Self-excited triggered vacuum gap

The self-triggering action of the TVG under DC conditions using the same power source as the main circuit is described. Because of the low impedance of the power source compared with the thyratron pulse generator, the TVG can be triggered with voltages as low as 85 V. It is found that circuit conditions influence the minimum stable arc currents that can be sustained.

Mediation of improvements in sun protective and skin self-examination behaviours: Results from the healthy text study

Objective Melanoma is on the rise, especially in Caucasian populations exposed to high ultraviolet radiation such as in Australia. This paper examined the psychological components facilitating change in skin cancer prevention or early detection behaviours following a text message intervention. Methods The Queensland-based participants were 18 to 42 years old, from the Healthy Text study (N = 546). Overall, 512 (94%) participants completed the 12-month follow-up questionnaires. Following the social cognitive model, potential mediators of skin self-examination (SSE) and sun protection behaviour change were examined using stepwise logistic regression models. Results At 12-month follow-up, odds of performing an SSE in the past 12 months were mediated by baseline confidence in finding time to check skin (an outcome expectation), with a change in odds ratio of 11.9% in the SSE group versus the control group when including the mediator. Odds of greater than average sun protective habits index at 12-month follow-up were mediated by (a) an attempt to get a suntan at baseline (an outcome expectation) and (b) baseline sun protective habits index, with a change in odds ratio of 10.0% and 11.8%, respectively in the SSE group versus the control group. Conclusions Few of the suspected mediation pathways were confirmed with the exception of outcome expectations and past behaviours. Future intervention programmes could use alternative theoretical models to elucidate how improvements in health behaviours can optimally be facilitated.

Magnetic Field Due to the Self-Gravity-Induced Electric Polarization of a Rotating Massive Body

he notion of the gravity-induced electric field has been applied to an entire self-gravitating massive body. The resulting electric polarization of the otherwise neutral body, when taken in conjunction with the latter's rotation, is shown to generate an axial-magnetic field of the right type and order of magnitude for certain astrophysical objects. In the present treatment the electric polarization is calculated in the ion-continuum Thomas-Fermi approximation while the electrodynamics of the continuous medium is treated in the nonrelativistic approximation.

Reactions to changes in work control: Implications for self-determined and non-self-determined individuals

We investigate the extent to which individuals’ global motivation (self-determined and non-self-determined types) influences adjustment (anxiety, positive reappraisal) and engagement (intrinsic motivation, task performance) in reaction to changes to the level of work control available during a work simulation. Participants (N = 156) completed 2 trials of an inbox activity under conditions of low or high work control—with the ordering of these levels varied to create an increase, decrease, or no change in work control. In support of the hypotheses, results revealed that for more self-determined individuals, high work control led to the increased use of positive reappraisal. Follow-up moderated mediation analyses revealed that the increases in positive reappraisal observed for self-determined individuals in the conditions in which work control was high by Trial 2 consequently increased their intrinsic motivation toward the task. For more non-self-determined individuals, high work control (as well as changes in work control) led to elevated anxiety. Follow-up moderated mediation analyses revealed that the increases in anxiety observed for non-self-determined individuals in the high-to-high work control condition consequently reduced their task performance. It is concluded that adjustment to a demanding work task depends on a fit between individuals’ global motivation and the work control available, which has consequences for engagement with demanding work.