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Design and prototyping of the readout electronics for the transition radiation detector in the high energy cosmic radiation detection facility

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Nuclear Science and Techniques 2024年第4期35卷 189-199页

作者： Jie-Yu Zhu Yang-Zhou Su Hai-Bo Yang Fen-Hua Lu Yan Yang Xi-Wen Liu Ping Wei Shu-Cai Wan Hao-Qing Xie Xian-Qin Li Cong Dai Hui-Jun Hu Hong-Bang Liu Shu-Wen Tang Cheng-Xin Zhao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China

The high energy cosmic-radiation detection(HERD)facility is planned to launch in 2027 and scheduled to be installed on the China Space *** serves as a dark matter particle detector,a cosmic ray instrument,and an observatory for high-energy gamma rays.A transition radiation detector placed on one of its lateral sides serves dual purpose,(ⅰ)calibrating HERD's electromagnetic calorimeter in the TeV energy range,and(ⅱ)serving as an independent detector for high-energy gamma *** this paper,the prototype readout electronics design of the transition radiation detector is demonstrated,which aims to accurately measure the charge of the anodes using the SAMPA application specific integrated circuit *** electronic performance of the prototype system is evaluated in terms of noise,linearity,and *** the presented design,each electronic channel can achieve a dynamic range of 0–100 fC,the RMS noise level not exceeding 0.15 fC,and the integral nonlinearity was<0.2%.To further verify the readout electronic performance,a joint test with the detector was carried out,and the results show that the prototype system can satisfy the requirements of the detector's scientific goals.

关键词： HERD Dark matter particle detection TRD Readout electronics SAMPA Data acquisition Performance test

Stereoselectiveα-Glycosylation with GlcN_(3)Donors Enabled Collective Syntheses of Acinetobacter baumannii Capsular Polysaccharides K43,K47 and K88 Repeating Units

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Chinese Journal of Chemistry 2024年第14期42卷 1593-1598页

作者： Kunxiu Shou Shanshan Liu Yunqin Zhang Guozhi Xiao State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyUniversity of Chinese Academy of SciencesChinese Academy of SciencesKunmingYunnan650201 China

Collective syntheses of *** CPS K43,K47 and K88 repeating units have been accomplished via a newα-glycosylation method with GlcN_(3) as donors,which features:1)mild reaction conditions,2)good to high yields,3)excellent *** synthetic route also highlights an orthogonal one-pot coupling strategy on the basis of glycosyl ortho-(1-phenylvinyl)benzoates for stereoselective constructions of both 1,2-trans and 1,2-cis glycosidic bonds,precluding the issues of aglycone transfer.

关键词： A baumanni CPS α-Glycosylation method One-pot glycosylation 1,2-GlcN bonds Glycosyl ortho-(1-phenylvinyl)benzoates Carbohydrates Oligosaccharides Total synthesis

2D Ca/Nb-based perovskite oxide with Ta doping as highly efficient H_(2)O_(2)synthesis catalyst

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Nano Research 2024年第6期17卷 4934-4942页

作者： Xingchen Yang Yang Gao Xiaohui Xu Wenqiang Xu Denghui Wang Bin Luo Dong Liu Tao Liang Bin Wang cas Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Nanomaterials Centre School of Chemical Engineering and Australian Institute for Bioengineering and Nanotechnologythe University of QueenslandSt LuciaQLD 4072Australia State Key Laboratory of Organic–Inorganic Composites College of Chemical EngineeringCollege of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China State Key Lab of Silicon Materials Zhejiang UniversityHangzhou 310027China

Perovskite oxides(POs)are emerging as a class of highly efficient catalysts for reducing oxygen to H_(2)*** a rich variety of POs-based catalysts have been developed by tuning the complex composition,a highly efficient PO catalyst that is able to alter the reaction pathway from a 4e−process to a 2e−process for H_(2)O_(2)production has rarely been *** modified the structure and composition of a Ca-and Nb-based PO material by realizing a uniform two-dimensional(2D)morphology and varied Ta doping,resulting in the 2D Ca_(2)Nb_(3−x)Ta_(x)O_(10)−(x=0,0.5,1,and 1.5)monolayer *** obtained catalysts exhibit a dominant 2e−pathway and show exceptional H_(2)O_(2)production *** typical Ca_(2)Nb_(2.5)Ta_(0.5)O_(10)−nanoflakes showed an onset potential of 0.735 V *** hydrogen electrode(RHE),a remarkably high selectivity over 95%across a wide range of 0.3-0.7 V,an impressively high Faradaic efficiency of 94%,and a notable H_(2)O_(2)productivity of 1571 mmol·gcat^(−1)·h^(−1).These findings highlight the great potential of 2D perovskite oxide nanoflakes as advanced electrocatalysts for 2e−oxygen reduction reaction.

关键词： perovskite oxide H_(2)O_(2) two-electron oxygen reduction reaction catalyst Ca_(2)Nb_(3-x)Ta_(x)O_(10)-nanoflakes

Learning Sequential and Structural Dependencies Between Nucleotides for RNA N6-Methyladenosine Site Identification

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2123-2134页

作者： Guodong Li Bowei Zhao Xiaorui Su Dongxu Li Yue Yang Zhi Zeng Lun Hu Xinjiang Technical Institute of Physics and Chemistry Chinese Academy of ScienceUrumqi 830011China College of Computer Xi’an Jiaotong UniversityXi’an 710049China IEEE

N6-methyladenosine(m6A)is an important RNA methylation modification involved in regulating diverse biological processes across multiple ***,the identification of m6A modification sites provides valuable insight into the biological mechanisms of complex diseases at the post-transcriptional *** a variety of identification algorithms have been proposed recently,most of them capture the features of m6A modification sites by focusing on the sequential dependencies of nucleotides at different positions in RNA sequences,while ignoring the structural dependencies of nucleotides in their threedimensional *** overcome this issue,we propose a cross-species end-to-end deep learning model,namely CR-NSSD,which conduct a cross-domain representation learning process integrating nucleotide structural and sequential dependencies for RNA m6A site ***,CR-NSSD first obtains the pre-coded representations of RNA sequences by incorporating the position information into single-nucleotide states with chaos game representation *** then constructs a crossdomain reconstruction encoder to learn the sequential and structural dependencies between *** minimizing the reconstruction and binary cross-entropy losses,CR-NSSD is trained to complete the task of m6A site *** experiments have demonstrated the promising performance of CR-NSSD by comparing it with several state-of-the-art m6A identification ***,the results of cross-species prediction indicate that the integration of sequential and structural dependencies allows CR-NSSD to capture general features of m6A modification sites among different species,thus improving the accuracy of cross-species identification.

关键词： Cross-domain reconstruction cross-species prediction N6-methyladenosine(m6A)modification site RNA sequence sequential and structural dependencies

Linking coral fluorescence phenotypes to thermal bleaching in the reef-building Galaxea fascicularis from the northern South China Sea

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Marine Life Science & Technology 2024年第1期6卷 155-167页

作者： Sanqiang Gong Jiayuan Liang Gang Li Lijia Xu Yehui Tan Xinqing Zheng Xuejie Jin Kefu Yu Xiaomin Xia Key Laboratory of Tropical Marine Bio-Resources and Ecology&Guangdong Provincial Key Laboratory of Applied Marine Biology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 510301China Coral Reef Research Center of China Guangxi UniversityNanning 53004China South China Institute of Environmental Sciences The Ministry of Ecology and Environment of PRCGuangzhou 510530China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China

Coral fluorescence phenotypes have been suggested as an adaptation to a broad range of environmental conditions,yet the mechanisms linking thermal bleaching tolerance in reef-building coral populations,associated with fluorescence phenotypes due to GFP-like proteins,remains *** this study,the relationship between the thermal sensitivity and phenotypic plasticity of corals was investigated using two phenotypes of Galaxea fascicularis,green and *** results reveal that brown *** was more susceptible to bleaching than green *** when exposed to a higher growth temperature of 32℃.Both phenotypes of *** were associated with the thermotolerant Symbiodiniaceae symbiont,Durusdinium ***,the brown *** showed a significant decrease in Symbiodiniaceae cell density and a significant increase in pathogenic bacteria abundance when the growth temperature was raised from 29 to 32℃.The physiological traits and transcriptomic profiles of Symbiodiniaceae were not notably affected,but there were differences in the transcriptional levels of certain genes between the two phenotype hosts of *** heat stress of 32℃,the gene encoding green fluorescent protein(GFP)-like and chromosome-associated proteins,as well as genes related to oxidative phosphorylation,cell growth and death showed lower transcriptional levels in the brown *** compared to the green ***,the results demonstrate that the green form of *** is better able to tolerate ocean warming and defend against pathogenic bacteria,likely due to higher gene transcription levels and defense ability.

关键词： Fluorescence phenotype Thermal bleaching Microbiome Galaxea fascicularis Ocean warming

Lightweight,Strong and High Heat-Resistant Poly(lactide acid)Foams via Microcellular Injection Molding with Self-Assembly Nucleating Agent

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Chinese Journal of Polymer Science 2024年第6期42卷 739-750页

作者： Xiao-Hu Bing Wen-Yu Ma Ming-Hui Wu Peng Gao Xiao Zhou Hai-Bin Luo Long Wang Wen-Ge Zheng School of materials Science and Engineering Shanghai UniversityShanghai200444China Ningbo Key Lab of Polymer Materials Ningbo Institute of Material Technology and EngineeringChinese Academy of SciencesNingbo315201China University of Chinese Academy of Sciences Beijing100049China

Poly(lactide acid)(PLA)foams have shown considerable promise as eco-friendly alternatives to nondegradable plastic foams,such as polystyrene(PS)***,PLA foam typically suffers from low heat-resistance and poor cellular structure stemming from its inherent slow crystallization rate and low melt *** this study,a high-performance PLA foam with well-defined cell morphology,exceptional strength and enhanced heat-resistance was successfully fabricated via a core-back microcellular injection molding(MIM)*** scanning calorimetry(DSC)results revealed that the added hydrazine-based nucleating agent(HNA)significantly increased the crystallization temperature and accelerated the crystallization process of ***,the addition of a 1.5 wt%of HNA led to a significant reduction in PLA’s cell size,from 43.5µm to 2.87µm,and a remarkable increase in cell density,from 1.08×10^(7)cells/cm^(3)to 2.15×10^(10)cells/cm^(3).This enhancement resulted in a final crystallinity of approximately 55.7%for the PLA blend foam,a marked improvement compared to the pure PLA ***,at 1.5 wt%HNA concentration,the tensile strength and tensile toughness of PLA blend foams demonstrated remarkable improvements of 136%and 463%,***,the Vicat softening temperature of PLA blend foam increased significantly to 134.8°C,whereas the pure PLA foam exhibited only about 59.7℃.These findings underscore the potential for the preparation of lightweight injection-molded PLA foam with enhanced toughness and heat-resistance,which offers a viable approach for the production of high-performance PLA foams suitable for large-scale applications.

关键词： Poly(lactide acid) Nucleating agent Microcellular injection molding Heat-resistance Toughness

Experimental determination of the Young’s modulus of individual single-walled carbon nanotubes with single chirality

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Nano Research 2024年第8期17卷 7522-7532页

作者： Jianlin Sun Xiao Zhang Yanchun Wang Mingming Li Xiaojun Wei Huaping Liu Weiya Zhou Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences and College of Materials Science and Optoelectronic Technology University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China Beijing Key Laboratory for Advanced Functional Materials and Structure Research Beijing 100190China

One-dimensional carbon nanotube(CNT)exhibits excellent mechanical properties and is considered to be an ideal candidate material for the space ***,subtle changes in its chirality strongly affect its physical and chemical properties,including mechanical properties(such as Young's modulus,YM).Theoretical studies reveal that the YMs of perfect single-walled carbon nanotubes(SWCNTs)are in the order of TPa and related to their ***,due to the lack of SWCNTs samples with well-defined structures and the difficulties in mechanical tests on individual SWCNTs,the theoretical correlations between YM and structure of SWCNTs have not been verified and are still in debate,which directly influences the practical utilization of the excellent mechanical properties of *** this work,we have developed an experimental method to measure the YM of an individual micrometer-scale suspended CNT by atomic force microscopy.A distinct regularity is found between the YM and chirality(i.e.,chiral angle and diameter)of SWCNT in the experiment for the first *** comparing the YMs of SWCNTs with similar diameters and different chiral angles,it manifests that the SWCNT with a near zigzag configuration has a larger *** finding suggests that the effect of SWCNT’s structures on the YMs cannot be *** developed method of measuring YMs of SWCNTs will be valuable for further experimental research on the inherent physical and chemical properties of SWCNTs.

关键词： Young's modulus single-walled carbon nanotubes single chirality atomic force microscopy

Stereoselective recognition of morphine enantiomers by μ-opioid receptor

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National Science Review 2024年第3期11卷 183-191页

作者： Yibo Wang Van A.Ngo Xiaohui Wang Laboratory of Chemical Biology Changchun Institute of Applied ChemistryChinese Academy of Sciences Advanced Computing for Life Sciences and Engineering Group Science Engagement Section National Center for Computational Sciences Oak Ridge National Lab School of Applied Chemistry and Engineering University of Science and Technology of China Beijing National Laboratory for Molecular Sciences

Stereospecific recognition of chiral molecules plays a crucial role in biological systems. The μ-opioid receptor（MOR） exhibits binding affinity towards（-）-morphine, a well-established gold standard in pain management, while it shows minimal binding affinity for the（+）-morphine enantiomer, resulting in a lack of analgesic activity. Understanding how MOR stereoselectively recognizes morphine enantiomers has remained a puzzle in neuroscience and pharmacology for over half-a-century due to the lack of direct observation techniques. To unravel this mystery, we constructed the binding and unbinding processes of morphine enantiomers with MOR via molecular dynamics simulations to investigate the thermodynamics and kinetics governing MOR's stereoselective recognition of morphine enantiomers. Our findings reveal that the binding of（-）-morphine stabilizes MOR in its activated state, exhibiting a deep energy well and a prolonged residence time. In contrast,（+）-morphine fails to sustain the activation state of ***, the results suggest that specific residues, namely D1142.50and D1473.32, are deprotonated in the active state of MOR bound to（-）-morphine. This work highlights that the selectivity in molecular recognition goes beyond binding affinities, extending into the realm of residence time.

关键词： stereoselective recognition thermodynamics and kinetics residence time morphine enantiomers μ-opioid receptor

Microglia in drug addiction:A perspective from neuroimmunopharmacology

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Zoological Research 2024年第3期45卷 704-706页

作者： Cong Lin Xiaohui Wang Laboratory of Chemical Biology Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchunJilin 130022China Beijing National Laboratory for Molecular Sciences Beijing 100190China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefeiAnhui 230026China

Drug addiction refers to a state of dependence that arises from habitual drug intake and can result in specific withdrawal symptoms upon *** most commonly abused substances include psychostimulants,cannabinoids,and *** drugs are consumed,they stimulate the release of dopamine,a neurotransmitter crucial for the pleasure and reward centers of the *** repeated drug use,the brain undergoes various changes,leading to tolerance,dependence,and addiction(Lüscher et al.,2020).The mechanisms involved in drug addiction are highly complex and involve diverse cell types within the brain.

关键词： addiction drugs intake