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Ultra-high-temperature application of MXene: Stabilization of 2D Ti_(3)C_(2)T_(x) for cross-scale strengthening and toughening of 3D TiC

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Journal of Advanced Ceramics 2024年第1期13卷 1-10页

作者： Lu Liu Guobing ying Quanguo Jiang Dong Wen Peng Wang Meng wu Ziying Ji Yongting Zheng Xiang Wang Department of Materials Science and Engineering College of Mechanics and MaterialsHohai UniversityNanjing 211100China Key Laboratory of Superlight Materials&Surface Technology Ministry of EducationHarbin Engineering UniversityHarbin 150001China Shenzhen Key Laboratory for Advanced Materials School of Materials Science and EngineeringHarbin Institute of Technology(Shenzhen)Shenzhen 518055China Center for Composite Materials and Structures Harbin Institute of TechnologyHarbin 150001China

Transition metal carbide/nitride cores within MXenes make them considerably useful for ultra-high-temperature reinforcement.However,extensive research on Ti_(3)C_(2)T_(x) MXene has revealed its tendency to undergo a phase transition to TiCy at temperatures above 800℃due to high activity of a superficial Ti atomic layer.Herein,spark plasma sintering of Ti_(3)C_(2)T_(x) and TiC is performed to prevent the Ti_(3)C_(2)T_(x) phase transition at temperatures up to 1900℃through the fabrication of composites at a pressure of 50 MPa.Using a focused ion beam scanning electron microscope to separate layered substances in the composites and examining selected area diffraction spots in a transmission electron microscope enabled identification of non-phase-transitioned MXene.First-principles calculations based on density functional theory indicated the formation of strong chemical bonding interfaces between Ti_(3)C_(2)T_(x) and TiC,which imposed a stability constraint on the Ti atomic layer at the Ti_(3)C_(2)T_(x) surface.Mechanical performance tests,such as three-point bending and fracture toughness analysis,demonstrated that the addition of Ti_(3)C_(2)T_(x) can effectively improve the cross-scale strengthening and toughening of the TiC matrix,providing a new path for designing and developing two-dimensional(2D)carbides cross-scale-enhanced three-dimensional(3D)carbides with the same elements relying on a wide variety of MXenes.

关键词： MXene ultra-high-temperature phase stability interface bonding cross-scale strengthening and toughening structural ceramic composites

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Tunable quantum dots in monolithic Fabry-Perot microcavities for high-performance single-photon sources

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Light(Science & Applications) 2024年第2期13卷 325-332页

作者： Jiawei Yang Yan Chen Zhixuan Rao Ziyang Zheng Changkun Song Yujie Chen Kaili Xiong Pingxing Chen Chaofan Zhang Wei wu ying Yu Siyuan Yu State Key Laboratory of Optoelectronic Materials and Technologies School of Electronics and Information TechnologySun Yat-Sen UniversityGuangzhou 510006China Institute for Quantum Science and Technology College of ScienceNational University of Defense TechnologyChangsha 410073China College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China Hunan Key Laboratory of Quantum Information Mechanism and Technology National University of Defense TechnologyChangsha 410073 HunanChina Hefei National Laboratory Hefei 230088China

Cavity-enhanced single quantum dots(QDs)are the main approach towards ultra-high-performance solid-state quantum light sources for scalable photonic quantum technologies.Nevertheless,harnessing the Purcell effect requires precise spectral and spatial alignment of the QDs’emission with the cavity mode,which is challenging for most cavities.Here we have successfully integrated miniaturized Fabry-Perot microcavities with a piezoelectric actuator,and demonstrated a bright single-photon source derived from a deterministically coupled QD within this microcavity.Leveraging the cavity-membrane structures,we have achieved large spectral tunability via strain tuning.On resonance,a high Purcell factor of~9 is attained.The source delivers single photons with simultaneous high extraction efficiency of 0.58,high purity of 0.956(2)and high indistinguishability of 0.922(4).Together with its compact footprint,our scheme facilitates the scalable integration of indistinguishable quantum light sources on-chip,therefore removing a major barrier to the development of solid-state quantum information platforms based on QDs.

关键词： quantum removing purity

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Federated Dynamic Client Selection for Fairness Guarantee in Heterogeneous Edge Computing

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Journal of Computer Science & Technology 2024年第1期39卷 139-158页

作者：毛莺池沈莉娟吴俊平萍吴杰 Key Laboratory of Water Big Data Technology of Ministry of Water Resources Hohai UniversityNanjing 211100China College of Computer and Information Hohai UniversityNanjing 211100China Center of Networked Computing Temple UniversityPhiladelphiaPA 19122-6096U.S.A

Federated learning has emerged as a distributed learning paradigm by training at each client and aggregat-ing at a parameter server.System heterogeneity hinders stragglers from responding to the server in time with huge com-munication costs.Although client grouping in federated learning can solve the straggler problem,the stochastic selection strategy in client grouping neglects the impact of data distribution within each group.Besides,current client grouping ap-proaches make clients suffer unfair participation,leading to biased performances for different clients.In order to guaran-tee the fairness of client participation and mitigate biased local performances,we propose a federated dynamic client selec-tion method based on data representativity(FedSDR).FedSDR clusters clients into groups correlated with their own lo-cal computational efficiency.To estimate the significance of client datasets,we design a novel data representativity evalua-tion scheme based on local data distribution.Furthermore,the two most representative clients in each group are selected to optimize the global model.Finally,the DYNAMIC-SELECT algorithm updates local computational efficiency and data representativity states to regroup clients after periodic average aggregation.Evaluations on real datasets show that FedS-DR improves client participation by 27.4%,37.9%,and 23.3%compared with FedAvg,TiFL,and FedSS,respectively,tak-ing fairness into account in federated learning.In addition,FedSDR surpasses FedAvg,FedGS,and FedMS by 21.32%,20.4%,and 6.90%,respectively,in local test accuracy variance,balancing the performance bias of the global model across clients.

关键词： federated learning fairness computational efficiency data distribution client selection client grouping

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Construction of plum-branch-like CoSe2@N-Doped carbon/carbon fiber with dual protective mechanisms for enhanced lithium storage

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Progress in Natural Science:Materials International 2024年第3期34卷 495-502页

作者： ying Wang Ming Zhang Lei Chen Yanjuan Li Qingqing Wang Xiaobin wu Lingdi Shen Xiao Yan School of Chemistry & Materials Science Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials Jiangsu Normal University

Cobalt selenide（CoSe2） emerges as a highly promising anode material for lithium-ion batteries（LIBs） owing to its high theoretical capacity and cost-effectiveness. Despite these merits, its practical utilization faces challenges stemming from substantial volume fluctuations and limited electronic conductivity. To tackle these issues, a plumbranch-like structure of CoSe2@N-doped carbon that embedded in one-dimensional N-doped carbon fibers（CoSe2@NC/CFs）, is successfully synthesized through an in-situ confinement method. Well-defined CoSe2@NC nanoparticles, featuring diameters between 20～30 nm, are uniformly dispersed on both the inner and outer surfaces of the carbon fibers. The distinctive architecture of CoSe2@NC/CFs ensures an increased number of active sites, elevated electronic conductivity, alleviated volume expansion, and accelerated reaction kinetics.Consequently, the CoSe2@NC/CFs exhibits remarkable cycling performance and exceptional rate capability.Operating at a current density of 1000 mA g-1, the CoSe2@NC/CFs anode sustains a capacity of 664 mA h g-1with no obvious capacity decay over 500 cycles. Even at a high current density of 5000 mA g-1, it maintains a capacity of 445 mA h g-1with a mere 0.02 % capacity decay per cycle. This study introduces a novel approach to anode material design, showcasing significant advancements in lithium-ion battery technology.

关键词： Carbon fiber Electrochemical performances Electrode Lithium-ion battery Metal-selenide

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Importance of periphytic biofilms for carbon cycling in paddy fields:A review

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Pedosphere 2024年第1期34卷 36-43页

作者： Lei ZHOU Yonghong wu Junzhuo LIU Pengfei SUN ying XU Jan DOLFING Robert GMSPENCER Erik JEPPESEN State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China Zigui Three Gorges Reservoir Ecosystem Observation and Research Station of Ministry of Water Resources of the People's Republic of ChinaYichang 443605China College of Nanjing University of Chinese Academy of SciencesNanjing 211135China Faculty of Energy and Environment Northumbria UniversityNewcastle upon Tyne NE18QHUK Department of Earth Ocean and Atmospheric ScienceFlorida State UniversityTallahassee FL 32306USA Department of Ecoscience&Centre for Water Technology(WATEC) Aarhus UniversityAarhus DK-8000Denmark Sino-Danish Centre for Education and Research Beijing 100049China Limnology Laboratory Department of Biological Sciences and Centre for Ecosystem Research and Implementation(EKOSAM)Middle East Technical UniversityAnkara 06800Turkiye Institute of Marine Sciences Middle East Technical UniversityMersin 33731Turkiye

Paddy fields play an important role in global carbon(C) cycling and are an important source of methane(CH_(4)) emissions. Insights into the processes influencing the dynamics of soil organic C(SOC) in paddy fields are essential for maintaining global soil C stocks and mitigating climate change. Periphytic biofilms composed of microalgae, bacteria, and other microorganisms are ubiquitous in paddy fields, where they directly mediate the transfer of elements at the soil-water interface. However, their contributions to C turnover and exchange have been largely neglected. Periphytic biofilms affect and participate in soil C dynamics by altering both abiotic(e.g., pH and redox potential) and biotic conditions(e.g., microbial community composition and metabolism). This review summarizes the contributions of periphytic biofilms to soil C cycling processes, including carbon dioxide fixation, SOC mineralization, and CH_(4) emissions. Future research should be focused on: i) the mechanisms underlying periphytic biofilm-induced C fixation and turnover and ii) quantifying the contributions of periphytic biofilms to soil C uptake, stabilization, and sequestration in paddy fields.

关键词： carbon fixation carbon mineralization carbon sequestration methane emission microbial aggregates soil organic carbon

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Unsynchronized butyrophilin molecules dictate cancer cell evasion of Vγ9Vδ2 T-cell killing

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Cellular & Molecular Immunology 2024年第4期21卷 362-373页

作者： Zeguang wu Qiezhong Lamao Meichao Gu Xuanxuan Jin ying Liu Feng Tian ying Yu Pengfei Yuan Shuaixin Gao Thomas S.Fulford Adam P.Uldrich Catherine C.L Wong Wensheng Wei Biomedical Pioneering Innovation Center Peking-Tsinghua Center for Life SciencesPeking University Genome Editing Research CenterState Key Laboratory of Protein and Plant Gene ResearchSchool of Life SciencesPeking University100871BeijingChina EdiGene Inc. Life Science ParkChangping District102206BeijingChina Center for Precision Medicine Multi-Omics Research Peking University Health Science CenterPeking University100191BeijingChina Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity The University of MelbourneParkvilleVIC3010Australia Cancer Immunology Program Peter MacCallum Cancer CentreMelbourneVICAustralia State Key Laboratory for Complex Severe and Rare DiseasesClinical Research InstitutePeking Union Medical College HospitalChinese Academy of Medical Science&Peking Union Medical CollegePeking-Tsinghua Center for Life Sciences100871BeijingChina

Vγ9Vδ2 T cells are specialized effector cells that have gained prominence as immunotherapy agents due to their ability to target and kill cells with altered pyrophosphate metabolites.In our effort to understand how cancer cells evade the cell-killing activity of Vγ9Vδ2 T cells,we performed a comprehensive genome-scale CRISPR screening of cancer cells.We found that four molecules belonging to the butyrophilin(BTN)family,specifically BTN2A1,BTN3A1,BTN3A2,and BTN3A3,are critically important and play unique,nonoverlapping roles in facilitating the destruction of cancer cells by primary Vγ9Vδ2 T cells.The coordinated function of these BTN molecules was driven by synchronized gene expression,which was regulated by IFN-γsignaling and the RFX complex.Additionally,an enzyme called QPCTL was shown to play a key role in modifying the N-terminal glutamine of these BTN proteins and was found to be a crucial factor in Vγ9Vδ2 T cell killing of cancer cells.Through our research,we offer a detailed overview of the functional genomic mechanisms that underlie how cancer cells escape Vγ9Vδ2 T cells.Moreover,our findings shed light on the importance of the harmonized expression and function of gene family members in modulating T-cell activity.

关键词： Butyrophilin Vγ9Vδ2 T-cell Cancer-specific immune evasion Glutaminyl-peptide cyclotransferase-like Pyrophosphate metabolite Immunotherapy

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Omental fibroma combined with right indirect inguinal hernia masquerades as a scrotal tumor: A case report

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World Journal of Clinical Cases 2024年第5期12卷 988-994页

作者： Ping Zhou Chan-Hui Jin ying Shi Guo-Qing Ma Wen-Hao wu Yu Wang Kun Cai wu-Feng Fan Tian-Bao Wang Department of Gastrointestinal Surgery South China Hospital of Shenzhen UniversityShenzhen 518000Guangdong ProvinceChina

BACKGROUND The most common causes of scrotal enlargement in patients include primary tumor of the scrotum,inflammation,hydrocele of the tunica vaginalis,and indirect inguinal hernia;scrotal enlargement caused by external tumors of the scrotum is rare.The patient had both a greater omentum tumor and an inguinal hernia,and the tumor protruded into the scrotum through the hernia sac,which is even rarer.Moreover,omental tumors are mostly metastatic,and primary omental fibroma is rare.CASE SUMMARY Here,we report a rare case of a 25-year-old young man with scrotal enlargement and pain for 3 months.Preoperative examination and multidisciplinary discu-ssions considered intra-abdominal tumor displacement and inguinal hernia,and intraoperative exploration confirmed that the greater omentum tumor protruded into the scrotum.Therefore,tumor resection and tension-free inguinal hernia repair were performed.The final diagnosis was benign fibroma of the greater omentum accompanied by an indirect inguinal hernia.CONCLUSION This unusual presentation of a common inguinal hernia disease illustrates the necessity of performing detailed history taking,physical examination,and imaging before surgery.

关键词： Hernia Indirect inguinal hernia Fibroma Omental tumor Scrotal tumor Greater omentum Case report

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Design of high frequency broadband low insertion loss SAW filter at 3.5 GHz

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The Journal of China Universities of Posts and Telecommunications 2024年第2期31卷 55-61页

作者： Wang Wei Zhang ying Wang Fang wu Hao Ding Hui Xia Xu Wang Guanyu Xie yingtao School of Optoelectronics Engineering/International Semiconductor College Chongqing University of Posts and TelecommunicationsChongqing 400065China

With the wide application of the fifth-generation mobile communication system(5G)technology,wireless communication equipment tends to develop in miniaturization,high frequency,and low loss.In this paper,a surface acoustic wave(SAW)filter with a center frequency of 3.5 GHz was designed.Firstly,the acoustic waveguide structure of the longitudinal leaky SAW(LLSAW)excitation is determined,and the two-dimensional(2D)theoretical model of the device is established by COMSOL Multiphysics.Secondly,the influence of electrode parameters on the performance of the device is studied,and the electrode parameters are optimized on this basis.By setting the device structure parameters reasonably,the spurious in the passband can be effectively suppressed.Finally,the center frequency of the mirror T-structure LLSAW filter is 3.536 GHz,the insertion loss is-1.414 dB,the bandwidth of-3 dB is 276 MHz,and the out-of-band rejection is greater than-30 dB.

关键词： surface acoustic wave(SAW) electrode spurious response mirror T-structure

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Migratable Power System Transient Stability AssessmentMethod Based on Improved XGBoost

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Energy Engineering 2024年第7期121卷 1847-1863页

作者： ying Qu Jinhao Wang Xueting Cheng Jie Hao Weiru Wang Zhewen Niu Yuxiang wu Electric Power Science Research Institute State Grid Shanxi Electric Power CompanyTaiyuan030000China Department of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuan030024China

The data-driven transient stability assessment(TSA)of power systems can predict online real-time prediction by learning the temporal features before and after faults.However,the accuracy of the assessment is limited by the quality of the data and has weak transferability.Based on this,this paper proposes a method for TSA of power systems based on an improved extreme gradient boosting(XGBoost)model.Firstly,the gradient detection method is employed to remove noise interference while maintaining the original time series trend.On this basis,a focal loss function is introduced to guide the training of theXGBoostmodel,enhancing the deep exploration of minority class samples to improve the accuracy of the model evaluation.Furthermore,to improve the generalization ability of the evaluation model,a transfer learning method based on model parameters and sample augmentation is proposed.The simulation analysis on the IEEE 39-bus system demonstrates that the proposed method,compared to the traditional machine learning-based transient stability assessment approach,achieves an average improvement of 2.16%in evaluation accuracy.Specifically,under scenarios involving changes in topology structure and operating conditions,the accuracy is enhanced by 3.65%and 3.11%,respectively.Moreover,the model updating efficiency is enhanced by 14–15 times,indicating the model’s transferable and adaptive capabilities across multiple scenarios.

关键词： Transient stability assessment data-driven segmented focusing approximation portability

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Early colorectal cancer screening–no time to lose

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World Journal of Gastroenterology 2024年第23期30卷 2959-2963页

作者： ying Wang Zheng-Long wu Yi-Gang Wang Hui Wang Xiao-Yuan Jia College of Life Sciences and Medicine Zhejiang Sci-Tech UniversityHangzhou 310018Zhejiang ProvinceChina Department of Oncology Zhejiang Xiaoshan HospitalHangzhou 310018Zhejiang ProvinceChina

In this editorial,we comment on the article entitled“Stage at diagnosis of colorectal cancer through diagnostic route:Who should be screened?”by Agatsuma et al.Colorectal cancer(CRC)is emerging as an important health issue as its incidence continues to rise globally,adversely affecting the quality of life.Although the public has become more aware of CRC prevention,most patients lack screening awareness.Some poor lifestyle practices can lead to CRC and symptoms can appear in the early stages of CRC.However,due to the lack of awareness of the disease,most of the CRC patients are diagnosed already at an advanced stage and have a poor prognosis.

关键词： Colorectal cancer The immunochemical fecal occult blood test Diagnostic route Cancer screening Stage at diagnosis

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