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Atrial fibrillation is a common arrhythmia affecting thousands of individuals worldwide. It is a conduction disorder that causes the heart to beat irregularly and rapidly. There are a few medical approaches to manage this costly health care burden: antiarrhythmics to maintain normal sinus rhythm, beta blockers to achieve rate control while allowing atrial fibrillation to persist, and electro-physiologic intervention for rate and rhythm control. These treatments can be costly and are not without side effects. Yoga, an intervention that is available to people worldwide, has shown some promise in combating this widespread heart disorder. [ABSTRACT FROM AUTHOR]

Facilitating Technological Change: The Human Resource Challenge By Patricia M. Flynn. Cambridge, MA., Ballinger Publishing Co., 1988. 233 pp. This book has the ambitious task of examining the impact of [...]

Unheard Voices: Labor and Economic Policy in a Competitive World. By Ray Marshall. New York, Basic Books, 1987. 304 pp. $19.95. During the early 1980's, there were many books critical [...]

This article presents a comment on the growth of part-time employment in U.S. universities. Those who work in universities have become aware of such a phenomenon because of the dramatic trends which have shaped the academy. While the 1960s experienced the opening of one new college of university in the U.S. every week every year throughout the decade, the 1970s have witnessed the shrinking of the college-aged population and the non-growth or contraction of enrollments. As most faculty joined the ranks since 1960, there allegedly is a modest attrition by death and retirement, resulting to few new positions in university facilities. Apparently, part-time employment does not help in the pursuit of a permanent and full-time academic career. Furthermore, there is no mention of the cost-savings approach in higher educational institutions. One point essential for the understanding of the phenomenon of part-time employment is the reality of the economy itself. The problem is that the political economy in the U.S. is shaped so that the nation is oversupplied not only with unskilled labor, but also with an educated populace.

Reviews the documentary motion picture "Working for Your Life," released on video tape.

Reviews the documentary motion picture "Hazard Recognition Training Program," released on video tape.

Reviews the documentary motion picture "Health Hazards in the Shop," released on video tape.

Reviews the documentary motion picture "The American Way of Cancer: Part II," released on video tape.

Reviews the documentary motion picture "Kepone," released on video tape.

Thrombosis is a significant issue for cardiovascular device development and use. While thrombosis models are available, very few are device-related and none have been thoroughly validated experimentally. Here, we introduce a surface adherent platelet transport equation into a continuum model to account for the biomaterial interface/blood interaction. Using a rotating disc system and polyurethane-urea material, we characterize steady and pulsatile flow fields using laser Doppler velocimetry. In vitro measurements of platelet adhesion are used in combination with the LDV data to provide further experimental validation. The rotating disc system is computationally studied using the device-induced thrombosis model with the surface platelet adherent transport equation. The results indicate that the flow field is in excellent agreement to the experimental LDV data and that the platelet adhesion simulations are in good agreement with the in vitro platelet data. These results provide good evidence that this transport equation can be used to express the relationship between blood and a biomaterial if the correct platelet adhesion characteristics are known for the biomaterial. Further validation is necessary with other materials. [ABSTRACT FROM AUTHOR]

The closing behavior of mechanical heart valves is dependent on the design of the valve and its housing, the valve composition, and the environment in which the valve is placed. One innovative approach for improving the closure dynamics of tilting disk valves is introduced here. We transformed a normal Delrin occluder into one containing a "dynamic liquid core" to resist acceleration and reduce the moment of inertia, closing velocity, and impact forces of the valve during closure. The modified occluder was studied in the mitral position of a simulation chamber under the physiologic and elevated closing conditions of 2500 mm Hg/s and 4500 mm Hg/s, respectively. Cavitation energy, detected as high-frequency pressure transients with a hydrophone, was the measure used to compare the modified valve with its unaltered counterpart. The cavitation potential of tilting disk valves is indicative of the extent of blood damage occurring during valve closure. Initial findings suggest that changes to the structure or physical properties of well established mechanical valves, such as the one described here, can reduce closure induced hemolysis by minimizing cavitation. Compared with a normal valve, the cavitation intensity associated with our modified valve was reduced by more than 66% at the higher load. Furthermore, the modified valve took longer to completely close than did the standard tilting disk valve, indicating a dampened impact and rebound of the occluder with its housing. [ABSTRACT FROM AUTHOR]

While cardiovascular device-induced thrombosis is associated with negative patient outcomes, the convoluted nature of the processes resulting in a thrombus makes the full thrombotic network too computationally expensive to simulate in the complex geometries and flow fields associated with devices. A macroscopic, continuum computational model is developed based on a simplified network, which includes terms for platelet activation (chemical and mechanical) and thrombus deposition and growth in regions of low wall shear stress (WSS). Laminar simulations are performed in a two-dimensional asymmetric sudden expansion geometry and compared with in vitro thrombus size data collected using whole bovine blood. Additionally, the predictive power of the model is tested in a flow cell containing a series of symmetric sudden expansions and contractions. Thrombi form in the low WSS area downstream of the asymmetric expansion and grow into the nearby recirculation region, and thrombus height and length largely remain within 95 % confidence intervals calculated from the in vitro data for 30 min of blood flow. After 30 min, predicted thrombus height and length are 0.94 and 4.32 (normalized by the 2.5 mm step height). Importantly, the model also correctly predicts locations of thrombus deposition observed in the in vitro flow cell of expansions and contractions. As the simulation results, which rely on a greatly reduced model of the thrombotic network, are still able to capture the macroscopic behavior of the full network, the model shows promise for timely predictions of device-induced thrombosis toward optimizing and expediting the device development process. [ABSTRACT FROM AUTHOR]

Reviews the documentary motion picture "No Easy Way: A Union Safety and Health Committee in Action," released on video tape.

Reviews the documentary motion picture "Worker to Worker."

Reviews the video tape "Asbestos: Fighting a Killer."

Reviews the documentary motion picture "Another Day's Living," released on video tape.

Reviews the documentary motion picture "Can't Take No More."

Reviews the documentary motion picture "OSHA."

Reviews the documentary motion picture "More Than a Paycheck."

Reviews the documentary motion picture "The Shop Accident: Employee Rights Under the OSHAct (1970)," released on video tape.

Reviews the documentary motion picture "Working Steel," released on video tape.

Reviews the documentary motion picture "Safety in Shipbuilding," released on video tape.