Injury and frequency of use of playground equipment in public schools and parks in Brisbane, Australia

Objective: The purpose of this study was to determine the frequency of use of play equipment in public schools and parks in Brisbane, Australia, and to estimate an annual rate of injury per use of equipment, overall and for particular types of equipment. Methods: Injury data on all children injured from playground equipment and seeking medical attention at the emergency department of either of the two children's hospitals in the City of Brisbane were obtained for the years 1996 and 1997. Children were observed at play on five different pieces of play equipment in a random sample of 16 parks and 16 schools in the City of Brisbane. Children injured in the 16 parks and schools were counted, and rates of injury and use were calculated. Results: The ranked order for equipment use in the 16 schools was climbing equipment (3762 uses), horizontal ladders (2309 uses), and slides (856 uses). Each horizontal ladder was used 2.6 times more often than each piece of climbing equipment. Each horizontal ladder was used 7.8 times more than each piece of climbing equipment in the sample of public parks. Slides were used 4.6 times more than climbing equipment in parks and 1.2 times more in public schools. The annual injury rate for the 16 schools and 16 parks under observation was 0.59/100000 and 0.26/100000 uses of equipment, respectively. Conclusions: This study shows that annual number of injuries per standardized number of uses could be used to determine the relative risk of particular pieces of playground equipment. The low overall rate of injuries/100000 uses of equipment in this study suggests that the benefit of further reduction of injury in this community may be marginal and outweigh the economic costs in addition to reducing challenging play opportunities.

Properties of the stochastic Gross-Pitaevskii equation: finite temperature Ehrenfest relations and the optimal plane wave representation

We present Ehrenfest relations for the high temperature stochastic Gross-Pitaevskii equation description of a trapped Bose gas, including the effect of growth noise and the energy cutoff. A condition for neglecting the cutoff terms in the Ehrenfest relations is found which is more stringent than the usual validity condition of the truncated Wigner or classical field method-that all modes are highly occupied. The condition requires a small overlap of the nonlinear interaction term with the lowest energy single particle state of the noncondensate band, and gives a means to constrain dynamical artefacts arising from the energy cutoff in numerical simulations. We apply the formalism to two simple test problems: (i) simulation of the Kohn mode oscillation for a trapped Bose gas at zero temperature, and (ii) computing the equilibrium properties of a finite temperature Bose gas within the classical field method. The examples indicate ways to control the effects of the cutoff, and that there is an optimal choice of plane wave basis for a given cutoff energy. This basis gives the best reproduction of the single particle spectrum, the condensate fraction and the position and momentum densities.

Predictors of cultural adjustment: Intergroup status relations and boundary permeability

We examined intergroup predictors of cultural adjustment among Asian international students in Australia. Sociostructural beliefs (status, legitimacy, and permeability) and initial adjustment were assessed (N = 113) at Time 1, and measures of adjustment were obtained (N = 80) at Time 2 eight weeks later. International students who perceived their cultural group to be relatively low in status experienced lower levels of psychological adjustment. Also, as expected, the effects of status were moderated by perceptions of both the permeability of intergroup boundaries and the legitimacy of the status differential. At high levels of legitimacy, perceptions of permeable group boundaries were associated with better psychological, sociocultural, and academic adjustment among international students perceiving their group to be low in status, but lower levels of adjustment among students who perceived their group to be high in status. At low levels of legitimacy, irrespective of group status position, perceived permeability was not related to adjustment.

Migration and transfer from Germany to Britain, 1660 to 1914:historical relations and comparisons

From the seventeenth until the twentieth century, Germans formed a prominent immigrant group in Great Britain. Their number included many occupations, and many occupied positions of significance. This volume brings together the most recent research on the subject, and places it firmly in the context of migration and transnational studies. It focuses on the significance of migration to cultural transfer, and highlights the contribution of Germans to the course of British history.