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231.
The terrorist attacks of 11 September 2001 (9/11) left workplaces in pressing need of a mental health response capability. Unaddressed emotional sequelae may be devastating to the productivity and economic stability of a company's workforce. In the second year after the attacks, 85 employees of five highly affected agencies participated in 12 focus groups to discuss workplace mental health issues. Managers felt ill prepared to manage the magnitude and the intensity of employees' emotional responses. Rapid return to work, provision of workplace mental health services, and peer support were viewed as contributory to emotional recovery. Formal mental health services provided were perceived as insufficient. Drawing on their post‐9/11 workplace experience, members of these groups identified practical measures that they found helpful in promoting healing outside of professional mental health services. These measures, consistent with many principles of psychological first aid, may be applied by workplace leaders who are not mental health professionals.  相似文献   
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Increasing development of historic farmlands raises questions regarding the fate of pesticides applied when these land were in cultivation. We quantified As and Pb budgets in field soils in two orchards where arsenical pesticides were applied in the early 20th century and a third uncontaminated control field. Sequential extractions and X-ray analyses also were used to determine mineral phases. In addition, we measured metal loads in drainages adjacent to the fields and in two common macroinvertebrate taxa within the wetland at the outlet of the drainages. We find that the applied As and Pb have undergone little vertical redistribution; concentrations of As and Pb in the top 25 cm of contaminated orchard soils are higher than in the uncontaminated control field. However, none of the applied lead arsenate (PbHAsO4) remains in its original mineral phase. Instead, the metals are now primarily adsorbed onto fine silt and clay-sized amorphous oxides and organic matter. Further, physical erosion associated with tilling and replanting appears to have mobilized the fine-particulate-bound As and Pb in one orchard. The remobilized metals are found in sediments in the stream channel draining the tilled orchard. It is unclear if the As and Pb transported sediments are biologically active; average macroinvertebrate metal burdens in the wetland are not elevated above those observed elsewhere in the region. However, little of the mobilized metals may have reached the wetland. These results demonstrate that land use change can significantly impact the retention of arsenical pesticides.  相似文献   
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Reducing costs and increasing benefits for rural communities coexisting with large carnivores is necessary for conservation of jaguar (Panthera onca) and puma (Puma concolor). To design acceptable incentives, stakeholders must be involved in the process. We conducted an innovative, structured, group communication process based on a Delphi technique as a template for identifying potential incentives. Community workshops with 133 members of 7 communities and surveys with 25 multidisciplinary experts from government, nongovernmental organizations, and academia provided iterative data to design a plan of incentives through 4 rounds of discussion. The final product integrated 862 ideas into 6 types of incentives: organization of communities, mechanisms for improved dialogue, citizen technical assistance, green labeling for community products, payment for the ecosystem service of biodiversity, and an assessment of financial alternatives. We used quantitative and qualitative techniques to indicate support for decisions about the design of incentives, which reduced researcher subjectivity. The diverse incentives developed and the cooperation from multiple stakeholders resulted in an incentive plan that integrated issues of governance, equity, and social norms.  相似文献   
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Lead arsenate pesticides were widely used in apple orchards from 1925 to 1955. Soils from historic orchards in four counties in Virginia and West Virginia contained elevated concentrations of As and Pb, consistent with an arsenical pesticide source. Arsenic concentrations in approximately 50% of the orchard site soils and approximately 1% of reference site soils exceed the USEPA Preliminary Remediation Goal (PRG) screening guideline of 22 mg kg(-1) for As in residential soil, defined on the basis of combined chronic exposure risk. Approximately 5% of orchard site soils exceed the USEPA PRG for Pb of 400 mg kg(-1) in residential soil; no reference site soils sampled exceed this value. A variety of statistical methods were used to characterize the occurrence, distribution, and dispersion of arsenical pesticide residues in soils, stream sediments, and ground waters relative to landscape features and likely background conditions. Concentrations of Zn, Pb, and Cu were most strongly associated with high developed land density and population density, whereas elevated concentrations of As were weakly correlated with high orchard density, consistent with a pesticide residue source. Arsenic concentrations in ground water wells in the region are generally <0.005 mg L(-1). There was no spatial association between As concentrations in ground water and proximity to orchards. Arsenic had limited mobility into ground water from surface soils contaminated with arsenical pesticide residues at concentrations typically found in orchards.  相似文献   
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The entrainment of ambient water into non-Newtonian fluid mud gravity currents was investigated in this study. Constant volume release gravity currents were generated in a lock-exchange tank for a wide range of experimental conditions. A technique similar to the so-called light attenuation technique was used to find the boundary of the current, allowing for the calculation of both temporal and bulk entrainment parameters (in terms of the temporal and bulk entrainment velocities, respectively). It was found that the temporal entrainment velocity is dependent on different parameters in the different propagation phases. The slumping phase begins with an adjustment zone (henceforth, non-established zone) in which the temporal entrainment velocity is not a function of the current front velocity, followed by the established zone in which the temporal entrainment velocity is a function of the current front velocity. This dependence of the temporal entrainment velocity on the current front velocity carries through to the inertia-buoyancy phase. As expected, temporal entrainment velocity in the viscous-buoyancy phase was negligible in comparison to average entrainment velocity in the other phases. It is observed that the temporal entrainment characteristics in the non-established zone is governed by the competition between the entrainment-inhibiting density stratification effects and the entrainment-favouring effects of the Kelvin–Helmholtz billows that are quantified by the Richardson number and the Reynolds number of the gravity current, respectively. In the established zone, Reynolds number effects were observed to dominate over Richardson number effects in dictating temporal entrainment characteristics. A parameterization for the temporal entrainment velocity for non-Newtonian fluid mud gravity currents is developed based upon the experimental observations. This study also found that the bulk entrainment characteristics for the non-Newtonian fluid mud gravity currents can be parameterized by the Newtonian bulk entrainment parameterizations that rely solely on a bulk Richardson number. Interestingly, it was found that the non-Newtonian characteristics of the gravity current have little to no effect on the entrainment of the Newtonian ambient fluid.  相似文献   
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