Solid exchange between the bubble wake and the emulsion phase in a gas-fluidised bed was studied both experimentally and theoretically. Measurements were made on the tracer particle concentration profile produced after a single bubble passage in a two-dimensional bed, and the solid exchange coefficients were estimated with the results of simultaneous measurements on the shape, the size and the ...

An intravenous respiratory support catheter, the next generation of artificial lungs, is being developed in our laboratory to potentially support acute respiratory failure or patients with chronic obstructive pulmonary disease with acute exacerbations. A rapidly pulsating 25 ml balloon inside a bundle of hollow fiber membranes facilitates supplemental oxygenation and CO2 removal. In this study,...

The capacity to perform gas exchange with the environment is an evolutionary milestone of terrestrial development. The lung has undergone extensive alterations during evolution to acquire a large surface area to efficiently perform gas exchange between the oxygen-rich environment and the cardiovascular system. A process called branching morphogenesis has been used by the respiratory system to e...

BACKGROUND Etorphine, a potent opioid agonist, causes pulmonary hypertension and respiratory depression. Whether etorphine-induced pulmonary hypertension negatively influences pulmonary gas exchange and exacerbates the effects of ventilator depression and the resultant hypoxemia is unknown. To determine if these effects occurred we instrumented twelve goats with peripheral and pulmonary arteria...

Thermal tolerance has been hypothesized to result from a mismatch between oxygen supply and demand. However, the generality of this hypothesis has been challenged by studies on various animal groups, including air-breathing adult insects. Recently, comparisons across taxa have suggested that differences in gas exchange mechanism could reconcile the discrepancies found in previous studies. Here ...

Objectives: Video-assisted thoracoscopic surgery (VATS) is generally recognized as a less invasive method than thoracotomy. However, the in ̄uence of VATS on postoperative pulmonary gas exchange has yet to be evaluated. Methods: Thirty eight patients with spontaneous pneumothorax were randomized into bullectomy by VATS (n ˆ 20) or axillary thoracotomy (n ˆ 18). Gas exchange was assessed by using...

We have implemented gas-phase hydrogen/deuterium exchange (HDX) experiments in the external collision cell of a hybrid quadrupole-Fourier transform ion cyclotron resonance mass spectrometer. In this configuration, multiply charged oligonucleotide anions undergo significant exchange with D(2)S at reaction intervals ranging from 0.11 to 60.1 s. For DNA homohexamers, relative exchange rates were d...

Photosynthetic gas exchange and malic acid fluctuations were monitored in 69 well-watered plants from five morphologically similar species of Talinum in an investigation of the ecophysiological significance of the Crassulacean acid metabolism (CAM)-cycling mode of photosynthesis. Unlike CAM, atmospheric CO(2) uptake in CAM-cycling occurs exclusively during the day; at night, the stomata are clo...

Thermal tolerance has been hypothesized to result from a mismatch between oxygen supply and demand. However, the generality of this hypothesis has been challenged by studies on various animal groups, including air-breathing adult insects. Recently, comparisons across taxa have suggested that differences in gas exchange mechanisms could reconcile the discrepancies found in previous studies. Here...