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Reconstructing early transmission networks of SARS-CoV-2 using a genomic mutation model

Zoological Research 2023年第3期44卷 494-504页

作者： Chao-Yuan Cheng Zhi-Bin Zhang State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijing 100049China

The coronavirus disease 2019(COVID-19)pandemic has greatly damaged human society,but the origins and early transmission patterns of the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)pathogen remain unclear.Here,we reconstructed the transmission networks of SARS-CoV-2 during the first three and six months since its first report based on ancestor-offspring relationships using BANAL-52-referenced mutations.We explored the position(i.e.,root,middle,or tip)of early detected samples in the evolutionary tree of SARS-CoV-2.In total,6799 transmission chains and 1766 transmission networks were reconstructed,with chain lengths ranging from 1-9 nodes.The root node samples of the 1766 transmission networks were from 58 countries or regions and showed no common ancestor,indicating the occurrence of many independent or parallel transmissions of SARS-CoV-2 when first detected(i.e.,all samples were located at the tip position of the evolutionary tree).No root node sample was found in any sample(n=31,all from the Chinese mainland)collected in the first 15 days from 24 December 2019.Results using six-month data or RaTG13-referenced mutation data were similar.The reconstruction method was verified using a simulation approach.Our results suggest that SARS-CoV-2 may have already been spreading independently worldwide before the outbreak of COVID-19 in Wuhan,China.Thus,a comprehensive global survey of human and animal samples is essential to explore the origins of SARS-CoV-2 and its natural reservoirs and hosts.

关键词： SARS-CoV-2 Transmission chain Transmission network Ancestor-offspring relationship De novo mutation Back mutation Secondary mutation

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The effect of COVID-19 vaccines on sperm parameters: a systematic review and meta-analysis

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Asian Journal of Andrology 2023年第4期25卷 468-473页

作者： Yu-cheng Ma chao cheng Chi yuan Li-yuan Xiang Jun Wen Xi Jin Department of Urology Institute of Urology(Laboratory of Reconstructive Urology)West China HospitalSichuan UniversityChengdu 610000China

Published data were gathered for a meta-analysis to determine the difference in sperm parameters before and after administration of different types of coronavirus disease 2019(COVID-19)vaccines,because the reproductive toxicity of COVID-19 vaccines has not yet been evaluated in clinical trials and COVID-19 has been associated with decreases in sperm quality.The preferred procedures for systematic reviews and meta-analyses were followed in the conduct and reporting of this study.The average sperm parameters of all sperm donors’multiple sperm donations were compared before and after receiving various COVID-19 vaccinations.Semen volume,total sperm motility,total sperm count,morphological change,and sperm concentration were the primary outcome measures.We compiled and analyzed the results of six studies on total sperm motility,six studies on semen volume,six studies on sperm concentration,two studies on morphological change,and two studies on total sperm count.Parameter comparisons with patients who had and had not been vaccinated were only reported in one of the included studies.When different types of COVID-19 vaccine injections were compared,no discernible differences in parameters were observed.According to the available data,the parameters of semen are unaffected by inactivated or messenger RNA(mRNA)COVID-19 vaccinations.To support these findings,additional prospectively designed research is required.

关键词： COVID-19 mRNA vaccine sperm parameters sperm quality vaccine safety

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Theory-driven designed TiO_(2)@MoO_(2)heterojunction:Balanced crystallinity and nanostructure toward desirable kinetics and highrate sodium-ion storage

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Nano Research 2023年第4期16卷 4941-4949页

作者： Junyi Yin Pengqi Hai yuan Gao Zihan Gan chao Wu Yonghong cheng Xin Xu State Key Laboratory of Electrical Insulation and Power Equipment Center of Nanomaterials for Renewable EnergySchool of Electrical EngineeringXi’an Jiaotong UniversityXi’an 710049China Frontier Institute of Science and Technology Xi’an Jiaotong UniversityXi’an 710049China

Sodium-ion batteries(SIBs)are promising candidates for large-scale energy storage due to their cost effectiveness and the unlimited availability of sodium.However,there remains a need for the rational design of better anodic materials than are currently available,as these materials are critical for the sodium-ion storage process.In this work,theoretical calculations were performed to design a conceptually novel TiO_(2)@MoO_(2)heterojunction(TMH)anode that was expected to exhibit better electrochemical performance than current anodes.The TMH anode was fabricated via a facile and cost-effective method,and the results of in-depth sodium-ion-storage performance and reaction kinetics analyses indicate that it exhibited an excellent rate capability and enhanced pseudocapacitive response,due to its high crystallinity.This electrochemical performance was superior to that of previously reported anodic materials,confirming the accuracy of the theoretical calculations.Destruction of TMH’s nanostructure at high temperatures resulted in a decrease in its electrochemical performance,indicating the key role played by the nanostructure in TMH’s ability to store sodium ions.This study demonstrates that integration of theoretical predictions with experimental investigations offers insights into how materials’crystallinity and nanostructure affect their pseudocapacitive sodiumion storage capabilities,which will help to guide the rational design of effective anodic materials for SIBs.

关键词： theory-driven electrode development heterojunction crystallinity nanostructure enhanced pseudocapacitive response

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Boundary Control for a Class of Reaction-diffusion Systems

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International Journal of Automation and computing 2018年第1期15卷 94-102页

作者： yuan-chao Si cheng-Kang Xie Na Zhao School of Mathematics and System Science Southwest University School of Mathematics and System Science Guizhou University

Boundary control for a class of partial integro-differential systems with space and time dependent coefficients is consid- ered. A control law is derived via the partial differential equation （PDE） backstepping. The existence of kernel equations is proved. Exponential stability of the closed-loop system is achieved. Simulation results are presented through figures.

关键词： Stability reaction-diffusion system boundary control backstepping partial differential equation.

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Stability analysis of free surface of soil between piles in fabricated recyclable foundation pit supporting structure

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Yantu Lixue/Rock and Soil Mechanics 2020年 41卷 299-305页

作者： Chen, Li-chao Lin, Pei-yuan Guo, cheng-chao Wang, Fu-Ming School of Civil Engineering Sun Yat-sen University Guangzhou 510275 China Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) Zhuhai 519080 China Guangdong Provincial Key Laboratory of Oceanic Civil Engineering Sun Yat-sen University Guangzhou 510275 China Guangdong Provincial Research Center for Underground Space Exploitation Technology Guangzhou 510275 China

The stability of the free surface of the soil between the piles is of great significance for the engineering application of the assembled recyclable foundation pit support structure. In this paper, based on the calculation model of wedge-shaped body and the Terzaghi's theory on loosening earth pressure, considering the interaction between the soil and the pile-slab, the calculation formula of the ultimate supporting pressure of the free surface of the soil between the piles is derived from the limit equilibrium condition of the sliding mass. The calculated ultimate supporting pressure is compared with the numerical simulation results of three-dimensional finite element limit analysis to verify the rationality of the calculation method. The simple variable method was used to analyze the effects of soil internal friction angle φ, interface friction angle between soil and plates/piles δ, ground overload P0, spacing between piles B, relative excavation depth H/D, and unloading arch angle β on the ultimate support pressure. The research results can provide a theoretical basis for the soil support between the piles in the pile-slab support structure. © 2020, Science Press. All right reserved.

关键词： Piles

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Penetration and internal blast behavior of reactive liner enhanced shaped charge against concrete space

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Defence Technology（防务技术） 2022年第6期18卷 952-962页

作者： Hao Zhang yuan-feng Zheng Qing-bo Yu chao Ge cheng-hai Su Hai-fu Wang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China

Penetration and internal blast behavior of reactive liner enhanced shaped charge against concrete space were investigated through experiments and simulations.The volume of the enclosed concrete space is about 15 m^(3).The reactive liner enhanced shaped charge utilizes reactive copper double-layered liner,which is composed of an inner copper liner and an outer reactive liner,while the reactive material liner is fabricated by PTFE/Al(Polytetrafluoroethylene/Aluminum)powders through cold-pressing and sintering.Static explosion experiments show that,compared with the shaped charge which utilizes copper liner,the penetration cavity diameter and spalling area of concrete by the novel shaped charge were enlarged to 2 times and 4 times,respectively.Meanwhile,the following reactive material had blast effect and produced significant overpressure inside the concrete closed space.Theoretical analysis indicates concrete strength and detonation pressure of reactive material both affect the penetration cavity diameter.To the blast behavior of reactive material inside the concrete space,developing TNT equivalence model and simulated on AUTODYN-3 D for analysis.Simulation results reproduced propagation process of the shock wave in concrete space,and revealed multi-peaks phenomenon of overpressure-time curves.Furthermore,the empirical relationship between the peak overpressure and relative distance for the shock wave of reactive material was proposed.

关键词： Shaped charge Penetration Blast Concrete Numerical simulation

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Nitrogen Analogues of o-Quinodimethane with Unexpected non-Kekule Diradical Character

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Chinese Journal of Chemistry 2018年第6期36卷 487-490页

作者： Tao Li cheng cheng Ningning yuan Lei Wang chao Chen Gengwen Tan Xinping Wang State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical Engineering Collaborative Innovation Center of Advanced Microstructures Nanjing University Nanjing Jiangsu 210023 China

Two-electron oxidations of three 1,2-di（bisphenylamino）-benzenes afforded a class of nitrogen analogues of o-quinodimethane. Their elec-tronic structures in the ground state were studied by spectroscopic techniques including EPR and UV-vis absorption spectroscopy. They have open-shell singlet ground states with thermally accessible triplet states. One of them （12＋2） has been crystalized and isolated. SQUID measurements, single crystal X-ray diffraction and theoretical calculat ons show I has unexpected non-Kekule diradical character, sharply different from o-quinodirnethane.

关键词： o-quinodimethane diradicals triplet state X-ray structures DFT calculations

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Nanostructured bimetallic Zn/Co in N-doped carbon as an efficient catalyst for the alcohol dehydrogenation to carboxylic acids under solvent-free conditions

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Journal of Materials Science & Technology 2023年第30期161卷 111-122页

作者： Zhong-Hui Zheng Somboon Chaemchuen Jun-Fei Gu Jing Hang Wei Sang Ji-chao Wang Ye yuan cheng Chen State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

The catalytic alcohol dehydrogenation to carboxylic acids has been demonstrated as an atom-economic and environmental-friendly synthetic method.However,the reported catalysts either require relatively complicated synthesis or exhibit high activity only in the presence of a solvent.Therefore,it is still in high demand to obtain catalysts that feature facile synthesis and perform well even without any solvent.Herein,a series of nanostructured bimetallic Zn/Co species embedded in N-doped hierarchical porous carbon were fabricated in a facile and green manner.More significantly,the best-performing material(Zn/Co@NC-800)was identified as the first heterogeneous catalyst to enable this transformation under solvent-free conditions.Moreover,the as-prepared composites were comprehensively investigated to de-termine their structural and morphological properties,which rationalized the superiority of Zn/Co@NC-800 over the other synthesized materials.Further studies signified that Co sites(both Co^(0)and Co^(2+))and N species(mainly pyridinic N)were probably involved in this process,functioning as the Lewis acid site and basic site,respectively.Hopefully,this study could provide a simple and sustainable method for carboxylic acid synthesis.

关键词： Heterogeneous catalysis Bimetallic ZIFs Pyrolysis Solvent-free Alcohol dehydrogenation Carboxylic acids

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Tension pneumocephalus following endoscopic resection of a mediastinal thoracic spinal tumor:A case report

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World Journal of Clinical Cases 2022年第2期10卷 725-732页

作者： chao-yuan Chang cheng-Che Hung Ju-Mien Liu cheng-Di Chiu Department of Neurosurgery China Medical University HospitalTaichung 40447Taiwan Department of Pathology Puli Christian HospitalNantou 54041Taiwan

BACKGROUND Pneumocephalus is a rare complication presenting in the postoperative period of a thoracoscopic operation.We report a case in which tension pneumocephalus occurred after thoracoscopic resection as well as the subsequent approach of surgical management.CASE SUMMARY A 66-year-old man who received thoracoscopic resection to remove an intrathoracic,posterior mediastinal,dumbbell-shaped,pathology-proven neurogenic tumor.The patient then reported experiencing progressively severe headaches,especially when in an upright position.A brain computed tomography scan at a local hospital disclosed extensive pneumocephalus.Revision surgery for resection of the pseudomeningocele and repair of the cerebrospinal fluid leakage was thus arranged for the patient.During the operation,we traced the cerebrospinal fluid leakage and found that it might have derived from incomplete endoscopic clipping around the tumor stump near the dural sac at the T3 level.After that,we wrapped and sealed all the possible origins of the leakage with autologous fat,tissue glue,gelfoam,and duraseal layer by layer.The patient recovered well,and the computed tomography images showed resolution of the pneumocephalus.CONCLUSION This report and literature review indicated that the risk of developing a tension pneumocephalus cannot be ignored and should be monitored carefully after thoracoscopic tumor resection.

关键词： Tension pneumocephalus Neurogenic tumor Thoracoscope Case report

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Artificial intelligence computed tomography helps evaluate the severity of COVID-19 patients:A retrospective study

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World Journal of Emergency Medicine 2022年第2期13卷 91-97页

作者： Yi Han Su-cheng Mu Hai-dong Zhang Wei Wei Xing-yue Wu chao-yuan Jin Guo-rong Gu Bao-jun Xie chao-yang Tong Department of Emergency Medicine Zhongshan Hospital Fudan UniversityShanghai 200032China Department of Radiology Renmin Hospital of Wuhan UniversityWuhan 430060China

BACKGROUND:Computed tomography(CT)is a noninvasive imaging approach to assist the early diagnosis of pneumonia.However,coronavirus disease 2019(COVID-19)shares similar imaging features with other types of pneumonia,which makes differential diagnosis problematic.Artificial intelligence(AI)has been proven successful in the medical imaging field,which has helped disease identification.However,whether AI can be used to identify the severity of COVID-19 is still underdetermined.METHODS:Data were extracted from 140 patients with confirmed COVID-19.The severity of COVID-19 patients(severe vs.non-severe)was defined at admission,according to American Thoracic Society(ATS)guidelines for community-acquired pneumonia(CAP).The AI-CT rating system constructed by Hangzhou YITU Healthcare Technology Co.,Ltd.was used as the analysis tool to analyze chest CT images.RESULTS:A total of 117 diagnosed cases were enrolled,with 40 severe cases and 77 non-severe cases.Severe patients had more dyspnea symptoms on admission(12 vs.3),higher acute physiology and chronic health evaluation(APACHE)II(9 vs.4)and sequential organ failure assessment(SOFA)(3 vs.1)scores,as well as higher CT semiquantitative rating scores(4 vs.1)and AI-CT rating scores than non-severe patients(P<0.001).The AI-CT score was more predictive of the severity of COVID-19(AUC=0.929),and ground-glass opacity(GGO)was more predictive of further intubation and mechanical ventilation(AUC=0.836).Furthermore,the CT semiquantitative score was linearly associated with the AI-CT rating system(Adj R2=75.5%,P<0.001).CONCLUSIONS:AI technology could be used to evaluate disease severity in COVID-19 patients.Although it could not be considered an independent factor,there was no doubt that GGOs displayed more predictive value for further mechanical ventilation.

关键词： COVID-19 Artificial intelligence Chest computed tomography

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