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1.
1st International Meeting for Applied Geoscience and Energy ; 2021-September:3209-3214, 2021.
Article in English | Scopus | ID: covidwho-1595346

ABSTRACT

Urban activities in megacities around the world are not only the most severely impacted by the COVID-19 pandemic, but also the most consequential for the effectiveness of the mitigation measures. Therefore, monitoring and understanding the realtime changes of different sectors of an urban society is vital for policy making and dynamic pandemic management. By analyzing the high-frequency seismic signals, we separate the motor vehicle signal and the runner signal from the environment and background noise. We quantify the impact of the pandemic and its corresponding mitigation measures as traffic flow at nonessential workplaces, essential workplaces, and recreational areas. Enabled by the anonymity of seismic data, our study achieves an unprecedented spatial and temporal resolution that is pivotal to understand the heterogeneity and evolution of pandemic responses in different sectors of an urban society. The rich seismic-derived information provide a unique opportunity for realtime urban activity monitoring and dynamic policy making to ensure a successful pandemic mitigation while minimizing negative impacts on urban lifestyle. © 2021 Society of Exploration Geophysicists First International Meeting for Applied Geoscience & Energy

2.
Sustainability (Switzerland) ; 13(24), 2021.
Article in English | Scopus | ID: covidwho-1593800

ABSTRACT

Quantified components of the global food system are used to assess long-term global food security under a series of socio-economic, epidemic normalization and climate change scenarios. Here, we evaluate the global food security including the global farming system as well as the global food trade, reserve and loss systems from 1961 to 2019, and analyze their temporal and spatial characteristics by using the global food vulnerability (GFV) model. The spatio–temporal patterns of the vulnerability of the global food system were consistent with the GFSI. As food production and consumption vary greatly in different countries which have continued for a long time, food exports from many developed agricultural countries have compensated for food shortages in most countries (about 120 net grain-importing countries). As a result, many countries have relied heavily on food imports to maintain their domestic food supplies, ultimately causing the global food trade stability to have an increasing impact on the food security of most countries. The impact of global food trade on global food security increased from 9% to 17% during 1961–2019, which has increased the vulnerability of the global food system. The food damage in the United States, Russia, China, and India has varied significantly, and global cereal stocks have fluctuated even more since 2000. From 1961 to 2019, the food system security of some Nordic countries significantly improved, while the food system security of most African countries significantly deteriorated. Most countries with high food insecurity are located in Africa and South Asia. In order to cope with extreme events, these countries need to strengthen and improve their own food production and storage systems, which will help the World Food and Agriculture Organization to formulate relevant food policies and maintain sustainable development. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

3.
Seismological Research Letters ; 93(1):181-192, 2022.
Article in English | Web of Science | ID: covidwho-1581612

ABSTRACT

Human foot traffic in urban environments provides essential information for city planners to manage the urban resources and urban residents to plan their activities. Compared to camera or mobile-based solutions, seismic sensors detect human footstep signals with fewer privacy concerns. However, seismic sensors often record signals generated from multiple sources, particularly in an urban outdoor environment. In this article, we monitor people's running activities during COVID-19 pandemic with a seismic sensor in a park in Singapore. We compare the spectra of natural and urban events in the recorded seismic data. For each 3 s seismic data, we define hierarchical screening criteria to identify footsteps based on the spectrum of the signal and its envelope. We derive the cadence of each runner by detecting the primary frequency of the footstep signals. The resulting algorithm achieves higher accuracy and higher temporal resolution for weak and overlapping signals compared to existing methods. Runner statistics based on four-month long seismic data show that urban running activities have clear daily and weekly cycles. Lockdown measures to mitigate COVID-19 pandemic promoted running activities, particularly over the weekends. Cadence statistics show that morning runners have higher cadence on average.

4.
Journal of Forecasting ; 2021.
Article in English | Scopus | ID: covidwho-1576019

ABSTRACT

We propose a procedure that jointly estimates expectation, uncertainty, and disagreement using a flexible hierarchical ordered response model and individual-level qualitative data. Based on the Michigan survey of US consumers, our results reveal how their inflation expectations and the associated uncertainty are affected by various factors, including their perceptions of economic conditions, recollections of relevant news reports, and sociodemographic characteristics. An examination of the dynamics of inflation uncertainty and disagreement produces evidence in support of using the latter as a proxy of the former. However, our results also highlight important episodes (such as the start of the COVID pandemic) in which the two series diverge. © 2021 John Wiley & Sons, Ltd.

5.
Acta Medica Mediterranea ; 37(6):3297-3302, 2021.
Article in English | Scopus | ID: covidwho-1566893

ABSTRACT

Objective: The aim of this study was to elucidate the association of COVID-19 prognosis with the indexes of inflammation and coagulation. Methods: The clinical data of 103 cases of COVID-19 were retrospectively analyzed. COX regression models and 95% confidence intervals (CIs) were applied to estimate the COVID-19 prognosis. Results: The results showed that C-reactive protein (HR=1.007, p<0.001), procalcitonin (HR=1.013, p=0.006), prothrombin time (HR=1.190, p<0.001), Fibrinogen (HR=0.784, p=0.002) and D-dimer (HR=1.078, p<0.001) is associated with an increased risk of COVID-19 death. Among the inflammation indicators, the maximum area under the ROC curve of NLR is 0.87. In the coagulation index, the maximum area under the ROC curve of PT is 0.84. For the combined indicators of inflammation and coagulation, the area under the ROC curve is 0.89. Conclusions: In conclusion, we found that the length of PT at admission and the level of fibrinogen and D-dimer were related to the risk of COVID-19 death. It may be considered to jointly predict the risk of death of COVID-19 with inflammation and coagulation indicators. © 2021 A. CARBONE Editore. All rights reserved.

6.
Chinese Journal of Disease Control and Prevention ; 25(4):445-453, 2021.
Article in Chinese | Scopus | ID: covidwho-1566860

ABSTRACT

Objective To determine the differences in the epidemiological characteristics of asymptomatic patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and coronavirus disease 2019 (COVID-19) patients. Methods The relevant data of asymptomatic SARS-CoV-2 transmission literature in PubMed, Web of Science, CNKI, VIP medicine and Wanfang medical database were extracted as of August 1, 2020. Epidemiological information was screened and extracted according to pre-established inclusion and exclusion criteria. Age, gender, virus shedding duration and virual load of asymptomatic carriers were summarized and analyzed. Results A total of 38 articles met the criteria, 17 of which were asymptomatic case reports related to the virus shedding duration. Compared with symptomatic infected persons, asymptomatic individuals were younger [Weighted Mean Difference (WMD), WMD=-5.27, 95% CI: -9.78--0.76, P < 0.001] and the viral load was lower (WMD=2.36, 95% CI: 0.65-4.07, P=0.007). The virus shedding duration of asymptomatic individuals (median=11 days) was shorter than symptomatic patients (median=16 days). Conclusion Asymptomatic individuals with SARS-CoV-2 were younger, had a lower viral load and a shorter virus shedding duration than COVID-19 patients. © 2021, Publication Centre of Anhui Medical University. All rights reserved.

7.
Chinese Pharmaceutical Journal ; 56(20):1690-1693, 2021.
Article in Chinese | Scopus | ID: covidwho-1566820

ABSTRACT

OBJECTIVE: To study the dose-based BCS (biopharmaceutical classification system) classification of dexamethasone for different indications. METHODS: Saturation shake-flask method was utilized with the conditions of shaking water bath at 37℃ and 120 r•min-1, somewhat excess solids added into saturate systems at pH 1.2, 4.5 and 6.8 buffers respectively. And high-performance liquid chromatography was used for saturation concentration measurement. In this study, the dosages of dexamethasone for both classic and new indications were collected, such as covid-19, which were divided into low-dose, intermediate-dose and high-dose. Then the dissolution volumes (DSVs) were calculated and the indication-based BCS classifications of dexamethasone was studied. RESULTS: At the low-dose, the BCS classification of dexamethasone was high solubility;at the high-dose, the BCS classification of dexamethasone was low;and at the intermediate-dose, the BCS classification of dexamethasone was on the edge of low solubility and high solubility. CONCLUSION: This study provides basic data for the BCS classification of dexamethasone;dose-related solubility classification has guiding significance for the BCS classification of dexamethasone for new indications, and provides refine reference for the rationality of the BE wavier for solid oral dosage forms in the consistency evaluation of generic drugs. Copyright 2021 by the Chinese Pharmaceutical Association.

8.
Ieee Transactions on Instrumentation and Measurement ; 70:12, 2021.
Article in English | Web of Science | ID: covidwho-1550771

ABSTRACT

In the era of Corona Virus Disease 2019 (COVID-19), wearing a mask can effectively protect people from infection risk and largely decrease the spread in public places, such as hospitals and airports. This brings a demand for the monitoring instruments that are required to detect people who are wearing masks. However, this is not the objective of existing face detection algorithms. In this article, we propose a two-stage approach to detect wearing masks using hybrid machine learning techniques. The first stage is designed to detect candidate wearing mask regions as many as possible, which is based on the transfer model of Faster_RCNN and InceptionV2 structure, while the second stage is designed to verify the real facial masks using a broad learning system. It is implemented by training a two-class model. Moreover, this article proposes a data set for wearing mask detection (WMD) that includes 7804 realistic images. The data set has 26403 wearing masks and covers multiple scenes, which is available at "https://github.com /BingshuCV/WMD." Experiments conducted on the data set demonstrate that the proposed approach achieves an overall accuracy of 97.32% for simple scene and an overall accuracy of 91.13% for the complex scene, outperforming the compared methods.

9.
Discrete and Continuous Dynamical Systems-Series B ; 0(0):21, 2021.
Article in English | Web of Science | ID: covidwho-1542857

ABSTRACT

In this paper, we use delay differential equations to propose a mathematical model for COVID-19 therapy with both defective interfering particles and artificial antibodies. For this model, the basic reproduction number R-0 is given and its threshold properties are discussed. When R-0 < 1, the disease-free equilibrium E-0 is globally asymptotically stable. When R-0 > 1, E-0 becomes unstable and the infectious equilibrium without defective interfering particles E-1 comes into existence. There exists a positive constant R-1 such that E-1 is globally asymptotically stable when R-1 < 1 < R-0. Further, when R-1 > 1, E-1 loses its stability and infectious equilibrium with defective interfering particles E-2 occurs. There exists a constant R-2 such that E-2 is asymptotically stable without time delay if 1 < R-1 < R-0 < R-2 and it loses its stability via Hopf bifurcation as the time delay increases. Numerical simulation is also presented to demonstrate the applicability of the theoretical predictions.

10.
Preprint in English | PUBMED | ID: ppcovidwho-293119

ABSTRACT

Pathogenic coronaviruses represent a major threat to global public health. Here, using a recombinant reporter virus-based compound screening approach, we identified several small-molecule inhibitors that potently block the replication of the newly emerged severe acute respiratory syndrome virus 2 (SARS-CoV-2). Among them, JIB-04 inhibited SARS-CoV-2 replication in Vero E6 cells with an EC50 of 695 nM, with a specificity index of greater than 1,000. JIB-04 showed in vitro antiviral activity in multiple cell types against several DNA and RNA viruses, including porcine coronavirus transmissible gastroenteritis virus. In an in vivo porcine model of coronavirus infection, administration of JIB-04 reduced virus infection and associated tissue pathology, which resulted in improved weight gain and survival. These results highlight the potential utility of JIB-04 as an antiviral agent against SARS-CoV-2 and other viral pathogens.

11.
Medical Journal of Peking Union Medical College Hospital ; 12(1):38-43, 2021.
Article in Chinese | Scopus | ID: covidwho-1513197

ABSTRACT

Objective To explore the application value of Biofire Filmarry pneumonia panel (PN) in detection of secondary and concomitant pathogen among critically ill patients with coronavirus disease 2019(COVID-19). Methods We consecutively included and analyzed the clinical data of critically ill patients with COVID-19 transferred to the ICU from February to April 2020 in the Sino-French Campus of Wuhan Tongji Hospital. Samples of Bronchoalveolar lavage fluid obtained by bedside bronchoscopy were sent for Biofire Filmarray PN and standard culture concomitantly. We compared the results of two methods and evaluated their concordance. Results In total, 21 critically ill patients with COVID-19 were included and 54 samples were tested, including 33 (61.1%) Biofire Filmarray PN tests (21 patients) and 21 (38.9%) standard cultures (14 patients), in which 19 pairs (38 samples) underwent both tests simultaneously. In Biofire Filmarray PN group, the turnaround time was about 1 hour. There were 74 positive results in 32 samples (97.0%) from 20 patients, including 29 cases(39.2%) of Acinetobacter baumannii complex, 21 cases (28.4%) of Pseudomonas aeruginosa, 16 cases (21.6%)of Klebsiella pneumoniae, 5 cases (6.8%) of Escherichia coli, 1 case (1.4%)each of Enterobacter cloacae, Haemophilus influenzae, and respiratory syncytial virus. In the standard culture group, the turnaround time was about 3 days. 19 positive results returned in 16 (76.2%) samples from 11 patients, including 8 cases (42.1%) of Pseudomonas aeruginosa, 6 cases (31.6%) of Acinetobacter baumannii, 4 cases (21.1%) of Stenotrophomonas malt and 1 case (5.3%) of Myxobacterium. Among the 19 pairs of “back-to-back” specimens, 15 pairs were concordant, and the agreement ratio was 78.9%. Conclusions Acinetobacter baumannii and Pseudomonas aeruginosa may be the common pathogens of secondary or concomitant infection in critically ill patients with COVID-19. Biofire Filmarray PN is a rapid diagnostic test and has application value in such patients;its sensitivity and accuracy require further investigation with larger sample sizes. © 2021, Peking Union Medical College Hospital. All rights reserved.

12.
8th ACM SIGCHI Annual Symposium on Computer-Human Interaction in Play, CHI PLAY 2021 ; : 371-375, 2021.
Article in English | Scopus | ID: covidwho-1511513

ABSTRACT

Dino-Store is a persuasive game that was designed to use gamification way to communicate with people and raise awareness on COVID-19. The game's setting is grocery shopping and the mechanic indicates that how different protection strategies, such as wearing mask, keeping social distance can affect people's infection chances in the COVID-19 pandemic. This paper will break down how the game designed by merging concepts from persuasive game models and uncomfortable interaction theory to create an engaging, but stressful experience for the user. © 2021 Owner/Author.

13.
2nd International Conference on Computer Vision, Image, and Deep Learning ; 11911, 2021.
Article in English | Scopus | ID: covidwho-1511403

ABSTRACT

Object detection is a hot talking point in computer vision. Recently, as COVID-19 is spreading globally, the epidemic prevention and control has entered a normalization, wearing masks when entering and leaving public places and taking public transportation has now become normalized. The recognition of face mask is also of increasing concern. Then fast and accurate mask identification is essential. The Faster R-CNN is currently a more advanced object detection algorithm. It has the advantages of fast detection speed and high detection accuracy and is widely used in various fields. However, this method often fails to demonstrate its excellent performance in detecting small objects. This paper is based on the Faster R-CNN object detection algorithm and introduces FPN to solve multi-scale mask recognition and detection. The feature map of each resolution is introduced into the latter resolution feature map for element-wise summation operation. Fusing shallow layers with high resolution and deep layers with rich semantic information to improve the ability to detect small objects. The method is validated with 2000 face mask images as the dataset. Experimentally, the improved method proposed in this paper proves to be effective and better than the original algorithm. © 2021 SPIE.

14.
21st International Conference on Solid-State Sensors, Actuators and Microsystems (Transducers) ; : 743-746, 2021.
Article in English | Web of Science | ID: covidwho-1501345

ABSTRACT

Serological tests play important roles in the fight against the Coronavirus Disease 2019 (COVID-19). The most commonly used methods, enzyme-linked immunosorbent assays (ELISA), provide reliable and sensitive antibody measurement though they require bulky laboratory infrastructure as well as lengthy turnaround time. Conversely, lateral flow immunoassays (LFIA) are suitable for rapid point-of-care tests but with limited sensitivity. To combine the best attributes of ELISA and LFIA, we developed a novel streamlined immuno-PCR assay and applied it to a portable magnetofluidic instrument for point-of-care serological tests. In testing 107 clinical samples, our point-of-care serological test showed 98.3% (58/59) specificity and 93.8% (45/48) agreement with benchtop immunoassays. Moreover, 100% agreement was achieved by only slightly increasing the total assay time to 45 min, demonstrating its potential as a new point-of-care serological test for COVID-19 and beyond.

15.
18th International Conference on Scientometrics and Informetrics (ISSI) ; : 1511-1512, 2021.
Article in English | Web of Science | ID: covidwho-1498760
16.
Frontiers in Environmental Science ; 9:8, 2021.
Article in English | Web of Science | ID: covidwho-1497069

ABSTRACT

At the beginning of 2020, broke out. Because the virus is extremely contagious and the mortality rate after infection is extremely high, China and many countries in the world have imposed lockdowns. Air pollutants during the epidemic period have attracted the attention of many scholars. This research is to use predictive models to describe changes in extreme air pollutants. China is the first country in the world to enter the lockdown state. This study uses data from 2015-2020 to compare and predict the concentration of extreme pollutants before and after the lockdown. The results show that the lockdown of the epidemic will reduce the annual average concentration of PM2.5, and the annual average concentration of O-3 will increase first and then decrease. Through analysis, it is concluded that there is a synergistic decrease trend between PM2.5 and O-3. With the various blockade measures for epidemic prevention and control, the reduction of extreme air pollutant concentrations is sustainable. The assessment of China's air quality in conjunction with the can provide scientific guidance for the Chinese government and other relevant departments to formulate policies.</p>

17.
Journal of Applied Analysis and Computation ; 11(5):2611-2629, 2021.
Article in English | Scopus | ID: covidwho-1481207

ABSTRACT

In this paper, we use ordinary differential equations to propose a mathematical model for COVID-19 therapy with both defective interfering particles and artificial antibodies. For this model, the basic reproduction number R0 is given and its threshold properties are discussed. We investigate the global asymptotic stability of disease-free equilibrium E0 and infection equilibrium without defective interfering particles E1 by utilizing Lyapunov function and LaSalle’s invariance principle. For infection equilibrium with defective interfering particles E2, stability and Hopf bifurcation results are presented. Numerical simulation is also given to demonstrate the applicability of the the-oretical predictions. © 2021, Wilmington Scientific Publisher. All rights reserved.

18.
Chinese Journal of New Drugs ; 30(19):1787-1793, 2021.
Article in Chinese | EMBASE | ID: covidwho-1473136

ABSTRACT

Objective: To develop a sandwich ELISA method for detection of N protein in SARS-CoV-2 inactivated vaccine, and to further validate and primarily apply it for N protein qutification. Methods: The indirect ELISA method was used to assess the affinity of different anti-N protein antibodies by coating the recombinant N protein. Then the sandwich ELISA system was set up by using antibodies rN003 and rN002 as the capture and detection antibody, respectively. Also, the method for fully lysing virus to release all the N protein was confirmed. Validation of linear range, accuracy, precision, intermediate precision, specificity and LLD were obtained, and N protein content in 6 batches of SARS-CoV-2 inactivated vaccine was determined using this method. Results: N protein content has good linearty within the concentration range of 0.018~0.75 μg•mL-1 (R2>0.98), with the recovery of 80%~120% and CV <10%. N protein concentrations for 6 batches of samples accounted for 10%~20% of the total protein. All samples showed a good uniformity. Conclusions: The sandwich ELISA method for detection of N protein in SARS-CoV-2 inactivated vaccine was successfully developed with good linearty, accuracy, precision, intermediate precision, selectivity, and sensitivity, which can satisfy the N protein detection of SARS-CoV-2 inactivated vaccine.

19.
Br J Surg ; 108(9): e319, 2021 Sep 27.
Article in English | MEDLINE | ID: covidwho-1475776
20.
Gut ; 70(SUPPL 2):A13, 2021.
Article in English | EMBASE | ID: covidwho-1467716

ABSTRACT

Background SARS-CoV-2 has caused the COVID-19 pandemic, 14-53% with COVID-19 developed hepatic dysfunction. More data is required to ascertain the pattern of liver injury in patients with COVID-19. Here we report the use of human liver and biliary organoids as a tool to investigate the SARSCoV- 2 infection and virus-induced tissue damage ex vivo at the cellular and molecular levels. Methods Immunofluorescence staining and RT-qPCR was performed to examine the susceptibility and replication of human liver and biliary organoids to SARS-CoV-2. Transmission electron microscopy was performed to investigate the ultrastructure of SARS-CoV-2 infected biliary organoid. The mRNA sequence analysis was performed to determine gene expression changes induced by SARS-CoV-2-infection of biliary organoids. Results Immunofluorescence staining showed that SARS-CoV-2 spike (S) glycoprotein protein was readily detected in patchy areas of the human liver and biliary organoids, whereas no signal was found in uninfected control. RT-qPCR showed that the SARS-CoV-2 genomic RNAs revealed a dramatic increase of viral load in organoids at 24 h post-infection (MOI=1) and it can remain stable 96 hours in the liver organoids and 48 hours in biliary organoids. Unsupervised transmission electron microscopy (TEM) showed that viral particles occurred in the lumen of the organoid, at the basolateral and apical side of the organoid, even in membrane-bound vesicles. Additionally, RNA-seq revealed early cell response to virus infection, including the well-known upregulation of chemokines and inflammatory cytokines. Conclusions Therefore, the hepatocytes and bile duct cells have effectively been infected by COVID-19, and human liver and biliary organoids can serve as a pathophysiological model to investigate the underlying mechanism of SARS-CoV-2 infection.

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