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1.
J Clin Med ; 11(7)2022 Mar 23.
Article in English | MEDLINE | ID: covidwho-2163449

ABSTRACT

SARS-CoV-2 is a virus that causes severe respiratory distress syndrome. The pathophysiology of COVID-19 is related to the renin-angiotensin system (RAS). SARS-CoV-2, a vector of COVID-19, uses angiotensin-converting enzyme 2 (ACE-2), which is highly expressed in human lung tissue, nasal cavity, and oral mucosa, to gain access into human cells. After entering the cell, SARS-CoV-2 inhibits ACE-2, thus favouring the ACE/Ang II/angiotensin II type 1 receptor (AT1R) axis, which plays a role in the development of acute lung injury (ALI). This study aimed to analyse the influence of angiotensin 1 receptor (AT1R) levels in the serum on the course of the severity of symptoms in healthcare professionals who had a SARS-CoV-2 infection. This prospective observational study was conducted on a group of 82 participants. The study group included physicians and nurses who had a COVID-19 infection confirmed by real-time reverse transcription-polymerase chain reaction (RT-PCR) test for SARS-CoV-2. The control group consisted of healthy medical professionals who had not had a SARS-CoV-2 infection or who had no symptoms of COVID-19 and who tested negative for SARS-CoV-2 on the day of examination. We analysed the correlation between AT1R concentration and the severity of COVID-19, as well as with sex, age, blood group, and comorbidities. There were no statistically significant differences in the mean values of AT1R concentration in the recovered individuals and the non-COVID-19 subjects (3.29 vs. 3.76 ng/mL; p = 0.32). The ROC curve for the AT1R assay showed an optimal cut-off point of 1.33 (AUC = 0.44; 95% CI = 0.32-0.57; p = 0.37). There was also no correlation between AT1R concentration and the severity of symptoms associated with COVID-19. Blood type analysis showed statistically significantly lower levels of AT1R in COVID-19-recovered participants with blood group A than in those with blood group O. In conclusion, AT1R concentration does not affect the severity of symptoms associated with COVID-19 among healthcare professionals.

2.
Criminology & Public Policy ; : 1, 2022.
Article in English | Academic Search Complete | ID: covidwho-2161498

ABSTRACT

Research summary Policy implications Inspired by studies on crime concentration, scholars have begun examining the spatial patterns of other issues under the police mandate, such as calls for service involving persons with perceived mental illness (PwPMI). While findings show that PwPMI calls for service concentrate in a few number of places, we do not know whether the concentration of these calls fall within a narrow bandwidth of spatial units nor whether these calls are spatially stable. Drawing on 7 years of calls for service data from the Barrie Police Service, this study tests for the temporal stability of PwPMI call for service concentrations at two units of spatial analysis and applies a longitudinal variation of the Spatial Point Pattern Test to assess the spatial stability of these calls at both the global and local levels. The results reveal that concentrations of PwPMI calls for service not only fall within a narrow proportional bandwidth of spatial units, but are spatially stable, even during the COVID‐19 pandemic.Existing police‐ and community‐based efforts that respond to PwPMI in the community are tasked with responding to crises that could have been prevented with timelier intervention. Drawing from crime‐focused, place‐based policing strategies whose deployment is informed by the spatial concentration of crime, scholars have similarly argued that knowledge on where PwPMI calls for service concentrate can be leveraged to inform and deploy place‐based efforts whose focus is to assist PwPMI in a proactive capacity. The findings of the present study further substantiates the deployment of PwPMI‐focused police‐ and community‐based resources as proactive, place‐based efforts. In doing so, these efforts could not only prevent mental health crises from occurring but could prevent future police‐involved calls for service and thus reduce the footprint of the police in the lives of PwPMI in a reactive capacity. [ FROM AUTHOR]

3.
European Psychiatry ; 65(Supplement 1):S29, 2022.
Article in English | EMBASE | ID: covidwho-2153781

ABSTRACT

Recently, many reports have been available related to neuropsychiatric complications in the course of COVID-19 infection, and its long-term consequences. Many of them are related to psychological factors, such as: isolation, change of existing habits, fear of getting sick and dying, fear of losing a job and fears related to the financial situation, which resulted in an increase in the occurrence of diseases and mental disorders such as adaptation and anxiety disorders, depression. t has been also reported that treatment in conditions of intensive care unit lead to high prevalence of psychiatric disorders like PTSD in discharged patients. In our own studies we observed that patients with new appearing psychiatric symptoms were mostly those, who were professionally active, but did not work remotely. The time the patients spent at home had a negative impact on their well-being, they generally felt worse, their family life suffered more frequently. The most common cognitive symptoms, which are reported embrace: problems with short- and longterm memory, lack of mental clarity, feeling eclipsed, lightheaded, poor concentration, mental fatigue. We also present here a series of post-acute COVID cases from the examined population and provide a concise comparison of observed symptomatology with previous reports.

4.
Ieee Access ; 10:121204-121229, 2022.
Article in English | Web of Science | ID: covidwho-2152418

ABSTRACT

In this paper, curve-fitting and an artificial neural network (ANN) model were developed to predict R-Event. Expected number of new infections that arise in any event occurring over a total time in any space is termed as R-Event. Real-time data for the office environment was gathered in the spring of 2022 in a naturally ventilated office room in Roorkee, India, under composite climatic conditions. To ascertain the merit of the proposed ANN and curve-fitting models, the performances of the ANN approach were compared against the curve fitting model regarding conventional statistical indicators, i.e., correlation coefficient, root mean square error, mean absolute error, Nash-Sutcliffe efficiency index, mean absolute percentage error, and a20-index. Eleven input parameters namely indoor temperature ( $T_{In}$ ), indoor relative humidity ( $RH_{In}$ ), area of opening ( $A_{O}$ ), number of occupants ( $O$ ), area per person ( $A_{P}$ ), volume per person ( $V_{P}$ ), $CO_{2}$ concentration ( $CO_{2}$ ), air quality index ( $AQI$ ), outer wind speed ( $W_{S}$ ), outdoor temperature ( $T_{Out}$ ), outdoor humidity ( $RH_{Out}$ ) were used in this study to predict the R-Event value as an output. The primary goal of this research is to establish the link between $CO_{2}$ concentration and R-Event value;eventually providing a model for prediction purposes. In this case study, the correlation coefficient of the ANN model and curve-fitting model were 0.9992 and 0.9557, respectively. It shows the ANN model's higher accuracy than the curve-fitting model in R-Event prediction. Results indicate the proposed ANN prediction performance (R = 0.9992, RMSE = 0.0018708, MAE = 0.0006675, MAPE = 0.8643816, NS = 0.9984365, and a20-index = 0.9984300) is reliable and highly accurate to predict the R-event for offices.

5.
IOP Conference Series Earth and Environmental Science ; 1102(1):012046, 2022.
Article in English | ProQuest Central | ID: covidwho-2151800

ABSTRACT

Malaysia is currently facing the COVID-19 pandemic which has claimed hundreds of innocent lives. Because of the health problems impose by the pandemic, the government has ordered to implement the movement control order (MCO) starting March 18, 2020. With this movement control order in place, people are not allowed to leave the house. Therefore, movement on the road can also be reduced. This study was conducted to investigate the emission concentrations of ground-level ozone into the air during MCOs in an urbanized area of Shah Alam. This secondary data of ground-level ozone (O3) was acquired from the Department of Environment in 2020 and interpreted using the methods of box and whisker plot, time series analysis, and diurnal variation plot. The results found that the concentrations of air pollutants in each type of MCOs implemented were different in terms of trends. During the early implementations of MCOs, results showed that there was a slight decrement in O3 concentrations and as MCOs periods continued, there higher decrements in O3 concentrations were observed. During the MCOs period, non-exceedance episodes were recorded which show the level of ground-level ozone was significantly improved result of the implementation of MCOs. Results also suggested there is a shift in the peak concentration time as the plot showed peak concentrations were reached between 4 to 6 p.m. which is quite later as normally peaks O3 concentrations were reported normally reached from 12 noon to 2 p.m. [13]

6.
TrAC Trends in Analytical Chemistry ; : 116880, 2022.
Article in English | ScienceDirect | ID: covidwho-2150707

ABSTRACT

As the recent coronavirus disease (COVID-19) pandemic and several severe illnesses such as Middle East respiratory syndrome coronavirus (MERS-CoV), Influenza A virus (IAV) flu, and severe acute respiratory syndrome (SARS) have been found to be airborne, the importance of monitoring bioaerosols for the control and prevention of airborne epidemic diseases outbreaks is increasing. However, current aerosol collection and detection technologies may be limited to on-field use for real-time monitoring because of the relatively low concentrations of targeted bioaerosols in air samples. Microfluidic devices have been used as lab-on-a-chip platforms and exhibit outstanding capabilities in airborne particulate collection, sample processing, and target molecule analysis, thereby highlighting their potential for on-site bioaerosol monitoring. This review discusses the measurement of airborne microorganisms from air samples, including sources and transmission of bioaerosols, sampling strategies, and analytical methodologies. Recent advancements in microfluidic platforms have focused on bioaerosol sample preparation strategies, such as sorting, concentrating, and extracting, as well as rapid and field-deployable detection methods for analytes on microfluidic chips. Furthermore, we discuss an integrated platform for on-site bioaerosol analyses. We believe that our review significantly contributes to the literature as it assists in bridging the knowledge gaps in bioaerosol monitoring using microfluidic platforms.

7.
45th Mexican Conference on Biomedical Engineering, CNIB 2022 ; 86:843-850, 2023.
Article in English | Scopus | ID: covidwho-2148593

ABSTRACT

In this work, CO2 levels were estimated in the naso-buccal area due to the use of face masks. Tests were performed on a healthy volunteer subject sitting at rest and breathing regularly, who used five types of face masks in well-ventilated and poorly ventilated rooms. The ventilation conditions were determined by the natural ventilation of the room. Each of the tests lasted one hour. To estimate the CO2 level, a sensor based on the Non-dispersive Infrared (NDIR) principle was used. The results revealed that while wearing a face mask, the ventilation conditions affected the CO2 concentration levels in the naso-buccal area of the user, especially in those that offered a higher level of protection, and in those that best fit the face of the subject. A multiple comparison method (Tukey) revealed significant differences in the levels of CO2 between all the facemask tested (p < 0.0001). The CO2 levels were also compared with the exposure limits recommended by NIOSH, showing that the use of N95 for 1 h exceeded the recommended 5,000 ppm for an 8-h workday. None of the masks tested exceeded the NIOSH-recommended short-term limit in the first 15 min of use. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

8.
Beijing Gongye Daxue Xuebao/Journal of Beijing University of Technology ; 48(11):1168-1174, 2022.
Article in Chinese | Scopus | ID: covidwho-2145244

ABSTRACT

The air pollution characteristics were analyzed during the coronavirus disease (COVID-19) in Beijing. The hybrid single particle lagrangian integrated trajectory (Hysplit), potential source contribution function (PSCF), and concentration weighted trajectory (CWT) were also applied to study the main transport pathways and potential source regions of air masses during heavy pollution. Results show that compared with before COVID-19 (January 1-22, 2020) and the same period of 2019, the concentration of PM2.5 (aerodynamic diameter of <2.5 μm) after COVID-19 (January, 23-31, 2020) increased by 149.7% and 62.2%, respectively, while increased by 40.6% and 6.8% for sulfur dioxide (SO2), 42.6% and 37.8% for carbon monoxide (CO), and 73.6% and 28.0% for ozone (O3). Nitrogen dioxide (NO2) concentrations after COVID-19 decreased by 27.9% and 21.6%, respectively, compared with before COVID-19 and the same period of 2019. The most polluted day in January 28 was selected to analyze the backward trajectory and potential source regions. The air masses from the surrounding of Beijing were the main transport pathways of heavy pollution episode. The main potential source regions mainly concentrated in Beijing, northern Langfang, and northern Tianjin. The long-distance transmission from central and western Inner Mongolia and northern Beijing had little impact on this heavy pollution episode. Therefore, it is still necessary to conduct the regional joint prevention and control to improve the air quality in Beijing. © 2022, Editorial Department of Journal of Beijing University of Technology. All right reserved.

9.
Promet - Traffic - Traffico ; 34(5):789-800, 2022.
Article in English | Scopus | ID: covidwho-2144973

ABSTRACT

The extreme traffic measures during the COVID-19 lockdown provided a unique opportunity to gain better insight into the relationship between traffic characteristics and NO2 concentrations in Maribor, a small Slovenian city. NO2, traffic and meteorological data were sta-tistically processed in detail for March and April 2018, 2019 and 2020 to get a historical insight and to exclude the specifics of the lockdown period. The extreme event resulted in an average reduction of road traffic of 42%. The decrease in the number of passenger cars ranged from 33.9 to 60.3% per day with the largest decrease on the motorway. Daily averages of heavy goods traffic de-clined on the motorway and the expressway by 24.6% and 7%, respectively. Traffic characteristics were reflect-ed in a 24–27% decrease in NO2 concentrations at the urban station. The change is smaller than the change in traffic volume, which could be explained by the change in the composition of the vehicle fleet due to the increase in NO2-dominant traffic sources, e.g. diesel heavy goods vehicles. The presented results are relevant for improving air quality and sustainable mobility management in small cities. They highlight the important role of reor-ganisation of heavy goods traffic in urban logistics. © 2022, Faculty of Transport and Traffic Engineering. All rights reserved.

10.
Pharmacia ; 69(4):981-985, 2022.
Article in English | Scopus | ID: covidwho-2143921

ABSTRACT

Bacterial resistance is a difficult limitation in the treatment of infections. The potential antibacterial activity of WOW peptide conjugation with silver nanoparticles against selected pathogens is investigated in this study. The peptide WOW was created by combining two tryptophan subunits and one ornithine amino acid, and its purity was determined using reverse phase high performance liquid chromatography. Mass spectrometry and electrospray ionization mass spectrometry were used to confirm the WOW peptide. Silver nanoparticles conjugated with WOW were created by adding WOW to a solution of silver nitrate in the presence of the reducing agent sodium borohydride. The yellow-brown color indicated the presence of WOW-AgNPs, which was confirmed by ultraviolet/ visible spectrophotometry. The minimum inhibitory and bactericidal concentrations of WOW nanoparticles were determined using the micro dilution method against Staphylococcus aureus, Escherichia coli, Methicillin resistant Staphylococcus aureus (MRSA), and ESBL Escherichia coli. The Erythrocyte Hemolytic Assay was used to assess the toxicity of nanoparticles conjugated with WOW. WOW alone was effective (MICs between 120 and 215 µgml-1) against both standard and resistant strains of bacteria. WOW –AgNPs, on the other hand, were more effective, with MICs ranging from 30 to 100 µgml-1 depending on the bacteria used. WOW -–after 30 minutes of incubation, silver nanoparticles at a concentration of 100 µgml-1 caused only 3% hemolysis in human erythrocytes.in conclusion, WOW –silver nanoparticles were found to have good antibacterial activity against pathogenic strains of gram positive and gram negative bacteria. Furthermore, the conjugate demonstrated low hemolytic activity and cytotoxicity. As a result, WOW conjugation with AgNPs is a promising treatment candidate for bacterial infection with low toxicity. © copyright salama ah. this is an open access article distributed under the terms of the creative commons attribution license (cc-by 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

11.
2nd International Conference on Testing Technology and Automation Engineering, TTAE 2022 ; 12457, 2022.
Article in English | Scopus | ID: covidwho-2137338

ABSTRACT

The hospital room is the first line of assistance to patients, to ensure the comfort of doctors and patients at the same time, but also to ensure the protection of the personal safety of doctors and patients. For this reason, a good airflow organization helps to reduce the concentration of respiratory particles in the whole space and also creates a comfortable environment. Based on the CFD theory of computational fluid dynamics, ANSYS Fluent software is used to simulate the clinic environment, and four airflow organizations are used as the research objects, and the temperature cloud map, air age, and draft rate (DR) are used as the evaluation indexes, while the particulate matter concentration in the clinic is analyzed, and the 10 main indexes for evaluating the clinic environment are subjected to the principal component analysis algorithm (PCA), the four airflow organizations are comprehensive ranking. Since the traditional questionnaire has a lot of human subjectivity, using the algorithm can effectively compensate for the shortcomings of the questionnaire, and comparing the conclusions derived from the PCA algorithm with the results of the questionnaire can make the conclusions more scientific. The final conclusion is that the airflow organization of the replacement air supply can meet human comfort and air freshness while reducing the concentration of respiratory particulate matter in the clinic environment under the evaluation of various indexes, for which the replacement air supply scheme can provide a theoretical basis and reference for future construction implementation. © 2022 SPIE.

12.
Egyptian Journal of Soil Science ; 61(4):445-457, 2021.
Article in English | Web of Science | ID: covidwho-2124174

ABSTRACT

Upon the outbreak and spreading of COVID-19, several reduction measures have been implemented throughout the world to avert the COVID-19 pandemic risks such as entire lockdowns, social distancing, extensive travel bans, mass quarantines, etc. Many positive and negative indicators of this pandemic on the whole environmental compartments have been reported worldwide. These indicators may include promoting the air quality through a reduction in anthropogenic-based emissions (e.g., CO2 and N2O) and increase ozone concentration in addition to energy, water and wastewater, deforestation, and natural resources. This is the difficult equation concerningthe COVID-19 pandemic outbreak and its health, societal, economic, and environmental risks and how is the recovery of the environment? Is this recovery will be permanent or temporary? The answer to this question may be emphasized during the outcoming days or months. What will increase this global pandemic aggravation if the COVID-19 has appeared in many types, which enforce us to re-think again concerning the task?

13.
Theoretical and Practical Issues of Journalism ; 11(1):76-85, 2022.
Article in Russian | Web of Science | ID: covidwho-2124131

ABSTRACT

The Norwegian media system has a variety of media outlets. However, historically, it was newspapers that were the most demanded and popular media among Norwegians. Newspaper became the basic assets of Norway's first media groups. In 2020, three media companies were represented on the newspaper market: Shibstead, Amedia, and Polaris Media. The research is an analytical study of the Norwegian newspaper market during the COVID-19 pandemic. The purpose of the study was to identify the main trends in the development of the Norwegian newspaper market during the pandemic. The results of the analysis Norwegian newspaper market in 2020 showed that, firstly, one of the main trends has become the concentration of media assets, which is increasing every year, and in 2020 its predominance was facilitated by changes in media regulation. Secondly, the pandemic has accelerated the digitalization of newspapers, which has affected the growth of digital circulation, and, as a result, has a beneficial effect on the revenues of media companies, as well as the government strategy for the transition to digital media. Third, advertising revenues of offline newspapers continued to decline, but none of newspapers closed, and operating profit of media companies increased compared to 2019. Thus, despite the restrictions associated with the pandemic, the trends in the development of the Norwegian newspaper market were associated mainly with the strengthening of trends that formed earlier, and not of those that were a result of the COVID-19 pandemic. The empirical base of the study was the reports for 2020 of the Norwegian Media Office, the Statistics Bureau of Norway, reports of S. Hirst on researching the Norwegian newspaper market, reports of the media companies Shibsted, Amedia, Polaris Media.

14.
Biochem Biophys Rep ; : 101395, 2022 Nov 23.
Article in English | MEDLINE | ID: covidwho-2122336

ABSTRACT

Previous data have suggested an antiviral effect of teriflunomide, including against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the agent underlying the ongoing COVID-19 pandemic. We undertook an in vitro investigation to evaluate the inhibitory activity of teriflunomide against SARS-CoV-2 in a cell-based assay. Teriflunomide was added to Vero (kidney epithelial) cells that had been infected with SARS-CoV-2. A nucleocapsid immunofluorescence assay was performed to examine viral inhibition with teriflunomide and any potential cytotoxic effect. The 50% effective concentration (EC50) for teriflunomide against SARS-CoV-2 was 15.22 µM. No cytotoxicity was evident for teriflunomide in the Vero cells (i.e., the 50% cytotoxic concentration [CC50] was greater than the highest test concentration of 100 µM). The data were supported by additional experiments using other coronaviruses and human cell lines. In the SARS-CoV-2-infected Vero cells, the prodrug leflunomide had an EC50 of 16.49 µM and a CC50 of 54.80 µM. Our finding of teriflunomide-mediated inhibition of SARS-CoV-2 infection at double-digit micromolar potency adds to a growing body of evidence for a broad-ranging antiviral effect of teriflunomide.

15.
United European Gastroenterology Journal ; 10(Supplement 8):241, 2022.
Article in English | EMBASE | ID: covidwho-2115473

ABSTRACT

Introduction: There are seven types of coronaviruses that are known to infect humans, including three highly pathogenic members MERS-CoV, SARS-CoV-1 and SARS-CoV-2, and four seasonal coronaviruses, including NL63, 229E, OC43 and HKU1. Immunocompromised populations, such as organ transplant recipients receiving immunosuppressive medications and patients with inflammatory bowel disease treated with immunosuppressive or immunomodulatory therapies, are in general more susceptible to coronavirus infections. However, little is known how immunosuppressants directly affect coronavirus infection. Aims & Methods: This study aims to profile the effects of immunosuppressants and the combination of immunosuppressants with oral antiviral drug molnupiravir and nirmatrelvir on pan-coronavirus infection in cell culture models. Different coronaviruses (including wild type, delta and omicron variants of SARS-CoV-2, NL63, 229E and OC43) were used in cell culture models. The effects of immunosuppressants including dexamethasone, budesonide, prednisolone, sulfasalazine, aminosalicylates, 6-thioguanine, azathioprine, 6-mercaptopurine, methotrexate, tacrolimus, cyclosporine A, mycophenolic acid (MPA), rapamycin, everolimus, tofacitinib and figotinib on coronavirus infections, and the combination with molnupiravir and nirmatrelvir were studied in cell culture. Result(s): To profile the effect of immunosuppressants, we first tested all these regimens at 1 muM on wild type SARS-CoV-2, and then validated on different coronaviruses. We found dexamethasone and aminosalicylates can significantly stimulate the replication of these coronaviruses. For example, treatment with 1 muM dexamethasone significantly increased virus RNA level of wild type SARS-CoV-2 by 137+/-40%. 6-thioguanine, MPA, tofacitinib and figotinib treatment inhibited viral replication in a dosedependent manner in all tested coronaviruses. 6-thioguanine at 1 muM concentration had already potently inhibited the replication of wild type SARS-CoV-2 by 95+/-16%. The half maximum effective concentration (EC50) of tofacitinib against wild type SARS-CoV-2 replication was 0.60 muM and the half maximum cytotoxic concentration (CC50) was above 30 muM, which resulted in a selective index (SI) above 50. Combination treatment is often used to enhance antiviral efficacy, avoid drug resistance development in clinical applications. We evaluated the combined antiviral effects of 6-thioguanine, MPA and tofacitinib with molnupiravir and nirmatrelvir in wild type SARS-CoV-2 infection model. The combination of tofacitinib with molnupiravir had a moderate additive effect with the ZIP synergy score of 7, whereas the other two combinations had no such effect. However, the combination of MPA, 6-thioguanine, and tofacitinib with nirmatrelvir resulted in strong synergistic effect, and the ZIP synergy scores were 31, 22 and 12 respectively. Conclusion(s): These results demonstrated that different immunosuppressants had differential effects on coronavirus replication. 6-thioguanine, MPA, tofacitinib and figotinib were identified as potent inhibitors against pan-coronavirus infections. Although combination of MPA, 6-thioguanine, and tofacitinib with molnupiravir exerted moderate additive effect, combination with nirmatrelvir exerted strong synergistic antiviral activity. Thus, these findings provide as an important reference for clinicians to choose the optimal immunosuppressants for coronavirus infected immunocompromised patients or when they are under antiviral treatment of molnupiravir or nirmatrelvir.

16.
Sci Total Environ ; : 160072, 2022 Nov 07.
Article in English | MEDLINE | ID: covidwho-2105908

ABSTRACT

In this study, two virus concentration methods, namely Adsorption-extraction (AE) and Nanotrap® Magnetic Virus Particles (NMVP) along with commercially available extraction kits were used quantify endogenous pepper mild mottle virus (PMMoV) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in nucleic acid extracted from 48 wastewater samples collected over six events from eight wastewater treatment plants (WWTPs). The main aim was to determine which workflow (i.e., concentration and extraction methods) produces greater concentrations of PMMoV and SARS-CoV-2 gene copies (GC) in comparison with each other. Turbidity and total suspended solids (TSS) of wastewater samples within and among the eight WWTPs were highly variable (41-385 NTU and 77-668 mg/L TSS). In 58 % of individual wastewater samples the log10 GC concentrations of PMMoV were greater by NMVP workflow compared to AE workflow. Paired measurements of PMMoV GC/10 mL from AE and NMVP across all 48 wastewater samples were weakly correlated (r = 0.455, p = 0.001) and demonstrated a poor linear relationship (r2 = 0.207). The log10 GC concentrations of SARS-CoV-2 in 69 % of individual samples were greater by AE workflow compared to NMVP workflow. In contrast to PMMoV, the AE and NMVP derived SARS-CoV-2 GC counts were strongly correlated (r = 0.859, p < 0.001) and demonstrated a strong linear relationship (r2 = 0.738). In general, the PMMoV GC achieved by the NMVP workflow decreased with increasing turbidity, but the PMMoV GC by the AE workflow did not appear to be sensitive to either turbidity or TSS levels. These findings suggest that suspended solids concentration, and the intended target for analysis should be considered when validating an optimal workflow for wastewater surveillance.

17.
Sci Total Environ ; 859(Pt 1): 160012, 2022 Nov 09.
Article in English | MEDLINE | ID: covidwho-2105904

ABSTRACT

AIMS: This paper aims to review the main sludge concentration methods used for SARS-CoV-2 detection in sewage sludge samples, discussing the main methods and sample volume related to increased viral load. In addition, we aim to evaluate the countries associated with increased positivity rates for SARS-CoV-2 in sludge samples. METHODS: This systematic methodology was registered in PROSPERO and followed the PRISMA guidelines. The search was carried out in the SciELO, PubMed/MEDLINE, Lilacs, and Google Scholar databases in January-March 2022. Quantitative studies with conclusive results were included in this review. Concentration methods (polyethylene glycol (PEG), PEG + NaCl, gravity thickening, skimmed milk flocculation, ultrafiltration, filtration using charged filters, primary sedimentation, and anaerobic digestion), as well as detection methods (RTqPCR and reverse transcription droplet digital PCR assay) were evaluated in this review. The SPSS v23 software program was used for statistical analysis. RESULTS: PEG (with or without NaCl addition) and gravity thickening were the most used sludge concentration methods to detect SARS-CoV-2. The main method associated with increased viral load (>2,02 × 10^4 copies/mL) was PEG + NaCl (p < 0.05, Mann-Whitney test). The average positivity rate for SARS-CoV-2 in sludge samples was 61 %, and a correlation was found between the sludge volume and the viral load (ro 0.559, p = 0.03, Spearman correlation). CONCLUSION: The sludge volume may influence the SARS-CoV-2 load since the virus can adhere to solid particles in these samples. Other factors may be associated with SARS-CoV-2 load, including the methods used; especially PEG + NaCl may result in a high viral load detected in sludge, and may provide a suitable pH for SARS-CoV-2 recovery.

19.
Atmosphere ; 13(10), 2022.
Article in English | Web of Science | ID: covidwho-2099315

ABSTRACT

Various methods used by different countries' governments to control the spread of coronavirus disease 2019 (COVID-19), the cause of pandemic in 2020, affected air quality. The aim of this study was to evaluate the effects of lockdown in Armenia on the content of the main air pollutants-dust, SO2 and NO2. This was a cross-sectional study. We analyzed data on the concentrations of SO2, NO2 and dust from March to June, 2019 and the same period in 2020 as well as data on positive COVID-19 cases from Yerevan, Vanadzor and Hrazdan. In 2020, dust was found to be lower in Yerevan and in Hrazdan and higher in Vanadzor than in the same period in 2019. The same pattern was present for SO2 concentrations: in Yerevan and Hrazdan there was a decrease, and there was an increase in Vanadzor. The concentrations of NO2 increased in Yerevan and Hrazdan, with a slight decrease in Vanadzor. New cases of COVID-19 had a negative correlation with dust and a positive correlation with SO2. The strict quarantine measures were effective in containing the spread of COVID-19.

20.
Frontiers in Environmental Science ; 10, 2022.
Article in English | Web of Science | ID: covidwho-2083024

ABSTRACT

A series of lockdown measures in response to the Corona Virus Disease 2019 (COVID-19) outbreak resulted in a drop in anthropogenic emissions and changes in concentrations of PM2.5 and O-3. Backward trajectories analysis, cluster analysis, potential source contribution function (PSCF) and concentration weighted trajectory (CWT) technologies were conducted to reveal the characteristics and potential source areas of pollutants in Beijing before the COVID-19 outbreak (BCO period), during the outbreak (COB period) and after the outbreak (ACO period), as well as the contemporaneous period in 2019 (CCO period), which is critical for exploring the efficient control measures and making policy. The results indicated that despite the significant reduction in anthropogenic emissions during the epidemic, the PM2.5 concentrations increased by 1.0% caused by unfavorable meteorological conditions. O-3 concentrations increased by 174.8% compared to that during the BCO period due to the increased temperature and inappropriate precursor reduction ratios. A considerable decrease of NO3- in PM2.5 was observed under the influence of significant reductions in vehicle emissions during the lockdown. The cluster analysis revealed that short-range transport played a significant role in the accumulation of local PM2.5 pollution, while long-range northwest airflows contributed more to O-3 accumulation, and weakened as the season changed. The PSCF and CWT analysis demonstrated that potential source areas of PM2.5 were mostly located in the central and southern Hebei, the southwestern Shandong in the CCO period, and expanded to central Inner Mongolia and northern Shanxi in the COB period. These areas were highly compatible with the high emission areas of the emission inventory statistics. After the outbreak, the source areas of O-3 were centered in the Beijing-Tianjin-Hebei region and Shandong province, with a radial dispersion in all directions, while they were distributed in the central Mongolia and Inner Mongolia during the other periods.

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