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*-Regular Leavitt Path Algebras of Arbitrary graphs

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Acta Mathematica Sinica,english Series 2012年第5期28卷 957-968页

作者： gonzalo ARANDA PINO Kulumani RANgASWAMY lia VA Departamento de lgebra Geometría y Topología Universidad de Mlaga Department of Mathematics University of Colorado Department of Mathematics Physics and Statistics University of the Sciences in Philadelphia

If K is a field with involution and e an arbitrary graph, the involution from K naturally induces an involution of the Leavitt path algebra LK（e）. We show that the involution on LK（e） is proper if the involution on K is positive-definite, even in the case when the graph e is not necessarily finite or row-finite. It has been shown that the Leavitt path algebra LK（e） is regular if and only if e is acyclic. We give necessary and sufficient conditions for LK（e） to be ＊-regular （i.e., regular with proper involution）. This characterization of ＊-regularity of a Leavitt path algebra is given in terms of an algebraic property of K, not just a graph-theoretic property of e. This differs from the known characterizations of various other algebraic properties of a Leavitt path algebra in terms of graph- theoretic properties of e alone. As a corollary, we show that Handelman＇s conjecture （stating that every ,-regular ring is unit-regular） holds for Leavitt path algebras. Moreover, its generalized version for rings with local units also continues to hold for Leavitt path algebras over arbitrary graphs.

关键词： Leavitt path algebra *-regular involution arbitrary graph

基于三轴不排水有效应力路径的结构性剑桥模型的修正研究

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岩土工程学报 2025年第1期47卷 115-124页

作者：加瑞李逸群雷华阳姜宇轩天津大学建筑工程学院天津300350 天津大学滨海土木工程结构与安全教育部重点实验室天津300350

室内外试验和工程实践都表明天然沉积黏土具有一定的结构性,因此建立结构性本构模型对准确预测天然黏土的力学响应和解决实际岩土工程问题具有重要意义。首先,基于结构性黏土的三轴固结不排水试验的有效应力路径对结构性剑桥(SCC)模型... 详细信息

室内外试验和工程实践都表明天然沉积黏土具有一定的结构性,因此建立结构性本构模型对准确预测天然黏土的力学响应和解决实际岩土工程问题具有重要意义。首先,基于结构性黏土的三轴固结不排水试验的有效应力路径对结构性剑桥(SCC)模型进行了两点改进:(1)对附加孔隙比Δe的计算公式进行了修正,可以准确模拟结构性黏土超过临界状态线后的有效应力路径;(2)考虑了屈服面内的塑性即亚屈服特性,可以较好地模拟屈服面内的有效应力路径然后,利用修正结构性剑桥(MSCC)模型对结构性黏土的侧限压缩试验、三轴固结不排水和三轴固结排水试验进行了模拟计算,并与试验结果和SCC模型的计算结果进行了对比分析,结果表明MSCC模型可以更好地模拟结构性黏土的三轴不排水有效应力路径以及侧限压缩和三轴固结排水试验的应力应变曲线。最后,对MSCC模型中的参数β(屈服面内塑性变形参数)、p'_(yi)(初始结构屈服应力)、Δe_i(初始附加孔隙比)、b(结构破损速率)、γ(剪切引起结构破损的参数)和ω(反映结构性对塑性流动准则的影响)进行了参数敏感性分析,结果表明参数β影响结构性黏土屈服面内的有效应力路径,参数p'_(yi)影响峰值强度,参数Δe_i影响残余强度,参数b和γ影响峰值后的强度衰减速率,参数ω影响强度开始衰减时的偏应变大小。

关键词：结构性黏土结构性剑桥模型有效应力路径亚屈服附加孔隙比

Axonal growth inhibitors and their receptors in spinal cord injury:from biology to clinical translation

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Neural Regeneration Research 2023年第12期18卷 2573-2581页

作者： Sílvia Sousa Chambel Célia Duarte Cruz experimental Biology Unit Department of BiomedicineFaculty of Medicine of PortoUniversity of PortoPortoPortugal Translational NeuroUrology Instituto de Investigação e Inovação em Saúde-i3S and IBMCUniversidade do PortoPortoPortugal

Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibitory environment for axonal regeneration. Among these inhibitory molecules, myelinassociated inhibitors, including neurite outgrowth inhibitor A, oligodendrocyte myelin glycoprotein, myelin-associated glycoprotein, chondroitin sulfate proteoglycans and repulsive guidance molecule A are of particular importance. Due to their inhibitory nature, they represent exciting molecular targets to study axonal inhibition and regeneration after central injuries. These molecules are mainly produced by neurons, oligodendrocytes, and astrocytes within the scar and in its immediate vicinity. They exert their effects by binding to specific receptors, localized in the membranes of neurons. Receptors for these inhibitory cues include Nogo receptor 1, leucine-rich repeat, and Ig domain containing 1 and p75 neurotrophin receptor/tumor necrosis factor receptor superfamily member 19(that form a receptor complex that binds all myelin-associated inhibitors), and also paired immunoglobulin-like receptor B. Chondroitin sulfate proteoglycans and repulsive guidance molecule A bind to Nogo receptor 1, Nogo receptor 3, receptor protein tyrosine phosphatase σ and leucocyte common antigen related phosphatase, and neogenin, respectively. Once activated, these receptors initiate downstream signaling pathways, the most common amongst them being the Rho A/ROCK signaling pathway. These signaling cascades result in actin depolymerization, neurite outgrowth inhibition, and failure to regenerate after spinal cord injury. Currently, there are no approved pharmacological treatments to overcome spinal cord injuries other than physical rehabilitation and management of the array of symptoms brought on by spinal cord injuries. However, several novel therapies aiming to modulate these inhibitory prot

关键词： chondroitin sulphate proteoglycans collapsin response mediator protein 2 inhibitory molecules leucine-rich repeat and Ig domain containing 1 leucocyte common antigen related myelin-associated glycoprotein neurite outgrowth inhibitor A Nogo receptor 1 Nogo receptor 3 oligodendrocyte myelin glycoprotein p75 neurotrophin receptor Plexin A2 Ras homolog family member A/Rho-associated protein kinase receptor protein tyrosine phosphataseσ repulsive guidance molecule A spinal cord injury tumour necrosis factor receptor superfamily member 19

Hard carbon derived from coconut shells,walnut shells,and corn silk biomass waste exhibiting high capacity for Na-ion batteries

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Journal of energy Chemistry 2021年第7期30卷 207-218页

作者： Cristina Nita Biao Zhang Joseph Dentzer Camélia Matei ghimbeu Universitéde Haute-Alsace Institut de Science des Matériaux de Mulhouse(IS2M)CNRS UMR 7361F-68100 MulhouseFrance Universitéde Strasbourg F-67081 StrasbourgFrance Center for Advanced Laser Technologies(CeTAL) National Institute for LasersPlasma and Radiation PhysicsAtomistilor 409 bisRO-77125 MagureleRomania Department of Applied Physics The Hong Kong Polytechnic UniversityKowloonHong KongChina Réseau sur le Stockage electrochimique de l’energie(RS2e) CNRS FR345933 Rue Saint Leu80039 Amiens CedexFrance

In recent years,hard carbon materials have gained significant interest as anode materials for Na-ion *** waste is considered one of the most interesting,renewable,available,and cost-effective precursor to obtain hard carbon(HC);however,HC properties must be finely tuned to achieve performance comparable to those provided by Li-ion *** this work,three biomass wastes(coconut shells,walnut shells,and corn silk) were evaluated as potential precursors for HC preparation involving a pyrolysis process and subsequent acid washing to remove the inorganic *** obtained materials exhibited low and similar specific surface areas(g^(-1)), but they presented different structures and surface *** walnut shell HC possessed a lower amount of inorganic impurities and oxygen-based functional groups compared to the coconut shell and corn silk HCs,leading to higher initial coulombic efficiency(iCe).The structural organization was higher in the case of the walnut shell HC,while the corn silk HC revealed a heterogeneous structure combining both highly disordered carbon and localized graphitized *** HCs delivered high initial reversible capacities between 293 and 315 mAh g^(-1) at 50 mA g^(-1) current rate,which remained rather stable during long-term *** best capacity(293 mAh g^(-1) after 100 charge/discharge cycles) and highest capacity retention(93%) was achieved in walnut HCs in half-cells,which could be associated with its higher sp2 C content,better organized structure,and fewer *** "adsorption-insertion" Na storage mechanism is suggested based on several *** walnut HCs exhibited an attractive energy density of 279 Wh/kg when tested in full cells.

关键词： Biomass Pyrolysis Hard carbon Anode Na-ion batteries energy storage

Renin angiotensin system in liver diseases: Friend or foe?

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World Journal of gastroenterology 2017年第19期23卷 3396-3406页

作者： Ana Cristina Simoes e Silva Aline S Miranda Natália P Rocha Antonio L Teixeira Department of Pediatrics Faculty of MedicineFederal University of Minas Gerais Interdisciplinary Laboratory of Medical Investigation Faculty of MedicineUFMG Laboratory of Neurobiology Department of MorphologyInstitute of Biological SciencesUFMG Neuropsychiatry Program Department of Psychiatry and Behavioral SciencesMcGovern Medical SchoolUniversity of Texas Health Science Center at Houston

In the last three decades,the understanding of the renin angiotensin system(RAS)has been changed by the discoveries of functional local systems,novel biologically active peptides,additional specific receptors,alternative pathways of angiotensin(Ang)?Ⅱ?generation,and new roles for enzymes and precursor components other than those in Ang?Ⅱ?*** this regard,the discovery that Ang-(1-7)opposes the pressor,proliferative,pro-fibrotic,and pro-inflammatory effects mediated by Ang?Ⅱ?has contributed to the realization that the RAS is composed of two *** first axis consists of the angiotensin-converting enzyme(ACe),with Ang?Ⅱ?as the end product,and the angiotensin type 1(AT1)receptor as the main effector mediating the biological actions of Ang?Ⅱ.The second axis results from ACe2-mediated hydrolysis of Ang?Ⅱ,leading to the production of Ang-(1-7),with the Mas receptor as the main effector conveying the vasodilatory,antiproliferative,anti-fibrotic,and anti-inflammatory effects of Ang-(1-7).experimental and clinical studies have shown that both axes of the RAS may take part in the pathogenesis of liver *** this manuscript,we summarize the current evidence regarding the role of RAS in hepatic cirrhosis and its complications,including hemodynamic changes and hepatorenal *** therapeutic potential of the modulation of RAS molecules in liver diseases is also discussed.

关键词： Renin angiotensin system Angiotensin Ⅱ Angiotensin-(1-7) Hepatic cirrhosis Liver fibrosis Hepatorenal syndrome

Particle Simulation of the Fast Ignition Mechanism for Laser Fusion

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Chinese Physics Letters 2001年第6期18卷 799-801页

作者： ZHANg jia-Tai He Bin N.e.Andreev Institute of Applied Physics and Computational Mathematics P.O.Box 8009Beijing 100088 Joint Institute for High Temperature Russian Academy of SciencesMoscow 127412Russia

We have developed the two and half-dimension electromagnetic relativistic electron and mobile ion cloud-in-cell(CIC)*** of the fast ignition and interaction of ultra-intense and ultra-short pulse laser with plasma are analysed theoretically and simulated numerically using CIC *** flows of relativistic electron and form of the channel are *** results show that the temperature of superhot electron is about MeV to tens of MeV,and the boring velocity is 0.05c-0.1c with c being the light *** preliminary scale laws are *** simulation quantitatively reproduces the experimental results at early and long times.

关键词： relativistic intense dimension

An experimental Investigation on Heat Transfer Performance of Nanofluid Pulsating Heat Pipe

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Journal of Thermal Science 2013年第5期22卷 484-490页

作者： Hongwei jia Li jia Zetao Tan Institute of Thermal energy engineering School of Mechanical Electronic and Control EngineeringBeijing Jiaotong University jiangsu Key Laboratory of Process enhancement & New energy equipment Technology Nanjing University of Technology

The effect of SiO2 particles on heat transfer performance of a pulsating heat pipe （PHP） was investigated experi- mentally. DI water was used as the base fluid and contrast medium for the PHP. In order to study and measure the character, there are SiO2/H20 nanofluids with different concentration and applying with various heating powers during the experiment investigation. According to the experimental result, the high fraction of SiO2/H20 will de- teriorate the performance of PHP compared with DI water, i.e. the thermal resistance and the temperature of evaporation section increases. It is in contrary in the case of low fraction of SiO2/H20. Finally, the comparison of the thermal performances between the normal operation system and the static settlement system is given. It is found that both the thermal resistance of nanofluid PHP and the temperature of the evaporation section increase after standing for a period, and it is the same trend for the temperature fluctuation at the identical heating power for PHP.

关键词： Nanofluid Pulsating heat pipe Heat transfer characteristics Suspension characteristics

Research on Optimum Operation and Structure of Tundish

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Journal of Iron and Steel Research International 2002年第1期9卷 25-27页

作者： ZHANg Quan ZHANg Ming e jia-qiang ZHOU Ying-qi Central South University Xiangtan Iron and Steel Co Ltd

With the technical progress of metallurgical industry, more excess gas will be produced in steel works. The feasibility of producing dimethyl ether by gas synthesis was discussed, which focused on marketing, energy balance, process design, economic evaluation, and environmental protection etc. DMe was considered to be a new way to utilize excess coal gas in steel works.

关键词： steel works excess coal gas dimethyl ether chemical technology

electricity-Heat-Based Integrated Demand Response Considering Double Auction energy Market with Multi-energy Storage for Interconnected Areas

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CSee Journal of Power and energy Systems 2024年第4期10卷 1688-1700页

作者： Dan Wang Deyu Huang Qing'e Hu Hongjie jia Bo Liu Yang Lei Key Laboratory of Smart grid of Ministry of education Tianjin UniversityTianjin 300072China Key Laboratory of Smart energy&Information Technology of Tianjin Municipality Tianjin 30072China

With development of integrated energy systems and energy markets,transactive energy has received increasing attention from society and academia,and realization of energy distribution and integrated demand response through market transactions has become a current research *** on optimized operation of a distributed energy station as a regional energy supply center is of great significance for improving flexibility and reliability of the *** on retail-side energy trading market,this study first establishes a framework of combined electric and heating energy markets and analyses a double auction market mechanism model of interconnected distributed energy *** study establishes a mechanism model of energy market participants,and establishes the electric heating combined market-clearing model to maximize global surplus considering multi-energy ***,in the case study,a typical user energy consumption scenario in winter is selected,showing market-clearing results and demand response effects on a typical *** of transmission line constraints,energy supply equipment capacity,and other factors on clearing results and global surplus are compared and analyzed,verifying the effects of the proposed method on improving global surplus,enhancing interests of market participants and realizing coordination and optimal allocation of both supply and demand resources through energy complementarity between regions.

关键词： Double auction energy market integrated energy system interconnected energy stations multi-energy storage