Pedestrian fatalities, Atlanta Metropolitan Statistical Area and United States, 2000-2004

Motor vehicle crashes killed almost 5,000 pedestrians in 2005 in the United States. Pedestrian risk may be higher in areas characterized by urban sprawl. From 2000 to 2004, pedestrian fatality rates declined in the United States, but the Atlanta metropolitan statistical area did not experience the same decline. Pedestrian fatality rates for males, Hispanics, and the 15–34 and 35–54 year age groups were higher in Atlanta than in the United States overall. Pedestrian safety interventions should be targeted to high-risk populations and localized pedestrian settings.     

Impact of the toxicity of Cylindrospermopsis raciborskii (Woloszynska) Seenayya & Subba Raju on laboratory rats in vivo

In vivo laboratory studies of toxicity were performed on Wistar rats using a methanol extract produced by the natural population of Cylindrospermopsis raciborskii (abundance of 2.13 × 10⁵ trichomes mL⁻¹) collected at Aleksandrovac Lake (Serbia). HPLC analysis showed that the extract contains 6.65 μg cylindrospermopsin (CYN) mg⁻¹. The rats were killed 24 or 72 h after a single intraperitoneal injection of C. raciborskii extract in concentrations of 1500, 3000, 6000 and 12,000 μg kg⁻¹ body weight (bw) and an equivalent amount of CYN as present in the highest dose of the extract (79.80 μg CYN kg⁻¹ bw). The genotoxic effect on the livers treated with C. raciborskii was evaluated using comet assay and potential induction of oxidative stress as the toxicity mechanism associated with the presence of CYN in extract. The results from the analyses of DNA damage in the comet tail length, tail moment and percentage of DNA in the tail in the liver indicated that administration of extract and CYN present statistically significant difference when compared with the negative control group. Although an increase in the frequency of selected parameters induced by the CYN was observed in the liver, this damage was less than the damage resulting from the administration of the highest dose of extract. The changes in the biochemical parameters of the hepatic damage showed that the application of single doses of the extract and CYN did not cause serious liver damage in rats. The extract and CYN significantly increased oxidative stress in rats’ liver after a single exposure.

     

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.     

An investigation of aqueous activity coefficients at low concentrations

The activity of a chemical in solution determines its tendency to move into other media. At low concentrations (<0.01M) it is generally considered to be linearly related to concentration. A hypothetical model based on the structure of liquid water is discussed which could cause deviations from this linearity in the ppb region, a concentration much lower than that normally investigated thermodynamically, but one of great importance environmentally. Headspace experiments are reported with carbon tetrachloride and chloroform in water at concentrations down to ～10^?3 ppb but no such deviations were discerned.     

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.     

油浸变压器排油注氮装置在500kV变电站的设计与应用

在分析500kV变电站主变压器消防系统的现状,比较3类消防系统优缺点的基础上,详细论述了主变排油注氮装置的结构组成、工作原理、参数计算、控制系统设计以及需要注意的事项等,为下一步排油注氮装置的推广应用打下基础.     

The role of sales of new motorcycles in a recent increase in motorcycle mortality rates

INTRODUCTION: The National Highway Traffic Safety Administration (NHTSA) has reported that mortality rates from crashes among motorcycle riders in the United States increased from 21.0 per 100 million motorcycle miles traveled in 1997 to 38.4 per 100 million motorcycle miles traveled in 2003. At the same time, annual domestic sales of new, on-road motorcycles increased from 247,000 in 1997 to 648,000 in 2003. METHOD: This study used data from the NHTSA Fatality Analysis Reporting System and annual sales figures for on-road motorcycles to determine if newer motorcycles were more likely to be involved in fatal crashes and if fatal crashes involving newer motorcycles could account for the mortality increase after 1997. RESULTS: Mortality rates were 7.9, 8.1, 5.4, and 2.9 per 10,000 motorcycles sold for motorcycles <1, 1-3, 4-6, and 7-11 years old, respectively, from 1994 to 2003. Assuming complete registration, the number of motorcycles sold during the 2000-2003 time period accounted for 42.4% of the total number of motorcycles registered in 2003. Motorcycles sold during 2000-2003 were associated with 52.5% of all motorcycle deaths in 2003. The increase in the number of deaths associated with motorcycles less than four years old between 1997 and 2003 accounted for 78.1% of the total increase in motorcyclist deaths over this time period. CONCLUSIONS: Two possible explanations for the association between high sales volumes and mortality rates are: (a) increased exposure from more extensive use of motorcycles when they are new; and (b) inexperience with motorcycle riding or with specific motorcycles. IMPACT ON INDUSTRY: This study suggests that the deaths of growing numbers of motorcyclists are a consequence of the financial success of the motorcycle industry.