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81.
The extent of electromagnetic interference (EMI) from 16.7-Hz alternate current power lines in the human surface electrocardiogram (ECG) was evaluated. Results showed a direct linear correlation between mean EMI and magnetic induction of 5.8-21 microT on a railroad platform (electric field: 270 V/m). EMI inside a railroad car (10 microT, 0 V/m) was comparable to the electromagnetic field at the platform. Inside a voltage transformer substation (0 microT, 2000 V/m) EMI occurred only when the ECG device was closer to the power line than the test person. Magnetic induction caused 16.7-Hz EMI to a degree that proper diagnosis of ECG-rhythms was rendered impossible.  相似文献   
82.
Rogers W  Ballantyne A  Draper H 《Bioethics》2007,21(9):520-524
In this paper we argue that sex-selective abortion (SSA) cannot be morally justified and that it should be prohibited. We present two main arguments against SSA. First, we present reasons why the decision for a woman to seek SSA in cultures with strong son-preference cannot be regarded as autonomous on either a narrow or a broad account of autonomy. Second, we identify serious harms associated with SSA including perpetuation of discrimination against women, disruption to social and familial networks, and increased violence against women. For these reasons, SSA should be prohibited by law, and such laws should be enforced. Finally, we describe additional strategies for decreasing son-preference. Some of these strategies rely upon highlighting the disadvantages of women becoming scarce, such as lack of brides and daughters-in-law to care for elderly parents. We should, however, be cautious not to perpetuate the view that the purpose of women is to be the consorts for, and carers of, men, and the providers of children. Arguments against SSA should be located within a concerted effort to ensure greater, deeper social and cultural equality between the sexes.  相似文献   
83.
重大工程建设项目竣工验收工作中的环境监测   总被引:1,自引:0,他引:1  
耿晓梅 《生态学杂志》2007,26(7):1129-1132
以辽宁省环境监测中心站配合国家环境保护总局评估中心进行的金哨水利枢纽工程竣工环境保护验收调查为例,论述了环境监测在重大工程建设项目验收调查中的重要作用,提出了项目验收监测工作的程序,认为重大工程建设项目的监测从项目开始就应列入计划,通过监测与监督,使施工期的环境污染问题降至最低限度,这样才能更好地保护生态环境及周围公众的安全健康.  相似文献   
84.
Reconnaissance and latent learning in ants   总被引:6,自引:0,他引:6  
We show that ants can reconnoitre their surroundings and in effect plan for the future. Temnothorax albipennis colonies use a sophisticated strategy to select a new nest when the need arises. Initially, we presented colonies with a new nest of lower quality than their current one that they could explore for one week without a need to emigrate. We then introduced a second identical low quality new nest and destroyed their old nest so that they had to emigrate. Colonies showed a highly significant preference for the (low quality) novel new nest over the identical but familiar one. In otherwise identical experiments, colonies showed no such discrimination when the choice was between a familiar and an unfamiliar high-quality nest. When, however, either all possible pheromone marks were removed, or landmarks were re-orientated, just before the emigration, the ants chose between identical low-quality new nests at random. These results demonstrate for the first time that ants are capable of assessing and retaining information about the quality of potential new nest sites, probably by using both pheromones and landmark cues, even though this information may only be of strategic value to the colony in the future. They seem capable, therefore, of latent learning and, more explicitly, learning what not to do.  相似文献   
85.
The traditional medical model of health and health policy development has focused on individuals and the role of medical care in preventing and treating disease and injury. Recent attention to health inequities and social determinants of health has raised the profile of population heath and evidence-based strategies for improving the health of whole populations. At the same time, risk science has emerged as an important new discipline for the assessment and management of risks to health. This article reviews historical developments in the fields of risk management and population health and proposes a joint population health risk management framework that integrates the key elements of both fields. Applying this integrated approach to managing population health risks will facilitate the development of evidence-based health policy. It will encourage a more systematic and comprehensive evaluation of population health issues and promote the use of a broader suite of interventions to reduce health risks and enhance population health status.  相似文献   
86.
Because hunting disturbance can influence local distribution of ducks and their availability to hunters, managers often limit access to hunting areas to improve hunting success and satisfaction. Few studies have quantified the effectiveness of public area access restrictions on duck hunter activity, harvest, or hunters' satisfaction with their hunting experience. We used a cross-over design over 6 consecutive hunting seasons (2008–2009 through 2013–2014) on State Wildlife Areas (SWAs) in northeastern Colorado, USA, to compare the effects of restricted hunting access regulations and regulations without these restrictions on duck hunter activity, harvest success, harvest levels, and satisfaction. We also considered effects of SWA types, duck abundance, temperature, precipitation, use of equipment by duck hunting parties, and, for hunter satisfaction, hunting success, hunting parties' satisfaction with ducks seen, habitat conditions, crowding from other hunters, and SWA regulations. The number of days when duck hunters had access to restricted properties was about half that on unrestricted properties, and unrestricted properties were used by about twice as many duck hunting parties, but the mean number of hunting parties per available hunting day and mean party size were similar under the 2 types of regulations. Most (56%) duck hunting parties did not bag any ducks; hunting success (harvest of ≥1 duck by a hunting party) was best explained by a model that included a regulation type × hunting season interaction, a SWA type × month interaction, hunter density the previous day, an index of hunter investment (number of decoys used and whether dogs and calls were used), and temperature. Successful hunting parties harvested 1.92 ± 1.60 (SD) ducks/hunter/day (range = 0.1–7.0); the best model predicting the number of ducks harvested per hunter in successful parties included a regulation type × hunting season interaction, a SWA type × month interaction, hunter density the previous day, an index of hunter investment, temperature, and precipitation. Overall satisfaction of duck hunting parties with a day's hunt averaged 3.62 ± 1.20 based on a rank scale of 1 (very unsatisfied) to 5 (very satisfied), and was best explained by a model that included hunting party success; hunter investment; temperature; and satisfaction with duck numbers, habitat conditions, hunting regulations, and crowding. While greatly reducing days available for hunting, access restrictions were associated with improved chances of hunting parties successfully harvesting ≥1 duck in 5 of 6 hunting seasons, and substantially greater numbers of ducks harvested by hunters in successful parties in 1 of 6 hunting seasons. Restrictions did not have a strong direct effect on hunting parties' satisfaction with a day's hunt. Uncontrolled factors, including weather and use of equipment by hunters, had important influences on hunter success, harvest, and satisfaction. Managers should carefully assess hunting activity, hunter expectations and desires, and hunting area characteristics when considering access restrictions on public hunting areas.  相似文献   
87.
Several countries have imposed bans on the wearing of face veils, a controversial option considered in Bill 94 by the province of Quebec in 2010. This paper examines non-Muslim women's support for the acceptability of the niqab in public spaces. Analysing the 2010 Quebec Women's Political Participation Survey, we find that key feminist arguments – that wearing the niqab is a woman's free choice, a matter of freedom of religion and a visible symbol of women's oppression – are important drivers of opinion. Their role in shaping opinion, however, is complex and mirrors divisions among feminist groups in the province. Additional attitudinal drivers include generation, exposure to the practice and openness to immigration. Equally important, our findings suggest that being a member of a racial minority, feelings of cultural insecurity and religiosity are of little consequence for thinking on the issue.  相似文献   
88.
Recent anthropogenic increases in algal turbidity in aquatic habitats have been suggested to affect the ability of fish to assess predation risk. We investigated the response of feeding three‐spined sticklebacks (Gasterosteus aculeatus) exposed to a sudden appearance of an avian predator (the silhouette of common tern, Sterna hirundo), under clear and turbid water conditions. As stickleback use social cues to aid in predator avoidance, we also tested whether turbidity affected social information use by manipulating group size. We found that in turbid water, a smaller proportion of fish would escape from the feeding area, that the distance escaped was shorter and that a smaller proportion of fish fled into shelter. Larger group size was associated with longer escape distance and greater shelter use. However, there was no effect of group size on the proportion of fish that escaped the arena. The effect of group size was similar for turbid and clear water. Our finding that the fish showed a weaker antipredator response suggests that turbidity impedes their risk assessment capability. However, the sticklebacks were still able to benefit of the social facilitation provided by being in a group. This suggests that algal turbidity has detrimental effects on the ability of sticklebacks to assess predation risk from avian predators in shallow water. An implication is that in shallow water fish may be more vulnerable to avian predation under turbid conditions.  相似文献   
89.
目前,我国大部分公立医院尚未广泛开展内部项目支出预算绩效评价工作。随着财政部与国家卫生和计划生育委员会的预算项目绩效管理的深入开展,公立医院通过加强多部门的合作,以战略发展为导向开展项目支出预算绩效评价工作对提高资金使用效益具有重要意义。  相似文献   
90.
Natural cooperative systems take many forms, ranging from one‐dimensional cyanobacteria arrays to fractal‐like biofilms. We use in silico experimental systems to study a previously overlooked factor in the evolution of cooperation, physical shape of the population. We compare the emergence and maintenance of cooperation in populations of digital organisms that inhabit bulky (100 × 100 cells) or slender (4 × 2500) toroidal grids. Although more isolated subpopulations of secretors in a slender population could be expected to favor cooperation, we find the opposite: secretion evolves to higher levels in bulky populations. We identify the mechanistic explanation for the shape effect by analyzing the lifecycle and dynamics of cooperator patches, from their emergence and growth, to invasion by noncooperators and extinction. Because they are constrained by the population shape, the cooperator patches expand less in slender than in bulky populations, leading to fewer cooperators, less public good secretion, and generally lower cooperation. The patch dynamics and mechanisms of shape effect are robust across several digital cooperation systems and independent of the underlying basis for cooperation (public good secretion or a cooperation game). Our results urge for a greater consideration of population shape in the study of the evolution of cooperation across experimental and modeling systems.  相似文献   
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