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  • 252401.
    Öjefors, Erik
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Signal Processing. Signals and systems.
    Sönmez, E
    Chartier, S
    Lindberg, Peter
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Signal Processing. Signals and systems.
    Rydberg, Anders
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences, Signal Processing. Signals and systems.
    Schumacher, H
    Monolithic integration of an antenna with a 24 GHz image-rejection receiver in SiGe HBT technology2005In: 35th European Microwave Conference (EuMC), 2005Conference paper (Refereed)
  • 252402.
    Öjefors, Erik
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences.
    Sönmez, Ertugrul
    Chartier, Sebastien
    Lindberg, Peter
    Rydberg, Anders
    Schumacher, Hermann
    Monolithic Integration of an Antenna with a 24 GHz Image-Rejection Receiver in SiGE HBT Technology2005In: Proceeding of the 35th European MIcrowave Conference, 2005Chapter in book (Other academic)
  • 252403.
    Öjefors, Erik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Signal Processing.
    Sönmez, Ertugrul
    Chartier, Sebastien
    Lindberg, Peter
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Signal Processing.
    Schick, Christoph
    Rydberg, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Signal Processing.
    Schumacher, Hermann
    Monolithic Integration of a Folded Dipole Antenna With a 24-GHz Receiver in SiGe HBT Technology2007In: IEEE transactions on microwave theory and techniques, ISSN 0018-9480, E-ISSN 1557-9670, Vol. 55, no 7, p. 1467-1475Article in journal (Refereed)
    Abstract [en]

    The integration of an on-chip folded dipole antenna with a monolithic 24-GHz receiver manufactured in a 0.8-mum SiGe HBT process is presented. A high-resistivity silicon substrate (1000 Omega ldr cm) is used for the implemented circuit to improve the efficiency of the integrated antenna. Crosstalk between the antenna and spiral inductors is analyzed and isolation techniques are described. The receiver, including the receive and an optional transmit antenna, requires a chip area of 4.5 mm2 and provides 30-dB conversion gain at 24 GHz with a power consumption of 960 mW.

  • 252404.
    Öjemar, Peter
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Law, Department of Law.
    Fastighetsbildning i strandnära områden: En analys av miljörättslig påverkan av fastighetsbildningsåtgärder2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 252405.
    Öjteg, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine.
    Permeability of renal capillaries1986Doctoral thesis, comprehensive summary (Other academic)
  • 252406.
    Ökvist, Alice
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Pavlovic, Anica
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Management Control Systems and their Connection to Exceptional Growth: an internal perspective2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This paper is concerned with the use of management control systems (MCSs) within high growth firms (HGFs) to support rapid growth. Considering that a lack of MCSs has been identified as a major cause of failure among start-ups, as well as that MCSs have been claimed to enable firms to grow more during their early years, this is a highly interesting topic for scholars as well as entrepreneurs. However, despite the exceptional opportunity that HGFs provide in examining this topic, there is a lack of contemporary research on how HGFs use MCSs to support their growth. To fill this gap a multiple case study was conducted, investigating how Simons’ (1995) levers of control were used to support growth within 12 different HGFs. Through drawing upon data from interviews with 19 different key people it was then found that MCSs support growth in various ways. Different boundary systems were found to increase chances of firm survival and provide a platform for growth. Additionally, the use of interactive systems was identified as a potential characteristic of HGFs. Moreover, the research questions former assumptions on the importance of forecasting.

  • 252407.
    Ökvist, Anna
    et al.
    The Section of Alcohol and Drug Dependence Research, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden.
    Johansson, Sofia
    The Section of Alcohol and Drug Dependence Research, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden.
    Kuzmin, Alexander
    The Section of Alcohol and Drug Dependence Research, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden.
    Bazov, Igor
    The Section of Alcohol and Drug Dependence Research, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden.
    Merino-Martinez, Roxana
    Department of Molecular Medicine, Karolinska Institute, Stockholm, Sweden.
    Ponomarev, Igor
    Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, Texas, United States of America.
    Mayfield, R. Dayne
    Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, Texas, United States of America.
    Harris, R. Adron
    Waggoner Center for Alcohol and Addiction Research, University of Texas at Austin, Austin, Texas, United States of America.
    Sheedy, Donna
    Discipline of Pathology, University of Sydney, Sydney, New South Wales, Australia.
    Garrick, Therese
    Discipline of Pathology, University of Sydney, Sydney, New South Wales, Australia.
    Harper, Clive
    Discipline of Pathology, University of Sydney, Sydney, New South Wales, Australia.
    Hurd, Yasmin L.
    Department of Psychiatry, Mount Sinai School of Medicine, New York, New York, United States of America and Department of Pharmacology and Biological Chemistry, Mount Sinai School of Medicine, New York, New York, United States of America.
    Terenius, Lars
    The Section of Alcohol and Drug Dependence Research, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden.
    Ekström, Tomas J.
    The Section of Alcohol and Drug Dependence Research, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden.
    Bakalkin, Georgy
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmaceutical Biosciences, Biological Research on Drug Dependence.
    Yakovleva, Tatjana
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmaceutical Biosciences, Biological Research on Drug Dependence.
    Neuroadaptations in human chronic alcoholics: dysregulation of the NF-κB system2007In: PLoS ONE, ISSN 1932-6203, Vol. 2, no 9, p. e930-Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Alcohol dependence and associated cognitive impairments apparently result from neuroadaptations to chronic alcohol consumption involving changes in expression of multiple genes. Here we investigated whether transcription factors of Nuclear Factor-kappaB (NF-kappaB) family, controlling neuronal plasticity and neurodegeneration, are involved in these adaptations in human chronic alcoholics. METHODS AND FINDINGS: Analysis of DNA-binding of NF-kappaB (p65/p50 heterodimer) and the p50 homodimer as well as NF-kappaB proteins and mRNAs was performed in postmortem human brain samples from 15 chronic alcoholics and 15 control subjects. The prefrontal cortex involved in alcohol dependence and cognition was analyzed and the motor cortex was studied for comparison. The p50 homodimer was identified as dominant kappaB binding factor in analyzed tissues. NF-kappaB and p50 homodimer DNA-binding was downregulated, levels of p65 (RELA) mRNA were attenuated, and the stoichiometry of p65/p50 proteins and respective mRNAs was altered in the prefrontal cortex of alcoholics. Comparison of a number of p50 homodimer/NF-kappaB target DNA sites, kappaB elements in 479 genes, down- or upregulated in alcoholics demonstrated that genes with kappaB elements were generally upregulated in alcoholics. No significant differences between alcoholics and controls were observed in the motor cortex. CONCLUSIONS: We suggest that cycles of alcohol intoxication/withdrawal, which may initially activate NF-kappaB, when repeated over years downregulate RELA expression and NF-kappaB and p50 homodimer DNA-binding. Downregulation of the dominant p50 homodimer, a potent inhibitor of gene transcription apparently resulted in derepression of kappaB regulated genes. Alterations in expression of p50 homodimer/NF-kappaB regulated genes may contribute to neuroplastic adaptation underlying alcoholism.

  • 252408.
    Ökvist, Nicklas
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Informatics and Media.
    Furberg, Max
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Informatics and Media.
    Analysmodell för inbyggt dataskydd och dataskydd som standard2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 252409.
    Ökvist, Sofia
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Clausén, Frida
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Värdering av förvaltningsfastigheter: Hur tillförlitlig är verkligt värdemetoden?2009Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Införandet av IAS 40 medförde förändringar vad gäller värderingen av förvaltningsfastigheter. Fastighetsbolagen fick då möjlighet att värdera sina fastigheter till verkligt värde, vilket skapade en problematik vad gäller tillförlitligheten i värderingen.

    Syftet med uppsatsen är att undersöka tillförlitligheten i värderingen av förvaltningsfastigheter. Detta påverkas av ett flertal faktorer som alla har betydelse för värderingens tillförlitlighet. Syftet kommer att uppfyllas genom att belysa begreppet tillförlitlighet utifrån ett antal påverkande faktorer.

    För att undersöka detta har vi genomfört fyra intervjuer med respondenter från fastighetsbolag, en extern värderingsman samt en redovisningsspecialist inom området. Urvalet av intervjurespondenter har skett genom en studie av Sveriges största noterade fastighetsbolag, där hänsyn tagits till vissa utvalda parametrar. Intervjufrågor har utformats utifrån analysmodellen som sedan har legat till grund för uppsatsens empiriavsnitt samt analys.

    I uppsatsen dras slutsatsen att tillförlitligheten vid värderingen av förvaltningsfastigheter till verkligt värde är låg. Detta kan dock förbättras med hjälp av en större mängd presenterad information vad gäller värderingsmodellerna som används, för att därmed öka företagens transparens. På så sätt kan externa intressenter på egen hand avgöra hur tillförlitlig de anser att värderingen i själva verket är.

  • 252410.
    Ölander, Caroline
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Educational Sciences, Department of Education.
    Olausson Johansson, Maria
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Educational Sciences, Department of Education.
    Förskollärares förhållningssätt till inkludering av barn med Downs syndrom2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med denna studie var att undersöka hur pedagogerna såg på sitt förhållningssätt samt hur de arbetade för att få en fungerande inkludering för barn med Downs syndrom. Vi ville se vilka svårigheter som kunde förekomma samt hur pedagogen förhöll sig till denna inkludering undersöktes också. I denna studie beskrivs olika hjälpmedel som används i verksamheten för att stödja och förenkla inkluderingen för barn med Downs syndrom. De metoder som användes i detta arbete var semistrukturerade samt strukturerad intervjuer samt strukturerade observationer. Vår teoretiska utgångspunkt i detta arbeta har varit inkludering och Vygotskijs teori har varit vägledande i denna studie. I denna studie har vi kommit fram till att pedagogerna har en betydande roll för inkluderingen mellan barnen. Andra faktorer som spelar en stor roll för inkluderingen är även den pedagogiska miljön samt den sociala samvaron. 

  • 252411.
    Ölander, Christine
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Otolaryngology and Head and Neck Surgery.
    Gudjonsson, Olafur
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Neurosurgery.
    Kinnefors, Anders
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Otolaryngology and Head and Neck Surgery.
    Laurell, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Otolaryngology and Head and Neck Surgery.
    Edfeldt, Lennart
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Otolaryngology and Head and Neck Surgery.
    Complications in translabyrinthine surgery of vestibular schwannoma2018In: Acta Oto-Laryngologica, ISSN 0001-6489, E-ISSN 1651-2251, Vol. 138, no 7, p. 639-645Article in journal (Refereed)
    Abstract [en]

    Objective: To evaluate the risk of complications associated with tumor size and patient's age in translabyrinthine vestibular schwannoma surgery. Methods: 700 patients with vestibular schwannoma primarily underwent translabyrinthine surgery between 1988 and 2014. Pre- and postoperative data were collected in a database and incidence of the postoperative complications cerebrospinal fluid leakage, meningitis, intracranial hemorrhage (ICH), facial nerve function and mortality were assessed and related to the tumor size and patient's age and retrospectively evaluated. Results: The tumor size significantly influenced the incidence of ICH and facial nerve dysfunction whereas age was correlated to facial nerve outcome. Conclusions: The translabyrinthine approach is a safe surgical procedure with relatively low risks of complications. The tumor size was significantly associated with a higher risk of ICH and facial nerve dysfunction whereas age only influenced the facial nerve outcome.

  • 252412.
    Ölander, Magnus
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Proteomic and Functional Analysis of In Vitro Systems for Studies of Drug Disposition in the Human Small Intestine and Liver2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    To reach the bloodstream, an orally administered drug must be absorbed through the small intestine and avoid extensive clearance in the liver. Estimating these parameters in vitro is therefore important in drug discovery and development. This can be achieved with cellular models that simulate human organ function, such as Caco-2 cells and primary hepatocytes. No model fits every scenario, however, and this thesis aimed at using proteomic and functional analysis to better understand and increase the applicability of in vitro models based on Caco-2 cells and human hepatocytes.

    First, the proteome of filter-grown Caco-2 cells was analyzed. This included near-complete coverage of enterocyte-related proteins, and over 300 ADME proteins. Further, by scaling uptake transport kinetics from Caco-2 cells to human jejunum, the importance of considering in vitro­-in vivo expression differences to correctly interpret in vitro transport studies was demonstrated.

    Focus was then turned to hepatocytes, where proteomics was used as a basis for the successful development of an apoptosis inhibition protocol for restoration of attachment properties and functionality in suboptimal batches of cryopreserved human hepatocytes. As a spin-off project, image-based quantification of cell debris was developed into a novel apoptosis detection method.

    Next, the in vivo heterogeneity of human hepatocytes was explored in an in vitro setting, where it was observed that human hepatocyte batches contain a wide range of cell sizes. By separating the cells into different size fractions, it was found that hepatocyte size corresponds to the microarchitectural zone of origin in the liver. Size separation can thus be used to study zonated liver functions in vitro.

    Finally, the proteomes of the major types of non-parenchymal liver cells were analyzed, i.e. liver sinusoidal endothelial cells, Kupffer cells, and hepatic stellate cells. The different cell types all had distinctly different proteomes, and the expression of certain important ADME proteins indicated that non-parenchymal cells participate in drug disposition.

    In conclusion, this thesis has improved the phenotypic understanding and extended the applicability of Caco-2 cells and primary human hepatocytes, two of the most important in vitro models for studies of small intestinal and hepatic drug disposition.

    List of papers
    1. The Proteome of Filter-Grown Caco-2 Cells With a Focus on Proteins Involved in Drug Disposition
    Open this publication in new window or tab >>The Proteome of Filter-Grown Caco-2 Cells With a Focus on Proteins Involved in Drug Disposition
    Show others...
    2016 (English)In: Journal of Pharmaceutical Sciences, ISSN 0022-3549, E-ISSN 1520-6017, Vol. 105, no 2, p. 817-827Article in journal (Refereed) Published
    Abstract [en]

    Caco-2 cells are widely used in studies of intestinal cell physiology and drug transport. Here, the global proteome of filter-grown Caco-2 cells was quantified using the total protein approach and compared with the human colon and jejunum proteomes. In total, 8096 proteins were identified. In-depth analysis of proteins defining enterocyte differentiation—including brush-border hydrolases, integrins, and adherens and tight junctions—gave near-complete coverage of the expected proteins. Three hundred twenty-seven absorption, distribution, metabolism and excretion proteins were identified, including 112 solute carriers and 20 ATP-binding cassette transporters. OATP2B1 levels were 16-fold higher in Caco-2 cells than in jejunum. To investigate the impact of this difference on in vitro-in vivo extrapolations, we studied the uptake kinetics of the OATP2B1 substrate pitavastatin in Caco-2 monolayers, and found that the contribution of OATP2B1 was 60%-70% at clinically relevant intestinal concentrations. Pitavastatin kinetics was combined with transporter concentrations to model the contribution of active transport and membrane permeation in the jejunum. The lower OATP2B1 expression in jejunum led to a considerably lower transporter contribution (<5%), suggesting that transmembrane diffusion dominates pitavastatin absorption in vivo. In conclusion, we present the first in-depth quantification of the filter-grown Caco-2 proteome. We also demonstrate the crucial importance of considering transporter expression levels for correct interpretation of drug transport routes across the human intestine.

    National Category
    Pharmaceutical Sciences
    Identifiers
    urn:nbn:se:uu:diva-277281 (URN)10.1016/j.xphs.2015.10.030 (DOI)000381768500048 ()26869432 (PubMedID)
    Funder
    Swedish Research Council, 2822Carl Tryggers foundation
    Available from: 2016-02-18 Created: 2016-02-18 Last updated: 2019-04-24Bibliographically approved
    2. A simple approach for restoration of differentiation and function in cryopreserved human hepatocytes
    Open this publication in new window or tab >>A simple approach for restoration of differentiation and function in cryopreserved human hepatocytes
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    2019 (English)In: Archives of Toxicology, ISSN 0340-5761, E-ISSN 1432-0738, Vol. 93, no 3, p. 819-829Article in journal (Refereed) Published
    Abstract [en]

    Primary human hepatocytes are used in all facets of liver research, from in vitro studies of xenobiotic disposition and toxicity to the clinical management of liver failure. Unfortunately, cellular stress during isolation and cryopreservation causes a highly unpredictable loss of the ability to attach and form cell-matrix and cell-cell interactions. Reasoning that this problem could be mitigated at the post-thawing stage, we applied label-free quantitative global proteomics to analyze differences between attached and non-attached fractions of cryopreserved human hepatocyte batches. Hepatocytes that were unable to attach to a collagen matrix showed many signs of cellular stress, including a glycolytic phenotype and activation of the heat shock response, ultimately leading to apoptosis activation. Further analysis of the activated stress pathways revealed an increase in early apoptosis immediately post-thawing, which suggested the possibility of stress reversal. Therefore, we transiently treated the cells with compounds aimed at decreasing cellular stress via different mechanisms. Brief exposure to the pan-caspase apoptosis inhibitor Z-VAD-FMK restored attachment ability and promoted a differentiated morphology, as well as formation of 3D spheroids. Further, Z-VAD-FMK treatment restored metabolic and transport functions, with maintained sensitivity to hepatotoxic insults. Altogether, this study shows that differentiation and function of suboptimal human hepatocytes can be restored after cryopreservation, thus markedly increasing the availability of these precious cells.

    Keywords
    Apoptosis, Cellular stress, Cryopreservation, Hepatotoxicity, Human hepatocytes, Proteomics
    National Category
    Pharmaceutical Sciences
    Identifiers
    urn:nbn:se:uu:diva-372723 (URN)10.1007/s00204-018-2375-9 (DOI)000463730100019 ()30560367 (PubMedID)
    Funder
    Swedish Research Council, 2822Swedish Research Council, 01951
    Available from: 2019-01-08 Created: 2019-01-08 Last updated: 2019-04-30Bibliographically approved
    3. Image-based quantification of cell debris as a measure of apoptosis
    Open this publication in new window or tab >>Image-based quantification of cell debris as a measure of apoptosis
    2019 (English)In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 91, no 9, p. 5548-5552Article in journal (Refereed) Published
    Abstract [en]

    Apoptosis is a controlled form of cell death that can be induced by various diseases and exogenous toxicants. Common apoptosis detection methods rely on fluorescent markers, which necessitates the use of costly reagents and time-consuming labeling procedures. Label-free methods avoid these problems, but often require specialized instruments instead. Here, we utilize apoptotic cell disintegration to develop a novel label-free detection method based on the quantification of subcellular debris particles in bright-field microscopy images. Debris counts show strong correlations with fluorescence-based annexin V staining, and can be used to study concentration-dependent and temporal apoptosis activation. The method is rapid, low-cost, and easy to apply, as the only experimental step comprises bright-field imaging of culture media samples, followed by automated image processing. The late-stage nature of the debris measurement means that the method can complement other, established apoptosis assays, and its accessibility will allow a wider community of researchers to study apoptotic cell death.

    National Category
    Pharmaceutical Sciences Analytical Chemistry
    Identifiers
    urn:nbn:se:uu:diva-382403 (URN)10.1021/acs.analchem.9b01243 (DOI)000467642100015 ()31001971 (PubMedID)
    Funder
    Swedish Research Council, 2822Swedish Research Council, 01951
    Available from: 2019-04-24 Created: 2019-04-24 Last updated: 2019-06-19Bibliographically approved
    4. Hepatocyte size fractionation allows dissection of human liver zonation
    Open this publication in new window or tab >>Hepatocyte size fractionation allows dissection of human liver zonation
    Show others...
    (English)Manuscript (preprint) (Other academic)
    National Category
    Pharmaceutical Sciences
    Identifiers
    urn:nbn:se:uu:diva-382404 (URN)
    Funder
    Swedish Research Council, 2822, 01951
    Available from: 2019-04-24 Created: 2019-04-24 Last updated: 2019-04-24
    5. Proteomic analysis of major cell types in the human liver
    Open this publication in new window or tab >>Proteomic analysis of major cell types in the human liver
    (English)Manuscript (preprint) (Other academic)
    National Category
    Pharmaceutical Sciences
    Identifiers
    urn:nbn:se:uu:diva-382405 (URN)
    Funder
    Swedish Research Council, 01951
    Available from: 2019-04-24 Created: 2019-04-24 Last updated: 2019-04-24
  • 252413.
    Ölander, Magnus
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Handin, Niklas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Artursson, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Image-based quantification of cell debris as a measure of apoptosis2019In: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 91, no 9, p. 5548-5552Article in journal (Refereed)
    Abstract [en]

    Apoptosis is a controlled form of cell death that can be induced by various diseases and exogenous toxicants. Common apoptosis detection methods rely on fluorescent markers, which necessitates the use of costly reagents and time-consuming labeling procedures. Label-free methods avoid these problems, but often require specialized instruments instead. Here, we utilize apoptotic cell disintegration to develop a novel label-free detection method based on the quantification of subcellular debris particles in bright-field microscopy images. Debris counts show strong correlations with fluorescence-based annexin V staining, and can be used to study concentration-dependent and temporal apoptosis activation. The method is rapid, low-cost, and easy to apply, as the only experimental step comprises bright-field imaging of culture media samples, followed by automated image processing. The late-stage nature of the debris measurement means that the method can complement other, established apoptosis assays, and its accessibility will allow a wider community of researchers to study apoptotic cell death.

  • 252414.
    Ölander, Magnus
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Wegler, Christine
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy. Cardiovascular, Renal and Metabolism, Innovative Medicines and Early Development Biotech Unit, AstraZeneca, Gothenburg, Sweden.
    Treyer, Andrea
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Flörkemeier, Inken
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Handin, Niklas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Pedersen, Jenny M.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Vildhede, Anna
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Mateus, André
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    LeCluyse, Edward L.
    LifeNet Health, Research Triangle Park, North Carolina, USA.
    Urdzik, Jozef
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences.
    Artursson, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Hepatocyte size fractionation allows dissection of human liver zonationManuscript (preprint) (Other academic)
  • 252415.
    Ölander, Magnus
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Wisniewski, Jacek
    Max Planck Inst Biochem, Dept Prote & Signal Transduct, Martinsried, Germany..
    Norén, Agneta
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Upper Abdominal Surgery.
    Artursson, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    To attach or not to attach: factors behind variable adhesion properties of cryopreserved human hepatocytes2016In: Drug metabolism reviews (Softcover ed.), ISSN 0360-2532, E-ISSN 1097-9883, Vol. 48, p. 103-103Article in journal (Other academic)
  • 252416.
    Ölander, Magnus
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Wiśniewski, Jacek R.
    Biochemical Proteomics Group, Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, D-82152, Martinsried, Germany.
    Artursson, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Proteomic analysis of major cell types in the human liverManuscript (preprint) (Other academic)
  • 252417.
    Ölander, Magnus
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Wiśniewski, Jacek R.
    Max Planck Inst Biochem, Biochem Prote Grp, Dept Prote & Signal Transduct, D-82152 Martinsried, Germany.
    Flörkemeier, Inken
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Handin, Niklas
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Urdzik, Jozef
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Upper Abdominal Surgery.
    Artursson, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy. Uppsala University, Science for Life Laboratory, SciLifeLab.
    A simple approach for restoration of differentiation and function in cryopreserved human hepatocytes2019In: Archives of Toxicology, ISSN 0340-5761, E-ISSN 1432-0738, Vol. 93, no 3, p. 819-829Article in journal (Refereed)
    Abstract [en]

    Primary human hepatocytes are used in all facets of liver research, from in vitro studies of xenobiotic disposition and toxicity to the clinical management of liver failure. Unfortunately, cellular stress during isolation and cryopreservation causes a highly unpredictable loss of the ability to attach and form cell-matrix and cell-cell interactions. Reasoning that this problem could be mitigated at the post-thawing stage, we applied label-free quantitative global proteomics to analyze differences between attached and non-attached fractions of cryopreserved human hepatocyte batches. Hepatocytes that were unable to attach to a collagen matrix showed many signs of cellular stress, including a glycolytic phenotype and activation of the heat shock response, ultimately leading to apoptosis activation. Further analysis of the activated stress pathways revealed an increase in early apoptosis immediately post-thawing, which suggested the possibility of stress reversal. Therefore, we transiently treated the cells with compounds aimed at decreasing cellular stress via different mechanisms. Brief exposure to the pan-caspase apoptosis inhibitor Z-VAD-FMK restored attachment ability and promoted a differentiated morphology, as well as formation of 3D spheroids. Further, Z-VAD-FMK treatment restored metabolic and transport functions, with maintained sensitivity to hepatotoxic insults. Altogether, this study shows that differentiation and function of suboptimal human hepatocytes can be restored after cryopreservation, thus markedly increasing the availability of these precious cells.

  • 252418.
    Ölander, Magnus
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Wiśniewski, Jacek R.
    Max Planck Inst Biochem, Biochem Prote Grp, Dept Prote & Signal Transduct, D-82152 Martinsried, Germany.
    Matsson, Pär
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Lundquist, Patrik
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Artursson, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy. Uppsala University, Science for Life Laboratory, SciLifeLab. Uppsala Univ, Drug Optimizat & Pharmaceut Profiling Platform, S-75123 Uppsala, Sweden.
    The Proteome of Filter-Grown Caco-2 Cells With a Focus on Proteins Involved in Drug Disposition2016In: Journal of Pharmaceutical Sciences, ISSN 0022-3549, E-ISSN 1520-6017, Vol. 105, no 2, p. 817-827Article in journal (Refereed)
    Abstract [en]

    Caco-2 cells are widely used in studies of intestinal cell physiology and drug transport. Here, the global proteome of filter-grown Caco-2 cells was quantified using the total protein approach and compared with the human colon and jejunum proteomes. In total, 8096 proteins were identified. In-depth analysis of proteins defining enterocyte differentiation—including brush-border hydrolases, integrins, and adherens and tight junctions—gave near-complete coverage of the expected proteins. Three hundred twenty-seven absorption, distribution, metabolism and excretion proteins were identified, including 112 solute carriers and 20 ATP-binding cassette transporters. OATP2B1 levels were 16-fold higher in Caco-2 cells than in jejunum. To investigate the impact of this difference on in vitro-in vivo extrapolations, we studied the uptake kinetics of the OATP2B1 substrate pitavastatin in Caco-2 monolayers, and found that the contribution of OATP2B1 was 60%-70% at clinically relevant intestinal concentrations. Pitavastatin kinetics was combined with transporter concentrations to model the contribution of active transport and membrane permeation in the jejunum. The lower OATP2B1 expression in jejunum led to a considerably lower transporter contribution (<5%), suggesting that transmembrane diffusion dominates pitavastatin absorption in vivo. In conclusion, we present the first in-depth quantification of the filter-grown Caco-2 proteome. We also demonstrate the crucial importance of considering transporter expression levels for correct interpretation of drug transport routes across the human intestine.

  • 252419.
    Ölfvingsson, Manne
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Social and Economic Geography.
    Varför spårväg i Uppsala?: En kvalitativ studie av spårvägsprojektet i Uppsala2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med uppsatsen är att undersöka spårvägsprojektet i Uppsala. Studien ska identifiera de huvudsakliga faktorerna som har varit avgörande för valet av spårväg. Det studeras även hur projektets beslutsfattare resonerar kring en spårväg utifrån de tre hållbarhetsaspekterna och hur privatbilismen förväntas påverkas. Genom intervjuer med tjänstemän och politiker ska studiens frågeställningar besvaras. Intervjusvaren kompletteras med tidigare forskning inom ämnesområdet och styrdokument från Uppsala kommun. Resultatet visar att kapaciteten är en av de viktigaste faktorerna bakom valet av spårväg. I takt med den befolkningsökning som förväntas i Uppsala behöver staden en kapacitetsstark kollektivtrafik som klarar av att hantera dessa nya stora flöden. En annan viktig faktor bakom valet av spårväg är de miljömässiga fördelarna, till exempel som att spårvägen ska drivas på förnyelsebar el. Minskad privatbilism är inget uttalat mål med spårvägen, men biltrafiken förväntas ändå minska som en följd av att en spårväg anses vara attraktiv och får en hög medelhastighet i samband med den höga prioritering som spårvägen ska erhålla. Finansieringen anses vara en av de största utmaningar med att få spårvägen realiserad.

  • 252420.
    Öling, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Industrial Engineering & Management.
    Val av teknik för hastighetsmätning i kallvalsverk2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    An often encountered problem when implementing a mass flow regulator in a rolling mill is the one with measurement of speed. The most widely used solution is to fit a pulse counter to a wheel that is in contact with the strip. Common problems with this design are for instance scratch marks on the strip and problems with the flatness measuring system.  One way of circumventing the aforementioned problems would be a non-contact measuring system. The market of today only offers systems based on the Doppler principle.

    This report evaluates three different systems for non-contact speed measurement. Important areas in the evaluation have been the ability to operate under normal rolling conditions, integration in existing control system and how well the sensor can be fitted to the rolling mill. The potential gains and possibilities for improvements have also been evaluated. 

    To be able to calculate the possible earning potential of the implementation of a mass flow regulator it’s very important to know how much scrap the rolling mill in question generates. The approximation showed that the average loss is 250 kg per coil which equals 2,5 % of the weight of a full size coil. It’s possible to improve this number with a perfectly tuned mass flow regulator. Focus for the near future ought to be on designing a solution for measuring speed with existing components with a Laser-Doppler system as a backup plan.

  • 252421.
    Ölund, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences.
    Electrical Surge Protection at Hydropower Plants2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Hydropower plants contains a lot of vital electrical power technology such as generators and transformers. To prevent damage to this equipment due to overvoltage, they are often protected by surge arrester and in some cases also by surge capacitors. The design and dimension of these components vary between different sites and regions and are often done using a template without considering the actual conditions of the site.

    In this thesis Simulink and Simscape Power System are used to study the case when a hydropower station is exposed to overvoltage. One of Fortum’s hydropower stations is simulated when being exposed to lightning and switching overvoltage to see how the existing overvoltage protection handles this stress.

    The results show that the surge arresters mounted in front of the generator managed to keep it safe for all overvoltage scenarios it is exposed to. They also shows that the surge capacitors mounted in front of the generator reduces the gradient of the overvoltage surge. However, as the surge arresters already keeps the overvoltage at safe levels, there is no need of reducing the overvoltage gradient and the surge capacitors becomes excessive in this particular hydropower plant.

  • 252422.
    Ölund, Simon
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences.
    Währborg, Cindra
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Public Health and Caring Sciences.
    Sexual risk behavior and attitudes towards condom-use amongst university students in Bangkok, Thailand: A quantitative study2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Introduction: One of the largest threats towards normal reproduction and sexual health is sexual transmitted diseases, were the most known is HIV and AIDS. The epidemiology of Thailand shows that over the last two decades several surveys reports an increase in the young adults' STD prevalence. The infections are mostly gained as a result of sexual risk behaviors and inconsistent condom use.

    AIM: The aim was to investigate sexual risk behavior and attitudes to condom use among Thailand university students in Bangkok.

    Method: The design used in this study was a descriptive cross-sectional quantitative method. A single five part questionnaire was handed out to 300 students within two different universities in Bangkok, Thailand. 269 participants completed the questionnaire and 132 of them met the inclusion criteria.

    Result: 132 participants reported having had sexual intercourse. 15 (11.4%) had a low risk behavior, 97 (73.5%) had an average risk behavior and 20 (15.2%) had a high risk behavior. There were no significant difference between male (n=97) and female (n=35) participants regarding sexual risk behavior (p= 0,68) and their attitudes towards condom-use (p= 0.990). A correlation between the two variables high sexual risk behavior and negative attitudes towards condom-use could be seen, r=0.326, n= 132, p= 0.00.

    Conclusions: The majority of the university students in our study showed an average risk behavior. The attitudes towards condoms were mostly positive with the exceptions of some specific questions. Further studies about Thai university students regarding sexual health is of importance to further decrease the sexual risks and STDs in the population.

  • 252423.
    Öman, Anders
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health.
    Hansson, Tony
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Research group (Dept. of women´s and children´s health), Paediatric Inflammation Research.
    Carlsson, Martin
    Hudiksvall Hosp, Dept Pediat, Hudiksvall, Sweden.
    Berntson, Lillemor
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, Research group (Dept. of women´s and children´s health), Paediatric Inflammation Research.
    Evaluation of screening for coeliac disease in children with juvenile idiopathic arthritis2019In: Acta Paediatrica, ISSN 0803-5253, E-ISSN 1651-2227, Vol. 108, no 4, p. 688-693Article in journal (Refereed)
    Abstract [en]

    Aim: To study the prevalence of coeliac disease (CD) in children with Juvenile idiopathic arthritis (JIA), by screening a population-based cohort of children with JIA using autoantibodies against tissue transglutaminase (anti-TG2).

    Methods: All children diagnosed with JIA in three Swedish counties, with disease onset between 2007 and 2014, were included prospectively. Serum levels of IgA anti-TG2 antibodies, IgG anti-TG2 antibodies, and total IgA were analysed. Children with positive levels of IgA anti-TG2 antibodies and children with IgA deficiency in combination with positive levels of IgG anti-TG2 antibodies were referred to the paediatric gastroenterology unit for gastroscopy and small intestine biopsy.

    Results: A total of 216 children were included, and analysis of IgA and IgG anti-TG2 antibodies was performed in 213 children. Three children were diagnosed with CD prior to the diagnosis of JIA, and three additional children were found through screening, resulting in a CD point prevalence of 2.8% (95% CI 0.6-5.0%).

    Conclusion: We found a point prevalence of CD close to previous described prevalence in the general population of Swedish children. Therefore, general screening for CD in children with JIA is not supported by our data. However, this study shows that asymptomatic CD in children with JIA may be found by screening.

  • 252424.
    Öman, Ida
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Law, Department of Law.
    Mannens talerätt vid positiv faderskapstalan – en mänsklig rättighet?2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 252425.
    Öman, Karin
    Uppsala University, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Faculty of Arts, Department of Cultural Anthropology and Ethnology.
    Alfred Nobels Björkborn1995In: Karlskoga Bergslag 1995(36), Karlskoga Bergslags Hembygdsförening, Karlskoga , 1995, no 36, p. 104-131Chapter in book (Other scientific)
  • 252426.
    Öman, Karin
    Uppsala University, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Faculty of Arts, Department of Cultural Anthropology and Ethnology, Ethnology.
    Att stå på gången och gå fram: En studie av svensk konfirmationssed1982Independent thesis Basic level (degree of Bachelor)Student thesis
  • 252427.
    Öman, Karin
    Uppsala University, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Faculty of Arts, Department of Cultural Anthropology and Ethnology.
    Ett hundraårsminne: dödsbudet från San Remo1996In: Karlskoga Bergslag 1996, Karlskoga Bergslags Hembygdsförening, Karlskoga , 1996, no 37, p. 121-123Chapter in book (Other scientific)
  • 252428.
    Öman, Karin
    Uppsala University, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Faculty of Arts, Department of Cultural Anthropology and Ethnology.
    Hembygdsarkivet - en komplex företeelse1999In: Vägen till arkivet. NNF Publications, NNF Folkloristik Åbo Akademi , 1999, Vol. 4, p. 133-165Chapter in book (Other scientific)
  • 252429.
    Öman, Karin
    Uppsala University, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Faculty of Arts, Department of Cultural Anthropology and Ethnology.
    Karlskogabilder från förra seklet1997In: Karlskoga Bergslag 1997, Karlskoga Bergslags Hembygdsförening, Karlskoga , 1997, no 38, p. 46-61Chapter in book (Other scientific)
  • 252430.
    Öman, Karin
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of Cultural Anthropology and Ethnology.
    Kolbottnar, bönemöten och krut: En etnologisk studie av Karlskoga : identitet och image : [an ethnological study of Karlskoga] : [identity and image]1998Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This dissertation aims at analysing how local history has been built up of variouselements in the past and how it is exploited. The exploitation may cause a tensionbetween different interests in society and may contribute to a change of identitiesand images. Certain people, in the study called visualizers, perceived and drewattention to places in the surroundings which had been important in one way oranother. People close to the visualizers, the like-minded, saw the value of theseplaces and helped to build the culture milieus, sites of a special social and culturalinterest, today's tourist attractions. The `designers' were people representing thegreat popular movements. The formative periods of five sites eventually appearedto contribute to an all-embracing formative period of the whole community.

    In the course of my studies of tourist brochures, newspapers, interviews andbooks on local history, and from participation in social life in Karlskoga for manyyears, a change of identities and images became apparent to me. The old image ofa place designed for iron founding gradually changed into an image of hightechnology - `Alfred Nobel's town'. This is an image which is not yet accepted byall. The identity which was formerly connected with the ironworks, changed intoseveral identities, associated with age, class, geographical district and ideology.Today, there is no common identity among people in Karlskoga. Instead, there aremany, changing in step with Time itself, as in many other places in Sweden,

  • 252431.
    Öman, Karin
    Uppsala University, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Faculty of Arts, Department of Cultural Anthropology and Ethnology.
    Nytecknat. Karlskogabornas syn på Karlskoga1998In: Karlskoga Bergslag 1998, Karlskoga Bergslags Hembygdsförening, Karlskoga , 1998, no 39, p. 104-113Chapter in book (Other scientific)
  • 252432.
    Öman, Karin
    Uppsala University, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Faculty of Arts, Department of Cultural Anthropology and Ethnology.
    År att minnas1996In: Karlskoga Bergslag 1996, Karlskoga Bergslags Hembygdsförening, Karlsgkoa , 1996, no 37, p. 124-130Chapter in book (Other scientific)
  • 252433.
    Öman, Kristina
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of Cultural Anthropology and Ethnology.
    "Jag undrar så, hur Du har det.": om insändare till sjömän i Ute och Hemma 1940-19472017Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [sv]

    I denna uppsats studeras och diskuteras 474 insändare i tidningen Ute och Hemma, skrivna till sjömän av deras anhöriga under andra världskriget. Insändarna är ett intressant exempel på ett offentligt forum, där textförfattarna var tvungen att förhålla sig till en större läsarskara än bara den direkta adressaten, men utgör också ett material ur vilket man kan teckna en bild av Sverige under perioden. Värdet i den situationsbaserade gemenskapen löper som en röd tråd genom insändarnas berättelser, värdet i kamratskapet på havet framgår lika tydligt som solidariteten inom de hemmavarandes sociala nätverk. De hemmavarandes relation till tid diskuteras också, i insändarna görs den till någonting materiellt, ett objekt att konkret förhålla sig till. Fotografiets materialitet framstår också som en värdefull resurs för de hemmavarande som bland annat ser det som en ställföreträdare för den utreste sjömannen och genom dess autenticitet manifesteras familjeenheten med hjälp av fotografiet. Även könsreglerade skillnader, såsom synen på kvinnans respektive mannens arbete samt väntan, synliggörs i insändarna. Kvinnans ansträngningar kategoriseras inte som arbete i texterna, samtidigt som mannens väntan inte diskuteras eller syns på samma sätt som kvinnans. Slutligen diskuteras krigets närvaro i insändarna, då med ordet ”krig” som exempel. Ordet förekommer inte förrän krigets slut varför det tycks vara ett slags språkligt tabu trots att konsekvenser av det – torpederingar, ransoneringar och insändarna i sig själva – är en ständigt närvarande och omtalad faktor i texterna. Insändarna blev därför en kanal för de hemmavarande genom vilken de kunde övervinna den rumsliga distansen och återknyta familjen och visar sig samtidigt vara ett givande källmaterial för historiska studier då det återger de hemmavarandes röster och berättelser från ett förstahandsperspektiv.

  • 252434.
    Öman, Kristina
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of Cultural Anthropology and Ethnology.
    "Om Du kan, så sänd oss ett livstecken!": om insändarna i Ute och Hemma under andra världskriget2014Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Med uppsatsen ämnade jag diskutera och synliggöra de normer, värden och gemenskaper som lyfts fram i de insändare som publicerades i Ute och Hemma, en tidning utgiven av Svenska kyrkans sjömansvårdsstyrelse, under andra världskriget. 141 insändare, skrivna av anhöriga till elva sjömän som var utresta under krigsåren, har studerats och diskuterats. Materialet och undersökningen visar upp olika perspektiv av väntan, till exempel hur familjen är ofullständig medan den utreste är borta, men också väntan som en liminal fas. Även tabun och vad man säger respektive inte säger diskuterades i uppsatsen, man ser bland annat en ovilja att använda ordet ”krig” samt yviga känslouttryck i insändarna medan uppmaningar om gott mod visar på tidens värdering av postitivt tänkande. Slutligen avhandlades även hur olika tillhörigheter har visat sig genom texten, där man till exempel kan se att man använder interna detaljer för att manifestera gemenskaper, samt att man inte uttrycker patriotism eller liknande uttryck för nationsbaserad tillhörighet. Istället uttrycks en mer situationsbaserad gemenskap i materialet.

  • 252435.
    Öman, Ulla
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts.
    Porträttfotografen: en etnologisk studie av en fotograf, hans ateljé och bilder1983Doctoral thesis, monograph (Other academic)
    Abstract [sv]

    Behandlar Arne Johansson och Ateljé J:son.

  • 252436. Önder, Ali Sina
    On Inflation Tax Competition2008Conference proceedings (editor) (Other academic)
  • 252437. Önder, Ali Sina
    Optimum Monetary Policy During Monetary Union Enlargement2008In: Quantitative Economic Policy, Springer , 2008Chapter in book (Other academic)
  • 252438.
    Önder, Ali Sina
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Economics, Uppsala Center for Fiscal Studies.
    Portmann, Marco
    University of Fribourg.
    Stadelmann, David
    University of Bayreuth and CREMA..
    No Place like Home: Opinion Formation with Homophily and Implications for Policy Decisions2015Report (Other academic)
    Abstract [en]

    We demonstrate a simple model of opinion diffusion where a local opinion leader acts as the initiator of public discussion. We show the possibility of driving a significant wedge between opinions of two groups that exhibit homophily even though individuals are highly conformist. In particular, we show that there exists an opinion gap between the group which the opinion leader belongs to (referred to as the residence community) and the other group; and this opinion gap is increasing in the relative size of the residence community. Using a unique dataset of national referenda in Switzerland from 2008 to 2012, we show that members of parliament (MPs) match referenda outcomes in their residence communities closer than they do in neighboring communities, and this wedge interacts signicantly with the relative size of the residence community, thus aligning with our theoretical conjectures. We conclude that observed opinion gaps can actually be overrated to the extent that they are driven by structures that underlie the social web of different groups within the society.

  • 252439.
    Önehag, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Solar Type Stars as Calibrators: A Photometric and Spectroscopic Study on the Atmospheric Properties of Late-type Stars2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Detailed knowledge of solar-type stars is essential in the understanding of the evolutionary past, presence and future of the Sun as well as the formation of its planetary system. Moreover, solar-type stars are of key significance for the study of the evolution of the Galaxy. The ages of solar-type stars map the full galactic evolution. Their surface layers are well mixed and just little affected by the interior nuclear processes. They may therefore be used as samples of the gas from which the stars were once formed.

    Models of stellar atmospheres are used to derive fundamental stellar quantities such as chemical composition, effective temperature, surface gravity, age and rotation. It is therefore also important to investigate the progress and shortcomings of the atmospheric models and the reliability of calibrations based upon these. In this thesis we explore the potential of synthetic uvbyHβ colours for deriving atmospheric parameters. The theoretical colours are derived using high-resolution synthetic spectra based on 1D atmosphere models of late-type stars. Furthermore, possible applications of the established synthetic colours on globular stellar clusters are tested.

    Observations of solar-type stars have demonstrated the existence of stars very similar to the Sun, so-called solar twins. A detailed chemical analysis of these stars, however, shows that most solar-twins are systematically richer, as compared with the Sun, in refractory elements such as Fe, Ni and Al, relative to volatile elements like C, N and O. This chemical abundance pattern has been suggested to be related to the formation of planets or the birth environment of the respective star. In this thesis we present a high-accuracy study on a solar-twin star in the old open cluster M67. We find that the star is very similar to the Sun when comparing their atmospheric parameters, effective temperature, surface gravity and metallicity. Remarkably enough, unlike most solar twins observed in the solar vicinity, the cluster twin shows the same refractory to volatile pattern as the Sun.The reason for this similarity is still unknown but further observations of the cluster will help to clarify the matter.

    M dwarfs constitute a large fraction of the detectable baryonic matter. In spite of this, detailed knowledge on the numerous neighbouring low-mass stars is still not available. The presence of strong molecular features in the spectra, and incomplete line lists for the corresponding molecules have made metallicity determinations of M dwarfs difficult. Furthermore, the faint M dwarfs require long exposure times for a signal-to-noise ratio sufficient for detailed spectroscopic abundance analysis. In this thesis we present a high resolution spectroscopic study of early-type M dwarfs in the infrared. The lack of prominent molecular bands in parts of the infrared J-band (1100--1400 nm) allows a precise continuum placement. Furthermore, we verify the adequacy of using the model atmospheres for abundance determination by observing a set of binary systems with a solar-type primary and an M dwarf companion. We present a reliable zero-point for the metallicity scale of early-type M dwarfs and verify the reliability of spectroscopic abundance analyses in the infrared.

    List of papers
    1. Calibration of Stromgren uvby-H beta photometry for late-type stars - a model atmosphere approach
    Open this publication in new window or tab >>Calibration of Stromgren uvby-H beta photometry for late-type stars - a model atmosphere approach
    2009 (English)In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 498, no 2, p. 527-542Article in journal (Refereed) Published
    Abstract [en]

    Context. The use of model atmospheres for deriving stellar fundamental parameters, such as T-eff, log g, and [Fe/H], will increase as we find and explore extreme stellar populations where empirical calibrations are not yet available. Moreover, calibrations for upcoming large satellite missions of new spectrophotometric indices, similar to the uvby-H beta system, will be needed. Aims. We aim to test the power of theoretical calibrations based on a new generation of MARCS models by comparisons with observational photomteric data. Methods. We calculated synthetic uvby-H beta colour indices from synthetic spectra. A sample of 367 field stars, as well as stars in globular clusters, is used for a direct comparison of the synthetic indices versus empirical data and for scrutinizing the possibilities of theoretical calibrations for temperature, metallicity, and gravity. Results. We show that the temperature sensitivity of the synthetic (b-y) colour is very close to its empirical counterpart, whereas the temperature scale based upon H beta shows a slight offset. The theoretical metallicity sensitivity of the m(1) index (and for G-type stars its combination with c(1)) is somewhat higher than the empirical one, based upon spectroscopic determinations. The gravity sensitivity of the synthetic c(1) index shows satisfactory behaviour when compared to obervations of F stars. For stars cooler than the sun, a deviation is significant in the c(1)-(b-y) diagram. The theoretical calibrations of (b-y), (v-y), and c(1) seem to work well for Pop II stars and lead to effective temperatures for globular cluster stars supporting recent claims that atomic diffusion occurs in stars near the turnoff point of NGC 6397. Conclusions. Synthetic colours of stellar atmospheres can indeed be used, in many cases, to derive reliable fundamental stellar parameters. The deviations seen when compared to observational data could be due to incomplete linelists but are possibly also due to the effects of assuming plane-parallell or spherical geometry and LTE.

    Keywords
    stars: fundamental parameters, techniques: photometric, stars: atmospheres, stars: late-type
    National Category
    Physical Sciences
    Identifiers
    urn:nbn:se:uu:diva-148692 (URN)10.1051/0004-6361/200810786 (DOI)000265868600028 ()
    Available from: 2011-03-10 Created: 2011-03-09 Last updated: 2017-12-11Bibliographically approved
    2. M67-1194, an unusually Sun-like solar twin in M67
    Open this publication in new window or tab >>M67-1194, an unusually Sun-like solar twin in M67
    Show others...
    2011 (English)In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 528, p. A85-Article in journal (Refereed) Published
    Abstract [en]

    Context. The rich open cluster M67 is known to have a chemical composition close to solar, and an age around 4Gyr. It thus offers the opportunity to check our understanding of the physics and the evolution of solar-type stars in a cluster environment. Aims. We present the first spectroscopic study at high resolution, R approximate to 50 000, of the potentially best solar twin, M67-1194, identified among solar-like stars in M67. Methods. G dwarfs in M67 (d approximate to 900 pc) are relatively faint (V approximate to 15), which makes detailed spectroscopic studies time-consuming. Based on a pre-selection of solar-twin candidates performed at medium resolution by Pasquini et al. (2008, A&A, 489, 677), we explore the chemical-abundance similarities and differences between M67-1194 and the Sun, using VLT/FLAMES-UVES. Working with a solar twin in the framework of a differential analysis, we minimize systematic model errors in the abundance analysis compared to previous studies which utilized more evolved stars to determine the metallicity of M67. The differential approach yields precise and accurate chemical abundances for M67, which enhances the possibility to use this object in studies of the potential peculiarity, or normality, of the Sun. Results. We find M67-1194 to have stellar parameters indistinguishable from the solar values, with the exception of the overall metallicity which is slightly super-solar ([Fe/H] = 0.023 +/- 0.015). An age determination based on evolutionary tracks yields 4.2 +/- 1.6Gyr. Most surprisingly, we find the chemical abundance pattern to closely resemble the solar one, in contrast to most known solar twins in the solar neighbourhood. Conclusions. We confirm the solar-twin nature of M67-1194, the first solar twin known to belong to a stellar association. This fact allows us to put some constraints on the physical reasons for the seemingly systematic departure of M67-1194 and the Sun from most known solar twins regarding chemical composition. We find that radiative dust cleansing by nearby luminous stars may be the explanation for the peculiar composition of both the Sun and M67-1194, but alternative explanations are also possible. The chemical similarity between the Sun and M67-1194 also suggests that the Sun once formed in a cluster like M67.

    Keywords
    stars: abundances, stars: fundamental parameters, stars: solar-type, Sun: abundances, open cluster and associations: individual: NGC 2682 (M67), techniques: spectroscopic
    National Category
    Physical Sciences
    Identifiers
    urn:nbn:se:uu:diva-151907 (URN)10.1051/0004-6361/201015138 (DOI)000288541600117 ()
    Available from: 2011-04-19 Created: 2011-04-19 Last updated: 2017-12-11Bibliographically approved
    3. M-dwarf metallicities: A high-resolution spectroscopic study in the near infrared
    Open this publication in new window or tab >>M-dwarf metallicities: A high-resolution spectroscopic study in the near infrared
    Show others...
    2012 (English)In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 542, p. A33-Article in journal (Refereed) Published
    Abstract [en]

    The relativley large spread in the derived metallicities ([Fe/H]) of M dwarfs shows that various approaches have not yet converged to consistency. The presence of strong molecular features, and incomplete line lists for the corresponding molecules have made metallicity determinations of M dwarfs diffcult. Furthermore, the faint M dwarfs require long exposure times for a signal-to-noise ratio suffcient for a detailed spectroscopic abundance analysis.

    We present a high-resolution (R~50,000) spectroscopic study of a sample of eight single M dwarfs and three wide-binary systems observed in the infrared J-band.

    The absence of large molecular contributions allow for a precise continuum placement. We derive metallicities based on the best fit synthetic spectra to the observed spectra. To verify the accuracy of the applied atmospheric models and test our synthetic spectrum approach, three binary systems with a K dwarf primary and an M dwarf companion were observed and analysed along with the single M dwarfs.

    We obtain a good agreement between the metallicities derived for the primaries and secondaries of our test binaries and thereby confirm the reliability of our method of analysing M dwarfs. Our metallicities agree well with certain earlier determinations, and deviate from others.

    We conclude that spectroscopic abundance analysis in the J band is a reliable method for establishing the metallicity scale for M dwarfs. We recommend its application to a larger sample covering lower as well as higher metallicities. Further prospectsof the method include abundance determinations for individual elements.

    Keywords
    stars: atmospheres, stars: binaries visual, stars: low-mass, stars: abundances, techniques: spectroscopic
    National Category
    Astronomy, Astrophysics and Cosmology
    Research subject
    Astronomy
    Identifiers
    urn:nbn:se:uu:diva-158847 (URN)10.1051/0004-6361/201118101 (DOI)000305803300025 ()
    Available from: 2011-09-18 Created: 2011-09-18 Last updated: 2017-12-08Bibliographically approved
  • 252440.
    Önehag, Anna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Gustafsson, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Eriksson, K.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Edvardsson, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Calibration of Stromgren uvby-H beta photometry for late-type stars - a model atmosphere approach2009In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 498, no 2, p. 527-542Article in journal (Refereed)
    Abstract [en]

    Context. The use of model atmospheres for deriving stellar fundamental parameters, such as T-eff, log g, and [Fe/H], will increase as we find and explore extreme stellar populations where empirical calibrations are not yet available. Moreover, calibrations for upcoming large satellite missions of new spectrophotometric indices, similar to the uvby-H beta system, will be needed. Aims. We aim to test the power of theoretical calibrations based on a new generation of MARCS models by comparisons with observational photomteric data. Methods. We calculated synthetic uvby-H beta colour indices from synthetic spectra. A sample of 367 field stars, as well as stars in globular clusters, is used for a direct comparison of the synthetic indices versus empirical data and for scrutinizing the possibilities of theoretical calibrations for temperature, metallicity, and gravity. Results. We show that the temperature sensitivity of the synthetic (b-y) colour is very close to its empirical counterpart, whereas the temperature scale based upon H beta shows a slight offset. The theoretical metallicity sensitivity of the m(1) index (and for G-type stars its combination with c(1)) is somewhat higher than the empirical one, based upon spectroscopic determinations. The gravity sensitivity of the synthetic c(1) index shows satisfactory behaviour when compared to obervations of F stars. For stars cooler than the sun, a deviation is significant in the c(1)-(b-y) diagram. The theoretical calibrations of (b-y), (v-y), and c(1) seem to work well for Pop II stars and lead to effective temperatures for globular cluster stars supporting recent claims that atomic diffusion occurs in stars near the turnoff point of NGC 6397. Conclusions. Synthetic colours of stellar atmospheres can indeed be used, in many cases, to derive reliable fundamental stellar parameters. The deviations seen when compared to observational data could be due to incomplete linelists but are possibly also due to the effects of assuming plane-parallell or spherical geometry and LTE.

  • 252441.
    Önehag, Anna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Gustafsson, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Korn, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Abundances and possible diffusion of elements in M67 stars2014In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 562, p. A102-Article in journal (Refereed)
    Abstract [en]

    Context. The rich open cluster M67 is known to have a chemical composition close to solar and an age of about 3.5-4.8 Gyr. It offers an important opportunity to check and develop our understanding of the physics and the evolution of solar-type stars. Aims. We present a spectroscopic study at high resolution, R approximate to 50 000, of 14 stars located on the main sequence, at the turn-off point, and on the early subgiant branch in the cluster in order to investigate its detailed chemical composition, for comparison with the Sun and solar twins in the solar neighbourhood, and to explore selective atomic diffusion of chemical elements as predicted by stellar-structure theory. Methods. We have obtained VLT/FLAMES-UVES spectra and analysed these strictly differentially in order to explore chemical-abundance similarities and differences between the M67 stars and the Sun and among the M67 stars themselves. Results. Individual abundances of 19 different chemical elements are obtained for the stars. They are found to agree very well with solar abundances, with abundance ratios closer to solar than those of most solar twins in the solar neighbourhood. An exception is Li, which shows considerable scatter among the cluster stars. There is a tendency for the cluster-star abundances to be more depleted than the abundances in the field stars in correlation with the condensation temperature of the elements, a tendency also found earlier for the Sun. Moreover, the heavy-element abundances are found to be reduced in the hotter stars and dwarfs by typically <= 0.05 dex, as compared to the abundances of the subgiants. Conclusions. The results support the hypothesis that the gas of the proto-cluster was depleted by formation and cleansing of dust before the stars formed. They also add support to the proposal that the Sun was formed in a dense stellar environment. Moreover, the observed minor reductions of heavy elements, relative to our standard star M67-1194 and the subgiants, in the atmospheres of dwarfs and turn-off point stars seem to suggest that diffusion processes are at work in these stars, although the evidence is not compelling. Based on theoretical models, the diffusion-corrected initial metallicity of M67 is estimated to be [Fe/H] = +0.06.

  • 252442.
    Önehag, Anna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Heiter, Ulrike
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Gustafsson, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Theoretical Astrophysics.
    Piskunov, Nikolai
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    Plez, Bertrand
    Laboratoire Univers et Particules de Montpellier, CNRS, Université.
    Reiners, Ansgar
    Universität Göttingen, Institut für Astrophysik.
    M-dwarf metallicities: A high-resolution spectroscopic study in the near infrared2012In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 542, p. A33-Article in journal (Refereed)
    Abstract [en]

    The relativley large spread in the derived metallicities ([Fe/H]) of M dwarfs shows that various approaches have not yet converged to consistency. The presence of strong molecular features, and incomplete line lists for the corresponding molecules have made metallicity determinations of M dwarfs diffcult. Furthermore, the faint M dwarfs require long exposure times for a signal-to-noise ratio suffcient for a detailed spectroscopic abundance analysis.

    We present a high-resolution (R~50,000) spectroscopic study of a sample of eight single M dwarfs and three wide-binary systems observed in the infrared J-band.

    The absence of large molecular contributions allow for a precise continuum placement. We derive metallicities based on the best fit synthetic spectra to the observed spectra. To verify the accuracy of the applied atmospheric models and test our synthetic spectrum approach, three binary systems with a K dwarf primary and an M dwarf companion were observed and analysed along with the single M dwarfs.

    We obtain a good agreement between the metallicities derived for the primaries and secondaries of our test binaries and thereby confirm the reliability of our method of analysing M dwarfs. Our metallicities agree well with certain earlier determinations, and deviate from others.

    We conclude that spectroscopic abundance analysis in the J band is a reliable method for establishing the metallicity scale for M dwarfs. We recommend its application to a larger sample covering lower as well as higher metallicities. Further prospectsof the method include abundance determinations for individual elements.

  • 252443.
    Önehag, Anna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Theoretical Astrophysics.
    Korn, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Theoretical Astrophysics.
    Gustafsson, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Theoretical Astrophysics.
    Stempels, Eric
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Observational Astronomy.
    VandenBerg, D. A.
    M67-1194, an unusually Sun-like solar twin in M672011In: Astronomy and Astrophysics, ISSN 0004-6361, E-ISSN 1432-0746, Vol. 528, p. A85-Article in journal (Refereed)
    Abstract [en]

    Context. The rich open cluster M67 is known to have a chemical composition close to solar, and an age around 4Gyr. It thus offers the opportunity to check our understanding of the physics and the evolution of solar-type stars in a cluster environment. Aims. We present the first spectroscopic study at high resolution, R approximate to 50 000, of the potentially best solar twin, M67-1194, identified among solar-like stars in M67. Methods. G dwarfs in M67 (d approximate to 900 pc) are relatively faint (V approximate to 15), which makes detailed spectroscopic studies time-consuming. Based on a pre-selection of solar-twin candidates performed at medium resolution by Pasquini et al. (2008, A&A, 489, 677), we explore the chemical-abundance similarities and differences between M67-1194 and the Sun, using VLT/FLAMES-UVES. Working with a solar twin in the framework of a differential analysis, we minimize systematic model errors in the abundance analysis compared to previous studies which utilized more evolved stars to determine the metallicity of M67. The differential approach yields precise and accurate chemical abundances for M67, which enhances the possibility to use this object in studies of the potential peculiarity, or normality, of the Sun. Results. We find M67-1194 to have stellar parameters indistinguishable from the solar values, with the exception of the overall metallicity which is slightly super-solar ([Fe/H] = 0.023 +/- 0.015). An age determination based on evolutionary tracks yields 4.2 +/- 1.6Gyr. Most surprisingly, we find the chemical abundance pattern to closely resemble the solar one, in contrast to most known solar twins in the solar neighbourhood. Conclusions. We confirm the solar-twin nature of M67-1194, the first solar twin known to belong to a stellar association. This fact allows us to put some constraints on the physical reasons for the seemingly systematic departure of M67-1194 and the Sun from most known solar twins regarding chemical composition. We find that radiative dust cleansing by nearby luminous stars may be the explanation for the peculiar composition of both the Sun and M67-1194, but alternative explanations are also possible. The chemical similarity between the Sun and M67-1194 also suggests that the Sun once formed in a cluster like M67.

  • 252444.
    Önell, A
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Mathematics and Computer Science, Department of Information Technology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Mathematics and Computer Science, Department of Information Technology, Automatic control. AUTOMATIC CONTROL.
    Söderström, T
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Mathematics and Computer Science, Department of Information Technology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Mathematics and Computer Science, Department of Information Technology, Automatic control. AUTOMATIC CONTROL.
    Halvorsen, K
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Mathematics and Computer Science, Department of Information Technology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Mathematics and Computer Science, Department of Information Technology, Automatic control. AUTOMATIC CONTROL.
    Lanshammar, H
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Mathematics and Computer Science, Department of Information Technology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Mathematics and Computer Science, Department of Information Technology, Automatic control. AUTOMATIC CONTROL.
    Identifiering av människokroppens balanssystem2000In: Reglermöte 2000 (National Conference on Control), 2000Conference paper (Refereed)
  • 252445.
    Önell, Annica
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Systems and Control. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Automatic control.
    Quantifying human balance: Analysis of force plate data1999Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    There is a lack of reliable methods for assessment of balance suited for routine use in clinical settings. The thesis focuses on analysis of force plate data for evaluation of balance during normal, unperturbed standing and sitting. Some commonly used force plate based methods during unperturbed standing are presented.

    Traditional measures, which have been used to quantify the postural sway during standing, were applied to seated children with and without spina bifida. Fundamental differences, that can not be observed visually, were found between the groups. However, the reliability on an individual level was limited since the method could not be used to distinguish between subjects from the two groups.

    It is not only of interest to measure how much the subject sways, but also what movement strategy the subject uses, that is, how he or she sways. A method for analysis of the movement strategy in the sagittal plane during standing is presented and tested. The subject's movements are compared to the movements of an inverted pendulum model. For movement analysis a kinematic measurement system is usually required, while the inverted pendulum method only needs force plate data for the analysis.

    To investigate the relationship between different force plate measures the measures were a) compared to each other and b) compared to a clinical balance test. Results on stroke patients showed that many of the measures quantify different aspects of standing. The standard deviation of the vertical ground reaction force was the only measure that was significantly correlated to the clinical balance test. Measurements on healthy adults and three groups of subjects with reduced or not fully developed balance were analysed to investigate the vertical force further. The healthy adults damped the vertical bodyoscillations caused by the heartbeats more efficiently than the other three groups.

    Finally, it was investigated under what conditions system identification can be used to model the balance system. In contrast to previous studies the model parameters were successfully estimated without any external perturbations and without a kinematic measurement system.

  • 252446.
    Önnerud, Hans
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Technology, Department of Engineering Sciences. ION PHYSIC.
    Palmblad, Magnus
    Gellerstedt, Göran
    Investigation of lignin oligomers using electrospray ionisation mass spectrometry2003In: Holzforschung, no 57, p. 37-43Article in journal (Refereed)
  • 252447.
    Önnerud, Per
    Uppsala University, Disciplinary Domain of Science and Technology.
    The influence of chemical environment on magnetic structure in the (Fe1-xCox)2As and Pd3Mn-D systems 1995Doctoral thesis, comprehensive summary (Other academic)
  • 252448.
    Önneslöv, Gustav
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Tigerström, Alexander
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Internationella leverantörsrelationer: En kvalitativ undersökning av Uppsalas bioteknologiska sektor2008Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis investigates what kind of relations small businesses have with their international suppliers. We want to find out if these are of the close embedded kind or if these relations are at arms length. In the cases we find close relations we also look at what kind of relation it is. This thesis looks at three small biotechnology companies in Uppsala. We find that these companies have a mix of different relations with their suppliers. Among those are embedded relations of social and business type.

  • 252449.
    Önneslöv, Gustav
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Tigerström, Alexander
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Rudström, David
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Business Studies.
    Projektstyrningsmodeller i praktiken: En fallstudie på spelföretaget Starbreeze i Uppsala2009Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna uppsats undersöker hur projektstyrningsmodellerna Stage-Gate och Scrum i praktikenpåverkar möjligheten till framgångsrika mjukvaruutvecklingsprojekt. För att undersöka dettahar två projekt vid företaget Starbreeze i Uppsala analyserats. I uppsatsen presenteras elvafaktorer för framgångsrika mjukvaruutvecklingsprojekt. Stage-Gate och Scrum påverkarsamtliga av dessa elva faktorer positivt och därmed ökas möjligheten till framgång i projektet.Analysen visar på att det är viktigt att modellerna används till sin helhet och inte bara till vissdel. Det första av de två projekten använde endast delar av Stage-Gate och Scrum och led somen anledning av detta av problem under utvecklingen. Till det efterföljande projektet hadeanvändningen av projektstyrningsmodellerna utvecklats och detta projekt var merframgångsrikt.

  • 252450. Önskog, Jenny
    et al.
    Freyhult, Eva
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences.
    Landfors, Mattias
    Ryden, Patrik
    Hvidsten, Torgeir R.
    Classification of microarrays: synergistic effects between normalization, gene selection and machine learning2011In: BMC Bioinformatics, ISSN 1471-2105, E-ISSN 1471-2105, Vol. 12, p. 390-Article in journal (Refereed)
    Abstract [en]

    Background: Machine learning is a powerful approach for describing and predicting classes in microarray data. Although several comparative studies have investigated the relative performance of various machine learning methods, these often do not account for the fact that performance (e. g. error rate) is a result of a series of analysis steps of which the most important are data normalization, gene selection and machine learning. Results: In this study, we used seven previously published cancer-related microarray data sets to compare the effects on classification performance of five normalization methods, three gene selection methods with 21 different numbers of selected genes and eight machine learning methods. Performance in term of error rate was rigorously estimated by repeatedly employing a double cross validation approach. Since performance varies greatly between data sets, we devised an analysis method that first compares methods within individual data sets and then visualizes the comparisons across data sets. We discovered both well performing individual methods and synergies between different methods. Conclusion: Support Vector Machines with a radial basis kernel, linear kernel or polynomial kernel of degree 2 all performed consistently well across data sets. We show that there is a synergistic relationship between these methods and gene selection based on the T-test and the selection of a relatively high number of genes. Also, we find that these methods benefit significantly from using normalized data, although it is hard to draw general conclusions about the relative performance of different normalization procedures.

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