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41.
Hypothesized risk factors for men's and women's clinically significant intimate partner violence (CS‐IPV) from four ecological levels (i.e., individual, family, workplace, community) were tested in a representative sample of active‐duty U.S. Air Force members (N = 42,744). When considered together, we expected only individual and family factors to account for unique variance in CS‐IPV perpetration. Hypothesized factors from all four ecological levels were related to men's CS‐IPV perpetration bivariately, but, as expected, only individual and family factors accounted for unique variance across ecological levels. For women, only risk factors from the individual and family levels were significantly related to CS‐IPV perpetration even bivariately. Results imply somewhat different risk profiles across gender and identify ecological risk factors of men's CS‐IPV not previously studied.  相似文献   
42.
Abstract

Health science students, along with the health professionals they hope to become, are at increased risk for certain occupational injuries and illnesses. One of these risks is occupational exposure to blood-borne pathogens, such as human immunodeficiency virus (HIV) and hepatitis, which may result in severe illnesses or even death. Two case studies demonstrate postexposure care of exposed individuals at the University of Texas Medical Branch Student Health Services before and after policy changes and prevention strategies were strengthened in response to exposure incidents.  相似文献   
43.
This study’s objective was to explore the influence of delinquent peer exposure, on the relationship between male youths’ histories of trauma, anger, and violent behavior. Using a nationally representative sample of male adolescents aged 12–17 and self report interviews, information was gathered on their levels of exposure to violence, stressful life events (SLE), anger, depression, delinquent peer exposure, and violent behavior. Results of a moderation analyses revealed that youth who reported higher levels of exposure to trauma, anger, and delinquent peers were at an increased risk for anger and for violent offending. Delinquent peer exposure exerted a significant interaction effect on the relationship between anger and violent offending. The implications for prevention and intervention efforts are delineated.  相似文献   
44.
45.
A quantitative assessment of the exposure to Listeria monocytogenes from cold-smoked salmon (CSS) consumption in France is developed. The general framework is a second-order (or two-dimensional) Monte Carlo simulation, which characterizes the uncertainty and variability of the exposure estimate. The model takes into account the competitive bacterial growth between L. monocytogenes and the background competitive flora from the end of the production line to the consumer phase. An original algorithm is proposed to integrate this growth in conditions of varying temperature. As part of a more general project led by the French Food Safety Agency (Afssa), specific data were acquired and modeled for this quantitative exposure assessment model, particularly time-temperature profiles, prevalence data, and contamination-level data. The sensitivity analysis points out the main influence of the mean temperature in household refrigerators and the prevalence of contaminated CSS on the exposure level. The outputs of this model can be used as inputs for further risk assessment.  相似文献   
46.
A Perspective on Dioxin Emissions from Municipal Solid Waste Incinerators   总被引:2,自引:0,他引:2  
This paper discusses the following key issues concerning human exposure to dioxins and furans emitted from typical, modern MSW incinerators: (1) Are MSW incinerators the major source of PCDD/PCDF input into the environment? (2) Are environmental concentrations around MSW incinerators substantially elevated relative to background levels? And (3) are MSW incinerators the major source of human exposure to PCDDs and PCDFs? Current scientific evidence indicates that (1) combustion sources in general (including steel mills, copper smelting plants, motor vehicles, pulp and paper mills, and MSW incinerators) are major sources of PCDD/PCDF input in the environment; (2) environmental concentrations of PCDDs and PCDFs around operating MSW incinerators are not substantially elevated; and (3) 99% of human exposure to PCDDs and PCDFs is from background contamination, even for individuals living near a modern MSW incinerator.  相似文献   
47.
Using distributions of time spent at various ventilation levels, ranges of inhalation exposure in the population can be established. Distributions of exposure time were determined using results of a study by the California Air Resources Board (CARB) which focused on time spent by humans participating in various activities and the locations where the activities occurred. The daily at-home activities from the CARB study were assigned to one of three ventilation levels, generating aggregate time periods. Distinct age and gender populations were identified, and distributions for aggregate time were established for these populations at each of the ventilation levels. In addition to aggregate time spent at home, distributions for various ages and genders were established for aggregate time spent at school and work. By combining distributions of aggregate time with corresponding ventilation rates, the distribution of inhalation rates can be established for at home, at work, and at school exposures.  相似文献   
48.
In reliability analysis, accelerated life-testing allows for gradual increment of stress levels on test units during an experiment. In a special class of accelerated life tests known as step-stress tests, the stress levels increase discretely at pre-fixed time points, and this allows the experimenter to obtain information on the parameters of the lifetime distributions more quickly than under normal operating conditions. Moreover, when a test unit fails, there are often more than one fatal cause for the failure, such as mechanical or electrical. In this article, we consider the simple step-stress model under Type-II censoring when the lifetime distributions of the different risk factors are independently exponentially distributed. Under this setup, we derive the maximum likelihood estimators (MLEs) of the unknown mean parameters of the different causes under the assumption of a cumulative exposure model. The exact distributions of the MLEs of the parameters are then derived through the use of conditional moment generating functions. Using these exact distributions as well as the asymptotic distributions and the parametric bootstrap method, we discuss the construction of confidence intervals for the parameters and assess their performance through Monte Carlo simulations. Finally, we illustrate the methods of inference discussed here with an example.  相似文献   
49.
Assessments of aggregate exposure to pesticides and other surface contamination in residential environments are often driven by assumptions about dermal contacts. Accurately predicting cumulative doses from realistic skin contact scenarios requires characterization of exposure scenarios, skin surface loading and unloading rates, and contaminant movement through the epidermis. In this article we (1) develop and test a finite-difference model of contaminant transport through the epidermis; (2) develop archetypal exposure scenarios based on behavioral data to estimate characteristic loading and unloading rates; and (3) quantify 24-hour accumulation below the epidermis by applying a Monte Carlo simulation of these archetypal exposure scenarios. The numerical model, called Transient Transport through the epiDERMis (TTDERM), allows us to account for variable exposure times and time between exposures, temporal and spatial variations in skin and compound properties, and uncertainty in model parameters. Using TTDERM we investigate the use of a macro-activity parameter (cumulative contact time) for predicting daily (24-hour) integrated uptake of pesticides during complex exposure scenarios. For characteristic child behaviors and hand loading and unloading rates, we find that a power law represents the relationship between cumulative contact time and cumulative mass transport through the skin. With almost no loss of reliability, this simple relationship can be used in place of the more complex micro-activity simulations that require activity data on one- to five-minute intervals. The methods developed in this study can be used to guide dermal exposure model refinements and exposure measurement study design.  相似文献   
50.
Two disparate statistics often cited for the Western United States raise concern about risks for developmental disabilities in Native American children. First, 13 of the states with the highest percentage of Native American population are located in the Western United States (U.S. Census Bureau, 2012 U.S. Census Bureau. (2012). The American Indian and Alaska Native Population: 2010 (U.S. Census Briefs, January, #C2010BR-10). Retrieved from http://www.census.gov/prod/cen2010/briefs/c2010br-10.pdf [Google Scholar]). Second, more than 161,000 abandoned hard-rock mines are located in 12 Western states (General Accounting Office, 2014 General Accounting Office. (2014, July 14). GAO-11–834T: Abandoned Mines. Information on the number of hardrock mines, cost of cleanup, and value of financial assurances. Statement of Anu K. Mittal, Director, Natural Resources and Environment Team, Testimony before the Subcommittee on Energy and Mineral Resources, Committee on Natural Resources, House of Representatives. Retrieved from http://www.gao.gov/products/GAO-11-834T [Google Scholar]). Moreover, numerous studies have linked low-level metals exposure with birth defects and developmental delays. Concern has emerged among tribal populations that metals exposure from abandoned mines might threaten development of future generations.  相似文献   
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