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981.
Social movements are conventionally understood as a means by which groups seek to resolve collective grievances outside of the regular political process. With this in mind, I explore the important role of “institutional activists”– insiders with access to resources and power – who proactively take up causes that overlap with those of grassroots challengers. This article focuses on the history of, and recent developments in, the study of institutional activism, situating the concept within existing social movement theory and providing examples of the varying roles of institutional activists in mobilization.  相似文献   
982.
We find that Union Army veterans of the American Civil War who faced greater wartime stress (as measured by higher battlefield mortality rates) experienced higher mortality rates at older ages, but that men who were from more cohesive companies were statistically significantly less likely to be affected by wartime stress. Our results hold for overall mortality, mortality from ischemic heart disease and stroke, and new diagnoses of arteriosclerosis. Our findings represent one of the first long-run health follow-ups of the interaction between stress and social networks in a human population in which both stress and social networks are arguably exogenous.  相似文献   
983.
This research contributes to an understanding of the relationship between climate change, economic impacts and migration. We model the long-term relationship (up to 45 years of projection) between demographic dynamics—particularly migration—driven by changes in the performance of the economy due to climate changes in the Northeast region of Brazil. The region is of particular relevance to the study of climate change impacts given its large human population (28% of Brazil’s population) and high levels of impoverishment, having an extensive semi-dry area which will be severely impacted by growing temperatures. Ultimately, the integrated model generates state- and municipal-level migration scenarios based on climate change impacts on the primary economic sectors and their articulations with other sectors. Results suggest that the predicted climate changes will impact severely the agriculture sector in the region, acting as a potential migration push factor to other regions in the country. Finally, we discuss how the increased vulnerability of some groups, particularly migrants, can be factored into Brazilian public policy and planning.  相似文献   
984.
Educational attainment is a core social background variable covered in each and every survey of individuals. Since educational institutions and qualifications are difficult to compare across countries, cross-national surveys pose a particular challenge to the measurement of educational attainment. This study performs a comparative construct validation of a number of cross-national measures of education using the European Social Survey. The measures comprise two versions of the International Standard Classification of Education (ISCED), the education scheme developed in the project ‘Comparative Analysis of Social Mobility in Industrial Nations’ (CASMIN) and hypothetical as well as actual years of education. The first ISCED measure corresponds to the well-known main ISCED levels. The second one, the European Survey Version of ISCED (ES-ISCED) developed for this study, represents an effort to reflect different types of education within levels of education by considering ISCED sub-dimensions, most importantly ‘programme orientation’. Using linear regression models, it is shown how much explanatory power educational attainment loses when different cross-national variables are used, as compared to country-specific educational attainment variables (CSEVs), and how these losses vary across measures and countries. The dependent variable used for the construct validation is social status as measured by the International Socio-Economic Index (ISEI). Results suggest that harmonisation always entails some loss of explanatory power for at least a few countries. However, there are clear performance differences between the comparable measures in terms of both the average amount of losses as well as the distribution of losses across countries. The use of actual years of education as well as the levels-only ISCED strongly attenuates the education-social status association on average, but also to very different degrees across countries. CASMIN and ES-ISCED fare considerably better: they show the lowest losses of explanatory power and the lowest variation of losses across countries. Hypothetical years of education lie in between. Some practical implications are then proposed, e.g. on how to implement cross-national measures of educational attainment in international surveys.  相似文献   
985.
Many faculty members consider using case studies but not all end up using them. We provide a brief review of what cases are intended to do and identify three ways in which they can be used. We then use an example to illustrate how we have used the case study method in teaching business demography. Among other benefits, we note that the case studies method not only encourages the acquisition of skills by students, but can be used to promote “deep structure learning,” an approach naturally accommodates other features associated with the case studies method—the development of critical thinking skills, the use of real world problems, the emphasis of concepts over mechanics, writing and presentation skills, active cooperative learning and the “worthwhileness” of a course. As noted by others, we understand the limitations of the case study method. However, given its strengths, we believe it has a place in the instructional toolbox for courses in business demography. The fact that courses we teach is a testament to our perceived efficacy of this tool.  相似文献   
986.
The advent of a continuously updated Master Area File (MAF) following the 2000 census represents an information resource that can be tapped for purposes of developing timely, cost-effective, and precise population estimates for even the smallest of geographical units (e.g., census blocks). We argue that the MAF can be enhanced (EMAF) for these purposes. In support of our argument we describe a set of activities needed to develop EMAF, each of which is well within the current capabilities of the U.S. Census Bureau and discuss various costs and benefits of each. We also describe how EMAF would provide population estimates containing a wide range of demographic (e.g., age, race, and sex) and socio-economic characteristics (e.g., educational attainment, income, and employment). As such, it could largely negate and eliminate the need for many of the traditional demographic methods of population estimation and possibly reduce the number of sample surveys. We identify important challenges that must be surmounted in order to realize EMAF and make suggestions for doing so. We conclude by noting that the idea of the EMAF could be of interest to other countries with MAF files and strong administrative records systems that, like the United States, are facing the challenge of producing good population information in the face of increasing census costs.  相似文献   
987.
988.
There has been a dramatic increase in the number of new HIV diagnoses among people aged 50 to 64 in the United States, and according to the Centers for Disease Control and Prevention (CDC), in just 7 years (by 2015) 50% of those living with AIDS will be aged 50 or older. To address this public health concern, viable HIV/AIDS prevention and treatment options for individuals over the age of 50 are necessary. This article discusses the No One Is Immune initiative that planned, implemented, and coordinated evidence- based HIV/AIDS prevention and education programs specifically tailored for middle-aged and older adults. Guided by the health belief model, an educational conference entitled "Sexuality, Medication, and HIV/AIDS in Middle and Later Adulthood" was conducted along with research activities that assessed HIV/AIDS knowledge gained using both qualitative and quantitative measures. This project can be replicated by other providers within the aging network.  相似文献   
989.
990.
Pollen specialization by solitary bees in an urban landscape   总被引:1,自引:1,他引:0  
Many polylectic bee species are known to specialize locally on one or a few pollen types to increase foraging efficiency. What is relatively unknown is how different landscapes influence foraging decisions, and whether habitat alteration, such as that resulting from urbanization, influences broad-scale foraging activities of bees. This study evaluates the type and diversity of pollen collected by two solitary bees that are common in Toronto, Ontario, Canada, the native Osmia pumila and the exotic O. caerulescens, sampled in trap nests set up in urban parks and gardens. We found that the dominant pollen in every successful brood cell was either of one widespread, cosmopolitan lawn-invasive plant species (Trifolium repens) or one of two wind-pollinated tree genera (Quercus spp. and Betula spp.). In combination, these three represented more than 90 % of all pollen collected by each bee species. Despite considerable overlap in the dominant pollen types collected by each bee species, the exotic O. caerulescens was significantly more specialized than the native O. pumila. Brood cells with Betula as the dominant pollen type were more pollen species-rich than those cells having Trifolium or Quercus as dominant, perhaps a result of the comparatively low protein content in Betula pollen.  相似文献   
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