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Rock fracture mechanism of buffer blasting with cushion layer at the borehole bottom

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 325-334页

作者： Xinguang zhu Chenxi Ding Zhe sui Hong su Xu Guo School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 100083China School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China

This study primarily investigates the rock fracture mechanism of bottom cushion layer blasting and explores the effects of the bottom cushion layer on rock *** involves analyses of the evolution patterns of blasting stress,characteristics of crack distribution,and rock fracture features in the ***,blasting model experiments were carried out using the dynamic caustics principle to investigate the influence of bottom cushion layers and initiation methods on the integrity of the bottom rock *** experimental results indicate that the combined use of bottom cushion layers and inverse initiation effectively protects the integrity of the bottom rock ***,the process of stress wave propagation and dynamic crack propagation in rocks was simulated using the continuum-discontinuum element method(CDEM)and the Landau explosion source model,with varying thicknesses of bottom cushion *** numerical simulation results indicate that with increasing cushion thickness,the absorption of energy generated by the explosion becomes more pronounced,resulting in fewer cracks in the bottom rock *** illustrates the positive role of the cushion layer in protecting the integrity of the bottom rock mass.

关键词： bottom cushion layer blasting crack propagation continuum-discontinuum element method dynamic stress intensity factor

Reduced mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor contributes to neurodegeneration in a model of spinal and bulbar muscular atrophy pathology

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Neural Regeneration Research 2025年第9期20卷 2655-2666页

作者： Yiyang Qin Wenzhen zhu Tingting Guo Yiran Zhang Tingting Xing Peng Yin Shihua Li Xiao-Jiang Li su Yang Guangdong Key Laboratory of Non-human Primate Research Key Laboratory of CNS Regeneration(Ministry of Education)Guangdong–HongKong–Macao Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong ProvinceChina

Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto *** mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy *** aggregates alter protein-protein interactions and compromise transcriptional *** this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic *** n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor *** down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor *** findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy.

关键词： androgen receptor mesencephalic astrocyte-derived neurotrophic factor mouse model neurodegeneration neuronal loss neurotrophic factor polyglutamine disease protein misfolding spinal and bulbar muscular atrophy transcription factor

Effect of Ti Additions on Mechanical and Thermodynamic Properties of W-Ti Alloys: A First-principles Study

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 246-257页

作者： ZHANG Jian NIE Wei HUANG jin zhu Ke LIU Ruxia ZHANG Ruizhi LUO Guoqiang SHEN Qiang State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Institute for Carbon Neutrality University of Science and Technology BeijingBeijing 100083China

The mechanical and thermodynamic properties of W-Ti alloys(including W_(15)Ti_(1),W_(14)Ti_(2),W_(12)Ti_(4) and W_(8)Ti_(8) alloys)were investigated by the first-principles approach based on density functional *** results indicate that W-Ti alloys except W_(8)Ti_(8) are thermodynamically *** modulus and hardness of W-Ti alloys are smaller than those of pure tungsten and gradually decrease with increasing Ti ***,their B/G ratios and Poisson's ratios exceed those of pure tungsten,suggesting that the introduction of Ti decreases the mechanical strength while enhancing the ductility of W-Ti *** thermal expansion coefficients for W-Ti alloys all surpass those of pure tungsten,indicating that the introduction of titanium exacerbates the thermal expansion behavior of W-Ti ***,elevated pressure has the capacity to suppress the thermal expansion tendencies in titanium-doped tungsten *** study offers theoretical insights for the design of nuclear materials by exploring the mechanical and thermodynamic properties of W-Ti alloys.

关键词： first-principles mechanical properties thermodynamic properties tungsten-titanium alloys

Boosting aqueous nickel-zinc battery stability with bimetallic ion-integrated 1D metal-organic nanowires

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Science China Chemistry 2025年

作者： Yihao Chen jin Liang Yichun su Guoyin zhu Hengyue Xu Hongye Ding Guangxun Zhang Dianheng Yu Zizhou Shen Yizhou Zhang Wei Huang Huan Pang School of Chemistry and Chemical Engineering Yangzhou University Key Laboratory of Flexible Electronics (KLoFE) & Institute of Advanced Materials (IAM) School of Flexible Electronics (Future Technologies) Nanjing Tech University (NanjingTech) Institute of Advanced Materials and Flexible Electronics (IAMFE) School of Chemistry and Materials Science Nanjing University of Information Science & Technology Department of Chemistry Tsinghua University State Key Laboratory of Coordination Chemistry Nanjing University

Limited by low conductivity,designing cathode materials with excellent electron transfer efficiency for high-performance nickel-zinc batteries （NZBs） remains *** this study,a series of bimetallic metal-organic nanowires were fabricated by doping M ions in NiNTA,resulting in NiMNTA (M=Mg2+,Mn2+,Co2+,Zn2+,Ag+),and NixCo6-xNTA （x=1,2,3,4,5）.The proportions and types of metal ions can be modified without altering the initial coordination structure.X-ray absorption fine structure spectroscopy （XAFS） revealed that only M–O bonds,not metal bonds,were present in the *** performance of Ni2Co4NTA as the cathode for aqueous NZBs was significantly improved,achieving the maximum energy density of 279.17Wh kg-1with the high cycle stability （retention rate of 72.0%after 1,000 cycles）.The flexible Ni2Co4NTA//Zn@carbon cloth battery employing gel electrolyte also exhibits the excellent Coulombic efficiency of 96%after 350 *** approach shows considerable potential for designing one-dimensional materials with bimetallic modifications,providing new strategies for developing cathode materials for NZBs with high specific capacity and cycle stability.

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Research progress in metal-organic frameworks and their derivatives in electrochemistry

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Science China Chemistry 2025年

作者： Lingling Chen Yuxin Liu Yichun su Wenchen zhu Guangyu Du Huan Pang School of Chemistry and Chemical Engineering Yangzhou University Department of Applied Physics The Hong Kong Polytechnic University Interdisciplinary Materials Research Center Institute for Advanced Study Chengdu University State Key Laboratory of Coordination Chemistry Nanjing University

Metal-organic frameworks (MOFs) are distinguished by their unique porosity and meticulously ordered framework structures,setting them apart from conventional complexes. These materials are defined by their highly organized crystalline and pore structures, extensive surface areas, robust porosity, and superior adsorption capabilities. Owing to their exceptional structural and functional attributes, MOFs and their derivatives are leveraged across a broad spectrum of applications, demonstrating significant potential across diverse sectors. In recent times, the scientific community has increasingly focused on MOFs, underscoring their growing importance in research. Despite the promising array of applications for MOFs and their derivatives,challenges persist in practical deployments, and the pathway to research advancement remains daunting. This document delves into the synthesis and various applications of MOFs and their derivatives, particularly in the domains of energy storage, catalysis,sensing, and water treatment. It also highlights the ongoing research progress in the field of electrochemistry, including developments in lithium ion batteries (LIBs), lithium-sulfur batteries (LSBs), zinc-ion batteries (ZIBs), aqueous nickel-zinc batteries (NZBs), and supercapacitors. Finally, it provides an outlook on the future prospects and potential hurdles facing the development of MOF materials.

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Spatial transcriptomics combined with single-nucleus RNA sequencing reveals glial cell heterogeneity in the human spinal cord

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Neural Regeneration Research 2025年第11期20卷 3302-3316页

作者： Yali Chen Yiyong Wei jin Liu Tao zhu Cheng Zhou Donghang Zhang Department of Anesthesiology West China HospitalSichuan UniversityChengduSichuan ProvinceChina Laboratory of Anesthesia and Critical Care Medicine National-Local Joint Engineering Research Center of Translational Medicine of AnesthesiologyWest China HospitalSichuan UniversityChengduSichuan ProvinceChina Department of Anesthesiology Longgang District Maternity&Child Healthcare Hospital of Shenzhen City(Longgang Maternity and Child Institute of Shantou University Medical College)ShenzhenGuangdong ProvinceChina Department of Anesthesiology Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhou ProvinceChina

Glial cells play crucial roles in regulating physiological and pathological functions,including sensation,the response to infection and acute injury,and chronic neurodegenerative *** cells include astrocytes,microglia,and oligodendrocytes in the central nervous system,and satellite glial cells and Schwann cells in the peripheral nervous *** the greater understanding of glial cell types and functional heterogeneity achieved through single-cell and single-nucleus RNA sequencing in animal models,few studies have investigated the transcriptomic profiles of glial cells in the human spinal ***,we used high-throughput single-nucleus RNA sequencing and spatial transcriptomics to map the cellular and molecular heterogeneity of astrocytes,microglia,and oligodendrocytes in the human spinal *** explore the conservation and divergence across species,we compared these findings with those from *** the human spinal cord,astrocytes,microglia,and oligodendrocytes were each divided into six distinct transcriptomic *** the mouse spinal cord,astrocytes,microglia,and oligodendrocytes were divided into five,four,and five distinct transcriptomic subclusters,*** comparative results revealed substantial heterogeneity in all glial cell types between humans and ***,we detected sex differences in gene expression in human spinal cord glial ***,in all astrocyte subtypes,the levels of NEAT1 and CHI3L1 were higher in males than in females,whereas the levels of CST3 were lower in males than in *** all microglial subtypes,all differentially expressed genes were located on the sex *** addition to sex-specific gene differences,the levels of MT-ND4,MT2A,MT-ATP6,MT-CO3,MT-ND2,MT-ND3,and MT-CO_(2) in all spinal cord oligodendrocyte subtypes were higher in females than in ***,the present dataset extensively characterizes glial cell heterogeneity and offers a valuable resource for explo

关键词： astrocyte glial cell human microglia oligodendrocyte sex differentiation single-nucleus RNA sequencing spatial transcriptomics species variation spinal cord

RE-SEGNN:recurrent semantic evidence-aware graph neural network for temporal knowledge graph forecasting

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Science China(Information Sciences) 2025年

作者： Wenyu CAI Mengfan LI Xuanhua SHI Yuanxin FAN Quntao zhu Hai jin National Engineering Research Center for Big Data Technology and System Services Computing Technology and System Lab Cluster and Grid Computing Lab School of Computer Science and TechnologyHuazhong University of Science and Technology

Temporal knowledge graph(TKG) reasoning, has seen widespread use for modeling real-world events, particularly in extrapolation settings. Nevertheless, most previous studies are embedded models, which require both entity and relation embedding to make predictions, ignoring the semantic correlations among different entities and relations within the same timestamp. This can lead to random and nonsensical predictions when unseen entities or relations occur. Furthermore, many existing models exhibit limitations in handling highly correlated historical facts with extensive temporal depth. They often either overlook such facts or overly accentuate the relationships between recurring past occurrences and their current counterparts. Due to the dynamic nature of TKG, effectively capturing the evolving semantics between different timestamps can be *** address these shortcomings, we propose the recurrent semantic evidenceaware graph neural network(RE-SEGNN), a novel graph neural network that can learn the semantics of entities and relations simultaneously. For the former challenge, our model can predict a possible answer to missing quadruples based on semantics when facing unseen entities or relations. For the latter problem, based on an obvious established force, both the recency and frequency of semantic history tend to confer a higher reference value for the current. We use the Hawkes process to compute the semantic trend, which allows the semantics of recent facts to gain more attention than those of distant facts. Experimental results show that RE-SEGNN outperforms all SOTA models in entity prediction on 6 widely used datasets, and 5 datasets in relation prediction. Furthermore, the case study shows how our model can deal with unseen entities and relations.

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一类具有潜伏期的虫媒传染病模型的动力学分析

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生物数学学报 2016年第4期31卷 489-496页

作者：张晋珠苏铁熊中北大学机电工程学院山西太原030051 太原工业学院理学系山西太原030008

研究一类具有潜伏期的时滞虫媒传染病模型,确定了疾病是否流行的阈值.利用特征值理论分析了无病平衡点和地方病平衡点的稳定性,以时滞为参数,得到了系统在地方病平衡点产生Hopf分支的条件.数值模拟验证了理论研究的有效性.

关键词：虫媒传染病模型时滞稳定性 Hopf分支

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期 249-256页

作者： Qing-Yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian zhu Jie Han jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

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