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411.
Species that successfully inhabit urban ecosystems are rare, and urbanisation often drives localised extinctions of native species. Nonetheless, some species take advantage of the novel conditions available in cities and increase in abundance. Trends in the abundance and distribution of species in urban areas have received much attention, but the precise elements of urban ecosystems that affect the survival of urban-dwelling species are largely unknown. Animals that successfully exploit urban environments may do so because of increases in the availability of resources or habitats. Here we assess the effects of anthropogenic landscapes and prey abundance on the persistence of an orb-weaving spider, Nephila plumipes. We assessed spider persistence for six months in situ along an urban gradient in Sydney. We then transplanted spiders from a common garden into sites along the gradient, monitored their persistence in the new environment and measured a suite of environmental variables at local and landscape scales. The abundance of prey was closely linked with spider persistence, in both the survey and the transplant experiment, and was positively associated with anthropogenic habitats. The surveyed spiders survived longer when located closer to the coast and transplanted spiders persisted longer in smaller sites with more impervious surfaces and reduced vegetation cover. Our study shows that urbanisation has a strong effect on potential prey abundance and can lead to increased persistence of N. plumipes, demonstrating the broad impacts that habitat disturbance can have on the life history and trophic interactions of city-dwelling animals. 相似文献
412.
Sarah Bartos Smith Jenny E. McKay Jennifer K. Richardson Amy A. Shipley Michael T. Murphy 《Urban Ecosystems》2016,19(2):577-598
Urbanization poses threats to earth’s biota, and retention of remnant native habitat in protected areas within expanding urban boundaries may help alleviate threats to wildlife. However, it is unclear for nearly all nonsynanthropic (i.e., not benefiting from an association with humans) species whether vital rates in urban habitats can sustain populations or if populations persist only through immigration from outside the urban boundary. We conducted a three-year study of spotted towhees (Aves: Pipilo maculatus) breeding in four undeveloped parks in Portland, OR, USA, to measure park-specific seasonal reproductive output (F) and annual adult survival (SA). We developed a stochastic model that combined F and SA with an estimate of first-year survival to measure population growth rate (λ) in all parks assumed to be closed to immigration. F differed among parks but SA did not. Relatively high F was possible because many pairs raised >1 brood/season. When combined with empirical estimates of survival through the 30-day period of post-fledging parental care (SD = 0.645), only 2 of 4 parks were self-sustaining (i.e., λ > 1.0). However, SD reflected substantial loss of fledglings to domestic cats (Felis catus). Assuming no loss to cats and either partial compensatory or additive mortality of fledglings substantially improved prospects of population persistence for declining (sink) populations. Moreover, allowing low levels of immigration to sinks reversed population declines in most parks even when vital rates were insufficient to maintain populations. Our results suggest that nonsynanthropic bird species can persist in urban landscapes, but also that offspring mortality in the post-fledging period may be a critical determinant of population viability. 相似文献
413.
Richard J. E. James Claire O’Malley Richard J. Tunney 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2016,32(4):1155-1173
Analyses of disordered gambling assessment data have indicated that commonly used screens appear to measure latent categories. This stands in contrast to the oft-held assumption that problem gambling is at the extreme of a continuum. To explore this further, we report a series of latent class analyses of a number of prevalent problem gambling assessments (PGSI, SOGS, DSM-IV Pathological Gambling based assessments) in nationally representative British surveys between 1999 and 2012, analysing data from nearly fifty thousand individuals. The analyses converged on a three class model in which the classes differed by problem gambling severity. This identified an initial class of gamblers showing minimal problems, a additional class predominantly endorsing indicators of preoccupation and loss chasing, and a third endorsing a range of disordered gambling criteria. However, there was considerable evidence to suggest that classes of intermediate and high severity disordered gamblers differed systematically in their responses to items related to loss of control, and not simply on the most ‘difficult’ items. It appeared that these differences were similar between assessments. An important exception to this was one set of DSM-IV criteria based analyses using a specific cutoff, which was also used in an analysis that identified an increase in UK problem gambling prevalence between 2007 and 2010. The results suggest that disordered gambling has a mixed latent structure, and that present assessments of problem gambling appear to converge on a broadly similar construct. 相似文献
414.
Alice E. Donlan Jen Elise Prescott Jonathan F. Zaff 《Journal of Children and Poverty》2016,22(2):113-132
We present an analysis of the contexts within which adolescents graduate from high school and enroll in college. Data from the National Longitudinal Study of Adolescent Health show that adolescents’ school engagement, maternal academic monitoring, and community poverty significantly interact to explain differences in high school graduation and college enrollment rates (n?=?7100). To examine this association, we performed weighted logistic regression analyses, controlling for gender, race, block level unemployment, and block level median income. Findings suggest that protective factors can help youth overcome the challenges associated with community poverty and achieve academically in low and medium levels of poverty, but that youth in high-poverty contexts may need more resources to reach higher levels of academic attainment. 相似文献
415.
Research highlights lasting cognitive and academic challenges in youth internationally adopted from institutional care. However, there is a lack of research examining internationally adopted students' sense of membership at school and associated academic and psychological outcomes. The current study measured sense of school membership and academic and psychological outcomes in post-institutionalized internationally adopted high school students (n = 29) compared to adolescents internationally adopted from foster care (n = 28) and non-adopted adolescents (n = 32). Post-institutionalized males had a lower sense of school membership than males adopted from foster care or non-adopted males. Group differences in school membership were mediated by academic achievement and psychological well-being. 相似文献
416.
Moral panics are central to social work policy and practice. Voluntary agencies and statutory bodies (including governments) create and sustain moral panics in order to raise awareness of, and win support for, their own understandings of social issues and problems. This is not a neutral enterprise; on the contrary, moral panics often have consequences that are negative, whether intended or unintended. Far from leading to greater social justice and a more equal society, they may reinforce stereotypes and lead to fearful, risk-averse practice. This paper discusses one such moral panic in 2013 that centred on the story of ‘Maria’, a Bulgarian Roma child living in Greece. The paper explores the meaning and use of the concept of moral panic before unpacking this case-study example in more detail. We argue that the moral panic over ‘Maria’ has much to tell us about ideas of welfare and protection, institutional racism and children and childhood, as well as the connections between ‘private troubles’ and ‘public issues’. We conclude that social work as a profession must stand up to complexity, and in doing so, be aware of its own role in relation to moral panics. 相似文献
417.
Ramón E. López Eugenio Figueroa B. Pablo Gutiérrez C. 《Journal of Economic Inequality》2016,14(4):379-394
Most previous studies of income inequality have either ignored capital gains or have used taxable realized capital gains to estimate top incomes. Neither of these approaches is fully satisfactory. We apply for the first time a new methodology that allows us to account for fundamental accrued capital gains as part of the top incomes in a theoretically consistent manner. We estimate the shares of the super-rich in Chile showing that accrued capital gains have a large impact on these estimates. Also, the top income shares estimated using fundamental capital gains appear to exhibit a more stable and presumably more plausible time profile than estimates based on capital gains derived from asset market variations. 相似文献
418.
Mehmet E. Yaya 《Review of Economics of the Household》2016,14(3):695-714
Until recently, in works of literature, the assimilation of immigrants had been viewed as an individualistic rather than a community-based process. However, Hatton and Leigh (2011) showed that immigrants integrate to their host country as communities, not as individuals; hence, group characteristics play as much of a role as individual characteristics in terms of adaptation. This paper introduces another dimension to the immigrant adaptation proxies that reflect community-based characteristics. The fundamental assertion of this paper is that inequality can be used as a proxy of adaptation within immigrant groups. Immigrant groups that exhibit income and education distributions similar to those of the natives can be regarded as well-adapted groups, while those who exhibit vastly different distributions should be considered to be groups with limited adaptation. Using the American Community Survey (ACS) 2010 cohort, this paper presents the initial findings of the within-group inequality of immigrants. Then, a cross-sectional regression analysis is employed to analyze the determinants of inequality across these immigrant groups. The results suggest that immigrant community-based characteristics, such as average income, education, and number of years that the immigrants have spent in the US, can indeed explain most of the variation in inequality. 相似文献
419.
Mary E. Byrnes 《Sociology Compass》2016,10(10):906-917
This article reviews current theories of age and place to demonstrate a more inclusive perspective in sociology that considers race, age, and place. Scholars who study age have advanced our knowledge about what place means to old people or how environment operates in an oppressive way to aged bodies. Likewise, race scholars have advanced our knowledge about the ways oppression and White supremacy are rooted in place. Yet the two bodies of literature do not inform one another, and there are potentially dangerous gaps in our knowledge that contribute to oppression. The result is age scholarship about environment that lacks a critical race perspective and race scholarship on place that ignores the oppressive conditions of age. By reviewing these pieces, I argue that scholars must inform themselves of the ways in which we overlook important analyses and may potentially contribute to our own ageism. 相似文献
420.
MATT E. RYAN 《Economic inquiry》2014,52(1):138-154
Previous research has isolated the effect of “congressional dominance” in explaining bureaucracy‐related outcomes. This analysis extends the concept of congressional dominance to the allocation of H1N1, or swine flu, vaccine doses. States with Democratic United States Representatives on the relevant House oversight committee received roughly 60,000 additional doses per legislator during the initial allocation period, though this political advantage dissipated after the first 3 weeks of vaccine distribution. As a result political factors played a role in determining vaccine allocation only when the vaccine was in particularly short supply. At‐risk groups identified by the Centers for Disease Control (CDC), such as younger age groups and first responders, do not receive more vaccine doses, and in fact receive slightly fewer units of vaccine. (JEL D72, D73, I18) 相似文献