A privacy-preserving blockchain-based tracing model for virus-infected people in cloud

The outbreak of COVID-19 has exposed the privacy of positive patients to the public, which will lead to violations of users' rights and even threaten their lives. A privacy-preserving scheme involving virus-infected positive patients is proposed by us. The traditional ciphertext policy attribute-based encryption (CP-ABE) has the features of enhanced plaintext security and fine-grained access control. However, the encryption process requires the high computational performance of the device, which puts a high strain on resource-limited devices. After semi-honest users successfully decrypt the data, they will get the real private data, which will cause serious privacy leakage problems. Traditional cloud-based data management architectures are extremely vulnerable in the face of various cyberattacks. To address the above challenges, a verifiable ABE scheme based on blockchain and local differential privacy is proposed, using LDP to perturb the original data locally to a certain extent to resist collusion attacks, outsourcing encryption and decryption to corresponding service providers to reduce the pressure on mobile terminals, and deploying smart contracts in combination with blockchain for fair execution by all parties to solve the problem of returning wrong search results in a semi-honest cloud server. Detailed security proofs are performed through the defined security goals, which shows that the proposed scheme is indeed privacy-protective. The experimental results show that the scheme is optimized in terms of data accuracy, computational overhead, storage performance, and fairness. In terms of efficiency, it greatly reduces the local load, enhances personal privacy protection, and has high practicality as well as reliability. As far as we know, it is the first case of applying the combination of LDP technology and blockchain to a tracing system, which not only mitigates poisoning attacks on user data, but also improves the accuracy of the data, thus making it easier to identify infected contacts and making a useful contribution to health prevention and control efforts. © 2022 Elsevier Ltd

Knowledge integration for resilience among multinational SMEs amid the COVID-19: from the view of global digital platforms

Purpose: Multinational small-to-medium-sized enterprises (SMEs) are increasingly participating in cross-border digital platforms – especially amid the COVID-19 pandemic. Accordingly, knowledge integration (KI) has become more and more important. In fact, it has been deemed by many as the key to organizational resilience. Given this burgeoning phenomenon, this study aims to explore a path for improving the resilience of multinational SMEs. Through this process, this study also finds a relationship between the KI processes associated with adopting global digital platforms and the resiliency of local–global businesses. Hence, in part, this paper also explores the effectiveness of all these mechanisms. Design/methodology/approach: This study used the stepwise regression method in Stata 16.0 to analyze the direct effects of both horizontal and vertical KI processes on the resilience of local–global businesses. Additionally, t-tests were also used to compare the differences in coefficients between the mechanisms. The sample analyzed comprised data on multinational manufacturing SMEs in the Yangtze River Delta region of China who are using global digital platforms. Findings: The KI processes of these firms, both horizontal and vertical, positively correlate to resilience. Horizontal KI processes more efficiently increase the resilience of global businesses, whereas vertical processes more efficiently increase the resilience of local businesses. Originality/value: First, this study provides insights into how multinational SMEs can improve their resilience in a crisis. In addition to adding to the knowledge of KI processes, this expands the KM literature on pandemics. Second, by creating two KI processes based on global digital platforms and discussing their influence on resilience, this research deepens the understanding of affordance in the KM literature. Third, focusing on the KI research stream, the results shed light on how KI processes might occur and how firms develop their KI processes. © 2022, Emerald Publishing Limited.

Evaluation of at-home methods for N95 filtering facepiece respirator decontamination.

N95 filtering facepiece respirators (FFRs) are essential for the protection of healthcare professionals and other high-risk groups against Coronavirus Disease of 2019 (COVID-19). In response to shortages in FFRs during the ongoing COVID-19 pandemic, the Food and Drug Administration issued an Emergency Use Authorization permitting FFR decontamination and reuse. However, although industrial decontamination services are available at some large institutions, FFR decontamination is not widely accessible. To be effective, FFR decontamination must (1) inactivate the virus; (2) preserve FFR integrity, specifically fit and filtering capability; and (3) be non-toxic and safe. Here we identify and test at-home heat-based methods for FFR decontamination that meet these requirements using common household appliances. Our results identify potential protocols for simple and accessible FFR decontamination, while also highlighting unsuitable methods that may jeopardize FFR integrity.

[Analysis on the efficacy and safety of fibrinolytic therapy in patients with acute ST-segment elevation myocardial infarction during the COVID-19 epidemic].

Objective: To evaluate the efficacy and safety of fibrinolysis strategy in patients with acute ST-segment elevation myocardial infarction (STEMI) during the COVID-19 epidemic, and to provide reference value for optimization of fibrinolytic process on the premise of prevention and control of COVID-19 transmission, including self-protection of medical staff. Methods: The efficacy and safety of fibrinolysis were retrospectively analyzed in 7 patients with acute STEM, who hospitalized from February 29, 2020 to April 3, 2020 in the Department of Cardiology, Wuhan Union Hospital of Tongji Medical College, Huazhong University of Science and Technology. To optimize the fibrinolytic process on the premise of prevention and control of COVID-19 transmission, including self-protection of medical staff, a full-time medical team in charge of fibrinolysis under third-grade protection was established. The acute STEMI patients were treated immediately in a fixed and isolated area in emergency department before receiving green channel fibrinolysis. Blood samples for complete blood count, COVID-19 antibody test and nasopharyngeal swab samples for COVID-19 nucleic acid test were made before fibrinolysis, while the chest CT examination was accomplished after fibrinolysis. By comparing differences of time from the first electrocardiogram (ECG) to fibrinolysis before and after the improvement of fibrinolytic process, the effect of optimization of the fibrinolytic process was evaluated. Results: In the present study, seven patients with acute STEMI received fibrinolysis therapy, 6 of them achieved reperfusion and no bleeding was observed in all of the patients. Five out of the 7 patients were hospitalized after fibrinolysis, and the hospitalization days were 19.6 days on average. By following up to April 14, 2020, none of the 7 patients died. The first 2 patients were treated according to the routine medical procedure and the time from the first ECG to fibrinolysis were 201 and 106 minutes, respectively. After the optimization of the fibrinolytic process, the time from the first ECG to fibrinolysis of the last 5 patients were 42, 46, 51, 43 and 54 minutes, respectively，which was significantly shorter than that before optimization. Conclusions: During the COVID-19 epidemic, fibrinolysis in patients with acute STEMI is safe, effective and easy to implement. Therefore, it is recommended as the top priority for the patients with acute STEMI with indications for fibrinolysis. On the premise of prevention and control of COVID-19 transmission, including self-protection of medical staff, the duration of myocardial ischemia can be shortened by optimization of the fibrinolytic process.

[Analysis of bronchoscope-guided tracheal intubation in 12 cases with coronavirus disease 2019 under the personal protective equipment with positive pressure protective hood].

Endotracheal intubation is an independent risk factor for respiratory infectious diseases. We conducted a retrospective study in 12 cases with COVID-19 who underwent endotracheal intubation at ICU of the Guangzhou eighth hospital from January 20 to February 10, 2020. The intubation procedure, anesthetic regimen, and complication were collected and analyzed. The 9 healthcare workers who involved in intubation received virus nucleic acid test and 14 days temperature monitoring. All 12 patients were successfully intubated under the guidance of bronchoscope, without any complications. Midazolam, Propofol and Morphine or fentanyl were used for sedation and analgesia, avoiding patients cough and agitated during the procedure. The 9 healthcare workers were protected under the Personal Protective Equipment(PPE) with positive pressure protective hood. The detection of oropharyngeal swab virus nucleic acid were negative in all 9 healthcare workers, none of them had fever or any respiratory symptoms. The PPE with positive pressure protective hood should be needed to perform bronchoscope-guided endotracheal intubation in patients with COVID-19, it could strengthen to protect healthcare workers from virus exposure.

[Clinical feature changes of a COVID-19 patient from mild to critical condition and cardiopulmonary pathological results].

Objective: To analyse the clinical history, laboratory tests and pathological data of a patient who suffered from novel coronavirus pneumonia(COVID-19) and provide reference for the clinical treatment of similar cases. Methods: Data of clinical manifestation, laboratory examination, bronchoscopy, echocardiography and cardiopulmonary pathological results were retrospectively reviewed in a case of COVID-19 with rapid exacerbation from mild to critical condition. Results: This patient hospitalized at day 9 post 2019 novel coronavirus(2019-nCoV) infection, experienced progressive deterioration from mild to severe at day 12, severe to critical at day 18 and underwent extracorporeal membrane oxygenation(ECMO) and continuous renal replacement therapy(CRRT) as well as heart lung transplantation during day 28-45 post infection, and died at the second day post heart and lung transplantation. The patient had suffered from hypertension for 8 years. At the early stage of the disease, his symptoms were mild and the inflammatory indices increased and the lymphocyte count decreased continuously. The patient's condition exacerbated rapidly with multi-organ infections, and eventually developed pulmonary hemorrhage and consolidation, pulmonary hypertension, right heart failure, malignant ventricular arrhythmias, liver dysfunction, etc. His clinical manifestations could not be improved despite viral RNAs test results became negative. The patient underwent lung and heart transplantation and finally died of multi organ failure at the second day post lung and heart transplantation. Pathological examination indicated massive mucus, dark red secretions and blood clots in bronchus. The pathological changes were mainly diffused pulmonary hemorrhagic injuries and necrosis, fibrosis, small vessel disease with cardiac edema and lymphocyte infiltration. Conclusions: The clinical course of severe COVID-19 can exacerbate rapidly from mild to critical with lung, liver and heart injuries.

An update on the status of COVID-19: a comprehensive review.

The last two decades have witnessed two large-scale pandemics caused by coronaviruses, including severe acute respiratory syndrome (SARS) and the Middle East respiratory syndrome (MERS). At the end of 2019, another novel coronavirus, designated as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), hit Wuhan, a city in the center of China, and subsequently spread rapidly to the whole world. Latest reports revealed that more than 800 thousand people in over 200 countries are involved in the epidemic disease by SARS-CoV-2. Due to the high mortality rate and the lack of optimum therapeutics, it is crucial to understand the biological characteristics of the virus and its possible pathogenesis to respond to the SARS-CoV-2. Rapid diagnostics and effective therapeutics are also important interventions for the management of infection control. However, the rapid evolution of SARS-CoV-2 exerted tremendous challenges on its diagnostics and therapeutics. Therefore, there is an urgent need to summarize the existing research results to guide decision-making on the prioritization of resources for research and development. In this review, we focus on our current understanding of epidemiology, pathogenesis, diagnostics and therapeutics of coronavirus disease 2019 (COVID-19).