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Pressure-driven distillation using air-trapping membranes for fast and selective water purification.Science Advances Jul 2023Membrane technologies that enable the efficient purification of impaired water sources are needed to address growing water scarcity. However, state-of-the-art engineered...
Membrane technologies that enable the efficient purification of impaired water sources are needed to address growing water scarcity. However, state-of-the-art engineered membranes are constrained by a universal, deleterious trade-off where membranes with high water permeability lack selectivity. Current membranes also poorly remove low-molecular weight neutral solutes and are vulnerable to degradation from oxidants used in water treatment. We report a water desalination technology that uses applied pressure to drive vapor transport through membranes with an entrapped air layer. Since separation occurs due to a gas-liquid phase change, near-complete rejection of dissolved solutes including sodium chloride, boron, urea, and -nitrosodimethylamine is observed. Membranes fabricated with sub-200-nm-thick air layers showed water permeabilities that exceed those of commercial membranes without sacrificing salt rejection. We also find the air-trapping membranes tolerate exposure to chlorine and ozone oxidants. The results advance our understanding of evaporation behavior and facilitate high-throughput ultraselective separations.
Topics: Distillation; Permeability; Gases; Water Purification; Membranes, Artificial
PubMed: 37450594
DOI: 10.1126/sciadv.adg6638 -
Pediatric Pulmonology Apr 2020To determine which outcome measures could detect early progression of disease in school-age children with mild cystic fibrosis (CF) lung disease over a two-year time...
OBJECTIVE
To determine which outcome measures could detect early progression of disease in school-age children with mild cystic fibrosis (CF) lung disease over a two-year time interval utilizing chest computed tomography (CT) scores, quantitative CT air trapping (QAT), and spirometric measurements.
METHODS
Thirty-six school-age children with mild CF lung disease (median [interquartile range] age 12 [3.7] years; percent predicted forced expiratory volume in 1 second (ppFEV ) 99 [12.5]) were evaluated by serial spirometer-controlled chest CT scans and spirometry at baseline, 3-month, 1- and 2-years.
RESULTS
No significant changes were noted at 3-month for any variable except for decreased ppFEV . Mucus plugging score (MPS) and QAT increased at 1- and 2-years. The bronchiectasis score (BS), and total score (TS) were increased at 2-year. All variables tested with the exception of bronchial wall thickness score, parenchymal score (PS), and ppFEV , were consistent with longitudinal worsening of lung disease. Multivariate analysis revealed baseline PS, baseline TS, and 1-year changes in BS and air trapping score were predictive of 2-year changes in BS.
CONCLUSIONS
MPS and QAT were the most sensitive indicators of progressive childhood CF lung disease. The 1-year change in the bronchiectasis score had the most positive predictive power for 2-year change in bronchiectasis.
Topics: Adolescent; Bronchi; Bronchiectasis; Child; Cystic Fibrosis; Disease Progression; Female; Forced Expiratory Volume; Humans; Male; Mucus; Multivariate Analysis; Outcome Assessment, Health Care; Radiography, Thoracic; Sensitivity and Specificity; Spirometry; Tomography, X-Ray Computed
PubMed: 31962004
DOI: 10.1002/ppul.24646 -
Japanese Journal of Radiology Feb 2023The present study aims to investigate the occurrence and severity of HRCT abnormalities in symptomatic never-smokers, passively exposed to cigarette smoke.
PURPOSE
The present study aims to investigate the occurrence and severity of HRCT abnormalities in symptomatic never-smokers, passively exposed to cigarette smoke.
MATERIALS AND METHODS
A total of 135 never-smokers with respiratory symptoms, without underlying lung disease, underwent paired inspiratory-expiratory HRCT and completed the secondhand smoking (SHS) exposure scale questionnaire. Individuals passively exposed to tobacco consisted the secondhand smoking group (SHS group) (n = 68); the remaining 67 controls were never exposed to SHS. Statistical analysis was performed using the Kolmogorov-Smirnov, x and Pearson Point-Biserial correlation tests. P < 0.05 was statistically significant.
RESULTS
HRCT findings in SHS group included bronchial wall thickening (98.5%), mild cylindrical bronchiectasis (44%), ground-glass opacities (17.6%), and mosaic attenuation pattern (53%). Air trapping occurred in 65% of expiratory scans. Differences in occurrence of findings between SHS group participants and controls were statistically significant (p < 0.0001). There was significant correlation between exposure to tobacco smoke in hours/day and in number of cigarettes/day and the presence of mosaic attenuation pattern, ground-glass opacities, cylindrical bronchiectasis and air trapping, respectively (p < 0.05). Cumulative SHS exposure in years was also strongly correlated with the presence of ground-glass opacities, mosaic attenuation pattern, cylindrical bronchiectasis, and air trapping, as well as with the frequency of respiratory symptoms (p < 0.05).
CONCLUSION
HRCT findings attributed to SHS are mostly related to airway involvement and are correlated with the duration and grade of exposure to environmental tobacco smoke. SHS followed by lifestyle adjustments should be considered in symptomatic non-smokers with such HRCT findings.
Topics: Humans; Tobacco Smoke Pollution; Lung Diseases; Bronchiectasis; Surveys and Questionnaires
PubMed: 36121625
DOI: 10.1007/s11604-022-01336-4 -
Respiratory Care May 2022The ventilatory mechanics of patients with COPD and obesity-hypoventilation syndrome (OHS) are changed when there is air trapping and auto-PEEP, which increase...
BACKGROUND
The ventilatory mechanics of patients with COPD and obesity-hypoventilation syndrome (OHS) are changed when there is air trapping and auto-PEEP, which increase respiratory effort. P measures the ventilatory drive and, indirectly, respiratory effort. The aim of the study was to measure P in subjects with COPD or OHS on treatment with positive pressure and to analyze their changes in P after treatment.
METHODS
With a prospective design, subjects with COPD and OHS were studied in whom positive airway pressure was applied in their treatment. P was determined at study inclusion and after 6 months of treatment.
RESULTS
A total of 88 subjects were analyzed: 56% were males, and the mean age of 65 ± 9 y old. Fifty-four (61%) had OHS, and 34 (39%) had COPD. Fifty (56%) had air trapping, with an initial P value of 3.0 ± 1.3 cm HO compared with 2.1 ± 0.7 cm HO for subjects who did not have air trapping = .001). After 6 months of treatment, subjects who had air trapping had similar P as those who did not: 2.3 ± 1.1 and 2.1 ± 1 cm HO, respectively = .53). In subjects with COPD, initial P was 2.9 ± 1.4 cm HO and at 6 months 2.2 ± 1.1 cm HO = .02). In subjects with OHS, initial P was 2.4 ± 1.1 cm HO and at 6 months 2.2 ± 1.0 cm HO = .28).
CONCLUSIONS
COPD and air trapping were associated with greater P as a marker of respiratory effort. A decrease in P indicates less respiratory effort after treatment.
PubMed: 35610030
DOI: 10.4187/respcare.09023 -
Insects Nov 2021House flies are the most prevalent synanthropic pest worldwide. Although they seldom reproduce in homes, they invade buildings, cause annoyance, and carry pathogens.... (Review)
Review
House flies are the most prevalent synanthropic pest worldwide. Although they seldom reproduce in homes, they invade buildings, cause annoyance, and carry pathogens. Urban pest management personnel are limited in their ability to locate and manage larval habitats, so most house fly management in urban settings focuses on adult fly suppression. Sanitation is probably the most critical component, eliminating odors that attract flies. Source reduction applies where larval habitats can be identified and eliminated. Exclusion involves keeping flies out of structures. Despite all efforts, flies will manage to enter the human environment, so exclusion includes air curtains, fans, screened windows, and doors. Ultraviolet light traps attract and immobilize, while window traps entice flies into devices that entrap them. Sticky tubes and ribbons rely on flies' inclination to land on vertical lines to entangle them in glue. Even low-tech fly swatters can play significant roles in eliminating individual flies. Timed-release aerosol pyrethrin dispensers can be effective against flies confined in enclosed spaces. Toxic baits have limited use in urban settings. Chemical suppression remains a critical component of fly IPM, essential in situations requiring immediate fly elimination.
PubMed: 34821842
DOI: 10.3390/insects12111042 -
BMC Pulmonary Medicine Jan 2024In tobacco-exposed persons with preserved spirometry (active smoking or secondhand smoke [SHS] exposure), air trapping can identify a subset with worse symptoms and... (Randomized Controlled Trial)
Randomized Controlled Trial
Effect of twice daily inhaled albuterol on cardiopulmonary exercise outcomes, dynamic hyperinflation, and symptoms in secondhand tobacco-exposed persons with preserved spirometry and air trapping: a randomized controlled trial.
BACKGROUND
In tobacco-exposed persons with preserved spirometry (active smoking or secondhand smoke [SHS] exposure), air trapping can identify a subset with worse symptoms and exercise capacity. The physiologic nature of air trapping in the absence of spirometric airflow obstruction remains unclear. The aim of this study was to examine the underlying pathophysiology of air trapping in the context of preserved spirometry and to determine the utility of bronchodilators in SHS tobacco-exposed persons with preserved spirometry and air trapping.
METHODS
We performed a double-blinded placebo-controlled crossover randomized clinical trial in nonsmoking individuals at risk for COPD due to exposure to occupational SHS who had preserved spirometry and air trapping defined as either a residual volume-to-total lung capacity ratio (RV/TLC) > 0.35 or presence of expiratory flow limitation (EFL, overlap of tidal breathing on maximum expiratory flow-volume loop) on spirometry at rest or during cardiopulmonary exercise testing (CPET). Those with asthma or obesity were excluded. Participants underwent CPET at baseline and after 4-week trials of twice daily inhalation of 180 mcg of albuterol or placebo separated by a 2-week washout period. The primary outcome was peak oxygen consumption (VO) on CPET. Data was analyzed by both intention-to-treat and per-protocol based on adherence to treatment prescribed.
RESULTS
Overall, 42 participants completed the entire study (66 ± 8 years old, 91% female; forced expiratory volume in 1 s [FEV] = 103 ± 16% predicted; FEV to forced vital capacity [FVC] ratio = 0.75 ± 0.05; RV/TLC = 0.39 ± 0.07; 85.7% with EFL). Adherence was high with 87% and 93% of prescribed doses taken in the treatment and placebo arms of the study, respectively (P = 0.349 for comparison between the two arms). There was no significant improvement in the primary or secondary outcomes by intention-to-treat or per-protocol analysis. In per-protocol subgroup analysis of those with RV/TLC > 0.35 and ≥ 90% adherence (n = 27), albuterol caused an improvement in peak VO (parameter estimate [95% confidence interval] = 0.108 [0.014, 0.202]; P = 0.037), tidal volume, minute ventilation, dynamic hyperinflation, and oxygen-pulse (all P < 0.05), but no change in symptoms or physical activity.
CONCLUSIONS
Albuterol may improve exercise capacity in the subgroup of SHS tobacco-exposed persons with preserved spirometry and substantial air trapping. These findings suggest that air trapping in pre-COPD may be related to small airway disease that is not considered significant by spirometric indices of airflow obstruction.
Topics: Aged; Female; Humans; Male; Middle Aged; Albuterol; Exercise; Forced Expiratory Volume; Lung; Pulmonary Disease, Chronic Obstructive; Spirometry; Vital Capacity
PubMed: 38245665
DOI: 10.1186/s12890-023-02808-7 -
Acta Radiologica (Stockholm, Sweden :... Apr 2023High-resolution computed tomography (HRCT) scans can help identify subsets of asthma patients who show rapid decline in lung function.
BACKGROUND
High-resolution computed tomography (HRCT) scans can help identify subsets of asthma patients who show rapid decline in lung function.
PURPOSE
To evaluate high-resolution computed tomography (HRCT) findings in adult patients with asthma, obtain quantitative measurements of air trapping on expiratory scans, and correlate the findings with pulmonary function tests (PFTs).
MATERIAL AND METHODS
Thirty adults with asthma with persistent-mild, persistent-moderate, and persistent-severe categories as per standard clinical guidelines were evaluated with inspiratory and expiratory HRCT for various imaging features of bronchial asthma. Expiratory HRCT scan were used to quantify degree of air-trapping, and their values quantified as "pixel index," using a special "density' mask" software. Complete spirometry and body plethysmography were performed on each patient within 0-2 days of HRCT scans. HRCT findings were correlated with the clinical severity groups and the CT pixel indices (PI) were correlated with the PFT results using correlation coefficients and linear regression analysis.
RESULTS
The inspiratory CT findings did not correlate with increase in disease severity. Expiratory scans accurately quantified areas of air trapping. CT-PI correlated well with PFT values indicative of airway obstruction and airflow limitation, which helped differentiate patients with asthma with increasing severity from those with milder forms of the disease.
CONCLUSION
Expiratory thin-section CT is a useful objective method to quantify air-trapping in people with asthma. The air-trapping score measured in "pixel indices" correlates well with PFT results and can successfully identify patients with severe asthma. Further studies are needed to confirm if this parameter can serve as a potential marker for airway remodeling and declining lung function.
Topics: Adult; Humans; Asthma; Lung; Respiratory Function Tests; Tomography, X-Ray Computed; Tomography
PubMed: 36317289
DOI: 10.1177/02841851221135233 -
Environmental Pollution (Barking, Essex... Oct 2023Air pollution has been associated with the development of atherosclerosis; however, the pathophysiological mechanisms underlying pro-atherosclerotic effects of air...
Pro-inflammation and pro-atherosclerotic responses to short-term air pollution exposure associated with alterations in sphingolipid ceramides and neutrophil extracellular traps.
Air pollution has been associated with the development of atherosclerosis; however, the pathophysiological mechanisms underlying pro-atherosclerotic effects of air pollution exposure remain unclear. We conducted a prospective panel study in Beijing and recruited 152 participants with four monthly visits from September 2019 to January 2020. Linear mixed-effect models were applied to estimate the associations linking short-term air pollution exposure to biomarkers relevant to ceramide metabolism, pro-inflammation (neutrophil extracellular traps formation and systemic inflammation) and pro-atherosclerotic responses (endothelial stimulation, plaque instability, coagulation activation, and elevated blood pressure). We further explored whether ceramides and inflammatory indicators could mediate the alterations in the profiles of pro-atherosclerotic responses. We found that significant increases in levels of circulating ceramides of 9.7% (95% CIs: 0.7, 19.5) to 96.9% (95% CIs: 23.1, 214.9) were associated with interquartile range increases in moving averages of ambient air pollutant metrics, including fine particulate matter (PM), black carbon, particles in size fractions of 100-560 nm, nitrogen dioxide, carbon monoxide and sulfur dioxide at prior up to 7 days. Higher air pollution levels were also associated with activated neutrophils (increases in citrullinated histone H3, neutrophil elastase, double-stranded DNA, and myeloperoxidase) and exacerbation of pro-atherosclerotic responses (e.g., increases in vascular endothelial growth factor, lipoprotein-associated phospholipase A2, matrix metalloproteinase-8, P-selectin, and blood pressure). Mediation analyses further showed that dysregulated ceramide metabolism and potentiated inflammation could mediate PM-associated pro-atherosclerotic responses. Our findings extend the understanding on potential mechanisms of air pollution-associated atherosclerosis, and suggest the significance of reducing air pollution as priority in urban environments.
Topics: Humans; Ceramides; Sphingolipids; Extracellular Traps; Prospective Studies; Vascular Endothelial Growth Factor A; Air Pollution; Air Pollutants; Inflammation; Particulate Matter; Atherosclerosis; Environmental Exposure
PubMed: 37541379
DOI: 10.1016/j.envpol.2023.122301 -
Chemical Engineering Journal (Lausanne,... Dec 2021Infectious pollutants bioaerosols can threaten human public health. In particular, the indoor environment provides a unique exposure situation to induce infection...
Infectious pollutants bioaerosols can threaten human public health. In particular, the indoor environment provides a unique exposure situation to induce infection through airborne transmission like SARS-CoV-2. To prevent the infection from spreading, personal protective equipment or indoor air purification is necessary. However, it has been discovered that the conventional filter can become contaminated by pathogen-containing aerosols, meaning that advanced filtering and self-sterilization systems are required. Here, we fabricate a multilayered nanocoating around the fabric using laponite (LAP) with Cu ions (LAP-Cu nanocoating) two contradictory functions in one system: trapping proteinaceous pathogens and antibacterial effect. Due to the strong LAP-protein interaction, albumin and spike protein (S-protein) are trapped into the fabric when proteins are sprayed using a nebulizer. The protein-blocking performance of the nanocoated fabric is 9.55-fold higher than bare fabric. These trapping capacities are retained after rinsing and repeated adsorption cycles, showing reproducibility for air filtration. Even though the protein-binding occurred, the LAP-Cu fabric indicates antibacterial effect. LAP-Cu fabric has an equivalent air and water transmittance rate to that of bare fabric with a stability under physiological environment. Therefore, given its excellent "Spear-and-shield" functions, the proposed LAP-Cu fabric shows great potential for use in filter and masks during the viral pandemic.
PubMed: 34131388
DOI: 10.1016/j.cej.2021.130763 -
Radiology Apr 2020Background CT is used to quantify abnormal changes in the lung parenchyma of smokers that might overlap chronic obstructive pulmonary disease (COPD), but studies on the... (Observational Study)
Observational Study
Background CT is used to quantify abnormal changes in the lung parenchyma of smokers that might overlap chronic obstructive pulmonary disease (COPD), but studies on the progression of expiratory air trapping in smokers are scarce. Purpose To evaluate the relationship between longitudinal changes in forced expiratory volume in 1 second (FEV) and CT-quantified emphysema and air trapping in smokers. Materials and Methods Cigarette smokers with and those without COPD participating in the multicenter observational COPDGene study were evaluated. Subjects underwent inspiratory and expiratory chest CT and spirometry at baseline and 5-year follow-up. Emphysema was quantified by using adjusted lung density (ALD). Air trapping was quantified by using mean lung density at expiratory CT and CT-measured functional residual capacity-to-total lung volume ratio. Linear models were used to regress quantitative CT measurements taken 5 years apart, and models were fit with and without adding FEV as a predictor. Analyses were stratified by Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage (GOLD 0, no COPD; GOLD 1, mild COPD; GOLD 2, moderate COPD; GOLD 3, severe COPD; GOLD 4, very severe COPD). Subjects with preserved FEV-to-forced vital capacity ratio and reduced FEV percentage predicted were categorized as having preserved ratio impaired spirometry (PRISm). Results A total of 4211 subjects (503 with PRISm; 2034 with GOLD 0, 388 with GOLD 1, 816 with GOLD 2, 381 with GOLD 3, 89 with GOLD 4) were evaluated. ALD decreased by 1.7 g/L (95% confidence interval [CI]: -2.5, -0.9) in subjects with GOLD 0 at baseline and by 5.3 g/L (95% CI: -6.2, -4.4) in those with GOLD 1-4 ( < .001 for both). When adjusted for changes in FEV, corresponding numbers were -2.2 (95% CI: -3.0, -1.3) and -4.6 g/L (95% CI: -5.6, -3.4) ( < .001 for both). Progression in air trapping was identified only in GOLD stage 2-4. Approximately 33%-50% of changes in air trapping in GOLD stages 2-4 were accounted for by changes in FEV. Conclusion CT measures of emphysema and air trapping increased over 5 years in smokers. Forced expiratory volume in one second accounted for less than 10% of emphysema progression and less than 50% of air trapping progression detected at CT. © RSNA, 2020
Topics: Aged; Air; Disease Progression; Female; Forced Expiratory Volume; Humans; Male; Middle Aged; Prospective Studies; Pulmonary Disease, Chronic Obstructive; Pulmonary Emphysema; Severity of Illness Index; Smoking; Time Factors; Tomography, X-Ray Computed
PubMed: 32013794
DOI: 10.1148/radiol.2020191429