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  • 251.
    Jonasson, Josefin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Biophysical characterization of the interactions involving the nuclear coactivator domain of the CREB binding protein2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 252.
    Jonasson, Kristoffer
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Biokemisk och immunologisk karaktärisering av pepsin-spjälkade mjölkallergener2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Milk allergens were digested by allowing them to flow through a chromatography column, where pepsin was conjugated to the stationary phase of the column. The allergen fragments were then characterized both biochemically, by using SDS-PAGE and gel permeation chromatography, and immunologically, by examining their reactivity to IgE and monoclonal antibodies.

  • 253.
    Jones, William
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Malaria infected male collared flycatchers, Ficedula albicollis experience higher reproductive success and tend to have larger sexual ornaments2016Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    How parasites influence the population dynamics of their hosts depends on 1) theproportion of individuals that carry the infection in the population, 2) what type of individuals aremost susceptible to infection and 3) the fitness effects of infection. In this study I first investigate thefrequency of malaria strains transmitted in the African winter quarters or at the European breedinggrounds in collared flycatchers (Ficedula albicollis). I then zoom in on the relationship between avianmalaria infection status and condition, expression of sexually selected ornament and reproductiveperformance of male collared flycatchers. I found that female flycatchers are more likely to beinfected than males and that both sexes have a large bias towards infection with European strains ofmalaria. Infected male flycatchers have higher reproductive success and tend to have largerornaments but there was no detected relationship between malaria infection and male condition.This is the first example, that I am aware of, of a positive relationship between malaria infection andreproductive success.

  • 254.
    Jonsäll, Linnea
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Mutational analysis of the csgD mRNA leader: search for a mode of regulation2013Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The CsgD protein is the master regulator of a pathway leading to the formation of curli, in essence regulating the switch between a motile and a sessile lifestyle for bacteria. The 5’-UTR region of the csgD mRNA is a hotspot for multiple regulatory small RNAs (sRNA) involved in a complex regulatory network. Even though it is previously known how the interaction takes place it is unknown how sRNA binding affects the translational activity. In order to suggest a mode of regulation a mutational assay was performed by making changes in the csgD 5’-UTR and investigate what the translational effects were. Mutations in different regions are shown to affect the translation levels in various ways.

  • 255.
    Josefsson, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    The Many Phases of Phenology: Geographic and Inter-Specific Differences in Phenological Between-Year Variation2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As climate-driven changes in phenology are becoming more apparent, the need to quantify these changes is increasing. An important challenge in detecting phenological changes is that between-year variation in phenology is large. Between-year variation determines the statistical power of comparisons between contemporary and historical observations. For 44 plant species with different distributions across Sweden, geographicand inter-specific differences in between-year variation in different phenophases (budburst, flowering, ripe fruits, and leaf fall) was studied. I also modeled and evaluated theresponse of bud burst, and flowering, to temperature using three different temperature sum models over a latitudinal gradient. The data used was a sub-sample from a dataset collected by a Swedish nation-wide phenology network between 1873-1917. In agreement with previous studies, I show that early spring phases have a higher variability than phases occurring later in the season. However, the relation between onset and variation was not monotonically decreasing. In the geographical analyses, a unimodal relation between between-year variation and latitude was found, that is, the between-year variation decreased along the latitudinal gradient for early- and late season events, while it increased over latitude for summer events. These patterns are, to a great extent, reflections of patterns in air temperatures which is discussed using meteorological data from adjacent climate stations. Models were evaluated using Akaike's Information Criterion, and in 60% of all fits, the Spring warming CF2 model (SWCF2; the model with the least number of parameters) was selected as the best model to describe the data. For Sorbus aucuparia bud burst, in the two parameter model SWCF2, both parameters (threshold temperature andtemperature sum) correlated with latitude. However, future analysis using more locations and a wider span of species will be needed to understand the generality in these findings. In conclusion, future efforts to detect and quantify phenological changes need to consider differences in between-year phenological variability along geographical gradients and among species with different phenology.

  • 256.
    Julin, Madeleine
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organism Biology, Systematic Biology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Tar production – traditional medicine and potential threat to biodiversity in the Marrakesh region: An ethnobotanical study2008Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 257.
    Jönsson, Jennifer
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Development of immunoassay for C-reactive protein with chronoamperometric detection2016Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 258.
    Kaira, Mustapha
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    In situ molecular profilling of the microenvironment of breast carcinoma2015Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    High stromal PDGF receptor B expression was shown to have strong prognostic value in a studyinvolving over 600 breast cancer patients however, the molecular role of the receptor in tumordevelopment remains unclear. In this project we studied the spatial distribution and expressionlevels of a panel genes and markers associated with PDGF signaling, in breast cancer tumormicroenvironment (TME) using a newly developed technique -in situ sequencing. The techniquerelies on padlock probes which we validated with corresponding RNA sequencing, microarray,and immunohistochemistry data. Our results showed that high PDGF receptor B mRNA colocalizedwith markers of two pathways, TGFβ and Hedgehog signaling; this suggests that theymight contribute to the PDGF-receptor B-driven tumor growth. We also showed that stromalPDGF signaling is stimulated predominantly by tumor cells. Finally, further expression profilingof each individual gene revealed that CXCL14 was mainly expressed in the stroma, ACTA2expression was enriched in the tumor/stroma boundary while the stem-cell marker, OCT3, wasexpressed in the interior of the tumor cells.

  • 259.
    Kalathil, Aravind Nambiar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    The effect of Magnetic Fields on Dictyostelium discoideum, Osteoblasts and Fibroblasts2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The effect of EM waves on cells has been a subject of growing interest for many years. In this project we tried to recreate the increased proliferation rate noticed in the Dictyostelium discoideum.

    The effect was not initially observed in the osteoblasts, since the experiments were attempted without a complete understanding of all the parameters involved that increased the proliferation rate.

    However, with the fibroblast cell, a similar trendline was achieved, with the highest difference in growth peaking at 22% using a magnetic field of 20Hz and 2300μT.

    In this project we try to explore the implications of such an effect, why it refused to work with one cell line, and why it worked with another, even though the effect was not as pronounced as it was with the amoebas. 

  • 260.
    Kallazhi, Aswathy
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Study of co-translational folding of E. coli dihydrofolate reductase using fluorescence resonance energy transfer (FRET)2018Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    In prokaryotes, protein synthesis and folding are often coupled, and the protein begins to fold from the N-terminus as it is being synthesized. It has been hypothesised that there could be kinetic coupling of the speed of translation and the folding, which means that an altered rate of synthesis can cause a possible misfolding of the protein. Testing this hypothesis will be impactful for protein misfolding diseases such as Alzheimer’s, Parkinson’s, Huntington’s etc., and also help in the study of the effect of synonymous, non-synonymous and rare codon changes on a protein. However, research works in this regard are far and few and none of them have been carried out in a homologous in vitro system.

    This project is an attempt to study the co-translational folding of Escherichia coli protein dihydro folate reductase (DHFR) using an E. coli reconstituted transcription/ translation system (RTTF) in vitro. The preparatory phase involves: preparation of UAG mutants of the DHFR DNA (for site-specific incorporation of fluorescent dyes), preparation of amber tRNAs which recognise the UAG codons, aminoacylation of the tRNAs and labelling the amino acids with fluorescent dyes. The experimental phase involves: incorporation of each of the fluorescent amino acids in the protein during in vitro synthesis in steady-state, observing incorporation of the same in stopped-flow spectrofluorimeter, attempting to observe fluorescent resonance energy transfer (FRET) between the two dyes due to co-translational folding.

    The preparatory and experimental phases were completed successfully, and it has been established that the amino acids with the fluorescent moieties can be incorporated site specifically in the mutant protein. The synthesis of the protein was observed using stopped-flow spectrometer for each of the fluorescent amino acids individually.  The synthesis of the mutants using two sets of dye pairs was also observed using a steady-state fluorimeter as well as stopped-flow spectrofluorimeter and the FRET between the two fluorophores was obtained. Although further experiments are required to fully validate and standardize this technique,  it will, even now,  aid in the study of the folding of proteins in a cell-free system. 

    The full text will be freely available from 2021-11-30 15:41
  • 261.
    Kalsoom, Faheema
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Analysis of genome-wide patterns of differentiation in the chiffchaff (Phylloscopus collybita spp.)2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Unraveling the genetic basis of reproductive isolation is significant for the understanding of the speciation process. Hybrid zones, the regions where two species co-occur and produce hybrids, offer excellent natural environments where the initiation and establishment of genetic barriers to gene flow between two incipient species can be studied. The chiffchaff species system with its natural hybrid zone is a great model system in this regard. This study aims at quantifying the genetic differentiation between European (Phylloscopus collybita abietinus) and Siberian (P. c. tristis) chiffchaff species and identifying genes of potential significance for reproductive isolation by identification of highly differentiated genomic regions between these two subspecies. A reference-assisted consensus assembly for chiffchaff was generated using collared flycatcher as the reference and then population re-sequencing analyses including calculation of population genetic summary statistics were carried out for both allopatric and sympatric samples of both subspecies. The average genetic differentiation between allopatric populations of abietinus and tristis was found to be moderate (FST = 0.220), higher than between subspecies sampled in the sympatric zone (FST = 0.107). The genetic differentiation on the Z chromosome was found to be higher (FST = 0.31) than the differentiation on the autosomes (FST = 0.21). Eight distinct peaks of divergence were detected where genomes of the subspecies were highly differentiated in a limited genetic region. These regions contained around 26 genes, of which the most interesting have functions related to sensory perception of sound, learning and pigmentation. In addition, the nucleotide diversity was also found to be lower in all those high FST peak regions than the surrounding genomic regions. High fixation index values, low nucleotide diversity and identification of genes important for reproductive isolation on the same peak of divergence indicate that these regions in the genome of chiffchaff species are, or have been, under the influence of selection. The results have implications for understanding the genetic basis of local adaptation and reproductive isolation in chiffchaff in particular and for the understanding of speciation and adaptation processes in general.

  • 262.
    Kandasamy, Dineshkumar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Study on yeast enzymes Urc1p and Urc4p in a novel uracil catabolism pathway (URC)2012Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Purine and pyrimidine bases are the central precursors of DNA and RNA and theirintracellular concentration is balanced by three pathways- de novo, salvage and catabolicpathways. Uracil catabolism pathway has been found in several bacteria and in some fungi(including yeast). Seven genes, URC1-7 have been found to be involved in this novelpathway. There are two “unknown genes” in the yeast Lachancea (Saccharomyces) kluyveri,namelyURC1 and URC4, which play a central role in this pathway and their exact functionremains a mystery.In this project, two S. kluyveri genes, URC1&URC4, were over-expressed in the bacterialsystem and successfully purified. Our preliminary functional assay showed that uridinemonophosphate (UMP) is a likely substrate for Urc1p at pH7, 25ºC. It was shown clearly thatboth uracil and uridine were not the substrate for Urc1p. We tried to phosphorylatechemically synthesized ribosylurea using Drosophila melanogaster deoxyribonucleosidekinase and compared the activity between phosphorylated and non- phosphorylated RU atdifferent conditions. Phosphorylated ribosylurea seemed to be a likely substrate for Urc4p atpH7, 37ºC.

    Keywords: Uridine monophosphate (UMP), ribosylurea (RU), uracil catabolism.

  • 263.
    Kanders, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Recombinant production and immunological characterization of major peanut allergen Ara h 22004Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 264.
    Karim, Sanaz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Applying Systems Approach to Educational-Organizational Change: Improvement of an Interdisciplinary Program, Masters in Sustainable Development2009Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    After the introduction of the term,  sustainable development, a variety of  academicians from different disciplines tried to conceptualize it in their own way, drawing on these views, many different degrees but with similar titles have been established in many universities all around the world. Masters  program in  Sustainable Development  (MSD) at Uppsala University and the Swedish University of Agricultural Sciences (SLU) is one the most recent ones. Before starting this study, it was investigated that the expectations of the different actors in this program are not fulfilled completely. Presence of many different ideas and perspectives in addition to the high number of actors involved in the situation made the situation too complex to be fixed easily. Therefore, the Soft Systems Methodology (SSM), as an appropriate approach for improving complex problematic situations,  is  used to reform the organization of  the  MSD in coming years. The process of identifying the  challenges of this program and then  improving some of them in  practice  are described in this thesis. Alongside the  action phase, the applications of Systems Approach in transformation of Education for Sustainable Development (ESD) are explored.  It is investigated that three levels of learning, i.e. basic, meta-  and epistemic learning, and accordingly three levels of organizational change, i.e. the first, second and third order, need to be recognized, if an ESD program is to be different from the unsustainable trends of education.

  • 265.
    Karlberg, Ylva
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. IceLab - Interdisciplinary Science Lab, Umeå universitet.
    Importance of fish community structure, nutrients and browning for shallow lake ecosystem dynamics: A modelling perspective2019Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    In a changing climate, it is increasingly important to be able to model environmental effects on food webs, and to do that, one must have appropriate dynamic models. I present a shallow lake ecosystem model where producers, grazers, carnivores, piscivores, and detritivores are coupled through resource (light, nutrients and detritus) fluxes between the benthic and pelagic habitats and through carnivore life history events (ontogenetic habitat and diet shifts). The two habitats each contain primary producers, grazers, carnivores and detritivores. Within the habitats, there is strong top-down regulation, but across habitat boundaries, bottom-up interactions drive production. In the absence of piscivores, stage-structured carnivores cause intriguing patters of alternative stable states. Notably, the model predicts a lesser dependence on benthic production with detritus presence. Model predictions are largely in agreement with empirical studies. The results have implications for management of freshwater, and for the interpretation of previous models.

  • 266.
    Karlsson, Erik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Temperature acclimation in dragonfly larvae: which species are more vulnerable to global warming?2017Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
  • 267.
    Karlsson, Filip
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Unfolding probes: A novel method for biomolecular detection2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Unfolding probes is a novel detection method for biomolecules, involving an oligonucleotide probe that can be amplified and which thereby gives rise to a strong signal for individual probe - target interactions. The present project focuses on a variant of unfolding probes called 2-fold probes and on optimizing the detection efficiency of synthetic targets. Furthermore, proof of concept experiments were performed for the detection of Her2 mRNA in cells.

  • 268.
    Karlsson, Hanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Hur påverkas mosippa Pulsatilla vernalis av sin omgivande miljö och har naturvårdsåtgärderna varit effektiva?2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 269.
    Karlsson, Jennie
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Pica-beteende hos katter (Felis catus): påverkan av ras och miljö?2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Pica is a behavior that can be seen in several animal groups. In cats, it means that they are eating, chewing or licking on material that is non-food. In this study the data was collected through an online survey. In total 522 responses, of which 26% of the cats were exhibiting pica. It was found that 28% of the housecats and 26% of purebred cats exhibited pica. This study examined whether race or environment could be a factor determining when cats exhibit pica, but no significance was found. There are only a few earlier studies done on the subject. This makes it important to further investigate the factors that cause pica in cats.

  • 270.
    Karlsson, Jenny
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Brink, Matilda
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Annala, Elina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Potential application areas for Fresenius Kabi's bonus products2019Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The main purpose of the project was to investigate existing markets within the food- and cosmetic industry in order to determine a strategy for market entrance with the bonus product of Fresenius Kabi. The original bonus product, P080, is a rest product from the process where phospholipids are extracted from egg yolk powder. P80 is a refine version of the P080 where egg yolk oil has been extracted, hence the protein content in P80 is higher. The extracted egg yolk oil is the final portion of the bonus product. Thereby, the original bonus product can be divided into two refined fractions. This project investigates the potential for each of these three substances to be a part of a fictive product. 

    By scanning the global protein market as well as the egg yolk protein and egg oil market, seven potential product segments were discovered. These segments were further evaluated in order to bring out specific products that were potential candidates as products based on the bonus product. 

    The analysis resulted in two fictive products based on P080; high value nutrition bars and snacks for seniors, one based on P80; protein powder, and one based on egg yolk oil; dietary supplement. All presented in three business cases.

  • 271.
    Karlsson, Joakim
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Differential and co-expression of long non-coding RNAs in abdominal aortic aneurysm2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This project concerns an exploration of the presence and interactions of long non-coding RNA transcripts in an experimental atherosclerosis mouse model with relevance for human abdominal aortic aneurysm development. 187 long noncoding RNAs, two of them entirely novel, were found to be differentially expressed between angiotensin II treated (developing abdominal aortic aneurysms) and non-treated apolipoprotein E deficient mice (not developing aneurysms) harvested after the same period of time. These transcripts were also studied with regards to co-expression network connections. Eleven previously annotated and two novel long non-coding RNAs were present in two significantly disease correlated co-expression groups that were further profiled with respect to network properties, Gene Ontology terms and MetaCore© connections. 

  • 272.
    Karlsson, Matilda
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    The relative importance of beavers (Castor fiber) and browsers on the recruitment of broad-leaved trees in riparian areas2019Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Managed forest landscapes in Sweden are dominated by boreal coniferous forest and are deficient in broad-leaved trees. Both beavers (Castor fiber) and ungulate browsers prefer broad-leaved trees to conifers, and the interaction between multiple herbivores may have a considerable impact on the recruitment of deciduous trees in riparian areas. To evaluate the relative importance of beavers and browsers on tree recruitment, I conducted an inventory of broad-leaved tree species at five beaver sites in Färnebofjärden National Park, Sweden. At each site, five transects were established perpendicular to the shoreline in the riparian zone, resulting in a grid of 35 sample plots at each beaver site. Foraging activity of both beavers and browsers (e.g. ungulates) was concentrated to a narrow band in the riparian zone and there was a decrease in the proportion of beaver-cut and browsed trees further away from the shoreline. Beavers preferred birch (Betula spp.) and grey willow (Salix cinerea) while browsers preferred oak (Quercus robur). Beavers targeted larger trees while browsers targeted seedlings <1 cm in diameter. Old-growth trees of high conservation value, such as aspen (Populus tremula) and birch, are at risk to be cut by beaver, yet long-term protection of broad-leaved stands requires a shift in focus towards strategies that enhance tree recruitment by considering and mitigating pressure from multiple herbivores.

  • 273.
    Karthikraj, Karthikraj
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Crosstalk between DNA repair and chromatin modifications2013Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
  • 274.
    Kempe, Kerstin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    The effect of flowering synchrony on reproductive success in the tundra cushion plant Silene acaulis (Carophyllaceae)2015Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
  • 275.
    Khalatbari, Leili
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Research center in biodiversity and genetic resources (CIBIO), University of Porto.
    Effect of the habitat fragmentation on the Grévy’s zebra population genetic structure2013Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    The exponential growth of the human population is limiting the wildlife habitat all around the word. In recent years habitat loss and fragmentation is one of the main reasons that threats the wild life species. The Grévy’s zebra (Equus grevyi) is the most endangered member of Zebras. Their historical range was previously from north Ethiopia to southwest Somalia and to northern Kenya. Currently they are distributed only in fragmented habitats in central and eastern part of Ethiopia and in the north of Kenya. They are listed as endangered in the IUCN red list, as their population has declined 68% in 27 years. There are very few studies on genetic structure of this species, and investigating the genetic connection between different populations is needed.

    Molecular markers are one of the best tools to understand the level of fragmentation, population bottlenecks or potential inbreeding. In this study, the population structure of Ethiopian zebra population from Alledeghi Wildlife Reserve (WR) and Sarite area was studied using non-invasively obtained fecal samples collected during 2001-2011. This study analyzes genetic variation at 10 microsatellite loci and a 350-bp fragment of the mitochondrial DNA control region. The results showed that the genetic diversity is very low between the populations (π=0.00116 for Alledeghi WR and π=0 for Sarite population). The population of Alledeghi WR is probably isolated from the population of Sarite, as they don’t share any haplotypes. As the population of Alledeghi WR is separated from the ones from Sarite and Kenya, applying more conservational programs in this area is needed to protect the genetic diversity of the Grévy’s zebras in this area.

  • 276.
    Kim, Chang-il
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Pyongyang University of Science & Technology.
    The Role of the C-terminal Tail of the ribosomal Protein S13 in Protein Synthesis2014Independent thesis Advanced level (degree of Master (One Year)), 40 credits / 60 HE creditsStudent thesis
  • 277.
    Kjellander, Ingrid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Vetenskap och värderingar - en aktörsanalys om genmodifierade grödor2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In this report I aim to highlight the importance of how biotechnology is looked upon insociety. When science meets society, such as in the form of GM crops being grown, it createsa meeting between science and values in society. I have chosen to investigate opinions ongenetically modified crops; an extreme case where biotechnology is discharged into naturalecosystems with the possibility of genetically modified organisms (GMO) to spread theirgenes irreversibly. To illustrate how society's perspective affects how biotechnologydevelops, I have interviewed twelve key actors in the GMO debate. The twelve intervieweeshave backgrounds in various subject fields associated with GMO and highlights the variousdifficulties that exist in the interaction between science and values. The actors are often moreconsistent with each other than is evident in the public debates. Above all, the result showsthat what they all lack is a good forum for discussion, a larger system of thinking and adifferent type of legislation. In my discussion I therefore suggest a new discussion forum,where several different players are invited to a dialogue that could lead to a better balancebetween science and values.

  • 278.
    Klaesson, Mårten
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Melin, Ellen
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Elin, Malmström
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Hillver, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Olsson, Felix
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Dencker, Julia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Kartläggning av resistensmekanismer hos nematoder samt framtagande av en resistensassay2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta arbete är en beställning från Vidilab AB som går ut på att kartlägga resistensmekanismer hos nematoder samt ta fram en resistensassay. Beställningen grundar sig i problematiken kring dagens metoder för resistensbestämning, som går ut på att analysera förekomsten av ägg i avföringen från betande djur innan respektive efter avmaskning. Vidilab efterlyser en molekylär diagnostikmetod för resistensbestämning innan boskapsdjuren behandlas med anthelmintika. Som avgränsning har projektet riktat in sig på resistensmekanismer hos nematoden Haemonchus contortus som i första hand parasiterar får. I projektet har i huvudsak förslag på tre tekniker tagits fram som skulle kunna användas för resistensbestämning hos H. contortus. Dessa tre metoder är allelspecifik PCR, RT-PCR och MALDI-TOF. Slutsatsen i detta projekt är att samtliga av dessa tre metoder har potential som molekylär diagnostikmetod. Dock krävs mer forskning kring H. contortus resistensmekanismer, storskalig sekvensering samt kartläggning av transkriptom och proteomikstudier innan teknikerna kan appliceras som standardiserade diagnostikmetoder.

  • 279.
    Klingberg, Josefine
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Kan klimatförändringarna leda till brunifiering och påverka dricksvattenkvaliteten i barrskogsbältet?2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Ytvattenfärgen i barrskogsbältet har sedan industrialismen på mitten av 1900-talet förändrats noterbart. Orsaken till detta är brunifiering och innebär att organiskt material från barrskogen samlar sig i sjöar. En påtaglig effekt av detta fenomen är förändringar i vattenfärg, ju mer löst organiskt material (dissolved organic matter, DOM), desto mörkare vattenfärg. Löst organiskt kol (dissolved organic carbon, DOC) kan komma från två olika källor som visat sig påverka vattenfärgen olika. Alloktont DOC är producerat utanför sjön i de omgivande markerna och ger mörkare färg än autoktont som är producerat inom sjön. Det har även visat sig att DOC inte alltid själv står för vattenfärgen utan att den även påverkas av Fe och andra ämnen bundna till DOC. Exakta processerna bakom brunifiering och hur dessa processer påverkas och samarbetar är ännu inte helt klarlagt. Huvudorsaken bakom brunifiering är klimatförändringar vilka ger förändrad hydrologi, men minskat surt nedfall är också en bidragande faktor. Trots att detta är klargjort finns det forskning som visat extrema DOC-koncentrationer i sjöar som inte går att förklara med något av dessa fenomen. Brunifieringens påverkan på ytvattnet kan leda till allt från ekosystemsförändringar till minskade rekreationsvärden såsom fiske och bad, vilket har en negativ påverkan på turistnäringen. Självklart påverkas även dricksvattenkvaliteten av kvaliteten på råvattnet, vilket i barrskogsbältet till stor del kommer från ytvattentäkter. Den hittills största hälsofaran i dricksvatten är patogena organismer, men på grund av brunifieringen kan detta komma att ändras. DOC är inte giftigt i sig själv men kan transportera med sig giftiga ämnen och i vattenreningsverk kan det organiska materialet reagera med desinfektanterna och bilda desinfektionsbiprodukter (DBP). DBPs bildas då organiskt material reagerar med starkt oxiderande desinfektanter såsom klor och ozon, vilka är vanligt använda i vattenreningsverk. En grupp av DBP som hittats i dricksvatten är trihalometan (THM) vilket är både mutagent och karcinogent. Om brunifieringen fortsätter i samma riktning som nu måste åtgärder vidtas för att bibehålla en god dricksvattenkvalité. Dessa åtgärder handlar om att placera vattenreningsverken nedströms i sjöarna för att minska DOC-koncentrationerna i råvattnet och i vissa fall att övergå från ytvatten till grundvatten som råvattentäkt. Då det finns luckor i kunskapen om brunifieringens orsaker och konsekvenser krävs mer forskning för att bättre förstå och motverka fenomenet och dess effekter. 

  • 280.
    Klingberg, Josefine
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Latrin från fritidsbåtar i Stockholms skärgård - innehåll, volym och påverkan på avloppsreningsverk och ekosystem2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The first of April 2015 a constitution came into force which comprises a prohibition of discharge of sewage from leisure boats in Swedish territorial waters. It was mandatory for leisure boat marinas already before this constitution to have waste reception facilities for waste, including sewage, from leisure boats. As a result of this many marinas and leisure boat clubs have pump out stations in order to receive sewage. This waste is then transferred to sewage treatment plants for treatment as household sewage. How the boat sewage is handled at the collection differs within Sweden. Some pump out stations are connected directly to the municipal sewer system, if the placing permits, while some have been denied to connect. One of the reasons for this difference is uncertainty about volume and content of the boat sewage and hence uncertainty in the effects it has on the sewage treatment process.

    This study was performed in order to fill these knowledge gaps and to investigate the impact of discharge on the ecosystem, as the first of its kind in Sweden. The study includes sampling and volume calculations and is part of a LOVA-project as a cooperation project between Norrtälje, Vaxholm and Värmdö municipalities, the Swedish Transportation Agency and Ecoloop AB. During the autumn 2016 four pump out stations within the participating municipalities were sampled as a part of the study. The analysis of boat sewage showed high concentrations of nutrients, oxygen consuming substances, and metals in comparison with household sewage. Analyzes of a selection of chemicals and bacteria were performed in order to demonstrate the possible use of sanitary fluids, which are used in toilets to prevent odors. Because of conflicting results and uncertainty in the analysis method used no detection of the use of sanitary liquids could be done and further analysis should be carried out.

    It is possible in most sewage treatment plants to add the boat sewage gradually and in that way dilute it. The dilution prevents the concentrated boat sewage to inhibit the biological processes performed by microorganisms in sewage treatment plants. The boat sewage can be a threat to the Revaq-certification of some sewage treatment plants. Revaq-certification guarantees that the sludge is of a quality that allows recycling to forestry and agriculture.

    Collection of boat sewage can cause sewage treatment plants to not meet their commitments in terms of treatment requirements, but the problems with discharge can be even more serious. Stockholm archipelago is located in the Baltic Sea which is one of the most affected seas with eutrophication as one of the greatest threats. Discharge of boat sewage contributes to eutrophication since it is very nutritious. According to a survey conducted within this study an average boat septic tank contains 34 l sewage. This is equivalent to for example 2.5 g phosphorus and 50 g nitrogen. Calculations based on the survey also shows that the total volume of boat sewage collected in pump out stations in the participating municipalities is 350 m3 per year.

    The introduction of the prohibition of discharge was motivated from an environmental and health point of view since it would reduce the supply of nutrients and infectious bacteria to the environment. The high content of nutrients and metals in the boat sewage would contribute to environmental problems when discharged. The impact on the environment in relation to other sources could not be shown in this study. The health aspect, on the other hand, is unmistakable since the boat sewage contains a high amount of bacteria.

  • 281.
    Kohout, Manuel
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Prioritizing islands for the eradication of invasive predators: Which islands in the Western Indian Ocean should be protected first2014Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Islands, constituting merely 5% of our planet’s land area, hold more than 20% of all existing terrestrial plant and vertebrate species. Dauntingly, islands are also among the places most severely affected by the extinction crisis we are facing today. Next to habitat destruction, the greatest threat to island biodiversity is invasive predators and the most effective way to deal with them is their removal. Crucially, eradication is an absolutely essential prerequisite for any subsequent restoration to be successful. In an aspiration to add to the gradually emerging efforts of channelling limited resources to the islands in most urgent need of protection, this study informs about island priorities in the Western Indian Ocean for the eradication of rats (Rattus spp.), cats (Felis catus) and mice (Mus musculus). Considering 318 islands within the region and using 77 affected bird species as surrogates for an island’s total conservation value, the overall strategy of the approach is one of return on investment, i.e. of conservation gain divided by conservation cost. The method strives to be complex and flexible enough to be adjustable to the specific goals of any conservation practitioner in the region, while, at the same time, simple and transparent enough, to be repeatable anywhere in the world. Novel is the inclusion of two variables increasing along probability curves, and measuring an island’s inundation and reinvasion risk. The result of the triage is a set of robust lists presenting the most important islands for immediate conservation actions. 

  • 282.
    Koning, Harmen Kornelis
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Localization and Characterization of the Enkephalin and Dynorphin expressing interneuron populations in the mouse spinal cord and validation of DREADD expression induced by virus injection2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The spinal cord dorsal horn is the location where primary afferent sensory neurons relay signals from periphery to the central nervous system. This location is of high interest for pain and itch related research because it is here that incoming signals are modulated by dorsal horn interneurons, highly heterogeneous populations that up/down regulate signals before conduction to sensory modules in the brain. This primary modulation is involved in diseases such as allodynia, hyperalgesia and chronic pruritus. We use fluorescence immunohistochemistry to determine the dorso-ventral distribution and neurochemical phenotype of two opioid signalling populations; enkephalin and dynorphin positive interneurons defined by the activity of respective promotor. The populations were found to be fairly similar in both distribution and transmitter phenotype. We also validated Cre driven expression of inhibitory and excitatory DREADDs to a control based on a mCherry proxy.

  • 283.
    Kozma, Radoslav
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Population and Conservation Biology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Siberian jay friendship test: A study on group cohesion2011Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Group and family living is an integral part of many animals’ ecology. Thus the behavior became associated with plenty of advantages as well as disadvantages. However, rarely has the actual concept of the group been investigated. Questions such as, “What constitutes a ‘group’?” and “Do the individuals within these ‘groups’ associate with each other frequently enough to actually enjoy the benefits of group living?” are seldom asked. With these questions in mind, the aim of this study was to use Siberian jay (Perisoreus infaustus) individuals in their territories to explore and shed more light on the issue of the extent of group living. A working definition of a ‘group’ was made and subsequently the birds were observed in their natural habitat in northern Sweden during several seasons. Consequently, a pair-wise coherence index (CI) was created to quantify the levels of association between the individuals within each territory in order to investigate which possible factors affect the extent of the observed cohesion. Results of the study indicate that pair-wise cohesion was strongly dependent on the kinship of the birds. Moreover, it was found that the alpha and kin birds had significantly higher coherence values than the non kin birds. Thus, within a territory, it was the alpha and the kin birds that formed the core of the group with the non kin birds being much less associated with the other individuals. This was in contrast to the hypothesis, which predicted alpha birds to form the core of the group solely, with kin birds having significantly lower coherence. Interestingly, no effect of habitat type and season was found on the cohesion of the territorial group. Moreover, further evidence of sub-grouping was found even on the kinship level, thus suggesting yet more complex interplay between group cohesion and the group members.  All in all, with the non kin birds having low coherence values, the study casts light on the fact that even if individuals are present in a territory, they might not necessarily be a tight unit and as such be unable to fully benefit from group living.

  • 284.
    Krieg, Therese
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Real-time monitoring of continuous fermentation by Raman spectroscopy2014Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The production of bio-ethanol from lignocellulosic material requires a more efficient process to be feasible and compete with products from fossil fuels. There is a need to rapidly and nondestructively be able to determine key components during fermentation. Raman spectroscopy is a technique, which can be used to monitor the fermentation process in real-time and provide information about key components which can be accessed immediately, thus facilitating process control. A continuous system with membrane cell recycling was set up and fermentations were performed using Saccharomyces cerevisiae ATCC 96581. Fermentations were performed to test for optimal dilution rates and operating times, the effect of different sugar concentrations in the media feed, and which position in the system was optimal for Raman data collection. Raman data and aliquot samples for HPLC validation were continuously collected throughout the fermentations. Raman data was analysed with PLS models to obtain component concentrations, for which RMSE was calculated in order to compare to HPLC validation set. Fermentations were performed with synthetic glucose media as well as with poplar hydrolysate. It was shown that the continuous system with membrane cell recycling could achieve a glucose-to-ethanol conversion of between 75-100%. The process could be sufficiently monitored by Raman spectroscopy, and predicted concentrations were within the range of the validation set in most cases. However, the error of prediction varied between the different fermentations.

  • 285.
    Kristoffersson, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Rolling circle transcription on smallest size double stranded DNA minicircles2010Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The RNA polymerase T7 is utilized as a component of motor complexes in DNA nanotechnology due to its high promotor specificity, the lack of external transcription factors and its very high processivity, but there is no experience of its application on small double stranded DNA circles. Circular templates from 210 to 126 bp in circumference sharing a common promotor termination motif were synthesized and transcription was monitored at end point on gel and in real time with a 2’ O methyl RNA molecular beacon. The RNAP T7 was found to be able to utilize circular dsDNA templates down to 126 bp with moderate impact on transcription rate for saturated systems and rolling circle transcription products were evident with denaturizing PAGE gel electrophoresis for templates down to 167 bp.

  • 286.
    Kruger, Åsa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organism Biology, Systematic Biology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    DNA-Barcoding Identification of Medicinal Roots from Morocco2008Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 287.
    Kryvokhyzha, Dmytro
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Department of Organismic and Evolutionary Biology, Harvard University, USA.
    Whole genome resequencing of Heliconius butterflies revolutionizes our view of the level of admixture between species2014Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The theory of "genomic islands of speciation" has been extensively debated during the last decade. This thesis not only supports this theory, but provides evidence that challenges previous beliefs on the level of admixture between species. The recently published Heliconius melpomene genome project reported apparent genomic paraphyly of H. pardalinus with regard to H. elevatus (Heliconius Genome Consortium 2012). Here, we investigate this pair of butterfly species more fully, firstly by using whole-genome resequence data, and secondly by analyzing additional geographic populations of both species, as well as outgroup taxa. Using a nuclear whole-genome phylogenetic analysis we also confirm that H. elevatus is paraphyletic. The genome-wide phylogenetic signal in H. pardalinus and H. elevatus does not indicate expected mutual monophyly of each species as it seems strongly distorted by a high level of admixture. However, several regions of the genome remain differentiated and do show the presumably original phylogenetic signal with mutual monophyly of H. pardalinus and H. elevatus. The genomic background is so homogenized that its level of differentiation (FST ~ 0.03) virtually implies panmixia. The pattern of a high level of homogenization across the genome with several regions of differentiation was consistent with a number of other statistics such as absolute divergence Dxy, nucleotide polymorphism π, number of fixed differences and with a sliding window phylogeny. The identified genomic islands of divergence comprise genes responsible for wing-patterning and chemosensation in Heliconius and some of these genes are found to be under positive selection, suggesting possible candidates of speciation.

  • 288.
    Kuehrer, Lukas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Exposure to the antihistamine diphenhydramine affects thermoregulation and increases righting time in the freshwater snail Planorbarius corneus2017Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Antihistamines have been shown to degrade poorly, and should be considered as contaminants that may pose risks to the aquatic ecosystem. Diphenhydramine (DPH) is a first generation antihistamine detected up to lower micrograms per litre downstream of wastewater treatment facilities. Freshwater snails like Planorbis corneus are ectotherms and behaviour plays an important role for the regulation of snail body temperature. In a laboratory experiment, it was tested if DPH affects the behavioural traits thermoregulation and righting time in P. corneus. Righting time was measured as the time snails took to right themselves from an upside down position. After a 24 hour exposure to three different sublethal concentrations (nominal concentrations: 10, 100, and 1000 µg/L) of DPH two thermoregulatory experiments (thermal preference (TPref) and maximum critical temperature (CTmax)) and one righting time experiment were performed. CTmax increased significantly from 37.5 °C to 39.7°C after exposure to 949 µg/L DPH. Minimal righting time was significantly increased in the lowest exposure concentration (8.21 µg/L DPH). No significant results were found in the TPref analyses. Collectively these results suggest that exposure to non-lethal concentrations of DPH affect behavioral traits like thermoregulation and righting time in freshwater snails. 

  • 289.
    Kullman, Robert
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Effects of urbanisation on fitness and floral morphology in Chamerion angustifolium2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    The full text will be freely available from 2020-02-27 10:00
  • 290.
    Kurland, Sara
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. McGill University.
    The population structure of natural populations of Californian stickleback (Gasterosteus aculeatus) in dynamic estuaries2015Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    There is still much to be understood regarding the role of natural selection in shaping adaptive divergence between wild populations, particularly regarding the relative roles that stochastic and selective mechanisms play in this process. An excellent example of adaptive divergence is the parallel evolution of the threespine stickleback (Gasterosteus aculeatus), where completely plated marine fish have repeatedly evolved towards armor reduction in freshwater environments. Interestingly, the phenotypic trajectories along which this species has adapted vary along its distribution range and polymorphisms in genes crucial for these adaptations still exist. By studying wild populations of threespine stickleback in dynamic estuaries along the coast of Santa Cruz, California, this study is an initial part of a project aiming to shed further light on the mechanisms of adaptive divergence. Questions to be answered here regard the population structure of these insofar unstudied populations. Seven putatively neutral and two microsatellite markers associated to genes known to facilitate freshwater adaptations were considered. Levels of diversification were estimated across and within populations, using estimates of Fst, FIS and heterozygosity. The level of neutral population structure was low and no evidence of geographic isolation was found. Estimates of selection acting on the population did not indicate strong divergent selection at two adaptive markers as compared to the neutral ones. This study concludes that the balance between selective and neutrally selective processes for adaptive divergence may be more complex than what has typically been described for wild stickleback populations.

  • 291.
    Källgren, Joanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Strukturella och funktionella studier av fyra enzymer involverade i cellväggsbiosyntes hos Mycobacterium tuberculosis2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The pathogenic bacterium Mycobacterium tuberculosis (Mt) is the causative agent of tuberculosis, a widespread and fatal infectious disease. Today, treatment against tuberculosis involves a combination of drugs, which need to be taken for at least six months and which often causes severe side effects. Therefore, new drugs that are more effective and that give fewer side effects are needed. A characteristic feature of the Mt bacterium is its very complex and thick cell wall, which prevents many potential drug molecules from penetrating it. Inhibiting any one of the enzymes that are involved in its biosynthesis would therefore seem to be a good strategy for eliminating the Mt bacteria. The aim of this study was to characterize four enzymes involved in Mt cell wall biosynthesis. In order to do that, they were produced recombinantly in E. coli and purified. Crystallization experiments were set up in order to produce diffracting crystals, with the aim of structure determination and drug design.

  • 292.
    Källén, Ingela
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Fjällfågelinventering i Dalarna: Vilka fågelarter finns där och i vilken miljö hittar man dem?2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Purpose of the study was to investigate the bird species found in the mountains of Dalarna, in what environment you find them, and if there was a separation between species in choice of nesting site. The investigation was performed in the nature reserve Drevfjällen concentrated around the highest mountain top Härjehågna. For several years, this area has been inventoried by the County administration of Dalarna as part of their environmental monitoring work. Data from the 2011-2013 was used in this report. The numbers of observed species and habitats were compiled. For the study about habitat selection, five species were selected for a closer look. These species were Brambling Fringilla montifringilla, Willow Warbler Phylloscopus trochilus, Common Redstart Phoenicurus phoenicurus, Tree Pipit Anthus trivialis and Meadow Pipit Anthus pratensis.

     

    A total of 63 species were observed during the period 2011-2013. Ten orders of birds are represented and the majority are passerines, waders come in second place. The species selected to be studied further following can be said: The Tree Pipit has the strongest preference for coniferous forest and is totally lacking in the open environment but there you often find the Meadow Pipit. Brambling and Common Redstart sings mostly inside the coniferous forest and willow warbler is found in all environments.

     

    When nature is complex, it is difficult to say anything definitive in terms of niche separation. But the Tree Pipit and Meadow Pipit are two very similar species that have completely different habitat. This may be a consequence of competition which led to a shift in the niche for the Meadow Pipit. Willow Warbler has a broad niche in terms of habitat and should therefore not be picky either with regard to choice of food or habitat. Willow Warbler is Sweden's most common bird and a broad niche is an excellent strategy for this species.

  • 293.
    Landbecker, David
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Utvärdering av Naturvårdsverkets bedömningsgrunder för makrofyter i sjöar2011Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    According to the Water Framework Directive of the European Union, macrophytes should be used as indicators in the ecological and environmental monitoring of lakes. In the member state Sweden the Environmental Protection Agency has elaborated assessment criteria for determining lake status based on macrophytes. The main focus of this thesis is to evaluate the efficiency of the assessment criteria for macrophytes. In addition the concordance between the ecological status classes of the four quality factors included was analysed.

    The assessment criteria for macrophytes are based on the total phosphorus preference of the respective species. The focus is thus mainly on the nutrient level of the investigated lakes and the environmental problem monitored is eutrophication. Macrophytes are one of the five biological quality factors used for lakes. The others are phytoplankton, diatoms, benthic fauna and fish. The two latter were included in this thesis. In addition to the biological factors the chemical factor, nutrients in lakes, i.e. the total phosphorus, was included. The macrophyte composition was investigated in two eutrophic Uppland lakes: Lake Trehörningen and Lake Edasjön. Since the assessment criteria were launched in 2007 there have been problems reported regarding the outcome of the methods. The results are sometimes inconclusive for eutrophicated lakes and especially for lakes with naturally high levels of nutrients. In this study the macrophyte species composition was compared with the nutrient level of different lakes. Some species were found in equal shares in oligotrophic lakes as in eutrophic, e.g. Nymphaea candida and Nuphar lutea. Hence they were considered less suitable as elements in the method evaluated. A couple of species were present in predominantly oligotrophic (e.g. Lobelia dortmanna) or eutrophic (e.g. Hydrocharis morsus-ranae) lakes, respectively. They were regarded as better indicators since they ”preferred” lakes either poor or rich in nutrients. It is important to point out that all the other biological quality factors used, except for macrophytes, are multimetric.

    I conclude that more parameters are needed for evaluation of macrophytes in lakes. Tentatively, the degree of coverage of the plants and algae, the presence and degree of coverage of invasive nonnative species, lake lowerings and the consequent composition and abundance change, all should be tested as additional parameters.  A high level of concordance was verified for the status classifications of the four quality factors in lakes of oligotrophy as well as in lakes of eutrophy, i.e. no particular  pattern based on trophy level was found. The macrophyte inventories of the two Uppland lakes both resulted in a moderate ecological status for macrophytes.

  • 294.
    Larsson, Caroline
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Bacterial Sortase A as a drug target2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Sortase A is a housekeeping enzyme of Gram-positive bacteria that catalyses the anchoring of surface proteins to the bacterial peptidoglycan. The enzyme works to establish an interaction between bacteria and host cells and is essential for pathogenesis. This makes Sortase A a potential suitable target for inhibition, in order to treat bacterial infections.

    In this degree project Sortase A from Staphylococcus aureus was explored and potential inhibitors were investigated by performing enzyme activity and bacterial binding assays. A robust FRET assay was developed and optimized for a recombinant version of the enzyme and serves as a good starting point for studying inhibition.

  • 295.
    Larsson, Erika
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Endocrine disruption of the fungicide propiconazole in the frog Xenopus tropicalis: Effects on the aromatase activity and egg development2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Amphibian populations around the world are decreasing, and endocrine disrupting chemicals have been suggested as a part of the problem. The fungicide propiconazole is used in agriculture in many countries. It works as a fungicide by inhibiting CYP51, affecting the fungi cell membrane, but it has also been proven to inhibit aromatase, CYP19. Aromatase converts androgens to estrogen and is important for sexual differentiation in the early development and in reproduction in vertebrates. The aim of this study was to investigate the effect of propiconazole on the aromatase activity in brains from the West African clawed frog (Xenopus tropicalis), after larval and adult exposure and on aromatase activity in ovaries after adult exposure. Furthermore, effects on egg development was determined after adult exposure.

    Tadpoles were exposed to propiconazole (0, 25, and 250 µg/L) from three days after hatching until metamorphosis. In a former study, female adult X. tropicalis were exposed to 0 and 250 µg/L propiconazole during 4 weeks. The result of the aromatase activity measurements showed that 250 µg/L propiconazole increased brain aromatase activity after larval exposure. Brain and ovarian aromatase activity was also increased compared to the controls after adult exposure to 250µg/L propiconazole. The increased aromatase activity could reflect a compensatory response to decreased estrogen levels. Propiconazole had a significant impact on egg development, with an increased proportion of atretic oocytes and a decreased proportion of vitellogenic oocytes compared to the controls. The effect on egg development seems to be the result of a low estrogen level. The results suggest that exposure to propiconazole 250 µg/L could have a negative impact on X. tropicalis fertility.  Further studies to determine impacts of environmental exposure concentrations are needed to evaluate the risk of azoles to amphibian reproduction.

  • 296.
    Larsson, Hanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Den smältande polarisens effekt på de endemiska valarna i Arktis2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Klimatförändringarna har en stor påverkan på de arktiska valarna grönlandsval (Balaena mysticetus), vitval (Delphinapterus leucas) och narval (Monodon monoceros), mer än vad som tros vid en första tanke. I dagsläget får dessa valar utstå stora utmaningar som troligenkan komma att förvärras i framtiden om inte isens smältande kan bromsas. En del av utmaningarna innebär att valarna måste genomgå stora förändringar för att överleva, vilket innebär att deras förmåga att anpassa sig spelar en stor roll. Människans jakt på valen har alltid varit ett stort problem för de arktiska valarna, tack vare restriktioner om fångstkvoter och vem som får jaga val ser framtiden ljusare ut i alla fall för grönlandsvalen och vitvalen. För narvalen ser det dock inte lika ljust ut eftersom det är en art som är känsligare än många andra arktiska arter för effekterna som den globala uppvärmningen har på den arktiska miljön.

    I dagsläget har en del effekter på valarna blivit synliga såsom ändrade migrationsvanor och ökad predation. På grund av bristande data från perioden innan klimatförändringarna är detsvårt att dra konkreta slutsatser, därför fokuserar mycket forskning på att förutse vad som kommer att ske i framtiden. Fokus på framtiden är viktigt eftersom det som sker idag redan är försent att göra någonting åt, det vi kan göra är att se till att det inte blir ännu värre.

    Den smältande isens effekter är svåra att skilja på då de överlappar en del, till exempel leder tillgången på föda till förändringar i habitat. Man har i dagsläget sett små skillnader i tillgång på föda, beståndet av istorsken har minskat, eftersom det är en viktig föda för de arktiska valarna kan det ha en effekt. En minskning av en viss typ av plankton har också observerats och eftersom ingen ersättande art har setts kommer detta få effekter på näringsväven i de arktiska haven och därmed alla arter som lever där inklusive de arktiska valarna. I framtiden tror man att primärproduktionen kommer att öka på grund av den höjda vattentemperaturen och den ökande ytan med öppet vatten, detta kommer eventuellt ha en positiv effekt på de arktiska valarna.

  • 297.
    Leal, Luis
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Before speciation: adaptive evolution of diapause regulation in common wood-white butterflies (Leptidea sinapis)2017Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
  • 298.
    Lee, Hyeun-Ji
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Compensatory growth: the relationship between body size and mass at emergence and subsequent mass gain in the emerald damselfly, Lestes sponsa2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 299.
    Lee, Iwa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Environmental Toxicology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Quantification of p53-expressing cells and neurodegenerative cells in neonatal mouse brain after exposure to PBDE 99, TBBPA or ketamine2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 300.
    Leggatt, Rosalind A.
    et al.
    Fisheries & Oceans Canada, Ctr Aquaculture & Environm Res, 4160 Marine Dr, W Vancouver, BC V7V 1N6, Canada..
    Sundström, L. Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Fisheries & Oceans Canada, Ctr Aquaculture & Environm Res, 4160 Marine Dr, W Vancouver, BC V7V 1N6, Canada..
    Vandersteen, Wendy E.
    Fisheries & Oceans Canada, Ctr Aquaculture & Environm Res, 4160 Marine Dr, W Vancouver, BC V7V 1N6, Canada.;Miracle Springs Inc, 12443 Stave Lake Rd, Mission, BC V2V 0A6, Canada..
    Devlin, Robert H.
    Fisheries & Oceans Canada, Ctr Aquaculture & Environm Res, 4160 Marine Dr, W Vancouver, BC V7V 1N6, Canada..
    Alternate Directed Anthropogenic Shifts in Genotype Result in Different Ecological Outcomes in Coho Salmon Oncorhynchus kisutch Fry2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 2, article id e0148687Article in journal (Refereed)
    Abstract [en]

    Domesticated and growth hormone (GH) transgenic salmon provide an interesting model to compare effects of selected versus engineered phenotypic change on relative fitness in an ecological context. Phenotype in domestication is altered via polygenic selection of traits over multiple generations, whereas in transgenesis is altered by a single locus in one generation. These established and emerging technologies both result in elevated growth rates in culture, and are associated with similar secondary effects such as increased foraging, decreased predator avoidance, and similar endocrine and gene expression profiles. As such, there is concern regarding ecological consequences should fish that have been genetically altered escape to natural ecosystems. To determine if the type of genetic change influences fitness components associated with ecological success outside of the culture environments they were produced for, we examined growth and survival of domesticated, transgenic, and wild-type coho salmon fry under different environmental conditions. In simple conditions (i. e. culture) with unlimited food, transgenic fish had the greatest growth, while in naturalized stream tanks (limited natural food, with or without predators) domesticated fish had greatest growth and survival of the three fish groups. As such, the largest growth in culture conditions may not translate to the greatest ecological effects in natural conditions, and shifts in phenotype over multiple rather than one loci may result in greater success in a wider range of conditions. These differences may arise from very different historical opportunities of transgenic and domesticated strains to select for multiple growth pathways or counter-select against negative secondary changes arising from elevated capacity for growth, with domesticated fish potentially obtaining or retaining adaptive responses to multiple environmental conditions not yet acquired in recently generated transgenic strains.

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