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Kristen Aaltonen Andrew A. Bryant Jeffrey A. Hostetler Madan K. Oli 《Biological conservation》2009,142(10):2181-2190
Recovery of the endangered Vancouver Island marmot (Marmota vancouverensis) is contingent upon releases of captive-born marmots into natural habitats. Success of such re-introduction programs largely depends on the ability of released animals to survive in the wild. However, whether and to what extent survival and cause-specific mortality rates of captive-born marmots differ from those of their wild-born counterparts remains unknown. We used radio-telemetry (1992–2007) and mark-resighting (1987–2007) data to estimate seasonal and annual survival rates of the Vancouver Island marmot, to compare survival and cause-specific mortality rates of captive-born marmots that have been released into the natural habitat with those of wild-born marmots, and to test for the effect of age-at-release on survival of the released marmots. Analysis of radio-telemetry data suggested no difference in survival of males versus females. However, annual survival of captive-born marmots released into the wild was low (S = 0.605; 95% CI = 0.507–0.696) compared to wild-born marmots (S = 0.854; 95% CI = 0.760–0.915). Marmots released as 2-year-old or older survived more successfully than those released as yearlings. Additional forensic evidence reinforced the idea that predation was the most important cause of mortality. Causes of death differed significantly between captive-born and wild-born marmots. Predation by golden eagles (Aquila chrysaetus) was the most important cause of mortality for captive-born marmots, whereas predation by wolves (Canis lupus) and cougars (Felis concolor) was more important for wild-born marmots. Age-specific apparent annual survival rate, estimated using the combined mark-resighting and radio-telemetry data, was lowest for pups (S = 0.500; 95% CI = 0.375–0.616) and highest for yearlings and adults (S = 0.656; 95% CI = 0.604–0.705); and apparent survival of 2-year-old was similar to that of yearlings and adults (S = 0.649; 95% CI = 0.527–0.754). Our results, based on the analysis of radio-telemetry data, suggest that delaying release of captive-born marmots until 2 years of age may enhance their probability of survival in the wild, and will likely improve the success of the release program. 相似文献
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Tarkhov M. O. Matyshak G. V. Ryzhova I. M. Goncharova O. Yu. Bobrik A. A. Petrov D. G. Petrzhik N. M. 《Eurasian Soil Science》2019,52(8):945-953
Eurasian Soil Science - Palsa peatland soils are known as significant terrestrial storage of the Earth’s soil carbon. The response of these soils to changing climate may result in a strong... 相似文献
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An improved means of isolating zein is needed to develop new uses for corn zein. We have measured the yield of zein and evaluated the ability of acetic acid to remove zein from corn gluten meal, distillers dried grains, and ground corn using acetic acid as solvent. Acetic acid removed zein more quickly, at lower temperatures, and in higher yields when compared with alcoholic solvents. After 60 min at 25°C, ≈50% of the zein in corn gluten meal was removed. A step change in yield from 43 to 50% occurs as the extraction temperature is increased from 40 to 55°C after mixing for 30 min at 25% solids. The protein composition of the zein removed from corn gluten meal using acetic acid is very similar to that of commercial zein by SDS‐PAGE. The zein obtained from corn gluten meal using acetic acid had higher amounts of fatty acids and esters according to IR analysis, leading to slightly lower protein content. Films made from zein extracted from corn gluten meal using acetic acid had lower tensile strength (≈60% lower) than films produced from commercial zein. Fibers with very small diameter (0.4–1.6 μm) can be produced by electrospinning using the AcOH solution obtained after corn gluten meal extraction. 相似文献
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Kristen E Whalen Victoria R Starczak David R Nelson Jared V Goldstone Mark E Hahn 《BMC ecology》2010,10(1):24
Background
Intense consumer pressure strongly affects the structural organization and function of marine ecosystems, while also having a profound effect on the phenotype of both predator and prey. Allelochemicals produced by prey often render their tissues unpalatable or toxic to a majority of potential consumers, yet some marine consumers have evolved resistance to host chemical defenses. A key challenge facing marine ecologists seeking to explain the vast differences in consumer tolerance of dietary allelochemicals is understanding the biochemical and molecular mechanisms underlying diet choice. The ability of marine consumers to tolerate toxin-laden prey may involve the cooperative action of biotransformation enzymes, including the inducible cytochrome P450s (CYPs), which have received little attention in marine invertebrates despite the importance of allelochemicals in their evolution. 相似文献220.
ASVCP quality assurance guidelines: control of general analytical factors in veterinary laboratories
Flatland B Freeman KP Friedrichs KR Vap LM Getzy KM Evans EW Harr KE 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(3):264-277
Owing to lack of governmental regulation of veterinary laboratory performance, veterinarians ideally should demonstrate a commitment to self-monitoring and regulation of laboratory performance from within the profession. In response to member concerns about quality management in veterinary laboratories, the American Society for Veterinary Clinical Pathology (ASVCP) formed a Quality Assurance and Laboratory Standards (QAS) committee in 1996. This committee recently published updated and peer-reviewed Quality Assurance Guidelines on the ASVCP website. The Quality Assurance Guidelines are intended for use by veterinary diagnostic laboratories and veterinary research laboratories that are not covered by the US Food and Drug Administration Good Laboratory Practice standards (Code of Federal Regulations Title 21, Chapter 58). The guidelines have been divided into 3 reports on 1) general analytic factors for veterinary laboratory performance and comparisons, 2) hematology and hemostasis, and 3) clinical chemistry, endocrine assessment, and urinalysis. This report documents recommendations for control of general analytical factors within veterinary clinical laboratories and is based on section 2.1 (Analytical Factors Important In Veterinary Clinical Pathology, General) of the newly revised ASVCP QAS Guidelines. These guidelines are not intended to be all-inclusive; rather, they provide minimum guidelines for quality assurance and quality control for veterinary laboratory testing. It is hoped that these guidelines will provide a basis for laboratories to assess their current practices, determine areas for improvement, and guide continuing professional development and education efforts. 相似文献