sam andrews

Abstract A Prosthetic Foot Loading Apparatus (PFLA) was modified and improved to measure the mechanical properties of different prosthetic feet. In this paper the properties of a SACH foot and a Flexwalk foot are examined to demonstrate application of the device. ...

This paper introduces a passive piezoelectric shunt controller, for damping multiple modes of a flexible structure using one piezoelectric transducer. The series-parallel impedance structure has a number of advantages over to previous techniques; it is simpler to implement, requires less passive elements and contains smaller inductors values. The vibration control strategy is validated through experimental work on a piezoelectric laminated cantilever structure.

This article focuses on bullying among students and explores the ways it affects the attendance of senior high school students in Ghana. It explores whether having emotional problems, in addition to being bullied, incrementally affects the relationship between bullying and school attendance and the mitigating influence of peer friendships on these relationships. The results show gender differences in which absenteeism associated with bullying was mitigated by the support of friends for boys but not to the same degree for girls, especially those girls who had reported being psychologically bullied. Our findings suggest a school environment in which peer friendship and emotional wellbeing are intertwined in complex ways.

A field test was performed in El Salvador to evaluate the usefulness of the Shape&Roll prosthetic foot, a foot developed for low-income countries, involving 12 participants. Quantitative gait parameters were measured with a Direct Ultrasound Ranging System (DURS). Qualitative information was obtained from questionnaires administered before and after a three-week trial. The results indicate that the Shape&Roll foot widened the speed range of all participants. According to the questionnaires, the Shape&Roll foot eases walking, enabling participants to walk significantly longer distances. The participants rated its roll-over as very natural and smooth, resulting in a self-perceived reduced walking effort. Handling inclined and uneven surfaces was also rated superior to their current Solid Ankle Cushioned Heel (SACH)-like feet.

Multiple solution-state techniques have been employed in investigating the nature and control of electron transfer in the context of the proposed "domain shuffle hypothesis" for intraprotein electron transfer inferred from the crystal structure of the nitric oxide synthase reductase domain. NADPH analogues and fragments have been used to map those regions of this substrate that are important in eliciting a conformational change, observed in both the fluorescence emission of the flavin cofactors of the enzyme and the EPR spectra of the FMN flavosemiquinone state. EPR and UV-visible potentiometric methods have demonstrated a substantial calmodulin-dependent perturbation in the midpoint reduction potentials of the redox couples of both flavin cofactors, in contrast to a previous report [Noble, M. A., et al. (1999) Biochemistry 38, 16413-16418]. These studies support a model in which FMN domain mobility, triggered by Ca2+-calmodulin binding and antagonized by substrate binding, facilitates electron transfer in nitric oxide synthase through conformational change and effects a major change in the midpoint reduction potentials of the flavin redox couples. These results are discussed in light of the recent crystal structure of the NADPH-locked reductase domain.

This panel explores the "state of the art" in conceptualization and research pertinent to program quality in substance user treatment. First, seven critical questions for program quality are identified and discussed. Second, a recent national evaluation of treatment examines the implications of long-term patient outcomes for treatment quality. Third, a large number of clinical trials of behavioral and pharmacological treatments for cocaine dependence were conducted during the 1990s; this research is synthesized and interpreted. Fourth, progress is reported in improving the quality of treatment through standardized criteria for patient placement matching.