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Integrating high-volume molecular and morphological data into the evolutionary studies of Allium

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Plant Diversity 2024年第1期46卷 1-2页

作者： xing-jin He Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610065SichuanPR China

The genus Allium(Amaryllidaceae),which includes economically important plants such as onions,garlic,and leeks,is one of the most species-rich and diverse genera of monocotyledon plants in the Northern Hemisphere(Govaerts et al.,2021),with approximately 1000 *** evolution of Allium is characterized by ecological diversification,with most species preferring open.

关键词： species evolutionary Allium

Configuration Synthesis and Grasping Performance Analysis of Multi-Loop Coupling Capture Mechanism for Launch and Recovery of Torpedo-Shaped Autonomous Underwater Vehicle

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china Ocean Engineering 2024年第3期38卷 453-466页

作者： ZHANG Guo-xing XIA Xin-lu GUO jin-wei School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling capture mechanism with strong adaptability and high retraction rate has been proposed for the launch and recovery of torpedo-shaped AUVs with different morphological ***,the principle of capturing motion retraction is described based on the appearance characteristics of torpedo-shaped AUVs,and the configuration synthesis of the capture mechanism is carried out using the method of constrained chain ***,the screw theory is employed to analyze the degree of freedom(DoF)of the capture ***,the 3D model of the capture mechanism is established,and the kinematics and dynamics simulations are carried *** with the capture orientation requirements of the capture mechanism,the statics and vibration characteristics analyses are carried ***,considering the capture process and the underwater working environment,the motion characteristics and hydraulics characteristics of the capture mechanism are ***,a principle prototype is developed and the torpedo-shaped AUVs capture experiment is *** work provides technical reserves for the research and development of AUV capture special equipment.

关键词： capture mechanism torpedo-shaped AUVs configuration synthesis launch and recovery grasping performance analysis

A hybrid memory architecture supporting fine-grained data migration

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Frontiers of Computer Science 2024年第2期18卷 31-41页

作者： Ye chi Jianhui YUE Xiaofei LIAO Haikun LIU Hai jin National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science and TechnologyHuazhong University of Science and TechnologyWuhan 430074China Department of Computer Science Michigan Technological UniversityMichigan 49931USA

Hybrid memory systems composed of dynamic random access memory(DRAM)and Non-volatile memory(NVM)often exploit page migration technologies to fully take the advantages of different memory *** previous proposals usually migrate data at a granularity of 4 KB pages,and thus waste memory bandwidth and DRAM *** this paper,we propose Mocha,a non-hierarchical architecture that organizes DRAM and NVM in a flat address space physically,but manages them in a cache/memory *** the commercial NVM device-Intel Optane DC Persistent Memory Modules(DCPMM)actually access the physical media at a granularity of 256 bytes(an Optane block),we manage the DRAM cache at the 256-byte size to adapt to this feature of *** design not only enables fine-grained data migration and management for the DRAM cache,but also avoids write amplification for Intel Optane *** also create an Indirect Address Cache(IAC)in Hybrid Memory Controller(HMC)and propose a reverse address mapping table in the DRAM to speed up address translation and cache ***,we exploit a utility-based caching mechanism to filter cold blocks in the NVM,and further improve the efficiency of the DRAM *** implement Mocha in an architectural *** results show that Mocha can improve application performance by 8.2%on average(up to 24.6%),reduce 6.9%energy consumption and 25.9%data migration traffic on average,compared with a typical hybrid memory architecture-HSCC.

关键词： non-volatile memory hybrid memory system data migration fine-grained caching

chiral boryl radical catalyzed asymmetric radical cycloisomerization

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Science china Chemistry 2024年第7期67卷 2121-2123页

作者： Jiamiao jin Shi-Chao Ren Yonggui Robin chi National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China School of Chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore

Asymmetric catalytic organic synthesis is of profound importance in modern research and industries,providing optically enriched molecules with diverse structures and functions[1].Enzymes,transition metal complexes,and simple organic molecules have all been found as powerful catalysts that enable the bond breaking and forming events with excellent control over stereo-selectivity *** the realm of designed small molecule organic catalysts.

关键词： radical catalyzed asymmetric

Embedded Majorana islands

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Science china(Physics,Mechanics & Astronomy) 2024年第9期67卷 154-164页

作者： jin-xing Hou Alex Weststrom Rui Wang Wen-Li Yang Jian Li Institute of Modern Physics Northwest UniversityXi’an 710127China Department of Physics School of ScienceWestlake UniversityHangzhou 310030China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi’an 710127China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310024China National Laboratory of Solid State Microstructures and Department of Physics Nanjing UniversityNanjing 210093China Collaborative Innovation Center for Advanced Microstructures Nanjing 210093China Peng Huanwu Center for Fundamental Theory Xi’an 710127China

Mesoscopic superconducting islands hosting Majorana zero modes(MZMs),or Majorana islands in short,offer a prototype of topological *** this work we investigate theoretically the model of a generic Majorana island tunneling-coupled to a singlepiece metallic substrate,hence an embedded Majorana *** show the crucial consequences of an interplay between the topological ground states nonlocally addressed by the MZMs and the metallic bath with coherent electron propagation:on the one hand,the topological degeneracy on the Majorana island can be preserved,by virtue of the particle-hole symmetry,despite the apparent bath-induced coupling between MZMs;on the other hand,the electronic interference in the metallic bath may lead to profound alterations to the renormalization group behavior of the hybrid system towards low energy/temperature compared with conventional Kondo *** work serves to establish the model of embedded Majorana islands as an experimentally relevant and theoretically intriguing problem particularly in the direction of topological quantum computation.

关键词： topological quantum computation Majorana zero modes topological qubit mesoscopic superconductor topological Kondo effect

A Review on Nanomaterial-based Strategies for Manipulating Tumor Microenvironment to Enhance Chemodynamic Therapy

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Chemical Research in chinese Universities 2024年第2期40卷 202-212页

作者： CAO Mengyu xing Xiner SHEN Xiaotong OUYANG jin NA Na Key Laboratory of Radiopharmaceuticals Ministry of EducationCollege of ChemistryBeijing Normal UniversityBeijing100875P.R.China Department of Chemistry College of Arts and SciencesBeijing Normal University at ZhuhaiZhuhai519087P.R.China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan430074P.R.China

Cancer is a leading cause of death worldwide,and a series of strategies has been reported for tumor-specific ***,chemodynamic therapy(CDT)has become a research hotspot for antitumor treatment due to its advantages of high specificity,endogenous stimulation,and high ***,the therapeutic effects of CDT are normally limited in the complex tumor microenvironment(TME),such as insufficient acidity,tumor hypoxia,low hydrogen peroxide(H2O2),and high glutathione(GSH).Consequently,different kinds of multifunctional nanomaterials have been designed to manipulate TME conditions,which provided more opportunities to improve the efficiency of *** review focuses on nanomaterial-based strategies for enhancing CDT through manipulating *** CDT enhancements,this review would provide a reference for the future development of efficient CDT nanomaterials.

关键词： Chemodynamic therapy Tumor microenvironment Nanomaterial Manipulating strategy Fenton/Fenton-like reaction

Tuning mechanical and electrical performances of B_(4)C-TiB_(2)ceramics in a two-step spark plasma sintering process

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Journal of Advanced Ceramics 2024年第4期13卷 518-528页

作者： Jun Zhao xingshuo Zhang Zongning Ma Dong Wang xing jin Songlin Ran Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMaanshan 243002China Anhui Engineering Research Center for High Efficiency Intelligent Photovoltaic Module Chaohu UniversityHefei 238024China

B_(4)C–TiB_(2)is an advanced electrically conductive ceramic with excellent mechanical and electrical discharge machinable *** is challenging and rewarding to achieve highly conductive and hard B_(4)C–TiB_(2)composites at a minimum content of conductive TiB2 that has inferior hardness but double specific gravity of the B_(4)C matrix.A novel strategy was used to construct conductive networks in B_(4)C‒15 vol%TiB2 composite ceramics with B_(4)C,TiC,and amorphous B as raw materials by a two-step spark plasma sintering *** influences of particle size matching between B_(4)C and TiC on the conducting of the strategy and the microstructure were discussed based on the selective matrix grain growth *** mechanical and electrical properties were also systematically *** B_(4)C–15 vol%TiB2 composite ceramic prepared from 10.29µm B_(4)C and 0.05µm TiC powders exhibited a perfect three-dimensional interconnected conductive network with a maximum electrical conductivity of 4.25×10^(4)S/m,together with excellent mechanical properties including flexural strength,Vickers hardness,and fracture toughness of 691±58 MPa,30.30±0.61 GPa,and 5.75±0.32 MPa·m^(1/2),respectively,while the composite obtained from 3.12µm B_(4)C and 0.8µm TiC powders had the best mechanical properties including flexural strength,Vickers hardness,and fracture toughness of 827±35 MPa,32.01±0.51 GPa,and 6.45±0.22 MPa·m^(1/2),together with a decent electrical conductivity of 0.65×10^(4)S/m.

关键词： B_(4)C-TiB_(2) mechanical properties electrical conductivity conductive network

Access to Axially chiral Aryl Aldehydes via Carbene-Catalyzed Nitrile Formation and Desymmetrization Reaction

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Research 2024年第3期2024卷 715-721页

作者： Yuanlin Cai Ya Lv Liangzhen Shu Zhichao jin Yonggui Robin chi Tingting Li National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China School of Chemistry Chemical Engineeringand BiotechnologyNanyang Technological UniversitySingapore 637371Singapore.

An approach utilizing N-heterocyclic carbene for nitrile formation and desymmetrization reaction is developed. The process involves kinetic resolution, with the axially chiral aryl monoaldehydes obtained in moderate yields with excellent optical purities. These axially chiral aryl monoaldehydes can be conveniently transformed into functionalized molecules, showing great potential as catalysts in organic chemistry.

关键词： chemistry. aldehydes chiral

First-Arrival Picking Method for Active Source Data with Ocean Bottom Seismometers Based on Spatial Waveform Variation Characteristics

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Journal of Ocean University of china 2024年第4期23卷 970-980页

作者： LIU Hongwei xing Lei ZHU Henghua ZHANG jin ZHANG jing LIU Huaishan Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdao 266100China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266071China College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001China Shandong Institute of Geological Survey Jinan 250014China

The precision and reliability of first-arrival picking are crucial for determining the accuracy of geological structure inversion using active source ocean bottom seismometer(OBS)refraction *** methods for first-arrival picking based on sample points are characterized by theoretical errors,especially in low-sampling-frequency OBS data because the travel time of seismic waves is not an integer multiple of the sampling *** this paper,a first-arrival picking method that utilizes the spatial waveform variation characteristics of active source OBS data is ***,the distribution law of theoretical error is examined;adjacent traces exhibit variation characteristics in their ***,a label cross-correlation superposition method for extracting highfrequency signals is presented to enhance the first-arrival picking *** from synthetic and field data verify that the proposed approach is robust,successfully overcomes the limitations of low sampling frequency,and achieves precise outcomes that are comparable with those of high-sampling-frequency data.

关键词： first-arrival picking spatial waveform variation label cross-correlation superposition method