Ted Robert Gurr, Rogues, Rebels, and Reformers. A Political History of Urban Crime and Conflict (1977), xii+192 (Sage, Beverly Hills and London, £7.50) 相似文献
We propose a model with two markets to analyze the welfare implications of price discrimination with quality differences. In each market a local firm that operates in that market only competes against a global firm that operates in both markets. Local firms produce higher‐quality goods than the global firm. If the quality levels of the local firms' products are the same, price discrimination is never welfare‐decreasing. If they differ, discrimination is welfare‐increasing if quantity increases. Because of a positive allocation effect of price discrimination, there are parameter values such that welfare increases while total output decreases with price discrimination. (JEL D43, D60) 相似文献
The study analyzed poverty as a function of households’ demographic composition using a longitudinal random sample of 4268 urban and rural households that were followed-up from 2005/6 to 2009/12 in Mexico to estimate short-term changes in living conditions. Well-being was measured as the dwelling unit’s number of rooms, water source, sanitary services, garbage disposal, and fuel. Mobility paths included not poor–not poor, poor–poor, not poor–poor, and poor–not poor. Independent variables included household composition, family characteristics, residential changes, schooling, and occupation. Female headship and older adults negatively impacted poverty, whereas economic dependents may be negatively or positively associated. Fertility incentives for low-income populations are not advisable. Working-age adults contribute only if income-generating opportunities exist locally. 相似文献
Sexual health education for young people is crucial not only for development of norms but also for protection against vulnerabilities during this stage in life. Although several systematic reviews have examined the effectiveness of peer-led sex education, none have focused on the extent of peer participation. The purpose of this review was to evaluate peer-led sexual health education interventions in more developed countries (MDCs). Electronic and manual searches across five social science, education, and medical databases were conducted. Fifteen articles were selected in total. Most (10 of 15) studies gave low or no responsibility to peers. The majority of articles found improvements in sexual health knowledge (13 of 14) and attitudes (11 of 15) at postintervention stages. Two studies showed improved self-efficacy, and three showed behavioral changes. A preliminary synthesis of effectiveness and level of participation was done. Meta-analysis revealed a large effect on knowledge change (Hedges’ g = 0.84, 95% confidence interval [CI]: 0.43 to 1.25) and a medium effect on attitude change (Hedges’ g = 0.49, 95% CI: 0.19 to 0.80). Peer-led interventions could be a powerful tool. This review shows that this approach is effective in changing knowledge and attitudes but not behaviors. Further research and action are needed to understand optimal implementation. 相似文献
This paper argues that an explanation of the role of aesthetic patterning in human action needs to be part of any “qualitative” social theory. It urges the social sciences to move beyond contextualism and to see art as visual, acoustic and other media that lead to heightened sensory perception and the coordination of feelings through symbols. The article surveys the argument that art provides a basic model of how the self learns to interact with external environments; and the complementary thesis that art could be seen as integral to the emergence of systems of human knowledge, communication and economy. Ornamentation and stylization are advanced as two concrete devices through which human attention is captured and experience is ordered through aesthetic patterns. The conclusion is drawn that art offers the social sciences a meaningful account of the perceptual or “qualitative” dimensions of social interactions; and that this is much needed today. 相似文献
In this article, we synthesize Goffman's microsociology with recent developments in fields such as aesthetics, geography, and urban studies labeled “atmosphere theory.” Our central rationale is if microsociology is to deepen its account of embodiment and the noncognitive it needs a theory of spatialized moods. In the second half, we develop our synthesis with respect to musical atmospheres and conclude by drawing on our own research regarding how social actors use music to shape “involvements” and “disinvolvements” in the spatial ambiances of public transportation, the street, the workplace, and the home. 相似文献
Urbanization is a major cause of biodiversity loss and disconnection between people and nature. For this reason, the creation and maintenance of green areas as part of the urban landscape is a common practice in cities around the world. These green areas are generally a result of particular public policies regarding how these areas can be accessed, maintained, and how they are connected to other natural fragments in the city. In an effort to investigate aspects of the ecology of such green areas of the city of Curitiba, southern Brazil, the present study measured distinct parameters of the structure of butterfly assemblages from 19 forest fragments of distinct classes of protection, testing the influence of different policies (protection category) on butterfly assemblages. Comparatively, we also tested the predictive power of landscape variables (at distinct scales) and fragment quality (e.g. diameter at breast height, density of vegetation) using Generalized Linear Models (GLMs). Overall, 14,596 individuals belonging to 412 butterfly species were recorded, but values of species diversity and composition are very heterogeneous, indicating that the protection categories do not significantly interfere with the structure of the butterfly assemblages. More important than the protection category is the forest fragment quality and landscape connectivity. Our models showed that degraded fragments tend to present a specific butterfly composition, whereas the more urbanized landscape have poor butterfly species richness. These results reinforce the importance of implementing public policies that prioritize the conservation of the quality of forest fragments in every class of protection, as well as the conservation of forest fragments throughout the urban landscape.
Urban Ecosystems - Many species of the family Picidae, such as the woodpeckers, excavate the tree-cavities where they nest. Frequently the cavities are used during a single breeding season and... 相似文献
AbstractObjectives: To evaluate whether daytime sleepiness, poor sleep quality, and morningness and eveningness preferences are associated with common mental disorders (CMDs) among college students. Methods: A total of 963 college students completed self-administered questionnaires that collected information about sociodemographic characteristics, sleep quality characteristics, CMDs, and other lifestyle behaviors. Results: The prevalence of CMDs was 24.3% (95% confidence interval [CI] [21.5%, 27.1%]) among all students. Prevalence estimates of both excessive daytime sleepiness and poor sleep quality were higher among females (35.4% and 54.4%) than males (22.0% and 45.8%). Cigarette smoking was statistically significantly and positively associated with having CMDs (p = .034). Excessive daytime sleepiness (odds ratio [OR] = 3.65; 95% CI [2.56, 4.91]) and poor sleep quality (OR = 4.76; 95% CI [3.11, 7.29]) were associated with increased odds of CMDs. Conclusion: Given the adverse health consequences associated with both sleep disorders and CMDs, improving sleep hygiene among college students is imperative to public health. 相似文献