Uncertainty and Sensitivity Analysis in Assessment of the Thyroid Cancer Risk Related to Chernobyl Fallout in Eastern France

The increase in the thyroid cancer incidence in France observed over the last 20 years has raised public concern about its association with the 1986 nuclear power plant accident at Chernobyl. At the request of French authorities, a first study sought to quantify the possible risk of thyroid cancer associated with the Chernobyl fallout in France. This study suffered from two limitations. The first involved the lack of knowledge of spontaneous thyroid cancer incidence rates (in the absence of exposure), which was especially necessary to take their trends into account for projections over time; the second was the failure to consider the uncertainties. The aim of this article is to enhance the initial thyroid cancer risk assessment for the period 1991-2007 in the area of France most exposed to the fallout (i.e., eastern France) and thereby mitigate these limitations. We consider the changes over time in the incidence of spontaneous thyroid cancer and conduct both uncertainty and sensitivity analyses. The number of spontaneous thyroid cancers was estimated from French cancer registries on the basis of two scenarios: one with a constant incidence, the other using the trend observed. Thyroid doses were estimated from all available data about contamination in France from Chernobyl fallout. Results from a 1995 pooled analysis published by Ron et al. were used to determine the dose-response relation. Depending on the scenario, the number of spontaneous thyroid cancer cases ranges from 894 (90% CI: 869-920) to 1,716 (90% CI: 1,691-1,741). The number of excess thyroid cancer cases predicted ranges from 5 (90% UI: 1-15) to 63 (90% UI: 12-180). All of the assumptions underlying the thyroid cancer risk assessment are discussed.     

基于模糊神经网络的企业人力资源风险评价

作者针对企业人力资源风险评价中的模糊性特点,将模糊逻辑与神经网络融合在一起,并应用模糊神经网络的评价方法,实现了对基于模糊神经网络的企业人力资源风险评价。该评价方法具有很强的学习能力,同时各个评价指标的权重是由网络通过学习自动生成的,因此更具客观性和准确性。     

Characterizing Environmental Harm: Developments in an Approach to Strategic Risk Assessment and Risk Management

Environmental policymakers and regulators are often in the position of having to prioritize their actions across a diverse range of environmental pressures to secure environmental protection and improvements. Information on environmental issues to inform this type of strategic analysis can be disparate; it may be too voluminous or even absent. Data on a range of issues are rarely presented in a common format that allows easy analysis and comparison. Nevertheless, judgments are required on the significance of various environmental pressures and on the inherent uncertainties to inform strategic assessments such as “state of the environment” reports. How can decisionmakers go about this type of strategic and comparative risk analysis? In an attempt to provide practical tools for the analysis of environmental risks at a strategic level, the Environment Agency of England and Wales has conducted a program of developmental research on strategic risk assessment since 1996. The tools developed under this program use the concept of “environmental harm” as a common metric, viewed from technical, social, and economic perspectives, to analyze impacts from a range of environmental pressures. Critical to an informed debate on the relative importance of these perspectives is an understanding and analysis of the various characteristics of harm (spatial and temporal extent, reversibility, latency, etc.) and of the social response to actual or potential environmental harm from a range of hazards. Recent developments in our approach, described herein, allow a presentation of the analysis in a structured fashion so as to better inform risk‐management decisions.     

律师风险代理制度探析

通过对国外律师风险代理制度的立法比较,论述了我国建立这一制度的实践价值和障碍,进而提出构建我国律师风险代理制度需要通过对其适用范围、基本开支的支付、律师请求留置权的赋予和律师收费评定制度等方面进行立法来加以规范。     

上市公司跨行业转型风险分析与评价

跨行业转型是企业发展过程中的战略选择,是企业保持持续发展或克服衰退重新获得竞争优势的重要手段,但跨行业转型在给企业带来发展机会的同时也带来巨大的风险。在转型决策时,识别风险因素,分析风险因素的作用过程,判断风险发生的可能性和发生时可能带来的损失,可以减少转型风险。本研究采取分步多层模糊综合评价方法反映转型风险的作用过程和风险因素间的不同层次,并用该方法对转型过程的风险进行了综合评价。     

助学贷款的风险防范机制研究

国家助学贷款推行难的主要原因是风险大,而助学贷款的外部经济性使得其风险防范与其他商业性贷款的风险防范有所不同。文章从分析国家助学贷款的各方当事人的收益成本及其行为出发,一方面判定助学贷款的风险应由哪些主体来分担;另一方面具体从短期和长期角度分别探讨助学贷款的风险防范机制。     

Improved minimax estimation of a normal precision matrix

Let S_{p × p} have a Wishart distribution with parameter matrix Σ and n degrees of freedom. We consider here the problem of estimating the precision matrix Σ^?1 under the loss functions L₁(σ) tr (σ) - log |σ| and L₂(σ) = tr (σ). James-Stein-type estimators have been derived for an arbitrary p. We also obtain an orthogonal invariant and a diagonal invariant minimax estimator under both loss functions. A Monte-Carlo simulation study indicates that the risk improvement of the orthogonal invariant estimators over the James-Stein type estimators, the Haff (1979) estimator, and the “testimator” given by Sinha and Ghosh (1987) is substantial.     

中国转型期的社会安全隐患与对策

中国转型期面临着严重的社会安全隐患,具体表现为多重风险共生、社会自身在保障安全方面具有脆弱性、社会应对风险的思维具有极化倾向。为了走向更加安全的社会,不仅要充分认识社会安全问题的重要性,而且要完善风险管理体系,实施多元化风险管理策略,正确认识国家的作用,高度重视风险教育,积极实践新型发展观。     

Domestic violence and child protection: exploring the role of perpetrator risk assessments

This article explores the issue of severity in relation to domestic violence and provides a number of reasons for the necessary engagement by workers with such a contentious issue. The specific role that the assessment of the risks posed by the perpetrator which has now developed in some police forces in the United Kingdom is examined, and its relevance to child welfare intervention discussed. A range of factors are identified that heighten the risks of increased violence. These include prior sexual assault; stalking and controlling behaviour; substance misuse and mental‐health problems; separation and child contact disputes; pregnancy; escalation including the use of weapons and psychological abuse; attempts and threats to kill; child abuse; isolation and barriers to help‐seeking. The ways in which perpetrator risk assessment can be used to inform the filtering of referrals to the statutory child care agency, enhance multi‐agency working, provide a structure for the assessment of the perpetrator, enhance partnership‐working with survivors (usually women) and inform the protection strategies for workers are explored.     

Assessing Cancer Risks from Short-Term Exposures in Children

For the vast majority of chemicals that have cancer potency estimates on IRIS, the underlying database is deficient with respect to early-life exposures. This data gap has prevented derivation of cancer potency factors that are relevant to this time period, and so assessments may not fully address children's risks. This article provides a review of juvenile animal bioassay data in comparison to adult animal data for a broad array of carcinogens. This comparison indicates that short-term exposures in early life are likely to yield a greater tumor response than short-term exposures in adults, but similar tumor response when compared to long-term exposures in adults. This evidence is brought into a risk assessment context by proposing an approach that: (1) does not prorate children's exposures over the entire life span or mix them with exposures that occur at other ages; (2) applies the cancer slope factor from adult animal or human epidemiology studies to the children's exposure dose to calculate the cancer risk associated with the early-life period; and (3) adds the cancer risk for young children to that for older children/adults to yield a total lifetime cancer risk. The proposed approach allows for the unique exposure and pharmacokinetic factors associated with young children to be fully weighted in the cancer risk assessment. It is very similar to the approach currently used by U.S. EPA for vinyl chloride. The current analysis finds that the database of early life and adult cancer bioassays supports extension of this approach from vinyl chloride to other carcinogens of diverse mode of action. This approach should be enhanced by early-life data specific to the particular carcinogen under analysis whenever possible.