Consumer-Phase Salmonella enterica serovar Enteritidis Risk Assessment for Egg-Containing Food Products

We describe a one-dimensional probabilistic model of the role of domestic food handling behaviors on salmonellosis risk associated with the consumption of eggs and egg-containing foods. Six categories of egg-containing foods were defined based on the amount of egg contained in the food, whether eggs are pooled, and the degree of cooking practiced by consumers. We used bootstrap simulation to quantify uncertainty in risk estimates due to sampling error, and sensitivity analysis to identify key sources of variability and uncertainty in the model. Because of typical model characteristics such as nonlinearity, interaction between inputs, thresholds, and saturation points, Sobol's method, a novel sensitivity analysis approach, was used to identify key sources of variability. Based on the mean probability of illness, examples of foods from the food categories ranked from most to least risk of illness were: (1) home-made salad dressings/ice cream; (2) fried eggs/boiled eggs; (3) omelettes; and (4) baked foods/breads. For food categories that may include uncooked eggs (e.g., home-made salad dressings/ice cream), consumer handling conditions such as storage time and temperature after food preparation were the key sources of variability. In contrast, for food categories associated with undercooked eggs (e.g., fried/soft-boiled eggs), the initial level of Salmonella contamination and the log10 reduction due to cooking were the key sources of variability. Important sources of uncertainty varied with both the risk percentile and the food category under consideration. This work adds to previous risk assessments focused on egg production and storage practices, and provides a science-based approach to inform consumer risk communications regarding safe egg handling practices.     

Adolescent sexuality: gay and lesbian issues

Dynamics and interventions with adolescents who express concern regarding gay/lesbian issues are described, with a focus both intrapsychic and social. Both psychological and emotional aspects of sexual preference, and cultural and social expectations for those who identify themselves as gay or lesbian are considered.     

Play in Mexican‐American mothers and toddlers is frequent,multimodal, and rich in symbolic content

Play offers rich opportunities for toddlers to develop motor, social, cognitive, and language skills, particularly during interactions with adult caregivers who may scaffold toddlers to higher levels of play than toddlers achieve on their own. However, research on play has narrowly focused on children from White, middle‐income backgrounds, leaving a dearth of knowledge about dyadic play in diverse cultural communities. We videorecorded 222 Mexican‐American mothers playing with their 2‐year‐old toddlers with a standard set of toys. Play behaviors were coded as nonsymbolic or symbolic (play type) and as expressed through manual, verbal, or multiple channels (play modality). Play between toddlers and mothers was frequent, high in symbolic content, and toddler play closely corresponded with mother play in type and modality: Toddlers’ nonsymbolic play related to mothers’ nonsymbolic play; toddlers’ symbolic play related to mothers’ symbolic play; toddlers’ manual play related to mothers’ manual play; and toddlers’ multimodal play related to mothers’ multimodal play. Play in Mexican‐American mothers and toddlers is frequent, multimodal, and symbolically rich, offering new directions for future research and practice.     

TEACHING THE PRODUCTION/OPERATIONS MANAGEMENT CORE COURSE: INTEGRATING LOGISTICS PLANNING ACTIVITIES

This paper discusses the benefits of restructuring the introductory undergraduate production and operations management (pom) course to improve its pedagogical effectiveness and to better convey the importance of integrating logistics planning activities. The introduction of a dynamic integrative semester-long case study which involves students in applying pom concepts and tools through a simulation game is reported.     

AIDS: developing a primary health care task force

As the number of people with AIDS increases, the number of people impacted by the AIDS crisis will also increase. Larger metropolitan areas have already responded to the crisis with various services (Deuchar, 1984); but the disease has yet to fully impact on smaller cities and towns. The formation of community service groups to cope with the AIDS crisis is a virtual necessity in health care preparation for persons with AIDS. The experience of the Fort Wayne AIDS Task Force reflects the potential of any community to utilize the existing resources in the gay and lesbian community, health and social service professions, and among family and friends of persons with AIDS. Consultation and resources are available through local and state boards of health, as well as local social service and health personnel currently dealing with the AIDS crisis.     

Consumer Phase Risk Assessment for Listeria monocytogenes in Deli Meats

The foodborne disease risk associated with the pathogen Listeria monocytogenes has been the subject of recent efforts in quantitative microbial risk assessment. Building upon one of these efforts undertaken jointly by the U.S. Food and Drug Administration and the U.S. Department of Agriculture (USDA), the purpose of this work was to expand on the consumer phase of the risk assessment to focus on handling practices in the home. One-dimensional Monte Carlo simulation was used to model variability in growth and cross-contamination of L. monocytogenes during food storage and preparation of deli meats. Simulations approximated that 0.3% of the servings were contaminated with >10(4) CFU/g of L. monocytogenes at the time of consumption. The estimated mean risk associated with the consumption of deli meats for the intermediate-age population was approximately 7 deaths per 10(11) servings. Food handling in homes increased the estimated mean mortality by 10(6)-fold. Of all the home food-handling practices modeled, inadequate storage, particularly refrigeration temperatures, provided the greatest contribution to increased risk. The impact of cross-contamination in the home was considerably less. Adherence to USDA Food Safety and Inspection Service recommendations for consumer handling of ready-to-eat foods substantially reduces the risk of listeriosis.     

The dynamics of hapū research relationships

Abstract

The Whakaki Lake Trust has a long history of being an active kaitiaki of Whakaki Lake and has developed a hapū-based restoration and enhancement programme at the Lake property. Part of this programme has involved working with a range of external agencies and researchers. Research relationships have become an important part of the restoration process to build the capability and capacity of hapū to execute activities associated with restoration. In addition, relationships have provided an opportunity to strengthen and expand the knowledge base that hapū can draw upon to inform ecological restoration and resource management decisions. Some of these relationships have been adversarial and a source of much frustration. As a consequence the Trust has developed very clear expectations and policy around working with others. My experience of developing a doctoral research project with Whakaki Lake Trust is used here to discuss hapū expectations of research and resultant academic dilemmas.     

Penalized Maximum Likelihood Estimator for Normal Mixtures

The estimation of the parameters of a mixture of Gaussian densities is considered, within the framework of maximum likelihood. Due to unboundedness of the likelihood function, the maximum likelihood estimator fails to exist. We adopt a solution to likelihood function degeneracy which consists in penalizing the likelihood function. The resulting penalized likelihood function is then bounded over the parameter space and the existence of the penalized maximum likelihood estimator is granted. As original contribution we provide asymptotic properties, and in particular a consistency proof, for the penalized maximum likelihood estimator. Numerical examples are provided in the finite data case, showing the performances of the penalized estimator compared to the standard one.     

中国古代慈善事业的发展特点

中国古代慈善事业在漫长的历史发展过程中不但逐渐形成了庞杂而丰富的思想体系,而且其慈善主体也实现了从最初单纯的国家慈善到以国家慈善为主、宗族慈善和宗教慈善为重要补充的多元化发展过程。另外,中国古代慈善事业的发展轨迹还明显具备与整个中国古代社会兴衰相表里的重要特点。