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Convergence of Hyperbolic Neural Networks Under Riemannian Stochastic Gradient Descent

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1175-1188页

作者： Wes Whiting bao Wang Jack {1. Department of Mathematics University of CaliforniaIrvineCAUSA Department of Mathematics Scientific Computing and Imaging InstituteUniversity of UtahSalt Lake CityUTUSA

We prove,under mild conditions,the convergence of a Riemannian gradient descent method for a hyperbolic neural network regression model,both in batch gradient descent and stochastic gradient *** also discuss a Riemann... 详细信息

关键词： Hyperbolic neural network Riemannian gradient descent Riemannian Adam(RAdam) Training convergence

Risk Factors of Depression Screened by Two-Sample Mendelian Randomization Analysis:A Systematic Review

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Biomedical and Environmental Sciences 2024年第1期37卷 85-95页

作者： WANG Han Lin XUE Yan Feng CUI bao Qiu LIU Hong SHEN {1. {1. Shandong Provincial Research Center for Bioinformatic Engineering and Technique School of Life SciencesShandong University of TechnologyZibo 255049ShandongChina Shanxi Province Cancer Hospital/Shanxi Hospital Affiliated to Cancer Hospital Chinese Academy of Medical Sciences/Cancer Hospital Affiliated to Shanxi Medical UniversityTaiyuan 030013ShanxiChina State Key Laboratory of Infectious Disease Prevention and Control National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China

Objective This study explored the potentially modifiable factors for depression and major depressive disorder(MDD)from the MR-Base database and further evaluated the associations between drug targets with *** We analyzed two-sample of Mendelian randomization(2SMR)using genetic variant depression(n=1.3,1.4)and MDD(n=208,81.)from Genome-Wide Association Studies(GWAS).Separate calculations were performed with modifiable risk factors from MR-Base for 1.001.*** MR analysis was performed by screening drug targets with MDD in the DrugBank database to explore the therapeutic targets for *** variance weighted(IVW),fixed-effect inverse variance weighted(FE-IVW),MR-Egger,weighted median,and weighted mode were used for complementary *** The potential causal relationship between modifiable risk factors and depression contained 459 results for depression and 424 for ***,the associations between drug targets and MDD showed that SLC6A4,GRIN2A,GRIN2C,SCN1.A,and IL1. expression are associated with an increased risk of *** contrast,ADRB1.CHRNA3,HTR3A,GSTP1.and GABRG2 genes are candidate protective factors against *** This study identified the risk factors causally associated with depression and MDD,and estimated 1. drug targets with significant impact on MDD,providing essential information for formulating strategies to prevent and treat depression.

关键词： Risk factors Drug targets Depression Major depressive disorder Two-sample Mendelian randomization

Large eddy simulation of boundary layer combustion of hydrogen and hydrocarbon fuel films in a modeled scramjet combustor

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Chinese Journal of Aeronautics 2024年第7期37卷 109-133页

作者： Jianfei WEI Silong ZHANG Jingying ZUO xin LI Jiang QIN Wen {1. School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China

Supersonic fuel film cooling is a promising way to simultaneously reduce the severe wall heat and friction load of the internal passage in a scramjet engine when operating at hypersonic *** eddy simulations were performed to investigate the cooling and wall friction characteristics of hydrogen and hydrocarbon films under inert and reactive *** results show that the essential difference of the turbulent state in the mixing layer contributes to the totally different behaviors of the cooling and wall friction reduction performances of the two fuel *** turbulent transport processes between the hydrogen film and the mainstream are much weaker as compared to the case of hydrocarbon film,making inert hydrogen rather superior in cooling and friction reduction ***,the increase of wall temperature for hydrogen film under the inert case is mainly driven by the loss of hydrogen with high heat capacity instead of by direct heat ***,the film cooling performance severely deteriorates when the hydrogen film burns due to presence of severe heat release sources near the *** the other hand,combustion of hydrocarbon film in the boundary layer can remarkably improve its originally barely-satisfactory cooling and friction reduction performance to the level comparable to that of hydrogen film,due to the suppression of turbulent transport processes in the mixing layer and presence of heat absorption sources near the ***,the hydrogen film is more advantageous in friction reduction,while the hydrocarbon film is more suitable for cooling.

关键词： Supersonic film cooling Hydrogen Hydrocarbon Boundary layer combustion Large eddy simulation

Activity regulation and applications of metal-organic framework-based nanozymes

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Rare Metals 2024年第3期43卷 900-914页

作者： Ge Fang Shou-xin {1. Gen-Xiu Zhou Cui-Cui Ge State Key Laboratory of Radiation Medicine and Protection School of Radiation Medicine and ProtectionSchool for Radiological and Interdisciplinary Sciences(RAD-X)Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou 215123China Suzhou Nanomicro Technology Co. LtdSuzhou 215000China

As a new generation of artificial enzymes,nanozymes show outstanding advantages such as high stability,low cost,and facile synthesis,which endow them with promising applications in biomedical and environmental *** the various reported nanozymes,metal-organic frameworks(MOFs)could mimic the active center of natural enzymes and provide a hydrophobic environment,which makes MOFs attractive alternatives to natural *** to the highly structural diversity and tailorability of MOFs,rational design will contribute to improve the activity of MOF-based nanozymes and promote their potential applications in both biomedical and environmental ***,a comprehensiye suminary of activity regulatory strategies of MOF-based nanozymes is urgently ***,we summarized the activity regulatory strategies of MOFs with intrinsic enzyme-like activities via modulation of metal nodes,ligands,structures and *** the applications of MOF-based nanozymes in biosensing,hazardous degradation,antibacterial,and cancer therapy were also ***,the current challenges and future perspectives were discussed in *** is highly expected that this review will provide a better understanding on the rational design of novel high-performance MOF-based nanozymes.

关键词： Metal-organic frameworks(MOF)-based nanozymes Activity regulation Biosensing Cancer therapy Hazardous degradation Antibacterial

Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea

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Petroleum Science 2024年第1期21卷 206-220页

作者： xin-Ru Wang {1.-Zhi Pan Yu-Hang Guo Qing-Hui Wang Yao Guan College of Geo-exploration Science and Technology Jilin UniversityChangchun130046JilinChina Research Institute CNOOC Ltd.-ShenzhenShenzhen518000GuangdongChina

There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir ***,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably *** the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous *** overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous ***,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric *** we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and ***,it is always difficult to determine the elemental eigenvalues of different minerals in *** paper uses multiple linear regression methods to solve this ***,an integrated inversion technique for altered igneous formations was *** results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray *** results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formation

关键词： Joint inversion Altered igneous rock Element correction method Lithology identification Multi mineral volume model

A new method for evaluating wedges of steel plates and strips

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Journal of Iron and Steel Research International 2024年第7期31卷 1719-1735页

作者： Xiao-bao Ma Xiao-{1. Ma Tao Wang Zhong-kai Ren Yu-cheng Ren College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Ministry of Education Engineering Research Center of Advanced Metal Composite Forming Technology and Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024ShanxiChina China National Heavy Machinery Research Institute Co. Ltd.Xi'an 710018ShaanxiChina Faculty of Mechanical Engineering Hebei University of ArchitectureZhangjiakou 075000HebeiChina

To overcome the inaccuracy problem of the traditional wedge evaluation of steel plates and strips caused by the ran-domness of the thicknesses of two local points and improve the reliability of the wedge index,the double-centroid method for the wedge evaluation was proposed,and a model based on the centroid theory was ***,an integral model for the discrete thickness values of the cross-section profiles was *** discussion focused on the distinct characteristics of the two-point method,asymmetric method,and double-centroid method in evaluating the asymmetric distribution of *** three methods were employed to evaluate the wedge values of both the theoretical and measured cross-sections of steel plates and strips,and the accuracies of three wedge evaluation models were analyzed and *** results showed that the double-centroid method objectively reflects the degree and variation characteristics of the wedge values of the cross-sections of steel plates and strips,and this method is feasible,reliable,and outstanding.

关键词： Steel plate and strip Wedge Two-point method Double-centroid method Reliability

Cutting performance of saw blades with microtextured rougher and finisher sawteeth

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Advances in Manufacturing 2024年第2期12卷 317-334页

作者： Yang Lu Jian-xin Deng Zhi-Hui Zhang Jia-xing Wu Ran Wang Yi-Chen bao Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE School of Mechanical EngineeringShandong UniversityJinan250061People’s Republic of China

The problems of severe sawtooth wear,harsh sawing noise,and low surface quality during the processing of circular saw blades need to be *** improve the cutting performance of TiC-based cermet saw blades,microtextures parallel to the cutting edge were fabricated on rough and fine sawteeth by laser *** cutting tests were performed on a sawing platform under lubricated *** of the sawing arc length and working sawtooth cutting force variations were developed for sawing steel pipes,and the accuracy of the sawing force model was verified *** results indicate that the variations in the sawing force are proportional to the sawing arc *** circular saw blades with microtextures that did not penetrate the sawtooth rake face exhibited the lowest cutting force,sawing noise,and highest machined surface ***,the worn-out distance of the rougher and finisher sawteeth was reduced by approximately 7.4%and 44.1.,respectively,compared with conventional circular saw *** main failure modes of sawteeth were tip wear,rake face adhesion,and oxidative *** addition,the mechanism by which the textures improve the cutting and wear properties of TiC-based circular saw blades was *** study provided a significant concept for enhancing the cutting performance of circular saw blades and improving the machined surface quality.

关键词： Circular saw blades Micro textures Cutting performance Wear performance

Stereoselective Self-Assembly of Chiral Metalla[2]Catenanes and Lemniscular Macrocycles

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CCS Chemistry 2024年第8期6卷 2000-2010页

作者： Shu-Jin bao Hai-Ning Zhang Guo-{1. Jin Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials State Key Laboratory of Molecular Engineering of PolymersDepartment of ChemistryFudan UniversityShanghai 200433

Designing and stereoselectively constructing chiral mechanically interlocked molecules(MIMs)is a goal that many chemists are pursuing due to their potential in the development of functional molecular machines involved in catalysis,sensing,and chiroptical ***,the synthesis of enantiopure supramolecular entities with crystallographic structures remains ***,the stereoselective self-assembly of chiral metalla[2]catenanes interlocked by two D-shaped macrocycles was realized by combining long binuclear half-sandwich organometallic Cp*Rh^(III)(Cp*=η^(5)-pentamethylcyclopentadienyl)clip and ditopic monodentate ligand incorporating L-leucine *** resulting metalla[2]catenane displayed unique co-conformational mechanical helical chirality characteristics arising from the chirality transfer of the chiral ***,decreasing the length of the binuclear Cp*Rh^(III)clip and adjusting the steric hindrance of the amino-acid side chains(L-alanine and L-phenylalanine)in the ligands resulted in two lemniscular macrocycles with left-handed(M)-twisted conformational *** the best of our knowledge,the synthesized macrocycles are the first family of homochiral abnormal lemniscate-shaped organometallic macrocycles featuring figure-eight ***[2]catenanes and macrocycles with opposite chirality were also generated by employing corresponding D-amino acid ligands,as evidenced by single-crystal X-ray diffraction,nuclear magnetic resonance,mass,and circular dichroism *** present study demonstrates that homochiral MIMs can be accessed readily using amino acid–containing ligands through rational molecular design.

关键词： stereoselective synthesis chirality metallacatenanes twisted macrocycles aminoacid residues

Impacts of Future Changes in Heavy Precipitation and Extreme Drought on the Economy over South China and Indochina

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Advances in Atmospheric Sciences 2024年第6期41卷 1184-1200,I0022-I0034页

作者： Bin TANG Wenting HU Anmin DUAN Yimin LIU Wen bao Yue {1. Xianyi YANG State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 101408China State Key Laboratory of Marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China Chinese Academy of Sciences the CAS Institutes of Science and DevelopmentBeijing 101408China School of Public Policy and Management University of Chinese Academy of SciencesBeijing 101408China

Heavy precipitation and extreme drought have caused severe economic losses over South China and Indochina(INCSC)in recent *** the areas with large gross domestic product(GDP)in the INCSC region are distributed along the coastline and greatly affected by global warming,understanding the possible economic impacts induced by future changes in the maximum consecutive 5-day precipitation(RX5day)and the maximum consecutive dry days(CDD)is critical for adaptation planning in this *** on the latest data released by phase 6 of the Coupled Model Intercomparison Project(CMIP6),future projections of precipitation extremes with bias correction and their impacts on GDP over the INCSC region under the fossil-fueled development Shared Socioeconomic Pathway(SSP5-8.5)are *** indicate that RX5day will intensify robustly throughout the INCSC region,while CDD will lengthen in most regions under global *** changes in climate consistently dominate the effect on GDP over the INCSC region,rather than the change of *** only considering the effect of climate change on GDP,the changes in precipitation extremes bring a larger impact on the economy in the future to the provinces of Hunan,Jiangxi,Fujian,Guangdong,and Hainan in South China,as well as the Malay Peninsula and southern Cambodia in ***,timely regional adaptation strategies are urgent for these ***,from the sub-regional average viewpoint,over two thirds of CMIP6 models agree that maintaining a lower global warming level will reduce the economic impacts from heavy precipitation over the INCSC region.

关键词： CMIP6 heavy precipitation extreme drought South China Indochina economic impact