Intersection AEB implementation strategies for left turn across path crashes

Abstract

Objective: Left turn across path with traffic from the opposite direction (LTAP/OD) is the second most frequent car-to-car intersection crash type after straight crossing path (SCP) in Germany and the United States. Intersection automated emergency braking (AEB) for passenger cars can address these crashes.

This study investigates 2 implementation strategies of intersection AEB addressing LTAP/OD crashes: (1) only the turning car is equipped with an intersection AEB and (2) turning and straight-heading cars are equipped with an intersection AEB. For each strategy, the influence of a safety zone around the vehicles that should not be entered is evaluated in terms of accident avoidance, injury mitigation, and change in velocity (delta-V) of remaining accidents. Results are given as a function of market penetration.

Methods: A total of 372 LTAP/OD crashes from the time series precrash matrix (PCM), a subsample of the German In-Depth Accident Study (GIDAS), were resimulated in the PRediction of Accident Evolution by Diversification of Influence factors in COmputer simulation (PRAEDICO) simulation framework. A Kudlich-Slibar rigid-body impact model and an injury risk curve derived from GIDAS were used to predict remaining moderate to fatal (Maximum Abbreviated Injury Scale [MAIS] 2?+?F) injuries among car occupants.

Results: With a safety zone of 0.2 m, when the turning vehicle only was equipped with an intersection AEB, 59% of the crashes were avoided at a 100% market penetration. With both vehicles equipped the percentage increased to 77%. MAIS 2?+?F injured occupants were reduced by 60 and 76%, respectively. Considering both the turning and the straight-heading vehicles, the delta-V decreased strongly with market penetration in remaining left-side impacts but only slightly in remaining frontal and right-side impacts. Eliminating the safety zone substantially decreases effectiveness in all conditions.

Conclusions: Implementation strategy and safety zone definition strongly influence the real-life performance of intersection AEB. AEB should be applied not only for the turning vehicle but also for the straight-going vehicle to benefit from the full potential. Situationally appropriate safety zone definitions, in line with human hazard perception, need more attention and are a key to balance true positive and false positive performance. Remaining delta-V does not decrease broadly; hence, there is no evidence that future LTAP/OD crashes will be generally of lower severity. This highlights the need for continuous development of in-crash protection.     

Motorcycle helmet visor–related facial injury and its potential mechanism of injury: Evidence-based case study

Objectives: We encountered an unusual facial laceration wound in relation to motorcycle helmet visor use during our clinical practice. We aimed to assess the prevalence of this unusual facial injury among motorcyclists who sustained facial injuries in selected hospitals and to determine the possible mechanism involved.

Methods: We used our prospective cross-sectional substudy involving injured motorcyclists presenting at major trauma hospitals in Southern Klang Valley, Malaysia, between March 2010 and March 2011. of 391 subjects with facial injuries, 2 male motorcyclists sustained this laceration. The wounds were assessed and we believed that each was associated with the helmet visor. One of the visors was collected and the edge was inspected using scanning electron microscopy (SEM).

Results: The prevalence of this unusual injury was 0.51% (95% confidence interval, 0.002–0.012) among motorcyclists who sustained facial injuries. Both cases were involved in a head-on collision with their colliding partners and their helmets were intact throughout the crash. The visor in case 1 was intact, but the visor in case 2 was broken. SEM analysis showed that the visor in case 1 had a potential cutting surface.

We postulated that with helmet rotation in the forward and downward position and with some degree of visor bending or with a dislodged visor, the sharp-edged visor could potentially severely lacerate the face.

Conclusion: This injury affects facial aesthetics and early referral to the facial surgery team is advocated. Documentation of the mechanism of injury, the patient’s helmet and visor is obligatory, so that this information can be delivered to the regional road safety authority for preventive measures.     

Population-based assessment of a vehicle fleet with seat belts providing lower shoulder belt forces than today

Objective: The objective of this study was to quantify the population-based effects of a lower shoulder belt load limit on front row occupants in frontal car crashes.

Method: Crashes of modern vehicles from the GIDAS (German In-Depth Accident Study) are corrected for bias and projected to the national level. Injury risk functions are computed for the injury severity levels Maximum Abbreviated Injury Scale (MAIS) 2+, MAIS 3+, and fatal, stratified by 2 age cohorts (16–44 years of age and 45 years or older). To assess the field effectivity of a “softer belt,” the projected crash frequency data are modified separately for the 2 age cohorts such that its risk structure represents the risk of a softer belt. Given those 2 samples, the field effectivity of a softer belt is derived for several shares of the younger age cohort according to the injury severity levels MAIS 2+, MAIS 3+, and fatal.

Results: The injury risk distribution of the projected crash frequency data, represented here by the injury risk functions obtained, fits well into the injury risk distribution of other data sets (Sweden, United States, and Japan) given in the literature. The relative effects of a lower belt force are stable over the different ratios of the younger and old age cohorts. At the MAIS 2+ level, a lower belt force can significantly reduce the number of injuries (about 10%). A lower belt force does not significantly affect the number of MAIS 3+ injuries. A lower belt force can, however, more than double the number of fatal injuries.

Conclusions: Because the number of fatal injuries rises dramatically due to lower belt force, the reduction in the number of MAIS 2+ injuries comes at a very high cost. Therefore, whether reducing the belt force limit is the right approach is questionable.     

La对Pb伤害大豆幼苗的影响

以盆载法研究了Ｐｂ对大豆幼苗的伤害及Ｌａ对Ｐｂ伤害的生态生理效应．结果显示,１０００ｍｇＬ－１ＰｂＡｃ２能严重抑制大豆幼苗代谢与生长,叶面喷布３０ｍｇＬ－１ＬａＣｌ３１次,能减轻Ｐｂ造成的毒害．实验证明,此与Ｌａ能增加大豆幼苗光合速率,提高叶绿素含量与硝酸还原酶活性,降低细胞质膜透性与体内Ｐｂ含量,维持ＴＴＣ还原力等多种作用相关     

Tibouchina pulchra (Cham.) Cogn., a native Atlantic Forest species, as a bio-indicator of ozone: visible injury

Tibouchina pulchra saplings were exposed to carbon filtered air (CF), ambient non-filtered air (NF) and ambient non-filtered air+40 ppb ozone (NF+O3) 8 h per day during two months. The AOT40 values at the end of the experiment were 48, 910 and 12,895 ppb h(-1), respectively, for the three treatments. After 25 days of exposure (AOT40=3871 ppb h(-1)), interveinal red stippling appeared in plants in the NF+O3 chamber. In the NF chamber, symptoms were observed only after 60 days of exposure (AOT40=910 ppb h(-1)). After 60 days, injured leaves per plant corresponded to 19% in NF+O3 and 1% in the NF treatment; and the average leaf area injured was 7% within the NF+O3 and 0.2% within the NF treatment. The extent of leaf area injured (leaf injury index) was mostly explained by the accumulated exposure of ozone (r2=0.89; p<0.05).     

汽车尾气暴露对小鼠运动力竭时间的影响

汽车尾气是城市中大气污染物的主要来源,为探究汽车尾气对机体的损伤作用及其机制,通过建立汽车尾气暴露动物模型,利用轮式疲劳仪评估汽车尾气对小鼠运动力竭时间的影响。结果表明,汽车尾气连续暴露30 d后,暴露组小鼠的运动力竭时间较正常对照组明显缩短,支气管-肺泡灌洗液(BALF)中细胞因子白介素-1β(IL-1β),白介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)水平较正常对照组明显升高,血清中谷胱甘肽(GSH)和超氧化物歧化酶(SOD)活性明显降低,丙二醛(MDA)含量显著升高。汽车尾气长时间暴露组(8 h·d-1)BALF中白细胞计数和中性粒细胞百分比较正常对照组明显升高。肺组织切片染色后可见汽车尾气长时间暴露组小鼠肺泡间质中有较多中性粒细胞及淋巴细胞浸润。上述研究结果表明,汽车尾气可能通过引起呼吸系统损伤和降低机体抗氧化应激能力减少小鼠的运动力竭时间。     

氟对中华圆田螺肝胰脏抗氧化酶和MDA的影响

选取中华圆田螺为受试动物,探究氟对其肝胰脏抗氧化酶SOD、GSH、POD活性和丙二醛MDA含量的影响。结果显示,在不同浓度水氟环境条件下(0、40、80、160 mg·L-1)连续暴露10 d、20 d和30 d时,与对照组相比,中华圆田螺肝胰脏SOD活性在暴露前20 d,中低浓度组活性被诱导升高,高浓度组受抑制降低。暴露30 d时,中低浓度组活性降低,高浓度组逐渐升高。MDA活性在暴露前20 d时,中低浓度组活性整体被诱导升高,高浓度组受抑制降低。暴露30 d时,活性受到显著抑制均低于对照组。GSH活性以诱导为主均高于对照组,POD活性在10 d时均低于对照组,而在20 d时被诱导升高且均高于对照组,30 d时中高浓度以抑制为主。上述研究结果为水质污染控制及生态风险评价提供了基础数据。     

强电磁脉冲环境下计算机设备的防护

探讨了强电磁脉冲对计算机设备的损伤机理和破坏作用,介绍了国内外在强电磁脉冲防护领域的研究发展状况,对计算机脉冲防护技术和措施做了详尽的介绍.结合国内外研究现状和发展趋势,建议加强相关领域的研究,并指出今后的研究方向,以提高强电磁脉冲环境下计算机设备的生存能力.     

Self-reported falls and fall-related injuries among persons aged>or=65 years--United States, 2006

PROBLEM: In 2005, 15,802 persons aged>or=65 years died from fall injuries. How many older adults seek outpatient treatment for minor or moderate fall injuries is unknown. METHOD: To estimate the percentage of older adults who fell during the preceding three months, the Centers for Disease Control and Prevention (CDC) analyzed data from two questions about falls included in the 2006 Behavioral Risk Factor Surveillance System (BRFSS) survey. RESULTS: Approximately 5.8 million (15.9%) persons aged>or=65 years reported falling at least once during the preceding three months, and 1.8 million (31.3%) of those who fell sustained an injury that resulted in a doctor visit or restricted activity for at least one day. DISCUSSION: This report presents the first national estimates of the number and proportion of persons reporting fall-related injuries associated with either doctor visits or restricted activity. SUMMARY: The prevalence of falls reinforces the need for broader use of scientifically proven fall-prevention interventions. IMPACT ON INDUSTRY: Falls and fall-related injuries represent an enormous burden to individuals, society, and to our health care system. Because the U.S. population is aging, this problem will increase unless we take preventive action by broadly implementing evidence-based fall prevention programs. Such programs could appreciably decrease the incidence and health care costs of fall injuries, as well as greatly improve the quality of life for older adults.     

Unintentional strangulation deaths from the "choking game" among youths aged 6-19 years - United States, 1995-2007

The "choking game" is defined as self-strangulation or strangulation by another person with the hands or a noose to achieve a brief euphoric state caused by cerebral hypoxia. Participants in this activity typically are youths (Andrew & Fallon, 2007). Serious neurologic injury or death can result from engaging in this activity. Recent news media reports have described numerous deaths among youths attributed to the choking game. Because no traditional public health dataset collects data on this practice, CDC used news media reports to estimate the incidence of deaths from the choking game. This report describes the results of that analysis, which identified 82 probable choking-game deaths among youths aged 6-19 years during 1995-2007. Seventy-one (86.6%) of the decedents were male, and the mean age was 13.3 years. Parents, educators, and health-care providers should become familiar with warning signs that youths are playing the choking game (Urkin & Merrick, 2006). Impact of industry: By learning about the risk factors for and warning signs of the choking game, parents, educators, and health-care providers may be able to identify youth at risk for playing the game and prevent future deaths.