Review on two-dimensional material-based field-effect transistor biosensors: accomplishments, mechanisms, and perspectives.

Field-effect transistor (FET) is regarded as the most promising candidate for the next-generation biosensor, benefiting from the advantages of label-free, easy operation, low cost, easy integration, and direct detection of biomarkers in liquid environments. With the burgeoning advances in nanotechnology and biotechnology, researchers are trying to improve the sensitivity of FET biosensors and broaden their application scenarios from multiple strategies. In order to enable researchers to understand and apply FET biosensors deeply, focusing on the multidisciplinary technical details, the iteration and evolution of FET biosensors are reviewed from exploring the sensing mechanism in detecting biomolecules (research direction 1), the response signal type (research direction 2), the sensing performance optimization (research direction 3), and the integration strategy (research direction 4). Aiming at each research direction, forward perspectives and dialectical evaluations are summarized to enlighten rewarding investigations.

Longitudinal association between problematic smartphone use and sleep disorder among Chinese college students during the COVID-19 pandemic.

BACKGROUND: Problematic smartphone use (PSU) and sleep disorders (SD) are common public health problems among college students. While previous cross-sectional studies have found a relationship between PSU and SD, the causal direction of this relationship remains unclear. This study aims to examine the longitudinal changes of PSU and SD during the COVID-19 pandemic, determine the causal relationship between them, and identify confounding factors that affect this association. METHODS: The study sample consisted of 1186 Chinese college students (47.7% male) with a mean age of 18.08 years. Participants completed the Smartphone Addiction Scale - Short Version (SAS-SV) and the Pittsburgh Sleep Quality Index (PSQI) at both baseline and follow-up surveys, conducted one year apart. The cross-lagged panel model (CLPM) was used to examine the causal relationship between PSU and SD, stratified by gender and duration of daily physical activity. The fixed effect panel regression was used to confirm the findings of CLPM. RESULTS: The results of the CLPM analysis showed a significant bidirectional relationship between PSU and SD for the overall sample, which was consistent with the fixed effects model findings. However, subgroup analyses revealed that the bidirectional association disappeared among males or those who engaged in daily physical activity for more than 1 h. CONCLUSIONS: Our study shows a significant bidirectional association between PSU and SD, with variations across gender and daily physical activity levels. Encouraging physical activity may serve as a potential intervention to disrupt the bidirectional association between PSU and SD, which has important implications for public health strategies aimed at reducing the negative consequences of PSU and SD.

International student perceptions of online medical education during the COVID-19 epidemic.

This study aimed to investigate how international students enrolled on medical and surgical bachelor's degree programs (MBBS) in China perceived online medical education course, compared to native Chinese students during the Covid-19 pandemic. The perceptions of 38 MBBS and 31 Chinese sophomores were surveyed using the Chaoxing platform. The international student group's mean satisfaction with online teaching was 2.737 on a 5-point scale, much lower than the Chinese students' mean score of 4.355 (p < 0.05). Similarly, the international students expressed less satisfaction than the Chinese learners with other aspects of the course, including the teacher's level, at 3.964 ± 0.818 versus 4.445 ± 0.548 (p < 0.05); curriculum organization, at 3.651 ± 0.848 versus 4.333 ± 0.568 (p < 0.05); and self-learning level, at 3.634 ± 0.996 versus 3.686 ± 0.949 (p > 0.05), respectively. There were also noteworthy differences between the progress made by the international students in Chinese language learning, which was positively correlated with satisfaction with teaching on the online medical education (p < 0.05). The results suggest that, while online teaching was a necessary response to the Covid-19 pandemic, satisfaction with this mode of education is lower among international students than their Chinese counterparts.

UK trade in the time of COVID-19: A review.

This paper offers a detailed review of the UK's trade performance during the COVID-19 crisis and reflects on how this may be revived. During 2020, UK goods exports contracted more sharply than those of its international peers. Statistics suggest that UK had a deeper decline and slower recovery than Germany, Italy, Spain and the US. Further, the trends from 2017 to 2019 show a weakening in the UK's global competitiveness, suggesting a more persistent development against the backdrop of productivity slowdown and Brexit uncertainty. We analyse the confluence of internal and external factors that impact on UK trade and emphasise the importance of boosting productivity in the recovery from the COVID crisis and Brexit.

Antibodies Can Last for More Than 1 Year After SARS-CoV-2 Infection: A Follow-Up Study From Survivors of COVID-19.

Background: COVID-19 is a global pandemic. The prevention of SARS-CoV-2 infection and the rehabilitation of survivors are currently the most urgent tasks. However, after patients with COVID-19 are discharged from the hospital, how long the antibodies persist, whether the lung lesions can be completely absorbed, and whether cardiopulmonary abnormalities exist remain unclear. Methods: A total of 56 COVID-19 survivors were followed up for 12 months, with examinations including serum virus-specific antibodies, chest CT, and cardiopulmonary exercise testing. Results: The IgG titer of the COVID-19 survivors decreased gradually, especially in the first 6 months after discharge. At 6 and 12 months after discharge, the IgG titer decreased by 68.9 and 86.0%, respectively. The IgG titer in patients with severe disease was higher than that in patients with non-severe disease at each time point, but the difference did not reach statistical significance. Among the patients, 11.8% were IgG negative up to 12 months after discharge. Chest CT scans showed that at 3 and 10 months after discharge, the lung opacity had decreased by 91.9 and 95.5%, respectively, as compared with that at admission. 10 months after discharge, 12.5% of the patients had an opacity percentage >1%, and 18.8% of patients had pulmonary fibrosis (38.5% in the severe group and 5.3% in the non-severe group, P < 0.001). Cardiopulmonary exercise testing showed that 22.9% of patients had FEV1/FVC%Pred <92%, 17.1% of patients had FEV1%Pred <80%, 20.0% of patients had a VO2 AT <14 mlO2/kg/min, and 22.9% of patients had a VE/VCO2 slope >30%. Conclusions: IgG antibodies in most patients with COVID-19 can last for at least 12 months after discharge. The IgG titers decreased significantly in the first 6 months and remained stable in the following 6 months. The lung lesions of most patients with COVID-19 can be absorbed without sequelae, and a few patients in severe condition are more likely to develop pulmonary fibrosis. Approximately one-fifth of the patients had cardiopulmonary dysfunction 6 months after discharge.

Similarities and differences between multiple inflammatory syndrome in children associated with COVID-19 and Kawasaki disease: clinical presentations, diagnosis, and treatment.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been spreading rapidly around the world, while "multisystem inflammatory syndrome in children" (MIS-C) is a new type of syndrome that has now been reported in many countries. Similar and different characteristics between KD and MIS-C have been reported in a variety of literature. We aimed to focus on reviewing clinical presentations, diagnosis, and treatment of KD and MIS-C. METHODS: We searched articles in the electronic databases, including the Cochrane Library database, EMBASE, and MEDLINE with the keywords "multiple inflammatory syndrome" and/or "COVID-19" and/or "Kawasaki disease" and "children". RESULTS: Main presentations of MIS-C and KD include fever, rashes, mucous membrane involvement, conjunctivitis, hands and feet erythema/edema, and cervical lymphadenopathy. However, compared with the highest incidence of KD among some Asian countries, MIS-C is common among Black and Hispanic children. MIS-C is common in older children and teenagers, whereas classic KD is common in children under five years of age. Gastrointestinal symptoms, shock, and coagulopathy are common in MIS-C patients but are not common in classic KD. Cardiac manifestations are more common than KD, including myocarditis with cardiac dysfunction and coronary artery dilation or aneurysms. Severe cases in MIS-C present with vasodilated or cardiogenic shock that requires fluid resuscitation, muscular support, and even mechanical ventilation and extracorporeal membrane oxygenation (ECMO), whereas KD rarely presents with these manifestations and requires these treatments. Increased serum ferritin, leukopenia, lymphopenia and thrombocytopenia are common in MIS-C. However, thrombocytosis is a characteristic feature of KD. Intravenous immunoglobulin (IVIG) and moderate-high dose aspirin are still a standard recommended treatment for KD. In addition to the above-mentioned medications, steroids and biological drugs are frequently used in patients with MIS-C. Most of the children with KD have a good prognosis; however, the long-term clinical outcomes of MIS-C are not clear. CONCLUSIONS: The overall presentation and treatment of MIS-C appear to overlap with KD. However, there are still great differences between the syndromes, and it is controversial to say whether MIS-C is a new entity or is a "severe type" of KD.

Bank Loans for Small Businesses in Times of COVID-19: Evidence from China

Using representative loan-level data in China, this paper shows that bank loans for small businesses are more generous and flexible during the pandemic. In places more severely affected by the pandemic, loans for small businesses have lower costs, shorter maturities, larger amounts, are more likely to be unsecured loans. Small businesses are also more likely to extend the loan repayment, while the probability of defaulting shows no significant differences. Although the easy monetary policies implemented by central banks help small business financing, the government should pay attention to the potential NPL concerns in the post-pandemic periods.

[Strategies for infection control in managing critically ill patients with suspected coronavirus disease 2019 in non-designated hospital].

The management of healthcare services for the suspected cases in non-designated hospitalsis a serious concern in controlling coronavirus disease 2019 (COVID-19) epidemic. Owing to the complexity of care providers, large requirement of medical supplies as well as the possible needs off frequent transfers, the major difficulty is preventing the coronavirus from spreading while caring the suspected critical cases before the 2019 novel coronavirus ribonucleic acid test results are reported. For the purpose of enhancing the prevention of the propagation of COVID-19, this article puts emphasis on the following aspects in non-designated hospital Peking University Third Hospital: preparatory procedures of receiving critical suspected patients, the management of medical personnel during the waiting session of RNA test results, the delivering procedures of testing samples, the management of referred medical wastes, daily operations including the cleaning and sanitizing of caring units and the management of related patients after the testing session.

Pixatimod (PG545), a clinical-stage heparan sulfate mimetic, is a potent inhibitor of the SARS-CoV-2 virus (preprint)

A major global effort is currently ongoing to search for therapeutics and vaccines to treat or prevent infection by the SARS-CoV-2 virus. Repurposing existing entities is one attractive approach. The heparan sulfate mimetic pixatimod is a clinical-stage synthetic sulfated compound that is a potent inhibitor of the glycosidase heparanase, and has known anti-cancer, anti-inflammatory and also antiviral properties. Here we show that pixatimod binds directly to the SARS-CoV-2 spike protein S1 receptor binding domain (RBD) and alters its conformation. Notably, this site overlaps with the known ACE2 binding site in the S1 RBD. We find that pixatimod inhibits binding of recombinant S1 RBD to Vero cells which express the ACE2 receptor. Moreover, in assays with three different isolates of live SARS-CoV-2 virus we show that pixatimod effectively inhibits viral infection of Vero cells. Importantly, its potency is well within its safe therapeutic dose range. These data provide evidence that pixatimod is a potent antiviral agent against SARS-CoV-2. Together with its other known activities this provides a strong rationale for its clinical investigation as a new multimodal therapeutic for the current COVID-19 pandemic.

A Novel Combination of Vitamin C, Curcumin and Glycyrrhizic Acid Potentially Regulates Immune and Inflammatory Response Associated with Coronavirus Infections: A Perspective from System Biology Analysis.

Novel coronaviruses (CoV) have emerged periodically around the world in recent years. The recurrent spreading of CoVs imposes an ongoing threat to global health and the economy. Since no specific therapy for these CoVs is available, any beneficial approach (including nutritional and dietary approach) is worth investigation. Based on recent advances in nutrients and phytonutrients research, a novel combination of vitamin C, curcumin and glycyrrhizic acid (VCG Plus) was developed that has potential against CoV infection. System biology tools were applied to explore the potential of VCG Plus in modulating targets and pathways relevant to immune and inflammation responses. Gene target acquisition, gene ontology and Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment were conducted consecutively along with network analysis. The results show that VCG Plus can act on 88 hub targets which are closely connected and associated with immune and inflammatory responses. Specifically, VCG Plus has the potential to regulate innate immune response by acting on NOD-like and Toll-like signaling pathways to promote interferons production, activate and balance T-cells, and regulate the inflammatory response by inhibiting PI3K/AKT, NF-κB and MAPK signaling pathways. All these biological processes and pathways have been well documented in CoV infections studies. Therefore, our findings suggest that VCG Plus may be helpful in regulating immune response to combat CoV infections and inhibit excessive inflammatory responses to prevent the onset of cytokine storm. However, further in vitro and in vivo experiments are warranted to validate the current findings with system biology tools. Our current approach provides a new strategy in predicting formulation rationale when developing new dietary supplements.