Rolling moments in a trailing vortex flow field

Pressure distributions are presented which were measured on a wing in close proximity to a tip vortex of known structure generated by a larger, upstream semispan wing. Overall loads calculated by integration of these pressures are checked by independent measurements made with an identical model mounted on a force balance. Several conventional methods of wing analysis are used to predict the loads on the following wing. Strip theory is shown to give uniformly poor results for loading distribution, although predictions of overall lift and rolling moment are sometimes acceptable. Good results are obtained for overall coefficients and loading distribution by using linearized pressures in vortex-lattice theory in conjunction with a rectilinear vortex. The equivalent relation from reverse-flow theory that can be used to give economic predictions for overall loads is presented

Optical monitoring of gamma-ray source fields

The three gamma-ray burst source fields GBS1028+46, GBS1205+24, and GBS2252-03 have been monitored for transient optical emission for a combined total of 52 hours. No optical events were seen. The limiting magnitude for the search was M sub V = 15.8 longer and M sub V = 17.0 for 6.0 s or longer

Mortality from head injury over four decades in Scotland

Although the causes of head injury, the population at risk and approaches to prevention and treatment are continually evolving, there is little information about how these are reflected in patterns of mortality over time. We used population based comprehensive data uniquely available in Scotland to investigate changes in the total numbers of deaths from 1974 to 2012, as well as the rates of head injury death, from different causes, overall and in relation to age and gender. Total mortality fell from an annual average of 503 to 339 with a corresponding annual decrease in rate from 9.6 to 6.4 per 100,000 population, the decline substantially occurring between 1974 and 1990. Deaths in children fell strikingly but rose in older people. Deaths in males fell to a greater extent than females but remained at a higher rate overall. Initially, a transport accident accounted for most deaths but these fell by 80%, from 325 per year to 65 per year over the 39 year period. Deaths from falling and all other causes did not decline, coming to outnumber transport accident deaths by 1998, which accounts for the overall absence of change in total mortality in recent years. In order to reduce mortality in the future, more effective measures to prevent falls are needed and these strategies will vary in younger adults (where alcohol is often a factor), and in older adults where infirmity can be a cause. In addition, measures to sustain reductions in transport accidents need to be maintained and further developed