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Analytic webs support the synthesis of ecological data sets   总被引:1,自引:0,他引:1  
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OBJECTIVE: Teenagers have very high motor vehicle crash rates, and their use of seat belts is generally lower than that of adults. A potential school-based strategy to increase teenagers' belt use is a policy making parking privileges contingent on belt use by student drivers and their passengers. This study evaluated the effects of implementing a school belt policy. METHODS: The effects of a belt policy were evaluated during the 2003-2004 school year at high schools in two states: Connecticut, a state with a primary enforcement belt law and high belt use rates, and Mississippi, a state with a secondary enforcement law and generally low use rates. Both schools enforced the policy, and violations resulted in a graduated set of penalties leading to the potential loss of parking privileges. Baseline and post-policy belt use rates were obtained from observation surveys of student drivers and their teenage passengers coming to and from school. Changes in belt use were examined relative to belt use trends at comparison schools without a belt policy. Implementation of the policies also was monitored. RESULTS: In Mississippi, among students arriving at school in the morning, driver belt use increased from 42% before the policy to 67% about 6 months after; passenger belt use increased from 16% to 61%, although sample sizes were small. These increases were significantly larger than expected, based on belt use trends at the comparison school in Mississippi. In Connecticut, where 86% of drivers and 79% of their passengers already were belted prior to the policy, there was no significant change. Both schools publicized and monitored the belt policy, and most enforcement occurred in the morning as students arrived at school. CONCLUSIONS: Based on a small-scale application of a belt policy at two schools in different states, a school belt policy may have stronger effects in states where belt use is low. Strong penalties and enforcement are essential elements of an effective policy. Adequate resources and commitment are needed for schools to implement and monitor the type of strong policy needed to sustain high belt use rates. Replication of this study in additional schools appears warranted.  相似文献   
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INTRODUCTION: Many injury prevention interventions require changes in human behavior to reduce self-risk or risk to others. Promising injury prevention interventions may be discarded if they lack power to create a significant difference in outcomes when judging their ability to "move a person from nonaction or negative action to positive action (safety)." The transtheoretical model of change (TMC) allows greater sensitivity in detecting along the change process where an intervention may be effective. The stages of change consist of precontemplation, contemplation, preparation, action, maintenance, and termination. Change is not viewed as an "all or none phenomenon." METHOD: Use of the TMC was examined using a quasiexperimental, cross-over design involving high school agriculture students enrolled in 21 schools in Kentucky (n=9), Iowa (n=7), and Mississippi (n=5). A series of physical and narrative simulations (safety training exercises) were developed with a focus on preventing amputation, spinal cord injury, hypersensitivity pneumonitis, and noise-induced hearing loss. Contemplation and action, as part of the TMC, were measured using a 10-item, Likert-type, stages of change (SOC) instrument comprised of two subscales (reliability coefficients were.88 and.81, respectively). The final sample consisted of 790 students (373 treatment and 417 control). RESULTS: There was a significant group effect for both contemplation, F(1,732)=197.4; p<.0001, and action, F(1,730)=106.1; p<.0001. A convenience sample of 29 of the participating students was selected for follow-up farm visits 1 year postparticipation. Of these students, 25 (86%) had made safety behavior changes in their farm work. IMPACT ON INDUSTRY: The use of the TMC model can provide researchers with greater precision in examining intervention effectiveness in promoting change.  相似文献   
55.
Population declines in four species of eider; common (Somateria mollissima), king (Somateria spectabilis), spectacled (Somateria fischeri) and Steller's (Polysticta stelleri), have raised concerns about exposure to contaminants. Livers and kidney tissues were collected from eiders in Alaska and Russia for organic and elemental analyses. Results showed that organochlorine and many elemental levels were below toxic thresholds; however, in many cases, cadmium, copper, lead and serenium appeared high relative to other waterfowl and may warrant concern. With the exception of lead, local anthropogenic sources for these elements are not known. Although adverse physiological responses have not been documented in eiders, these four elements cannot be ruled out as contaminants of potential concern for some eider species.  相似文献   
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The spatial congruence of chemical and biological recovery along an 18-km acid mine impaired stream was examined to evaluate the efficacy of treatment with an alkaline doser. Two methods were used to evaluate biological recovery: the biological structure of the benthic macroinvertebrate community and several ecosystem processing measures (leaf litter breakdown, microbial respiration rates) along the gradient of improved water chemistry. We found that the doser successfully reduced the acidity and lowered dissolved metals (Al, Fe, and Mn), but downstream improvements were not linear. Water chemistry was more variable, and precipitated metals were elevated in a 3–5-km “mixing zone” immediately downstream of the doser, then stabilized into a “recovery zone” 10–18 km below the doser. Macroinvertebrate communities exhibited a longitudinal pattern of recovery, but it did not exactly match the water chemistry gradient Taxonomic richness (number of families) recovered about 6.5 km downstream of the doser, while total abundance and % EPT taxa recovery were incomplete except at the most downstream site, 18 km away. The functional measures of ecosystem processes (leaf litter breakdown, microbial respiration of conditioned leaves, and shredder biomass) closely matched the measures of community structure and also showed a more modest longitudinal trend of biological recovery than expected based on pH and alkalinity. The measures of microbial respiration had added diagnostic value and indicated that biological recovery downstream of the doser is limited by factors other than habitat and acidity/alkalinity, perhaps episodes of AMD and/or impaired energy/nutrient inputs. A better understanding of the factors that govern spatial and temporal variations in acid mine contaminants, especially episodic events, will improve our ability to predict biological recovery after remediation.  相似文献   
57.
Analytical methods for the determination of trace beryllium in soils are needed so that anthropogenic sources of this element can be distinguished from native (background) levels of beryllium. In this work, a collaborative interlaboratory evaluation of a new extraction and fluorescence-based procedure for determining beryllium in soil samples was carried out to fulfil method validation requirements for ASTM International voluntary consensus standard test methods. A Canadian reference material, CCRMP Till-1 soil, with a background beryllium concentration of 2.4 microg g(-1), was selected for study. This certified reference material (CRM) was spiked and homogenized with varying levels of beryllium oxide in order to give batches of material with beryllium concentrations of 4.36 +/- 0.69, 11.5 +/- 0.7, 124 +/- 7 and 246 +/- 16 microg g(-1) (+/- values are standard deviations). In the interlaboratory study (ILS), which was carried out in accordance with an applicable ASTM International standard practice (ASTM E691), samples of these spiked soils were subjected to extraction in dilute ammonium bifluoride at approximately 90 degrees C for 40 h. Fluorescence measurement of the extracted beryllium was carried out via detection using the high quantum yield fluorophore, hydroxybenzoquinoline sulfonate (HBQS). Interlaboratory precision estimates from six participating laboratories ranged from 0.048 to 0.103 (relative standard deviations) for the five different beryllium concentrations. Pooled bias estimates resulting from this ILS were between -0.049 and 0.177 for the various beryllium levels. These figures of merit support promulgation of the analytical procedure as an ASTM International standard test method.  相似文献   
58.
ABSTRACT: Shallow ground water in areas of increasing urban development within the Upper Colorado River Basin was sampled for inorganic and organic constituents to characterize water‐quality conditions and to identify potential anthropogenic effects resulting from development. In 1997, 25 shallow monitoring wells were installed and sampled in five areas of urban development in Eagle, Grand, Gunnison, and Summit Counties, Colorado. The results of this study indicate that the shallow ground water in the study area is suitable for most uses. Nonparametric statistical methods showed that constituents and parameters measured in the shallow wells were often significantly different between the five developing urban areas. Radon concentrations exceeded the proposed USEPA maximum contaminant level at all sites. The presence of nutrients, pesticides, and volatile organic compounds indicate anthropogenic activities are affecting the shallow ground‐water quality in the study area. Nitrate as N concentrations greater than 2.0 mg/L were observed in ground water recharged between the 1980s and 1990s. Low concentrations of methylene blue active substances were detected at a few sites. Total coliform bacteria were detected at ten sites; however, E. coli was not detected. Continued monitoring is needed to assess the effects of increasing urban development on the shallow ground‐water quality in the study area.  相似文献   
59.
This paper reviews the literature on the effects of post-disaster relocation on physical and mental heath, and develops a conceptual framework to guide future research. Forty articles were selected for full-text review and incorporation into the conceptual framework. Twenty-four articles were reviewed for results and methodology. These overwhelmingly tracked mental health outcomes. Only four (16 per cent) focused on physical health. Eight of ten showed an association between relocation and psychological morbidity. Certain outcomes (such as mortality, injury and cardiovascular disease risk factors) revealed inconsistent results, but these were rarely studied. Despite the frequency of post-disaster relocation and evidence of its effect on psychological morbidity, there is a relative paucity of studies; the few examples in the literature reveal weak study designs, inconsistent results, and inattention to physical health impacts and the challenges facing vulnerable populations. Further research guided by theory is needed to inform emergency preparedness and recovery policy.  相似文献   
60.

Problem

As the evidence-based movement has advanced in public health, changes in public health practices have lagged far behind creating a science to service gap. For example, science has produced effective falls prevention interventions for older adults. It now is clearer WHAT needs to be done to reduce injury and death related to falls. However, issues have arisen regarding HOW to assure the full and effective uses of evidence-based programs in practice.

Summary

Lessons learned from the science and practice of implementation provide guidance for how to change practices by developing new competencies, how to change organizations to support evidence-based practices, and how to change public health systems to align system functions with desired practices. The combination of practice, organization, and system change likely will produce the public health benefits that are the promise of evidence-based falls prevention interventions.

Impact on public health

For the past several decades, the emphasis has been solely on evidence-based interventions. Public health will benefit from giving equal emphasis to evidence-based implementation.

Impact on Industry

We now have over two decades of research on the effectiveness of fall prevention interventions. The quality of this research is judged by a number of credible international organizations, including the Cochrane Collaboration (http://www.cochrane.org/), the American and British Geriatrics Societies, and the Campbell Collaboration (http://www.campbellcollaboration.org/). These international bodies were formed to ponder and answer questions related to the quality and relevance of research. These developments are a good first step. However, while knowing WHAT to do (an evidence-based intervention) is critical, we also need to know HOW to effectively implement the evidence. Implementation, organization change, and system change methods produce the conditions that allow and support the full and effective use of evidence-based interventions. It is time to focus on utilization of implementation knowledge in public health. Without this focus the vast amount on new evidence being generated on the prevention of falls and related injuries among older adults will have little impact on their health and safety.  相似文献   
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