In the near-weightless environment of orbiting spacecraft capillary forces dominate interfacial flow phenomena over unearthly large length scales. In current experiments aboard the International Space Station, partially open channels are being investigated to determine critical flow rate-limiting conditions above which the free surface collapses ingesting bubbles. Without the natural passive ph...

bed in which we deduce that hydrostatic pressure is elevated. In the newborn lamb, the results suggest a lower capillary pressure and larger capillary bed than in the fetus. The pulmonary vascular bed of the fetus, we conclude, may contain large unperfused areas; and vasodilation at birth may take place mainly by recruitment of additional areas. There is support for these ideas in the very nonl...

In contrast to young growing animals, pressure-overload hypertrophy in adults is frequently associated with diminished myocardial capillary density and maximal coronary flow per gram. To determine the role of angiogenesis in maintaining perfusion capacity in the hypertrophying heart, the angiogenesis inhibitor protamine sulfate was administered to young lambs during the development of left vent...

In contrast to young growing animals, pressure-overload hypertrophy in adults is frequently associated with diminished myocardial capillary density and maximal coronary flow per gram. To determine the role of angiogenesis in maintaining perfusion capacity in the hypertrophying heart, the angiogenesis inhibitor protamine sulfate was administered to young lambs during the development of left vent...

To define the role of capillaries in the control of coronary blood flow (CBF) reserve, we developed a model of the coronary circulation and evaluated experimental data in its context. Our model comprised three compartments connected in series (arterial, capillary, and venous), each with its own resistance. The resistance in each vascular compartment was derived from the model based on hemodynam...

We present an in vivo method for analyzing the distribution kinetics of physiological markers into their respective distribution volumes utilizing information provided by the relative dispersion of transit times. Arterial concentration-time curves of markers of the vascular space [indocyanine green (ICG)], extracellular fluid (inulin), and total body water (antipyrine) measured in awake dogs un...

Effects of chronic hypoxia on hemodynamic response to sensory stimulation were investigated. Using laser-Doppler flowmetry, change in cerebral blood flow (CBF) was measured in awake mice, which were housed in a hypoxic chamber (8% O₂) for 1 month. The degree of increase in CBF evoked by sensory stimulation was gradually decreased over 1 month of chronic hypoxia. No significant reduction of incr...

Because pulmonary arteries are end arteries, the circulation within the lung once appeared to be simple. However, an increasing amount of information concerning the systemic contribution to this circulation, mainly through bronchopulmonary anastomoses, has made the picture complex. The intricate network that the bronchial vessels establish between the aorta and the pulmonary arteries on the one...

A critical indicator of tissue viability and function is blood delivery to the capillary bed (referred to as perfusion or tissue/capillary blood flow), so the measurement of this process has been pursued by many MR scientists. Perfusion MRI is currently an effective tool to non-invasively quantify cerebral blood flow (CBF) and to easily obtain its relative change due to neural activity or other...