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141.
Objective: Young driver studies have applied quasi-induced exposure (QIE) methods to assess relationships between demographic and behavioral factors and at-fault crash involvement, but QIE's primary assumption of representativeness has not yet been validated among young drivers. Determining whether nonresponsible young drivers in clean (i.e., only one driver is responsible) 2-vehicle crashes are reasonably representative of the general young driving population is an important step toward ensuring valid QIE use in young driver studies. We applied previously established validation methods to conduct the first study, to our knowledge, focused on validating the QIE representativeness assumption in a young driver population.

Methods: We utilized New Jersey's state crash and licensing databases (2008–2012) to examine the representativeness assumption among 17- to 20-year-old nonresponsible drivers involved in clean multivehicle crashes. It has been hypothesized that if not-at-fault drivers in clean 2-vehicle crashes are a true representation of the driving population, it would be expected that nonresponsible drivers in clean 3-or-more-vehicle crashes also represent this same driving population (Jiang and Lyles 2010 Jiang XG, Lyles RW. A review of the validity of the underlying assumptions of quasi-induced exposure. Accid Anal Prev. 2010;42:13521358.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]). Thus, we compared distributions of age, gender, and vehicle type among (1) nonresponsible young drivers in clean 2-vehicle crashes and (2) the first nonresponsible young driver in clean crashes involving 3 or more vehicles to (3) all other nonresponsible young drivers in clean crashes involving 3 or more vehicles. Distributions were compared using chi-square tests and conditional logistic regression; analyses were conducted for all young drivers and stratified by license status (intermediate vs. fully licensed drivers), crash location, and time of day of the crash.

Results: There were 41,323 nonresponsible drivers in clean 2-vehicle crashes and 6,464 nonresponsible drivers in clean 3-or-more-vehicle crashes. Overall, we found that the distributions of age, gender, and vehicle type were not statistically significantly different between the 3 groups; in each group, approximately one fourth of drivers were represented in each age from age 17 through 20, half were males, and approximately 80% were driving a car/station wagon/minivan. In general, conclusions held when we evaluated the assumption within intermediate and fully licensed young drivers separately and by crash location and time.

Conclusions: It appears that the representativeness assumption holds among the population of young NJ drivers. We encourage young driver studies utilizing QIE methods to conduct internal validation studies to ensure appropriate application of these methods and we propose utilization of QIE methods to address broader foundational and applied questions in young driver safety.  相似文献   
142.
利用浸渍焙烧法制得CeO2改性MnO2/γ-Al2O3催化剂,在常温常压下采用微波诱导氧化技术,将废水中有机污染物氧化分解。初步探讨了催化剂的制备条件,结果显示,当Ce(NO3)3浸渍浓度0.01mol/L,Mn(NO3)2浸渍浓度0.05mol/L,焙烧温度350℃,焙烧时间3h时,催化剂性能达到最佳。研究了微波辐照时间、催化剂投加量、微波功率、pH值、初始浓度等因素对甲基橙处理效果的影响。在优化条件下对甲基橙的处理效果达95%以上。  相似文献   
143.
For CO2 capture and storage (CCS) to succeed as a mitigation strategy, political commitment is one of several prerequisites. This article offers an appraisal of political commitment to a CCS strategy among high-income countries in Europe and North America: Which governments are committed, and what particular interests and concerns do they seek to accommodate by supporting CCS? In order to answer these questions, new data are reported on government CCS research, development and demonstration (RD&;D) budgets. RD&;D budgets divided by GDP is used as an indicator of political commitment, and explanations are sought for cross-national differences. The analysis shows that fossil fuels reserves and extraction within a country has a very strong bearing on funding levels. Likely explanations include the potential for combining CCS with enhanced resource recovery. All large economies (population >50 million) have a funding program. The smaller states that provide funding (Norway, Canada, the Netherlands) have the highest funding levels relative to GDP. These findings suggest that high-income petroleum producing countries are likely to be leaders in promoting CCS and a favorable regulatory environment. The fact that all large, high-income countries in the two regions now display some interest in CCS further improves its political outlook.  相似文献   
144.
草酸青霉BZH-2002果胶酶系的纯化及其诱导抗病作用   总被引:1,自引:0,他引:1  
采用超滤浓缩、亲和层析、阳离子交换柱层析、SephadexG-100凝胶过滤层析等步骤,由草酸青霉菌果胶酶发酵液最终分离得到3个电泳纯的内切聚半乳糖醛酸酶主要组分P-1、P-2和P-3.经SDS-聚丙烯酰胺凝胶电泳测得各组分的分子量(Mr)均为41×103.上述果胶酶组分稀释成不同浓度后分别喷雾处理供试黄瓜,表明3个组分均能不程度地诱导黄瓜对黑星病抗性的提高,在酶活力200UmL-1条件下,3个组分的诱导效果分别为35.18%、57.11%和38.83%,而且3个组分在试验浓度下对病菌孢子萌发和芽管生长均没有影响.图3表3参20  相似文献   
145.
The ability of many animals and insects to track a plume to its source is a particularly impressive feat when the fluid dynamics is considered. Inspired by this observation this research seeks to identify the information in a passive scalar plume suitable for developing robust and efficient plume tracing algorithms. The subject of this study is a scalar plume emanating from a point source in a turbulent boundary layer which has been modeled in a laboratory facility built specifically for this purpose. A coupled PIV-LIF technique is used to measure the velocity and scalar field in a time resolved fashion. This data set is analyzed and the convergence rates of five single-point statistics, suitable as kernels of plume tracing algorithms, are investigated. The experimental data shows that the scalar fluctuations over long downstream distances from the source are characterized by filamentary structures that lead to relatively slow convergence rates for any statistic that is based on mean concentrations. The scalar intermittency, however, converges rapidly toward its true value, in fact converging to a testable hypothesis for source location direction faster than the time scale of the larger scale plume meander.  相似文献   
146.
对黄孢原毛平革菌孢子悬浮液进行了紫外诱变,并将筛选出的优势菌ZWYB1与未经诱变的菌作对比实验,结果表明:诱变筛选得到的ZWYB1不仅可缩短对染料的脱色时间,提高对杂环类染料蕃红花红及高浓度染料400 mg/L的孔雀石绿的脱色效果,而且诱变后的菌种具有一定的脱色能力稳定性.  相似文献   
147.
对黄孢原毛平革菌孢子悬浮液进行了紫外诱变,并将筛选出的优势菌ZWYB1与未经诱变的菌作对比实验,结果表明:诱变筛选得到的ZWYB1不仅可缩短对染料的脱色时间,提高对杂环类染料蕃红花红及高浓度染料400mg/L的孔雀石绿的脱色效果,而且诱变后的菌种具有一定的脱色能力稳定性。  相似文献   
148.
The use of high resolution (10,000 resolving power) coupled gas chromatography - mass spectrometry is a well established technique in the analysis of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) but in the case of heavily contaminated stack samples interferences can still occur. A complementary technique that offers high specificity is selected reaction monitoring (SRM).A study has been made into the effects that affect the metastable dissociation of 2,3,7,8-TCDD in the first field free region (FFR1) of a magnetic sector mass spectrometer, and monitored using SRM.Monatomic, diatomic and polyatomic gases have been investigated in the collision chamber of the mass spectrometer, as have the effects of electron energy, source temperature and trap current on the dissociation, and optima conditions determined for them.  相似文献   
149.
本文通过高温烟气湿式净化特性与引风机工作原理的分析 ,论述了在高温烟气湿式净化负压系统中的引风机选配。该研究有利于高温烟气的净化和处理。  相似文献   
150.
环境执政能力已成为亚洲发展中国家的主要议题之一.政府通过立法、政策、行政和制度手段,可确保实现良好的执政.作为经济、政治和社会现代化的制度手段之一,环境咨询体系(EAS)在日本得以建立.其针对公众不断增长的对环境净化和保护的需求,增加公众参与政府决策过程的力度.强化环境执政能力的经验教训:①EAS产生的背景,即日本工业化和城市化初期几十年的环境退化和环境立法的艰难历程表明,公众对国家和地方政府的环境保护压力与日俱增.②识别了从"防治污染措施咨询委员会"(ACAP)发展到"中央环境咨询委员会"(CEAC)和"内阁全球环境委员会"(CGEC)的主要变化因素、内容和作用.ACAP主要考虑制定污染防治政策,监测、评估和补偿环境污染(如水俣病、痛痛病、呼吸道疾病等)造成的损害.CEAC和CGEC越来越多地涉及到环境保护中,包括地方、国家及全球尺度的污染预防和环境应急准备.  相似文献   
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