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101.
Urban Ecosystems - We introduce a conceptual model of the urban forest patch as a complex social-ecological system, incorporating cross-scale interactions. We developed this model through an...  相似文献   
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Marketing practices that promote calorie-dense, nutrient-poor foods directly to children and adolescents present significant public health risk. Worldwide, calls for government action and industry change to protect young people from the negative effects of food marketing have increased. Current proposals focus on restricting television advertising to children under 12 years old, but current psychological models suggest that much more is required. All forms of marketing pose considerable risk; adolescents are also highly vulnerable; and food marketing may produce far-reaching negative health outcomes. We propose a food marketing defense model that posits four necessary conditions to effectively counter harmful food marketing practices: awareness, understanding, ability, and motivation to resist. A new generation of psychological research is needed to examine each of these processes, including the psychological mechanisms through which food marketing affects young people, to identify public policy that will effectively protect them from harmful influence.  相似文献   
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We use ecological systems theory to guide our investigation of depression among a sample of 102 married Black mothers residing in the rural South. Using self‐report data collected via computerized interviews during home visits, we conduct multivariate regression analyses, exploring the associations between depression and (a) spousal support and conflict, (b) cocaregiver support and conflict, (c) child conduct difficulties, and (d) socioeconomic risk. We hypothesize that each of these variables are associated with mothers' depression scores and that the extent to which these familial variables and depression are associated will vary across socioeconomic contexts. Socioeconomic risk, child conduct difficulties, and conflict with a cocaregiver were associated with women's depression in the full model. The moderational hypotheses were upheld for the variables of spousal support and child conduct difficulty. Spousal support and depression have a strong negative association under conditions of high socioeconomic risk and a nonsignificant relationship when socioeconomic risk is low. The association between child conduct difficulty and depression was exacerbated under high socioeconomic risk.  相似文献   
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Summary Social work research is constantly diversifying and expandingand this article explores its changing nature; including changesto epistemology and practice; and the critical influence ofthe wider economic, political, theoretical and practice changesoccurring to social work itself. The author discusses a numberof issues facing social work research: the enduring conflictsof ways of knowing, doing and valuing social work research;the role of practitioners as researchers; and the challengeto empower service users as self-determining researchers.  相似文献   
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The authors look back more than 30 years to those who introduced the use of the computer as an important new tool to assist students in the area of career development. To what extent have dreams been realized and concerns allayed? Rapid advances in technology, not included in the authors' vision, have transformed the world into a different place. How have these advances affected the use of computers in counseling? The article concludes with a list of current concerns, along with recommendations for further action and research.  相似文献   
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Biomonitoring programs for urinary chromium (Cr) typically attempt to evaluate occupational exposure via the inhalation route. This study investigated whether Cr can be detected in the urine of people following the ingestion of soils that contain relatively high concentrations of chromium in chromite ore processing residue (COPR). To evaluate the reasonableness of using urinary monitoring to assess environmental exposure, six volunteers ingested 400 mg of soil/day (low-dose group), two others ingested 2.0 g of soil/day (high-dose group) for 3 consecutive days, and one person ingested a placebo on each of 3 days. The soil and COPR mixture contained concentrations of total chromium (Cr) and hexavalent chromium [Cr(VI)] of 103 ± 20 and 9.3 ± 3.8 mg/kg, respectively. Therefore, the low-dose group ingested 41 μg Cr/day [including 3.7 μg Cr(VI)] and the high-dose group ingested 206 μg Cr/day [including 18.6 μg Cr(VI)] on each of 3 consecutive days. All urine samples were collected and analyzed individually for total Cr on the day prior to dosing, during the 3 days of dosing, and up to the first void 48 h after the last dose. No significant increases in urinary Cr excretion were found when background excretion data were compared with data following each of the 3 days of dosing or in daily mean urine concentrations of the high- vs the low-dose groups. It appears that Cr present in a soil and COPR mixture at Cr doses up to 200 μg/day is not sufficiently bioavailable for biomonitoring of urine to be informative. These results are consistent with previously published findings suggesting that incidental exposure to dusts and soils containing comparable levels of Cr will not result in increased concentrations of Cr in urine.  相似文献   
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Although recent studies examine overall fertility trends in West Africa, few using advanced demographic techniques focus on adolescents. This study explores long‐term patterns of adolescent childbearing in 12 West African countries using 51 Demographic and Health Surveys covering birth cohorts that span 54 years (1940–1994). We employ classic demographic measures as well as disaggregation by early‐ (10–14 years old), middle‐ (15–17), and late adolescence (18–19). Cohort‐based estimates of total adolescent births, parity progression ratios, and rapid repeat birth probabilities reveal little change over time. Most women begin childbearing in adolescence, the progression to additional adolescent births remains common, and the incidence of rapid repeat births is high. In recent cohorts, women exit adolescence with an average of between 0.4 (Ghana) to 1.3 (Niger) births. Contrary to common assumptions, it is women commencing motherhood in early‐ and middle‐, not later adolescence, who account for most West African adolescent fertility.  相似文献   
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