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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Influence of landscape scale and habitat distribution on individual bat species and bat species richness

Brüsin, Martin January 2013 (has links)
Habitat fragmentation is one of the most important factors affecting species extinction and biodiversity loss, Species habitat response expects to differ with habitat feature at different spatial scales and this study was to identify how bat diversity and individual bat species respond to different habitat amounts. The local bat species richness was observed in 156 different locations in Östergötland and the proportion of different habitats were calculated for circular areas with diameters ranging from 400 m. to 12 km. from each location. Although we found that the individual bat species responded differently to the amount of each habitat at different spatial scales, the bat species richness showed a decreasing response with increasing spatial scale. The strongest response of bat species richness to habitat characteristics was at a scale of 939 m.
72

The Effect of Cold Acclimation on Changes in Muscle Activity

Hans Christian, Tingelstad 24 October 2013 (has links)
Human beings have been exposed to different cold conditions throughout time, and have through cold acclimation developed mechanisms to survive in these conditions. Cold acclimation can be elicited through exposure to natural cold climates, or artificially induced in a laboratory to study the body’s response to repeated cold exposures. Several studies looking at the effects of cold acclimation in humans have been conducted during the last 50 years, and have reported that cold acclimation can lead to a change in skin and core temperature, heat production and shivering. An accurate quantification of shivering thermogenesis (ST) during cold acclimation has not been done before, and most previous measurements of shivering during cold acclimation have been inaccurate and inadequate. In this study a Liquid Condition Suits (LCS) was used to elicit cold acclimation (10°C, 2hr daily, for 4 weeks) while an accurate measurement of the effect of cold acclimation on changes in muscle activity was conducted. In CHAPTER 2, results showed that four weeks of cold acclimation at 10°C did not change skin and core temperature, heat production or ST. The effects on shivering pattern and fuel selection were also analysed, but no effects of cold acclimation could be observed. These measurements were a part of a larger study, in which the effects of cold acclimation on changes in BAT were the main outcome measures. These data showed that an increase in BAT volume (45%) and activity (120%) were the only observed effects of cold acclimation. In CHAPTER 3, we set out to assess if changes in shivering from pre to post cold acclimation are associated with changes in BAT volume, and if the amount of BAT a participant possesses prior to cold acclimation can be used to predict changes in shivering intensity during cold acclimation. The interindividual variability in changes in thermal responses, heat production, shivering and BAT volume occurring between subjects during four weeks of cold acclimation was also addressed in this section.
73

Habitat associations among bats on Redstone Arsenal, Alabama

Gardner, Sara Elizabeth, Best, Troy L., January 2008 (has links)
Thesis--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references.
74

Foraging habitat selection of Ohio bats an examination between eastern second growth forest, eastern old growth forest, and pasture land /

Carter, Richard T. January 2008 (has links)
Thesis (M.S.)--Ohio University, March, 2008. / Title from PDF t.p. Includes bibliographical references.
75

Sound duration selectivity in bat midbrain inferior colliculus

Wu, Chung-Hsin, January 2006 (has links)
Thesis (Ph. D.) University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 9, 2007) Vita. Includes bibliographical references.
76

Spatial and Temporal Patterns in Insectivorous Bat Activity in River-Riparian Landscapes

January 2010 (has links)
abstract: River and riparian areas are important foraging habitat for insectivorous bats. Numerous studies have shown that aquatic insects provide an important trophic resource to terrestrial consumers, including bats, and are key in regulating population size and species interactions in terrestrial food webs. Yet these studies have generally ignored how structural characteristics of the riverine landscape influence trophic resource availability or how terrestrial consumers respond to ensuing spatial and temporal patterns of trophic resources. Moreover, few studies have examined linkages between a stream's hydrologic regime and the timing and magnitude of aquatic insect availability. The main objective of my dissertation is to understand the causes of bat distributions in space and time. Specifically, I examine how trophic resource availability, structural components of riverine landscapes (channel confinement and riparian vegetation structure), and hydrologic regimes (flow permanence and timing of floods) mediate spatial and temporal patterns in bat activity. First, I show that river channel confinement determines bat activity along a river's longitudinal axis (directly above the river), while trophic resources appear to have stronger effects across a river's lateral (with distance from the river) axis. Second, I show that flow intermittency affects bat foraging activity indirectly via its effects on trophic resource availability. Seasonal river drying appears to have complex effects on bat foraging activity, initially causing imperfect tracking by consumers of localized concentrations of resources but later resulting in disappearance of both insects and bats after complete river drying. Third, I show that resource tracking by bats varies among streams with contrasting patterns of trophic resource availability and this variation appears to be in response to differences in the timing of aquatic insect emergence, duration and magnitude of emergence, and adult body size of emergent aquatic insects. Finally, I show that aquatic insects directly influence bat activity along a desert stream and that riparian vegetation composition affects bat activity, but only indirectly, via effects on aquatic insect availability. Overall, my results show river channel confinement, riparian vegetation structure, flow permanence, and the timing of floods influence spatial and temporal patterns in bat distributions; but these effects are indirect by influencing the ability of bats to track trophic resources in space and time. / Dissertation/Thesis / Ph.D. Biology 2010
77

Emise tuhých znečišťujících látek v chovu drůbeže

JANOUŠEK, Tomáš January 2016 (has links)
Agricultural activities produce a number of dangerous wastes affecting the environment. One is powder produced in livestock production, in particular in stables factory farms. Particulate emissions from livestock buildings are particularly important for the closest neighborhood stables. It is the subject of conflicts between farmers and their neighbors. The source of dust in livestock buildings are mainly food (fine particles modified cereals and dried plants) renegade animal skin particles, urine crystals and particles of feces. The aim of this work is to determine the concentration of dust in the factory farming of chickens for meat. Secondly, the aim is to compare BAT (Best Available Technique - Best Available Technology) technology used in stables with the reference document BREF (Integrated Pollution Prevention and Control - Integrated Pollution Prevention and Control). Measurements were carried out on a Farma U lesa in Sudoměřice u Bechyně on a poultry farm in Horní Miletín.
78

Měření emisí zátěžových plynů z vybraných BAT technik ve zvoleném provozu s chovem prasat, zhodnocení jejich ekonomických dopadů a porovnání s vypočtenými hodnotami dle dokumentu BREF

HADÁČEK, Aleš January 2017 (has links)
This diploma thesis aims to measure the harmful gas emissions and evaluate methods and technologies used in an observed fattening pigs company. Subsequently observed methods and technologies are compared with best available techniques BATs and economically evaluated. The thesis contains three hypotheses. 1. Do measured production emissions of ammonia from the selected plant comply with the limits and recommendation of EU directives? 2. Is the applied BAT suitable from the economical point of view even for Czech agriculturists? 3. Do measured values comply with the decrease of ammonia levels according to the calculated decrease in the BREF document? The measured values and subsequent evaluation show that the production emissions of ammonia comply with the EU directives. However, the measured ammonia emissions are significantly lower than the theoretical values calculated according to the legislation that takes into account the used technology. BAT-reducing technologies used in the plant are suitable for Czech agriculturists.
79

IS DISRUPTION TO PASSIVE GAS-EXCHANGE A MECHANISM OF DEHYDRATION FOR WNS-INFECTED HIBERNATING BATS?

Carey, Charleve 01 August 2014 (has links)
Emergent epizootics are responsible for dramatic declines in wildlife populations over the past few years. An emerging fungal-borne epizootic, called white-nose syndrome (WNS), is responsible for a catastrophic decline of hibernating bats in North America The fungus, Pseudogymnoascus destructans (Pd), is the causative agent of WNS, but to date, we have limited understanding of how an infection with Pd can lead to mortality in hibernating bats. Evidence suggests dehydration is an important part of the pathogenesis of WNS. Cryan et al. (2010) proposed four possible mechanisms by which infection could lead to dehydration. In this study, I tested one of these hypotheses - Pd infection could cause disruption to passive gas-exchange pathways across the wing membranes, thereby causing a compensatory increase in water-intensive pulmonary respiration. I hypothesized total evaporative water loss would be greater when passive gas-exchange was inhibited, especially at low ambient temperatures. I found that bats did not lose more water when passive gas-exchange was retarded (at least within the resolution of my equipment). This study provides evidence against the proposed proximal mechanism that disruption to passive gas-exchange causes dehydration and ultimately death to WNS-infected bats.
80

Stanovení indikátorů BATve velkochovech hospodářských zvířat

Dědina, Martin January 2004 (has links)
No description available.

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