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991.
Our objective was to evaluate the effect that complexity in the form of different levels of spatial, population, and contact heterogeneity has in the predictions of a mechanistic epidemic model. A model that simulates the spatiotemporal spread of infectious diseases between animal populations was developed. Sixteen scenarios of foot‐and‐mouth disease infection in cattle were analyzed, involving combinations of the following factors: multiple production‐types (PT) with heterogeneous contact and population structure versus single PT, random versus actual spatial distribution of population units, high versus low infectivity, and no vaccination versus preemptive vaccination. The epidemic size and duration was larger for scenarios with multiple PT versus single PT. Ignoring the actual unit locations did not affect the epidemic size in scenarios with multiple PT/high infectivity, but resulted in smaller epidemic sizes in scenarios using multiple PT/low infectivity. In conclusion, when modeling fast‐spreading epidemics, knowing the actual locations of population units may not be as relevant as collecting information on population and contact heterogeneity. In contrast, both population and spatial heterogeneity might be important to model slower spreading epidemic diseases. Our findings can be used to inform data collection and modeling efforts to inform health policy and planning. 相似文献
992.
Alison Edwards Nancy Eisenberg Tracy L. Spinrad Mark Reiser Natalie D. Eggum‐Wilkens Jeffrey Liew 《Social Development》2015,24(1):76-94
The purpose of this study was to examine whether dispositional sadness predicted children's prosocial behavior and if sympathy mediated this relation. Constructs were measured when children (n = 256 at time 1) were 18, 30, and 42 months old. Mothers and non‐parental caregivers rated children's sadness; mothers, caregivers, and fathers rated children's prosocial behavior; sympathy (concern and hypothesis testing) and prosocial behavior (indirect and direct, as well as verbal at older ages) were assessed with a task in which the experimenter feigned injury. In a panel path analysis, 30‐month dispositional sadness predicted marginally higher 42‐month sympathy; in addition, 30‐month sympathy predicted 42‐month sadness. Moreover, when controlling for prior levels of prosocial behavior, 30‐month sympathy significantly predicted reported and observed prosocial behavior at 42 months. Sympathy did not mediate the relation between sadness and prosocial behavior (either reported or observed). 相似文献
993.
994.
The management of safety culture in international and culturally diverse organizations is a concern for many high‐risk industries. Yet, research has primarily developed models of safety culture within Western countries, and there is a need to extend investigations of safety culture to global environments. We examined (i) whether safety culture can be reliably measured within a single industry operating across different cultural environments, and (ii) if there is an association between safety culture and national culture. The psychometric properties of a safety culture model developed for the air traffic management (ATM) industry were examined in 17 European countries from four culturally distinct regions of Europe (North, East, South, West). Participants were ATM operational staff (n = 5,176) and management staff (n = 1,230). Through employing multigroup confirmatory factor analysis, good psychometric properties of the model were established. This demonstrates, for the first time, that when safety culture models are tailored to a specific industry, they can operate consistently across national boundaries and occupational groups. Additionally, safety culture scores at both regional and national levels were associated with country‐level data on Hofstede's five national culture dimensions (collectivism, power distance, uncertainty avoidance, masculinity, and long‐term orientation). MANOVAs indicated safety culture to be most positive in Northern Europe, less so in Western and Eastern Europe, and least positive in Southern Europe. This indicates that national cultural traits may influence the development of organizational safety culture, with significant implications for safety culture theory and practice. 相似文献
995.
Current research recognizes that the HIV pandemic uniquely impacts women, as they are socially and biologically more vulnerable to the infection. However, present measurement strategies focus on assessing the level of HIV infection among women, rather than inequality in the distribution of HIV cases by gender in less‐developed nations. In this study, we compare the cross‐national determinants of the level of female HIV prevalence to the determinants of the percentage of HIV cases among women. Ordinary least squares (OLS) regressions suggest that the predictors of female HIV differ across the two measures, where aspects of female empowerment and female access to health resources are more influential in explaining the distribution of HIV cases across gender than the level of female HIV prevalence. These results suggest that analyzing the distribution of HIV cases by gender is a more appropriate way to measure gender disparities in the HIV pandemic. Therefore, future research should be cautious to consider the implications of investigating levels of HIV versus the distribution of HIV cases across populations. 相似文献
996.
997.
Trait Predictors of Aggression and Crash‐Related Behaviors Across Drivers from the United Kingdom and the Irish Republic
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Aggressive driving is acknowledged as a contributor to motor vehicle crashes. This study explored a theoretical model of aggressive expression and crash‐related outcomes using self‐report data collected, using an online questionnaire, from drivers in the United Kingdom and the Republic of Ireland. The proposed model tested whether the personality traits of boredom proneness, sensation seeking, and impulsivity, coupled with trait driving anger, predicted aggressive driving; and whether aggressive driving predicted crash‐related outcomes (loss of concentration and control, near misses, and moving violations). The structural model was confirmed, with aggressive expressions of anger being found to mediate the relationships driving anger and impulsivity had with the crash‐related outcomes. Multigroup invariance analysis showed that the model remained invariant across drivers from the United Kingdom and Ireland, suggesting that the contributing factors for aggressive expression and crash involvement are similar across both countries. When self‐reported crash‐related conditions were compared between drivers in the United Kingdom and Ireland, drivers in the United Kingdom reported more aggressive driving, more minor crashes, more incidents of road rage, and more frequent losses of concentration and vehicle control. 相似文献
998.
Comparing UK and Other Western Countries' Health Expenditure,Relative Poverty and Child Mortality: Are British Children Doubly Disadvantaged?
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We examined the UK's effectiveness in reducing Child Mortality with 20 other Western countries, in the context of their national health expenditures, and, relative poverty — measured by ‘Income Inequality’ the gap between top and bottom 20 per cent of income. W.H.O. Child (0–14) Mortality Rates (CMR) and GDP Expenditure on Health (% GDPHE) were examined and a cost‐effectiveness ratio calculated, which is the reduced CMR over the period divided by average GDPHE. The highest average % GDPHE was USA at 13.2 per cent; the UK's 7.3 per cent was equal lowest. The widest Income Inequality was USA 8.5 times; the UK at 7.2 was third widest. The highest CMR was the USA 2436 per million (pm), the UK's 1630 pm, although representing a fall of 62 per cent was fourth highest. However, UK cost‐effectiveness ratio (1: 350) was eighth best of 21 countries. Only Income Inequality correlated significantly with CMR. UK CMR fell significantly more than five countries but ten others declined more. If UK deaths had been at the average of the 17 countries with lower CMR, there would have been 1827 fewer deaths. British children's poverty and health expenditure means they and their services are doubly disadvantaged although the NHS relatively achieved more with comparatively less. 相似文献
999.
Kai Sun Gary F. Krause Foster L. Mayer Mark R. Ellersieck Asit P. Basu 《Risk analysis》1995,15(2):247-252
In acute toxicity testing, organisms are continuously exposed to progressively increasing concentrations of a chemical and deaths of test organisms are recorded at several selected times. The results of the test are traditionally summarized by a dose-response curve, and the time course of effect is usually ignored for lack of a suitable model. A model which integrates the combined effects of dose and exposure duration on response is derived from the biological mechanisms of aquatic toxicity, and a statistically efficient approach for estimating acute toxicity by fitting the proposed model is developed in this paper. The proposed procedure has been computerized as software and a typical data set is used to illustrate the theory and procedure. The new statistical technique is also tested by a data base of a variety of chemical and fish species. 相似文献
1000.
Abstract This paper assesses the effects of the community sex ratio on black family formation and family structure in nonmetropolitan parishes in Louisiana. As predicted, the sex ratio is found to have strong positive effects on marriage prevalence for black women, the prevalence of husband and wife families for black families, and the percentage of black children residing in husband and wife families and strong negative effects on the nonmarital fertility ratio for black women. Thus, we conclude that the sex ratio hypothesis should be given greater prominence in discussions of changes in black family structure and that sex ratio effects should be taken into account when framing policies aimed at ameliorating social problems attendant to high relative incidence of nonmarital births and single-parent, female-headed families with young children (e.g., poverty). We also note that, while the literature overwhelmingly concentrates on black family structure in urban areas, changes in the black family are equally pronounced in nonmetropolitan areas suggesting that explanations emphasizing the dynamics of urban ghettos may be too narrow. 相似文献