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961.
This study evaluates the ability of the Catchment SIMulation (CSIM) hydrologic model to describe seasonal and regional variations in river discharge over the entire Baltic Sea drainage basin (BSDB) based on 31 years of monthly simulation from 1970 through 2000. To date, the model has been successfully applied to simulate annual fluxes of water from the catchments draining into the Baltic Sea. Here, we consider spatiotemporal bias in the distribution of monthly modeling errors across the BSDB since it could potentially reduce the fidelity of predictions and negatively affect the design and implementation of land‐management strategies. Within the period considered, the CSIM model accurately reproduced the annual flows across the BSDB; however, it tended to underpredict the proportion of discharge during high‐flow periods (i.e., spring months) and overpredict during the summer low flow periods. While the general overpredictions during summer periods are spread across all the subbasins of the BSDB, the underprediction during spring periods is seen largely in the northern regions. By implementing a genetic algorithm calibration procedure and/or seasonal parameterization of subsurface water flows for a subset of the catchments modeled, we demonstrate that it is possible to improve the model performance albeit at the cost of increased parameterization and potential loss of parsimony.  相似文献   
962.
This study proposes a robust prioritization framework for climate change adaptation strategies under uncertain climate change scenarios, using the VIseKriterijumska Optimizacija I Kompromisno Resenje (VIKOR) method, a multi‐criteria decision‐making approach, together with the Shannon entropy‐based weights. The VIKOR method allows us to find a compromise solution between two decision strategies of maximizing group utility and minimizing individual regret, and the Shannon entropy is used to determine objective weights among multiple climate change scenarios. The proposed methodology was applied to the problem of selecting locations of subwatersheds for reusing treated wastewater (TWW) in a Korean urban watershed. Selected based on the sustainability concept, hydro‐environmental and socioeconomic indicators were used to evaluate the sustainability of TWW reuse under multiple climate change scenarios, using the hydrologic simulation model results and statistical data. Finally, sustainability scores under multiple scenarios were aggregated using the VIKOR together with the Shannon entropy‐based weights for the robust prioritization of adaptation strategies. According to the different levels of regret aversion or affinity, our results for water quality showed different sets of adaptation strategies as the best options, suggesting that our framework would help stakeholders seeking the robust options considering both the utility and regret.  相似文献   
963.
Petroleum hydrocarbons are considered one of the main organic chemicals found in water bodies. In the present study, the median lethal concentration (LC50) was estimated for mullet Mugil liza after acute exposure to petroleum water-soluble fraction (PWSF). Furthermore, histopathological studies and micronuclei frequency were also performed in order to observe deleterious effects of medium-term exposition to PWSF. Mullets (25?±?2.3 g) were exposed to chronic concentrations (1.7, 3.5 and 7 % of PWSF), plus the control group, for 14 and 7 days of clearance time. Throughout the experimental period (1, 4, 14 and 21 days), blood samples were collected for analysis of micronucleus (MN) and liver and gills for histopathological study. For these procedures, seven fish were sampled per concentration tested. The LC50-96 h was estimated at 37.5 % of the PWSF. The time required for MN induction was 96 h of exposure. The time of clearance was sufficient to achieve a MN frequency similar to that of the control group. Histopathological studies showed severe changes in the gill and liver tissues. The most relevant histopathology in the gills was telangiectasia. Hepatic histopathology such as cholestasis, dilated sinusoids and inflammatory infiltrates were commonly described. The MN test and histological study effectively detected damages caused by medium-term exposition to the PWSF, and despite the toxicity, a few days without exposure can minimize PWSF genotoxicity in juveniles of M. liza.  相似文献   
964.
The 14th European Association of Chemical and Molecular Sciences (EuCheMS) International Conference on Chemistry and the Environment (ICCE 2013) took place on 25–28 June 2013 at the IEC and the WTC in Barcelona, Spain. The ICCE is a well-established biannual conference organized by the Division of Chemistry and the EuCheMS.  相似文献   
965.
Several studies indicate that mortality and morbidity can be well correlated to atmospheric aerosol concentrations with aerodynamic diameter less than 2.5 µm (PM2.5). In this work the PM2.5 at Recife city was analyzed as part of a main research project (INAIRA) to evaluate the air pollution impact on human health in six Brazilian metropolitan areas. The average concentration, for 309 samples (24-hr), from June 2007 to July 2008, was 7.3 µg/m³, with an average of 1.1 µg/m³ of black carbon. The elemental concentrations of samples were obtained by x-ray fluorescence. The concentrations were then used for characterizing the aerosol, and also were employed for receptor modelling to identify the major local sources of PM2.5. Positive matrix factorization analysis indicated six main factors, with four being associated to soil dust, vehicles and sea spray, metallurgical activities, and biomass burning, while for a chlorine factor, and others related to S, Ca, Br, and Na, we could make no specific source association. Principal component analysis also indicated six dominant factors, with some specific characteristics. Four factors were associated to soil dust, vehicles, biomass burning, and sea spray, while for the two others, a chlorine- and copper-related factor and a nickel-related factor, it was not possible to do a specific source association. The association of the factors to the likely sources was possible thanks to meteorological analysis and sources information. Each model, although giving similar results, showed factors’ peculiarities, especially for source apportionment. The observed PM2.5 concentration levels were acceptable, notwithstanding the high urbanization of the metropolitan area, probably due to favorable conditions for air pollution dispersion. More than a valuable historical register, these results should be very important for the next analysis, which will correlate health data, PM2.5 levels, and sources contributions in the context of the six studied Brazilian metropolises.
Implications: The analysis of fine particulate matter (PM2.5) in Recife city, Brazil, gave a significant picture of the local concentration and composition of this pollutant, which exhibits robust associations to adverse human health effects. Data from 1 year of sampling evaluated the seasonal variability and its connections with weather patterns. Source apportionment in this metropolitan area was obtained based in a combination of receptor models: principal component analysis (PCA)/chemical mass balance (CMB) and positive matrix factorization (PMF). These results give guidelines for local air pollution control actions, providing significant information for a health study in the context of establishing a new national air pollution protocol based on Brazilian cities data.  相似文献   
966.
Embeddedness theory has been invoked to describe factors that constrain employee turnover, such as fit with the environment, interpersonal links, and potentially sacrificed benefits. In contrast with previous assumptions that embeddedness requires considerable time to develop on the job, we extend theory by demonstrating how biographical characteristics (i.e., biodata), assessed at or before the point of hire, are related to individual's propensity to be embedded, while also showing how such characteristics predict one's future turnover likelihood. Beyond voluntary turnover, we also build embeddedness‐based theoretical explanations for involuntary turnover (i.e., terminations). To test these ideas, we conducted two studies at and before employees' point of hire, respectively: Study 1 examined how assessed biodata items of new employees relate to established embeddedness measures, whereas Study 2 linked the same biodata items assessed during the application process to employees' future involuntary, avoidable voluntary, and unavoidable voluntary turnover. Study 1 results revealed various biodata items predicted embeddedness in two distinct samples. In Study 2, results showed that biodata predicted turnover forms in unique ways. Our study highlights the utility of point‐of‐hire embeddedness propensity as a means to explain organizational exit, thereby demonstrating how organizations can use embeddedness tenets for employee recruitment and selection purposes.  相似文献   
967.
Drawing on fairness heuristics theory (Lind, 2001) and cue consistency theory (Maheswaran & Chaiken, 1991; Slovic, 1966), we test a moderated mediation model that examines whether the institutionalization of organizational socialization tactics enhances or constrains the beneficial effects of supervisory and coworker‐referenced justice and support on newcomer role clarity and social integration. The findings of a three‐wave study of 219 French newcomers show that although institutionalized tactics strengthen the positive indirect effects of supervisory interpersonal and informational justice on role clarity, via perceived supervisor support, it also acts as a substitute that weakens the positive indirect effect of coworker‐referenced interpersonal justice on social integration, via perceived coworker support. Implications of the findings for socialization research and practice are discussed.  相似文献   
968.
969.
ABSTRACT: A curve number based model, Soil and Water Assessment Tool (SWAT), and a physically based model, Soil Moisture Distribution and Routing (SMDR), were applied in a headwater watershed in Pennsylvania to identify runoff generation areas, as runoff areas have been shown to be critical for phosphorus management. SWAT performed better than SMDR in simulating daily streamflows over the four‐year simulation period (Nash‐Sutcliffe coefficient: SWAT, 0.62; SMDR, 0.33). Both models varied streamflow simulations seasonally as precipitation and watershed conditions varied. However, levels of agreement between simulated and observed flows were not consistent over seasons. SMDR, a variable source area based model, needs further improvement in model formulations to simulate large peak flows as observed. SWAT simulations matched the majority of observed peak flow events. SMDR overpredicted annual flow volumes, while SWAT underpredicted the same. Neither model routes runoff over the landscape to water bodies, which is critical to surface transport of phosphorus. SMDR representation of the watershed as grids may allow targeted management of phosphorus sources. SWAT representation of fields as hydrologic response units (HRUs) does not allow such targeted management.  相似文献   
970.
This study investigated attitudes and subjective norms related to workplace diversity initiatives and intentions to engage in diversity‐related behaviors in a sample of 852 public service employees. Participants completed a survey measuring behavioral intentions, attitudes, belief‐based norms, ethnic identity achievement, and demographic characteristics. Comparisons were made between people of color and Whites as well as between those with high and low ethnic identity achievement. Results showed a triple interaction among supervisor race, employee race, and employee ethnic identity achievement. Specifically, among people of color with high ethnic identity achievement, having a supervisor of color was more strongly associated with positive views of subjective norms toward inclusive behavior, understanding others, and treating others with respect than among people of color with low ethnic identity achievement. Implications of these findings and directions for future research are discussed. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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