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931.
This study was carried out for the purpose of explaining the mediating effects of a number of psychological variables (strategies for coping with stress, competitiveness, mastery, locus of control, depression and self-esteem) in the relationship between poverty and the well-being of individuals. To carry out the study, a non-probabilistic, stratified sample was used, with the participation of 918 inhabitants of Mexico City from three socioeconomic levels: extremely poor, moderately poor and not poor. A structural model was used for the analysis and treatment of data, and on the basis of that model, it was proven that there are different trajectories (mediations) through which poverty influences subjective well-being. The findings are discussed in light of the literature.  相似文献   
932.
The aim of this investigation is to obtain some baseline self-reported data on the health status and overall quality of life of all residents of the Bella Coola Valley of British Columbia aged 17 years or older, and to measure the impact of a set of designated health determinants on their health and quality of life. In the period from August to November 2001, a variety of procedures were used to ensure that all eligible residents of the Valley received a copy of our questionnaire, and 687 useable questionnaires were obtained for our working dataset. Health status was measured by SF-36 and the U.S. Centers for Disease Control healthy days items. Thirty-one items were used to measure the Provincial Health Officer’s designated determinants of health in four clusters, namely, biological, social and economic, health behaviours and health services determinants. Quality of life was measured by satisfaction levels in 13 specific domains of life (e.g., family, financial security), four global items (e.g., happiness, life satisfaction) and one global Subjective Well-Being Index. Besides obtaining baseline figures on all our measures for the Valley, we made some comparisons among our figures and those from other areas, e.g., Prince George, BC. Most of the measures indicated that the health status and quality of life of Bella Coola Valley residents were lower than those of Prince George residents. For the sample as a whole, SF-36 scores on the eight dimensions ran from 82.3 (physical functioning) to 50.0 (social functioning), with a mean of 62.7. Residents in the Valley averaged 6.5 days in the past 30 in which their health was physically not good, 5.5 days when it was mentally not good and 4.1 days when their health limited their usual daily activities. Eleven percent of respondents described their general health as “excellent” and another 27% said it was “very good”. On a 7-point scale from 1=very dissatisfied to 7=very satisfied, respondents had average life satisfaction and satisfaction with the overall quality of life scores of 5.5. For specific domains of life, the lowest mean level of satisfaction was reported for federal and provincial government officials (3.3) and the highest was reported for living partners and personal safety around home (5.8). Regarding bivariate relations, each of the eight dimensions of SF-36 was significantly correlated with a single item measure of general health, and five of the eight were significantly correlated with the number of good health days. Happiness and the Subjective Well-Being Index were positively but moderately correlated with six of the eight dimensions, and life satisfaction was positively correlated with five. Age was negatively related to general health, but positively related to life satisfaction. Not being of aboriginal descent was positively related to all of the four global health indicators and to the Subjective Well-Being Index. Education was positively related to the four global health measures but not to the three global quality of life measures. The Social Support and Good Family Indexes were positively related to all seven global measures. There was a positive correlation between six of the seven global measures and the frequency with which respondents participated in activities sponsored by voluntary organizations. Frequency of smoking was negatively associated with every global dependent variable except the Physical Health Index. Frequency of skipping meals was negatively associated and average hours of sleep per night was positively associated with all seven global measures. Turning to multivariate relationships, the four clusters of health determinants explained from 12% (SF-36 Mental Health Index) to 24% (general health) of the variance in the dependent global health variables, and from 20% (happiness) to 26% (Subjective Well-Being Index) of the variance in the dependent global quality of life variables. Adding domain satisfaction scores to the total set of predictors allowed us to explain from 20% (SF-36 Mental health Index) to 29% (general health) of the variance in the dependent global health variables, and from 39% (happiness) to 62% (life satisfaction) in the dependent global quality of life variables. By including measures of social support and good family relationships in our set of health determinants, we practically guaranteed that the latter would be relatively strongly predictive of global quality of life.  相似文献   
933.
Summary More than 50% of nests ofRopalidia fasciata were founded by association of foundresses (multifemale nests). The multifemale nests were generally initiated earlier and grew faster than the single-female nests. The survival rate of the multifemale nests was significantly higher than that of single-female nests, and the productivity as measured by the number of cells produced per foundress had a peak at a foundress-group size from 6 to 10. The number of marked foundresses which were seen on their original nest decreased as the colony cycle proceeded, but some of them continued to coexist on the original nests after emergency of many female progeny. Except in the case where a large number of foundresses attended a young nest so that some foundresses could not sit on the nest, the dominance interactions among cofoundresses were mild. More than twothirds (71.4%) of nests (including those at the post-emergence stage) had multiple egg-layers. The foundress association in this species is considered to be beneficial for every foundress because it raises ability to avoid predation or to reconstruct their nests when the nests are destroyed by typhoons. This work was supported in part by a Grant-in-Aid for Special Project Research on Biological Aspect of Optimal Strategy and Social Structure from the Japan Ministry of Education, Science and Culture.  相似文献   
934.
What is the role of population in driving deforestation? This question was put forth as a discussion topic in the cyberseminar hosted by Population Environment Research Network (PERN) in Spring, 2003. Contributors from diverse backgrounds weighed in on the discussion, citing key factors in the population-deforestation nexus and suggesting further courses of action and research. Participants explored themes of their own choosing, with many coming to the forefront. Scale, time, and place-based effects were cited as areas in need of particular attention. Consumption patterns as the mechanism for spurring deforestation were discussed, drawing attention to the differential patterns associated with urban vs. rural demands on forest resources and land. The applicability of the IPAT formula and the influence of its component parts, affluence and technology, when operating in tandem with population, was debated. The relation of demographic factors to these pathways was critically examined. Institutional and governmental influence, such as infrastructure and policies affecting access and incentives, the valuation of resources, and institutional failures such as mismanagement and corruption emerged as a crucial set of factors. This article synthesizes the critical debates in the population-deforestation literature, makes suggestions for future paths of research, and discussed possible policy and direct action initiatives.  相似文献   
935.
Fish living around the coral reefs in the Philippines provide livelihoods for more than a million local fishers and are an important source of protein for coastal communities. However, this rich resource is at risk from myriad threats, which consequently threaten human livelihoods, nutrition, and health. In this paper, we examine the degree to which marine protected areas (MPAs), which aim to conserve marine biodiversity, are associated with improved nutritional outcomes in children under age 5. This analysis, which uses data from the 2008 Philippines Demographic and Health Survey and MPA data from the Coastal Conservation and Education Fund, found a positive association between MPAs and children’s dietary diversity when the MPAs were located closer than 2 km to a child’s community. MPA characteristics such as age or type of management were not consistently associated with dietary diversity. These results suggest a positive association of proximity to MPAs with certain aspects of children’s diet.  相似文献   
936.
Explanations of relationships between migration and environmental change now focus on multiple interactions, risks in destination and immobility. This research applies behavioural migration theory to examine the extent to which immobile populations experiencing environmental degradation exercise agency with respect to location and, in doing so, elucidates what it means to be trapped. This research uses individual survey data from a migrant-sending area in highland Peru where the population experiences negative health and livelihood impacts from climate-related phenomena. Analysis of these data reveals three reasons for non-migration: high levels of satisfaction, resource barriers and low mobility potential. Immobility in dissatisfied people is more likely to be caused by attachment to place than resource constraints. Thus, the results suggest that trapped populations exist along a continuum. This highlights the need for policy responses differentiated by the mobility characteristics and preferences of the individual. Caution, therefore, must be exercised when labelling populations as trapped and promoting relocation.  相似文献   
937.
Research has demonstrated that, in a variety of settings, environmental factors influence migration. Yet much of the existing work examines objective indicators of environmental conditions as opposed to the environmental perceptions of potential migrants. This paper examines migration decision-making and individual perceptions of different types of environmental change (sudden vs. gradual environmental events) with a focus on five developing countries: Vietnam, Cambodia, Uganda, Nicaragua, and Peru. The survey data include both migrants and non-migrants, with the results suggesting that individual perceptions of long-term (gradual) environmental events, such as droughts, lower the likelihood of internal migration. However, sudden-onset events, such as floods, increase movement. These findings substantially improve our understanding of perceptions as related to internal migration and also suggest that a more differentiated perspective is needed on environmental migration as a form of adaptation.  相似文献   
938.
A number of classical as well as quite new utility representations for gains are explored with the aim of understanding the behavioral conditions that are necessary and sufficient for various subfamilies of successively stronger representations to hold. Among the utility representations are: ranked additive, weighted, rank-dependent (which includes cumulative prospect theory as a special case), gains decomposition, subjective expected, and independent increments*, where * denotes something new in this article. Among the key behavioral conditions are: idempotence, general event commutativity*, coalescing, gains decomposition, and component summing*. The structure of relations is sufficiently simple that certain key experiments are able to exclude entire classes of representations. For example, the class of rank-dependent utility models is very likely excluded because of empirical results about the failure of coalescing. Figures 1–3 summarize some of the primary results.JEL Classification  D46, D81  相似文献   
939.
Agents in a large population are randomly matched to play a certain game, payoffs in which represent fitness. Agents may have preferences that are different from fitness. They learn strategies according to their preferences, and evolution changes the preference distribution in the population according to fitness. When agents know the preferences of the opponent in a match, only efficient symmetric strategy profiles of the fitness game can be stable. When agents do not know the preferences of the opponent, only Nash equilibria of the fitness game can be stable. For 2 × 2 symmetric games I characterize preferences that are stable.Jel Codes: C72, A13  相似文献   
940.
A new approach to policy analysis is formulated within the framework of the graph model for conflict resolution. A policy is defined as a plan of action for a decision maker (DM) that specifies the DM’s intended action starting at every possible state in a graph model of a conflict. Given a profile of policies, a Policy Stable State (PSS) is a state that no DM moves away from (according to its policy), and such that no DM would prefer to change its policy given the policies of the other DMs. The profile of policies associated to a PSS is called a Policy Equilibrium. Properties of PSSs are developed, and a refinement is suggested that restricts DMs to policies that are credible in that they are in the DM’s immediate interest. Relationships with existing stability definitions in the graph model for conflict resolution are then explored.  相似文献   
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