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381.
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
382.
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
383.
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
384.
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
385.
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
386.
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
387.
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
388.
389.
Keva M. Miller J. Mark Eddy Sharon Borja Sarah R. Lazzari 《Smith College studies in social work》2017,87(1):59-77
ABSTRACTIncarcerated parents have complex life histories that often remain unresolved during incarceration, can continue to create barriers to prosocial success on release, and present similar intergenerational challenges for their children. This study examines the life histories of incarcerated fathers and mothers from the Pacific Northwest and how their experiences vary based on race and ethnicity. Five areas examined were exposure to trauma, child welfare involvement, mental health and substance abuse problems, juvenile justice and adult criminal justice involvement, and intergenerational criminal justice involvement. The sample comprised 359 incarcerated parents, and their racial/ethnic composition was 59% White, 14% African American, 11% multiracial, 8% Native American, and 7% Latino. Few differences were found across racial and ethnic groups. Mothers appeared more similar to each other across groups than fathers. Results illustrated similarities yet some surprising differences with national trends on key study variables. Implications for future research and intervention and prevention are discussed. 相似文献
390.
Linear mixed models have been widely used to analyze repeated measures data which arise in many studies. In most applications, it is assumed that both the random effects and the within-subjects errors are normally distributed. This can be extremely restrictive, obscuring important features of within-and among-subject variations. Here, quantile regression in the Bayesian framework for the linear mixed models is described to carry out the robust inferences. We also relax the normality assumption for the random effects by using a multivariate skew-normal distribution, which includes the normal ones as a special case and provides robust estimation in the linear mixed models. For posterior inference, we propose a Gibbs sampling algorithm based on a mixture representation of the asymmetric Laplace distribution and multivariate skew-normal distribution. The procedures are demonstrated by both simulated and real data examples. 相似文献