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461.
Contact pheromones mediate mate recognition and play important roles in mating systems of longhorned beetles (Coleoptera: Cerambycidae). One common bioassay of contact chemoreception in cerambycids involves presenting a freeze-killed female to a male in a Petri dish arena. If the male attempts to mate with the female carcass, it confirms that mate recognition signals are present and intact and behavior is not involved. Cuticular hydrocarbons are then stripped from the female with successive solvent washes, rendering her unattractive to males and also resulting in a crude extract containing the cuticular hydrocarbons. To test the bioactivity of the crude extract, the same female is then treated with the extract and presented again to the male. Males of some species, including Megacyllene robiniae (F?rster), respond less readily to reconstituted females than to those same beetles before they were solvent-extracted. In the present study, we test the hypothesis that the contact pheromone of M. robiniae, Z9:C25, exists as a layer on the surface of the epicuticle. We used solid phase microextraction (SPME) to sample cuticular hydrocarbons of female beetles after they were freeze-killed, solvent washed, and treated with crude cuticular extracts. We found that extracting cuticular hydrocarbons from females and applying the resulting crude extract back onto the solvent-washed cadaver scrambles the wax layer and decreases the abundance of the contact pheromone presented on the surface of the insect.  相似文献   
462.
Increasing threats to deep-sea corals highlight the need to expand knowledge of these taxa so that conservation measures can be developed. The present study focused on the reproductive patterns of the deep-sea solitary coral Flabellum angulare. A series of samples (n = 398) collected in 2006–2008 in the northwest Atlantic at depths of 925–1,430 m revealed that gametogenesis was synchronous among males and females and fluctuated seasonally. Initiation of gamete synthesis was estimated to be in August–September and spawning in June. Further analysis and daily monitoring of 30–60 individuals maintained in a flow-through mesocosm showed that gamete release occurred in March–June with a peak in May. Release of oocytes coincided with rising seawater temperatures and high deposition rates indicative of elevated water column productivity. Oocytes (900–1,200 μm diameter) were released through the oral cavity, generally in bundles of 3–5 surrounded by mesenterial filaments and attached to a thread (30–50 mm long). As oocytes became free in the water column, ovulation occurred followed by fertilization. Eggs/embryos initially remained on the tentacles of the spawner before either falling onto the substratum or floating to the surface. The embryos developed into planula larvae measuring 2–3 mm in length within about 24 h. Together, these findings shed new light on the strategies used by deep-sea corals to maximize their reproductive success.  相似文献   
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Environmental changes can bear upon the environmental virtues, having effects not only on the conditions of their application but also altering the concepts themselves. I argue that impending radical changes in global climate will likely precipitate significant changes in the dominate world culture of consumerism and then consider how these changes could alter the moral landscape, particularly culturally thick conceptions of the environmental virtues. According to Jonathan Lear, as the last principal chief of the Crow Nation, Plenty Coups exhibited the virtue of “radical hope,” a novel form of courage appropriate to a culture in crisis. I explore what radical hope may look like today, arguing how it should broadly affect our environmental character and that a framework for future environmental virtues will involve a diminished place for valuing naturalness as autonomy from human interference.  相似文献   
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An extra small chromosome detected in amniotic fluid was identified as the product of a translocation [46,XX,t(9;15)(p24;q11.2)]. This case is unusual in that individuals with the unbalanced karyotype resulting from a 3:1 disjunction are phenotypically normal.  相似文献   
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Sustainable engineering is a conceptual and practical challenge to all engineering disciplines. Although the profession has experience with environmental dimensions of engineering activities that in some cases are quite deep, extending the existing body of practice to sustainable engineering by including social and cultural domains is a significant and non-trivial challenge. Nonetheless, progress is being made, as a recent study undertaken by the Center for Sustainable Engineering in the United States demonstrates.
Brad AllenbyEmail:
  相似文献   
470.
Environmental justice theory postulates that communities that predominately consist of minorities and those of a lower socioeconomic status are compelled to bear a disproportionate distribution of burdens resulting from land use decisions. In this article, we present a case study of West Moberly First Nations (an Indigenous group) in British Columbia, Canada, and their fight to protect a threatened herd of caribou from coal mining activities. We examine the role of caribou in maintaining the First Nations’ cultural integrity and the adverse effects of several decisions made by the Provincial Government of British Columbia that would allow a mining company to destroy the critical habitat of the species. Analysis shows that the decisions negate federal law, disregard the best available scientific and traditional knowledge, and fail to uphold the constitutional and treaty rights of the First Nation to meaningfully exercise its cultural practices and customs. A disproportionate share of environmental burdens was therefore placed onto the shoulders of the First Nation while the interests of the government and the mining industry were protected. We conclude that the decisions are a clear case of intentional environmental injustice on the part of the British Columbia government.  相似文献   
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