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661.
Urban ecosystems are characterized by “urban exploiters”: species that thrive in the modified environment of cities. Few insects have been categorized as such, in part because they are usually considered as pests first, in part because many studies do not identify to species, and in part because many insects can survive in small vegetated areas within the urban matrix. Some termites may be prime examples of urban exploiters; Coptotermes species are rare in natural forests, but are abundant and major pests in urban areas. We investigated the genetic structure of the South East Asian species Coptotermes gestroi in the urban nation of Singapore. There was a panmictic population across the city, yet all 29 colonies were genetically distinct, and many had expanded from recent bottlenecks. There were no significant differences between colonies in vegetated areas (forests and parks), and those in urban habitats. The genetic pattern is similar to some other urban exploiter species in comparable environments, thus confirming C. gestroi is a native species that has become an urban exploiter, the first termite to be considered as such.  相似文献   
662.
Children growing up in homes with many books get 3 years more schooling than children from bookless homes, independent of their parents’ education, occupation, and class. This is as great an advantage as having university educated rather than unschooled parents, and twice the advantage of having a professional rather than an unskilled father. It holds equally in rich nations and in poor; in the past and in the present; under Communism, capitalism, and Apartheid; and most strongly in China. Data are from representative national samples in 27 nations, with over 70,000 cases, analyzed using multi-level linear and probit models with multiple imputation of missing data.  相似文献   
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664.
Orphans and schooling in africa: a longitudinal analysis   总被引:4,自引:0,他引:4  
Evans DK  Miguel E 《Demography》2007,44(1):35-57
AIDS deaths could have a major impact on economic development by affecting the human capital accumulation of the next generation. We estimate the impact of parent death on primary school participation using an unusual five-year panel data set of over 20,000 Kenyan children. There is a substantial decrease in school participation following a parent death and a smaller drop before the death (presumably due to pre-death morbidity). Estimated impacts are smaller in specifications without individual fixed effects, suggesting that estimates based on cross-sectional data are biased toward zero. Effects are largest for children whose mothers died and, in a novel finding, for those with low baseline academic performance.  相似文献   
665.
Despite numerous studies on motivation for generosity, much remains unknown. Given that the lion's share of giving and volunteering is directed toward religious institutions, we aimed to test the motivation for the generosity of Mormons. Previous research has indicated that Mormons (Latter‐day Saints) volunteer and donate at much higher levels than other groups. This study examined how self‐reported motivations to volunteer explain the annual number of hours volunteered and the likelihood of donating toward various causes. We used thirty qualitative interviews with Latter‐day Saints to create a comprehensive questionnaire measuring the time spent engaged in various volunteer activities and whether or not the respondents donated to various causes. The questionnaire also asked respondents to rank how important twenty‐five different motivations were to their service or volunteering. We used factor analysis of the results on the twenty‐five motivation items to identify underlying variables behind volunteer motivations, and we used the scores on the five resulting factors in multiple regression analyses to predict volunteer hours and logistic regression analyses to predict the likelihood of making donations. Different types of motivations predicted different types of volunteering and charitable giving. Theological motivations had the broadest impact and predicted religious volunteering, social volunteering to benefit church members, social volunteering through the church to benefit the community, religious donations, and donations toward social causes made through the church. After inserting control variables into our models, we found that none of the five types of motivations predicted secular volunteering or secular charitable giving. We conclude with managerial and conceptual implications of these and other results.  相似文献   
666.
In order to examine the way ethical decisions are made, we asked ethicists, regulatory officials, and experienced researchers to review a set of scenarios that depict important ethical tensions in research. The method employed was “protocol analysis,” a talk-aloud technique pioneered by cognitive scientists. Each individual was asked to make recommendations for courses of action. Later, we held a focus group of university faculty and staff with either institutional review board experience or research ethics training. They too were asked to recommend actions. The results show there are areas where the two data collection approaches agree, as well as areas of considerable difference. Implications for training in the responsible conduct of research are discussed.  相似文献   
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668.
Kelley CGE, Kelley SMC, Evans MDR, Kelley J. Attitudes toward home‐based employment for mothers of young children: Australian evidence
Int J Soc Welfare 2010: 19: 33–44 © 2008 The Author(s), Journal compilation © 2009 Blackwell Publishing Ltd and the International Journal of Social Welfare. People have mixed feelings about paid employment for mothers with young children. This might reflect opposition to women's work per se or, instead, fear that children are harmed by the mother's absence from the home. To find out, we developed new questions differentiating support for or opposition to mothers working for pay depending on whether the employment is home‐based or outside the home. Data from a large representative national sample of Australia (n= 1,324) show that public support for employment is about 30 percentage points greater if the mother works at home. Structural equation analyses show social differences in levels of support. Thus work at home provides a way of increasing labour force participation and earnings for mothers (with the welfare benefits that implies), which is congruent with public opinion.  相似文献   
669.
Anderson KA  Gaugler JE 《Omega》2006,54(4):301-318
The grief that certified nursing assistants (CNAs) experience following the deaths of nursing home residents has received scant attention in past research, particularly from an empirical standpoint. The purpose of this quantitative study was to investigate the grief experiences of CNAs in the nursing home setting and to identify and evaluate factors that may mediate or exacerbate grief. Participants (N=136) from 12 nursing homes completed self-administered surveys. Regression analyses revealed that CNAs with lower levels of perceived disenfranchised grief reported higher levels of personal growth, while CNAs with greater fear of death and those who experienced fewer deaths on the job reported higher levels of complicated grief. Practitioners and future researchers may benefit from these findings through the construction and implementation of interventions aimed at effectively enfranchising the grief experiences of this important group of healthcare workers.  相似文献   
670.
The World Health Organization has declared antibiotic resistance “one of the biggest threats to global health.” Mounting evidence suggests that antibiotic use in industrial-scale hog farming is contributing to the spread of antibiotic-resistant Staphylococcus aureus. To capture available evidence on these risks, we searched peer-reviewed studies published before June 2017 and conducted a meta-analysis of these studies’ estimates of the prevalence of swine-associated, antibiotic-resistant S. aureus in animals, humans, and the environment. The 166 relevant studies revealed consistent evidence of livestock-associated methicillin-resistant S. aureus (MRSA) in hog herds (55.3%) raised with antibiotics. MRSA prevalence was also substantial in slaughterhouse pigs (30.4%), industrial hog operation workers (24.4%), and veterinarians (16.8%). The prevalence of swine-associated, multidrug-resistant S. aureus (MDRSA)—with resistance to three or more antibiotics—is not as well documented. Nonetheless, sufficient studies were available to estimate MDRSA pooled prevalence in conventional hog operation workers (15.0%), workers’ household members (13.0%), and community members (5.37%). Evidence also suggests that antibiotic-resistant S. aureus can be present in air, soil, water, and household surface samples gathered in or near high-intensity hog operations. An important caveat is that prevalence estimates for humans reflect colonization, not active infection, and the health risks of colonization remain poorly understood. In addition, these pooled results may not represent risks in specific locations, due to wide geographic variation. Nonetheless, these results underscore the need for additional preventive action to stem the spread of antibiotic-resistant pathogens from livestock operations and a streamlined reporting system to track this risk.  相似文献   
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