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991.
Under many circumstances, the global rural-to-urban migration trend may be increasingly adopted as a short-term coping strategy to shifting ecologies and natural disasters. While offering certain benefits from macro-level economic and public health perspectives, these migrations may also have unintended psychological consequences that are not easily understood through traditional disaster studies or cost–benefit analyses. If the goal of disaster and climate change research is to promote successful adaptation, then the long-term psychological well-being of people who have survived disaster and either adapted in situ or migrated into urban environments, is paramount. This article integrates research on disasters and climate change-induced migration with emerging perspectives from environmental psychology and the psychology of natural disasters to consider the potential costs of particular migration scenarios. We apply this analysis to the case of Shishmaref, Alaska, a rural Iñupiat community on the northwest coast of Alaska facing habitual flooding disasters linked to climate change. Findings from Shishmaref illustrate the cultural vitality of subsistence landscapes and the potential health risks of compromised human–ecological relationships due to migration and/or displacement. Recommendations for policy makers and researchers are offered for promoting long-term well-being among affected individuals and communities. 相似文献
992.
Raphael J. Nawrotzki Allison M. Schlak Tracy A. Kugler 《Population and environment》2016,38(2):164-184
Studies investigating the connection between environmental factors and migration are difficult to execute because they require the integration of microdata and spatial information. In this article, we introduce the novel, publically available data extraction system Terra Populus (TerraPop), which was designed to facilitate population–environment studies. We showcase the use of TerraPop by exploring variations in the climate–migration association in Burkina Faso and Senegal based on differences in the local food security context. Food security was approximated using anthropometric indicators of child stunting and wasting derived from Demographic and Health Surveys and linked to the TerraPop extract of climate and migration information. We find that an increase in heat waves was associated with a decrease in international migration from Burkina Faso, while excessive precipitation increased international moves from Senegal. Significant interactions reveal that the adverse effects of heat waves and droughts are strongly amplified in highly food insecure Senegalese departments. 相似文献
993.
994.
Susan L. Brown Wendy D. Manning Krista K. Payne 《Population research and policy review》2016,35(1):1-21
Research on family structure and child well-being rarely includes children in same-sex parent families, a notable omission since 28 % of female–female couple households contain children. Using the 2010–2013 pooled current population survey (CPS), we examined children’s economic well-being by family structure. These data were ideal for this study because they included a sizeable number of children in same-sex cohabiting mother families and the CPS measured both official and supplemental poverty, incorporating the cohabiting partner. Using the official poverty measure, children in same-sex cohabiting mother families were more likely to be poor than their counterparts in either different-sex cohabiting or married parent families. Using the supplemental poverty measure, children in same-sex mother families were no more likely to be poor than children in all other types of different-sex two-parent families. 相似文献
995.
The study examines cointegration and causal relationship between FDI, terrorism and economic growth in Pakistan using quarterly frequencies for the period 1988–2010. For empirical analysis data is divided into two sub-periods i.e. pre 9/11 (1988–2001) and post 9/11 (2002–2010) periods. The results show that long run cointegration holds between FDI, terrorism and economic growth. Granger causality results indicate that there is bidirectional short and long run causality between economic growth and FDI for both sub-samples. These findings are supported by variance decomposition and impulse response analysis. The findings suggest applicability of modernization theory to explain FDI and economic growth relationship. The results also reveal that terrorism has a deteriorating impact on FDI. 相似文献
996.
Lucia C. Lykke 《Feminist Media Studies》2016,16(2):239-260
Prior research on media representations of race, gender, and sexual violence has established that media emphasize women’s role in preventing their own victimization and omit Black women as victims. This study uses feminist intersectionality to build on prior research by investigating not only how social groups are portrayed, but whether and how the intended audience matters for media representations. Specifically, who are the portrayed victims of sexual violence, and how is fear of sexual violence communicated to different audiences? Content analysis of articles in race- and gender-specific magazines shows two key mechanisms of representation through which racism and sexism work together: visibility and denial. Results show that White women are hypervisible as victims while Black women as victims are relatively invisible compared to Black men’s persecution and Black children’s victimization; men’s magazines deny the importance of sexual violence as a problem, focusing on false accusations and convictions. These narratives go largely unchallenged regardless of the source’s intended audience, demonstrating that portrayals of sexual violence are both gendered and racialized across multiple media sources. 相似文献
997.
Unfortunately many of the numerous algorithms for computing the comulative distribution function (cdf) and noncentrality parameter
of the noncentral F and beta distributions can produce completely incorrect results as demonstrated in the paper by examples. Existing algorithms
are scrutinized and those parts that involve numerical difficulties are identified. As a result, a pseudo code is presented
in which all the known numerical problems are resolved. This pseudo code can be easily implemented in programming language
C or FORTRAN without understanding the complicated mathematical background.
Symbolic evaluation of a finite and closed formula is proposed to compute exact cdf values. This approach makes it possible
to check quickly and reliably the values returned by professional statistical packages over an extraordinarily wide parameter
range without any programming knowledge.
This research was motivated by the fact that a very useful table for calculating the size of detectable effects for ANOVA
tables contains suspect values in the region of large noncentrality parameter values compared to the values obtained by Patnaik’s
2-moment central-F approximation. The cause is identified and the corrected form of the table for ANOVA purposes is given. The accuracy of the
approximations to the noncentral-F distribution is also discussed.
The authors wish to thank Mr. Richárd Király for his preliminary work. The authors are grateful to the Editor and Associate
Editor of STCO and the unknown reviewers for their helpful suggestions. 相似文献
998.
C.C. Heyde 《Journal of statistical planning and inference》1996,50(3):373-378
This paper illustrates the use of quasi-likelihood methods of inference for hidden Markov random fields. These are simple to use and can be employed under circumstances where only the model form and its covariance structure are specified. In particular they can be used to derive the same estimating equations as the E-M algorithm or change of measure methods, which make full distributional assumptions. 相似文献
999.
Growing human populations make it imperative for ecologists to identify strategies to conserve biodiversity in human-dominated landscapes, such as cities. Effects of urbanization on birds are particularly well-studied, but questions remain regarding the best conservation approaches. Debate about the relative utility of focusing conservation efforts on nature reserves versus developed lands has focused largely on comparing species abundance or presence, with few studies addressing underlying behavioral or demographic mechanisms. Here we evaluated differences in avian reproductive success in nature reserves and matrix habitats to test the assumption that nest predation is lower within areas protected from development. Specifically, we investigated 1) whether nest survival differed in replicated pairs of forest parks and residential neighborhoods and 2) whether differences in nest survival were associated with changes in which species most frequently depredated nests. From April–August 2007–2014, we monitored nests of two native birds, American robin (Turdus migratorius) and northern cardinal (Cardinalis cardinalis), and video-documented nest predators in paired forest-matrix habitats in the Columbus, Ohio metropolitan area. We found similar rates of nest survival in the two habitats for both robins (Χ21?=?0.715, p?=?0.398, n?=?741 nests) and cardinals (Χ21?=?0.926, p?=?0.336, n?=?1156 nests), but interactions between predators and prey differed. In particular, domestic cats (Felis catus) were over five times as likely to depredate cardinal nests in matrix habitats versus forest parks (Χ21?=?7.24, simulated p?=?0.010; nforest?=?3, nmatrix?=?7). Our results suggest that at least in some circumstances, nest success of native birds may be equivalent between nature reserves and adjacent residential matrix habitats, and thus residential neighborhoods may contribute positively to bird conservation in urban landscapes. 相似文献
1000.
Sabine S. Nooten Patrick Schultheiss Jules Wright Catriona Macdonald Brajesh K. Singh James M. Cook Sally A. Power 《Urban Ecosystems》2018,21(3):565-576
Recent concern over increasing loss of biodiversity has prompted considerable interest in the role of urban green spaces as reservoirs of local biodiversity. This study assessed the diversity of three indicator taxa - plants, ants and birds - on golf courses spanning a wide range of environmental variation in terms of climate, elevation, course age, size and connectivity to native woodland. Species richness and community composition was further compared between contrasting on-course habitat types that reflect different management intensities. We identified a set of taxon-specific environmental correlates indicating an intricate interplay of landscape- and local-scale variables that affect local species diversity. Our results show that floristic diversity is positively associated with the amount of rainfall, whereas ant and bird diversity are related to local-scale factors, particularly the number of trees and the size of water features on a site. The amount of on-course native habitat was a strong predictor of plant and ant diversity and was also associated with the number of unique species at the site level; this reinforces the value of remnant habitat patches as local biodiversity reservoirs that represent mini hot-spots in an otherwise species-poor urban landscape. Community composition for all three taxa differed markedly between non-playing and playing areas, with boundary and remnant habitats generally having more diverse, species-rich communities. Our results suggest that local floral and faunal biodiversity on urban golf courses can be enhanced by creating woody non-playing areas and, especially, by preserving, restoring or expanding remnant habitats. 相似文献