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171.
Historically, child maltreatment has been seen as an issue warranting the involvement of the American government. However, over time, the definition of child maltreatment has changed; typically, maltreatment is often understood as a violation of the parental right to care for and protect a child. Consequently, the government, through systems such as child protective services is expected to be the acceptable parental alternative. As illustrated by the numerous negative outcomes experienced, it is clear that the system is not meeting the needs of abused and neglected children. This bureaucratic neglect is allowed to occur because of population primarily served by the child welfare system, the poor and families of color. In this way, dynamics of power and privilege manifest in the differing expectations of appropriate care between biological parents and the foster care system.  相似文献   
172.
There is mixed evidence in the existing literature on whether children are associated with greater subjective well-being, with the correlation depending on which countries and populations are considered. We here provide a systematic analysis of this question based on three different datasets: two cross-national and one national panel. We show that the association between children and subjective well-being is positive only in developed countries, and for those who become parents after the age of 30 and who have higher income. We also provide evidence of a positive selection into parenthood, whereby happier individuals are more likely to have children.  相似文献   
173.
We describe a new Monte Carlo algorithm for the consistent and unbiased estimation of multidimensional integrals and the efficient sampling from multidimensional densities. The algorithm is inspired by the classical splitting method and can be applied to general static simulation models. We provide examples from rare-event probability estimation, counting, and sampling, demonstrating that the proposed method can outperform existing Markov chain sampling methods in terms of convergence speed and accuracy.  相似文献   
174.
This article explores the obligations of presence behind work-related mobility for academics in internationalizing higher education systems. By further developing John Urry’s concept of ‘meetingness’, the article reveals how academics depend on corporeal and virtual mobility to create and maintain a networked professional life outside their own institution, which is crucial in the context of changing work conditions. Our insights are drawn from original qualitative research (42 interviews) in a Flemish and Danish context. The data reveal obligations of presence associated with an interrelated mix of functionality, and the construction of dense and sparse social networks that together support career success and work at the frontiers of academic knowledge. Despite the now well-recognized costs of corporeal mobility, obligations of presence result in virtual and corporeal mobility coexisting, rather than the former substituting for the latter. Virtual mobility is mainly used when conflicting obligations of presence exist, and as a means of sustaining networks over time given the processual nature of meetingness, rather than as a means to reduce levels of corporeal mobility.  相似文献   
175.
176.
Two-unit warm standby systems have been elaborately dealt within the literature. However, the study of standby systems with more than two units, though very relevant in state-of-the-art practical situations, has received little attention because of mathematical intricacies involved in analyzing them. Also, such systems have been studied assuming: (i) the lifetime or repair time of the units to be exponential, or (ii) the lifetime and repair time to be independent. The present contribution is an improvement in the state-of-the-art in the sense that three-unit warm standby system with dependent structure is shown to be capable of comprehensive analysis.  相似文献   
177.
We examine the psychometric and empirical properties of some commonly used survey-based measures of risk preferences in a population-based sample of 11,000 twins. Using a model that provides a general framework for making inferences about the component of measured risk attitudes that is not due to measurement error, we show that measurement-error adjustment leads to substantially larger estimates of the predictive power of risk attitudes, of the size of the gender gap, and of the magnitude of the sibling correlation. Risk attitudes are predictive of investment decisions, entrepreneurship, and drinking and smoking behaviors; are robustly associated with cognitive ability and personality; and our estimates are often larger than those in the literature. Our results highlight the importance of adjusting for measurement error across a wide range of empirical settings.  相似文献   
178.
Lawns are considered monocultures and lesser contributors to sustainability than diverse nature but are still a dominating green area feature and an important cultural phenomenon in cities. Lawns have esthetical values, provide playground, are potential habitat for species, contribute to carbon sequestration and water infiltration, but also increase pesticides, fertilization, are monocultures and costly to manage at the same time. To evaluate the potential impact of lawns, whether positive or negative, it is of interest to estimate the total lawn cover in cities and its change over time. This is not a straightforward process, e.g., because many lawns are small and covered by trees. In this study we review the existing literature of lawn cover in cities and the different methodologies used for cover estimation. We found both pros and cons with NDVI and LiDAR data as well as manually interpreted aerial photos. The total cover of lawns in three case study cities was estimated to 22.5%. By extrapolating these percentages to all Swedish cities lawn cover was estimated to 2589 km2 (0.6% of the terrestrial surface). The approximated total municipal management cost of lawns in all Swedish cities was 910,000,000 USD/ year. During 50 years lawn area almost doubled in relative cover and 56% of them were continuously managed. Since lawns constitute large parts of the urban greenery and are costly to manage it is highly relevant to consider their social, ecological and cultural value compared to alternatives, e.g., meadows with less intensive management.  相似文献   
179.
This article offers a new definition of military cultural competence based on a review of the literature. As a starting point, the defining characteristics of military culture is discussed and includes the chain of command, military norms, and military identity. Having laid this groundwork, the multidimensionality of military cultural competence—attitudinal, cognitive, behavior—is discussed. Clinical applications of these various competencies are provided.  相似文献   
180.
Parenting is a critical factor in substance abuse prevention. Positive parenting behaviors are identified as a protective factor for substance abuse among youth. Limited research exists that investigates the role of parenting practices on minority youth substance use. The present study seeks to examine correlates between parenting and recent alcohol use among African American youth. Specifically, to what extent do African American students report experiencing specific parenting behaviors that are measured by the National Household Survey on Drug Use and Health?, do specific parenting behaviors increase the risk of recent alcohol use among African American youth?, does the impact of parenting behaviors on recent alcohol use among African American youth differ based on sex (males and females) and age category (12–13, 14–15, and 16–17 years old) were examined in this study? Logistic regression analysis of the National Household Survey on Drug Use and Health was conducted to examine the research questions. Findings indicated that parenting behaviors was associated with recent alcohol among youth. Significant differences were found for males, females, 12–13, 14–15, and 16–17 years olds. Study findings demonstrate the importance of positive parenting behaviors in youth alcohol prevention. Program specialists may target parenting as a means of preventing and reducing youth alcohol use among African American youth.  相似文献   
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