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991.
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   
992.
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   
993.
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   
994.
Elementary students survey buildings in an extracurricular community service project to learn social studies and historic preservation. From these experiences students formed values and dispositions by engaging in a constructivist process of creating knowledge by examining their community. They gathered data, transformed it into information, and shared it with the larger community. Because students learned what community means in reality, not just reading about it, they had a different understanding of how they related to the place they called home. Examining these types of questions helped elementary students have significant experiences that helped them to connect community members with the importance of place. The built environment is the context for historic structures. Student engagement with the social studies curriculum allowed them to create investigations with architecture to broaden their understanding of their world.  相似文献   
995.
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   
996.
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   
997.
Studies regarding the effectiveness of homework assignments in cognitive‐behavioral treatments have demonstrated mixed results. This study investigated predictors of compliance with homework recommendations and the time‐varying relationship of recommendation completion with treatment response in a brief couples' intervention (= 108). More satisfied couples and couples with more motivation to change completed more recommendations, whereas couples with children completed fewer. The association between recommendation completion and treatment response varied with the passage of time, with the strongest effect observed 6 months after the intervention, but no discernible differences at 1 year postintervention. Couples that completed more recommendations experienced more rapid treatment gains, but even those couples doing substantially fewer recommendations ultimately realized equivalent treatment effects, although they progressed more slowly. Implications are discussed.  相似文献   
998.
999.
This paper reports the results of a quantitative 42-item survey that explored foster, adoptive, and kinship parents’ (N = 160) utilization of different types of respite services (formal, informal, and a mixture of formal and informal), as well as their impressions of the impact of respite care on aspects of their lives related to family cohesion and stability, caring for their children, and their personal wellbeing. An exploratory cross-sectional, survey design was used to assess both the formal and informal respite care experiences of the foster, adoptive, and kinship caregivers. Two-tailed Fisher’s exact tests were used to examine the relationship between the type of respite received and caregivers’ respite experiences. Findings indicated that parent experiences differed depending on the type of respite services they received. Specifically, parents who used a mixture of formal and informal respite reported positive experiences related to respite more frequently than the other two types of respite groups, while those who received only informal respite reported less benefit than others. Parents who used formal respite (either alone or mixed with informal respite) reported greater stress reduction. The greatest increase in family stability was reported by parents who received a mix of informal and formal respite. While this study revealed clear benefits for families to using both informal and formal respite services, the findings suggest that formal respite care was helpful to parents regardless of whether used alone or in combination with informal care.  相似文献   
1000.
Participatory action research is well documented with marginalized groups, but less is known about participatory action research with homeless youth. The use of youth led research as a methodology was examined among a population of homeless youth. Peer researchers (n = 10) reported on their experience utilizing youth led research methodology. Results indicate that youth led research is a promising methodology for use among homeless youth. Participants reported that the approach positively impacted the quality and quantity of data that could be collected from participants. Further, peer researchers reported individual benefits of feeling that participating in the project mattered, that people listened to them and that they had a voice.  相似文献   
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