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161.
Understanding contemporary urban landscapes requires multiple sets of spatially and temporally compatible data that can integrate historical land use patterns and disturbances to land cover. This paper presents three principal methods: (1) core analysis; (2) historic mapping; and (3) gradient analysis, to link spatial and temporal data for urban ecosystems and applies their use in the Baltimore-Chesapeake region. Paleoecological evidence derived from the geochronology of sediment cores provides data on long-term as well as recent changes in vegetative land cover. This information, combined with contemporary vegetation maps, provides a baseline for conducting trend analyses to evaluate urbanization of the landscape. A 200-year historical land use database created from historical maps, census data, and remotely sensed data provides a spatial framework for investigating human impacts on the region. A geographic information system (GIS) integrates core analyses with historic data on land use change to yield a comprehensive land use and land cover framework and rates of change. These data resources establish the regional foundation for investigating the ecological components of an urban ecosystem. Urban-rural gradient analyses and patch analyses are proposed as the most appropriate methods for studying the urban ecosystem as they link ecological and social patterns and processes for varying degrees of urbanization. 相似文献
162.
Using data from Finland, this paper contributes to a small but growing body of research regarding adult children's education, occupation, and income and their parents' mortality at ages 50+ in 1970–2007. Higher levels of children's education are associated with 30–36 per cent lower parental mortality at ages 50–75, controlling for parents' education, occupation, and income. This association is fully mediated by children's occupation and income, except for cancer mortality. Having at least one child educated in healthcare is associated with 11–16 per cent lower all-cause mortality at ages 50–75, an association that is largely driven by mortality from cardiovascular diseases. Children's higher white-collar occupation and higher income is associated with 39–46 per cent lower mortality in the fully adjusted models. At ages 75+, these associations are much smaller overall and children's schooling remains more strongly associated with mortality than children's occupation or income. 相似文献
163.
Gülay Türkmen 《Qualitative sociology》2018,41(4):569-591
This article is an inquiry into understanding why supranational religious identity often fails to act as a conflict resolution tool in religiously homogenous ethnic conflicts. Narrowing its focus down to the role of religious elites as potential peacemakers in such conflict zones, it proposes the divergence in their conceptualizations of religious and ethnic identities as an explanatory factor. Building on 62 in-depth interviews conducted in Turkey with Sunni Muslim Kurdish and Turkish religious elites, it identifies a three-fold typology of religious and ethnic identities, as conceptualized by these elites: 1) religio-ethnic; 2) ethno-religious; 3) religious. After exemplifying each category with interview data it demonstrates the role these distinctions play in preventing the successful implementation of “Muslim fraternity” as a solution to the Kurdish conflict in Turkey. With these findings, the article contributes to both the literature on religion in conflict resolution and that on identity formation and boundary making. While it invites the former to turn its gaze from macro-level structural factors to meso- and micro-level cultural factors in analyzing religious elite involvement in conflict resolution, it invites the latter to stop employing “ethnicity” as an all-encompassing term (that covers a vast array of identity markers including religion) and focus, instead, on the gradations between religion and ethnicity as sources of identity. 相似文献
164.
Christopher T. Belser Diandra J. Prescod Andrew P. Daire Melissa A. Dagley Cynthia Y. Young 《The Career development quarterly》2018,66(2):176-181
Undergraduate career planning courses have shown efficacy in decreasing students’ negative career thoughts; however, universities have minimally applied these courses to science, technology, engineering, and math (STEM) populations. This study compared the influence of a STEM‐focused career planning course for undecided STEM students with a seminar course for decided STEM majors. An analysis of covariance with covariate adjustment revealed that undecided career planning students had lower adjusted mean scores on a measure of negative career thinking than the decided STEM majors after the first semester of college. The results provide support for the efficacy of STEM‐focused career planning courses and measuring negative career thoughts with STEM undergraduates. 相似文献
165.
Julian P. T. Higgins Simon G. Thompson David J. Spiegelhalter 《Journal of the Royal Statistical Society. Series A, (Statistics in Society)》2009,172(1):137-159
Summary. Meta-analysis in the presence of unexplained heterogeneity is frequently undertaken by using a random-effects model, in which the effects underlying different studies are assumed to be drawn from a normal distribution. Here we discuss the justification and interpretation of such models, by addressing in turn the aims of estimation, prediction and hypothesis testing. A particular issue that we consider is the distinction between inference on the mean of the random-effects distribution and inference on the whole distribution. We suggest that random-effects meta-analyses as currently conducted often fail to provide the key results, and we investigate the extent to which distribution-free, classical and Bayesian approaches can provide satisfactory methods. We conclude that the Bayesian approach has the advantage of naturally allowing for full uncertainty, especially for prediction. However, it is not without problems, including computational intensity and sensitivity to a priori judgements. We propose a simple prediction interval for classical meta-analysis and offer extensions to standard practice of Bayesian meta-analysis, making use of an example of studies of 'set shifting' ability in people with eating disorders. 相似文献
166.
The goals of the research were to explore African-American practitioners’ satisfaction with public relations as a career and to examine their perceptions of tokenism and pigeonholing in the workplace. Three key themes emerged from the research: career entry and social support in public relations; encounters with everyday racism; and pigeonholing in public relations. For the majority of 12 African-American practitioners interviewed, they have experienced discrimination in their careers and in public relations, yet the practitioners did not see themselves as pigeonholed in their roles or positions. The complete study can be requested from the author. 相似文献
167.
Martine T.E. Puts Nastaran Shekary Guy Widdershoven Jeannette Heldens Dorly J.H. Deeg 《Journal of Aging Studies》2009,23(4):258-266
Frailty is a term often used by researchers and clinicians to describe a state in which older persons are at risk for adverse outcomes such as falls, disability, institutionalization and mortality. However, no study so far examined what frailty means to older persons. Therefore the aim of this study was to describe the meaning that older community-dwelling persons attach to frailty. Twenty-five semi-structured interviews were conducted. The interviews were analyzed using the grounded theory method. Frailty was described as being in poor health, having walking difficulties, feeling down, being anxious, having few social contacts and not being able to do the things one likes to do. Men described in more detail the physical dimension whereas women elaborated in more depth on the psychological and social component. Existing definitions of frailty should be adjusted to better reflect the meaning of frailty for older persons. 相似文献
168.
This study reports a meta-analysis of 75 estimates of the efficiency-wage effect. It reveals a strong efficiency-wage effect
that depends upon whether researchers control for potential simultaneity between wages and productivity. Studies that control
for simultaneity tend to report stronger effects. Clear evidence of publication selection is also found. E24, J30.
相似文献
T. D. Stanley (Corresponding author)Email: |
169.
Our understanding of the underlying demographic components of population change in new Hispanic destinations is limited. In this paper, we (1) compare Hispanic migration patterns in traditional settlement areas with new growth in emerging Hispanic destinations; (2) examine the role of immigration vis‐à‐vis domestic migration in spurring Hispanic population redistribution; and (3) document patterns of migrant selectivity, distinguishing between in‐migrants and non‐migrant Hispanics at both the origin and destination. We use several recent datasets, including the 1990 and 2000 Public Use Microdata Samples (which include new regional geocodes), and the 2005 and 2006 files of the American Community Survey. Our results document the widespread dispersion of the Hispanic population over the 1990–2006 period from established Hispanic gateways into new Hispanic areas and other parts of the country. Nearly one‐half of Hispanic net migration in new destinations comes from domestic gains. In contrast, both established and other Hispanic areas depend entirely on immigration, with each losing domestic migrants to high growth areas. Migrant flows also are highly differentiated by education, citizenship, and nativity. To fully understand the spatial diffusion of Hispanics requires a new appreciation of the complex interplay among immigration, internal domestic migration, and fertility. 相似文献
170.
Kevin A. Whitehead Andrew T. Ainsworth Michele A. Wittig Brandy Gadino 《Journal of research on adolescence》2009,19(1):123-135
The present paper develops and tests two temporal models of the relationships among adolescents' ethnic identity exploration, ethnic identity affirmation and belonging, and attitudes toward their racial/ethnic ingroup and outgroups. Structural equation models for Euro‐Americans, Asian Americans, and Latinos revealed that all hypothesized relationships were positive and significant. The model in which ethnic identity exploration (at Time 1) predicts ethnic identity affirmation and belonging (at Time 2) was superior to the alternative model in which the relationship between them was reversed (i.e., affirmation and belonging at Time 1 predicts exploration at Time 2). Results (1) support the importance of exploration as a basis for establishing a secure attachment to one's ethnic identity, which, in turn, has positive implications for attitudes toward one's own group and other groups and (2) suggest that maintenance of ethnic identity is compatible with positive attitudes toward ethnic outgroups. 相似文献