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Beteende och fysiologiska reaktioner hos människovana grävlingar i fälla / Behavioural and physiological reactions in trapped semi-tame badgersStrömgren, Anna Karin January 2004 (has links)
Det här är en studie med syftet att ta reda på hur grävlingar reagerar på att vistas i fälla och om det kan påvisas att djuren upplever stress. Fällvistelserna har varit korta och långa, under dagtid samt nattetid. Grävlingarnas beteenden, hjärtfrekvens och kroppstemperatur har studerats. I materialet finns även en metod för insamling av underlag till stresshormon analys. Datainsamling har gjorts dels under vistelsen i fälla, men även under de närmast följande dygnen efteråt samt under en avslutande period av naturligt beteende. Grävlingarna i studien var fyra honor och uppfödda i hägn och var vad jag kallar människovana. För att studera beteende har grävlingarna filmats och materialet analyserats. För telemetri (hjärtfrekvens och kroppstemperatur) har utrustning med sändare inopererade i buken på grävlingarna använts. Min slutsats är att grävlingarna blev påverkade av vistelsen i fällan. Det yttrade sig i en ökad hjärtfrekvens och hög fysisk aktivitet. Ökad hjärtfrekvens uppmättes även hos grävlingar som till synes var lugna vilket visar att de var påverkade fast det inte syns på beteendet. Grävlingarna var något aktivare under nattbehandlingarna än under dagbehandlingarna. Då resultaten i den här studien tyder på att djuren lider, bör reglerna för kontroll och användande av fälla undersökas närmare.
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Finns det verkligen mikroorganismer i kaveldun? En ämnesfördjupning- en läroprocess / Are there really microorganisms present in cattail? Subject deepening : teaching processesMalmström, Maria, Sundblad, Camilla January 2004 (has links)
Metan är en växthuseffektpåverkande gas. Eftersom dess koncentration ökar i atmosfären ingår den i ett stort framtida, globalt miljöproblem. I uppdraget som lärare står att elever ska göras medvetna kring de processer som påverkar deras miljö. Vårt syfte med uppsatsen är att fördjupa våra ämneskunskaper i och kring de processer som påverkar vår miljö. Detta för att göra ndervisningen mer intressant och för att kunna leda eleverna mot en kunskapsutveckling i ett ämne som är högst aktuellt. Uppsatsens studie består i att undersöka om det finns metanbildande eller metankonsumerande mikroorganismer i kaveldun, Typha latifolia, (L.) och var i kaveldunet de i så fall finns. Vi vill också lyfta vår egen läroprocess under arbetets gång och se om det finns något där som är användbart i vårt kommande yrkesliv, som lärare, inspiratör och som föredöme. I vår undersökning upptäckte vi att det i kaveldunet fanns både metanogener och metanotrofer. I sedimentet fanns både metanogener och metanotrofer. Vi fick klara indikationer på att det fanns metanogener i kaveldunets nedre delar och vi såg att de växte på vätgas och på acetat. Vi fann också att metanotrofer uppehöll sig i kaveldunets rothår och rotnerv och i den övre delen av kaveldunet. Sist, men inte minst, fick vi upp ögonen för vikten av att lärande måste komma inifrån individen för att förståelse helt och fullt ska uppstå. För att skapa intresse är det viktigt att arbeta med relevanta och meningsfulla frågeställningar. Dessa frågeställningar behöver vi inte konstruera, de finns redan färdiga i vår omvärld och det är frågor som ungdomar i dag har. / The greenhouse gas, methane, palys an important role in the future climate change on the globe. The curriculum given to teachers constitutes that pupils should be aware of the different processes affecting their environment. The purpose of this report is to deepen our knowledge on such processes tohelp us to fullfil this requierment. Hence, this should aid us in making our teaching more interesting and also to enable us to lead the pupils in a knowledge development on a very urgent environmental topic. The study examines, if there are microorganisms that produce or consume methane in cattail, Typha Latifolia (L.), and if so, where in the cattail tissues. During our work with the report we also wanted to follow our own teaching process and to highlight phenomena useful in our future professional lives as teachers, inspirers and as good examples. We observed that methanogens and methanotrophs were present in cattail tissues as was allso the case in the sediment samples. We got clear indications on that there were methanogenes in the lower parts of the cattail and we saw that they grew on hydrogen gas and on acetate. The methanotrophs resided in the root hair and root nerves as well as in the upper part of the cattail plant. We realised that it is important for learning to arise from within the individual for the establishment of a complete understanding of an evironmental issue. To create an interest by any pupil category, it’s important to work with relevant and meaningful questions. We don’t need to construct these questions, they already exist in our surroundings, many of which are the questions of the young people today.
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Mag-tarmkanalens anatomi och fysiologi / Anatomy and physiology of the gastrointestinal canalGullberg, Petra January 1999 (has links)
Detta examensarbete handlar om mag-tarmkanalen och är uppdelat i två avsnitt. Den första delen handlar om mag-tarmkanalens uppbyggnad, rent anatomiskt men också hur den ser ut histologiskt. Histologin är bara ytligt behandlad då den endast är med som förklaring till vissa händelser inom fysiologin. Den andra delen, fysiologidelen handlar om de olika delarna i mag-tarmkanalen, deras funktioner och vad som reglerar dessa. I fysiologiavsnittet behandlas också nedbrytning och absorption av de olika näringsämnena.
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Stress Coping Strategies in Rainbow Trout (Oncorhynchus mykiss)Schjolden, Joachim January 2005 (has links)
Animals show a great variety in physiological and behavioural responses to stressors. These responses are often bimodally distributed within populations and show consistency on an individual level over time and across situations, which in terrestrial vertebrates have been identified as proactive and reactive stress coping strategies. Proactive animals show lower cortisol responses, higher sympathetic activation and brain serotonergic activity compared to reactive animals. Behaviourally, proactive animals are more aggressive, more active in avoiding stressors, they form routines and show fewer cases of conditioned immobility compared to reactive animals. Our aim has been to reveal if such stress coping strategies exist in fish. Our results show that rainbow trout with high (HR) or low (LR) cortisol responses to stressors differs in sympathetic activation and brain serotonin turnover in the same manner as proactive and reactive mammals. HR fish showed less locomotor activity when reared in large groups (30 individuals) compared to LR fish. When reared in isolation there were no differences between HR and LR fish when exposed to stressors within a familiar environment. The adaption of a proactive coping style among reactive coping individuals when they are challenged within a familiar environment has previously been shown to be distinction between proactive and reactive coping mammals. However, when they were transferred to unfamiliar environments a behavioural difference between the two lines was observed indicating different stress coping strategies akin to those described in mammals. Finally, we observed a consistency over time in the cortisol response of an unselected line of rainbow trout. Fish from this line also demonstrated a correlation between behavioural responses to different stressors. However, there was no apparent connection between these behavioural responses and the cortisol response. Overall, the results of this thesis have strengthened the hypothesis that different stress coping strategies exist in teleost fish.
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Neurotoxic Effects of Dichlorophenyl Methylsulphones Related to Olfactory Mucosal LesionsCarlsson, Carina January 2003 (has links)
This thesis deals with the highly potent olfactory mucosa toxicant 2,6-dichlorophenyl methylsulphone (2,6-diClPh-MeSO2) and its non-toxic 2,5-chlorinated isomer (2,5-diClPh-MeSO2). In mice, both substances bind firmly in the olfactory mucosa and the olfactory bulb, which are important components of the sensory system. The 2,6-isomer induces olfactory mucosal necrosis with permanent loss of olfactory neuroepithelium and olfactory nerves. A major objective was to clarify the cause of this isomer-specific toxicity, and to identify which physicochemical characteristics determine the olfactory toxicity. The neurobehavioural toxicity of these substances was also examined. The results revealed a rapid CYP-catalysed covalent binding of 2,6-diClPh-MeSO2 in the rat olfactory mucosa, whereas the 2,5-dichlorinated isomer was not covalently bound. Acute and chronic olfactory mucosal pathology were investigated and compared in rats and mice. Twenty-four hours after dosing to rats, 2,6-diClPh-MeSO2 induced Bowman’s glands necrosis and sloughing of the olfactory epithelium similar to that previously reported in mice. At 3 weeks, however, there were dramatic differences in histological lesions. In mice, large parts of olfactory epithelium were replaced by respiratory-like epithelium. Large, bilateral, fibrous, cartilage and bone containing polyps occluding the lumen were confirmed. In rats, only minor patches of olfactory epithelium were replaced by a metaplastic atypical respiratory-like epithelium. 2,5-diClPh-MeSO2 was non-toxic in rats as well as in mice. In mice, 2,6-diClPh-MeSO2 induced a dose-dependent and long-lasting ( ≥12 weeks) hyperactivity as well as long-lasting maze learning deficits. At 2 weeks hyperactivity and maze learning deficits were observed also in rats. Unexpectedly, 2,5-diClPh-MeSO2 induced hyperactivity that lasted for two weeks. No effect on maze learning was observed with this isomer. No major differences between male and female rats or mice were found. In conclusion, the results show that a CYP-catalysed formation and covalent binding of a reactive 2,6-diClPh-MeSO2-metabolite in the Bowman’s glands precede the high olfactory mucosal toxicity in rodents. As determined by QSAR-modelling, a 2,6-dichlorinated benzene derivative with a large, polar, and strong electron withdrawing substituent in the primary position has the potential of being an olfactory mucosal toxicant. The observed 2,6-diClPh-MeSO2-induced increase in motor activity, and maze learning deficits, were not correlated to the olfactory mucosal lesions. I propose that 2,6-diClPh-MeSO2 causes a direct effect in the brain leading to neurobehaviuoral deficits.
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Biologiundervisning utomhus : En studie av utomhusundervisningen inom biologiämnet i grundskolans senare år. / Outdoor education in biology : A study of outdoor education in biology in the later years of compulsory school.Johansson, Matilda, Hansen, Åsa January 2008 (has links)
<p>Syftet med detta arbete är att studera utomhusundervisning inom biologiämnet i grundskolans senare år. Arbetet syftar även till att fastställa Ekobussens roll i utomhusundervisningen. Frågeställningarna lyder som följande:</p><p>•Vilken inställning har lärare till utomhusundervisning inom biologi?</p><p>•Vad finns det för fördelar och nackdelar med utomhusundervisning?</p><p>•Vad får elever ut av utomhusundervisning?</p><p>•Hur använder sig lärare av Ekobussen och vilken inställning har de till den?</p><p>För att få svar på dessa frågor genomfördes en enkätundersökning med lärare och elever samt djupintervjuer av tre lärare.</p><p>Resultatet i undersökningen visar att både lärare och elever anser att utomhusundervisning inom biologiämnet inte bedrivs i tillräcklig utsträckning. Orsaker till detta är bland annat osäkerhet hos lärare, brist på bra exkursionsplatser i närområdet samt att det är schematekniskt svårt att få tid att komma ut.</p><p>Undersökningen visar att de stora fördelarna med utomhusundervisning inom biologi är att eleverna anser sig koppla teoretisk och praktisk kunskap samman samt att många sinnen stimuleras vilket underlättar inlärningen.</p> / <p>The purpose of this work is to study outdoor education in biology, in the later years of compulsory school, and to investigate the role of “Ekobussen” in outdoor education. The questions at issue runs:</p><p>•What do teachers think about outdoor education in biology?</p><p>•What benefits and disadvantages are there with outdoor education?</p><p>•What do the pupils gain by outdoor education?</p><p>•What are the attitudes of “Ekobussen” by teachers and how do they use it in their work?</p><p>To answer these questions we handed out a questionnaire to both teachers and pupils, and we also interviewed three teachers.</p><p>The result of the investigation shows that both teachers and pupils believe that they are not having enough outdoor education in biology. The causes of this are among other things; unsure teachers, no good outdoor areas to examine in the immediate surroundings of the school and lack of time.</p><p>The investigation shows that the greatest advantages of outdoor education in biology are that the pupils feel that they can connect theoretical- and practical knowledge and that many senses are stimulated which facilitates learning.</p>
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Protein production, characterization and structure determination in structural genomicsWoestenenk, Esmeralda A. January 2004 (has links)
<p>This thesis covers the process from expression of a heterologous gene in Escherichia coli to structure determination of a protein by nuclear magnetic resonance (NMR) spectroscopy. </p><p>The first part concerns structural genomics-related parallel screening studies on the effect of fusion tags (in particular the His tag) on protein solubility and the use of fusion tags in fast, parallel purification protocols intended for initial biophysical characterization of human proteins produced in E. coli. It was found that for most proteins the His tag has a negative influence on protein solubility. This influence appears to be more pronounced for our C-terminal His tag than for the N-terminal His tags used in this study. Moreover, high ratios of soluble per total protein do not always guarantee a high yield of soluble protein after purification, as different vector - target protein combinations result in large differences in host cell growth rates. Protein purification protocols for different fusion tags were developed that make it possible to express, purify and study structural properties of low concentration samples of 15N-labeled proteins in one or two days. </p><p>The second part of this thesis describes the assignment and solution structure determination of ribosomal protein L18 of Thermus thermophilus. The protein is a mixed α/β structure with two α-helices on one side of a four-stranded β-sheet. Comparison to RNA-bound L18 showed that the protein to a large extent adopts identical structures in free and bound states, with exception of the loop regions and the flexible N-terminus.</p><p><b>Keywords:</b> protein production, protein solubility, fusion tags, nuclear magnetic resonance, structure determination, ribosomal protein</p>
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Approaches to Species Delineation in Anamorphic (mitosporic) Fungi : A Study on Two Extreme CasesVinnere, Olga January 2004 (has links)
Since the beginning of mycology, studies of species concept in fungi have been mainly based on morphology, partially due to the history of mycology as part of botany. Current advances in biochemical and molecular research have provided mycologists with powerful tools that can be used for delineation of fungal taxa. Recently, an integrated approach to fungal taxonomy involving both morphological and molecular traits has found a wide application for identification of species, especially in anamorphic (mitosporic) fungi. In this thesis, I have tried to use this approach for identification of species units in two rather unrelated groups of organisms. One of the case studies concerned Colletotrichum acutatum – a worldwide economically important plant pathogenic anamorphic fungus, which is exhibiting a high level of variation in both morphological and molecular features. This fungus has been intensively studied during the past decades, and several attempts have been made to find reliable markers to separate it from other closely related species of Colletotrichum. The second case studied in this thesis was Mycelia Sterilia – an artificial group of fungi, which are deficient in production of spores of any kind, therefore lacking the main morphological feature used for assigning them to any certain fungal taxon below class level. Due to this peculiarity, Mycelia Sterilia have usually been neglected, and currently there is no working species concept applicable to these fungi. In this work, I have tried to clarify the relationships among C. acutatum and several other anamorphic (C. gloeosporioides and C. fructigenum) and teleomorphic (Glomerella acutata, G. cingulata and G. miyabeana) taxa that are closely related to each other. For this purpose, examination of morphological traits was employed in combination with comparison of DNA sequencing data from three loci and subsequent phylogenetic analysis. As a result, re-description of C. acutatum and separation of (at least) two new species was proposed. For studies of Mycelia Sterilia, a large collection of sterile strains was screened in search for biologically interesting organisms. One novel pathogen has been found, and two plant growth promoting strains with antifungal properties were selected. Attempt for tentative identification of those fungi was made based on their morphological, physiological and molecular features. Sequencing of several genes and spacers of the ribosomal DNA array revealed that the plant pathogenic strain is closely related to the teleomorphic basidiomycete genus Campanella, and plant growth-promoting isolates were identified as belonging to the anamorphic ascomycete genus Phoma. However, assigning the sterile strains to any existing species was not possible. The main conclusion of the thesis is that species in anamorphic fungi should be defined based on a combination of morphological and molecular methods, both equally important, involving as many aspects of fungal biology as is possible at our current state of knowledge.
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Food and Parasites – Life-history Decisions in CopepodsSivars Becker, Lena January 2004 (has links)
In the freshwater copepod, Macrocyclops albidus, food availability, rearing conditions and tapeworm infection clearly affected various life-history traits and their trade-offs. I found that low food availability clearly constrained resource allocations to several life-history (often phenotypically plastic) traits, whereas high food availability either allowed for adjustments in resource allocation patterns or allowed resources to be allocated to several traits without apparent trade-offs. Both male and female copepods allocated resources according to food availability; developing more slowly and achieving smaller adult body size when food was scarce. When food availability was low females were constrained and produced fewer eggs (in total and per clutch), and started reproduction later than females with more food available. Males under low food availability allocated relatively more to spermatophore size (current reproduction) with decreasing body size. In contrast, when food availability was high males allocated resources to body size as well as spermatophore size. Overall, at maturity, copepods of both sexes were more similar in size than in age, suggesting that large body size was more important for fitness than fast development. In nature the prevalence of copepods infected with cestode tapeworms was found to be low (0-3%). Female copepods, experimentally infected with the cestode Schistocephalus solidus, showed lower overall fecundity, especially when food availability was low. However, infected females produced a larger proportion of their life-time egg production early in life than non-infected females. This might be an adaptation to reduce future fitness costs of infection. Females grown under bad rearing conditions, but with high food availability, produced their first clutch earlier than females grown under good rearing conditions, indicating an adjustment in timing of reproduction. These findings contribute to our fundamental evolutionary understanding of how environmental conditions interact with life-history traits.
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The Control of the EpigenomeLezcano, Magda January 2006 (has links)
The genetic information required for the existence of a living cell of any kind is encoded in the sequence information scripted in the double helix DNA. A modern trend in biology struggles to come to grip with the amazing fact that there are so many different cell types in our body and that they are directed from the same genomic blueprint. It is clear, that the key to this feature is provided by epigenetic information that dictates how, where and when genes should be expressed. Epigenetic states “dress up” the genome by packaging it in chromatin conformations that differentially regulate accessibility for key nuclear factors and in coordination with differential localizations within the nucleus will dictate the ultimate task, expression. In the imprinted Igf2/H19 domain, this feature is determined by the interaction between the chromatin insulator protein CTCF and the unmethylated H19 imprinting control region. Here I show that CTCF interacts with many sites genome-wide and that these sites are generally protected from DNA methylation, suggesting that CTCF function has been recruited to manifest novel imprinted states during mammalian development. This thesis also describes the discovery of an epigenetically regulated network of intra and interchromosomal complexes, identified by the invented 4C method. Importantly, the disruption of CTCF binding sites at the H19 imprinting control region not only disconnects this network, but also leads to significant changes in expression patterns in the interacting partners. Interestingly, CTCF plays an important role in the regulation of the replication timing not only of the Igf2 gene, but also of all other sequences binding this factor potentially by a cell cycle-specific relocation of CTCF-DNA complexes to subnuclear compartments. Finally, I show that epigenetic marks signifying active or inactive states can be gained and lost, respectively, upon exposure to stress. As many genes belonging to the apoptotic pathway are upregulated we propose that stress-induced epigenetic lesions represent a surveillance system marking the affected cells for death to the benefit of the individual. This important observation opens our minds to the view of new intrinsic mechanisms that the cell has in order to maintain proper gene expression, and in the case of misleads there are several check points that direct the cell to towards important survival decisions.
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