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Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao Chen xie Liu Changqing Xu Da-Jian Wu Ying Cheng Xiao-Jun Liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang xie Wenjiao Zhou Huan Tong Dawen Yang Anjia Zhang Yuan Wu Xiping Song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

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Stiffness-tunable biomaterials provide a good extracellular matrix environment for axon growth and regeneration

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Neural Regeneration Research 2025年第5期20卷 1364-1376页

作者： Ronglin Han Lanxin Luo Caiyan Wei Yaru Qiao Jiming xie Xianchao Pan Juan Xing Department of Pathophysiology School of Basic Medical SciencesSouthwest Medical UniversityLuzhouSichuan ProvinceChina Department of Medicinal Chemistry School of PharmacySouthwest Medical UniversityLuzhouSichuan ProvinceChina

Neuronal growth, extension, branching, and formation of neural networks are markedly influenced by the extracellular matrix—a complex network composed of proteins and carbohydrates secreted by cells. In addition to providing physical support for cells, the extracellular matrix also conveys critical mechanical stiffness cues. During the development of the nervous system, extracellular matrix stiffness plays a central role in guiding neuronal growth, particularly in the context of axonal extension, which is crucial for the formation of neural networks. In neural tissue engineering, manipulation of biomaterial stiffness is a promising strategy to provide a permissive environment for the repair and regeneration of injured nervous tissue. Recent research has fine-tuned synthetic biomaterials to fabricate scaffolds that closely replicate the stiffness profiles observed in the nervous system. In this review, we highlight the molecular mechanisms by which extracellular matrix stiffness regulates axonal growth and regeneration. We highlight the progress made in the development of stiffness-tunable biomaterials to emulate in vivo extracellular matrix environments, with an emphasis on their application in neural repair and regeneration, along with a discussion of the current limitations and future prospects. The exploration and optimization of the stiffness-tunable biomaterials has the potential to markedly advance the development of neural tissue engineering.

关键词： alginate axon growth biomaterials extracellular matrix neural repair neurons neuroregeneration polyacrylamide polydimethylsiloxane stiffness

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Formation mechanism of deep natural hydrogen in the Sichuan Basin

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Science China Earth Sciences 2025年

作者： Xiaomei WANG Kun HE Chunlong YANG Hao xie Xiaobo WANG Yitong LYU linfeng xie Shuichang ZHANG Research Institute of Petroleum Exploration & Development PetroChina Key Laboratory of Petroleum Geochemistry China National Petroleum Corporation International Center for Isotope Effects Research School of Earth Science and Engineering Nanjing University

As a potential renewable and clean energy source,the distribution and exploration prospects of natural hydrogen have garnered widespread ***,the limitations in understanding the formation mechanisms and accumulation patterns of underground natural hydrogen have significantly constrained its efficient exploration and *** study reports H2content and isotopes in natural gas from deep formations in sedimentary basins through geochemical analysis of 58 conventional gas samples from the Sinian to Triassic strata in the central Sichuan *** discovered that H2content in deep natural gas in central Sichuan generally exceeds 0.1%,with a maximum of 1.6%,and hydrogen isotopes (δ2HH2) range from-850‰to-586‰.Analysis of the geological conditions,hydrogen generation mechanisms,and isotope fractionation characteristics in the study area confirms that microbial fermentation or in-situ organic matter cracking are not effective pathways for deep *** with helium content and isotope analysis of the natural gas,it is inferred that the volcanic basement in the central Sichuan area is the potential source rock for natural H2in the Sinian to Triassic ***,H2originates from the radiolysis of water and hydrothermal reactions of Fe（II） in the basement ***,a diffusion fractionation model reveals significant isotope fractionation during the migration and accumulation of deep H2into sedimentary reservoirs,which lead to anomalously light δ2HH2in deep natural gas in central *** indicates that the underground natural hydrogen accumulation is in a long-term dynamic process,with simultaneous H2accumulation and dissipation in the gas *** research not only elucidates the formation mechanism of deep H2but also provides insights for the resource potential of natural hydrogen in sedimentary basins.

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Actively tunable electromagnetically induced transparency in hybrid Dirac-VO2 metamaterials

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Optoelectronics Letters 2025年第1期21卷 13-20页

作者： DI Ke xie Meng XIA Huarong CHENG Anyu LIU Yu DU Jiajia Department of Optoelectronic Engineering Chongqing University of Post and Telecommunications Chongqing Key Laboratory of Autonomous Navigation and Microsystem Chongqing University of Posts and Telecommunications Department of Automation Chongqing University of Post and Telecommunications

In this paper, we present a metamaterial structure of Dirac and vanadium dioxide（VO2） and investigate its optical properties using the finite-difference time-domain（FDTD） technique. Using the phase transition feature of VO2, the design can realize active tuning of the plasmon induced transparency（PIT） effect at terahertz frequency, thereby converting from a single PIT to a double-PIT. When VO2is in the insulating state, the structure is symmetric to obtain a single-band PIT effect. When VO2is in the metallic state, the structure turns asymmetric to realize a dual-band PIT effect. This design provides a reference direction for the design of actively tunable metamaterials. Additionally, it is discovered that the transparent window's resonant frequency and the Fermi level in this structure have a somewhat linear relationship. In addition, the structure achieves superior refractive index sensitivity in the terahertz band, surpassing 1 THz/RIU. Consequently, the design exhibits encouraging potential for application in refractive index sensors and optical switches.

关键词： Transparency

Deep learning identification of novel autophagic protein-protein interactions and experimental validation of Beclin 2-Ubiquilin 1 axis in triple-negative breast cancer

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Oncology Research 2025年第1期33卷 67-81页

作者： XIANG LI WENKE JIN LIFENG WU HUAN WANG XIN xie WEI HUANG BO LIU State Key Laboratory of Southwestern Chinese Medicine Resources School of Pharmacy and College of Medical TechnologyChengdu University of Traditional Chinese MedicineChengdu611137China Department of Biotherapy Cancer Center and State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu610041China

Background:Triple-negative breast cancer(TNBC),characterized by its lack of traditional hormone receptors and HER2,presents a significant challenge in oncology due to its poor response to conventional *** is an important process for maintaining cellular homeostasis,and there are currently autophagy biomarkers that play an effective role in the clinical treatment of *** contrast to targeting protein activity,intervention with proteinprotein interaction(PPI)can avoid unrelated crosstalk and regulate the autophagy process with minimal interference ***:Here,we employed Naive Bayes,Decision Tree,and k-Nearest Neighbors to elucidate the complex PPI network associated with autophagy in TNBC,aiming to uncover novel therapeutic ***,the candidate proteins interacting with Beclin 2 were initially screened in MDA-MB-231 cells using Beclin 2 as bait protein by immunoprecipitation-mass spectrometry assay,and the interaction relationship was verified by molecular docking and CO-IP experiments after *** formation,cellular immunofluorescence,cell scratch and 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)tests were used to predict the clinical therapeutic effects of manipulating candidate ***:By developing three PPI classification models and analyzing over 13,000 datasets,we identified 3733 previously unknown autophagy-related *** network analysis revealed the central role of Beclin 2 in autophagy regulation,uncovering its interactions with 39 newly identified ***,the CO-IP studies identified the substantial interaction between Beclin 2 and Ubiquilin 1,which was anticipated by our model and discovered in immunoprecipitation-mass spectrometry assay ***,in vitro investigations showed that overexpressing Beclin 2 increased Ubiquilin 1,promoted autophagy-dependent cell death,and inhibited proliferation and metastasis in MDA-MB-231 ***:This study not

关键词： Triple-negative breast cancer(TNBC) Autophagy Protein-protein interactions(PPI) Artificial intelligence(AI) Beclin 2 Ubiquilin 1

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期68卷 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.

关键词： gold catalysis peptide alkylation C-C coupling radical

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Harnessing the Streptomyces-originating type I-E CRISPR/Cas system for efficient genome editing in Streptomyces

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Science China Life Sciences 2025年

作者： Yuhui xie Xiaoyan Liu Tingting Wu Yunzi Luo Frontiers Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (Ministry of Education) School of Chemical Engineering and TechnologyTianjin University Department of Gastroenterology State Key Laboratory of BiotherapyWest China HospitalSichuan University Georgia Tech Shenzhen Institute Tianjin University Haihe Laboratory of Sustainable Chemical Transformations

Since their discovery,CRISPR/Cas systems have significantly expanded the genetic toolbox,aiding in the exploration and enhanced production of natural products across various *** these,class 2 CRISPR/Cas systems are simpler and more broadly used,but they frequently fail to function effectively in many Streptomyces *** this study,we present an engineered class 1 type I CRISPR/Cas system derived from Streptomyces avermitilis,which enables efficient gene editing in phylogenetically distant Streptomyces *** a plasmid interference assay,we identified the effective protospacer adjacent motif as 5′-AAN-3′.Utilizing this system,we achieved targeted chromosomal deletions ranging from 8 bp to 100 kb,with efficiencies exceeding 92%.We further utilized this system to insert DNA fragments into different Streptomyces genomes,facilitating the heterologous expression of exogenous genes and the activation of endogenous natural product biosynthetic gene ***,we established a type I CRISPR/Cas-based gene-editing methodology that significantly advances the exploration of Streptomyces,known for their rich natural product *** is the first report of a gene editing tool developed based on the endogenous class 1 type I CRISPR/Cas system in Streptomyces *** work enriches the Streptomyces gene manipulation toolbox and advances the discovery of valuable natural products within these organisms.

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Theoretical Study on the Dehydrogenation Reaction of H_2S by VS^+ (~3Σ^-)

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1111-1116页

作者： GAO Shu-lin LIU Zheng-mei xie Xiao-Guang Department of Chemistry Yunnan University Kunming 650091 China School of Physics and Chemistry Guizhou Normal University Guiyang 550001 China

The dehydrogenation reaction of H2S by the ^3Σ^- ground state of VS^＋： VS^＋＋ H2S → VS2^＋＋ H2 has been studied by using Density Functional Theory （DPT） at the B3LYP/DZVP level. It is found that the reaction proceeds along two possible pathways （A and B） yielding two isomer dehydrogenation products VS2^＋-1 （^3B2） and VS2^＋-2 （^3A1）, respectively. For both pathways, the reaction has a two-step-reaction mechanism that involves the migration of two hydrogen atoms from S2 to V^＋, respectively. The migration of the second hydrogen via TS3 and that of the first via TS4 are the rate-determining steps for pathways A and B, respectively. The activation energy is 17.4 kcal/mol for pathway A and 22.8 kcal/mol for pathway B relative to the reactants. The calculated reaction heat of 9.9 kcal/mol indicates the endothermicity of pathway A and that of -11.9 kcal/mol suggests the exothermicity of pathway B.

关键词： density functional theory cationic transition metal sulfide,dehydrogenation reaction reaction mechanism

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