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81.
This Φ Ψ study of environmental equity uses secondary quantitative data to analyze socioeconomic disparities in environmental conditions in the Rijnmond region of the Netherlands. The disparities of selected environmental indicators—exposure to traffic noise (road, rail, and air), NO2, external safety risks, and the availability of public green space—are analyzed both separately and in combination. Not only exposures to environmental burdens (“bads”) were investigated, but also access to environmental benefits (“goods”). Additionally, we held interviews and reviewed documents to grasp the mechanisms underlying the environmental equity situation, with an emphasis on the role of public policy. Environmental equity is not a priority in public policy for the greater Rotterdam region known as the Rijnmond region, yet environmental standards have been established to provide a minimum environmental quality to all local residents. In general, environmental quality has improved in this region, and the accumulation of negative environmental outcomes (“bads”) has been limited. However, environmental standards for road traffic noise and NO2 are being exceeded, probably because of the pressure on space and the traffic intensity. We found an association of environmental “bads” with income for rail traffic noise and availability of public green space. In the absence of regulation, positive environmental outcomes (“goods”) are mainly left up to market forces. Consequently, higher-income groups generally have more access to environmental “goods” than lower-income groups.  相似文献   
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The phenomenon of the formation of two damaged xylem layers in one frost ring is described in Siberian spruce grown in western Siberian forest-tundra. Temperature conditions providing for the formation of pathological cell and tissue structures are determined. The relationship between the formation of double frost injuries and cold periods is demonstrated.  相似文献   
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This study analyzes 46 brain and 48 spinal-cord impact experiments. The velocity of brain impact was 2.0-10.0 m/s and displacement, 0.75-5.0 mm (5.3-33% compression) using a controlled pneumatic impact. The velocity of spinal-cord impact was 1.5-6.0 m/s and displacement, 1.25-3.25 mm (25-65% compression). Brain injury varied from cortical contusion, diffuse axonal injury (DAI), to fatalities, and spinal-cord injury from temporary to complete loss of somatosensory-evoked potentials. Logist functions were determined for each injury severity and various biomechanical parameters, VC, C, V, and combinations. Brain and spinal-cord injury is most strongly correlated to VC, the viscous response. The goodness-of-fit was x2 = 22.1, R-0.84 and p< 0.0000 for fatal brain injury, x2 = 27.5, R = 0.96 and p< 0.0000 for cortical contusion, and x2 = 17.7, R = 0.49 and p < 0.0001 for partial recovery of spinal-cord conduction. Neural tissue is viscoelastic, with a rate-dependent tolerance related to energy absorption. VC is a measure of energy absorption by impact deformation and is predictive of neural contusion, DAI, long-duration coma, spinal-cord dysfunction, and death. Tolerances for various severities of neural injury are presented. At the tissue level, VC is the product of strain and strain-rate, ε dε/dt. The research shows that strain is not a sufficient parameter of neural injury risk, and that the product of strain and strain-rate is a key biomechanical parameter for brain and spinal-cord injury.  相似文献   
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Traffic vehicles, many of which are powered by port fuel injection (PFI) engines, are major sources of particulate matter in the urban atmosphere. We studied particles from the emission of a commercial PFI-engine vehicle when it was running under the states of cold start, hot start, hot stabilized running, idle and acceleration, using a transmission electron microscope and an energy-dispersive X-ray detector. Results showed that the particles were mainly composed of organic, soot, and Ca-rich particles, with a small amount of S-rich and metal-containing particles, and displayed a unimodal size distribution with the peak at 600?nm. The emissions were highest under the cold start running state, followed by the hot start, hot stabilized, acceleration, and idle running states. Organic particles under the hot start and hot stabilized running states were higher than those of other running states. Soot particles were highest under the cold start running state. Under the idle running state, the relative number fraction of Ca-rich particles was high although their absolute number was low. These results indicate that PFI-engine vehicles emit substantial primary particles, which favor the formation of secondary aerosols via providing reaction sites and reaction catalysts, as well as supplying soot, organic, mineral and metal particles in the size range of the accumulation mode. In addition, the contents of Ca, P, and Zn in organic particles may serve as fingerprints for source apportionment of particles from PFI-engine vehicles.  相似文献   
85.
BACKGROUND: Most seat belt use laws originally passed in the United States contained language restricting enforcement to drivers already stopped for some other reason. States that have since removed this secondary enforcement restriction have reported increased seat belt use. The purpose of the present study was to estimate the effect of these law changes on driver fatality rates. METHOD: Trends in passenger vehicle driver death rates per billion miles traveled were compared for 10 states that changed from secondary to primary seat belt enforcement and 14 states that remained with secondary enforcement. RESULTS: After accounting for possible economic effects and other general time trends, the change from secondary to primary enforcement was found to reduce annual passenger vehicle driver death rates by an estimated 7% (95% confidence limits 3.0-10.9). CONCLUSION: The majority of U.S. states still have secondary enforcement laws. If these remaining secondary laws were amended, an estimated 696 deaths per year could be prevented.  相似文献   
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INTRODUCTION: We report the first evaluation of the popular "Cyrus the Centipede" child pedestrian safety program. METHOD: A pre-test/post-test control versus experimental condition design was used to assess Cyrus' impact on third graders' pedestrian safety knowledge, and self-reported pedestrian behaviors. RESULTS: Although some beneficial effects were observed, the program was not reliably effective. In particular, the impact of exposure to Cyrus was strongly influenced by the individual teacher who delivered it, likely due to the highly unstructured nature of the curriculum. SUMMARY: We suggest that: (a) the effectiveness and reliability of such programs be demonstrated before they are widely adopted; and (b) programs that focus on training children in actual or simulated traffic environments may be more effective than those that primarily focus on teaching safety facts and rules.  相似文献   
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Introduction: Fatal crashes that include at least one fatality of an occupant within 30 days of the crash cause large numbers of injured persons and property losses, especially when a truck is involved. Method: To better understand the underlying effects of truck-driver-related characteristics in fatal crashes, a five-year (from 2012 to 2016) dataset from the Fatality Analysis Reporting System (FARS) was used for analysis. Based on demographic attributes, driving violation behavior, crash histories, and conviction records of truck drivers, a latent class clustering analysis was applied to classify truck drivers into three groups, namely, ‘‘middle-aged and elderly drivers with low risk of driving violations and high historical crash records,” ‘‘drivers with high risk of driving violations and high historical crash records,” and ‘‘middle-aged drivers with no driving violations and conviction records.” Next, equivalent fatalities were used to scale fatal crash severities into three levels. Subsequently, a partial proportional odds (PPO) model for each driver group was developed to identify the risk factors associated with the crash severity. Results' Conclusions: The model estimation results showed that the risk factors, as well as their impacts on different driver groups, were different. Adverse weather conditions, rural areas, curved alignments, tractor-trailer units, heavier weights and various collision manners were significantly associated with the crash severities in all driver groups, whereas driving violation behaviors such as driving under the influence of alcohol or drugs, fatigue, or carelessness were significantly associated with the high-risk group only, and fewer risk factors and minor marginal effects were identified for the low-risk groups. Practical Applications: Corresponding countermeasures for specific truck driver groups are proposed. And drivers with high risk of driving violations and high historical crash records should be more concerned.  相似文献   
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