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61.
Summary The threespine stickleback,Gasterosteus aculeatus is a voracious cannibal of both its own eggs and those of conspecific neighbours. Females, but not males, can distinguish their progeny from those of other fish and attacked alien eggs more frequently. In experiments to examine nest raiding, females that initiated raids on nests resulting in cannibalism were the first females to spawn in the reconstructed nest. These results support the hypothesis that cannibalism by females may be adaptive in situations where intense female competition for male guardians occurs.  相似文献   
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The feasibility of a nanotechnology‐based hydrocarbon and other contaminants removal pressure filtration device has been demonstrated for dewatering industrial utility vaults and substructures for discharge to local storm drains. The use of the filter device facilitated compliance of utility companies with the General National Pollutant Discharge Elimination System (NPDES) Permit for Discharges from Utility Vaults and Substructures to Waters of the United States. The filter device, employing agglomerated oleophilic nanomaterials demonstrated the removal of dissolved priority pollutants, total suspended solids, and hexane extractable materials below U.S. Environmental Protection Agency criteria with an overall efficiency of 97.4 percent. Overall reduction per contaminant averaged 90 percent. ©2016 Wiley Periodicals, Inc.  相似文献   
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Abstract

Many processes have been investigated to dispose of obsolete pesticide stocks and clean up wastewater and contaminated soil. The processes vary in their stages of development and commercial utility. With the exception of incineration, no single process may be amenable to all pesticide waste. Thus, any chosen process must consider first the chemical constituents needing remediation, their concentration, and desired or regulated cleanup objectives. Incineration seems too impractical and expensive to clean up routinely generated wastewater and contaminated soil, but it may currently be the only practical option for obsolete stocks . Practical remediation processes for wastewater and contaminated soil produced by small waste generators are discussed. Cleanup should be viewed as an integration of physical, chemical, and biological technologies.  相似文献   
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Molting in crustaceans is an important endocrine-controlled biological process that plays a critical role in growth and reproduction. Many factors can affect this physiological cycle in crustaceans including environmental stressors and disease agents. For example the pathology of Taura Syndrome Virus (TSV) of shrimp is closely related to molting cycle. Similarly, endosulfan, a commonly used pesticide is a potential endocrine disruptor. This study explores interrelationships between pesticide exposure, virus infection and their interactions with physiology and susceptibility of the shrimp. Litopenaeus vannamei (Pacific white shrimp) were challenged with increasing doses of endosulfan and TSV (TSV-C, a Belize reference strain) to determine the respective median lethal concentrations (LC50s). The 96-h endosulfan LC50 was 5.32 μg L−1, while the 7-d TSV LC50 was 54.74 mg L−1. Subsequently, based on their respective LC50 values, a 20-d interaction experiment with sublethal concentrations of endosulfan (2 μg L−1) and TSV (30 mg L−1) confirmed a significant interaction (p < 0.05, χ2 = 5.29), and thereby the susceptibility of the shrimp. Concurrently, molt-stage of animals, both at the time of exposure and death, was compared with mortality. For animals challenged with TSV, no strong correlation between molt-stage and mortality was observed (p > 0.05). For animals exposed to endosulfan, animals in the postmolt stage were shown to be more susceptible to acute toxicity (p < 0.05). For animals exposed to both TSV and endosulfan, interference of endosulfan-associated stress lead to increasingly higher susceptibility at postmolt (p < 0.05) during the acute phase of the TSV disease cycle.  相似文献   
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The ability to examine the structure of the fetal heart in real-time started over 30 years ago now. The field has seen very great advances since then, both in terms of technical improvements in ultrasound equipment and in dissemination of operator skills. A great deal has been learnt about normal cardiac function in the human fetus throughout gestation and how it is affected by pathologies of pregnancy. There is increasing recognition of abnormal heart structure during routine obstetric scanning, allowing referral for specialist diagnosis and counselling. It is now possible to make accurate diagnosis of cardiac malformations as early as 12 weeks of gestation. Early diagnosis of a major cardiac malformation in the fetus can provide the parents with a comprehensive prognosis, enabling them to make the most informed choice about the management of the pregnancy. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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The escalating illegal wildlife trade (IWT) is one of the most high‐profile conservation challenges today. The crisis has attracted over US$350 million in donor and government funding in recent years, primarily directed at increased enforcement. There is growing recognition among practitioners and policy makers of the need to engage rural communities that neighbor or live with wildlife as key partners in tackling IWT. However, a framework to guide such community engagement is lacking. We developed a theory of change (ToC) to guide policy makers, donors, and practitioners in partnering with communities to combat IWT. We identified 4 pathways for community‐level actions: strengthen disincentives for illegal behavior, increase incentives for wildlife stewardship, decrease costs of living with wildlife, and support livelihoods that are not related to wildlife. To succeed the pathways, all require strengthening of enabling conditions, including capacity building, and of governance. Our ToC serves to guide actions to tackle IWT and to inform the evaluation of policies. Moreover, it can be used to foster dialogue among IWT stakeholders, from local communities to governments and international donors, to develop a more effective, holistic, and sustainable community‐based response to the IWT crisis.  相似文献   
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The health of populations in industrialised societies has been affected for many years by ambient air pollutants presenting a threat of chronic bronchitis and lung cancer. In the 1980s Indoor pollutants received much needed investigation to assess their hazards to health. Exposure to environmental tobacco smoke and radon is now the subject of much research and concern. This review attempts to put some perspective on lung cancer that is attributable to lifetime exposure to airborne pollutants. The view is expressed that air pollution control authorities have played and are playing a major role in health improvement.  相似文献   
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