Using the Frobenius series method (FSM), an analytical solution is developed to obtain mechanical stresses of thick spherical pressure vessels made of functionally graded materials (FGMs). The cylinder pressure vessel is subjected to uniform internal pressure. The modulus of elasticity is graded along the radial direction according to power functions of the radial direction. It is assumed that ...

Sixteen patients, 10 with significant three-vessel coronary artery disease (>50% occlusion of each vessel) and six without coronary disease, had nutrient myocardial blood flow, cardiac output, pressure time/ min and arterial pressure determinations at rest, with atrial pacing and with right atrial pacing plus nitroglycerin. In the patients with coronary disease, nutrient myocardial blood decrea...

The quasi-static mechanical properties of the aorta of Octopus dofleini were investigated using biaxial inflation and uniaxial force-extension tests on vessel segments in vitro. The octopus aorta is a highly compliant and non-linearly elastic structure. The elastic modulus (i.e. the stiffness) measured circumferentially (Ec) and longitudinally (EL) increased markedly with distension of the vess...

Sixteen patients, 10 with significant three-vessel coronary artery disease (>50% occlusion of each vessel) and six without coronary disease, had nutrient myocardial blood flow, cardiac output, pressure time/ min and arterial pressure determinations at rest, with atrial pacing and with right atrial pacing plus nitroglycerin. In the patients with coronary disease, nutrient myocardial blood decrea...

Sixteen patients, 10 with significant three-vessel coronary artery disease (>50% occlusion of each vessel) and six without coronary disease, had nutrient myocardial blood flow, cardiac output, pressure time/ min and arterial pressure determinations at rest, with atrial pacing and with right atrial pacing plus nitroglycerin. In the patients with coronary disease, nutrient myocardial blood decrea...

Introduction: The composition of the martian polar caps has long been debated with a consensus opinion that the north is composed predominately of water ice and the south a combination of solid CO2 and water ice [1]. Smythe and Miller [2] suggested that the polar caps may be composed of at least some CO2 hydrate, aka. clathrate, or compound gas hydrates [3, 4, 5, 6, 7]. Durham [8] predicted tha...

background: hypertension is considered an independent risk factor for cardiovascular mortality in diabetic patients. the present study was designed to determine the role of gamma amino butyric acid b (gabab) receptor and l-arginine (l-arg) in gaba-induced vasorelaxation in normal and streptozotocin-induced diabetic rat vessels. methods: diabetes was induced by a single i.p. injection of strepto...

BACKGROUND Coronary microvascular resistance during maximal hyperemia is generally assumed to be unaffected by percutaneous coronary interventions (PCIs). We assessed a velocity-based index of hyperemic microvascular resistance (h-MR(v)) by using prototypes of a novel, dual-sensor (Doppler velocity and pressure)-equipped guidewire before and after PCI to test this hypothesis. METHODS AND RESU...

The discharge characteristics of mechanoreceptors located in the left superior vena cava were determined in an in vitro preparation developed from the rat. Two classes of receptors with afferent fibers in the vagus were identified on the basis of their response to steps of pressure. Slowly adapting receptors (n = 18) discharged as long as pressure was above threshold and exhibited a biphasic de...

This study attempted to evaluate the relative roles of vessel distensibility and vessel recruitment in the changes in pulmonary blood volume induced by changes in pulmonary intravascular pressure. Pulmonary blood volume was determined by a double-injection indicator-dilution technique in eight anesthetized open-chest dogs with a right and left ventricular bypass which allowed independent contro...