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1.
6th International Conference on Transportation Information and Safety, ICTIS 2021 ; : 1443-1447, 2021.
Article in English | Scopus | ID: covidwho-1948786

ABSTRACT

Carbon emission is largely reduced during the COVID-19 due to the lockdown. However, the accurate impact in the personal transport sector after the epidemic is still not clear. To accurately measure the travel pattern variation effects on utility factor of plug-in hybrid electric vehicles (PHEV s) due to COVID-19, travel pattern, charging pattern, and utility factors (UF) are compared in a typical city based on actual travel data before and after the pandemic. The result shows that the number of trips and the daily vehicle kilometers travelled decreased significantly during the pandemic while the average daily travel mileage increased quickly after the pandemic and is only 9% lower than that before the pandemic. Some consumers even travel longer with personal vehicles to avoid possible health risks from public transportation. The electricity utility factor after the pandemic is 0.022 larger compared to that before the pandemic due to the variation of travel patterns, a 60-km-range PHEV has a pre-pandemic standard UF of 0.745 and a post-pandemic standard UF of 0.767. Besides, the actual UF is 15% smaller compared to the standard UF due to the actual charging frequency in reality. © 2021 IEEE.

2.
Embase; 2022.
Preprint in English | EMBASE | ID: ppcovidwho-334805

ABSTRACT

Omicron sub-lineage BA.2 has rapidly surged globally, accounting for over 60% of recent SARS-CoV-2 infections. Newly acquired RBD mutations and high transmission advantage over BA.1 urge the investigation of BA.2's immune evasion capability. Here, we show that BA.2 causes strong neutralization resistance, comparable to BA.1, in vaccinated individuals' plasma. However, BA.2 displays more severe antibody evasion in BA.1 convalescents, and most prominently, in vaccinated SARS convalescents' plasma, suggesting a substantial antigenicity difference between BA.2 and BA.1. To specify, we determined the escaping mutation profiles1,2 of 714 SARS-CoV-2 RBD neutralizing antibodies, including 241 broad sarbecovirus neutralizing antibodies isolated from SARS convalescents, and measured their neutralization efficacy against BA.1, BA.1.1, BA.2. Importantly, BA.2 specifically induces large-scale escape of BA.1/BA.1.1effective broad sarbecovirus neutralizing antibodies via novel mutations T376A, D405N, and R408S. These sites were highly conserved across sarbecoviruses, suggesting that Omicron BA.2 arose from immune pressure selection instead of zoonotic spillover. Moreover, BA.2 reduces the efficacy of S309 (Sotrovimab)3,4 and broad sarbecovirus neutralizing antibodies targeting the similar epitope region, including BD55-5840. Structural comparisons of BD55-5840 in complexes with BA.1 and BA.2 spike suggest that BA.2 could hinder antibody binding through S371F-induced N343-glycan displacement. Intriguingly, the absence of G446S mutation in BA.2 enabled a proportion of 440-449 linear epitope targeting antibodies to retain neutralizing efficacy, including COV2-2130 (Cilgavimab)5. Together, we showed that BA.2 exhibits distinct antigenicity compared to BA.1 and provided a comprehensive profile of SARS-CoV-2 antibody escaping mutations. Our study offers critical insights into the humoral immune evading mechanism of current and future variants.

3.
Open Forum Infectious Diseases ; 8(SUPPL 1):S361, 2021.
Article in English | EMBASE | ID: covidwho-1746477

ABSTRACT

Background. BRII-196 and BRII-198 are human monoclonal antibodies (mAb) with an extended half-life targeting distinct epitopes of the spike protein on SARSCoV-2. Mutations in these epitope regions are continuously emerging, potentially conferring resistance to COVID-19 therapeutics in development. Individual phase I studies showed that BRII-196 or BRII-198 alone were safe and well tolerated in healthy subjects. The BRII-196 and BRII-198 cocktail is currently under evaluation in Phase 2/3 studies for the treatment of COVID-19. Methods. Preclinical study: BRII-196 and BRII-198 were evaluated in the microneutralization assay using pseudo-viruses encoding mutations identified in the spike protein of a panel of SARS-CoV-2 variants of concerns, including strains originating in UK, SA, BR, CA, and India. The fold-change in neutralization IC50 titers relative to wild-type virus was calculated. Phase 1 study: healthy adults received sequential IV BRII-196 and BRII-198 (n=9) or placebo (n=3);and were followed for 180 days. Two dose levels (750mg/750mg and 1500mg/1500mg) were evaluated for safety, pharmacokinetics and immunogenicity. Interim analysis results are presented. Results. Preclinical: BRII-196 and BRII-198 exhibited neutralizing activity against pseudo-virus variants that contained spike mutations of a panel of variants including B.1.1.7 (UK), B.1.351(SA), P.1(BR), B.1.427/429 (CA), B.1.526 (NY), and B.1.617 (IN), comparable to that against wild-type virus. Phase I study: BRII-196 plus BRII-198 was well tolerated with no dose-limiting adverse events (AEs), deaths, serious adverse events, or infusion reactions. The majority of AEs were isolated asymptomatic grade 1-2 laboratory abnormalities. (Table 1). Each mAb displayed pharmacokinetic characteristics expected of extended half-life YTE-antibodies. Conclusion. The BRII-196 and BRII-198 cocktail was well-tolerated, and maintains neutralization against currently reported circulating variants of concern. These preclinical and clinical results support further development of BRII-196 and BRII-198 as a therapeutic or prophylactic option for SARS-CoV-2.

4.
2021 IEEE International Conference on Bioinformatics and Biomedicine, BIBM 2021 ; : 1528-1533, 2021.
Article in English | Scopus | ID: covidwho-1722894

ABSTRACT

The ongoing global pandemic of Coronavirus Disease 2019 (COVID-19) poses a serious threat to public health and the economy. Rapid and accurate diagnosis of COVID-19 is essential to prevent the further spread of the disease and reduce its mortality. Chest Computed tomography (CT) is an effective tool for the early diagnosis of lung diseases including pneumonia. However, detecting COVID-19 from CT is demanding and prone to human errors as some early-stage patients may have negative findings on images. Recently, many deep learning methods have achieved impressive performance in this regard. Despite their effectiveness, most of these methods underestimate the rich spatial information preserved in the 3D structure or suffer from the propagation of errors. To address this problem, we propose a Dual-Attention Residual Network (DARNet) to automatically identify COVID-19 from other common pneumonia (CP) and healthy people using 3D chest CT images. Specifically, we design a dual-attention module consisting of channel-wise attention and depth-wise attention mechanisms. The former is utilized to enhance channel independence, while the latter is developed to recalibrate the depth-level features. Then, we integrate them in a unified manner to extract and refine the features at different levels to further improve the diagnostic performance. We evaluate DARNet on a large public CT dataset and obtain superior performance. Besides, the ablation study and visualization analysis prove the effectiveness and interpretability of the proposed method. © 2021 IEEE.

5.
Frontiers in Energy Research ; 9, 2022.
Article in English | Scopus | ID: covidwho-1705943

ABSTRACT

China is in a transition period—its government has been expanding imports and pushing itself to shift from a world factory to a world market. One of the aims is to promote energy reform and ensure energy security. Taking the resource-based regions of China as objects, based on 2003–2017 panel data, this paper investigates energy efficiency loss by the stochastic frontier approach and the effects of different technical inefficiency items. Surprisingly, quantitative results show that 99.9% energy efficiency loss in these regions is caused by technical inefficiency (which had never been found and discussed in previous studies). However, this does not mean that China’s efforts to expand imports as a way to improve energy efficiency and energy security are undesirable. Instead, interestingly, it is import (−0.083***) rather than industrial structure (0.524***) that can significantly reduce energy efficiency loss. Then, it employs the counter-fact test to quantify the positive accelerating effect of human capital (average as high as 4.1%) as a key factor of absorptive capacity in the technology spillover. Lastly, it puts forward the corresponding policy suggestions in energy fields, to solve the problem effectively, especially the “comprehensive technology spreading center” and “innovative three-dimensional talent supplementary and flow mechanism”. Copyright © 2022 Hao, Wang and Xue.

6.
IEEE/CVF International Conference on Computer Vision (ICCVW) ; : 1531-1540, 2021.
Article in English | Web of Science | ID: covidwho-1699347

ABSTRACT

Face recognition achieved excellent performance in recent years. However, its potential for unfairness is raising alarm. For example, the recognition rate for the special group of East Asian is quite low. Many efforts have spent to improve the fairness of face recognition. During the COVID-19 pandemic, masked face recognition is becoming a hot topic but brings new challenging for fair face recognition. For example, the mouth and nose are important to recognizing faces of Asian groups. Masks would further reduce the recognition rate of Asian faces. To this end, this paper proposes a fair masked face recognition system. First, an appropriate masking method is used to generate masked faces. Men, a data re-sampling approach is employed to balance the data distribution and reduce the bias based on the analysis of training data. Moreover, we propose an asymmetric-arc-loss which is a combination of arc-face loss and circle-loss, it is useful for increasing recognition rate and reducing bias. Integrating these techniques, this paper obtained fairer and better face recognition results on masked faces.

7.
Embase;
Preprint in English | EMBASE | ID: ppcovidwho-326764

ABSTRACT

The SARS-CoV-2 B.1.1.529 variant (Omicron) contains 15 mutations on the receptor-binding domain (RBD). How Omicron would evade RBD neutralizing antibodies (NAbs) requires immediate investigation. Here, we used high-throughput yeast display screening1,2 to determine the RBD escaping mutation profiles for 247 human anti-RBD NAbs and showed that the NAbs could be unsupervised clustered into six epitope groups (A-F), which is highly concordant with knowledge-based structural classifications3-5. Strikingly, various single mutations of Omicron could impair NAbs of different epitope groups. Specifically, NAbs in Group A-D, whose epitope overlap with ACE2-binding motif, are largely escaped by K417N, G446S, E484A, and Q493R. Group E (S309 site)6 and F (CR3022 site)7 NAbs, which often exhibit broad sarbecovirus neutralizing activity, are less affected by Omicron, but still, a subset of NAbs are escaped by G339D, N440K, and S371L. Furthermore, Omicron pseudovirus neutralization showed that single mutation tolerating NAbs could also be escaped due to multiple synergetic mutations on their epitopes. In total, over 85% of the tested NAbs are escaped by Omicron. Regarding NAb drugs, the neutralization potency of LYCoV016/LY-CoV555, REGN10933/REGN10987, AZD1061/AZD8895, and BRII-196 were greatly reduced by Omicron, while VIR-7831 and DXP-604 still function at reduced efficacy. Together, data suggest Omicron would cause significant humoral immune evasion, while NAbs targeting the sarbecovirus conserved region remain most effective. Our results offer instructions for developing NAb drugs and vaccines against Omicron and future variants.

8.
Aslib Journal of Information Management ; 2021.
Article in English | Scopus | ID: covidwho-1354365

ABSTRACT

Purpose: To better meet people's information needs under the public health crisis, this study explored the information needs and seeking behavior of college students in the context of the COVID-19 pandemic. Design/methodology/approach: This research utilized a survey and the convenience snowball sampling method. A sample of 400 college students was obtained. Findings: The results revealed that college students have paid great attention to COVID-19-related information. They sought the information mainly for personal protection, obtaining the latest information and seeking information for family and friends. Their COVID-19-related information needs were diverse;at different stages, the concerns were different. Social media and mass media were both found to be the most useful tools for seeking COVID-19 information. Too much repetitive information, unclear authoritative and reliable informational sources, and difficulties in judging the authenticity of the information were the most common obstacles for them in information seeking. Nevertheless, the majority of the students agreed that they were very satisfied and somewhat satisfied with the current information services. This did not affect the students' understanding of the importance of health services provided by libraries. Originality/value: Insights into the people's information needs and information-seeking behavior of this study could help the information providers to offer appropriate information in better ways to improve the public's virus protection capabilities and maintain the stability of social order. © 2021, Emerald Publishing Limited.

9.
Chinese Journal of Environmental Engineering ; 15(6):1831-1839, 2021.
Article in Chinese | Scopus | ID: covidwho-1299695

ABSTRACT

Hand washing enhanced by the Covid-19 has caused more surfactants to flow into wastewater treatment plants (WWTPs), which might affect both wastewater treatment and sludge disposal. Surfactants in municipal wastewater are usually at 5~20 mg·L−1, but it could climb to 10~30 mg·L−1 during the pandemic. Only about 1% of the influent surfactants generally remains in the effluent, and approximately 10%~20% is adsorbed into excess sludge. Although the content of surfactants in wastewater is not so high, their special amphiphilic molecular structures could reduce oxygen transfer efficiency, destroy sludge flocs, and affect the activity and abundance of microorganisms associated with nitrogen and phosphorus removal. As for sludge treatment, however, surfactants seem positive on dehydration, cell disintegration, solubilizing sludge flocs, and even anaerobic digestion like hydrolysis and acidification. Thus, it is a high priority to address the source, structure and migration &transformation of surfactants first, then to elucidate their influences and associated countermeasures on wastewater treatment, and finally to demonstrate their positive impacts on sludge treatment/disposal. The review is proposed to pay attention to the long-term effect of surfactants at a high content due to the pandemic, so as to study future operational measures that could alleviate the negative effects on wastewater treatment and simultaneously utilizes the positive effects on sludge treatment. © 2021, Science Press. All right reserved.

10.
Chinese General Practice ; 24(20):2589-2593, 2021.
Article in Chinese | Scopus | ID: covidwho-1289245

ABSTRACT

Severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)was initially thought to mainly affect the respiratory system. A growing body of research has found that SARS-CoV-2 infection can affect multiple human organ systems, and heart is a major target organ secondary to lung. COVID-19-associated cardiac injury is often seen clinically, about 1%-7% of which is myocarditis. COVID-19-associated myocarditis often has a poor outcome. However, the possible pathogenesis mechanisms of COVID-19-associated cardiac injury, and its progression to COVID-19-associated myocarditis, as well as related pathophysiological changes are still unknown. Available data analysis has revealed that the recognized mechanism of cardiac injury in COVID-19 is ACE2-mediated cardiac injury, and cytokine storm-mediated or immune-mediated cardiac injury is only suggestive currently. Due to limited use of cardiac MRI and endocardial biopsy as well as insufficient autopsy findings and other basic research data in patients with COVID-19-associated myocarditis, the diagnosis and treatment of COVID-19-associated myocarditis are challenges that still exist for clinicians. We reviewed the possible pathophysiological mechanisms of COVID-19-associated myocarditis, which will contribute to improving medical workers' understanding of this disease so that its related mortality may be reduced. Copyright © 2021 by the Chinese General Practice.

11.
American Journal of Translational Research ; 13(4):3650-3657, 2021.
Article in English | EMBASE | ID: covidwho-1227495

ABSTRACT

Objective: This study was designed to explore the clinical characteristics, outcomes, and related influencing factors for asymptomatic patients with positive Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-Cov-2) nucleic acid test. Methods: Clinical data of 1568 patients with positive SARS-Cov-2 nucleic acid test (SNAT) were collected retrospectively. The patients were assigned to an asymptomatic group and a symptomatic group according to the existence of clinical symptoms when they got positive result in nucleic acid test, and the clinical data of the two groups were analyzed and compared. In addition, the data of asymptomatic patients who showed clinical symptoms later and the results of two-week follow-up after cure were analyzed. Results: Among all enrolled patients, there were 1489 patients with positive symptoms and 79 asymptomatic patients, including 34 patients who developed symptoms during treatment. Logistic analysis revealed that age ≤45 years (OR=2.722, P<0.001), history of diabetes mellitus (OR=0.446, P=0.007), and history of cancer (OR=0.259, P=0.008) were independent factors for asymptomatic presentation in patients with positive SNAT, and age ≥46 years (OR=1.562, P=0.012) and history of hypertension (OR=2.077, P<0.001) were risk factors for the occurrence of clinical symptoms in asymptomatic patients with positive SNAT during hospitalization. During the follow-up after cure, 8 patients got reoccurring positive SNAT result. Conclusion: Asymptomatic patients with positive SNAT are mostly young and middle-aged people, and old age and hypertension are risk factors for the occurrence of positive clinical characteristics in asymptomatic patients.

12.
Jiaotong Yunshu Xitong Gongcheng Yu Xinxi/Journal of Transportation Systems Engineering and Information Technology ; 20(6):71-76 and 98, 2020.
Article in Chinese | Scopus | ID: covidwho-1005187

ABSTRACT

COVID-19 has caused huge negative impacts on traffic and transportation. Existing research focused on the impact of COVID-19 on the traffic during the outbreak phase. There are still few studies related to the impact of COVID-19 on travel behavior during the post-epidemic phase. This paper analyzed the impact of COVID-19 during the post-epidemic phase, travelers' demographic characteristics, and perception of the COVID-19 severity on the elderly's travel behavior, with the confirmative factor analysis and Logit modeling. The results show that COVID-19 and perception of its severity have no significant impact on the elderly's short-distance trips. However, they have a significant impact on the elderly's willingness to travel by bus. Furthermore, these two factors have significant impacts on the elderly's trip frequency and bus trips. Copyright © 2020 by Science Press.

13.
Academic Journal of Second Military Medical University ; 41(5):474-480, 2020.
Article in Chinese | EMBASE | ID: covidwho-743064

ABSTRACT

Objective To investigate the efficacy of neutralizing antibodies induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) receptor-binding domain (RBD) and spike (S) protein S1 subunit. Methods The SARS-CoV-2 RBD and mouse immunoglobulin G1 (IgG1) Fc fragment (mFc) fusion protein expression plasmid pVRCRBD- mFc was constructed and transfected into human embryonic kidney 293T cells. The RBD-mFc fusion protein in the cell supernatants was detected by Western blotting. The effect of RBD-mFc in cell supernatants and CHO recombinant S1-human IgG1 Fc (S1-hFc) fusion protein on SARS-CoV-2 infection was detected by microneutralization test. BALB/c mice were immunized with plasmid pVRC-RBD-mFc and S1-hFc fusion protein via intramuscular injection. Anti-S1 IgG antibodies in mouse sera were detected by enzyme-linked immunosorbent assay (ELISA), and the virus neutralization activity of mouse sera was detected by microneutralization test. Results The RBD-mFc fusion protein could be detected in the culture supernatants of 293T cells transfected with the plasmid pVRC-RBD-mFc, the concentrated supernatants and the S1- hFc fusion protein could inhibit SARS-CoV-2 infection on Vero E6 cells in a concentration-dependent manner. Anti-S1 IgG antibodies could be detected in the sera of mice immunized with plasmid pVRC-RBD-mFc and S1-hFc fusion protein, and the sera of both groups could neutralize SARS-CoV-2 infection. The serum antibody titers and virus neutralization activity of S1- hFc fusion protein immunized mice were significantly higher than those of plasmid pVRC-RBD-mFc immunized mice (both P<0.01). Conclusion Both SARS-CoV-2 RBD and S1 subunit may be used as effective vaccine antigens. Compared with DNA vaccine, recombinant subunit vaccine can induce neutralizing antibody more effectively..

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