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Reflected Beam Displacements of a Slightly Divergent Ultrasonic Gaussian Beam on a Water-Glass Interface Near Rayleigh Angle Incidence

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Chinese Physics Letters 1999年第11期16卷 819-821页

作者： zhu guo-zhen LIU Liang FU De-yong Department of Physics Tsinghua UniversityBeijing 100084

Two reflected beams of a slightly divergent ultrasonic Gaussian beam on a water-glass interface are observed and recorded by a Schlieren system. The lateral displacements of the two reflected beams are measured for incident angle θi in a wide range of 10° around the Rayleigh angle θc. The displacements decrease as the incident angle increases, which is different from the previous predictions for bounded plane-wave beams, where the displacements have extremum at the Rayleigh angle θ*** explanation is based on the fact that the Gaussian beam generated by an ultrasonic transducer with a button (or strip) back electrode is actually slightly divergent. We extend Bertoni and Tamir's theory (Appl. Phys. 2 (1973) 157) to this case, and our calculated curves of the displacements against the incident angle are in agreement with the experimental results for |θi - θc| < 2°.

关键词： slightly incident Gaussian

Deep genome skimming reveals the hybrid origin of Pseudosasa gracilis (Poaceae: Bambusoideae)

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Plant Diversity 2024年第3期46卷 344-352页

作者： Xiang-Zhou Hu Cen guo Sheng-Yuan Qin De-zhu Li zhen-Hua guo Germplasm Bank of Wild Species Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China University of Chinese Academy of Sciences Beijing 100049China

Pseudosasa gracilis(Poaceae:Bambusoideae)is a temperate woody bamboo species endemic to Southcentral China with a narrow *** phylogenetic studies revealed an unexpected,isolated phylogenetic position of *** we conducted phylogenomic analysis by sampling populations of *** and its sympatric species *** and Sinosasa polytricha reflecting different genomic signals,by deep genome *** molecular evidence from chloroplast genes and genome-wide SNPs,we deciphered the phylogenetic relationships of *** plastid and nuclear data indicate that *** is more closely related to Sinosasa,which is discordant with the taxonomic *** further explore this molecular-morphological conflict,we screened 411“perfect-copy”syntenic genes to reconstruct phylogenies using both the concatenation and coalescent *** observed extensive discordance between gene trees and the putative species tree.A significant hybridization event was detected based on 411 genes from the D subgenome,showing *** was a hybrid descendant between Sinosasa longiligulata and ***,with 63.56%and 36.44%inheritance probabilities of each ***,introgression events were detected in the C subgenome between *** and *** in the same distribution *** findings suggest that sympatric hybridization and introgression play a crucial role in the origin of *** providing an empirical example of bamboo of hybrid origin using comprehensive analyses based on genomic data from different inheritance systems and morphological characters,our study represents a step forward in understanding of reticulate evolution of bamboos.

关键词： Phylogenomics Hybridization Introgression Pseudosasa gracilis Pseudosasa Sinosasa

Tenidap is neuroprotective in a pilocarpine rat model of temporal lobe epilepsy

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Chinese Medical Journal 2013年第10期126卷 1900-1905页

作者： TANG Xing-hua WU Xun-yi XU Lan FANG You-xin WANG Jian-hong zhu guo-xing HONG zhen Department of Neurology Huashan Hospital Fudan UniversityShanghai 200040 China

Background Tenidap is a liposoluble non-steroidal anti-inflammatory drug that is easily distributed in the central nervous system and also inhibits the production and activity of cyclooxygenase-2 （COX-2） and cytokines in vitro. This study aimed to evaluate the neuroprotective effect of tenidap in a pilocarpine rat model of temporal lobe epilepsy （TLE）. Methods Tenidap was administered daily at 10 mg/kg for 10 days following pilocarpine-induced status epilepticus （SE） in male Wistar rats after which prolonged generalized seizures resulted in TLE. After tenidap treatment, spontaneous recurrent seizures （SRSs） were recorded by video monitoring （for 7 hours per day for 14 days）. The frequency and severity of the SRSs were observed. Histological and immunocytochemical analyses were used to evaluate the neuroprotective effect of tenidap and detect COX-2 expression, which may be associated with neuronal death. Results There were 46.88±10.70 survival neurons in tenidap-SE group, while there were 27.60±5.18 survival neurons in saline-SE group at -2.4 mm field in the CA3 area. There were 37.75±8.78 survival neurons in tenidap-SE group, while there were 33.40±8.14 survival neurons in saline-SE group at -2.4 mm field in the CA1 area. Tenidap treatment significantly reduced neuronal damage in the CA3 area （P 〈0.05） and slightly reduced damage in the CA1 area. Tenidap markedly inhibited COX-2 expression in the hippocampus, especially in the CA3 area. Conclusion Tenidap conferred neuroprotection to the CA3 area in a pilocarpine-induced rat model of TLE by inhibiting COX-2 expression.

关键词： tenidap cyclooxygenase-2 inhibitors temporal lobe epilepsy

Testing the first law of black hole mechanics with gravitational waves

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 80-86页

作者： Chao-Wan-zhen Wang Jin-Bao zhu guo-Qing Huang Fu-Wen Shu Department of Physics Nanchang University Center for Relativistic Astrophysics and High Energy Physics Nanchang University GCAP-CASPER Physics DepartmentBaylor University

The successful observation of gravitational waves has provided humanity with an additional method to explore the universe, particularly black holes. In this study, we utilize data from LIGO and Virgo gravitational wave observations to test the first law of black hole mechanics, employing two different approaches. We consider the secondary compact object as a perturbation to the primary black hole before the merger, and the remnant black hole as a stationary black hole after the merger. In the pre-merger and post-merger analysis, our results demonstrate consistency with the first law, with an error level of approximate 25% at a68% credibility level for GW190403 051519. In the full inspiral-merger-ringdown analysis, our results show consistency with the first law of black hole mechanics, with an error level of about 6% at a 68% credibility level and 10% at a 95% credibility level for GW191219 163120. Additionally, we observe that the higher the mass ratio of the gravitational wave source, the more consistent our results are with the first law of black hole mechanics. Overall, our study sheds light on the nature of compact binary coalescence and their implications for black hole mechanics.

关键词： gravitational waves black hole mechanics data analysis ringdown

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Oral pyroptosis nanoinhibitor for the treatment of inflammatory bowel disease

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Nano Research 2024年第3期17卷 1748-1759页

作者： zhenxing zhu Dongtao Zhou Yi Yin zhun Li zhen guo Yongchun Pan Yanfeng Gao Jingjing Yang Weiming zhu Yujun Song Yi Li Department of General Surgery Affiliated Jinling HospitalMedical SchoolNanjing UniversityNanjing 210093China College of Engineering and Applied Sciences State Key Laboratory of Analytical Chemistry for Life ScienceNanjing UniversityNanjing 210023China Department of General Surgery Affiliated Drum Tower HospitalMedical SchoolNanjing UniversityNanjing 210008China Department of Biochemistry and Molecular Biology School of Medicine&Holistic Integrative MedicineJiangsu Collaborative Innovation Center of Chinese Medicinal Resources IndustrializationNanjing University of Chinese MedicineNanjing 210023China

Inflammatory bowel disease(IBD)is an autoimmune gastrointestinal disease characterized by chronic relapsing inflammation of the *** pyroptosis that exists in the inflamed intestine can activate damage signals and aggravate local inflammation in ***,we designed an oral pyroptosis nanoinhibitor,DXMS@CuM@PPADT@PSS(DCMP),which can target intestinal lesions,and respond to reactive oxygen species(ROS)to release active sites and drugs at the *** can inhibit the activation of the nucleotide-binding domain and leucine-rich repeat family pyrin domain containing 3(NLRP3)inflammasomes by scavenging ROS,resulting in the down-regulation of gasdermin D(GSDMD)cleavage thus inhibiting *** also improved intestinal barrier function,decreased inflammatory cytokine levels,and increased the diversity of gut microbiota in mice with *** work is believed to expand the biomedical application of nanomaterials for innate immunity modulation.

关键词： inflammatory bowel disease nanoinhibitors pyroptosis synergistic therapy antioxidant

For LEO Satellite Networks: Intelligent Interference Sensing and Signal Reconstruction Based on Blind Separation Technology

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China Communications 2024年第2期21卷 85-95页

作者： Chengjie Li Lidong zhu zhen Zhang The Key Laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and Technology(Southwest Minzu University)Chengdu 610000China National Key Laboratory of Science and Technology on Communications(University of Electronic Science and Technology of China) Chengdu 610000China College of Computer Science(Sichuan University) Chengdu 610000China

In LEO satellite communication networks,the number of satellites has increased sharply, the relative velocity of satellites is very fast, then electronic signal aliasing occurs from time to time. Those aliasing signals make the receiving ability of the signal receiver worse, the signal processing ability weaker,and the anti-interference ability of the communication system lower. Aiming at the above problems, to save communication resources and improve communication efficiency, and considering the irregularity of interference signals, the underdetermined blind separation technology can effectively deal with the problem of interference sensing and signal reconstruction in this scenario. In order to improve the stability of source signal separation and the security of information transmission, a greedy optimization algorithm can be executed. At the same time, to improve network information transmission efficiency and prevent algorithms from getting trapped in local optima, delete low-energy points during each iteration process. Ultimately, simulation experiments validate that the algorithm presented in this paper enhances both the transmission efficiency of the network transmission system and the security of the communication system, achieving the process of interference sensing and signal reconstruction in the LEO satellite communication system.

关键词： blind source separation greedy optimization algorithm interference sensing LEO satellite communication networks signal reconstruction

For Mega-Constellations: Edge Computing and Safety Management Based on Blockchain Technology

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China Communications 2024年第2期21卷 59-73页

作者： zhen Zhang Bing guo Chengjie Li College of Computer Science Sichuan UniversityChengdu 610064China The Key Laboratory for Computer Systems of State Ethnic Affairs Commission School of Computer Science and TechnologySouthwest Minzu UniversityChengdu 610225China National Key Laboratory of Science and Technology on Communications University of Electronic Science and Technology of ChinaChengdu 611731China

In mega-constellation Communication Systems, efficient routing algorithms and data transmission technologies are employed to ensure fast and reliable data transfer. However, the limited computational resources of satellites necessitate the use of edge computing to enhance secure *** edge computing reduces the burden on cloud computing, it introduces security and reliability challenges in open satellite communication channels. To address these challenges, we propose a blockchain architecture specifically designed for edge computing in mega-constellation communication systems. This architecture narrows down the consensus scope of the blockchain to meet the requirements of edge computing while ensuring comprehensive log storage across the network. Additionally, we introduce a reputation management mechanism for nodes within the blockchain, evaluating their trustworthiness, workload, and efficiency. Nodes with higher reputation scores are selected to participate in tasks and are appropriately incentivized. Simulation results demonstrate that our approach achieves a task result reliability of 95% while improving computational speed.

关键词： blockchain consensus mechanism edge computing mega-constellation reputation management

High-Performance Recyclable Furan-based Epoxy Resin and Its Carbon Fiber Composites with Dense Hydrogen Bonding

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Chinese Journal of Polymer Science 2024年第1期42卷 73-86,I0008页

作者： Chang-Bo Zhao Lu-Kun Feng Hui Xie Ming-Liang Wang Bing guo Zhi-Yong Xue Cai-zhen zhu Jian Xu Advanced Materials Research Institute North China Electric Power UniversityBejing 102206China Institute of Low-Dimensional Materials Genome Initiative College of Chemistry and Environmental EngineeringShenzhen UniversityShenzhen 518060China Chengdu Institute of Organic Chemistry Chinese Academy of SciencesChengdu 610041China School of Science and Shenzhen Key Laboratory of Flexible Printed Electronics Technology and Shenzhen Key Laboratory of Advanced Functional Carbon Materials Research and Comprehensive ApplicationHarbin Institute of TechnologyShenzhen 518055China

The emerging biomass-based epoxy vitrimers hold great potential to fulfill the requirements for sustainable development of *** the existence of dynamic chemical bonds in vitrimers often reduces both the thermal and mechanical properties of epoxy resins, it is challenging to produce recyclable epoxy vitrimers with both excellent mechanical properties and good thermal stability. Herein, a monomer 4-(((5-(hydroxymethyl)furan-2-yl)methylene)amino)phenol(FCN) containing furan ring with potential to form high density of hydrogen bonding among repeating units is designed and copolymerized with glycerol triglycidyl ether to yield epoxy resin(FCN-GTE), which intrinsically has dual hydrogen bond networks, dynamic imine structure and resultant high performance. Importantly, as compared to the BPA-GTE, the FCN-GTE exhibits significantly improved mechanical properties owing to the increased density of hydrogen bond network and physical crosslinking interaction. Furthermore, density functional theory(DFT) calculation and in situ FTIR analysis is conducted to decipher the formation mechanism of hydrogen bond network. In addition, the FCN-GTE possesses superior UV shielding, chemical degradation, and recyclability because of the existence of abundant imine bonds. Notably, the FCN-GTE-based carbon fiber composites could be completely recycled in an amine *** study provides a facile strategy for synthesizing recyclable biomass-based high-performance epoxy vitrimers and carbon fiber composites.

关键词： Furan Hydrogen bond network Dynamic Schiff base Carbon fiber composites Recycling

A General Simulation Method for Complex Deformation of Irregular-Shaped Origami Configurations

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Acta Mechanica Solida Sinica 2024年第1期37卷 90-98页

作者： Zhaochen Dong Yichao zhu Xu guo State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsInternational Research Center for Computational MechanicsDalian University of TechnologyDalian 116023China

Most existing treatments for origami-folding simulations have focused on regular-shaped *** article aims to introduce a general strategy for simulating and analyzing the deformation process of irregular shapes by means of computational capabilities *** better simulate origami deformation with folding orders,the concept of plane follow-up is introduced to achieve automated computer simulation of complex folding patterns,thereby avoiding intersection and penetration between *** on the evaluation criteria such as the lowest storage energy with tightening and the fastest pace from tightening to unfolding,the optimal crease distribution patterns for four irregular(‘N’-,‘T’-,‘O’-,and‘P’-shaped)origami configurations are then presented under five *** the dimensions of the origami are fixed,it is discovered that simpler folding patterns lead to faster deformation of the origami *** the folding complexity is fixed,higher strain energy results in more rapid origami expansion.

关键词： Irregular-shaped origami Complex deformation Computer-aided origami design General simulation