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ON GENERALIZED KISSING NUMBERS OF CONVEX BODIES

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Acta Mathematica Scientia 2025年第1期45卷 72-95页

作者： Yiming LI Chuanming ZONG center for Applied Mathematics Tianjin UniversityTianjin300072China

In 1694,Gregory and Newton proposed the problem to determine the kissing number of a rigid material *** problem and its higher dimensional generalization have been studied by many mathematicians,including Minkowski,van der Waerden,Hadwiger,Swinnerton-Dyer,Watson,Levenshtein,Odlyzko,Sloane and *** this paper,we introduce and study a further generalization of the kissing numbers for convex bodies and obtain some exact results,in particular for balls in dimensions three,four and eight.

关键词： convex body generalized kissing number Eg lattice

Finite-Time Stability of Impulsive and Switched Hybrid Systems With Delay-Dependent Impulses

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 466-468页

作者： Taixiang Zhang Jinde Cao Mahmoud Abdel-Aty Ardak Kashkynbayev the School of Mathematics Southeast University IEEE the Deanship of Graduate Studies and Scientific Research Ahlia University the Jadara Research center Jadara University the Department of Mathematics Nazarbayev University

Dear Editor,This letter studies finite-time stability (FTS) of impulsive and switched hybrid systems with delay-dependent impulses. Some conditions, based on Lyapunov method, are proposed for ensuring FTS and estimating settling-time function (STF) of the hybrid *** switching dynamics are FTS and impulsive dynamics involve destabilizing delay-dependent impulses, the FTS is retained if the impulses occur infrequently.

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Fault Diagnosis for Railway Point Machines Using VMD Multi-Scale Permutation Entropy and ReliefF Based on Vibration Signals

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Chinese Journal of Electronics 2025年第1期34卷 204-211页

作者： Yongkui Sun Yuan Cao Peng Li Shuai Su National Engineering Research center of Rail Transportation Operation and Control System Beijing Jiaotong University School of Automation and Intelligence Beijing Jiaotong University Frontiers Science center for Smart High-speed Railway System Beijing Jiaotong University

The railway point machine plays an important part in railway systems. It is closely related to the safe operation of trains. Considering the advantages of vibration signals on anti-interference, this paper develops a novel vibration signal-based diagnosis approach for railway point machines. First, variational mode decomposition(VMD)is adopted for data preprocessing, which is verified more effective than empirical mode decomposition. Next, multiscale permutation entropy is extracted to characterize the fault features from multiple scales. Then ReliefF is utilized for feature selection, which can greatly decrease the feature dimension and improve the diagnosis accuracy. By experiment comparisons, the proposed approach performs best on diagnosis for railway point machines. The diagnosis accuracies on reverse-normal and normal-reverse processes are respectively 100% and 98.29%.

关键词： Vibrations Fault diagnosis Accuracy Data preprocessing Switches Feature extraction Rail transportation Entropy Maintenance Monitoring

Secure beamforming and deployment design for rate-splitting multiple access-based UAV communications

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Science China(Information Sciences) 2025年第1期68卷 342-356页

作者： Bing WANG Xiaofeng TAO Shujun HAN Huici WU Kai YANG Zhu HAN National Engineering Research center of Mobile Network Technologies Beijing University of Posts and Telecommunications Peng Cheng Laboratory Department of Electrical and Computer Engineering University of Houston

Rate-splitting multiple access(RSMA) has recently gained attention as a potential robust multiple access(MA)scheme for upcoming wireless networks. Given its ability to efficiently utilize wireless resources and design interference management strategies, it can be applied to unmanned aerial vehicle(UAV) networks to provide convenient services for large-scale access ground users. However, due to the line-of-sight(LoS) broadcast nature of UAV transmission, information is susceptible to eavesdropping in RSMA-based UAV networks. Moreover, the superposition of signals at the receiver in such networks becomes complicated. To cope with the challenge, we propose a two-user multi-input single-output(MISO) RSMA-based UAV secure transmission framework in downlink communication networks. In a passive eavesdropping scenario, our goal is to maximize the sum secrecy rate by optimizing the transmit beamforming and deployment location of the UAV-base station(UAV-BS),while considering quality-of-service(QoS) constraints, maximum transmit power, and flight space limitations. To address the non-convexity of the proposed problem, the optimization problem is first decoupled into two subproblems. Then, the successive convex approximation(SCA) method is employed to solve each subproblem using different propositions. In addition, an alternating optimization(AO)-based location RSMA(L-RSMA) beamforming algorithm is developed to implement joint optimization to obtain the suboptimal solution. Numerical results demonstrate that(1) the proposed L-RSMA scheme yields a28.97% higher sum secrecy rate than the baseline L-space division multiple access(SDMA) scheme;(2) the proposed L-RSMA scheme improves the security performance by 42.61% compared to the L-non-orthogonal multiple access(NOMA) scheme.

关键词： rate-splitting multiple access UAV communication precoding optimization deployment location physical layer security

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A dry-electrode enabled ECG-on-Chip with arrhythmia-aware data transmission

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Science China(Information Sciences) 2025年第2期68卷 338-353页

作者： Xinzi XU Yanxing SUO Yang ZHAO Peiyi ZHOU Xiao HAN Qiao CAI Min WANG Jiajun YUAN Liebin ZHAO Yongfu LI Guoxing WANG Yong LIAN Department of Micro-Nano Electronics and MoE Key Lab of Artificial Intelligence Shanghai Jiao Tong University Pediatric AI Clinical Application and Research center Shanghai Engineering Research Center of Intelligence Pediatrics (SERCIP)Child Health Advocacy InstituteShanghai Children's Medical CenterSchool of MedicineShanghai Jiao Tong University Shanghai Engineering Research center of Intelligence Pediatrics (SERCIP) Xin Hua Hospital Affiliate to Shanghai Jiao Tong University School of Medicine

Early detection and treatment of cardiovascular diseases(CVDs) can be significantly enhanced through the use of flexible wearable electrocardiogram(ECG) sensors, potentially reducing CVD-related mortality. This paper introduces an ECG-on-Chip(EoC) solution tailored for flexible ECG sensors, incorporating novel features to address common challenges in wearable ECG technology. The EoC integrates a chopper-stabilized capacitively-coupled instrumentation amplifier(CS-CCIA),ensuring a high common-mode rejection ratio(CMRR) and low noise performance. Performance is further boosted via a positive feedback loop(PFL) and a programmable gain amplifier(PGA) with shared on-chip calibration logic, which enhances input impedance and minimizes gain variability to ensure consistent algorithm performance. Additionally, a secondary chopping technique is employed to further reduce noise, achieving an input-referred noise level of 454 nVrms. The embedded algorithm within the EoC is designed to extract clinically meaningful features, facilitating robust real-time arrhythmia analysis. Fabricated using a 0.18 μm CMOS process, the EoC consumes 14.9 μW with a supply voltage of 1.2 V. The algorithm's efficacy has been validated over 0.4 million heartbeats, demonstrating a sensitivity of over 99.7% for R-peak detection and 98.3% for arrhythmia analysis. To demonstrate practical application, the EoC has been integrated with a commercial Bluetooth low energy(BLE)transceiver, forming a wireless arrhythmia monitoring sensor equipped with dry electrodes. This system consumes 292.04 μW in arrhythmia-aware transmission mode, supporting 13 days of operation with a 30 mAh thin-film battery.

关键词： ECG flexible dry electrodes analog front-end abnormality detection ASIC wireless transmission

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Toward long-life Zn anode using highly polar electrolyte additives

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Journal of Energy Chemistry 2025年第2期101卷 651-660页

作者： Nengbin Cai Hongming Chen Busheng Zhang Zijing Liu Xinbo He Dan Zhou Beijing Advanced Innovation center for Materials Genome Engineering University of Science and Technology Beijing Shunde Innovation School University of Science and Technology Beijing School of Textile Science and Engineering Wuyi University

Unstable Zn interface caused by rampant dendrite growth and parasitic side reactions always hinders the practical application of aqueous zinc metal batteries（AZMBs）,Herein,tyrosine（Tyr） with high molecular polarity was introduced into aqueous electrolyte to modulate the interfacial electrochemistry of Zn *** AZMBs,the positively charged side of Tyr can be well adsorbed on the surface of Zn anode to form a water-poor layer,and the exposed carboxylate side can be easily coordinated with Zn2+,favoring inducing uniform plating of Zn2+and inhibiting the occurrence of water-induced side *** in turn enable the achievement of highly stable Zn ***,the Zn anodes achieve outstanding cyclic stability(3000 h at 2 mA cm-2,2 mA h cm-2and 1300 h at 5 mA cm-2,5 mA h cm-2),high average Coulombic efficiency（99.4% over 3200 cycles）,and high depth of discharge（80% for 500 h）.Besides,the assembled Zn‖NaV3O8·1.5H2O full cells deliver remarkable capacity retention and ultra-long lifetime(61.8% over 6650 cycles at 5 A g-1) and enhanced rate capability(169 mA h g-1at 5 A g-1).The work may promote the design and deep understanding of electrolyte additives with high molecular polarity for high-performance AZMBs.

关键词： AZMBs Electrolyte additives Highly stable Zn anode Interfacial electrochemistry Tyr

Spastin and alsin protein interactome analyses begin to reveal key canonical pathways and suggest novel druggable targets

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Neural Regeneration Research 2025年第3期20卷 725-739页

作者： Benjamin R.Helmold Angela Ahrens Zachary Fitzgerald P.Hande Ozdinler Department of Neurology Feinberg School of MedicineNorthwestern UniversityChicagoILUSA center for Molecular Innovation and Drug Discovery Center for Developmental TherapeuticsChemistry of Life Processes InstituteNorthwestern UniversityEvanstonILUSA Mesulam center for Cognitive Neurology and Alzheimer’s Disease Feinberg School of MedicineNorthwestern UniversityChicagoILUSA Feinberg School of Medicine Les Turner ALS Center at Northwestern UniversityChicagoILUSA

Developing effective and long-term treatment strategies for rare and complex neurodegenerative diseases is challenging. One of the major roadblocks is the extensive heterogeneity among patients. This hinders understanding the underlying disease-causing mechanisms and building solutions that have implications for a broad spectrum of patients. One potential solution is to develop personalized medicine approaches based on strategies that target the most prevalent cellular events that are perturbed in patients. Especially in patients with a known genetic mutation, it may be possible to understand how these mutations contribute to problems that lead to neurodegeneration. Protein–protein interaction analyses offer great advantages for revealing how proteins interact, which cellular events are primarily involved in these interactions, and how they become affected when key genes are mutated in patients. This line of investigation also suggests novel druggable targets for patients with different mutations. Here, we focus on alsin and spastin, two proteins that are identified as “causative” for amyotrophic lateral sclerosis and hereditary spastic paraplegia, respectively, when mutated. Our review analyzes the protein interactome for alsin and spastin, the canonical pathways that are primarily important for each protein domain, as well as compounds that are either Food and Drug Administration–approved or are in active clinical trials concerning the affected cellular pathways. This line of research begins to pave the way for personalized medicine approaches that are desperately needed for rare neurodegenerative diseases that are complex and heterogeneous.

关键词： ALS2 alsin amyotrophic lateral sclerosis hereditary spastic paraplegia neurodegenerative diseases personalized medicine precision medicine protein interactome protein-protein interactions SPAST spastin

Exosomes:the next-generation therapeutic platform for ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1221-1235页

作者： Wenjing Yin Hongyin Ma Yang Qu Jiaxin Ren Yingying Sun Zhen-Ni Guo Yi Yang Stroke center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina Neuroscience Research center Department of NeurologyFirst Hospital of Jilin UniversityChangchunJilin ProvinceChina

Current therapeutic strategies for ischemic stroke fall short of the desired objective of neurological functional ***,there is an urgent need to develop new methods for the treatment of this *** are natural cell-derived vesicles that mediate signal transduction between cells under physiological and pathological *** have low immunogenicity,good stability,high delivery efficiency,and the ability to cross the blood–brain *** physiological properties of exosomes have the potential to lead to new breakthroughs in the treatment of ischemic *** rapid development of nanotechnology has advanced the application of engineered exosomes,which can effectively improve targeting ability,enhance therapeutic efficacy,and minimize the dosages *** in technology have also driven clinical translational research on *** this review,we describe the therapeutic effects of exosomes and their positive roles in current treatment strategies for ischemic stroke,including their antiinflammation,anti-apoptosis,autophagy-regulation,angiogenesis,neurogenesis,and glial scar formation reduction ***,it is worth noting that,despite their significant therapeutic potential,there remains a dearth of standardized characterization methods and efficient isolation techniques capable of producing highly purified *** optimization strategies should prioritize the exploration of suitable isolation techniques and the establishment of unified workflows to effectively harness exosomes for diagnostic or therapeutic applications in ischemic ***,our review aims to summarize our understanding of exosome-based treatment prospects in ischemic stroke and foster innovative ideas for the development of exosome-based therapies.

关键词： blood–brain barrier electroacupuncture engineering exercise exosomes ischemic stroke mesenchymal stem cells microglia neuroprotection stents

Spin freezing induced giant exchange bias in a doped Hund's metal

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 167-174页

作者： Shunjiao Li Dan Zhao Jian Li Baolei Kang Min Shan Yanbing Zhou Xuyang Li Tao Wu Xianhui Chen Hefei National Research center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Strongly Coupled Quantum Matter Physics Department of PhysicsUniversity of Science and Technology of ChinaHefei 230026China CAS center for Excellence in Superconducting Electronics(CENSE) Shanghai 200050China Collaborative Innovation center of Advanced Microstructures Nanjing UniversityNanjing 210093China Hefei National Laboratory University of Science and Technology of ChinaHefei 230088China

Exchange bias(EB)is a fundamental phenomenon in widespread information ***,a comprehensive understanding of its microscopic origin remains a great *** key issue in the debate is the role of frustration and disorder in the EB mechanism,which motivates the exploration of the EB effect in spin glass(SG)***,in the SG state of Crdoped Hund's metal CsFe_(2)As_(2),we discover a giant EB effect with a maximum bias field of -2 T,which is almost two orders of magnitude larger than that of traditional alloy *** results indicate that the giant EB effect should originate from the exchange interactions at the natural boundaries between the tunable ferromagnetic-like(FM)regions around Cr dopants and the SG matrix,via which the FM spins are strongly pinned by the frozen spins in the SG *** addition,the temperaturedependent and cooling-field-dependent EB behaviors could be interpreted well by the SG model with frustrated FM/SG boundaries,which provides an intuitive and explicit understanding of the impact of glassy parameters on the EB *** these results suggest that the correlated metals are promising directions for exploring the EB effect in the SG state.

关键词： Hund's metal spin glass exchange bias iron-based superconductor

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