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Spatiotemporal variation of rainy season span and precipitation recorded by lacustrine laminated pollen in the Tibetan Plateau during the past two millennia

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Science China Earth Sciences 2024年第3期67卷 789-801页

作者： Anning CUI houyuan LU Juzhi hou Xingqi LIU Deke XU Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Group of Alpine Paleoecology and Human Adaptation State Key Laboratory of Tibetan Plateau Earth SystemResources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Capital Normal University College of Resource Environment and Tourism Beijing 100048China

The quantitative reconstruction of the length of the rainy season and precipitation on the Tibetan Plateau(TP) is crucial for revealing the spatiotemporal evolution of the Westerlies and Asian summer monsoon, as well as its ecological and environmental effects. Accurately determining the start and end times of the rainy season on the Plateau remains challenging.This study determined the start and end times of the rainy season in different locations on the Plateau by identifying precipitation inflection points. We calculated the duration and precipitation amount of the rainy season and established a transfer function between the modern pollen assemblages and them. Then, we reconstructed the rainy season variations in Kusai Lake(northern TP) and Jiang Co(central TP) during the past two millennia. The results showed that, the rainy season precipitation in Kusai Lake recorded five periods of high precipitation: AD 580–680, 1000–1100, 1200–1450, 1550–1780, and 1920–present, corresponding to the stages with long rainy season. The rainy season precipitation sequence in Jiang Co recorded four periods of high precipitation: AD 80–500, 800–950, 1250–1450, and 1780–present, which is consistent with the long rainy season before AD 1000 but unclear afterward. Spatially, rainy season precipitation on the Plateau exhibited four patterns: “wet in both north and south” may be related to abnormally strong summer monsoons;“dry in both north and south” likely associated with weak Westerly wind and weak summer monsoon;“wet in the south and dry in the north” linked to strong summer monsoon and weak Westerly wind;and “dry in the south and wet in the north” connected to weak summer monsoon and strong Westerly wind. This study revealed the spatiotemporal evolution pattern of the rainy season onset and end, duration, and precipitation amount on the Plateau over the past two millennia. It provides natural background support for further understanding the coupling between Westerly wind and Asian summer monsoon.

关键词： Tibetan Plateau Past two millennia Rainy season length Rainy season precipitation Quantitative reconstruction

The corrosion characteristic and mechanism of Mg-5Y-1.5Nd-xZn-0.5Zr(x=0,2,4,6 wt.%)alloys in marine atmospheric environment

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Journal of Magnesium and Alloys 2024年第1期12卷 139-158页

作者： Quantong Jiang Dongzhu Lu Liren Cheng Nazhen Liu Baorong hou CAS Key Laboratory of Marine Environmental Corrosion and Bio-fouling Institute of OceanologyChinese Academy of SciencesNo.7 Nanhai RoadQingdao 266071PR China State Key laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesNo.5625 Renmin StreetChangchun 130022PR China Open Studio for Marine Corrosion and Protection Pilot National Laboratory for Marine Science and Technology(Qingdao)No.1 Wenhai RoadQingdao 266071PR China Sanya Institute of Oceanology South China Sea Institute of OceanologyChinese Academy of SciencesZhenzhou RoadSanya 572000PR China

The microstructure and precipitated phases of as-cast Mg-5Y-1.5Nd-x Zn-0.5Zr(x=0,2,4,6 wt.%)alloys were investigated by optical microscopy,scanning electron microscopy,energy-dispersive spectrometry and X-ray Diffraction.The exposure corrosion experiment of these magnesium alloys was tested in South China Sea and KEXUE vessel atmospheric environment.The corrosion characteristic and mechanism of magnesium alloys of Mg-5Y-1.5Nd-x Zn-0.5Zr(x=0,2,4,6 wt.%)alloys were analyzed by weight loss rate,corrosion depth,corrosion products and corrosion morphologies.The electrochemical corrosion tests were also measured in the natural seawater.The comprehensive results showed that Mg-5Y-1.5Nd-4Zn-0.5Zr magnesium alloy existed the best corrosion resistance whether in the marine atmospheric environment and natural seawater environment.That depended on the microstructure,type and distribution of precipitated phases in Mg-5Y-1.5Nd-4Zn-0.5Zr magnesium alloy.Sufficient quantity anodic precipitated phases in the microstructure of Mg-5Y-1.5Nd-4Zn-0.5Zr alloy played the key role in the corrosion resistance.

关键词： Marine atmospheric environment Exposure corrosion Magnesium alloy Corrosion rate Corrosion mechanism

Recent advances in the synthesis and application of N-heterocyclic carbene-based molecular cages

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Science China Chemistry 2024年第5期67卷 1510-1523页

作者： Qiongjie Chai Lixin Duan Yanzhe Ma Tianheng hou Tao Tu Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Department of ChemistryFudan UniversityShanghai 200438China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

N-Heterocyclic carbene(NHC)-based cages have emerged as a prominent and dynamic research area within the research field of chemistry. Leveraging the distinctive electronic and steric properties of NHC ligands, the design, synthesis, and application of these corresponding cages have garnered substantial scholarly interest. In recent years, we have witnessed the successful fabrication of diverse NHC-based cages through a range of synthetic methodologies, which hold significant potential for applications in molecular recognition and catalysis. In this review, we delve into the foundational synthetic strategies that underlie the creation of NHC-based cages, employing approaches encompassing metal–NHC chelation, coordination assembly,and covalent bonding. Additionally, we compile the diverse applications of these cages within catalytic processes and molecular recognition. Lastly, we shed light on the current limitations of synthesis and outline future trends in the development of NHCbased cages.

关键词： N-heterocyclic carbene molecular cages supramolecular chemistry synthetic strategies applications

Directly targeting BAX for drug discovery:Therapeutic opportunities and challenges

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2378-2401页

作者： Zhenwei Zhang Linghui hou Dan Liu Shenglin Luan Min Huang Linxiang Zhao Key Laboratory of Structure-Based Drugs Design&Discovery of Ministry of Education Shenyang Pharmaceutical UniversityShenyang 110016China China Resources Sanjiu Medical&Pharmaceutical Co. Ltd.Shenzhen 518000China

For over two decades,the development of B-cell lymphoma-2(Bcl-2)family therapeutics has primarily focused on anti-apoptotic proteins,resulting in the first-in-class drugs called BH3 mimetics,especially for Bcl-2 inhibitor Venetoclax.The pro-apoptotic protein Bcl-2-associated X protein(BAX)plays a crucial role as the executioner protein of the mitochondrial regulated cell death,contributing to organismal development,tissue homeostasis,and immunity.The dysregulation of BAX is closely associated with the onset and progression of diseases characterized by pathologic cell survival or death,such as cancer,neurodegeneration,and heart failure.In addition to conducting thorough investigations into the physiological modulation of BAX,research on the regulatory mechanisms of small molecules identified through biochemical screening approaches has prompted the identification of functional and potentially druggable binding sites on BAX,as well as diverse all-molecule BAX modulators.This review presents recent advancements in elucidating the physiological and pharmacological modulation of BAX and in identifying potentially druggable binding sites on BAX.Furthermore,it highlights the structural and mechanistic insights into small-molecule modulators targeting diverse binding surfaces or conformations of BAX,offering a promising avenue for developing next-generation apoptosis modulators to treat a wide range of diseases associated with dysregulated cell death by directly targeting BAX.

关键词： Apoptosis Pro-apoptotic protein BAX Dynamic conformational activation Small-molecule apoptosis modulators

An Advanced Image Processing Technique for Backscatter-Electron Data by Scanning Electron Microscopy for Microscale Rock Exploration

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Journal of Earth Science 2024年第1期35卷 301-305页

作者： Zhaoliang hou Kunfeng Qiu Tong Zhou Yiwei Cai Frontiers Science Center for Deep-time Digital Earth China University of GeosciencesBeijing 100083China Department of Geology University of ViennaVienna 1090Austria State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and ResourcesChinaUniversity of GeosciencesBeijing 100083China

Backscatter electron analysis from scanning electron microscopes(BSE-SEM)produces high-resolution image data of both rock samples and thin-sections,showing detailed structural and geochemical(mineralogical)information.This allows an in-depth exploration of the rock microstructures and the coupled chemical characteristics in the BSE-SEM image to be made using image processing techniques.Although image processing is a powerful tool for revealing the more subtle data“hidden”in a picture,it is not a commonly employed method in geoscientific microstructural analysis.Here,we briefly introduce the general principles of image processing,and further discuss its application in studying rock microstructures using BSE-SEM image data.

关键词： Image processing rock microstructures electron-based imaging data mining

Predictive factors for percutaneous nephrolithotomy bleeding risks

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Asian Journal of Urology 2024年第1期11卷 105-109页

作者： U Phun Loo Chun hou Yong Guan Chou Teh Urology Department Sarawak General HospitalKuchingMalaysia

Objective:This study aimed to identify predictive factors for percutaneous nephrolithotomy(PCNL)bleeding risks.With better risk stratification,bleeding in high-risk patient can be anticipated and facilitates early identification.Methods:A prospective observational study of PCNL performed at our institution was done.All adults with radio-opaque renal stones planned for PCNL were included except those with coagulopathy,planned for additional procedures.Factors including gender,co-morbidities,body mass index,stone burden,puncture site,tract dilatation size,operative position,surgeon's seniority,and operative duration were studied using stepwise multivariate regression analysis to identify the predictive factors associated with higher estimated hemoglobin(Hb)deficiency.Results:Overall,4.86%patients(n=7)received packed cells transfusion.The mean estimated Hb deficiency was 1.3(range 0-6.5)g/dL and the median was 1.0 g/dL.Stepwise multivariate regression analysis revealed that absence of hypertension(p=0.024),puncture site(p=0.027),and operative duration(p=0.023)were significantly associated with higher estimated Hb deficiency.However,the effect sizes are rather small with partial eta-squared of 0.037,0.066,and 0.038,respectively.Observed power obtained was 0.621,0.722,and 0.625,respectively.Other factors studied did not correlate with Hb difference.Conclusion:Hypertension,puncture site,and operative duration have significant impact on estimated Hb deficiency during PCNL.However,the effect size is rather small despite adequate study power obtained.Nonetheless,operative position(supine or prone),puncture number,or tract dilatation size did not correlate with Hb difference.The mainstay of reducing bleeding in PCNL is still meticulous operative technique.Our study findings also suggest that PCNL can be safely done by urology trainees under supervision in suitably selected patient,without increasing risk of bleeding.

关键词： Percutaneous nephrolithotomy Predictive factor Risk factor Bleeding Blood loss

A multi-functional MgF_(2)/polydopamine/hyaluronan-astaxanthin coating on the biodegradable ZE21B alloy with better corrosion resistance and biocompatibility for cardiovascular application

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Journal of Magnesium and Alloys 2024年第3期12卷 1102-1116页

作者： Yachen hou Xueqi Zhang Jingan Li Liguo Wang Shaokang Guan School of Materials Science and Engineering and Henan Key Laboratory of Advanced Magnesium Alloy and Key Laboratory of Materials Processing and Mold Technology(Ministry of Education) Zhengzhou UniversityZhengzhou 450001China

The cardiovascular diseases(CVD)continue to be the major threat to global public health over the years,while one of the effective methods to treat CVD is stent intervention.Biomedical magnesium(Mg)alloys have great potential applications in cardiovascular stents benefit from their excellent biodegradability and absorbability.However,excessive degradation rate and the delayed surface endothelialization still limit their further application.In this study,we modified a Mg-Zn-Y-Nd alloy(ZE21B)by preparing MgF_(2) as the corrosion resistance layer,the dopamine polymer film(PDA)as the bonding layer,and hyaluronic acid(HA)loaded astaxanthin(ASTA)as an important layer to directing the cardiovascular cells fate.The electrochemical test results showed that the MgF_(2)/PDA/HA-ASTA coating improved the corrosion resistance of ZE21B.The cytocompatibility experiments also demonstrated that this novel composite coating also selectively promoted endothelial cells proliferation,inhibited hyperproliferation of smooth muscle cells and adhesion of macrophages.Compared with the HAloaded rapamycin(RAPA)coating,our MgF_(2)/PDA/HA-ASTA coating showed better blood compatibility and cytocompatibility,indicating stronger multi-functions for the ZE21B alloy on cardiovascular application.

关键词： Biodegradable ZE21B alloy Reendothelialization Surface modification Hyaluronic acid Astaxanthin.

Impact of immunosenescence and inflammaging on the effects of immune checkpoint inhibitors

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Cancer Pathogenesis and Therapy 2024年第1期2卷 24-30页

作者： Chuandong hou Zining Wang Xuechun Lu Medical School of Chinese PLA Beijing 100853China Department of Hematology The Second Medical Center&National Clinical Research Center for Geriatric DiseasesChinese PLA General HospitalBeijing 100853China

Immune checkpoint inhibitors(ICIs)are employed in immunotherapeutic applications for patients with weakened immune systems and can improve the ability of T cells to kill cancer cells.Although ICIs can potentially treat different types of cancers in various groups of patients,their effectiveness may differ among older individuals.The reason ICIs are less effective in older adults is not yet clearly understood,but age-related changes in the immune system,such as immunosenescence and inflammation,may play a role.Therefore,this review focuses on recent advances in understanding the effects of immunosenescence and inflammation on the efficacy of ICIs.

关键词： Immunosenescence Inflammaging Immune checkpoint inhibitor

Systematic pan-cancer analysis reveals OGT and OGA as potential biomarkers for tumor microenvironment and therapeutic responses

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Genes & Diseases 2024年第4期11卷 1-4页

作者： Chunyan hou Ci Wu Wenge Zhu Huadong Pei Junfeng Ma Department of Oncology Lombardi Comprehensive Cancer CenterGeorgetown UniversityWashingtonDC 20007USA Department of Biochemistry and Molecular Medicine School of Medicine and Health ScienceGeorge Washington UniversityWashingtonDC20052USA

Protein O-linkedβ-N-acetylglucosamine(O-GlcNAc)modification(O-GlcNAcylation)is a unique monosaccharide modification of essential importance in physiology and pathology.1,2 As a highly dynamic process,O-GlcNAcylation is mediated by two paired enzymes:O-GlcNAc transferase(OGT)and O-GlcNAcase(OGA),which add or remove the modification from proteins,respectively.Emerging evidence demonstrates that the aberrant O-GlcNAcylation underlies the initiation,progression,and metastasis of cancer.

关键词： metastasis pathology therapeutic