Potential exposures and risks from beryllium-containing products.

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.     

新型蓄光性长余辉荧光陶瓷的研制

研究了基础釉的成分、蓄光粉的加入量、釉层厚度和烧成温度制度等因素对蓄光陶瓷发光性能的影响以及各种制品最佳工艺技术路线的确定.     

Costs and Rewards of Children: The Effects of Becoming a Parent on Adults' Lives

How do new parents differ from their childless counterparts in social and psychological resources, daily strains, and psychological well‐being? Using a nationally representative panel of 1,933 adults who were childless at the first interview, we compare 6 indicators of adults' lives for those who became parents and those remaining childless several years later, controlling for earlier states. Becoming a parent is both detrimental and rewarding. With the exception of social integration, which is greater for all groups of new parents compared with their childless counterparts, the effects of parental status on adults' lives vary markedly by gender and marital status. Unmarried parents report lower self‐efficacy and higher depression than their childless counterparts. Married mothers' lives are marked by more housework and more marital conflict but less depression than their childless counterparts. Parental status has little influence on the lives of married men.     

Valuation of childhood risk reduction: the importance of age, risk preferences, and perspective.

This article explores two problems analysts face in determining how to estimate values for children's health and safety risk reductions. The first addresses the question: Do willingness‐to‐pay estimates for health risk changes differ across children and adults and, if so, how? To answer this question, the article first examines the potential effects of age and risk preferences on willingness to pay. A summary of the literature reporting empirical evidence of differences between willingness to pay for adult health and safety risk reductions and willingness to pay for health and safety risk reductions in children is also provided. The second dimension of the problem is a more fundamental issue: Whose perspective is relevant when valuing children's health effects—society's, children's, adults‐as‐children, or parents'? Each perspective is considered, followed ultimately by the conclusion that adopting a parental perspective through an intrahousehold allocation model seems closest to meeting the needs of the estimation problem at hand. A policy example in which the choice of perspective affects the outcome of a regulatory benefit‐cost analysis rounds out the article and emphasizes the importance of perspective.     

加拿大高等教育的特色与启示

加拿大高等教育的特点主要体现在管理体制和教育教学两个方面,包括:联邦政府不设教育部;分为大学和学院两个系统;多样化的联合办学模式;完全学分制;宽口径厚基础的课程体系;启发式的教学模式,等等.加拿大高等教育给予我们的启示有:树立以人为本的办学理念,实施完全学分制;理性思考学校定位,开展多渠道合作办学;整体优化培养方案,实施启发式教学方法;建立科学的高校内部评价体系,等等.     

教育服务理论与学校管理理念转变的思考

以教育服务理论为依据,从经济学角度,阐述了教育服务是教育产品,学校是教育服务产品的生产者和供给者,学生是教育服务产品的消费者和需求者。指出学校应以经营的理念管理学校,以消费者(生源)为本,充分发挥学校教育服务的优势,向市场和消费者提供品牌和特色的优质的教育服务,以吸引更多的消费者。     

中国传统修辞学的继承

20世纪初诞生的中国现代修辞学,较多地受西方修辞理论的影响。要提高修辞学的品位与社会功用,就必须继承中国修辞学传统,建立具有民族特色的修辞学体系,重视中国古代修辞学学术传统,重新考虑修辞学的内容与体系、方法与方法论等问题。     

建筑业项目经理的压力状况调查

建筑企业自身在市场中所面临的竞争压力是不可避免的,而企业中内在的缺陷与不足也会为企业带来一定的压力.过多压力不仅有害于员工的身心健康,而且会给企业带来巨额的经济损失,项目经理是建筑企业项目得以实现并获得长远发展的关键角色之一.此项研究在调查问卷的基础之上,调查了我国建筑业项目经理压力水平,并从项目经理的职业特点出发,分析了我国项目经理压力水平偏高的原因,为我国建筑业实行压力管理迈出了重要的一步.     

庄严而残忍的悲歌--重读老鬼的《血色黄昏》

本文从《血色黄昏》反映生活的真实性、作者塑造人物形象的典型性以及独特的表现风格三个方面,对小说作了评述。     

南京市中学生自尊心调查与分析

对南京市中学生的235份有效调查问卷表明,目前中学生对自尊状况的体验多数趋于“一般化”,但都较普遍地存在对自尊的焦虑感、敏感性、渴求性、盲目性、积极性并存的特点也很明显。中学生自尊与自尊心理的发生机制源自于教师与伙伴的外部评价,又源自于自身生理状况、能力。气质与童年经历的影响,中学生自尊与自卑心理的平衡机制存在于对理想自我标准的坚持、修正或放弃选择。学校教育培养中学生自尊心的有效切入点是:提高知识水平、培养羞耻感、锻炼意志力、培养尊重他人的品质。