Data collected during seven population health surveys over 18 years in Busselton, Western Australia, were examined to determine the effect of smoking on lung function and to investigate the development of chronic airflow limitation. Lung function was measured and details of respiratory illness and smoking histories were collected from subjects attending surveys at three year intervals from 1966...

The physiological mechanisms by which vibration and other physiotherapy interventions may clear secretions in subjects with cystic fibrosis are unknown. The main aim of this study was to compare the expiratory flow rates and frequencies of airflow oscillation of vibration to those of Acapella(R), Flutter(R), positive expiratory pressure and percussion. Respiratory flow rates were measured durin...

Use of a portable HEPA filter cleaner in a room is believed to be capable of reducing the risk of transmission of infectious diseases through removing the particles or large droplets to which pathogens are attached. It is hoped that the portable HEPA filter(s) can increase the effective air change rate (for particle removal only) in a general ward to the ventilation standard of an isolation war...

PURPOSE OF REVIEW Irreversible airflow limitation develops in some patients with asthma and is related to poorer prognosis. This paper reviews recent literature on natural course, risk factors, and potential mechanisms of persistent airflow limitation in asthma. RECENT FINDINGS The natural course of persistent airflow limitation in asthma is poorly known, but reduced lung function at disease ...

BACKGROUND Alpha1 anti-trypsin (α1-AT), a serine protease inhibitor synthesized in the liver, is a major circulating antiprotease that provides defense against proteolytic damage in several tissues. Its deficiency is associated with airflow obstruction. The present study aimed to explore the role of α1-AT as a biomarker of airflow performance in chronic liver disease (CLD). MATERIAL/METHODS S...

[1] Most analytical and numerical models developed to analyze pumping test data focus on saturated flow below the water table. Traditionally the soil above the initial water table prior to pumping has been thought to have little influence on the test results and has usually been ignored. It is hypothesized that, if the unsaturated zone is capped by low-permeability soil, airflow in the unsatura...

BACKGROUND Facial coverings (e.g., balaclavas, niqabs, medical/surgical masks, respirators, etc.), that impose low levels of airflow resistive loads, are worn by millions of pregnant women worldwide, but little data exist addressing their impact on pregnancy-associated cardiovascular and pulmonary responses. METHODS 16 pregnant and 16 non-pregnant women were monitored physiologically (heart r...

Background: Chronic obstructive pulmonary disease (COPD) is a syndrome of chronic progressive airflow limitation which occurs as a result of chronic inflammation of the airways and lung parenchyma. However, the role of inhaled corticosteroids in the treatment of COPD is controversial. We hypothesised that inhaled corticosteroids reduce the progression of airflow limitation in COPD. Methods: A c...

An energy model that correlates fan airflow, head, speed, and system power input is essential to detect device faults optimize control strategies in systems. Since the application of variable-frequency drives (VFDs) makes motor-efficiency data published by manufacturers inapplicable for VFD–motor–fan systems, efficiency drive (belt–motor–VFD) must be identified each individual obtain accurate m...

Strong acid solutions have been widely used in acid traps to determine concentrations of ammonia in ambient air or exhaust air stream. A literature survey indicates the method has a long history and a wide variation in use. Through a series of studies, this paper examines several factors including volume of the acid, depth of the acid, and airflow rate; that might affect the efficiency of sulfu...