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961.
We used data from the Birth to Twenty Cohort study to understand children’s receipt of financial support from their fathers in a low income, Black community in urban South Africa. Specifically, we (1) described fathers’ financial support over the life course of children; (2) estimated survival probabilities of receiving support for all children and not receiving support for children who experienced a parental union dissolution; and (3) identified factors that explained variation in the receipt of support after a union dissolution. Results suggest that most children received full or partial support throughout the life course. Furthermore, a high proportion of children received support after a union dissolution with much of the variation driven by pre-dissolution support, father’s education and the presence of extended kin.  相似文献   
962.
963.
Pollen specialization by solitary bees in an urban landscape   总被引:1,自引:1,他引:0  
Many polylectic bee species are known to specialize locally on one or a few pollen types to increase foraging efficiency. What is relatively unknown is how different landscapes influence foraging decisions, and whether habitat alteration, such as that resulting from urbanization, influences broad-scale foraging activities of bees. This study evaluates the type and diversity of pollen collected by two solitary bees that are common in Toronto, Ontario, Canada, the native Osmia pumila and the exotic O. caerulescens, sampled in trap nests set up in urban parks and gardens. We found that the dominant pollen in every successful brood cell was either of one widespread, cosmopolitan lawn-invasive plant species (Trifolium repens) or one of two wind-pollinated tree genera (Quercus spp. and Betula spp.). In combination, these three represented more than 90 % of all pollen collected by each bee species. Despite considerable overlap in the dominant pollen types collected by each bee species, the exotic O. caerulescens was significantly more specialized than the native O. pumila. Brood cells with Betula as the dominant pollen type were more pollen species-rich than those cells having Trifolium or Quercus as dominant, perhaps a result of the comparatively low protein content in Betula pollen.  相似文献   
964.
This investigation sought to elaborate Koerner and Fitzpatrick’s theory of family communication by testing two theoretical models of family communication patterns (FCP), child-to-parent inclusion of the other in the self (IOS), and relational maintenance. Participants included 374 young adults recruited from two universities in different regions of the United States. Results best supported a model positioning maintenance as a mediator of the association between FCP and IOS, as compared to an alternative model with IOS as a mediator of the association between FCP and maintenance. These findings extend Koerner and Fitzpatrick’s theory by highlighting communication as the means by which overarching family schemas influence relationship-specific schemas; additionally, they commend the self-expansion model as a useful theoretical approach to relational maintenance behavior in family contexts.  相似文献   
965.
966.
Global guidelines for physical activity are not being met by most of the world’s youths, adults, and older adults. Family and friends who engage in physical activity across generations derive emotional, social, cognitive, and physical benefits from their interaction. Youths depend on adult assistance to travel long distances, adults are encumbered with obligations to work, and older adults often live more than 200 miles from their extended families. Intergenerational physical activity is difficult because generations are distant and lead busy lifestyles. Remotely played exergames can connect family and friends for intergenerational physical activity. Internet exergaming can help to make physical activity convenient and enjoyable as well as eliminate the effect of distance on playing with family and friends.  相似文献   
967.
As employment becomes more precarious, and spells of displacement become more common across the labor market, many individuals are forced to make decisions about the speed at which they seek reemployment and the types of employment they will seek. Using repeated cross‐sectional data from various years of the Displaced Worker Supplement of the Current Population Survey, we examine the degree to which employer‐provided health insurance and organizational provision of advanced layoff warning helped workers—particularly those from earlier birth cohorts—navigate the labor market during a period of growing employment flexibility. Our results indicate that workers from older cohorts, rather than older chronological ages, suffered more from displacement in terms of longer unemployment spells and declines in job quality upon reemployment. Workers able to obtain a job with health insurance had shorter unemployment durations, while those displaced from jobs with health insurance remained unemployed for longer periods of time. Advance notice appears to reduce some of the disproportionately negative effects of displacement for older workers, perhaps by easing the shock of a psychological contract breach. Our findings point to the importance of historical and cultural factors in shaping labor market outcomes.  相似文献   
968.
Sociologists have examined how structural economic change affects household social organization and generation of household income from different sources. The introduction of elements of a market economy into rural Russia in the early 1990s provides a unique opportunity to examine these relationships. Much of the work on this topic, however, has been conducted in black earth zone, agriculturally dependent regions. Less attention has been given to non‐black‐earth zone, forest resource dependent regions. This article addresses this limitation by comparing the relationships between household income generation strategies and household social organization in a 2009 survey of villages in three forest resource dependent regions in northwest Russia with findings from a 2006 survey of households in nine agricultural regions of Russia. Income generated from enterprises based on household social organization—household labor and social helping networks—is substantially greater in agriculturally dependent than in forest resource dependent regions. We discuss the implications of these findings for understanding intranational regional differences in the relationship between economic systems, household social organization, and rural household economies as well as the obstacles facing policymakers and environmentalists who attempt to shift household income generation strategies away from an environmentally harmful lumber industry to income generation activities that are less harmful to the environment.  相似文献   
969.
We examine the process of Gentrification in two residential areas of Cologne, Germany: Deutz and Mülheim. The theory underlying the study is a phase (or stage) model of Gentrification in which indicators and their values are attributed to each phase. The hypotheses derived from the model pertain to changes in the social structure, rents and the spatial distribution of social groups such as “pioneers”, “gentrifiers” and “others”. We further assume both areas to be in different phases of Gentrification.  相似文献   
970.
Despite recent increases of psychosocial programs for pediatric chronic illness, few studies have explored their economic benefits. This study investigated the costs–benefits of a family systems‐based, psychosocial intervention for pediatric chronic illness (MEND: Mastering Each New Direction). A quasi‐prospective study compared the 12‐month pre–post direct and indirect costs of 20 families. The total cost for program was estimated to $5,320. Families incurred $15,249 less in direct and $15,627 less in indirect costs after MEND. On average, medical expenses reduced by 86% in direct and indirect costs, for a cost–benefit ratio of 0.17. Therefore, for every dollar spent on the program, families and their third payers saved approximately $5.74. Implications for healthcare policy and reimbursements are discussed.  相似文献   
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