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Male Pin-tailed Whydahs Vidua macroura copulate infrequently and terminate most courtship displays, even when females are highly receptive. Female sexual interference is aimed at preventing other females from copulating, and is nearly always successful. 相似文献
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STEVEN H. MILES 《Bioethics》2013,27(3):117-123
United States military medical ethics evolved during its involvement in two recent wars, Gulf War I (1990–1991) and the War on Terror (2001–). Norms of conduct for military clinicians with regard to the treatment of prisoners of war and the administration of non‐therapeutic bioactive agents to soldiers were set aside because of the sense of being in a ‘new kind of war’. Concurrently, the use of radioactive metal in weaponry and the ability to measure the health consequences of trade embargos on vulnerable civilians occasioned new concerns about the health effects of war on soldiers, their offspring, and civilians living on battlefields. Civilian medical societies and medical ethicists fitfully engaged the evolving nature of the medical ethics issues and policy changes during these wars. Medical codes of professionalism have not been substantively updated and procedures for accountability for new kinds of abuses of medical ethics are not established. Looking to the future, medicine and medical ethics have not articulated a vision for an ongoing military‐civilian dialogue to ensure that standards of medical ethics do not evolve simply in accord with military exigency. 相似文献
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Ian PG Marshall Dusty RV Berggren Mohammad F Azizian Luke C Burow Lewis Semprini Alfred M Spormann 《The ISME journal》2012,6(4):814-826
We developed a broad-ranging method for identifying key hydrogen-producing and consuming microorganisms through analysis of hydrogenase gene content and expression in complex anaerobic microbial communities. The method is based on a tiling hydrogenase gene oligonucleotide DNA microarray (Hydrogenase Chip), which implements a high number of probes per gene by tiling probe sequences across genes of interest at 1.67 × –2 × coverage. This design favors the avoidance of false positive gene identification in samples of DNA or RNA extracted from complex microbial communities. We applied this technique to interrogate interspecies hydrogen transfer in complex communities in (i) lab-scale reductive dehalogenating microcosms enabling us to delineate key H2-consuming microorganisms, and (ii) hydrogen-generating microbial mats where we found evidence for significant H2 production by cyanobacteria. Independent quantitative PCR analysis on selected hydrogenase genes showed that this Hydrogenase Chip technique is semiquantitative. We also determined that as microbial community complexity increases, specificity must be traded for sensitivity in analyzing data from tiling DNA microarrays. 相似文献