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568 Uppsatser om Teachability hypothesis - Sida 37 av 38

Retention of stumps on wet ground at stump-harvest and its effects on saproxylic insects

Low stumps represent on their own up to 80% of the dead wood remaining on clear cuts and therefore supply suitable habitat for saproxylic insects i.e. insects depending on dead wood for their survival. Recent stump harvesting activities threaten this substrate of ecological importance and increase the anthropogenic negative impacts on these species. Because of technical and environmental reasons (nutrient leakage, erosion) guidelines for stump harvesting recommend to retain stumps standing in wet parts of clear cuts. However, stumps in wet positions might not be a satisfactory substrate for saproxylic insects and therefore might not be as much used as stumps in dry positions.

Seroprevalence of Rift Valley fever in sheep and goats in Zambezia, Mozambique and preparations for a metagenomic study of arboviruses in ticks

The virus-mediated disease Rift Valley fever (RVF) was discovered during an outbreak in Kenya in the 1930s. Since then it has spread to most parts of Sub-Saharan Africa, and in the last decades several outbreaks have caused economic and health issues in Africa, Yemen and Saudi-Arabia. The disease mainly affects domestic livestock, causing abortions, but is also a zoonosis. To be able to control the spread of the disease it is important with surveillance for better knowledge about the distribution and virus circulation even in inter-epidemic/epizootic periods. The human population is growing, and people and their livestock constantly move closer to areas with wild animals which act as reservoirs for different viruses. Also, humans and their animals often get within reach for arthropod vectors, hosting or carrying viruses.

Cross-sectional study of bovine anaplamosis in South-western Uganda : the impact of wildlife-livestock interface

The tick-borne disease bovine anaplasmosis is primarily caused by Anaplasma marginale. A variety of wild animals act as reservoirs for A. marginale, but the understanding of their role in the epidemiology of A. marginale is yet poor. This cross-sectional study was conducted to establish if proximity of wildlife affect the prevalence of bovine anaplasmosis in cattle.

Framtagning av ett nytt recept för clear-coat batter av pommes frites : En teknisk och sensorisk utvärdering

The requirements of good quality and appetizing fast food increases continuously as a consequence of a community where food is always available. The crispiness of French fries is an issue that must be considered in this context, since it tends to decrease and give the fries a soft surface not appreciated by the consumer. To prolong the crispiness, the fries can be coated by a batter, a mix of starches. The batters used often consists of modified starches, e.g. cross-linked, acetylated and dextrinizated to increase and prolong crispiness, flour to stabilize the batter and sodium bicarbonate to make the batter ?rise?.The cross-linked starch keeps the granules in a swelled state and prevents them from breaking when exposed to heat or processing: therefore, it delays the gelatinization and decreases the stickiness of the batter.

Att restaurera forna tiders beståndsstruktur : ett exempel från Jämtgaveln

In Sweden today so-called "prescribed nature conservation burning" is performed due to the change in silvicultural law, certification and an increased knowledge regarding the field of fire in the forest landscape. The aim is to re-create structures and qualities made by the fire regimes of the past, though on a much smaller geographical scale. The structures and qualities to be re-created are for example broad leaf stands, trees with large diameter, heterogeneous stands regarding variables such as age and diameter. If we increase our knowledge of the constitution of forests characterized by fire, then we will be able to set goals for what achievements to reach both on landscape scale and stand scale. The aim of this paper is to try to describe how a stand from the past was composed regarding mainly the spatial arrangement and compare it with the stand of today in the same place. This to be done by using relict material, that is stumps and dead standing trees.

Sjukdomsfrekvens och utslagningsorsaker hos kor med 12 respektive 15 månaders kalvningsintervall

The incidence of many of the most common diseases in dairy cattle has been proven to be highest during the time closest to calving. It is possible that the current breeding strategy with 12 month calving intervals increases the risk for disease in dairy cattle, which is problematic concerning both animal welfare and for economic reasons. The economic incentives behind a calving interval of 12 to 13 months have mainly been based on milk- and feed- costs and no costs due to diseases or fertility disturbances have been included.The aim of this study was to see if a lengthening of the calving interval would result in lower disease frequency. The hypothesis is that cows with a planned calving interval of 15 months have a lower disease incidence than cows with a calving interval of 12 months due to less number of calvings. Therefore the difference in disease frequency should be larger when compared over a long period of time, such as over lifetime, since cows with a longer calving interval experience fewer calvings.The study was performed between August 17th, 1994, and January 24th, 2007.

Levande vikt vid olika åldrar och sambandet med bröstomfång och mankhöjd hos SRB och SLB :

Live-weight at different ages for Swedish Holsteins (SLB) and for the Swedish Red and White Breed (SRB), and the correlation to heart girth and height at withers. The aim of this investigation was to study the live-weight changes and mature weight for the Swedish Red and White Breed (SRB) and for Swedish Holsteins (SLB), and to estimate the correlations between body weight and body measurements such as heart girth and height at withers, respectively. The material used was from one of the experimental dairy herds (Jälla) of the Swedish University of Agricultural Science. It included recordings on 293 dairy cows with information from 7142 weight occasions and recordings on 275 dairy cows with information of 557 heart girth measurements and 560 measurements of height at withers. The registrations were done during 1993-2002. There was a large variation in live weight between cows in different ages and lactation stages.

Debuten av gluten ? Har tidpunkt för glutenintroduktion någon betydelse för risken att utveckla celiaki hos högriskbarn?

AbstractTitle: The debut of gluten ? Does timing of gluten introduction affect the risk ofceliac disease in high-risk children?Author: Sandra Hagwall Frohm and Maria IngmarSupervisor: Frode SlindeExaminer: Mette AxelsenProgramme: Programme in dietetics, 180/240 ECTSType of paper: Bachelor?s thesis in clinical nutrition, 15 hpDate: May 26, 2015Background: Celiac disease is a chronic disease in which the intestinal mucosa is damaged bygluten exposure, and the only treatment is a lifelong gluten-free diet. The disease affects about1 % of the population worldwide, but the majority are undiagnosed. Ingestion of gluten and thegenotype HLA-DQ2/8 are required for disease development, although additional genetic andenvironmental factors are believed to be of importance. One hypothesis is that timing of glutenintroduction in infants affects the disease risk.

Markberedningens, planteringspunktens och behållardjupets inflytande på granminiplantors etablering i fält :

A new type of forest tree seedling, called mini seedling, has been developed by the University of Dalarna in Garpenberg, Sweden. Compared to traditional containerized seedlings that are grown for 1 ? 2 years, mini seedlings are grown for only 10 weeks. The mini seedlings are small, easily planted, cost effective, and reduce the amount of chemicals used in the nursery. Research has shown that mini seedlings tend to have higher overall survival rates than traditional container seedlings.

Farmakogenomikens betydelse för individvariationen avseende biverkningar och resultat vid Paclitaxel behandling av hund

Purpose The purpose of this study is to evaluate the treatment results and adverse drug effects for 14 dogs receiving a new paclitaxel preparat named Paccal vet. The evaluated dogs are chosen to enter a pharmacogenomical study. Therefore, this paper intends to give an introduction to pharmacogenomics. Finally this study also aims at finding the homologue genesequenses in dogs to seven genes that are important for metabolism of paclitaxel in humans. Materials and metods The dogs went through 2-4 cycles of paclitaxel treatment, they received a new water-soluble formula named Paccal vet, at dosages of 100-150mg/m2. Treatment results and adverse effects are listed for each dog in table 1.

Genetisk studie av inavel och fertilitet hos hund :

Inbreeding, the mating of related individuals, has been the one dominating breeding strategy for dog breeders during the last 200 years. However, its negative effects on fer-tility and other fitness traits, a phenomenon called inbreeding depression, have been ignored in the quest of perfect unity in conformation or performance. The purpose of this study was to test the hypotheses that litter size is reduced as a consequence of in-breeding, affected by both the inbreeding coefficient of the dam and the litter and that a rapid increase in the inbreeding coefficient affects litter size more than a slower rate. Data were collected from the Swedish Kennel Club registry of origin. Breeds included in the study were the Bernese Mountain Dog, the Cocker Spaniel, the Golden Retriever, the Rottweiler and the West Highland White Terrier.

The role of mast cells and mast cell mediators in the development of atopic dermatitis in a mouse model

Atopic dermatitis (AD) is a complex, often lifelong allergic disease affecting around 10 % of both dogs and humans. The hallmark symptom is severe pruritus, causing a lowered quality of life. Mast cells (MCs) are known to play an important part of the immunopathogenesis, promoting a faulty T helper cell type 2 (Th-2) response which follows by a production of specific immunoglobulin E (IgE) antibodies towards environmental allergens (Ag). To further investigate the role of MCs and its mediators in the progression of AD, a low-calcemic vitamin D3 analog (MC903) was used to induce AD-like symptoms locally on the ears of two different knock-out (KO) mouse strains. The first strain was Wsh-/- mice deficient in MCs.

Optimalt mottagningsstall för kalvar : en fältstudie

A cattle producer that buys calves that are younger than six months to the herd should have a starter stable to prevent infection spreading in the herd. According to the Swedish animal welfare regulation there has to be a starter stable if more than 50 calves that are younger than four months are bought in yearly to the herd. The aim of the study was to improve the knowledge about bovine buildings and management of starter stables to obtain optimal weight gain and health of the calves. The hypothesis 1) The younger the calves are when purchased, the higher the calf mortality and 2) Purchasing calves from a high number of herds involves a higher risk of calf health problems and calf mortality were tested in the study. The objective of the study was to give advices by way of presenting ideal solutions of how a starter stable should be constructed and managed. A field study was done during June to September 2008 to collect knowledge and experience from existing starter stables.

Underprissättning, hur kommer det sig? : En kvantitativ studie av de extremaste introduktionerna på börsen.

SammanfattningBörsintroduktion eller IPO (Initial Public Offering) är något som sker när ett företag väljer att notera sig på en marknad. När detta sker visar forskning bl.a. att aktien stiger kraftigt under första dagen på börsen, vilket leder till slutsatsen att aktierna varit prissatta för lågt innan börsintroduktionen och att aktierna i genomsnitt är underprissatta innan de noterats på börsen. Vissa svenska studier indikerar att denna underprissättning i genomsnitt är så stor som 34,10 % när ett svenskt företag introduceras på börsen. Varför det är på det här sättet har forskningen inte kunnat svara på, flertalet förklaringsmodeller har framlagts, utan att någon vunnit konsensus.

Grödans kontra odlingssystemets effekt på frilevande nematoder

Nematodes are perhaps the most common animals in the world. Nematode populations can reach densities up to several millions per square meter in the soil. There are many factors which affect nematode communities in arable soil with respect to diversity and population size. Factors like tillage, crop, fertilization, nutrient status and moisture in the soil all have an impact on soil biology and in this way also have effects on the nematode community. This study is based on three different parts, soil samples taken in March 2012 and March 2013, soil samples taken monthly during the growth season of 2013 in bare fallow plots and a pot experiment.

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