Background: During operation of a jet nebulizer, the temperature of the nebulizer outlet could decrease by more than 10 degrees C, depending on the nebulizer type and operating conditions, such as driving flow rate and fill volume. The droplet size distribution generated from the nebulizer can be measured by a cascade impactor. However, when the cascade impactor is operated at ambient room temperature, the droplets could evaporate because of the temperature difference between the nebulizer outlet and the body of the impactor.
Methods: An 8-stage cascade impactor was used to measure the particle size distribution from 4 different types of jet nebulizer (LC Plus, Side-Stream, VixOne, and Micromist) in 2 temperature conditions: ambient (22 degrees C) and low (10 degrees C). Two different formulations, albuterol (aqueous solution) and budesonide (suspension), were used.
Results: There was a significantly larger (p < 0.05) mass median aerodynamic diameter and smaller respirable fraction for each nebulizer with the impactor at low temperature than with the impactor at ambient temperature. The mass median aerodynamic diameter of the nebulizers with the impactor operating at low temperature appeared 15-130% larger than with the impactor operating at ambient temperature, for both formulations. The respirable fraction also changed from 10% when the impactor was operated at low temperature to 65% when the impactor was operated at ambient temperature.
Conclusion: The results provide important information for the use of a cascade impactor to measure the particle-size distribution of nebulizer aerosols.
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Sci Total Environ
December 2024
Department of Civil and Environmental Engineering, Universidad del Norte, Barranquilla, Colombia. Electronic address:
This study assessed the prevalence and spatial distribution of viable ultrafine and fine antibiotic-resistant bacteria aerosols (ARB) in the Metropolitan Area of Barranquilla, Colombia, pre- and post-lockdown (September 2019 to December 2020). Samples were systematically collected from urban, suburban, and rural sites using a six-stage viable cascade impactor. We employed logistic regression and Bayesian Neural Network Classifiers to analyze meteorological variables' influence on antibiotic resistance persistence.
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Department of Environmental Engineering, Eskişehir Technical University, Eskişehir 26555, Türkiye.
Inhalable micro(nano)plastics (MNPs) have emerged as a significant global concern due to their abundance and persistence in the atmosphere. Despite a growing body of literature addressing the analytical requirements of airborne MNPs, the issue of inhalable fractions and analysis of slotted substrates remains unclear. Therefore, the objective of this study is to perform a systematic particle-based analysis and characterization of inhalable microplastics (MPs) collected by a high-volume sampler equipped with a five-stage cascade impactor with a size range of 10 μm to <0.
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Max-Planck-Institut für Astronomie, Heidelberg, Germany.
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School of Pharmacy, Faculty of Health & Medical Sciences, Taylor's University, Subang Jaya, Malaysia; Digital Health and Medical Advancements Impact Lab, Taylor's University, Subang Jaya, Malaysia.
Zerumbone (ZER), a compound derived from the rhizome of Zingiber Zerumbet (L.) Smith, has demonstrated anti-inflammatory properties but suffers from poor water solubility, limiting its clinical application. While ZER's effects on lung inflammation are known, its role in lung fibrosis remains unexplored.
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Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Eötvös Street 6, 6720 Szeged, Hungary.
Cystic fibrosis is a hereditary disease, which causes the accumulation of dense mucus in the lungs accompanied by frequent local inflammation. The non-steroidal anti-inflammatory drug ibuprofen (IBU) and the mucolytic mannitol (MAN) can treat these symptoms. Compared to per os administration, a lower dose of these drugs is sufficient to achieve the desired effect by delivering them in a pulmonary manner.
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