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121.
Although much is known about the relationship between vigilance, group size and predation risk, behavioural responses to predation risk and their resultant costs are less clear. We investigated the response of Diana monkeys to increased predation risk by looking at behavioural changes associated with male long-distance calls, which are reliably given to certain predators. After male long-distance calls, group spread and nearest-neighbour distance decreased whilst travel and association rates for the group increased. The average height and exposure level of individuals in the group did not change after calls. Individual Diana monkeys changed their behaviour and were more likely to be vigilant or travel and less likely to engage in social or resting behaviours after long-distance calls. In addition, movement rates increased with the number of species the Diana monkeys were associated with. Diana monkey long-distance calls facilitate the joining of groups of other species. Black and white colobus and lesser spot-nosed monkeys were more likely to be in an association following a long-distance call than before. Behavioural responses, such as increased travel or association rates, that reduce foraging efficiency are interpreted as evidence of a non-lethal impact of increased predation risk.  相似文献   
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This article is a review of new and versatile optical-immunoassay instrumentation for water monitoring developed through two European Union projects, RIver ANAlyser (RIANA) and Automated Water Analyser Computer Supported System (AWACSS). Both projects utilise immunoassay techniques to isolate the analytes and Total Internal Reflection Fluorescence (TIRF) to quantify them. Completed in 1999, the RIANA project developed a sensitive and cost-effective analytical system capable of simultaneous detection of multiple-analytes in real-world water samples. The AWACSS project has been in progress since 2001 and is developing rugged-but-sensitive instrumentation that will detect up to 30 analytes simultaneously, will operate unattended, and will have networking capability.  相似文献   
124.
Summary. Detection of heterospecific predators and prey via chemical cues is well known, but only a few studies have examined the potential for such discrimination in cannibalistic systems. In newts, Notophthalmus viridescens, adults are opportunistic predators of conspecific larvae. I used a laboratory bioassay to determine whether larvae and adults distinguish between chemical stimuli from members of the different age classes. Larvae distinguished between chemical stimuli from larvae and adults by decreasing their activity only following exposure to stimuli from adults. Decreased activity is consistent with an antipredator response in many prey species, including larval newts. In contrast, adults increased their activity and increased time spent in open areas in response to stimuli from larvae, but not to stimuli from adults. Increased activity is consistent with a feeding response; adults also showed increased activity and increased time in open areas in response to chemical stimuli from familiar heterospecific prey (brine shrimp). The proximate cue that allowed the newts to distinguish between the different age classes is not associated with short-term dietary differences because all stimulus animals were fed the same prey. Stimulus strength was controlled by diluting the stimulus solutions according to the volume of the stimulus animal. Therefore, there appear to be intrinsic differences in the chemical signatures of larval and adult newts.  相似文献   
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A large number of methods and approaches that can be used for supporting waste management decisions at different levels in society have been developed. In this paper an overview of methods is provided and preliminary guidelines for the choice of methods are presented. The methods introduced include: Environmental Impact Assessment, Strategic Environmental Assessment, Life Cycle Assessment, Cost-Benefit Analysis, Cost-effectiveness Analysis, Life-cycle Costing, Risk Assessment, Material Flow Accounting, Substance Flow Analysis, Energy Analysis, Exergy Analysis, Entropy Analysis, Environmental Management Systems, and Environmental Auditing. The characteristics used are the types of impacts included, the objects under study and whether the method is procedural or analytical. The different methods can be described as systems analysis methods. Waste management systems thinking is receiving increasing attention. This is, for example, evidenced by the suggested thematic strategy on waste by the European Commission where life-cycle analysis and life-cycle thinking get prominent positions. Indeed, life-cycle analyses have been shown to provide policy-relevant and consistent results. However, it is also clear that the studies will always be open to criticism since they are simplifications of reality and include uncertainties. This is something all systems analysis methods have in common. Assumptions can be challenged and it may be difficult to generalize from case studies to policies. This suggests that if decisions are going to be made, they are likely to be made on a less than perfect basis.  相似文献   
127.
根据嘉兴电厂的实际情况,在对6种主流脱硝工艺进行技术经济分析的基础上,结合电厂近期和远期的NOx控制目标,对各种脱硝工艺的组合进行研究,推荐了可行的脱硝方案,为工程的实施提供了可靠的技术依据。  相似文献   
128.
介绍了锅炉燃烧中降低NOx的主要措施和几种国内外主要低NOx燃烧技术的脱硝原理.发展低NOx燃烧技术,对环境保护具有重大意义.  相似文献   
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130.
The chemical signals of solitary and territorial felid species are essential for their intraspecific communication. We studied the selection of plant substrates during the fecal marking behavior of the European wildcat Felis silvestris from September 2008 to June 2009 in a protected area in Northwest Spain. The aim of the study was to examine the selection of plants as signal posts with respect to their physical characteristics. We hypothesized that wildcats deposit their fecal marks on plants with physical characteristics (e.g., size, species, and visual conspicuousness) that enhance the olfactory and visual effectiveness of the signal. Our results indicate that diameter, plant group, visual conspicuousness, and interaction between the diameter and plant group influence the decision of wildcats to deposit their fecal marks on plants. The wildcats chose plants with greater diameters and greater visual conspicuousness as scent-marking posts. Moreover, the wildcats chose woody and herbaceous plants, and certain plant species were marked more frequently than expected at random. Indeed, our results indicate that the fecal marks were not randomly distributed on the plants: the wildcats chose to place their marks on plants with certain physical characteristics that maximized the detectability of the signal by intruders and potential mates, thus facilitating the spatial distribution of the species.  相似文献   
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