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371.
We estimate a mixed logit model of the demand for local news service. Results provide evidence that suggest the representative consumer values more diverse news, more coverage of multicultural issues, and more information on community news, and has a distaste for advertising. Demand estimates are used to calculate the impact on consumer welfare from a marginal decrease in the number of independent television stations that lowers the amount of diversity, multiculturalism, community news, and advertising. Consumer welfare decreases, but the losses are smaller in large markets. For example, small‐market consumers lose $45 million annually while large‐market consumers lose $13 million. (JEL C9, C25, L13, L82, L96) 相似文献
372.
Substance use among older youth transitioning from foster care: Examining the protective effects of religious and spiritual capital 下载免费PDF全文
Lionel D. Scott Jr. David R. Hodge Tony White Michelle R. Munson 《Child & Family Social Work》2018,23(3):399-407
Among older youth transitioning from the foster care system, this longitudinal study examined the association of religious and spiritual capital to substance use in the past year at age 19. Participants consisted of African American (N = 179) and White non‐Hispanic (N = 133) older youth in foster care. Drawing from social capital theory, it was posited that religious service attendance (a proxy for religious capital) and belief in a spiritual force (a proxy for spiritual capital) would be inversely associated with substance use. Multiple logistic regression results indicated support for the first and second hypothesis for White foster youth only. Among White foster youth, more frequent religious service attendance and greater belief in a spiritual force were associated with a lower likelihood of illegal substance and polysubstance use. No association between religious or spiritual capital and substance use was found among African American foster youth. The findings underscore the importance of conducting spiritual assessments to help ensure older foster youth who have strong religious or spiritual orientations are in environments where they are accommodated and supported. 相似文献
373.
Diversification gains in mean-variance efficiency derived from including real estate in financial asset portfolios are examined. Optimal financial and mixed-asset portfolios were generated by selecting from an investment universe including several distinct financial and real estate media. Deficiencies of previous studies were overcome by employing data with improved representativeness and comparability. The efficient mixed-asset portfolios dominated the efficient financial asset portfolios implying that purely financial asset diversification is inefficient. The optimal mixed-asset portfolio prescribed that approximately two-thirds of the investment wealth be allocated to real estate and one-third to the financial media. 相似文献
374.
Landscape urbanization threatens plant phylogenetic diversity in the Brazilian Atlantic Forest 总被引:1,自引:0,他引:1
Valdecir Silva-Junior Danielle G. Souza Rubens T. Queiroz Luiz G. R. Souza Elâine M. S. Ribeiro Bráulio A. Santos 《Urban Ecosystems》2018,21(4):625-634
Urbanization causes species loss around the world, but its effects on phylogenetic diversity are poorly known in tropical forests. Using a patch-landscape approach in an urbanizing region of the Brazilian Atlantic Forest, we tested whether the increase in landscape urbanization reduces plant species density, phylogenetic richness and divergence, and increases the relatedness among co-occurring individuals and species. We assessed plant responses to urbanization in adult (diameter at breast height?>?10 cm) and sapling communities (2.5–10 cm diameter) separately, as saplings are proxies of the future flora. We sampled 2860 woody plants belonging to 155 species in nine circular landscapes with urbanization level varying from 0% to 45%, and estimated the relatedness among the species that have increased and decreased in relative abundance in more urbanized landscapes (winner and losers, respectively). As expected, species density and phylogenetic richness decreased with the increase in urbanization. These responses were consistent for adult and sapling communities, suggesting a persistent loss of species and lineages in more urbanized landscapes. Contrary to our expectations, phylogenetic divergence and structure did not respond to urbanization, indicating that the more urbanized landscapes still retain much evolutionary history. However, because the relatedness among winners was greater than among losers, it is likely that the phylogenetic divergence gradually reduces and the relatedness increases, resulting in impoverished forests with uncertain ability to provide ecosystem services such as carbon storage and pest control. This environmental cost should be taken into account to align urban sprawl with biodiversity conservation. 相似文献
375.
Anna L. Hotton Lance Keene Dennis E. Corbin John Schneider Dexter R. Voisin 《Journal of gay & lesbian social services》2018,30(1):64-81
Black gay men must navigate identities and stigmas related to being gay and Black, and report higher HIV incidence relative to their White male counterparts although they report lower rates of drug use and risky sexual behaviors. This study examined whether closeness to the gay or Black community correlated with HIV-related risk and protective behaviors. Data were drawn from uConnect, a population-based cohort study of young Black men who have sex with men (YBMSM) on Chicago's South Side. The sample consists of 618 Black MSM ranging in age from 16 to 29. Cross-sectional measures for this study include Black and gay community closeness, drug use, sexual risk behaviors, HIV testing, and health promotion behaviors. Closeness with the gay community was associated with greater pre-exposure prophylaxis (PrEP) knowledge as well as participating in health promotion programs along with higher rates of transactional sex and having sex under the influence of substances, and increased odds of self-reported HIV seropositivity. Involvement in the Black community was associated with lower odds of reporting being HIV positive. Findings suggest that programs and initiatives are needed to help promote the positive aspects of the Black and gay communities, while minimizing the negative correlates of such involvements. 相似文献
376.
Although the rate of posttraumatic stress disorder (PTSD) among survivors of child maltreatment is high, individuals differ in symptom severity and many do not experience clinically significant levels of psychopathology. The present study tested the indirect effects of child maltreatment severity on adult PTSD, suicidal ideations, and alcohol dependence via anxiety sensitivity. A sample of 336 participants (mean age of 22.81 years, SD = 8.93; 70.2% female) completed an online survey of child abuse and neglect, anxiety sensitivity, PTSD symptom severity, suicidal ideation severity, and alcohol dependence severity. The results revealed significant indirect effects of child maltreatment on PTSD symptom severity through cognitive and social concerns, but not physical concerns. No direct or indirect effects were demonstrated for suicidal ideations or alcohol dependence severity. These findings elucidate mechanisms in the robust relationship between child maltreatment and adult PTSD symptoms and can potentially inform future research on mechanisms of change in psychotherapy. 相似文献
377.
Narissra Maria Punyanunt-Carter Jenna R. Shimkowski Malinda J. Colwell Mary S. Norman 《Journal of divorce & remarriage》2018,59(7):574-589
This study takes an exploratory, qualitative approach to examine college students’ perceptions about divorce in the media. Findings suggest that participants perceived both positive and negative representations of divorced families in the media they consume, highlighting the complex nature of navigating and communicating through a divorce. Specifically, college students reported on aspects of the ex-spousal relationship, how children are affected, and the contrast between life pre- and postdivorce. An inductive theme analysis revealed several positive and negative media representations of divorce. Largely, college students perceive media messages about divorce to be accurate portrayals and impactful representations. 相似文献
378.
Carolette R. Norwood 《International Feminist Journal of Politics》2018,20(1):69-84
ABSTRACTThere is unquestionably a buzz in US Black women’s communities about a trending “natural” phenomenon. Sales of chemical relaxers (sometimes dubbed “creamy crack” among the US Black community) have dropped 34 percent since 2009, while sales of “natural” hair care products that promise to non-chemically enhance or beautify “natural” curls are up exponentially. Corresponding to the rise in sales of “natural” hair care products are beauty blogs, YouTube instructional videos and supportive social groups—such as “natural hair” meet-ups, which have organically emerged for, and been mostly created by, Black women as a tool to support and nurture women as they take this journey. In this article, I use Black feminist P.H. Collins’s work because her understanding of the relationship between knowledge, consciousness and empowerment provides a framework or point of departure for grasping my own lived experience of going “natural” with regards to modes of oppression and methods of resistance. 相似文献
379.
Ríos-Chelén Alejandro Ariel Cuatianquiz-Lima Cecilia Bautista Amando Martínez-Gómez Margarita 《Urban Ecosystems》2018,21(1):15-25
Urban Ecosystems - Vermilion flycatchers, a suboscine, sing songs with more elements in territories with higher urban noise levels. We tested the hypothesis that this pattern is achieved through... 相似文献
380.
Urban Ecosystems - The Andes region is one of the fastest urbanizing regions of the world. The current rate of environmental degradation of streams in this region create an urgent need for... 相似文献