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Anemoside B4 inhibits SARS-CoV-2 replication in vitro and in vivo

Chinese Herbal Medicines 2024年第1期16卷 106-112页

作者： Mingyue Xiao Ronghua Luo Qinghua Liang Honglv Jiang Yanli Liu guoqiang xu Hongwei Gao Yongtang Zheng Qiongming xu Shilin Yang College of Pharmaceutical Sciences Soochow UniversitySuzhou 215123China Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesKunming Institute of ZoologyChinese Academy of SciencesKunming 650223China Jiangsu Key Laboratory of Neuropsychiatric Diseases and Jiangsu Key Laboratory of Preventive and Translational Medicine for Geriatric Diseases Soochow UniversitySuzhou 215123China College of Pharmacy Guangxi University of Chinese MedicineNanning 530000China

Objective: Anemoside B4(AB4), the most abundant triterpenoidal saponin isolated from Pulsatilla chinensis, inhibited influenza virus FM1 or Klebsiella pneumoniae-induced pneumonia. However, the anti-SARS-CoV-2 effect of AB4 has not been unraveled. Therefore, this study aimed to determine the antiviral activity and potential mechanism of AB4 in inhibiting human coronavirus SARS-CoV-2 in vivo and in vitro.Methods: The cytotoxicity of AB4 was evaluated using the Cell Counting Kit-8(CCK8) assay. SARS-CoV-2 infected HEK293T, HPAEpiC, and Vero E6 cells were used for in vitro assays. The antiviral effect of AB4 in vivo was evaluated by SARS-CoV-2-infected hACE2-IRES-luc transgenic mouse model. Furthermore,label-free quantitative proteomics and bioinformatic analysis were performed to explore the potential antiviral mechanism of action of AB4. Type Ⅰ IFN signaling-associated proteins were assessed using Western blotting or immumohistochemical staining.Results: The data showed that AB4 reduced the propagation of SARS-CoV-2 along with the decreased Nucleocapsid protein(N), Spike protein(S), and 3C-like protease(3CLpro) in HEK293T cells. In vivo antiviral activity data revealed that AB4 inhibited viral replication and relieved pneumonia in a SARS-CoV-2 infected mouse model. We further disclosed that the antiviral activity of AB4 was associated with the enhanced interferon(IFN)-β response via the activation of retinoic acid-inducible gene Ⅰ(RIG-1) like receptor(RLP) pathways. Additionally, label-free quantitative proteomic analyses discovered that 17 proteins were significantly altered by AB4 in the SARS-CoV-2 coronavirus infections cells. These proteins mainly clustered in RNA metabolism.Conclusion: Our results indicated that AB4 inhibited SARS-CoV-2 replication through the RLR pathways and moderated the RNA metabolism, suggesting that it would be a potential lead compound for the development of anti-SARS-CoV-2 drugs.

关键词： anemoside B4 interferon RNA metabolism quantitative proteomics SARS-CoV-2

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Black-hole-inspired thermal trapping with graded heat-conduction metadevices

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National Science Review 2023年第2期10卷 131-138页

作者： Liujun xu Jinrong Liu Peng Jin guoqiang xu Jiaxin Li Xiaoping Ouyang Ying Li Cheng-Wei Qiu Jiping Huang Department of Physics State Key Laboratory of Surface Physics and Key Laboratory of Micro and Nano Photonic Structures (MOE) Fudan University Department of Electrical and Computer Engineering National University of Singapore Graduate School of China Academy of Engineering Physics School of Materials Science and Engineering Xiangtan University Interdisciplinary Center for Quantum Information State Key Laboratory of Modern Optical InstrumentationZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang University International Joint Innovation Center Key Laboratory of Advanced Micro/Nano Electronic Devices and Smart Systems of Zhejiang The Electromagnetics Academy of Zhejiang University Zhejiang University

The curved space-time produced by black holes leads to the intriguing trapping effect.So far,metadevices have enabled analogous black holes to trap light or sound in laboratory spacetime.However,trapping heat in a conductive environment is still challenging because diffusive behaviors are directionless.Inspired by black holes,we construct graded heat-conduction metadevices to achieve thermal trapping,resorting to the imitated advection produced by graded thermal conductivities rather than the trivial solution of using insulation materials to confine thermal diffusion.We experimentally demonstrate thermal trapping for guiding hot spots to diffuse towards the center.Graded heat-conduction metadevices have advantages in energy-efficient thermal regulation because the imitated advection has a similar temperature field effect to the realistic advection that is usually driven by external energy sources.These results also provide an insight into correlating transformation thermotics with other disciplines,such as cosmology,for emerging heat control schemes.

关键词： thermal trapping graded metadevices imitated advection

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Frictional resistance of supercritical pressure RP-3 flowing in a vertically downward tube at constant heat fluxes

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Chinese Journal of Aeronautics 2022年第9期35卷 117-128页

作者： Yinlong LIU guoqiang xu Yanchen FU Jie WEN Geng GONG Lulu LYU Research Institute of Aero-engine Beihang UniversityBeijing 100191China National Key Laboratory of Science and Technology on Aero-engine Aero-thermodynamics Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beihang Hangzhou Innovation Institute Yuhang Hangzhou 310023China China Aerodynamics Research and Development Center Mianyang 621000China AECC Commercial Aircraft Engine Co. Ltd.Shanghai 200241China

Based on the demands of compact heat exchangers and micro cooling channels applied for aviation thermal protection, the flow resistance characteristics of aviation kerosene RP-3 were experimentally studied in a vertically downward circular miniature tube with an inner diameter of 1.86 mm at supercritical pressures and constant heat fluxes. A long and short tube method was used to accurately calculate the frictional pressure drop, and experimental conditions are supercritical pressures of 4 MPa, mass flow rates of 2–4 g/s(i.e., mass fluxes of 736–1472 kg/(m^(2)·s)), heat fluxes of 100–500 kW/m^(2), and inlet temperatures of 373–673 K. Results show that the sharp variations of thermophysical properties, especially density, have significant influences on frictional resistances.Generally, the frictional pressure drop and the friction factor increase with increasing inlet temperatures, and this trend speeds up in the relatively high-temperature region. However, the friction factor has a sudden decline when the fuel outlet temperature exceeds the pseudo-critical temperature.The frictional pressure drop and the friction factor basically remain unchanged with increasing heat flux when the inlet temperature is relatively low, but increase quickly when the inlet temperature is relatively high. Besides, a larger mass flux yields a higher pressure drop but does not necessarily yield a higher friction factor. Finally, an empirical friction factor correlation is proposed and shows better predictive performance than those of previous models.

关键词： Aviation kerosene RP-3 Constant heat flux Empirical correlation Friction factor Supercritical pressure Vertical tube

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Airside pressure drop characteristics of three analogous serpentine tube heat exchangers considering heat transfer for aero-engine cooling

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Chinese Journal of Aeronautics 2022年第12期35卷 32-46页

作者： Yinlong LIU guoqiang xu Yanchen FU Jie WEN Shaoshuai QI Lulu LYU Research Institute of Aero-engine Beihang UniversityBeijing 100083China National Key Laboratory of Science and Technology on Aero-engine Aero-thermodynamics Beihang UniversityBeijing 100083China School of Energy and Power Engineering Beihang UniversityBeijing 100083China Beihang Hangzhou Innovation Institute Yuhang Hangzhou 310023China China Aerospace Aerodynamics Technology Research Institute Beijing 100074China AECC Commercial Aircraft Engine Co. Ltd.Shanghai 200241China

This study explores the design,analysis,and air pressure drop assessment of three analogous air–fuel heat exchangers consisting of thin serpentine tube bundles intended for use in high Mach number aero-engines.In high speed flight,the compressor bleed air used to cool high temperature turbine blades and other hot components is too hot.Hence,aviation kerosene is applied to precool the compressor bleed air by means of novel air–fuel heat exchangers.Three light and compact heat exchangers including dozens of in-line thin serpentine tube bundles were designed and manufactured,with little difference existing in aspects of tube pitches and outer diameters among three heat exchangers.The fuel flows inside a series of parallel stainless serpentine tubes(outer diameter:2.2,1.8,1.4 mm with 0.2 mm thickness),while the air externally flows normal to tube bundles and countercurrent with fuel.Experimental studies were carried out to investigate the airside pressure drop characteristics on isothermal states with the variation of air mass flow rates and inlet temperatures.Non-isothermal measurements have also been performed to research the effect of heat transfer on pressure drops.The experimental results show that inlet temperatures have significant influence on pressure drops,and higher temperatures lead to higher pressure drops at the same mass flow rate.The hydraulic resistance coefficient decreases quickly with Reynolds number,and the descent rate slows down when Re>6000 for all three heat exchangers.Additionally,the pressure drop on heat transfer states is less than that on isothermal states for the same average temperatures.Moreover,the pressure drop through heat exchangers is greatly affected by attack angles and transverse pitches,and an asymmetric M-shaped velocity profile is generated in the crosssection of sector channels.

关键词： Aero-engine Heat exchanger Heat transfer Pressure drop Serpentine tube

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Sequence and thermodynamic characteristics of terminators revealed by FlowSeq and the discrimination of terminators strength

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Synthetic and Systems Biotechnology 2022年第4期7卷 1046-1055页

作者： Weiji Zhai Yanting Duan Xiaomei Zhang guoqiang xu Hui Li Jinsong Shi Zhenghong xu Xiaojuan Zhang Biotechnology of Ministry of Education School of BiotechnologyJiangnan UniversityWuxiChina National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing Jiangnan UniversityWuxiChina School of Life Science and Health Engineering Jiangnan UniversityWuxi214122China Jiangsu Provincial Engineering Research Center for Bioactive Product Processing Jiangnan University1800 Lihu AvenueWuxi214122China

The intrinsic terminator in prokaryotic forms secondary RNA structure and terminates the transcription.However,leaking transcription is common due to varied terminator strength.Besides of the representative hairpin and U-tract structure,detailed sequence and thermodynamic features of terminators were not completely clear,and the effect of terminator on the upstream gene expression was unclearly.Thus,it is still challenging to use terminator to control expression with higher precision.Here,in E.Coli,we firstly determined the effect of the 3′-end sequences including spacer sequences and terminator sequences on the expression of upstream and downstream genes.Secondly,terminator mutation library was constructed,and the thermodynamic and sequence features differing in the termination efficiency were analyzed using the FlowSeq technique.The result showed that under the regulation of terminators,a negative correlation was presented between the expression of upstream and downstream genes(r=􀀀0.60),and the terminators with lower free energy corelated with higher upstream gene expression.Meanwhile,the terminator with longer stem length,more compact loop and perfect U-tract structure was benefit to the transcription termination.Finally,a terminator strength classification model was established,and the verification experiment based on 20 synthetic terminators indicated that the model can distinguish strong and weak terminators to certain extent.The results help to elucidate the role of terminators in gene expression,and the key factors identified are crucial for rational design of terminators,and the model provided a method for terminator strength prediction.

关键词： Intrinsic terminator Transcription termination Machine learning Structure-activity relationship FlowSeq Free energy

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Integral Real-time Locomotion Mode Recognition Based on GA-CNN for Lower Limb Exoskeleton

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Journal of Bionic Engineering 2022年第5期19卷 1359-1373页

作者： Jiaqi Wang Dongmei Wu Yongzhuo Gao Xinrui Wang Xiaoqi Li guoqiang xu Wei Dong State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China Weapon Equipment Research Institute China South Industries Group CorporationBeijing 102202China

The wearable lower limb exoskeleton is a typical human-in-loop human–robot coupled system,which conducts natural and close cooperation with the human by recognizing human locomotion timely.Requiring subject-specific training is the main challenge of the existing approaches,and most methods have the problem of insufficient recognition.This paper proposes an integral subject-adaptive real-time Locomotion Mode Recognition(LMR)method based on GA-CNN for a lower limb exoskeleton system.The LMR method is a combination of Convolutional Neural Networks(CNN)and Genetic Algorithm(GA)-based multi-sensor information selection.To improve network performance,the hyper-parameters are optimized by Bayesian optimization.An exoskeleton prototype system with multi-type sensors and novel sensing-shoes is used to verify the proposed method.Twelve locomotion modes,which composed an integral locomotion system for the daily application of the exoskeleton,can be recognized by the proposed method.According to a series of experiments,the recognizer shows strong comprehensive abilities including high accuracy,low delay,and sufficient adaption to different subjects.

关键词： Locomotion mode recognition Gait mode detection Lower limb exoskeleton Convolutional neural network Genetic algorithm Bionic design

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Effect of windage heating on a micro high-speed rotor-stator cavity

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Propulsion and Power Research 2022年第4期11卷 496-510页

作者： Jianyu Liu guoqiang xu Xi Zhao Bensi Dong Yongkai Quan National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics Research Institute of Aero-EngineBeihang UniversityBeijing100191China Beihang Hangzhou Innovation Institute Yuhang Xixi Octagon CityYuhang DistrictHangzhou310023China AECC Guiyang Engine Design Research Institute Guiyang550081China

The main objective of this work is to investigate the effect of windage heating on the micro high-speed rotor-stator cavity.The influences of centrifugal force and spacing on the windage heating are analyzed with and without the change of gap ratio respectively.The results demonstrate that there is no difference in the flow structure between micro and large-scale rotorstator cavities at the same rotational Reynolds number and gap ratio.However,the windage heating induced by the larger centrifugal force and smaller spacing brings the different heat transfer laws for the micro rotor-stator cavity.The larger centrifugal force weakens the local heat transfer near the rotor periphery.Such influence can be strengthened at higher rotational Reynolds numbers and lower rotor excess temperatures.Besides,the smaller spacing further enhances the windage heating and reduces the average heat transfer especially under the condition of lower gap ratio.The findings of this work contribute to the design of rotor-stator cavity utilized in the micro rotating machinery.

关键词： Micro rotor-stator cavity Flow Heat transfer Windage heating Centrifugal force Spacing

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Dynamics of triboelectric nanogenerators: A review

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International Journal of Mechanical System Dynamics 2022年第4期2卷 311-324页

作者： guoqiang xu Chuanyang Li Chaojie Chen Jingjing Fu Tingting Hou Yunlong Zi Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong Kong SARChina Shenzhen Research Institute The Chinese University of Hong KongGuangdongShenzhenChina HKUST Shenzhen‐Hong Kong Collaborative Innovation Research Institute GuangdongShenzhenChina Thrust of Sustainable Energy and Environment The Hong Kong University of Science and Technology(Guangzhou)GuangdongGuangzhouChina Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyHong Kong SARChina

Triboelectric nanogenerators(TENGs)represent a promising next‐generation renewable energy technology.TENGs have become increasingly popular for harvesting vibration energy in the environment due to their advantages of lightweight,broad range of material choices,low cost,and no pollution.However,issues such as input force irregularity,working bandwidth,efficiency calculation,and dynamic modeling hinder the use of TENGs in industrial or practical applications.In this paper,the modeling process of the dynamical system of a TENG is reviewed from the perspective of energy flow.In addition,this paper reviews the main contributions made in recent years to achieve optimized output based on springs,magnetic forces,and pendulums,and introduces different ways to increase the bandwidth of TENGs.Finally,the main problems of TENGs in the process of harvesting vibration energy are discussed.This review may serve as a practical reference for methods to convert irregular mechanical input sources into optimized output performance toward the commercialization of TENGs.

关键词： triboelectric nanogenerator vibration energy harvesting electromechanical coupling model broad bandwidth

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Characterization and implications of prokaryotic ribosome-binding sites across species

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Systems Microbiology and Biomanufacturing 2022年第4期2卷 676-684页

作者： Yanting Duan Xiaojuan Zhang Weiji Zhai Jinpeng Zhang Jiawei Ren Xiaomei Zhang guoqiang xu Jinsong Shi Zhenghong xu Biotechnology of Ministry of Education School of BiotechnologyJiangnan UniversityWuxiChina National Engineering Research Center for Cereal Fermentation and Food Biomanufacturing Jiangnan UniversityWuxiChina School of Life Science and Health Engineering Jiangnan UniversityWuxi 214122China Jiangsu Engineering Research Center for Bioactive Products Processing Technology Jiangnan University1800 Lihu AvenueWuxi 214122China

The ribosome-binding site(RBS)in the 5′untranslated region is recognized by 16S rRNA to start translation and is an essential element of the gene expression system.RBSs have been widely applied in regulating gene expression in various scenarios,including Gram-negative or Gram-positive bacteria.Here,we first rationally designed and constructed an RBS mutant library containing 66 RBSs.The strength of these RBSs in E.coli and C.glutamicum was characterized individually.The RBS strength spanned about 200 and 15 times in the two species,respectively.The strength of RBSs in C.glutamicum was generally lower than that of in E.coli.A total of 18 RBSs showed similar strength(within twofold differences)between the species in our study,and the correlation analysis of the strength of RBSs between E.coli and C.glutamicum(R^(2)=0.7483)revealed that these RBSs can be used across species.The sequence analysis revealed that the RBS region with two Ts stated was beneficial for RBS to function cross-species.The RBS characterized here can be used to precisely regulate gene expression in both hosts,and the characteristics of cross-species RBSs provide basic information for RBS rational design.

关键词： RBS library Cross-species RBSs Sequence characteristics Escherichia coli Corynebacterium glutamicum

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具有发酵工程学科特色的合成生物学研究生教学改革

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生物工程学报 2024年第6期40卷 1963-1971页

作者：徐国强余世琴周景文江南大学生物工程学院江苏无锡214122 江南大学粮食发酵与食品生物制造国家工程研究中心江苏无锡214122 江南大学未来食品科学中心江苏无锡214122

工业生物技术被认为是推动工业可持续发展最有希望的技术。合成生物学的发展为工业生物技术的进步带来了新的机遇同时创造了无限可能。发酵工程是所有生物技术产业化实现的抓手和落脚点。为进一步建立与发酵工程学科相匹配的合成生物学... 详细信息

工业生物技术被认为是推动工业可持续发展最有希望的技术。合成生物学的发展为工业生物技术的进步带来了新的机遇同时创造了无限可能。发酵工程是所有生物技术产业化实现的抓手和落脚点。为进一步建立与发酵工程学科相匹配的合成生物学教学体系,教学团队优化了教学内容,创新了教学模式,突出了教学特色(发酵故事讲述培养工匠精神、生物经济教育强化工程化思维和生物伦理与安全教育培育担当精神),并对本课程教学改革进行了总结和展望。通过教学改革,合成生物学的研究生教学工作有望取得新的进展,为相关领域的合成生物学教学提供参考,同时为工业生物技术的发展(加强生物制造创新能力,培育生物经济新动能)提供人才培养的保障。

关键词：工业生物技术合成生物学发酵工程教学改革

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