We outline methodologies for computation of the spatial distributions of energy-optimal linear initial and boundary disturbances to incompressible flows. The theory presented here is based in techniques developed for constrained optimisation, but we show that there are equivalent eigenvalue interpretations. As a result the computations may be carried out either by optimisation or eigensystem me...

While a number of electrolytes play a role in the genesis of the transmembrane action potential (AP), the changes in the action potential most clearly related to arrhythmias are dependent to a large extent on K+. Potassium gradient is a major determinant of the magnitude of transmembrane resting potential (TRP), and secondarily the rate of rise (dV/dt) of phase 0, and consequently the speed of ...

Coupling intervals of extrastimuli that induced 57 previously documented unimorphic ventricular tachycardias (VTs) were compared with coupling intervals that induced 57 episodes of polymorphic VT or ventricular fibrillation (VF) in patients wlthout a documented or suspected history of polymorphic VT or VF. Programmed stimulation was performed with the patient in the drug-free state, with 1 to 3...

Approximately 90% of the population-attributable risk for coronary artery disease has been estimated to relate to 9 potentially modifiable risk factors, including tobacco smoking, overweight, dyslipidemia, hypertension, physical inactivity, poor diet, and psychosocial factors.1 Accordingly, published guidelines for primary and secondary cardiovascular disease prevention support aggressive risk ...

Hypocirculation causes hypercoagulability with an increase of Factors V and VIII, and a diminished platelet count. In shock hypercoagulability is followed by hypocoagulability due to loss of Factors I, II, V, VIII and XIII together with thrombocytopaenia and qualitative alterations in platelet properties. This reversal is caused by disseminated intravascular coagulation consuming clotting facto...

Ponderosa pine (Pinus ponderosa P. & C. Lawson) is highly suitable for management using multiaged systems. This suitability is primarily the result of a frequent, low severity disturbance regime, but also because it naturally occurs at low densities and has a long history of management to promote multiple age classes. Several different stocking control tools are available for ponderosa pine inc...

The longstanding assumption has been that positive emotions and associated feelings are entirely adaptive. As a result, less scientific attention has been devoted to understanding the ways in which positive emotions might also be a source of dysfunction for our psychological health. However, the empirical tides have recently begun to change, and with it, a new wave of research has pointed to wa...

Recent technological advances have provided many youth with daily, almost continuous cell-phone and Internet connectivity through portable devices. Young people's experiences with computer-mediated communication (CMC) and their views about how this form of communication affects their health have not been fully explored in the scientific literature. A purposeful maximum variation sample of young...

This paper presents a new application of High Voltage Direct Current (HVDC) link to stabilization of frequency oscillations in a parallel AC-DC interconnected power system. When an interconnected AC power system is subjected to a large load with rapid change, system frequency may be considerably disturbed and becomes oscillatory. By utilizing the system interconnections as the control channels ...

In a liquid containing gas bubbles the speed of sound is less tham that in each phase separately. Using the equations of motion for a hõmogeneous liquid containing gas bubbles it is shown that the dominating attenuation of an infinitesimal disturbance is that due to the second viscosity. In the propagation of a finite compressive disturbance an expression for the time required for the disturban...