New Data,Strategies, and Insights for Listeria monocytogenes Dose‐Response Models: Summary of an Interagency Workshop, 2011

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.     

Whose space is it anyway? A study of young people's interaction with security guards in New South Wales

Abstract

Limited research has been conducted in relation to the impact of private policing on young people. Research has primarily focused on young people and their use of public space, their use of the street or the policing of working class families and their children. This paper outlines an investigation of young peoples use of public spaces and their experiences of security guards within the greater Sydney metropolitan area of New South Wales. The paper also outlines the experiences of shopping centre managers in relation to the management of young people within their centres. The research found that young people are over policed within public spaces and especially in shopping complexes. Young people are primarily over policed within these spaces because of the perceived fears other groups within the community hold in relation to young people, especially those in groups.     

An evaluation of the tandem configuration automated guided vehicle system

The performance of a tandem automated guided vehicle (AGV) system is compared with that of conventional AGV track systems. In the tandem system the track is divided into non-overlapping, single-vehicle closed loops. Using simulation it is shown that, because of trips requiring delivery across loops, the tandem system has a higher expected travel time per load and thus a greater average time in system. When the loads are delivered within the original loop only, the tandem system has a lower average time in system than in conventional systems, although the difference is modest. Track layout appears to influence the average time in system much more than docs the dispatching rule invoked. The success of the tandem system is highly dependent on approximately even AGV utilization, which may be difficult to obtain in practice.     

Rolling horizon master production schedule performance: A policy analysis

In this paper, a simulation experiment has been developed to examine the combined influence of the design, inventory and environmental factors on the cost performance of a rolling horizon master production schedule. Specifically, a 2 5 factorial design was used to examine the effects associated with three rolling schedule design policies, one inventory policy and one environmental condition of forecast error on MPS cost performance. The study was based on actual data from a paint company. Results suggest that the choice of appropriate lot-size and inventory policies have a significant influence on MPS costs and that there are indeed important interactions between these policies and other design factors of a rolling schedule.     

‘You Get More Respect,’ Reasons for Sex Among African American High School Youth: A Qualitative Study

ABSTRACT

African American adolescents continue to be disproportionately impacted by HIV, sexually transmitted infections (STIs), and unanticipated pregnancies. In-depth, face-to-face interviews among a convenience sample of 32 African American adolescents (16 male and 16 female) were used to explore the reasons why some adolescents decided to engage in sex while others chose to delay sexual debut. Data were analyzed using a thematic analysis. Among the overall sample, psychological motivations, external pressure, physical pleasure seeking, and relationship-related motivations were the major themes cited for engaging in sex by participants and their friends. External support, motivation to avoid negative consequences, not feeling ready or lacking interest in sex, and having negative views about sex were among the major reasons for delaying sex. Several of the emergent themes showed gender differences. Suggestions for future research include the need for sexual education, and STI/HIV prevention programs that are gender sensitive and flexible enough to accommodate multiple factors related to sexual debut.