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The objective of this work was to summarise and evaluate the evidence showing that physical activity is a protector factor as regards falls in older people. Relevant studies were identified through a systematic search in the MEDLINE and Cochrane Library, under the keywords of accidental fall/numerical data and risk factors, and with the bibliographies of retrieved papers. The combined odds ratio (OR) [95% confidence interval] for physical activity was 0.75 [0.64, 0.88] with moderate heterogeneity (I 2?=?33%). For fall injury, it was 0.59 [0.47, 0.74] and, for falls in general, it rose to 0.94 [0.76, 1.17] with nil heterogeneity. The combined OR for sedentary factors was 1.14 [1.10, 1.82] with moderate heterogeneity (I 2?=?36%). Regular physical activity in daily life yields significant reduction in falls in older people, especially falls with injuries.  相似文献   
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Much of the existing scholarly works portray institutional voids (IVs) in emerging economies as impeding forces against the development of new ventures. However, little attention has been paid to how such voids generate positive outcomes in emerging market new ventures. Drawing on the institutional theory, we propose IVs as crucial enablers of new venture internationalization. In addition, we investigate both how and when IVs enhance the degree to which new ventures internationalize by examining international learning effort (ILE) as a mediator and two domestic market environmental factors (i.e., environmental dynamism and competitive intensity) as important contingencies. We test our moderated mediation model using primary data gathered from 211 new ventures from Ghana. We found that ILE mediates the relationship between IVs and new venture internationalization and that both environmental dynamism and competitive intensity moderate the indirect relationship between home-country IVs and new venture internationalization. We discuss the theoretical and practical implications of this study.  相似文献   
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ABSTRACT

Social workers can mobilize vulnerable populations to shape policy decisions about industrial practices that could have adverse impacts on their wellbeing. One such practice is hydraulic fracturing or “fracking” to extract oil and natural gas from shale rock deposits. There is scant social work literature on mobilizing opposition to fracking despite a proliferation of literature from other disciplines. This article documents the campaign in Maryland that led to the adoption of the first legislative ban on fracking in a U.S. state with shale gas reserves, using social movement theory to identify factors that led to this successful outcome.  相似文献   
45.
Research on the determinants of foreign aid tends to focus on the relationship between donor country priorities and recipient state characteristics, but donors also make decisions about which organizations and programs within countries will receive assistance. Although NGOs increasingly have been recipients of foreign aid, few data are available to investigate which organizations within a given country receive that funding. Donors may prioritize structural characteristics of NGOs or their local ties—or they may seek a combination that blends concern about efficiency and accountability with an interest in developing national civil society. We use original data from Cambodia to explore whether aid is likely to go to managerial organizations (professionalized NGOs and NGOs that utilize modern management tools) or to organizations that are embedded in the domestic context. We argue that managerialism provides legitimacy for NGOs by signaling capacity and accountability to donors, increasing the likelihood of government funding. We argue that local embeddedness also confers legitimacy by aligning community ties and networks to rights-based development, increasing the likelihood of government funding. We find general support for the managerialism argument, but donor agencies do not prioritize direct funding for “indigenous” NGOs—not even among those with high levels of managerialism.  相似文献   
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Gender role differentiation intensifies during adolescence. The current study explores gender-role attitudes among unmarried young men and women aged 15–21 residing in the slums of Allahabad, India. The survey asked a series of questions about gender role attitudes to young men and women and to their parents (relating to work and educational attainment for girls, marriage and husband–wife relations). Since either the father or mother responded to the parent questionnaire, data analyses are based on subsets of mother–daughter pairs (n = 2124), mother–son pairs (n = 2135), father–son pairs (n = 788), and father–daughter pairs (n = 452). No significant differences emerged in terms of adolescent background characteristics of the four groups and the adolescent population of the study. A fair amount of congruence in gender role attitudes was found in the mother–daughter and father–son pairs for most items. However, a similar pattern was not visible in the father–daughter or mother–son pairs. Multivariate regression analysis indicated strong influence of parental attitudes on the adolescent’s attitudes. While education led to a shift in girls’ attitudes to gender egalitarian ones, it did not impact the attitudes of adolescent boys.  相似文献   
48.
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   
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Federal and other regulatory agencies often use or claim to use a weight of evidence (WoE) approach in chemical evaluation. Their approaches to the use of WoE, however, differ significantly, rely heavily on subjective professional judgment, and merit improvement. We review uses of WoE approaches in key articles in the peer‐reviewed scientific literature, and find significant variations. We find that a hypothesis‐based WoE approach, developed by Lorenz Rhomberg et al., can provide a stronger scientific basis for chemical assessment while improving transparency and preserving the appropriate scope of professional judgment. Their approach, while still evolving, relies on the explicit specification of the hypothesized basis for using the information at hand to infer the ability of an agent to cause human health impacts or, more broadly, affect other endpoints of concern. We describe and endorse such a hypothesis‐based WoE approach to chemical evaluation.  相似文献   
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