Volatility connectedness among the Indian equity and major commodity markets under the COVID-19 scenario

In this paper, the dynamic relationship between the volatilities of both the Indian equity market and six major commodity markets is analyzed during the COVID-19 pandemic. We employ the time-varying parameters vector autoregression model (TVP-VAR) and wavelet coherence approach to assess the market connectedness. The results reveal a significant increase in volatility correlation and spillovers between the Indian equity market and the six major commodity markets after the outbreak of COVID-19. Furthermore, it was found that after the COVID-19 outbreak, the volatility from the commodity markets rapidly spilled over to the Indian equity market. The wavelet coherence also suggests that the Indian equity market and the six major commodity markets may exhibit higher levels of contagion over the medium and long term. This evidence has important implications for financial risk management, macroprudential policy design, and investors who are interested in the volatility linkages between the Indian markets and major commodities.

Volatility Spillovers Among the Three Places Across the Taiwan Strait: Evidence from a BEKK‐CARR Approach

This study introduces a new BEKK‐CARR model to explore the volatility spillover effects among mainland China, Hong Kong, and Taiwan stock markets during the COVID‐19 pandemic. We also extend the approach of Diebold and Yilmaz (2009, 2012) to infer a brand‐new volatility spillover index to discuss the bi‐directional volatility transmission. Our results show that the trading information flow among these three markets has changed significantly as a result of the COVID‐19 pandemic. The strength of volatility spillover is increasing during this momentous period. The Hong Kong stock market plays a pivotal role in volatility transmission. The values for half‐lives by exogenous shocks keep relatively low during the pandemic period. A reasonable explanation is that the trading information transmissions among stock markets are quicker than in the non‐pandemic period.

Epidemiological characteristics of COVID-19 caused by Delta SARS-CoV-2 variant in Xi'an in December 2021

OBJECTIVE: To understand the epidemiological characteristics of confirmed cases of COVID-19 in Xi 'an, Shaanxi Province during cluster outbreak and explore the prevention and control strategies for the epidemic caused by the Delta SARS-CoV-2 variant. METHODS: The confirmed cases of COVID-19 who were treated in Xi'an People's Hospital, a designated hospital, were enrolled in the study, the data of the patients such as baseline data, diagnostic types and initial symptoms were retrospectively reviewed. RESULTS: Among 703 confirmed cases of COVID-19, the gender ratio of male to female was 1.16:1, the age ranged between 10 months and 94 years old, with the median age 33 years old;the patients with mild symptoms(58.46%) and the patients with common symptoms(39.12%) were dominant. 70.13% of the patients were vaccinated with 2 doses of COVID-19 vaccine, 13.51% have not been vaccinated. In terms of the initial symptoms of COVID-19, the patients with cough accounted for 42.96%, the patients with pharyngeal symptoms accounted for 29.87%, and the patients with fever accounted for 25.60%. Totally 129 patients did not have obvious symptoms during the initial stage. There was significant difference in the influence of age and vaccination on severity of disease(P<0.05). The patients aged no less than 60 years old were the high-risk population for the severe(57.14%) and critically severe(66.67%) symptoms;the morbidity rates of severe symptoms(50.00%) and critically severe symptoms(66.67%) were high among the patients without vaccination. CONCLUSION: The local cluster outbreak caused by Delta SARS-CoV-2 variant in Xi 'an, Shaanxi province are characterized by strong transmission power and fast transmission. It is necessary to focus on the prevention and control among the populations of infants and old people, enhance the epidemiological surgery, precisely trace and isolate close contacts, identify and take interventions to illness condition in early stage. In daily prevention and control, fever, as a typical symptom, should be monitored, and it is necessary to boost the comprehensiveness and sensitivity of symptom monitoring. Universal vaccination remains one of the effective measures for protection of vulnerable populations.

Dysregulation of glutamine/glutamate metabolism in COVID-19 patients: A metabolism study in African population and mini meta-analysis.

Coronavirus disease 2019 (COVID-19) remains a serious global threat. The metabolic analysis had been successfully applied in the efforts to uncover the pathological mechanisms and biomarkers of disease severity. Here we performed a quasi-targeted metabolomic analysis on 56 COVID-19 patients from Sierra Leone in western Africa, revealing the metabolomic profiles and the association with disease severity, which was confirmed by the targeted metabolomic analysis of 19 pairs of COVID-19 patients. A meta-analysis was performed on published metabolic data of COVID-19 to verify our findings. Of the 596 identified metabolites, 58 showed significant differences between severe and nonsevere groups. The pathway enrichment of these differential metabolites revealed glutamine and glutamate metabolism as the most significant metabolic pathway (Impact = 0.5; -log10P = 1.959). Further targeted metabolic analysis revealed six metabolites with significant intergroup differences, with glutamine/glutamate ratio significantly associated with severe disease, negatively correlated with 10 clinical parameters and positively correlated with SPO2 (rs = 0.442, p = 0.005). Mini meta-analysis indicated elevated glutamate was related to increased risk of COVID-19 infection (pooled odd ratio [OR] = 2.02; 95% confidence interval [CI]: 1.17-3.50) and severe COVID-19 (pooled OR = 2.28; 95% CI: 1.14-4.56). In contrast, elevated glutamine related to decreased risk of infection and severe COVID-19, the pooled OR were 0.30 (95% CI: 0.20-0.44), and 0.44 (95% CI: 0.19-0.98), respectively. Glutamine and glutamate metabolism are associated with COVID-19 severity in multiple populations, which might confer potential therapeutic target of COVID-19, especially for severe patients.

Alterations in bile acids as metabolic signatures in the patients with human adenovirus type 7 infection.

Objectives: The changes in metabolism by human adenovirus (HAdV) infection was unclear. The potential mechanism of HAdV-7 causing acute respiratory tract infection was explored. Methods: Totally 35 patients with HAdV-7 infection, 32 asymptomatic cases with HAdV-7 and 14 healthy controls were enrolled from an outbreak of HAdV-7 in the army. The serum samples were analyzed by untargeted and targeted metabolomics. The effects of differential metabolites were verified on HAdV-7 replication in an A549 cell line. Results: The untargeted metabolomics analysis revealed more significant changes in the classes of sphingolipids, polyketides, glycerolipids, fatty acyls, and carboxylic acids and their derivatives in the patients with HAdV-7 than in healthy controls. Two key metabolic pathways of secondary and primary bile acid biosynthesis were noted from pathway enrichment analysis. Targeted metabolomics analysis showed that the levels of unconjugated bile acids in the patients were significantly lower, while the levels of glyco- and tauro- conjugated bile acids in patients and asymptomatic cases were higher than those in the healthy controls. The profiles of cytokines and peripheral lymphocyte subsets obviously varied at different levels of bile acids, with significant differences after HAdV-7 infection. A cell verification test demonstrated that the replication of HAdV-7 significantly reduced when GCDCA and TCA were added. Conclusion: Bile acids inhibited HAdV-7 replication in vitro. Alterations in bile acids was metabolic signatures of HAdV-7 infected subjects, and our results suggested bile acids might play protective roles against HAdV-7 infection.

Current Status of Phage Therapy against Infectious Diseases and Potential Application beyond Infectious Diseases.

Intestinal microbiota plays a key role in regulating the pathogenesis of human disease and maintaining health. Many diseases, mainly induced by bacteria, are on the rise due to the emergence of antibiotic-resistant strains. Intestinal microorganisms include organisms such as bacteria, viruses, and fungi. They play an important role in maintaining human health. Among these microorganisms, phages are the main members of intestinal viromes. In particular, the viral fraction, composed essentially of phages, affects homeostasis by exerting selective pressure on bacterial communities living in the intestinal tract. In recent years, with the widespread use and even abuse of antibacterial drugs, more and more drug-resistant bacteria have been found, and they show a trend of high drug resistance and multidrug resistance. Therefore, it has also become increasingly difficult to treat serious bacterial infections. Phages, a natural antibacterial agent with strong specificity and rapid proliferation, have come back to the field of vision of clinicians and scholars. In this study, the current state of research on intestinal phages was discussed, with an exploration of the impact of phage therapy against infectious diseases, as well as potential application beyond infectious diseases.

SARS-CoV-2 and Plasmodium falciparum Co-Infection in a Returning Traveler

Since December 2019, the Coronavirus Disease 2019 (COVID-19) pandemic has become a non-neglectable context for the whole healthcare system. Under the background of COVID-19, the detection and diagnosis of malaria cases are under challenge. Here, we reported a COVID-19 and malaria co-infection traveler who has a long living history in Cameroon. The case was administered with dihydroartemisinin and piperaquine tablets for malaria, Lopinavir and Ritonavir tablets, Arbidol, recombinant human interferon α-2b and Compound Maxing Yifei mixture for COVID-19, and Zolpidem Tartrate tablets, Diazepam, Paroxetine Hydrochloride tablets, Thymosin α1, and Lianhua Qinwen Jiaonang during the second hospitalization of the patient since the patient has a certain level of anxiety and insomnia with no evidence of inflammatory reactions. After being tested negative two times for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 48 h, the patient met China's COVID-19 discharge standards and was discharged with stable vital signs and mental state. Since most countries in the sub-Saharan region have a fragile health system, co-infection for both Plasmodium and SARS-CoV-2 may not be uncommon, and raise a challenge in diagnosis, treatment, and prevention for both diseases. We add to the literature on co-infection of P. falciparum malaria and COVID-19 and offer operational advice on diagnosis, prevention, and treatment for the co-infection.

Optimized Self-Adaptive Power Distribution for Microgrids in a Typical Tourism Water Village of Northern China under COVID-19 Background

This work presents an improved self-adaptive power distribution approach for the microgrid in five modes under different pandemic conditions in a typical tourism water village in Northern China. Differently from the other studies, this work concentrates on satisfying the specific power supply requirements under the COVID-19 background, with the maximum value of the composite index as the object function. Composite index includes not only the economic factors, but also some compulsive factors to ensure the requested power supply of the residents/tourists. The improved particle swarm optimization method which employs the modified weighted factor and the elite strategy is utilized to optimize the power dispatching of the microgrid. Moreover, the impact of the pandemic has been fully considered by comparing the power dispatching before and after the pandemic. The case study in Baiyangdian Region confirms the effectiveness of the proposed method. With this method, the optimal power dispatching is determined under different modes.

Modulating the Fluorescence of Silver Nanoclusters Wrapped in DNA Hairpin Loops via Confined Strand Displacement and Transient Concatenate Ligation for Amplifiable Biosensing.

It is intriguing to modulate the fluorescence emission of DNA-scaffolded silver nanoclusters (AgNCs) via confined strand displacement and transient concatenate ligation for amplifiable biosensing of a DNA segment related to SARS-CoV-2 (s2DNA). Herein, three stem-loop structural hairpins for signaling, recognizing, and assisting are designed to assemble a variant three-way DNA device (3WDD) with the aid of two linkers, in which orange-emitting AgNC (oAgNC) is stably clustered and populated in the closed loop of a hairpin reporter. The presence of s2DNA initiates the toehold-mediated strand displacement that is confined in this 3WDD for repeatable recycling amplification, outputting numerous hybrid DNA-duplex conformers that are implemented for a transient "head-tail-head" tandem ligation one by one. As a result, the oAgNC-hosted hairpin loops are quickly opened in loose coil motifs, bringing a significant fluorescence decay of multiple clusters dependent on s2DNA. Demonstrations and understanding of the tunable spectral performance of a hairpin loop-wrapped AgNC via switching 3WDD conformation would be highly beneficial to open a new avenue for applicable biosensing, bioanalysis, or clinical diagnostics.

Trends in secondary inorganic aerosol pollution in China and its responses to emission controls of precursors in wintertime

The Chinese government recently proposed ammonia (NH3) emission reductions (but without a specific national target) as a strategic option to mitigate fine particulate matter (PM2.5) pollution. We combined a meta-analysis of nationwide measurements and air quality modeling to identify efficiency gains by striking a balance between controlling NH3 and acid gas (SO2 and NOx) emissions. We found that PM2.5 concentrations decreased from 2000 to 2019, but annual mean PM2.5 concentrations still exceeded 35 µg m-3 at 74 % of 1498 monitoring sites during 2015–2019. The concentration of PM2.5 and its components were significantly higher (16 %–195 %) on hazy days than on non-hazy days. Compared with mean values of other components, this difference was more significant for the secondary inorganic ions SO42-, NO3-, and NH4+ (average increase 98 %). While sulfate concentrations significantly decreased over this period, no significant change was observed for nitrate and ammonium concentrations. Model simulations indicate that the effectiveness of a 50 % NH3 emission reduction for controlling secondary inorganic aerosol (SIA) concentrations decreased from 2010 to 2017 in four megacity clusters of eastern China, simulated for the month of January under fixed meteorological conditions (2010). Although the effectiveness further declined in 2020 for simulations including the natural experiment of substantial reductions in acid gas emissions during the COVID-19 pandemic, the resulting reductions in SIA concentrations were on average 20.8 % lower than those in 2017. In addition, the reduction in SIA concentrations in 2017 was greater for 50 % acid gas reductions than for the 50 % NH3 emission reductions. Our findings indicate that persistent secondary inorganic aerosol pollution in China is limited by emissions of acid gases, while an additional control of NH3 emissions would become more important as reductions of SO2 and NOx emissions progress.

Target Deoxyribonucleic Acid-Recycled Lighting-Up Amplifiable Ratiometric Fluorescence Biosensing of Bicolor Silver Nanoclusters Hosted in a Switchable Deoxyribonucleic Acid Construct.

Ratiometric assays of label-free dual-signaling reporters with enzyme-free amplification are intriguing yet challenging. Herein, yellow- and red-silver nanocluster (yH-AgNC and rH-AgNC) acting as bicolor ratiometric emitters are guided to site-specifically cluster in two template signaling hairpins (yH and rH), respectively, and originally, both of them are almost non-fluorescent. The predesigned complement tethered in yH is recognizable to a DNA trigger (TOC) related to SARS-CoV-2. With the help of an enhancer strand (G15E) tethering G-rich bases (G15) and a linker strand (LS), a switchable DNA construct is assembled via their complementary hybridizing with yH and rH, in which the harbored yH-AgNC close to G15 is lighted-up. Upon introducing TOC, its affinity ligating with yH is further implemented to unfold rH and induce the DNA construct switching into closed conformation, causing TOC-repeatable recycling amplification through competitive strand displacement. Consequently, the harbored rH-AgNC is also placed adjacent to G15 for turning on its red fluorescence, while the yH-AgNC is retainable. As demonstrated, the intensity ratio dependent on varying TOC is reliable with high sensitivity down to 0.27 pM. By lighting-up dual-cluster emitters using one G15 enhancer, it would be promising to exploit a simpler ratiometric biosensing format for bioassays or clinical theranostics.

A systematic review and meta-analysis of the mental health symptoms during the Covid-19 pandemic in Southeast Asia

Aims: The Covid-19 pandemic has had a substantial impact on the mental health of the general public and high-risk groups worldwide. Due to its proximity and close links to China, Southeast Asia was one of the first regions to be affected by the outbreak. The aim of this systematic review was to evaluate the prevalence of anxiety, depression and insomnia in the general adult population and healthcare workers (HCWs) in Southeast Asia during the course of the first year of the pandemic. Methods: Several literature databases were systemically searched for articles published up to February 2021 and two reviewers independently evaluated all relevant studies using pre-determined criteria. The prevalence rates of mental health symptoms were calculated using a random-effect meta-analysis model. Results: In total, 32 samples from 25 studies with 20 352 participants were included. Anxiety was assessed in all 25 studies and depression in 15 studies with pooled prevalence rates of 22% and 16%, respectively. Only two studies assessed insomnia, which was estimated at 19%. The prevalence of anxiety and depression was similar among frontline HCWs (18%), general HCWs (17%), and students (20%) while being noticeably higher in the general population (27%). Conclusions: This is the first systematic review to investigate the mental health impact of the Covid-19 pandemic in Southeast Asia. A considerable proportion of the general population and HCWs reported mild to moderate symptoms of anxiety and depression;the pooled prevalence rater, however, remain significantly lower than those reported in other areas such as China and Europe. (PsycInfo Database Record (c) 2022 APA, all rights reserved)

Meta-analytic evidence of depression and anxiety in Eastern Europe during the COVID-19 pandemic.

Objective: To perform a systematic and meta-analysis on the prevalence rates of mental health symptoms including anxiety and depression during the COVID-19 pandemic in the general population in Eastern Europe, as well as three select sub-populations: students, general healthcare workers, and frontline healthcare workers. Data sources: Studies in PubMed, Embase, Web of Science, PsycINFO, and medRxiv up to 6 February 2021. Eligibility criteria and data analysis: Prevalence rates of mental health symptoms in the general population and key sub-populations during the COVID-19 pandemic in Eastern Europe. Data were pooled using a random-effects meta-analysis to estimate the prevalence rates of anxiety and depression. Results: The meta-analysis identifies and includes 21 studies and 26 independent samples in Eastern Europe. Poland (n = 4), Serbia (n = 4), Russia (n = 3), and Croatia (n = 3) had the greatest number of studies. To our knowledge, no studies have been conducted in eleven Eastern European countries including Hungary, Slovakia, and Slovenia. The pooled prevalence of anxiety in 18 studies with 22 samples was 30% (95% CI: 24-37%) pooled prevalence of depression in 18 studies with 23 samples was 27% (95% CI: 21-34%). Implications: The cumulative evidence from the meta-analysis reveals high prevalence rates of clinically significant symptoms during the COVID-19 pandemic in Eastern Europe. The findings suggest evidence of a potential mental health crisis in Eastern Europe during the ongoing COVID-19 pandemic. Our synthesis also reveals a relative lack of studies in certain Eastern European countries as well as high heterogeneities among the existing studies, calling for more effort to achieve evidence-based mental healthcare in Eastern Europe.

Objetivo: Realizar un metanálisis sistemático sobre las tasas de prevalencia de síntomas de salud mental, incluidos ansiedad y depresión durante la pandemia de COVID-19 en la población general de Europa del Este, así como en tres subpoblaciones seleccionadas: estudiantes, trabajadores sanitarios generales y trabajadores sanitarios de primera línea.Fuentes de datos: Estudios en PubMed, Embase, Web of Science, PsycINFO y medRxiv hasta el 6 de febrero de 2021.Criterios de elegibilidad y análisis de datos: Tasas de prevalencia de síntomas de salud mental en la población general y subpoblaciones claves durante la pandemia de COVID-19 en Europa del Este. Los datos se combinaron mediante un metanálisis de efectos aleatorios para estimar las tasas de prevalencia de ansiedad y depresión.Resultados: El metanálisis identifica e incluye 21 estudios y 26 muestras independientes en Europa del Este. Polonia (n = 4), Serbia (n = 4), Rusia (n = 3) y Croacia (n = 3) tuvieron el mayor número de estudios. Hasta donde sabemos, no se han realizado estudios en once países de Europa del Este, incluidos Hungría, Eslovaquia y Eslovenia. La prevalencia combinada de ansiedad en 18 estudios con 22 muestras fue de 30% (IC del 95%: 24­37%) y la prevalencia combinada de depresión en 18 estudios con 23 muestras fue de 27% (IC del 95%: 21­34%).Implicaciones: La evidencia acumulada del metanálisis revela altas tasas de prevalencia de síntomas clínicamente significativos durante la pandemia de COVID-19 en Europa del Este. Los hallazgos sugieren evidencia de una posible crisis de salud mental en Europa del Este durante la pandemia de COVID-19 en curso. Nuestra síntesis también revela una relativa falta de estudios en ciertos países de Europa del Este, así como una gran heterogeneidad entre los estudios existentes, lo que exige un mayor esfuerzo para lograr una atención de la salud mental basada en la evidencia en Europa del Este.

Case Report: Respiratory Management With a 47-Day ECMO Support for a Critical Patient With COVID-19.

This paper reports a complete case of severe acute respiratory distress syndrome (ARDS) caused by coronavirus disease 2019 (COVID-19), who presented with rapid deterioration of oxygenation during hospitalization despite escalating high-flow nasal cannulation to invasive mechanical ventilation. After inefficacy with lung-protective ventilation, positive end-expiratory pressure (PEEP) titration, prone position, we administered extracorporeal membrane oxygenation (ECMO) as a salvage respiratory support with ultra-protective ventilation for 47 days and finally discharged the patient home with a good quality of life with a Barthel Index Score of 100 after 76 days of hospitalization. The purpose of this paper is to provide a clinical reference for the management of ECMO and respiratory strategy of critical patients with COVID-19-related ARDS.

A Systematic Review and Meta-Analysis of Symptoms of Anxiety, Depression, and Insomnia in Spain in the COVID-19 Crisis.

BACKGROUND: General population, frontline healthcare workers (HCWs), and adult students in Spain are at risk of anxiety, depression, and insomnia symptoms during the COVID-19 crisis. A meta-analysis of the individual studies on these symptoms would provide systematic evidence to aid policymakers and researchers in focusing on prevalence, risk, and best interventions. OBJECTIVE: This paper aims to be the first meta-analysis and systematic review to calculate the prevalence of anxiety, depression, and insomnia symptoms in Spain's adult population (general population, frontline healthcare workers (HCWs), and adult students) during the Covid-19 epidemic. METHOD: Random-effect meta-analysis was used to estimate the prevalence of anxiety, depression, and insomnia. RESULTS: The meta-analysis includes 28 studies with 38 individual samples in Spain. The pooled prevalence of anxiety symptoms in 22 studies comprising a sample population of 82,024 was 20% (95% CI: 15-25%), that of depression symptoms in 22 articles with a total sample comprising 82,890 individuals was 22% (95% CI: 18-28%), and that of insomnia symptoms in three articles with a sample population of 745 was 57% (95% CI: 48-66%. CONCLUSIONS: The accumulative evidence reveals that adults in Spain suffered higher prevalence rates of mental symptoms during the COVID-19 crisis, with a significantly higher rate relative to other countries such as China. Our synthesis also reveals a relative lack of studies on frontline and general HCWs in Spain.

2019 Novel Coronavirus-Infected Pneumonia on CT: A Feasibility Study of Few-Shot Learning for Computerized Diagnosis of Emergency Diseases.

COVID-19 is an emerging disease with transmissibility and severity. So far, there are no effective therapeutic drugs or vaccines for COVID-19. The most serious complication of COVID-19 is a type of pneumonia called 2019 novel coronavirus-infected pneumonia (NCIP) with about 4.3% mortality rate. Comparing to chest Digital Radiography (DR), it is recently reported that chest Computed Tomography (CT) is more useful to serve as the early screening and diagnosis tool for NCIP. In this study, aimed to help physicians make the diagnostic decision, we develop a machine learning (ML) approach for automated diagnosis of NCIP on chest CT. Different from most ML approaches which often require training on thousands or millions of samples, we design a few-shot learning approach, in which we combine few-shot learning with weakly supervised model training, for computerized NCIP diagnosis. A total of 824 patients are retrospectively collected from two Hospitals with IRB approval. We first use 9 patients with clinically confirmed NCIP and 20 patients without known lung diseases for training a location detector which is a multitask deep convolutional neural network (DCNN) designed to output a probability of NCIP and the segmentation of targeted lesion area. An experienced radiologist manually localizes the potential locations of NCIPs on chest CTs of 9 COVID-19 patients and interactively segments the area of the NCIP lesions as the reference standard. Then, the multitask DCNN is furtherly fine-tuned by a weakly supervised learning scheme with 291 case-level labeled samples without lesion labels. A test set of 293 patients is independently collected for evaluation. With our NCIP-Net, the test AUC is 0.91. Our system has potential to serve as the NCIP screening and diagnosis tools for the fight of COVID-19's endemic and pandemic.

Mental Health during the COVID-19 Crisis in Africa: A Systematic Review and Meta-Analysis.

We aim to provide a systematic review and meta-analysis of the prevalence rates of mental health symptoms among major African populations during the COVID-19 pandemic. We include articles from PubMed, Embase, Web of Science, PsycINFO, and medRxiv between 1 February 2020 and 6 February 2021, and pooled data using random-effects meta-analyses. We identify 28 studies and 32 independent samples from 12 African countries with a total of 15,071 participants. The pooled prevalence of anxiety was 37% in 27 studies, of depression was 45% in 24 studies, and of insomnia was 28% in 9 studies. The pooled prevalence rates of anxiety, depression, and insomnia in North Africa (44%, 55%, and 31%, respectively) are higher than those in Sub-Saharan Africa (31%, 30%, and 24%, respectively). We find (a) a scarcity of studies in several African countries with a high number of COVID-19 cases; (b) high heterogeneity among the studies; (c) the extent and pattern of prevalence of mental health symptoms in Africa is high and differs from elsewhere-more African adults suffer from depression rather than anxiety and insomnia during COVID 19 compared to adult populations in other countries/regions. Hence, our findings carry crucial implications and impact future research to enable evidence-based medicine in Africa.

Etiological and epidemiological features of acute respiratory infections in China.

Nationwide prospective surveillance of all-age patients with acute respiratory infections was conducted in China between 2009‒2019. Here we report the etiological and epidemiological features of the 231,107 eligible patients enrolled in this analysis. Children <5 years old and school-age children have the highest viral positivity rate (46.9%) and bacterial positivity rate (30.9%). Influenza virus, respiratory syncytial virus and human rhinovirus are the three leading viral pathogens with proportions of 28.5%, 16.8% and 16.7%, and Streptococcus pneumoniae, Mycoplasma pneumoniae and Klebsiella pneumoniae are the three leading bacterial pathogens (29.9%, 18.6% and 15.8%). Negative interactions between viruses and positive interactions between viral and bacterial pathogens are common. A Join-Point analysis reveals the age-specific positivity rate and how this varied for individual pathogens. These data indicate that differential priorities for diagnosis, prevention and control should be highlighted in terms of acute respiratory tract infection patients' demography, geographic locations and season of illness in China.

Discovery of potential small molecular SARS-CoV-2 entry blockers targeting the spike protein.

An epidemic of pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is spreading worldwide. SARS-CoV-2 relies on its spike protein to invade host cells by interacting with the human receptor protein Angiotensin-Converting Enzymes 2 (ACE2). Therefore, designing an antibody or small-molecular entry blockers is of great significance for virus prevention and treatment. This study identified five potential small molecular anti-virus blockers via targeting SARS-CoV-2 spike protein by combining in silico technologies with in vitro experimental methods. The five molecules were natural products that binding to the RBD domain of SARS-CoV-2 was qualitatively and quantitively validated by both native Mass Spectrometry (MS) and Surface Plasmon Resonance (SPR). Anti-viral activity assays showed that the optimal molecule, H69C2, had a strong binding affinity (dissociation constant KD) of 0.0947 µM and anti-virus IC50 of 85.75 µM.

Effects of Medical Masks on Voice Assessment During the COVID-19 Pandemic.

OBJECTIVE: Voice assessment is of great significance to the evaluation of voice quality. Our study aims to explore the effects of medical masks on healthy people in acoustic, aerodynamic and formant parameters during the COVID-19 pandemic. In addition, we also attempted to verify the differences between different sexes and ages. METHODS: Fifty-three healthy participants (25 males and 28 females) were involved in our study. The acoustic parameters, including fundamental frequency (F0), sound pressure level (SPL), percentage of jitter (%), percentage of shimmer (%), noise to harmonic ratio (NHR) and cepstral peak prominence (CPP), aerodynamic parameter (maximum phonation time, MPT) and formant parameters (formant frequency, F1, F2, F3) without and with wearing medical masks were included. We further investigated the potential differences in the impact on different sexes and ages (≤45 years old and >45 years old). RESULTS: While wearing medical masks, the SPL significantly increased (71.22±4.25 dB, 72.42±3.96 dB, P = 0.021). Jitter and shimmer significantly decreased (jitter 1.19±0.83, 0.87±0.67 P = 0.005; shimmer 4.49±2.20, 3.66±2.02 P = 0.002), as did F3 (2855±323.34 Hz, 2781.89±353.42 Hz P = 0.004). F0, MPT, F1 and F2 showed increasing trends without statistical significance, and NHR as well as CPP showed little change without and with wearing medical masks. There were no significant differences seen between males and females. Regarding to age, a significant difference in MPT was seen (>45-year-old 16.15±6.98 s, 15.38±7.02 s; ≤45-year-old 20.26±6.47 s, 21.44±6.98 s, P = 0.032). CONCLUSION: Healthy participants showed a significantly higher SPL, a smaller perturbation and an evident decrease in F3 after wearing medical masks. These changes may result from the adjustment of the vocal tract and the filtration function of medical masks, leading to the stability of voices we recorded being overstated. The impacts of medical masks on sex were not evident, while the MPT in the >45-year-old group was influenced more than that in the ≤45-year-old group.