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Tribo-tests play a crucial role in the evaluation of the material performance of tribo-pairs. Traditionally, tribo-tests are performed onsite and tightly depend on experienced human operators. However, some public health emergencies such as covid-19 have a substantial impact on daily human life, including product and service systems. Therefore, this chapter aims to develop a new tribo-test service pattern, that is, digital twin enhanced remote tribo-test. A digital twin enhanced tribo-test service framework is proposed, which includes the modeling stage and the application stage of tribo-test service. A case study is presented to showcase how to implement the proposed framework. © 2022 Elsevier Inc. All rights reserved.
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We identify fixed-income mutual funds as an important contributor to the unusually high selling pressure in liquid asset markets during the COVID-19 crisis. We show that mutual funds experienced pronounced investor outflows amplified by their liquidity transformation. In meeting redemptions, funds followed a pecking order by first selling their liquid assets, including Treasuries and high-quality corporate bonds, which generated the most concentrated selling pressure in these markets. Overall, the estimated price impact of mutual funds was sizable at a third of the increase in Treasury yields and a quarter of the increase in corporate bond yields during the COVID-19 crisis. © 2022 The Author(s). Published by Oxford University Press on behalf of The Society for Financial Studies. All rights reserved.
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OBJECTIVE: To establish a rapid detection and genotyping method for SARS-CoV-2 Omicron BA.4/5 variants using CRISPPR-Cas12a gene editing technology. METHODS: We combined reverse transcription-polymerase chain reaction (RT-PCR) and CRISPR gene editing technology and designed a specific CRISPPR RNA (crRNA) with suboptimal protospacer adjacent motifs (PAM) for rapid detection and genotyping of SARS- CoV-2 Omicron BA.4/5 variants. The performance of this RT- PCR/ CRISPPR-Cas12a assay was evaluated using 43 clinical samples of patients infected by wild-type SARS-CoV-2 and the Alpha, Beta, Delta, Omicron BA. 1 and BA. 4/5 variants and 20 SARS- CoV- 2-negative clinical samples infected with 11 respiratory pathogens. With Sanger sequencing method as the gold standard, the specificity, sensitivity, concordance (Kappa) and area under the ROC curve (AUC) of RT-PCR/CRISPPR-Cas12a assay were calculated. RESULTS: This assay was capable of rapid and specific detection of SARS- CoV-2 Omicron BA.4/5 variant within 30 min with the lowest detection limit of 10 copies/µL, and no cross-reaction was observed in SARS-CoV-2-negative clinical samples infected with 11 common respiratory pathogens. The two Omicron BA.4/5 specific crRNAs (crRNA-1 and crRNA-2) allowed the assay to accurately distinguish Omicron BA.4/5 from BA.1 sublineage and other major SARS-CoV-2 variants of concern. For detection of SARS-CoV-2 Omicron BA.4/5 variants, the sensitivity of the established assay using crRNA-1 and crRNA-2 was 97.83% and 100% with specificity of 100% and AUC of 0.998 and 1.000, respectively, and their concordance rate with Sanger sequencing method was 92.83% and 96.41%, respectively. CONCLUSION: By combining RT-PCR and CRISPPR-Cas12a gene editing technology, we successfully developed a new method for rapid detection and identification of SARS-CoV-2 Omicron BA.4/5 variants with a high sensitivity, specificity and reproducibility, which allows rapid detection and genotyping of SARS- CoV-2 variants and monitoring of the emerging variants and their dissemination.
Subject(s)
COVID-19 , Humans , CRISPR-Cas Systems , Genotype , Reproducibility of Results , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2/genetics , RNA , COVID-19 TestingABSTRACT
In response to the COVID-19 outbreak, the governments of different countries adopted restrictions, such as locking down cities and restricting travel and social contact. Online health communities (OHCs) with specialized physicians have become an important way for the elderly to access health information and social support, which has expanded their use since the outbreak. This paper examines the factors influencing elderly people's behavior in terms of the continuous use of OHCs from a social support perspective to understand the impact of public health emergencies. Research collected data from March to April 2019, February 2020, and August 2021 in China. A total of 189 samples were collected and analyzed by using SmartPLS. The results show that (1) social support to the elderly during different stages has different influences on their sense of community and (2) the influence of the sense of community on the intention to continuously use OHCs also seems to change over time. The results of this study provide important implications for research and practice related to both OHCs and COVID-19. © 2022 IGI Global. All rights reserved.
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Since the pandemy, the carrying capacity of major railway stations has been restricted to respect the distance. In Asian metropolises, a tech-driven flow management system reinforces the surveillance of travellers and help the maintenance of a top affluence in station's buildings. In France, an attempt is made to space out travelers with less intrusive processes, such as signage and boarding protocol adaptation. A comparison between these two responses leads us to question what physical distancing does, here and there, to the practices and places of transit and to the economic injonction to densify flows in and around stations until now. Articulating the approaches of crowding science and health regulation in transit environments, the article presents a transcontinental comparison, and then questions the status of major station as post pandemic urbanism showroom.
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Objective: To study the clinical characteristics of diabetes mellitus with Coronavirus disease 2019 (COVID-19) and explore the possible mechanism of diabetes predisposition. Method(s): A single center, retrospective and observational study was used to collect 48 inpatients diagnosed with COVID-19 who were admitted to the first ward of the third department of infection, Raytheon hospital, Wuhan from February 23, 2020 to March 30, 2020. Demographic data, symptoms, laboratory tests, comorbidities, treatments and clinical outcomes have been collected. The patients were divided into non-diabetic group and diabetic group according to the combination of diabetes. The clinical data and laboratory test results of the two groups were observed, and the t test, non-parametric test and Chi square test were used for comparison. Result(s): All the 5 patients with COVID-19 diabetes mellitus had fever and respiratory symptoms, chest CT was consistent with typical COVID-19 imaging features, and novel coronavirus nucleic acid test results were positive. There were no statistically significant differences in age, gender composition, co-existing diseases, clinical symptoms, clinical typing, disease course and treatment plan between the diabetic group and the non-diabetic group (P>0.05).There was a statistically significant difference in fasting blood glucose between the non-diabetic group and the diabetic group (P<0.05).The difference of fasting blood glucose at discharge from the diabetes group compared with that at admission was also statistically significant (P<0.05).There was no statistically significant difference between the two groups in other laboratory examination indexes (P>0.05). Conclusion(s): COVID-19 patients with diabetes are mainly manifested by fever and respiratory symptoms.Chest CT shows typical COVID-19 imaging features.Copyright © 2020 by the Chinese Medical Association.
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Objective We aimed to review the data available to explore prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection in the real world. Methods We searched observational cohort studies and case-control studies that described the SARS-CoV-2 reinfections in PubMed, Embase, Web of Science, CNKI and WanFang Data from inception to 11 Dec 2022. Studies, data extracted and quality assessed were selected according to strict inclusion exclusion criteria. All analyses were using Stata version 16.0. Results A total of 24 studies were included, involving 78 635 cases of SARS-CoV-2 reinfection and 6 616 869 cases of SARS-CoV-2 primary infection. In cases after the primary SARS-CoV-2 infection, the pooled prevalence of reinfection was 2.06% (95% CI: 1.73% – 2.40%). Compared with other age groups, the secondary infection rate was higher in those aged 40 – < 50 years 2.97% (95% CI: −1. 20%–7 14%) and 50–<60 years 2. 32% (95% CI: –0.74%–5.38%). In vaccination status group, the pooled prevalence was 5.47% (95% CI: 1.99%–8.95%) in unvaccinated cases, 1.85% (95% CI: 1.63%–2.08%) for those received partial COVID-19 vaccination, and 1.11% (95% CI: 0.34%–1.89%) for those received fully vaccination. In addition, the pooled prevalence of SARS-CoV-2 reinfection was 6.02% (95% CI: 5.67%–6. 37%) in the health care workers. Conclusions There is a risk of SARS-CoV-2 reinfection, but the results of this global real-world meta-analysis showed that the rate of reinfection is not high. It is recommended to scientifically understand the risk of SARS-CoV-2 reinfection, strengthen public health education, maintain healthy habits, and reduce the risk of SARS-CoV-2 reinfection. © 2023, Publication Centre of Anhui Medical University. All rights reserved.
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The existing studies have applied metamorphic testing technique to testing the medical image classification models, effectively alleviating the test oracle problem and reducing the testing difficulty. However, existing methods mainly focus on constructing metamorphic relations by using general image transformation methods, without combining the knowledge characteristics of medical imaging domain, resulting in problems such as low validity of metamorphic relations. According to the above problems, this paper based on the premise of conforming to the real scenario of image diagnosis, combining the key information of medical image semantics, and constructing general metamorphic relations in this field from three dimensions: the characteristics of medical images in real environment, the regular changes of lesion stage in images and the motion artifacts produced by patients in the process of filming. The medical images classification models of COVID-19 were also selected for instance validation, and the metamorphic relations were quantitatively analyzed to detect inconsistency in the classification results of different models and to assess the robustness of the model. The experimental results show that the constructed metamorphic relations by the key information of medical image semantics are able to detect inconsistencies in the models with a high detection capability, with the inconsistency percentage reaching up to 38.05%. This method can also be extended to test different types of medical image classification models. © 2022 IEEE.
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As an upper-middle-income country, China has a vast territory, a large population and substantial variations in the nature of mental health service provision. Guangzhou, one of the five biggest cities in China, is considered as indicative of the current development of mental health services in a more economically developed part of China. In this paper, we first introduce mental health services in Guangzhou and their historical development: from the rising development of mental health care (1949 to the mid-1960s), the stagnant development period of the psychiatric hospitals (1966-1976), the rapid development period of the psychiatric hospitals (1978 to the 1990s), to the integrated development period of community mental health care (2000-2020). This historical trajectory partly reflects the development of mental health services across China. Second, from the public health perspective, we introduce the current mental health care delivery system and resources in Guangzhou, including the psychiatric specialist hospitals, psychiatric units of general hospitals, and community mental health care. Third, based on the current mental health service system, we highlight community mental health care in Guangzhou. We will describe these elements of the mental health system under the following headings: organizational setup, management, and services. We also explore the design of community mental health service models and the challenges in the post-covid-19 era. Finally, we provide considerations and recommendations for mental health service delivery in Guangzhou in the future.Copyright © 2023 The Authors
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Pickering emulsions were prepared by phacoemulsification in an ice water bath with squalene as the oil phase and an aluminum adjuvant as the particle stabilizer. The effects of formulation and process conditions on the size and distribution of the Pickering emulsions were investigated. Pickering emulsions prepared under the optimal prescription and process conditions were mixed with a peptide antigen to obtain a peptide vaccine. The optimal prescription and process condition of the Pickering emulsion is as follows: squalene as the oil phase, ultra-pure water as the water phase with 5 mg/ml aluminum adjuvant, and an ultrasonication time of 4 min at 200 W power. BALB/c mice were immunized with the peptide vaccine, and the ability of the Pickering emulsion as an immunological adjuvant to improve the efficacy of the peptide vaccine was evaluated. Under optimal conditions, a Pickering emulsion with a small particle size (430.8 nm), uniform distribution (polydispersion index of 16.9%), and zeta potential of 31.5 mV, was obtained. Immunological results showed that the serum specific antibody level in the vaccinated group reached 1×104 after three immunizations. The proportion of CD4+T cells and CD4/CD8 cells was significantly higher (P < 0.05) in the vaccinated groups than the blank control group. Further, cytokine (TNF-α) secretion decreased in the aluminum adjuvant and Pickering emulsion groups but increased in the Freund's adjuvant group. All three vaccinated groups of mice exhibited low but detectable levels of IFN-γ secretion. © 2023
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Interpreting palliative care conversations can be stressful due to the emotions and complex terminology involved, as well as the emphasis on fostering patient autonomy and disclosing prognosis transparently. To improve the quality of care for patients speaking different languages, a palliative care physician and social worker approached the director of interpreter services offering to provide sessions to address vicarious trauma. With interpreter input, they developed a series of monthly Dialogues in Palliative Care. This paper recounts how this supportive educational endeavor became a holistic approach to medical interpreters' occupational safety and health. The relationship between the clinicians and interpreters enabled a smooth transition to weekly emotional support for the interpreters and the modeling of a culture of care during the Covid-19 pandemic. Interpreters are integral members of the health care team and are uniquely vulnerable to emotional stress. They deserve a work environment that mitigates vicarious trauma. © 2022 International Association of Translation and Intercultural Studies. All rights reserved.
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Objective We aimed to review the data available to explore prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reinfection in the real world. Methods We searched observational cohort studies and case-control studies that described the SARS-CoV-2 reinfections in PubMed, Embase, Web of Science, CNKI and WanFang Data from inception to 11 Dec 2022. Studies, data extracted and quality assessed were selected according to strict inclusion exclusion criteria. All analyses were using Stata version 16.0. Results A total of 24 studies were included, involving 78 635 cases of SARS-CoV-2 reinfection and 6 616 869 cases of SARS-CoV-2 primary infection. In cases after the primary SARS-CoV-2 infection, the pooled prevalence of reinfection was 2.06% (95% CI: 1.73% - 2.40%). Compared with other age groups, the secondary infection rate was higher in those aged 40 - < 50 years 2.97% (95% CI: -1. 20%-7 14%) and 50-<60 years 2. 32% (95% CI: -0.74%-5.38%). In vaccination status group, the pooled prevalence was 5.47% (95% CI: 1.99%-8.95%) in unvaccinated cases, 1.85% (95% CI: 1.63%-2.08%) for those received partial COVID-19 vaccination, and 1.11% (95% CI: 0.34%-1.89%) for those received fully vaccination. In addition, the pooled prevalence of SARS-CoV-2 reinfection was 6.02% (95% CI: 5.67%-6. 37%) in the health care workers. Conclusions There is a risk of SARS-CoV-2 reinfection, but the results of this global real-world meta-analysis showed that the rate of reinfection is not high. It is recommended to scientifically understand the risk of SARS-CoV-2 reinfection, strengthen public health education, maintain healthy habits, and reduce the risk of SARS-CoV-2 reinfection.Copyright © 2023, Publication Centre of Anhui Medical University. All rights reserved.
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2019-nCoV has a up to 96% homology with the gene sequence of a bat coronavirus. By comparing its 7 conserved non-structural proteins, it is found that 2019-nCoV belongs to SARS related coronaviruses(SARSr-CoV). The receptor for 2019-nCoV entering cells is the same as that for SARSr-CoV, and angiotensin-converting enzyme 2 (ACE2) is a common cross-genus receptor. This article first elaborates the interspecies transmission and genetic variation, then briefly discusses the receptors on the surface of human cells (such as ACE2 and APP4), which cause human infection and encode five proteins in the viral genome, therefore are important targets for development of antiviral drugs. The article reviews eight promising anti-coronavirus drugs, including three anti-HIV drugs (Lopinavir/Ritonavir, Danoprevir/Ritonavir, Darunavir), two anti-Ebola virus drugs (Remdesivir, Galidesivir), two anti-influenza virus drugs (Arbidol, Favipiravir) and one anti-malarial drug (chloroquine phosphate). Among them, Remdesivir, Abidol and Favipiravir have strong inhibitory effects on 2019-nCoV, they may be the most promising drugs under investigation.Copyright © 2020 by the Chinese Medical Association.
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2019-nCoV has a up to 96% homology with the gene sequence of a bat coronavirus. By comparing its 7 conserved non-structural proteins, it is found that 2019-nCoV belongs to SARS related coronaviruses(SARSr-CoV). The receptor for 2019-nCoV entering cells is the same as that for SARSr-CoV, and angiotensin-converting enzyme 2 (ACE2) is a common cross-genus receptor. This article first elaborates the interspecies transmission and genetic variation, then briefly discusses the receptors on the surface of human cells (such as ACE2 and APP4), which cause human infection and encode five proteins in the viral genome, therefore are important targets for development of antiviral drugs. The article reviews eight promising anti-coronavirus drugs, including three anti-HIV drugs (Lopinavir/Ritonavir, Danoprevir/Ritonavir, Darunavir), two anti-Ebola virus drugs (Remdesivir, Galidesivir), two anti-influenza virus drugs (Arbidol, Favipiravir) and one anti-malarial drug (chloroquine phosphate). Among them, Remdesivir, Abidol and Favipiravir have strong inhibitory effects on 2019-nCoV, they may be the most promising drugs under investigation.Copyright © 2020 by the Chinese Medical Association.
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2019-nCoV has a up to 96% homology with the gene sequence of a bat coronavirus. By comparing its 7 conserved non-structural proteins, it is found that 2019-nCoV belongs to SARS related coronaviruses(SARSr-CoV). The receptor for 2019-nCoV entering cells is the same as that for SARSr-CoV, and angiotensin-converting enzyme 2 (ACE2) is a common cross-genus receptor. This article first elaborates the interspecies transmission and genetic variation, then briefly discusses the receptors on the surface of human cells (such as ACE2 and APP4), which cause human infection and encode five proteins in the viral genome, therefore are important targets for development of antiviral drugs. The article reviews eight promising anti-coronavirus drugs, including three anti-HIV drugs (Lopinavir/Ritonavir, Danoprevir/Ritonavir, Darunavir), two anti-Ebola virus drugs (Remdesivir, Galidesivir), two anti-influenza virus drugs (Arbidol, Favipiravir) and one anti-malarial drug (chloroquine phosphate). Among them, Remdesivir, Abidol and Favipiravir have strong inhibitory effects on 2019-nCoV, they may be the most promising drugs under investigation.Copyright © 2020 by the Chinese Medical Association.
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The blended educational method has become a common way of teaching and learning in the post-COVID-19 era. However, the related research on the selection model for the blended design teaching service quality solution is still an important research gap during this period. Therefore, this study proposed a hybrid method of fuzzy analytic network process (FANP) and technique for order preference by similarity to ideal solution (TOPSIS) to analyse the dimensions, indicators and alternatives of blended design teaching service quality. As for the findings of this research, the dimension of assurance is the most vital factor, followed by responsiveness, reliability and empathy. Meanwhile, this research discovered that the top three significant alternatives are "Employees are trustworthy”, "Safe transaction mechanism and environment” and "Personalised needs of customers”. Also, we found that dimensions utilised to evaluate the quality of education service are similar whether in the post COVID-19 era, in the COVID-19 epidemic or prior to the COVID-19 pandemic. The main contribution of this study is to establish a multi-criteria decision-making (MCDM) model for the ranking of the blended design teaching service quality index and solution under a fuzzy environment. Finally, the research findings of this study have a guiding role, thereby becoming a guide for the industries related to hybrid design education to maintain good service quality in similar scenarios in the future. © 2023 by the authors.
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Objective: To study the clinical characteristics of diabetes mellitus with Coronavirus disease 2019 (COVID-19) and explore the possible mechanism of diabetes predisposition. Method(s): A single center, retrospective and observational study was used to collect 48 inpatients diagnosed with COVID-19 who were admitted to the first ward of the third department of infection, Raytheon hospital, Wuhan from February 23, 2020 to March 30, 2020. Demographic data, symptoms, laboratory tests, comorbidities, treatments and clinical outcomes have been collected. The patients were divided into non-diabetic group and diabetic group according to the combination of diabetes. The clinical data and laboratory test results of the two groups were observed, and the t test, non-parametric test and Chi square test were used for comparison. Result(s): All the 5 patients with COVID-19 diabetes mellitus had fever and respiratory symptoms, chest CT was consistent with typical COVID-19 imaging features, and novel coronavirus nucleic acid test results were positive. There were no statistically significant differences in age, gender composition, co-existing diseases, clinical symptoms, clinical typing, disease course and treatment plan between the diabetic group and the non-diabetic group (P>0.05).There was a statistically significant difference in fasting blood glucose between the non-diabetic group and the diabetic group (P<0.05).The difference of fasting blood glucose at discharge from the diabetes group compared with that at admission was also statistically significant (P<0.05).There was no statistically significant difference between the two groups in other laboratory examination indexes (P>0.05). Conclusion(s): COVID-19 patients with diabetes are mainly manifested by fever and respiratory symptoms.Chest CT shows typical COVID-19 imaging features.Copyright © 2020 by the Chinese Medical Association.
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This paper presents a portable, fast and accurate electrochemical impedance spectroscopy (EIS) device with 8-well interdigitated electrode chips for biomarker detection. The design adopts low crest factor multisine signal synthesis at low frequencies (<1 kHz) and single-tone signals at high frequencies (>1 kHz), which significantly increases measurement speed without sacrificing accuracy. In addition, the low excitation amplitude of 10 mV preserves impedance linearity and protects the biosamples. The system achieved an average magnitude accuracy error of 0.30% in the frequency range of interest and it requires only 0.46 s to scan 28 frequency points from 10 Hz to 1 MHz. Experiments were conducted to test the capability to detect antibodies against SARS-CoV-2. Gold nanoparticles bound with protein G (GNP-G) were employed as the conjugated secondary antibody probe to detect anti-SARS-CoV-2 IgG in serum. A highly statistical significance (p = 7×10−6) could be found in the impedance data at 10 kHz. The impedance magnitude alteration caused by the GNP-G of the positive and negative groups were 27.2%±13.6% and 4.1%±1.7%, respectively. The results imply that the proposed system enables rapid COVID-19 antibody biomarker detection. Moreover, the EIS system and GNPs have the potential to be modified to detect other biomarkers. © 2022 The Author(s)
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Background: Online learning is currently adopted by educational institutions worldwide to provide students with ongoing education during the COVID-19 pandemic. However, online learning has seen students lose interest and become anxious, which affects learning performance and leads to dropout. Thus, measuring students' engagement in online learning has become imperative. It is challenging to recognize online learning engagement due to the lack of effective recognition methods and publicly accessible datasets. Methods: This study gathered a large number of online learning videos of students at a normal university. Engagement cues were used to annotate the dataset, which was constructed with three levels of engagement: low engagement, engagement, and high engagement. Then, we introduced a bi-directional long-term recurrent convolutional network (BiLRCN) for online learning engagement recognition in video. Result: An online learning engagement dataset has been constructed. We evaluated six methods using precision and recall, where BiLRCN obtained the best performance. Conclusions: Both category balance and category similarity of the data affect the performance of the results;it is more appropriate to consider learning engagement as a process-based evaluation;learning engagement can provide intervention strategies for teachers from a variety of perspectives and is associated with learning performance. Dataset construction and deep learning methods need to be improved, and learning data management also deserves attention. © 2022 by the authors.