IOH (initial orthostatic hypotension) comprises symptoms of cerebral hypoperfusion caused by an abnormally large transient MAP (mean arterial pressure) decrease 5-15 s after arising from a supine, sitting or squatting position. Few treatment options are available. In the present study, we set out to test the hypothesis that LBMT (lower body muscle tensing) attenuates IOH after rising from squat...

Objectives To determine the feasibility of assessing population cardiovascular risk with advanced hemodynamics in the Healthy Life in Suriname (HELISUR) study. Methods This was a preliminary study conducted in May - June 2012 using the Technical-Economic-Legal-Operational-Scheduling (TELOS) method to assess the feasibility of the HELISUR-a large-scale, cross-sectional population study of card...

OBJECTIVE To examine cardiovascular reactivity and recovery to laboratory stress among a naturalistic sample of individuals diagnosed with major depressive disorder (MDD) and healthy control participants. Prospective evidence suggests that MDD confers risk for cardiovascular disease equal to or greater than the risk associated with depressed mood. Enhanced cardiovascular reactivity has been pro...

This study aimed to examine the effect of caffeine on hemodynamics after a resistance exercise session. Fifteen subjects completed two randomly ordered experimental resistance exercise sessions 45 min after the ingestion of either caffeine (4 mg.kg(-1)) or placebo. Systolic (SBP), diastolic (DBP) and mean (MAP) blood pressures were measured before consuming caffeine; SBP, DBP, MAP, heart rate, ...

Cocaine or air jet stress evokes pressor responses due to either a large increase in systemic vascular resistance (vascular responders) or small increases in both cardiac output and vascular resistance (mixed responders) in conscious rats. Repeated cocaine administration results in elevated arterial pressure in vascular responders but not in mixed responders. The present study examined the hypo...

This paper presents a systematic approach to designing negative-resistance and Colpitts oscillators using p-HEMT transistor. Various models such as, common source and common gate configuration in negative-resistance oscillators, common source series feedback in Colpitts oscillator is selected to analyze the output power and stability presented by the p-HEMT transistor. These oscillators are des...

The traditional implementation of resonant tunneling diodes (RTD) as a high-frequency power source always requires the utilization of negative-differential resistance (NDR). However, there are inherent problems associated with effectively utilizing the two-terminal NDR gain to achieve significant levels of output power. This paper will present a new design methodology where resonant tunneling s...

1. Plasma renin concentration, intra-arterial pressure, cardiac output and total peripheral resistance have been studied in 50 patients with essential hypertension and normal renal function. 2. Total peripheral resistance and plasma renin were negatively correlated (r = -0-45), indicating that 'high-renin' essential hypertension is not necessarily associated with arteriolar vasoconstriction. 3....

Previous studies have concluded that polycythemia decreases oxygen delivery primarily because of a large fall in cardiac output associated with a rise in systemic vascular resistance that has been attributed to increased blood viscosity. However, because other studies have shown that polycythemia may not reduce oxygen delivery, an alternative hypothesis is that cardiac output falls in response ...

Oral administration of 10mg. of Bay-a 1040, a new coronary dilator, produced a marked reduction of arterial pressure which was associated with a consistent decrease in peripheral vascular resistance and an increase in cardiac output and stroke volume. Changes in heart rate and left ventricular work were variable. In 20 hypertensive patients treated with the drug in doses of 10mg. per day, a mod...