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1.
社会主义市场经济条件下 ,作为党、政府和人民的耳目喉舌的新闻媒体 ,仍然必须牢牢坚持新闻指导性原则 ,这是由我国无产阶级新闻事业的基本性质所决定的 ,是新形势下广大受众政治、经济生活的迫切需要。为了不断增强指导效果 ,新闻媒体当前主要应从以下几方面改进指导方法 :改变指挥命令的做法 ,在服务中增强指导性 ;力戒图解政策 ,通过深入实际、反映实际增强指导性 ;防止片面性、简单化 ,以客观、全面、辩证的方法增强指导性  相似文献   
2.
Summary. This study investigates whether there was evidence of increasing risk of still-birth with increasing paternal exposure to ionizing radiation received during employment at the Sellafield nuclear installation before the child was conceived. A significant positive association is found between the total paternal preconceptional exposure to external ionizing radiation and the risk of still-birth (after adjustment for year of birth, social class, birth order and paternal age, odds ratio at 100 mSv 1.24 (95% confidence interval 1.04–1.45)). A summary of the principal scientific findings of this study has been published in the Lancet . This paper describes in detail the statistical methods that were used in the investigation and presents the results in full.  相似文献   
3.
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   
4.
Bayesian analysis of discrete time warranty data   总被引:1,自引:0,他引:1  
Summary.  The analysis of warranty claim data, and their use for prediction, has been a topic of active research in recent years. Field data comprising numbers of units returned under guarantee are examined, covering both situations in which the ages of the failed units are known and in which they are not. The latter case poses particular computational problems for likelihood-based methods because of the large number of feasible failure patterns that must be included as contributions to the likelihood function. For prediction of future warranty exposure, which is of central concern to the manufacturer, the Bayesian approach is adopted. For this, Markov chain Monte Carlo methodology is developed.  相似文献   
5.
高校全程就业指导模式构建研究   总被引:16,自引:0,他引:16  
目前高校就业指导现状已不适应高等教育和社会发展的需要。本文以心理测量指导、职业生涯设计指导、学业指导、择业指导、创业指导、升学指导六大指导为主线建构全程化的就业指导模式,全程就业指导就是从大学一年级开始,根据职业指导理论和大学生发展阶段,对大学生分年级、分阶段,结合学生共性与个性,提供全程化就业指导,以实现双向选择、人职匹配和职业目标。  相似文献   
6.
政府部门与企业同属社会公共组织,两者的绩效评估具有可比性。政府绩效评估和企业绩效评估可以相互借鉴:政府绩效评估可以借鉴企业绩效评估的评估技术、价值导向、评估方法;政府绩效评估可以引导企业绩效评估关注企业的社会责任。  相似文献   
7.
Beryllium is the strongest of the lightweight metals. Used primarily in military applications prior to the end of the Cold War, beryllium is finding new applications in many commercial products, including computers, telecommunication equipment, and consumer and automotive electronics. The use of beryllium in nondefense consumer applications is of concern because beryllium is toxic. Inhalation of beryllium dust or vapor causes a chronic lung disease in some individuals at concentrations as low as 0.01 microg/m3 in air. As beryllium enters wider commerce, it is prudent to ask what risks this might present to the general public and to workers downstream of the beryllium materials industry. We address this question by evaluating the potential for beryllium exposure from the manufacturing, use, recycle, and disposal of beryllium-containing products. Combining a market study with a qualitative exposure analysis, we determine which beryllium applications and life cycle phases have the largest exposure potential. Our analysis suggests that use and maintenance of the most common types of beryllium-containing products do not result in any obvious exposures of concern, and that maintenance activities result in greater exposures than product use. Product disposal has potential to present significant individual risks, but uncertainties concerning current and future routes of product disposal make it difficult to be definitive. Overall, additional exposure and dose-response data are needed to evaluate both the health significance of many exposure scenarios, and the adequacy of existing regulations to protect workers and the public. Although public exposures to beryllium and public awareness and concern regarding beryllium risks are currently low, beryllium risks have psychometric qualities that may lead to rapidly heightened public concern.  相似文献   
8.
This study evaluates the dose-response relationship for inhalation exposure to hexavalent chromium [Cr(VI)] and lung cancer mortality for workers of a chromate production facility, and provides estimates of the carcinogenic potency. The data were analyzed using relative risk and additive risk dose-response models implemented with both Poisson and Cox regression. Potential confounding by birth cohort and smoking prevalence were also assessed. Lifetime cumulative exposure and highest monthly exposure were the dose metrics evaluated. The estimated lifetime additional risk of lung cancer mortality associated with 45 years of occupational exposure to 1 microg/m3 Cr(VI) (occupational exposure unit risk) was 0.00205 (90%CI: 0.00134, 0.00291) for the relative risk model and 0.00216 (90%CI: 0.00143, 0.00302) for the additive risk model assuming a linear dose response for cumulative exposure with a five-year lag. Extrapolating these findings to a continuous (e.g., environmental) exposure scenario yielded an environmental unit risk of 0.00978 (90%CI: 0.00640, 0.0138) for the relative risk model [e.g., a cancer slope factor of 34 (mg/kg-day)-1] and 0.0125 (90%CI: 0.00833, 0.0175) for the additive risk model. The relative risk model is preferred because it is more consistent with the expected trend for lung cancer risk with age. Based on statistical tests for exposure-related trend, there was no statistically significant increased lung cancer risk below lifetime cumulative occupational exposures of 1.0 mg-yr/m3, and no excess risk for workers whose highest average monthly exposure did not exceed the current Permissible Exposure Limit (52 microg/m3). It is acknowledged that this study had limited power to detect increases at these low exposure levels. These cancer potency estimates are comparable to those developed by U.S. regulatory agencies and should be useful for assessing the potential cancer hazard associated with inhaled Cr(VI).  相似文献   
9.
汉外文化差异会直接影响对外汉语教学效果,因此语言教学必须与文化教学紧密结合,不可分割,否则会影响交际,甚至引起文化冲突。本文以汉俄两种语言对比为例,论述了汉外文化差异及其将文化导入语言教学的方法。  相似文献   
10.
良好的社会心态既是构建社会主义和谐社会的一种内在要求,也是和谐社会建设的重要心理资源。在社会转型时期,由收入差距扩大引起的不公平感和社会生活中的焦虑感,使低收入群体遭受到物质和精神上的双层困扰,并产生政治上的冷漠心态和信仰上的迷茫,为此,需要在社会意识领域做好教育疏导工作,更要在社会存在领域做好良好社会心态的强本固基工作。  相似文献   
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