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Weakly Noether Symmetry for Nonholonomic Systems of Chetaev's Type

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Communications in Theoretical Physics 2008年第6期49卷 1413-1416页

作者： MEI Feng-Xiang XIE jia-Fang gang tie-Qiang Department of Mechanics Beijing Institute of Technology Beijing 100081 China

In the paper [J. of Beijing Institute of Technology 26 （2006） 285] the authors provided the definition of weakly Noether symmetry. We now discuss the weakly Noether symmetry for non-holonomic system of Chetaev＇s type, and present expressions of three kinds of conserved quantities by weakly Noether symmetry. Finally, the application of this new result is shown by a practical example.

关键词： weakly Noether symmetry conserved quantity nonholonomic systems of Chetaev's type

Weak Noether Symmetry and non-Noether Conserved Quantities for General Holonomic Systems

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Communications in Theoretical Physics 2008年第10期50卷 844-846页

作者： XIE jia-Fang MEI Feng-Xiang gang tie-Qiang Department of Mechanics Beijing Institute of Technology Beijing 100081 China

A new kind of weak Noether symmetry for a general holonomic system is defined in such a way that themethods to construct Hojman conserved quantity and new-type conserved quantity are *** turns out that weintroduce a n... 详细信息

关键词： weak Noether symmetry non-Noether conserved quantity general holonomic system

Current status of drug therapy for chronic hepatitis B

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World Journal of Gastroenterology 2025年第2期31卷 1-12页

作者： Chuang jiang Zhi-Hong Zhang jia-Xin Li Division of Liver Surgery Department of General Surgery and Laboratory of Liver Surgeryand State Key Laboratory of Biotherapy and Collaborative Innovation Center of BiotherapyWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of General Surgery Dafang County People's HospitalBijie 551600Guizhou ProvinceChina

In this editorial,we comment on the article by Meng et *** hepatitis B(CHB)is a significant global health problem,particularly in developing *** B virus(HBV)infection is one of the most important risk factors for cirrhosis and hepatocellular *** and treatment of HBV are key measures to reduce *** present,drug therapy can effectively control virus replication and slow disease progression,but completely eliminating the virus remains a ***-HBV treatment is a long-term process,and there are many kinds of antiviral drugs with different mechanisms of action,it is essential to evaluate the safety and efficacy of these drugs to reduce side effects and improve patients’*** will summarize the current status of CHB drug treatment,hoping to provide a reference for the selection of clinical antiviral drugs.

关键词： Chronic hepatitis B Hepatitis B virus Anti virus Drug treatment Therapy

Predicting colorectal adenomatous polyps in patients with chronic liver disease: A novel nomogram

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World Journal of Gastroenterology 2025年第2期31卷 71-84页

作者： Yu-Qin Li Wen-Tao Kuai Lin Chen Ming-Hui Zeng Xue-Mei Tao jia-Xin Han Yue-Kui Wang Lian-Xin Xu Li-Ying Ge Yong-gang Liu Shuang Li Liang Xu Yu-Qiang Mi Clinical School of the Second People’s Hospital Tianjin Medical UniversityTianjin 300192China Department of Hepatology Tianjin Second People’s HospitalTianjin 300192China Department of Pathology Clinical School of the Second People’s HospitalTianjin 300110China Endoscopy Center Tianjin Second People’s HospitalTianjin 300192China

BACKGROUND Colorectal polyps are commonly observed in patients with chronic liver disease(CLD)and pose a significant clinical concern because of their potential for *** To explore the clinical characteristics of colorectal polyps in patients with CLD,a nomogram was established to predict the presence of adenomatous polyps(AP).METHODS Patients with CLD who underwent colonoscopy at Tianjin Second People’s Hospital from January 2020 to May 2023 were *** data including laboratory results,colonoscopy findings,and pathology reports were *** variables for the nomogram were identified through least absolute shrinkage and selection operator regression,followed by multivariate logistic *** performance of the model was evaluated using the area under the receiver area under curve,as well as calibration curves and decision curve *** The study enrolled 870 participants who underwent colonoscopy,and the detection rate of AP in patients with CLD was 28.6%.Compared to individuals without polyps,six risk factors were identified as predictors for AP occurrence:Age,male sex,body mass index,alcohol consumption,overlapping metabolic dysfunction-associated steatotic liver disease,and serum ferritin *** novel nomogram(AP model)demonstrated an area under curve of 0.801(95%confidence interval:0.756-0.845)and 0.785(95%confidence interval:0.712-0.858)in the training and validation *** curves indicated good agreement among predicted and actual probabilities(training:χ^(2)=11.860,P=0.157;validation:χ^(2)=7.055,P=0.530).The decision curve analysis underscored the clinical utility of the nomogram for predicting the risk of *** The AP model showed reasonable accuracy and provided a clinical foundation for predicting the occurrence of AP in patients with CLD,which has a certain predictive value.

关键词： Metabolic dysfunction associated steatotic liver disease Fatty liver Chronic liver disease Colorectal adenomas Hepatitis Risk factors

Passive activity enhances residual control ability in patients with complete spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2337-2347页

作者： Yanqing Xiao Mingming Gao Zejia He jia Zheng Hongming Bai jia-Sheng Rao Guiyun Song Wei Song Xiaoguang Li Beijing Key Laboratory for Biomaterials and Neural Regeneration Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Rehabilitation Evaluation China Rehabilitation Research CenterBeijingChina Cardiac Center Beijing Children’s HospitalCapital Medical UniversityBeijingChina The State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Department of Rehabilitation Engineering China Rehabilitation Science InstituteBeijingChina

Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury ***,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface *** this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord *** patients with chronic complete thoracic spinal cord injury were *** electromyography data from eight major leg muscles were acquired and compared before and after the passive activity *** results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of *** the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically *** findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.

关键词： complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task

Frontier applications of electrostatic accelerators

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Frontiers of physics 2013年第5期8卷 564-576页

作者： Ke-Xin Liu Yu-gang Wang tie-Shuan Fan Guo-Hui Zhang jia-Er Chen Institute of Heavy Ion Physics School of Physics ~ State Key Laboratory of Nuclear Physics and Technology Peking University Beijing 100871 China

Electrostatic accelerator is a powerflfl tool in many research fields, such as nuclear physics, radiation biology, material science *** and earth sciences. Two electrostatic accelerators, one is the single stage Vail de Gi＇aaff with terminal voltage of 4.5 MV and another one is tile EN tamteIn with terminal voltage of 6 MV, were installed in 1980s and had been put into operation since the early 1990s at tile Institute of Heavy Ion Physics. Marly applications have been carried out since then. These two accelerators are described and summaries of the most important applications on neutron physics and technology, radiation biology and material science, as well as accelerator mass spectrometry （AMS） are presented.

关键词： electrostatic accelerator application neutron radiation biology material science,accelerator mass spectrometry (AMS)

Mitophagy in acute central nervous system injuries:regulatory mechanisms and therapeutic potentials

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Neural Regeneration Research 2025年第9期20卷 2437-2453页

作者： Siyi Xu Junqiu jia Rui Mao Xiang Cao Yun Xu Department of Neurology Nanjing Drum Tower HospitalClinical College of Jiangsu UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalChinese Academy of Medical Science&Peking Union Medical CollegeNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases Nanjing UniversityNanjingJiangsu ProvinceChina jiangsu Key Laboratory for Molecular Medicine Medical School of Nanjing UniversityNanjingJiangsu ProvinceChina Nanjing Neurology Medical Center NanjingJiangsu ProvinceChina

Acute central nervous system injuries,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,traumatic brain injury,and spinal co rd injury,are a major global health *** optimal therapies and improving the long-term neurological functions of patients with acute central nervous system injuries are urgent *** are susceptible to damage after acute central nervous system injury,and this leads to the release of toxic levels of reactive oxygen species,which induce cell ***,a selective form of autophagy,is crucial in eliminating redundant or damaged mitochondria during these *** evidence has highlighted the significant role of mitophagy in acute central nervous system *** this review,we provide a comprehensive overview of the process,classification,and related mechanisms of *** also highlight the recent developments in research into the role of mitophagy in various acute central nervous system injuries and drug therapies that regulate *** the final section of this review,we emphasize the potential for treating these disorders by focusing on mitophagy and suggest future research paths in this area.

关键词： autophagy intracerebral hemorrhage ischemic stroke mitochondria mitochondrial biogenesis mitochondrial quality control mitophagy spinal cord injury subarachnoid hemorrhage traumatic brain injury

RGS4 promotes the progression of gastric cancer through the focal adhesion kinase/phosphatidyl-inositol-3-kinase/protein kinase B pathway and epithelial-mesenchymal transition

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World Journal of Gastroenterology 2025年第2期31卷 113-127页

作者： Peng-Yu Chen Pei-Yao Wang Bang Liu Yang-Pu jia Zhao-Xiong Zhang Xin Liu Dao-Han Wang Yong-jia Yan Wei-Hua Fu Feng Zhu Department of General Surgery Tianjin Medical University General HospitalTianjin Medical UniversityTianjin 300052China Department of General Surgery Jincheng People’s HospitalJincheng 048000Shanxi ProvinceChina

BACKGROUND Regulator of G protein signaling(RGS)proteins participate in tumor formation and metastasis by acting on theα-subunit of heterotrimeric G *** speci-fic effect of RGS,particularly RGS4,on the progression of gastric cancer(GC)is not yet *** To explore the role and underlying mechanisms of action of RGS4 in GC *** The prognostic significance of RGS4 in GC was analyzed using bioinformatics based public databases and verified by immunohistochemistry and quantitative polymerase chain reaction in 90 patients with *** assays were employed to assess the carcinogenic impact of RGS4,and the mechanism of its possible influence was detected by western blot analysis.A nude mouse xenograft model was established to study the effects of RGS4 on GC growth in *** RGS4 was highly expressed in GC tissues compared with matched adjacent normal *** RGS4 expression was correlated with increased tumor-node-metastasis stage,increased tumor grade as well as poorer overall survival in patients with *** experiments demonstrated that RGS4 knockdown suppressed GC cell proliferation,migration and ***,xenograft experiments confirmed that RGS4 silencing significantly inhibited tumor ***,RGS4 knockdown resulted in reduced phosphorylation levels of focal adhesion kinase,phosphatidyl-inositol-3-kinase,and protein kinase B,decreased vimentin and N-cadherin,and elevated *** High RGS4 expression in GC indicates a worse prognosis and RGS4 is a prognostic ***4 influences tumor progression via the focal adhesion kinase/phosphatidyl-inositol-3-kinase/protein kinase B pathway and epithelial-mesenchymal transition.

关键词： Gastric cancer Prognosis Regulator of G protein signaling 4 Focal adhesion kinase Epithelial-mesenchymal transition

Permeability measurement of the fracture-matrix system with 3D embedded discrete fracture model

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Petroleum Science 2022年第4期19卷 1757-1765页

作者： Bao jia Cheng-gang Xian State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Bejing)Beijing 102249China Unconventional Petroleum Research Institute China University of Petroleum(Bejing)Bejing 102249China

In this work, we performed the pulse-decay experiment on a fractured shale core and applied the 3 D embedded discrete fracture model(EDFM) to simulate the experiment process. The irregularly rough fracture surface was depicted in detail using a 3 D scanner. Then the fracture surface profile was imported in the discrete fracture network model to simulate the flow process in the fracture-matrix system realistically. History matching was efficiently performed to simultaneously obtain porosity and permeability for the matrix and fracture. Gas properties after applying nanopore confinement were obtained by modifying Sutton's viscosity correlation with sensitivity analysis on the pore diameter ranging from 2 to50 nm. Nanopore confinement results in low matched permeability due to viscosity reduction in the matrix-only porous media. The fracture-matrix system complicates the interpretation of nanopore confinement impact on flow behavior in shale reservoirs. Different scenarios of the highly fractured and matrix-dominated systems were discussed in detail by constructing the digital twin model.

关键词： Permeability Fracture Pulse-decay Shale Viscosity