispensable tool for phenotypic description of 3D PHH. However, the choice of workflow for this analysis has a significant impact on biological interpretation. Here, twelve different proteomics workflows for phenotypic description of 3D PHH were compared, and these results will aid researcher in our field in making an informed decision on the approach to the phenotypical screening of liver spheroid cultures.

    In conclusion, this thesis provides an improved understanding and optimization of 3D primary human hepatocyte spheroid cultures, and deep integration of this in vitro model into drug development pipelines.

    List of papers
    1. Conditions for maintenance of hepatocyte differentiation and function in 3D cultures
    Open this publication in new window or tab >>Conditions for maintenance of hepatocyte differentiation and function in 3D cultures
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    2021 (English)In: iScience, E-ISSN 2589-0042, Vol. 24, no 11, article id 103235Article in journal (Refereed) Published
    Abstract [en]

    Spheroid cultures of primary human hepatocytes (PHH) are used in studies of hepatic drug metabolism and toxicity. The cultures are maintained under different cone-lions, with possible confounding results. We performed an in-depth analysis of the influence of various culture conditions to find the optimal conditions for the maintenance of an in vivo like phenotype. The formation, protein expression, and function of PHH spheroids were followed for three weeks in a high-throughput 384-well format. Medium composition affected spheroid histology, global proteome profile, drug metabolism and drug-induced toxicity. No epithelial-mesenchymel transition was observed. Media with fasting glucose and insulin levels gave spheroids with phenotypes closest to normal PHH. The most expensive medium resulted in PHH features most divergent from that of native PHH. Our results provide a protocol for culture of healthy PHH with maintained function a prerequisite for studies of hepatocyte homeostasis and more reproducible hepatocyte research.

    Place, publisher, year, edition, pages
    Cell Press, 2021
    National Category
    Cell and Molecular Biology
    Identifiers
    urn:nbn:se:uu:diva-463531 (URN)10.1016/j.isci.2021.103235 (DOI)000730173500005 ()34746700 (PubMedID)
    Funder
    Swedish Research Council, 2822Swedish Research Council, 01951Swedish Cancer SocietyTore Nilsons Stiftelse för medicinsk forskning, 00754
    Available from: 2022-01-17 Created: 2022-01-17 Last updated: 2025-01-28Bibliographically approved
    2. OCT1 (SLC22A1) transporter kinetics and regulation in primary human hepatocyte 3D spheroids
    Open this publication in new window or tab >>OCT1 (SLC22A1) transporter kinetics and regulation in primary human hepatocyte 3D spheroids
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    2024 (English)In: Scientific Reports, E-ISSN 2045-2322, Vol. 14, no 1, article id 17334Article in journal (Refereed) Published
    Abstract [en]

    3D spheroids of primary human hepatocytes (3D PHH) retain a differentiated phenotype with largely conserved metabolic function and proteomic fingerprint over weeks in culture. As a result, 3D PHH are gaining importance as a model for mechanistic liver homeostasis studies and in vitro to in vivo extrapolation (IVIVE) in drug discovery. However, the kinetics and regulation of drug transporters have not yet been assessed in 3D PHH. Here, we used organic cation transporter 1 (OCT1/SLC22A1) as a model to study both transport kinetics and the long-term regulation of transporter activity via relevant signalling pathways. The kinetics of the OCT1 transporter was studied using the fluorescent model substrate 4-(4-(dimethylamino)styryl)-N-methylpyridinium (ASP+) and known OCT1 inhibitors in individual 3D PHH. For long-term studies, 3D PHH were treated with xenobiotics for seven days, after which protein expression and OCT1 function were assessed. Global proteomic analysis was used to track hepatic phenotypes as well as prototypical changes in other regulated proteins, such as P-glycoprotein and Cytochrome P450 3A4. ASP+ kinetics indicated a fully functional OCT1 transporter with a Km value of 14 ± 4.0µM as the mean from three donors. Co-incubation with known OCT1 inhibitors decreased the uptake of ASP+ in the 3D PHH spheroids by 35–52%. The long-term exposure studies showed that OCT1 is relatively stable upon activation of nuclear receptor signalling or exposure to compounds that could induce inflammation, steatosis or liver injury. Our results demonstrate that 3D PHH spheroids express physiologically relevant levels of fully active OCT1 and that its transporter kinetics can be accurately studied in the 3D PHH configuration. We also confirm that OCT1 remains stable and functional during the activation of key metabolic pathways that alter the expression and function of other drug transporters and drug-metabolizing enzymes. These results will expand the range of studies that can be performed using 3D PHH.

    Place, publisher, year, edition, pages
    Springer Nature, 2024
    Keywords
    Hepatocyte, Liver, Uptake, ASP+, OCT1, Drug transport, Drug-Drug interaction, Spheroid, 3D culture, Proteomics
    National Category
    Medical Biotechnology (with a focus on Cell Biology (including Stem Cell Biology), Molecular Biology, Microbiology, Biochemistry or Biopharmacy)
    Identifiers
    urn:nbn:se:uu:diva-535505 (URN)10.1038/s41598-024-67192-6 (DOI)001281273100063 ()39068198 (PubMedID)2-s2.0-85199759857 (Scopus ID)
    Funder
    Uppsala UniversitySwedish Research Council, 2020-01586Swedish Research Council, 2017-01951
    Note

    These authors contributed equally: Evgeniya Mickols, Alina Meyer and Niklas Handin.

    Available from: 2024-08-01 Created: 2024-08-01 Last updated: 2025-02-13Bibliographically approved
    3. The choice of ultra-low attachment plates impacts primary human and primary canine hepatocyte spheroid formation, phenotypes, and function
    Open this publication in new window or tab >>The choice of ultra-low attachment plates impacts primary human and primary canine hepatocyte spheroid formation, phenotypes, and function
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    2024 (English)In: Biotechnology Journal, ISSN 1860-6768, E-ISSN 1860-7314, Vol. 19, no 2, article id e2300587Article in journal (Refereed) Published
    Abstract [en]

    Organotypic three-dimensional liver spheroid cultures in which hepatic cells retain their molecular phenotype and functionality have emerged as powerful tools for preclinical drug development. In recent years a multitude of culture systems have been developed; however, a thorough side-by-side benchmarking of the different methods is lacking. Here, we compared the performance of ten different 96- and 384-well microplate types to support spheroid formation and long-term culture. Specifically, we evaluated differences in spheroid formation kinetics, viability, functionality, expression patterns, and their utility for hepatotoxicity assessments using primary human hepatocytes (PHH) and primary canine hepatocytes (PCH). All 96-well plates enabled formation of PHH liver spheroids, albeit with differences between plates in spheroid size, geometry, and reproducibility. Performance of different 384-wells was less consistent. Only 6/10 microplates supported the formation of PCH aggregates. Interestingly, even if PCH aggregates in these six microplates were more loosely packed than PHH spheroids, they maintained their function and were compatible with long-term pharmacological and toxicological assays. Overall, Corning and Biofloat plates showed the best performance in the formation of both human and canine liver spheroids with highest viability, most physiologically relevant phenotypes, superior CYP activity and lowest coefficient of variation in toxicity assays. The presented data constitutes a valuable resource that demonstrates the impacts of current ultra-low attachment plates on liver spheroid metrics and can guide evidence-based plate selection. Combined, these results have important implications for the cross-comparison of different studies and can facilitate the standardization and reproducibility of three-dimensional liver culture experiments. We assessed the performance of ten different 384- and 96-well ultra-low attachment (ULA) microplates in facilitating three-dimensional spheroid culture of primary human hepatocytes (PHH) and primary canine hepatocytes (PCH) by examining effects on formation kinetics, spheroid morphology, long-term stability, functionality, expression signatures, and utility for hepatotoxicity assessment. Significant variations in experimental endpoints were observed between plates. These results can guide the optimization of spheroid experiments and contribute to the standardization of testing in three-dimensional organotypic liver cultures. image

    Place, publisher, year, edition, pages
    John Wiley & Sons, 2024
    Keywords
    cell culture, liver spheroids, medical biotechnology, metabolism, 3D cell culture
    National Category
    Biomedical Laboratory Science/Technology
    Identifiers
    urn:nbn:se:uu:diva-525050 (URN)10.1002/biot.202300587 (DOI)001172777800001 ()38403411 (PubMedID)
    Funder
    Swedish Research Council, 2019-01837Swedish Research Council, 2021-02801Swedish Research Council, 2023-03015
    Available from: 2024-03-20 Created: 2024-03-20 Last updated: 2025-01-28Bibliographically approved
    4. Proteomic workflows for deep phenotypic profiling of 3D organotypic liver models
    Open this publication in new window or tab >>Proteomic workflows for deep phenotypic profiling of 3D organotypic liver models
    2024 (English)In: Biotechnology Journal, ISSN 1860-6768, E-ISSN 1860-7314, Vol. 19, no 3, article id e2300684Article in journal (Refereed) Published
    Abstract [en]

    Organotypic human tissue models constitute promising systems to facilitate drug discovery and development. They allow to maintain native cellular phenotypes and functions, which enables long-term pharmacokinetic and toxicity studies, as well as phenotypic screening. To trace relevant phenotypic changes back to specific targets or signaling pathways, comprehensive proteomic profiling is the gold-standard. A multitude of proteomic workflows have been applied on 3D tissue models to quantify their molecular phenotypes; however, their impact on analytical results and biological conclusions in this context has not been evaluated. The performance of twelve mass spectrometry-based global proteomic workflows that differed in the amount of cellular input, lysis protocols and quantification methods was compared for the analysis of primary human liver spheroids. Results differed majorly between protocols in the total number and subcellular compartment bias of identified proteins, which is particularly relevant for the reliable quantification of transporters and drug metabolizing enzymes. Using a model of metabolic dysfunction-associated steatotic liver disease, we furthermore show that critical disease pathways are robustly identified using a standardized high throughput-compatible workflow based on thermal lysis, even using only individual spheroids (1500 cells) as input. The results increase the applicability of proteomic profiling to phenotypic screens in organotypic microtissues and provide a scalable platform for deep phenotyping from limited biological material.

    Place, publisher, year, edition, pages
    Wiley-VCH Verlagsgesellschaft, 2024
    Keywords
    ADME proteins, expression profiling, hepatocellular steatosis, mass-spectrometry, primary human hepatocytes, proteomics, spheroids
    National Category
    Biochemistry Molecular Biology Cell and Molecular Biology
    Identifiers
    urn:nbn:se:uu:diva-526263 (URN)10.1002/biot.202300684 (DOI)001189991900001 ()38509783 (PubMedID)
    Funder
    Swedish Research Council, 2021-02801Swedish Research Council, 2023-03015Knut and Alice Wallenberg Foundation, VC-2021-0026
    Available from: 2024-04-11 Created: 2024-04-11 Last updated: 2025-02-20Bibliographically approved
    5. Animal product-free formation and cultivation of 3D primary hepatocyte spheroids
    Open this publication in new window or tab >>Animal product-free formation and cultivation of 3D primary hepatocyte spheroids
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    3D cultures of primary human hepatocytes (3D PHH) are successfully used to reduce and replace the use of animal experiments in biomedical research. Yet, the initial formation of 3D PHH is highly dependent on the supplementation with fetal bovine serum (FBS). However, the molecular composition of FBS and its effects on cultured cells are poorly understood. Moreover, FBS is prone to batch-to-batch variation, immunogenic risk and lack of adherence to the replacement, refinement, and reduction (3Rs) of animal experiments. Here, we demonstrate that FBS can be fully replaced by animal-free substitutes, thus facilitating fully chemically defined and animal serum-free 3D PHH cultures. Specifically, we combined a previously developed animal-free substitute cocktail (Rafnsdóttir et al., 2023) with a normoglycemic (5.5 mM glucose and 0.58 ng/mL insulin) chemically defined culture medium (Handin et al., 2023). Morphological and viability evaluations, along with global proteomics data, demonstrated that serum-free cultured 3D PHH have equal or superior viability and functional performance of cytochrome P450s, rendering this medium useful for long-term studies and in vitro ADMET applications. This study marks a significant advancement in the development of animal serum-free culture conditions for primary human cell cultures, paving the way for more reliable and ethical in vitro studies.

    Keywords
    3D PHH, serum-free
    National Category
    Pharmaceutical and Medical Biotechnology Pharmacology and Toxicology
    Identifiers
    urn:nbn:se:uu:diva-548556 (URN)
    Available from: 2025-01-27 Created: 2025-01-27 Last updated: 2025-01-28Bibliographically approved
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  • Public defence: 2025-03-27 11:30 room 101195, Uppsala
    Elhanoty, Mohamed F.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Exploring Microscopic Mechanisms of Ultrafast Magnetization Dynamics: Bridging Experimental Observables with Quantum Mechanical Insights through Ab Initio Methods2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The optical manipulation of magnetic materials using ultrashort laser pulses offers a promising avenue for advancing spintronics and magnetic data storage technologies. However, probing and disentangling the microscopic mechanisms driving magnetization changes remains challenging due to the complex interplay of multiple degrees of freedom at femtosecond timescales and Ångstrom length scales. In this thesis, we employ a combination of fully ab initio time-dependent density functional theory (TDDFT) and linear response theory to investigate the real-time dynamics of spin and electronic excitations in magnetic materials. The study focuses on magnetization dynamics and their various spectroscopic fingerprints in typical pump-probe experiments for a wide range of materials, including simple transition metal magnets, hybrid Stoner-Heisenberg alloys, and Heusler alloys such as Co2MnGa and Co2MnGe. We calculate time-resolved changes in magnetization and magneto-optical responses from first principles, enabling direct comparisons between experimental observations and theoretical predictions. 

    Our results identify spin flips mediated by spin-orbit coupling as the primary demagnetization mechanism in simple magnetic elements, while optical intersite spin transfer (OISTR) emerges as a key process in multicomponent magnetic alloys under laser excitation. We also demonstrate the efficient control of rigid magnetic moments in Heisenberg magnets through the OISTR mechanism on femtosecond timescales. Furthermore, by engineering valence bands via elemental substitution, we reveal how band modulation, spin lifetimes, and crystalline disorder influence transient signals measured at specific probing energies. 

    We investigate discrepancies in the energy-dependent signatures of microscopic processes at various probing energies, highlighting the importance of accurately interpreting transient signals in magneto-optical experiments. Our findings reveal that induced magnetization changes are significantly smaller than those inferred from experimental measurements, indicating a complex interplay of ultrafast microscopic processes. These observations exhibit diverse energy-dependent signatures, driven by the competition between ultrafast microscopic processes induced by the pump laser. Moreover, our results highlight the pivotal role of quantum mechanical selection rules in distinguishing genuine pump-induced dynamics from artifacts introduced by specific optical probe choices. 

    Finally, this thesis explores the limitations of TDDFT in capturing correlation effects in dynamically evolving systems and emphasizes their significance in interpreting transient absorption spectra of fcc Ni at the L-edge. Collectively, this work provides key insights into the interplay between optical excitations, spin flips, and selection rules, improving the interpretation of pump-probe experimental measurements and advancing the theoretical framework for ultrafast magnetization dynamics. 

    List of papers
    1. Element-selective ultrafast magnetization dynamics of hybrid Stoner-Heisenberg magnets
    Open this publication in new window or tab >>Element-selective ultrafast magnetization dynamics of hybrid Stoner-Heisenberg magnets
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    2022 (English)In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 105, no 10, article id L100401Article in journal (Refereed) Published
    Abstract [en]

    Stoner and Heisenberg excitations in magnetic materials are inherently different. The first involves an effective reduction of the exchange splitting, whereas the second comprises excitation of spin waves. In this work, we test the impact of these two excitations in the hybrid Stoner-Heisenberg system of FePd. We present a microscopic picture of ultrafast demagnetization dynamics in this alloy, which represents both components of strong local exchange splitting in Fe and induced polarization in Pd. We identify the spin-orbit coupling (SOC) and the optical intersite spin transfer (OISTR) as the two dominant factors for demagnetization at ultrashort timescales. Remarkably, the drastic difference in the origin of the magnetic moment of the Fe and Pd species is not deciding the initial magnetization dynamics in this alloy. By tuning the external laser pulse, the extrinsic OISTR can be manipulated for site-selective demagnetization on femtosecond timescales providing the fastest way for optical and selective control of the magnetization dynamics in alloys. Saliently, our results signify why various experiments demonstrating OISTR might obtain conflicting results.

    Place, publisher, year, edition, pages
    American Physical SocietyAmerican Physical Society (APS), 2022
    National Category
    Condensed Matter Physics
    Identifiers
    urn:nbn:se:uu:diva-470544 (URN)10.1103/PhysRevB.105.L100401 (DOI)000766660100003 ()
    Funder
    Swedish Research Council, 2018-05973Swedish Foundation for Strategic Research , ICA16-0037Swedish Research Council, 2019-03901EU, European Research Council, 854843-FASTCORR
    Available from: 2022-03-28 Created: 2022-03-28 Last updated: 2025-01-24Bibliographically approved
    2. The interplay of local electron correlations and ultrafast spin dynamics in fcc Ni
    Open this publication in new window or tab >>The interplay of local electron correlations and ultrafast spin dynamics in fcc Ni
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    2023 (English)In: Materials Research Letters, E-ISSN 2166-3831, Vol. 11, no 8, p. 655-661Article in journal (Refereed) Published
    Abstract [en]

    The complex electronic structure of metallic ferromagnets is determined by a balance between exchange interaction, electron hopping leading to band formation, and local Coulomb repulsion. By combining high energy and temporal resolution in femtosecond time-resolved X-ray absorption spectroscopy with ab initio time-dependent density functional theory we analyze the electronic structure in fcc Ni on the time scale of these interactions in a pump-probe experiment. We distinguish transient broadening and energy shifts in the absorption spectra, which we demonstrate to be captured by electron repopulation respectively correlation-induced modifications of the electronic structure, requiring to take the local Coulomb interaction into account.

    Place, publisher, year, edition, pages
    Taylor & Francis, 2023
    Keywords
    Ferromagnetism, local correlations, ultrafast dynamics, time-resolved x-ray absorption spectroscopy, time-dependent density functional theory
    National Category
    Atom and Molecular Physics and Optics Condensed Matter Physics
    Identifiers
    urn:nbn:se:uu:diva-504198 (URN)10.1080/21663831.2023.2210606 (DOI)000986736800001 ()
    Funder
    Swedish Research Council, 2018-05973Swedish Foundation for Strategic Research, ICA16-0037Swedish Research Council, 2019-03901EU, European Research Council, 854843 - FASTCORRKnut and Alice Wallenberg FoundationSwedish Research CouncilSwedish Foundation for Strategic Research
    Available from: 2023-06-12 Created: 2023-06-12 Last updated: 2025-03-19Bibliographically approved
    3. Optically controlling the competition between spin flips and intersite spin transfer in a Heusler half-metal on sub-100-fs time scales
    Open this publication in new window or tab >>Optically controlling the competition between spin flips and intersite spin transfer in a Heusler half-metal on sub-100-fs time scales
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    2023 (English)In: Science Advances, E-ISSN 2375-2548, Vol. 9, no 45, article id eadi1428Article in journal (Refereed) Published
    Abstract [en]

    The direct manipulation of spins via light may provide a path toward ultrafast energy-efficient devices. However, distinguishing the microscopic processes that can occur during ultrafast laser excitation in magnetic alloys is challenging. Here, we study the Heusler compound Co2MnGa, a material that exhibits very strong light-induced spin transfers across the entire M-edge. By combining the element specificity of extreme ultraviolet high-harmonic probes with time-dependent density functional theory, we disentangle the competition between three ultrafast light-induced processes that occur in Co2MnGa: same-site Co-Co spin transfer, intersite Co-Mn spin transfer, and ultrafast spin flips mediated by spin-orbit coupling. By measuring the dynamic magnetic asymmetry across the entire M-edges of the two magnetic sublattices involved, we uncover the relative dominance of these processes at different probe energy regions and times during the laser pulse. Our combined approach enables a comprehensive microscopic interpretation of laser-induced magnetization dynamics on time scales shorter than 100 femtoseconds.

    Place, publisher, year, edition, pages
    American Association for the Advancement of Science (AAAS), 2023
    National Category
    Condensed Matter Physics Atom and Molecular Physics and Optics
    Identifiers
    urn:nbn:se:uu:diva-523905 (URN)10.1126/sciadv.adi1428 (DOI)001142520500002 ()37948525 (PubMedID)
    Funder
    Swedish Foundation for Strategic Research, ICA16-0037Swedish Research Council, 2019-03901Swedish Research Council, 2016-05980Swedish Research Council, 2019-05304Swedish Research Council, 2022.0108Swedish Research Council, 854843-FASTCORRKnut and Alice Wallenberg Foundation, 2022-06725Knut and Alice Wallenberg Foundation, 2018-05973Knut and Alice Wallenberg Foundation, 2018.0060Knut and Alice Wallenberg FoundationEU, European Research Council, 2021.0246StandUpSwedish National Infrastructure for Computing (SNIC)
    Available from: 2024-02-26 Created: 2024-02-26 Last updated: 2025-01-24Bibliographically approved
    4. How to Measure and Model Light-Induced Spin Transfer
    Open this publication in new window or tab >>How to Measure and Model Light-Induced Spin Transfer
    (English)Manuscript (preprint) (Other academic)
    National Category
    Condensed Matter Physics
    Identifiers
    urn:nbn:se:uu:diva-548288 (URN)10.48550/arXiv.2501.12416 (DOI)
    Available from: 2025-01-23 Created: 2025-01-23 Last updated: 2025-01-24
    5. How quantum selection rules influence the magneto-optical effects of driven, ultrafast magnetization dynamics
    Open this publication in new window or tab >>How quantum selection rules influence the magneto-optical effects of driven, ultrafast magnetization dynamics
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Ultrafast magnetization dynamics driven by ultrashort pump lasers is typically explained by changes in electronic populations and scattering pathways of excited conduction electrons. This conventional approach overlooks the fundamental role of quantum mechanical selection rules, governing transitions from core states to the conduction band, that forms the key method of the probing step in these experiments. By employing fully ab initio time-dependent density functional theory, we reveal that these selection rules profoundly influence the interpretation of ultrafast spin dynamics at specific probe energies. Our analysis for hcp Co and fcc Ni at the M edge demonstrates that the transient dynamics, as revealed in pump-probe experiments, arise from a complex interplay of optical excitations of the M shell. Taking into account the selection rules and conduction electron spin flips, this leads to highly energy-dependent dynamics. These findings address longstanding discrepancies in experimental TMOKE measurements and show that only through meticulous consideration of matrix elements at the probe stage, can one ensure that magnetization dynamics is revealed in its true nature, instead of being muddled by artifacts arising from the choice of probe energy.

    National Category
    Condensed Matter Physics
    Identifiers
    urn:nbn:se:uu:diva-547939 (URN)10.48550/arXiv.2501.05433 (DOI)
    Funder
    Swedish Research Council Formas
    Available from: 2025-01-20 Created: 2025-01-20 Last updated: 2025-01-24
    6. Different fingerprints for the OISTR mechanism in the magnetic alloys experiments
    Open this publication in new window or tab >>Different fingerprints for the OISTR mechanism in the magnetic alloys experiments
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    2022 (English)In: ADVANCES IN ULTRAFAST CONDENSED PHASE PHYSICS III / [ed] Haacke, S Yakovlev, V, SPIE - The International Society for Optics and Photonics, 2022, Vol. 12132, article id 121320BConference paper, Published paper (Refereed)
    Abstract [en]

    The interplay between various degrees of freedom in laser induced ultrafast magnetization dynamics (LIUMD) of magnetic alloys is intricate due to the competition between different mechanisms and processes. In this work, we resolve the element specific magnetization dynamics of FePd alloy and further elucidate the dependency of the OISTR mechanism on the laser pulse parameters using ultrashort, short and relatively longer pulse duration with weak and strong fluence. Remarkably, our results illustrate potential discrepancies in experiments measuring the optical inter site spin transfer (OISTR) effect in magnetic alloys.

    Place, publisher, year, edition, pages
    SPIE - The International Society for Optics and Photonics, 2022
    Series
    Proceedings of SPIE, ISSN 0277-786X, E-ISSN 1996-756X
    Keywords
    ultrafast magnetization dynamics, spin flips, magnetic alloys, LIUMD, OISTR, SOC
    National Category
    Condensed Matter Physics Atom and Molecular Physics and Optics
    Identifiers
    urn:nbn:se:uu:diva-484241 (URN)10.1117/12.2621839 (DOI)000844424500008 ()978-1-5106-5141-8 (ISBN)978-1-5106-5140-1 (ISBN)
    Conference
    Conference on Advances in Ultrafast Condensed Phase Physics III, APR 03-MAY 20, 2022, ELECTR NETWORK
    Funder
    Swedish Research Council, 2018-05973Swedish Foundation for Strategic Research, ICA160037Swedish Research Council, 2019-03901EU, European Research Council, 854843-FASTCORR
    Available from: 2022-09-12 Created: 2022-09-12 Last updated: 2025-02-05
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    UUThesis_ Elhanoty,M-2025
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  • Public defence: 2025-03-28 09:00 Lectura hall Sonja Lyttkens, Uppsala
    Aydin, Abuzer Orkun
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Regulation of Substrate Water Access in Photosynthetic Oxygen Evolution2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Photosystem II (PSII) is a membrane protein complex that catalyzes the light-driven oxidation of water, forming the molecular oxygen indispensable to life on Earth. The goal of this thesis is to elucidate how PSII orchestrates water delivery at its oxygen-evolving complex (OEC) through finely tuned protein–cofactor–water networks. Five interconnected projects employ a range of structural and spectroscopic techniques—including serial femtosecond crystallography (SFX), high-resolution cryo-electron microscopy (cryo-EM), time-resolved membrane inlet mass spectrometry (TR-MIMS), EPR spectroscopy, and in-vivo variable fluorescence—to reveal key mechanistic steps in water oxidation.

    Project I captures the final S3→[S4]→S0 transition of the Kok cycle using time-resolved SFX, unveiling a two-step Mn4CaO5–Ox cluster reduction and a potential peroxidic intermediate. Project II uses cryo-EM to resolve a 1.71 Å resolution light-activated structure of Thermosynechococcus vestitus PSII, revealing crucial proton and water positions, clarifying the mechanism of two-step QB reduction, and reinforcing the role of the O1-channel as a primary substrate route. Project III reevaluates a two-site two-conformation exchange model to reconcile O5 as the slowly exchanging substrate, emphasizing how the conformational equilibrium of the Mn4CaO5 cluster dictates kinetics. Project IV settles the debate over O1-channel accessibility in Synechocystis sp. PCC 6803 PSII by showing that site-directed mutations in channel bottleneck residues diminish substrate water exchange efficiency. Finally, Project V presents a unifying framework for multi-step substrate exchange, exemplified by the D1-N298A mutation’s differential impact on S2- and S3-state kinetics; this mutation disrupts N298 hydrogen-bond network in the O1-terminal cavity, impairing YZ oxidation and specifically slowing substrate exchange in the S3 state.

    Together, these studies demonstrate how well-defined channels, protein hydrogen-bonding motifs, and water clusters collectively govern PSII’s water oxidation. By integrating diverse methodological approaches, the thesis reveals the centrality of protein–water dynamics in regulating the substrate water molecule management in the OEC. The findings refine current mechanistic models of O–O bond formation, laying a foundation for future research into the design of bioinspired catalysts and further explorations of nature’s remarkable water-splitting machinery.

    List of papers
    1. Structural evidence for intermediates during O2 formation in photosystem II
    Open this publication in new window or tab >>Structural evidence for intermediates during O2 formation in photosystem II
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    2023 (English)In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 617, no 7961, p. 629-636Article in journal (Refereed) Published
    Abstract [en]

    In natural photosynthesis, the light-driven splitting of water into electrons, protons and molecular oxygen forms the first step of the solar-to-chemical energy conversion process. The reaction takes place in photosystem II, where the Mn4CaO5 cluster first stores four oxidizing equivalents, the S0 to S4 intermediate states in the Kok cycle, sequentially generated by photochemical charge separations in the reaction center and then catalyzes the O–O bond formation chemistry1,2,3. Here, we report room temperature snapshots by serial femtosecond X-ray crystallography to provide structural insights into the final reaction step of Kok’s photosynthetic water oxidation cycle, the S3→[S4]→S0 transition where O2 is formed and Kok’s water oxidation clock is reset. Our data reveal a complex sequence of events, which occur over micro- to milliseconds, comprising changes at the Mn4CaO5 cluster, its ligands and water pathways as well as controlled proton release through the hydrogen-bonding network of the Cl1 channel. Importantly, the extra O atom Ox, which was introduced as a bridging ligand between Ca and Mn1 during the S2→S3 transition4,5,6, disappears or relocates in parallel with Yz reduction starting at approximately 700 μs after the third flash. The onset of O2 evolution, as indicated by the shortening of the Mn1–Mn4 distance, occurs at around 1,200 μs, signifying the presence of a reduced intermediate, possibly a bound peroxide.

    Place, publisher, year, edition, pages
    Springer Nature, 2023
    National Category
    Biochemistry Molecular Biology
    Research subject
    Biology with specialization in Structural Biology
    Identifiers
    urn:nbn:se:uu:diva-502685 (URN)10.1038/s41586-023-06038-z (DOI)000991687000024 ()37138085 (PubMedID)
    Funder
    NIH (National Institutes of Health)Swedish Research Council, 2016-05183Swedish Energy Agency, 45421-1
    Available from: 2023-05-29 Created: 2023-05-29 Last updated: 2025-02-20Bibliographically approved
    2. Cryo-electron microscopy reveals hydrogen positions and water networks in photosystem II
    Open this publication in new window or tab >>Cryo-electron microscopy reveals hydrogen positions and water networks in photosystem II
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    2024 (English)In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 384, no 6702, p. 1349-1355Article in journal (Refereed) Published
    Abstract [en]

    Photosystem II starts the photosynthetic electron transport chain that converts solar energy into chemical energy and thus sustains life on Earth. It catalyzes two chemical reactions: water oxidation to molecular oxygen and plastoquinone reduction. Coupling of electron and proton transfer is crucial for efficiency; however, the molecular basis of these processes remains speculative owing to uncertain water binding sites and the lack of experimentally determined hydrogen positions. We thus collected high-resolution cryo-electron microscopy data of fully hydrated photosystem II from the thermophilic cyanobacterium Thermosynechococcus vestitus to a final resolution of 1.71 angstroms. The structure reveals several previously undetected partially occupied water binding sites and more than half of the hydrogen and proton positions. This clarifies the pathways of substrate water binding and plastoquinone B protonation.

    Place, publisher, year, edition, pages
    American Association for the Advancement of Science (AAAS), 2024
    National Category
    Organic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-540660 (URN)10.1126/science.adn6541 (DOI)001273959200032 ()38900892 (PubMedID)
    Funder
    Knut and Alice Wallenberg FoundationSwedish Research Council, 2020-03809Familjen Erling-Perssons StiftelseThe Kempe Foundations, JCK-2030 2021-2023Science for Life Laboratory, SciLifeLabCarl Tryggers foundation , CTS 19.324
    Available from: 2024-10-21 Created: 2024-10-21 Last updated: 2025-02-10Bibliographically approved
    3. Probing substrate water access through the O1 channel of Photosystem II by single site mutations and membrane inlet mass spectrometry
    Open this publication in new window or tab >>Probing substrate water access through the O1 channel of Photosystem II by single site mutations and membrane inlet mass spectrometry
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    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Light-driven water oxidation by photosystem II sustains life on Earth by providing the electrons and protons for the reduction of CO2 to carbohydrates and the molecular oxygen we breathe. The inorganic core of the oxygen evolving complex is made of the earth-abundant elements manganese, calcium and oxygen (Mn4CaO5 cluster), and is situated in a binding pocket that is connected to the aqueous surrounding via water-filled channels that allow water intake and proton egress. Recent serial crystallography and infrared spectroscopy studies performed with PSII isolated from Thermosynechococcus vestitus (T. vestitus) support that one of these channels, the O1 channel, facilitates water access to the Mn4CaO5 cluster during its S2 - S3 and S3 - S4 - S0 state transitions, while a subsequent CryoEM study concluded that this channel is blocked in the cyanobacterium Synechocystis sp. PCC 6803, questioning the role of the O1 channel in water delivery. Employing site-directed mutagenesis we modified the two O1 channel bottleneck residues D1-E329 and CP43-V410 (T. vestitus numbering) and probed water access and substrate exchange via time resolved membrane inlet mass spectrometry. Our data demonstrates that water reaches the Mn4CaO5 cluster via the O1 channel in both wildtype and mutant PSII. In addition, the detailed analysis provides functional insight into the intricate protein-water-cofactor network near the Mn4CaO5 cluster that includes the pentameric, near planar ‘water wheel’ of the O1 channel.  

    National Category
    Biophysics
    Research subject
    Biochemistry
    Identifiers
    urn:nbn:se:uu:diva-549812 (URN)
    Funder
    Swedish Research Council, 2020-03809Swedish Research Council, 2024-04804
    Available from: 2025-02-09 Created: 2025-02-09 Last updated: 2025-02-10Bibliographically approved
    4. On the simulation and interpretation of substrate-water exchange experiments in photosynthetic water oxidation
    Open this publication in new window or tab >>On the simulation and interpretation of substrate-water exchange experiments in photosynthetic water oxidation
    2024 (English)In: Photosynthesis Research, ISSN 0166-8595, E-ISSN 1573-5079, Vol. 162, no 2-3, p. 413-426Article in journal (Refereed) Published
    Abstract [en]

    Water oxidation by photosystem II (PSII) sustains most life on Earth, but the molecular mechanism of this unique process remains controversial. The ongoing identification of the binding sites and modes of the two water-derived substrate oxygens (‘substrate waters’) in the various intermediates (Si states, i = 0, 1, 2, 3, 4) that the water-splitting tetra-manganese calcium penta-oxygen (Mn4CaO5) cluster attains during the reaction cycle provides central information towards resolving the unique chemistry of biological water oxidation. Mass spectrometric measurements of single- and double-labeled dioxygen species after various incubation times of PSII with H218O provide insight into the substrate binding modes and sites via determination of exchange rates. Such experiments have revealed that the two substrate waters exchange with different rates that vary independently with the Si state and are hence referred to as the fast (Wf) and the slow (WS) substrate waters. New insight for the molecular interpretation of these rates arises from our recent finding that in the S2 state, under special experimental conditions, two different rates of WS exchange are observed that appear to correlate with the high spin and low spin conformations of the Mn4CaO5 cluster. Here, we reexamine and unite various proposed methods for extracting and assigning rate constants from this recent data set. The analysis results in a molecular model for substrate-water binding and exchange that reconciles the expected non-exchangeability of the central oxo bridge O5 when located between two Mn(IV) ions with the experimental and theoretical assignment of O5 as WS in all S states. The analysis also excludes other published proposals for explaining the water exchange kinetics.

    Place, publisher, year, edition, pages
    Springer, 2024
    Keywords
    Photosystem II, Oxygen-evolving complex, Mechanism of water oxidation, Membrane inlet mass spectrometry (MIMS), Substrate-water exchange
    National Category
    Biophysics
    Research subject
    Biochemistry
    Identifiers
    urn:nbn:se:uu:diva-548704 (URN)10.1007/s11120-024-01084-8 (DOI)001190065600001 ()38512410 (PubMedID)
    Funder
    Swedish Research Council, 2020-03809
    Available from: 2025-01-28 Created: 2025-01-28 Last updated: 2025-02-13Bibliographically approved
    5. The Role of D1-N298 in Regulating Substrate Water Exchange and Protein-Water Dynamics in Photosystem II
    Open this publication in new window or tab >>The Role of D1-N298 in Regulating Substrate Water Exchange and Protein-Water Dynamics in Photosystem II
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Photosystem II (PSII) catalyzes the water-splitting reaction during photosynthesis, generating oxygen, protons, and electrons through the multi-step S state cycle. The role of protein residues in maintaining the intricate dynamics of substrate water exchange within the Mn4CaO5 cluster remains a critical area of research. In this study, we investigate the effects of the D1-N298A mutation on water exchange kinetics in PSII core complexes. Comparing wild-type (WT) PSII to the mutant, we observed that the mutation significantly slows the exchange of both substrate waters in the S3-state, while leaving the slow S2 state exchange kinetics largely unaffected. Our results suggest that the D1-N298 residue plays a vital role in maintaining the hydrogen-bond network within the O1 channel, which facilitates both proton-coupled electron transfer (PCET) during S state turnover and substrate water exchange. The disruption of the YZ-H190-N298 triad by the D1-N298A mutation is proposed to alter the structural organization of the waterwheel, raising the activation energy for Mn1 reduction by YZ and impairing protonation and deprotonation processes. These findings reinforce the hypothesis that water molecules introduced via the O1 channel, such as Wx or W3, act as the fast-exchanging substrate in the S2 state and become Ox/O6 in the S3 state, forming the O–O bond with the slowly-exchanging substrate identified previously as the central µ3-oxo bridge O5.

    National Category
    Biophysics
    Research subject
    Biochemistry
    Identifiers
    urn:nbn:se:uu:diva-549813 (URN)
    Available from: 2025-02-09 Created: 2025-02-09 Last updated: 2025-02-10
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  • Public defence: 2025-03-28 10:15 Geijersalen, Uppsala
    Leibring Svedjedal, Carin
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Languages, Department of Scandinavian Languages.
    Att vara och göra trans: Diskurser om kön och transidentiteter i transpersoners egenvalda självbenämningar och svensk medierapportering 2019‒20232025Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This dissertation examines discourses about gender and identity among transgender people. Defining a discourse as a linguistic construction of knowledge that is negotiated, established or positioned as taken for granted within a specific historical, social, cultural and societal context, I aim to analyze how discourses about gender and identity are shaped within and beyond the perspectives of transgender people, and how transgender identities are currently enabled or limited in Swedish society. I analyze two bodies of material in order to provide insights into gender and identity among transgender people in Sweden. Through mediated discourse analysis, I analyze transgender people’s self-chosen designations (first names and pronouns), and through critical discourse analysis, I analyze legitimizations of transgender-related topics in Swedish news media during 2019–2023. Both bodies of material are also analyzed in terms of their affective action, in order to give a broader perspective on how self-chosen designations and media texts can be understood in light of how discourses about gender and identity are created. 

    The results show how discourses of gender and identity vary depending on whether they are constructed within or outside the group. This variation prevails in terms of the renegotiation of gender and identity and the societal view of gender. Within the group, the discourses, and renegotiations of gender, and the societal view of it adopt an individual and flexible perspective on what it means to be and do transgender, with mental gender in focus and room for renegotiation. Outside the group, however, the discourses, renegotiations and social views are instead governed by the framework of a so-called cisbinary matrix, in which biological gender is considered more or less synonymous with gender belonging, which ultimately limits renegotiations and makes them difficult, along with, to quote parts of the dissertation’s material, “new” views on gender (i.e. the idea that gender is based on a mental experience). Overall, the dissertation provides evidence of how transgender people, based on their individual perspectives on gender and identity, resist and renegotiate the conditions under which their experiences and identities can be accommodated alongside those of people who fall within the cisbinary structures.

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  • Public defence: 2025-03-28 13:00 H:son Holmdahlsalen, Uppsala
    Smekal, Anna-Karin
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care.
    Antibiotic concentrations in the ICU2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Severe infections are life-threatening conditions and common cause of emergency admission to intensive care units (ICU). Initial adequate antibiotic treatment is known to be crucial for the outcome. However, mortality and morbidity remain high.

    The overall aim of this thesis was to investigate strategies for optimising antibiotic concentrations, pharmacokinetic/pharmacodynamic (PK/PD) target fulfilment and dosing in ICU patients during the early phase of infection.

    In a prospective multi-centre study on the first 72 h of treatment with one of three β-lactams, cefotaxime, piperacillin-tazobactam or meropenem, 138 ICU patients were included.

    We found a high proportion of ICU patients not reaching the PK/PD targets suggested by European experts. Younger age, signs of augmented renal clearance, treatment with cefotaxime, and non-urinary tract infections were identified as risk factors for target failure where early therapeutic drug monitoring (TDM) could be encouraged.

    When further investigating the impact of different minimum inhibitory concentration (MIC) parameters on the PK/PD target attainment, the current use of  MICWCS,  based on the bacterial worst case scenario (WCS), instead of the MICECOFF (epidemiological cut-off (ECOFF)) based on the actual causative bacterial pathogen was found to overestimate target failure with risk of overdosing.

    In predictions of target attainment using different infusion durations, we found that target attainment rates for primary pathogen scenarios were high regardless of infusion type, indicating that short infusion (SI) is sufficient in most community-acquired infections except for infections with S. aureus treated with cefotaxime, where a higher daily dose than 6 g is needed. In WCS-pathogens, reflecting infections with P. aeruginosa, SI was insufficient and routine use of extended (EI) or continuous (CI) infusions could be beneficial for piperacillin-tazobactam and meropenem. However, the risk of toxicity might increase and individualised TDM is warranted.

    In a retrospective single-centre study of 255 ICU patients treated with gentamicin, the use of estimated gentamicin clearance CL derived from measured 8 h concentrations was found to be a potential exogenous marker of renal function in patients in an early phase of the severe infection which could improve dosing of renally eliminated drugs like the β-lactams.

    List of papers
    1. Low attainment to PK/PD-targets for β-lactams in a multi-center study on the first 72 h of treatment in ICU patients
    Open this publication in new window or tab >>Low attainment to PK/PD-targets for β-lactams in a multi-center study on the first 72 h of treatment in ICU patients
    2022 (English)In: Scientific Reports, E-ISSN 2045-2322, Vol. 12, no 1, article id 21891Article in journal (Refereed) Published
    Abstract [en]

    Severe infections are life-threatening conditions commonly seen in the intensive care units (ICUs). Antibiotic treatment with adequate concentrations is of great importance during the first days when the bacterial load is the highest. Therapeutic drug monitoring (TDM) of β-lactam antibiotics has been suggested to monitor target attainment and to improve the outcome. This prospective multi-center study in seven ICUs in Sweden investigated pharmacokinetic/pharmacodynamic-target (PK/PD-target) attainment for cefotaxime, piperacillin-tazobactam and meropenem, commonly used β-lactams in Sweden. A mid-dose and trough antibiotic concentration blood sample were taken from patients with severe infection daily during the first 72 h of treatment. Antibiotic plasma concentrations were analysed by liquid chromatography-mass spectrometry (LC–MS). Antibiotic concentrations 100% time above MIC (minimal inhibitory concentration), (100% T > MIC) and four times above MIC 50% of the time (50% T > 4xMIC) were used as PK/PD-targets. We included 138 patients with the median age of 67 years and the median Simplified Acute Physiology Score 3 (SAPS3) of 59. Forty-five percent of the study-population failed to reach 100% T > MIC during the first day of treatment. The results were similar the following two days. There was a three-fold risk of not meeting the PK/PD target if the patient was treated with cefotaxime. For the cefotaxime treated patients 8 out of 55 (15%) had at least one end-dose concentrations below the level of detection during the study. Low age, low illness severity, low plasma creatinine, lower respiratory tract infection and cefotaxime treatment were risk factors for not reaching 100% T > MIC. In Swedish ICU-patients treated with β-lactam antibiotics, a high proportion of patients did not reach the PK/PD target. TDM could identify patients that need individual higher dosing regimens already on the first day of treatment. Further studies on optimal empirical start dosing of β-lactams, especially for cefotaxime, in the ICU are needed.

    Place, publisher, year, edition, pages
    Springer Nature, 2022
    National Category
    Infectious Medicine Anesthesiology and Intensive Care
    Identifiers
    urn:nbn:se:uu:diva-506904 (URN)10.1038/s41598-022-25967-9 (DOI)000971311200030 ()36535989 (PubMedID)
    Funder
    Region Stockholm, ALF20190536Uppsala UniversityStiftelsen Familjen Olinder-Nielsens fond för infektionsmedicinsk forskningVinnova
    Note

    Title in Web of Science: Low attainment to PK/PD-targets for beta-lactams in a multi-center study on the first 72 h of treatment in ICU patients

    Available from: 2023-07-03 Created: 2023-07-03 Last updated: 2025-02-09Bibliographically approved
    2. Swedish multicentre study of target attainments with β-lactams in the ICU: which MIC parameter should be used?
    Open this publication in new window or tab >>Swedish multicentre study of target attainments with β-lactams in the ICU: which MIC parameter should be used?
    2023 (English)In: Journal of Antimicrobial Chemotherapy, ISSN 0305-7453, E-ISSN 1460-2091, Vol. 78, no 12, p. 2895-2901Article in journal (Refereed) Published
    Abstract [en]

    Background

    Therapeutic drug monitoring (TDM) has been suggested to optimize antimicrobial target attainment, typically using 100%T>MIC, in β-lactam treatment in the ICU. The MIC parameter used in this equation is mostly the worst case scenario MIC (MICWCS)—the highest MIC the empirical treatment should cover. However, the impact of the MIC parameter used in pharmacokinetic/pharmacodynamic calculations has been poorly investigated.

    Objectives

    To assess the influence of target attainment rates for two different MIC parameters using actual MICs of the causative pathogens as the primary reference.

    Methods

    In a Swedish multicentre study of target attainment for 138 ICU patients treated with β-lactams, the causative pathogen was isolated and subjected to reference MIC testing. Whenever the strain belonged to the WT distribution, we assigned it to the category MICECOFF (epidemiological cut-off value). In the calculations we compared the MICECOFF and the MICWCS.

    Results

    The proportion of patients with target attainment failure for all antibiotics using 100%T>MIC was 45% (95% CI, 37%–53%) for MICWCS and 23% (95% CI, 16%–31%) for MICECOFF. When the target 50%T>4×MIC was used, corresponding attainment failures were 57% (95% CI, 49%–66%) and 25% (95% CI, 17%–32%) for MICWCS and MICECOFF, respectively.

    Conclusions

    MICWCS can overestimate target attainment failure. The use of MICWCS could be one reason for the difficulties in establishing a relationship between target failure and mortality in other studies. Based on findings herein, the MICECOFF, which is based on the MIC of the causative pathogen, should be considered a more suitable alternative. When no pathogen is detected, the MICECOFF of likely pathogens according to infection type should be used.

    Place, publisher, year, edition, pages
    Oxford University Press, 2023
    National Category
    Clinical Medicine Anesthesiology and Intensive Care
    Identifiers
    urn:nbn:se:uu:diva-516570 (URN)10.1093/jac/dkad327 (DOI)001094167000001 ()37897332 (PubMedID)
    Funder
    Uppsala University
    Available from: 2023-11-24 Created: 2023-11-24 Last updated: 2025-02-09Bibliographically approved
    3. Short, extended and continuous infusion of β-lactams: predicted impact on target attainment and risk for toxicity in an ICU patient cohort.
    Open this publication in new window or tab >>Short, extended and continuous infusion of β-lactams: predicted impact on target attainment and risk for toxicity in an ICU patient cohort.
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    2025 (English)In: Journal of Antimicrobial Chemotherapy, ISSN 0305-7453, E-ISSN 1460-2091, article id dkaf013Article in journal (Refereed) Epub ahead of print
    Abstract [en]

    OBJECTIVES: This study aimed to predict the impact of different infusion strategies on pharmacokinetic/pharmacodynamic (PK/PD) target attainment and the potential risk for toxicity in an ICU cohort treated with β-lactams.

    METHOD: Using collected patient data from 137 adult ICU patients, and applying population PK models, individual PK parameters were estimated and used to predict concentrations and target attainment following cefotaxime 2 g q8h, piperacillin/tazobactam 4.5 g q6h and meropenem 1 g q8h, applying 15 min short infusions (SI), 3 h extended infusions (EI) and 24 h continuous infusion (CI). The MIC level of the most common primary pathogens, and the worst-case scenario (WCS) pathogen, were used in analyses.

    RESULTS: For primary pathogens, target was reached in 94% (129/137) using SI. For WCS pathogens treated with piperacillin/tazobactam and meropenem, 78% (65/83) and 92% (76/83) reached target using SI and EI, respectively. However, target attainment was lower for cefotaxime [SI: 31% (17/54), EI: 44% (24/54)]. Overall, the number of individuals with potentially toxic concentrations was low, both in EI (n = 7) and SI (n = 5). For CI and WCS, target was reached in 50% (27/54), 96% (54/56) and 93% (25/27) for cefotaxime, piperacillin/tazobactam and meropenem, respectively.

    CONCLUSIONS: In a Swedish ICU cohort target attainment rates for primary pathogens were high regardless of infusion strategy. In WCS pathogens, SI was insufficient, suggesting the benefit of routine use of EI or CI. However, for cefotaxime, target attainment remained low also with EI and CI. The use of CI might lead to unnecessarily high concentrations, but well-established toxicity levels are lacking and future studies are warranted.

    National Category
    Infectious Medicine
    Identifiers
    urn:nbn:se:uu:diva-549839 (URN)10.1093/jac/dkaf013 (DOI)39847494 (PubMedID)
    Available from: 2025-02-09 Created: 2025-02-09 Last updated: 2025-02-09
    4. Can gentamicin concentrations be used to estimate glomerular filtration rate in intensive care unit patients?
    Open this publication in new window or tab >>Can gentamicin concentrations be used to estimate glomerular filtration rate in intensive care unit patients?
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Infectious Medicine
    Identifiers
    urn:nbn:se:uu:diva-549840 (URN)
    Available from: 2025-02-09 Created: 2025-02-09 Last updated: 2025-02-09
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  • Public defence: 2025-03-28 14:15 Humanistiska teatern, Uppsala
    Hölzlhammer, Lilli
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Languages, Department of Linguistics and Philology.
    Translating and Teaching: From the Arabic Kalila wa-Dimnah to the Byzantine Stephanites kai Ichnelates2025Doctoral thesis, monograph (Other academic)
    Abstract [en]

    In the late 11th century, Symeon Seth, a scholar from Antioch, dedicated a translation of the highly popular Arabic fable collection Kalila wa-Dimnah to the Byzantine Emperor Alexios I Komnenos. As a both educational and entertaining text, the translation Stephanites kai Ichnelates quickly spread in the Byzantine Empire. Yet, the lack of surviving Arabic manuscripts from before the 13th century, makes it hard to say how Symeon Seth’s translation changed its source text and how these changes affected the didactic content.

    This study therefore has a twofold aim. First, to reconstruct as closely as possible the connection between the Arabic sources and the Greek translation, and to rethink medieval translation practices. Second, to analyze the didactic techniques by which the text sets out to teach its readers.

    In addition, the close examination of manuscripts and Symeon Seth’s translation practices offer new methodological approaches. First, the comparison of manuscripts and other writings attributed to the same historical person can help constructing what in this study is termed a writing persona. Second, the analysis of didactic narratological devices employed in the text further the understanding of how texts attempt to educate their readers.

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  • Public defence: 2025-04-01 10:15 Lecture hall 2, Uppsala
    Chen, Hanfeng
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Economics.
    Rethinking Monetary Policy Transmission: Nonbank Finance, Central Bank Digital Currencies, and the Role of Bank Market Power2025Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Essay I I study the transmission of monetary policy through banks and nonbank financial intermediaries (NBFIs) in the United States. First, I construct a dataset on nonbank financial intermediation that accounts for the various linkages between financial intermediaries. I empirically demonstrate that following monetary policy tightenings, U.S. households substitute bank deposits with nonbank-created liquidity. Bank lending contracts while nonbank intermediation expands. Second, to explain these empirical findings, I develop a New-Keynesian model incorporating both banks and nonbanks. Banks face a liquidity constraint that limits their ability to issue debt, a restriction that nonbanks do not encounter. As the policy rate rises, banks keep their deposit rates relatively low while nonbanks increase the returns on their liabilities in tandem with the policy rate. This generates the household portfolio rebalancing and the shift toward nonbank finance observed in the data. Moreover, I show that in the absence of nonbank financial intermediation, the economic contraction following a monetary tightening is deeper. These findings suggest that the presence of NBFIs weakens the effect of monetary policy.   

    Essay II (with Matthias Hänsel and Hiep Nguyen): Interest rates on new central bank digital currencies (CBDCs) can be expected to enter the monetary policy toolkit soon. Using an extended Sidrauski (1967) model featuring an oligopsonistic banking sector, we study the complex transmission of interest rates on CBDC, which generally involve both direct and indirecteffects. This is because a CBDC rate cut does not only affect the rate on the CBDC itself, but also induces the non-competitive deposit providers to adjust their spreads, as the new substitute for their products becomes relatively less attractive. A calibration exercise suggests that the indirect effects depend strongly on the sources of deposit market power: If driven by high concentration, they substantially amplify the aggregate effects of the CBDC policy rate, both in response to transitory shocks as well as regarding its long-run welfare effects. This contrasts them with policies directed at the banking sector which are weakened by a less competitive deposit market.

    Essay III (with Maria Elena Filippin): We examine the risks to bank intermediation following the introduction of a central bank digital currency (CBDC). In our framework, CBDC competes with commercial bank deposits as a household liquidity source, and commercial banks can secure central bank funding by posting collateral. First, we revisit the equivalence results of Brunnermeier and Niepelt (2019) and Niepelt (2022). We show that the central bank can, even in the presence of a collateral constraint, ensure the same equilibrium allocation and price system following the introduction of a CBDC by offering loans to banks. However, to access the loans, banks must hold collateral at the expense of extending credit to firms. Thus, while the government can ensure that the introduction of CBDC has no real effects on the economy, it does not guarantee "full neutrality" as the portfolio and policy changes affect banks' business models. Second, we study the dynamic responses of the economy to a near-permanent increase in CBDC, without imposing equivalence. In this case, we find that the introduction of CBDC need not disintermediate banks, but could in fact expand the banks' credit to firms.

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  • Public defence: 2025-04-01 12:00 room A1:107a, Uppsala
    Bao, Letian
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Molecular Biology.
    Tuning the Ribosome: Roles of Ribosomal RNA Modifications and Substrates Revealed by Speeding Up and Slowing Down Catalysis2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The peptidyl transferase center (PTC) of the ribosome catalyzes peptidyl transfer and release. It consists of domain V of the 23S ribosomal RNA and it is heavily modified by RNA modification enzymes, suggesting these modifications are functionally important. However, individual knockouts (KO) of the enzymes have minimal impacts on bacteria growth, except a two to fourfold deficit for rlmE. To study the significance of the rRNA modifications on cell viability, combinations of KOs are needed. Our collaboratio succeeded in constructing the rluC/rlmE E. coli strain which showed the most severe phenotype yet seen at 37℃ and was lethal at 20℃, suggesting conditional essentiality of the rRNA modification enzymes. Furthermore, an early in vitro reconstitution with 23S rRNA lacking modifications around the PTC “critical region” showed catalytically inert 50S. However, our collaboration constructed a strain with all identified critical region modification enzymes KOed. This strain was viable and displayed a minimal growth deficit at 37℃, suggesting plasticity of the enzymes modifying around the PTC. Although the phenotypes of these KO strains have been well characterized, the molecular explanations for such deficits remain unclear. Here, based on biochemical approaches, I pinpoint that the enzyme KOs affect ribosome assembly and translocation, rather than peptide bond formation or release, in the two combined KO strains. These results clarify the importance and roles of the enigmatic rRNA modifications.

    Release is also catalyzed by PTC and understanding the rate-limiting step can help genetic engineering, as readthrough of a stop codon enables the incorporation of unnatural amino acids and treatment of genetic diseases. Although the rate-limiting step was suggested to be hydrolysis at physiological pH, the evidence was indirect. Here, I used fluorine-modified amino acids to activate the ester electrophile. Acceleration of the release reaction with activated ester at lower pHs provides direct evidence for rate-limiting hydrolysis.

    Mechanistic studies of peptidyl transfer and release were mainly based on the crystal structures of the 50S subunit. However, both model reactions on the 50S showed orders-of-magnitude slower rates than on the 70S, questioning their relevance. Here, I optimize the peptidyl transfer and release model reactions to near-physiological rates, though in organic solvents. A more physiological solution, achieved by substituting organic solvent with PEG, is found to best accelerate peptidyl transfer, but not release. These optimized reactions should aid analysis of the activities of synthetic ribosomes/PTCs and give insights into the evolution of ribosomes.

    List of papers
    1. Plasticity and conditional essentiality of modification enzymes for domain V of Escherichia coli 23S ribosomal RNA
    Open this publication in new window or tab >>Plasticity and conditional essentiality of modification enzymes for domain V of Escherichia coli 23S ribosomal RNA
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    2022 (English)In: RNA: A publication of the RNA Society, ISSN 1355-8382, E-ISSN 1469-9001, Vol. 28, no 6, p. 796-807Article in journal (Refereed) Published
    Abstract [en]

    Escherichia coli rRNAs are post-transcriptionally modified at 36 positions but their modification enzymes are dispensable individually for growth, bringing into question their significance. However, a major growth defect was reported for deletion of the RlmE enzyme, which abolished a 2 ' O methylation near the peptidyl transferase center (PTC) of the 23S rRNA. Additionally, an adjacent 80-nt "critical region" around the PTC had to be modified to yield significant peptidyl transferase activity in vitro. Surprisingly, we discovered that an absence of just two rRNA modification enzymes is conditionally lethal (at 20 degrees C): RlmE and RluC. At a permissive temperature (37 degrees C), this double knockout was shown to abolish four modifications and be defective in ribosome assembly, though not more so than the RlmE single knockout. However, the double knockout exhibited an even lower rate of tripeptide synthesis than did the single knockout, suggesting an even more defective ribosomal translocation. A combination knockout of the five critical-region-modifying enzymes RluC, RlmKL, RlmN, RlmM, and RluE (not RlmE), which synthesize five of the seven critical-region modifications and 14 rRNA and tRNA modifications altogether, was viable (minor growth defect at 37 degrees C, major at 20 degrees C). This was surprising based on prior in vitro studies. This five-knockout combination had minimal effects on ribosome assembly and frameshifting at 37 degrees C, but greater effects on ribosome assembly and in vitro peptidyl transferase activity at cooler temperatures. These results establish the conditional essentiality of bacterial rRNA modification enzymes and also reveal unexpected plasticity of modification of the PTC region in vivo.

    Place, publisher, year, edition, pages
    Cold Spring Harbor Laboratory Press (CSHL)Cold Spring Harbor Laboratory, 2022
    Keywords
    E, coli, modification enzymes, rRNA, tRNA, translation
    National Category
    Biochemistry Molecular Biology
    Identifiers
    urn:nbn:se:uu:diva-475112 (URN)10.1261/rna.079096.121 (DOI)000793718200003 ()35260421 (PubMedID)
    Funder
    Swedish Research Council, 2011-5787Swedish Research Council, 2016-1Swedish Research Council, 2017-04148
    Available from: 2022-06-03 Created: 2022-06-03 Last updated: 2025-02-20Bibliographically approved
    2. Translational impacts of enzymes that modify ribosomal RNA around the peptidyl transferase centre
    Open this publication in new window or tab >>Translational impacts of enzymes that modify ribosomal RNA around the peptidyl transferase centre
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    2024 (English)In: RNA Biology, ISSN 1547-6286, E-ISSN 1555-8584, Vol. 21, no 1, p. 31-41Article in journal (Refereed) Published
    Abstract [en]

    Large ribosomal RNAs (rRNAs) are modified heavily post-transcriptionally in functionally important regions but, paradoxically, individual knockouts (KOs) of the modification enzymes have minimal impact on Escherichia coli growth. Furthermore, we recently constructed a strain with combined KOs of five modification enzymes (RluC, RlmKL, RlmN, RlmM and RluE) of the ‘critical region’ of the peptidyl transferase centre (PTC) in 23S rRNA that exhibited only a minor growth defect at 37°C (although major at 20°C). However, our combined KO of modification enzymes RluC and RlmE (not RluE) resulted in conditional lethality (at 20°C). Although the growth rates for both multiple-KO strains were characterized, the molecular explanations for such deficits remain unclear. Here, we pinpoint biochemical defects in these strains. In vitro fast kinetics at 20°C and 37°C with ribosomes purified from both strains revealed, counterintuitively, the slowing of translocation, not peptide bond formation or peptidyl release. Elongation rates of protein synthesis in vivo, as judged by the kinetics of β-galactosidase induction, were also slowed. For the five-KO strain, the biggest deficit at 37°C was in 70S ribosome assembly, as judged by a dominant 50S peak in ribosome sucrose gradient profiles at 5 mM Mg2+. Reconstitution of this 50S subunit from purified five-KO rRNA and ribosomal proteins supported a direct role in ribosome biogenesis of the PTC region modifications per se, rather than of the modification enzymes. These results clarify the importance and roles of the enigmatic rRNA modifications.

    Place, publisher, year, edition, pages
    Taylor & Francis, 2024
    Keywords
    Modification enzymes, ribosomal RNA, peptidyl transferase centre, E. coli, translation
    National Category
    Biochemistry Molecular Biology
    Identifiers
    urn:nbn:se:uu:diva-535474 (URN)10.1080/15476286.2024.2368305 (DOI)001261497000001 ()38952121 (PubMedID)
    Funder
    Swedish Research Council, 2017- 04148Carl Tryggers foundation Tore Nilsons Stiftelse för medicinsk forskningÅke Wiberg Foundation
    Available from: 2024-08-02 Created: 2024-08-02 Last updated: 2025-02-20Bibliographically approved
    3. Rate-limiting hydrolysis in ribosomal release reactions revealed by ester activation
    Open this publication in new window or tab >>Rate-limiting hydrolysis in ribosomal release reactions revealed by ester activation
    2022 (English)In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 28, no 11, article id 102509Article in journal (Refereed) Published
    Abstract [en]

    Translation terminates by releasing the polypeptide chain in one of two chemical reactions catalyzed by the ribosome. Release is also a target for engineering, as readthrough of a stop codon enables incorporation of unnatural amino acids and treatment of genetic diseases. Hydrolysis of the ester bond of peptidyl-tRNA requires conformational changes of both a class I release factor (RF) protein and the peptidyl transferase center of a large subunit rRNA. The rate-limiting step was proposed to be hydrolysis at physiological pH and an RF conformational change at higher pH, but evidence was indirect. Here, we tested this by activating the ester electrophile at the Escherichia coli ribosomal P site using a trifluorine-substituted amino acid. Quench-flow kinetics revealed that RF1-catalyzed release could be accelerated, but only at pH 6.2-7.7 and not higher pH. This provided direct evidence for rate-limiting hydrolysis at physiological or lower pH and a different rate limitation at higher pH. Additionally, we optimized RF-free release catalyzed by unacylated tRNA or the CCA trinucleotide (in 30% acetone). We determined that these two model release reactions, although very slow, were surprisingly accelerated by the trifluorine analog but to a different extent from each other and from RF-catalyzed release. Hence, hydrolysis was rate limiting in all three reactions. Furthermore, in 20% ethanol, we found that there was significant competition between fMet-ethyl ester formation and release in all three release reactions. We thus favor proposed mechanisms for translation termination that do not require a fully-negatively-charged OH nucleophile.

    Place, publisher, year, edition, pages
    Elsevier, 2022
    Keywords
    protein synthesis termination, release factor, ribosome, fluorinated amino acid, ester hydrolysis, tRNA
    National Category
    Biochemistry Molecular Biology
    Identifiers
    urn:nbn:se:uu:diva-490377 (URN)10.1016/j.jbc.2022.102509 (DOI)000886086000012 ()36300356 (PubMedID)
    Funder
    Swedish Research Council, 2017-04148
    Available from: 2022-12-15 Created: 2022-12-15 Last updated: 2025-02-20Bibliographically approved
    4. Fast peptide bond formation and releaseby the ribosomal large subunit
    Open this publication in new window or tab >>Fast peptide bond formation and releaseby the ribosomal large subunit
    (English)Manuscript (preprint) (Other academic)
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:uu:diva-549796 (URN)
    Available from: 2025-02-08 Created: 2025-02-08 Last updated: 2025-02-10
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  • Public defence: 2025-04-03 09:15 Polhemsalen, Room 10134, Uppsala
    Andruszkiewicz, Aneta
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry.
    Quantum Dots for Tandem Solar Cells Applications2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The recent acceleration of climate change has emphasized the urgent need for renewable energy solutions to mitigate the environmental impact of fossil fuel-based energy generation. Solar power stands out for this purpose because of its availability and capacity to meet global energy demands. Colloidal quantum dot (CQD) solar cells, have garnered attention for their unique optoelectronic properties, like tunable bandgaps, solution-processability and the ability to harvest infrared light. This PhD thesis presents a comprehensive investigation of CQD solar cells, and specifically the combination of CQD solar cells with other photovoltaic technologies. The research findings highlight both the potential of CQD-based tandem solar cells and the challenges for the CQD solar cells that must be addressed to enhance the solar to electricity conversion efficiency.

    One focus of the research is the aspects of integrating CQD solar cells with other photovoltaic technologies, such as dye-sensitized and perovskite solar cells. These studies highlight the potential of CQDs to enhance infrared light absorption and energy conversion but reveal critical challenges related to charge recombination and interfacial losses in the CQD solar cell. To address these limitations, the CQD solar cell was investigated in more detail, especially with a focus on surface passivation and the investigation of charge carrier dynamics. Using advanced spectroscopic methods and photoelectrical methods, we could pin-point the most important limitations for the CQD solar cells. The findings demonstrated that effective surface passivation and the optimization of interfacial properties between the CQDs ant the charge extraction layers, are crucial for enhancing charge extraction and minimizing recombination losses in CQD-based solar cells. The results also highlighted the importance of further improve charge transport properties and reduce recombination rates, particularly for larger CQDs.

    These insights show the need for continued research, combining advanced methods, surface ligand development and device engineering, to unlock the full potential of CQD solar cells in tandem applications.

    List of papers
    1. Four-Terminal Tandem Solar Cell with Dye-Sensitized and PbS Colloidal Quantum-Dot-Based Subcells
    Open this publication in new window or tab >>Four-Terminal Tandem Solar Cell with Dye-Sensitized and PbS Colloidal Quantum-Dot-Based Subcells
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    2020 (English)In: ACS Applied Energy Materials, E-ISSN 2574-0962, Vol. 3, no 4, p. 3157-3161Article in journal (Refereed) Published
    Abstract [en]

    In this work, high-performance four-terminal solution-processed tandem solar cells were fabricated by using dye-sensitized solar cells (DSSCs) as top-cells and lead sulfide (PbS) colloidal quantum dot solar cells (CQDSCs) as bottom-cells. For dye-sensitized top-cells, three different dye combinations were used while the titanium dioxide (TiO2) scattering layer was removed to maximize the transmission. For the PbS bottom-cells, quantum dots with different sizes were compared. Over 12% power conversion efficiency has been achieved by using the XL dye mixture and 890 nm PbS QDs, which shows a significant efficiency enhancement when compared to single DSSC or CQDSC subcells.

    Place, publisher, year, edition, pages
    AMER CHEMICAL SOC, 2020
    Keywords
    PbS, quantum dot solar cell, dye-sensitized solar cell, solution-processed, four-terminal tandem
    National Category
    Energy Engineering Materials Chemistry Physical Chemistry
    Identifiers
    urn:nbn:se:uu:diva-412596 (URN)10.1021/acsaem.0c00030 (DOI)000529190300006 ()
    Funder
    Swedish Energy AgencyStiftelsen Olle Engkvist ByggmästareÅForsk (Ångpanneföreningen's Foundation for Research and Development)
    Available from: 2020-06-10 Created: 2020-06-10 Last updated: 2025-02-14Bibliographically approved
    2. Perovskite and quantum dot tandem solar cells with interlayer modification for improved optical semitransparency and stability
    Open this publication in new window or tab >>Perovskite and quantum dot tandem solar cells with interlayer modification for improved optical semitransparency and stability
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    2021 (English)In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 13, no 12, p. 6234-6240Article in journal (Refereed) Published
    Abstract [en]

    In this work, four-terminal (4T) tandem solar cells were fabricated by using a methylammonium lead iodide (MAPbI3) perovskite solar cell (PSC) as the front-cell and a lead sulfide (PbS) colloidal quantum dot solar cell (CQDSC) as the back-cell. Different modifications of the tandem interlayer, at the interface between the sub-cells, were tested in order to improve the infrared transparency of the perovskite sub-cell and consequently increase the utilization of infrared (IR) light by the tandem system. This included the incorporation of a semi-transparent thin gold electrode (Au) on the MAPbI3 solar cell, followed by adding a molybdenum(VI) oxide (MoO3) layer or a surlyn layer. These interlayer modifications resulted in an increase of the IR transmittance to the back cell and improved the optical stability, compared to that in the reference devices. This investigation shows the importance of the interlayer, connecting the PSC with a strong absorption in the visible region and the CQDSC with a strong infrared absorption to obtain efficient next-generation tandem photovoltaics (PVs).

    Place, publisher, year, edition, pages
    Royal Society of Chemistry, 2021
    National Category
    Materials Chemistry
    Identifiers
    urn:nbn:se:uu:diva-453866 (URN)10.1039/d0nr08375e (DOI)000631713700001 ()33885609 (PubMedID)
    Funder
    Swedish Energy AgencyStiftelsen Olle Engkvist ByggmästareÅForsk (Ångpanneföreningen's Foundation for Research and Development)
    Available from: 2021-09-24 Created: 2021-09-24 Last updated: 2025-02-14Bibliographically approved
    3. Combining Quantum Dot and Perovskite Photovoltaic Cells for Efficient Photon to Electricity Conversion in Energy Storage Devices
    Open this publication in new window or tab >>Combining Quantum Dot and Perovskite Photovoltaic Cells for Efficient Photon to Electricity Conversion in Energy Storage Devices
    2022 (English)In: Energy Technology, ISSN 2194-4288, E-ISSN 2194-4296, Vol. 10, no 10, article id 2200598Article in journal (Refereed) Published
    Abstract [en]

    Renewable energy sources, such as wind and solar power, are increasingly important today to reduce emissions from fossil-based energy sources. However, the electricity from wind and solar power varies over time and depends on weather conditions and the time of the day. Therefore, to include a large fraction of electricity from these energy sources in the electricity grid, large-scale and low-cost energy storage is needed. Herein, it is investigated how a combination of quantum dot based photovoltaic cells and perovskite-based photovoltaic cells can be used to increase the energy conversion efficiency and increase the working range of energy storage devices based on conversion between heat, light, and electricity. The results show that these new types of photovoltaic materials have very promising properties for efficient utilization in energy storage devices, which have the potential for large-scale and low-cost energy storage.

    Place, publisher, year, edition, pages
    John Wiley & Sons, 2022
    Keywords
    batteries, energy storage, radiation, TES, thermal losses
    National Category
    Energy Systems Energy Engineering
    Identifiers
    urn:nbn:se:uu:diva-490339 (URN)10.1002/ente.202200598 (DOI)000850308000001 ()
    Available from: 2022-12-08 Created: 2022-12-08 Last updated: 2025-02-14Bibliographically approved
    4. Regulating Thiol Ligands of p-Type Colloidal Quantum Dots for Efficient Infrared Solar Cells
    Open this publication in new window or tab >>Regulating Thiol Ligands of p-Type Colloidal Quantum Dots for Efficient Infrared Solar Cells
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    2021 (English)In: ACS Energy Letters, E-ISSN 2380-8195, Vol. 6, no 5, p. 1970-1989Article in journal (Refereed) Published
    Abstract [en]

    The p-type semiconducting colloidal quantum dot (CQD), working as a hole conductor in CQD solar cells (CQDSCs), is critical for charge carrier extraction and therefore, to large extent, determines the device's photovoltaic performance. However, during the preparation of a p-type CQD solid film on the top of an n-type CQD solid film, forming a p-n heterojunction within the CQDSCs, the optoelectronic properties of the underlayered n-type CQD solid film are significantly affected by conventional 1,2-ethanedithiol (EDT) ligands due to its high reactivity. Herein, a series of thiol ligands are comprehensively studied for p-type CQDs, which suggests that, by finely controlling the interaction between the CQDs and thiol ligands during the preparation of p-type CQD solid films, the n-type CQD solid films can be well protected and avoid destruction induced by thiol ligands. The p-type CQD solid film with 4-aminobenzenethiol (ABT) passivating the CQD surface exhibits better optoelectronic properties than the conventional p-type EDT-based CQD solid films, resulting in an improved photovoltaic performance in CQDSCs.

    Place, publisher, year, edition, pages
    American Chemical Society (ACS), 2021
    National Category
    Materials Chemistry Physical Chemistry
    Identifiers
    urn:nbn:se:uu:diva-446904 (URN)10.1021/acsenergylett.1c00475 (DOI)000651810400033 ()
    Available from: 2021-06-23 Created: 2021-06-23 Last updated: 2025-02-14Bibliographically approved
    5. Interfacial charge transfer dynamics between 2H-MoS2 and PbS quantum dots, the role of quantum confinement
    Open this publication in new window or tab >>Interfacial charge transfer dynamics between 2H-MoS2 and PbS quantum dots, the role of quantum confinement
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Condensed Matter Physics Physical Chemistry
    Identifiers
    urn:nbn:se:uu:diva-550365 (URN)
    Available from: 2025-02-14 Created: 2025-02-14 Last updated: 2025-02-14
    6. A method for studying pico to microsecond time-resolved core-level spectroscopy used to investigate electron dynamics in quantum dots
    Open this publication in new window or tab >>A method for studying pico to microsecond time-resolved core-level spectroscopy used to investigate electron dynamics in quantum dots
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    2020 (English)In: Scientific Reports, E-ISSN 2045-2322, Vol. 10, article id 22438Article in journal (Refereed) Published
    Abstract [en]

    Time-resolved photoelectron spectroscopy can give insights into carrier dynamics and offers the possibility of element and site-specific information through the measurements of core levels. In this paper, we demonstrate that this method can access electrons dynamics in PbS quantum dots over a wide time window spanning from pico- to microseconds in a single experiment carried out at the synchrotron facility BESSY II. The method is sensitive to small changes in core level positions. Fast measurements at low pump fluences are enabled by the use of a pump laser at a lower repetition frequency than the repetition frequency of the X-ray pulses used to probe the core level electrons: Through the use of a time-resolved spectrometer, time-dependent analysis of data from all synchrotron pulses is possible. Furthermore, by picosecond control of the pump laser arrival at the sample relative to the X-ray pulses, a time-resolution limited only by the length of the X-ray pulses is achieved. Using this method, we studied the charge dynamics in thin film samples of PbS quantum dots on n-type MgZnO substrates through time-resolved measurements of the Pb 5d core level. We found a time-resolved core level shift, which we could assign to electron injection and charge accumulation at the MgZnO/PbS quantum dots interface. This assignment was confirmed through the measurement of PbS films with different thicknesses. Our results therefore give insight into the magnitude of the photovoltage generated specifically at the MgZnO/PbS interface and into the timescale of charge transport and electron injection, as well as into the timescale of charge recombination at this interface. It is a unique feature of our method that the timescale of both these processes can be accessed in a single experiment and investigated for a specific interface.

    Place, publisher, year, edition, pages
    NATURE RESEARCH, 2020
    National Category
    Physical Chemistry Atom and Molecular Physics and Optics
    Identifiers
    urn:nbn:se:uu:diva-434199 (URN)10.1038/s41598-020-79792-z (DOI)000605618400009 ()33384445 (PubMedID)
    Available from: 2021-02-08 Created: 2021-02-08 Last updated: 2025-02-14Bibliographically approved
    7. Comparing Charge Generation, Transport and Recombination in PbS Quantum Dot Solar Cells Prepared from Two Sizes of Quantum Dots
    Open this publication in new window or tab >>Comparing Charge Generation, Transport and Recombination in PbS Quantum Dot Solar Cells Prepared from Two Sizes of Quantum Dots
    (English)Manuscript (preprint) (Other academic)
    National Category
    Physical Chemistry
    Identifiers
    urn:nbn:se:uu:diva-545698 (URN)
    Available from: 2024-12-19 Created: 2024-12-19 Last updated: 2025-02-14
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  • Public defence: 2025-04-04 09:15 Lecture hall Sonja Lyttkens, Uppsala
    Hammadi, Souzan
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Mesoscopic and Atomistic Insights into the Microstructural Evolution of Energy Storage Materials2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Energy storage is possible through the incorporation of Li-electron pairs into battery electrodes. Depending on the nature of the interactions between the species within electrode materials, different atomic arrangements can form. Weak interactions result in an even distribution of Li forming a solid solution phase, while strong interactions result in short range order and ultimately in phase separation. A material that undergoes phase separation during battery operation is LiFePO4 and structural mismatch at the Li-rich (LFP) and Li-poor (FP) phase boundaries create strain fields that, over time, lead to mechanical damage. This material showcases both phase separation and solid solution behaviour at different conditions due to its complex short and long range order at the atomic scale. Understanding the factors underlying Li order is, therefore, important to avoid unwanted aging effects and in the design of more efficient electrode materials. This is explored in this thesis using computational modelling at many scales.

    A phase-field model is developed to evaluate the effect of the charge transfer rate on the microstructural evolution at the mesoscale. Two models of charge transfer are confronted, the Butler-Volmer model of ion transfer and the Marcus-Hush-Chidsey model of electron transfer. Depending on the model and the chosen input, different discharge rates and microstructures can be expected. The microstructure evolution also depends on the free energy landscape which generally is approximated with the regular solution model. In contrast, many free energy descriptions parameterized on experimental data showcase an asymmetric form with a third local minima. This minimum represents a metastable solid solution that evolves at room temperature when integrated into the phase-field model.

    Such an asymmetric energy landscape is also to be expected as the short range order of LFP is lower than in FP. This indicates that accessing the solid solution phase is easier during Li extraction.  Addition of dopants such as Mn further decreases the short range order in the material. Finding routes to stabilize the solid solution phase in LFP will ultimately enhance the battery cycling rate and mechanical stability as seen in the phase-field model, where higher rates and lower strains are now possible.  

    List of papers
    1. Investigation of charge transfer models on the evolution of phases in lithium iron phosphate batteries using phase-field simulations
    Open this publication in new window or tab >>Investigation of charge transfer models on the evolution of phases in lithium iron phosphate batteries using phase-field simulations
    2025 (English)In: Journal of Materials Chemistry A, ISSN 2050-7488, E-ISSN 2050-7496, Vol. 13, no 4, p. 2849-2858Article in journal (Refereed) Published
    Abstract [en]

    Charge transfer is essential for all electrochemical processes, such as in batteries where it is facilitated through the incorporation of ion–electron pairs into solid crystals. The low solubility of lithium (Li) in some of these host lattices cause phase changes, which for example happens in FePO4. This results in the growth of interfacial patterns at the mesoscale between a Li-poor and Li-rich phase, FePO4 and LiFePO4 respectively. Conventionally, the effect of charge transfer on the evolution of these phases is usually modelled using the Butler–Volmer equation. However, the exponentially increasing current–overpotential relation in this formalism becomes problematic for battery systems operating under high currents. In this study, we implement a phase-field model to investigate two electrochemical reaction models: the Butler–Volmer and the Marcus–Hush–Chidsey formulation. We assess their effect on the spatial and temporal evolution of the FePO4 and LiFePO4 phases. Both reaction models demonstrate similar microstructural patterns in equilibrium. Nevertheless, a significant increase in current density is caused by using the Butler–Volmer expression, leading to an accelerated reaction rate at high overpotentials and an exaggerated delithiation. Furthermore, we show that including anisotropic elastic strain fields in the phase-field model accelerates the delithiation process, reaching the bulk mass transport limitation faster. These elastic effects, when included in the overpotential, can cause the current density to exceed its limits, a problem inherently mitigated by the Marcus–Hush–Chidsey model.

    Place, publisher, year, edition, pages
    Royal Society of Chemistry, 2025
    National Category
    Materials Chemistry
    Identifiers
    urn:nbn:se:uu:diva-550347 (URN)10.1039/d4ta06444e (DOI)001379530900001 ()2-s2.0-85212701923 (Scopus ID)
    Funder
    eSSENCE - An eScience CollaborationStandUpNational Academic Infrastructure for Supercomputing in Sweden (NAISS)National Supercomputer Centre (NSC), Sweden
    Available from: 2025-02-13 Created: 2025-02-13 Last updated: 2025-02-17Bibliographically approved
    2. Consecutive intra-particle phase transitions in LiFePO4 battery electrodes
    Open this publication in new window or tab >>Consecutive intra-particle phase transitions in LiFePO4 battery electrodes
    (English)Manuscript (preprint) (Other academic)
    National Category
    Materials Chemistry
    Identifiers
    urn:nbn:se:uu:diva-550469 (URN)
    Available from: 2025-02-16 Created: 2025-02-16 Last updated: 2025-02-16
    3. Impact of temperature on short-range charge ordering in LiFePO4/FePO4
    Open this publication in new window or tab >>Impact of temperature on short-range charge ordering in LiFePO4/FePO4
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    2024 (English)In: Physical Review B, ISSN 2469-9950, E-ISSN 2469-9969, Vol. 109, no 14, article id 144103Article in journal (Refereed) Published
    Abstract [en]

    Energy is stored in a LiFePO4 battery electrode through the intercalation of Li. As Li incorporate into the crystal lattice of Fe⁡(III)⁢PO4, electrons reduce Fe(III) into Fe(II). The interactions of Li and its vacant site (Va) with these localized electrons (holes), so-called polarons, cause phase separation during battery operation. These fundamental interactions are however difficult to quantify using standard electronic structure calculations. In this paper, we utilize DFT+𝑈 with occupation matrix control to compute interaction energies at varying Li-Fe(II) and Va-Fe(III) pair separations. The increased energy with separation warrants the use of an electrostatic description. The DFT+𝑈 data are fitted to a Coulombic potential with two-body corrections and used in a Monte Carlo scheme. The coordination of the species determines their short-range ordering, showing that the Li and Va create chains bridged by their associated polarons which dissociate into dimers at higher temperatures. This dissociation happens at higher temperatures for Va than for Li, indicating a more pronounced clustering behavior during the formation of FePO4. Notably, a significant amount of uncoordinated Li exists at elevated temperatures, challenging the simplified picture of complete Li-Fe(II) pairing.

    Place, publisher, year, edition, pages
    American Physical Society, 2024
    National Category
    Condensed Matter Physics Physical Chemistry Theoretical Chemistry
    Identifiers
    urn:nbn:se:uu:diva-530449 (URN)10.1103/PhysRevB.109.144103 (DOI)001229771600002 ()
    Funder
    EU, Horizon 2020, 957189StandUpSwedish Research Council, 2022-06725eSSENCE - An eScience CollaborationNational Academic Infrastructure for Supercomputing in Sweden (NAISS)
    Available from: 2024-06-05 Created: 2024-06-05 Last updated: 2025-02-16Bibliographically approved
    4. Cluster analysis of Mn-doped LiFePO4
    Open this publication in new window or tab >>Cluster analysis of Mn-doped LiFePO4
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Materials Chemistry
    Identifiers
    urn:nbn:se:uu:diva-550468 (URN)
    Available from: 2025-02-16 Created: 2025-02-16 Last updated: 2025-02-16
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    UUThesis_S-Hammadi-2025
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  • Public defence: 2025-04-04 09:15 A1:111a, Uppsala
    Saporta, Raphaël
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Model-based translation of antibiotic-bacteria-neutrophil interactions2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The rapid emergence of antibiotic resistance warrants the development of new antibiotics and the optimisation of the use of existing ones. Novel translational methods could help maximise the information gained from preclinical data generated during drug development. Despite the pivotal role of the host’s immune system in infection control, interactions between antibiotics, bacteria and the immune system are not fully understood. Pharmacokinetic-pharmacodynamic (PKPD) modelling approaches, which allow to describe changes in bacterial load over time, were used in this thesis to evaluate model-based translation for antibiotics and characterise the impact of immune response on bacterial killing and antibiotic PKPD.

    PKPD models were built for meropenem and afabicin to describe bacterial dynamics in vitro using static time-kill data, and in vivo using mouse thigh or lung infection data. Neutropenic and immunocompetent mouse infection models were used to investigate the contribution of immune response. Translation of antibiotic effects was explored by standard PK/PD index-based approaches and by using the developed PKPD models to perform predictions of bacterial dynamics in different systems. The impact of the design of mouse dose fractionation studies on antibiotic PKPD analyses was also assessed in a simulation-based analysis.

    Through model-based analyses, the PKPD relationships for the effects of meropenem and afabicin on bacterial killing, with and without an intact immune system, were quantitatively characterised. An in vivo effect of meropenem against resistant Escherichia coli and Klebsiella pneumoniae was identified. By studying mice with varying degrees of immunosuppression, differences in meropenem PK and a reduced bacterial killing attributable to meropenem in presence of an immune system were described. A model-based translation framework was successfully developed for afabicin, integrating in vitro data and both neutropenic and immunocompetent mouse thigh infection data. The framework demonstrated the ability to translate the activity of afabicin against Staphylococcus aureus from in vitro to in vivo settings and across bacterial strains, and ultimately predicted bacterial killing in patients. In conclusion, the studies performed in this thesis contributed to advancements in the development and application of model-based translation approaches for antibiotics and enhanced the understanding of interactions between antibiotics, bacteria and the immune system.

    List of papers
    1. PK/PD modelling and simulation of longitudinal meropenem in vivo effects against Escherichia coli and Klebsiella pneumoniae strains with high MICs
    Open this publication in new window or tab >>PK/PD modelling and simulation of longitudinal meropenem in vivo effects against Escherichia coli and Klebsiella pneumoniae strains with high MICs
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    2024 (English)In: International Journal of Antimicrobial Agents, ISSN 0924-8579, E-ISSN 1872-7913, Vol. 64, no 6, article id 107389Article in journal (Refereed) Published
    Abstract [en]

    Background: Carbapenem-resistant bacteria pose a threat to public health. Characterising thepharmacokinetics-pharmacodynamics (PKPD) of meropenem longitudinally in vivo against resistant bacteria could provide valuable information for development and translation of carbapenem-based therapies.

    Objectives: To assess the time course of meropenem effects in vivo against strains with high MIC topredict PK/PD indices and expected efficacy in patients using a modelling approach.

    Methods: A PKPD model was built on longitudinal bacterial count data to describe meropenem effectsagainst six Escherichia coli and Klebsiella pneumoniae strains (MIC values 32–128 mg/L) in a 24 h mousethigh infection model. The model was used to derive PK/PD indices from simulated studies in mice andto predict the efficacy of different infusion durations with high-dose meropenem (2 g q8 h/q12 h fornormal/reduced kidney function) in patients.

    Results: Data from 592 mice were available for model development. The estimated meropenemconcentration-dependent killing rate was not associated with differences in MIC. The fraction of timethat unbound concentrations exceeded EC50 (fT>EC50, EC50 = 1.01 mg/L) showed higher correlations thanfT>MIC. For all investigated strains, bacteriostasis at 24 h was predicted for prolonged infusions of highdose meropenem monotherapy in >90% of patients.

    Conclusions: The developed PKPD model successfully described bacterial growth and meropenem killingover time in the thigh infection model. For the investigated strains, the MIC, determined in vitro, orMIC-based PK/PD indices, did not predict in vivo response. Simulations suggested prolonged infusions ofhigh-dose meropenem to be efficacious in patients infected by the studied strains

    Place, publisher, year, edition, pages
    Elsevier, 2024
    Keywords
    PKPD, Meropenem, Carbapenem resistance, Pharmacometrics, Mouse thigh infection model
    National Category
    Pharmaceutical Sciences
    Identifiers
    urn:nbn:se:uu:diva-545154 (URN)10.1016/j.ijantimicag.2024.107389 (DOI)001374407900001 ()39551277 (PubMedID)2-s2.0-85210683034 (Scopus ID)
    Funder
    EU, Horizon 2020, 861323Swedish Research Council, 2022-00657
    Available from: 2024-12-12 Created: 2024-12-12 Last updated: 2025-02-18Bibliographically approved
    2. Simulation-based evaluation of the impact of dose fractionation study design on antibiotic PKPD analyses
    Open this publication in new window or tab >>Simulation-based evaluation of the impact of dose fractionation study design on antibiotic PKPD analyses
    (English)Manuscript (preprint) (Other academic)
    National Category
    Pharmaceutical Sciences
    Identifiers
    urn:nbn:se:uu:diva-549465 (URN)
    Available from: 2025-02-04 Created: 2025-02-04 Last updated: 2025-02-12
    3. Pharmacokinetic-pharmacodynamic modelling to evaluate the relative impact of immune response and meropenem on bacterial killing in vivo
    Open this publication in new window or tab >>Pharmacokinetic-pharmacodynamic modelling to evaluate the relative impact of immune response and meropenem on bacterial killing in vivo
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Pharmaceutical Sciences
    Identifiers
    urn:nbn:se:uu:diva-549486 (URN)
    Available from: 2025-02-04 Created: 2025-02-04 Last updated: 2025-02-12
    4. Model-based translation of results from in vitro to in vivo experiments for afabicin activity against Staphylococcus aureus
    Open this publication in new window or tab >>Model-based translation of results from in vitro to in vivo experiments for afabicin activity against Staphylococcus aureus
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    2024 (English)In: Journal of Antimicrobial Chemotherapy, ISSN 0305-7453, E-ISSN 1460-2091, Vol. 79, no 12, p. 3150-3159Article in journal (Refereed) Published
    Abstract [en]

    Background: Translation of experimental data on antibiotic activity typically relies on pharmacokinetic/pharmacodynamic (PK/PD) indices. Model-based approaches, considering the full antibiotic killing time course, could be an alternative.

    Objectives: To develop a mechanism-based modelling framework to assess the in vitro and in vivo activity of the FabI inhibitor antibiotic afabicin, and explore the ability of a model built on in vitro data to predict in vivo outcome.

    Methods: A PK/PD model was built to describe bacterial counts from 162 static in vitro time-kill curves evaluating the effect of afabicin desphosphono, the active moiety of the prodrug afabicin, against 21 Staphylococcus aureus strains. Combined with a mouse PK model, outcomes of afabicin doses of 0.011-190 mg/kg q6h against nine S. aureus strains in a murine thigh infection model were predicted, and thereafter refined by estimating PD parameters.

    Results: A sigmoid Emax model, with EC50 scaled by the MIC described the afabicin desphosphono killing in vitro. This model predicted, without parameter re-estimation, the in vivo bacterial counts at 24 h within a ±1 log margin for most dosing groups. When parameters were allowed to be estimated, EC50 was 38%-45% lower in vivo, compared with in vitro, within the studied MIC range.

    Conclusions: The developed PK/PD model described the time course of afabicin activity across experimental conditions and bacterial strains. This model showed translational capacity as parameters estimated on in vitro time-kill data could well predict the in vivo outcome for a wide variety of doses in a mouse thigh infection model.

    Place, publisher, year, edition, pages
    Oxford University Press, 2024
    National Category
    Pharmaceutical Sciences
    Identifiers
    urn:nbn:se:uu:diva-545159 (URN)10.1093/jac/dkae334 (DOI)001320118100001 ()39315768 (PubMedID)
    Funder
    EU, Horizon 2020, 861323
    Available from: 2024-12-12 Created: 2024-12-12 Last updated: 2025-02-12Bibliographically approved
    5. Impact of immune response on afabicin activity in an immunocompetent mouse thigh infection model quantified with a model-based approach
    Open this publication in new window or tab >>Impact of immune response on afabicin activity in an immunocompetent mouse thigh infection model quantified with a model-based approach
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Pharmaceutical Sciences
    Identifiers
    urn:nbn:se:uu:diva-549487 (URN)
    Available from: 2025-02-04 Created: 2025-02-04 Last updated: 2025-02-12
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  • Public defence: 2025-04-04 10:00 Brömssalen, Gävle
    Bandert, Anna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Anaesthesiology and Intensive Care. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Disciplinary Domain of Medicine and Pharmacy, research centers etc., Centre for Research and Development, Gävleborg. Centrum för Forskning och Utveckling Gävleborg.
    The phenomenon of direct aspiration and its possible clinical applications2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background: Critically ill patients in intensive care units (ICUs) often require organ support, including mechanical ventilation, vasopressors, and dialysis. Central venous catheters (CVCs) are commonly used for drug administration, while central dialysis catheters (CDKs) enable continuous renal replacement therapy (CRRT). This thesis investigated the potential phenomenon of direct aspiration of a drug infused in a CVC into the CDK during CRRT, leading to unintended clearance, and explored its clinical implications and also physicians’ catheter insertion practices. To achieve this, experimental animal models and a cross-sectional survey study were employed.

    Methods and Results:

    Study I examined the impact of catheter placement on drug concentration and vasopressor requirements. Results showed lower antibiotic concentrations and a twofold increase in noradrenaline demand, during CRRT, when CVC and CDK were placed in the same vessel compared to separate vessels.

    Study II assessed antibiotic clearance under endotoxaemic conditions, demonstrating higher clearance in CRRT when both catheters were in the same vessel.

    Study III explored how different CVC-CDK tip distances influenced clearance, during CRRT. The lowest clearance was observed when catheter tips were parallel or when the CVC tip was closer to the heart than the CDK.

    Study IV investigated European ICU physicians’ catheter placement preferences. The right internal jugular vein was the preferred site for both CVC and CDK. Ultrasound was frequently used for insertion but less often for tip position confirmation. Notably, 70% of respondents expressed concerns regarding catheter tip positioning in the same vessel, and 30% had suspected drug aspiration from a CVC into a CDK during their clinical careers.

    Conclusion: Direct aspiration of drugs from a CVC into a CDK can occur during CRRT, potentially affecting drug clearance. 

    European physicians prefer the right internal jugular vein for placement regarding both catheters, with ultrasound frequently used for insertion but less often for tip confirmation.

    List of papers
    1. Central Venous Line and Dialysis Catheter Position Affects Drug Clearance during Continuous Renal Replacement Therapy in an Animal Model.
    Open this publication in new window or tab >>Central Venous Line and Dialysis Catheter Position Affects Drug Clearance during Continuous Renal Replacement Therapy in an Animal Model.
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    2019 (English)In: ASAIO journal (1992), ISSN 1058-2916, E-ISSN 1538-943X, Vol. 65, no 4, p. 408-413Article in journal (Refereed) Published
    Abstract [en]

    In intensive care, drugs are commonly administered through central venous catheters (CVC). These catheters and central venous dialysis catheters (CVDC) are often placed in the same vessel for practical reasons. The aim of this experimental study was to investigate if the position of CVC and CVDC influences the elimination of infused drugs, during continuous renal replacement therapy (CRRT). In a randomized, cross-over model, anesthetized piglets received both a CVC and a CVDC in a jugular vein. Another CVDC was placed in a femoral vein for comparison. After baseline measurements, CRRT was performed in either of the CVDC, each CRRT-period separated by another baseline period. Hypotension was induced by peripherally given sodium nitroprusside. In the CVC, both gentamicin and noradrenaline were administered. Noradrenaline was titrated to reach a target blood pressure. When CRRT was performed using the CVDC in the same vessel as the drugs were infused, the plasma concentration of gentamicin was reduced compared with when the infusion and CVDC were in different vessels (5.66 [standard deviation (SD) ± 1.23] vs. 7.76 [SD ± 2.30] mg/L [p = 0.02]). The noradrenaline infusion rate needed to reach the target blood pressure was more than doubled (0.32 [SD ± 0.16] vs. 0.15 [SD ± 0.08] µg/kg/min [p = 0.006]). This experimental study indicates that the removal of drugs is increased if infusion is in close vicinity of the CVDC, during CRRT.

    National Category
    Anesthesiology and Intensive Care
    Identifiers
    urn:nbn:se:uu:diva-353342 (URN)10.1097/MAT.0000000000000839 (DOI)000466791000022 ()29863633 (PubMedID)
    Funder
    Swedish Research Council, 523-2014-2569
    Available from: 2018-10-18 Created: 2018-10-18 Last updated: 2025-02-15Bibliographically approved
    2. Different distances between central venous catheter tips can affect antibiotic clearance during continuous renal replacement therapy
    Open this publication in new window or tab >>Different distances between central venous catheter tips can affect antibiotic clearance during continuous renal replacement therapy
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    2024 (English)In: Intensive Care Medicine Experimental, E-ISSN 2197-425X, Vol. 12, no 1, article id 56Article in journal (Refereed) Published
    Abstract [en]

    BACKGROUND: The aim of this experimental study was to elucidate whether different distances between central venous catheter tips can affect drug clearance during continuous renal replacement therapy (CRRT). Central venous catheters (CVCs) are widely used in intensive care patients for drug infusion. If a patient receives CRRT, a second central dialysis catheter (CDC) is required. Where to insert CVCs is directed by guidelines, but recommendations regarding how to place multiple catheters are scarce. There are indications that a drug infused in a CVC with the tip close to the tip of the CDC, could be directly aspirated into the dialysis machine, with a risk of increased clearance. However, studies on whether clearance is affected by different CVC and CDC tip positions, when the two catheters are in the same vessel, are few.

    METHODS: In this model with 18 piglets, gentamicin (GM) and vancomycin (VM) were infused through a CVC during CRRT. The CVC tip was placed in different positions in relation to the CDC tip from caudal, i.e., proximal to the heart, to cranial, i.e., distal to the heart. Serum and dialysate concentrations were sampled after approximately 30 min of CRRT at four different positions: when the CVC tip was 2 cm caudally (+ 2), at the same level (0), and at 2 (- 2) and 4 (- 4) cm cranially of the tip of the CDC. Clearance was calculated. A mixed linear model was performed, and level of significance was set to p < 0.05.

    RESULTS: Clearance of GM had median values at + 2 cm, 0 cm, - 2 cm and - 4 cm of 17.3 (5.2), 18.6 (7.4), 20.0 (16.2) and 26.2 (12.2) ml/min, respectively (p = 0.04). Clearance of VM had median values at + 2 cm, 0 cm, - 2 cm and - 4 cm of 16.2 (4.5), 14.7 (4.9), 19.0 (10.2) and 21.2 (11.4) ml/min, respectively (p = 0.02).

    CONCLUSIONS: The distance between CVC and CDC tips can affect drug clearance during CRRT. A cranial versus a caudal tip position of the CVC in relation to the tip of the CDC led to the highest clearance.

    Place, publisher, year, edition, pages
    Springer Nature, 2024
    Keywords
    Acute kidney injury, Antibiotic concentration, Central venous catheter, Clearance, Continuous renal replacement therapy, Dialysis, Intensive care, Renal replacement therapy
    National Category
    Anesthesiology and Intensive Care
    Identifiers
    urn:nbn:se:uu:diva-533429 (URN)10.1186/s40635-024-00635-6 (DOI)001253360000001 ()38913212 (PubMedID)
    Available from: 2024-06-26 Created: 2024-06-26 Last updated: 2025-02-15Bibliographically approved
    3. In an endotoxaemic model, antibiotic clearance can be affected by different central venous catheter positions, during renal replacement therapy
    Open this publication in new window or tab >>In an endotoxaemic model, antibiotic clearance can be affected by different central venous catheter positions, during renal replacement therapy
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    2023 (English)In: Intensive Care Medicine Experimental, E-ISSN 2197-425X, Vol. 11, no 1, article id 32Article in journal (Refereed) Published
    Abstract [en]

    BACKGROUND: In intensive care, different central venous catheters (CVC) are often used for infusion of drugs. If a patient is treated with continuous renal replacement therapy (CRRT) a second catheter, a central venous dialysis catheter (CVDC), is needed. Placing the catheters close together might pose a risk that a drug infused in a CVC could be directly aspirated into a CRRT machine and cleared from the blood without giving the effect intended. The purpose of this study was to elucidate if drug clearance is affected by different catheter placement, during CRRT. In this endotoxaemic animal model, an infusion of antibiotics was administered in a CVC placed in the external jugular vein (EJV). Antibiotic clearance was compared, whether CRRT was through a CVDC placed in the same EJV, or in a femoral vein (FV). To reach a target mean arterial pressure (MAP), noradrenaline was infused through the CVC and the dose was compared between the CDVDs.

    RESULTS: The main finding in this study was that clearance of antibiotics was higher when both catheter tips were in the EJV, close together, compared to in different vessels, during CRRT. The clearance of gentamicin was 21.0 ± 7.3 vs 15.5 ± 4.2 mL/min (p 0.006) and vancomycin 19.3 ± 4.9 vs 15.8 ± 7.1 mL/min (p 0.021). The noradrenaline dose to maintain a target MAP also showed greater variance with both catheters in the EJV, compared to when catheters were placed in different vessels.

    CONCLUSION: The results in this study indicate that close placement of central venous catheter tips could lead to unreliable drug concentration, due to direct aspiration, during CRRT.

    Place, publisher, year, edition, pages
    Springer Nature, 2023
    Keywords
    Acute kidney injury, Central venous catheter, Continuous renal replacement therapy antibiotic concentration, Dialysis, Intensive care, Sepsis
    National Category
    Anesthesiology and Intensive Care Clinical Medicine
    Identifiers
    urn:nbn:se:uu:diva-504226 (URN)10.1186/s40635-023-00516-4 (DOI)001002679600001 ()37291474 (PubMedID)
    Funder
    Uppsala University
    Available from: 2023-06-12 Created: 2023-06-12 Last updated: 2025-02-18Bibliographically approved
    4. Central venous catheters, the anaesthetist´s and intensivist´s choice of insertion site and use of ultrasound. An international Survey
    Open this publication in new window or tab >>Central venous catheters, the anaesthetist´s and intensivist´s choice of insertion site and use of ultrasound. An international Survey
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    (English)Manuscript (preprint) (Other academic)
    Keywords
    central lines, central venous catheters, intensive care, critical care, ultrasound, online survey, ESICM
    National Category
    Anesthesiology and Intensive Care
    Research subject
    Medical Science
    Identifiers
    urn:nbn:se:uu:diva-549833 (URN)
    Available from: 2025-02-09 Created: 2025-02-09 Last updated: 2025-02-15
    5. Central venous catheters, the anaesthetist´s and intensivist´s choice of insertion site and use of ultrasound. An international Survey
    Open this publication in new window or tab >>Central venous catheters, the anaesthetist´s and intensivist´s choice of insertion site and use of ultrasound. An international Survey
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Keywords
    central lines, central venous catheters, intensive care, critical care, ultrasound, online survey, ESICM
    National Category
    Anesthesiology and Intensive Care
    Research subject
    Medical Science
    Identifiers
    urn:nbn:se:uu:diva-549833 (URN)
    Available from: 2025-02-09 Created: 2025-02-09 Last updated: 2025-02-15
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  • Public defence: 2025-04-04 13:15 Humanistiska teatern, Uppsala
    Hellström, Emma
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Educational Sciences, Department of Education. Department of Education, Uppsala University.
    Kampen om folkhemskristendomen: Kristendomsundervisningens roll i den demokratiska skolans framväxt, 1920–19692025Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis investigates the role of Christian education in the emergence of democratic schools in Sweden from 1920 to 1969. Following the introduction of the curriculum of 1919, the previous one-sided focus on Evangelical-Lutheran Christianity was weakened in favor of a broader Christian message based on the Bible, particularly the ethical teachings found in the Sermon on the Mount. 

    For a long time, previous educational research has taken these changes as evidence that Swedish primary schools became secularized and that Christianity lost its relevance in fostering desirable citizens. In contrast to previous research, I argue that Christian education, though redefined, continued to be a significant national, cultural, and ethical pillar within education throughout the 20th century. The aim of the thesis is to expand and deepen our understanding of the role of Christian education in primary schools from 1920 to 1969. 

    Inspired by a Gramscian concept of hegemony, the thesis explains how competing ideas of the purpose and content of Christian education could coexist, and how their legitimacy shifted over time. Drawing on parliamentary debates, teachers’ magazines, records from the State Textbook Board, minutes from Synod meetings, minutes from Free Church meetings, national curricula, local syllabi, and textbooks, the analysis charts the transformation of Christian education through three chronological phases. 

    The analysis shows a transition from an ecclesiastical Christianity to a national Christianity of the people’s home (folkhemskristendom). This form of Christianity resolved previous elements of conflict and positioned itself between Lutheran confession and secularity, giving Christian education a more immanent and ethical focus. 

    This folkhemskristendom was constantly negotiated during the period of investigation. The outcome was not necessarily increased secularization; rather it involved adaptation, which allowed Christian education to remain relevant by aligning with the changing social, political, and cultural landscape. Hence, it is inaccurate to assert that there was a clear break between a religious society and the secular welfare state in the 20th century. Instead, I show how the folkhemskristendom served as a bridge between these two extremes. In doing so, this thesis contributes to the ongoing discussion on the revitalization of religion in modern societies, and highlights the adaptability of religious ideas even in increasingly secular societies. 

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  • Public defence: 2025-04-08 09:15 Sonja Lyttkens Å101121, Uppsala
    Shi, Qian
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Microsystems Technology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Acoustic manipulation in two-phase systems2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Droplet-microfluidic platforms enable precise processing, manipulation, and analysis of biological samples with improved throughput, cost-efficiency and reduced response times compared to conventional bulk methods. At the microscale, shifts in the relative significance of physical parameters lead to distinct emergent properties, facilitating the creation of physiologically relevant microenvironments with spatiotemporal control over chemical (e.g., growth factors) and mechanical (e.g., hydrogel scaffolds) cues. These capabilities make droplet-microfluidic systems highly suitable for biology and biomedical research, and for applications such as disease diagnostics, cell therapeutics, and regenerative medicine. A fundamental requirement for such platforms is the ability to manipulate the spatial positioning and movement of biological entities for sample enrichment, separation, localization, and patterning. Acoustic forces offer a label-free and non-invasive approach to achieve this control, making them particularly attractive in microfluidic-based devices. This thesis focuses on studying the manipulation of microparticles and cells within droplets and microgels using bulk acoustic wave, aiming to develop on-chip processes that could ultimately be integrated into various cell-related research and applications. In droplet microfluidics, understanding the effects of different fluidic environments on the acoustic manipulation of intra-droplet particles is essential, particularly given the presence of two immiscible phases. Due to biocompatibility constraints, the selection of solutions for the droplet phase is limited. Therefore, the surrounding oil phase was modified in Paper I. Results of Paper I reveal that acoustic field uniformity and strength within the droplet are optimized when the speed of sound of the aqueous droplet and the surrounding oil are closely matched. It was concluded that hydrocarbon oils are more compatible with intra-droplet acoustic focusing, as their acoustic properties more closely approximate those of water. In contrast, fluorinated oils, conventionally favored in droplet microfluidics, were found to be less suitable due to greater disparities in their acoustic properties relative to water. In a subsequent study, the environmental risks associated with fluorinated oils, classified as per- and polyfluoroalkyl substances (PFAS), were assessed. The findings indicate that viable oil/surfactant alternatives to conventional fluorinated solutions exist for specific droplet microfluidic applications, such as the mineral oil/PGPR system for bacterial culture. In Paper III, it was demonstrated that intra-droplet acoustic focusing remains effective when the droplet phase consists of more viscous hydrogel formulations. Precise spatial control of bioparticles within continuously generated hydrogel droplets was successfully achieved, followed by on-chip crosslinking to immobilize particle positions without significantly compromising cell viability. Finally, the acoustic assembly of three-dimensional polystyrene bead clusters within hydrogel matrices was demonstrated, serving as a proof-of-concept for point focusing in microgel constructs via ultrasonic techniques.

    List of papers
    1. Effects of the choice of the continuous phase in droplet microfluidics on internal particle manipulation with acoustophoresis
    Open this publication in new window or tab >>Effects of the choice of the continuous phase in droplet microfluidics on internal particle manipulation with acoustophoresis
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    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    In this work, we have studied how the choice of the continuous phase oils affects droplet-internal acoustic manipulation and mapped the acoustic properties of the selected oils to evaluate their compatibility with droplet acoustofluidic methods. The selection of continuous phase included hydrocarbon, fluorinated and silicone oils. To map the oils’ acoustic properties, we measured their speed of sound and density. We then studied the acoustic performance of each oil for droplet-internal manipulation through experiments and finite-element simulations (COMSOL Multiphysics®).From our results, we conclude that a match between the speed of sound of the continuous and dispersed phases is strongly correlated to the generation of a strong and uniform acoustic field inside the droplet. We demonstrate that conventionally-favoured fluorinated oils in droplet microfluidics are no longer the best choice when also considering droplet-internal acoustic focusing. Instead, hydrocarbon oils, especially linseed oil, are most suitable for this specific application as they generate stable and monodisperse droplets and bear the most resemblance to water in terms of acoustic properties. We believe this collection of data will serve the acoustofluidics community by providing results that aid in the selection of continuous phase in future droplet acoustofluidic studies and data for performing acoustofluidic simulations.

    Keywords
    Acoustofluidics, Ultrasound, Acoustophoresis, Acoustic modeling, Acoustic radiation force, Droplet microfluidics, Microfluidic devices, Particle manipulation, Finite-element analysis.
    National Category
    Engineering and Technology
    Research subject
    Engineering Science with specialization in Biomedical Engineering
    Identifiers
    urn:nbn:se:uu:diva-544390 (URN)
    Funder
    EU, European Research Council, 101043985
    Available from: 2024-12-04 Created: 2024-12-04 Last updated: 2025-02-16
    2. Environment-friendly oils and surfactants for droplet microfluidics – the need to find replacements for PFAS-based chemicals
    Open this publication in new window or tab >>Environment-friendly oils and surfactants for droplet microfluidics – the need to find replacements for PFAS-based chemicals
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    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Droplet microfluidics has emerged as a powerful tool for miniaturizing biological assays. The continuous phase in droplet microfluidics often consists of fluorinated oils and fluorosurfactants. However, these fluids belong to a group of chemicals called PFASs (per-and polyfluoroalkyl substances), which are hazardous for the environment as they are not broken down but remain in the surrounding for a long time. As a result, PFAS chemicals are likely to be unavailable on the market in the near future. Consequently, there is a need to find replacements for fluorinated oils and fluorosurfactants that work well for droplet microfluidics. With this article, we aim to bring awareness to the issue and begin by reviewing the problem with using fluorinated chemicals in droplet microfluidics. Next, we compare the performance of four different oil/surfactant systems: two containing fluorinated oil and two without, to present alternatives for the droplet microfluidics community. Our results show that suitable alternative oil/surfactant systems exist that can effectively replace the conventional fluorinated solutions in droplet microfluidics.

    Keywords
    Droplet microfluidics, PFAS, surfactants
    National Category
    Engineering and Technology
    Research subject
    Engineering Science with specialization in Biomedical Engineering
    Identifiers
    urn:nbn:se:uu:diva-544404 (URN)
    Funder
    EU, European Research Council, 101043985
    Available from: 2024-12-04 Created: 2024-12-04 Last updated: 2025-02-16
    3. Acoustic focusing of beads and cells in hydrogel droplets
    Open this publication in new window or tab >>Acoustic focusing of beads and cells in hydrogel droplets
    2021 (English)In: Scientific Reports, E-ISSN 2045-2322, Vol. 11, no 1, article id 7479Article in journal (Refereed) Published
    Abstract [en]

    The generation of hydrogel droplets using droplet microfluidics has emerged as a powerful tool with many applications in biology and medicine. Here, a microfluidic system to control the position of particles (beads or astrocyte cells) in hydrogel droplets using bulk acoustic standing waves is presented. The chip consisted of a droplet generator and a 380 µm wide acoustic focusing channel. Droplets comprising hydrogel precursor solution (polyethylene glycol tetraacrylate or a combination of polyethylene glycol tetraacrylate and gelatine methacrylate), photoinitiator and particles were generated. The droplets passed along the acoustic focusing channel where a half wavelength acoustic standing wave field was generated, and the particles were focused to the centre line of the droplets (i.e. the pressure nodal line) by the acoustic force. The droplets were cross-linked by exposure to UV-light, freezing the particles in their positions. With the acoustics applied, 89 ± 19% of the particles (polystyrene beads, 10 µm diameter) were positioned in an area ± 10% from the centre line. As proof-of-principle for biological particles, astrocytes were focused in hydrogel droplets using the same principle. The viability of the astrocytes after 7 days in culture was 72 ± 22% when exposed to the acoustic focusing compared with 70 ± 19% for samples not exposed to the acoustic focusing. This technology provides a platform to control the spatial position of bioparticles in hydrogel droplets, and opens up for the generation of more complex biological hydrogel structures.

    Place, publisher, year, edition, pages
    Springer Nature, 2021
    National Category
    Fluid Mechanics
    Research subject
    Engineering Science with specialization in Microsystems Technology
    Identifiers
    urn:nbn:se:uu:diva-441826 (URN)10.1038/s41598-021-86985-7 (DOI)000637816800004 ()33820916 (PubMedID)
    Funder
    EU, European Research Council, ERC-2017-STG-757444Knut and Alice Wallenberg Foundation, WAF 2016.0112Swedish Research Council, 2019-03797
    Note

    These authors contributed equally: Anna Fornell and Hannah Pohlit

    Available from: 2021-05-05 Created: 2021-05-05 Last updated: 2025-02-16Bibliographically approved
    4. Three-dimensional acoustic focusing of particles in microgel blocks
    Open this publication in new window or tab >>Three-dimensional acoustic focusing of particles in microgel blocks
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    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Hydrogels are widely used for cell encapsulation and culture due to their ability to mimic extracellular matrix. Cell-laden hydrogels in the micrometer scale — microgels — offer advantages for single-cell analysis and scaffold-based 3D cell culture. However, challenges such as off-center encapsulation and asymmetric biochemical exposure lead to cellular escape and heterogeneity in cell assemblies, which compromise long-term culture and affects experimental reproducibility. Addressing these limitations requires precise three-dimensional (3D) spatial control of cells within microgels. This study presents 3D acoustic focusing of polystyrene microbeads within gelatin methacyraloyl (GelMA) hydrogel, achieved in a microwell-based acoustofluidic system that employs dual piezoelectric transducers to generate half-wavelength resonances across all three dimensions of cuboid-shaped microwells. Our findings demonstrate a versatile approach for active 3D centering of cells and microparticles in microgels, demonstrating the potential of bulk acoustic wave technologies as a biofabrication technique for biomedical research and regenerative medicine.

    Keywords
    Ultrasound; Acoustophoresis; Acoustofluidics; Microfluidic devices; Particle manipulation; Microgel
    National Category
    Engineering and Technology
    Research subject
    Engineering Science with specialization in Biomedical Engineering
    Identifiers
    urn:nbn:se:uu:diva-544444 (URN)
    Funder
    EU, European Research Council, 101043985
    Available from: 2024-12-04 Created: 2024-12-04 Last updated: 2025-02-16
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  • Public defence: 2025-04-10 09:00 H:son Holmdalsalen, Uppsala
    Pantiora, Eirini
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Endocrine Surgery.
    Magnetic Techniques in Breast Cancer Surgery2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Preoperative tumor localization and axillary mapping in breast cancer surgery are integral for successful breast conserving surgery and axillary staging. They can be performed with a variety of markers and tracers, including magnetic seeds and a liquid sentinel node tracer containing superparamagnetic iron oxide (SPIO) nanoparticles. Although numerous studies have demonstrated the safety and efficacy of both magnetic seeds and SPIO in breast cancer surgery, further research is needed to optimize their application and maximize their potential benefits.

    Paper I presents a systematic review and meta-analysis of studies that have investigated the role of SPIO for sentinel lymph node biopsy (SLNB). The findings confirm that SPIO performs comparably to radioisotope while highlighting knowledge gaps regarding the optimal dose, timing, and site of SPIO injection to minimize side-effects and facilitate tailoring of treatment.

    Paper II reports a pragmatic, multicenter randomized clinical trial comparing the use of magnetic seed and SPIO to conventional guidewire and SPIO in non-palpable breast tumors. In 426 patients, both methods demonstrated equivalent re-excision rate, SLN detection, and resection ratio. However, the combination of magnetic seed and SPIO resulted in shorter operative times, fewer failed localizations and improved surgical logistics.

    Paper III presents the results of a prospective cohort study that investigated the feasibility and efficacy of SPIO for SLNB in patients undergoing primary systemic therapy (PST) for breast cancer. The results showed that SPIO performed comparably to radioisotope (RI) but detected more sentinel lymph nodes and demonstrated a higher detection rate of metastatic sentinel lymph nodes. The findings suggest that SPIO injection before PST is both feasible and beneficial for enhancing axillary mapping in this patient population, though further studies are needed to refine the optimal timing of administration.

    Paper IV consists of a health economic analysis of the trial from Paper II. It explores the financial implications of the implementation of a magnetic marker compared to the guidewire. Through a cost-minimization approach that considered all direct and indirect costs, the study demonstrated that although the magnetic marker is more expensive as a device, incorporating it in the Swedish healthcare system is more cost-effective than the guidewire.

    List of papers
    1. Evolution and refinement of magnetically guided sentinel lymph node detection in breast cancer: meta-analysis
    Open this publication in new window or tab >>Evolution and refinement of magnetically guided sentinel lymph node detection in breast cancer: meta-analysis
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    2023 (English)In: British Journal of Surgery, ISSN 0007-1323, E-ISSN 1365-2168, Vol. 110, no 4, p. 410-419Article, review/survey (Refereed) Published
    Abstract [en]

    Background: Superparamagnetic iron oxide nanoparticles (SPIO) have been used as a tracer for sentinel lymph node (SLN) localization in breast cancer, demonstrating comparable performance to the combination of radioisotope (RI) and blue dye (BD).

    Methods: A systematic literature search and meta-analysis with subgroup and meta-regression analysis were undertaken to update the available evidence, assess technique evolution, and define knowledge gaps. Recommendations were made using the GRADE approach.

    Results: In 20 comparative studies, the detection rate was 97.5 per cent for SPIO and 96.5 per cent for RI +/- BD (risk ratio 1.006, 95 per cent c.i. 0.992 to 1.019; P = 0.376, high-certainty evidence). Neoadjuvant therapy, injection site, injection volume or nodal metastasis burden did not affect the detection rate, but injection over 24 h before surgery increased the detection rate on meta-regression. Concordance was 99.0 per cent and reverse concordance 97.1 per cent (rate difference 0.003, 95 per cent c.i. -0.009 to 0.015; P = 0.656, high-certainty evidence). Use of SPIO led to retrieval of slightly more SLNs (pooled mean 1.96 versus 1.89) with a higher nodal detection rate (94.1 versus 83.5 per cent; RR 1.098, 1.058 to 1.140; P < 0.001; low-certainty evidence). In meta-regression, injection over 24 h before surgery increased the SPIO nodal yield over that of RI +/- BD. The skin-staining rate was 30.8 per cent (very low-certainty evidence), and possibly prevented with use of smaller doses and peritumoral injection.

    Conclusion: The performance of SPIO is comparable to that of RI +/- BD. Preoperative injection increases the detection rate and nodal yield, without affecting concordance. Whether skin staining and MRI artefacts are reduced by lower dose and peritumoral injection needs to be investigated.

    Place, publisher, year, edition, pages
    Oxford University Press, 2023
    National Category
    Surgery
    Identifiers
    urn:nbn:se:uu:diva-512993 (URN)10.1093/bjs/znac426 (DOI)000901386400001 ()36560842 (PubMedID)
    Available from: 2023-10-02 Created: 2023-10-02 Last updated: 2025-02-19Bibliographically approved
    2. Magnetic Seed vs Guidewire Breast Cancer Localization With Magnetic Lymph Node Detection
    Open this publication in new window or tab >>Magnetic Seed vs Guidewire Breast Cancer Localization With Magnetic Lymph Node Detection
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    2023 (English)In: JAMA Surgery, ISSN 2168-6254, E-ISSN 2168-6262Article in journal (Refereed) Epub ahead of print
    Abstract [en]

    Importance  Guidewires have been the standard for breast lesion localization but pose operative and logistic challenges. Paramagnetic seeds have shown promising results, but to the authors’ knowledge, no randomized comparison has been performed.

    Objective  To determine whether the combination of a paramagnetic seed and superparamagnetic iron oxide (SPIO) is equivalent to guidewire and SPIO for breast cancer localization and sentinel lymph node detection (SLND).

    Design, Setting, and Participants  This was a phase 3, pragmatic, equivalence, 2-arm, open-label, randomized clinical trial conducted at 3 university and/or community hospitals in Sweden from May 2018 to May 2022. Included in the study were patients with early breast cancer planned for breast conservation and SLND. Study data were analyzed July to November 2022.

    Interventions  Participants were randomly assigned 1:1 to a paramagnetic seed or a guidewire. All patients underwent SLND with SPIO.

    Main Outcomes and Measures  Re-excision rate and resection ratio (defined as actual resection volume / optimal resection volume).

    Results  A total of 426 women (median [IQR] age, 65 [56-71] years; median [IQR] tumor size, 11 [8-15] mm) were included in the study. The re-excision rate was 2.90% (95% CI, 1.60%-4.80%), and the median (IQR) resection ratio was 1.96 (1.15-3.44). No differences were found between the guidewire and the seed in re-excisions (6 of 211 [2.84%] vs 6 of 209 [2.87%]; difference, −0.03%; 95% CI, −3.20% to 3.20%; P = .99) or resection ratio (median, 1.93; IQR, 1.18-3.43 vs median, 2.01; IQR, 1.11-3.47; P = .70). Overall SLN detection was 98.6% (95% CI, 97.1%-99.4%) with no differences between arms (203 of 207 [98.1%] vs 204 of 206 [99.0%]; difference, −0.9%; 95% CI, −3.6% to 1.8%; P = .72). More failed localizations occurred with the guidewire (21 of 208 [10.1%] vs 4 of 215 [1.9%]; difference, 8.2%; 95% CI, 3.3%-13.2%; P < .001). Median (IQR) time to specimen excision was shorter for the seed (15 [10-22] minutes vs 18 [12-30] minutes; P = .01), as was the total operative time (69 [56-86] minutes vs 75.5 [59-101] minutes; P = .03). The experience of surgeons, radiologists, and surgical coordinators was better with the seed.

    Conclusions and Relevance  The combination of SPIO and a paramagnetic seed performed comparably with SPIO and guidewire for breast cancer conserving surgery and resulted in more successful localizations, shorter operative times, and better experience.

    Trial Registration  ISRCTN.org Identifier: ISRCTN11914537

    Place, publisher, year, edition, pages
    American Medical Association (AMA), 2023
    National Category
    Surgery Cancer and Oncology
    Identifiers
    urn:nbn:se:uu:diva-524259 (URN)10.1001/jamasurg.2023.6520 (DOI)001134191000002 ()38150215 (PubMedID)
    Funder
    Uppsala UniversityThe Breast Cancer Foundation
    Available from: 2024-02-29 Created: 2024-02-29 Last updated: 2025-02-19Bibliographically approved
    3. Magnetically guided surgery after primary systemic therapy for breast cancer: implications for enhanced axillary mapping
    Open this publication in new window or tab >>Magnetically guided surgery after primary systemic therapy for breast cancer: implications for enhanced axillary mapping
    2024 (English)In: British Journal of Surgery, ISSN 0007-1323, E-ISSN 1365-2168, Vol. 111, no 2, article id znae008Article in journal (Refereed) Published
    Abstract [en]

    Background: Superparamagnetic iron nanoparticles perform comparably to radioisotope +/- blue dye for sentinel lymph node detection in breast cancer, even when injected up to 8 weeks before surgery. Using superparamagnetic iron nanoparticles for sentinel lymph node detection after primary systemic therapy, and the maximum time frame of superparamagnetic iron nanoparticle administration have not been investigated.

    Methods: This cohort study included cN0/1-to-ycN0 patients undergoing sentinel lymph node detection or targeted axillary dissection. All patients received superparamagnetic iron nanoparticles either before primary systemic therapy or before surgery, and radioisotope on the day of surgery.

    Results: For 113 patients analysed, superparamagnetic iron nanoparticles were injected a median of 3 (range 0-248) days before surgery, with a 97.4% detection rate compared with 91.2% for radioisotope (P = 0.057). Concordance for radioisotope was 97.1% and this was not affected by timing of superparamagnetic iron nanoparticle injection (Kendall's tau 0.027; P = 0.746). The median sentinel lymph node yield was 3 (interquartile range (i.q.r.) 2-3) for superparamagnetic iron nanoparticles and 2 (i.q.r. 2-3) for radioisotope (P < 0.001). In targeted axillary dissection, detection was 100% for superparamagnetic iron nanoparticles and 81.8% for radioisotope (P = 0.124). The index node was magnetic in 93.9% and radioactive in 66.7% (P = 0.007), an outcome that was not affected by any factors. For patients with metastases, superparamagnetic iron nanoparticle detection was 100% and radioisotope-based detection was 84.2% (P = 0.083), with superparamagnetic iron nanoparticles detecting more metastatic sentinel lymph nodes (median of 1 (i.q.r. 1-2) for superparamagnetic iron nanoparticles compared with a median of 1 (i.q.r. 0-1) for radioisotope; P = 0.005).

    Conclusion: Injection before primary systemic therapy is feasible and does not affect concordance with radioisotope. Superparamagnetic iron nanoparticles perform comparably to radioisotope, but detect more sentinel lymph nodes and have a higher rate of detection of metastatic sentinel lymph nodes.

    Place, publisher, year, edition, pages
    Oxford University Press, 2024
    National Category
    Radiology, Nuclear Medicine and Medical Imaging Surgery
    Identifiers
    urn:nbn:se:uu:diva-523885 (URN)10.1093/bjs/znae008 (DOI)001158475100001 ()38325801 (PubMedID)
    Available from: 2024-02-26 Created: 2024-02-26 Last updated: 2025-02-19Bibliographically approved
    4. Magnetic seed vs guidewire breast cancer localization with magnetic lymph node detection: a cost-minimization analysis
    Open this publication in new window or tab >>Magnetic seed vs guidewire breast cancer localization with magnetic lymph node detection: a cost-minimization analysis
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Surgery
    Identifiers
    urn:nbn:se:uu:diva-550895 (URN)
    Available from: 2025-02-19 Created: 2025-02-19 Last updated: 2025-02-20
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  • Public defence: 2025-04-11 09:00 H:son Holmdahlsalen, Uppsala
    Hellbacher, Erik
    Uppsala University Hospital.
    Studies on Lymphoma in Rheumatic Diseases and the Pathophysiology of ANCA-Associated Vasculitis2025Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Patients with rheumatic diseases are at increased risk of developing malignant lymphoma, yet the mechanisms linking immune-mediated diseases to lymphomagenesis remain unclear. A deeper understanding of these processes could provide clues to the pathogenesis of both disease categories, improve early risk assessment, and inform preventive strategies. Similarly, the pathophysiological mechanisms of ANCA-associated vasculitis (AAV) and the molecular distinctions underlying the varied clinical outcomes of its subtypes, granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA), remain poorly understood. Improved insights into these mechanisms could aid in developing more targeted diagnostic tools and treatment strategies.

    Paper I investigated B cell-related mechanisms in rheumatoid arthritis (RA)-associated diffuse large B-cell lymphoma (DLBCL). Key findings include elevated levels of several cytokines and chemokines relevant to B-cell biology compared to RA and population controls. In particular, CXCL13 emerged as a protein of interest for its potential role in linking RA to lymphomagenesis.

    Paper II examined programmed cell death protein 1 (PD-1) and its ligands PD-L1 and PD-L2 in lymphoma tissue from patients with pre-existing rheumatic diseases, with a particular focus on RA-associated DLBCL. A key finding suggests that RA disease severity may influence PD-L1 expression in DLBCL tumor cells.

    Paper III characterized lymphomas in patients with pre-existing GPA, focusing on subtypes, localization, and clinical features of both the lymphomas and the underlying rheumatic disease. No clear indications of a predominance of a specific lymphoma subtype were observed, nor was there evidence suggesting local lymphomagenesis in typical GPA target organs.

    Paper IV identified key proteins, biological functions, and pathways associated with both shared and distinct disease mechanisms in AAV subtypes, categorized by ANCA serotype into proteinase 3 (PR3)-AAV and myeloperoxidase (MPO)-AAV. The findings highlighted enhanced STAT3 signaling in PR3-AAV and prominent TNF signaling in MPO-AAV, suggesting partially distinct inflammatory processes driving the pathogenesis of these subtypes.

    To conclude, the studies in this thesis contribute to the efforts to elucidate the link between autoimmune diseases and lymphoma, as well as the shared and distinct disease mechanisms in AAV.

    List of papers
    1. Diffuse large B cell lymphoma in rheumatoid arthritis patients is associated with elevated B-cell driving factors including CXCL13
    Open this publication in new window or tab >>Diffuse large B cell lymphoma in rheumatoid arthritis patients is associated with elevated B-cell driving factors including CXCL13
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Rheumatology
    Identifiers
    urn:nbn:se:uu:diva-550848 (URN)
    Available from: 2025-02-19 Created: 2025-02-19 Last updated: 2025-02-19
    2. Expression of PD-1, PD-L1 and PD-L2 in Lymphomas in Patients with Pre-Existing Rheumatic Diseases-A Possible Association with High Rheumatoid Arthritis Disease Activity
    Open this publication in new window or tab >>Expression of PD-1, PD-L1 and PD-L2 in Lymphomas in Patients with Pre-Existing Rheumatic Diseases-A Possible Association with High Rheumatoid Arthritis Disease Activity
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    2022 (English)In: Cancers, ISSN 2072-6694, Vol. 14, no 6, article id 1509Article in journal (Refereed) Published
    Abstract [en]

    Simple Summary Immunotherapy blocking programmed cell death protein 1 (PD-1) and its ligands (PD-L1, PD-L2) is less effective in non-Hodgkin lymphoma (NHL) than classical Hodgkin lymphoma. However, NHL is a heterogeneous group and current research seeks to identify subgroups of NHL patients responsive to PD-1 blocking agents. Whether patients with pre-existing rheumatic diseases might constitute such a subgroup is unknown. We investigated the expression of PD-1 and its ligands in lymphoma patients with pre-existing rheumatic diseases. Our key findings include that in patients with pre-existing rheumatoid arthritis (RA) and subsequent diffuse large B-cell lymphoma, an association between RA disease severity and increased expression of PD-L1 in tumor cells was seen. This warrants further studies of the PD-1 pathway in lymphoma in other chronic inflammatory conditions. Current research seeks to identify subgroups of non-Hodgkin lymphoma (NHL) patients responsive to PD-1 blocking agents. Whether patients with pre-existing rheumatic diseases might constitute such a subgroup is unknown. We determined intratumoral expression of PD-1 and its ligands in lymphoma patients with pre-existing rheumatic diseases. We included 215 patients with rheumatoid arthritis (RA), systemic lupus erythematosus (SLE) or Sjogren's syndrome with subsequent lymphoma and 74 diffuse large B-cell lymphoma (DLBCL) controls without rheumatic disease. PD-1 and PD-ligand immunohistochemical markers were applied on tumor tissue microarrays. The number of PD-1+ tumor infiltrating leukocytes (TILs) and proportions of PD-L1+ and PD-L2+ tumor cells and TILs were calculated and correlated with clinical data. Expression of PD-L1 in tumor cells and TILs was highest in classical Hodgkin lymphoma and DLBCL. In DLBCLs, expression of PD-1 in TILs and PD-L1 in tumor cells was similar in RA, SLE and controls. In RA-DLBCL, high expression of PD-L1 in tumor cells was significantly more common in patients with the most severe RA disease and was associated with inferior overall survival in multivariable analysis.

    Place, publisher, year, edition, pages
    MDPIMDPI, 2022
    Keywords
    lymphoma, PD-1, PD-L1, rheumatic disease, immunohistochemistry
    National Category
    Clinical Medicine Cancer and Oncology
    Identifiers
    urn:nbn:se:uu:diva-472740 (URN)10.3390/cancers14061509 (DOI)000775837000001 ()35326658 (PubMedID)
    Available from: 2022-04-19 Created: 2022-04-19 Last updated: 2025-02-19Bibliographically approved
    3. Malignant lymphoma in granulomatosis with polyangiitis: subtypes, clinical characteristics and prognosis
    Open this publication in new window or tab >>Malignant lymphoma in granulomatosis with polyangiitis: subtypes, clinical characteristics and prognosis
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    2019 (English)In: Acta Oncologica, ISSN 0284-186X, E-ISSN 1651-226X, Vol. 58, no 11, p. 1655-1659Article in journal, Letter (Other academic) Published
    Abstract [en]

    Several autoimmune and inflammatory conditions, such as rheumatoid arthritis (RA) and primary Sjögrens’s syndrome (pSS), have repeatedly been linked to an increased risk of malignant lymphoma [1,2]. Certain inflammatory conditions are also associated with the development of specific lymphoma subtypes such as mucosa-associated lymphoid tissue (MALT) lymphoma in pSS and diffuse large B-cell lymphoma (DLBCL) in RA. The underlying mechanisms behind this association remain unclear. The highly increased risk of developing MALT lymphoma of the parotid gland in pSS indicates that local inflammatory processes can promote lymphoma development at the site of chronic inflammation [3]. In RA, an association between disease severity and risk of lymphoma has been shown.

    Granulomatosis with polyangiitis (GPA), formerly Wegener’s granulomatosis, is a systemic small vessel vasculitis associated with the presence of anti-neutrophil cytoplasmic antibodies (ANCA) and characterized by granulomatous inflammation and necrotizing vasculitis of the airways and kidneys but possibly affecting any organ system. An increased risk of lymphoma in patients with GPA has been reported in several epidemiological studies [4,5]. However, very little is known about risk factors for lymphoma development in this group, possible relation to disease severity, treatment and lymphoma subtypes or the prognosis for the lymphomas. This is the first published study on GPA and lymphoma, giving detailed information on the GPA characteristics and possible risk factors for lymphoma and also lymphoma subtypes treatment and survival.

    National Category
    Cancer and Oncology Clinical Laboratory Medicine
    Research subject
    Pathology
    Identifiers
    urn:nbn:se:uu:diva-398532 (URN)10.1080/0284186X.2019.1634833 (DOI)000481027700001 ()31407922 (PubMedID)
    Funder
    Swedish Cancer Society
    Available from: 2019-12-06 Created: 2019-12-06 Last updated: 2025-02-19Bibliographically approved
    4. The plasma proteome reveals distinct signaling pathways associated with PR3-ANCA positive and MPO-ANCA positive vasculitis
    Open this publication in new window or tab >>The plasma proteome reveals distinct signaling pathways associated with PR3-ANCA positive and MPO-ANCA positive vasculitis
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    (English)Manuscript (preprint) (Other academic)
    National Category
    Medical and Health Sciences Rheumatology
    Identifiers
    urn:nbn:se:uu:diva-550876 (URN)
    Available from: 2025-02-19 Created: 2025-02-19 Last updated: 2025-02-19
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  • Public defence: 2025-04-11 09:15 Sal IX,Universitetshuset, Uppsala
    Hohenthal, Christian
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of History.
    Textens ritualer och historieskrivningens gränser: En undersökning av fyra svenska historieverk från 1400- och 1500-talen2025Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The fifteenth and sixteenth centuries witnessed a flourishing of history writing by Swedish authors. This thesis studies four such historical works, namely the Karlskrönika (c. 1452), Ericus Olai’s Chronica regni Gothorum (c. 1471), the Sturekrönika (c. 1497), and Johannes Magnus’s Historia metropolitanae ecclesiae Upsalensis (1536/1557). 

    The aim of the study is to elucidate how the authors made use of three forms of ritualised occurrences to comment on the legitimacy of both secular and spiritual leaders. In order to do this, the thesis analyses ritualised time, elec­tions, and funerals. Historians have noted that depictions of rituals in medieval history writing were highly susceptible to politically and ideologically mo­tivated modifications—or even completely invented. In relation to Swedish historio­graphy of the fifteenth and sixteenth centuries this topic has, however, previously received limited scholarly interest. Furthermore, by comparing the authors’ accounts with the sources they likely used, the thesis also endeavours to shed light on how and to what degree the authors shaped their accounts to conform to their political and ideological outlook. 

    The study shows that authors used ritualised occurrences to thematise the legitimacy of leaders, which is in line with previous observations. In relation to earlier research, the thesis presents a more thorough analysis of what this meant in practice and the nuances and ambiguities connected to these descrip­tions. Generally speaking, these ritualised occurrences provided authors with an opportunity to illustrate the connection between the leader and common­weal of the realm and/or the Church. The analysis shows that there were a variety of ways in which authors could “spin” such occurrences and connect them to specific values that ultimately related to the common good. Not least, the study demonstrates that the descriptions of emotions and frames of mind were important tools when authors gave meaning to these retellings of the past. The analysis also suggests that authors were reluctant to engage in pure invention, at least when writing about ritualised occurrences pertaining to a more recent past. 

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