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<正>July 17,2014 marks the date of the brutal and unforgivable shooting down of Malaysian Airlines flight MH17 over the Ukraine,resulting in the death of all its passengers,including my longstanding friends and colleagues Joep Lange and Jacqueline van Tongeren.They were on their way to attend the 20th International Aids Conference,held this year in Melbourne,Australia.I myself had already arrived in Mel-  相似文献   
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Mating systems are a central component in the evolution of animal life histories and in conservation genetics. The patterns of male reproductive skew and of paternal shares in batches of offspring, for example, affect genetic effective population size. A prominent characteristic of mating systems of sea turtles seem to be a considerable intra- and interspecific variability in the degree of polyandry. Because of the difficulty of observing the mating behaviour of sea turtles directly in the open sea, genetic paternity analysis is particularly useful for gaining insights into this aspect of their reproductive behaviour. We investigated patterns of multiple paternity in clutches of loggerhead sea turtles in the largest Mediterranean rookery using four highly variable microsatellite loci. Furthermore, we tested for a relationship between the number of fathers detected in clutches and body size of females. More than one father was detected in the clutches of 14 out of 15 females, with two clutches revealing the contribution of at least five males. In more than half the cases, the contributions of different fathers to a clutch did not depart from equality. The number of detected fathers significantly increased with increasing female body size. This relationship indicates that males may prefer to mate with large, and therefore productive, females. Our results suggest that polyandry is likely to increase effective population size compared to a population in which females would mate with only one male; male reproductive contributions being equal.  相似文献   
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Copper-based epoxy and ablative antifouling painted panels were exposed in natural seawater to evaluate environmental loading parameters. In situ loading factors including initial exposure, passive leaching, and surface refreshment were measured utilizing two protocols developed by the US Navy: the dome method and the in-water hull cleaning sampling method. Cleaning techniques investigated included a soft-pile carpet and a medium duty 3M? pad for fouling removal. Results show that the passive leach rates of copper peaked three days after both initial deployment and cleaning events (CEs), followed by a rapid decrease over about 15 days and a slow approach to asymptotic levels on approximately day 30. Additionally, copper was more bioavailable during a CE in comparison to the passive leaching that immediately followed. A paint life cycle model quantifying annual copper loading estimates for each paint and cleaning method based on a three-year cycle of painting, episodic cleaning, and passive leaching is presented.  相似文献   
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正TYPES OF ARTICLES●FORMATS OF ARTICLES●HOW TO SUBMIT A MANUSCRIPT●PUBLICATION FEES●TYPES OF ARTICLES1.Research articles Research articles belong to the full length article type,and should include elements as follows:title,running title,and byline;correspondent footnote;abstract;introduction;materials and methods;results;discussion;acknowledgements;author contributions;references;figure legends and figures/tables.The article length should not exceed 6,000 words,and detailed requirements are in the  相似文献   
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<正>GENERAL INFORMATION World Journal of Stem Cells(World J Stem Cells,WJSC,online ISSN1948-0210,DOI:10.4252),is a peer-reviewed open access(OA)academic journal that aims to guide clinical practice and improve diagnostic and therapeutic skills of clinicians.Aims and scope WJSC covers topics concerning all aspects of stem cells:embryonic,neural,hematopoietic,mesenchymal,tissue-specific,and cancer  相似文献   
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丹江口水库淅川库区大气氮湿沉降特征   总被引:7,自引:1,他引:6  
大气氮沉降是除河流输入外水库水体重要的外源氮输入途径。以丹江口水库淅川库区为研究区,于2018年11月至2019年10月在库区周边设置了6个采样点,采集并分析了库区大气氮湿沉降样品,探讨氮湿沉降的时空分布特征以及对水库水体外源氮输入的贡献。研究结果表明,研究区大气氮湿沉降量为24.21 kg hm-2 a-1,其中氨氮占比(47.45%)为最大,有机氮占比(36.34%)次之,硝氮占比(16.21%)最小。硝氮湿沉降量在空间上表现出显著差异性。氨氮、有机氮湿沉降量的季节差异显著,氨氮是以夏季最高,秋季次之,冬季最低,而有机氮是以秋季最高,夏季次之,冬季最低。氨氮、硝氮、有机氮湿沉降量之间存在显著相关性,氨氮、有机氮湿沉降量与降水量之间存在显著相关性。总氮、氨氮湿沉降量分别为1321.98 t/a和627.34 t/a,分别占河流总氮、氨氮入库量的10.82%、34.85%。研究结果可为探索有针对性的库区水体氮污染控制途径提供重要理论基础。  相似文献   
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Wherever individuals perform cooperative behaviours, each should be selected to adjust their own current contributions in relation to the likely future contributions of their collaborators. Here, we use the sentinel system of pied babblers (Turdoides bicolor) to show that individuals anticipate contributions by group mates, adjusting their own contribution in response to information about internal state broadcast by others. Specifically, we show that (i) short-term changes in state influence contributions to a cooperative behaviour, (ii) individuals communicate short-term changes in state, and (iii) individuals use information about the state of group mates to adjust their own investment in sentinel behaviour. Our results demonstrate that individual decisions about contributions to a cooperative effort can be influenced by information about the likely future contribution of others. We suggest that similar pre-emptive adjustments based on information obtained from collaborators will be a common feature of cooperative behaviour, and may play an important role in the development of complex communication in social species.  相似文献   
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The contributions of Carl Durney to dosimetry have decisively advanced the bioelectromagnetics field and led to significant revisions of relevant health standards. Three items come to mind while studying his work: 1. The work of Carl Durney and his colleagues in dosimetry has advanced the bioelectromagnetics field most significantly whereas more abundant work of a biomedical nature has had less impact. More biophysics work is desirable. 2. The rationale for the specific absorption rate as a basis of health standards needs further elaboration. The need for scaling animal results is stressed. 3. Dosimetry at the cellular level (microdosimetry) is essential if one cares to discuss direct field interactions at the cellular and macromolecular level. Carl Durney's recognition of this need is stated. Carl Durney's wide range of productive interests is indicated by several tables. They summarize his many contributions to electrical engineering, education, bioelectromagnetic dosimetry, hyperthermia, NMR, and field‐induced biophysical phenomena at the molecular and cellular level. His scientific work is summarized, including how his interest changed with time. His scientific accomplishment and productive interaction with students, colleagues, and society sets an example to be admired. Bioelectromagnetics 20:3–8, 1999. © 1999 Wiley‐Liss, Inc.  相似文献   
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