This paper proposes new models for locating emergency medical services (EMS) by incorporating survival functions for capturing multiple-classes of heterogeneous patients. The Maximal Expected Survival Location Model for Heterogeneous Patients (MESLMHP) aims to maximize the overall expected survival probability of multiple-classes of patients, whereby different classes could be defined according to agreed patient categories based on response time targets, or by capturing differing medical conditions each with a corresponding survival function. Furthermore, we propose and demonstrate an approximation approach to solving the extended stochastic version of MESLMHP, which utilizes queuing theory to permit the modeling of congestion and utilization at each ambulance station, and does not require assumptions to be made on the utilization of ambulances. Both models are demonstrated using data from the ambulance service in Wales. We show that our multiple outcome measures and survival-maximizing approach, rather than one based on average response time targets alone or a single patient class provides more effective EMS ambulance allocations. 相似文献
Although numerous studies document a link between child sexual abuse and later sexual assault perpetration in men, little research has examined why this relationship exists. One potential mechanism may be emotional regulation difficulties. The current study utilizes a college sample of 132 men to examine the mediating role of emotion regulation difficulties on the relationship between experiencing child sexual abuse and later sexual aggression. Although emotion regulation difficulties in general was not significantly related to sexual aggression, one facet, impulse control difficulties, emerged as a significant mediator of the relationship between child sexual abuse and sexual aggression. Intervention programs should focus on the care that children receive following sexual abuse, with particular emphasis on how emotion regulation abilities may be impacted. 相似文献
The main objective of this study was to determine how stream salamander assemblages and species respond to varying levels of impervious surface cover within Maryland’s Piedmont physiographic province. We sampled stream salamanders in 21 first-order streams located in watersheds representing a range of impervious surface cover (0–24 %) across the northeastern part of Maryland’s Piedmont region. Habitat data, including stream substrate and riparian characteristics, were measured at each site. Eurycea bislineata was the predominant species of stream salamander encountered during this study (> 99 % of individuals) and most of these individuals were larvae (> 92 %). Consequently, statistical analysis was limited to E. bislineata larvae. We were unable to detect a difference in E. bislineata abundances or body mass index’s among varying levels of impervious surface cover % or any individual site habitat variables alone. These results suggest that in smaller watersheds within the Piedmont of Maryland, local habitat variables, in conjunction with land use variables, are necessary in determining the abundance and body mass index of E. bislineata larvae populations. This study makes a strong case for halting the over-simplification of the relationship between urbanization and the presence/abundance of stream salamanders.
According to cultural theorist Pierre Bourdieu, social class is defined by the interplay and operation of various forms of capital, within the set of durable and objective relations in which the classed subject is located. Informed by Bourdieu's understanding of social class, this article details the empirical dimensions of upper‐middle‐class familial involvement at the Valley View Swim and Tennis Club. An institution prefigured on the practice and development of important physical skills, Valley View represents a site for the complex interplay of capitals (economic, social, cultural, and physical) complicit in the preservation and reproduction of members' upper‐middle‐class habitus, and corresponding elevated and privileged social status. Specifically, we discuss the findings of ethnographic fieldwork focused on the acquisition, transmission, and conversion of economic, social, cultural, and physical capital in and through member families' club involvement. We argue that Valley View operates as a distinctive cultural field, wherein embodied techniques and expressions of class‐based power and privilege contribute to the reproduction of social class differences, boundaries, and hierarchies, in such a way as to render them natural, and largely unacknowledged, effects of being. 相似文献
The aim of this study was to develop a modified quantitative microbial risk assessment (QMRA) framework that could be applied as a decision support tool to choose between alternative drinking water interventions in the developing context. The impact of different household water treatment (HWT) interventions on the overall incidence of diarrheal disease and disability adjusted life years (DALYs) was estimated, without relying on source water pathogen concentration as the starting point for the analysis. A framework was developed and a software tool constructed and then implemented for an illustrative case study for Nepal based on published scientific data. Coagulation combined with free chlorine disinfection provided the greatest estimated health gains in the short term; however, when long‐term compliance was incorporated into the calculations, the preferred intervention was porous ceramic filtration. The model demonstrates how the QMRA framework can be used to integrate evidence from different studies to inform management decisions, and in particular to prioritize the next best intervention with respect to estimated reduction in diarrheal incidence. This study only considered HWT interventions; it is recognized that a systematic consideration of sanitation, recreation, and drinking water pathways is important for effective management of waterborne transmission of pathogens, and the approach could be expanded to consider the broader water‐related context. 相似文献
Urban-associated changes can have immediate or long-term consequences on animal populations. Such changes may be assessed through parasite prevalence and abundance in wildlife hosts, as urbanization can influence parasitism and disease transmission in wildlife. Snakes are widespread and diverse vertebrates that often persist in urban environments; however, parasitism of snakes in urban environments has yet to be studied, leaving the roles of snakes in parasite transmission uncharacterized. Field ecology, microscopy, molecular techniques, and geographic information science (GIS) were integrated to characterize parasitism of snakes in an urban old-growth forest park. The species, sex, mass, length, location, and prevalence of ecto-, hemo-, and fecal parasites were determined for 34 snakes of 6 species. Ectoparasites (mite), hemoparasites (Hepatozoon spp.), and fecal parasites (Entamoeba spp., Trichomonas spp., Strongloides spp., and an unidentified helminth) were detected in snakes and 64.7?% of snakes were infected by at least one of these parasites. Parasite infections were generally not related to the sex, age, or body condition of snakes. The locations of infected snakes were used to produce risk maps indicating where parasite prevalence is predicted to be greatest. The analysis of these maps indicated that snakes with fecal parasites were closer than non-infected snakes to the edge of the forest. This study confirms that snakes may be important parasite hosts or reservoirs in parasite transmission pathways in urban environments and it provides an integrative multidisciplinary approach that may be used to monitor parasitism dynamics in other urban wildlife areas. 相似文献
Welfare state studies are usually motivated by one or both of two concerns: programme effects on the incidence of poverty, and the possibility of perverse incentive effects. Most research has been comparative, using cross‐national indicators from the Organisation for Economic Co‐operation and Development and other international organizations. That research often contrasts the generosity of programmes in a number of European countries and the lack of it in the USA. Focusing on income transfers after job‐loss, in this article we critically examine the comparative evidence on US welfare state generosity and then use the Panel Study of Income Dynamics (PSID) to estimate what happens to job‐losers' incomes. The comparative analysis suggests conclusions more nuanced than found in much of the literature. The PSID analysis shows how the income effects of job‐loss vary across job‐losers and suggests that the role of unemployment compensation programmes in supporting incomes may be overstated. 相似文献