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181.
Williams G 《Bioethics》2012,26(8):422-430
This paper considers the often-expressed fear that medical research may use children merely as means, and not respect them as ends in themselves - especially insofar as they are deemed less able to consent than adults. The main focus is on large-scale genetic, socio-medical and epidemiological research. The theoretical starting point of the paper is that to be treated as an end in oneself is to be regarded as - and to act as - a participant in cooperative endeavours. This participatory status is certainly connected with individual authority to consent and dissent; and there is no doubt that consent plays an important role when adults participate in many research projects. However, insofar as consent is located within structures of human cooperation, the authority to consent is not a straightforward privilege. Rather, consent is bound up with responsibility for one's choices and commitment to shared terms of cooperation. Given this understanding, it is argued that consent should not be our principal concern when we involve children in research. This is not because of children's (possible) incompetence to consent as such, but rather because children are still learning how to respect and assess the cooperative terms involved in our institutional lives. Instead, our leading concern should be with the terms regulating their involvement in research. Given suitable safeguards, research is one way in which children may learn what it is to bear responsibilities and to act as an end in oneself - that is, to cooperate with others on reasonable terms and for worthy ends.  相似文献   
182.
Sharp R 《Bioethics》2012,26(5):231-235
Some writers have argued that a Kantian approach to ethics can be used to justify suicide in cases of extreme dementia, where a patient lacks the rationality required of Kantian moral agents. I worry that this line of thinking may lead to the more extreme claim that euthanasia is a proper Kantian response to severe dementia (and similar afflictions). Such morally treacherous thinking seems to be directly implied by the arguments that lead Dennis Cooley and similar writers to claim that Kant might support suicide. If rationality is the only factor in valuing a human life, then the loss of that rationality (however such loss might be defined) would allow us to use essentially utilitarian thinking in order to support non-voluntary euthanasia, since the patients themselves would no longer be moral agents that demand respect.  相似文献   
183.
doi: 10.1111/j.1741‐2358.2011.00540.x Assessing the oral health of an ageing population: methods, challenges and predictors of survey participation Objectives: To examine predictors of participation and to describe the methodological considerations of conducting a two‐stage population‐based oral health survey. Methods: An observational, cross‐sectional survey (telephone interview and clinical oral examination) of community‐dwelling adults aged 45–64 and ≥65 living in Nova Scotia, Canada was conducted. Results: The survey response rate was 21% for the interview and 13.5% for the examination. A total of 1141 participants completed one or both components of the survey. Both age groups had higher levels of education than the target population; the age 45–64 sample also had a higher proportion of females and lower levels of employment than the target population. Completers (participants who completed interview and examination) were compared with partial completers (who completed only the interview), and stepwise logistic regression was performed to examine predictors of completion. Identified predictors were as follows: not working, post‐secondary education and frequent dental visits. Conclusion: Recruitment, communications and logistics present challenges in conducting a province‐wide survey. Identification of employment, education and dental visit frequency as predictors of survey participation provide insight into possible non‐response bias and suggest potential for underestimation of oral disease prevalence in this and similar surveys. This potential must be considered in analysis and in future recruitment strategies.  相似文献   
184.
著: 《生物信息学》2019,26(5):41-47
历史性文化景观要素塑造了如今的景观“面孔”。在当前的规划框架下,对其保护和评价工作,也只可能在对其概念足够理解的情况下,借助于数字化手段得以实现。在此背景下,自1999年起,在德国开始建立一个基于志愿行为的文化景观要素收集系统——“KLEKs”。其目的:尽可能详细和全覆盖地收集基于GIS数据的历史性文化景观要素。目前,这样的系统正在被德国的几个州使用,特别是借助于乡村研究方面的专家和志愿者参与,并在德国几所大学的教学和研究工作的支持下得以推进。通过KLEKs系统的时间顺序发展、收集方法、数据库建立,以及用于规划应用的多角度,概述了KLEKs系统的发展。  相似文献   
185.
The number of waterfowl hunters in the United States has declined since the 1980s despite relatively abundant waterfowl populations and liberal hunting regulations. Programs focused on recruiting, retaining, and reactivating (R3) waterfowl hunters have become important to avoid further losses in traditional revenue for habitat management and protection and political support for waterfowl conservation and management. We focus on 4 waterfowl hunter population vital rates (i.e., recruitment rate, retention probability, license purchase probability, realized population growth rate), which can be used to improve the effectiveness of waterfowl hunter R3 activities and initiatives by providing a deeper understanding of waterfowl hunter population dynamics to determine who programs should target, where programs should be targeted, and finally the evaluation of programs. To do so, we analyzed Nebraska state electronic license data from 2012–2019 using Pradel survival and recruitment models in a mark-recapture framework. Female waterfowl hunter recruitment was higher than males; however, retention and license purchase probabilities were lower. Recruitment was highest in younger generations and retention highest in older generations. License purchase probabilities were highest among those in the oldest and youngest generations. The availability of hunting opportunity increased license purchase probabilities but had a minimal influence on retention and no association with recruitment. There were weak relationships between rurality and recruitment, and retention and license purchase probabilities. Finally, belonging to Ducks Unlimited was positively associated with higher license purchase and retention probabilities. Targeting an increase in license purchase probability by promoting social support for hunters through conservation organization membership should be a focus of waterfowl hunter R3 efforts to have the greatest influence on increasing waterfowl hunter participation.  相似文献   
186.
The risk of cardiovascular disease (CVD) increases in post-menopausal women, yet, the role of exercise, as a preventative measure for CVD risk in post-menopausal women has not been adequately studied. Accordingly, we investigated the impact of voluntary cage-wheel exercise and forced treadmill exercise on cardiac adaptation in menopausal mice. The most commonly used inducible model for mimicking menopause in women is the ovariectomized (OVX) rodent. However, the OVX model has a few dissimilarities from menopause in humans. In this study, we administered 4-vinylcyclohexene diepoxide (VCD) to female mice, which accelerates ovarian failure as an alternative menopause model to study the impact of exercise in menopausal mice. VCD selectively accelerates the loss of primary and primordial follicles resulting in an endocrine state that closely mimics the natural progression from pre- to peri- to post-menopause in humans. To determine the impact of exercise on exercise capacity and cardiac adaptation in VCD-treated female mice, two methods were used. First, we exposed a group of VCD-treated and untreated mice to a voluntary cage wheel. Second, we used forced treadmill exercise to determine exercise capacity in a separate group VCD-treated and untreated mice measured as a tolerance to exercise intensity and endurance.  相似文献   
187.

[Purpose]

To examine the effects of active drinking practices on fluid consumption and sweat rate while exercising in a hot environment.

[Methods]

Nine men completed two experiments. Each consisted of 3 phases: pre-testing (pre), training period, and post-testing (post). During testing, the subjects ran on a treadmill at a moderate intensity for 90 min at 39 ± 1℃ followed by a 3-h recovery. They drank ad libitum. During training, they ran for 90 min for 7 days while either drinking actively (AH, 150% of weight loss) or passively (PH, 50% of weight loss).

[Results]

The actual volume consumed in training was three times greater during AH than during PH. In post during AH, the volume of drinking was two times greater than pre (1592 ± 953 and 855 ± 551 mL, respectively; p < 0.05). No difference in volume consumption during PH between pre and post was found. The sweat loss during exercise was greater in post (1377 ± 956 mL) than in pre (558 ± 642 mL) during AH (p < 0.05), but not during PH. Rectal temperature and heart rate decreased after training. Serum osmolality following exercise were not different than the baseline or between the conditions.

[Conclusion]

Active drinking practices while exercising in a hot environment induced greater voluntary fluid intake and sweat loss.  相似文献   
188.
Objective: To describe the relationship between obesity class and workforce participation and the influence of demographic, socioeconomic, and comorbid disease states on this relationship using population‐based Canadian data. Research Methods and Procedures: Responses from 73, 531 adults surveyed in the Canadian Community Health Survey 2000 to 2001 who provided complete information regarding variables of interest were analyzed. Workforce participation was defined as individuals reporting that they held and were present at a job or business in the week before survey administration. The association between obesity and workforce participation was explored using logistic regression after adjusting for demographic, socioeconomic, and obesity‐related comorbidities. Results: In univariate analysis, obese individuals had lower odds of participating in the workforce. In the fully adjusted model, increasing obesity was associated with decreasing odds of workforce participation, with Class I, II, and III obesity having odds ratios (95% confidence interval) of 0.94 (0.89 to 0.99), 0.85 (0.77 to 0.94), and 0.66 (0.57 to 0.78), respectively. Obese individuals were also less likely to be employed and more likely to be absent from work. Discussion: Obesity is associated with lower workforce participation. This association appears to be independent of associated comorbidity and sociodemographic factors. These results indicate that the economic impact of obesity alone on workforce productivity is larger than previous reports suggest.  相似文献   
189.
In eusocial organisms, some individuals specialize in reproduction and others in altruistic helping. The evolution of eusociality is, therefore, also the evolution of remarkable inequality. For example, a colony of honeybees (Apis mellifera) may contain 50 000 females all of whom can lay eggs. But 100 per cent of the females and 99.9 per cent of the males are offspring of the queen. How did such extremes evolve? Phylogenetic analyses show that high relatedness was almost certainly necessary for the origin of eusociality. However, even the highest family levels of kinship are insufficient to cause the extreme inequality seen in e.g. honeybees via ‘voluntary altruism’. ‘Enforced altruism’ is needed, i.e. social pressures that deter individuals from attempting to reproduce. Coercion acts at two stages in an individual''s life cycle. Queens are typically larger so larvae can be coerced into developing into workers by being given less food. Workers are coerced into working by ‘policing’, in which workers or the queen eat worker-laid eggs or aggress fertile workers. In some cases, individuals rebel, such as when stingless bee larvae develop into dwarf queens. The incentive to rebel is strong as an individual is the most closely related to its own offspring. However, because individuals gain inclusive fitness by rearing relatives, there is also a strong incentive to ‘acquiesce’ to social coercion. In a queenright honeybee colony, the policing of worker-laid eggs is very effective, which results in most workers working instead of attempting to reproduce. Thus, extreme altruism is due to both kinship and coercion. Altruism is frequently seen as a Darwinian puzzle but was not a puzzle that troubled Darwin. Darwin saw his difficulty in explaining how individuals that did not reproduce could evolve, given that natural selection was based on the accumulation of small heritable changes. The recognition that altruism is an evolutionary puzzle, and the solution was to wait another 100 years for William Hamilton.  相似文献   
190.
基于农牧民响应的阿拉善荒漠复合生态系统管理研究   总被引:1,自引:0,他引:1  
贾举杰  王也  刘旭升  李锋  张象枢 《生态学报》2017,37(17):5836-5845
内蒙古草原是我国华北、东北地区的重要生态屏障,阿拉善盟的生态环境直接影响到首都和华北地区的生态安全。以内蒙古自治区阿拉善盟1980—2014年年际人口、温度、家畜量及农作物面积变化为基础,2015年9月—2016年4月,采用入户访问和半结构访谈的方式,对阿拉善盟3个旗的16个自然村进行问卷调查,分析被访问对象对本区域政府-NGO-农牧民等利益相关者多方参与的荒漠化治理模式的响应和认知,以及对未来生态环境治理的建议和意愿,以期为荒漠复合生态系统的建设提供管理建议。运用The R Programming Language中的探索性因子分析法进行数据分析,结果表明:(1)自然因素(干旱、虫鼠害等)和人为因素(工业增加、城市扩张、农业增加等)是基于访谈对象认知的本区域环境恶化的主要原因。(2)多年来,政府部门主导的生态补偿和生态移民等政策的实施,政府、NGO、农牧民的群策群力以及农牧民环保意识的增强等综合因素是研究区环境局部恢复的主要原因。未来,建议加快生态建设步伐,构建以"政府主导,社会行动,社区参与"为主导的荒漠化治理模式是阿拉善环境保护和可持续发展的需要。  相似文献   
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