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641.
The modern election campaign is a well-oiled machine. Campaigns are won by the smallest of margins. Strategists provide incentives for specific market segments, and potential voters are identified well before the writ is dropped. However, few questions are asked in those same war rooms when certain groups stay home – namely young people. Young people are largely ignored at election time, and in turn, those under 30 ignore elections. Drawing on 20 focus groups conducted in Canada in 2014, this paper compares politically engaged and less engaged communities of young people to learn how they feel about politics and political leaders. This effort builds a better understanding of why some communities of young people are less interested and engaged in politics which is vital to our understanding of turnout decline among youth, as it is these communities of young people who have almost entirely tuned out of political affairs.  相似文献   
642.

Niche partitioning reduces interspecific competition, facilitating coexistence. In urban ecosystems, however, habitat loss reduces species’ ability to spatially partition activity. Temporal partitioning may thus increase in urban areas as species, unable to avoid each other spatially, partition time to avoid competition. In Midwestern US cities, eastern gray squirrels (Sciurus carolinensis) and fox squirrels (S. niger) co-occur and compete for resources. We identified urban gray and fox squirrel activity patterns and how they vary with season, land cover, and among sites where they do and do not co-occur using camera-trap data. Both species’ activity patterns varied with season and canopy and impervious surface cover. Gray squirrel activity patterns varied in the presence of fox squirrels only in the fall, providing limited support for our temporal partitioning hypothesis. Temporal niche partitioning may thus play a role in supporting these species co-existence when competition is seasonally-elevated (e.g., fall hording), but appears less important in other seasons.

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VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - Geographic space or location is an important aspect of many research topics in the third sector. Methodological advances...  相似文献   
645.
High levels of prenatal alcohol exposure (PAE) result in significant cognitive deficits in children, but the exact nature of the dose-response relationship is less well understood. To investigate this relationship, data were assembled from six longitudinal birth cohort studies examining the effects of PAE on cognitive outcomes from early school age through adolescence. Structural equation models (SEMs) are a natural approach to consider, because of the way they conceptualise multiple observed outcomes as relating to an underlying latent variable of interest, which can then be modelled as a function of exposure and other predictors of interest. However, conventional SEMs could not be fitted in this context because slightly different outcome measures were used in the six studies. In this paper we propose a multi-group Bayesian SEM that maps the unobserved cognition variable to a broad range of observed outcomes. The relation between these variables and PAE is then examined while controlling for potential confounders via propensity score adjustment. By examining different possible dose-response functions, the proposed framework is used to investigate whether there is a threshold PAE level that results in minimal cognitive deficit.  相似文献   
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