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21.
Biological threat characterization (BTC) involves laboratory research conducted for the purpose of biological defense. BTC research is important for improving biological risk assessment and informing resource prioritization. However, there are also risks involved in BTC work, including potential for escape from the laboratory or the misuse of research results. Using a modified Delphi study to gather opinions from U.S. experts in biosecurity and biodefense, this analysis explores what principles and safeguards can maximize the benefits of BTC research and ensure that it is conducted safely and securely. Delphi participants were asked to give their opinions about the need for BTC research by the U.S. government (USG); risks of conducting this research; rules or guidelines that should be in place to ensure that the work is safe and accurate; components of an effective review and prioritization process; rules for when characterization of a pathogen can be discontinued; and recommendations about who in the USG should be responsible for BTC prioritization decisions. The findings from this research reinforce the need for BTC research at the federal level as well as a need for continued review and oversight of this research to maximize its effectiveness and reduce the risks involved. It also demonstrates the need for further discussion of what would constitute a “red line” for biothreat characterization research—research that should not be performed for safety, ethical, or practical reasons—and guidelines for when there is sufficient research in a given topic area so that the research can be considered completed.  相似文献   
22.
This article develops a quantitative all-hazards framework for critical asset and portfolio risk analysis (CAPRA) that considers both natural and human-caused hazards. Following a discussion on the nature of security threats, the need for actionable risk assessments, and the distinction between asset and portfolio-level analysis, a general formula for all-hazards risk analysis is obtained that resembles the traditional model based on the notional product of consequence, vulnerability, and threat, though with clear meanings assigned to each parameter. Furthermore, a simple portfolio consequence model is presented that yields first-order estimates of interdependency effects following a successful attack on an asset. Moreover, depending on the needs of the decisions being made and available analytical resources, values for the parameters in this model can be obtained at a high level or through detailed systems analysis. Several illustrative examples of the CAPRA methodology are provided.  相似文献   
23.
本文研究了同时考虑竞争者进入威胁和消费者行为的易逝品的动态定价机制.依据策略性和忠诚性两个维度,将市场中的消费者分为策略型忠诚者、策略型转换者、短视型忠诚者和短视型转换者四种类型.建立了在位企业、竞争企业与策略消费者间的两阶段动态博弈模型,通过均衡求解与分析,探讨了在位企业和竞争企业的最优价格机制以及消费者行为对企业定价行为和均衡收益的影响,深入分析了竞争者的进入行为对在位企业定价和收益的影响,以及消费者策略行为和转换行为与竞争者进入行为间的交互作用机制.研究表明:在位企业可以依据策略消费者的比例,采取智能的动态定价机制,实行或放弃对策略消费者的跨期价格歧视,最大化自身收益;消费者策略行为会降低在位企业的绩效却能够提高竞争者的绩效;竞争者的进入并非总是对在位企业不利,在一定条件下,竞争者的进入有利于提高在位企业的绩效;在位企业通过多种方式培养自己的忠实顾客,不仅能够应对竞争者的进入威胁而且能够缓解消费者策略行为的负面影响.  相似文献   
24.
在美国,研究已经多次证明关于智力的否定性固有观念会妨碍受这些固有观念影响的个体的成绩表现。在中国,认为女性在数学上弱于男性的观念已经持续了很长时间。本文通过一项程度颇深的数学和英语测试,对中国大学生进行了关于传统固有观念暗示理论的研究。在数学测试中,研究的假设是:同美国测试者的表现相似,受“性别数学”固有差异观念影响的女性测试者的成绩要比不受固有观念影响的人差;而在英语测试中,研究则假设受“性别语言”固有差异观念影响的男性会比不受此种观念影响的人得分低。然而测试的结果并没有证实这两个假设。研究结果对当今中国现存的社会和教育因素进行了讨论。  相似文献   
25.
通过分析淮安正在加速推进工业化、走低碳导向型工业化的道路情况,明晰淮安发展低碳工业既有产业结构调整升级空间大等优势,也有产业结构层次低等劣势;有政策鼓励等机会,也有体制机制等方面的威胁。  相似文献   
26.
Postdivorce identity challenges can be experienced differently in societies that underline the lack of normalcy of divorce. Therefore, this study was conducted to explore Iranian divorced women’s perceptions of their identities. A qualitative content analysis method was applied. Participants included 18 divorced women recruited based on purposive sampling. Data were gathered using unstructured interviews, and analyzed via content analysis method. Three categories—stigmatization, separation shock, and remarriage paradox—were extracted, and the main theme was identity threat. Findings illustrate that Iranian divorced women can be considered at risk, and hence, understanding their views is vital for developing context-specific preventive and intervention programs.  相似文献   
27.
Quantification of childhood adversity has typically involved a cumulative risk approach in which total number of discrete adversities serves as an index of overall risk. However, this approach fails to account for the growing evidence of differential outcomes following exposure to childhood adversities. An alternative approach adopts a dimensional perspective, with growing evidence for distinct developmental impacts associated with exposure to threat (violence/abuse) and deprivation (neglect). This study developed a framework for the classification of these dimensions through a thematic analysis of health practitioners' views and accounts of different forms of childhood adversity. Ten health practitioners experienced in working with children with challenging behaviours and neurodevelopmental disorders participated in semi-structured interviews regarding definitions and examples of six categories of adversity: physical/emotional/sexual abuse, physical/emotional neglect, and domestic and family violence. The qualitative analysis identified 23 themes across the six categories of adversity, along with two overarching themes regarding ambiguity of classifying exposures and non-specific outcomes of exposures. Themes were integrated to provide a framework and checklist for classifying indicators of exposure to threat and deprivation. The findings offer a framework and checklist for the assessment of threat and deprivation that will allow for further testing of the dimensional risk model.  相似文献   
28.
Existing literature on numeracy suggests that people are likely to perceive outgroups as larger if the group is perceived as threatening. However, some studies also suggest that numeracy is a function of wishful thinking or even a lack of political knowledge. We engage the literature on numeracy of the gay and lesbian population by employing data from 1977 and 2013 surveys of American adults. We examine the factors that are associated with estimating the gay population. Next we explore how innumeracy may shape attitudes about homosexuality and gay rights. Our findings suggest that estimates of the gay population are partly a function of knowledge, and perhaps wishful thinking, but not threat. However, our analysis also reveals that higher estimates of the gay population are associated with less support for gay civil rights in the current era and were not a factor in the past.  相似文献   
29.
Illegitimate tasks represent a task-level stressor derived from role and justice theories within the framework of “Stress-as–Offense-to-Self” (SOS; Semmer, Jacobshagen, Meier, & Elfering, 2007). Tasks are illegitimate if they violate norms about what an employee can properly be expected to do, because they are perceived as unnecessary or unreasonable; they imply a threat to one's professional identity. We report three studies testing associations between illegitimate tasks and well-being/strain. In two cross-sectional studies, illegitimate tasks predicted low self-esteem, feelings of resentment towards one's organization and burnout, controlling for role conflict, distributive injustice and social stressors in Study 1, and for distributive and procedural/interactional justice in Study 2. In Study 3, illegitimate tasks predicted two strain variables (feelings of resentment towards one's organization and irritability) over a period of two months, controlling for initial values of strain. Results confirm the unique contribution of illegitimate tasks to well-being and strain, beyond the effects of other predictors. Moreover, Study 3 demonstrated that illegitimate tasks predicted strain, rather than being predicted by it. We therefore conclude that illegitimate tasks represent an aspect of job design that deserves more attention, both in research and in decisions about task assignments.  相似文献   
30.
An essential factor toward ensuring the security of individuals and critical infrastructures is the timely detection of potentially threatening situations. To this end, especially in the law enforcement context, the availability of effective and efficient threat assessment mechanisms for identifying and eventually preventing crime- and terrorism-related threatening situations is of utmost importance. Toward this direction, this work proposes a hidden Markov model-based threat assessment framework for effectively and efficiently assessing threats in specific situations, such as public events. Specifically, a probabilistic approach is adopted to estimate the threat level of a situation at each point in time. The proposed approach also permits the reflection of the dynamic evolution of a threat over time by considering that the estimation of the threat level at a given time is affected by past observations. This estimation of the dynamic evolution of the threat is very useful, since it can support the decisions by security personnel regarding the taking of precautionary measures in case the threat level seems to adopt an upward trajectory, even before it reaches the highest level. In addition, its probabilistic basis allows for taking into account noisy data. The applicability of the proposed framework is showcased in a use case that focuses on the identification of potential threats in public events on the basis of evidence obtained from the automatic visual analysis of the footage of surveillance cameras.  相似文献   
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