BACKGROUND AND PURPOSE We compared relative changes in middle cerebral artery velocity and internal carotid artery flow during autoregulation testing to test the validity of using transcranial Doppler recordings of middle cerebral artery velocity to evaluate cerebral autoregulation in humans. METHODS Seven human volunteers had dynamic autoregulation tested during surgical procedures that incl...

1024x768 normal 0 false false false en-us x-none ar-sa background and objective: numerical modeling of biological structures would be very helpful tool to analyze hundreds of human body phenomena and also diseases diagnosis. one physiologic phenomenon is blood circulatory system and heart hemodynamic performance that can be simulated by utilizing lumped method. in this study, we can predict hem...

The possibility of employing internal wall as mass absorber in rectangular water storage tanks subjected to harmonic ground motion excitation is investigated in this paper. Internal walls are used in these tanks usually for service performance purposes, which could be used as mass absorber to control seismic demand on tank's exterior walls. Derivation of the response of the coupled system inclu...

BILATERAL ligation of the internal mammary arteries was proposed by Fieschi as a simple surgical means of treating patients with coronary artery disease. The procedure aims to increase the blood pressure in the pericardiophrenic branches of the internal mammary arteries and, thereby enhancing coronary anastomoses to the myocardium. Observations made on patients have been conflicting,' as have t...

BACKGROUND The aim of the present study was to determine the respective influences of local pulse pressure and mean blood pressure on arterial remodeling in humans at 2 arterial sites: a central, predominantly elastic artery (the common carotid artery) and a peripheral muscular artery (the radial artery). METHODS AND RESULTS Forty-three healthy subjects and 124 never-treated hypertensive pati...

Retinal artery pressure was measured by ophthalmodynamometry in 15 patients with occlusion of the internal carotid artery in its extracranial part. Nine of the patients had severe neurological deficit whereas the remaining six had slight or intermittent symptoms. Retinal artery pressure was reduced on the side of the internal carotid artery occlusion in all patients studied. Near-zero low diast...

In this study, the energy release rates in a centrally perforated star-shaped disk, which was made of a polymeric material, under internal pressure and thermal loads, were determined. The deformations of the disk were constrained by a circular steel ring enclosing the disk. Two constitutive models, namely, Hookean model and Ogden model, were used to model the constitutive behavior of the materi...

BACKGROUND AND PURPOSE Measuring blood pressure (stump pressure) in the distal internal carotid artery during occlusion of the internal carotid artery is reportedly a reliable safety index with which to predict ischemia following permanent occlusion of the internal carotid artery. We compared the stump pressure during occlusion of the internal carotid artery with single-photon emission CT (SPEC...

Under high pressure, the phase transition mechanism and mechanical property of material are supposed to be largely associated with the transformation induced elastic strain. However, the experimental evidences for such strain are scanty. The elastic and plastic properties of ZnO, a leading material for applications in chemical sensor, catalyst, and optical thin coatings, were determined using i...