ABSTRACT
Viral infections are global health concerns that can cause high infection and mortality rates, as of the example from SARS-CoV-2 pandemic. Although conventional methods, e.g., polymerize chain reaction (PCR), can provide reliable and robust detection results, they are often time- and cost-consuming, limiting their application in resource-poor settings. Recently, paper-based devices, as a new biosensing technique, have emerged as a promising tool to conventional methods for pathogen detection including bacteria and virus. In this chapter, we provide a comprehensive introduction and insights on the development of paper-based devices for the pathogen detection in water. Firstly, the substrate materials and fabrication methods for paper-based devices are introduced. Engineering assay onto paper-based devices for virus detection is subsequently discussed for the rapid and on-site monitoring. We also compare the strengths and drawbacks between paper-based devices and the conventional analytical methods for virus detection, including culture method, biochemical test, immune assay, and molecular method. This chapter also discusses the feasibility of paper-based devices for point-of-use detection in water matrix, and the challenges and prospects of paper-based devices in water and environmental monitoring. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.
ABSTRACT
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also known as COVID-19, is much more difficult to transmit through the ocular surface than that through the mouth and nose. However, the available evidence has suggested the possibility of ocular surface transmission, especially in medical staff. In this paper, we describe the existing SARS-CoV-2 ocular surface symptoms, the possible mechanism of SARS-COV-2 entering ocular surface cells and SARS-COV-2 transmission through ocular surface. In addition, the existing and future possible research directions of SARS-CoV-2 transmission through ocular surface were analyzed, so as to provide new ideas and methods for clinical treatment of SARS-CoV-2 from the perspective of ocular surface.Copyright © 2021, Xinxiang Medical University. All rights reserved.
ABSTRACT
Background Delta and Omicron are two main variants that have been prevalent since 2021. However, the Omicron variant of severe acute respiratory syndrome coronavirus 2 shows a less severe clinical presentation and high transmissibility. Therefore, we carried out this retrospective study to evaluate Omicron severity compared with the Delta variant and further comprehend the differences in clinical characteristics in patients with the Omicron variant. Methods We extracted clinical data and compared clinical severity, symptoms, vaccination status, laboratory parameters, viral shedding time, and computed tomography (CT) imaging between the two groups of patients, which included 109 COVID-19 cases with the Delta variant and 183 cases with the Omicron variant, from January 19 to April 1, 2022, in Beijing Ditan Hospital. In addition, the Beijing Center for Disease Prevention and Control conducted whole-genome sequencing. Results We obtained 94 strains of variants of concern/Delta and 110 strains of variants of concern/Omicron. For the 110 Omicron strains, three were assigned as BA.1.1, 53 as BA.2, and 54 as BA.2.2. Among patients with the Delta variant, 54% (59/109) were moderate, which was significantly higher than that of patients with the Omicron variant (7% (12/183), P < 0.001). The number of patients with mild symptoms in the Omicron group was significantly higher than in the Delta group (80% vs. 35%, P < 0.001). Compared with the Omicron group, patients with underlying diseases or obesity, 60 years or older, or unvaccinated in the Delta group had more severe disease, and there was a significant difference between the two groups. The viral shedding time in the Omicron group was shorter than in the Delta group ((11.9 ± 5.9) vs. (14.0 ± 5.8) days, P = 0.003). Among the 183 patients in the Omicron group, 104 (57%) had dry or sore throat symptoms, more than those in the Delta group (34% (37/109);P < 0.001). In the Delta group, patients in the moderate group had more fever and cough symptoms than those in the mild group. The remission time of CT imaging in the Omicron group was shorter than in the Delta group ((9.0 ± 5.2) vs. (13.2 ± 4.2) days, P = 0.018). Conclusions Patients with Delta variants are more likely to have pneumonia, mainly with fever and cough symptoms, while patients with the Omicron variant are mostly mild, with more prominent dry or sore throat symptoms. In addition, patients with the Omicron variant have a short viral shedding time and rapid absorption of pneumonia. © Wolters Kluwer Health, Inc. All rights reserved.
ABSTRACT
Objective To understand the status of COVID-19 vaccination among elderly adults in long-term care facilities and analyze the influencing factors so as to provide scientific basis for improving the policy of COVID-19 vaccination. Methods The socio-demographic characteristics, disease-related data, disability, and COVID-19 vaccination status of 575 elderly adults who resided in long-term care facilities in Shaanxi Province were collected via Sojumpin in January 2022. Factors that affected non-vaccinated elderly adults were analyzed by using the SPSS 25.0 software. Results Of the included 575 participants, 199 (34. 6%) were not vaccinated against COVID-19. Univariate analysis showed that COVID-19 vaccination was associated with age, room type, length of stay, marital status, number of children, chronic diseases (i.e., diabetes, stroke, dementia), disability degree, and long-term medication use. Logistic regression analysis demonstrated that age of 90 years or above (OR =4. 25), triple room (OR = 6.17), moderate disability (OR = 2. 94), severe disability (OR =6. 67), long-term medication use (OR = 1.81), and stroke (OR =1. 74) were independent risk factors for not injecting COVID-19 vaccine. Conclusion The COVID-19 vaccination coverage rate of elderly adults in long-term care facilities needs to be improved, and more attention should be paid to the high-risk groups (e.g., who are older, and have disability, long-term medication use, or stroke).Copyright © 2023 Xi'an Medical University. All rights reserved.
ABSTRACT
The aim of this study was to explore the effects of the moral cognition of gifted elementary schools students on their attitudes toward COVID-19. The study further investigated the changes in their emotions during the pandemic and the moderating effects of their emotions on the relationship between their moral cognition and attitudes toward patients with COVID-19. Various factors influence the moral cognition of children, such as age, sex, intelligence level, and personality. Moreover, their surrounding environments, particularly home and school environments, strongly affect their moral cognition. Therefore, various studies have explored relevant factors, such as education level, role replacement, peer relationship, family economic status, family structure, family emotion, religious belief, and sociocultural background. Nevertheless, the question regarding the attitudes of gifted children with outstanding potential toward moral issues should be explored. Lovecky (1997) indicated that gifted children are highly concerned about moral issues since childhood and that they have an excellent understanding of moral issues. Compared with their peers with a relatively low level of intelligence, gifted children have an improved understanding of fairness, justice, and responsibility toward he self and others (Gross, 1993), and this thus engenders high levels of moral sensitivity (Piechowski, 1991). Therefore, the question of whether the levels of these students' moral perceptions vary depending on grade, sex, or sociocultural identity warrants exploration. Gifted students differ from others intellectually, socially, emotionally, and physically;however, their ability to cognitively understand moral issues is higher than their ability to emotionally adjust to such issues (Clark, 2002/2007). Accordingly, they need opportunities to discuss moral issues around them and promote their moral growth (Lovecky, 1997). Epidemics exert strong negative effects on the general public;this fact invoked curiosity in the research fraternity regarding the effects of epidemics on gifted students belonging to different grades, sexes, and sociocultural identities. Questions arose regarding the effects of emotions on the moral perceptions of gifted students and whether such effects further affect the students' moral behaviors and attitudes. Studies on moral education in gifted students have not reported any major outcomes;this might be because of the lack of an association between moral cognition and moral practice (Liu, 2002). From an educational perspective, studies have explored the efforts of schools in educating children and constructing their moral cognition;gifted students perform better in making ethical choices than do other students. The COVID-19 may be the first real-life pandemic situation experienced by young students. Therefore, students must receive information related to health and epidemic prevention. The question of whether the attitudes of gifted and ordinary elementary school students vary depending on various factors (grade, sex, and sociocultural identity) in a real setting must be explored. Moreover, whether cognition and attitude are related remains to be determined. Whether the levels of students' moral cognition can help predict their attitudes toward epidemics and diseases also warrants clarification. Accordingly, on the basis of the theory of moral cognition development in children, the present study investigated the current status of moral cognition levels, emotions, and attitudes toward epidemics and patients in gifted and ordinary students and compared the findings between the two cohorts. The study findings may serve as a reference for designing ethics courses for gifted students with special needs in order to cultivate their sense of social responsibility and civic awareness and cultivate the virtues of knowing, loving, and doing good. This study included a total of 887 elementary school students (gifted, 515;ordinary, 372). Three research tools - the Behavior Defining Questions Test, Epidemic and Patient Attitude Scale, and Emotion Scale - were used for data collection and analysis. The results revealed no significant differences between gifted and ordinary students in terms of moral cognitive performance. Regarding the epidemic-related emotions of students belonging to various grades and sexes, this study determined that the ordinary students expressed higher levels of belief, fear, surprise, and sadness than did the gifted students;middle- and higher-grade gifted students expressed fear, surprise, sadness, and disgust;and boys expressed higher levels of sadness than did girls. The levels of moral attitudes toward epidemics and patients were more prominent in the gifted students than in the ordinary students. Upper-grade students exhibited improved attitudes compared with middle-grade students. Furthermore, emotions exerted no moderating effects on the relationship between moral cognition and epidemic-related attitudes among the gifted elementary students. On the basis of the findings, this study proposes the following recommendations: 1. In the context of the COVID-19 pandemic, individuals may experience slight mood changes due to psychological adjustment to the new normal. In the present study, the students had different perspectives of COVID-19 and thus experienced different emotions. Future studies may investigate the suitable approach and time point for evaluating emotions. The relationship between moral attitudes and behaviors remains to be clarified in an actual classroom setting. Qualitative studies may be conducted to investigate this relationship. 2. In terms of moral cognition and attitudes toward the pandemic and patients, middle-grade gifted students appear to experience more negative emotions than do others;this may pose a considerable psychological burden on them. Thus, teachers must provide psychological support and counseling to gifted students with different needs and teach them to actively process and analyze situational information to help them devise strategies for stress relief. 3. Enhancing the belief and positive expectation of students regarding social issues may help improve their attitudes toward moral issues, thus improving their ethical behaviors.
ABSTRACT
Many companies are utilizing social media as the primary avenue for customer service during the pandemic. However, how customers' behaviors and interactions with customer service agents on social media are impacted by the lockdowns has not been well understood. In this study, we examine the impact of lockdowns and physical distancing on changes in customers' behaviors, such as emotional expressions in tweets and customers' satisfaction with social media customer service. Using a difference-in-differences research design, we find that with the lockdowns and physical distancing, customers expressed more negative emotions when tweeting the company they were having issues with. Surprisingly, compared to before the pandemic period, customers' emotional expressions became more positive and they were more likely to express their satisfaction after interacting with customer service agents. Interestingly, our findings reveal that gender differences exist in these scenarios. We also discuss the theoretical and practical implications of these findings. © 2023 IEEE Computer Society. All rights reserved.
ABSTRACT
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.
ABSTRACT
Objective To understand the status of COVID-19 vaccination among elderly adults in long-term care facilities and analyze the influencing factors so as to provide scientific basis for improving the policy of COVID-19 vaccination. Methods The socio-demographic characteristics, disease-related data, disability, and COVID-19 vaccination status of 575 elderly adults who resided in long-term care facilities in Shaanxi Province were collected via Sojumpin in January 2022. Factors that affected non-vaccinated elderly adults were analyzed by using the SPSS 25.0 software. Results Of the included 575 participants, 199 (34. 6%) were not vaccinated against COVID-19. Univariate analysis showed that COVID-19 vaccination was associated with age, room type, length of stay, marital status, number of children, chronic diseases (i.e., diabetes, stroke, dementia), disability degree, and long-term medication use. Logistic regression analysis demonstrated that age of 90 years or above (OR =4. 25), triple room (OR = 6.17), moderate disability (OR = 2. 94), severe disability (OR =6. 67), long-term medication use (OR = 1.81), and stroke (OR =1. 74) were independent risk factors for not injecting COVID-19 vaccine. Conclusion The COVID-19 vaccination coverage rate of elderly adults in long-term care facilities needs to be improved, and more attention should be paid to the high-risk groups (e.g., who are older, and have disability, long-term medication use, or stroke).Copyright © 2023 Xi'an Medical University. All rights reserved.
ABSTRACT
SARS-CoV-2 continues to accumulate mutations to evade immunity, leading to breakthrough infections after vaccination. How researchers can anticipate the evolutionary trajectory of the virus in advance in the design of next-generation vaccines requires investigation. Here, we performed a comprehensive study of 11,650,487 SARS-CoV-2 sequences, which revealed that the SARS-CoV-2 spike (S) protein evolved not randomly but into directional paths of either high infectivity plus low immune resistance or low infectivity plus high immune resistance. The viral infectivity and immune resistance of variants are generally incompatible, except for limited variants such as Beta and Kappa. The Omicron variant has the highest immune resistance but showed high infectivity in only one of the tested cell lines. To provide cross-clade immunity against variants that undergo diverse evolutionary pathways, we designed a new pan-vaccine antigen (Span). Span was designed by analyzing the homology of 2675 SARS-CoV-2 S protein sequences from the NCBI database before the Delta variant emerged. The refined Span protein harbors high-frequency residues at given positions that reflect cross-clade generality in sequence evolution. Compared with a prototype wild-type (Swt) vaccine, which, when administered to mice, induced serum with decreased neutralization activity against emerging variants, Span vaccination of mice elicited broad immunity to a wide range of variants, including those that emerged after our design. Moreover, vaccinating mice with a heterologous Span booster conferred complete protection against lethal infection with the Omicron variant. Our results highlight the importance and feasibility of a universal vaccine to fight against SARS-CoV-2 antigenic drift.
ABSTRACT
Under the circumstance of COVID-19 epidemic spread, global medical resources are in serious shortage. As a common way of care for respiratory diseases, although back-slap sputum excretion can be used for the care of lung diseases, but it requires the cooperation of multiple medical staff, and lead to inefficient care. This paper designed a method of the human' s back feature recognition based on YOLOv5, and built a new type of intelligent robot for back-slap sputum excretion on this basis, which can assist care staff to complete the back-slap sputum excretion care for patients, and reduce the labor intensity of staff and the risk of cross infection. © 2022 IEEE.
ABSTRACT
The aim of this study was to explore the effects of the moral cognition of gifted elementary schools students on their attitudes toward COVID-19. The study further investigated the changes in their emotions during the pandemic and the moderating effects of their emotions on the relationship between their moral cognition and attitudes toward patients with COVID-19. Various factors influence the moral cognition of children, such as age, sex, intelligence level, and personality. Moreover, their surrounding environments, particularly home and school environments, strongly affect their moral cognition. Therefore, various studies have explored relevant factors, such as education level, role replacement, peer relationship, family economic status, family structure, family emotion, religious belief, and sociocultural background. Nevertheless, the question regarding the attitudes of gifted children with outstanding potential toward moral issues should be explored. Lovecky (1997) indicated that gifted children are highly concerned about moral issues since childhood and that they have an excellent understanding of moral issues. Compared with their peers with a relatively low level of intelligence, gifted children have an improved understanding of fairness, justice, and responsibility toward he self and others (Gross, 1993), and this thus engenders high levels of moral sensitivity (Piechowski, 1991). Therefore, the question of whether the levels of these students' moral perceptions vary depending on grade, sex, or sociocultural identity warrants exploration. Gifted students differ from others intellectually, socially, emotionally, and physically;however, their ability to cognitively understand moral issues is higher than their ability to emotionally adjust to such issues (Clark, 2002/2007). Accordingly, they need opportunities to discuss moral issues around them and promote their moral growth (Lovecky, 1997). Epidemics exert strong negative effects on the general public;this fact invoked curiosity in the research fraternity regarding the effects of epidemics on gifted students belonging to different grades, sexes, and sociocultural identities. Questions arose regarding the effects of emotions on the moral perceptions of gifted students and whether such effects further affect the students' moral behaviors and attitudes. Studies on moral education in gifted students have not reported any major outcomes;this might be because of the lack of an association between moral cognition and moral practice (Liu, 2002). From an educational perspective, studies have explored the efforts of schools in educating children and constructing their moral cognition;gifted students perform better in making ethical choices than do other students. The COVID-19 may be the first real-life pandemic situation experienced by young students. Therefore, students must receive information related to health and epidemic prevention. The question of whether the attitudes of gifted and ordinary elementary school students vary depending on various factors (grade, sex, and sociocultural identity) in a real setting must be explored. Moreover, whether cognition and attitude are related remains to be determined. Whether the levels of students' moral cognition can help predict their attitudes toward epidemics and diseases also warrants clarification. Accordingly, on the basis of the theory of moral cognition development in children, the present study investigated the current status of moral cognition levels, emotions, and attitudes toward epidemics and patients in gifted and ordinary students and compared the findings between the two cohorts. The study findings may serve as a reference for designing ethics courses for gifted students with special needs in order to cultivate their sense of social responsibility and civic awareness and cultivate the virtues of knowing, loving, and doing good. This study included a total of 887 elementary school students (gifted, 515;ordinary, 372). Three research tools — the Behavior Defining Questions Test, Epidemic and Patien Attitude Scale, and Emotion Scale — were used for data collection and analysis. The results revealed no significant differences between gifted and ordinary students in terms of moral cognitive performance. Regarding the epidemic-related emotions of students belonging to various grades and sexes, this study determined that the ordinary students expressed higher levels of belief, fear, surprise, and sadness than did the gifted students;middle-and higher-grade gifted students expressed fear, surprise, sadness, and disgust;and boys expressed higher levels of sadness than did girls. The levels of moral attitudes toward epidemics and patients were more prominent in the gifted students than in the ordinary students. Upper-grade students exhibited improved attitudes compared with middle-grade students. Furthermore, emotions exerted no moderating effects on the relationship between moral cognition and epidemic-related attitudes among the gifted elementary students. On the basis of the findings, this study proposes the following recommendations: 1. In the context of the COVID-19 pandemic, individuals may experience slight mood changes due to psychological adjustment to the new normal. In the present study, the students had different perspectives of COVID-19 and thus experienced different emotions. Future studies may investigate the suitable approach and time point for evaluating emotions. The relationship between moral attitudes and behaviors remains to be clarified in an actual classroom setting. Qualitative studies may be conducted to investigate this relationship. 2. In terms of moral cognition and attitudes toward the pandemic and patients, middle-grade gifted students appear to experience more negative emotions than do others;this may pose a considerable psychological burden on them. Thus, teachers must provide psychological support and counseling to gifted students with different needs and teach them to actively process and analyze situational information to help them devise strategies for stress relief. 3. Enhancing the belief and positive expectation of students regarding social issues may help improve their attitudes toward moral issues, thus improving their ethical behaviors. © 2022, National Taiwan Normal University. All rights reserved.
ABSTRACT
Objective: To analyze the epidemiological characteristics and transmission chain of an epidemic of COVID-19 in Haidian district, Beijing. Methods: Descriptive epidemiological method was used to analyze the epidemiological characteristics of the epidemic, and field investigation and big data technology were used to analyze the transmission chain of the epidemic. Results: From April 27 to May 13, 2022, an epidemic of COVID-19 occurred in Haidian district. The strains isolated from the cases were identified by whole genome sequencing as Omicron variant (BA.2.2 evolutionary branch). A total of 38 infection cases were detected, including 34 confirmed cases and 4 asymptomatic cases. Most cases were mild ones (88.2%), no severe, critical or death cases occurred. The early clinical symptoms were mainly sore throat (50.0%) and cough (29.4%). The epidemic lasted for 17 days, resulting in 7 generations of the cases and involving 3 community transmissions, 2 working place transmissions and 8 family transmissions; the main infection routes were co-residence (47.6%) and co-space exposure (31.6%). The intergenerational interval M(Q1, Q3)was 3 (1, 6) days. The overall secondary attack rate was 1.5% (37/2 482), and the family secondary attack rate was 36.7% (18/49). Conclusions: The cases in this COVID-19 epidemic caused by Omicron variant had mild clinical symptoms, but the case clustering in families and communities was obvious, the transmission was rapid, and the risk for co-space exposure was high. It is necessary to use information technology to identify close contacts in the local population for the rapid and effective blocking of the epidemic spread.
Subject(s)
COVID-19 , Epidemics , Humans , COVID-19/epidemiology , Beijing/epidemiology , SARS-CoV-2ABSTRACT
The application of machine learning classification algorithms to COVID-19 for CT images assisted diagnosis not only reduces the workload of radiologists in reviewing films, but also improves the accuracy and efficiency of the assisted diagnosis results. However the instability of such machine learning models may lead to misclassification of results, and the expected output of the models may not be available due to the lack of transparency, which make the obtaining of test oracle difficultly. Thus in this paper, the metamorphic testing technique is applied to test the intelligent diagnosis classification program of COVID-19. The metamorphic relation is constructed by analyzing the characteristics of the lesion areas in the CT images of COVID-19, and compare consistency of the follow up test cases with the original test cases, that is how the failure detection rate of the program can be verified. The experimental results show that this method can detect the inconsistency of this program and it can be extended to test intelligent diagnosis classification programs of different diseases, thus further improving the accuracy of diagnosis classification programs. © 2022 IEEE.
ABSTRACT
OBJECTIVE To find out whether 2811 will cause toxic reactions in animals, and determine the safe dose of without any toxic reactions and the relationship between the dose, time of administration and results of the toxicity test. METHODS Thirty healthy rhesus monkeys were selected and randomly divided into 3 groups, 1 O in each group (half males and half females), namely, the solvent control group, 2811 100 and 400 mg* kg-1 groups, respectively. The solvent control group was iv given 0.9% sodium chloride injection, while the experimental groups were iv given 2811 100 and 400 mg* kg-1 , respectively, once every 6 days, 3 times in 2 weeks, and allowed to recover for 9 weeks after drug withdrawal. During the test, the body weight, food intakes, body temperatures, ophthalmology, blood pressure, electrocardiograms, blood routine, anticoagulation, blood biochemistry, electrolytes, urine, systemic anatomy, organ weight and coefficient were observed, while histopathology and immunology tests were performed. At the same time, the anti-drug antibody (ADA) and plasma concentrations were determined, and toxikinetic parameters were analyzed. RESULTS During the experiment, the observation of general symptoms, body mass, food intakes, body temperatures, ophthalmology, blood pressure, electrocardiograms, blood routine, anticoagulation, blood biochemistry, electrolytes, urine, organ weight and coefficient, histopathology and immunology of animals in each dose group showed no significant changes related to the tested animals. ADA was not detected in any of the groups. Plasma drug concentrations in 2B11 100 and 400 mg* kg-1 groups were basically consistent and proportional to the dose, so was the ratio of peak concentration and exposure. 2B11 injection showed linear kinetics in vivo. CONCLUSION Under the conditions set in this test, the 2-week repeated administration toxicity test of 2B11 in rhesus monkeys is safe, and no clinical adverse reactions are observed at the dose level of 400 mg*kg-1, which provides reference for the follow-up clinical study of 2B11. Copyright © 2022 Chinese Journal of Pharmacology and Toxicology. All rights reserved.
ABSTRACT
Ruili and Longchuan, two border counties in southwestern China, are facing epidemic control challenges due to the high rate of COVID-19 infections originating from neighboring Myanmar. Here, we aimed to establish the applicability of wastewater and environmental water surveillance of SARS-CoV-2 and conduct whole-genome sequencing (WGS) to trace the possible infection origin. In August 2021, total 72 wastewater and river water samples were collected from 32 sampling sites. SARS-CoV-2 ORF1ab and N genes were measured by RT-qPCR. We found that 19 samples (26.39%) were positive, and the viral loads of ORF1ab and N genes were 6.62 × 102–2.55×105 and 1.86 × 103–2.32 × 105 copies/L, respectively. WGS further indicated the sequences in two transboundary river samples, and one hospital wastewater sample belonged to the delta variant, suggesting that the infection source might be areas with high COVID-19 delta variant incidence in Southeast Asia (e.g., Myanmar). We reported for the first time the detection and quantification of SARS-CoV-2 RNA in the transboundary rivers of Myanmar–China. Our findings demonstrate that wastewater and environmental water may provide independent and nonintrusive surveillance points to monitor the global spread of emerging COVID-19 variants of concern, particularly in high-risk regions or border areas with considerable epidemic challenges and poor wastewater treatment facilities.
ABSTRACT
Ankit Srivastava et al. [1] proposed a parallel framework for Constraint-Based Bayesian Network (BN) Learning via Markov Blanket Discovery (referred to as ramBLe) and implemented it over three existing BN learning algorithms, namely, GS, IAMB and Inter-IAMB. As part of the Student Cluster Competition at SC21, we reproduce the computational efficiency of ramBLe on our assigned Oracle cluster. The cluster has 4x36 cores in total with 100 Gbps RoCE v2 support and is equipped with Centos-compatible Oracle Linux. Our experiments, covering the same three algorithms of ramBLe, evaluate its strong and weak scalability of the algorithms using real COVID-19 data sets. We verify part of the conclusions in the paper and propose our explanation of the differences. IEEE
ABSTRACT
Financial markets are widely believed to be complex systems where interdependencies exist among individual entities in the system enabling the risk spillover effect. The detrended cross-correlation analysis (DCCA) has found wide applications in examining the comovement of fluctuations among financial time series. However, to what extent can such cross-correlation represent the spillover effect is still unknown. This article constructs the DCCA network of commodity future markets and explores its proximity to the volatility spillover network. Results show a moderate agreement between the two networks. Centrality measures applied to the DCCA networks are able to identify key commodity futures that are transmitting or receiving risk spillovers. The evolution of the DCCA network reveals a significant change in the network structure during the COVID-19 pandemic in comparison to that of the pre- and post-pandemic periods. The pandemic made the commodity future markets more interconnected leading to a shorter diameter for the network. The intensified connections happen mostly between commodities from different categories. Accordingly, cross-category risk spillovers are more likely to happen during the pandemic. The analysis enriches the applications of the DCCA approach and provides useful insights into understanding the risk dynamics in commodity future markets.
ABSTRACT
A portable and low-cost electrochemical immunosensor platform is developed for rapid (13 min) and accurate quantification of SARS-CoV-2 serum antibodies (10.1 ng/mL − 60 µg/mL for IgG and 1.64 ng/mL − 50 µg/mL for IgM). No obvious cross-reactivity with other interference proteins was observed. Stable performance of the immunosensor within 24-week storage at room temperature was achieved. The practical use of the immunosensor was demonstrated using real patient samples. © 2021 MicroTAS 2021 - 25th International Conference on Miniaturized Systems for Chemistry and Life Sciences. All rights reserved.
ABSTRACT
Pandemic respiratory viral pathogens like Influenza A and SARS COV2 exhibit continuous and evasive mutations in cell surface molecules, making vaccination with the goal of antibody-mediated protection elusive. CD8 T cells mediate eradication of viral disease, and vaccination to conserved internal viral proteins to elicit CD8 T cell memory is a promising strategy. Using a mouse model, we compared pulmonary infection with H1N1 influenza with skin (epidermal) vaccination using Modified Vaccinia Ankara (MVA) expressing highly conserved NP or another conserved Ags. H1N1 influenza pulmonary infection led to recruitment and lung infiltration with Ag specific CD8 T cells by day 5-10. By day 40, abundant CD8 lung TRM and LN TCM were present. Surprisingly, by day 80, both lung TRM and systemic TCM cells were greatly diminished and were absent at day 120. These mice were protected against lethal challenge at day 40 but not day 80, suggesting built-in obsolescence of CD8 memory. In contrast, epidermal vaccination led to CD8 T cell infiltration of lung at day 5-10, measurable at day 40 and still detectable at day 80 in lung, LN and spleen. In addition, a novel intravascular lung population of CD8 T cells was present at all time points. These mice were completely protected against lethal flu challenge at day 80 and 120. Protection was observed after pulmonary challenge with either H1N1 or H3N2 influenza as well as in B cell depleted mice. We analyzed protective immunity in skin vaccinated mice. At 2 hours after pulmonary challenge, Ag specific CD8 T cells moved from the intravascular space into the lung parenchyma, were abundant at day 3 and persisted for >80 days. Single cell RNA sequencing indicated that these intravascular T cells were transcriptionally distinct from systemic TEM and TCM. We conclude that CD8 T cell immunity after pulmonary infection is powerful but short-lived, while skin vaccine induced CD8 T cell protective immunity is mediated by lung intravascular T cells is protective and durable.