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1.
The risk of fatal rollover of utility vehicles per 100,000 registered vehicles relative to cars during 1982-87 was strongly correlated to the static stability of the vehicles. Distance between the center of the tires divided by twice the height of center of gravity explained 62 per cent of the variation in fatal rollover rates where rollover was the first harmful event. Statistical controls for 20 major risk factors indicated no correlations that would deflate the correlation between stability and rollover. Low stability utility vehicles roll over more often on the road suggesting that the lateral force of turning is often the tipping force.  相似文献   

2.
Consumers may be unaware of the risk of rollover crashes posed by passenger loads in vehicles with poor roll stability. This analysis demonstrates that certain sports utility vehicles and small pickup trucks have designs that are so unstable that the weight of the passengers in the vehicle affects its propensity to roll over. This effect occurs even though the weight of the loaded vehicle is less than the manufacturer's gross vehicle weight rating. The risk of a fatal, "untripped" rollover crash in vehicles with low roll stability is increased as each passenger is added to the vehicle load.  相似文献   

3.
《Journal of agromedicine》2013,18(3-4):377-379
SUMMARY

Acceleration can decrease the stability of a tractor and result in a tractor rollover on a moderate slope. This report examines an example of an agricultural tractor rollover on a moderate slope and determines a stability index. Based on stability data and the kinematic analysis of a tractor turning on a slop, the paper modifies the index of static stability based on the steady-state operation of a tractor by introducing a dynamic factor.

A tractor rollover was recorded on a video and stability parameters (pitch and roll angles and their rate, as well as yaw rate) were measured by stability sensors. The analysis of the video and stability data in real time showed that the index of tractor stability on a slope is significantly affected by its dynamics (e.g., angle rates and vehicle acceleration). The strong cornering of a tractor wheel and high yaw rate increase the possibility of rollover.  相似文献   

4.
道路伤害的病例对照研究   总被引:7,自引:2,他引:5       下载免费PDF全文
目的:探讨道路伤害危险因素。方法:采用病例对照研究方法,于2001年11月至2002年8月收集沈阳市皇姑区发生机动车交通事故的事故组驾驶员406例,并同期在皇姑区内于随机时间、随机地点调查道路上正常行驶的对照组驾驶员438名。采用统一问卷、面询方法,调查内容包括驾驶员的一般情况,连续驾驶时间,事故/调查前睡眠状况,急、慢性困倦程度(采用Stanford和Epworth困倦量表测量),饮酒,吸烟,驾驶安全态度和行为,车速,车辆状况等。结果:处于慢性困倦状态的驾驶员发生事故的危险性是非困倦状态驾驶员的1.98倍(OR=1.98,95%CI:1.26—3.12),事故组驾驶员的困倦程度高于对照组,但差异无显著性(OR=2.38,95%CI:0.89—6.31)。夜班或倒班发生事故的危险是常白班的2.09倍(OR=2.09,95%CI:1.48—2.94),酒后驾车发生事故的危险性是非酒后驾车的3.59倍(OR=3.59,95%CI:1.13--11.39),无人约束时会违章的驾驶员发生事故的危险性是不违章驾驶员的1.73倍(OR=1.73,95%CI:1.22—2.46)。结论:慢性困倦、夜班或倒班、酒后驾车、违章等是道路伤害的危险因素,急性困倦可能是道路伤害的一个潜在危险因素。  相似文献   

5.
Objective: This study compares the patterns of quad‐related fatal injuries between Australia and New Zealand (NZ). Method: Fatal injuries from July 2007 to June 2012 involving a quad (quad bike or all‐terrain vehicle) were identified from coronial files. Data described the socio‐demographic, injury, vehicle and environment factors associated with incidents. Injury patterns were compared between countries. Results: A total of 101 quad‐related fatalities were identified: 69 in Australia and 32 in NZ (7.3 and 8.0 annual fatalities per 100,000 vehicles). Of these, 95 closed cases were examined in detail and factors in common included fatalities occurring mainly in males, on farms, involving a rollover and resulting in crush injuries to the head and thorax. Helmet use and alcohol/drug involvement were infrequent. Differences were observed with regard to age, season of fatal incident and the presence of a slope. Conclusions: Fatality patterns are broadly similar. The few differences could be attributed to differing agricultural commodity mix, demographics and topography. Implications: This study's findings support harmonised cross‐country injury prevention efforts primarily focused on safe design and engineering principles to reduce this injury burden.  相似文献   

6.
The data presented confirm the advantages of Fe(III)-EDTA as a salt for iron fortification. This iron compound exchanges completely with intrinsic wheat iron in the lumen of the gut. The iron absorption data from this salt tested with six different food vehicles compared with the absorption of ferrous sulfate administered with the same vehicles indicate that while the mean absorption from ferrous sulfate varies from 2 to 30% according to the food vehicle mixed with the salt, the absorption from Fe(III)-EDTA remains practically the same. Apparently, the iron absorption from Fe(III)-EDTA complex is slightly or not affected by the presence of vegetable foods or milk. All these data suggest that only a small amount of iron from this salt, about 10 mg/day, would be necessary to prevent iron deficiency anemia even in those populations relying for their subsistence on vegetable food only.  相似文献   

7.
Objective: There is some evidence to suggest that safety on small-area farms may not be high priority due to economic constraints and lack of knowledge. This has important ramifications for injury and economic burden. The objective of this research was to conduct a pilot study to investigate whether small- to medium-area farms implement fewer safety practices than large-area farms. Methods: Farmers were recruited from farm safety training days, field days, and produce stores in rural New South Wales (NSW), Australia. Small- and medium-area farms less than 500 ha (1235 acres) in size were aggregated for analysis and compared with large-area farms (≥500 ha) for survey items, including safety equipment owned and used, safety practices protecting children, barriers to improving safety, and causes of injury. Results: Overall, small/medium-area farms were found to own less safety equipment and to employ less safety practices than large-area farms. In particular, fewer tractors were fitted with rollover protection structures, there was less signage, less hearing protection, and fewer machinery guides. Injury rates were slightly less for small/medium-area farms, particularly involving vehicles. Small- and medium-area farmers were more likely to report lack of skills as barriers to making safety improvements. Conclusion: This pilot study found some evidence that small/medium-area farms implement fewer safety practices than large-area farms. A larger study is warranted to investigate this further, with particular focus on barriers and ways to overcome them. This could have important ramifications for government policies supporting struggling farmers on small/medium-area farms.  相似文献   

8.
Association of childhood cancer with residential traffic density   总被引:8,自引:0,他引:8  
Data from a recently completed case-referent study of childhood cancer were used to explore a possible role of environmental exposures from traffic exhaust. The street addresses of 328 cancer patients and 262 population-based referents were used to assign traffic density (vehicles per day) as a marker of potential exposure to motor vehicle exhaust. An odds ratio of 1.7 [95% confidence interval (95% CI) 1.0-2.8] was found for the total number of childhood cancers and 2.1 (95% CI 1.1-4.0) for leukemias in a contrast of high and low traffic density addresses (greater than or equal to 500 versus less than 500 vehicles per day). Stronger associations were found with a traffic density cutoff score of greater than or equal to 10,000 vehicles per day, with imprecise odds ratios of 3.1 (95% CI 1.2-8.0) and 4.7 (95% CI 1.6-13.5) for the total number of cancers and leukemias, respectively. Adjustment for suspected risk factors for childhood cancer did not substantially change these results. Though the results are inconclusive, the identified association warrants further evaluation.  相似文献   

9.
Three common sources of environmental exposure to particulate polycyclic aromatic hydrocarbons (PAHs) in Taiwan were chosen for this study. They are smoke of incense burning, exhausts of motor vehicles, and fumes of charcoal burning. The campus environment without any specific PAH sources (nonpoint sources) was chosen as the control. The particulate PAH concentrations in the air samples containing smoke of incense burning were only slightly higher than those in the control. However, the total concentration of particulate PAHs in the air samples with exhausts of motor vehicles and fumes of charcoal burning was about 7.5 times and 22 times higher than those observed in the control, respectively. The mean inhalation amounts of particulate PAHs per unit time are very high both in samples with exhausts of motor vehicles (13.9 ng/min) and fumes of charcoal burning (38.1 ng/min). The exposure dose of 22 PAHs per day ranged from 3.18 to 18.0 μg/day under four exposure conditions. Moreover, the personal inhalation BaPeq levels are in the range of 0.4 to 1.55 μg/day. Received: 29 August 2001/Accepted: 7 November 2002  相似文献   

10.
ABSTRACT: BACKGROUND: This study investigated the number of pedometer assessment occasions required to establish habitual physical activity in African American adults. METHODS: African American adults (mean age 59.9 +/- 0.60 years; 59 % female) enrolled in the Diet and Physical Activity Substudy of the Jackson Heart Study wore Yamax pedometers during 3-day monitoring periods, assessed on two to three distinct occasions, each separated by approximately one month. The stability of pedometer measured PA was described as differences in mean steps/day across time, as intraclass correlation coefficients (ICC) by sex, age, and body mass index (BMI) category, and as percent of participants changing steps/day quartiles across time. RESULTS: Valid data were obtained for 270 participants on either two or three different assessment occasions. Mean steps/day were not significantly different across assessment occasions (p values > 0.456). The overall ICCs for steps/day assessed on either two or three occasions were 0.57 and 0.76, respectively. In addition, 85 % (two assessment occasions) and 76 % (three assessment occasions) of all participants remained in the same steps/day quartile or changed one quartile over time. CONCLUSION: The current study shows that an overall mean steps/day estimate based on a 3-day monitoring period did not differ significantly over 4 - 6 months. The findings were robust to differences in sex, age, and BMI categories. A single 3-day monitoring period is sufficient to capture habitual physical activity in African American adults.  相似文献   

11.
汽车驾驶员的高血压危险因素分析   总被引:4,自引:0,他引:4  
目的了解汽车驾驶员的原发性高血压患病情况及主要危险因素,为该人群制定适宜的防治措施。方法采用现况调查的方法,对重庆市746名20~60岁的男性驾驶员行问卷调查、体格检查和血压测量等。同期检测了884名男性非驾驶员人员的血压值。结果男性驾驶员的高血压标化患病率为28.3%,高于非驾驶员18.26%。驾龄、平均每天开车时间、驾驶车型、工作责任和工作紧张感等职业因素与驾驶员高血压有关。多因素Logistic分析显示驾龄、工作责任和工作紧张感、父母患高血压及体重指数(BMI)>25是驾驶员高血压的主要危险因素。结论职业紧张等因素与驾驶员高血压患病有关,需采取相应的综合防治措施。  相似文献   

12.
To assess the efficacy of occupant protection systems, the authors measured the mortality reduction associated with air bag deployment and seat belt use for drivers involved in head-on passenger car collisions in the United States. They used a matched case-control design of all head-on collisions involving two passenger cars reported to the Fatality Analysis Reporting System in 1992-1997, and driver mortality differences between the paired crash vehicles for air bag deployment and seat belt use were measured with matched-pair odds ratios. Conditional logistic regression was used to adjust for multiple effects. There were 9,859 head-on collisions involving 19,718 passenger cars and drivers. Air bag deployment reduced mortality 63% (crude odds ratio (OR) = 0.37, 95% confidence interval (CI): 0.32, 0.42), while lap-shoulder belt use reduced mortality 72% (OR = 0.28, 95% CI: 0.25, 0.31). In a conditional logistic model that adjusted for vehicle (rollover, weight, age) and driver (age, sex) factors, air bags (OR = 0.71, 95% CI: 0.58, 0.87) and any combination of seat belts (OR = 0.25, 95% CI: 0.22, 0.29) were both associated with reduced mortality. Combined air bag and seat belt use reduced mortality by more than 80% (OR = 0.18, 95% CI: 0.13, 0.25). Thus, this study confirms the independent effect of air bags and seat belts in reducing mortality.  相似文献   

13.
ObjectiveTo quantify the magnitude of the association between the type of vehicle and the probability of being responsible for a collision between two or more vehicles.MethodFrom the registry of road crashes with victims maintained by the Spanish Traffic General Directorate (2014 and 2015), a matched case-control study was designed. Cases were offending drivers involved in the 27,630 collisions between two or more vehicles in which only one of the drivers had committed a driving mistake or offence. Each case was matched with the non-offending drivers of the vehicles involved in the same crash: in all, 31,219 controls were included. Apart from the commission of offences and the type of vehicle involved, we got information about other characteristics of the driver (age, sex, etc.) and about the vehicle (age). Odds ratios (OR) were calculated in order to quantify the association between each type of vehicle and the odds of being responsible for the collision, crude and adjusted (by conditioned logistic regression) by the rest of collected variables.ResultsIn comparison with private cars, bicycles had a lower risk of causing a collision (adjusted OR: .30), and also mopeds (aOR: .52) and buses (aOR: .63). Vans (aOR: 1.19) and four-wheel vehicles (aOR: 1.33) increased the risk.ConclusionTwo-wheeled vehicles and buses had a lower risk of causing collisions than private cars. This association is independent of some of the characteristics of the driver, as well as the age of the vehicle.  相似文献   

14.
目的:探索IS09001:2000质量管理体系的管理方法在流动手术车规模化手术管理中的有效性和可行性。方法:引进IS09001:2000质量管理体系,编写和建立质量管理体系的文件,组织实施并有效运行;对2802例白内障规模化手术进行回顾性总结。结果:2年来,利用手术车为2802名患者施行复明手术,平均26.4台/天。术后第一天裸眼视力≥0.05者2635眼(94.04%),I〉0.3者1533眼(54.71%)。结论:流动手术车是一个高风险医疗项目,施行IS09001标准可进一步提高医疗安全性,基本实现全程、全面、适时和事前控制,无一例发生感染及严重并发症、医疗差错及医疗投诉,终末质量得到提升。  相似文献   

15.
The potential role of NaFeEDTA as an iron fortificant   总被引:1,自引:0,他引:1  
Ethylene diamine tetraacetic acid (EDTA) is a hexadentate chelator, which can combine with virtually every metal in the periodic table. CaNa2EDTA and Na2EDTA (ADI 2.5 mg EDTA/kg body weight/day) are widely used as sequestering agents in canned products, while NaFeEDTA is a promising iron fortificant. Binding of EDTA with iron is favored in the acid milieu of the stomach, irrespective of whether the EDTA is administered as CaNa2EDTA, Na2EDTA, or NaFeEDTA, but in the more alkaline medium of the duodenum the iron is exchanged, in part, with other metals. The iron released from EDTA is absorbed by the normal physiological mechanisms. When NaFeEDTA is present in a meal, the iron moiety exchanges with the intrinsic food iron and the EDTA partially protects the iron in this common non-heme iron pool from the effects of inhibitors of iron absorption, such as phytates and polyphenols. When iron is added as NaFeEDTA to an inhibitory meal, it is two to three times better absorbed than is iron added as ferrous sulfate. It also has a similar effect on the intrinsic food iron in the meal. Fortification with NaFeEDTA is most efficacious when administered with cereal- and legume-based diets but offers no advantages over other fortificants when added to meals of high bioavailability. Its potential as a fortificant has been confirmed in five extended fortification trials carried out in developing countries. There is no evidence that NaFeEDTA in the dose range proposed for food fortificants (5 to 10 mg iron daily) will have any direct toxic effects. Na2EDTA and CaNa2EDTA have proved safe over a number of years, while the Joint FAO/WHO Expert Committee on Food Additives concluded in 1999 that NaFeEDTA "could be considered safe when used in supervised fortification programs". Animal and human studies, including the results of two fortification trials, suggest that NaFeEDTA has little or no effect on overall zinc metabolism. Indeed, if anything, it increases zinc and possibly copper absorption. Data on potentially toxic metals, such as lead mercury, aluminum, and manganese, are limited but the evidence that is available is uniformly negative thus far. Further studies in this field are desirable. The long-term potential of NaFeEDTA fortification to cause iron overload is conjectural but the available evidence suggests that homeostatic controls would prevent excess iron accumulation in the normal population. NaFeEDTA, which is pale yellow in color, causes fewer organoleptic changes in a number of stored vehicles, including cereals, than do other soluble iron salts. Other potential vehicles include condiments, several of which have been successfully used in fortification trials. What is currently lacking is a consolidated body of published evidence on the stability of NaFeEDTA during processing, storage, and household cooking in widely consumed food vehicles, coupled with standardized testing of consumer acceptance of each fortified vehicle. While NaFeEDTA seems to be an appropriate fortificant for developing countries, its cost is about six to eight times that of ferrous sulfate in terms of equivalent amounts of iron. Its better absorption (a factor of 2-3) might make it possible to halve the daily fortification level but, it still remains expensive and there is a pressing need for food grade NaFeEDTA at more affordable prices. Another possible option is the use of other salts of EDTA (Na2EDTA or Ca Na2EDTA) together with a soluble source of iron, such as ferrous sulfate. The combination has been shown to be as effective as NaFeEDTA when the EDTA:Fe molar ratio is between 1:2 and 1:1. This approach is, however, only feasible with vehicles that are stored for short periods because of ferrous sulfate's propensity to cause organoleptic changes. The search for an iron source that is more stable but at the same time available to combine with EDTA has been unsuccessful thus far. Target populations for fortification with NaFeEDTA include all those that subsist on cereal- and legume-based diets, with the most appropriate vehicles being cereal products and condiments. The fortification of infant milk and cereal formulas with NaFeEDTA does not seem appropriate, since the amounts of NaFeEDTA required for effective fortification would be close to the acceptable daily intake (ADI) of 2.5 mg EDTA/kg body weight/day.  相似文献   

16.
I examined the potential for a lower risk of death compatible with increased fuel economy among 67 models of 1999-2002 model year cars, vans, and sport-utility vehicles (SUVs) during the calendar years 2000 to 2004. The odds of death for drivers and all persons killed in vehicle collisions were related to vehicle weight, size, stability, and crashworthiness. I calculated that fatality rates would have been 28% lower and fuel use would have been reduced by 16% if vehicle weights had been reduced to the weight of vehicles with the lowest weight per size, where size is measured by the lateral distance needed to perform a 180-degree turn. If, in addition, all vehicles had crashworthiness and stability equal to those of the top-rated vehicles, more than half the deaths involving passenger cars, vans, and SUVs could have been prevented by vehicle modifications.  相似文献   

17.
OBJECTIVES: This study reviewed the effectiveness of interventions in preventing occupational injuries among workers in agriculture. METHODS: Randomized controlled trials, controlled before-after studies, and interrupted time-series studies assessing interventions aimed at preventing injuries among workers in agriculture were considered. MEDLINE and five other databases were searched up to June 2006. Two authors independently assessed the eligibility of studies and the methodological quality of the ones included. Randomized controlled trials were combined in a meta-analysis. Interrupted time-series studies were reanalyzed to assess the immediate and progressive effect on injuries. RESULTS: Five randomized controlled trials and three interrupted time-series studies met the inclusion criteria. Six studies evaluated educational interventions and financial incentives, and two studies evaluated the effect of legislation. Three randomized controlled trials on educational interventions with 4670 adult participants did not indicate any injury-reducing effect, with a rate ratio of 1.02 (95% confidence interval 0.87-1.20), nor did two randomized controlled trials among children (6895 participants). Financial incentives decreased the injury level immediately after the intervention in one interrupted time-series study. Banning endosulfan pesticide in Sri Lanka led to a significant decrease in the trend of poisonings over time. Legislation requiring rollover protective structures on all tractors in Sweden did not produce a reduction in injuries, but the same requirement for new tractors was associated with a decrease in fatal injuries. CONCLUSIONS: The reviewed studies provided no evidence that educational interventions are effective in decreasing injury rates among agricultural workers. Financial incentives may be a better means of reducing injury rates. Banning highly toxic pesticides may be effective. Legislation on safety devices on tractors yielded contradictory results.  相似文献   

18.
19.
L F Woodard  R L Jasman 《Vaccine》1985,3(2):137-144
Many of the most potent immunoadjuvants for inclusion in vaccines are extremely hydrophobic surfactants. Lipophilic vehicles are needed as carriers for these water-insoluble adjuvants and to provide the hydrophilic-hydrophobic interfacial surface at which they act. We used emulsifiers comprised of fatty acid esters of polyoxyethylene sorbitan (Tweens) or sorbitan (Spans) to prepare oil-in-water (O/W) emulsions of hexadecane. Emulsion stability could be predicted from a ratio of spectrophotometric absorbance readings at 800 and 400 nm but not from published hydrophilelipophile balance (HLB) values. Emulsions that were stable even after heating or freezing resulted when equal volumes of hexadecane and a 70:30 blend of Tween 80/Span 80(T80/S80) were mixed and then diluted with normal saline solution to the desired hexadecane concentration. This blend of monooleate esters has an HLB value of 11.8. Other Tween-Span formulations were mixed to yield emulsifiers with the same HLB value, but only those that contained either T80 or S80 were effective stabilizers. Instability resulted when both esters were derived from saturated fatty acids. Addition of bovine serum albumin (BSA) antigen to the oil phase of 5% hexadecane emulsions tended to destabilize the emulsions, especially at higher protein concentrations. The surface active adjuvant, hexadecylamine, increased emulsion stability. Highest antibody responses in mice were seen when BSA was added to the internal phase of emulsions, i.e., the oil phase of O/W emulsions and the aqueous phase of W/O (Freund's) emulsions. Addition of the hydrophilic T80 to the aqueous phase of O/W emulsions was detrimental to antibody production. In general, stability, oil concentration, and T80/S80 concentration of emulsions had little effect on IgG levels.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

20.
The investigation of potential adverse health effects of urban traffic-related air pollution is hampered by difficulties encountered with exposure assessment. Usually public measuring sites are few and thereby do not adequately describe spatial variation of pollutant levels over an urban area. In turn, individual monitoring of pollution exposure among study subjects is laborious and expensive. We therefore investigated whether traffic characteristics can be used to adequately predict benzene, NO2, and soot concentrations at individual addresses of study subjects in the city area of Munich, Germany. For all road segments with expected traffic volumes of at least 4000 vehicles a day (n = 1840), all vehicles were counted manually for a single weekday in 1995. The proportion of vehicles in "stop-go" mode, an estimate of traffic jam, was determined. Furthermore, annual concentrations of benzene, NO2, and soot from 18 high-concentration sites (means: 8.7, 65.8, and 12.9 micrograms/m3, respectively) and from 16 school sites with moderate concentrations (means: 2.6, 32.2, and 5.7 micrograms/m3, respectively) were measured from 1996 to 1998. Statistical analysis of the data was performed using components of two different statistical models recently used to predict air pollution levels in comparable settings. Two traffic characteristics, traffic volume and traffic jam percentage, adequately described air pollutant concentrations (R2: 0.76-0.80, P < 0.0001). This study shows that air pollutant concentrations can be accurately predicted by two traffic characteristics and that these models compare favorably with other more complex models in the literature.  相似文献   

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