Synthesis of Y zeolite via acid-catalyzed hydrolysis of tetraethylorthosilicate (preprint)

The siliceous precursor was hydrolyzed from tetraethylsilicic acid (TEOS) under acidic conditions, then sodium aluminate and sodium hydroxide were added, and Y zeolite was obtained by hydrothermal crystallization under alkaline conditions. The key synthesis parameters, such as reactant molar ratios, crystallization temperature and time were changed to optimize the synthesis conditions. The obtained products were characterized by XRD, SEM, N2 adsorption and ICP elemental analysis. The well-crystallized Y zeolite was successfully synthesized by hydrolysis of TEOS catalyzed by sulfuric acid at low crystallization temperature 85℃ which has a SiO2/Al2O3 ratio（SAR）of 5.55.

2D Zn‐Porphyrin‐Based Co(II)‐MOF with 2‐Methylimidazole Sitting Axially on the Paddle–Wheel Units: An Efficient Electrochemiluminescence Bioassay for SARS‐CoV‐2

High electrocatalytic activity with tunable luminescence is crucial for the development of electrochemiluminescence (ECL) luminophores. In this study, a porphyrin‐based heterobimetallic 2D metal organic framework (MOF), [(ZnTCPP)Co2(MeIm)] (1), is successfully self‐assembled from the zinc(II) tetrakis(4‐carboxyphenyl)porphine (ZnTCPP) linker and cobalt(II) ions in the presence of 2‐methylimidazole (MeIm) by a facile one‐pot reaction in methanol at room temperature. On the basis of the experimental results and the theoretical calculations, the MOF 1 contains paddle–wheel [Co2(‐CO2)4] secondary building units (SBUs) axially coordinated by a MeIm ligand, which is very beneficial to the electron transfer between the Co(II) ions and oxygen. Combining the photosensitizers ZnTCPP and the electroactive [Co2(‐CO2)4] SBUs, the 2D MOF 1 possesses an excellent ECL performance, and can be used as a novel ECL probe for rapid nonamplified detection of the RdRp gene of SARS‐CoV‐2 with an extremely low limit of detection (≈30 aM). A novel porphyrin‐based heterobimetallic 2D MOF, [(ZnTCPP)Co2(MeIm)] (1) is constructed to act as an excellent electrochemiluminescence probe for rapid nonamplified detection of SARS‐CoV‐2.

Deep‐Learning‐Assisted Noncontact Gesture‐Recognition System for Touchless Human‐Machine Interfaces

Human‐machine interfaces (HMIs) play important role in the communication between humans and robots. Touchless HMIs with high hand dexterity and hygiene hold great promise in medical applications, especially during the pandemic of coronavirus disease 2019 (COVID‐19) to reduce the spread of virus. However, current touchless HMIs are mainly restricted by limited types of gesture recognition, the requirement of wearing accessories, complex sensing platforms, light conditions, and low recognition accuracy, obstructing their practical applications. Here, an intelligent noncontact gesture‐recognition system is presented through the integration of a triboelectric touchless sensor (TTS) and deep learning technology. Combined with a deep‐learning‐based multilayer perceptron neural network, the TTS can recognize 16 different types of gestures with a high average accuracy of 96.5%. The intelligent noncontact gesture‐recognition system is further applied to control a robot for collecting throat swabs in a noncontact mode. Compared with present touchless HMIs, the proposed system can recognize diverse complex gestures by utilizing charges naturally carried on human fingers without the need of wearing accessories, complicated device structures, adequate light conditions, and achieves high recognition accuracy. This system could provide exciting opportunities to develop a new generation of touchless medical equipment, as well as touchless public facilities, smart robots, virtual reality, metaverse, etc. [ FROM AUTHOR] Copyright of Advanced Functional Materials is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Proteomic analysis of human milk reveals nutritional and immune benefits in the colostrum from mothers with COVID-19 (preprint)

The range of benefits breastfeeding provides neonates and infants include nutrition, improved neonatal survival, and reduced morbidity from certain diseases. It also aids maternal health by speeding postpartum recovery. However, due to concern about the risk of SARS-CoV-2 transmission and the lack of evidence of breastmilk's protective effects against the virus, whether mothers with COVID-19 should be encouraged to breastfeed is under debate. Here, we present the results of proteomic and glycoproteomic studies of breast milk (colostrum and mature milk) from mothers with confirmed COVID-19. All colostrum samples exhibited significantly upregulated immune-related proteins, especially whey proteins with antiviral properties against SARS-CoV-2, and increased glycosylation levels and heterogeneity at those proteins. Such adaptive differences in milk from COVID-19 mothers tend to fade in mature milk from the same mothers one month postpartum. These results suggest the immune benefits of colostrum from mothers with COVID-19 and provide molecular-level insights that aid breastmilk feeding decisions in cases of active infection.

Transmission of SARS-CoV-2 Indoor and Outdoor Environments

Since the outbreak in late December 2019, the coronavirus disease 2019 (COVID-19) pandemic has spread across the globe, causing great damage to human life and property. A lot of researchers around the world have devoted themselves to the study of its origin, pathogenic mechanism, and transmission route, and this article gives a summary. First, both humans and animals can act as the host of coronavirus. In indoor environments, the virus may exist in aerosols, droplets, saliva, etc., from the nose and mouth connected to the respiratory system, as well as feces, urine, etc., from the digestive and urinary systems. In addition, other substances, such as breast milk, eye feces, and blood, released from the host can carry viruses. The virus transmitted indoors is affected by indoor machinery, natural forces, and human activities, and spreads in different distances. Second, the virus spreads outdoors through three kinds of media: solid, liquid, and gas, and is affected by their survival time, the temperature, and humidity in the environment.

School adaptation and behavior of the first batch of college students returning to school during the COVID-19 epidemic

Objective: To analyze the school adaptation and behavioral performance of the first batch of students who return to school during the COVID-19 epidemic, and to provide a theoretical basis for further development of corresponding intervention measures.

Alterations of Oropharyngeal Microbiome Reflected Disease Severity and Long-Term Dysbiosis in Patients With COVID-19 (preprint)

Background: Recent evidences have shown that gut microbiome of patients with COVID-19 significantly changes and can reflect the severity of the disease. And gut microbiota richness was not restored to normal levels after 6-month recovery. However, SARS-CoV-2 primarily infects the respiratory tract, few studies investigate whether the alterations of oropharyngeal microbiome is associated with disease severity in patients with COVID-19, and whether interferences in microbiome composition, if any, eliminate with clearance of the SARS-CoV-2 virus. We employed metatranscriptomic sequencing to analyse oropharyngeal swabs collected within a week of diagnosis COVID-19 (period of disease group: PDG) and two months after clearance of the SARS-CoV-2 virus (convalescent group: CG) from 47 patients with COVID-19. Meanwhile, oropharyngeal swabs from 40 healthy subjects were analyzed as healthy control group (HCG). Results: Oropharyngeal microbial composition was significantly altered in patients with COVID-19 compared with healthy controls even two months after clearance of the SARS-CoV-2 virus. Little changes in α-diversity among HCG, PDG and CG ( P ＞0.05), but obviously changes in β-diversity among them. Notably, Prevotella increased significantly in PDG than that in HCG (Wilcoxon rank-sum test, P ＜0.001) and increased gradually along with the severity of patients with COVID-19 aggravated. There was a positive correlation between Prevotella and the elevation of Neutrophil percentage (R = 0.301, P = 0.040). Similarly, SARS-CoV-2 and Aspergillus increased remarkably in critical Patients with COVID-19. There was a negative correlation between SARS-CoV-2 viral load and platelet counts (R = −0.330, P = 0.022). Conclusions: The oropharyngeal microbiome in patients with COVID-19 present persistent dysbiosis even two months after clearance of the SARS-CoV-2 virus. Furthermore, alterations in oropharyngeal microbial composition reflected the severity of disease in patients with COVID-19. Our findings underscore that there is an urgent need to understand the specific roles of oropharyngeal microorganisms in COVID-19 disease progression and rehabilitation.

First Quarter Chronicle of COVID-19: An Attempt to Measure Governments’ Responses

The crisis caused by the outbreak of COVID-19 revealed the global unpreparedness for handling the impact of a pandemic. In this paper, we present a first quarter chronicle of COVID-19 in Hubei China, Italy and Spain, particularly focusing on infection speed, death and fatality rates. By analysing the parameters of the best fitting distributions of the available data for the three rates in each of the three regions, we illustrate the pandemic’s evolution in relation to government measures. We compared the effectiveness of lockdown measures by observing the true situation in each dataset, without proposing a mathematical model. The feasibility of obtaining a firm conclusion in regard to the best solution for containing COVID-19 is limited, with a universal solution failing to exist due to globally varying culture, mentality and behaviours. Our method provides valid insights into the individual and national actions implemented and adhered to in order to slow the effect of the pandemic during the first-wave of COVID-19.

Cancer Patient Management Strategy in a Cancer Center of Zhejiang, China During the COVID-19 Pandemic (preprint)

Background: Due to the increased risk of viral infection and the severe shortage of medical resources during the pandemic of COVID-19, most hospitals in the epidemic areas significantly reduced non-emergency admissions and services, if not closed. As a result, it has been difficult to treat cancer patients on time, which adversely affects their prognosis. To address this problem, cancer centers must develop a strategic plan to manage both inpatients and outpatients during the pandemic, provide them with the necessary treatment, and at the same time prevent the spread of the virus among patients, visitors and medical staff. Methods: : Based upon the epidemic situation in Zhejiang Province, China, the number of running non-emergency medical wards in the Zhejiang Cancer Hospital was gradually increased in a controlled manner. All staff of the hospital received COVID-19 preventive training and was provided with three different levels of protection according to the risks of their services. Only patients without a known history of SARS-CoV-2 contact were eligible to schedule an appointment. Body temperature was measured on all patients upon their arrival at the hospital. Chest CT image, blood cell counting and travel/contact history were investigated in patients with fever. Respiratory tract samples, such as sputum and throat swabs, from all patients, including those clinically suspected of SARS-CoV-2 infection, were collected for nucleic acid detection of SARS-CoV-2 before treatment. Results: : A total of 3697 inpatients and 416 outpatients seeking cancer treatment were enrolled from February 1 to April 3, 2020, in compliance with the hospital’s infection-control interventions. The clinicopathological parameters of the patients were summarized herein. 4237 samples from 4101 patients produced negative RNA testing results. Four clinically suspected patients all presented negative RNA test results and were excluded from the SARS-CoV-2 infection through follow-up retesting and monitoring. Seven patients with only N-gene positive results were retested, followed by CT scan and SARS-CoV-2 contact history investigation. All of them were finally diagnosed as non-infected patients. There was one outpatient who was confirmed positive by virus RNA test and then followed up. She might be an asymptomatic laboratory-confirmed case. During the study period, there was no SARS-CoV-2 infection among staff, patients and escorts of patients in the Zhejiang Cancer Hospital. Conclusion: This study suggested our infection-control interventions, including viral nucleic acid test, could be used as a reliable method to screen cancer patients in the area with moderate COVID-19 prevalence. Cancer may not be a high-risk factor of SARS-CoV-2 infection.

Performance & Quality Evaluation of Marketed COVID-19 RNA Detection Kits (preprint)

Compared to other coronaviruses, COVID-19 has a longer incubation period and features asymptomatic infection at a high rate (>25%). Therefore, early detection of infection is the key to early isolation and treatment. Direct detection of the virus itself has advantages over indirect detection. Currently, the most sensitive and commercially validated method for COVID-19 testing is RT-qPCR, designed to detect amplified virus-specific RNA. Reliable testing has proven to be a bottleneck in early diagnosis of virus infection in all countries dealing with the pandemic. Significant performance and quality issues with available testing kits have caused confusion and serious health risks. In order to provide better understanding of the Quality and performance of COVID-19 RNA detection kits on the market, we designed a system to evaluate the specificity (quantitation), sensitivity (LOD) and robustness of the kits using positive RNA and pseudovirus controls based on COVID-19 genomic sequence. We evaluated 8 Nucleic Acid qPCR Kits approved in China, some of which are also approved in the US and EU. Our study showed that half of these 8 kits lack 1:1 linear relationship for virus RNA copy: qPCR signal. Of the 4 with linear response, 2 demonstrated sensitivity at 1 Copy viral RNA/Reaction, suitable for early detection of virus infection. Furthermore, we established the best RNA extraction, handling and qPCR procedures allowing highly sensitive and consistent performance using BGI qPCR kits. Our study provides an effective method to assess and compare performance quality of all COVID-19 nucleic acid testing kits, globally.

Countrywide quarantine only mildly increased anxiety level during COVID-19 outbreak in China (preprint)

In the recent outbreak of COVID-19, many countries have taken various kinds of quarantine measures to slow down the explosive spreading of COVID-19. Although these measures were proven to be successful in stopping the outbreak in China, the potential adverse effects of countrywide quarantine have not been thoroughly investigated. In this study, we performed an online survey to evaluate the psychological effects of quarantine in China using Zung Self-rating Anxiety Scale in February 2020 when the outbreak was nearly peaked in China. Along with the anxiety scores, limited personal information such as age, gender, region, education, occupation and specifically, the type and duration of quarantine were collected for analysis. For a total number of 992 valid questionnaires, clinical significance of anxiety symptoms was observed in 9.58% respondents according to clinical diagnostic standards in China. Statistical results showed population with different age, education level, health status and personnel category responded differently. Other characteristics such as gender, marital status, region, and acquaintance with suspected or confirmed cases of COVID-19 did not affect anxiety levels significantly. Respondents experienced different forms of quarantine showed different anxiety levels. Unexpectedly, longer durations of quarantine did not lead to significant increase of anxiety level. Our results suggest a rather mild psychological influence caused by the countrywide quarantine during COVID-19 outbreak in China and provided reference for other countries and regions to battle COVID-19.