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Nonstationary channel model of reentry plasma sheath for spacecraft: Overview, parameter estimation, and perspective

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Chinese Journal of Aeronautics 2024年第10期37卷 26-49页

作者： Lei SHI Zongyuan LIU Weimin BAO bo YAO Yifan WANG Xiaoping LI Yanming LIU Fangyan LI School of Aerospace Science and Technology Xidian UniversityXi’an 710126China Key Laboratory of Equipment Efficiency in Extreme Environment Ministry of EducationXi’an 710126China China Aerospace Science and Technology Corporation Beijing 100048China

The Tracking,Telemetering,and Command(TT&C)communication of spacecraft faces severe limitations during *** Electromagnetic(EM)propagation channel is influenced by changes in the flight state and fluid *** addition to the high-speed spatial channel,the Plasma Sheath Channel(PSC),which covers the surface of spacecraft,exhibits unique nonstationary and highly dynamic time-varying *** absence of a channel model for the reentry process of spacecraft negatively impacts the quality evaluation and system design of TT&C *** paper summarizes the methods for nonstationary PSC modeling,involving calculation methods for attenuation and phase shift in the channel,as well as a multistate nonstationary channel statistical model based on a hidden Markov ***,the correlation between amplitude variation and phase variation with electron density is *** paper also provides statistical characteristics of the channel and channel parameters at typical frequencies in the S/C/X/ka *** findings serve as a reference for the design and evaluation of TT&C communication systems for reentry ***,the paper discusses the prospects of various aspects related to the channel characteristics and modeling of spacecraft PSCs in the shortwave and terahertz/laser bands,as well as the potential challenges in cross-domain spacecraft channel sensing and prediction.

关键词： Spacecraft Plasma sheaths Electromagnetic wave transmission Communication channels Channel estimation

SARS-CoV-2 ORF10 hijacking ubiquitination machinery reveals potential unique drug targeting sites

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Acta Pharmaceutica Sinica B 2024年第9期14卷 4164-4173页

作者： kaixiang Zhu Lili Song Linyue Wang Lei Hua Ziyu Luo Tongyun Wang bo Qin Shuofeng Yuan Xiaopan Gao Wenyi Mi Sheng Cui NHC Key Laboratory of Systems Biology of Pathogens National Institute of Pathogen BiologyChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China Key Laboratory of Pathogen Infection Prevention and Control(Peking Union Medical College) Ministry of EducationBeijing 100730China The Province and Ministry Co-Sponsored Collaborative Innovation Center for Medical Epigenetics Key Laboratory of Immune Microenvironment and Disease(Ministry of Education)Tianjin Medical University General HospitalDepartment of ImmunologyTianjin Medical UniversityTianjin 300070China Medical School Yan’an UniversityShaanxi ProvinceYan’an 716000China State Key Laboratory of Emerging Infectious Diseases Li Ka Shing Faculty of Medicinethe University of Hong KongPokfulamHong Kong SARChina Department of Microbiology Li Ka ShingFaculty of Medicinethe University of Hong KongPokfulamHong Kong SARChina

Viruses often manipulate ubiquitination pathways to facilitate their replication and ***2ZYG11B known as the substrate receptor of cullin-2 RING E3 ligase,is bound by SARS-CoV-2 ORF10 to increase its E3 ligase activity,leading to degradation of IFT46,a protein component of the intraflagellar transport(IFT)complex *** results in dysfunctional cilia,which explains certain symptoms that are specific to ***,the precise molecular mechanism of how ORF10 recognizes CUL2ZYG11B remains ***,we determined the crystal structure of CUL2ZYG11B complexed with the N-terminal extension(NTE)of SARS-CoV-2 ORF10(2.9 A°).The structure reveals that the ORF10 N-terminal heptapeptide(NTH)mimics the Gly/N-degron to bind *** studies identified key residues within ORF10 that are key players in its interaction with CUL2ZYG11B both in ITC assay and in vivo *** addition,we prove that enhancement of CUL2ZYG11B activity for IFT46 degradation by which ORF10-mediated correlates with the binding affinity between ORF10 and ***,we used a Global Protein Stability system to show that the NTH of ORF10 mimics the Gly/N-degron motif,thereby binding competitively to CUL2ZYG11B and inhibiting the degradation of target substrates bearing the Gly/N-degron ***,this study sheds light on how SARS-CoV-2 ORF10 exploits the ubiquitination machinery for proteasomal degradation,and offers valuable insights for optimizing PROTAC-based drug design based on NTH CUL2ZYG11B interaction,while pinpointing a promising target for the development of treatments for COVID-19.

关键词： SARS-CoV-2 ORF10 Crystal structure cullin-2 RING E3 ligase Drug design

Identification of novel small-molecule inhibitors of SARS-CoV-2 by chemical genetics

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Acta Pharmaceutica Sinica B 2024年第9期14卷 4028-4044页

作者： Chris Chun-Yiu Chan Qian Guo Jasper Fuk-Woo Chan kaiming Tang Jian-Piao Cai Kenn ka-Heng Chik Yixin Huang Mei Dai bo Qin Chon Phin Ong Allen Wing-Ho Chu Wan-Mui Chan Jonathan Daniel Ip Lei Wen Jessica Oi-Ling Tsang Tong-Yun Wang Yubin Xie Zhenzhi Qin Jianli Cao Zi-Wei Ye Hin Chu Kelvin kai-Wang To Xing-Yi Ge Tao Ni Dong-Yan Jin Sheng Cui Kwok-Yung Yuen Shuofeng Yuan State Key Laboratory of Emerging Infectious Diseases Carol Yu Centre for InfectionDepartment of MicrobiologySchool of Clinical MedicineLi Ka Shing Faculty of Medicinethe University of Hong KongPokfulamHong Kong SAR 999077China Department of Infectious Diseases and Microbiology the University of Hong Kong-Shenzhen HospitalShenzhen 518000China Centre for Virology Vaccinology and TherapeuticsHong Kong Science and Technology ParkHong Kong SAR 999077China Academician Workstation of Hainan Province Hainan Medical University-the University of Hong Kong Joint Laboratory of Tropical Infectious DiseasesHaikou 571100China School of Biomedical Sciences Li Ka Shing Faculty of Medicinethe University of Hong KongPokfulamHong Kong SAR 999077China NHC Key Laboratory of Systems Biology of Pathogens Institute of Pathogen Biology Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China College of Biology Hunan Provincial Key Laboratory of Medical VirologyHunan UniversityChangsha 410082China

There are only eight approved small molecule antiviral drugs for treating *** them,four are nucleotide analogues(remdesivir,JT001,molnupiravir,and azvudine),while the other four are protease inhibitors(nirmatrelvir,ensitrelvir,leritrelvir,and simnotrelvir-ritonavir).Antiviral resistance,unfavourable drug‒drug interaction,and toxicity have been reported in previous *** there is a dearth of new treatment options for *** this work,a three-tier cell-based screening was employed to identify novel compounds with anti-SARS-CoV-2 *** compound,designated 172,demonstrated broad-spectrum antiviral activity against multiple human pathogenic coronaviruses and different SARS-CoV-2 variants of *** studies validated by reverse genetics showed that compound 172 inhibits the 3-chymotrypsin-like protease(3CLpro)by binding to an allosteric site and reduces 3CLpro dimerization.A drug synergistic checkerboard assay demonstrated that compound 172 can achieve drug synergy with nirmatrelvir in *** vivo studies confirmed the antiviral activity of compound 172 in both Golden Syrian Hamsters and K18 humanized ACE2 ***,this study identified an alternative druggable site on the SARS-CoV-23CLpro,proposed a potential combination therapy with nirmatrelvir to reduce the risk of antiviral resistance and shed light on the development of allosteric protease inhibitors for treating a range of coronavirus diseases.

关键词： SARS-CoV-2 High throughput screening Broad-spectrum antiviral treatment 3CLpro inhibitor Allosteric-site inhibitor Animal models Chemical genetics Reverse genetics

Unique anti-angiogenic effects,pharmacological targets and therapeutic mechanisms of Chinese herbal medicines for endometriosis

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Genes & Diseases 2024年第5期11卷 63-65页

作者： bo Liang Rui Dong Sze Wan Hung Yiran Li Yuezhen Lin Ling Wu Tao Zhang Gene Chi Wai Man Hui Xu Jacqueline Pui Wah Chung Chi Chiu Wang Guangdong Provincial Key Laboratory of Marine Biotechnology Institute of Marine SciencesShantou UniversityShantouGuangdong 515063China Department of Obstetrics and Gynaecology The Chinese University of Hong KongHong Kong SARChina Reproduction and Development Laboratory Li Ka Shing Institute of Health SciencesThe Chinese University of Hong KongHong Kong SARChina School of Biomedical Sciences The Chinese University of Hong KongHong Kong SARChina Chinese University of Hong Kong-Sichuan University Joint Laboratory in Reproductive Medicine The Chinese University of Hong KongHong Kong SARChina

Endometriosis is a common and benign angiogenesisdependent gynecological disorder,which refers to the proliferation and growth of endometrium-like tissues with neovasculature formation outside of the uterus.1 Available medical treatments for endometriosis containing hormonal and non-hormonal treatments had been limited for longterm usage by their side effects.2 Ideal medical treatment for endometriosis with efficacy to relieve symptoms and suppress endometriotic lesion growth and minimal side effects has been longing for decades.3 Angiogenesis is a promising therapeutic target for endometriosis.

关键词： therapeutic endometriosis herbal

A flexible ultra-broadband multi-layered absorber working at 2 GHz-40 GHz printed by resistive ink

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Chinese Physics B 2024年第2期33卷 329-333页

作者：汪涛闫玉伦陈巩华李迎胡俊毛剑波 School of Microelectronics Hefei University of TechnologyHefei 230601China Special Display and Imaging Technology Innovation Center of Anhui Province Academy of Photoelectric TechnologyHefei University of TechnologyHefei 230027China

A flexible extra broadband metamaterial absorber(MMA)stacked with five layers working at 2 GHz–40 GHz is *** layer is composed of polyvinyl chloride(PVC),polyimide(PI),and a frequency selective surface(FSS),which is printed on PI using conductive *** investigate this absorber,both one-dimensional analogous circuit analysis and three-dimensional full-wave simulation based on a physical model are *** crucial electromagnetic properties,such as absorption,effective impedance,complex permittivity and permeability,electric current distribution and magnetic field distribution at resonant peak points,are studied in *** shows that the working frequency of this absorber covers entire S,C,X,Ku,K and ka bands with a minimum thickness of 0.098λ_(max)(λ_(max) is the maximum wavelength in the absorption band),and the fractional bandwidth(FBW)reaches 181.1%.Moreover,the reflection coefficient is less than-10 dB at 1.998 GHz–40.056 GHz at normal incidence,and the absorptivity of the plane wave is greater than 80%when the incident angle is smaller than 50°.Furthermore,the proposed absorber is experimentally validated,and the experimental results show good agreement with the simulation results,which demonstrates the potential applicability of this absorber at 2 GHz–40 GHz.

关键词： extra broadband physical model flexible metamaterial absorber multi-layer frequency selective surface

Aortic heterogeneity across segments and under high fat/salt/glucose conditions at the single-cell level

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National Science Review 2020年第5期7卷 881-896页

作者： Dongxu He Aiqin Mao Chang-bo Zheng Hao kan ka Zhang Zhiming Zhang Lei Feng Xin Ma Wuxi School of Medicine and School of Food Science and Technology Jiangnan University School of Biotechnology Jiangnan University School of Pharmaceutical Science and Yunnan Key Laboratory of Pharmacology for Natural Products Kunming Medical University

The aorta, with ascending, arch, thoracic and abdominal segments, responds to the heartbeat, senses metabolites and distributes blood to all parts of the body. However, the heterogeneity across aortic segments and how metabolic pathologies change it are not known. Here, a total of 216 612 individual cells from the ascending aorta, aortic arch, and thoracic and abdominal segments of mouse aortas under normal conditions or with high blood glucose levels, high dietary salt, or high fat intake were profiled using single-cell RNA sequencing. We generated a compendium of 10 distinct cell types, mainly endothelial(EC), smooth muscle (SMC), stromal and immune cells. The distributions of the different cells and their intercommunication were influenced by the hemodynamic microenvironment across anatomical segments,and the spatial heterogeneity of ECs and SMCs may contribute to differential vascular dilation and constriction that were measured by wire myography. Importantly, the composition of aortic cells, their gene expression profiles and their regulatory intercellular networks broadly changed in response to high fat/salt/glucose conditions. Notably, the abdominal aorta showed the most dramatic changes in cellular composition, particularly involving ECs, fibroblasts and myeloid cells with cardiovascular risk factor-related regulons and gene expression networks. Our study elucidates the nature and range of aortic cell diversity,with implications for the treatment of metabolic pathologies.

关键词： aorta single-cell RNA sequencing cardiovascular disease

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多链接复杂网络指数同步的间歇事件触发控制

控制理论与应用 2024年第1期41卷 90-98页

作者：张宏礼齐文博郭英岭南师范学院数学与统计学院广东湛江524048 青岛理工大学理学院山东青岛266520

本文研究了基于间歇事件触发控制策略的延迟多链接复杂网络的指数同步问题,设计了一种间歇动态事件触发控制策略.相比于间歇静态事件触发控制策略,本文提出的控制策略是基于控制区间内的动态事件触发,极大地减少了事件触发次.并且,考虑... 详细信息

本文研究了基于间歇事件触发控制策略的延迟多链接复杂网络的指数同步问题,设计了一种间歇动态事件触发控制策略.相比于间歇静态事件触发控制策略,本文提出的控制策略是基于控制区间内的动态事件触发,极大地减少了事件触发次.并且,考虑的间歇控制的控制增益是自适应的,这具有动态调整的作用.基于图论和李雅普诺夫方法,本文给出了实现延迟多链接复杂网络指数同步的充分条件.此外,本文设计的控制策略能够排除Zeno现象.并且,将理论结果应用于一类振子系统的指数同步问题.最后,文章给出相应的数值仿真来验证理论结果的有效性和可行性.

关键词：复杂网络指数同步性间歇事件触发控制

Sheng Jiang San, traditional multi-herb formulation, exerts anti-influenza effects in vitro and in vivo via neuraminidaseinhibition and immune regulation

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中国药理学与毒理学杂志 2019年第9期33卷 738-739页

作者： ZHANG Tian-bo XIAO meng-jie Chun-Kwok WONG ka-Pun CHRIS MOK ZHAO Xin TI Hui-hui Pang-Chui SHAW State Key Laboratory of Respiratory Disease Guangdong Provincial Key Laboratory of Molecular Target&Clinical PharmacologySchool of Pharmaceutical Sciences and The Fifth Affiliated HospitalGuangzhou Medical UniversityGuangzhouChina The School of Life Sciences The Chinese University of Hong KongHong KongChina School of Public Health Li Ka Shing Faculty of MedicineThe University of Hong KongHong KongChina

OBJECTIVE Sheng Jiang San(SJS),a multi-herb formulation,is used in treating high fever,thirsty and anxiety in ancient China and it is sometimes used to treat seasonal influenza in ***,there is no evidencebased investigation and mechanism research to support SJS′s anti-influenza *** study aims to investigate the anti-influenza effect of SJS and its possible *** In this study,we examined the inhibitory effect of SJS against different influenza viruses on Madin-Darby canine kidney *** virus infected BALB/c mice were employed as in vivo model to evaluate the *** challenged with A/PR/8/34(H1N1)were orally administrated SJS 1 g·kg^-1 daily for seven days and monitored for 14 *** survival rate,body mass changes,lung index,lung viral load,histopathologic changes and immune-regulation of the mice were *** underlying anti-influenza virus mechanisms were studied by a series of biological assays in vitro to determine if hemagglutinin,ribonucleoprotein complex or nerauminidase were targets of *** SJS exerted a broad spectrum of inhibitory effects on multiple influenza strains in a dose-dependent *** IC50 of SJS against A/WSN/33(H1N1)was lower than 35 mg·L^-*** also protected 50%of mice from influenza virus PR8 *** lung index and the lung viral load of SJS treated mice were signifi⁃cantly decrease compared with untreated *** 2 g·L^-1 inhibited 80%of neuraminidase enzymatic *** also up-regulated TNF-αand IFN-αand down-regulated IL-2 of influenza virus induced *** SJS is a useful formulation for treating influenza virus infection.

关键词： Sheng Jiang San anti-influenza activity neuraminidase inhibition immuno-regulation

慢速-超慢速扩张中心岩浆匮乏区热液活动的渗透机理

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大地构造与成矿学 2024年第5期48卷 928-938页

作者：范庆凯程鹏冯博中国石化石油勘探开发研究院北京102206 北京大学石油与天然气研究中心北京100871 北华航天工业学院遥感信息工程学院河北廊坊065000

慢速-超慢速扩张洋中脊作为全球洋中脊系统重要的组成部分,其岩浆补给、岩石圈热力学状态在沿轴/离轴方向表现出显著的差异,并广泛发育岩浆匮乏甚至缺失区,如拆离断层、非转换不连续带和非岩浆段等,在这些区域也发育大量的热液活动。为... 详细信息

慢速-超慢速扩张洋中脊作为全球洋中脊系统重要的组成部分,其岩浆补给、岩石圈热力学状态在沿轴/离轴方向表现出显著的差异,并广泛发育岩浆匮乏甚至缺失区,如拆离断层、非转换不连续带和非岩浆段等,在这些区域也发育大量的热液活动。为探究慢速-超慢速扩张洋中脊岩浆匮乏区的热液驱动机制及可能的热源,本文通过数值模拟方法,结合岩石圈冷却-破裂理论模型来定量解释洋中脊热液系统的产生条件、对流强度和维持时间与其深部潜在热源的关系。调整岩石圈矿物尺寸至5 mm×5 mm时,岩石圈最大破裂深度为~5 km。数值模拟结果表明,在这种情况下,产生并维持热液系统的洋壳渗透率阈值为~1.6×10^(-16)m^(2),且渗透率越大,热液活动越强烈。在相同的设置下,低渗模型(k_(1)=1.7×10^(-16)m^(2))维持热液系统持续活动~170 ka。提高模型对流层渗透率(k_(2)=1.7×10^(-15)m^(2))不仅有效增强了热液系统的热量输出,也将热液活动时间延长至~470ka。结合数值模拟结果和地球物理发现,慢速-超慢速扩张洋中脊岩浆匮乏区的热液活动或受控于深部多期次岩浆侵入体的侵入-加热-冷却-破裂过程。在这一过程中,若在岩浆体和围岩温度降至无法维持热液活动之前发生新一期岩浆侵入,上覆热液系统得以维持,并表现出脉冲状的热量变化;反之,若新一期岩浆侵入滞后,热液活动将最终衰亡。岩浆侵入与热液对流之间的时间差可能是导致慢速-超慢速扩张洋中脊热液系统下伏热源无法确定的因素之一。

关键词：洋中脊热液活动岩浆匮乏区渗透机理驱动机制