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1.
British Food Journal ; 125(7):2350-2367, 2023.
Article in English | ProQuest Central | ID: covidwho-20244754

ABSTRACT

PurposeThe purpose of this paper was to determine the profile of dairy product consumers in the organic market.Design/methodology/approachThe study was based on a survey questionnaire developed by the author and administered to a total of 1,108 respondents. The statistical analysis (including descriptive statistics, the analysis of the discriminative function and the Chi2 test was performed with the use of Statistica 13.1 PL. The respondents' gender was the factor behind the differences in how they behaved.FindingsThe consumers indicated the channels they rely upon to find information on organic dairy products;in addition to trusting the opinions of their family members and experts, they also use web platforms. Further, they specified their preferred locations for buying favorite products during the pandemic: specialized organic food shops, large distribution chains and online stores.Practical implicationsThese outcomes will help in identifying target consumer segments and information channels for specific information and advertising messages. They also form an important resource for developing some potential strategies which the supply chain stakeholders could implement to promote organic consumption of dairy products.Originality/valueThis study identifies consumers' preferred dairy products;motives for purchasing organic dairy products;barriers that consumers believe exist in the market;sources of knowledge about products purchased by consumers;and consumers' preferred channels for purchasing organic dairy products. To the best of the author's knowledge, this is the first study of dairy product consumers in the organic market in Poland.

2.
Understanding individual experiences of COVID-19 to inform policy and practice in higher education: Helping students, staff, and faculty to thrive in times of crisis ; : 87-98, 2022.
Article in English | APA PsycInfo | ID: covidwho-20243295

ABSTRACT

This chapter explores the barriers and disruption to community and communication resulting from remote working during the COVID-19 pandemic. The University of Utah's decision to abruptly transition to a fully online model resulted in several communication impacts for staff. First, staff participants received little and inconsistent communication from the University. This caused uncertainty within departments, which trickled down to the students staff serve. Second, this led to staff participants feeling disconnected from the institution and increased their concerns around misinforming students. At the same time, the move to online learning and work decreased efficient communication between colleagues. Casual interactions in the office became email threads and extended feedback processes. Third, staff reported that online communications with students became less personal, which created difficulty for building and maintaining rapport. Finally, staff members' overall sense of community consistently dropped as the COVID-19 pandemic raged on and they were forced to continue to work remotely. The discontent and apprehension felt by staff members around the communication provided from University leadership was compounded by the impact of working from home. (PsycInfo Database Record (c) 2023 APA, all rights reserved)

3.
LC GC North America ; 41(5):181-185, 2023.
Article in English | ProQuest Central | ID: covidwho-20241824

ABSTRACT

[...]instrument-based sample preparation technologies are presented. [...]attention is turned to other sample preparation accessories and supporting technologies. First is the Swift HLB-DPX tips. First is the Thermo Scientific AccelerOme sample preparation platform automating sample preparation for liquid chroma-tography-mass spectrometry (LC-MS) proteomics.

4.
Advances in Nanotechnology for Marine Antifouling ; : 271-302, 2023.
Article in English | Scopus | ID: covidwho-20241760

ABSTRACT

Infectious diseases caused by different pathogens (parasites, protozoa, bacteria, viruses, and fungi) have affected the world at various times in the form of epidemics and pandemics. The coronavirus has also directly affected the world's economy and public health. Various drugs such as antibiotics, antimicrobials, antifungals, and antivirals have been investigated to combat these diseases. However, these fatal infections are still a major concern because of their transmission through contaminated surfaces, human-to-human contact, airborne diffusion, and microbial resistance. Therefore, considerable efforts are required to suppress the transmission of these pathogens. Smart coatings are able to sense their environment and adapt their properties according to the stimulus. Furthermore, various parameters of coating technology can be controlled on a molecular level to influence the morphology. Nanomaterial (NM)-based smart coatings are 99.99% effective against bacteria, viruses, and fungi because of the unique properties of NMs involved. Moreover, NM-based smart coatings are 1000-fold more efficient than traditional coating technologies. Besides their antifungal, antiviral, and antibacterial application, they are anticorrosive and self-cleaning. This chapter summarizes various NM-based smart coatings (organic, inorganic, and carbon) implemented in antibacterial, antifungal, and antiviral applications. Furthermore, the application of these coatings in various fields and their associated challenges will be discussed. © 2023 Elsevier Inc. All rights reserved.

5.
British Food Journal ; 125(6):2190-2216, 2023.
Article in English | CAB Abstracts | ID: covidwho-20240521

ABSTRACT

Purpose: Organic food consumption decreases the risk of becoming obese or overweight. This study intends to see the influence of customer perceived value, COVID-19 fear, food neophobia, effort and natural content on the intention to purchase organic food (IPOF) that leads to the actual purchase of organic food (APOF). Moreover, organic food availability is a moderator between IPOF and APOF. Design/methodology/approach: PLS-SEM is used for hypothesis testing. A purposive sampling technique was followed to gather data from organic food consumers in Lahore, Gujranwala and Islamabad and a total of 479 questionnaires were part of the analysis. Findings The outcomes show that customer perceived value, effort and natural content is positively related to IPOF. Despite this, COVID-19 fear and food neophobia are negatively associated with IPOF. IPOF and organic food availability are positively related to APOF. Finally, organic food availability significantly moderated between IPOF and APOF. Practical implications: This study outcome reveals that companies of organic food can recognize customer perceived value, COVID-19 fear, food neophobia, effort, natural content and organic food availability in their decision-making if they determine the actual purchase of organic food. This study offers a valuable policy to companies of organic food to enhance customer's behavior in purchasing organic food in Pakistan. Besides, practitioners and academicians can benefit from this study finding. Originality/value: This initial research integrates customer perceived value, COVID-19 fear, food neophobia, effort, natural content, IPOF and organic food availability to determine APOF in the COVID-19 pandemic. Moreover, consumption value theory is followed to develop the framework.

6.
Revista Katálysis ; 25(3):551-559, 2022.
Article in Portuguese | ProQuest Central | ID: covidwho-20238909

ABSTRACT

Este artigo tem por objetivo aprofundar o debate sobre a insegurança alimentar durante a pandemia da Covid-19, relatar a iniciativa social extensionista do Plantio Agroecológico Solidário (PAS) da Universidade Federal de Santa Catarina e o consequente impacto no acesso e distribuição de alimentos orgânicos em Florianópolis, SC, Brasil. No contexto da crise sanitária, com mais de 645.000 mortos por Covid-19 no Brasil, aliada à crise econômica, acentuaram-se as desigualdades sociais que aprofundaram o cenário de fome no país. O atual cenário pandêmico indica um momento singular para que a nossa sociedade possa repensar o direito global ao acesso a alimentos saudáveis e sobre qual modelo de agricultura se espera fomentar. A agricultura agroecológica é um modelo viável e necessário para a produção digna e consciente de alimentos, fornecendo mecanismos para a promoção da Soberania e Segurança Alimentar e Nutricional, através da democratização ao acesso a alimentos saudáveis e sem agrotóxicos.Alternate :This article aims it is contribute the debate on food insecurity during the COVID-19 pandemic, to report on the social extension initiative of the Solidarity Agroecological Planting (PAS) of the Federal University of Santa Catarina and the consequent impact on the access and distribution of organic food in Florianopolis, SC, Brazil. In the context of the health crisis, with more than 645,000 deaths from Covid-19 in Brazil, allied to the economic crisis, social inequalities were accentuated that deepened the hunger scenario in the country. The current pandemic scenario indicates a unique moment for our society to rethink the global right to access to healthy food and on which model of agriculture it is expected to promote. Agroecological agriculture is a viable and necessary model for the dignified and conscious production of food, providing mechanisms for the promotion Sovereignty and Food and Nutritional Security, through the democratization of access to healthy and pesticide-free food.

7.
Sustainability ; 15(11):8998, 2023.
Article in English | ProQuest Central | ID: covidwho-20238175

ABSTRACT

The major goal of this study is to trace the emergence of SFC-related research across time, using a thematic map and a list of corresponding publications. In addition, this study aims to determine the author who has made the most significant contribution to this particular field. This study provides a comprehensive bibliometric analysis of the historical development and current trends in sustainable food consumption research, examining 2265 articles published between 1990 and 2023. Using the bibliometrics package of R Studio software version 4.2.1 and its Biblioshiny package, articles from the Scopus and Web of Science databases are examined. In the field of sustainable food consumption, we identify five distinct research phases: initial stagnation, infant growth, post-economic crisis, expanding phase and COVID-19 and post-pandemic. While research on broader sustainability topics can be traced back to the early 20th century, a very limited number of articles on sustainable food consumption was published in the 1990s. However, the number of publications increased incrementally over time, with a notable uptick in interest around 2015, and the subject was still being discussed in 2022. The emergence of the COVID-19 pandemic marked the beginning of the most recent phase of research, which analyzed the consumption patterns of consumers before and after the pandemic. Our study highlights key authors, documents and sources related to sustainable food consumption. The United States, Italy and the United Kingdom emerged as the most active contributors to the research on sustainable food consumption and were additionally the countries with the largest global market shares for organic products. Major sub-themes including organic food, food waste, sustainable development and food security, together with consumer behavior and organic products appeared as being the most researched sub-themes of recent times. The results of this study suggest that more research is related to sustainable food consumption in countries with a low organic food market share. In addition, the investigation of actual data on food waste, carbon footprints and greenhouse gas emissions resulting from food production and consumption is essential to gain holistic insights.

8.
Atmospheric Chemistry and Physics ; 23(11):6217-6240, 2023.
Article in English | ProQuest Central | ID: covidwho-20238090

ABSTRACT

The unprecedented lockdown of human activities during the COVID-19 pandemic has significantly influenced social life in China. However, understanding the impact of this unique event on the emissions of different species is still insufficient, prohibiting the proper assessment of the environmental impacts of COVID-19 restrictions. Here we developed a multi-air-pollutant inversion system to simultaneously estimate the emissions of NOx, SO2, CO, PM2.5 and PM10 in China during COVID-19 restrictions with high temporal (daily) and horizontal (15 km) resolutions. Subsequently, contributions of emission changes versus meteorological variations during the COVID-19 lockdown were separated and quantified. The results demonstrated that the inversion system effectively reproduced the actual emission variations in multi-air pollutants in China during different periods of COVID-19 lockdown, which indicate that the lockdown is largely a nationwide road traffic control measure with NOx emissions decreasing substantially by ∼40 %. However, emissions of other air pollutants were found to only decrease by∼10% because power generation and heavy industrial processes were not halted during lockdown, and residential activities may actually have increased due to the stay-at-home orders. Consequently, although obvious reductions of PM2.5 concentrations occurred over the North China Plain (NCP) during the lockdown period, the emission change only accounted for 8.6 % of PM2.5 reductions and even led to substantial increases in O3. The meteorological variation instead dominated the changes in PM2.5 concentrations over the NCP, which contributed 90 % of the PM2.5 reductions over most parts of the NCP region. Meanwhile, our results suggest that the local stagnant meteorological conditions, together with inefficient reductions of PM2.5 emissions, were the main drivers of the unexpected PM2.5 pollution in Beijing during the lockdown period. These results highlighted that traffic control as a separate pollution control measure has limited effects on the coordinated control of O3 and PM2.5 concentrations under current complex air pollution conditions in China. More comprehensive and balanced regulations for multiple precursors from different sectors are required to address O3 and PM2.5 pollution in China.

9.
Asia Pacific Journal of Marketing and Logistics ; 35(6):1532-1551, 2023.
Article in English | ProQuest Central | ID: covidwho-20237719

ABSTRACT

PurposeThe purpose of this study is to examine the impact of scarcity and the Lifestyles of Health and Sustainability (LOHAS) consumption tendency on the purchase intention of organic foods. The study used the protection motivation theory and the stimulus-organism-response theory to understand the impact of comparatively new variables like "perceived scarcity” and "perceived consumer effectiveness” (PCE) on the consumer's organic food purchase intentions.Design/methodology/approachThe study is using structural equation modeling with 402 organic food consumers. The participants are regular consumers who bought organic food from specialized shops and supermarkets in the previous few months. The data has been collected at organic food specialized shops and supermarkets that sell organic foods.FindingsThe results showed that LOHAS consumption tendency (LCT), scarcity and PCE positively affect attitude. Similarly, LCT and PCE direct affect trust. Scarcity and PCE directly positive impact on purchase intention of organic food products. Interestingly, LCT had no direct impact on the purchase intention of the product. Trust and attitude were found to be significant mediators impacting purchase intention.Originality/valueThe study contributes to the past theoretical literature on LOHAS consumption by analyzing new constructs like scarcity and PCE in the context of organic food consumption. These findings will be crucial for marketers planning to launch organic products in new markets.

10.
Agrociencia ; 57(3):564-588, 2023.
Article in English | Scopus | ID: covidwho-20236792

ABSTRACT

The global showcase for the promotion of the Andean grain quinoa (Chenopodium quinoa Willd.) resulted in a rapid increase in international demand, which has had a direct impact on Peruvian food safety. The excessive use of pesticides results in high levels of pesticide residues in food, causing both environmental and health problems in the population. The objective of this article was to analyze if residues of internationally banned pesticides were present in the quinoa consumed by Peruvians during the COVID-19 pandemic. Twenty-seven different brands of packed white quinoa (10 sold as organically certified and 17 sold as conventional) were purchased in various supermarkets and bio-shops across metropolitan Lima on January 26, 2021. The pesticide residues in the samples were determined in a laboratory. The study found that Peruvian quinoa not only contained residues of internationally banned pesticides, but also had levels that exceed the maximum residue limits (MRLs) established by the European Union. For consumer safety, it is important that the government make the proposed regulations regarding hazardous pesticides clear to the public. © This work is licensed under a Creative Commons Attribution-Non-Commercial 4.0 International license.

11.
Cytotherapy ; 25(6 Supplement):S109, 2023.
Article in English | EMBASE | ID: covidwho-20236255

ABSTRACT

Background & Aim: Liposomes are spherical-shaped vesicles composed of one or more lipid bilayers. The ability of liposomes to encapsulate hydro- or lipophilic drugs allowed these vesicles to become a useful drug delivery system. Natural cell membranes, such as Bioxome, have newly emerged as new source of materials for molecular delivery systems. Bioxome are biocompatible and GMP-compliant liposome-like membrane that can be produced from more than 200 cell types. Bioxome self-assemble, with in-process self-loading capacity and can be loaded with a variety of therapeutic compounds. Once close to the target tissue, Bioxome naturally fuse with the cell membrane and release the inner compound. Orgenesis is interested in evaluating the potential of Bioxome as new drug delivery system for treatment of several diseases, including skin repair, local tumour or COVID19. Methods, Results & Conclusion(s): Bioxome were obtained from adipose- derived Mesenchymal Stem Cells, with a process of organic- solvent lipid extraction, followed by lyophilization and sonication assemblage. During the sonication process, Bioxome were charged or not with several cargos. Size distribution of empty Bioxome was detected by Particle Size Analyzer (NanoSight). Electron Microscopy (EM) was performed to assess Bioxome morphology. Lipid content was evaluated by electrospray ionization system. Dose response in vitro test on human lung fibroblasts treated or not with Bioxome encapsulating a specific cargo (API) against COVID19 were performed. NanoSight analysis showed that nanoparticle size in Bioxome samples ranged between 170+/-50 nm, with a concentration ranging between 109-1010+/-106 particles/mL. EM clearly showed the double phospholipid layers that composes the Bioxome. Stability study demonstrated that Bioxome are stable in size and concentration up to 90 days at +4Cdegree or even at RT. No change in size between encapsulated Bioxome with small size (~340 Da) cargo vs empty Bioxome was observed up to 30 days storage. Lipidomic analysis approach revealed that the yield of lipids and their composition are satisfactory for a therapeutic product using Bioxome. Lastly, in the in vitro model of COVID19, Bioxome encapsulating API effectively saved cells from death (20x vs untreated cells) and at lower doses of API than these of non-encapsulated cargo (0.005 microM vs 0.1 microM). Bioxome seems to be an excellent candidate for liposome mimetic tool as drug delivery system for targeting specific organs and diseases treatment.Copyright © 2023 International Society for Cell & Gene Therapy

12.
IEEE Transactions on Industry Applications ; : 1-7, 2023.
Article in English | Scopus | ID: covidwho-20235410

ABSTRACT

In this paper we report two applications of a subcategory of air cleaning devices based on soft ionization that do not cause molecular fragmentation. A system that includes two unipolar ionizing modules has been used to simultaneously produce positive and negative ions in the air. In one set of experiments a large chamber (28 m3) was used to study the effect of ions on reducing PM1.0 particles produced by a research grade calibrated cigarette. The data presented in this paper were obtained using a carbon-brush-based bipolar ionizer and a MERV 10 filter with electret media in a recirculating HVAC system. Significant improvement in removal rate of fine and ultrafine particles was achieved when using the bipolar ionizer in conjunction with the MERV 10 filter. The second set of experiments were conducted using a 36 m3 chamber, following BSL-3 standards, to study the effect of ions on aerosolized SARS-CoV-2. Results of these investigations reveal the inactivation rate of SARS-CoV-2 are enhanced when ions are introduced in the air;inactivation rates were increased by more than 60%and 90%for ion densities of 10,000/cc and 18,000/cc. IEEE

13.
British Food Journal ; 125(7):2407-2423, 2023.
Article in English | ProQuest Central | ID: covidwho-20234895

ABSTRACT

PurposeThis study explores Greek and Swedish consumers' attitude towards organic food consumption in order to demonstrate possible differences that can be identified based on health and ecological consciousness beliefs rather than demographic factors. The examination of an emerging and a more mature market allow the authors to provide more targeted marketing strategies that possibly increase organic food consumption in both countries.Design/methodology/approachThe authors adopt an econometric approach to the analysis of consumer behavior in relation to organic food consumption in Sweden and Greece. More specifically, the authors examine the motivations and postexperiences of organic food consumers of different socioeconomic profiles in these two countries, one in northern and one in southern Europe. The authors apply an ordered logistic regression analysis model to map out the interaction between consumer attitudes and sociodemographic variables.FindingsThe authors results show that consumers in Sweden more frequently purchase organic foods than consumers in Greece. Environmental protection and ethical values increase the odds for Swedish organic food consumers to buy organic food products. Health consciousness and family well-being are perceived as factors that increase the odds for Greek organic food consumers to buy organic foods. Sociodemographic factors do not play a pivotal role for consumer behavior in relation to organic food in both countries.Originality/valueThis study distinguishes between organic food consumers in two countries with different levels of organic food production and export activity, size of organic market, national organic labeling system and legal definition and standards of organic food. Within these differences, the organic food industry could align its marketing efforts better rather focus on simplistic demographics. The current view unfolds the fact that there are limited studies comparing two European markets at different stages of development and the factors that influence organic food consumer behavior.

14.
Agronomy-Basel ; 13(5), 2023.
Article in English | Web of Science | ID: covidwho-20230896

ABSTRACT

The purpose of this research is to empirically identify the association of the IT literacy of farmers and their profitability through online sales of fresh organic fruits and vegetables during the COVID-19 pandemic. The methodology used in the research is quantitative in nature. A closed-end questionnaire has been used as a survey tool to collect data from Indian farmers. The farmers' IT literacy and attitudes towards organic farming are independent variables, and the frequency of sales of products through online stores and farmers' profitability are the dependent variables. The researcher has attempted to study how the outbreak of COVID-19 has moderated the relationship between the independent and dependent variables. The sample size is 271 farmers who sell their products through online stores. The findings reveal that the farmers' attitude towards organic farming and their IT literacy correlate with the profitability of online sales. Further, the outbreak of the COVID-19 pandemic has moderated the relationship between both the dependent and independent variables. This research will help the government in formulating policies for facilitating farmers to sell their produce through online modes. The study could be further extended by collecting data from farmers from different Asian countries and comparing the results with those of the present research findings.

15.
Ieee Transactions on Electron Devices ; 2023.
Article in English | Web of Science | ID: covidwho-2327611

ABSTRACT

Over the past few decades, the field of organic electronics has depicted proliferated growth, due to the advantageous characteristics of organic semiconductors, such as tunability through synthetic chemistry, simplicity in processing, cost-effectiveness, and low-voltage operation, to cite a few. Organic electrochemical transistors (OECTs) have recently emerged as a highly promising technology in the area of biosensing and flexible electronics. OECT-based biosensors are capable of sensing brain activities, tissues, monitoring cells, hormones, DNAs, and glucose. Sensitivity, selectivity, and detection limit are the key parameters adopted for measuring the performance of OECT-based biosensors. This article highlights the advancements and exciting prospects of OECTs for future biosensing applications, such as cell-based biosensing, chemical sensing, DNA/ribonucleic acid (RNA) sensing, glucose sensing, immune sensing, ion sensing, and pH sensing. OECT-based biosensors outperform other conventional biosensors because of their excellent biocompatibility, high transconductance, and mixed electronic-ionic conductivity. At present, OECTs are fabricated and characterized in millimeter and micrometer dimensions, and miniaturizing their dimensions to nanoscale is the key challenge for utilizing them in the field of nanobioelectronics, nanomedicine, and nanobiosensing.

16.
Sci Total Environ ; 892: 164527, 2023 Sep 20.
Article in English | MEDLINE | ID: covidwho-2328052

ABSTRACT

To prevent the fast spread of COVID-19, worldwide restrictions have been put in place, leading to a reduction in emissions from most anthropogenic sources. In this study, the impact of COVID-19 lockdowns on elemental (EC) and organic (OC) carbon was explored at a European rural background site combining different approaches: - "Horizontal approach (HA)" consists of comparing concentrations of pollutants measured at 4 m a.g.l. during pre-COVID period (2017-2019) to those measured during COVID period (2020-2021); - "Vertical approach (VA)" consists of inspecting the relationship between OC and EC measured at 4 m and those on top (230 m) of a 250 m-tall tower in Czech Republic. The HA showed that the lockdowns did not systematically result in lower concentrations of both carbonaceous fractions unlike NO2 (25 to 36 % lower) and SO2 (10 to 45 % lower). EC was generally lower during the lockdowns (up to 35 %), likely attributed to the traffic restrictions whereas increased OC (up to 50 %) could be attributed to enhanced emissions from the domestic heating and biomass burning during this stay-home period, but also to the enhanced concentration of SOC (up to 98 %). EC and OC were generally higher at 4 m suggesting a greater influence of local sources near the surface. Interestingly, the VA revealed a significantly enhanced correlation between EC and OC measured at 4 m and those at 230 m (R values up to 0.88 and 0.70 during lockdown 1 and 2, respectively), suggesting a stronger influence of aged and long distance transported aerosols during the lockdowns. This study reveals that lockdowns did not necessarily affect aerosol absolute concentrations but it certainly influenced their vertical distribution. Therefore, analyzing the vertical distribution can allow a better characterization of aerosol properties and sources at rural background sites, especially during a period of significantly reduced human activities.


Subject(s)
Air Pollutants , COVID-19 , Humans , Aged , Air Pollutants/analysis , Particulate Matter/analysis , Environmental Monitoring , Seasons , COVID-19/prevention & control , Communicable Disease Control , Respiratory Aerosols and Droplets , Carbon/analysis , China
17.
17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022 ; 2022.
Article in English | Scopus | ID: covidwho-2322794

ABSTRACT

Increased usage of chemical disinfectants during the COVID-19 pandemic may impact the chemical composition of indoor air in residential and commercial buildings. This study characterized gas-phase concentrations of volatile organic compounds (VOCs) during multi-surface disinfection activities in a tiny house research facility. This unique facility provided a controlled, yet realistic environment for simulating whole-building disinfection events. VOCs were measured in real-time (1 Hz) in the bulk air of the tiny house with a proton transfer reaction time-of-flight mass spectrometer (PTR-TOF-MS). In addition, particle number (PN) size distributions were measured with a high-resolution electrical low-pressure impactor (HR-ELPI+). PTR-TOF-MS measurements demonstrate that chemical disinfectant spray products applied to multiple surfaces can substantially increase indoor VOC concentrations. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.

18.
17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022 ; 2022.
Article in English | Scopus | ID: covidwho-2321597

ABSTRACT

Air movement dynamics within three student dormitories were studied with simulated carbon dioxide (CO2) pulse injections to understand SARS-CoV-2 transmission risk. CO2 decay rate, proportion of shared air, and transport time were calculated from dynamic CO2 measurement data within simulated source and adjacent receptor rooms. Applying a Wells-Riley infection risk analysis with these results, the risk of SARS-CoV-2 infection in adjacent rooms ranged from 1% to 58% assuming an average emission rate of 5 quanta per hour and exposure duration of 3.5 days. Door opening status was very influential in resulting risk and vertical transport from source to above rooms was observed in all dormitories. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.

19.
17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022 ; 2022.
Article in English | Scopus | ID: covidwho-2326328

ABSTRACT

Site visits were made to ten (non-healthcare) workplace COVID-19 outbreaks to assess ventilation. Measurements of carbon dioxide (CO2), temperature and humidity were made. Room activity and occupancy was observed, and ventilation management assessed. CO2 readings were used to identify areas of poor air quality, and where possible, airflow measurements were made at ventilation openings and CO2 decay rates were used to estimate ventilation rates. Poorly ventilated, regularly occupied spaces were frequently identified by this work. Measures to reduce transmission risk and improve ventilation included opening windows and reducing room capacities. Attempts at reconfiguration of mechanical ventilation systems were not common. Thermal comfort and heating costs were factors cited that influenced decision making. Overall understanding of ventilation was low and identified a need for simple tools to allow stakeholders to assess their workspaces. © 2022 17th International Conference on Indoor Air Quality and Climate, INDOOR AIR 2022. All rights reserved.

20.
Atmos Environ (1994) ; 308: 119864, 2023 Sep 01.
Article in English | MEDLINE | ID: covidwho-2324584

ABSTRACT

The COVID-19 pandemic promoted strict restrictions to human activities in China, which led to an unexpected increase in ozone (O3) regarding to nitrogen oxides (NOx) and volatile organic compounds (VOCs) co-abatement in urban China. However, providing a quantitative assessment of the photochemistry that leads to O3 increase is still challenging. Here, we evaluated changes in O3 arising from photochemical production with precursors (NOX and VOCS) in industrial regions in Shanghai during the COVID-19 lockdowns by using machine learning models and box models. The changes of air pollutants (O3, NOX, VOCs) during the COVID-19 lockdowns were analyzed by deweathering and detrending machine learning models with regard to meteorological and emission effects. After accounting for effects of meteorological variability, we find increase in O3 concentration (49.5%). Except for meteorological effects, model results of detrending the business-as-usual changes indicate much smaller reduction (-0.6%), highlighting the O3 increase attributable to complex photochemistry mechanism and the upward trends of O3 due to clear air policy in Shanghai. We then used box models to assess the photochemistry mechanism and identify key factors that control O3 production during lockdowns. It was found that empirical evidence for a link between efficient radical propagation and the optimized O3 production efficiency of NOX under the VOC-limited conditions. Simulations with box models also indicate that priority should be given to controlling industrial emissions and vehicle exhaust while the VOCs and NOX should be managed at a proper ratio in order to control O3 in winter. While lockdown is not a condition that could ever be continued indefinitely, findings of this study offer theoretical support for formulating refined O3 management in industrial regions in Shanghai, especially in winter.

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