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461.
Objectives: This study set out to examine seat belt and child restraint use in the Dammam Municipality of the Kingdom of Saudi Arabia, based on the premise that an increase in seat belt use would significantly reduce personal injury in traffic crashes. It was expected that local data would help identify intervention strategies necessary to improve seat belt use in the region.

Methods: The research involved 2 methodologies. First, 1,389 face-to-face interviews were conducted with male and female adults in regional shopping plazas regarding their own and their children's restraint use in their vehicles and reasons for these attitudes and beliefs. Second, 2 on-road observation studies of adult and child restraint use were conducted by trained observers. Occupants of approximately 5,000 passenger vehicles were observed while stopped at representative signalized traffic intersections.

Results: The findings showed front seat belt use rates of between 43 and 47% for drivers and 26 to 30% for front seat passengers; rear seat belt use rates were lower. While there seemed to be some knowledge about the purpose and reasons for restraining both adults and children in suitable restraints, this failed to be confirmed in the on-road observations.

Conclusions: Reasons for these rates and findings are discussed fully, and recommendations for improving seat belt use in the Dammam Municipality are included.  相似文献   

462.
Objective: The number of road traffic injuries and fatalities in Iran is high. The aim of the present study was to investigate the rate of drivers' seat belt use and a number of related factors in Kashmar, Bardaskan, and Khalilabad (Iranian Safe Communities).Methods: In 2014, driver observations were made at 48 road sites on intercity roads, main streets, side streets, and rural roads in these 3 cities.Results: A total of 10,255 vehicles were observed, with the overall rate of seat belt use being 51.8%. The rates in Kashmar, Bardaskan, and Khalilabad were 51.4, 56.3, and 47.7%, respectively. In Kashmar, the odds of seat belt use were higher among drivers who were female, older, and taxi drivers. Higher use was also found during the afternoon, and lower use was observed on rural roads. In Khalilabad the odds of seat belt use were higher among females, older drivers, taxis, and private car drivers. Seat belt use was also higher on weekends and during the morning but was significantly lower on rural roads. Similarly, in Bardaskan the odds of using a seat belt were higher among females, older drivers, taxis, and private car drivers. Seat belt use was also higher during the afternoon but was significantly lower on rural roads, in comparison to main streets and intercity roads.Conclusions: The rate of seat belt use in these 3 cities was found to be low, despite these cities being designated as International Safe Communities. Therefore, seat belt promotion programs, tougher regulations, stronger enforcement, public awareness campaigns, and more research are needed to promote seat belt use in these Iranian cities.  相似文献   
463.
In recent history the volume of electronic products purchased by consumers has dramatically escalated. As a result this has produced an ever-increasing electronic waste (E-waste) stream, which has generated concerns regarding the E-waste’s potential for adversely impacting the environment. The leaching of toxic substances from obsolete personal computers (PCs) and cathode ray tubes (CRTs) of televisions and monitors, which are the most significant components in E-waste stream, was studied using landfill simulation in columns. Five columns were employed. One column served as a control which was filled with municipal solid waste (MSW), two columns were filled with a mixture of MSW and CRTs, and the other two were filled with MSW and computer components including printed wire boards, hard disc drives, floppy disc drives, CD/DVD drives, and power supply units. The leachate generated from the columns was monitored for toxic materials throughout the two-year duration of the study. Results indicate that lead (Pb) and various other heavy metals that were of environmental and health concern were not detected in the leachate from the simulators. When the samples of the solids were collected from underneath the E-waste in the columns and were analyzed, significant amount of Pb was detected. This indicates that Pb could readily leach from the E-waste, but was absorbed by the solids around the E-waste materials. While Pb was not observed in the leachate in this study, it is likely that the Pb would eventually enter the leachate after a long term transport.  相似文献   
464.
Betula papyrifera trees were exposed to elevated concentrations of CO2 (1.4 × ambient), O3 (1.2 × ambient) or CO2 + O3 at the Aspen Free-air CO2 Enrichment Experiment. The treatment effects on leaf surface characteristics were studied after nine years of tree exposure. CO2 and O3 increased epidermal cell size and reduced epidermal cell density but leaf size was not altered. Stomatal density remained unaffected, but stomatal index increased under elevated CO2. Cuticular ridges and epicuticular wax crystallites were less evident under CO2 and CO2 + O3. The increase in amorphous deposits, particularly under CO2 + O3, was associated with the appearance of elongated plate crystallites in stomatal chambers. Increased proportions of alkyl esters resulted from increased esterification of fatty acids and alcohols under elevated CO2 + O3. The combination of elevated CO2 and O3 resulted in different responses than expected under exposure to CO2 or O3 alone.  相似文献   
465.
Radiocarbon (14C) analysis of atmospheric CO2 can provide information on CO2 sources and is potentially valuable for validating inventories of fossil fuel-derived CO2 emissions to the atmosphere. We tested zeolite molecular sieve cartridges, in both field and laboratory experiments, for passively collecting atmospheric CO2. Cartridges were exposed to the free atmosphere in two configurations which controlled CO2 trapping rate, allowing collection of sufficient CO2 in between 1.5 and 10 months at current levels. 14C results for passive samples were within measurement uncertainty of samples collected using a pump-based system, showing that the method collected samples with 14C contents representative of the atmosphere. δ13C analysis confirmed that the cartridges collected representative CO2 samples, however, fractionation during passive trapping means that δ13C values need to be adjusted by an amount which we have quantified. Trapping rate was proportional to atmospheric CO2 concentration, and was not affected by exposure time unless this exceeded a threshold. Passive sampling using molecular sieve cartridges provides an easy and reliable method to collect atmospheric CO2 for 14C analysis.  相似文献   
466.
467.
This study examined the time series pattern of employment growth and stability in Fort Worth, Texas taking into account the March 28, 2000 tornado. The tornado is treated econometrically as an intervention and both the mean and conditional variance of employment growth were estimated. Overall, this regional labor market experienced a decline in the employment growth rate following the tornado. Among the sectors that exhibited differences in employment dynamics between the pre- and post-tornado periods, the mining sector experienced a significant increase in employment growth following the tornado while the service andwholesale, retail trade sectors experienced significant declines in employment growth in the post-tornado period. The manufacturing, service, and wholesale, retail trade sectors were characterized by greater stability (i.e., a lower level of employment growth volatility) in the post-tornado period than in the pre-tornado period. Interestingly, in several sectors, no differences in the time series dynamics of employment growth were detected between the pre- and post-tornado periods. These sectors included construction, finance, insurance, real estate, government, and transportation and public utilities.  相似文献   
468.
Air quality is declining in urban areas, in part because of the rapid motorization of societies world-wide. To combat the problem, various pollution control strategies have been used or proposed for urban passenger transport. This paper develops a simple framework to analyse the impact of these strategies. The paper examines the point of impact of different policy levers and categorizes different instruments in a way that should help policy makers choose between them. The framework explicitly recognizes behavioural incentives, especially the fact that offsetting changes in consumer behaviour can often undermine the original intent of particular policies. The paper concludes that policies aimed at improving transport efficiency often improve air quality at the same time. However, supply side policies to relieve traffic congestion can conflict with the objective of controlling air pollution. It is hence vital that policy makers are aware of the incentives created by different interventions and weigh the impact of these incentives on subsidiary objectives before adoption of particular policies.  相似文献   
469.
470.
Forest and agroecosystem fire management in Ghana   总被引:1,自引:0,他引:1  
The threat of wildfires to the economic potential of forestry and agriculture is one of the persistent national and international concerns. Improving and applying indigenous wildfire management (IWM) approaches is seen as one of the main hopes for mitigating and adapting to this threat to rural forest communities. Identifying the contextual causes and adaptation measures practiced by local people is essential for planning an appropriate mechanism for IWM. Yet only limited studies are available on IWM practices and most of those studies were conducted outside of this study region. To fill this gap, this study examined the wildfire mitigation and adaptation methods of forest communities in Ghana using interviews with 266 farming households. Their perceptions of the causes, cost and risk factors were also examined. The result suggests that wildfires are annual events. More than half of the wildfires reported were caused by slash-and-burn land preparation, with hunting-related fires in second place. Forest households loose about 208 Ghana cedi (US$ 231 in 2006) in value due to damaged crops and tree seedlings annually (i.e. about 50% of annual income of a Ghanaian farmer). The respondents had the operational skill and coping abilities to deal with small-scale wildfires and were supported by well-established local arrangements, community rules and silvicutural techniques. In addition, they were well informed about the basic risk factors (e.g. fuel load, climate, and presence of ignition triggers) and how these can interact to cause devastating wildfire. Therefore it is critical that policies and institutions that promote IWM initiatives build on the strong underlying community knowledge and local networks to enhance their effectiveness.  相似文献   
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