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Regenerative peripheral nerve interface prevents neuroma formation after peripheral nerve transection

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Neural Regeneration Research 2023年第4期18卷 814-818页

作者： Zheng Wang Xin-Zeyu Yi ai-Xi Yu Department of Orthopedics Trauma and Microsurgery Zhongnan Hospital of Wuhan UniversityWuhanHubei ProvinceChina

Neuroma formation after peripheral nerve transection often leads to severe neuropathic *** peripheral nerve interface has been shown to reduce painful neuroma in the ***,no reports have investigated the underlying mechanisms,and no comparative animal studies on regenerative peripheral nerve interface and other means of neuroma prevention have been conducted to *** this study,we established a rat model of left sciatic nerve transfection,and subsequently interfered with the model using the regenerative peripheral nerve interface or proximal nerve stump implantation inside a fully innervated *** showed that,compared with rats subjected to nerve stump implantation inside the muscle,rats subjected to regenerative peripheral nerve interface intervention showed greater inhibition of the proliferation of collagenous fibers and irregular regenerated axons,lower expressions of the fibrosis markerα-smooth muscle actin and the inflammatory marker sigma-1 receptor in the proximal nerve stump,lower autophagy behaviors,lower expressions of c-fos and substance P,higher expression of glial cell line-derived neurotrophic factor in the ipsilateral dorsal root *** findings suggested that regenerative peripheral nerve interface inhibits peripheral nerve injury-induced neuroma formation and neuropathic pain possibly via the upregulation of the expression of glial cell line-derived neurotrophic factor in the dorsal root ganglia and reducing neuroinflammation in the nerve stump.

关键词： autotomy dorsal root ganglia glial cell line-derived neurotrophic factor nerve injury neuropathic pain peripheral nerve regeneration regenerative peripheral nerve interface retrograde axonal transport traumatic neuroma

Effect of cr content on the compression Properties and Abrasive Wear Behavior of the High-Volume Fraction(Tic–TiB_2)/cu composites

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Acta Metallurgica Sinica(English Letters) 2014年第5期27卷 951-956页

作者： Feng Qiu Yue Han ai cheng Jianbang Lu Qichuan Jiang Key Laboratory of Automobile Materials Ministry of EducationDepartment of Materials Science and EngineeringJilin University

The （Tic-TiB2）/cu composites with 50 vol% Tic-TiB2 ceramic particles were successfully fabricated by the combustion synthesis and hot press consolidation in a cu-Ti-B4c-cr system. The effects of the cr content on the microstructures, hardness, compression properties, and abrasive wear behaviors of the composites were investigated. The final products consist of only cu, Tic, and TiB2 phases, and the ceramic particles are distributed uniformly in these composites. The size of the ceramic particles decreases with cr addition. As the cr content increases, the yield strength, ultimate compression strength, microhardness, and abrasive wear resistance of the composites increase, and the fracture strain decreases.

关键词： Metal matrix composites Powder metallurgy combustion synthesis Abrasive wear

Lock threshold deterioration induced by antenna vibration and signal coupling effects in hypersonic vehicle carrier tracking system of Ka band

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chinese Journal of Aeronautics 2018年第4期31卷 776-781页

作者： congying ZHU Lei SHI Xiaoping LI Yanming LIU Wei ai School of Aerospace Science and Technology Xidian University

The envelope of a hypersonic vehicle is affected by severe fluctuating pressure, which causes the airborne antenna to vibrate slightly. This vibration mixes with the transmitted signals and thus introduces additional multiplicative phase noise. Antenna vibration and signal coupling effects as well as their influence on the lock threshold of the hypersonic vehicle carrier tracking system of the Ka band are investigated in this study. A vibration model is initially established to obtain phase noise in consideration of the inherent relationship between vibration displacement and electromagnetic wavelength. An analytical model of the Phase-Locked Loop（PLL）, which is widely used in carrier tracking systems, is established. The coupling effects on carrier tracking performance are investigated and quantitatively analyzed by imposing the multiplicative phase noise on the PLL model. Simulation results show that the phase noise presents a Gaussian distribution and is similar to vibration displacement variation. A large standard deviation in vibration displacement exerts a significant effect on the lock threshold. A critical standard deviation is observed in the PLL of Binary Phase Shift Keying（BPSK） and Quadrature Phase Shift Keying（QPSK） signals. The effect on QPSK signals is more severe than that on BPSK signals. The maximum tolerable standard deviations normalized by the wavelength of the carrier are 0.04 and 0.02 for BPSK and QPSK signals,respectively. With these critical standard deviations, lock thresholds are increased from à12 andà4 d B to 3 and à2 d B, respectively.

关键词： Antenna vibration carrier tracking performance Lock threshold Phase locked loop Tracking Telemetry and command(TT&c) signals

Nonreciprocal transition between two indirectly coupled energy levels

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Frontiers of physics 2022年第4期17卷 153-161页

作者： Xun-Wei Xu Hai-Quan Shi ai-Xi chen Key Laboratory of Low-Dimensional Quantum Structures and Quantum control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan ProvinceDepartment of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China Department of Applied Physics East China Jiaotong UniversityNanchang 330013China Department of Physics Zhejiang Sci-Tech UniversityHangzhou 310018China

We propose a theoretical scheme to realize nonreciprocal transition between two energy levels that can not coupled *** they are coupled indirectly by two auxiliary levels with a cyclic four-level configuration,and the four transitions in the cyclic configuration are controlled by external *** indirectly transition become nonreciprocal when the time reversal symmetry of the system is broken by the synthetic magnetic flux,i.e.,the total phase of the external driving fields through the cyclic four-level *** nonreciprocal transition can be identified by the elimination of a spectral line in the spontaneous emission *** work introduces a feasible way to observe nonreciprocal transition in a wide range of multi-level systems,including natural atoms or ions with parity symmetry.

关键词： nonreciprocal transition time reversal symmetry synthetic magnetic flux spontaneous emission spectrum

ExtSpecR:An R Package and Tool for Extracting Tree Spectra from UAV-Based Remote Sensing

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Plant Phenomics 2023年第4期5卷 893-904页

作者： Zhuo Liu Mahmoud ai-Sarayreh cong Xu Federico Tomasetto Yanjie Li State Key Laboratory of Tree Genetics and Breeding Research Institute of Subtropical ForestryChinese Academy of ForestryHangzhouZhejiang 311400China Key Laboratory of Tree Breeding of Zhejiang Province Research Institute of Subtropical ForestryChinese Academy of ForestryHangzhouZhejiang 311400China Department of computer Engineering German Jordanian UniversityAmman 11180Jordan School of Forestry University of CanterburyPrivate Bag 4800Christchurch 8140New Zealand AgResearch Ltd. Christchurch 8140New Zealand

The development of unmanned aerial vehicle(UAV)remote sensing has been increasingly applied in forestry for high-throughput and rapid acquisition of tree phenomics traits for various research ***,the detection of individual trees and the extraction of their spectral data remain a challenge,often requiring manual *** several software-based solutions have been developed,they are far from being widely *** paper presents ExtSpecR,an open-source tool for spectral extraction of a single tree in forestry with an easy-to-use interactive web *** reduces the time required for single tree detection and annotation and simplifies the entire process of spectral and spatial feature extraction from UAV-based *** addition,ExtSpecR provides several functionalities with interactive dashboards that allow users to maximize the quality of information extracted from UAV *** can promote the practical use of UAV remote sensing data among forest ecology and tree breeding researchers and help them to further understand the relationships between tree growth and its physiological traits.

关键词： interactive Remote Tool

Serological surveillance for SARS-coV-2 antibodies among students,faculty and staff within a large university system during the pandemic

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World Journal of Virology 2025年第1期14卷 99-107页

作者： Marcos G Pinheiro Gabriela G O Alves Maria Eduarda R conde Sofia L costa Regina c S Sant’Anna Isa M F Antunes Mônica c carneiro Fabio S Ronzei Julia c Scaffo Felipe R Pinheiro Lialyz S Andre Helvecio c Povoa Valéria T Baltar Fabíola Giordani Eduarda S Hemerly Gisele c Alexandre Karla c de Paula Márcio Watanabe Antonio claudio L da Nóbrega Jackeline christiane P Lobato Fabio Aguiar-Alves Laboratory of Molecular Epidemiology and Biotechnology Rodolpho Albino University LaboratoryFluminense Federal UniversityNiterói 24241000Rio de JaneiroBrazil Estácio de SáUniversity Nova Friburgo 28611135Rio de JaneiroBrazil Pathology Program Medicine schoolFluminense Federal UniversityNiterói 24070090Rio de JaneiroBrazil Department of Pharmaceutical Sciences Lloyd L.Gregory School of PharmacyPalm Beach Atlantic UniversityWest Palm BeachFL 33401United States Health Institute of Nova Friburgo Fluminense Federal UniversityNova Friburgo 28613001Rio de JaneiroBrazil Department of Epidemiology and Biostatistics Institute of Collective Health(ISC)Fluminense Federal UniversityNiterói 24033900Rio de JaneiroBrazil Institute of Physical Education Fluminense Federal UniversityNiterói 24020005Rio de JaneiroBrazil Department of Statistics Fluminense Federal UniversityNiterói 24210200Rio de JaneiroBrazil Department of Physiology and Pharmacology Fluminense Federal UniversityNiterói 24210130Rio de JaneiroBrazil

BAcKGROUND At the end of December 2019,the world faced severe acute respiratory syndrome-coronavirus 2(SARS-coV-2),which led to the outbreak of coronavirus disease 2019(cOVID-19),associated with respiratory *** virus has shown significant challenges,especially for senior citizens,patients with other underlying illnesses,or those with a sedentary *** tests conducted early on have helped identify how the virus is transmitted and how to curb its *** study hypothesis was that the rapid serological test for SARS-coV-2 antibodies could indicate the immunoreactive profile during the cOVID-19 pandemic in a university *** To conduct active surveillance for serological expression of anti-SARS-coV-2 antibodies in individuals within a university setting during the cOVID-19 *** This sectional study by convenience sampling was conducted in a large university in Niteroi-RJ,Brazil,from March 2021 to July *** study population consisted of students,faculty,and administrative staff employed by the university.A total of 3433 faculty members,60703 students,and 3812 administrative staff were invited to *** were gathered through rapid serological tests to detect immunoglobulin(Ig)M and IgG against ***χ²or Fisher's exact test was used to conduct statistical analysis.A 0.20 significance level was adopted for variable selection in a multiple logistic regression model to evaluate *** A total of 1648 individuals were enrolled in the *** proportion of cOVID-19 positivity was 164/1648(9.8%).The adjusted logistic model indicate a positive association between the expression of IgM or IgG and age[odds ratio(OR)=1.16,95%cI:1.02-1.31](Pcontact with a cOVID-19-positive case(OR=3.49,95%cI:2.34-5.37)(Pceived the cOVID-19 vaccine(OR=2.33,95%cI:1.61-3.35)(Pcial isolation(OR=0.59,95%cI:0.41-0.84)(P<0.004).The likelihood of sho

关键词： Serological surveillance SARS-coV-2 antibodies cOVID-19 Serological rapid test Risk factors for cOVID-19

Early-age strength property improvement and stability analysis of unclassified tailing paste backfill materials

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International Journal of Minerals,Metallurgy and Materials 2020年第9期27卷 1191-1202页

作者： Qian Zhou Juan-hong Liu ai-xiang Wu Hong-jiang Wang School of civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of High-Efficient Mining and Safety of Metal Ministry of EducationUniversity of Science and Technology BeijingBeijing 100083China

High-density tailings,small cementitious materials,and additives are used for backfill materials with poor early compressive strength(EcS),which may greatly affect the mining and backfill cycle,to prepare paste backfill materials(PBMs)with a high *** effects and mechanisms of different early strength agents on the property of PBM are *** action mechanism of additives on the properties of PBM is also analyzed through X-ray diffraction,scanning electron microscope,and energy dispersive *** show that the effects of single-component additives 1,3,and 6 are better than those of the other additives,and their optimal dosages are 3wt%,1wt%,and 3wt%,*** optimum multicomponent combinations are 1wt%of additive 1 and 1.5wt%of additive *** EcS of the paste with additive 10 increases to a greater extent than that of the other pastes because of the synergistic action of additive 1 with additive *** hydration product of ca(OH)2 is consumed,and more c-S-H gels are generated with the addition of additives to *** particles,ettringite crystals,and gels intertwined with one another form a dense net-like structure that fills the *** structure can significantly improve the EcS of PBM.

关键词： paste backfill unclassified tailings binder powder early-age strength microstructure

Review on the Progress and Issues in Liquid Tank Sloshing of Ships

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china Ocean Engineering 2023年第5期37卷 709-724页

作者： ZHANG Zhen TAO ai-feng WU Qiao-rui XIE Yong-he Key Laboratory of Ministry of Education for coastal Disaster and Protection Hohai UniversityNanjing 210098China college of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China college of Naval Architecture and Maritime Zhejiang Ocean UniversityZhoushan 316022China

With the development of large liquid cargo ships,liquid tank sloshing has gradually become a hot research topic in the area of shipping and ocean *** tank sloshing,characterized by strong nonlinearity and randomness,not only affects the stability of the ship but also generates a huge impact force on the wall of the *** further investigate liquid tank sloshing,a comprehensive review is given on the research process of the most focused subjects of liquid *** the existing research will help to identify issues in the current field and provide useful *** methods for investigating sloshing,the research progress and the situations worldwide are *** advantages and defects of experiments and numerical simulations are also *** problems which need to be explored in the future are subsequently proposed.

关键词： naval architecture and marine engineering liquid tank sloshing liquid cargo ship large deformation progress review

constructing refined null models for statistical analysis of signed networks

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chinese Physics B 2021年第3期30卷 571-577页

作者： ai-Wen Li Jing Xiao Xiao-Ke Xu college of Information and communication Engineering Dalian Minzu UniversityDalian 116600China

The establishment of effective null models can provide reference networks to accurately describe statistical properties of real-life signed *** present,two classical null models of signed networks(i.e.,sign and full-edge randomized models)shuffle both positive and negative topologies at the same time,so it is difficult to distinguish the effect on network topology of positive edges,negative edges,and the correlation between *** this study,we construct three re-fined edge-randomized null models by only randomizing link relationships without changing positive and negative degree *** results of nontrivial statistical indicators of signed networks,such as average degree connectivity and clustering coefficient,show that the position of positive edges has a stronger effect on positive-edge topology,while the signs of negative edges have a greater influence on negative-edge *** some specific statistics(e.g.,embeddedness),the results indicate that the proposed null models can more accurately describe real-life networks compared with the two existing ones,which can be selected to facilitate a better understanding of complex structures,functions,and dynamical behaviors on signed networks.

关键词： signed networks null models statistical analysis average degree connectivity embeddedness