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31.
We detected Hepatitis E virus in serum samples of wild rabbits that were hunted in 1989 around the city of Greifswald, Germany. The recovery of one partial sequence and subsequent phylogenetic analysis indicates a close relationship to rabbit HEV sequences from France and suggests a long-established circulation of rabbit HEV in Europe.  相似文献   
32.
Mortality of animals on roads is a critical threat to many wildlife populations and is poised to increase strongly because of ongoing and planned road construction. If these new roads cannot be avoided, effective mitigation measures will be necessary to stop biodiversity decline. Fencing along roads effectively reduces roadkill and is often used in combination with wildlife passages. Because fencing the entire road is not always possible due to financial constraints, high-frequency roadkill areas are often identified to inform the placement of fencing. We devised an adaptive fence-implementation plan to prioritize road sections for fencing. In this framework, areas along roads of high, moderate, and low levels of animal mortality (respectively, roadkill hotspots, warmspots, and coldspots) are identified at multiple scales (i.e., in circles of different diameters [200–2000 m] in which mortality frequency is measured). Fence deployment is based on the relationship between the amount of fencing being added to the road, starting with the strongest roadkill hotspots, and potential reduction in road mortality (displayed in mortality-reduction graphs). We applied our approach to empirical and simulated spatial patterns of wildlife–vehicle collisions. The scale used for analysis affected the number and spatial extent of roadkill hot-, warm-, and coldspots. At fine scales (e.g., 200 m), more hotspots were identified than at coarse scales (e.g., 2000 m), but combined the fine-scale hotspots covered less road and less fencing was needed to reduce road mortality. However, many short fences may be less effective in practice due to a fence-end effect (i.e., animals moving around the fence more easily), resulting in a trade-off between few long and many short fences, which we call the FLOMS (few-long-or-many-short) fences trade-off. Thresholds in the mortality-reduction graphs occurred for some roadkill patterns, but not for others. Thresholds may be useful to consider when determining road-mitigation targets. The existence of thresholds at multiple scales and the FLOMS trade-off have important implications for biodiversity conservation.  相似文献   
33.
Wildlife health assessments help identify populations at risk of starvation, disease, and decline from anthropogenic impacts on natural habitats. We conducted an overview of available health assessment studies in noncaptive vertebrates and devised a framework to strategically integrate health assessments in population monitoring. Using a systematic approach, we performed a thorough assessment of studies examining multiple health parameters of noncaptive vertebrate species from 1982 to 2020 (n = 261 studies). We quantified trends in study design and diagnostic methods across taxa with generalized linear models, bibliometric analyses, and visual representations of study location versus biodiversity hotspots. Only 35% of studies involved international or cross-border collaboration. Countries with both high and threatened biodiversity were greatly underrepresented. Species that were not listed as threatened on the International Union for Conservation of Nature Red List represented 49% of assessed species, a trend likely associated with the regional focus of most studies. We strongly suggest following wildlife health assessment protocols when planning a study and using statistically adequate sample sizes for studies establishing reference ranges. Across all taxa blood analysis (89%), body composition assessments (81%), physical examination (72%), and fecal analyses (24% of studies) were the most common methods. A conceptual framework to improve design and standardize wildlife health assessments includes guidelines on the experimental design, data acquisition and analysis, and species conservation planning and management implications. Integrating a physiological and ecological understanding of species resilience toward threatening processes will enable informed decision making regarding the conservation of threatened species.  相似文献   
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Restoring species-rich tropical forests is an important activity because it helps mitigate land deforestation and degradation. However, scientific understanding of the ecological processes responsible for forest restoration is poor. We review the literature to synthesize the current state of understanding of tropical forest restoration from a biogeochemical point of view. Aboveground biomass and soil carbon accumulation of restored tropical forests are a function of age, climate, and past land use. Restored forests in wet life zones accumulate more biomass than those in moist or dry life zones. Forests restored on degraded sites accumulate less aboveground biomass than forests restored on pastures or agricultural land. Rates of aboveground biomass accumulation in restored forests are lower than during natural succession, particularly during the first decades of forest establishment. Rates of litterfall, biomass production, soil carbon accumulation, and nutrient accumulation peak during the first few decades of restored forest establishment and decline in mature stages. Changes in species composition and canopy closure influence the rate of primary productivity of older restored stands. Species composition also influences the rate and concentration of nutrient return to the forest floor. The ratio of primary productivity to biomass is high in young restored forests and low in mature stands irrespective of climate. The ratio is low when past land use has little effect on biomass accumulation, and high when past land uses depresses biomass accumulation. This effect is due to a high rate of litterfall in restored forests, which helps restore soil by circulating more nutrients and biomass per unit biomass accumulated in the stand. The degree of site degradation and propagule availability dictates the establishment and growth of tree species. Reestablishment of forest conditions and the enrichment of sites by plant and animal species invasions lead to faster rates of succession, aboveground primary productivity, and biomass accumulation in restored forests. Our review demonstrates that nutrient cycling pathways and nutrient use efficiency are critical for interpreting the suitability of tree species to different conditions in forest stands undergoing restoration.  相似文献   
36.
Food security and sustainable development require efficient use of water resources, especially in irrigation. Economic pricing can be an effective tool to achieve more efficient water use, provided it is supported by other policies in implementation. Applying various water pricing and cost recovery arrangements is suggested for efficient allocation. Any adverse impact on farmers’ incomes must be addressed and more reliable service must accompany higher prices. Experience from several countries suggests a variety of implementation issues. Essential complements to water pricing are water distribution rules and technological choices at critical nodes in the delivery system that allow farmers flexibility in conserving water in response to higher prices. Among supporting institutions, water users associations seem a higher priority than water markets.  相似文献   
37.
We hypothesized that raters' tendency to deliberately inflate performance appraisal ratings of subordinates would be associated with rater negative affectivity (NA) and two characteristics of the performance appraisal context: documentation of subordinates' work behaviors and appraisal visibility. We further hypothesized interactions among these variables, such that high‐NA, but not low‐NA raters, would be more likely to inflate ratings under conditions of low documentation and high appraisal visibility. Moreover, we predicted that NA would be associated most strongly with rating inflation when documentation was low and appraisal visibility was high, simultaneously. Results from a sample of 148 supervisors from a variety of organizations supported these hypotheses. We discuss several practical implications of the results and suggest areas for future inquiry. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
38.
Little is known about the factors that may impact on the willingness of physicians and nurses to treat patients during a bioterrorism attack. This survey was conducted among 76 randomly selected nurses and physicians in the emergency rooms of three public hospitals in order to analyse the relationship between knowledge, profession and the willingness to treat anthrax. The study finds that the willingness of physicians and nurses to come to work is 50% greater among the group with the highest knowledge about anthrax (P < 0.0001). Within that group, the willingness to treat patients suspected of being infected with anthrax was 37% greater (P < 0.0001) and the willingness to treat patients diagnosed with anthrax was 28% greater (P = 0.004) than in the other groups. These results imply that enhancement of knowledge among health care workers may improve their willingness to come to work and treat patients infected with anthrax during a bioterrorism attack.  相似文献   
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40.
Dibromoneopentyl glycol (DBNPG) is a brominated flame retardant that is used as an additive during the manufacture of plastic polymers and as a chemical intermediate for other flame retardants. It is classified as not readily biodegradable and based on experimental studies in animals is believed to be a carcinogen. We have demonstrated, to the best of our knowledge for the first time, the complete biodegradation of DBNPG under aerobic conditions. Total organic carbon (TOC) analysis indicates the complete mineralization of DBNPG. DBNPG biodegradation was accompanied by the release of bromide into the medium, probably due to a biological debromination reaction by bacterial consortia. A denaturing gradient gel electrophoresis (DGGE) analysis of PCR amplified 16S rRNA gene was used, to characterize the bacterial consortia involved in DBNPG biodegradation. At least seven bacterial species were found to be involved in this process, among them species with similarity to strains that are known for their dehalogenating ability.  相似文献   
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