background: asphalt workers are exposed to dangerous agents in his workplace that might result in occupational diseases. benzo (a) pyrene as a human carcinogen, is emission from hot asphalt and asphalt workers are exposed with it. the aim of this study was, evaluation of respiratory exposure to benzo (a) pyrene among asphalt workers. method: in this study, 42 samples were collected from breathi...

9 10 Ozone is a major pollutant of indoor air. Many studies have demonstrated the adverse health effect of 11 ozone and the byproducts generated as a result of ozone-initiated reactive chemistry in an indoor 12 environment. This study developed a Computational Fluid Dynamics (CFD) model to predict the ozone 13 distribution in an aircraft cabin. The model was used to simulate the distribution of...

During maxillofacial and oral surgery the effect of three anaesthetic scavenging devices used with cuffed and non-cuffed endotracheal tubes was investigated. All the devices produced reductions in nitrous oxide concentrations in the breathing zone and peripheral air, ranging from 36% to 76%. Of the three devices evaluated, the Stellenbosch valve produced the greatest reduction in pollution comp...

The objective of this study is to assess the external and internal exposures to aromatic hydrocarbons in the cistern cleaning and cistern mechanic repair processes at a coke plant. 149 workers engaged as operators in cistern cleaning and cistern mechanic repair processes and 35 non-exposed subjects were examined. Personal analyses of the benzene, toluene, xylene isomers, ethylbenzene, PAH’s and...

BACKGROUND Nitrogen may contribute to reperfusion injury. Some studies have shown that helium as a replacement for nitrogen in breathing gas (heliox) reduces cell necrosis after ischemia/reperfusion when used in a preconditioning fashion (intermittent heliox exposure). Our aim was to test whether heliox, breathed continuously throughout the ischemic and reperfusion periods, reduced necrosis and...

This article examines the spatial variability of dust concentrations within a coal miner's breathing zone and the impact of sampling location at the cap lamp, nose, and lapel. Tests were conducted in the National Institute for Safety and Health Pittsburgh Research Laboratory full-scale, continuous miner gallery using three prototype personal dust monitors (PDM). The dust masses detected by the ...

BACKGROUND Welding is one of the most exercised industrial processes which welders are exposed to chemical and physical Hazardous agents. This study was conducted to evaluate occupational and environmental exposures to aerosols generated by welding processes in a factory. METHODS A total of 28 samples of aerosols were collected at 4 different locations including indoor, outdoor, source of wel...

Recent discoveries of tetrapod trackways in 395 Myr old tidal zone deposits of Poland (Niedźwiedzki et al. 2010 Nature 463, 43-48 (doi:10.1038/nature.08623)) indicate that vertebrates had already ventured out of the water and might already have developed some air-breathing capacity by the Middle Devonian. Air-breathing in lungfishes is not considered to be a shared specialization with tetrapods...

background and purpose: despite the high prevalence of chronic obstructive pulmonary disease, there haven,t been definite curative treatment for the disease and focus of treatment has directed towards pulmonary rehabilitation as an effective non-drug treatments. this study were performed to determine the effect of motivational abdominal breathing device on breathing pattern and dyspnea of chron...