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The Ext-Group of Unitary Equivalence Classes of Unital Extensions

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Acta Mathematica Sinica,English Series 2011年第12期27卷 2329-2342页

作者： yi feng XUE Department of Mathematics East China Normal University Shanghai 200241 P. R. China

Let A be a unital separable nuclear C＊-algebra which belongs to the bootstrap category N and B be a separable stable C＊-algebra. In this paper, we consider the group Ext,（A, B） consisting of the unitary equivalence classes of unital extensions T： A→ Q（B）. The relation between Ext,（A, B） and Ext（A, B） is established. Using this relation, we show the half-exactness of Ext,（-, B） and the （UCT） for Ext,（A, B）. Furthermore, under certain conditions, we obtain the half-exactness and Bott periodicity of Extu （A, .）.

关键词： Unital extension multiplier algebra Ext-group quasi-unital ,-homomorphism

植物源外泌体样纳米囊泡刺激成骨细胞、抑制破骨细胞并促进成骨

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中国组织工程研究 2025年第31期29卷 6765-6771页

作者：药文鑫王毅蔡林冯晓波武汉大学中南医院疼痛科湖北省武汉市430071 武汉大学中南医院脊柱与骨肿瘤科湖北省武汉市430071

背景:骨质疏松症易引发病理性骨折且严重影响患者的生活质量,植物源外泌体样纳米囊泡在调节骨质疏松症骨平衡方面发挥着重要作用。目的:综述不同植物源外泌体样纳米囊泡在骨质疏松症治疗中的研究现状与展望。方法:通过计算机在PubMed、W... 详细信息

背景:骨质疏松症易引发病理性骨折且严重影响患者的生活质量,植物源外泌体样纳米囊泡在调节骨质疏松症骨平衡方面发挥着重要作用。目的:综述不同植物源外泌体样纳米囊泡在骨质疏松症治疗中的研究现状与展望。方法:通过计算机在PubMed、Web of Science、中国知网中检索1995年1月至2024年3月发表的相关文献,以“osteoporosis,plant-derived exosome-like nanovesicles,exosomes,osteoblasts,osteoclasts”为英文检索词,以“骨质疏松症,植物源外泌体样纳米囊泡,外泌体,成骨细胞,破骨细胞”为中文检索词,最终纳入53篇文献进行分析。结果与结论:植物源外泌体样纳米囊泡具有生物相容性、低毒性和天然靶向性等优点,这些特性不仅确保了其在体内的稳定存在与有效作用,还避免了不必要的免疫反应,为长期治疗策略的设计奠定了基础。植物源外泌体样纳米囊泡可以通过刺激成骨细胞增殖、抑制破骨细胞分化以及促进成骨-抑制破骨双重作用抗骨质疏松症;此外,部分植物源外泌体样纳米囊泡因具有骨靶向性,未来或将成为新型示踪靶标和治疗方案广泛应用于骨质疏松症治疗过程中。

关键词：骨质疏松症植物源性外泌体样纳米囊泡外泌体成骨细胞破骨细胞工程化外泌体

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利伐沙班在犬和猫临床应用的研究进展

动物医学进展 2025年第1期46卷 97-102页

作者：王炜江蓝路心怡付诗懿刘亦婷韦力煣俞峰刘波中国农业大学动物医学院北京100193 中国农业大学教学动物医院北京100193

血栓栓塞是犬、猫临床上多种疾病的并发症,可累及动脉或静脉,预后较差。目前兽医临床防治血栓栓塞可用的抗血栓药物种类有限,影响临床诊疗水平,引入新药具有实际意义。利伐沙班是一种新型非维生素K拮抗剂类口服抗凝药物,研究证明其能够... 详细信息

血栓栓塞是犬、猫临床上多种疾病的并发症,可累及动脉或静脉,预后较差。目前兽医临床防治血栓栓塞可用的抗血栓药物种类有限,影响临床诊疗水平,引入新药具有实际意义。利伐沙班是一种新型非维生素K拮抗剂类口服抗凝药物,研究证明其能够特异性抑制活性凝血因子X从而抑制血栓形成。近年来人医领域对利伐沙班的相关临床研究逐渐丰富,涉及单用利伐沙班或使用双通路抑制疗法防治不同类型的动、静脉血栓栓塞,可为其应用于兽医临床提供据。犬、猫临床使用利伐沙班的研究正相继开展,论文就犬、猫血栓栓塞疾病发病情况、防治现状,利伐沙班的药理学特性及其在人医、兽医领域的临床试验研究进展进行综述,以期为兽医临床上利伐沙班的进一步研究提供参考。

关键词：新型口服抗凝药利伐沙班血栓栓塞犬猫

Influence of Liquid Isoprene Rubber on Strain Softening of Carbon Black Filled Isoprene Rubber Nanocomposites

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Chinese Journal of Polymer Science 2021年第7期39卷 887-895页

作者： feng-yi Hou yi-Hu Song Qiang Zheng MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

The reinforcement of rubbers by nanoparticles is always accompanied with enhanced dissipation of mechanical energy upon large *** for solving the contradiction between improving reinforcement and reducing energy dissipation for rubber nanocomposites have not been well *** carbon black(CB)filled isoprene rubber(IR)/liquid isoprene rubber(LR)blend nanocomposites with similar crosslink density(ve)are prepared and influence of LR on the strain softening behaviors including Payne effect under large amplitude shear deformation and Mullins effect under cyclic uniaxial deformation is *** introduction of LR could improve the frequency sensitivity of loss modulus and reduce critical strain amplitude for Payne effect and loss modulus at the low ***,tuning ve and LR content allows reducing mechanical hysteresis in Mullins effect without significant impact on the mechanical *** investigation is illuminating for manufacturing nanocomposite vulcanizates with balanced mechanical hysteresis and reinforcement effect.

关键词： Rubber nanocomposites Stress softening Mechanical hysteresis Liquid rubber

A review of experimental and theoretical research on the deformation and failure behavior of rocks subjected to cyclic loading

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Journal of Rock Mechanics and Geotechnical Engineering 2021年第5期13卷 1203-1230页

作者： yi Liu feng Dai State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China

Rock engineering is highly susceptible to cyclic loads resulting from earthquakes,quarrying or *** the fatigue properties and failure mechanism of rocks is pivotal for long-term stability assessment of rock engineering *** far,significant progress has been gained on the mechanical characteristics of rocks subjected to cyclic *** providing a global insight of typical results and main features of rocks under cyclic loading conditions,this study comprehensively reviews the state-ofthe-art of deformation and failure mechanism and fatigue constitutive relationship of rocks subjected to cyclic loading in the past 60 ***,cyclic tests on rocks are classified into different types based on loading paths,loading parameters,loading types and environment ***,representative results are summarized and highlighted in terms of the fatigue response of rocks,including the deformation degradation,energy dissipation,damage evolution and failure characteristics;both laboratory testing and numerical results are presented,and various measurement techniques such as X-ray microcomputed tomography(micro-CT)and digital image correlation(DIC)are ***,the influences of cyclic loads on the mechanical characteristics of rocks are discussed,including the cyclic stress,frequency,amplitude and ***,constitutive relationships for rocks subjected to cyclic loading are outlined,in which typical fatigue constitutive models are compared and analyzed,regarding the elastoplastic model,the internal variable model,the energy-based damage model and the discrete element-based ***,some ambiguous questions and prospective research are interpreted and discussed.

关键词： Cyclic loads Mechanical properties Damage evolution Fatigue failure Constitutive relationship

Layout optimization of steel reinforcement in concrete structure using a truss-continuum model

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Frontiers of Structural and Civil Engineering 2023年第5期17卷 669-685页

作者： Anbang CHEN Xiaoshan LIN zi-Long ZHAO yi Min XIE Centre for Innovative Structures and Materials School of EngineeringRMIT UniversityMelbourne 3001Australia Institute of Solid Mechanics School of Aeronautic Science and EngineeringBeihang UniversityBeijing 100191China

Owing to advancement in advanced manufacturing technology,the reinforcement design of concrete structures has become an important topic in structural *** on bi-directional evolutionary structural optimization(BESO),a new approach is developed in this study to optimize the reinforcement layout in steel-reinforced concrete(SRC)*** approach combines a minimum compliance objective function with a hybrid trusscontinuum ***,a modified bi-directional evolutionary structural optimization(M-BESO)method is proposed to control the level of tensile stress in *** fully utilize the tensile strength of steel and the compressive strength of concrete,the optimization sensitivity of steel in a concrete–steel composite is integrated with the average normal stress of a neighboring *** demonstrate the effectiveness of the proposed procedures,reinforcement layout optimizations of a simply supported beam,a corbel,and a wall with a window are *** steel trajectories of SRC structures can be obtained using both *** area of critical tensile stress in concrete yielded by the M-BESO is more than 40%lower than that yielded by the uniform design and ***,the M-BESO facilitates a fully digital workflow that can be extremely effective for improving the design of steel reinforcements in concrete structures.

关键词： bi-directional evolutionary structural optimization steel-reinforced concrete concrete stress reinforcement method hybrid model

Characteristics of shell thickness in a slab continuous casting mold

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International Journal of Minerals,Metallurgy and Materials 2009年第1期16卷 25-31页

作者： Di-feng Wu Shu-sen Cheng zi-jian Cheng School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Steelmaking Plant Jiuquan Iron and Steel Co. Ltd. Jiayuguan 735100 China

The key to reduce shell breakout in the continuous casting process is to control shell thickness in the mold. A numerical simulation on the turbulent flow and heat transfer coupled with solidification in the slab mold using the volume of fluid （VOF） model and the enthalpy-porosity scheme was conducted and the emphasis was put upon the flow effect on the shell thickness profiles in longitudinal and transverse directions. The results show that the jet acts a stronger impingement on the shell of narrow face, which causes a zero-increase of shell thickness in a certain range near the impingement point. The thinnest shell on the slab cross-section locates primarily in the center of the narrow face, and secondly near the comer of the wide face. Nozzle optimization can obviously increase the shell thickness and make it more uniform.

关键词： continuous casting slab mold shell thickness nozzle optimization

Reliable calculations of nuclear binding energies by the Gaussian process of machine learning

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Nuclear Science and Techniques 2024年第6期35卷 130-144页

作者： zi-yi Yuan Dong Bai Zhen Wang Zhong-Zhou Ren School of Physics Science and Engineering Tongji UniversityShanghai 200092China College of Science Hohai UniversityNanjing 211100China Key Laboratory of Advanced Micro-Structure Materials Ministry of EducationShanghai 200092China

Reliable calculations of nuclear binding energies are crucial for advancing the research of nuclear physics. Machine learning provides an innovative approach to exploring complex physical problems. In this study, the nuclear binding energies are modeled directly using a machine-learning method called the Gaussian process. First, the binding energies for 2238 nuclei with Z > 20 and N > 20 are calculated using the Gaussian process in a physically motivated feature space, yielding an average deviation of 0.046 MeV and a standard deviation of 0.066 MeV. The results show the good learning ability of the Gaussian process in the studies of binding energies. Then, the predictive power of the Gaussian process is studied by calculating the binding energies for 108 nuclei newly included in AME2020. The theoretical results are in good agreement with the experimental data, reflecting the good predictive power of the Gaussian process. Moreover, the α-decay energies for 1169 nuclei with 50 ≤ Z ≤ 110 are derived from the theoretical binding energies calculated using the Gaussian process. The average deviation and the standard deviation are, respectively, 0.047 MeV and 0.070 MeV. Noticeably, the calculated α-decay energies for the two new isotopes ^ (204 )Ac(Huang et al. Phys Lett B 834, 137484(2022)) and ^ (207) Th(Yang et al. Phys Rev C 105, L051302(2022)) agree well with the latest experimental data. These results demonstrate that the Gaussian process is reliable for the calculations of nuclear binding energies. Finally, the α-decay properties of some unknown actinide nuclei are predicted using the Gaussian process. The predicted results can be useful guides for future research on binding energies and α-decay properties.

关键词： Nuclear binding energies decay Machine learning Gaussian process

Effect of Y-27632 on the cultured retinal neurocytes of rats

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International Journal of Ophthalmology(English edition) 2013年第1期6卷 15-18页

作者： Pei-Li feng Jing Wang zi-Jian Yang Xiao-Hong Liu yi-Sheng Zhong Department of Ophthalmology Ruijin Hospital Affiliated Medical SchoolShanghai Jiaotong University

AIM:To investigate the effect of Y-27632 on the survival and neurite outgrowth of the cultured retinal neurocytes. METHODS:After the postnatal day 2-3, Sprague-Dawley retinal neurocytes were cultured for 48 hours, the culture media was replaced with serum-free media (control group) and serum-free media contained 30μmol/L Y-27632 (Y-27632 group), and the cells were continually cultured another 48 hours. The cultured retinal neurocytes were identified with anti-neuron specific enolase (NSE) immunocytochemistry. The survival state of those cells was estimated by MTT assay, and the neurite outgrowth of those cells was evaluated by the computerized image-analysis system. RESULTS:Compared with the control group, the absorbance values of cells survival in Y -27632 group increased 12.90% and 33.33% respectively after 72 and 96 hours culture. Y-27632 had no significant effect on the diameter of cultured retinal neurocytes. Compared with the control group, Y-27632 induced a stable improvement of neurite outgrowth of retinal neurocytes after 72 and 96 hours culture (P =0.001). CONCLUSION:Y-27632 could promote the survival and neurite outgrowth of the early postnatal cultured retinal neurocytes.

关键词： Y-27632 retinal neurocytes cell culture neurites