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71.
We built three simulation models that can assist rail transit planners and operators to evaluate high and low probability rail‐centered hazard events that could lead to serious consequences for rail‐centered networks and their surrounding regions. Our key objective is to provide these models to users who, through planning with these models, can prevent events or more effectively react to them. The first of the three models is an industrial systems simulation tool that closely replicates rail passenger traffic flows between New York Penn Station and Trenton, New Jersey. Second, we built and used a line source plume model to trace chemical plumes released by a slow‐moving freight train that could impact rail passengers, as well as people in surrounding areas. Third, we crafted an economic simulation model that estimates the regional economic consequences of a variety of rail‐related hazard events through the year 2020. Each model can work independently of the others. However, used together they help provide a coherent story about what could happen and set the stage for planning that should make rail‐centered transport systems more resistant and resilient to hazard events. We highlight the limitations and opportunities presented by using these models individually or in sequence.  相似文献   
72.
ABSTRACT

Objectives: To identify salient behavioral determinants related to STI testing among college students by testing a model based on the integrative model of behavioral (IMBP) prediction. Participants: 265 undergraduate students from a large university in the Southeastern US. Methods:Formative and survey research to test an IMBP-based model that explores the relationships between determinants and STI testing intention and behavior. Results: of path analyses supported a model in which attitudinal beliefs predicted intention and intention predicted behavior. Normative beliefs and behavioral control beliefs were not significant in the model; however, select individual normative and control beliefs were significantly correlated with intention and behavior. Conclusions: Attitudinal beliefs are the strongest predictor of STI testing intention and behavior. Future efforts to increase STI testing rates should identify and target salient attitudinal beliefs.  相似文献   
73.
Disturbances in affect have been linked to problem behavior in adolescence and future psychopathology, but little is known about how such disturbances manifest themselves in everyday contexts. This study investigated daily mood in Dutch 7th graders, aged 11–14. Cluster analysis of problem measures distinguished high-risk (n=25) and low-risk (n=106) subgroups. Participants completed experience-sampling reports of mood, social context, and location nine times daily for 5 days. Multilevel regression analyses of four mood measures confirmed higher anxiety and depressed mood in the high-risk group. Moods varied by location and social context, with significant differences between groups in two specific social contexts. First, when with family, low-risk adolescents felt less depressed than when alone, whereas high-risk adolescents felt more depressed. Second, high-risk adolescents showed more pronounced anxiety in social situations outside the network of family and friends. These findings point to everyday social contexts in which young adolescents with emotional and behavioral problems appear to be particularly vulnerable.  相似文献   
74.
Federal and other regulatory agencies often use or claim to use a weight of evidence (WoE) approach in chemical evaluation. Their approaches to the use of WoE, however, differ significantly, rely heavily on subjective professional judgment, and merit improvement. We review uses of WoE approaches in key articles in the peer‐reviewed scientific literature, and find significant variations. We find that a hypothesis‐based WoE approach, developed by Lorenz Rhomberg et al., can provide a stronger scientific basis for chemical assessment while improving transparency and preserving the appropriate scope of professional judgment. Their approach, while still evolving, relies on the explicit specification of the hypothesized basis for using the information at hand to infer the ability of an agent to cause human health impacts or, more broadly, affect other endpoints of concern. We describe and endorse such a hypothesis‐based WoE approach to chemical evaluation.  相似文献   
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76.
The primary purpose of this study was to contrast the life satisfaction of midlife empty-nest and childless individuals. Seventy-two men and women reported on their satisfaction with 11 areas of life as well as with regard to children. Empty-nest individuals were more satisfied than childless persons with regard to their decisions regarding children; however, the childless individuals were not unhappy with their decisions. Empty-nest individuals were also more positive than childless individuals about contact with children. There were no differences between the two groups with regard to areas of life satisfaction not related to children; nor were there significant gender differences in life satisfaction. The results were discussed in relation to both theory and data concerning midlife satisfaction and adjustment.SMS AssociatesThe research was completed by James E. Bell in partial fulfillment of the requirement for the masters of counseling degree at Arizona State University.  相似文献   
77.
为什么说一封推荐信不能让中国学生在国外得到承认?“你的信能改变我的命运。”这是一个中国学生对我说的话,她毕生的梦想就是去美国学习。我在2007年9月遇见了她,恰好是我来清华大学新闻与传播学院当客座教授的那一周。这个学生来参加我的午餐演讲会,我们彼此交谈了一些开心的事情。她随后用电子邮件给我发来一封问候信,  相似文献   
78.
Children of Adolescent Mothers: Cognitive and Behavioral Status at Age Six   总被引:1,自引:0,他引:1  
The cognitive and behavioral status at age six years of 185 children of adolescent mothers (60.5% boys) were assessed using the mother (CBCL) and teacher (TRF) report forms of the Child Behavior Checklist and the Bracken Basic Concepts Scale. There was evidence for impairment in all areas of functioning. More than half of the sample exceeded the borderline clinical cutoff (T = 60) on either the CBCL or TRF Total Problem score, and nearly half the sample had Bracken scores that were more than 1 SD below the normative mean. Only 26.9% of the children were in the normal range on all three measures. These results are discussed in terms of implications for social work practice with children and adolescent mother families.  相似文献   
79.
80.
 In this paper we characterize strategy-proof voting schemes on Euclidean spaces. A voting scheme is strategy-proof whenever it is optimal for every agent to report his best alternative. Here the individual preferences underlying these best choices are separable and quadratic. It turns out that a voting scheme is strategy-proof if and only if (α) its range is a closed Cartesian subset of Euclidean space, (β) the outcomes are at a minimal distance to the outcome under a specific coordinatewise veto voting scheme, and (γ) it satisfies some monotonicity properties. Neither continuity nor decomposability is implied by strategy-proofness, but these are satisfied if we additionally impose Pareto-optimality or unanimity. Received: 18 October 1993/Accepted: 2 February 1996  相似文献   
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