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1.
Chemical Engineering Transactions ; 94:259-264, 2022.
Article in English | Scopus | ID: covidwho-2099086

ABSTRACT

The existing COVID-19 pandemic has driven personal protective equipment use and consumption surge, leading to plastic pollution as most waste goes to landfills. Biodegradable polypropylene (PP) gowns claimed to have similar production costs as standard PP film ones might be more environmentally friendly due to the degradability after landfilling. The illustration of their sustainable end-of-life waste disposal options is lacking and requires a systematic comparison of their environmental impacts. A holistic life cycle assessment approach based on full-spectrum environmental indicators identifies the environmentally sustainable waste disposal options. Results illustrate the environmental benefits of landfill gas capture and utilization incorporated to landfilling biodegradable gown wastes by reducing 48.81 % land-use, 9.35 % greenhouse gas emissions from fossil sources, and 5.67 % from land-use greenhouse gas emissions, respectively. Despite these environmental advantages, industrial composting embodies lower environmental emissions than sanitary landfills for treating biodegradable gowns. Fossil-based gowns treated by landfills can have lower environmental impacts than composting biodegradable gowns in full-spectrum environmental indicators. The standard gown landfilling is identified as the environmentally sustainable disposal option. Copyright © 2022, AIDIC Servizi S.r.l.

2.
Kexue Tongbao/Chinese Science Bulletin ; 67(30):3565-3579, 2022.
Article in Chinese | Scopus | ID: covidwho-2098648

ABSTRACT

As emerging pollutants, microplastics (MPs) are widely distributed in water, soil and atmosphere, and have become a popularly concerned environmental and social issue. The research on atmospheric microplastics (AMPs) started later than that on the MPs in soil and water, but AMPs’ potential environmental impacts are explored in an even wider range. Based on the literatures on AMPs since 2015 as well as those about MPs in water and soil, this paper systematically reviews the distribution, source, transport of AMPS and the environmental and ecological impacts of AMPs. The results show that AMPs are distributed in global atmosphere, and have been detected in the atmosphere of urban, suburban, remote areas and indoor air. The concentrations of AMPs were detected in a range 2 to 77000 n m–2 d–1 or 0 to 1583 n m–3. The distribution characteristics of MPs in atmosphere are affected by environmental factors such as indoor and outdoor environment, underlying surface type and airflow, etc. In general, the concentration and the diversity of AMPs’ shape and composition are higher in the places near to MPs the source, but the wind, precipitation and even local animals could reshape the characters of AMPs. The sources of AMPs are mainly the production, use and recycling processes of plastic products, as well as land and sea where MPs accumulated. Studies also showed that abrasion of vehicle tires and the use of synthetic textile are major sources. What’s noteworthy is that the COVID-19 pandemic has made masks as necessities of life, which indirectly exacerbated the pollution of AMPs. The transport of MPs can occur in atmospheric environment, such as suspension, deposition and diffusion, and is affected by the morphology of MPs, wind direction, precipitation and other atmospheric factors. The diffusion of MPs in atmosphere, also known as atmospheric transport, is an important part of the global plastic cycle. AMPs’ transport path is mostly studied of Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) by conducting backward trajectory simulation, and their transport volume is estimated mainly through deposition and aerodynamic model. In addition, AMPs have unique physical and chemical properties, which can affect regional atmospheric environmental quality, change regional and global climate. It could also adsorb heavy metals, organic pollutants and harmful microorganisms during transport, resulting in greater health risks to human. Also, AMPs could affect atmospheric ecosystems through food chains and providing microbial niches, and alter structure and functions of terrestrial forest and water ecosystems through deposition. There are still some unsolved scientific and technical questions. Due to the lack of standardized sampling and identification means, the past research methods on AMPs are different on sampling and physical analysis, which make information comparison difficult. The observations of AMPs’ environmental behaviors, the atmospheric transport, source attribution and trans-regional effects of AMPs are still limited. Therefore, some conclusions from laboratory researches cannot fully explain the uncertainty of in natural environment. Based on the analysis, it is suggested that future scientific research on AMPs should focus on standardization of research methods, the establishment of source list, transport mechanism and environmental and ecological impacts. It is necessary for the study of AMPs to establish a set of scientifically credible and technically feasible monitoring techniques as well. Because AMPs could be transported to different ecosystems and could enter the human body through a variety of ways, it is urgent to study the physiological and ecological status of human body and ecosystems which are continuously exposed to AMPs pollution. © 2022 Chinese Academy of Sciences. All rights reserved.

3.
Chinese Medical Ethics ; 35(9):1028-1034, 2022.
Article in Chinese | Scopus | ID: covidwho-2090895

ABSTRACT

As an important part of Chinese history and culture, traditional medicine is the sum of diagnosis and treatment knowledge, skills and practice methods that have been verified to be effective and of great value through thousands of years of practice. Since the global outbreak of the COVID-19 epidemic, “traditional medicine” has flourished in China, but has also been doubted by different cultural fields overseas. Based on traditional medicine, facing the realistic situation of “ice and fire”, focusing on the contrasting four pairs of traditional medicine “contradictions”, it was proposed that the approach choice of the strategic mode of intellectual property rights of traditional medicine should aim at “precision”, “institutionalization” and “internationalization”, and jointly promote it from the three-dimensional perspective of macroscopic pattern “strategic depth, strategic breadth, strategic height”, so as to explore the strategic protection mode of intellectual property rights of traditional medicine with “Chinese characteristics and world level”. © 2022, Editorial department of Chinese Medical Ethics. All rights reserved.

4.
American Journal of Transplantation ; 22(Supplement 3):572, 2022.
Article in English | EMBASE | ID: covidwho-2063393

ABSTRACT

Purpose: To study the clinical application of metagenomic next-generation sequencing (mNGS) in the detection of viral infections in kidney transplant recipients (KTRs) during the COVID-19 pandemic. Method(s): Using mNGS techniques, 50 human fluid samples of KTRs were detected in Henan Province People's Hospital between May 2020 to May 2021, including 20 bronchoalveolar lavage fluid (BALF) samples, 21 urine samples and 9 blood samples. The detected nucleic acid sequences were compared and analyzed with the existing viral nucleic acid sequences in the database, and the virus infection spectrum of KTRs was drawn. Result(s): The viral nucleic acids of 15 types of viruses were detected in 96.00% (48/50) of the samples, of which 11 types of viruses were in BALF (95.00%, 19/20), and the dominant viruses were torque teno virus (TTV) (65.00%;13/20), cytomegalovirus (CMV) (45.00%;9/20) and human alphaherpesvirus 1 (25.00%;5/20). 12 viruses (95.24%, 20/21) were detected in the urine, and the dominant viruses were TTV (52.38%;11/21), JC polyomavirus (52.38%;11/21), BK polyomavirus (42.86%;9/21), CMV (33.33%;7/21) and human betaherpesvirus 6B (28.57%;6/21). 7 viruses were detected in the blood (100.00%, 9/9), and the dominant virus was TTV (100.00%;9/9). Four rare viruses were detected in BALF and urine, including WU polyomavirus, primate bocaparvovirus 1, simian virus 12, and volepox virus. Further analysis showed that TTV infection with high reads indicated a higher risk of acute rejection (P<0.05). Conclusion(s): mNGS detection reveals the rich virus spectrum of infected persons after kidney transplantation, and improves the detection rate of rare viruses. TTV may be a new biomarker for predicting rejection. (Figure Presented).

5.
Journal of Chromatographic Science ; 01:01, 2022.
Article in English | MEDLINE | ID: covidwho-1973113

ABSTRACT

Jinhongtang granule (JHT) is a traditional Chinese medicine formula used for treatment of infection diseases including severe COVID-19. However, pharmacokinetics of JHT was unknown, especially in infection condition. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to simultaneously quantify ten active components form JHT in rat plasma. MS detection was performed by MRM scanning operating in the negative ionization mode. The method showed good linearity (r > 0.997). The accuracy, precision, matrix effect, recovery and stability were all satisfactory with current criterion. The method was successfully applied to compare the pharmacokinetic difference between normal and sepsis rats. The pharmacokinetic behaviors of analytes in sepsis rats were significantly different from those in normal rats. Cmax and AUC of rhein, emodin, aloe emodin, rhein-8-glucoside, aloe emodin 8-glucoside, protocatechuic acid, epicatechin and salidroside, were significantly increased in sepsis rats, except for 4-hydroxycinnamic acid and ferulic acid. In vitro intestinal absorption study using everted intestinal sac preparations indicated that the intestinal permeability was altered under sepsis. In conclusion, pharmacokinetic difference of JHT between normal and sepsis rats were evaluated for the first time, which provided useful information for the clinical application of JHT as an integrative therapy for severe and critical COVID-19.

6.
Chinese Journal of Microbiology and Immunology (China) ; 42(2):141-147, 2022.
Article in Chinese | EMBASE | ID: covidwho-1928711

ABSTRACT

Objective To investigate the changes in epidemiological characteristics of common respiratory pathogens in children in Beijing during COVID-19 epidemic.Methods A total of 9 728 serum samples were collected from cases of acute respiratory infections in Beijing Children′s Hospital from January 2020 to December 2020.Indirect immunofluorescence antibody test was performed to detect IgM antibodies against eight common respiratory pathogens and the test results were statistically analyzed.The eight common respiratory pathogens were influenza virus A (FluA), influenza virus B (FluB), respiratory syncytial virus (RSV), adenovirus (ADV), parainfluenza virus (PIV), Mycoplasma pneumoniae (Mp), Chlamydia pneumoniae (Cp) and Legionella pneumophila (Lp).Results The detection rate of respiratory pathogens in 9 728 cases was 41.71% (4 058/9 728) and respiratory viruses (FluA, FluB, RSV, ADV and PIV) accounted for 46.18% (2 343/5 074) of all detected pathogens.Mp, FluB and FluA accounted for 84.73% (4 299/5 074)of all detected pathogens, and the detection rates were 24.27% (2 361/9 728), 11.49% (1 118/9 728) and 8.43% (820/9 728), respectively.There were 846 cases positive for two kinds of pathogens, and the most common co-infection was Mp and FluB.The detection rates in male and female were 37.56% (2 089/5 562) and 47.26% (1 969/4 166), respectively.There were significant differences in the total detection rate and the positive rates of PIV and Mp between different sexes (P<0.05).The detection rate in school-age children (6-12 years old) was the highest (52.26%, 1 535/2 937).The detection rates of respiratory pathogens in different months ranged from 30.12% (203/674) to 49.81% (268/538) with higher rates in autumn and winter [42.45% (1 304/3 072) and 43.29% (1 618/3 738)].The detection rates of FluA and FluB were higher in summer [11.46% (195/1 701)] and winter [14.63% (547/3738)], respectively.Most of RSV infection occurred in summer [1.35% (23/1 701)], and Mp could be detected all year round, especially in winter and spring [27.21% (1 017/3 738) and 25.64% (312/1 217)].The detection rate of respiratory pathogens in outpatient group was higher than that in inpatient group [46.48% (1 583/3 406) vs 39.15% (2 475/6 322)].The detection rate in severe cases was 26.10% (71/272).The detection rates of total pathogens, FluB and Mp were higher in outpatients than in inpatients and the differences were statistically significant (P<0.05).The detection rates of FluA, PIV and ADV were higher in inpatients than in outpatients and the differences were statistically significant (P < 0.05).The detection rates of total pathogens, FluB and Mp in mild cases were significantly higher than those in severe cases and the differences were statistically significant (P<0.05).The detection rate of RSV in severe cases was significantly higher than that in mild cases and the difference was statistically significant (P<0.05).Conclusions The protective measures taken during the period of regular prevention and control of COVID-19 epidemic could better prevent the spread of respiratory viruses, having a certain impact on the population susceptible to respiratory pathogens and typical seasonal patterns, but had little effect on the prevention and control of Mp.New protective measures needed to be studied to prevent Mp infection in children during epidemical season.

7.
Ieee Journal of Selected Topics in Signal Processing ; 16(2):197-207, 2022.
Article in English | English Web of Science | ID: covidwho-1883130

ABSTRACT

Blood oxygen saturation (SpO(2)) is an important indicator forpulmonary and respiratory functionalities. Clinical findings on COVID-19 show that many patients had dangerously low blood oxygen levels not long before conditions worsened. It is therefore recommended, especially for the vulnerable population, to regularly monitor the blood oxygen level for precaution. Recent works have investigated how ubiquitous smartphone cameras can be used to infer SpO(2). Most of these works are contact-based, requiring users to cover a phone's camera and its nearby light source with a finger to capture reemitted light from the illuminated tissue. Contact-based methods may lead to skin irritation and sanitary concerns, especially during a pandemic. In this paper, we propose a noncontact method for SpO(2) monitoring using hand videos acquired by smartphones. Considering the optical broadband nature of the red (R), green (G), and blue (B) color channels of the smartphone cameras, we exploit all three channels of RGB sensing to distill the SpO(2) information beyond the traditional ratio-of-ratios (RoR) method that uses only two wavelengths. To further facilitate an accurate SpO(2) prediction, we design adaptive narrow bandpass filters based on accurately estimated heart rate to obtain the most cardiac-related AC component for each color channel. Experimental results show that our proposed blood oxygen estimation method can reach a mean absolute error of 1.26% when a pulse oximeter is used as a reference, outperforming the traditional RoR method by 25%.

9.
Modern Pathology ; 35(SUPPL 2):969-970, 2022.
Article in English | EMBASE | ID: covidwho-1857373

ABSTRACT

Background: Since the first case of COVID19 infection in 2019, this RNA virus has led an unprecedented pandemic that infected more than 232 million people. Although the disease is studied extensively, much remains poorly understood. Here, we performed the first correlation study on the peripheral blood morphology and immunophenotype of the white blood cells (WBCs) from COVID19 patients. Design: A total of 52 samples from COVID19 patients and 15 blood samples as control group were analyzed. COVID19 patients were divided into two groups based on clinical severity, severe (respiratory failure) or non-severe (hospitalized but stable). The controls were the patients with negative COVID19 results by PCR and antibody tests. The WBC morphology was examined either by blood smear review or via CellaVision DM analyzer captured images. Navios flow cytometer and Beckman Kaluza C software were used for immunophenotype analysis. Two-tailed T-test was performed on the COVID19 groups and the control group Results: Almost all COVID19 patients showed marked neutrophilia and lymphopenia on the CBC tests. Morphologically, the neutrophils showed irregularities like hypogranulation, toxic granules and pseudo Pelger-Huet anomaly (Fig 1A). In severe COIVD19 group, there was an increase in neutrophils with immatures phenotypes, showing CD33 positivity while CD10, CD13 and CD16 negative (Fig 1B). Conversely, the CD10(+) mature neutrophils aberrantly expressed CD56 (Fig 1B). The percentage of CD56(+) neutrophils was significantly higher in both COVID19 groups, suggesting a stronger cellular adhesion and interaction. The monocytes from the COVID19 patients had increased cytoplasm with cytoplasmic protrusion and vacuolization (Fig 2A). Phenotypically they were positive for CD13, CD33, CD38 and HLA-DR. The lymphocytes were also atypical, including increased cytoplasm with large granules and vacuoles. Phenotypically, they are activated, expressing CD38, HLA-DR, and mainly α/β subtype. Giant platelets with cytoplasmic vacuoles and projections were easily seen. Platelet aggregations were observed (Fig 2B). These platelets were CD45(-) and expressed CD61 at lower-than-normal intensity, while expressing increased CD42b intensity when compared to the control group on a log scale. Conclusions: Despite being a small study, we were able to correlate the morphologic and phenotypic alterations of the WBCs in COVID19 patients. As such, this helped to explain some of the clinical hematologic manifestation of the disease. (Figure Presented).

10.
13th International Conference on E-Education, E-Business, E-Management, and E-Learning, IC4E 2022 ; : 605-610, 2022.
Article in English | Scopus | ID: covidwho-1840637

ABSTRACT

Supply management plays an important role in the business. In our research, we make the introduction with research background in COVID-19, in the APPLE Inc. and large amount of data is constructed. Several methods are used during the task, for example, literature review, data analysis, quantitative analysis and comparative analysis. The research shows the current problems faced by electronic technology companies, which are instability of the supply chains, material shortage and regional policies, after which the research reasons for deep causes and provides feasible improvements of the company, which are production concentration, purchase limit strategy, online commodity physical models, price reduction, and comprehensive capital. © 2022 ACM.

11.
Modern Pathology ; 35(SUPPL 2):969-970, 2022.
Article in English | Web of Science | ID: covidwho-1782022
12.
Information Discovery and Delivery ; 49(3):189-192, 2021.
Article in English | Web of Science | ID: covidwho-1691708
13.
Chinese Journal of New Drugs ; 31(1):69-76, 2022.
Article in Chinese | Scopus | ID: covidwho-1661512

ABSTRACT

As of May 2021, 6 new vaccines against coronavirus disease 2019 (COVID-19) have been conditionally approved and urgently used in China, including products of 4 new inactivated vaccines, 1 new adenovirus vaccine and 1 new recombinant vaccine. All the six vaccine products have been under different stages of clinical trials in global scale, and the results of the clinical trials have demonstrated the safety of the vaccines and the efficacy against COVID-19. Focusing on the above products, this paper deeply summarizes the characteristics of different new vaccine products and the clinical trial results as the key evidence supporting the approval of the products. In addition, facing the current severe situation of COVID-19, the status and challenges regarding the research and development of new vaccines and therapeutics are analyzed. © 2022, Chinese Journal of New Drugs Co. Ltd. All right reserved.

14.
Journal of Materials Chemistry C ; : 9, 2022.
Article in English | Web of Science | ID: covidwho-1655684

ABSTRACT

The typical mode of interaction between humans and machines in current intelligent equipment and personalized health care systems is mainly contact-type. However, there are severe problems associated with direct contact, such as uncomfortable wear and cross-infection of bacteria or viruses, especially under global pandemic conditions (e.g., COVID-19, MERS-CoV). In this study, a flexible humidity sensor is developed based on alkalized MXenes and polydopamine (PDA). The unique accordion-like hierarchical structure of the alkalized MXenes with large specific surface area and the chemical structure of the abundant water-absorbing functional groups of PDA wrapped on the MXene surface contribute synergistically to the outstanding performance of the sensor, which has high sensitivity, rapid response, and large detection range. The device was successfully used to control a noncontact switch system based on the distance of the fingertip and monitor different breathing patterns of a volunteer from a long range, proving its potential application in future noncontact human-machine interaction and human physiology monitoring.

15.
IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) ; : 4240-4244, 2021.
Article in English | Web of Science | ID: covidwho-1532675

ABSTRACT

The existing face recognition datasets usually lack occlusion samples, which hinders the development of face recognition. Especially during the COVID-19 coronavirus epidemic, wearing a mask has become an effective means of preventing the virus spread. Traditional CNN-based face recognition models trained on existing datasets are almost ineffective for heavy occlusion. To this end, we pioneer a simulated occlusion face recognition dataset. In particular, we first collect a variety of glasses and masks as occlusion, and randomly combine the occlusion attributes (occlusion objects, textures,and colors) to achieve a large number of more realistic occlusion types. We then cover them in the proper position of the face image with the normal occlusion habit. Furthermore, we reasonably combine original normal face images and occluded face images to form our final dataset, termed as Webface-OCC. It covers 804,704 face images of 10,575 subjects, with diverse occlusion types to ensure its diversity and stability. Extensive experiments on public datasets show that the ArcFace retrained by our dataset significantly outperforms the state-of-the-arts. Webface-OCC is available at https://github.com/Baojin-Huang/Webface-OCC.

16.
Acta Optica Sinica ; 41(10):10, 2021.
Article in Chinese | Web of Science | ID: covidwho-1374562

ABSTRACT

For NOx, pollutions in Wuhan during the outbreak of COVID-19, we applied a mobile MAX-DOAS and a portable ultraviolet DOAS to cooperatively measure NOx, concentration in the third ring road of Wuhan from Feb. 29th to Mar. 14th, 2020. The mobile MAX-DOAS acquired the vertical column concentration (VCD) distribution of NO2 along its course and the portable ultraviolet DOAS measured the NO and NO2 concentrations to calculate [NOx]/[NO2]. Then, the NOx emission flux and its error of the third ring road of Wuhan were calculated in conjunction with the data of the wind field. The results show that the NO, emission flux during the measurements in the third ring of Wuhan ranges from 7.78 mol/s to 15.71 mol/s, about 10.78 mol/s on average. Compared with the average [NOx]/[NO2], the real-time [NOx]/[NO2] along the route of the mobile MAX-DOAS derived from the portable ultraviolet DOAS could effectively reduce the error of NOx emission flux caused by the [NOx,]/[NO2] error. However, this method is not recommended in scenarios with substantial near-surface NOx emission sources.

17.
Sustainability (Switzerland) ; 13(14), 2021.
Article in English | Scopus | ID: covidwho-1329177

ABSTRACT

Due to the outbreak of COVID-19, many people have to accept remote working. However, as COVID-19 has been effectively controlled in China, remote office services provided by enterprise social networks (ESNs) is no longer a necessary choice of users. There has not yet been any referen-tial research for ESN enterprises concerning how to encourage users willing to use ESNs continu-ously. Therefore, the purpose of this research is to identify the critical factors of ESN continuous usage intention to make up the research gap of ESN continuous usage intention and to help enterprises address the issue of sustained growth. This research combines elements of the task technology fit (TTF) model and D&M information systems success (ISS) model, explaining the continuous usage intention of ESN users. The empirical analysis results are based on the sample data of 668 Chinese respondents with experience in ESNs use and analyzed using structural equation modeling (SEM). Results show that task technology fit, performance expectancy and the satisfaction degree have a significant influence on continuous usage intention of ESNs. The research findings can provide the theoretical basis for sustained development and follow-up research of the ESN industry. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

18.
Aerosol and Air Quality Research ; 21(7):20, 2021.
Article in English | Web of Science | ID: covidwho-1314848

ABSTRACT

This study mainly involved conducting an atmospheric sensitivity analysis of the dry deposition and PM2.5-bound content of total PCDD/Fs-WHO2005-TEQ, respectively. The results for Fuzhou and Xiamen cities showed that the total PCDD/F mass concentration was the factor most positively correlated to the dry deposition flux: When Delta P/P ranged from -50% to 0%, Delta S/S ranged from -66.0% to 0%, but when Delta P/P increased from 0% to +50%, Delta S/S increased from 0% to +66.0%, respectively. The second factor positively correlated with the deposition flux was the PM2.5 concentration: When Delta P/P ranged from -50% to 0%, Delta S/S ranged from -63.3% to 0%;when Delta P/P increased from 0% to +50% and +100%, Delta S/S ranged from 0% to +20.8 and -0.9%, respectively. Ambient air temperature was found to be less sensitive to dry deposition fluxes in total PCDD/Fs-WHO2005-TEQ: When Delta P/P ranged from -50% to -17% and 0%, Delta S/S ranged from -17.0% to +5.6% and 0%;when Delta P/P increased from 0% to +50%, Delta S/S increased from 0% to -84.5%, respectively. The sensitivity analysis for PM2.5-bound total PCDD/Fs-WHO2005-TEQ content had similar results to those for dry deposition flux. In addition, in 2018, 2019, and 2020, the annual average PM2.5-bound total PCDD/Fs-WHO2005-TEQ content at Fuzhou and Xiamen was 0.430, 0.127, 0.303, and 0.426 ng-WHO2005-TEQ g(-1) in the spring, summer, autumn and winter, respectively, which showed that summer had the lowest content, while spring and winter had the highest. The results of this study provided useful information for gaining a deeper understanding of both dry deposition and particle-bound of PCDD/Fs in the ambient air.

19.
Journal of Theoretical and Applied Electronic Commerce Research ; 16(5):1537-1556, 2021.
Article in English | Scopus | ID: covidwho-1264487

ABSTRACT

With the acceleration of global economic integration and digital economy, cross-border mobile payment has gained growing attention. On the other hand, as COVID-19 keeps on spreading, the popularization of cross-border mobile payment can lower the risk of infection caused by cash payment of tourists. However, though previous researchers already examined mobile payment users’ behavioral intention from different perspectives, these research findings tend to concentrate on the non-cross-border section of mobile payment. Therefore, the purpose of this research is to examine factors influencing cross-border mobile payment use intention from the user perspective, and combining three theoretical models, chiefly UTAUT2 (extended unified theory of acceptance and use of technology), ITM (initial trust model), and TTF (task technology fit). In this research, 786 Chinese with the experience of using cross-border mobile payment while traveling to South Korea are adopted as respondents, and the structural equation model is used to empirically analyze the data of these research samples. The study found that initial trust, performance expectancy, effort expectancy, facilitating conditions, price value, task technology fit, and initial trust have significant effects on use intention. Research findings of this paper can deepen people’s understanding of users’ intention to use cross-border mobile payment, and provide theoretical support for the development of cross-border mobile payment. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

20.
Aerosol and Air Quality Research ; 21(5), 2021.
Article in English | Scopus | ID: covidwho-1234872

ABSTRACT

In this study, the atmospheric total-PCDD/Fs-WHO2005-TEQ concentrations, gas-particle partitioning, PM2.5 concentration, PM2.5-bound total PCDD/Fs-WHO2005-TEQ content and dry deposition flux in Shanghai and Nanjing were investigated from 2018-2020. In Shanghai, the total PCDD/Fs-WHO2005-TEQ concentration dropped from 0.0291 pg-WHO2005-TEQ m–3 from 2018–2019 to 0.0250 pg-WHO2005-TEQ m–3 in 2020, while in Nanjing, it dropped from 0.0423 pg-WHO2005-TEQ m–3 to 0.0338 pg-WHO2005-TEQ m–3. The average concentrations of PCDD/Fs-WHO2005-TEQ in spring and winter in Shanghai and Nanjing were 47.6% and 53.8% higher than those in summer, respectively. From 2018-2019, the average particle phase fractions of total-PCDD/Fs-WHO2005-TEQ in Shanghai and Nanjing were 50.3% and 57.5%, respectively, while in 2020, they were 47.8% and 55.1%, respectively. From 2018-2019, the average PM2.5-bound total PCDD/Fs-WHO2005-TEQ content was 0.342 and 0.493 ng-WHO2005-TEQ g–1 in Shanghai and Nanjing, respectively, while in 2020, it was 0.312 and 0.489 ng-WHO2005-TEQ g–1, respectively. In Shanghai and Nanjing, the average PM2.5-bound total PCDD/Fs-WHO2005-TEQ content in spring and winter was 77.5% and 73.2% higher than that in summer, respectively. From 2018–2019, the dry deposition flux of total-PCDD/Fs-WHO2005-TEQ was 316.3 and 460.5 pg WHO2005-TEQ m–2 month–1 in Shanghai and Nanjing, respectively, while in 2020, it was 272.5 and 368.4 pg WHO2005-TEQ m–2 month–1, respectively. The average dry deposition flux of total-PCDD/Fs-WHO2005-TEQ in spring and winter was 47.6% and 53.8% higher than that summer in Shanghai and Nanjing, respectively. The above results indicate that COVID-19 in 2020 had a positive effect on air quality improvement in PCDD/Fs. On average, more than 98.88% of the total PCDD/Fs-WHO2005-TEQ dry deposition flux was primarily contributed by the particle phase. This was attributed to the fact that dry deposition of particle phase PCDD/Fs was mainly due to gravitational settling accompanied by higher dry deposition velocities, while the gas phase PCDD/Fs were deposited mostly by diffusion at a lower dry deposition velocity. © The Author(s).

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