Qualitative analysis of a pendulum with a periodically varying length is conducted. It is proved that there are two periodic solutions having a prescribed amplitude A(n and a period 1 which is an even multiple k of the excitation period. Stability analysis is carried out for the principal parametric oscillations (k"2). In this connection it is shown that such a pendulum cannot serve as a mathem...

Background Connective tissue graft (CTG) is considered as the gold standard for the treatment of gingival recessions (GR). There are few studies assessing the complications that can arise in the donor site when harvesting a connective tissue graft (CTG) and how the harvesting technique can influence those complications. Material and Methods A retrospective clinical study was carried out in or...

Across six field and lab experiments, we found that impaired self-control fosters compliance with charitable requests. Experiments 1 and 2 showed that self-regulatory resource depletion was induced when participants yielded to the initial requests of a foot-in-the-door script aimed at procuring volunteer behavior. Experiment 3 demonstrated that self-regulatory resource depletion mediated the ef...

Gender and Work Hours Transitions in Australia: Drop Ceilings and Trap-Door Floors We introduce the ideas of “drop ceilings”, that full-time employees who switch to reduced hours thereafter face an hours ceiling such that a return to full-time employment is difficult, and of “trap-door floors”, that full-time employees may be denied the opportunity to reduce their hours and instead face a choic...

The present study investigates the effects of different types of concurrent feedback on the acquisition of perceptual-motor skills. Twenty participants walked through virtual corridors in which rhythmically opening and closing sliding doors were placed. The participants aimed to adjust their walking speed so as to cross the doors when the doors were close to their maximal aperture width. The hi...

Stalking is a dangerous and devastating crime that irrevocably changes the lives of victims but is frequently misunderstood and minimized. Victims report that their lives are never the same after they have been stalked. Stalking is prevalent and gender-neutral and occurs across all socioeconomic lines and in all clinical settings. The prevalence of stalking provides many opportunities for socia...

The disadvantages caused by the swing of a fish body were analyzed. The coordinate system of a two-joint robot fish was built. The hydrodynamic analysis of robot fish was developed. The dynamic simulation of a two-joint robot fish was carried out with the ADAMS software. The relationship between the swing of fish body and the mass distribution of robot fish, the relationship between the swing o...

Swing-leg retraction, the backward rotation of the swing leg just prior to ground contact, is observed in human locomotion. While several advantages of swingleg retraction, like gait stability and perturbation rejection, are shown by conceptual models, there is currently very little experimental data on swing-leg retraction in human motion. In this paper, kinematic data for twenty-eight subject...