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Community‐based organizations (CBOs) are now cast among the lead actors in welfare reform. But do they have adequate capacity to perform this critical leadership function? Early findings from fifteen state‐funded projects in Texas show that state planners must carefully assess the capacity of a CBO to initiate and sustain an innovation at the local level. The authors examine six organizational variables that predict success or failure: goals, management, technology, funding, community involvement, and performance.  相似文献   
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A tank car derailment in northern California in 1991 spilled metam sodium into the Sacramento River, and released its breakdown product, methyl isothiocyanate (MITC), into the air. This paper describes the risk evaluation process used. Over 240 individuals reported symptoms such as eye and throat irritation, dizziness, and shortness of breath. Reference exposure levels (RELs) for 1 hr were developed for MITC and compared to exposure concentrations. Ocular irritation in cats was the most sensitive endpoint reported. The no observed adverse effect level (NOAEL), divided by an uncertainty factor (UF) of 100, produced an REL of 0.5 ppb of MITC in air to prevent discomfort. An REL to prevent disability was estimated to be 40 ppb. An REL to prevent life-threatening injury was estimated to be 150 ppb. Measured MITC levels ranged from 0.2-37 ppb and estimated peak levels ranged from 140-1600 ppb. The usefulness of RELs for emergency planning is discussed.  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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This study assessed unmet service needs of rural older adults with Alzheimer's disease (AD) and identified factors that were related to these needs. Data were collected from 109 informal caregivers of AD patients. Over half of the patients experienced unmet service needs in 1 or more areas of activities of daily functioning. Informal caregiver burden and patient's gender and functional status were significantly related to patients' unmet service needs. Patients' use of formal services was marginally related to their unmet service needs. To better address patients' service needs, a comprehensive needs assessment should be conducted with both patients and their caregivers.  相似文献   
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This study identifies perspectives of relationships publics have about countries other than their own and examines whether publics engaged through social media-based public diplomacy programs demonstrate different relationship perspectives. Q methodology and survey research were used to investigate these issues. Data come from South Korean adult internet users, including members of Café USA, an online community run by the U.S. Embassy in Seoul. Three relationship perspectives were identified: outcome-based, sincerity-based, and access-based. Compared with other groups, Café USA members put more emphasis on sincerity in their relationships with the United States. The results of this study indicate that individuals’ subjectivity should be considered as far more contextualized and nuanced than has been the case in previous research on national image or country reputation.  相似文献   
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This study describes associations of partner‐specific relationship characteristics with consistent condom use among 297 young people (ages 13–24) with sexually transmitted diseases (STD). Relationship‐specific variables were relationship quality, reasons for sex, relationship duration, duration of sexual relationship, coital frequency, “established” versus “new” sexual partner, cohabitation, children, sexual coercion, and drug or alcohol use associated with coitus. Relationship characteristics associated with consistent condom use included lower relationship quality, lower emotional reasons for sex, lower coital frequency, sex with a new partner, noncohabitation, and not having a child with the partner. Controlling for sociodemographic variables, factors exhibiting independent associations with consistent condom use were lower relationship quality, lower coital frequency, and not having a child with the partner. While condom use with potentially high risk new partners is important, other types of relationships are also risky but associated with lower likelihood of consistent condom use. Better understanding of complex relationship characteristics is necessary to improve STD intervention programs.  相似文献   
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