BACKGROUND Responses of cerebral blood flow to the postural unloading maneuver in aortic stenosis (AS) have not been described so far. Our aim was to assess effects of orthostatic stress test on changes of carotid and vertebral artery blood flow and transaortic gradients. METHODS From consecutive 101 AS patients we selected 50 patients with severe isolated AS. Maximal and mean transaortic pre...

The hypothesis that upright posture could modulate forearm blood flow (FBF) early in exercise was tested in six subjects. Both single (2-s duration) and repeated (1-s work/2-s rest cadence for 12 contractions) handgrip contractions (12 kg) were performed in the supine and 70° head-up tilt (HUT) positions. The arm was maintained at heart level to diminish myogenic effects. Baseline brachial arte...

Pressure can retrain the heat-induced aggregation and dissociate the heat-induced aggregates. We observed the aggregation-preventing pressure effect and the aggregatesdissociating pressure effect to characterize the heat-induced aggregation of equine serum albumin (ESA) by FT-IR spectroscopy. The results suggest the -helical structure collapses at the beginning of heat-induced aggregation thro...

STUDY DESIGN Prospective, randomised controlled, single centre study of 45 patients posted for two level lumbar fixation surgery in the prone position. PURPOSE To compare intra-abdominal pressure (IAP), mean airway pressure mean airway pressure and blood loss during the spine surgery in prone position using three different positioning systems. OVERVIEW OF LITERATURE Studies have correlated ...

Experiments were conducted to evaluate the performance of a low heat rejection (LHR) diesel engine. Performance parameters and emission levels were determined at various magnitudes of brake mean effective pressure. Combustion characteristics of the engine were measured with TDC (top dead centre) encoder, pressure transducer, console and special pressure-crank angle software package at peak load...

BACKGROUND The waveform morphology of intracranial pressure pulses (ICP) is an essential indicator for monitoring, and forecasting critical intracranial and cerebrovascular pathophysiological variations. While current ICP pulse analysis frameworks offer satisfying results on most of the pulses, we observed that the performance of several of them deteriorates significantly on abnormal, or simply...

With the increasing use of solar photovoltaics, wind-induced loads on rooftop solar arrays have become a problem. A series of wind tunnel experiments have been performed to evaluate wind loads on solar panels on flat roofs, mainly focusing on their area-averaged characteristics such as mean and negative peak force coefficients, and peak factors. Solar array models were fabricated with pressure ...

PURPOSE To distinguish 24-hour (circadian) and postural effects on intraocular pressure (IOP) in healthy young adults. METHODS Thirty-three volunteers were housed in a sleep laboratory for 1 day under a strictly controlled 16-hour light and 8-hour dark environment. Sleep was encouraged in the dark period. Intraocular pressure was measured in each eye every 2 hours using a pneumatonometer. Res...