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511.
Due to economic decline and the recent rise in home foreclosure, many U.S. cities are faced with managing large acreages of vacant land. Interest in local food production on this land has the potential to dramatically reshape the composition of greenspace found within urban landscapes. This study examined how the conversion of vacant land to urban gardens and farms influenced arthropod generalist predator populations and their ability to support biocontrol services. We found that the abundance of Coccinellidae and Syrphidae, and the activity density of Carabidae, Formicidae, and Lycosidae were equivalent among vacant lot and urban garden sites. Dolichopodidae abundance and the activity density of Linyphiidae and Opiliones were reduced in urban gardens whereas Anthocoridae abundance and the activity density of Staphylinidae were greater within urban gardens relative to vacant lots. The biocontrol service supplied by generalist predators was measured using sentinel eggs (Helicoverpa zea (Noctuiidae)) and pupae (Sarcophaga bullata (Sarcophagidae) and Musca domestica (Muscidae)). We found no difference in the biocontrol of H. zea eggs or M. domestica pupae among the focal greenspaces. We found no difference in the removal of S. bullata pupae by predators in June 2010, whereas in August 2010 a greater proportion of pupae were removed in urban garden sites relative to vacant lots. Based on these findings, we discuss the potential of the urban landscape to support generalist predators and sustainable urban gardening and farming.  相似文献   
512.
This paper presents a pen picture about the changes of livelihood patterns to the char people, mostly living under poverty in Bangladesh. The study was conducted on the three Northern Districts such as Nilphamari, Lalmonirhat and Pabna in Bangladesh, where the Char Resources Mobilization project was provided by an international non-government organization—Concern Worldwide Bangladesh. The study used mixed method approach where quantitative data were collected from 378 households (126 from each District) using structured interview schedule. A number of qualitative data collection methods such as focus group discussion, participant observation, community mapping, case study, and key informants interview guidelines were used to collect data about the conditions of the Char people in terms of understanding its connection with their livelihoods and socio-economic consequences. This study compares the changes with influential factors with a baseline survey conducted in 2007. Findings showed that there were a number of areas such as education, income, family assets and properties, annual household income, employment, savings, improving market chain, food intake and food security, presence of governmental and non-governmental organizations’ services and awareness about disaster and vulnerability and coping strategies were found positive. The study also observed some negative changes on assets base and livelihood options. The paper argues that the findings on these changes will help to formulate policy on poverty alleviation for the government and non-government authorities who implement the similar type of programmes.  相似文献   
513.
Sociologists continue to observe the ways race permeates America's social institutions, the institution of sport being no exception. Although researchers have explored customer racial discrimination via examinations of the secondary sports card market, only three studies have explored the phenomenon in the context of basketball, a sporting context with a higher proportion of non-White players than the baseball and football leagues that have been the primary focus to date. We explore the unique way race matters on the hardwood by employing a methodological approach that previously has been used to study card collecting in other contexts. Data were obtained for 215 retired players and their rookie cards. Controlling for other factors, to include career performance, position, and card scarcity, the results reveal no direct effect of race on card values, but there is an interaction effect between race and Hall of Fame status that impacts card prices. The potential source and implications of this interaction are discussed as well as suggestions for future research.  相似文献   
514.
This study seeks to extend the body of knowledge of pro-social behavior in comparative market settings by reporting on a high-stakes ultimatum game and revelation game experiments in two transition economies: Kazakhstan and Uzbekistan. While controlling for cultural differences and framing effects, we find statistically significant differences in fairness and honesty behavior between the two countries. Specifically, subjects in Uzbekistan (in an earlier stage of transition to a market economy) are fairer and more honest than their later-stage Kazakh counterparts. Our experimental findings have implications for the literature on pro-social behavior and market economies, and more generally, on the transmission process between formal and informal institutions.  相似文献   
515.
We introduce and study general mathematical properties of a new generator of continuous distributions with one extra parameter called the generalized odd half-Cauchy family. We present some special models and investigate the asymptotics and shapes. The new density function can be expressed as a linear mixture of exponentiated densities based on the same baseline distribution. We derive a power series for the quantile function. We discuss the estimation of the model parameters by maximum likelihood and prove empirically the flexibility of the new family by means of two real data sets.  相似文献   
516.
Employing data from the Household, Income and Labour Dynamics in Australia survey, this paper examines the level, determinants and distribution of self-reported life satisfaction, as well as the prevalence and severity of dissatisfaction in Australia over the period 2001–2010. Against most objective measures Australia’s economic performance during this period was exemplary. Yet our results indicate a steady decline in life satisfaction from 2003 onwards, as well as a diminishing gap between the life satisfaction of males and females. Results also suggest that inequality in life satisfaction has generally declined. Geographic heterogeneity in the distribution of life satisfaction is apparent, and a number of socio-economic and demographic factors are found to serve an important role in determining an individual’s level of life satisfaction. Measures of the extent of dissatisfaction reveal an encouraging downward trend and provide policy makers with an alternative perspective from which to assess societal welfare.  相似文献   
517.
518.
Mexican workplaces have changed significantly in response to the global marketplace by restructuring, downsizing, and implementing new production and administrative processes. This case study analyzes organizational commitment at a Mexican‐owned multinational corporation within the context of workplace transformation. Based on in‐depth interviews with 83 women and men, I identify two sources of commitment—family‐friendly and career‐friendly employment practices. Using the framework of the gendered life course, I show commitment fluctuated given the employees' stage in the life course. This study builds on the gender and work research by exploring how individual attributes of gender and parental status contribute to organizational commitment, but are underscored by the complexity of workplace context.  相似文献   
519.
The role of information processing in understanding people's responses to risk information has recently received substantial attention. One limitation of this research concerns the unavailability of a validated questionnaire of information processing. This article presents two studies in which we describe the development and validation of the Information‐Processing Questionnaire to meet that need. Study 1 describes the development and initial validation of the questionnaire. Participants were randomized to either a systematic processing or a heuristic processing condition after which they completed a manipulation check and the initial 15‐item questionnaire and again two weeks later. The questionnaire was subjected to factor reliability and validity analyses on both measurement times for purposes of cross‐validation of the results. A two‐factor solution was observed representing a systematic processing and a heuristic processing subscale. The resulting scale showed good reliability and validity, with the systematic condition scoring significantly higher on the systematic subscale and the heuristic processing condition significantly higher on the heuristic subscale. Study 2 sought to further validate the questionnaire in a field study. Results of the second study corresponded with those of Study 1 and provided further evidence of the validity of the Information‐Processing Questionnaire. The availability of this information‐processing scale will be a valuable asset for future research and may provide researchers with new research opportunities.  相似文献   
520.
In 1996, Congress overhauled welfare policy to promote marriage and work as ways to lift American families out of poverty. Almost all of the funding for governmental marriage promotion has been devoted to relationship skills programs intended to help couples strengthen their relationships, encourage them to marry, and thereby prevent poverty. Marriage promotion policy has sparked intense debate, especially over the connection between marriage and family inequality. While advocates of the policy argue the government should promote marriage because it fosters social and economic well‐being, critics challenge the assumption that marriage itself causes these benefits or will help lift poor families out of poverty. Recent sociological research on why poor and low‐income couples marry less finds that they tend not to marry if they cannot meet a specific economic threshold. This suggests that rather than promoting the view that relationship skills en route to marriage can help prevent poverty, marriage promotion policy could likely better serve disadvantaged families by acknowledging and addressing the socioeconomic roots of family inequality.  相似文献   
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