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41.
Objectives: In this study, we sought to accomplish the following objectives: to (1) calculate the percentage of children considered appropriately restrained across 8 criteria of increasing restrictiveness; (2) examine agreement between age- and size-based appropriateness criteria; (3) assess for changes in the percentage of children considered appropriately restrained by the 8 criteria between 2011 (shortly after updates to U.S. guidelines) and 2015.

Methods: Data from 2 cross-sectional surveys of 928 parents of children younger than 12 years old (n = 591 in 2011, n = 337 in 2015) were analyzed in 2017. Child age, weight, and height were measured at an emergency department visit and used to determine whether the parent-reported child passenger restraint was considered appropriate according to 8 criteria. Age-based criteria were derived from Michigan law and U.S. guidelines. Weight, height, and size-based criteria were derived from typical restraints available in the United States in 2007 and 2011. The percentage appropriate restraint use was calculated for each criterion. The kappa statistic was used to measure agreement between criteria. Change in appropriateness from 2011 to 2015 was assessed with chi-square statistics.

Results: Percentage appropriate restraint use varied from a low of 19% for higher weight limits in 2011 to a high of 91% for Michigan law in 2015. Agreement between criteria was slight to moderate. The lowest kappa was for Michigan law and higher weight limits in 2011 (κ = 0.06) and highest for U.S. guidelines and lower weight limits in 2011 (κ = 0.60). Percentage appropriate restraint use was higher in 2015 than 2011 for the following criteria: U.S. guidelines (74 vs. 58%, P < .001), lower weight (57 vs. 47%, P = .005), higher weight (25 vs. 19%, P = .03), greater height (39 vs. 26%, P < .001), and greater size (42 vs. 30%, P = .001).

Conclusions: The percentage of children considered to be using an appropriate restraint varied substantially across criteria. Aligning the definition of appropriate restraint use with current U.S. guidelines would increase consistency in reporting results from studies of child passenger safety in the United States. Potential explanations for the increased percentage of children considered appropriately restrained between 2011 and 2015 include adoption of the updated U.S. guidelines and the use of child passenger restraints with higher weight and height limits.  相似文献   
42.
生态补偿助力脱贫攻坚:协同、拮抗与对接   总被引:1,自引:1,他引:0       下载免费PDF全文
中央政府提出的“生态补偿脱贫一批”标志着生态补偿扶贫正逐步成为我国打赢脱贫攻坚战的重要途径之一。2020年是脱贫攻坚战的决胜之年,生态补偿如何有效助力脱贫攻坚成为研究的热点。本文以实践与政策为导向,运用文献研究法和逻辑分析法,在厘清生态补偿扶贫理念形成与发展的基础上,解析生态补偿与脱贫攻坚之间存在的协同效应和拮抗效应。研究发现生态补偿与脱贫攻坚在地理空间位置、实施主客体、标准、方式和途径等方面相耦合容易产生协同效应,在价值诉求、农户资源禀赋、政府部门工作等方面矛盾产生拮抗效应。生态补偿有效助力脱贫攻坚的关键在于构建对接机制以强化协同效应、弱化或去除拮抗效应。为此,通过建立精准的瞄准制度、稳定脱贫的长效机制、政府部门内部生态补偿扶贫协调机制等举措,构建生态补偿与脱贫攻坚的对接机制,以促进二者高效协同发展。  相似文献   
43.
Objective: Motor vehicle accidents, which are among the main causes of child mortality in Iran and the Middle East, impose staggering costs for the community. Ignoring use of safety devices for children in most motor vehicle crashes will lead to death or serious injury. Because few studies have been performed on effective and predictive factors regarding use of child safety seats, the purpose of this study was to examine the factors affecting the use and nonuse of child safety seats, along with the factors that can facilitate how a child safety seat is used.

Method: This study was conducted in the urban area of Gorgan using a questionnaire. Through random selection, 204 parents with at least one child, aged 8?years or younger, reported their knowledge about the benefits of using a child safety seat.

Results: The results showed that 80% of parents never use a child safety seat, and 13% always use a child safety seat. More than 93% thought that it was necessary to make usage of the child safety seat obligatory. In addition, 80% of parents believed that a child safety seat prevents children from injury in crashes. In addition, 38% of parents were not aware of child safety devices and child safety, less than 20% said that they did not use a child safety seat because their spouse did not support its use, and 28% of them thought that a child safety seat does not affect the safety of the child. In general, 91% of parents reported that if child safety seat use were mandated, the frequency of use would increase. A law on the use of child safety seats is a very important variable in their use, which can enhance the chance of using a child safety seat by 6.5 times.

Conclusion: Special instructions should be developed to create incentive strategies for using a child safety seat. Mandating the use of a child safety seat, equipping cars with a child safety seat, encouraging children to use it, and providing continuous education and training are important factors for increasing the use of child safety seats.  相似文献   
44.
Introduction: Vehicle technologies that increase seat belt use can save thousands of lives each year. Kidd, Singer, Huey, and Kerfoot (2018) found that a gearshift interlock was more effective for increasing seat belt use than an intermittent audible reminder, but interlocks may not be more effective than persistent audible reminders lasting at least 90 seconds. Method: Forty-nine part-time belt users with a recent seat belt citation who self-reported not always using a seat belt drove two vehicles for 1 week each. Thirty-three drove a Chevrolet with an intermittent audible reminder followed by either a BMW with a persistent 90-second audible reminder (n = 17) or a Subaru with an incessant audible reminder (n = 16). The other 16 participants experienced the BMW persistent reminder followed by an interlock that limited speed to 15 mph during unbelted driving. These data were combined with data from 32 part-time belt users in Kidd et al. (2018) who experienced the intermittent reminder for 2 weeks or the intermittent reminder for 1 week and a gearshift interlock the next. Results: Relative to the intermittent reminder, seat belt use was significantly increased an estimated 30% by the BMW persistent reminder, 34% by the Subaru incessant reminder, and 33% by the speed-limiting interlock. Belt use was increased an estimated 16% by the gearshift interlock, but this change was not significant. More participants circumvented the speed-limiting interlock to drive unbelted than the audible reminders. Responses to a poststudy survey indicated that interlocks were less acceptable than reminders. Conclusions: Audible reminders lasting at least 90 seconds and a speed-limiting interlock were more effective for increasing seat belt use than an intermittent audible reminder, but reminders were found more acceptable. Practical applications: Strengthening existing U.S. safety standards to require audible reminders lasting at least 90 seconds for front-row occupants could save up to 1,489 lives annually.  相似文献   
45.
高速公路绿化带对交通噪声的衰减效果研究   总被引:15,自引:0,他引:15  
公路绿化带可对交通噪声产生一定衰减作用,这对于减轻路域环境噪声污染具有重要意义。然而,针对高速公路绿化带种植树种、种植密度、林带宽度等多种因素对降噪效果影响的研究尚属空白。该研究采用选取试验点进行原位调查的方法,研究了山东省3条主要高速公路路侧绿化带对交通噪声的衰减效果,并探讨了林带宽度和郁闭度对噪声衰减的影响。研究结果表明,高速公路绿化带对交通噪声有一定的减轻作用,但在不同的绿化模式下,衰减效果存在较大差别。交通噪声的绿化衰减同林带宽度有很大关系,对于较宽林带,靠近声源前半部分的林带对噪声有较好的减轻作用,但后半部分的减噪效果较小。林带的对噪声的绿化衰减与林带宽度以及宽度和郁闭度的乘积均呈极显著的线性关系。  相似文献   
46.
Some 10 male subjects carried out a repetitive lifting task for 15 min under four conditions on separate days. Subjects used either a squat lifting or a stoop lifting technique with or without an abdominal belt on each day. Measurements of spinal shrinkage, heart rate, perceived exertion and regional body pain were made under each condition. Although there was a significant difference in spinal shrinkage under all lifting conditions compared with shrinkage during 15 min of quiet standing (4.36 ± 2.24 vs. 1.13 ± 1.18 mm), there were no significant differences in shrinkage between the conditions. The subjects' heart rates were higher during the squat lift than the stoop lift (123 vs. 97 beats/min; p < 0.001). While the squat lift was perceived to be the safest lift by 90% of the subjects, 60% regarded this lift as the least preferred method (with or without the belt). Although all 10 subjects perceived the safest lifting method to involve the use of the belt, 50% rated the belt as their least preferred lifting condition. The findings cast doubt on the efficacy and acceptability of both abdominal belts and the practice of training workers in ‘safe’ lifting techniques and indicate that individual characteristics and preferences need to be considered when attempting to improve the safety of manual handling operations in industry.  相似文献   
47.
某铁矿胶带运输机移动卸料车的除尘系统   总被引:1,自引:0,他引:1  
针对该矿胶带运输机移动卸料车定点卸料的作业特点,采用随卸料车移动的抽风罩、水平式风管接口装置及湿式除尘机组,构成简捷的除尘系统,有效地解决了卸料车作业时产生的粉尘污染问题。  相似文献   
48.
安徽沿江地区的区域发展特点与开发对策   总被引:5,自引:0,他引:5  
安徽沿江地区虽然交通网络初具规模,城市专业化分工明显经济发展水平较低,属长江干流地区的低谷地带。另外,整个沿江地区应发挥水运与矿产资源的双重优势,促使建材,钢铁,石经等临江工业进一步开并予以合理布局。  相似文献   
49.
连片特困区贫困是特殊的区域性贫困,实现持久脱贫,关键在于识别和评估区域的贫困程度以及深究其致贫原因。基于此,通过构建经济维度硬现状、社会维度软现状及自然维度潜在状态3维的多维贫困度量指标体系,应用均方差权重法测算了2006、2010及2014年秦巴集中连片特困区及各子区域的多维贫困度,并分析了多维贫困及其各维度的时空演变规律。结果表明:(1)秦巴集中连片特困区多维贫困度得分偏高,表明该区域贫困程度较深,且多维贫困在不同贫困维度上呈现显著差异。(2)2006—2014年秦巴集中连片特困区多维贫困度都呈减弱趋势,且表现出以甘肃省徽县至湖北省房县为轴带的中部地区集聚的空间演变趋势。(3)在整体多维贫困显著改善的同时,不同连片扶贫区及不同的贫困维度在减贫路径上也体现出不同的演化特征。所得结论为该区域内县域尺度贫困类型特征识别以及扶贫工作前期评估以及后期验收成效等提供一定技术支持,也为后期实施因地制宜的脱贫措施提供科学的辅助决策支撑。  相似文献   
50.
鉴于传统的输煤皮带巷雾化除尘系统不能根据煤流高度自动调节雾化程度,难以达到预期除尘效果,以同忻煤矿输煤皮带巷为研究对象,基于COMSOL Multiphysics建立了输煤皮带巷煤流扬尘模型,研究了输煤皮带巷煤流高度对粉尘运移、分布的影响,继而设计了基于超声波物位传感器等多种传感器和V形调节电动球阀联动的气水调节雾化除尘系统。结果表明:在巷道高度1.5 m以上,煤流厚度越大,同一位置处的粉尘质量浓度越大,且以呼吸性粉尘为主,同时,在巷道走向沿程上,从风流入口处至下风向30~40 m范围内,粉尘质量浓度快速增长,污染严重;全自动气水调节雾化除尘系统可使呼尘质量浓度最高下降93.57%,具有良好的可行性和应用推广性。  相似文献   
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