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151.
The author discusses the limitations of statistical forecasting as a guide to managerial planning, with specific reference to technological and market changes in the glass industry. He advocates the use of a Forecast Adjustment Matrix as a framework for identifying marketing and technological factors which might produce significant deviations from established trends. Finally, he suggests that the analysis and adjustment of technological and market trends should be made periodically. The whole technological forecasting operation should be formalized and it should be made the specific responsibility of one organizational unit within the company.  相似文献   
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153.
Food insufficiency is a significant problem in the United States, and poor African American women with children are at especially high risk. An inadequate household food supply can potentially affect the well-being of household members, but it is difficult to distinguish the effects of food insufficiency from risk factors for poor health that are also common among the food insufficient, such as poverty. We examined food insufficiency and physical and mental health among African American and white women (n = 676) who were welfare recipients in 1997. Controlling for common risk factors, women who reported food insufficiency in both 1997 and 1998 were more likely to report fair or poor health at the later date. Food insufficiency in 1998 was significantly associated with meeting the diagnostic screening criteria for recent major depression. Food insufficiency at both times and in 1998 only was related to women's sense of mastery. These findings add to growing evidence that household food insufficiency is associated with poor physical and mental health.  相似文献   
154.
The author's dual-purpose evaluation assesses the effectiveness of formal collaboratives in stimulating organizational changes to improve chronic illness care (the chronic care model or CCM). Intervention and comparison sites are compared before and after introduction of the CCM. Multiple data sources are used to measure the degree of implementation, patient-level processes and outcomes, and organizational and team factors associated with success. Despite challenges in timely recruitment of sites and patients, data collection on 37 participating organizations, 22 control sites, and more than 4,000 patients with diabetes, congestive heart failure, asthma, or depression is nearing completion. When analyzed, these data will shed new light on the effectiveness of collaborative improvement methods and the CCM.  相似文献   
155.
Where strength training has been used in conjunction with functional-task training in older people, not only have there been improvements in leg strength but also improved function has been measured (e.g., Skelton & McLaughlin, 1996). Many studies use participants from care homes rather than community dwellers. We investigated changes in leg power, balance, and functional mobility in community-dwelling sedentary men and women over 70 years of age (n = 6 for training group [TR]; n = 10 for control group [CN]). Progressive training took place over 24 weeks using seated and nonseated exercise. For TR, leg power increased 40%, from 108 +/- 40 to 141 +/- 53 W (p < .01); dynamic balance increased 48%, from 22.3 +/- 7.9 to 33.1 +/- 6.1 cm (p < .01; functional reach); and functional mobility increased 12%, from 7.46 +/- 1.32 to 6.54 +/- 1.41 s (p < .05; timed walk). CN showed no significant change. In conclusion, a community-based exercise program led to large improvements in leg-extensor power, dynamic balance, and functional mobility.  相似文献   
156.
An estimation of the human lung cancer “unit risk” from diesel engine particulate emissions has been made using a comparative potency approach. This approach involves evaluating the tumorigenic and mutagenic potencies of the particulates from four diesel and one gasoline engine in relation to other combustion and pyrolysis products (coke oven, roofing tar, and cigarette smoke) that cause lung cancer in humans. The unit cancer risk is predicated on the linear nonthreshold extrapolation model and is the individual lifetime excess lung cancer risk from continuous exposure to 1 μg carcinogen per m3 inhaled air. The human lung cancer unit risks obtained from the epidemiologic data for coke oven workers, roofing tar applicators, and cigarette smokers were, respectively, 9.3 × 10?4, 3.6 × 10?4, and 2.2 × 10?6 per μg particulate organics per m3 air. The comparative potencies of these three materials and the diesel and gasoline engine exhaust particulates (as organic extracts) were evaluated by in vivo tumorigenicity bioassays involving skin initiation and skin carcinogenicity in SENCAR mice and by the in vitro bioassays that proved suitable for this analysis: Ames Salmonella microsome bioassay, L5178Y mouse lymphoma cell mutagenesis bioassay, and sister chromatid exchange bioassay in Chinese hamster ovary cells. The relative potencies of the coke oven, roofing tar, and cigarette smoke emissions, as determined by the mouse skin initiation assay, were within a factor of 2 of those determined using the epidemiologic data. The relative potencies, from the in vitro bioassays as compared to the human data, were similar for coke oven and roofing tar, but for the cigarette smoke condensate the in vitro tests predicted a higher relative potency. The mouse skin initiation bioassay was used to determine the unit lung cancer risk for the most potent of the diesel emissions. Based on comparisons with coke oven, roofing tar, and cigarette smoke, the unit cancer risk averaged 4.4 × 10?4. The unit lung cancer risks for the other, less potent motor-vehicle emissions were determined from their comparative potencies relative to the most potent diesel using three in vitro bioassays. There was a high correlation between the in vitro and in vivo bioassays in their responses to the engine exhaust particulate extracts. The unit lung cancer risk per μg particulates per m3 for the automotive diesel and gasoline exhaust particulates ranged from 0.20 × 10?4 to 0.60 × 10?4; that for the heavy-duty diesel engine was 0.02 × 10?4. These unit risks provide the basis for a future assessment of human lung cancer risks when combined with human population exposure to automotive emissions.  相似文献   
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158.
Effective targeted and community HIV/STD prevention programs   总被引:1,自引:0,他引:1  
Community interventions and interventions targeting specific groups at risk of STDs/HIV have demonstrated significant impacts on sexual behavior, particularly condom use and safer sex. The scientific evidence suggests the factors that make these interventions particularly effective include the establishment of community, including business and CBO partnerships; maintainance of the intervention post-research funding; and buy-in by the community or target group. The modification of risky normative beliefs through the use of opinion leaders and role models, and through intervention delivery by peer educators, is an important facet of such interventions. Interventions delivered by health professionals, absent a community base, appear to be unsuccessful. Where cultures or subcultures are targeted, the close involvement of such groups in the design and delivery of messages is critical to their success. Diffusion of interventions through existing social networks further extends the intervention into the community and acts to reinforce and maintain changes in peer norms toward safer sexual behavior. The available data confirm that community or medical infrastructure-based interventions are effective in changing sexual behavior and can reach a wider range of the population than face-to-face programs if they incorporate peer educators as role models in modifying norms, and if diffusion of the intervention is integral to the design.  相似文献   
159.
Forgiveness is a significant intervention for healing interpersonal injury. Yet therapists do not often use forgiveness intervention. Employing a semantic perspective and a survey design (n = 307), this study investigated whether the language used to rationalize forgiveness intervention (set at five levels: personal growth, relationship reconciliation, spiritual issue, others' growth, and pardoning/condoning) may affect its acceptability. Gender, problem type, and choice were also included in the analyses. Overall, forgiveness was found to be an acceptable intervention. A pardoning/condoning rationale led to significantly lower acceptability ratings. Other results are discussed. We conclude that therapists should be less apprehensive about using forgiveness, but need to inform themselves better concerning its purpose, process, and articulation.  相似文献   
160.
Work-related musculoskeletal injuries represent a major source of work disability. While many employers recognize the importance of workplace disability management approaches and are assuming greater responsibility for preventing and minimizing work-related disability, questions about the effectiveness of these interventions exist. The purposes of this article are to: 1) describe the essential components of workplace disability management programs related to musculoskeletal injuries; 2) review the literature on disability management practices based on research evidence by focussing on workplace-based interventions and the role of the workplace; and 3) provide recommendations for disability management in the prevention and reduction of disability, and the rehabilitation of injured workers with musculoskeletal work injuries. The literature suggests that employer participation, a supportive work climate and cooperation between labour and management are crucial factors in facilitating return to work. Given the complexity of the disability management process and the numbers of individuals involved, it is essential that all workplace parties work together to achieve the goal of safe and early return to work.  相似文献   
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