We investigated if the number and duration of breathing events coupled to upper airway collapsibility were affected by the time of day. Male participants with obstructive sleep apnea completed a constant routine protocol that consisted of sleep sessions in the evening (10 PM to 1 AM), morning (6 AM to 9 AM), and afternoon (2 PM to 5 PM). On one occasion the number and duration of breathing even...

We have previously shown that in subjects with obstructive sleep apnea, repetitive hypoxia is associated with long-term facilitation as manifested by decreased upper airway resistance (Rua). Our objective was to study the influence of long-term facilitation on upper airway collapsibility as measured by the critical closing pressure (Pcrit) model and to determine whether changes in Rua correlate...

the aim of the present study was to investigate the influence of nozzle configurations on spray drift and explain the influences using several atomization characteristics (length of spray sheet, spray angle, velocity distribution of flow field, fluctuation of velocity, and droplet size). nozzles manufactured by one company (lechler gmbh, germany) were tested by spraying local tap water in a win...

This study addressed the question of whether there are any differences in the size and collapsibility of the upper airway measured by digital fluoroscopy, between snorers and controls whilst they were awake and breathing normally; and whether there are any correlations between these measurements and other clinical data. The dynamic changes of the upper airway size were evaluated using digital f...

THE PHARYNGEAL AIRWAY IS A complicated structure combining soft tissue and boney elements that make it prone to collapse when neuromuscular activity wanes during sleep. Anatomic structures form a pliable conduit capable of changing airway patency dynamically to support its respiratory, alimentary, and vocal functions. Respiratory function is supported by active neuromuscular and passive structu...

We introduce a notion of strong d-collapsibility. Using this notion, we simplify the proof of Matoušek and the author [4] showing that the nerve of a family of sets of size at most d is d-collapsible.

microfluidic flow focusing devices have been utilized for droplet generation on account of its superior control over droplet size. droplet based microfluidics addressed many scientific issues by providing a novel technological platform for applications such as biology, pharmaceutical industry, biomedical studies and drug delivery. this study numerically investigated the droplet generation proce...

BACKGROUND Prior research suggests that the ratio of the ultrasound-measured diameter of the inferior vena cava to the aorta correlates with the level of dehydration in children. This study was designed to externally validate this and to access the accuracy of the ultrasound measured inspiratory IVC collapse and physician gestalt to predict significant dehydration in children in the emergency d...