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1.
BACKGROUND: Epidemiological studies that assess the health effects of long-term exposure to ambient air pollution are used to inform public policy. These studies rely on exposure models that use data collected from pollution monitoring sites to predict exposures at subject locations. Land use regression (LUR) and universal kriging (UK) have been suggested as potential prediction methods. We evaluate these approaches on a dataset including measurements from three seasons in Los Angeles, CA. METHODS: The measurements of gaseous oxides of nitrogen (NOx) used in this study are from a "snapshot" sampling campaign that is part of the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air). The measurements in Los Angeles were collected during three two-week periods in the summer, autumn, and winter, each with about 150 sites. The design included clusters of monitors on either side of busy roads to capture near-field gradients of traffic-related pollution. LUR and UK prediction models were created using geographic information system (GIS)-based covariates. Selection of covariates was based on 10-fold cross-validated (CV) R(2) and root mean square error (RMSE). Since UK requires specialized software, a computationally simpler two-step procedure was also employed to approximate fitting the UK model using readily available regression and GIS software. RESULTS: UK models consistently performed as well as or better than the analogous LUR models. The best CV R(2) values for season-specific UK models predicting log(NOx) were 0.75, 0.72, and 0.74 (CV RMSE 0.20, 0.17, and 0.15) for summer, autumn, and winter, respectively. The best CV R(2) values for season-specific LUR models predicting log(NOx) were 0.74, 0.60, and 0.67 (CV RMSE 0.20, 0.20, and 0.17). The two-stage approximation to UK also performed better than LUR and nearly as well as the full UK model with CV R(2) values 0.75, 0.70, and 0.70 (CV RMSE 0.20, 0.17, and 0.17) for summer, autumn, and winter, respectively. CONCLUSION: High quality LUR and UK prediction models for NOx in Los Angeles were developed for the three seasons based on data collected for MESA Air. In our study, UK consistently outperformed LUR. Similarly, the 2-step approach was more effective than the LUR models, with performance equal to or slightly worse than UK.  相似文献   
2.
Social effectiveness constructs have been receiving increased attention in organizational research. However, the proliferation of such constructs raises questions of their relative effectiveness as predictors of job performance when used in multivariate comparison. The current study examined four social effectiveness constructs (i.e., self‐monitoring, leadership self‐efficacy, emotional intelligence and political skill) in the prediction of managerial job performance. Bivariate correlations showed that performance was predicted by social effectiveness constructs with the exception of self‐monitoring. Multiple regression analyses, using gender and seniority as control variables, found political skill to be the strongest predictor and that it has significant incremental validity in the prediction of performance over the prediction provided by the other three social effectiveness constructs as a set. Strengths and limitations of the study are discussed, as are directions for future research. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
3.
Solutions for conserving biodiversity lie in changing people's behavior. Ambitious international and national conservation policies frequently fail to effectively mitigate biodiversity loss because they rarely apply behavior-change theories. We conducted a gap analysis of conservation behavior-change interventions advocated in national conservation strategies with the Behavior Change Wheel (BCW), a comprehensive framework for systematically characterizing and designing behavior-change interventions. Using pollinator conservation as a case study, we classified the conservation actions listed in national pollinator initiatives in relation to intervention functions and policy categories of the BCW. We included all national-level policy documents from the European Union available in March 2019 that focused on conservation of pollinators (n = 8). A total of 610 pollinator conservation actions were coded using in-depth directed content analysis, resulting in the identification of 787 intervention function and 766 policy category codes. Overall, these initiatives did not employ the entire breadth of behavioral interventions. Intervention functions most frequently identified were education (23%) and environmental restructuring (19%). Least frequently identified intervention functions were incentivization (3%), and restriction (2%) and coercion were completely absent (0%). Importantly, 41% of all pollinator conservation actions failed to identify whose behavior was to be changed. Building on these analyses, we suggest that reasons for the serious implementation gap in national and international conservation policies is founded in insufficient understanding of which behavioral interventions to employ for most beneficial impacts on biodiversity and how to clearly specify the intervention targets. We recommend that policy advisors engage with behavior-change theory to design effective behavior-change interventions that underpin successful conservation policies.  相似文献   
4.
A new semiempirical approach is presented for predicting air-to-water oxygen transfer rates in mixed tanks and gravity sewers, using methods adopted from mixing theory. First, a flocculation unit was used to impart selected mean velocity gradients (G) into a completely mixed tank, from which oxygen was first removed, and dissolved oxygen concentrations were measured with time. Regression analysis was used to fit the rate of oxygen transfer equation against G. The reaeration rate in completely mixed reactors was found to be proportional to G2 (R2 = 0.987). Subsequently, G was linked to headloss in sewers, and the equation was calibrated using a slope-adjustable, 27-m-long, gravity-flow, experimental sewer (internal diameter, D = 0.16 m). Here, the reaeration rate was proportional to G1 (R2 = 0.981). The equation was compared with existing oxygen transfer models and validated against experimental data from the literature, to which the overall mass transfer coefficient for oxygen, K(L)a, derived by the new approach, conformed well.  相似文献   
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A treatablity study (TS) was conducted to evaluate the efficacy of in situ chemical oxidation (ISCO) using activated persulfate, alone and in combination with air sparging (AS), for treating a source area contaminated with residual light nonaqueous‐phase liquid (LNAPL), dissolved‐phase fuel hydrocarbons (HCs), and dissolved‐phase chlorinated alkenes at Edwards Air Force Base (AFB), California. The TS was implemented in two phases. Phase I included injecting a solution of sodium persulfate and sodium hydroxide (NaOH) into groundwater via an existing well where residual LNAPL and dissolved‐phase contaminants were present. Because the results of Phase I indicated a limited distribution of the activated persulfate, Phase II was performed to assess whether AS could enhance the distribution of the sodium persulfate. Each phase was followed by groundwater monitoring and sampling at the injection well and at three monitoring wells, located 20 to 44 feet from the injection well. Results from Phases I and II of the TS indicated that (1) alkaline‐activated persulfate was effective in promoting the dissolution of LNAPL and the degradation of dissolved‐phase contaminants, but only at the injection well; (2) the addition of AS was effective in enhancing the radius of persulfate distribution from less than 20 feet to greater than 44 feet, and (3) persulfate alone (i.e., not in an activated state) was effective in reducing the concentrations of dissolved‐phase fuel HC and chlorinated alkenes. © 2009 Wiley Periodicals, Inc.  相似文献   
7.
ABSTRACT: Major loss of life can occur in a flood when people are toppled by floodwater currents. Three approximate mechanical models and two empirical models of the hydrodynamics of toppling are presented and calibrated to align with available experimental observations to assist the analysis of the risk of life loss. The mechanical models consider circular cylindrical, square cylindrical and cylindrical composite, heavy bodies assembled to represent a human immersed in a flow field and subject to drag and buoyancy forces. The models can account for the height and weight of the exposed persons, and the velocity and depth of the flow. The models are in good mutual agreement and, when calibrated, yield failure functions that can be used to calculate the probability of loss of stability.  相似文献   
8.
The increasing alienation of people from nature is profoundly concerning because people's interactions with nature affect well-being, affinity for nature, and support of biodiversity conservation. Efforts to restore or enhance people's interactions with nature are, therefore, important to ensure sustainable human and wildlife communities, but little is known about how this can be achieved. A key factor that shapes the way people interact with nature is their affinity for nature (often measured as nature relatedness [NR]). We explored how using cues to experience nature as a means to induce NR situationally can influence the quality of people's nature interactions on visits to green spaces and their positive affect after the visit. Cues to experience are cues that guide individuals on how to interact with nature. We surveyed 1023 visitors to a nature reserve to examine the relationships between trait (i.e., stable and long-lasting) and state (i.e., temporary, brief) NR, the quality of nature interactions, and positive affect. We also conducted a controlled experiment in which 303 participants spent 30 min outdoors on campus and reported the quality of their nature interactions and positive affect. Participants were randomly assigned to 1 of 9 cues-to-experience experimental groups (e.g., smell flowers, observe wildlife, turn off your phone) that differed in the psychological distance from nature that they prompted. Participants who received cues of close psychological distance from nature (e.g., smell and touch natural elements) interacted 3 to 4 times more with nature and reported 0.2 more positive affect than other participants. Our results demonstrate that providing cues to experience nature, which bring people closer to nature and potentially induce state NR, can enhance the quality of people's nature interactions and their positive affect. These results highlight the role of NR in high-quality nature interactions and suggest the use of cues to experience as a promising avenue for inducing state NR and promoting meaningful interactions with biodiversity, thus, reconciling conservation and well-being objectives.  相似文献   
9.
Abstract

Isofenphos (Amaze®, Oftanol®, 1‐methylethyl 2‐[[ethoxy‐[(l‐methylethyl)aminol phosphinothloyl]oxy]benzoate) was applied at planting to study the effects of four different tillage treatments (no‐tillage, fall chisel plow, Paraplow®, and fall moldboard plow) on isofenphos degradation rates and routes in cornfields over two growing seasons. Soil samples were taken at intervals extending over 69 days each growing season. Tillage treatment had no significant effect on isofenphos degradation rates and products. However, the repeated application of isofenphos had a very significant effect on lsofenphos degradation. Degradation was much more rapid the second year. A laboratory experiment comparing sterile and nonsterlle soils, with and without isofenphos history, confirmed enhanced mlcrobial degradation resulting from two consecutive years of isofenphos application. In the first year, isofenphos oxon was found at greater amounts relative to the second year. Soil bioassays conducted on soils collected from the field at different dates in the second year showed that effective control of larvae was no longer present 21 days after isofenphos application in the field.  相似文献   
10.
Polyether-based polyurethanes (PBP) are extremely problematic polymers due to their long persistence in the environment. Moreover, the assessment of PBP biodegradation remains biased due to the inability of conventional methods to determine how their diverse subunits are degraded. To improve our knowledge of PBP biodegradation, we used Raman spectroscopy to identify patterns of PBP biodegradation. Specifically, PBP biodegradation was assessed using a microbial inoculum isolated from an industrial soil in which polyurethanes have been buried for 40 years. During a 28-day biodegradation assay, the PBP biodegradation level reached 27.5 % (w/w), in addition to undergoing profound alteration of the PBP composition as identified by chemical analyses. After microbial degradation, Raman analyses revealed the disappearance of the polymer’s amorphous region, which contains a high polyol content, whereas the isocyanate-rich crystalline regions were preserved. The use of Raman spectroscopy appears to be a particularly useful tool to enhance our assessment of polymer biodegradation.  相似文献   
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