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131.
Listeria monocytogenes is a leading cause of hospitalization, fetal loss, and death due to foodborne illnesses in the United States. A quantitative assessment of the relative risk of listeriosis associated with the consumption of 23 selected categories of ready‐to‐eat foods, published by the U.S. Department of Health and Human Services and the U.S. Department of Agriculture in 2003, has been instrumental in identifying the food products and practices that pose the greatest listeriosis risk and has guided the evaluation of potential intervention strategies. Dose‐response models, which quantify the relationship between an exposure dose and the probability of adverse health outcomes, were essential components of the risk assessment. However, because of data gaps and limitations in the available data and modeling approaches, considerable uncertainty existed. Since publication of the risk assessment, new data have become available for modeling L. monocytogenes dose‐response. At the same time, recent advances in the understanding of L. monocytogenes pathophysiology and strain diversity have warranted a critical reevaluation of the published dose‐response models. To discuss strategies for modeling L. monocytogenes dose‐response, the Interagency Risk Assessment Consortium (IRAC) and the Joint Institute for Food Safety and Applied Nutrition (JIFSAN) held a scientific workshop in 2011 (details available at http://foodrisk.org/irac/events/ ). The main findings of the workshop and the most current and relevant data identified during the workshop are summarized and presented in the context of L. monocytogenes dose‐response. This article also discusses new insights on dose‐response modeling for L. monocytogenes and research opportunities to meet future needs.  相似文献   
132.

In this paper our main objective is to investigate a deterministic inventory production lot-size model with a permissible delay in payment under a restriction. We analyse our deterministic inventory model under a restriction which will be assumed as the average inventory level. In fact we use in our analysis two approaches: the geometric programming approach; and the Lagrange method. Then a comparison between these two approaches is performed, which is our aim. Finally we deduce some previously published works of other researchers as special cases.  相似文献   
133.
What makes people perceive a leader as charismatic, and how do team leaders obtain performance outcomes from their followers? We examine leaders in times of organizational change and investigate the mechanisms through which leaders' change-promoting behaviors are associated with team performance. In a multilevel mediation model, we propose that the indirect relationship between change-promoting behaviors and team performance is sequentially transmitted through followers' perceptions of charisma and followers' commitment to change. A study of 33 leaders and 142 followers provides empirical support for the model, using multilevel structural equation modeling to analyze top-down relationships between leaders and followers and bottom-up relationships between followers and team outcomes. Results suggest that team leaders are perceived as more charismatic when they engage in change-promoting behaviors. These behaviors facilitate team performance through individual followers' perceived charisma and commitment to change.  相似文献   
134.
Despite renewed interest in traditional trait approaches to leadership and despite recent demographic trends towards an aging workforce, research on leaders' age as a specific demographic trait variable has remained surprisingly sparse and fragmented. This article provides a comprehensive review of the empirical literature on this issue. Although a body of research relating leaders' age with their behaviors and outcomes has emerged, the existing findings exhibit little consistency and lack theoretical coherence. Integrating theories of emotional aging with research on emotions and leadership, we therefore develop a novel, emotion-based framework that explicates key mechanisms and boundary conditions underlying age–leadership linkages. Moreover, we outline opportunities for further theoretical extensions and provide recommendations for future empirical work. Overall, this article paves new ground for contemporary research on leadership traits by highlighting the relevance of leaders' age, summarizing current knowledge on this issue, and providing new theoretical and empirical directions.  相似文献   
135.
"This study addressed the problem of the Moroccan immigration into Spain within the context of South-North movements, focusing on analyzing provisional data from the last immigrant regularization in the country completed during the end months of 1991."  相似文献   
136.
137.
This study examines the possibility that estimation of the effect of breast-feeding on infant survival is affected by selection bias, in that children who are healthier at birth may be more likely to be breast-fed. Data are from the 1976 Malaysian Family Life Survey. "Ordinary logit models for breast-feeding and survival are estimated, and the results suggest that selection is indeed present. For example, children of higher birth weight appear to be more likely to be breast-fed and likely to survive. In addition, weight at birth and the duration of breast-feeding appear to be linked." Using birth weight as an indicator for the child's health, the authors conclude that "the direct influence of breast-feeding on survival remains of overwhelming importance even after corrections for selection bias are made."  相似文献   
138.
Theory and Decision - We explore how risk preferences affect pro-social behavior under uncertainty. We analyze a modified dictator game in which the dictator can, by reducing her own sure payoff,...  相似文献   
139.
蒙古语多方言语音识别及共享识别模型探索   总被引:1,自引:0,他引:1  
通过语音输入方式准确识别蒙古语主要方言 ,并为其建立共享识别模型 ,对实现方言间的信息自动交换及语音识别技术的实用化具有实际意义。针对蒙古语多方言的语音特点 ,可以采取独立的或者共享识别模型进行识别。本文介绍的抽出初步模型和建立共享模型的方法 ,简便易行 ,但识别精度有待提高。文中探索了通过借用数据量和质较完备的语言的语音数据提高识别率的可能性。  相似文献   
140.
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