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71.
72.
Children may be more susceptible to toxicity from some environmental chemicals than adults. This susceptibility may occur during narrow age periods (windows), which can last from days to years depending on the toxicant. Breathing rates specific to narrow age periods are useful to assess inhalation dose during suspected windows of susceptibility. Because existing breathing rates used in risk assessment are typically for broad age ranges or are based on data not representative of the population, we derived daily breathing rates for narrow age ranges of children designed to be more representative of the current U.S. children's population. These rates were derived using the metabolic conversion method of Layton (1993) and energy intake data adjusted to represent the U.S. population from a relatively recent dietary survey (CSFII 1994–1996, 1998). We calculated conversion factors more specific to children than those previously used. Both nonnormalized (L/day) and normalized (L/kg-day) breathing rates were derived and found comparable to rates derived using energy estimates that are accurate for the individuals sampled but not representative of the population. Estimates of breathing rate variability within a population can be used with stochastic techniques to characterize the range of risk in the population from inhalation exposures. For each age and age-gender group, we present the mean, standard error of the mean, percentiles (50th, 90th, and 95th), geometric mean, standard deviation, 95th percentile, and best-fit parametric models of the breathing rate distributions. The standard errors characterize uncertainty in the parameter estimate, while the percentiles describe the combined interindividual and intra-individual variability of the sampled population. These breathing rates can be used for risk assessment of subchronic and chronic inhalation exposures of narrow age groups of children.  相似文献   
73.
这篇论文旨在解决英语词汇教学方面的问题。在分析学生词汇习得的基础上和对教学法的回顾和讨论的基础上,论文得出了一些可考的观点。  相似文献   
74.
王志勇 《兰州学刊》2008,2(3):36-39
文章有两大基本特点:对波普诘难历史决定论的质疑是从政治学这个独特视角进行的;对波普诘难历史决定论的质疑主要是针对哲学界较少关注的几个观点。这些观点包括波普过分推崇讧伪的方法,贬低和轻视证实方法的观点;波普认为整体主义不能建设一个适合于人们生活的新社会,只能建设一个使人适合于他的新社会的观点;波普认为渐进工程工程师在改革范围内可以不抱成见提出自己问题的观点。对于这些观点,文章借用罗尔斯、阿尔蒙德、伊斯顿、科恩、熊彼得、林尚立等的观点和理论对其进行了深入的剖析。  相似文献   
75.
76.
随着经济的发展 ,法制的完善以及审判方式改革的深化 ,法院调解这一纠纷解决方式以其独特的优点 ,在司法实践中 ,越来越显示其重要性。时代赋予法院调解新的价值的同时 ,也使其原有的法律规定弊端凸现。本文拟从法院调解三原则的地位分析中寻找促进和规范法院调解的途径 ,并运用新证据规则加以落实。  相似文献   
77.
Family development and prospect theory were used as a framework to predict variability in individuals' subjective financial risk tolerance within distinct family structures. Gender, age, and income were expected to interact with the main effects of family structure (marital status and children). Theory-generated hypotheses were examined in Study 1 (data from university housing respondents, n = 76) and Study 2 (the 1998 Survey of Consumer Finances, n = 4,305). One family structure main effect (child presence) was significant for investment risk tolerance in both studies. Family structure interactions (marital status × age and child × income) were significant for employment risk (Study 1), and child × age was significant for investment risk in Study 2.  相似文献   
78.
For a wide variety of applications, experiments are based on units ordered over time or space. Models for these experiments generally may include one or more of: correlations, systematic trends, carryover effects and interference effects. Since the standard optimal block designs may not be efficient in these situations, orthogonal arrays of type I and type II, which were introduced in 1961 by C.R. Rao [Combinatorial arrangements analogous to orthogonal arrays, Sankhya A 23 (1961) 283–286], have been recently used to construct optimal and efficient designs for many of these experiments. Results in this area are unified and the salient features are outlined.  相似文献   
79.
探究公立高校学生管理的法治化,推进高校依法治校,促进高校和谐管理正日益成为高校构建和谐校园的重要方面。从传统高校学生管理存在的问题入手,提出了新时期高校学生的管理应当以构建和谐校园为目标,正确认识高校与学生的法律关系,把握高校学生管理的法治化原则,探究高校学生管理法治化道路。  相似文献   
80.
The dual concepts of 'consent' and 'informed consent' continue to have three evolutions. The primary evolution of consent in the patient–physician relationship began in Great Britain in 1767 in the British case, Slater v. Baker and Stapleton , in the judge-made law of consent. The term 'informed consent' within the patient–physician relationship entered the judicial lexicon in the 1957 California appellate case, Salgo v. Leland Stanford Junior University . In its second evolution within research on humans following the Nuremberg trials that included experimental atrocities on humans, there is a key focus on clarifying the purpose of research and specifying the reasons for the need for an even more extensive risk disclosure to individuals considering volunteering for study participation. This second evolution continues with the further refinement of the Declaration of Helsinki and, within the USA, a focus on the Belmont Report . In its third evolution in research in the social science, there has been a recognition of problems with informed consent to questionnaire research. When questionnaires involve patients with moderate or severe posttraumatic stress disorder or abused individuals, there needs to be intense consideration focused on how to best protect the participants with these conditions during the questionnaire study.  相似文献   
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