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661.
Disaster waste management: a review article   总被引:1,自引:0,他引:1  
Depending on their nature and severity, disasters can create large volumes of debris and waste. The waste can overwhelm existing solid waste management facilities and impact on other emergency response and recovery activities. If poorly managed, the waste can have significant environmental and public health impacts and can affect the overall recovery process.This paper presents a system overview of disaster waste management based on existing literature. The main literature available to date comprises disaster waste management plans or guidelines and isolated case studies. There is ample discussion on technical management options such as temporary storage sites, recycling, disposal, etc.; however, there is little or no guidance on how these various management options are selected post-disaster. The literature does not specifically address the impact or appropriateness of existing legislation, organisational structures and funding mechanisms on disaster waste management programmes, nor does it satisfactorily cover the social impact of disaster waste management programmes.It is envisaged that the discussion presented in this paper, and the literature gaps identified, will form a basis for future comprehensive and cohesive research on disaster waste management. In turn, research will lead to better preparedness and response to disaster waste management problems.  相似文献   
662.
Objective: Traffic crashes have high mortality and morbidity for young children. Though many specialized child restraint systems improve injury outcomes, no large-scale studies have investigated the cross-chest clip's role during a crash, despite concerns in some jurisdictions about the potential for neck contact injuries from the clips. This study aimed to investigate the relationship between cross-chest clip use and injury outcomes in children between 0 and 4 years of age.

Methods: Child passengers between 0 and 4 years of age were selected from the NASS-CDS data sets (2003–2014). Multiple regression analysis was used to model injury outcomes while controlling for age, crash severity, crash direction, and restraint type. The primary outcomes were overall Abbreviated Injury Score (AIS) 2+ injury, and the presence of any neck injury.

Results: Across all children aged 0–4 years, correct chest clip use was associated with decreased Abbreviated Injury Scale (AIS) 2+ injury (odds ratio [OR] = 0.44, 95% confidence interval [CI], 0.21–0.91) and was not associated with neck injury. However, outcomes varied by age. In children <12 months old, chest clip use was associated with decreased AIS 2+ injury (OR = 0.09, 95% CI, 0.02–0.44). Neck injury (n = 7, all AIS 1) for this age group only occurred with correct cross-chest clip use. For 1- to 4-year-old children, cross-chest clip use had no association with AIS 2+ injury, and correct use significantly decreased the odds of neck injury (OR = 0.49; 95% CI, 0.27–0.87) compared to an incorrectly used or absent cross-chest clip. No serious injuries were directly caused by the chest clips.

Conclusions: Correct cross-chest clip use appeared to reduce injury in crashes, and there was no evidence of serious clip-induced injury in children in 5-point harness restraints.  相似文献   

663.
Objectives: In a pilot randomized controlled trial of contingency management (CM) and transdermal alcohol monitoring (TAM) with offenders driving while impaired by alcohol (DWI), perceptions regarding the acceptability of a TAM device, recruitment issues, and the impact of CM and TAM on alcohol use over a 6-week period were evaluated. The results aimed to inform the design of future trials and programs involving CM and TAM for DWI remediation.

Methods: TAM devices were affixed to 37 voluntary, community-recruited male DWI offenders with problem alcohol use. They were randomized to one of 3 groups: (1) CM; (2) alcohol use feedback (FB); and (3) TAM device only (CTL). Quantitative and qualitative data were gathered on the acceptability of TAM devices and recruitment, and alcohol use was monitored via TAM and self-report.

Results: The TAM device was perceived positively, with benefits for reducing drinking noted. Nevertheless, some of its inconveniences appeared to influence participant recruitment and attrition, including its large size and limited water resistance. TAM data revealed a significant main effect of time for reduction in weekly peak transdermal alcohol concentration (P = .02), with a decrease between means of weeks 1 and 6 (M = 0.15, SE = 0.02 vs. M = 0.09, SE = 0.02; P = .005). No significant group effect was detected.

Conclusions: TAM is a viable adjunct to CM with DWI offenders, though the TAM device used here may influence both study recruitment and adherence. These findings can guide the design of future studies into CM and TAM for DWI remediation.  相似文献   

664.
Kurt Lewin and others have showed that group discussion effectively changed attitudes and behaviors compared to individually targeted messages. This study examines the roles of normative and informational social influence in this effect. High school students heard a message about replacing toxic products with nontoxic alternatives; classes were randomly assigned to hear the message delivered as a lecture or via guided group discussion. For female students (N=250 in 26 classes), HLM mediation analyses suggested normative influence predominated: Discussion was more effective than lecture and this effect was fully mediated by students’ perceptions that other students endorsed nontoxics. Content analyses of students’ comments indicated that three kinds of remarks led female students to this perception: (1) sharing knowledge about nontoxics; (2) asking questions about nontoxics; and (3) little praise for toxic products. For male students in separate HLM analyses (N=107 in 19 of the same classes), informational influence was most apparent: Postmeeting attitudes were higher after discussion than lecture, and this effect was partially mediated by cognitive elaboration about the message (but not perceptions others endorsed the message). In addition, males’ quiz grades were higher after discussion, and students’ comments fully mediated the discussion to quiz grades relationship. Results support the importance of hearing others’ promessage comments for changing socially motivated behaviors, although the routes of influence appear to differ for these samples of male and female students.  相似文献   
665.
In urban and suburban areas, stormwater runoff is a primary stressor on surface waters. Conventional urban stormwater drainage systems often route runoff directly to streams and rivers, thus exacerbating pollutant inputs and hydrologic disturbance, and resulting in the degradation of ecosystem structure and function. Decentralized stormwater management tools, such as low impact development (LID) or water sensitive urban design (WSUD), may offer a more sustainable solution to stormwater management if implemented at a watershed scale. These tools are designed to pond, infiltrate, and harvest water at the source, encouraging evaporation, evapotranspiration, groundwater recharge, and re-use of stormwater. While there are numerous demonstrations of WSUD practices, there are few examples of widespread implementation at a watershed scale with the explicit objective of protecting or restoring a receiving stream. This article identifies seven major impediments to sustainable urban stormwater management: (1) uncertainties in performance and cost, (2) insufficient engineering standards and guidelines, (3) fragmented responsibilities, (4) lack of institutional capacity, (5) lack of legislative mandate, (6) lack of funding and effective market incentives, and (7) resistance to change. By comparing experiences from Australia and the United States, two developed countries with existing conventional stormwater infrastructure and escalating stream ecosystem degradation, we highlight challenges facing sustainable urban stormwater management and offer several examples of successful, regional WSUD implementation. We conclude by identifying solutions to each of the seven impediments that, when employed separately or in combination, should encourage widespread implementation of WSUD with watershed-based goals to protect human health and safety, and stream ecosystems.  相似文献   
666.
Characterization of particulate matter for three sites in Kuwait   总被引:1,自引:0,他引:1  
Many studies have shown strong associations between particulate matter (PM) levels and a variety of health outcomes, leading to changes in air quality standards in many regions, especially the United States and Europe. Kuwait, a desert country located on the Persian Gulf, has a large petroleum industry with associated industrial and urban land uses. It was marked by environmental destruction from the 1990 Iraqi invasion and subsequent oil fires. A detailed particle characterization study was conducted over 12 months in 2004-2005 at three sites simultaneously with an additional 6 months at one of the sites. Two sites were in urban areas (central and southern) and one in a remote desert location (northern). This paper reports the concentrations of particles less than 10 microm in diameter (PM10) and fine PM (PM2.5), as well as fine particle nitrate, sulfate, elemental carbon (EC), organic carbon (OC), and elements measured at the three sites. Mean annual concentrations for PM10 ranged from 66 to 93 microg/m3 across the three sites, exceeding the World Health Organization (WHO) air quality guidelines for PM10 of 20 microg/m3. The arithmetic mean PM2.5 concentrations varied from 38 and 37 microg/m3 at the central and southern sites, respectively, to 31 microg/m3 at the northern site. All sites had mean PM2.5 concentrations more than double the U.S. National Ambient Air Quality Standard (NAAQS) for PM2.5. Coarse particles comprised 50-60% of PM10. The high levels of PM10 and large fraction of coarse particles comprising PM10 are partially explained by the resuspension of dust and soil from the desert crust. However, EC, OC, and most of the elements were significantly higher at the urbanized sites, compared with the more remote northern site, indicating significant pollutant contributions from local mobile and stationary sources. The particulate levels in this study are high enough to generate substantial health impacts and present opportunities for improving public health by reducing airborne PM.  相似文献   
667.
668.
本文根据辐射传热和对流传热理论,利用Matlab 程序结合太阳能热水器本身的尺寸以及与其有关的水和空气的物理弹性详细分析了影响平板式太阳能热水器热效率的因素包括太阳能热水器表面的太阳光辐射的吸收率αs 和辐射系数ε,太阳能热水器的水进口温度Tc,in和流量mc 太阳辐射能力Gs,,环境大气温度Te,大气辐射系数εsky 以及太阳能热水器内部的总传热系数U。分析结果表明较高的太阳照射能力、环境温度和总传热系数有利于提高集热效率,而增加水量和水进口温度、热水器辐射系数和大气辐射系数则有相反的效果。  相似文献   
669.
Mating systems and sexual selection are assumed to be affected by the distribution of critical resources. We use observations of 312 mating aggregations to compare mate-searching success of male northern water snakes (Nerodia sipedon) in two marshes in which differences in mating substrate availability resulted in more than fourfold differences in female dispersion. Reproductive males had significantly larger home ranges where females were dispersed than where females were clumped. The number of females encountered by males increased significantly with male home range size where females were dispersed, and decreased significantly where females were clumped. Where females were clumped, males were more likely to encounter other males when they located females. We found no evidence in either population that mate searching was energetically expensive or that males with relatively more energy had larger home ranges. However, males with greater fat reserves at the start of the season participated in more mating aggregations when females were dispersed, suggesting that fat reserves could affect a male’s willingness to attempt mating or to persist in aggregations. When females were dispersed there was weak stabilizing selection acting to maintain male body size (β=–0.14), but strong directional selection favoring larger (β=0.50) and fatter (β=0.37) males. Over 7 years, the intensity of selection favoring larger males varied substantially (β=0.14–1.15), but that variation was not related to variation in the operational sex ratio. We found no evidence of directional selection on either body size (β=0.05) or fat reserves (β=0.10) of males when females were spatially clumped. Overall, the distribution of females had a pronounced effect on male behavior, on the factors that affected male success in locating females, and probably on the extent of sperm competition once females had been located. Received: 23 November 1998 / Received in revised form: 9 August 1999 / Accepted: 18 August 1999  相似文献   
670.
Abstract: The endangered grassland daisy Rutidosis leptorrhynchoides has been subject to severe habitat destruction and fragmentation over the past century. Using allozyme markers, we examined the genetic diversity and structure of 16 fragmented populations. The species had high genetic variation compared to other plant species, and both polymorphism and allelic richness showed strong positive relationships with log reproductive population size, reflecting a loss of rare alleles (frequency of q < 0.1) in smaller populations. Fixation coefficients were positively related to size, due either to a lack of rare homozygotes in small populations or to Wahlund effects (owing to spatial genetic structure) in large ones. Neither gene diversity nor heterozygosity was related to population size, and other population parameters such as density, spatial contagion, and isolation had no apparent effect on genetic variation. Genetic divergence among populations was low , despite a large north-to-south break in the species' current distribution. To preserve maximum genetic variation, conservation strategies should aim to maintain the five populations larger than 5000 reproductive plants, all of which occur in the north of the range, as well as the largest southern population of 626 plants at Truganina. Only one of these is currently under formal protection. High heterozygosity in smaller populations suggests that they are unlikely to be suffering from inbreeding depression and so are also valuable for conservation. Erosion of allelic richness at self-incompatibility loci, however, may limit the reproductive capacity of populations numbering less than 20 flowering plants.  相似文献   
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