A bibliometric analysis of the trends, topics, and findings of research publications on asynchronous and synchronous online language learning over three decades

Since the first study on computer-mediated communication tools in support of language learning was published in 1992, asynchronous and synchronous tools have been widely adopted;however, few reviews have been conducted to explore the research status in this field. As COVID-19 has increased the use of online tools in education, the need to understand how asynchronous and synchronous tools are being used in language education has grown. In this bibliometric analysis, we reviewed asynchronous and synchronous online language learning (ASOLL) by analyzing the trends, topics, and findings of 319 articles on ASOLL. The results indicate that interest in ASOLL has increased over the past three decades with ASOLL for oral proficiency development and collaborative ASOLL being the two main research issues. Interest in three topics collaborative ASOLL, emotions, and corrective feedback - was especially apparent. The review contributes to the understanding of ASOLL while providing practical implications for using information communication technologies to enhance language learning.

Textual Research on Key Information of Ancient Classical Prescription Dayuanyin.

Dayuanyin,a representative prescription for the treatment of dampness pathogen lodging in pleurodiaphragmatic interspace syndrome,was first recorded in Treatise on Pestilence(<<>>)by Wu Youke in the Ming Dynasty for dealing with pestilence,and it still plays an important role in the treatment of coronavirus disease 2019(COVID-19)differentiated into dampness stagnating in lung syndrome. The related original ancient records were retrieved from the Chinese Classics of Traditional Chinese Medicine(Version 5.0),Full-text Database of Ancient Chinese Medicine Books,and Ancient Books of Traditional Chinese Medicine Database (http://www. gydc. ac. cn:81/),with 'Dayuanyin' and 'Dayuansan' as the search terms,followed by statistical analysis and textual research. The composition,dosage,processing of original medicinal materials,efficacy, indications, processing and administration methods, modern basic research, and clinical applications of Dayuanyin were summarized,so as to provide literature reference for its modern development and clinical application. The findings demonstrated that the composition in most medical records was identical with that of the original prescription,except that some records concerning Angelicae Dahuricae Radix and Tsaoko Fructus differed. In terms of dosage,it did not change much,with the only difference observed in Tsaoko Fructus. The processing methods of medicinal materials in Dayuanyin were not specified in historical records,so the raw medicinal materials were recommended. The processing and administration methods in the original record were basically followed in the later generations,except that some medical records chose Zingiberis Rhizoma Recens as the guide and changed the decocting amount and administration time. In terms of efficacy and indications, Dayuanyin was originally developed for dispelling pathogenic Qi away from the pleurodiaphragmatic interspace, but later employed for the treatment of such diseases as 'pestilence','epidemic malaria',and 'seasonal epidemic'. It was mainly indicated to 'epidemic diseases' with latent pathogen in pleurodiaphragmatic interspace as the pathogenesis and fever as the manifestation. In modern clinical application,ancients physicians considered 'fever' and 'powder-like tongue coating' as the important signs for this prescription. Modern physicians have utilized Dayuanyin for treating fever,diseases in the digestive,respiratory,urinary,and endocrine systems,skin diseases,pediatric diseases,as well as epidemic diseases like influenza,severe acute respiratory syndrome (SARS),and avian flu due to its good effects.Copyright © 2021, China Academy of Chinese Medical Sciences Institute of Chinese Materia Medica. All rights reserved.

Expert consensus on diagnosis and treatment of adult mental stress-induced hypertension in China (2022 Revision): Part B

Mental stress has been recognized as an essential risk factor for hypertension. Therefore, experts specializing in cardiology, psychiatry, and Traditional Chinese Medicine organized by the Psycho-cardiology Group, College of Cardiovascular Physicians of Chinese Medical Doctor Association, and Hypertension Group of the Chinese Society of Cardiology proposed the expert consensus on the diagnosis and treatment of adult mental stress-induced hypertension in March 2021, which includes the epidemiology, etiology, diagnosis, and treatment of the mental stress-induced hypertension. This consensus will hopefully facilitate the clinical practice of this disorder. In addition, the COVID-19 pandemic has become one of the primary global sources of psychosocial stressors since the beginning of 2020, and the revision of this expert consensus in 2022 has increased the relevant content. This consensus consists of two parts. The sections of Part A include (I) Background and epidemiological characteristics, (II) Pathogenesis, and (III) Diagnosis. The sections of Part B contain (IV) Treatment recommendations, and (V) Prospects. This article presents Part B of the consensus. © 2022 Heart and Mind ;Published by Wolters Kluwer - Medknow.

Expert consensus on diagnosis and treatment of adult mental stress induced hypertension in China (2022 revision): Part A

Mental stress has been recognized as an essential risk factor for hypertension. Therefore, experts specializing in cardiology, psychiatry, and Traditional Chinese Medicine organized by the Psycho-Cardiology Group of College of Cardiovascular Physicians of Chinese Medical Doctor Association and Hypertension Group of Chinese Society of Cardiology proposed the expert consensus on the diagnosis and treatment of adult mental stress-induced hypertension in March 2021, which includes the epidemiology, etiology, diagnosis, and treatment of the mental stress-induced hypertension. This consensus will hopefully facilitate the clinical practice of this disorder. In addition, the COVID-19 pandemic has become one of the primary global sources of psychosocial stressors since the beginning of 2020, and the revision of this expert consensus in 2022 has increased the relevant content. This consensus consists of Part A and Part B. Part A includes (I) Background and epidemiological characteristics, (II) Pathogenesis, and (III) Diagnosis and Part B includes (IV) Treatment recommendations and (V) Prospects. This part presents the content of Part A. © 2022 Heart and Mind ;Published by Wolters Kluwer - Medknow.

Textual Research on Key Information of Ancient Classical Prescription Dayuanyin.

Dayuanyin,a representative prescription for the treatment of dampness pathogen lodging in pleurodiaphragmatic interspace syndrome,was first recorded in Treatise on Pestilence(<<>>)by Wu Youke in the Ming Dynasty for dealing with pestilence,and it still plays an important role in the treatment of coronavirus disease 2019(COVID-19)differentiated into dampness stagnating in lung syndrome. The related original ancient records were retrieved from the Chinese Classics of Traditional Chinese Medicine(Version 5.0),Full-text Database of Ancient Chinese Medicine Books,and Ancient Books of Traditional Chinese Medicine Database (http://www. gydc. ac. cn:81/),with 'Dayuanyin' and 'Dayuansan' as the search terms,followed by statistical analysis and textual research. The composition,dosage,processing of original medicinal materials,efficacy, indications, processing and administration methods, modern basic research, and clinical applications of Dayuanyin were summarized,so as to provide literature reference for its modern development and clinical application. The findings demonstrated that the composition in most medical records was identical with that of the original prescription,except that some records concerning Angelicae Dahuricae Radix and Tsaoko Fructus differed. In terms of dosage,it did not change much,with the only difference observed in Tsaoko Fructus. The processing methods of medicinal materials in Dayuanyin were not specified in historical records,so the raw medicinal materials were recommended. The processing and administration methods in the original record were basically followed in the later generations,except that some medical records chose Zingiberis Rhizoma Recens as the guide and changed the decocting amount and administration time. In terms of efficacy and indications, Dayuanyin was originally developed for dispelling pathogenic Qi away from the pleurodiaphragmatic interspace, but later employed for the treatment of such diseases as 'pestilence','epidemic malaria',and 'seasonal epidemic'. It was mainly indicated to 'epidemic diseases' with latent pathogen in pleurodiaphragmatic interspace as the pathogenesis and fever as the manifestation. In modern clinical application,ancients physicians considered 'fever' and 'powder-like tongue coating' as the important signs for this prescription. Modern physicians have utilized Dayuanyin for treating fever,diseases in the digestive,respiratory,urinary,and endocrine systems,skin diseases,pediatric diseases,as well as epidemic diseases like influenza,severe acute respiratory syndrome (SARS),and avian flu due to its good effects.Copyright © 2021, China Academy of Chinese Medical Sciences Institute of Chinese Materia Medica. All rights reserved.

A Dynamic Access Control Model Based on Attributes and Intro VAE

Affected by the COVID-19 pandemic, teleworking is becoming more popular, with the exposed attack surface of the internal network expanding. Once outsiders personate accounts or insiders conduct illegal operations, the data security in teleworking with traditional border protection will be broken. Therefore, it is necessary to implement fine-grained and dynamic access control to protect data from malicious access. Attribute-based access control (ABAC) is ideal, where authorization is performed through attributes and rules. On this basis, risk assessment, context awareness, and machine learning are supplemented for dynamic access control. However, these methods have their limitations due to the requirement of sufficient prior knowledge and massive label-classified data. Moreover, it is challenging to obtain the samples of attack behaviors, and the attack behaviors may change frequently to evade detection. In contrast, the normal behaviors are relatively stable except for the update of network services. We propose a dynamic access control model, ABAC-IntroVAE, to address the above issues. ABAC-IntroVAE judges users' requests through rule matching and behavior analysis based on the attributes of the requests. It first filters out requests against the rules by rule matching. Then, the introspective variational autoencoder (IntroVAE) is used for behavior analysis to realize dynamic access decisions. Requests classified as normal can be authorized for access. ABAC-IntroVAE only needs samples of normal requests for training, avoiding the difficult task of collecting massive and frequently changing samples of attack requests. Meanwhile, the IntroVAE model is updated through continual learning to adapt to new-style normal behaviors due to the update of network services. Our experiment study suggests that our proposed ABAC-IntroVAE can effectively perform dynamic access control. It achieves an accuracy of 97.2% in abnormal detection and maintains an accuracy of over 97% through continual learning, despite the addition of new-style user behavior patterns. © 2022 IEEE.

Online learning research in the era of COVID-19: Bibliometric analysis and topic modeling

The global rampancy of COVID-19 has caused profound changes in education sectors. Perhaps the most salient change is the shift of the instructional paradigm from face-to-face instruction to fully online learning. To address the challenges facing the education sector, researchers and educational practitioners have extensively investigated the transition in teaching mode under COVID-19, with a growing contribution to a range of topics in relation to online learning. Against this backdrop, it is necessary to gain a comprehensive understanding of the major hotspots and issues of online learning so as to develop appropriate and effective policies on strategic (re-)allocation of resources to more critical initiatives. This study aims to adopt bibliometrics and topic modeling to identify prominent research topics on online learning under COVID-19 from the large-scale, unstructured text of research publications. Specifically, structural topic modeling will be used to identify predominant topics concerned by scholars working in the field of online learning research. The non-parametrical Mann-Kendell trend test will also be applied to uncover the developmental tendency of each identified topic. In addition, the correlations among the key topics will be revealed and visualized by hierarchical clustering analysis. Based on the analytical results, suggestions will be made to facilitate educational policy formulation to promote the development and effective implementation of technological, scientific, and pedagogical activities of online learning. © 2022 IEEE.

Neoadjuvant multimodality RX including immunotherapy for highly selective unresectable locally advanced esophageal squamous cell carcinoma (NEXUS): A prospective, single-arm, phase II trial

Background: This study aimed to evaluate the efficacy and safety of preoperative PD-1 inhibitor tislelizumab combined with CRT in unresectable esophageal squamous cell carcinoma (ESCC). Method(s): This is a single-arm, phase II trial, planned to enroll 30 patients. Eligibility criteria include histologically confirmed unresectable thoracic ESCC stage at cT4bNxM0 (AJCC 8th). Radiotherapy was delivered to a total dose of 50Gy/25f, concurrently with cisplatin (25 mg/m2) and nab-paclitaxel (100 mg) (QW, at least 3 cycles). Then followed by two cycles of tislelizumab (200 mg, Q3W), cisplatin (75 mg/m2, Q3W) and nab-paclitaxel (150 mg/m2, Q3W). If curative resection was considered, esophagectomy was performed within 4 weeks. Patients with pathologically residual disease would receive tislelizumab (200 mg, Q3W) for 1 year. The primary endpoint is 1-year progression free survival rate. Result(s): From December 2021 to July 2022, 21 patients were enrolled. 16 patients completed chemoradiotherapy and received immunochemotherapy. Reasons for 5 patients who did not receive immunochemotherapy included patient refusal (n=1), progressive disease (n=1), esophageal fistula (n=2), waiting for immunochemotherapy (n=1). Finally, 13 patients proceeded to surgery, with R0 resection rate of 100%. Reasons for not undergoing surgery after immunochemotherapy were esophageal mediastinal fistula (n=1), surgery delay due to COVID-19 epidemic (n=2). The pCR and MPR rate was 61.5% (8/13) and 76.9% (10/13). G1, G2, G3 immune related pneumonia occurred in 3 patients, respectively. >=G3 AEs occurred in 9 (42.9%) patients. Postoperative complications included anastomotic fistula (2/13), pleural effusion (2/13), pneumonia (1/13), myocardial damage (1/13), delayed wound healing (1/13). Conclusion(s): Chemoradiotherapy followed by immunochemotherapy might be a useful conversional treatment option for unresectable ESCC. Esophagectomy after this could be safe with acceptable complications for unresectable locally advanced ESCC. Clinical trial identification: ChiCTR2100054327. Legal entity responsible for the study: The authors. Funding(s): Has not received any funding. Disclosure: All authors have declared no conflicts of interest. Copyright © 2022 European Society for Medical Oncology

Safety of inactivated SARS-CoV2 vaccines in liver transplantation recipients

Objectives: To evaluate the safety of inactivated SARS-CoV2 vaccines in liver transplantation recipients. Materials and Methods: This is a cross-sectional observational study. We enrolled stable liver transplantation recipients who had completed the full course of the covid-19 vaccines in our hospital from March 2021 to October 2021. The general adverse reactions and severe adverse events following immunization reported in the LT group were compared to those reported in the general population receiving inactivated covid-19 vaccine. Results: We recruited 151 eligible LT recipients, among which 120 (79.5%) were males, and 31(20.5%) were female. The median age was 56.0 (49.0, 63.0) years old. The median period after LT was 8.44 (4.37, 12.39) years, the median trough concentration of tacrolimus was 2.5 (1.8, 3.9) ng/L. 83 (58.9%) subjects received the CoronaVac vaccine (Sinovac Biotech Ltd), the remaining received Sinopharm Covid-19 vaccine (Beijing Institute of Biological), or compound course of CoronaVac and Sinopharm. The reported incidence of general adverse reaction among LT recipients in the current study was 15.9%, as compared with the reported incidence of 41.7%-46.5% in the general population (Fig. 1A). The prevalence of pain at the injection site, fatigue, headache, pruritus was 9.9%, 5.2%, 1.3%, 0.7% respectively, as compared with the reported 19.4%-27.9%), 10.6-11.2%, 12.6%-13.1%, 1.3%-1.5% in the general population (Fig. 1B). Both inactivated vaccines had similar incidence of adverse reactions. No LT recipients had vaccine related SAE or Covid-19 infection during follow-up despite being residing in areas that had local outbreaks (Beijing, Yunnan, Henan). Conclusion: Covid-19 vaccine was safe in LT recipients. Only a few participants experienced mild reactions such as pain at the injection site and fatigue. (Figure Presented).

Operator Perception of the Ability of Multiple Single-Use Bronchoscopes to Engage Difficult Airway Segments

Introduction: The COVID-19 pandemic has increased the prevalence of single-use bronchoscopes outside the operating room, where they had previously been employed primarily as intubation adjuncts. However, direct comparisons of the performance of these bronchoscopes has been limited. In this study, we describe our initial experience studying operator perception of how well multiple different bronchoscopes are able to engage difficult airway segments in an ex-vivo model. Methods: Nine faculty and fellows from the Pulmonary and Critical Care Division at UCSD were recruited to complete an airway survey of an ex-vivo model using three single use bronchoscopes (Olympus H-SteriScope, Ambu A-Scope 4, Verathon GlideScope B-Flex). This survey included engagement into traditionally difficult airway segments (RB1, RB6, LB1/2 and LB6) with and without a tool in the working channel. Immediately after completing these bronchoscopies, participants were directed to complete an anonymous survey rating each bronchoscopes ease of maneuverability into the difficult segments on a scale of 1-100 with a higher number representing a more favorable rating. The participant's ability to successfully engage each of these segments was also recorded. Results: Participants rated the ability to maneuver into difficult airway segments with a tool in the working channel by the Olympus singleuse bronchoscope (97.2 [94.3-100]) and Ambu single-use bronchoscope (84.7[74.2-95.2]) higher than the GlideScope single-use bronchoscope (49.3[36.3-64.3]) (Table 1). Additionally, a greater number of participants were able to successfully engage the selected difficult airway segments using the Olympus and Ambu single-use bronchoscopes both with and without a tool in the working channel when compared to the GlideScope single-use bronchoscope (Table 2 and Table 3). Conclusions: In this singlecenter study, the Olympus H-SteriScope and Ambu A-Scope 4 single-use bronchoscopes had a higher perceived maneuverability and were better able to engage difficult airway segments than the GlideScope B-Flex single-use bronchoscope. Further studies are needed to compare these single-use bronchoscopes to reusable bronchoscopes.

Dynamical analysis for the impact of asymptomatic infective and infection delay on disease transmission

The influence of asymptomatic patients on disease transmission has attracted more and more attention, but the mechanism of some factors affecting disease transmission needs to be studied urgently. Considering the self-healing rate of asymptomatic patients, the cure rate of symptomatic patients, the transformation rate from asymptomatic to symptomatic and the infection delay, a type of infectious disease dynamics model SIsIaS with asymptomatic infection and infection delay is established in this paper. It is found that both the infection delay and the difference size between the cure rate and the self-healing rate not only affect the minimum value of the total number of patients in the persistent state of the disease, but also lead to disease extinction to be controlled by the proportion of symptomatic patients in patients. Moreover, the infection delay can lead to local Hopf bifurcation of periodic solutions. By using the normal form and center manifold theory the direction of Hopf bifurcations and the stability of bifurcated periodic solutions are discussed. At last, sensitivity analysis shows that the infection delay can change the correlation of the proportion of symptomatic patients in patients and the transformation rate to the total number of patients. (C) 2022 International Association for Mathematics and Computers in Simulation (IMACS). Published by Elsevier B.V. All rights reserved.

On the Test Accuracy and Effective Control of the COVID-19 Pandemic: A Case Study in Singapore

This study examines the impact of coronavirus disease 2019 (COVTD-19) test accuracy (i.e., sensitivity and specificity) on the progression of the pandemic under two scenarios of limited and unlimited test capacity. We extend the classic susceptible-exposed-infectious-recovered model to incorporate test accuracy and compare the progression of the pandemic under various sensitivities and specificities. We find that high-sensitivity tests effectively reduce the total number of infections only with sufficient testing capacity. Nevertheless, with limited test capacity and a relatively high cross-infection rate, the total number of infected cases may increase when sensitivity is above a certain threshold. Despite the potential for higher sensitivity tests to identify more infected individuals, more false positive cases occur, which wastes limited testing capacity, slowing down the detection of infected cases. Our findings reveal that improving test sensitivity alone does not always lead to effective pandemic control, indicating that policymakers should balance the trade-off between high sensitivity and high false positive rates when designing containment measures for infectious diseases, such as COVID-19, particularly when navigating limited test capacity.

The battle between host and SARS-CoV-2: Innate immunity and viral evasion strategies

The SARS-CoV-2 virus, the pathogen causing COVID-19, has caused more than 200 million confirmed cases, resulting in more than 4.5 million deaths worldwide by the end of August, 2021. Upon detection of SARS-CoV-2 infection by pattern recognition receptors (PRRs), multiple signaling cascades are activated, which ultimately leads to innate immune response such as induction of type I and III interferons, as well as other antiviral genes that together restrict viral spread by suppressing different steps of the viral life cycle. Our understanding of the contribution of the innate immune system in recognizing and subsequently initiating a host response to an invasion of SARS-CoV-2 has been rapidly expanding from 2020. Simultaneously, SARSCoV-2 has evolved multiple immune evasion strategies to escape from host immune surveillance for successful replication. In this review, we will address the current knowledge of innate immunity in the context of SARS-CoV-2 infection and highlight recent advances in the understanding of the mechanisms by which SARS-CoV-2 evades a host's innate defense system.

Thromboembolism in COVID -19 patients on ECMO

Venous thromboembolism (VTE) is a common complication of COVID-19 (coronavirus disease 2019), which often leads to sudden deterioration and death. There are multiple mechanisms contributing to this phenomenon. Endothelial injury from COVID-19 triggers platelet activation and adhesion, leucocyte aggregation, cytokine storm and complement activation. Cytokine storm triggers coagulation activation and thrombin generation. Complement activation is also thought to trigger the formation of systemic thrombus through recruiting inflammatory cytokines and possible complement-mediated thrombotic microangiopathy. Patients on extracorporeal membrane oxygenation (ECMO) are at risk of developing thromboembolism. Thrombus formation within the extracorporeal circuit is the main reason for systemic thromboembolism. Possibly that by contacting blood and nonendothelial surfaces, ECMO triggers activation of coagulation pathway and inflammatory response. Thromboembolic prophylaxis is critical in managing COVID-19 patients on ECMO. Anticoagulation is recommended to all hospitalised COVID-19 patients unless there are contraindications. However, patients are still found to develop VTE while on anticoagulation and the prevalence of VTE in COVID-19 patients on ECMO is still unclear. We aim to investigate the VTE incidence and contribute to anticoagulation strategy and management in this specific population. We retrospectively reviewed the data of 23 patients who were diagnosed with COVID-19 and managed with ECMO. All patients received thromboembolic prophylaxis since admission. We report our findings of the incidences of thromboembolism. Twenty-three adult patients who were diagnosed with COVID-19 received ECMO support. Sixteen patients were minorities, and seven patients were Caucasians. The mean age of patients was 44.8-year old. Seventeen patients were males, and 11 patients had at least one of the following pre-ECMO comorbidity: ten (43.5%) patients had hypertension, 11 (47.8%) patients had type 2 diabetes and four (17.3%) patients had hyperlipidaemia. None of the patients were active smokers or had chronic lung disease. During the hospital course, all patients received heparin for thromboembolic prophylaxis. The overall VTE rate was 34.7%. Six patients developed deep vein thrombosis (DVT) (26%) with lower extremities induration. Two patients were found to have pulmonary embolism (PE) (8.7%). Four patients had clotted circuit that requiring exchange. No stroke or myocardial infarction (MI) was diagnosed in these patients. Heparin-induced thrombocytopenia (HIT) was excluded in all cases. Based on our study, the overall VTE rate of COVID-19 patients on ECMO was 34.7% with 26% incidence of DVT and 8.7% incidence of PE. According to Jenner's recent systemic review of 28 studies, 34% of 2928 ICU-managed COVID-19 patients developed VTE. PE was found in 12.6% of patients and DVT was detected in 16.1% of patients. 529 patients (18.0%) received ECMO in the cohort. When compared with our study, there were no statistically significant differences of the incidences of VTE, DVT or PE between these two studies, although all our patients were on ECMO support. Further investigation into the prevalence, implications and management of thromboembolism in COVID-19 patients on ECMO will lead to significantly improved outcomes for this specific patient population..

Respiratory Syncytial and Parainfluenza Virus Infection Increase the Risk of Cytomegalovirus Reactivation in Allogeneic Hematopoietic Cell Transplant Recipients

Background. Respiratory virus infections are associated with significant and specific local and systemic inflammatory response patterns, which may lead to reactivation of latent viruses. We examined whether viral upper (URTI) or lower respiratory tract infection (LRTI) with common respiratory viruses increased the risk of CMV viremia after allogeneic hematopoietic cell transplantation (HCT). Methods. We retrospectively analyzed patients undergoing allogeneic HCT between 4/2008 and 9/2018. CMV surveillance was performed weekly and the presence of upper and lower respiratory symptoms were evaluated by multiplex respiratory viral PCR. We used Cox proportional hazards models to evaluate risk factors for development of any CMV viremia or high level CMV viremia in the first 100 days post-HCT. Each respiratory virus infection episode was considered positive for 30 days beginning the day of diagnosis. Results. Among 2,545 patients (404 children, 2141 adults), 1,221 and 247 developed CMV viremia and high level CMV viremia, respectively, in the first 100 days post-HCT. Infections due to human rhinoviruses (HRV, N=476) were most frequent, followed by parainfluenza viruses 1-4 (PIV, N=139), seasonal human coronaviruses (COV, N=134), respiratory syncytial virus (RSV, N=77), influenza A/B (FLU, N=35), human metapneumovirus (MPV, N=37), and adenovirus (ADV, N=61). In adjusted models, RSV LRTI was associated with increased risk of developing CMV viremia at all levels (Figures 1 and 2), and PIV or RSV URTI increased the risk of high level CMV viremia;all other viruses showed no association in univariable models. Figure 1. Model estimates for associations between LRTI and development of any CMV viremia Figure 2. Model estimates for associations between LRTI and development of high level CMV viremia Conclusion. We demonstrated that RSV and PIV infections are associated with an increased risk for development of CMV viremia after allogeneic HCT. This novel association provides the rationale to explore virus-specific inflammatory pathways that may trigger CMV reactivation. CMV viremia may also serve as an endpoint in clinical trials that assess new preventative or therapeutic interventions of RSV or PIV infection.

Performance Evaluation of Travel Security System for Low-mobility Individuals Under the Epidemic

In order to guarantee travel service quality of low-mobility individuals under the public health emergency, this paper was set in the COVID-19, compared travel behavior characteristics of low-mobility individuals and general public between before and during the epidemic, defined evaluation indexes of travel security system for low-mobility individuals, built the performance evaluation model of travel security system for low-mobility individuals based on the matter element analysis. The results of travel behavior analysis find that the travel service quality of low-mobility individuals is necessary to get guarantee, because they have many travel difficulties during the epidemic. The results of performance evaluation verify that evaluation indexes and evaluation model are reasonable and effective. Research findings can be used as a reference for government departments to formulate travel security strategies under the public health emergency, and can provide practical guidance for the construction and performance evaluation of travel service security system for low-mobility individuals during the epidemic. © 2021, Editorial Department of Wuhan University of Technology. All right reserved.

Gene Sequence Representation Learning Based on Virus Transmission Network

There always exists non-coding and missing sequence in obtained gene sequence data. The existing gene sequence representation methods extract features from high dimension gene sequence mostly through manual process, which usually are computationally expensive. What's more, the precision of prediction heavily relies on how to utilize the biology background knowledge. In this work, we construct a gene sequence representation method based on graph context information in virus transmission network. After coding the target node's virus sequence, we use attention mechanism to aggregate the neighbor nodes' gene sequence information, and thus we can achieve a new representation of the target node's gene sequence. The gene sequence representation model is optimized based on the fact that the similarity of gene sequence of neighbor nodes is higher than that of non-neighbor nodes. The new representation after being well trained not only extracts the feature of sequence exactly, but also reduces the dimension of gene sequence greatly and improve the computation efficiency. We first train the gene sequence representation model respectively on a simulation transmission network, SARS-CoV-2 and HIV transmission network, and then predict the un-sampled infections in each transmission network. The experimental results show the effectiveness of our model, and its performance is better than other models. What's more, its success on effectively predicting the un-sampled infections in virus transmission network has a certain practical significance in the epidemiological investigation area. © 2021, Science Press. All right reserved.

A multi-modal approach to life-threatening hemoptysis in a patient with covid-19 ards

Introduction: Life-threatening hemoptysis is rare in patients diagnosed with COVID-19. Here, we describe a severe case of hemoptysis a patient with COVID-19 and the multi-modal approach to manage this condition. Case: A 57 year-old man with diabetes was admitted with hypoxemic respiratory failure due to COVID-19 pneumonia. Despite treatment with convalescent plasma, remdesivir and dexamethasone, he developed progressive respiratory failure eventually requiring VVECMO support on hospital day 8. He was started on heparin for therapeutic anticoagulation at this time. Anticoagulation was held on day 23 after large blood clots were suctioned via tracheostomy tube. CT revealed complete opacification of the bilateral lungs and major airways without evidence of acute arterial blushing (panel A). The patient underwent the first in a series of therapeutic bronchoscopies via a size 10 Shiley tracheostomy tube on day 28. Occlusive gelatinous blood clots were noted immediately upon entering the trachea. After failure of adequate clot evaluation with cryoprobe, a modified 24F chest tube was used as a suction catheter to achieve clot removal. After visualizing major airways, a bronchial blocker was positioned in the bronchus intermedius. Topical tranexamic acid was applied to sites of bleeding in the left upper lobe. Repeat bronchoscopy was performed on day 30, which showed new bleeding in the left lower lobe segments. An endobronchial blocker was repositioned in the left lower lobe and Surgicel was applied to ongoing bleeding sites within the right and left lung. Prior to repeat bronchoscopy, the patient was administered inhaled tranexamic acid three times daily due to findings of severely inflamed mucosa and diffused nature of bleed. On day 32, bronchoscopy revealed significantly improved bleeding. In-line suctioning was held in favor of daily diagnostic bronchoscopies to avoid suction trauma. Ultimately, the patient's bleeding resolved and he was eventually liberated from both ECMO and the ventilator with corresponding improvement on CT imaging (panel B). Discussion: We describe a case of a life-threatening hemoptysis in a patient with COVID-19 ARDS who was successfully managed using serial therapeutic bronchoscopies employing cryotherapy, mechanical tamponade, and pharamacologic coagulants to achieve hemostasis.