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Search Results (9,267)

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Keywords = air quality

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18 pages, 4581 KiB  
Article
Seasonal Characterization of the Aerobiome in Hematopoietic Stem Cell Transplant Rooms: Potential Risk for Immunosuppressed Patients
by Emilio Mariano Durán-Manuel, Edgar Fiscal-Baxin, Andres Emmanuel Nolasco-Rojas, Miguel Ángel Loyola-Cruz, Clemente Cruz-Cruz, Marianela Paredes-Mendoza, Adolfo López-Ornelas, Dulce Milagros Razo Blanco-Hernández, Nayeli Goreti Nieto-Velázquez, Aída Verónica Rodríguez-Tovar, Adrián Ramírez-Granillo, Enzo Vásquez-Jiménez, Verónica Fernández-Sánchez, Erika Gómez-Zamora, Mónica Alethia Cureño-Díaz, Andrea Milán-Salvatierra, Carlos Alberto Jiménez-Zamarripa, Claudia Camelia Calzada-Mendoza and Juan Manuel Bello-López
Microorganisms 2024, 12(11), 2352; https://doi.org/10.3390/microorganisms12112352 - 18 Nov 2024
Abstract
Infections pose a risk for patients undergoing hematopoietic stem cell (HSC) transplants due to their immunosuppression, making them susceptible to opportunistic infections. Therefore, understanding the composition of the aerobiome in this area is vital. The aim of this study was to characterize the [...] Read more.
Infections pose a risk for patients undergoing hematopoietic stem cell (HSC) transplants due to their immunosuppression, making them susceptible to opportunistic infections. Therefore, understanding the composition of the aerobiome in this area is vital. The aim of this study was to characterize the aerobiome in an HSC transplant area, evaluating the impact of infrastructure and health personnel operations on air contamination. The environmental parameters and aerobiome of the HSC transplant area at Hospital Juárez de México were quantified over one year. Finally, a double-entry Vester matrix was constructed to classify problems according to their degree of causality. The abundance and taxonomic diversity of the aerobiome were dependent on seasonality, environmental factors, and high-efficiency filtration. Gram-positive bacteria predominated, followed by fungi and Gram-negative bacteria. ANOVA revealed significant differences in the bacterial aerobiome but not in the fungal aerobiome among the transplant rooms. Clinically, fungi such as Aspergillus fumigatus, Alternaria spp., Cladosporium spp., and Penicillium spp. were identified. ESKAPE bacteria typing revealed clonal dispersion. Finally, the Vester matrix highlighted critical problems associated with contamination due to the absence of HEPA filtration and non-adherence in patient management practices. HEPA filtration and positive pressure are essential to improve the air quality and reduce the microbiological load. However, the control areas will depend on patient management and routine activities, such as entry protocols in controlled areas. Full article
(This article belongs to the Section Public Health Microbiology)
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22 pages, 942 KiB  
Article
Microbial Indoor Air Quality Within Greenhouses and Polytunnels Is Crucial for Sustainable Horticulture (Malopolska Province, Poland Conditions)
by Jacek Kozdrój, Dariusz Roman Ropek, Krzysztof Frączek, Karol Bulski and Barbara Breza-Boruta
Sustainability 2024, 16(22), 10058; https://doi.org/10.3390/su162210058 - 18 Nov 2024
Abstract
Sustainable horticulture is crucially based on the greenhouse production of vegetables under controlled conditions. In this study, we wanted to learn how cultivated plants may impact indoor air quality and whether the workers can be exposed to bioaerosols in a similar way in [...] Read more.
Sustainable horticulture is crucially based on the greenhouse production of vegetables under controlled conditions. In this study, we wanted to learn how cultivated plants may impact indoor air quality and whether the workers can be exposed to bioaerosols in a similar way in these settings. The study objective was to test the hypothesis that the microbial concentrations, distribution of bioaerosol particle sizes, and composition of the airborne microbiome are specific to greenhouses, polytunnels, and open-air sites. The air samples were collected to assess the concentration of total culturable bacteria (TCB), fungi, actinomycetes, and β-haemolytic bacteria and for the identification of bacterial and fungal strains. Higher concentrations of TCB and fungi were found in the greenhouse (log 3.71 and 3.49 cfu m−3, respectively) than in polytunnels (log 2.60–2.48 and 2.51–2.31 cfu m−3, respectively) during the vegetation of cucumbers. These airborne microbes were represented by a significant contribution of the respirable fraction with a distinct contribution of fine particles in size below 4.7 µm. Cultivation of cucumbers resulted in the higher emission of airborne microorganisms in contrast with growing herbs such as oregano and basil. In total, 35 different bacteria and 12 fungal species, including pathogenic or allergenic agents, were identified within the studied sites. The workers can be exposed to increased concentrations of TCB and fungi in the greenhouse during the plant vegetation. It might be recommended to properly manage greenhouses and polytunnels, dispose of dust sources, and maintain appropriate ventilation to sustain relevant air quality. Full article
(This article belongs to the Special Issue Soil, Plant and Human Health in Sustainable Environment)
22 pages, 4010 KiB  
Article
Dynamic Changes of Air Particle Pollutants and Scale Regulation of Forest Landscape in a Typical High-Latitude City
by Chang Zhai, Ning Fang, Xuan Xu, Bingyan Liu, Guangdao Bao, Zhibin Ren and Ruoxuan Geng
Land 2024, 13(11), 1947; https://doi.org/10.3390/land13111947 - 18 Nov 2024
Abstract
Particulate pollutants, particularly PM2.5 and PM10, pose serious threats to human health and environmental quality. Therefore, effectively mitigating and reducing the concentrations of these pollutants is crucial for human survival and development. In this study, we analyzed the [...] Read more.
Particulate pollutants, particularly PM2.5 and PM10, pose serious threats to human health and environmental quality. Therefore, effectively mitigating and reducing the concentrations of these pollutants is crucial for human survival and development. In this study, we analyzed the distribution characteristics of air particulate pollutants in a typical high-latitude city, extracted urban forest areas from high-resolution remote sensing images, and examined the changing characteristics of PM concentration and the relationship between landscape pattern indexes and PM at different scales. The results showed that the concentrations of PM2.5 and PM10 were highest in winter and lowest in summer. At the small scales of 0.5 km × 0.5 km to 1.5 km × 1.5 km, PM concentration decreased with the decrease in PARA (Perimeter–Area Ratio). At the mesoscales of 2 km × 2 km to 2.5 km × 2.5 km, both PARA and CIRCLE (Related Circumscribing Circle) were highly significant (p < 0.001) correlated with PM concentration. At the large scales of 3 km × 3 km to 4 km × 4 km, PARA and PAFRAC (Perimeter–Area Fractal Dimension) were positively correlated with PM concentration. Our study indicates that reducing the complexity of forest patches in small-scale planning can help mitigate particulate air pollution. In the medium scale of urban forest planning, the more regular the forest patch shape and the more similar the patch shape to the strip, the better PM can be alleviated, while in large-scale planning, increasing the forest area and making the patches more normalized and simplified can reduce PM concentration. Moreover, reducing the complexity of forest patches can significantly mitigate PM pollution at all scales. The results of this research provide theoretical support and guidance for improving air quality in urban forest planning at different scales. Full article
17 pages, 2260 KiB  
Article
Condensable Particulate Matter Removal and Its Mechanism by Phase Change Technology During Wet Desulfurization Process
by Hui Tong, Yun Xu, Qiangqiang Ren, Hao Wu, Linzhi Shen, Menglong Sun and Hongmin Yang
Separations 2024, 11(11), 330; https://doi.org/10.3390/separations11110330 - 18 Nov 2024
Abstract
Limestone-gypsum wet flue gas desulfurization (WFGD) played a key role in SOx removal and clean emissions. However, it would also affect the condensable particulate matter (CPM) removal and compositions. The effects of the WFGD system on the removal of CPM and the contents [...] Read more.
Limestone-gypsum wet flue gas desulfurization (WFGD) played a key role in SOx removal and clean emissions. However, it would also affect the condensable particulate matter (CPM) removal and compositions. The effects of the WFGD system on the removal of CPM and the contents of soluble ions in CPM were investigated in a spray desulfurization tower at varied conditions. The results indicate that the emission concentration of CPM decreased from 7.5 mg/Nm3 to 3.7 mg/Nm3 following the introduction of cold water spray and hot alkali droplet spray systems. This resulted in a CPM reduction rate of approximately 51%, reducing the percentage of CPM in total particulate matter and solving the problem of substandard particulate matter emission concentrations in some coal-fired power plants. The concentrations of NO3, SO42−, and Cl among the soluble ions decreased by 41–66.6%. As the liquid−to−gas ratio of the cold water spray and hot alkali droplet spray increased, CPM came into contact with more spray, which accelerated dissolution and chemical reactions. Consequently, the CPM emission concentration decreased by 17.4–19%. The liquid−to−gas ratio has a great effect on the ion concentrations of NO3, SO42−, Cl and NH4+, with a decrease of 28–66%. The temperatures of the cold water spray and the hot alkali droplet spray primarily affect the ionic concentrations of SO42− and Ca2+, leading to a decrease of 32.3–51%. When the SO2 concentration increased from 0 mg/Nm3 to 1500 mg/Nm3, large amounts of SO2 reacted with the desulfurization slurry to form new CPM and its precursors, the CPM emission concentration increased by 57–68.4%. This study addresses the issue of high Concentration of CPM emissions from coal-fired power plants in a straightforward and efficient manner, which is significant for enhancing the air quality and reducing hazy weather conditions. Also, it provides a theoretical basis and technical foundation for the efficient removal of CPM from actual coal-fired flue gas. Full article
14 pages, 1157 KiB  
Article
Concrete Actions for Improving Indoor Air Quality in Korea: Advancing Public Health for Vulnerable Populations
by Seongho Jeon, Hyosun Lee, Kyunghee Jo, Yongsung Park, Wonsuck Yoon and Jaewook Choi
Atmosphere 2024, 15(11), 1389; https://doi.org/10.3390/atmos15111389 - 18 Nov 2024
Abstract
In modern society, individuals spend an increasing amount of time indoors, emphasizing the importance of understanding the health impacts of indoor environments. This study focused on measuring indoor air quality to identify vulnerable populations and observe the effects of residential environment improvements on [...] Read more.
In modern society, individuals spend an increasing amount of time indoors, emphasizing the importance of understanding the health impacts of indoor environments. This study focused on measuring indoor air quality to identify vulnerable populations and observe the effects of residential environment improvements on air quality. Targeting low-income families and elderly households, known for their heightened vulnerability to environmental health risks, the study involved direct visits to 2328 low-income households across 16 cities and provinces in South Korea from 2021 to 2022. Indoor air quality parameters, including PM2.5, PM10, total volatile organic compounds (TVOC), formaldehyde (HCHO), and airborne mold, were measured. Among these households, 300 with critically compromised living conditions received support for wallpaper and paneling replacement. Comparative measurements before and after the renovations revealed that single-person households had higher levels of PM2.5 and TVOC compared with households with four or more members. Additionally, households with elevated concentrations of airborne mold also exhibited higher levels of PM2.5 and PM10. Importantly, households that received environmental improvements showed a significant reduction in airborne mold concentration by approximately 50% or more. This study underscores the importance of indoor environmental health and provides valuable evidence supporting policies focused on health promotion and residential welfare improvements for vulnerable populations. The research is distinguished by its comprehensive nature, involving direct measurements from nearly 2000 households nationwide, rather than relying solely on secondary data. Full article
(This article belongs to the Topic Impacts of Air Quality on Environment and Human Health)
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28 pages, 12256 KiB  
Article
Design and Testing of a Small-Scale Composting Facility for Sheep Manure Utilizing Aeration and Thermal Treatment
by Jian Wang, Kailin Ren and Longfei Zhang
Agriculture 2024, 14(11), 2070; https://doi.org/10.3390/agriculture14112070 - 18 Nov 2024
Viewed by 168
Abstract
Inner Mongolia has the largest sheep population among China’s provinces, resulting in the production of a substantial amount of sheep manure. If left untreated, this manure can contribute to environmental pollution. However, sheep manure serves a dual purpose: it can be both a [...] Read more.
Inner Mongolia has the largest sheep population among China’s provinces, resulting in the production of a substantial amount of sheep manure. If left untreated, this manure can contribute to environmental pollution. However, sheep manure serves a dual purpose: it can be both a pollutant and a valuable source of organic fertilizer. Consequently, there is an urgent need to address the environmental issues arising from manure accumulation and its unused status. In this paper, a viable solution is proposed: the conversion of manure into fertilizer through a composting unit incorporating high-temperature aerobic fermentation technology. This unit, tailored for small farms and individual farmers, integrates critical functions such as ventilation, heating, and turning. Additionally, it boasts excellent thermal insulation, enhancing composting efficiency and enabling precise control over fermentation conditions. This design mitigates heat loss and accelerates maturation, addressing common challenges in traditional composting. The design process encompassed both equipment construction and control systems, with a primary focus on compost fermentation and aeration heating. The components were carefully designed or selected based on theoretical analysis and subsequently validated using simulation software, including EDEM and Fluent. The control system seamlessly integrates a touch screen interface, PLC programming, and control circuits to manage air pumps and electric heaters in response to changes in temperature and oxygen concentration. Furthermore, it controls the motors during the recovery phase. A comprehensive performance evaluation was conducted, revealing notable improvements. Under artificially heated conditions, the maximum temperature of the compost increased by approximately 20 °C, the composting cycle was reduced by roughly 4 days, and the seed germination index (GI) rose by about 9% when compared to natural fermentation. Thus, this device significantly accelerates composting and improves fertilizer quality by increasing the decomposition rate. Full article
(This article belongs to the Section Agricultural Technology)
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18 pages, 7751 KiB  
Article
GIS-Based Spatial Analysis and Strategic Placement of Fine Dust Alert Systems for Vulnerable Populations in Gangseo District
by Jaewook Lee, Junyoung Jang, Jaeuk Im and Jae Hong Lee
Appl. Sci. 2024, 14(22), 10610; https://doi.org/10.3390/app142210610 - 18 Nov 2024
Viewed by 283
Abstract
Air pollution, particularly fine particulate matter (PM), poses significant health risks to vulnerable populations such as children, older adults, and individuals with chronic illnesses. Understanding the spatial distribution of these populations and their access to air quality information is crucial for effective interventions. [...] Read more.
Air pollution, particularly fine particulate matter (PM), poses significant health risks to vulnerable populations such as children, older adults, and individuals with chronic illnesses. Understanding the spatial distribution of these populations and their access to air quality information is crucial for effective interventions. In urban areas like Gangseo District, the distribution of essential facilities and accessibility varies greatly. While studies have highlighted the health impacts of PM, research on optimizing air quality monitoring for at-risk groups remains limited. This study aims to identify optimal locations for air quality monitoring by analyzing the spatial distribution of vulnerable populations and facility accessibility. Using Geographic Information Systems (GIS) and isochrone maps, we identified areas with high concentrations of vulnerable groups and poor access to healthcare facilities. Our findings revealed significant disparities in access to air quality information, with some high-risk areas underserved by current monitoring systems. This study integrated demographic data and spatial analysis to propose strategic monitoring placements. The methodology can be applied to other urban settings and offers a framework for improving air quality management. This study underscores the importance of targeted air quality monitoring to protect vulnerable populations and suggests practical steps for policymakers to enhance public health. Full article
(This article belongs to the Special Issue Air Pollution and Its Impact on the Atmospheric Environment)
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21 pages, 1998 KiB  
Article
Sustainable Commuting: Active Transport Practices and Slovenian Data Analysis
by Aleksandar Šobot, Sergej Gričar and Štefan Bojnec
Urban Sci. 2024, 8(4), 214; https://doi.org/10.3390/urbansci8040214 - 18 Nov 2024
Viewed by 277
Abstract
This study examines the influence of transportation policies and urbanisation on cycling participation and environmental sustainability in Slovenia. Factor and regression analyses were employed. The yearly data from 2008 to 2021 were isolated. A modest increase in urban cycling frequency was observed, bolstered [...] Read more.
This study examines the influence of transportation policies and urbanisation on cycling participation and environmental sustainability in Slovenia. Factor and regression analyses were employed. The yearly data from 2008 to 2021 were isolated. A modest increase in urban cycling frequency was observed, bolstered by investments in environmental protection and safety enhancements; however, additional evidence is needed to confirm the long-term effects (H1). Furthermore, while increased cycling was linked to a reduction in CO2 emissions and improved air quality, the overall environmental benefits were found to be affected by other factors, such as motorisation and public transportation in summer (H2). The study revealed that the introduction of reduced urban speed limits and expanded cycling lanes significantly enhanced cycling safety and desirability, leading to a shift from car usage to bicycles (RQ). These findings indicate that cycling could play a vital role in advancing Slovenia’s sustainable development goals, emphasising the need for continued investments and supportive urbanisation policies. Full article
(This article belongs to the Special Issue Sustainable Transportation and Urban Environments-Public Health)
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16 pages, 3690 KiB  
Article
CHIMBO Air Quality Modeling System: Verification and Processes Analysis
by Tony Christian Landi, Marco Paglione, Mauro Morichetti, Fabio Massimo Grasso, Fabrizio Roccato, Rita Cesari and Oxana Drofa
Atmosphere 2024, 15(11), 1386; https://doi.org/10.3390/atmos15111386 - 17 Nov 2024
Viewed by 361
Abstract
This study presents an evaluation of the CHIMBO modeling chain applied to the Italian domain, specifically focusing on the Po Valley subdomain over the one-year period of 2019. The comparison between simulated and observed data indicates that the performance of the CHIMBO model [...] Read more.
This study presents an evaluation of the CHIMBO modeling chain applied to the Italian domain, specifically focusing on the Po Valley subdomain over the one-year period of 2019. The comparison between simulated and observed data indicates that the performance of the CHIMBO model aligns well with existing literature on other state-of-the-art models. The results demonstrate that the CHIMBO chain is particularly effective for regional-scale quantitative assessments of pollutant distribution, comparable to that of CAMS ensemble models. The analysis of key chemical species in particulate matter reveals that the CHIMBO model accurately represents the average concentrations of organic and elemental carbon, as well as secondary inorganic compounds (sulfate, nitrate, and ammonium), particularly at background monitoring stations in the flat terrain of the Po Valley, with the exception of Aosta, a city located at about 500 m asl. However, seasonal discrepancies were identified, especially during winter months, when significant underestimations were observed for several species, including elemental and organic carbon, predominantly at background sites. These underestimations are likely attributed to various factors: (i) inadequate estimations of primary emissions, particularly from domestic heating; (ii) the limited effectiveness of secondary formation processes under winter conditions characterized by low photochemical activity and high humidity; and (iii) excessive dilution of pollutants during calm wind conditions due to overestimation of wind intensity. In conclusion, while the CHIMBO modeling chain serves as a robust tool for mesoscale atmospheric composition investigations, limitations persist related to emissions inventories and meteorological parameters, which remain critical drivers of atmospheric processes. Full article
(This article belongs to the Section Air Quality)
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16 pages, 1319 KiB  
Article
The Impact of Carbon-Emission Trading Scheme Policies on Air Quality in Chinese Cities
by Youtian Fan, Zhiying Chen and Taiyi He
Sustainability 2024, 16(22), 10023; https://doi.org/10.3390/su162210023 - 17 Nov 2024
Viewed by 314
Abstract
Air quality issues have a significant impact on human health and are an important issue affecting sustainable development. With the implementation of China’s carbon-emission trading scheme, carbon emissions have been effectively reduced, which has a potential impact on air quality. This article uses [...] Read more.
Air quality issues have a significant impact on human health and are an important issue affecting sustainable development. With the implementation of China’s carbon-emission trading scheme, carbon emissions have been effectively reduced, which has a potential impact on air quality. This article uses a time-point difference-in-differences model to analyze the impact of the implementation of a carbon-emission trading scheme on the air quality in 284 cities in China from 2008 to 2021. During the inspection, the impact of policies on overall air quality and on various types of air pollutants was discussed separately. The research results show that the implementation of the carbon-emission trading scheme helps improve urban air quality issues, reduce the concentration of air pollutants such as PM2.5 and SO2, and improve the urban environment; with controlled variables, it has reduced PM2.5 by 2.548 units, SO2 by 0.180 units, NOx by 0.295 units, and has promoted the sustainable development of cities. In addition, the policy mainly has a positive impact on air quality by promoting green technology innovation and industrial upgrading, further demonstrating the spillover effect of the policy. There is also some regional heterogeneity in the policies, especially in the central and western regions, where the reduction effect of SO2 and nitrogen oxides is not significant. Full article
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12 pages, 3108 KiB  
Article
A Microfluidic-Based Sensing Platform for Rapid Quality Control on Target Cells from Bioreactors
by Alessia Foscarini, Fabio Romano, Valeria Garzarelli, Antonio Turco, Alessandro Paolo Bramanti, Iolena Tarantini, Francesco Ferrara, Paolo Visconti, Giuseppe Gigli and Maria Serena Chiriacò
Sensors 2024, 24(22), 7329; https://doi.org/10.3390/s24227329 (registering DOI) - 16 Nov 2024
Viewed by 334
Abstract
We investigated the design and characterization of a Lab-On-a-Chip (LoC) cell detection system primarily designed to support immunotherapy in cancer treatment. Immunotherapy uses Chimeric Antigen Receptors (CARs) and T Cell Receptors (TCRs) to fight cancer, engineering the response of the immune system. In [...] Read more.
We investigated the design and characterization of a Lab-On-a-Chip (LoC) cell detection system primarily designed to support immunotherapy in cancer treatment. Immunotherapy uses Chimeric Antigen Receptors (CARs) and T Cell Receptors (TCRs) to fight cancer, engineering the response of the immune system. In recent years, it has emerged as a promising strategy for personalized cancer treatment. However, it requires bioreactor-based cell culture expansion and manual quality control (QC) of the modified cells, which is time-consuming, labour-intensive, and prone to errors. The miniaturized LoC device for automated QC demonstrated here is simple, has a low cost, and is reliable. Its final target is to become one of the building blocks of an LoC for immunotherapy, which would take the place of present labs and manual procedures to the benefit of throughput and affordability. The core of the system is a commercial, on-chip-integrated capacitive sensor managed by a microcontroller capable of sensing cells as accurately measured charge variations. The hardware is based on standardized components, which makes it suitable for mass manufacturing. Moreover, unlike in other cell detection solutions, no external AC source is required. The device has been characterized with a cell line model selectively labelled with gold nanoparticles to simulate its future use in bioreactors in which labelling can apply to successfully engineered CAR-T-cells. Experiments were run both in the air—free drop with no microfluidics—and in the channel, where the fluid volume was considerably lower than in the drop. The device showed good sensitivity even with a low number of cells—around 120, compared with the 107 to 108 needed per kilogram of body weight—which is desirable for a good outcome of the expansion process. Since cell detection is needed in several contexts other than immunotherapy, the usefulness of this LoC goes potentially beyond the scope considered here. Full article
(This article belongs to the Section Biosensors)
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17 pages, 3997 KiB  
Article
The Influence of Relative Humidity and Pollution on the Meteorological Optical Range During Rainy and Dry Months in Mexico City
by Blanca Adilen Miranda-Claudes and Guillermo Montero-Martínez
Atmosphere 2024, 15(11), 1382; https://doi.org/10.3390/atmos15111382 - 16 Nov 2024
Viewed by 226
Abstract
The Meteorological Optical Range (MOR) is a measurement of atmospheric visibility. Visibility impairment has been linked to increased aerosol levels in the air. This study conducted statistical analyses using meteorological, air pollutant concentration, and MOR data collected in Mexico City from [...] Read more.
The Meteorological Optical Range (MOR) is a measurement of atmospheric visibility. Visibility impairment has been linked to increased aerosol levels in the air. This study conducted statistical analyses using meteorological, air pollutant concentration, and MOR data collected in Mexico City from August 2014 to December 2015 to determine the factors contributing to haze occurrence (periods when MOR < 10,000 m), defined using a light scatter sensor (PWS100). The outcomes revealed seasonal patterns in PM2.5 and relative humidity (RH) for haze occurrence along the year. PM2.5 levels during hazy periods in the dry season were higher compared to the wet season, aligning with periods of poor air quality (PM2.5 > 45 μg/m3). Pollutant-to-CO ratios suggested that secondary aerosols’ production, led by SO2 conversion to sulfate particles, mainly impacts haze occurrence during the dry season. Meanwhile, during the rainy season, the PWS100 registered haze events even with PM2.5 values close to 15 μg/m3 (considered good air quality). The broadened distribution of extinction efficiency during the wet period and its correlation with RH suggest that aerosol water vapor uptake significantly impacts visibility during this season. Therefore, attributing poor visibility strictly to poor air quality may not be appropriate for all times and locations. Full article
(This article belongs to the Section Meteorology)
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35 pages, 8115 KiB  
Article
Fashion Wears Sustainable Leather: A Social and Strategic Analysis Toward Sustainable Production and Consumption Goals
by Idiano D’Adamo, Marta Gagliarducci, Martina Iannilli and Valeria Mangani
Sustainability 2024, 16(22), 9971; https://doi.org/10.3390/su16229971 - 15 Nov 2024
Viewed by 499
Abstract
While fashion and sustainability are often proposed as opposing concepts, many companies in the fashion industry are actively working to transform their operations to achieve greater sustainability. The production of leather goods significantly contributes to air and water pollution and generates challenging waste [...] Read more.
While fashion and sustainability are often proposed as opposing concepts, many companies in the fashion industry are actively working to transform their operations to achieve greater sustainability. The production of leather goods significantly contributes to air and water pollution and generates challenging waste disposal issues. The present study explored emerging sustainable paradigms in the leather goods industry through both social and strategic analyses. The results indicate that, although consumers are often unaware of the differences among leather types, there is a growing openness to sustainable alternatives and a willingness to pay for these products. Quality and durability are key consumer priorities, though a bias toward fast fashion persists. Notably, while consumers value vegan leather as a sustainable alternative, experts caution that synthetic leather alternatives may have greater environmental drawbacks compared to traditional leather. The work supports SDG 12 by advocating for reduced reliance on materials with a high environmental impact and the adoption of sustainable alternatives. Enhanced consumer communication may also drive the industry toward a model that integrates environmental and social responsibility with profitability. Given the prestigious status of leather goods within the Made in Italy initiative, the present work suggests that the value of vegan leather may increase within the global market. Full article
(This article belongs to the Section Development Goals towards Sustainability)
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22 pages, 5816 KiB  
Article
Causality-Driven Feature Selection for Calibrating Low-Cost Airborne Particulate Sensors Using Machine Learning
by Vinu Sooriyaarachchi, David J. Lary, Lakitha O. H. Wijeratne and John Waczak
Sensors 2024, 24(22), 7304; https://doi.org/10.3390/s24227304 - 15 Nov 2024
Viewed by 325
Abstract
With escalating global environmental challenges and worsening air quality, there is an urgent need for enhanced environmental monitoring capabilities. Low-cost sensor networks are emerging as a vital solution, enabling widespread and affordable deployment at fine spatial resolutions. In this context, machine learning for [...] Read more.
With escalating global environmental challenges and worsening air quality, there is an urgent need for enhanced environmental monitoring capabilities. Low-cost sensor networks are emerging as a vital solution, enabling widespread and affordable deployment at fine spatial resolutions. In this context, machine learning for the calibration of low-cost sensors is particularly valuable. However, traditional machine learning models often lack interpretability and generalizability when applied to complex, dynamic environmental data. To address this, we propose a causal feature selection approach based on convergent cross mapping within the machine learning pipeline to build more robustly calibrated sensor networks. This approach is applied in the calibration of a low-cost optical particle counter OPC-N3, effectively reproducing the measurements of PM1 and PM2.5 as recorded by research-grade spectrometers. We evaluated the predictive performance and generalizability of these causally optimized models, observing improvements in both while reducing the number of input features, thus adhering to the Occam’s razor principle. For the PM1 calibration model, the proposed feature selection reduced the mean squared error on the test set by 43.2% compared to the model with all input features, while the SHAP value-based selection only achieved a reduction of 29.6%. Similarly, for the PM2.5 model, the proposed feature selection led to a 33.2% reduction in the mean squared error, outperforming the 30.2% reduction achieved by the SHAP value-based selection. By integrating sensors with advanced machine learning techniques, this approach advances urban air quality monitoring, fostering a deeper scientific understanding of microenvironments. Beyond the current test cases, this feature selection method holds potential for broader applications in other environmental monitoring applications, contributing to the development of interpretable and robust environmental models. Full article
(This article belongs to the Section Sensor Networks)
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22 pages, 5925 KiB  
Article
Research on Energy Dissipation Mechanism of Cobweb-like Disk Resonator Gyroscope
by Huang Yi, Bo Fan, Feng Bu, Fang Chen and Xiao-Qing Luo
Micromachines 2024, 15(11), 1380; https://doi.org/10.3390/mi15111380 - 15 Nov 2024
Viewed by 292
Abstract
The micro disk resonator gyroscope is a micro-mechanical device with potential for navigation-grade applications, where the performance is significantly influenced by the quality factor, which is determined by various energy dissipation mechanisms within the micro resonant structure. To enhance the quality factor, these [...] Read more.
The micro disk resonator gyroscope is a micro-mechanical device with potential for navigation-grade applications, where the performance is significantly influenced by the quality factor, which is determined by various energy dissipation mechanisms within the micro resonant structure. To enhance the quality factor, these gyroscopes are typically enclosed in high-vacuum packaging. This paper investigates a wafer-level high-vacuum-packaged (<0.1 Pa) cobweb-like disk resonator gyroscope, presenting a systematic and comprehensive theoretical analysis of the energy dissipation mechanisms, including air damping, thermoelastic damping, anchor loss, and other factors. Air damping is analyzed using both a continuous fluid model and an energy transfer model. The analysis results are validated through quality factor testing on batch samples and temperature characteristic testing on individual samples. The theoretical results obtained using the energy transfer model closely match the experimental measurements, with a maximum error in the temperature coefficient of less than 2%. The findings indicate that air damping and thermoelastic damping are the predominant energy dissipation mechanisms in the cobweb-like disk resonant gyroscope under high-vacuum conditions. Consequently, optimizing the resonator to minimize thermoelastic and air damping is crucial for designing high-performance gyroscopes. Full article
(This article belongs to the Special Issue Advances in MEMS Inertial Sensors)
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