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21.
This research is the first to examine the prevalence and dynamics of non-Hispanic white natural decrease in fine scale subregional units of the United States. In 2015, more non-Hispanic Whites died than were born in 65 percent of the US counties. This is the highest incidence of non-Hispanic white natural decrease ever reported. It results from a complex interaction among fertility, mortality, and migration over a protracted period. Spatial regression is used to identify three critical variables (over-65 population, child–women ratio, and women of childbearing age) that are the immediate demographic causes of this natural decrease. The timely, factual information in this paper provides a demographic context for analysis of the social, political, and policy implications of this emergent demographic phenomenon.  相似文献   
22.
Lot streaming is the process of splitting a job into sublots so its operations can be overlapped and its progress accelerated. We present a computationally efficient procedure for solving the m-machine, two-sublot problem, and we discuss the bottleneck insights that emerge from the analysis. We also examine heuristic approaches for more than two sublots and discuss computational results for these procedures.  相似文献   
23.
运用经济分析法学的理论和方法,对我国行政立法进行成本效益分析,对节约行政立法成本、提高行政立法效益具有重要意义。行政立法应当处理好自身成本与社会成本的关系,重视机会成本、边际成本分析和经济效益、社会效益分析。应当通过树立立法效益意识、健全立法机制、增强立法民主性等途径提高行政立法效益。只有收益大于成本的行政立法才具有经济合理性,而经济合理性是衡量行政立法正当性的重要标准之一。  相似文献   
24.
The responses obtained from response surface designs that are run sequentially often exhibit serial correlation or time trends. The order in which the runs of the design are performed then has an impact on the precision of the parameter estimators. This article proposes the use of a variable-neighbourhood search algorithm to compute run orders that guarantee a precise estimation of the effects of the experimental factors. The importance of using good run orders is demonstrated by seeking D-optimal run orders for a central composite design in the presence of an AR(1) autocorrelation pattern.  相似文献   
25.
Social Indicators Research - This paper addresses the following questions: Overall, on average, how did child and youthwell-being in the United States of Americachange in the last quarter of the...  相似文献   
26.
This study examined the role of three spiritual responses to divorce for psychological adjustment: appraising the event as a sacred loss/desecration, engaging in adaptive spiritual coping, and experiencing spiritual struggles. A sample of 100 adults (55% female) was recruited through public divorce records. Most appraised their divorce as a sacred loss/desecration (74%), experienced spiritual struggles (78%), and engaged in adaptive spiritual coping (88%). Appraisals of sacred loss/desecration and spiritual struggles were tied to higher levels of depression. Adaptive spiritual coping was tied to greater posttraumatic growth. Spiritual coping and struggles each contributed uniquely to adjustment beyond parallel forms of nonspiritual coping and struggles and mediated links between viewing the divorce as a sacred loss/desecration and depression.  相似文献   
27.
28.
Our understanding of the underlying demographic components of population change in new Hispanic destinations is limited. In this paper, we (1) compare Hispanic migration patterns in traditional settlement areas with new growth in emerging Hispanic destinations; (2) examine the role of immigration vis‐à‐vis domestic migration in spurring Hispanic population redistribution; and (3) document patterns of migrant selectivity, distinguishing between in‐migrants and non‐migrant Hispanics at both the origin and destination. We use several recent datasets, including the 1990 and 2000 Public Use Microdata Samples (which include new regional geocodes), and the 2005 and 2006 files of the American Community Survey. Our results document the widespread dispersion of the Hispanic population over the 1990–2006 period from established Hispanic gateways into new Hispanic areas and other parts of the country. Nearly one‐half of Hispanic net migration in new destinations comes from domestic gains. In contrast, both established and other Hispanic areas depend entirely on immigration, with each losing domestic migrants to high growth areas. Migrant flows also are highly differentiated by education, citizenship, and nativity. To fully understand the spatial diffusion of Hispanics requires a new appreciation of the complex interplay among immigration, internal domestic migration, and fertility.  相似文献   
29.
Urbanization is a process that heavily alters marine and terrestrial environments, though terrestrial urban ecosystems have been studied far more intensively. Terrestrial studies suggest that urbanization can facilitate mesopredators by enhancing food and shelter resources and reducing predation pressure from apex consumers. This in turn has considerable consequences for ecological communities. We evaluated spatial distribution patterns and habitat-use of the marine mesopredator, giant Pacific octopus (Enteroctopus dofleini), relative to terrestrial urbanization intensity in Puget Sound, Washington, USA. Using field surveys and citizen-contributed data for E. dofleini, we examined whether: (1) Distribution was related to urbanization, (2) Abundance was related to the extent of benthic anthropogenic debris, and (3) Diet differed as a function of urbanization and den cover. Our results suggest that urbanization impacts may differ with depth. Mixed-effects logistic regression model estimates for the probability of occurrence increased with urbanization in deep-water (> 24 m), and decreased with urbanization in shallow water (< 18 m). Accompanying field surveys indicated that E. dofleini abundance was correlated with the number of benthic anthropogenic debris items, and that E. dofleini diets were not affected by urbanization intensity or den cover. Though E. dofleini may be synanthropic within certain urban environments, the mechanisms driving this pattern likely differ from those affecting common urban mesopredators on land, with den provisioning from man-made structures being more important than altered food resources.  相似文献   
30.
The researchers examined differential outcomes related to two distinct motivations for withdrawal (preference for solitude and shyness) as well as the possibility that support from important others (mothers, fathers, and best friends) attenuate any such links. Adolescents (159 males, 171 females) reported on their motivations to withdraw, internalizing symptoms, and relationship quality in eighth grade, as well as their anxiety and depression in ninth grade. Using structural equation modeling, the authors found that maternal support weakened the association between shyness and internalizing problems; friend support weakened the association between preference for solitude and depression; and friend support strengthened the association between shyness and depression. Results suggest that shy adolescents may not derive the same benefits from supportive friendships as their typical peers.  相似文献   
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