Spelling suggestions: "subject:"biologiska vetenskaplig"" "subject:"biologiska vetenskapliga""
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Exploration behaviour, habitat choise and territorial defence behaviour in captive reared and released naive adult tawny owls.Eriksson, Emil January 2021 (has links)
Territoriality is a behaviour that has evolved to secure resources for survival and reproduction. We know very little about how individuals become territorial, and such information may be important in release programs for threatened species. In this paper I study the establishment of a territory and the habitat choice of captive-raised tawny owls, a year-round territorial bird of prey. The aim is to find out how fast these naïve tawny owls claim their own territory and what type of environment they most likely do establish territory within. In total 19 tawny owls were released, four of these owls were equipped with remote downloading GPS loggers attached as backpacks to study their habitat choice and explorative behaviour. My results suggest that 82 % of the owls successfully establish territory on average 22 days after the release. I was not able to download data from the GPS loggers with the downloading station, which is most likely due to the GPS signal having difficulties traveling through the closed forest which is interfering with the signal. This indicates that this type of automatic downloading GPS is not suitable for this type of forest-dwelling species. A large proportion of the owls became territorial very fast after they have been released, showing strong territoriality instinct in these naive individuals. This may suggest that released naïve tawny owls can successfully claim a territory and thereby contribute to the pool of reproductive individuals.
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The Relationship Between Duration of Smartphone Usage and Inhibitory Control : A Stroop and Stop-Signal Task InvestigationStrauss, Dahni January 2021 (has links)
The smartphone has quickly become the most used device to access the internet. Academic and public concern has been raised if overuse of smartphone technology can have detrimental effects on brain and behavior. Preliminary results suggest that excessive smartphone usage may be linked to impaired inhibitory control. The present study investigates whether such a relationship is present in a sample of healthy individuals with varying degrees of usage. To investigate the proposed relationship, the Stroop color and word task and the stop-signal task was utilized to measure inhibitory control, while screen time was utilized to measure duration of smartphone usage. A Pearson‘s correlation analysis and an independent t-test/Mann Whitney-U test analyzed the results, which did not yield statistical significance.
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Växtartrikedomens svar på restaurering av hävdade gräsmarker : En litteraturstudie / The Response of Plant Species Richness on Restoration of Semi-natural Grasslands : A ReviewBergström, Elin January 2021 (has links)
En av de naturtyper med flest antal växtarter i världen är hävdade gräsmarker som är präglade av traditionell skötsel. Denna naturtyp har minskat kraftigt i area och för att förhindra framtida artutdöenden är restaureringsåtgärder viktiga. Syftet med denna rapport var att med hjälp av vetenskapliga publikationer undersöka vilken effekt restaurering av före detta hävdade gräsmarker i norra och centrala Europa har på växtartrikedomen. Mer specifikt undersöktes effekten av olika restaureringsmetoder på totala antalet arter, arttätheten och artsammansättningen. Utöver detta undersöktes vilka faktorer som påverkar möjligheten till restaurering. Resultatet tyder på att restaurering med bete eller slåtter är mest framgångsrik av de olika undersökta metoderna. Restaurering med bete eller slåtter visade sig kunna ha en positiv effekt på totala antalet arter, arttätheten och artsammansättningen. Enbart rensning av träd och buskar var inte en långsiktigt hållbar metod för restaurering eller bevarandet av artrikedomen eller arter associerade med hävdade gräsmarker. Det finns många faktorer som påverkar möjligheten till restaurering och alla är inte entydiga. Något som kan vara intressant att vidare utforska är vilken betydelse de olika artrikedomsmåtten och artsammansättningen har för att kunna optimera restaureringsprojekt. Förutom att restaurering av hävdade gräsmarker både kan bidra till att utöka Natura 2000-nätverket och uppfylla de globala målen, ger det oss mängder med ekosystemtjänster och bevarande av kulturlandskap.
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Kartläggning av fluviala påverkansfaktorer hos biflödesmynningsområden inom Klarälvens avrinningsområde : Utgör biflödesmynningsområdena hot-spots för fisk? / Identifying environmental factors in tributary mouths within the catchment area of Klarälven : Do tributary mouths constitute hot-spots for fish?Andersson, Mikael January 2020 (has links)
Sammanfattning Biflödesområden och sammanflödeszoner spelar en viktig roll, inte minst genom deras förmåga att förändra miljöförhållandena och framkalla ett biologiskt svar i huvudfåran de rinner ut i. Biflödesområden utgör även platser med högt inneboende ekologiskt värde, där särskilda biofysiska processer och ekologiska tjänster ofta är koncentrerade. Syftet med denna studie var att undersöka huruvida biflödesmynningsområden inom Klarälvens avrinningsområde utgjorde hotspots för fisk samt kartlägga eventuella fluviala påverkansfaktorer. Parametrar som studerades var artförekomst och medeltäthet samt omvärldsfaktorerna medeldjup, lokalbredd, bottensubstrat, vattennivå, vattenhastighet och förekomsten av vandringshinder i vattendraget. Flest arter återfanns i Klarälvens huvudfåra, varpå biflödesmynningarna hade näst flest arter och uppströms biflödena lägst antal arter. Medeltäthet av arterna bergsimpa (Cottus poecilopus), elritsa (Phoxinus phoxinus) och lake (Lota lota) var störst i biflödesmynningarna, medan medeltätheten av lax (Salmo salar) och öring (Salmo trutta) var som störst uppströms biflödena. Resultatet visade också att öring, i större utsträckning än lax, förekom högre uppströms i biflödena, ett förhållande som även stödjs av tidigare studier. Gällande omvärldsfaktorerna var vattenhastigheten signifikant högre i biflödemynningarna och uppströms biflödena jämfört med i huvudfåran, samtidigt som det högsta diversitetsvärdet för bottensubstratkompositionen återfanns i huvudfåran. Utifrån dessa resultat var det svårt att dra en slutsats kring om biflödesmynningarna faktiskt utgjorde hotspots för fisk eller inte, då det skiftade beroende på vilka parametrar som studerades. En bedömning gjordes att biflödesmynningsområden inom Klarälvens avrinningsområde inte utgjorde hotspots för fisk. Nyckelord: Biflödesmynning, biflöde, huvudfåra, Klarälven, flottning, vattenkraft / Abstract Tributary areas and confluence zones play an important role, not least through their ability to change environmental conditions and elicit a biological response in the main stream they flow into. Tributary areas also provide sites of high inherent ecological value, where specific biophysical processes and ecological services are often concentrated. The purpose of this study was to investigate whether tributary mouths within the catchment area of Klarälven constituted hotspots for fish and to identify possible environmental factors associated with hotspots. Parameters studied were species composition and mean density, as well as the physical factors such as average depth, local width, bottom substrate, water level, water velocity and the occurrence of migratory obstacles in the watercourse. Most species were found in the mainstream, whereas tributary mouths had the second highest species richness and upstream tributaries had the lowest number of species. The mean density of the alpine bullhead (Cottus poecilopus), eurasian minnow (Phoxinus phoxinus) and burbot (Lota lota) was greatest in the tributary mouths, while the mean density of salmon (Salmo salar) and trout (Salmo trutta) was greatest upstream of the tributaries. The results also showed that trout, to a greater extent than salmon, occurred higher upstream in the tributaries, a relationship that is also supported by previous studies. Regarding the physical factors, water velocity was significantly higher in the tributary mouths and upstream tributaries than in the mainstream, while the highest diversity for bottom substrate composition was found in the mainstream. Based on these results, it was difficult to conclude whether tributary mouths actually constituted hotspots for fish or not, as it varied depending on the parameters studied. Overall tributary mouths within the catchment area of Klarälven did not constitute hotspots for fish. Keywords: Estuary, tributary, mainstream, river, rafting, hydropower
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Hur substrat och avstånd från vatten påverkar strandvegetation vid Ölmans avrinningsområde / Effects of substrate and distance from the stream on riparian vegetation in the Ölman watershedJohansson, Julia January 2020 (has links)
Avrinningsområden är landområden där det ofta finns förutsättningar för stor biologisk mångfald. År 2017 var ett område som undersöktes Ölmans avrinningsområde, där man dokumenterade och räknade antal individer av de olika växtarter som fanns på olika avstånd från vattnet, samt de olika vegetationstypernas procentuella täckning av marken. Det här är en undersökning som, i hopp om att ge en bättre förståelse för vegetationszonering vid vattendrag, försöker upptäcka huruvida det finns en skillnad i artmångfald och artfördelning på två olika substrat och på tre olika avstånd från vattnet vid Ölmans avrinningsområde i Värmland, Sverige. Alla data som användes i undersökningen hade redan samlats in i juli 2017. Analysen skedde under hösten 2018. Resultaten påvisade inget samband mellan substrat och artmångfald och artfördelning. Avståndet från vattnet hade inte heller någon inverkan på artmångfald och artfördelning. Ölmans avrinningsområde är påfallande litet, vilket med sannolikhet påverkar förekomst av naturlig zonering – eller en brist därav. Det finns också flera andra biotiska och abiotiska faktorer som kan påverka växtlivet, såsom pH-värden i vattnet och jorden, mänsklig påverkan, påverkan från djur, och så vidare. Att enbart känna till grovleken på det underliggande substratet ger inte tillräckligt med information för att tillåta dragande av några definitiva slutsatser gällande vegetationsstrukturen. / Watersheds are areas of land that often have the prerequisites for great biological diversity. In 2017 one area being examined was the Ölman watershed, where different plant species were accounted for, both by species and amount of individuals, on different distances from the water, as well as the percentage of ground coverage of different types' of vegetation. This is a study that, in an attempt to better understand vegetation zones along rivers and streams, tries to discover whether there is a statistically significant difference between the species diversity and species distribution on two different substrates and three different distances from the water of the Ölman watershed in Värmland, Sweden. All data used for the study were collected in July 2017 and analysed in autumn 2018. The results showed no relationship between substrate and species diversity or species distribution. The distance from the water did not have any effect on the species diversity or species distribution either. The Ölman watershed is quite small, which is likely to affect the presence of natural zoning – and the lack thereof. There are also several other biotic and abiotic factors that can influence plant life, such as pH of the water and soil, human and animal interference, etc. Only knowing the coarseness of the substrate does not provide enough information to be able to draw any definite conclusions on the vegetation structure.
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Mechanisms of action of β-blockers for the treatment of heart failureBurman, Jonas January 2020 (has links)
Heart failure is a syndrome in which the heart is unable to supply the entire body with oxygen. It is manifested in shortness of breath and exercise intolerance. One class of drugs that have proven effective in managing the progression of heart failure is β-blockers. These drugs bind to β-adrenergic receptors with high affinity, thus preventing the binding of endogenous catecholamines such as epinephrine and norepinephrine to the receptors by outcompeting them. The most common explanation of how β-blockers help manage the progression of heart failure is that by slowing the heart rate, it reduces the strain put on the heart. There may however be other ways that β-blockers help decrease morbidity and mortality of heart failure. Alternative reasons to how β-blockers aid the treatment of heart failure have been proposed based on the literature. It was found that the compensatory mechanisms intended to alleviate failure may be the main reasons that actually worsen it. Prolonged stimulation by epinephrine and norepinephrine damage the myocardium through oxidative damage, signaling for apoptosis and cardiac remodeling, as well as causing an increase in blood volume through the RAS-system. By blocking these maladaptive responses, β-blockers such as Carvedilol, Metoprolol and Nebivolol, together with other drugs such as ACE-inhibitors, and lifestyle changes help manage the progression of heart failure as well as increase the quality of life for the patients suffering from it
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The Tumor Promoting Actions of Exosomal miRNAsJohansson, Emil January 2020 (has links)
Exosomes are nanosized vesicles that contain proteins and nucleic acids. They are released and taken up by many different cell types as a way of cell-to-cell communication. It has previously been recognized that exosomes released by cancer cells promote tumor progression. Moreover, recent studies have increasingly found evidence that microRNA contained within cancer derived exosomes plays an important role in tumor progression. In this manuscript, the current knowledge on exosomes, the sorting of microRNA into exosomes as cargo, the gene regulatory mechanisms of microRNA, and recent findings on the tumor promoting actions of exosomal microRNAs on gastric cancer, hepatocellular carcinoma and breast cancer, is reviewed. The information gathered emphasizes the importance of exosomal microRNAs that increase tumor growth in the development of cancer treatment and research.
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Sex differences in COVID-19 infections / Könsberoende skillnader i COVID-19 infektionerSpahi, Majlinda January 2020 (has links)
The Coronavirus disease 2019 (COVID-19) outbreak have shown that there may be sex-dependent differences in morbidity and mortality among individuals contracted with the disease. The aim of the study was to analyse the extent that sex differences appear in COVID-19 infections and to explore whether any differences are due to intrinsic factors in the sexes that cause sex-bias in the disease susceptibility and mortality. The study presents an age and sex-disaggregated analysis of reported cases of total infections, intensive care cases, and deaths across 13 countries due to the disease. The results demonstrated that there is a general trend for the disease prevalence, and it shows a female bias among the proportion of individuals infected with COVID-19. However, males appear to require more intensive care treatment and higher rates of death when compared to females. The results also show that more women than men are reportedly infected by the corona virus up to a certain age. After the age of 60, the proportion of men affected is higher than women, and it is also at this age that the death rate among men increases significantly. In conclusion, the results of this work indicate that males could possibly be at a significantly higher risk of severe disease and death than females, and that the patterns of sex bias in intensive care cases to some extent follows the expected pattern if sex hormones played a role in influencing the immune system response to COVID-19. / Utbrottet av Coronavirus sjukdomen 2019 (COVID-19) har visat att det kan finnas könsberoende skillnader i sjuklighet och dödlighet bland individer som drabbats av sjukdomen. Syftet med studien var att analysera i vilken utsträckning könsskillnader förekommer i COVID-19-infektioner och att undersöka om skillnaderna beror på inre faktorer hos könen som möjligtvis orsakar könsfördomar i sjukdomens mottaglighet och dödlighet. Denna studie presenterar en ålder-och könsfördelad analys av totala antalet rapporterade fall, intensivvårdsfall och dödsfall i 13 länder till följd av COVID-19. Resultaten visade att det finns en generell trend för sjukdomens utbredning, och den visar en högre andel kvinnor än män som har smittats med COVID-19. Men det är män som är mer i behov av intensivvård och har högre dödsnivåer i jämförelse med kvinnor. Resultaten visar även att fler kvinnor än män smittas av coronaviruset upp till en viss ålder. Efter 60-årsåldern är andelen drabbade män högre än kvinnor, det är även vid den här åldern som dödsnivån bland män ökar markant. Sammanfattningsvis indikerar resultaten av denna studie att män eventuellt skulle kunna ha en betydligt högre risk för en allvarligare sjukdom och död än kvinnor.
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Har det skett en förändring i abborrens (Perca fluviatilis) tillväxt i sjön Tåkern mellan år 1978 jämfört med år 2019? / Has There Been Any Change in Growth in Perch (Perca fluviatilis) in Lake Tåkern Between the Year 1978 Compared to Year 2019?Felicia, Skorsdal January 2020 (has links)
The growth in perch (Perca fluviatilis) is generally slow but varies depending on living conditions. For instance, growth is more rapid in warmer water temperature and when there is reduced intra- and interspecific competition for food. The cormorant (Phalacrocorax carbo) was established in Lake Tåkern in 1994 and could possibly have an effect on the growth of perch due to predation of small perch and competition for food with larger perch. The aim of this study was to examine whether the growth of perch had changed from year 1978, when a previous study on perch was preformed, to a recent fish survey in 2019 in lake Tåkern. The aim of the study was to assess if any changes in growth could be explained by predation and competition from cormorants. The aim of the study was also to examine whether there was a difference in growth between females and males. The age was determined by using the opercular bone and an age analysis was done to compare the growth between year 1978 and 2019. The results showed that the growth of 1-3-year-old perch was higher in year 1978 than in 2019. This was contrary to the expected outcome, that the predation from cormorants should had decreased competition for young perch in 2019. Previous studies on perch have shown a difference between males and females with an age over 2 years old. However, by the results there is no support that differences between males and females have affected the difference in growth at ages 1-3 years old between 1978 and 2019. As there was no difference between the sexes, any difference in growth between 1978 and 2019 could not be explained by an altered sex ratio. Since there were only a few older individuals 2019 comparison of growth for individuals over 4 years old were not possible to do. The conclusion is that there was no support that cormorants reduced the competition for smaller perch. Cormorants could possibly have contributed to low number of older individuals in 2019.
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Optimisation of PCR Protocol for Microsatellites in Vaccinium myrtillus : A first step in evaluating genetic diversity for future conservationFahlgren, Sandra January 2022 (has links)
A growing world population means an increase in crop demand. At the same time climate change threatens food security as crops may become maladapted to a new environment. We need to adapt crops to increase crop yield and become resistant to a changed environment to meet this. Crop wild relatives (CWR), which have a genetic relatedness with our crops, will be of importance as a genetic resource for crop adaption and needs to be protected. Vaccinium myrtillus is one of the prioritized species on the Nordic countries CWR priority list. Here I report PCR protocols that can be used for amplifying microsatellites, or SSRs, within V. myrtillus for use in analyses of genetic diversity within and between populations. PCRs with varying annealing temperatures (Ta) were performed. An optimal Ta for the primer pair was found for four SSR loci, and for four SSR loci, an approved Ta was found. These eight primer pairs can be used to amplify SSRs for analyses of the genetic diversity between V. myrtillus populations. This is needed to evaluate which populations to focus on in conservation programmes to ensure a broad genetic diversity usable in crop adaptation to meet increasing crop demand and climate change.
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