Flow-injection manifolds are described which allow the preconcentration of lead for flame atomic absorption determinations, using columns contained within the sample loop of an injection valve. An interface was designed which allowed the valves and pump in the system to be controlled by an autosampler which enabled precise timing of preconcentration and elution steps. The effects of sample flow...

Normal heart function is critically dependent on the timing and coordination provided by a complex network of specialized cells: the cardiac conduction system. We have employed functional assays in zebrafish to explore early steps in the patterning of the conduction system that previously have been inaccessible. We demonstrate that a ring of atrioventricular conduction tissue develops at 40 hou...

Vitamin k Antagosnist Oral Anticoagulants (VKA) are effective in the primary and secondary prevention of venous thromboembolism, in the prevention of systemic embolism and stroke in patients with prosthetic heart valves or atrial fibrillation. In patients with thromboembolic disease Low Molecular Weight Heparin (LMWH) and oral VKA are started at diagnosis. LMWH is than stopped once the Internat...

Increased destruction of red blood cells follows the insertion of ball valves into the heart in most cases. Usually, hemolysis is slight, but in some patients uncompensated hemolytic anemia develops. To study the influence on hemolysis of the mechanical properties of the prostheses, the degree of erythrocyte destruction was evaluated in patients with Starr-Edwards aortic prostheses of different...

This study addressed the following questions: 1) Does cyclic tensile strain induce protein expression patterns consistent with myxomatous degeneration in mitral valves? 2) Does cyclic strain induce local serotonin synthesis in mitral valves? 3) Are cyclic strain-induced myxomatous protein expression patterns in mitral valves dependent on local serotonin? Cultured sheep mitral valve leaflets wer...

Increased destruction of red blood cells follows the insertion of ball valves into the heart in most cases. Usually, hemolysis is slight, but in some patients uncompensated hemolytic anemia develops. To study the influence on hemolysis of the mechanical properties of the prostheses, the degree of erythrocyte destruction was evaluated in patients with Starr-Edwards aortic prostheses of different...

Holter's invention of the non-retum valve and its use in ventriculo-caval drainage operations has been a revolutionary step in the treatment of hydrocephalus. The valves effectively control intracranial pressure and prevent the back flow of blood from the vascular system. This technique has been in use in this country since January 1958. In our unit 48 such operations were carried out during 19...

We address the control of the airpath of a turbocharged S.I. engine equipped with Variable Valve Timing actuators (VVT). Compared to standard configurations, the engine does not possess any external EGR (Exhaust Gas Recirculation) loop. Rather, VVT are used to produce internal EGR, providing similar beneficial effects in terms of emissions reduction. The airpath dynamics takes the form of a sin...

During the past decade, single gene disruption in mice and large-scale mutagenesis screens in zebrafish have elucidated many fundamental genetic pathways that govern early heart patterning and differentiation. Specifically, a number of genes have been revealed serendipitously to play important and selective roles in cardiac valve development. These initially surprising results have now converge...