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91.
Objective: This study evaluated the effectiveness of a series of 1-year multifaceted school-based programs aimed at increasing booster seat use among urban children 4–7 years of age in economically disadvantaged areas.

Methods: During 4 consecutive school years, 2011–2015, the Give Kids a Boost (GKB) program was implemented in a total of 8 schools with similar demographics in Dallas County. Observational surveys were conducted at project schools before project implementation (P0), 1–4 weeks after the completion of project implementation (P1), and 4–5 months later (P2). Changes in booster seat use for the 3 time periods were compared for the 8 project and 14 comparison schools that received no intervention using a nonrandomized trial process.

The intervention included (1) train-the-trainer sessions with teachers and parents; (2) presentations about booster seat safety; (3) tailored communication to parents; (4) distribution of fact sheets/resources; (5) walk-around education; and (6) booster seat inspections.

The association between the GKB intervention and proper booster seat use was determined initially using univariate analysis. The association was also estimated using a generalized linear mixed model predicting a binomial outcome (booster seat use) for those aged 4 to 7 years, adjusted for child-level variables (age, sex, race/ethnicity) and car-level variables (vehicle type). The model incorporated the effects of clustering by site and by collection date to account for the possibility of repeated sampling.

Results: In the 8 project schools, booster seat use for children 4–7 years of age increased an average of 20.9 percentage points between P0 and P1 (P0 = 4.8%, P1 = 25.7%; odds ratio [OR] = 6.9; 95% confidence interval [CI], 5.5, 8.7; P < .001) and remained at that level in the P2 time period (P2 = 25.7%; P < .001, for P0 vs. P2) in the univariate analysis. The 14 comparison schools had minimal change in booster seat use. The multivariable model showed that children at the project schools were significantly more likely to be properly restrained in a booster seat after the intervention (OR = 2.7; 95% CI, 2.2, 3.3) compared to the P0 time period and compared to the comparison schools.

Conclusion: Despite study limitations, the GKB program was positively associated with an increase in proper booster seat use for children 4–7 years of age in school settings among diverse populations in economically disadvantaged areas. These increases persisted into the following school year in a majority of the project schools. The GKB model may be a replicable strategy to increase booster seat use among school-age children in similar urban settings.  相似文献   

92.
93.
ABSTRACT

Climate change has increased the need for clean, nonpolluting energy sources to decrease dependence on fossil fuels. Alternative energy sources, mainly solar and horizontal wind, have been the primary focus for producing clean energy. New technologies are being developed, such as the Solar Vortex (SoV), which was developed at the Georgia Institute of Technology, and relies on a vertical wind resource to generate power. The National Renewable Energy Lab (NREL) has resource models representing solar and horizontal wind resources across the 48 United States. This research developed a vertical wind resource model that is comparable in resolution to NREL’s solar and horizontal wind resource models and uses the model for estimating power output for the SoV. This model complements NREL’s existing resource models and supports the deployment of an additional clean energy generation technology. The model was applied to Mesa, Arizona to find feasible sites for a small-scale vertical wind farm.  相似文献   
94.
南京地区PM2.5污染特征及其影响因素分析   总被引:5,自引:0,他引:5  
文章利用2007年南京市草场门和迈皋桥采样点的PM2.5在线监测资料研究了南京地区PM2.5浓度的时空变化特征。对PM2.5质量浓度进行了月季变化、日变化特征分析。并利用同时期气象资料分析了PM2.5浓度与气象条件的关系。结果表明,南京市细颗粒物污染较严重,草场门采样点各月超标率均在55%以上,年超标率达72%;2采样点各季节霾天气下PM2.5质量浓度均大于非霾日下浓度均值,不管是霾天气还是非霾天气下,草场门采样点各季节PM2.5质量浓度均高于迈皋桥采样点(除秋季非霾天气)。2007年南京市PM2.5质量浓度呈现出春冬季节较高、夏秋季节较低的特点;日变化呈双峰分布。对PM2.5质量浓度与水平能见度的相关性研究表明,南京市大气能见度与细粒子质量浓度呈现很好的负相关性,相关系数高达0.98。草场门采样点霾天气下平均能见度水平仅5.2km,最高能见度为13km,最低为1.7km。  相似文献   
95.
我国柴油车的快速增长给我国柴油车污染治理带来了极大的压力,柴油车黑碳排放的研究有益于对空气质量、人体健康和气候变化采取积极的措施。研究表明,从2010年到2013年,我国柴油车增长了23%,柴油类汽车保有量约增长了约43.3%;而我国柴油车的黑碳排放量出现先增后减的趋势,2013年我国柴油机动车的黑碳排放量约为33.33万吨,比2012年减少了2.8%;河南、河北、山东、广东和内蒙五个省(自治区)柴油机动车的黑碳排放约占全国黑碳排放的37.3%。研究结果初步显示了我国柴油车污染控制的效果。  相似文献   
96.
外源锌刺激下水稻对土壤镉的累积效应   总被引:3,自引:5,他引:3  
采用水稻盆栽实验研究不同含量外源Zn对模拟Cd中度污染和重度污染土壤中水稻低累积品种湘晚籼12和高累积品种威优46水稻各部位累积Cd的影响.结果表明,在Cd中度污染水平,外源Zn分别增大2种水稻各部位Cd含量,湘晚籼12和威优46糙米Cd含量分别增加125.0%~275.0%和6.6%~91.2%,但各处理糙米Cd含量不高于0.2 mg·kg~(-1);在Cd重度污染水平,外源Zn有降低水稻各部位中Cd含量的作用,湘晚籼12和威优46糙米Cd含量相应降低了16.6%~63.5%和15.6%~74.4%,且威优46糙米Cd含量随外源Zn施用含量的增大而逐渐降低,使得糙米中Cd含量低于0.2 mg·kg~(-1).水稻糙米累积Cd含量与土壤中Cd、Zn交换态含量的相关关系,因Cd污染程度和水稻品种的不同而不同.在Cd中度污染水平,湘晚籼12水稻糙米Cd含量与土壤中交换态Zn含量正线性相关,而威优46水稻糙米Cd含量与土壤中交换态Cd和Zn含量正线性相关;在Cd重度污染水平,威优46水稻糙米Cd含量与土壤中交换态Cd和Zn含量为负线性相关.在不造成土壤Zn污染的前提下,可向Cd重度污染土壤施用一定量的Zn肥,以降低糙米Cd含量,提高糙米品质.  相似文献   
97.
污染源水质COD在线仪器比对监测   总被引:2,自引:0,他引:2  
比较了几种现场应用较多的水质COD在线监测分析与实验室分析方法在原理、方法等方面的主要差异,针对比对过程中存在的实际问题,提出了在样品采集、仪器原理选择、仪器定期校正等方面做好水质COD在线监测比对实验工作的建议。  相似文献   
98.
吴赛苏  王静  洪英 《干旱环境监测》2001,15(2):73-73,76
在硼砂 -氢氧化钠缓冲溶液 (p H=1 1 .0 )中 ,溴化十六烷基三甲胺 (CTMAB)存在下双硫腙与锌生成可溶于水的 2∶ 1红色络合物 ,λmax=540 nm ,ε=7.3 0× 1 0 4 L· cm-1· mol-1,锌含量在 0~ 0 .6mg/L内符合比耳定律。本法可用于水样中锌含量的测定  相似文献   
99.
Science, politics and environmental policy have for several years been encountering social and institutional as well as scientific challenges, national and international. The normative basis of all sciences is pressurised from three sides: by awareness of the public, who claims more transparency and sensibility from the scientific institutions regarding factual or possible impacts of science-based industrial progress; by the industries, which try to speed up and intensify the industrialisation of knowledge; and by the public policies, which want to see the sciences engaged in ways to mitigate unintended consequences of economic, ecological and social developments. At the same time, environmental policy is undergoing a tremendous sea change both in conceptual and practical matters. Since the Brundtland Report in 1987 and accelerated after UNCED 1992, environmental policy has been struggling to become a groundbreaking new paradigm for the capacity of resolving social and political issues as well. Any successful attempt to alter traditional institutional and mental structures in policy-making toward sustainability presupposes a renewed association of co-operation, deliberation and decision making. Results from theory of democracy, studies in science and technology, and evaluation studies in environmental policy and politics can be utilised for this context.  相似文献   
100.
为了研究土-结构相互作用(SSI)对设置金属阻尼器框架结构的影响规律,本文设计实现了考虑SSI 的设置开孔式加劲阻尼器体系的框架结构振动台模型试验。试验采用层状剪切盒模拟土体的边界,锯末和砂土的混合物作为地基土,以12 层钢筋混凝土框架结构模拟上部结构。基础采用3×3 群桩基础。本文完成了1:6 比例的高层结构—桩—土动力相互作用体系(PSSI)、设置金属阻尼器的PSSI 体系以及刚性地基上框架结构和刚性地基上设置金属阻尼器的框架结构共4 个模型振动台试验。从动力特性、地震响应等方面对比分析了纯框架与消能减震结构的差别。并通过计算减震率,分析了SSI 效应对消能减震结构减震效果的影响规律。结果表明:消能减震结构在同样的地震作用加载下,频率衰减幅度降低为纯框架的1/3~1/2,阻尼比增加幅度为纯框架的1/2 左右,结构的损伤程度明显减弱,阻尼器起到了显著的减震效果。SSI 体系消能减震结构的阻尼器减震效率下降,但SSI 的减震效果加强,综合来看,其减震率依然高于刚性地基结构。  相似文献   
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