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How to enhance the ability of mesenchymal stem cells to alleviate intervertebral disc degeneration

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World Journal of Stem Cells 2023年第11期15卷 989-998页

作者： qing-xiang zhang Min Cui Department of Critical Care Medicine Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina Department of Critical Care Medicine Wuhan Jinyintan HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430048Hubei ProvinceChina Department of Orthopedics Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022Hubei ProvinceChina

Intervertebral disc(ID)degeneration(IDD)is one of the main causes of chronic low back pain,and degenerative lesions are usually caused by an imbalance between catabolic and anabolic processes in the *** environment in which the ID is located is harsh,with almost no vascular distribution within the disc,and the nutrient supply relies mainly on the diffusion of oxygen and nutrients from the blood vessels located under the *** stability of its internal environment also plays an important role in preventing *** main feature of disc degeneration is a decrease in the number of *** stem cells have been used in the treatment of disc lesions due to their ability to differentiate into nucleus pulposus cells in a nonspecific anti-inflammatory *** main purpose is to promote their *** current aim of stem cell therapy is to replace the aged and metamorphosed cells in the ID and to increase the content of the extracellular *** treatment of disc degeneration with stem cells has achieved good efficacy,and the current challenge is how to improve this ***,we reviewed current treatments for disc degeneration and summarize studies on stem cell vesicles,enhancement of therapeutic effects when stem cells are mixed with related substances,and improvements in the efficacy of stem cell therapy by adjuvants under adverse *** reviewed the new approaches and ideas for stem cell treatment of disc degeneration in order to contribute to the development of new therapeutic approaches to meet current challenges.

关键词： Mesenchymal stem cells Intervertebral disc degeneration Extracellular vesicles Nucleus pulposus cells Tissue regeneration

Experimental study of the dynamics of a single cavitation bubble excited by a focused laser near the boundary of a rigid wall

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Journal of Hydrodynamics 2023年第5期35卷 942-953页

作者： xiang-qing zhang Xiao-fei zhang Xu Qiu Dan Gao Yu-ning zhang Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China China Atomic Energy Publishing and Media Co.LTD Beijing100048China China Institute of Nuclear Industry Strategy Beijing100048China National Institute of Energy Development Strategy North China Electric Power UniversityBeijing102206China

Based on high-speed photographic experiments,this study presents a detailed qualitative and quantitative analysis of the dynamics of a single cavitation bubble near the boundary of a rigid wall in asymmetric *** main findings are reported as follows:(1)The non-sphericity of the bubble interface decreases with increasing spacing between the bubble and the boundary,and the asymmetry of the bubble becomes more significant with increasing asymmetry angle.(2)The motion mode of the bubble cluster in the second oscillation cycle can be divided into two typical modes depending on the direction of movement.(3)The angle between the oblique jet pointing towards the upper wall surface and the horizontal direction in the second oscillation cycle decreases as the dimensionless spacing decreases.

关键词： Asymmetry boundary cavitation bubble high-speed photography jet non-sphericity

Diagonal Invariant Ideals of Topologically Graded C~*-algebras

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Chinese Quarterly Journal of Mathematics 2005年第4期20卷 338-341页

作者： XU qing-xiang zhang Xiao-bo Department of Mathematics Shanghai Normal University Shanghai 200234 China

We study diagonal invariant ideals of topologically graded C*-algebras over discrete groups. Since all Toeplitz algebras defined on discrete groups are topologically graded, the results in this paper have improved the... 详细信息

关键词： Fell bundle topologically graded C*-algebra diagonal invariant ideal

Research on downward crack closing of clay aquiclude in shallow coal seam safety mining

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Journal of Coal Science & Engineering(China) 2011年第3期17卷 349-354页

作者： HUANG qing-xiang zhang Wen-zhong School of Energy Engineering Key Laboratory of Western Mine Exploitation and Hazard Prevention of Ministry of Education Xi＇an University of Science and Technology Xi＇an 710054 China

The water resisting property of aquiclude is the key factor of water conservation and safety mining, and the mining induced cracks in aquiclude is major factor of water resisting property. The aquiclude is composed by loess layer and red clay layer in Yushuwan Coal Mine, and the water reaction property of clay and loess of aquiclude was tested by soil mechanics method. The permeability coefficient of the loess is 0.856 m/d and the clay is 0.434 m/d. The dilatability coefficient of the loess is 16.1% and the clay is 14.6%. Through physical solid-liquid simulation with whole stress-stain similarity, the distribution of ＂downward crack zone＂ and ＂upward crack zone＂ was found to be the major factor of aquiclude stability. The downward crack closing length is about 30% of the downward crack length. The expanding of clay and loess with water are principal factors of downward crack closing. At last, the mechanical model of downward crack closing was constructed, and the criterion of crack closing was put forward at all. This work will provides the theoretical base for aquiclude stability research and safety mining in shallow seam.

关键词： shallow coal seam simulation clay aquiclude downward crack crack closing

Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

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Petroleum Science 2024年第3期21卷 2048-2065页

作者： qing-Ping Li Jin-Ya zhang Jia-xiang zhang Yong-Xue zhang CNOOC Research Institute Company Limited Beijing100028China State Key Laboratory of Natural Gas Hydrate Beijing100028China College of Mechanical and Transportation Engineering China University of PetroleumBeijing2249China

Slug flow or high GVF(Gas Volume Fraction)conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps,endangering the safety of multiphase pump *** mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation ***(User Define Function)programs such as structural dynamics equations,alternating load equations,and pressure disturbance equations are embedded in numerical calculations,and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh *** results show that when the pressure disturbance occurs at the inlet,as the amplitude and period of the disturbance increase,the film thickness gradually *** the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely *** maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance *** mutual interference between enhanced waves does not have a significant impact on the film thickness,while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes,and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial *** with pressure disturbance conditions,alternating load conditions have a more significant impact on film thickness and *** actual operation,it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

关键词： Multiphase pump Liquid film seal Pressure disturbance wave Dynamic response characteristics

Laser-induced cavitation bubble near boundaries

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Journal of Hydrodynamics 2023年第5期35卷 858-875页

作者： Jia-xin Yu Xiao-yu Wang Jin-sen Hu Jun-wei Shen xiang-qing zhang Xiao-xiao Zheng Yu-ning zhang Zhi-feng Yao Key Laboratory of Power Station Energy Transfer Conversion and System(Ministry of Education) School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China China Fire and Rescue Institute Beijing102202China College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China

Laser-induced cavitation bubble has been widely used to investigate the mechanisms of hydraulic machinery cavitation erosion and to explore applications in atomization, alloy strengthening, ultrasonic chemistry, biomedicine, surface cleaning and materials processing. This paper consolidates existing research findings on the cavitation bubble dynamics near different boundaries and provides insights for future research work. Firstly, the dynamics of a single cavitation bubble in an infinite field is presented. Subsequently, the focus shifts to the dynamics of cavitation bubble near a rigid wall, angular walls, particles and hydrofoil. Lastly, the paper delves into the dynamics of cavitation bubble within a droplet, revealing the microscopic mechanism of droplet breakup induced by cavitation bubble.

关键词： Laser-induced cavitation bubble bubble dynamics bubble-particle interactions droplet splash

Modeling of LF refining process:a review

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Journal of Iron and Steel Research International 2024年第2期31卷 289-317页

作者： Zi-cheng Xin Jiang-shan zhang Kai-xiang Peng Jun-guo zhang Chun-hui zhang qing Liu State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing100083China School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing100083China Tangshan Branch Hebei Iron and Steel Co.Ltd.Tangshan063000HebeiChina Xinjiang Bayi Iron and Steel Co. Ltd.Baosteel GroupWulumuqi830022XinjiangChina

With the increasing demand for energy conservation and emission reduction,more attentions have been paid to the intelligentization,greenization and low carbonization during the transformation and upgrading of steelmaking *** furnace(LF)refining is one of the key procedures in steelmaking process and has been widely used in steelmaking plants for its high equipment matching degree,low equipment investment and outstanding refining *** to the main tasks of LF refining process,the modeling methods of temperature prediction model,slag-making model,alloying model,argon blowing model and model of inclusions behavior were systematically reviewed,and the advantages and disadvantages of each modeling method were *** addition,the technical framework for the future has also been proposed based on existing works,including classification of raw materials,graphic representation of knowledge,introduction,upgradation and management of device/equipment,customization of steelmaking,modeling of refining process,synergy of models,intelligentization of decision-making,automation of control,and digitization of processes and operations,aiming to provide a reference for the modeling and intelligent development of LF refining process.

关键词： LF refining Temperature prediction Slag-making Alloying Argon blowing Inclusion behavior Modeling method

Privacy Protection for Blockchain-Based Healthcare IoT Systems: A Survey

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1757-1776页

作者： Minfeng Qi Ziyuan Wang qing-Long Han Jun zhang Shiping Chen Yang xiang School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyHawthorn3122VictoriaAustralia Faculty of Data Science City University of MacaoMacaoChina CSIRO Data61 SydneyNew South WalesAustralia

To enable precision medicine and remote patient monitoring,internet of healthcare things(IoHT)has gained significant interest as a promising *** the widespread use of IoHT,nonetheless,privacy infringements such as IoHT data leakage have raised serious public *** the other side,blockchain and distributed ledger technologies have demonstrated great potential for enhancing trustworthiness and privacy protection for IoHT *** this survey,a holistic review of existing blockchain-based IoHT systems is conducted to indicate the feasibility of combining blockchain and IoHT in privacy *** addition,various types of privacy challenges in IoHT are identified by examining general data protection regulation(GDPR).More importantly,an associated study of cutting-edge privacy-preserving techniques for the identified IoHT privacy challenges is ***,several challenges in four promising research areas for blockchain-based IoHT systems are pointed out,with the intent of motivating researchers working in these fields to develop possible solutions.

关键词： Blockchain internet of healthcare things(IoHT) privacy-preserving techniques(PPTs).

How to interpret low human chorionic gonadotropin levels in cerebrospinal fluid of patients with intracranial germinoma？

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Chinese Medical Journal 2013年第24期126卷 4809-4810页

作者： CONG Lu TIAN Cheng-lin WANG xiang-qing DONG Zhao zhang Jia-tang YU Sheng-yuan Department of Neurology Chinese People's Liberation Anny General Hospital Beijing 100853 China

Human chorionic gonadotropin （hCG） level in cerebrospinal fluid （CSF hCG） is very useful for thediagnosis of intracranial germinoma. We have previously reported on two patients with germinoma located in the basal ganglia. Their CSF hCG levels were extremely low upon presentation.1 However, significantly increased CSF hCG levels were detected when these two patients had a relapse. The experience acquired in these two cases is helpful to appropriately interpret the CSF hCG levels that are used to detect intracranial germinoma, evaluate the effectiveness of treatment and monitor recurrence.

关键词： germinoma, human chorionic gonadotropin cerebrospinal fluid