Active transportation to school: trends among U.S. schoolchildren, 1969-2001

BACKGROUND: Rising rates of overweight children have focused attention on walking and biking to school as a means to increase children's physical activity levels. Despite this attention, there has been little documentation of trends in school travel over the past 30 years or analysis of what has caused the changes in mode choice for school trips. METHODS: This article analyzes data from the 1969, 1977, 1983, 1990, 1995, and 2001 National Personal Transportation Survey conducted by the U.S. Department of Transportation to document the proportion of students actively commuting to school in aggregate and by subgroups and analyze the relative influence of trip, child, and household characteristics across survey years. All analyses were done in 2006. RESULTS: The National Personal Transportation Survey data show that in 1969, 40.7% (95% confidence interval [CI]=37.9-43.5) of students walked or biked to school; by 2001, the proportion was 12.9% (95% CI=11.8-13.9). Distance to school has increased over time and may account for half of the decline in active transportation to school. It also has the strongest influence on the decision to walk or bike across survey years. CONCLUSIONS: Declining rates of active transportation among school travelers represents a worrisome loss of physical activity. Policymakers should continue to support programs designed to encourage children to walk to school such as Safe Routes to School and the Centers for Disease Control and Prevention's KidsWalk. In addition, officials need to design policies that encourage schools to be placed within neighborhoods to ensure that the distance to school is not beyond an acceptable walking distance.     

Synthesis,characterization, and monoamine transporter activity of the new psychoactive substance 3′,4′‐methylenedioxy‐4‐methylaminorex (MDMAR)

The recent occurrence of deaths associated with the psychostimulant cis‐4,4′‐dimethylaminorex (4,4′‐DMAR) in Europe indicated the presence of a newly emerged psychoactive substance on the market. Subsequently, the existence of 3,4‐methylenedioxy‐4‐methylaminorex (MDMAR) has come to the authors' attention and this study describes the synthesis of cis‐ and trans‐MDMAR followed by extensive characterization by chromatographic, spectroscopic, mass spectrometric platforms and crystal structure analysis. MDMAR obtained from an online vendor was subsequently identified as predominantly the cis‐isomer (90%). Exposure of the cis‐isomer to the mobile phase conditions (acetonitrile/water 1:1 with 0.1% formic acid) employed for high performance liquid chromatography analysis showed an artificially induced conversion to the trans‐isomer, which was not observed when characterized by gas chromatography. Monoamine release activities of both MDMAR isomers were compared with the non‐selective monoamine releasing agent (+)‐3,4‐methylenedioxymethamphetamine (MDMA) as a standard reference compound. For additional comparison, both cis‐ and trans‐4,4′‐DMAR, were assessed under identical conditions. cis‐MDMAR, trans‐MDMAR, cis‐4,4′‐DMAR and trans‐4,4′‐DMAR were more potent than MDMA in their ability to function as efficacious substrate‐type releasers at the dopamine (DAT) and norepinephrine (NET) transporters in rat brain tissue. While cis‐4,4′‐DMAR, cis‐MDMAR and trans‐MDMAR were fully efficacious releasing agents at the serotonin transporter (SERT), trans‐4,4′‐DMAR acted as a fully efficacious uptake blocker. Currently, little information is available about the presence of MDMAR on the market but the high potency of ring‐substituted methylaminorex analogues at all three monoamine transporters investigated here might be relevant when assessing the potential for serious side‐effects after high dose exposure. Copyright © 2014 John Wiley & Sons, Ltd.     

The HLA dictionary 1999: a summary of HLA-A, -B, -C, -DRB1/3/4/5, -DQB1 alleles and their association with serologically defined HLA-A, -B, -C, -DR and -DQ antigens

This report presents serologic equivalents of 90 HLA-A, 190 HLA-B and 145 HLA-DRB1 alleles. The equivalents cover over 70% of the presently identified HLA-A, -B and -DRB1 alleles. The dictionary is an update of the one published in 1997 and now also includes equivalents for HLA-C, DRB3, DRB4, DRB5 and DQB1 alleles. The data summarize information obtained by the WHO HLA Nomenclature Committee, the International Cell Exchange (UCLA), the National Marrow Donor Program (NMDP) and by individual laboratories. In addition, a listing is provided of alleles which are expressed as antigens with serologic reaction patterns that differ from the well-established HLA specificities and that often lack official WHO nomenclature. The provided equivalents will be useful in guiding searches for unrelated donors in which patients and/or potential donors are typed by either serology or DNA-based methods. These equivalents will also serve typing and matching procedures for organ transplant programs where HLA typings from donors and from recipients on waiting lists represent mixtures of serologic and molecular typings. Some guidelines are provided for the use of appropriate WHO HLA nomenclature for serological typings and for generic and allele specific typings obtained with molecular methods. The tables with HLA equivalents and the questionnaire for submission of serology on poorly identified alleles will also be available at the WMDA web page: www:bmdw.org/wmda.     

Low back pain in pilots

A questionnaire on low back pain (LBP) was administered to 373 fighter pilots, 165 transport pilots, and 264 helicopter pilots. Helicopter pilots had more pain during flight than did fighter or transport pilots (34.5%, 12.9%, and 5.1%, respectively). A history of LBP temporally unassociated with flight was found in 26.5% of helicopter pilots, 31.5% of transport pilots and 25.2% of fighter pilots. We conclude that, despite the pain experienced by helicopter pilots in flight, they are not at increased risk for LBP unassociated with flight.     

The failure analysis of composite material flight helmets as an aid in aircraft accident investigation.

Understanding why a flying helmet fails to maintain its integrity during an accident can contribute to an understanding of the mechanism of injury and even of the accident itself. We performed a post-accident evaluation of failure modes in glass and aramid fibre-reinforced composite helmets. Optical and microscopic (SEM) techniques were employed to identify specific fracture mechanisms. They were correlated with the failure mode. Stress and energy levels were estimated from the damage extent. Damage could be resolved into distinct impact, flexure and compression components. Delamination was identified as a specific mode, dependent upon the matrix material and bonding between the layers. From the energy dissipated in specific fracture mechanisms we calculated the minimum total energy imparted to the helmet-head combination and the major injury vector (MIV) direction and magnitude. The level of protection provided by the helmet can also be estimated.     

Manic syndrome in AIDS.

A manic syndrome in eight patients with AIDS is described. On the basis of clinical, neuropsychological, laboratory, magnetic resonance imaging, and epidemiological evidence, the authors suggest that the manic syndrome was secondary to HIV infection. The patients also developed concomitant cognitive impairment.