Dose-Response and Risk Assessment of Airborne Hexavalent Chromium and Lung Cancer Mortality

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).     

Child sexual abuse and psychological impairment in victims: results of an online study initiated by victims

Sexual abuse of children has been a topic of scientific investigation for the past few decades. Research in this area, however, is rarely initiated, conceptualized, and conducted by victims themselves. Apart from possibly having painted a one-sided picture of sexual abuse, this presumed dominance of nonvictims might also have marginalized victims in a research area central to their lives. This study was conducted by a victims interest group as an effort to meet the need to add victims' perspectives to our current understanding of this topic. The online survey focused on investigating victims' psychosocial impairment, which was found to be extensive. Results indicated that an intact social support system facilitates better health, especially when offered early on.     

Peak Exposures in Epidemiologic Studies and Cancer Risks: Considerations for Regulatory Risk Assessment

We review approaches for characterizing “peak” exposures in epidemiologic studies and methods for incorporating peak exposure metrics in dose–response assessments that contribute to risk assessment. The focus was on potential etiologic relations between environmental chemical exposures and cancer risks. We searched the epidemiologic literature on environmental chemicals classified as carcinogens in which cancer risks were described in relation to “peak” exposures. These articles were evaluated to identify some of the challenges associated with defining and describing cancer risks in relation to peak exposures. We found that definitions of peak exposure varied considerably across studies. Of nine chemical agents included in our review of peak exposure, six had epidemiologic data used by the U.S. Environmental Protection Agency (US EPA) in dose–response assessments to derive inhalation unit risk values. These were benzene, formaldehyde, styrene, trichloroethylene, acrylonitrile, and ethylene oxide. All derived unit risks relied on cumulative exposure for dose–response estimation and none, to our knowledge, considered peak exposure metrics. This is not surprising, given the historical linear no‐threshold default model (generally based on cumulative exposure) used in regulatory risk assessments. With newly proposed US EPA rule language, fuller consideration of alternative exposure and dose–response metrics will be supported. “Peak” exposure has not been consistently defined and rarely has been evaluated in epidemiologic studies of cancer risks. We recommend developing uniform definitions of “peak” exposure to facilitate fuller evaluation of dose response for environmental chemicals and cancer risks, especially where mechanistic understanding indicates that the dose response is unlikely linear and that short‐term high‐intensity exposures increase risk.     

“达尔文难题”的解释方法及其博弈论模型研究

文章在科学哲学的视野下分析了解释达尔文难题的几种路径:群体选择理论、亲缘选择理论、互惠理论、副产品理论等。首先分析了这些途径各自的论域、理论自洽性和局限性等问题。进而提出在社会生物学范式下利他问题的两种研究的方法论:第一,对所有动物共有的利他行为进行分类,并提出了新的分类标准;第二,对人类特有的利他行为构建新的研究纲领进行研究。随后在新的研究纲领下构建了人类纯粹利他行为的博弈论模型。并提出利他问题的最终解决需要综合自然主义方法与非自然主义方法才能实现。     

Child Sexual Abuse and Psychological Impairment in Victims: Results of an Online Study Initiated by Victims

Sexual abuse of children has been a topic of scientific investigation for the past few decades. Research in this area, however, is rarely initiated, conceptualized, and conducted by victims themselves. Apart from possibly having painted a one-sided picture of sexual abuse, this presumed dominance of nonvictims might also have marginalized victims in a research area central to their lives. This study was conducted by a victims interest group as an effort to meet the need to add victims' perspectives to our current understanding of this topic. The online survey focused on investigating victims' psychosocial impairment, which was found to be extensive. Results indicated that an intact social support system facilitates better health, especially when offered early on.     

量子密码及其“不可破译性”

在21世纪人类跨入信息时代之际,如何能够实现保密通信的不可破译性是现代通信技术面临的重要问题,也是哲学工作者需要思考的重要问题.量子密码术在保证信息的不可破译性方面已经取得重要进展.通过对非量子密码术和量子密码术两个阶段分别以科学的和哲学的解析,文章认为,古代密码术具有弱不可破译性,发展到经典密码术阶段,密码术在理论和实践上呈现强不可破译性,而量子密码术则显示出不可破译性,逐渐趋向"绝对不可破译性".     

Political Opposition in Russia: Is it Becoming Extinct

This article uses Russian experience to examine several issues concerning the relationship of electoral procedures, democratization, and liberalization. The author's interpretation of certain aspects of the political process in contemporary Russia does not coincide with the opinions of other researchers, including some published in our journal. L. Diamond raised a similar set of predominantly theoretical issues in "Is the 'Third Wave' of Democratization Over?" [Polis, 1999, no. 1].     

实施新型农村合作医疗制度的困境与对策——以四川省宜宾市珙县洛亥镇试点为例

新型农村合作医疗制度是新时期建设社会主义新农村的重要举措。宜宾市在实施农村新型合作医疗制度的过程中存在着宣传不到位、方案和体制不健全、网络不完善等问题。要把这项民心工程落到实处,政府部门要广泛动员,总体规划,优化资源,加强对资金的管理力度,完善管理体制。     

近年来我国科技文化研究综述

自2004年全国“科技文化与社会现代化”学术研讨会在武汉理工大学召开至今,学术界在科技文化研究方面取得了丰硕成果。文章从科技文化的内涵、科技文化软实力与文化强国战略、科技文化的当代反思、科技文化的生境机制等方面,对其进行了择要论述,在此基础上,对科技文化研究进行展望。     

当代中国社会利益分化的和谐价值

改革开放以来,我国社会利益分化虽然不可避免对社会和谐发展产生了一些消极影响,但是从总体上看,这种分化对社会和谐发展是有利的。主要体现在：利益分化促进经济发展,为社会和谐奠定坚实基础;利益分化打破原有利益格局,使我国社会由传统向现代转变;利益分化推动阶级阶层的合理化和阶级阶层内部整合;利益分化促进社会民主和社会规范建设以及有利于及早发现矛盾并把其消灭于萌芽之中,促进社会和谐。