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Carnot群上严格非正态极值的存在性

数学学报（中文版） 2014年第4期57卷 745-750页

作者：黄体仁南京理工大学应用数学系南京210094 中国科学技术大学数学科学学院合肥230022

设G是一个Carnot群,D={e1,e2}是G上一个左不变括号生成分布.在本文中,构造存在一类维数大于5的Carnot群,其上存在严格非正态极值.从而可知Gole,Karidi构造的第一个存在奇异测地线的Carnot群只是本文的一个特殊例子.

关键词：奇异测地线严格非正态极值 Carnot群

Total synthesis of(+)-taberdicatine B and(+)-tabernabovine B

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Chinese Chemical Letters 2025年第02期36卷 349-353页

作者： Tengfei Xuan Xinyu Zhang Wei Han Yidong huang Weiwu ren Molecular Synthesis Center&Key Laboratory of Marine Drugs Chinese Ministry of EducationSchool of Medicine and PharmacyOcean University of China Laboratory for Marine Drugs and Bioproducts Laoshan Laboratory

The first total synthesis of(+)-taberdicatine B and(+)-tabernabovine B has been accomplished in 10steps with 26.9% overall yield and 15 steps with 7.3% overall yield, respectively. The prominent features of this efficient synthetic strategy include the following:(1)(+)-Taberdicatine B and(+)-tabernabovine B were accessed from common advanced intermediates by varying the substituents;(2) A one-pot asymmetric bromocyclization/hydrolysis was explored to assemble HPI skeleton;(3) Dieckmann condensation to form β-keto ester for the assembly of seven-membered ring;(4) An ester reduction/amide semireduction/cyclization sequence was applied to form the cage-like framework.

关键词： Asymmetric dearomatization Hexahydropyrrolo[2,3-b]indole Taberdicatine B Tabernabovine B Total synthesis

Effect of lanthanum on microstructure of a nickel-based single crystal superalloy

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China Foundry 2025年第1期22卷 55-64页

作者： Hong Gao Kai Guan ren-jie Cui Jian-chao Qin Zi-han Zhao Zhao-hui huang Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical MaterialsBeijing 100095China

To enhance the high-temperature oxidation resistance and mechanical properties of a secondgeneration nickel-based superalloy,various concentrations of lanthanum(La)ranging from 5.0×10^(-5)wt.%to 3.4×10^(-4)wt.%are added to the *** microstructure of the nickel-based single crystal superalloy with trace of La was examined by means of SEM,EDS and *** show the addition of La decreases the segregation of elements and increases the amount ofγ/γ′eutectics of the as-cast alloy,and in the interdendritic region,the growth of eutectics is accompanied by the growth of strip clusters composed of Ni_(5)La and Ni_(3)*** the La content in the alloy increases,the proportion of Ni_(5)La in the cluster *** heat treatment,incipient melting occurs in the cluster regions,leading to an increase in microporosity compared to the original as-cast ***,the heat treatment alters the shape of the clusters from a strip morphology to an elliptical one,and it changes their composition from Ni_(5)La and Ni_(3)Ta to a combination of Ni_(5)La,Ni_(3)Ta,and MC carbides.

关键词： single crystal superalloy lanthanum microstructure heat-treatment precipitate phase

Success of intravenous immunoglobulin and steroids in managing severe COVID-19 following lung transplantation:A case report

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World Journal of Transplantation 2025年第1期15卷 178-184页

作者： Yen-Shou Kuo Kuan-Hsun Lin Ying-Yi Chen Yuan-Ming Tsai ti-Hui Wu Hsu-Kai huang Tsai-Wang huang Division of Thoracic Surgery Department of SurgeryTri-Service General HospitalNational Defense Medical CenterTaipei 114202Taiwan

BACKGROUND Coronavirus disease 2019(COVID-19)pneumonia with severe septic shock and acute respiratory distress syndrome(ARDS)are critical illnesses for patients following *** immunoglobulin(IVIG)plays a role in both immune support and inflammation control,especially in immunocompromised *** case report describes the first successful experience using IVIG and pulse steroids to manage this critical condition following lung *** SUMMARY A 65-year-old male patient reported a history of chronic obstructive pulmonary disease and poor lung function and received bilateral sequential lung ***,he developed COVID-19 pneumonia,severe septic shock,and *** recovered from this critical condition after empirical antibiotics administration and veno-venous extracorporeal membrane oxygenation,in addition to IVIG and pulse *** IVIG is a valuable adjunct in managing severe sepsis in lung transplant recipients after COVID-19 *** aim,for the first time,to report the success of such a management approach for COVID-19 ARDS and sepsis in the post-lung transplant *** further investigations,this is a starting point for wider analysis of such an approach in this setting and consequently helps guide clinical practice for such a challenging patient population moving forward.

关键词： COVID-19 Septic shock Intravenous immunoglobulin Lung transplantation Post-transplant complications Case report

Effect of two-pass rolling of textured roll and polished roll on surface topography and mechanical properties of 316L stainless steel ultra-thin strip

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Journal of Iron and Steel Research International 2025年第1期32卷 186-197页

作者： Zeng-qiang Zhang Xi Liao Zhong-kai ren Zhen-hua Wang Ya-xing Liu Tao Wang Qing-xue huang College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment of Ministry of Education Taiyuan University of TechnologyTaiyuan030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan030024ShanxiChina Shanxi tiSCO Stainless Steel Precision Strip Co. Ltd.Taiyuan030032ShanxiChina

The textured roll and polished roll were applied instead of the ground roll in a 20-high mill to conduct two-pass rolling of 316L stainless steel strip with thickness of 0.027 *** the two-pass rolling with the textured roll and polished roll(TPR),the surface roughness of the strip is dramatically reduced,and the surface topographical anisotropy index is diminished to 30.9%of the initial *** with the strip rolled using the ground roll in both passes(GGR),the elongation of TPR rolled strip is obviously improved,and the mechanical property anisotropy is greatly *** anisotropy index of tensile strength and elongation are 42.58%and 52.59%of that of GGR rolled strip,which is mainly attributed to the significant decrease of the texture intensity of the strip by TPR *** results indicate that TPR process can obtain the stainless steel ultra-thin strip with smooth and uniform surface topography and good mechanical properties.

关键词： Textured roll Polished roll Surface topography Mechanical property Stainless steel ultra-thin strip

Improving atmospheric pressure vertical correction model using Gaussian function

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Geodesy and Geodynamics 2025年第1期16卷 67-74页

作者： Baoshuang Zhang Junyu Li Lilong Liu Yibin Yao Liangke huang Chao ren Hongchang He Tengxu Zhang Yuxin Wang College of Geomatics and Geoinformation Guilin University of Technology Guangxi Key Laboratory of Spatial Information and Geomatics School of Geodesy and Geomatics Wuhan University School of Resources and Environmental Science and Engineering Hubei University of Science and Technology

The Zenith Hydrostatic Delay(ZHD) is essential for high-precision Global Navigation Satellite System(GNSS) and Very Long Baseline Interferometry(VLBI) data processing. Accurate estimation of ZHD relies on in situ atmospheric pressure, which is primarily variable in the vertical direction. Current atmospheric pressure is either site-specific or has limited spatial coverage, necessitating vertical corrections for broader applicability. This study introduces a model that uses a Gaussian function for the vertical correction of atmospheric pressure when in situ meteorological observations are unavailable. Validation with the fifth-generation European Centre for Medium-Range Weather Forecasts reanalysis(ERA5) reveals an average Bias and RMS for the new model of 0.31 h Pa and 2.96 h Pa,respectively. This corresponds to improvements of 37.5% and 80.3% in terms of RMS compared to two commonly used models(T0and Tvmodels) that require in situ meteorological observations,respectively. Additional validation with radiosonde data shows an average Bias and RMS of 1.85 h Pa and 4.87 h Pa, corresponding to the improvement of 42.8% and 71.1% in RMS compared with T0and Tv models, respectively. These accuracies are sufficient for calculating ZHD to an accuracy of 1 mm by performing atmospheric pressure vertical correction. The new model can correct atmospheric pressure from meteorological stations or numerical weather forecasts to different heights of the troposphere.

关键词： Atmospheric pressure Vertical correction Zenith hydrostatic delay (ZHD) Gauss function ERA5

Longitudinal landscape of immune reconstitution after acute SARS-CoV-2 infection at single-cell resolution

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Science Bulletin 2025年第3期70卷 323-327页

作者： Lili ren Yiwei Liu Yeming Wang Chao Wu Li Guo Lan Chen Xinming Wang Yan Xiao Lixue huang Jingchuan Zhong Jiacheng Yao Lu Liu Hui Li Ying Wang Yongchao Ma Yichunzi Zhang Lin Di Tao Dong Julian Knight Jianbin Wang Yanyi huang Bin Cao Xianwen ren Jianwei Wang National Health Commission Key Laboratory of Systems Biology of Pathogens and Christophe Mérieux Laboratory National Institute of Pathogen BiologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 102629China Key Laboratory of Respiratory Disease Pathogenomics Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100730China State Key Laboratory of Respiratory Health and Multimorbidity Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100029China Department of Pulmonary and Critical Care Medicine Institute of Respiratory Medicine of Chinese Academy of Medical ScienceNational Center for Respiratory MedicineCenter of Respiratory MedicineNational Clinical Research Center for Respiratory DiseasesChina-Japan Friendship HospitalBeijing 100029China College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China Biomedical Pioneering Innovation Center(BIOPIC) Beijing Advanced Innovation Center for Genomics(ICG)College of Chemistryand Peking-Tsinghua Center for Life SciencesPeking UniversityBeijing 100871China MRC Human Immunology Unit MRC Weatherall Institute of Molecular MedicineRadcliffe Department of MedicineThe University of OxfordOxford OX39DSUK Chinese Academy of Medical Science(CAMS)Oxford Institute(COI) University of OxfordOxford OX39DSUK Wellcome Centre for Human Genetics University of OxfordOxford OX39DSUK School of Life Sciences Tsinghua-Peking Center for Life SciencesTsinghua UniversityBeijing 100084China Beijing Advanced Innovation Center for Structural Biology(ICSB) Tsinghua UniversityBeijing 100084China Chinese Institute for Brain Research(CIBR) Beijing 102206China Institute for Cell Analysis Shenzhen Bay LaboratoryShenzhen 518107China Tsinghua University-Peking University Joint Center for Life Sciences Beijing 100084China Biomedical Pioneering Innovation Center(BIOPIC) Peking UniversityBeijing 100871China Changping Laboratory Beijing 102206China

The long-term consequences of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection,known as the post-acute sequelae of COVID-19(PASC),have been a growing concern.A significant proportion of COVID-19 patients experience persistent health issues even six to twelve months after recovering from acute infection[1],[2],[3],[4].Therefore,understanding the immune reconstitution process and identifying the molecular and cellular mechanisms underlying PASC is crucial.

关键词： landscape consequences acute

Statistical characteristics and classification of ionospheric mid-latitude trough as revealed by the observations of DMSP-F18

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Earth and Planetary Physics 2025年第1期9卷 137-147页

作者： Yi Liu JiuHou Lei FuQing huang Su Zhou School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China School of Science Guiyang UniversityGuiyang 550005China

Statistical characteristics and the classification of the topside ionospheric mid-latitude trough are systemically analyzed,using observations from the Defense Meteorological Satellite Program F18(DMSP-F18)*** data was obtained at an altitude of around 860 km in near polar orbit,throughout *** study identified the auroral boundary based on the in-situ electron density and electron spectrum,allowing us to precisely determine the location of the mid-latitude *** differs from most previous works,which only use Total Electron Content(TEC)or in-situ electron *** our study,the troughs exhibited a higher occurrence rate in local winter than in summer,and extended to lower latitudes with increasing geomagnetic *** was found that the ionospheric mid-latitude trough,which is associated with temperature changes or enhanced ion drift,exhibited distinct ***,the ionospheric mid-latitude troughs related to electron temperature(Te)peak were located more equatorward of auroral oval boundary in winter than in *** ionospheric mid-latitude troughs related to Te-maximum were less frequently observed at 60−70°S magnetic latitude and 90−240°E ***,the troughs related to ion temperature(ti)maximums were observed at relatively higher latitudes,occurring more frequently in *** addition,the troughs related to ion velocity(Vi)maximums could be observed in all *** troughs with the maximum-ti and maximum-Vi were located closer to the equatorward boundary of the auroral oval at the nightside,and in both *** implies that enhanced ion drift velocity contributes to increased collisional frictional heating and enhanced ion temperatures,resulting in a density depletion within the trough region.

关键词： topside ionosphere mid-latitude trough ionospheric main trough auroral oval boundary temperature maximum

The microbiome's influence on obesity: mechanisms and therapeutic potential

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Science China Life Sciences 2025年第3期 657-672页

作者： Dawit Adisu Tadese James Mwangi Lei Luo Hao Zhang Xiaoshan huang Brenda B.Michira Shengwen Zhou Peter Muiruri Kamau Qiumin Lu ren Lai Engineering Laboratory of Peptides of Chinese Academy of Sciences Key Laboratory of Bioactive Peptides of Yunnan Province KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common Diseases National Resource Center for Non-Human Primates National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility) Key Laboratory of Genetic Evolution & Animal Models Sino-African Joint Research Center and New Cornerstone Science Laboratory Kunming Institute of Zoology Chinese Academy of Sciences Kunming College of Life Sciences University of Chinese Academy of Sciences

In 2023, the World Obesity Atlas Federation concluded that more than 50% of the world's population would be overweight or obese within the next 12 years. At the heart of this epidemic lies the gut microbiota, a complex ecosystem that profoundly influences obesity-related metabolic health. Its multifaced role encompasses energy harvesting, inflammation, satiety signaling, gut barrier function, gut-brain communication, and adipose tissue homeostasis. Recognizing the complexities of the cross-talk between host physiology and gut microbiota is crucial for developing cutting-edge, microbiome-targeted therapies to address the global obesity crisis and its alarming health and economic repercussions. This narrative review analyzed the current state of knowledge, illuminating emerging research areas and their implications for leveraging gut microbial manipulations as therapeutic strategies to prevent and treat obesity and related disorders in humans. By elucidating the complex relationship between gut microflora and obesity, we aim to contribute to the growing body of knowledge underpinning this critical field, potentially paving the way for novel interventions to combat the worldwide obesity epidemic.

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