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  • 1.
    Abbey-Lee, Robin N.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Kreshchenko, Anastasia
    Mechanical and Aeronautical Engineering Division L5, Department of Mechanical, Aerospace & Civil Engineering, Dalton Nuclear Institute, FSE Research Institutes,The University of Manchester, UK.
    Fernandez Sala, Xavier
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Petkova, Irina
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. School of Biological Sciences, Centre for Ecology,Evolution and Behaviour, Royal Holloway University of London, Egham UK.
    Løvlie, Hanne
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Effects of monoamine manipulations on the personality and gene expression of three-spined sticklebacks2019In: Journal of Experimental Biology, ISSN 0022-0949, E-ISSN 1477-9145, Vol. 222, no 20, article id jeb211888Article in journal (Refereed)
    Abstract [en]

    Among-individual behavioral differences (i.e. animal personality) are commonly observed across taxa, although the underlying, causal mechanisms of such differences are poorly understood. Animal personality has been correlated with physiological functions as well as fitness-related traits. Variation in many aspects of monoamine systems, such as metabolite levels and gene polymorphisms, has been linked to behavioral variation. Therefore, here we experimentally investigated the potential role of monoamines in explaining individual variation in personality, using two common pharmaceuticals that respectively alter the levels of serotonin and dopamine in the brain: fluoxetine and ropinirole. We exposed three-spined sticklebacks, a species that shows animal personality, to either chemical alone or to a combination of the two chemicals, for 18 days. During the experiment, fish were assayed at four time points for the following personality traits: exploration, boldness, aggression and sociability. To quantify brain gene expression on short- and longer-term scales, fish were sampled at two time points. Our results show that monoamine manipulations influence fish behavior. Specifically, fish exposed to either fluoxetine or ropinirole were significantly bolder, and fish exposed to the two chemicals together tended to be bolder than control fish. Our monoamine manipulations did not alter the gene expression of monoamine or stress-associated neurotransmitter genes, but control, untreated fish showed covariation between gene expression and behavior. Specifically, exploration and boldness were predicted by genes in the dopaminergic, serotonergic and stress pathways, and sociability was predicted by genes in the dopaminergic and stress pathways. These results add further support to the links between monoaminergic systems and personality, and show that exposure to monoamines can causally alter animal personality.

  • 2.
    Abrouk, Michael
    et al.
    Institute of Experimental Botany, Centre of the Region Hana for Biotechnological and Agricultural Research, Olomouc, Czech Republic.
    Balcarkova, Barbora
    Institute of Experimental Botany, Centre of the Region Hana for Biotechnological and Agricultural Research, Olomouc, Czech Republic.
    Simkova, Hana
    Institute of Experimental Botany, Centre of the Region Hana for Biotechnological and Agricultural Research, Olomouc, Czech Republic.
    Kominkova, Eva
    Institute of Experimental Botany, Centre of the Region Hana for Biotechnological and Agricultural Research, Olomouc, Czech Republic.
    Martis, Mihaela-Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences. Institute for Bioinformatics and Systems Biology, Helmholtz Center Munich, Neuherberg, Germany.
    Jakobson, Irena
    Department of Gene Technology, Tallinn University of Technology, Akadeemia tee 15, Tallinn 19086, Estonia.
    Timofejeva, Ljudmilla
    Department of Gene Technology, Tallinn University of Technology, Akadeemia tee 15, Tallinn 19086, Estonia.
    Rey, Elodie
    Institute of Experimental Botany, Centre of the Region Hana for Biotechnological and Agricultural Research, Olomouc, Czech Republic.
    Vrana, Jan
    Institute of Experimental Botany, Centre of the Region Hana for Biotechnological and Agricultural Research, Olomouc, Czech Republic.
    Kilian, Andrzej
    Diversity Arrays Technology Pty Ltd, Yarralumla, ACT2600, Australia.
    Järve, Kadri
    Department of Gene Technology, Tallinn University of Technology, Akadeemia tee 15, Tallinn 19086, Estonia.
    Dolezel, Jaroslav
    Institute of Experimental Botany, Centre of the Region Hana for Biotechnological and Agricultural Research, Olomouc, Czech Republic.
    Valarik, Miroslav
    Institute of Experimental Botany, Centre of the Region Hana for Biotechnological and Agricultural Research, Olomouc, Czech Republic.
    The in silico identification and characterization of a bread wheat/Triticum militinae introgression line: Characterization of alien introgression in wheat2017In: Plant Biotechnology Journal, ISSN 1467-7644, E-ISSN 1467-7652, Vol. 15, no 2, p. 249-256Article in journal (Refereed)
    Abstract [en]

    The capacity of the bread wheat (Triticum aestivum) genome to tolerate introgression from related genomes can be exploited for wheat improvement. A resistance to powdery mildew expressed by a derivative of the cross bread wheat cv. Tähti ⨯ T. militinae (Tm) is known to be due to the incorporation of a Tm segment into the long arm of chromosome 4A. Here, a newly developed in silico method termed RICh (rearrangement identification and characterization) has been applied to characterize the introgression. A virtual gene order, assembled using the GenomeZipper approach, was obtained for the native copy of chromosome 4A; it incorporated 570 4A DArTseq markers to produce a zipper comprising 2,132 loci. A comparison between the native and introgressed forms of the 4AL chromosome arm showed that the introgressed region is located at the distal part of the arm. The Tm segment, derived from chromosome 7G, harbors 131 homoeologs out of the 357 genes present on the corresponding region of Chinese Spring 4AL. The estimated number of Tm genes transferred along with the disease resistance gene was 169. Characterizing the introgression's position, gene content and internal gene order should facilitate not only gene isolation, but may also be informative with respect to chromatin structure and behavior studies.

  • 3.
    Alkaissi, Hammoudi
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Ekstrand, Jimmy
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Jawad, Aksa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Nielsen, Jesper Bo
    University of Southern Denmark, Denmark.
    Havarinasab, Said
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Söderkvist, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Hultman, Per
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Genome-Wide Association Study to Identify Genes Related to Renal Mercury Concentrations in Mice2016In: Journal of Environmental Health Perspectives, ISSN 0091-6765, E-ISSN 1552-9924, Vol. 124, no 7, p. 920-926Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Following human mercury (Hg) exposure, the metal accumulates in considerable concentrations in kidney, liver, and brain. Although the toxicokinetics of Hg have been studied extensively, factors responsible for interindividual variation in humans are largely unknown. Differences in accumulation of renal Hg between inbred mouse strains suggest a genetic interstrain variation regulating retention or/and excretion of Hg. A. SW, DBA/2 and BALB/C mouse strains accumulate higher amounts of Hg than B10.S.

    OBJECTIVES: We aimed to find candidate genes associated with regulation of renal Hg concentrations.

    METHODS: A. SW, B10.S and their F1 and F2 offspring were exposed for 6 weeks to 2.0 mg Hg/L drinking water. Genotyping with microsatellites was conducted on 84 F2 mice for genome-wide scanning with ion pair reverse-phase high-performance liquid chromatography (IP RP HPLC). Quantitative trait loci (QTL) were established. Denaturing HPLC was used to detect single nucleotide polymorphisms for haplotyping and fine mapping in 184 and 32 F2 mice, respectively. Candidate genes (Pprc1, Btrc and Nfkb2) verified by fine mapping and QTL were further investigated by real-time polymerase chain reaction. Genes enhanced by Pprc1 (Nrf1 and Nrf2) were included for gene expression analysis.

    RESULTS: Renal Hg concentrations differed significantly between A. SW and B10. S mice and between males and females within each strain. QTL analysis showed a peak logarithm of odds ratio score 5.78 on chromosome 19 (p = 0.002). Haplotype and fine mapping associated the Hg accumulation with Pprc1, which encodes PGC-1-related coactivator (PRC), a coactivator for proteins involved in detoxification. Pprc1 and two genes coactivated by Pprc1 (Nrf1 and Nrf2) had significantly lower gene expression in the A. SW strain than in the B10. S strain.

    CONCLUSIONS: This study supports Pprc1 as a key regulator for renal Hg excretion.

  • 4.
    Andersson, Johanna
    et al.
    Linköping University, Department of Social and Welfare Studies, Learning, Aesthetics, Natural science. Linköping University, Faculty of Educational Sciences.
    Tibell, Lena
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Educational Sciences.
    Exploring childrens' views of what's inside the body2012Conference paper (Refereed)
    Abstract [en]

    The importance of living a healthy life in an everyday context is promoted in schools and preschools. The discussion often focuses on what food is healthy, and that one should eat enough but not too much. The connection between food and beverages and their role in the body is seldom discussed. Students’ ideas about how the human body functions have been investigated in several studies but few have focused on young children. In this study, we investigate young children’s conceptions related to this topic and how their ideas develop. Seventy-nine pre- and primary school children, aged 4-11, participated in individual focus interviews wherein the children were asked to draw and explain their understanding. Our results confirm several findings observed by other workers. However, in contrast with earlier studies, 10 of seventeen 4-5 year-old children indicated the stomach, and more than half of those children described how food can be utilized in the body to extract energy. Furthermore, the brain was among the most commonly mentioned organs cross all age groups. Interestingly, the level of expertise varied and did not covariate with age. For example, five of eight of the 4 year-old children draw 5-8 organs, while a single 10 year-old child could only mention three. Similarly, two of thirteen 7-year old children provided an almost completely correct description of the digestive tract and its function, while most of the older children expressed a much less developed understanding. The results reflect the wide range of different conceptual ideas that teachers confront in a day-to-day classroom context.

  • 5.
    Andersson, Johanna
    et al.
    Linköping University, Department of Social and Welfare Studies, Learning, Aesthetics, Natural science. Linköping University, Faculty of Educational Sciences.
    Tibell, Lena A.E.
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Educational Sciences.
    Children's reasoning and representations about living and non-living things2013Conference paper (Refereed)
    Abstract [en]

    Understanding of the concept ‘life’ and what characterise ‘living things’ is important as a foundation for learning in biology. In a more general view, this understanding can make children develop awareness, respect and responsibility for life as members of a society and in decision making for sustainable development. The present pilot study aim to investigate 5-6 year old pre-school children’s reasoning and representations about living and nonliving things. In cognitive developmental research, the concept of life is well investigated but, questions still remain regarding how children reason around and represent these concepts. Previous research has found that children have difficulties in including plants as living things. Moreover, it is found that young children include e.g. the sun, clouds and rocks as living things. The methods that have been used are often quantitative and use picture-cards with different objects for the children to categorize. In the present pilot study a modified methodology was applied. Children’s drawings of what they consider as living and non-living were collected and picture-cards were used as point of departure for reasoning. In interviews the children were encouraged to explain and express their ideas. The drawings and the cards mainly worked as a meaning making tool for the children. Results from the study will be presented and discussed. 

  • 6.
    Andersson, Jonathan
    et al.
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Kozlov, Vladimir
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Radosavljevic, Sonja
    Stockholm Resilience Centre, Stockholm University, Stockholm, Sweden.
    Tkachev, Vladimir
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Wennergren, Uno
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering.
    Density-Dependent Feedback in Age-Structured Populations2019In: Journal of Mathematical Sciences, ISSN 1072-3374, E-ISSN 1573-8795, Vol. 242, no 1, p. 2-24Article in journal (Refereed)
    Abstract [en]

    The population size has far-reaching effects on the fitness of the population, that, in its turn influences the population extinction or persistence. Understanding the density- and age-dependent factors will facilitate more accurate predictions about the population dynamics and its asymptotic behaviour. In this paper, we develop a rigourous mathematical analysis to study positive and negative effects of increased population density in the classical nonlinear age-structured population model introduced by Gurtin \& MacCamy in the late 1970s. One of our main results expresses the global stability of the system in terms of the newborn function only. We also derive the existence of a threshold population size implying the population extinction, which is well-known in population dynamics as an Allee effect.

  • 7.
    Andersson, Rebecca
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    An Evaluation of Two Presumptive Blood Tests and Three Methods to Visualise Blood2017Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The aim of this study was to validate the two presumptive blood tests LMG, LCV and the three visualising blood methods Bluestar Forensics, Lumiscene and the Ruhoff method. The methods’ sensitivity, durability, matrices effects, false positive results and the methods effect on subsequent DNA analysis were studied. DNA analyses were also performed to assess the detection limit of the forensic DNA analysis. Drops of diluted blood were applied on different absorptive matrices and the sensitivity was investigated. The solutions were also placed under different conditions to investigate the durability of the solutions. The solutions were applied upon panels using different chemicals and materials and the false positive results were studied. The DNA analyses were performed by diluting the blood with Bluestar Forensics, the hydrogen peroxide method, the Ruhoff method and deionised water. The study showed that the LMG with a 3 % H2O2 concentration performs the best and it is suited for practical casework. The positive results of LMG was easier to interpret than those of LCV, this is probably due to the fixative agent of the used LCV solution. Bluestar Forensics and Lumiscene did perform similar on the different matrices tested, but the Lumiscene solution had a slightly higher durability. The results strongly indicate that the Ruhoff method can be used without luminol, hence only as a hydrogen peroxide solution (the hydrogen peroxide method). All three visualising blood methods decreases chances of retrieving a positive DNA profile, however the visualising blood methods could be used if the blood cannot be found in any other way. A DNA profile was obtained from the one blood sample analysed at dilution of 1:256 in deionized water.

  • 8.
    Bunnfors, Kalle
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Synthesis and electrochemical characterisation of processable polypyrrole boronic acid derivatives for carbohydrate binding2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Conducting polymers have been widely explored for many different purposes including sensing. In thisthesis the conducive properties of pyrrole and the carbohydrate binding properties of boronic acid iscombined to make a reagent-free detector for carbohydrates. The polymer is manufactured in form ofparticles in the μm scale to create a porous film which has a high surface to volume ratio.The material was characterised and the binding properties were evaluated for galactose and glucose.Proof of binding was found via both electrochemical methods and QCM-D. A correlation between R2 value and concentration of substrate was found which enables measurement of concentration of carbohydratesin unknown samples.

  • 9.
    Bélteky, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Chicken domestication: Effects of tameness on brain gene expression and DNA methylation2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Domestication greatly increases phenotypic variation in a short time span, with selection for a single phenotype and a plethora of associated phenotypic changes as an outcome of the process. The domestication process influences the underlying genomic architecture of a species, and the success and speed of the process is likely influenced by it. The main aims of my thesis was to study how domestication affects the brain of chickens: specifically changes in morphology, gene expression, and DNA methylation. Differences in gene expression and DNA methylation between White Leghorn and Red Junglefowl chickens were mapped, and inheritance of these patterns were quantified, indicating a faithful transmission of breed-specific epigenetic markers. Selection on the behavioral trait fearfulness, generated high and low fearful lines of Red Junglefowl. Both the parental population and the fifth selected generation were used for the analyses in this thesis. One experiment studied morphological changes in the brain and other vital organs, and found that relative total brain size increased in high fearful birds, as a consequence of an increase in cerebral hemisphere size in high fearful birds and not in low fearful birds. Also, the relative heart, liver, spleen and testis size increased in high fearful birds, indicating correlated morphological changes with selection for fearfulness. Two additional experiments examined differential gene expression in the hypothalamus and the anterior cerebral hemisphere. The hypothalamus differed in expression of genes with reproductive and immunological functions, whilst the cerebral hemisphere differed in expression of genes related to social behaviors and neurological functions especially those upregulated in low fearful birds.  These results indicate the occurrence of tissue- and species-specific changes in gene expression as overlap with other domestication events were nearly nonexistent. A fourth experiment sought to associate the change in fear levels and gene expression differences with DNA methylation. Chromosomal regions with differential DNA methylation between high and low fearful birds were identified, and genes in these regions had annotated functions relevant to phenotypic differences between the selection lines. This thesis is the first to study the genetic alterations of domestication using the wild ancestor of an already domesticated species to repeat the domestication process selecting against fear of humans. The findings corroborate results from previous comparisons of wild and domestic animals, and further support the theory that rigorous selection for a behavioral trait can cause a cascade of genetic and epigenetic changes facilitating the domestication of a population.

    List of papers
    1. Heritable genome-wide variation of gene expression and promoter methylation between wild and domesticated chickens
    Open this publication in new window or tab >>Heritable genome-wide variation of gene expression and promoter methylation between wild and domesticated chickens
    Show others...
    2012 (English)In: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 13, no 59Article in journal (Refereed) Published
    Abstract [en]

    Variations in gene expression, mediated by epigenetic mechanisms, may cause broad phenotypic effects in animals. However, it has been debated to what extent expression variation and epigenetic modifications, such as patterns of DNA methylation, are transferred across generations, and therefore it is uncertain what role epigenetic variation may play in adaptation. Here, we show that in Red Junglefowl, ancestor of domestic chickens, gene expression and methylation profiles in thalamus/hypothalamus differ substantially from that of a domesticated egg laying breed. Expression as well as methylation differences are largely maintained in the offspring, demonstrating reliable inheritance of epigenetic variation. Some of the inherited methylation differences are tissue-specific, and the differential methylation at specific loci are little changed after eight generations of intercrossing between Red Junglefowl and domesticated laying hens. There was an over-representation of differentially expressed and methylated genes in selective sweep regions associated with chicken domestication. Hence, our results show that epigenetic variation is inherited in chickens, and we suggest that selection of favourable epigenomes, either by selection of genotypes affecting epigenetic states, or by selection of methylation states which are inherited independently of sequence differences, may have been an important aspect of chicken domestication.

    Place, publisher, year, edition, pages
    BioMed Central, 2012
    Keywords
    Domestication, gene expression, tiling array, behaviour, methylation
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:liu:diva-70159 (URN)10.1186/1471-2164-13-59 (DOI)000301440800001 ()
    Note

    funding agencies|Swedish Research Council| 2008-14496-59340-36 |Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning| 221 2007 838 |

    Available from: 2011-08-22 Created: 2011-08-22 Last updated: 2019-03-05Bibliographically approved
    2. Domestication and tameness: brain geneexpression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology
    Open this publication in new window or tab >>Domestication and tameness: brain geneexpression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology
    Show others...
    2016 (English)In: Royal Society Open Science, E-ISSN 2054-5703, no 3, article id 160033Article in journal (Refereed) Published
    Abstract [en]

    The domestication of animals has generated a set of phenotypicmodifications, affecting behaviour, appearance, physiologyand reproduction, which are consistent across a range ofspecies. We hypothesized that some of these phenotypes couldhave evolved because of genetic correlation to tameness,an essential trait for successful domestication. Starting froman outbred population of red junglefowl, ancestor of alldomestic chickens, we selected birds for either high or lowfear of humans for five generations. Birds from the fifthselected generation (S5) showed a divergent pattern of growthand reproduction, where low fear chickens grew larger andproduced larger offspring. To examine underlying geneticmechanisms, we used microarrays to study gene expressionin thalamus/hypothalamus, a brain region involved in fearand stress, in both the parental generation and the S5. Whileparents of the selection lines did not show any differentiallyexpressed genes, there were a total of 33 genes with adjustedp-values below 0.1 in S5. These were mainly related to spermfunction,immunological functions, with only a few known tobe relevant to behaviour. Hence, five generations of divergentselection for fear of humans produced changes in hypothalamicgene expression profiles related to pathways associated withmale reproduction and to immunology. This may be linked to the effects seen on growth and size of offspring. These results support the hypothesis thatdomesticated phenotypes may evolve because of correlated effects related to reduced fear of humans.

    Place, publisher, year, edition, pages
    Royal Society Publishing, 2016
    Keywords
    artificial selection, gene expression, microarray, chicken, fearfulness
    National Category
    Ecology
    Identifiers
    urn:nbn:se:liu:diva-130501 (URN)10.1098/rsos.160033 (DOI)000384411000002 ()
    Note

    Funding agencies:  Research council Formas; Vetenskapsradet; ERC [322206]

    Available from: 2016-08-11 Created: 2016-08-11 Last updated: 2017-11-28
  • 10.
    Curtsdotter, Alva
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, The Institute of Technology.
    Binzer, Amrei
    J.F. Blumenbach Institute of Zoology and Anthropology, Georg-August University, Göttingen, Germany.
    Brose, Ulrich
    J.F. Blumenbach Institute of Zoology and Anthropology, Georg-August University, Göttingen, Germany.
    Ebenman, Bo
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, The Institute of Technology.
    The interaction between species traits and community properties determine food web resistance to species loss2014Manuscript (preprint) (Other academic)
    Abstract [en]

    The ability to identify the ecosystems most vulnerable to species loss is fundamental for the allocation of conservation efforts. With this aim, the traits of keystone species have been investigated, as have the properties defining systems especially sensitive to species loss. However, these two have rarely been investigated in relation to each other. Here we show, that the traits of the species primarily lost act in conjunction with the properties of the food web from which it is lost, in determining the resistance of the system. We find that the extent of bottom-up extinction cascades is determined mainly by traits related to food web topology, while traits related to population dynamics govern the extent of top-down cascades. As different disturbances affect species with different traits, this interaction implies that the characteristics defining a sensitive community depend on the disturbance it is subjected to.

  • 11.
    Curtsdotter, Alva
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, The Institute of Technology.
    Münger, Peter
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Physics. Linköping University, The Institute of Technology.
    Norberg, Jon
    Department of Systems Ecology, Stockholm University/Stockholm Resilience Centre, Stockholm University, Sweden.
    Åkesson, Anna
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Ebenman, Bo
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, The Institute of Technology.
    The strength of interspecific competition modulates the eco-evolutionary response to climate change2014Manuscript (preprint) (Other academic)
    Abstract [en]

    Climate change is predicted to have major implications for global biodiversity. Dispersal and evolution may become crucial for species survival, as species must either adapt or migrate to track the changing climate. However, migration and evolution do not occur in vacuum – the biotic community in which these processes play out may modulate their effect on biodiversity. Here, we use an eco-evolutionary, spatially explicit, multi-species model that allows us to examine the interactive effects of competition, adaptation and dispersal on species richness in plant communities under global warming. We find that there is a larger decline in global species richness when interspecific competition is strong. Furthermore, there is a three-way interaction between interspecific competition, evolution and dispersal that creates a complex pattern of biodiversity responses, in which both evolution and dispersal can either increase or decrease the magnitude of species loss. This interaction arises for at least two reasons: 1) different levels of dispersal, evolution and competition creates differences in local and global community structure before climate change, and 2) competitive interactions determine whether the benefits of dispersal and/or evolution (climate tracking and adaptation) outweighs the risks (competitive exclusion).

  • 12.
    Ericsson, Maria
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Jensen, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Domestication and ontogeny effects on the stress response inyoung chickens (Gallus gallus)2016In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, article id 6_35818Article in journal (Refereed)
    Abstract [en]

    Domestication is thought to increase stress tolerance. The connection between stressor exposure,glucocorticoids and behavioural responses has been studied in adults, where domestication effectsare evident. Early stress exposure may induce detrimental effects both in short-and long term.Previous research has reported a lack of glucocorticoid response in newly hatched chickens (Gallusgallus), whereas others have found opposite results. Hence it remains unclear whether the HPA-axis isfunctional from hatch, and if domestication has affected the early post-hatch ontogeny of the stressresponse. Our aims were to investigate the early ontogeny of the HPA-axis and characterize behaviouraland hormonal stress responses in ancestral Red Junglefowl and in two domestic layer strains. Plasmacorticosteone and behavioural responses before and after physical restraint was measured on dayone, nine, 16 and 23 post hatch. The results showed significant increases of corticosterone after stressin all three breeds at all the different ages. The HPA-response decreased with age and was lower inRed Junglefowl. Behavioural responses also decreased with age, and tended to be stronger in RedJunglefowl. In summary, the HPA-axis is reactive from day one, and domestication may have affectedits development and reactivity, alongside with related behaviour responses.

  • 13.
    Eriksson, Viktor
    Linköping University, Department of Physics, Chemistry and Biology.
    Lämpliga stampopulationer av mellanspett (Dendrocopos medius) för återintroduktion i Linköping, Östergötland2019Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The middle spotted woodpecker (Dendrocopos medius) became extinct in Sweden in 1982. The last population inhabited a fragmented area of 300 km2 and were for a long time a characteristic species for the oak stands of Sturefors and Bjärka­Säby, south of Linköping. The reason why the species got extinct depends mostly on habitat fragmentation. Also, the extinction got hasten by harsh wintering conditions. The purpose of this study is to evaluate which of current populations of Dendrocopos medius could best serve as source of founders for a possible reintroduction of the species in Linköping. Populations from Poland, Germany, Latvia and Lithuania were considered, taking their ecology, phylogeny and genetic diversity into account. The population’s abiotic conditions, in combination with their ability to adapt to different habitat was also considered crucial to conduce a successful reintroduction of middle spotted woodpecker in Linköping. Populations from Bialowieza and Krotoszyn in Poland, Wolfsburg in Germany and Kaunas and Marijampole in Lithuania were considered most suitable to contribute with founders. Since the middle spotted woodpecker could work as a flagship species for old and open oak stands, a reintroduction of the species could turn up the awareness for nature conservation, species conservation and biodiversity. 

  • 14.
    Fors, Filip
    Linköping University, Department of Physics, Chemistry and Biology.
    A Versatile Group of Molecules, Can Defensins Make an Impact in Medicine?2019Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Antimicrobial peptides are an ancient form of innate defense and is present in all ways of life. In humans they are present as cathelicidins and defensins. Both are important for the immune system and they exhibit activity against viruses, bacteria and fungi. Defensins exhibit less cytotoxicity and are better characterized and are thus more easily developed as therapeutic tools. Defensins are apt at doing a multitude of things, from inhibiting Herpes simplex virus replication and preventing anthrax’ lethality to helping with wound closure and acting as biomarkers for a variety of ailments. Defensins have consistently shown good results in a laboratory setting but have less than exemplary in vivo results. Defensins’ multifunctionality as well as the complex environment in living organisms makes characterizing why defensins are not performing as well in vivo difficult. They can also exhibit negative side-effects such as increasing the infectivity of the HIV and inhibiting anti-viral molecules of the innate immune system. Nevertheless, they exhibit big potential as complementary drugs, adjuvants, biomarkers, wound treatment and much more. Further characterization and development is absolutely necessary in these times of increasing antibiotic resistance. 

  • 15.
    Gasparini, Isabella
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Cardiorespiratory responses upon increased metabolism in the Ornate Tinamou, Nothoprocta ornata2012Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    The Bolivian Ornate Tinamou, Nothoprocta ornata, lives higher than 3300 m above sea level and must constantly deal with a restricted availability of atmospheric oxygen, i.e., chronic hypoxia. Interestingly enough, the Ornate Tinamou has a small heart to body ratio, which implies a reduced ability in transporting oxygenated blood to the tissues. In order to increase knowledge about the cardiorespiratory response of the Ornate Tinamou, heart rate (HR) and ventilation frequency (VR) were monitored during resting at 25 °C. The values were compared with those obtained in conditions known to elevate metabolism, i.e., lowered temperature and graded exercise. This was later compared with domestic chickens, Gallus gallus. Results showed a significant increase in HR at 4 °C, 305 ±42 bpm in the Ornate Tinamou when compared with HR at 25°C, 241± 48 bpm (330 ±42bpm and 239 ±32bpm in chicken). A significant increase in VR was only observed in chicken. As expected, with a progressive increase in running speed, a significant increase in HR in both species was observed. At 1,5 km h-1, HR in the Ornate Tinamou was 327 ±5,6 bpm and 342 ±8,5 in chicken. At 3,0 km h -1 HR was 383 ±15 bpm and 404 ±7,9, respectively. However, HR was not significantly higher in the Ornate Tinamou than in chicken, indicating that there must be other physiological adaptations involved in the sufficient oxygen delivery to tissues, e.g. a high blood oxygen affinity or a preference for anaerobic metabolism due to living in a chronic hypoxic environment.

  • 16.
    Gustavsson, Frida
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Validation study: HemoCue Hb 201 + as a tool in comparative physiological field studies on avian blood2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Haemoglobin concentration is becoming a widely popular parameter to use to assess physiological condition within a broad range of species. Assessments of large populations would preferable be done in field to receive quick results and avoid confounding factors associated with transport of blood. A validation study is here performed to see how well the point-of-care device HemoCue Hb 201 + can assess haemoglobin concentration on avian blood. Nucleated erythrocytes have previously been pointed out as something that makes it problematic to apply HemoCue Hb 201 +, designed for human blood, on avian blood. Here it is shown that HemoCue Hb 201 + accurately can estimate haemoglobin concentration for chicken-, tinamou-, and ostrich blood. However, manipulation of ostrich cells, to yield a larger mean corspuscular volume, results in HemoCue Hb 201 + overestimating haemoglobin concentration. A large mean corpuscular volume could therefore be something that impair accuracy in values retrieved with HemoCue Hb 201 +. This study shows that HemoCue Hb 201 + seems possible to apply on avian blood to some extent, but highlights the importance of validation studies when applying this device on new species. 

  • 17.
    Hana, Kuci
    Linköping University, Department of Thematic Studies.
    Enzymatic hydrolysis of brown macroalgae for biogas fuel production2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Macroalgae, so-called seaweeds, represent an innovative and sustainable substrate for biogas fuels production (third generation’s biofuels). However, large scale implementation are not yet commercialized due to high biomass production costs and in addition, low biomethane yields observed within some algae species preventing high energy conversion efficiency. The aim with this study was to investigate the impact of the enzymatic hydrolysis pre-treatment on the AD of macroalgae. Five brown macroalgae, A. nodosum and F. vesiculosus grown nearshore and A. esculenta, L. digitata and S. latissima grow offshore, were pre-treated with four different enzymes at 37 oC for 24 h. The biomethane yield was determined by anaerobic batch digestion test. The enzymatic pre-treatment improved the hydrolysis, where the biomethane yield of near- and offshore macroalgae was enhanced between 70 to 82 % and 12 to 48 %, respectively, compared with un-treated biomass. In addition the work present an economic analysis on the pre-treatment applied to a hypothetical full scale AD for biogas fuel production testing L. digitata and A. nodosum. Two cases presented, case 0 is based from the cultivation, harvesting and enzyme cost from literature and in case 1 the cultivation and enzyme cost reduced by 75 and 90 %, respectively. Reducing the cultivation and enzyme cost by 75 and 90 %, respectively, had a positive influence on the economy of the hypothetical large scale biogas plant. 

    The full text will be freely available from 2027-09-30 11:13
  • 18.
    Hasler, Berit
    et al.
    Department of Environmental Science, Aarhus University, Aarhus, Denmark.
    Hyytiäinen, Kari
    Faculty of Agriculture and Forestry, University of Helsinki ,Helsinki, Finland.
    Refsgaard, Jens Christian
    Department of Hydrology, Geological Survey of Denmark and Greenland, Copenhagen, Denmark.
    Smart, James C. R.
    School of Environment and Science and the Australian Rivers Institute at Griffith University, Brisban, Australia.
    Tonderski, Karin
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Sustainable ecosystem governance under changing climate and land use: An introduction2019In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, p. 1-5Article in journal (Refereed)
    Abstract [en]

    Combatting eutrophication is currently a major challenge for policy makers in the Baltic Sea region, and it is likely to remain so in the decades to come. Although total nutrient loads to the Baltic Sea have recently declined, the gap between current loadings and those required to ensure the desired status is still substantial (Reusch et al. 2018). This Special Issue is dedicated to research that helps inform how the eutrophication challenge might best be addressed by improving our understanding of technological constraints, societal drivers of change, land uses, environmental policies, and innovative governance with stakeholder involvement. These issues are important for the current generation and those to come and are issues we must address in order to succeed in reducing nutrient loads to the desired levels to gradually achieve the desired good environmental status of the Baltic Sea. Currently, we witness a new era of water policies across the entire Baltic Sea region. Our changing climate is impacting on precipitation and runoff, and is also the reason why new EU climate policies seek to tie carbon sinks more visibly to carbon sources. Both these aspects have repercussions for water policies. Thus, solving eutrophication challenges requires sharpening of existing policies and instruments, as well as creating new insights and governance approaches with broad stakeholder involvement in a changing environment. In order to design coherent water and climate policies, and target and implement those policies more efficiently, policy makers need to combine new insights regarding the inhabitants in the region, the catchments, and the Baltic Sea itself. Such insights can be expected from soil scientists, agronomists, hydrogeologists, marine ecologists, economists, and social and policy scientists. What is needed is on the one hand effectively targeted governance at appropriate spatial and temporal scales, adapted to differing interests and motivations of citizens living around the Baltic Sea, and on the other hand fine tuning and co-designing of policies at local, national, Baltic Sea regional and EU level. This Special Issue brings together recent research from four BONUS-funded projects—BONUS BALTICAPP, BONUS GO4BALTIC, BONUS MIRACLE and BONUS SOILS2SEA—that comprised part of the ‘Viable Ecosystem’ and ‘Sustainable Ecosystem Services’ BONUS research programmes. The projects addressed these common concerns through somewhat different, but inter-related, themes. Key messages emphasized and discussed in the research papers of this Special Issue are summarized under four interlinked themes: Scenarios for the future, Policies and ecosystem services in water governance, Novel approaches for managing nutrients, and Advanced modelling from field level to the entire Baltic Sea region.

  • 19.
    Herberthson, Magnus
    et al.
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Johansson, KarinLinköping University, Department of Mathematics. Linköping University, Faculty of Science & Engineering.Kozlov, VladimirLinköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.Ljungkvist, EmmaLinköping University, National Supercomputer Centre (NSC).Singull, MartinLinköping University, Department of Mathematics, Mathematical Statistics . Linköping University, Faculty of Science & Engineering.
    Proceedings from Workshop: Mathematics in Biology and Medicine, 11-12 May 2017, Linköping University2017Conference proceedings (editor) (Refereed)
  • 20.
    Hägg, Sara
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Computational Biology . Linköping University, The Institute of Technology.
    Alserius, Thomas
    Department of Cardiothoracic Surgery and Anaesthesiology and Department of Molecular Medicine and Surgery, Karolinska University Hospital Solna, Karolinska Institutet, Stockholm, Sweden.
    Noori, Peri
    Computational Medicine Group (www.CompMed.se), Center for Molecular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden.
    Skogsberg, Josefin
    Computational Medicine Group (www.CompMed.se), Center for Molecular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden.
    Ruusalepp, Arno
    Department of Thoracic Surgery, Tartu University Hospital, Tartu, Estonia.
    Ivert, Torbjörn
    Department of Cardiothoracic Surgery and Anaesthesiology and Department of Molecular Medicine and Surgery, Karolinska University Hospital Solna, Karolinska Institutet, Stockholm, Sweden.
    Tegnér, Jesper
    Linköping University, Department of Physics, Chemistry and Biology, Computational Biology . Linköping University, The Institute of Technology.
    Björkegren, Johan
    Computational Medicine Group (www.CompMed.se), Center for Molecular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden.
    Dual-Specificity Phosphatase-1—An Anti-Inflammatory Marker in Blood Independently Predicting Prolonged Postoperative Stay after Coronary Artery Bypass Grafting: DUSP1 – A Preoperative Blood Marker of Postoperative StayManuscript (preprint) (Other academic)
    Abstract [en]

    Objectives: Perform multi-organ expression profiling to identify gene markers predicting postoperative complications and hospitalization after coronary artery by-pass grafting (CABG) surgery.

    Background: Identifying patients who are at increased risk of morbidity and prolonged post-operative stay is of interest from both health-economic and individual patient perspectives. Patients with diabetes often present with inflammatory conditions and have prolonged hospitalization after CABG. The recent development of technologies to generate high-dimensional data provides an opportunity to identify preoperative markers that can be used to help optimize preoperative planning to minimize postoperative complications.

    Methods: We analyzed 198 whole-genome expression profiles of liver, skeletal muscle, and visceral fat isolated from 66 patients undergoing CABG in the Stockholm Atherosclerosis Gene Expression (STAGE) study. The findings were validated in pre-operative blood samples isolated from 181 patients undergoing CABG at Tartu University Hospital.

    Results: As shown in other studies, diabetic CABG patients in the STAGE cohort also had prolonged hospitalization time (P<0.02). Out of ~50 000 mRNAs measures in the liver, skeletal muscle and visceral fat in 66 STAGE patients, the mRNA levels of anti-inflammatory gene dual specificity phosphatase-1 (DUSP1) correlated independently with post-operative rehabilitation and separated the patients into those with normal (8 days) and prolonged hospitalization (>8 days). In the validation cohort, preoperative blood levels of DUSP1 separated patients with short and long hospitalization stay (P=9x10-10).

    Conclusions: From genome scans in three separate organs, we identified the anti-inflammatory gene DUSP1 as a pre-operative marker indicating risk for prolonged postoperative stay after CABG.

  • 21.
    Hägg, Sara
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Computational Biology . Linköping University, The Institute of Technology.
    Salehpour, Mehran
    Ion Physics, Angström Laboratory, Department of Engineering Sciences, Uppsala University, Uppsala, Sweden.
    Noori, Peri
    From the Computational Medicine Group, Center for Molecular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden.
    Lundström, Jesper
    From the Computational Medicine Group, Center for Molecular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden.
    Skogsberg, Josefin
    From the Computational Medicine Group, Center for Molecular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden.
    Konrad, Peter
    Department of Surgery, Stockholm Söder Hospital, Karolinska Institutet, Stockholm, Sweden.
    Rosfors, Stefan
    Department of Clinical Physiology, Stockholm Söder Hospital, Karolinska Institutet, Stockholm, Sweden.
    Tegnér, Jesper
    Linköping University, Department of Physics, Chemistry and Biology, Computational Biology .
    Björkegren, Johan
    From the Computational Medicine Group, Center for Molecular Medicine, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Sweden.
    Carbon-14 Dating to Determine Carotid Plaque Age: Carbon-14 Dating of Carotid PlaquesManuscript (preprint) (Other academic)
    Abstract [en]

    Rationale: The exact nature of atherosclerotic plaque development and the molecular mechanisms that lead to clinical manifestations of carotid stenosis are unclear. After nuclear bomb tests in the 1950s, atmospheric 14C concentrations rapidly increased. Since then, the concentrations have been declining, and the curve of declination can be used to date biological samples synthesized during the last five to six decades.

    Objective: To investigate plaque age as a novel characteristic of atherosclerotic plaques in patients with carotid stenosis.

    Methods and Results: Carotid plaques from 29 well-characterized endarterectomy patients with symptomatic carotid stenosis were analyzed by accelerator mass spectrometry, and global gene expression of 25 plaque samples was profiled with HG-U133 Plus 2.0 arrays. The average plaque age was 9.3 years, and inter- and intrasample standard variations were low (1–3.5 years); thus, most of the plaques were generated 5–15 years before surgery. Plaque age was not associated with patient age or plaque size, determined by intima-media thickness, but was inversely related to plasma insulin levels (P=0.0014). A cluster of functionally related genes enriched with genes involved in immune responses was activated in plaques with low plaque age, as were oxidative phosphorylation genes.

    Conclusion: Patients with mild insulin resistance have increased immune and inflammatory gene activity in their carotid plaques causing them to become instable, rapidly progressing into clinical manifestations at a relatively young age. These results show that plaque age, determined by 14C dating, is a novel and important characteristic of atherosclerotic plaques that will improve our understanding of the clinical significance and molecular underpinnings of atherosclerosis.

  • 22.
    Ingberg, Edvin
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Chemistry.
    Ström, Jakob
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry. veÖrebro University Hospital, Sweden; Unirsity of Örebro, Sweden.
    Effects of high and low 17 beta-estradiol doses on focal cerebral ischemia in rats2016In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, no 20228Article in journal (Refereed)
    Abstract [en]

    The majority of the numerous animal studies of the effects of estrogens on cerebral ischemia have reported neuroprotective results, but a few have shown increased damage. Differences in hormone administration methods, resulting in highly different 17 beta-estradiol levels, may explain the discrepancies in previously reported effects. The objective of the present study was to test the hypothesis that it is the delivered dose per se, and not the route and method of administration, that determines the effect, and that high doses are damaging while lower doses are protective. One hundred and twenty ovariectomized female Wistar rats (n = 40 per group) were randomized into three groups, subcutaneously administered different doses of 17 beta-estradiol and subjected to transient middle cerebral artery occlusion. The modified sticky tape test was performed after 24 h and the rats were subsequently sacrificed for infarct size measurements. In contrast to our hypothesis, a significant negative correlation between 17 beta-estradiol dose and infarct size was found (p = 0.018). Thus, no support was found for the hypothesis that 17 beta-estradiol can be both neuroprotective and neurotoxic merely depending on dose. In fact, on the contrary, the findings indicate that the higher the dose of 17 beta-estradiol, the smaller the infarct.

  • 23.
    Jakobsson, Tell
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Microbiology. Linköping University, Faculty of Health Sciences.
    Forsum, Urban
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Microbiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Microbiology.
    Changes in the predominant human Lactobacillus flora during in vitro fertilisation2008In: Annals of Clinical Microbiology and Antimicrobials, ISSN 1476-0711, E-ISSN 1476-0711, Vol. 7, article id 14Article in journal (Refereed)
    Abstract [en]

    Background: Signature matching of nucleotide sequences in the V1 and V3 regions 16S rRNA genes using pyrosequencing technology is a powerful tool for typing vaginal Lactobacilli to the species level and has been used for investigating the vaginal microbial niche. Methods: This study has characterized the normal cultivable vaginal Lactobacillus flora at varying estradiol levels in plasma, the study comprised 17 patients undergoing ovarian stimulation for In Vitro Fertilization (IVF) treatment. The vaginal status of each participant was initially assessed as normal according to Amsel and Nugent criteria. Results: L. crispatus, L. gasseri and/or L. jensenii were present in 10of the patients throughout the study period, and little variation among these three species was encountered in individual patients. The flora of three women was dominated by L. delbrüeckii, L. rhamnosus or L. vaginalis. One woman exhibited a dominance of L. iners. The flora of the remaining three women were initially dominated by L. rhamnosus or L. reuteri, but as their estrogen levels rose, their flora composition altered, to become dominated by one of the three species most common in a normal, healthy vagina. Conclusion: Signature matching of nucleotide sequences in the V1 and V3 regions of 16S rRNA genes is a discriminative tool for the study of vaginal Lactobacilli and can be used to track the Lactobacillus flora under a variety of physiological conditions. © 2008 Jakobsson and Forsum, licensee BioMed Central Ltd.

  • 24.
    Johannesson, Karin M.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Lindström, G.
    Swedish Meteorological and Hydrological Institute, SMHI.
    Heeb, A.
    Swedish Board of Agriculture (Jordbruksverket).
    Milver, A.
    Gothenburg University.
    Rönnberg, R.
    Stockholm Vatten, Sweden.
    Sundblad-Tonderski, Karin
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Andersson, L.
    Swedish Meteorological and Hydrological Institute, SMHI.
    Can spatial and temporal nutrient concentration variability be captured by catchment agro-geographical characteristics and water quality modelling?2015Manuscript (preprint) (Other academic)
    Abstract [en]

    In water management, source areas need to be identified and seasonal variability of nutrient flows assessed to facilitate design of cost-efficient mitigation programs. This study aimed at investigating to what degree sub-catchment spatial and temporal nutrient concentration variability could be captured by their agro-geographical characteristics and water quality modelling.

    An agricultural catchment (160 km2) in Southeast Sweden was investigated with respect to source areas for phosphorus (P), nitrogen and particle losses. The specific aims were to 1) investigate the spatial variability of nutrient and particle concentrations and transport from different sub-catchments, 2) analyze if sub-catchment characteristics could explain differences in nutrient and particle concentration dynamics and overall nutrient losses, and 3) evaluate how well monitored temporal and spatial variability in nutrient concentrations could be simulated by a catchment model (HYPE). The purpose with the latter was to find recommendations for further model development and identify limitations for the use of catchment models in local water management.

    Water flow was measured in two stations during 2009-2011. Grab samples were collected in synoptic sampling campaigns covering 10 sampling points during periods that represented various water flow regimes. Water samples were analyzed for total P (TP), dissolved phosphate (PO4-P), nitrate (NO3-N) and suspended matter (SUSP). The HYPE model was setup with the same detailed agro-geographical data as used for the statistical analyses of spatial and temporal correlations. The results showed that the sub-catchment variability of all measured nutrient concentrations were correlated with agro-geographical characteristics. All fractions of P concentrations were strongly correlated with soil type, whereas NO3-N concentrations were more related to crop factors. With regard to temporal dynamics of monitored concentrations, links to seasonality and water flow were more significant for NO3-N than for TP. Concentrations generated from the water quality model (HYPE) did not capture the subcatchment or temporal variability indicated from monitoring, particularly not for P concentrations. Neither did the modelled correlation between agro-geographical factors and concentrations correspond to that found for monitored concentrations. Some suggestions for model improvement were identified. Although water quality models are useful for local water management when it comes to modelling the impact of e.g. measures or climate change, our results suggest that their value might still be more limited when assessing variability on the subcatchment scale.

  • 25.
    Johannesson, Karin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, The Institute of Technology.
    Tonderski, Karin S.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Ehde, Per Magnus
    Wetland Research Centre, Halmstad University, Sweden.
    Weisner, Stefan E.B.
    Wetland Research Centre, Halmstad University, Sweden.
    Temporal phosphorus dynamics affecting retention estimates in agricultural constructed wetlands2017In: Ecological Engineering: The Journal of Ecotechnology, ISSN 0925-8574, E-ISSN 1872-6992, Vol. 103, p. 436-445Article in journal (Refereed)
    Abstract [en]

    Data from seven constructed wetlands (CWs) in the south of Sweden were analyzed to investigate the effects of water flow and season on inflow phosphorus (P) concentrations and temporal P retention variations in CWs receiving runoff from arable land. The form of P (dissolved or particulate) during different water flows (high and low) and seasons (warm and cold) was investigated using the results of total P (TP) and phosphate analyzed in grab samples that had been collected regularly or occasionally during two to nine years, along with continuous water flow measurements.

    The form of inflow and outflow P (particulate or dissolved P) differed between CWs, and also varied with season and flow. For instance, in three of the CWs, particulate P (PP) dominated the inflow during the cold period with high flow, while during the other periods the proportion of PP was approximately 50%. In one CW situated in a catchment with high clay content, PP dominated both inflow and outflow at all times. The average clay content in catchment top soils was positively correlated to the flow-weighted inflow TP concentrations.

    In three CWs receiving runoff through drainage pipes, the relationship between TP concentrations (TPin) and water flow was positive, both during high and low flow, and during warm and cold period. However, in four CWs that received surface water runoff, the relationship between TPin and water flow was positive during high flow periods (i.e. the 25% sampling occasions with the highest flow), and during low flow and warm period, the relationship was negative in these four wetlands, indicating either anoxic stagnant water upstream or influence from rural wastewater.

    The temporal dynamics of P concentrations mean that in some of the CWs, the main part of the annual P retention may occur during a few days with high water flows. The correlation between concentration and water flow suggests that the water sampling strategy may have a considerable impact on retention estimates, as exemplified by some calculation examples.

  • 26.
    Karlsson, Anna-Carin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Fallahshahroudi, Amir
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Johnsen, Hanna
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Hagenblad, Jenny
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Wright, Dominic
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Andersson, Leif
    Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden.
    Jensen, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    The effect of a domestication related mutation in the thyroid stimulating hormone receptor (TSHR) on photoperiodic response and reproduction in chickenManuscript (preprint) (Other academic)
    Abstract [en]

    The thyroid stimulating hormone receptor (TSHR) has been suggested to be a “domestication locus” in the chicken. A strong selective sweep over the gene in domestic breeds of chicken, but not in the ancestral Red Junglefowl, and significant effects of a mutation in TSHR on domestication related traits in chicken, indicate that the gene has been important for the chicken domestication. The TSHR play a key role in the signal transduction of seasonal reproduction, which is characteristically less strict in domestic animals. We investigated the effect of the mutation on reproductive traits as well as TSHB, TSHR, DIO2 and DIO3 gene expression during altered day length (photoperiod) in females and males intercross chickens homozygous for the mutation (d/d) or wild type homozygotes (w/w). This allowed an assessment of the effect of genotype at this locus against a random mix of RJF and WL genotypes throughout the rest of the genome. The TSHR gene expression was significantly lower in both d/d females and males, in comparison to w/w individuals, indicating a strong effect of the “domestic” mutation on gene expression. The d/d females showed a faster increase in the onset of laying than w/w females, and d/d males showed a reduced response to altered day length in testicular size and significant lower levels of TSHB and DIO3 expression, in comparison to w/w males. Additionally, pure White Leghorn females kept under natural day length in Sweden during December showed active ovaries and significant lower levels of TSHR and DIO3 expression in comparison to Red Junglefowl females kept under similar conditions. Our study suggest that the TSHR mutation affects photoperiodic response in chicken in the direction of being less dependent on seasonal reproduction, a typical domestication feature, and may therefore have been important for the chicken domestication.

  • 27.
    Kozlov, Vladimir
    et al.
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Tkachev, Vladimir
    Linköping University, Department of Mathematics, Mathematics and Applied Mathematics. Linköping University, Faculty of Science & Engineering.
    Vakulenko, Sergey
    St. Petersburg National Research University of Information Technologies, Saint Petersburg, Russia.
    Wennergren, Uno
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering.
    Global stability and persistence of complex foodwebs2019In: Annali di Matematica Pura ed Applicata, ISSN 0373-3114, E-ISSN 1618-1891, Vol. 198, no 5, p. 1693-1709Article in journal (Refereed)
    Abstract [en]

    We develop a novel approach to study the global behaviour of large foodwebs for ecosystems where several species share multiple resources. The model extends and generalizes some previous works and takes into account self-limitation. Under certain explicit conditions, we establish the global convergence and persistence of solutions.

  • 28.
    Kuruvilla, Jacob
    Linköping University, Department of Physics, Chemistry and Biology.
    Localization, functional analysis and physiological role of Anion Transporter 3 (Arabidopsis Thaliana)2009Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    In this project, the maintenance of dynamic cycling of inorganic phosphate is discussed in terms of a phosphate transporter, ANTR3. Reverse genetics are applied with the help of bioinformatics and other web based tools which provided valuable initial information. The model organism Arabidopsis thaliana, both wild-type and mutants was cultivated hydroponically. Screening for homozygotes proceeded standardization of a protocol for isolation of plastids from the roots of these plants. Presence and absence of protein in root plastids was confirmed by western blotting in wild-type and mutants respectively. This was followed by functional and biochemical analysis of the protein by transport experiments using radioactively tagged phosphate.

    The development of a protocol for isolation of root plastids from roots of Arabidopsis thaliana with high yields has been successful. In-vitro studies by radioactive phosphate transport experiments were possible with the help of knock out mutants. It has been concluded that transport of Pi via ANTR3 is dependent either on an H+ or a Na+ gradient. Back exchange experiments have aided us in establishing its activity in export and import of Pi. Last but not the least, phenotypic analysis have observed larger biomass in mutants leading to the conclusion that even though other transporters are present the sink (roots) – source (leaves) balance is disturbed.

  • 29.
    Kynkäänniemi, P.
    et al.
    Department of Soil and Environment, Swedish University of Agricultural Sciences.
    Johannesson, Karin M.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Ulén, B.
    Department of Soil and Environment, Swedish University of Agricultural Sciences.
    Sundblad-Tonderski, Karin
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Assessment of particle deposition and accumulation in newly constructed wetlands receiving agricultural runoff2015Manuscript (preprint) (Other academic)
    Abstract [en]

    This study analysed variations in sediment deposition and accumulation to improve understanding of retention processes in small wetlands constructed on clay soils. Sediment deposition (in traps) and accumulation (on plates) was measured in four wetlands in east-central Sweden.

    Particle deposition generally exceeded (up to eight-fold) the total particle load to the wetlands, especially in the spring-summer period, suggesting that the settled particles in the traps were generated from internal processes. The particles probably originated from erosion of the bottom and sides of the wetlands, or from production of organic material which deposited in the traps.

    Particle resuspension was evident in all wetlands and considered an important process. Only 13-23% of the deposited material in the traps remained on the plates in the wetlands. Both particle deposition and accumulation was very low in one wetland receiving high hydraulic load (HL, 400 m yr-1), suggesting that such high-loaded wetlands are not efficient as particle sinks in clay soil areas. In the other wetlands, more than 80% of the total sediment accumulation occurred in the initial parts of the wetlands (which represented the first 20% of the total wetland area), indicating the importance of designing wetlands with an initial wetland section that is easy accessed for sediment removal as maintenance.

    The results from this study point to the importance of internal processes and resuspension for annual particle accumulation in constructed wetlands.

  • 30.
    Lees, John
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Lindholm, Caroline
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Batakis, Petros
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Busscher, M.
    Wageningen University, Netherlands.
    Altimiras, Jordi
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    The physiological and neuroendocrine correlates of hunger in the Red Junglefowl (Gallus gallus)2017In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 7, article id 17984Article in journal (Refereed)
    Abstract [en]

    The ability to regulate food intake is critical to survival. The hypothalamus is central to this regulation, integrating peripheral signals of energy availability. Although our understanding of hunger in rodents is advanced, an equivalent understanding in birds is lacking. In particular, the relationship between peripheral energy indices and hypothalamic hunger peptides, agouti-related protein (AgRP), proopiomelanocortin (POMC) and neuropeptide Y (NPY) is poorly understood. Here, we compare AgRP, POMC and NPY RNA levels in the hypothalamus of Red Junglefowl chicks raised under ad libitum, chronic restriction and intermittent feeding regimens. Hypothalamic gene expression differed between chronically and intermittently restricted birds, confirming that different restriction regimens elicit different patterns of hunger. By assessing the relationship between hypothalamic gene expression and carcass traits, we show for the first time in birds that AgRP and POMC are responsive to fat-related measures and therefore represent long-term energy status. Chronically restricted birds, having lower indices of fat, show elevated hunger according to AgRP and POMC. NPY was elevated in intermittently fasted birds during fasting, suggesting a role as a short-term index of hunger. The different physiological and neuroendocrine responses to quantitative versus temporal feed restriction provide novel insights into the divergent roles of avian hunger neuropeptides.

  • 31.
    Lerner, Henrik
    Linköping University, Department of Culture and Communication, Arts and Humanities. Linköping University, Faculty of Arts and Sciences.
    Vilka konsekvenser av en forskningsintervju bör man förutsäga?2010In: Gäller vanligt folkvett också för akademiker?: Rapport från ett seminarium om makt och etik. / [ed] Gustav Bockgård och Håkan Tunón, Uppsala: Centrum för biologisk mångfald , 2010, p. 44-47Chapter in book (Other academic)
  • 32.
    Lerner, Henrik
    et al.
    Linköping University, Department of Culture and Communication, Centre for Applied Ethics. Linköping University, Faculty of Arts and Sciences.
    Tunón, Håkan
    Sveriges lantbruksuniversitet, Centrum för biologisk mångfald .
    Vad är traditionell och lokal kunskap?2010In: Nycklar till kunskap.: Om människans bruk av naturen. / [ed] Håkan Tunón och Anna Dahlström, Uppsala: Centrum för biologisk mångfald , 2010, p. 41-57Chapter in book (Other academic)
    Abstract [sv]

    Nycklar till kunskap om människans bruk av naturen är en antologi med ett trettiotal uppsatser som beskriver hur man kan arbeta med olika typer av källor för att nå insikt om hur människan brukar och har brukat naturen och dess resurser. Uppsatserna är skrivna av specialister inom en mängd skilda ämnen och beskriver bland annat hur man arbetar med bilder, biologiskt kulturarv, bondedagböcker, dendrokronologi, djupintervjuer, etnokartering, folkminnesmaterial, tryckt litteratur, föremålsrekonstruktion, kol-14-datering, lantmäterikartor, makrofossil, osteologi och pollenanalys.

    Vårt äldre naturutnyttjande spelar roll för vilket landskap och vilken biologisk mångfald vi har både idag och i framtiden. I alla tider har människan nyttjat landskapets biologiska resurser för olika ändamål. Detta användande har utvecklats eller förändrats under historien, och mycket av det äldre har också fallit i glömska. Men kunskap om traditionellt nyttjande har inte bara en kulturhistorisk betydelse utan kan även komma att vara väsenligt för framtiden.

    Att rättvisande beskriva hur vi förr har använt en särskild biologisk resurs kan ibland vara en komplicerad uppgift, men det finns en mängd olika källor som var och en kan bidra med pusselbitar. Ofta behövs en tvärvetenskaplig ansats för att få helhetsbilden. Tanken med denna bok är att ge en introduktion till hur man kan gå tillväga när man arbetar med olika typer av källmaterial för att skapa sig en mer rättvisande bild och att skapa ett möte mellan olika discipliner.

    Boken kan fungera som en lärobok för studenter inom flera olika ämnen vid universitet, högskolor samt för fritidsforskare, men också som en inspiration till tvärvetenskapliga samarbeten mellan forskare från olika ämnesområden. Kunskap om vårt historiska nyttjande av naturen utgör inte bara historisk kuriosa, utan kan även spela en viktig roll inom naturvård och långsiktigt hållbart nyttjande av biologiska resurser.

  • 33.
    Li, Jiyun
    et al.
    China Agr Univ, Peoples R China; Hunan Agr Univ, Peoples R China.
    Bi, Zhenwang
    Shandong Acad Clin Med, Peoples R China.
    Ma, Shizhen
    China Agr Univ, Peoples R China.
    Chen, Baoli
    Shandong Ctr Dis Control and Prevent, Peoples R China.
    Cai, Chang
    Zhejiang Agr and Forestry Univ, Peoples R China; Murdoch Univ, Australia.
    He, Junjia
    China Agr Univ, Peoples R China.
    Schwarz, Stefan
    China Agr Univ, Peoples R China; Free Univ Berlin, Germany.
    Sun, Chengtao
    China Agr Univ, Peoples R China.
    Zhou, Yuqing
    China Agr Univ, Peoples R China.
    Yin, Jia
    Shandong Univ, Peoples R China; Shandong Univ, Peoples R China.
    Hulth, Anette
    Karolinska Inst, Sweden; Publ Hlth Agcy Sweden, Sweden.
    Wang, Yongqiang
    China Agr Univ, Peoples R China.
    Shen, Zhangqi
    China Agr Univ, Peoples R China.
    Wang, Shaolin
    China Agr Univ, Peoples R China.
    Wu, Congming
    China Agr Univ, Peoples R China.
    Nilsson, Lennart E
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology, Infection and Inflammation. Linköping University, Faculty of Medicine and Health Sciences.
    Walsh, Timothy R.
    China Agr Univ, Peoples R China; Cardiff Univ, Wales.
    Börjesson, Stefan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology, Infection and Inflammation. Linköping University, Faculty of Medicine and Health Sciences. Natl Vet Inst SVA, Sweden.
    Shen, Jianzhong
    China Agr Univ, Peoples R China.
    Sun, Qiang
    Shandong Univ, Peoples R China.
    Wang, Yang
    China Agr Univ, Peoples R China.
    Inter-host Transmission of Carbapenemase-Producing Escherichia coli among Humans and Backyard Animals2019In: Journal of Environmental Health Perspectives, ISSN 0091-6765, E-ISSN 1552-9924, Vol. 127, no 10, article id 107009Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The rapidly increasing dissemination of carbapenem-resistant Enterobacteriaceae (CRE) in both humans and animals poses a global threat to public health. However, the transmission of CRE between humans and animals has not yet been well studied. OBJECTIVES: We investigated the prevalence, risk factors, and drivers of CRE transmission between humans and their backyard animals in rural China. METHODS: We conducted a comprehensive sampling strategy in 12 villages in Shandong, China. Using the household [residents and their backyard animals (farm and companion animals)] as a single surveillance unit, we assessed the prevalence of CRE at the household level and examined the factors associated with CRE carriage through a detailed questionnaire. Genetic relationships among human- and animal-derived CRE were assessed using whole-genome sequencing-based molecular methods. RESULTS: A total of 88 New Delhi metallo-beta-lactamases-type carbapenem-resistant Escherichia coli (NDM-EC), including 17 from humans, 44 from pigs, 12 from chickens, 1 from cattle, and 2 from dogs, were isolated from 65 of the 746 households examined. The remaining 12 NDM-EC were from flies in the immediate backyard environment. The NDM-EC colonization in households was significantly associated with a) the number of species of backyard animals raised/kept in the same household, and b) the use of human and/or animal feces as fertilizer. Discriminant analysis of principal components (DAPC) revealed that a large proportion of the core genomes of the NDM-EC belonged to strains from hosts other than their own, and several human isolates shared closely related core single-nucleotide polymorphisms and bla(NDM)( )genetic contexts with isolates from backyard animals. CONCLUSIONS: To our knowledge, we are the first to report evidence of direct transmission of NDM-EC between humans and animals. Given the rise of NDM-EC in community and hospital infections, combating NDM-EC transmission in backyard farm systems is needed.

  • 34.
    Løtvedt, Pia Katrine
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Domestication and early experiences in chickens: Behavior, stress and gene expression2017Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    A number of animal species have undergone domestication, the process of becoming adapted to living in captivity and in proximity to humans. Common for these species is that they have all developed certain traits, including changes to coat color, body size and level of fearfulness. This has been termed the domestic phenotype. Among these traits is also an attenuation of the response to stress, both behaviorally and physiologically. Thus, release of glucocorticoids such as cortisol or corticosterone is lower in domesticated species. However, the underlying mechanism for this is not yet well understood. In this thesis, we have investigated genetic mechanisms for the attenuation of the physiological stress response in ancestral chickens, the Red Junglefowl, and domesticated chickens, the White Leghorn.

    We found a number of genes that differed in expression between the two breeds in several tissues involved in the stress response. Among the most interesting findings were lower expression of genes involved in production and secretion of ACTH in the pituitary, and in the production of glucocorticoids in the adrenal glands, in the domesticated White Leghorns. We also found higher expression of the glucocorticoid receptor in White Leghorns, indicating that they may have a more efficient negative feedback of the physiological stress response.

    We then investigated the transcriptome of the chicken pituitary more closely, and we discovered that a number of genes highly involved in several important physiological axes showed differential expression between the ancestral and the domesticated breed. Among these were genes involved in the stress response, the reproductive system, and in metabolism and growth. As these traits are modified in domesticated species, our results suggest that changes to gene expression in the pituitary may be an important underlying factor of the domestic phenotype.

    A separate aim of this thesis was to investigate effects of hatching time in chickens on their subsequent phenotype. Time of hatching constitutes an early experience that may differ between individuals, and we therefore hypothesized that differences in hatching time would affect chickens later in life. While a number of studies have been performed on hatching time and post-hatch growth, very little work has been done on effects on behavior. We found that the time of hatching had sex-specific effects. Hatching times in females were negatively correlated with body weight, whereas in males, behaviors such as reaction to novelty and spatial learning were affected.

    As time of hatching is governed by various hormones, including thyroid hormone and corticosterone, we suggest that changes to the levels of these hormones could affect both hatching time and post-hatch phenotypes. Understanding these mechanisms better would be beneficial in terms of production, where batch homogeneity is important, in research on early experiences and the potential for maternal programming, and in evolutionary questions on trade-off between different life strategies.

    List of papers
    1. Chicken domestication changes expression of stress-related genes in brain, pituitary and adrenals
    Open this publication in new window or tab >>Chicken domestication changes expression of stress-related genes in brain, pituitary and adrenals
    Show others...
    2017 (English)In: Neurobiology of stress, ISSN 2352-2895, Vol. 7, p. 113-121Article in journal (Refereed) Published
    Abstract [en]

    Domesticated species have an attenuated behavioral and physiological stress response compared to their wild counterparts, but the genetic mechanisms underlying this change are not fully understood. We investigated gene expression of a panel of stress response-related genes in five tissues known for their involvement in the stress response: hippocampus, hypothalamus, pituitary, adrenal glands and liver of domesticated White Leghorn chickens and compared it with the wild ancestor of all domesticated breeds, the Red Junglefowl. Gene expression was measured both at baseline and after 45 min of restraint stress. Most of the changes in gene expression related to stress were similar to mammals, with an upregulation of genes such as FKBP5, C-FOS and EGR1 in hippocampus and hypothalamus and StAR, MC2R and TH in adrenal glands. We also found a decrease in the expression of CRHR1 in the pituitary of chickens after stress, which could be involved in negative feedback regulation of the stress response. Furthermore, we observed a downregulation of EGR1 and C-FOS in the pituitary following stress, which could be a potential link between stress and its effects on reproduction and growth in chickens. We also found changes in the expression of important genes between breeds such as GR in the hypothalamus, POMC and PC1 in the pituitary and CYP11A1 and HSD3B2 in the adrenal glands. These results suggest that the domesticated White Leghorn may have a higher capacity for negative feedback of the HPA axis, a lower capacity for synthesis of ACTH in the pituitary and a reduced synthesis rate of corticosterone in the adrenal glands compared to Red Junglefowl. All of these findings could explain the attenuated stress response in the domesticated birds.

    Place, publisher, year, edition, pages
    Elsevier, 2017
    Keywords
    Animal domestication, Chicken, Gene expression, Glucocorticoid receptor, HPA axis, Stress response
    National Category
    Genetics
    Identifiers
    urn:nbn:se:liu:diva-143054 (URN)10.1016/j.ynstr.2017.08.002 (DOI)28879214 (PubMedID)2-s2.0-85028334770 (Scopus ID)
    Available from: 2017-11-17 Created: 2017-11-17 Last updated: 2017-11-30Bibliographically approved
    2. Effects of Hatching Time on Behavior and Weight Development of Chickens
    Open this publication in new window or tab >>Effects of Hatching Time on Behavior and Weight Development of Chickens
    2014 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 7, p. e103040-Article in journal (Refereed) Published
    Abstract [en]

    The length of the embryonic period varies both among and within species and can affect the individual phenotype in many ways, both physiologically and behaviorally. In chickens, the hatch window may last 24-48 hours (up to 10% of the incubation time), and studies have shown that incubation length may affect post-hatch growth and physiology. However, little is known about effects on behavior. We therefore investigated how behavior variation correlates with hatching time in the early life of chickens. We also measured egg weight and egg weight loss in relation to hatching time, as well as post-hatch growth. For females, there was a negative correlation between hatch time and body weight from day 4 and throughout the experiment. For males, such a correlation was only observed when testing all hatched males up until day 10. The birds were exposed to a number of behavioral tests, and a principal components analysis was performed on the variables, resulting in four components. For the largest component, termed "Passivity, a tendency of a difference was found between early and middle male hatchers. Furthermore, a significant difference between early and middle male hatchers was found in the second component, termed "Response to novelty. In a spatial learning test, late hatchers tended to learn slower. The behavior of females was not significantly affected by hatching time in any of these tests. This study is among the first to demonstrate a link between time of hatching and early behavior in a precocial species like the chicken, and may help shedding light on the evolutionary trade-offs between incubation length and post-hatch traits. The results may also be relevant from a perspective of stress coping and therefore also for animal welfare and productivity in the chicken industry. The mechanisms linking hatching time with post-hatch phenotype remain to be investigated.

    Place, publisher, year, edition, pages
    Public Library of Science, 2014
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:liu:diva-111296 (URN)10.1371/journal.pone.0103040 (DOI)000341354800055 ()25058654 (PubMedID)
    Note

    Funding Agencies|Swedish Research Council; Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning (Formas); European Research Council

    Available from: 2014-10-14 Created: 2014-10-14 Last updated: 2017-12-05
  • 35.
    Macdonald, Barry
    Linköping University, Department of Physics, Chemistry and Biology, Zoology .
    The effects of early stress on life-time strategies of behaviour and coping in chickens ( Gallus gallus )2011Independent thesis Advanced level (degree of Master (Two Years)), 60 credits / 90 HE creditsStudent thesis
    Abstract [en]

    Stress is often an important consideration for animal welfare. A number of factors can contribute to stress in domestic animals, most notably thoseused in food production. We investigated the effects and heritability of stress in domestic chickens (Gallus gallus). Using a spatial learning paradigm, we tested an early social isolation-stressed group and their offspring against unstressed controls, to determine if this cognitive function was negatively affected by stress. In the parental generation, we found that across sessions control birds improved in performance, indicating a learning trend. Stressed birds showed no difference across sessions, indicating a lack of learning. No effects of the parental treatment were found in the offspring of stress and control birds. Social isolation stress was found to affect spatial memory learning, however, we did not find evidence that the parental stress influenced the spatial abilities of the next generation despite changes in other behaviours.

  • 36.
    Mandenius, Carl-Fredrik
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biotechnology. Linköping University, The Institute of Technology.
    Björkman, Mats
    Linköping University, Department of Management and Engineering, Assembly technology. Linköping University, The Institute of Technology.
    Mechatronic design methodology for biotechnology products2009In: New Biotechnology, ISSN 1871-6784, E-ISSN 1876-4347, Vol. 25, no Suppl. 1, p. S190-S190Article in journal (Other academic)
    Abstract [en]

    Biotechnology products can be divided into (1) biologics, which comprise those metabolites, biopolymers, and cell structures that are produced through biological processes, and (2) biotechnical machines, which are apparatuses and devices that transform, change, or analyze ‘biological specimens’ for specific purposes, often by using the biological systems per se. The first category has been thoroughly treated in bioengineering theory and practice while the second has been very scarcely investigated.

    In this presentation is described how the general design science theory can be applied when designing a technical system where biological species or components have the key role in the engineering design solutions. We have named these systems bio-mechatronic systems, since they are combined design achievements between traditional electronic and mechanical sub-systems and the biological systems, and where biological molecules and/or active microbial or cellular components influence the design solutions in a complex way.

    The purpose is to demonstrate that biotechnology and bioengineering related design can utilize and benefit from other commonly used design tools in, for example, mechanical and electric engineering. These tools should result in shorter development times and a reduction of the need for prototype testing and verification.

    Four examples will be presented, all well-known biotechnology products in the pharmaceutical and clinical areas: (1) a protein purification system, (2) a bioreactor system, (3) a biosensor instrument, and (4) an embryonic stem cell manufacturing systems.

  • 37.
    Michno, Wojciech
    et al.
    Univ Gothenburg, Sweden.
    Nyström, Sofie
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Wehrli, Patrick
    Univ Gothenburg, Sweden.
    Lashley, Tammaryn
    UCL, England.
    Brinkmalm, Gunnar
    Univ Gothenburg, Sweden.
    Guerard, Laurent
    Univ Gothenburg, Sweden.
    Syvanen, Stina
    Uppsala Univ, Sweden.
    Sehlin, Dag
    Uppsala Univ, Sweden.
    Kaya, Ibrahim
    Univ Gothenburg, Sweden.
    Brinet, Dimitri
    Univ Gothenburg, Sweden.
    Nilsson, Peter
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Hammarström, Per
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry. Linköping University, Faculty of Science & Engineering.
    Blennow, Kaj
    Univ Gothenburg, Sweden; Sahlgrens Univ Hosp, Sweden.
    Zetterberg, Henrik
    Univ Gothenburg, Sweden; UCL, England; Sahlgrens Univ Hosp, Sweden; UCL, England.
    Hanrieder, Jorg
    Univ Gothenburg, Sweden; UCL, England.
    Pyroglutamation of amyloid-x-42 (Ax-42) followed by A1-40 deposition underlies plaque polymorphism in progressing Alzheimers disease pathology2019In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 294, no 17, p. 6719-6732Article in journal (Refereed)
    Abstract [en]

    Amyloid-β (Aβ) pathology in Alzheimer's disease (AD) is characterized by the formation of polymorphic deposits comprising diffuse and cored plaques. Because diffuse plaques are predominantly observed in cognitively unaffected, amyloid-positive (CU-AP) individuals, pathogenic conversion into cored plaques appears to be critical to AD pathogenesis. Herein, we identified the distinct Aβ species associated with amyloid polymorphism in brain tissue from individuals with sporadic AD (s-AD) and CU-AP. To this end, we interrogated Aβ polymorphism with amyloid conformation–sensitive dyes and a novel in situ MS paradigm for chemical characterization of hyperspectrally delineated plaque morphotypes. We found that maturation of diffuse into cored plaques correlated with increased Aβ1–40 deposition. Using spatial in situ delineation with imaging MS (IMS), we show that Aβ1–40 aggregates at the core structure of mature plaques, whereas Aβ1–42 localizes to diffuse amyloid aggregates. Moreover, we observed that diffuse plaques have increased pyroglutamated Aβx-42 levels in s-AD but not CU-AP, suggesting an AD pathology–related, hydrophobic functionalization of diffuse plaques facilitating Aβ1–40 deposition. Experiments in tgAPPSwe mice verified that, similar to what has been observed in human brain pathology, diffuse deposits display higher levels of Aβ1–42 and that Aβ plaque maturation over time is associated with increases in Aβ1–40. Finally, we found that Aβ1–40 deposition is characteristic for cerebral amyloid angiopathy deposition and maturation in both humans and mice. These results indicate that N-terminal Aβx-42 pyroglutamation and Aβ1–40 deposition are critical events in priming and maturation of pathogenic Aβ from diffuse into cored plaques, underlying neurotoxic plaque development in AD.

  • 38.
    Nantaba, Florence
    et al.
    Makerere University, Uganda.
    Wasswa, John
    Makerere University, Uganda.
    Kylin, Henrik
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Palm, Wolf-Ulrich
    Leuphana University of Lüneburg, Germany.
    Bouwman, Hindrik
    North-West University, South Africa.
    Kümmerer, Klaus
    Leuphana University of Lüneburg, Germany.
    Occurrence, distribution, and ecotoxicological risk assessment of selected pharmaceutical compounds in water from Lake Victoria, Uganda2020In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 239, article id 124642Article in journal (Refereed)
    Abstract [en]

    The occurrence of 24 pharmaceuticals (including; 15 antibiotics, three analgesic/anti-inflammatory drugs, three anti-epileptic/ antidepressant drugs, two beta blockers, and one lipid regulator) was investigated in 75 water samples collected from four bays in the Ugandan part of Lake Victoria. In addition, the potential environmental risk of the target pharmaceutical compounds to aquatic organisms in the aquatic ecosystem of Lake Victoria was assessed. Water samples were extracted using solid phase extraction and analyzed for pharmaceuticals using high- performance liquid chromatography coupled with triple quadrupole mass spectrometry (LC/MS/MS). Eighteen of the 24 pharmaceuticals occurred at quantifiable concentrations. Sulfamethoxazole (1-5600 ng L-1), trimethoprim (1-89 ng L-1), tetracycline (3-70 ng L-1), sulfacetamide (1-13 ng L-1), and ibuprofen (6-780 ng L-1) occurred at quantifiable concentrations in all water samples. Sulfamethazine (2-50 ng L-1), erythromycin (10-66 ng L-1), diclofenac (2-160 ng L-1), and carbamazepine (5-72 ng L-1) were only quantifiable in water samples from Murchison Bay. The highest concentrations of pharmaceuticals were found in Murchison Bay, the main recipient of sewage effluents, industrial and municipal waste from Kampala city via the Nakivubo channel. Ecotoxicological risk assessment showed that sulfamethoxazole, oxytetracycline, erythromycin, and diclofenac pose a high toxic risk to aquatic organisms in the lake, while ciprofloxacin, norfloxacin, and ibuprofen pose a medium risk. This study is the first of its kind to report the levels and ecotoxic risks of pharmaceutical compounds in Lake Victoria waters, of Uganda, and East Africa as a whole.

  • 39.
    Nauman, Laila
    Linköping University, Department of Physics, Chemistry and Biology.
    Operant conditioning in a self controlling test with a reinforcement delay in Pygmy Hippos (Hexaprotodon liberiensis)2010Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The curiosity whether or not animals have the characteristics of long term planning skills is fairly new. Some researchers agree that certain species have a form of episodic-like memory, in the terms of where, when and what. But the most difficult thing is to find out if these species have an aim for the future which involves what some call mental time travel. This study is a part of the discussion if the tests in long term planning and foresight can be explained by associative learning and the ability of self control in highly trained animals. Many self control and delay tasks have been conducted with laboratory animals such as rats, pigeons, monkeys and apes. Here we made a self control test with a reinforcement delay in pygmy hippos (Hexaprotodon liberiensis), an endangered species (listed as vulnerable at Cites, 2000), to extend the test among species. Also for trying to find out more about their cognitive skills, so we can better fulfil their needs in captivity. In this study, the female succeeded in 71,1 % (27 out of 38 trials) of the opportunities and the male in 84,2 % (32 out of 38 trials). To our knowledge this is the first study of learning and cognition in Pygmy hippos.

     

  • 40.
    Näsström, Åsa
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    The relationship between personality and basal metabolic rate in Red Junglefowl (Gallus gallus)2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    ‘Animal personality’ refers to individual behavioural differences that are consistent over time and context. Physiological constraints are suggested to underlie this constraint in behavioural plasticity. As energy is required for physiological processes that generate behaviour, energy metabolism could be a proximate explanation for personality. Currently, the most coherent framework linking behaviour, metabolism and life history-traits is still poorly tested empirically, and studies are showing contradicting results. Therefore, I here aim to explore this relationship further by investigating the relationship between basal metabolic rate (BMR) and personality in Red Junglefowl (Gallus gallus). Birds used had known responses in personality assays, and their metabolic rates were measured by determining oxygen consumption in standardized conditions throughout the night using an open respirometry system. BMR was negatively correlated with time spent foraging, and positively correlated with time spent being vigilant. Considering foraging an ‘activity’ (due to its energy-demand), my results support the allocation model, a model that assumes that an animal has a fixed amount of energy, thus that an energetic trade-off occur between competing energy requiring processes such as BMR and activity. Hence, an animal with low BMR has more energy to spend on activity. However, I do not consider vigilance as an energy-demanding activity; hence this relationship cannot be interpreted in this framework. Taken together, my results show a relationship between personality and BMR, although their relationship still needs further investigation to understand the causality and consequences of it.  

  • 41.
    Persson, Mia
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Trottier, Agaia J.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Bélteky, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Roth, Lina
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Jensen, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Intranasal oxytocin and a polymorphism in the oxytocin receptor gene are associated with human-directed social behavior in golden retriever dogs2017In: Hormones and Behavior, ISSN 0018-506X, E-ISSN 1095-6867, Vol. 95, p. 85-93Article in journal (Refereed)
    Abstract [en]

    The oxytocin system may play an important role in dog domestication from the wolf. Dogs have evolved unique human analogue social skills enabling them to communicate and cooperate efficiently with people. Genomic differences in the region surrounding the oxytocin receptor (OXTR) gene have previously been associated with variation in doge communicative skills. Here we have utilized the unsolvable problem paradigm to investigate the effects of oxytocin and OXTR polymorphisms on human-directed contact seeking behavior in 60 golden retriever dogs. Human-oriented behavior was quantified employing a previously defined unsolvable problem paradigm. Behaviors were tested twice in a repeated, counterbalanced design, where dogs received a nasal dose of either oxytocin or saline 45 min before each test occasion. Buccal DNA was analysed for genotype on three previously identified SNP-markers associated with OXTR. The same polymorphisms were also geno-typed in 21 wolf blood samples to explore potential genomic differences between the species. Results showed that oxytocin treatment decreased physical contact seeking with the experimenter and one of the three polymorphisms was associated with degree of physical contact seeking with the owner. Dogs with the AA-genotype at this locus increased owner physical contact seeking in response to oxytocin while the opposite effect was found in GG-genotype individuals. Hence, intranasal oxytocin treatment, an OXTR polymorphism and their interaction are associated with doge human-directed social skills, which can explain previously described breed differences in oxytocin response. Genotypic variation at the studied locus was also found in wolves indicating that it was present even at the start of dog domestication.

  • 42.
    Sander, Elin
    Linköping University, Department of Physics, Chemistry and Biology.
    Skip-a-day feeding does not cause difference in liver lipid content in broiler breeders2017Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There has long been evidence for increased lipids in the liver of chickens exposed to feed restriction, commonly used for production hens. Lipogenesis is an important part of the metabolism and storing of glucose, a source of energy. Few studies compare the difference of lipids in the liver in chickens between regular feed restriction and skip-a-day diets, despite differences in lipid content found in other organs and in overall carcass. In this study I experimentally investigate if a difference in lipid content can be found in broiler breeders exposed to two different feeding regimes, 65 % feed restriction and 5:2 skip-a-day, along with the difference between days and time points (a.m. and p.m.). I also experimentally investigate the effect on dry weights of the liver. I expected to see a difference in lipids of the liver, with an increase found in skip-a-day birds. However, a difference could only be observed in the dry weights of the livers in birds exposed to skip-a-day feeding. Although there was no significant change in lipids, there is a pattern for increase in lipids in skip-a-day birds. Therefore, the conclusion can be drawn that an increase in lipogenesis caused by skip-a-day diet exists but it was not big enough to cause a significant difference in lipid content. For the dry weights of the livers, we can suspect lipids and glycogen as the reason for the increased weight but to determine exactly how these two components affect the skip-a-day birds’ further inquiry is needed.

  • 43.
    Skog, Manfred
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Kvantifiering av näringsflöden i Recirkulerande Akvakultur (RAS) och nätkasseodling av lax (Salmo salar)2018Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Aquaculture has been a way to produce fish as a protein source for thousands of years and over the past decades aquaculture has been the fastest expanding animal-based food sector in the world. This study focused on quantifying the flows of nitrogen and phosphorus in Atlantic Salmon farming and compared traditional open net farming with a more recent technique, land based recirculating aquaculture system (RAS). The aim was to quantify the difference in emissions of nitrogen and phosphorus between the two types of farming and to quantify the amount of nutrients that could be reused from the respective fish farm. Data were obtained from reports, scientific publications and an application for environmental permit (EIA) for the case Smögenlax Aquaculture AB. The same feed input and salmon output were assumed in the two systems and a substance flow analysis was used to quantify the flows of nutrients. The amount of produced salmon and fish feed/year were taken from Smögenlax Aquacultures EIA. The results showed that a RAS-based Salmon farm emits only 6 % of the nitrogen and 5 % of the phosphorus emitted to the recipient waters in comparison to an open net farm. RAS-based salmon farming also enables the reuse of 19 % more nitrogen and 47 % more phosphorus than an open net farm by using sludge and fish offal from the farm to create biogas and biofertilizers. RAS is still evolving to provide possibilities for large scale salmon farms on land to be both cost and environmental efficient and may in the future be the most common way to farm Atlantic Salmon.

  • 44.
    Sköldsson, Julia
    Linköping University, Department of Physics, Chemistry and Biology.
    Is There a Correlation Between Eye Preference and Visual Acuity, Eye Dominance, and Handedness in Humans?2019Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Most humans do not only have a preferred hand to use in different situations, they also exhibit a clear preference when it comes to eye usage. Few studies have assessed whether different tests of eye preference give congruent or incongruent results, and furthermore, there are conflicting findings on whether eye preference correlates with eye dominance, visual acuity, and handedness. The present study assessed whether these variables correlate, alongside factors such as age and sex. A total of 79 subjects, 45 males and 34 females, were tested. A microscope, telescope, photo camera, and caleidoscope were used to assess eye preference, the Dolman test was used to assess eye dominance, the Edinburgh Handedness Inventory was filled in to assess handedness, and visual acuity was measured using a Snellen chart. Care was taken to include subjects of various ages and both sexes. Descriptive statistics show that most subjects were right-handed, had a right-eye preference and were consistent across the four eye preference tasks, and had a dominant right eye. Significant correlations were found between visual acuity and handedness, as well as eye preference and eye dominance.

  • 45.
    Steinhoff, Franciska S.
    et al.
    Department of Marine Botany, University of Bremen, Bremen, Germany / Section Functional Ecology, Department Seaweed Biology, Alfred-Wegener Institute for Polar and Marine Research, Bremerhaven, Germany.
    Graeve, Martin
    Section Ecological Chemistry, Alfred-Wegener Institute for Polar and Marine Research, Bremerhaven, Germany.
    Bartoszek, Krzysztof
    Mathematical Sciences, Chalmers University of Technology and the University of Gothenburg, Sweden.
    Bischof, Kai
    Department of Marine Botany, University of Bremen, Bremen, Germany.
    Wiencke, Christian
    Section Functional Ecology, Department Seaweed Biology, Alfred-Wegener Institute for Polar and Marine Research, Bremerhaven, Germany.
    Phlorotannin Production and Lipid Oxidation as a Potential Protective Function Against High Photosynthetically Active and UV Radiation in Gametophytes of Alaria esculenta (Alariales, Phaeophyceae)2012In: Photochemistry and Photobiology, ISSN 0031-8655, E-ISSN 1751-1097, Vol. 88, no 1, p. 46-57Article in journal (Refereed)
    Abstract [en]

    Radiation damage can inter alia result in lipid peroxidation of macroalgal cell membranes. To prevent photo-oxidation within the cells, photoprotective substances such as phlorotannins are synthesized. In the present study, changes in total fatty acids (FA), FA composition and intra/extracellular phlorotannin contents were determined by gas chromatography and the Folin-Ciocalteu method to investigate the photoprotective potential of phlorotannins to prevent lipid peroxidation. Alaria esculenta juveniles (Phaeophyceae) were exposed over 20 days to high/low photosynthetically active radiation (PAR) in combination with UV radiation (UVR) in the treatments: PAB (low/high PAR + UV-B + UV-A), PA (low/high PAR + UV-A) or low/high PAR only. While extracellular phlorotannins increased after 10 days, intracellular phlorotannins increased with exposure time and PA and decreased under PAB. Interactive effects of time:radiation wavebands, time:PAR dose as well as radiation wavebands:PAR dose were observed. Low FA contents were detected in the PA and PAB treatments; interactive effects were observed between time:high PAR and PAB:high PAR. Total FA contents were correlated to extra/intracellular phlorotannin contents. Our results suggest that phlorotannins might play a role in intra/extracellular protection by absorption and oxidation processes. Changes in FA content/composition upon UVR and high PAR might be considered as an adaptive mechanism of the A. esculenta juveniles subjected to variations in solar irradiance.

  • 46.
    Svensson, Joakim
    Linköping University, Department of Physics, Chemistry and Biology.
    Reintroducing captive bred species: a community ecological perspective2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Throughout history species has gone extinct due to anthropogenic activities. During the last century efforts have been done to reintroduce species back into the wild. Zoos that originally were created as amusement parks for people have today a new purpose; to keep and breed species in captivity for later reintroductions in the wild. However a relaxed environment such as a zoo leads to a general fitness decline of up to 40% per generation in captivity. The probability of a successful reintroduction of a species that has been bred in a zoo will be lower the longer time it has been kept in captivity. The reintroduction of a captive bred species can also cause secondary extinctions and other negative effects on the food-web. Both changes in the community caused by the loss of a species and changes in the species itself caused by captivity can be expected to affect the outcome of a reintroduction attempt. Using a modeling approach I here investigate how the reintroduction of a captive bred species (at three different trophic levels; basal, intermediate and top predator species) affects a food-web and what risks there are in reintroducing it. A Lokta-Volterra model with type II functional response is used. I investigate three scenarios: the reintroduction of a species with 0% change in its attributes, 40% change in its attributes and 75% change in its attributes. It was found that the most important factor for reintroduction success when reintroducing a species is whether it is a producer species (basal species) or a consumer species (intermediate and top predator species). The producer species were most sensitive to the changes in their attributes, whilst consumer species were more sensitive to change in the food-web (Euclidian distance). The producer species were found to cause most secondary extinctions in all scenarios, hence indicating that it is a bottom-up controlled food-web. The present study suggests that the success of a reintroduction attempt is affected both by the degree of changes in the food web caused by the initial loss of the species and the degree of change in the species itself caused by captivity.

  • 47.
    Säterberg, Torbjörn
    Linköping University, Department of Physics, Chemistry and Biology.
    Minimum Ecologically Viable Populations: Risk assessment from a multispecies perspective2009Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    The extinction risk of threatened species has traditionally been assessed by the use of tools of Population Viability Analysis (PVA). Species interactions, however, have seldom been accounted for in PVA:s. The omission of species interactions in risk assessments may further lead to serious mistakes when setting target sizes of populations. Even a slight abundance decrease of a target species may result in changes of the community structure; in the worst case leading to a highly impoverished community. Of critical importance to conservation is therefore the question of how many individuals of a certain population that is needed in order to avoid this kind of consequences. In the current study, a stochastic multispecies model is used to estimate minimum ecological viable populations (MEVP); earlier defined as “the minimum size of a population that can survive before itself or some other species in the community becomes extinct”. The MEVP:s are compared to population sizes given by a single species model where interactions with other species are treated as a constant source incorporated in the species specific growth rate. MEVP:s are found to be larger than the population sizes given by the single species model. The results are trophic level dependent and multispecies approaches are suggested to be of major importance when setting target levels for species at the basal level. Species at higher trophic levels, however, are altogether more prone to extinction than species at the basal level, irrespective of food web size and food web complexity.

  • 48.
    Södergren, Anna
    Linköping University, Department of Physics, Chemistry and Biology.
    Vasodilatory effects of exogenous nitric oxide on the brood patch of the Zebra finch (Taeniopygia guttata)2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In birds like the Zebra finch (Taeniopygia guttata) the female, but not the male develop a brood patch upon incubation of eggs. The brood patch functions to increase heat exchange between the bird and the eggs. Development of the brood patch includes de-feathering, increased vascularization and edema formation. The increased vascularization is due to the development of arteriovenous anastomoses, AVA. The AVA are thermoregulatory vessels involved in cold induced vasodilation, CIVD, demonstrated to occur in the brood patch. Nitric oxide, NO, which is a well known vasodilator is a candidate substance for involvement in CIVD. In this study a NO-generating gel was applied to the brood patch of male and female zebra finches. Vasodilation was found to be markedly larger in females than in males. The larger vasodilation in the female brood patch is probably because NO vasodilate AVA selectively more than any other vessels. The study also investigated whether vasodilation would cause an increase in brood patch temperature. No definite changes in brood patch temperature could be observed and no conclusions could be drawn in the matter.

  • 49.
    Wallstedt, Lennart
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. 630307-3354.
    Hassel (Corylus avellana) som indikator på markanvändningshistorik2015Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Hazel (Corylus avellana L.) is a common feature of meadows and pastures where it can grow in large populations and become very old. Is it possible to use the size of hazel stools for age determination and is it possible to use the size distribution of a population to provide information about how the land has been used? Hazel populations on ground where the lake-water level had been lowered, has been studied to validate an already developed growth model of hazel clones. Different hazel populations, on wooded meadows affected by mowing or grazing or overgrown meadows, were studied to evaluate the method utilizing hazel as land use indicator. The growth model was used to compare the size distributions of hazel populations with historical periods, which has been important for changes in agriculture or demography. The results show that the current growth model needs to be refined, but the method itself with a growth model based on the circumference of hazel bushes seems feasible. Additional studies about the influence of, for example, soils of different fertility are needed. The results also show that the size distribution in a population depends on how much meadows have been affected by mowing or grazing and that areas with similar land use have similar size distribution. Finally, some examples are reported about how a growth model can be used to compare historical periods of changes in agriculture, for example reduced livestock, with variations of the size distribution in a hazel population.

  • 50.
    Weddfelt, Erika
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Recyling potential of phosphorus in food: a substance flow analysis of municipalities2012Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    In this study the opportunities to recycle the phosphorus contained in food handling were identified in four municipalities in the county of Östergötland. The aim was to map the flow and find out whether there were differences between municipalities with food processing industries generating large amounts of waste or phosphorus rich wastewater, or if there were differences between municipalities of different size. It was also investigated to what extent the agricultural demand of phosphorus could be covered by recycling of phosphorus from the food handling system. The result showed that between 27% and 73% of the phosphorus was found in the sludge from wastewater treatment, and that between 13% and 49% of the phosphorus was found in the centrally collected organic waste. This corresponded to 11% of the phosphorus demand on arable land in municipalities with food processing industries generating large amounts of waste or phosphorus rich wastewater, and 8% of the phosphorus demand on arable land in municipalities without such industries.

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