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lie Symmetry and Conserved Quantities for Mechanical-Electrical Systems

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Communications in Theoretical Physics 2008年第6期49卷 1417-1420页

作者： JING hong-xing li Yuan-Cheng College of Physics Science and Technology China University of Petroleum （East China） Dongying 257061 China

In this paper, we study lie symmetry and conserved quantities for a mechanical-electrical system. The criterion of the lie symmetry for this system is given. The generalized Hojman conserved quantity and generalized Lutzky conserved quantity deduced from the lie symmetry for the system are obtained. An example is presented to illustrate the results.

关键词： mechanical-electrical system lie symmetry generalized Hojman conserved quantity, generalized Lutzky conserved quantity

Mei Symmetry and Lutzky Conserved Quantity for Nonholonomic Mechanical System with Unilateral Constraints

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Communications in Theoretical Physics 2008年第3期49卷 575-578页

作者： JING hong-xing li Yuan-Cheng College of Physics Science and Technology China University of Petroleum （East China） Dongying 257061 China

In this paper, we study the Mei symmetry which can result in a Lutzky conserved quantity for nonholonomic mechanical system with unilateral constraints. The definition and the criterion of the Mei symmetry for the system are given. The necessary and sufficient condition under which the Mei symmetry is a lie symmetry for the system is obtained. A Lutzky conserved quantity deduced from the Mei symmetry is gotten. An example is given to illustrate the application of our results.

关键词： nonholonomic mechanical system unilateral constraint Mei symmetry Lutzky conserved quantity

lie Symmetry and Generalized Mei Conserved Quantity for Nonconservative Dynamical System

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Communications in Theoretical Physics 2008年第5期49卷 1148-1150页

作者： JING hong-xing li Yuan-Cheng College of Physical Science and Technology China University of Petroleum （East China） Dongying 257061 China

Based on the total time derivative along the trajectory of the system, for noneonservative dynamical system, the generalized Mei conserved quantity indirectly deduced from the lie symmetry of the system is studied. Firstly, the lie symmetry of the system is given. Then, the necessary and sumeient condition under which the lie symmetry is a Mei symmetry is presented and the generalized Mei conserved quantity indirectly deduced from the lie symmetry of the system is obtained. Lastly, an example is given to illustrate the application of the result.

关键词： lie symmetry Mei symmetry generalized Mei conserved quantity nonconservative dynamicalsystem

Epigenetic regulation of adipocyte differentiation and adipogenesis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第10期11卷 784-791页

作者： hong-xing li Lei XIAO Cheng WANG Jia-li GAO Yong-gong ZHAI Key Laboratory for Cell Proliferation and Regulation Biology of Ministry of Education College of Life Sciences Beo'ing Normal University Beijing 100875 China Reproductive Medicine Research Center the First Hospital of Lanzhou University Lanzhou 730000 China Beijing Key Laboratory of Engineered Drug and Biotechnology College of Life Sciences Beijing Normal University Beijing 100875 China Biomedicine Research Institute College of Life Sciences Beijing Normal University Beijing 100875 China Feed Research Institute Chinese Academy of Agricultural Sciences Beijing 100081 China

It is generally agreed that adipocytes originate from mesenchymal stem cells in what can be divided into two processes:determination and *** the past decade,many factors associated with epigenetic signals have been proved to be pivotal for the appropriate timing of adipogenesis progression.A large number of coregulators at critical gene promoters set up specific patterns of DNA methylation,histone acetylation and methylation,and nucleosome rearrangement,that act as an epigenetic code to modulate the correct progress of adipocyte differentiation and adipogenesis during *** this review,we focus on the functions and roles of epigenetic processes in preadipocyte differentiation and adipogenesis.

关键词： Epigenetic regulation Histone modification DNA methylation Differentiation Adipogenesis

Frequency-dependent reflection of elastic wave from thin bed in porous media

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Chinese Physics B 2020年第6期29卷 249-254页

作者： hong-xing li Chun-Hui Tao Cai liu Guang-Nan Huang Zhen-An Yao State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200240China Department of Geophysics Jilin UniversityChangchun 130026China

The reflection of elastic wave from thin bed in porous media is important for oil and gas reservoir seismic *** equations for calculating frequency-dependent reflection amplitude versus incident angle(FDAVA)from thin bed in porous media are obtained based on porous media *** conclusions are obtained from numerical analysis,specifically,slow compression wave may be ignored when considering boundary conditions in most situations;the dispersion of reflection from thin bed is much higher than that from thick layer and is periodic in frequency domain,which is affected by the thickness of thin bed,velocity,and incident angle;the reflection amplitude envelope in frequency domain decays exponentially,which is affected by the thickness of thin bed,attenuation,and incident angle;the reflection amplitude increases with thickness of thin bed increasing,and then it decreases when the thickness reaches to a quarter of wavelength.

关键词： frequency-dependent reflection porous media thin bed reservoir

Tetrabromobisphenol A‑bis(2,3-dibromopropyl ether)impairs Postnatal Testis Development in Mice:The Microtubule Cytoskeleton as a Sensitive Target

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Environment & Health 2023年第3期1卷 168-179页

作者： Yuan-Yuan li Yi-Ming Xiong Shu-Yan Zhang Jing-lin Deng Qiao Xue xing-Wang Hou Wen-Bin liu xing-hong li Zhan-Fen Qin State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China

Tetrabromobisphenol A-bis(2,3-dibromopropyl ether)(TBBPA-BDBPE),a widely used flame retardant,has been frequently detected in various environmental compartments,but its health hazard remains largely ***,we investigated the adverse effects of TBBPA-BDBPE(50 and 1000μg/kg/day)on postnatal testis development in CD-1 mice and the underlying *** the first week of maternal exposure,neonatal mice in the high-dose group exhibited reduced seminiferous tubule area,fewer Sertoli cells and germ cells,and damaged microtubules in Sertoli cells;even microtubule damage was also observed in the low-dose *** exposure extended to adulthood,male offspring in the high-dose group presented more remarkable alterations in reproductive parameters,including reduced sperm count;in the low-dose group,microtubule damage was also observable,along with blood−testis barrier *** molecular docking analysis and tubulin polymerization assay indicated that TBBPA-BDBPE could interact with tubulin and disrupt its ***,we observed attenuated microtubules in mouse Sertoli cells in vitro(TM4)following TBBPABDBPE treatment,suggesting that TBBPA-BDBPE impaired testis development possibly by interfering with tubulin *** study not only highlights the male reproductive hazard of TBBPA-BDBPE but also greatly improved the understanding of the molecular mechanism for male reproductive toxicity of chemicals.

关键词： tetrabromobisphenol A-bis(2 3-dibromopropyl ether) testis development Sertoli cells microtubule reproductive toxicity

Position of increased signal intensity in the spinal cord on MR images： does it predict the outcome of cervical spondylotic myelopathy？

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Chinese Medical Journal 2009年第12期122卷 1418-1422页

作者： SHEN hong-xing li ling YANG Zhi-gao HOU Tie-sheng Department of Orthopaedics Changhai Hospital Second Military Medical University Shanghai 200433 China

Background Increased signal intensity （ISI） in the spinal cord on T2-weighted MR images has been reported in some previous researches, however no study focused on the position of the ISI in the spinal cord and its potential value. The aim of this study was to investigate the correlation between ISI position and the outcome of surgical treatment for cervical spondylotic myelopathy （CSM） patients. Methods A retrospective study was conducted. Pre- and post-operative clinical status was evaluated by modified Japanese Orthopaedic Association （JOA） score. ISI was evaluated according to the T2-weighted sequences. The JOA score and the recovery ratios among patients with ISI in gray matter （group A）, in both gray and white matter （group B）, and ISI-negative group were compared. Results Totally 64 patients were enrolled in this retrospective study. Preoperative JOA score of ISI positive and negative group had significant difference, but the recovery ratios had no significant difference （the recovery ratios of the two groups in week 1, week 26, and week 104 were （21.54±14.65）%, （50.56±14.76）%, （59.23±13.08）% and （20.25±14.32）%, （54.46±3.16）% and （61.26±29.4）%, respectively; P 〉0.05）. The recovery ratios of negative group and group A in week 104 were superior to group B （the recovery ratios of negative group, group A, and group B in week 104 were （61.26±29.49）%, （65.35±11.36）%, and （50.33±10.20）%, respectively; P 〈0.05）. Conclusions Patients with ISI in the gray matter alone on T2-weighted MR images did not have significantly different surgical outcomes compared with those without ISI. Patients with ISI in both gray and white matter had surgical outcomes that were worse than those without ISI.

关键词： cervical spondylotic myelopathy increased signal intensity Japanese Orthopaedic Association score prognosis recovery ratio

Epigenetic regulatory differentiation of hematopoietic stem cells to the red lineage

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Reproductive and Developmental Medicine 2024年第3期8卷 169-177页

作者： hong-xing li Yi-hong Chai Xiao-hong Sun Xiao-Xia He Ya-Ming Xi The First School of Clinical Medicine Lanzhou UniversityLanzhou 730000China Key Laboratory for Reproductive Medicine and Embryo of Gansu Province Lanzhou 730000China Department of Hematology The First Hospital of Lanzhou UniversityLanzhou 730000China

The differentiation process from hematopoietic stem cells(HSCs)to mature red blood cells(RBCs)is characterized by remarkable precision and is tightly controlled from the initial lineage commitment to eventual terminal *** is the dynamic journey of HSCs through various functional and phenotypic *** physiological course of erythrogenesis is intricately linked to significant changes in chromatin accessibility,necessitating precise coordination of transcription factors and epigenetic *** review presents a comprehensive overview of recent investigations into the molecular-level epigenetic regulatory factors that influence the differentiation of the erythroid *** encompasses the exploration of transcriptional,post-transcriptional,and post-translational regulatory *** intricate interplay of epigenetic and transcriptional regulatory networks in erythroid differentiation not only enhances our understanding of this fundamental biological process but also provides valuable insights into the underlying mechanisms contributing to the pathogenesis of disorders associated with abnormal erythroid *** findings hold significant promise for the development of novel therapeutic strategies to address these diseases and improve patient outcomes.

关键词： Hematopoietic stem cells Differentiation Epigenetics Post-translational regulation

Fertility Preservation in Cancer Patients

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Reproductive and Developmental Medicine 2021年第1期5卷 44-54页

作者： Yuan-Xue Jing li-li Zhang hong-xing li Feng Yue Nai Hui Wang Shi-Long Xue Yi-Qing Wang Xue-hong Zhang Reproductive Medicine Center The First Hospital of Lanzhou UniversityLanzhou 730000China Key Laboratory for Reproductive Medicine and Embryo of Gansu Lanzhou 730000China

Traditional radiotherapy and chemotherapy often cause irreversible damage to the fertility and endocrine function of cancer *** current methods of fertility preservation include freezing the sperms of adult and adolescent males after puberty;freezing the embryos,oocytes,and ovarian tissue of females;and drug intervention and fertility preservation *** article reviews fertility preservation in cancer patients with respect to current methods,indications,and some more recently developed methods that remain under investigation.

关键词： Cryopreservation of Ovarian Tissue Cryopreservation of Testis Tissue Cryopreserved Embryos and Oocytes Fertility Preservation In vitro Maturation