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231.
Ten raw urban well water samples and twelve water samples collected from distribution lines after the well waters were treated were examined for bacteriological and coliphage/bacteriophage populations. The raw well waters were found to contain <1/100 ml total coliforms and fecal streptococci, but they all contained varying concentrations of coliphage and bacteriophage. The treated waters were all found to have <1 total coliforms and fecal streptococci per 100 ml with the exception of one treated water sample from Community C. However, even though the treated water samples contained free and total chlorine levels varying from 0.05 to 1.5 ppm, they were all found to contain usually greater amounts of coliphage and bacteriophage than the raw well waters.  相似文献   
232.
Purpose. The relationship between enterprise size and psychosocial working conditions has received little attention so far but some findings suggest that conditions are more favorable in small enterprises. This could have a positive impact on workers’ mental health. The objective of this study was to test the mediating effect of perceived working conditions in the relationship between enterprise size and anxious or depressive episodes. Methods. Data from the 2010 SUMER – Surveillance Médicale des Expositions aux Risques professionnels (French periodical cross-sectional survey) were analyzed; N?=?31,420 for the present study. Anxious or depressive episodes were measured with the hospital anxiety and depression scale and the perceived working conditions were psychological demand, decision latitude and social support as assessed with Karasek's job content questionnaire. The indirect effect was tested according to the method proposed by Preacher and Hayes. Results. In a multivariate logistic regression, the risk of anxious or depressive episodes was found to be lower in micro enterprises (2–9 employees). Formal tests pointed to a significant indirect effect of enterprise size on mental health through perceived working conditions, with a larger effect for psychological demand. Conclusion. This study highlights perceived working conditions as an explanation of the effects of enterprise size.  相似文献   
233.
Little research to date has focused on understanding employee motivation to share and hide knowledge. Using self‐determination theory, we tested the premise that knowledge sharing and hiding might be differentially motivated and that work design characteristics might influence the motivation to share knowledge with colleagues. In a panel survey of Australian knowledge workers and in a Chinese knowledge‐intensive organization, we asked knowledge workers, using time‐lagged designs, about perceptions of work design, motivation to share knowledge, and self‐reported knowledge sharing and hiding behaviors. Results, largely replicated across both samples, indicated that cognitive job demands and job autonomy were positively related to future reports of knowledge‐sharing frequency and usefulness via autonomous motivation to share knowledge. Unexpectedly, task interdependence was positively related to the three forms of knowledge hiding (evasive and rationalized hiding, and playing dumb) via external regulation to share knowledge. Implications for the design of jobs that motivate knowledge sharing and demotivate knowledge hiding are discussed.  相似文献   
234.
Citizen science has been gaining momentum in the United States and Europe, where citizens are literate and often interested in science. However, in developing countries, which have a dire need for environmental data, such programs are slow to emerge, despite the large and untapped human resources in close proximity to areas of high biodiversity and poorly known floras and faunas. Thus, we propose that the parataxonomist and paraecologist approach, which originates from citizen‐based science, is well suited to rural areas in developing countries. Being a paraecologist or a parataxonomist is a vocation and entails full‐time employment underpinned by extensive training, whereas citizen science involves the temporary engagement of volunteers. Both approaches have their merits depending on the context and objectives of the research. We examined 4 ongoing paraecologist or parataxonomist programs in Costa Rica, India, Papua New Guinea, and southern Africa and compared their origins, long‐term objectives, implementation strategies, activities, key challenges, achievements, and implications for resident communities. The programs supported ongoing research on biodiversity assessment, monitoring, and management, and participants engaged in non‐academic capacity development in these fields. The programs in Southern Africa related to specific projects, whereas the programs in Costa Rica, India, and Papua New Guinea were designed for the long term, provided sufficient funding was available. The main focus of the paraecologists’ and parataxonomists’ activities ranged from collection and processing of specimens (Costa Rica and Papua New Guinea) or of socioeconomic and natural science data (India and Southern Africa) to communication between scientists and residents (India and Southern Africa). As members of both the local land user and research communities, paraecologists and parataxonomists can greatly improve the flow of biodiversity information to all users, from local stakeholders to international academia.  相似文献   
235.
The North Atlantic right whale (NARW) (Eubalaena glacialis) is one of the world's most threatened whales. It came close to extinction after nearly a millennium of exploitation and currently persists as a population of only approximately 500 individuals. Setting appropriate conservation targets for this species requires an understanding of its historical population size, as a baseline for measuring levels of depletion and progress toward recovery. This is made difficult by the scarcity of records over this species’ long whaling history. We sought to estimate the preexploitation population size of the North Atlantic right whale and understand how this species was distributed across its range. We used a spatially explicit data set on historical catches of North Pacific right whales (NPRWs) (Eubalaena japonica) to model the relationship between right whale relative density and the environment during the summer feeding season. Assuming the 2 right whale species select similar environments, we projected this model to the North Atlantic to predict how the relative abundance of NARWs varied across their range. We calibrated these relative abundances with estimates of the NPRW total prewhaling population size to obtain high and low estimates for the overall NARW population size prior to exploitation. The model predicted 9,075–21,328 right whales in the North Atlantic. The current NARW population is thus <6% of the historical North Atlantic carrying capacity and has enormous potential for recovery. According to the model, in June–September NARWs concentrated in 2 main feeding areas: east of the Grand Banks of Newfoundland and in the Norwegian Sea. These 2 areas may become important in the future as feeding grounds and may already be used more regularly by this endangered species than is thought.  相似文献   
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238.
Moving a hospital is a critical period for quality and safety of healthcare. Change is very stressful for professionals. Workers who have experienced relocation of their place of work report deterioration in health status. Building a new hospital or restructuring a unit could provide an opportunity for improving safety and value in healthcare and for ensuring better quality of worklife for the staff. We used in situ simulation to promote experiential learning by training healthcare workers in the workplace in which they are expected to use their skills. In situ simulation was a way to design, plan, assess and implement a new healthcare environment before opening its doors for patient care. We can envisage that simulation will soon be used formally to identify potential problems in healthcare delivery and in staff quality of worklife in new healthcare facilities. Simulation is a way to co-produce a safe and valuable healthcare facility.  相似文献   
239.
ABSTRACT: The St. Johns River Water Management District (SJR-WMD) is using a Geographic Information System (GIS) screening model to estimate annual nonpoint source pollution loads to surface waters and determine nonpoint source pollution problem areas within the SJRWMD. The model is a significant improvement over current practice because it is contained entirely within the district's GIS software, resulting in greater flexibility and efficiency, and useful visualization capabilities. Model inputs consist of five spatial data layers, runoff coefficients, mean runoff concentrations, and stormwater treatment efficiencies. The spatial data layers are: existing land use, future land use, soils, rainfall, and hydrologic boundaries. These data layers are processed using the analytical capabilities of a cell-based GIS. Model output consists of seven spatial data layers: runoff, total nitrogen, total phosphorous, suspended solids, biochemical oxygen demand, lead, and zinc. Model output can be examined visually or summarized numerically by drainage basin. Results are reported for only one of the SJRWMD's ten major drainage basins, the lower St. Johns River basin. The model was created to serve a major planning effort at the SJRWMD; results are being actively used to address nonpoint source pollution problems.  相似文献   
240.
The aim of the present study is to assess whether certain ecophysiological responses (contents of total phenols, total proanthocyanidins, and total and simple flavonols), in the needles of Aleppo pines (Pinus halepensis Mill.) may be valid bioindicators for the assessment of the air quality. Samples were taken at five natural sites polluted by various pollutants (NO, NO2, other NOx, SO2, and O3). The results show a decrease in total phenol concentrations with levels of nitrogen oxide pollutions (significant negative correlations between the total phenol concentrations and concentrations of NO, NO2, and other NOx). Total flavonoids (total flavonols and proanthocyanidins) are useful bioindicators for ozone pollution (significant negative correlations between total proanthocyanidins and the concentrations of ozone and significant positive correlations between total flavonols and the ozone pollution). Sulfur dioxide pollution is distinguished by low concentrations in quercetin, isorhamnetin, and kaempferol (significant negative correlations between these simple flavonols and the concentrations of SO2). This work confirms the strong interest of using the phenolic compounds of Pinus halepensis as biological indicators of air quality.  相似文献   
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