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111.
Objective: The aim of this study is to develop an on-scene injury severity prediction (OSISP) algorithm for truck occupants using only accident characteristics that are feasible to assess at the scene of the accident. The purpose of developing this algorithm is to use it as a basis for a field triage tool used in traffic accidents involving trucks. In addition, the model can be valuable for recognizing important factors for improving triage protocols used in Sweden and possibly in other countries with similar traffic environments and prehospital procedures.

Methods: The scope is adult truck occupants involved in traffic accidents on Swedish public roads registered in the Swedish Traffic Accident Data Acquisition (STRADA) database for calendar years 2003 to 2013. STRADA contains information reported by the police and medical data on injured road users treated at emergency hospitals. Using data from STRADA, 2 OSISP multivariate logistic regression models for deriving the probability of severe injury (defined here as having an Injury Severity Score [ISS] > 15) were implemented for light and heavy trucks; that is, trucks with weight up to 3,500 kg and ??16,500 kg, respectively. A 10-fold cross-validation procedure was used to estimate the performance of the OSISP algorithm in terms of the area under the receiver operating characteristic curve (AUC).

Results: The rate of belt use was low, especially for heavy truck occupants. The OSISP models developed for light and heavy trucks achieved cross-validation AUC of 0.81 and 0.74, respectively. The AUC values obtained when the models were evaluated on all data without cross-validation were 0.87 for both light and heavy trucks. The difference in the AUC values with and without use of cross-validation indicates overfitting of the model, which may be a consequence of relatively small data sets. Belt use stands out as the most valuable predictor in both types of trucks; accident type and age are important predictors for light trucks.

Conclusions: The OSISP models achieve good discriminating capability for light truck occupants and a reasonable performance for heavy truck occupants. The prediction accuracy may be increased by acquiring more data. Belt use was the strongest predictor of severe injury for both light and heavy truck occupants. There is a need for behavior-based safety programs and/or other means to encourage truck occupants to always wear a seat belt.  相似文献   
112.
This paper examines whether foreign aid, together with other economic, social and environmental factors, contributes to sustainable development. It starts with an illustrative theoretical growth model where foreign aid promotes sustainable development by protecting the environment. Using factor analysis and newly developed estimation methods for a dynamic panel data model with endogenous regressors, the empirical section of the paper finds evidence that foreign aid has had a significantly positive influence on sustainable development in aid recipient countries. This effect is very likely to go through channels related to growth and resources as well as a technology channel with respect to energy intensity. This research has important implications for a post‐2015 development framework on international collective action with regard to a sustainable future.  相似文献   
113.
Yi Lu  Jiuping Xu 《Disasters》2015,39(2):258-278
The number of communities affected by disasters has been rising. As a result, non‐governmental organisations (NGOs) that attend community post‐disaster reconstruction are often unable to deliver all requirements and have to develop cooperative approaches. However, this collaboration can cause problems because of the complex environments, the fight for limited resources and uncoordinated management, all of which result in poor service delivery to the communities, adding to their woes. From extensive field research and case studies conducted in the post‐Wenchuan earthquake‐stricken communities, this paper introduces an integrated collaboration framework for community post‐disaster reconstruction with the focus on three types of NGOs: international, government organised and civil. The proposed collaboration framework examines the three interrelated components of organisational structure, operational processes and reconstruction goals/implementation areas. Of great significance in better promoting collaborative participation between NGOs are the crucial concepts of participatory reconstruction, double‐layer collaborative networks, and circular review and revision.  相似文献   
114.
采用一种新型的多级A/O膜生物反应器处理污水,对该工艺的污泥活性进行了研究。结果表明,VSS/SS在实验过程中呈较弱的下降趋势,多级A/O池曝气室污泥比硝化速率逐室下降,但各缺氧室污泥比反硝化速率基本一致;污泥释磷、聚磷过程在30 min和1 h内基本完成,反硝化聚磷试验表明污泥中存在DPB的富集,反硝化作用是反硝化细菌与DPB共同作用的结果。  相似文献   
115.
研究了固相膜萃取对地表水中有机氯农药(OCPs)物质的提取效果,并与液液提取法(LLE)进行比较.建立了固相膜萃取/气相色谱法检测地表水中20种有机氯农药的方法.结果表明:当萃取膜为HLB膜,洗脱液溶剂为丙酮和正己烷,萃取效果最理想,20种OCPs的回收率稳定在74.1%~94.3%之间,固相膜萃取法与传统液液提取法相比,既提高了萃取效率同时又减少了有机萃取溶剂的用量.该法检测实际样品时,同时加入2种内标指示剂对方法的性能进行了验证,2种内标示踪剂的回收率分别为71.6%~94.8%和69.9%~109.5%,样品中20种OCPs均未检出.  相似文献   
116.
基于碳中和背景及污水处理可持续、低碳运行理念,分析了我国污水处理厂不同水质、工艺类型、规模等条件下的能源消耗及能源回收特点,提出了以“碳改向技术+低耗高效复合脱氮技术+污泥厌氧共消化技术+污水热能回收技术+节能降耗技术”的污水处理新模式是实现我国能源自给型污水处理厂的关键,并提出我国污水处理厂实现碳中和应分为“完全能源自给”及“能源供应工厂”两个目标.此外,对基于此背景下建设的北京某再生水厂的理论能源自给情况进行了分析,结果表明,通过节能降耗、引入外源有机物、污水源热泵回收等措施,北京某再生水厂能源自给率由12.2%分别提高至17.1%、21.6%、84.7%.  相似文献   
117.
不同磁黄铁矿自养反硝化脱氮除磷作用   总被引:1,自引:0,他引:1  
氮磷排放标准日趋严格,开发高效廉价脱氮除磷材料已成为研究热点.采用黄铁矿与赤铁矿在管式炉中氮气气氛下600 ℃煅烧,得到硫化赤铁矿形成的磁黄铁矿、黄铁矿热分解形成的磁黄铁矿,构建磁黄铁矿-方解石体系处理含氮磷模拟废水,对比不同方式制备的磁黄铁矿、天然磁黄铁矿、黄铁矿、硫磺脱氮除磷性能,考察不同磁黄铁矿晶体结构和结晶度差异及其对脱氮除磷影响,探究不同体系中矿物结构和微生物群落变化.结果表明:黄铁矿热分解产物以六方磁黄铁矿为主;硫化赤铁矿产物以低结晶度的单斜磁黄铁矿为主,因而表现出优异的脱氮除磷活性,氮磷去除率分别为99.8%和96.8%.铁硫化物与微生物反应产物的XRD、SEM和FE-TEM分析结果表明,微生物能有效利用磁黄铁矿进行脱氮,磷酸盐主要以FePO4形式被去除.群落分析结果表明铁硫化物脱氮除磷体系中的主要功能菌属为Thiobacillus Sulfurimonas,结晶度低的单斜磁黄铁矿更有利于Thiobacillus定向富集.  相似文献   
118.
采用包埋固定化技术制备了包埋硫铁生物填料(ESI Filler),基于升流式自养反硝化反应器开展动态实验研究,通过改变水力停留时间(HRT)、pH值、溶解氧(DO)等运行条件,探究ESI Filler反应器的脱氮效果及微生物群落结构组成。结果表明,当进水硝酸盐氮(NO3--N)浓度为30mg/L,HRT为10h时,NO3--N去除率不断上升至99.80%。当HRT缩短为2.5h时,NO3--N去除率降至61.35%。ESI Filler反应器对pH值和DO的改变具有较高的稳定性,NO3--N平去除率可维持在82.5%以上。但对低温的耐受性较差,当温度从35℃降低至15℃时,NO3--N平均去除率由90.12%降低至68.80%。运行164d后,球体未出现破裂散落的现象,表现出较长的使用寿命。通过扫描电镜发现,填料表面疏松多孔,附着大量杆状细菌,已成为微生物的良好载体。高通量测序结果表明,包埋颗粒中优势菌属为典型的自养反硝化功能菌Thiobacillus,丰度为80.79%。  相似文献   
119.
Creating False Images: Stream Restoration in an Urban Setting   总被引:1,自引:0,他引:1  
Stream restoration has become a multibillion dollar business with mixed results as to its efficacy. This case study utilizes pre‐ and post‐monitoring data from restoration projects on an urban stream to assess how well stream conditions, publicly stated project goals, and project implementation align. Our research confirms previous studies showing little communication among academic researchers and restoration practitioners as well as provides further evidence that restoration efforts tend to focus on small‐scale, specific sites without considering broader land use patterns. This study advances our understanding of restoration by documenting that although improving ecological conditions is a stated goal for restoration projects, the implemented measures are not always focused on those issues that are the most ecologically salient. What these projects have accomplished is to protect the built environment and promote positive public perception. We argue that these disconnects among publicized goals for restoration, the implemented features, and actual stream conditions may create a false image of what an ecologically stable stream looks like and therefore perpetuate a false sense of optimism about the feasibility of restoring urban streams.  相似文献   
120.
运用正交设计方法对SPME-GC法测试三氯乙烯、四氯乙烯的固相微萃取条件进行优化。首先选择样品量、NaCl用量、萃取温度、萃取时间、解析温度等因素,设计5因素3水平正交试验方案。分析数据得到优化条件为NaCl用量30 g/L,萃取温度25℃,解析温度210℃,同时得出样品量与萃取时间是对试验结果具有显著意义的影响因素,采用二次回归正交组合设计试验对其进一步优化,并对结果进行回归分析,得到最优条件为样品量为5.5 mL,萃取时间为20.13 min。  相似文献   
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