Increasing lung volume improves upper airway airflow dynamics via passive mechanisms such as reducing upper airway extraluminal tissue pressures (ETP) and increasing longitudinal tension via tracheal displacement. We hypothesized a threshold lung volume for optimal mechanical effects on upper airway airflow dynamics. Seven supine, anesthetized, spontaneously breathing New Zealand White rabbits ...

Objectives To assess breathing behaviors and perception of added respiratory loads in young compared to old individuals, and to determine whether aging affects the perception and response to changes in nasal airway resistance. Study design In a clinical study, 40 young (11-20 years) and 40 older (59-82 years) subjects were evaluated during rest breathing and during the application of added ai...

Twenty-eight greenhouse screening materials, with predetermined airflow resistance values, were evaluated for exclusion of the silverleaf whitefly Bemisia argentifolii Perring & Bellows and thrips from a mixed-species population. Screens differed in exclusion efficacy, expressed as a percentage of the fiberglass window screen control and at an approach velocity of 92 m/min, from -35 to 94% for ...

Correct inhalation technique is essential for effective use of dry powder inhalers (DPIs), as their effectiveness largely depends on the patient's inhalation manoeuvre. Children are an especially challenging target population for DPI development due to the large variability in understanding and inspiratory capacities. We previously performed a study in which we determined the prerequisites for ...

BACKGROUND Potentially infected individuals ('source') are sometimes encouraged to use face masks to reduce exposure of their infectious aerosols to others ('receiver'). To improve compliance with Respiratory Source Control via face mask and therefore reduce receiver exposure, a mask should be comfortable and effective. We tested a novel face mask designed to improve breathability and filtratio...

IMPORTANCE Collapse or compromise of the internal nasal valve (INV) results in symptomatic nasal obstruction; thus, various surgical maneuvers are designed to support the INV. OBJECTIVE To determine the effect on nasal airflow after various surgical techniques focused at the level of the INV and lateral nasal sidewall. DESIGN AND SETTING A fresh cadaver head was obtained and underwent sutur...

Correct inhalation technique is essential for effective use of dry powder inhalers (DPIs), as their effectiveness largely depends on the patient’s inhalation manoeuvre. Children are an especially challenging target population for DPI development due to the large variability in understanding and inspiratory capacities. We previously performed a study in which we determined the prerequisites for ...

Satisfactory methods, utilizing measurements of transthoracic or transpulmonary pressure and airflow, are now available for determining "nonelastic" pulmonary resistance. However, the nonelastic pulmonary resistance has two components, tissue resistance and airway resistance, and no valid direct method is available for measuring either of these components separately in man. Since airway resista...