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791.
Wave exposure and habitat complexity have been used to explain variations in the distribution patterns and behavior of many reef fishes. This study analyzed the influence of both factors on density and foraging activity, and the influence of group size on foraging in three species of the genus Halichoeres (Labridae) on tropical rocky shores. It was shown that initial phases (IP) and terminal phases (TP) Halichoeres, were influenced by wave exposure, although foraging in Halichoeres brasiliensis TP was not influenced by wave exposure. The IP in all three species were positively associated with rugosity and algal cover while the TP was positively associated with depth. Habitat complexity also influences foraging in these species. Group size influenced foraging activity, except in H. brasiliensis TP. We also found variations in microhabitat patches used for foraging between species and differences in the stomach contents between species and phases, showing that functional roles change in response to ontogenetic shifts.  相似文献   
792.
A study is presented on the distribution of 234U, 238U, 235U isotopes in surface water of the Llobregat river basin (Northeast Spain), from 2001 to 2006. Sixty-six superficial water samples were collected at 16 points distributed throughout the Llobregat river basin. Uranium isotopes were measured by alpha spectrometry (PIPS detectors). The test procedure was validated according to the quality requirements of the ISO17025 standard. The activity concentration for the total dissolved uranium ranges from 20 to 261 mBq L−1. The highest concentrations of uranium were detected in an area with formations of sedimentary rock, limestone and lignite. A high degree of radioactive disequilibrium was noted among the uranium isotopes. The 234U/238U activity ratio varied between 1.1 and 1.9 and the waters with the lowest uranium activity registered the highest level of 234U/238U activity ratio. Correlations between uranium activity in the tested water and chemical and physical characteristics of the aquifer were found.  相似文献   
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Non-invasive prenatal screening (NIPS) has revolutionized the approach to prenatal fetal aneuploidy screening. Many commercial providers now offer analyses for sub-chromosomal copy number variations (CNVs). Here, we review the use of NIPS in the context of screening for microdeletions and microduplications, issues surrounding the choice of disorders tested for, and the advantages and disadvantages associated with the inclusion of microdeletions to current NIPS. Several studies have claimed benefits; however, we suggest that microdeletions have not demonstrated a low enough false positive rate to be deemed practical or ethically acceptable, especially considering their low positive predictive values. Because a positive NIPS result should be confirmed using diagnostic techniques, and false positive rates are as high as 90% for some microdeletions, diagnostic testing seems preferable when the goal is to maximize the detection of microdeletion or microduplication syndromes.  相似文献   
795.
I. Lewis  S. Newnam 《Safety Science》2011,49(10):1321-1330
This paper details the development of, and perceived role and effectiveness of an innovative intervention designed to ultimately improve the safety of a group of community care (CC) nurses while driving. Recruiting participants from an Australian CC nursing car fleet, qualitative responses from a series of open-ended questions were obtained from drivers (n = 36), supervisors (n = 22), and managers (n = 6). The findings supported the effectiveness of the intervention in reducing self-reported speeding and promoting greater insight into one’s behaviour on the road. This research has important practical implications in that it highlights the value of developing an intervention based on a sound theoretical framework and which is aligned with the needs and beliefs of personnel within a particular organisation.  相似文献   
796.
Evaluation of sustainability in various facets of life is gaining increasing importance. Traditionally, different multi-criteria decision-making methods have been used for sustainability assessment. “Sustainability” can be a qualitative concept, and as such several researchers have attempted fuzzy logic for the quantitative assessment of sustainability. This paper outlines a new evaluation model based on fuzzy multi-criteria decision-making. The model is tested for sustainability assessment of higher education institutions (HEIs). It is based on a driving force–pressure–state–exposure–effect–action (DPSEEA) framework and is called uncertainty-based DPSEEA-Sustainability index Model (uD-SiM). The uD-SiM is a causality-based model in which the sustainability index is an outcome of nonlinear impacts of sustainability indicators in different stages of DPSEEA. The percent contribution of driving forces on the sustainability index of HEI is investigated using sensitivity analysis. The study reveals that education in sustainability and global and local research trends are the major driving forces for achieving sustainability in HEI, followed by financial and economic growth rate, social equity, energy requirements rate, and institutional enhancement, in descending order. The results of uD-SiM were found to be more realistic and rational than our earlier proposed approach, D-SiM.  相似文献   
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799.
1999年7月,喀麦隆的一个小农合作社Macefcoop成功地将其头两集装箱有机咖啡装运到欧洲.这是从非洲进入“公平交易”市场的第一种有机咖啡.   在坦桑尼亚,卡格拉(Kagera)区两个村庄的农民(卡格拉合作联盟的成员)最后决定转向有认证的有机生产.   也在坦桑尼亚的乞力马扎罗土著合作联盟正在从事一个试验项目工作,以在他们的一个农场上引种有机咖啡,旨在向农民们示范何谓有机以及怎样才能实施有机生产.   这三个合作社全都是Max Havelaar基金会的注册伙伴.......  相似文献   
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