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81.
美国从1981年启用第一个BIT范本,之后历经数次修订,形成不同版本。其中的环境保护条款从无到有、从简到繁,2012年版本对环境保护又有大力强化。虽然环境例外条款具有法律形态,但因其为缔约方保留环境规制的空间,没有消极影响,其他环境条款尤其专门环境条款则只具有政策形态,对缔约方只有倡导和督促作用,因而也不具有负面意义。基于此,对于中美BIT谈判,中国应该持有像实践WTO规则一样的心态,研究它、接受它,为投身国际实践走出第一步,为将来参与更大范围的规则制定做好准备。  相似文献   
82.
Lack of data on daily inhalation rate and activity of children has been an issue in health risk assessment of air pollutants. This study aimed to obtain the daily inhalation rate and intensity and frequency of physical activity in relation to the environment in Japanese preschool children. Children aged four–six years (n= 138) in the suburbs of Tokyo participated in this study, which involved three days' continuous monitoring of physical activity using a tri‐axial accelerometer and parent's completion of a time/location diary during daily life. The estimated three‐day mean daily inhalation rate (body temperature, pressure, saturated with water vapor) was 9.9 ± 1.6 m3/day (0.52 ± 0.09 m3/kg/day). The current daily inhalation rate value of 0.580 m3/kg/day proposed for use in health risk assessment in Japan is confirmed to be valid to calculate central value of inhaled dose of air pollutants in five‐ to six‐year‐old children. However, the 95th percentile daily inhalation rate of 0.83 m3/kg/day based on measurement for five‐year‐old children is recommended to be used to provide an upper bound estimate of exposure that ensure the protection of all five‐ to six‐year‐old children from the health risk of air pollutants. Children spent the majority of their time in sedentary and light level of physical activity (LPA) when indoors, while 85% of their time when outdoors was spent in LPA and moderate‐to‐vigorous physical activity. The results suggest the need to consider variability of minute respiratory ventilation rate according to the environment for more refined short‐term health risk assessment.  相似文献   
83.
Schoemaker J, Twikirize J. A life of fear: sex workers and the threat of HIV in Uganda The way individuals perceive their risk to certain threats influences their adoption of preventive behaviour. This study explored sex workers' perception of risk of HIV infection within the context of other serious threats. The study was carried out in Kampala, Uganda, using peer ethnography. Sex workers were well aware of their risk of HIV infection but this risk was eclipsed by other more immediate and frightening threats. Sex workers' willingness to gamble with HIV is explained by the fact that their existence is already very dangerous, and taking risks is an inherent part of their trade. Decriminalising sex work could make their lives somewhat safer, motivating them to better protect themselves, but this is unlikely to happen in Uganda. Attempting to enforce some coercive control mechanisms would not work, given the pervasive corruption in law enforcement and the judiciary, the institutions that would be responsible for implementing such control.  相似文献   
84.
The Victorian Child Death Review Committee (VCDRC) in Australia is a multidisciplinary Ministerial Advisory Committee established to review the deaths of children either currently child protection clients or known to the statutory child protection system. The Committee provides advice about each child death as well as insights into what are the surrounding patterns and issues. Key to this role is examining the contribution of the service sectors to the protection of children and the routine practices that are in place to respond to children and vulnerability. This paper provides a snapshot of the cases referred to the VCDRC and the key messages for practice drawn from them. What emerges is that often the threshold for when statutory child protection services must be involved in child and family matters can be ambiguous and that agreement about intervention, the level and nature of need or risk, and when cumulative harm and neglect require statutory responses are not always shared between agencies. It is clear that the lack of common frameworks about what constitutes child protection intervention challenges services. It is recommended that there be and used agreed definitions and frameworks to ensure shared understandings and collaborative responses across the service and legal systems.  相似文献   
85.
丁飞鹏  陈建宝 《统计研究》2019,36(3):113-123
本文将最小二乘支持向量机(LSSVM) 和二次推断函数法(QIF) 相结合,为个体内具有相关结构的固定效应部分线性变系数面板模型提供了一种新的快速估计方法;在一定的正则条件下,论证了参数估计量的渐近正态性和非参数估计量的收敛速度;采用Monte Carlo模拟考察了估计方法在有限样本下的表现并将估计技术应用于现实数据分析。该方法不仅保证了估计的有效性和统计推断力,而且程序运行速度得到较大幅度提升。  相似文献   
86.
Non‐governmental organizations (NGOs) and the government of Nepal have made some effort to reduce poverty in Nepal by creating women's affiliation groups, some of which are micro‐credit organizations. Using capabilities as defined by Amartya Sen (Development as freedom, Oxford University Press, New Delhi, 2000), which includes employment opportunities, women's ownership in productive resources such as land and/or homes, educational opportunities, and women's participation in decision‐making in the family, this study evaluated the extent to which women's ethnic group or caste affiliation affected a woman's likelihood of being empowered by participation in these groups. We analyzed a sample of 8,973 women which was taken from the 2011 Nepal Demographic and Health Survey. Previous research has demonstrated that participation in gender‐based groups is correlated with higher economic status. This study adds to the literature on women's affiliation groups by investigating the impact of structural factors, such as caste and ethnicity, on women's self‐help group participation (women's groups and credit groups).  相似文献   
87.
88.
Recent research into school readiness has highlighted the importance of not only children's cognitive and socio‐emotional skills, but also the degree to which they have family support in the home. The current study examines the association between social success upon school entry and teacher‐ratings of school readiness as assessed by the Brief Early Skills and Support Index (BESSI), controlling for language ability. Importantly, social success was assessed using a “child's‐eye view” with peer‐reported assessments of both social preference and reciprocated friendships. A total of 244 children (131 boys, Mage = 61 months, SD = 4.78 months) in their first year of formal schooling participated. Child school readiness was found to be important for social preference, with the association being more marked for boys versus girls. Family support was the only independent predictor of children's reciprocated friendships. The use of the BESSI, with its broad scope compared to other measures of school readiness, highlights the importance of focusing both on a child's cognitive and socio‐emotional skills at school entry and their family support when exploring the association of school readiness to children's social success at the transition to formal schooling.  相似文献   
89.
In recent years, seamless phase I/II clinical trials have drawn much attention, as they consider both toxicity and efficacy endpoints in finding an optimal dose (OD). Engaging an appropriate number of patients in a trial is a challenging task. This paper attempts a dynamic stopping rule to save resources in phase I/II trials. That is, the stopping rule aims to save patients from unnecessary toxic or subtherapeutic doses. We allow a trial to stop early when widths of the confidence intervals for the dose-response parameters become narrower or when the sample size is equal to a predefined size, whichever comes first. The simulation study of dose-response scenarios in various settings demonstrates that the proposed stopping rule can engage an appropriate number of patients. Therefore, we suggest its use in clinical trials.  相似文献   
90.
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