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Effects of local thickness defects on the buckling of micro-beam

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Applied Mathematics and Mechanics(English Edition) 2022年第5期43卷 729-742页

作者： Andi LAI bing zhao Xulong PENG Chengyun LONG Department of Mechanics School of Civil EngineeringChangsha University of Science and TechnologyChangsha 410114China

A buckling model of Timoshenko micro-beam with local thickness defects is established based on a modified gradient *** introducing the local thickness defects function of the micro-beam,the variable coefficient differential equations of the buckling problem are obtained with the variational *** the eigensolution series of the complete micro-beam with the Galerkin method,we obtain the critical load and buckling modes of the micro-beam with *** results show that the depth and location of the defect are the main factors affecting the critical load,and the combined effect of boundary conditions and defects can significantly change the buckling mode of the *** effect of defect location on buckling is related to the axial gradient of the rotation angle,and defects should be avoided at the maximum axial gradient of the rotation *** model and method are also applicable to the static deformation and vibration of the micro-beam.

关键词： Timoshenko micro-beam local thickness defect modified gradient elasticity buckling

Deformation critical threshold estimation of Xiaowan ultrahigh arch dam with time-varying grey model

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Water Science and Engineering 2023年第3期16卷 302-312页

作者： Er-feng zhao Bo Li Hao Chen bing-bing Nie State Key Laboratory of Hydrology–Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Huaneng Lancang River Hydropower Co. Ltd.Kunming 650214China

The structural behavior of the Xiaowan ultrahigh arch dam is primarily influenced by external loads and time-varying characteristics of dam concrete and foundation rock mass during long-term operation. According to overload testing with a geological model and the measured time series of installed perpendicular lines, the space and time evolution characteristics of the arch dam structure were analyzed, and its mechanical performance was evaluated. Subsequently, the deformation centroid of the deflective curve was suggested to indicate the magnitude and unique distribution rules for a typical dam section using the measured deformation values at multi-monitoring points. The ellipse equations of the critical ellipsoid for the centroid were derived from the historical measured time series. Hydrostatic and seasonal components were extracted from the measured deformation values with a traditional statistical model, and residuals were adopted as a grey component. A time-varying grey model was developed to accurately predict the evolution of the deformation behavior of the ultrahigh arch dam during future operation. In the developed model, constant coefficients were modified so as to be time-dependent functions, and the prediction accuracy was significantly improved through introduction of a forgetting factor. Finally, the critical threshold was estimated, and predicted ellipsoids were derived for the Xiaowan arch dam. The findings of this study can provide technical support for safety evaluation of the actual operation of ultrahigh arch dams and help to provide early warning of abnormal changes.

关键词： Arch dam Deformation behavior Evolution Critical threshold Grey model

Aerobic exercise suppresses hepatocellular carcinoma by downregulating dynamin-related protein 1 through PI3K/AKT pathway

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Journal of Integrative Medicine 2021年第5期19卷 418-427页

作者： Tong zhao bing-jie Guo Chu-lan Xiao Jiao-jiao Chen Can Lü fan-fu fang Bai Li School of Traditional Chinese Medicine Naval Medical UniversityShanghai 200433China Nanjing University of Chinese Medicine.Nanjing 210023 Jiangsu ProvinceChina

Objective: Exercise, as a common non-drug intervention, is one of several lifestyle choices known to reduce the risk of cancer. Mitochondrial division has been reported to play a key role in the occurrence and transformation of hepatocellular carcinoma(HCC). This study investigated whether exercise could regulate the occurrence and development of HCC through ***: Bioinformatics technology was used to analyze the expression level of dynamin-related protein1(DRP1), a key protein of mitochondrial division. The effects of DRP1 and DRP1 inhibitor(mdivi-1) on the proliferation and migration of liver cancer cells BEL-7402 were observed using cell counting kit-8, plate colony formation, transwell cell migration, and scratch experiments. Enzyme-linked immunosorbent assay, Western blot and real-time polymerase chain reaction were used to detect the expression of DRP1 and its downstream phosphoinositide 3-kinase(PI3 K)/protein kinase B(AKT) pathway. A treadmill exercise intervention was tested in a nude mouse human liver cancer subcutaneous tumor model expressing different levels of DRP1. The size and weight of subcutaneous tumors in mice were detected before and after ***: The expression of DRP1 in liver cancer tissues was significantly upregulated compared with normal liver tissues(P<0.001). The proliferation rate and the migration of BEL-7402 cells in the DRP1 overexpression group were higher than that in the control group. The mdivi-1 group showed an inhibitory effect on the proliferation and migration of BEL-7402 cells at 50 lmol/L. Aerobic exercise was able to inhibit the expression of DRP1 and decrease the size and weight of subcutaneous tumors. Moreover,the expression of phosphorylated PI3 K(p-PI3 K) and phosphorylated AKT(p-AKT) decreased in the exercise group. However, exercise could not change p-PI3 K and p-AKT levels after knocking down DRP1 or using mdivi-1 on subcutaneous ***: Aerobic exercise can suppress the development of

关键词： Aerobic exercise Hepatocellular carcinoma Dynamin-related protein PI3K/AKT pathway

Facile suspension culture protocol of the liver biliary organoids

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Bio-Design and Manufacturing 2023年第1期6卷 74-81页

作者： Jin Chen Jiting Zhang Li Yang bing zhao State Key Laboratory of Genetic Engineering School of Life SciencesHuman Phenome InstituteZhongshan HospitalFudan UniversityShanghai 200438China

Introduction Why do we focus on human liver biliary organoids?The three-dimensional(3D)organoid approach is emerging as a powerful tool for basic study and biomedical applications due to its excellent recapitulation of the structure and functions of the primary tissues[1-3].Liver biliary organoids are derived from the biliary tree,which includes the intrahepatic bile duct(IHBD)and extrahepatic bile duct(EHBD).

关键词： biliary liver Liver

Impact of the number of examined lymph nodes on outcomes in patients with lymph node-negative gallbladder carcinoma

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World Journal of Gastroenterology 2018年第26期24卷 2886-2892页

作者： Dong-Xu fan Rong-Wei Xu Yong-Cheng Li bing-Qing zhao Ming-Yu Sun Department of Vascular surgery First Affiliated Hospital of Jiamusi University Department of Vascular Surgery Shandong Provincial Qianfoshan Hospital Shandong University Department of Medical Oncology Xuzhou Central Hospital The Affiliated Xuzhou Hospital of Medical College of Southeast University Department of Surgery Tianjin Second People's Hospital Department of Breast Surgery Xuzhou Central Hospital The Affiliated Xuzhou Hospital of Medical College of Southeast University

AIM To determine whether the number of examined lymph nodes(LNs) is correlated with the overall survival of gallbladder carcinoma(GBC) patients. METHODS Patients were collected from the Surveillance Epidemiology and End Results database(2004-2013) and categorized by the number of LNs into six groups: 1 LN, 2 LNs, 3 LNs, 4 LNs, 5 LNs, and ≥ 6 LNs. Survival curves for overall survival were plotted with a KaplanMeier analysis. The log-rank test was used for univariate *** In a cohort of 893 patients, the median number of examined LNs was two for the entire cohort. The survival for the 1 LN group was significantly poorer than those of the stage Ⅰ and Ⅱ disease groups and for the entire cohort. By dichotomizing the number of LNs from 1 to 6, we found that the minimum number of LNs that should be examined was four for stage Ⅰ, four or five for stage Ⅱ, and six for stage ⅢA disease. Therefore, for the entire cohort, the number of examined LNs should be at least six, which is exactly consistent with the American Joint Committee on Cancer *** The examination of higher numbers of LNs is associated with improved survival after resection surgery for N0 GBC. The guidelines for GBC surgery, which recommend that six LNs be examined at least, are statistically valid and should be applied in clinical practice widely.

关键词： Gallbladder carcinoma Lymph node N0 stage Prognostic factor

Einstein-Podolsky-Rosen Entanglement and Quantum Nonlocality for an Electron in a Uniform Magnetic Field

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Chinese Physics Letters 2000年第5期17卷 316-318页

作者： fan Hong-Yi CHEN Zeng-bing Department of Applied Physics Shanghai Jiao Tong UniversityShanghai 200030 Department of Material Science and Engineering University of Science and Technology of ChinaHefei 230026

Ws show that there exists the precise Einstein-Podolsky-Rosen entanglement for an electron in a uniform magnetic ***,the x-and y-coordinates of the electron as well as the corresponding canonical momenta px and Pv become sharply correlated,which is a novel fact unnoticed *** a harmonic potential is added to the system,the original vacuum state of the system becomes a squeezed vacuum state,whose quantum nonlocality is then demonstrated.

关键词： Einstein vacuum Uniform

Discrete Methods Based on First Order Reversal Curves to Identify Preisach Model of Smart Materials

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Chinese Journal of Aeronautics 2007年第2期20卷 157-161页

作者： LI fan zhao Jian-hui School of Instrument Science and Opto-electronics Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

Preisach model is widely used in modeling of smart materials. Although first order reversal curves （FORCs） have often found applications in the fields of physics and geology, they are able to serve to identify Preisach model. In order to clarify the relationship between the Preisach model and the first order reversal curves, this paper is directed towards：（1） giving the reason a first order reversal curve is introduced; （2） presenting, for identifying Preisach model, two discrete methods, which are analytically based on first order reversal curves. Herein also is indicated the solution＇s uniqueness of these two identifying methods. At last, the validity of these two methods is verified by simulating a real smart actuator both methods have been applied to.

关键词： first order reversal curve Preisach model smart material discrete identify

Natural and human-induced decline and spatio-temporal differentiation of terrestrial water storage over the Lancang-Mekong River Basin

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Journal of Geographical Sciences 2025年第1期 112-138页

作者： CHEN Junxu WANG Yuan zhao Zhifang fan Yunjiang LUO Xiaochuan YI Lu FENG Siqi YANG Liang Emlyn Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Yunnan University International Joint Research Center for Karstology Yunnan University School of Engineering Westlake University Department of Geography Ludwig Maximilian University of Munich (LMU)

Due to water conflicts and allocation in the Lancang-Mekong River Basin(LMRB), the spatio-temporal differentiation of total water resources and the natural-human influence need to be clarified. This work investigated LMRB's terrestrial water storage anomaly(TWSA) and its spatio-temporal dynamics during 2002–2020. Considering the effects of natural factors and human activities, the respective contributions of climate variability and human activities to terrestrial water storage change(TWSC) were separated. Results showed that:(1) LMRB's TWSA decreased by 0.3158 cm/a.(2) TWSA showed a gradual increase in distribution from southwest of MRB to middle LMRB and from northeast of LRB to middle LMRB. TWSA positively changed in Myanmar while slightly changed in Laos and China. It negatively changed in Vietnam, Thailand and Cambodia.(3) TWSA components decreased in a descending order of soil moisture, groundwater and precipitation.(4) Natural factors had a substantial and spatial differentiated influence on TWSA over the LMRB.(5) Climate variability contributed 79% of TWSC in the LMRB while human activities contributed 21% with an increasing impact after 2008. The TWSC of upstream basin countries was found to be controlled by climate variability while Vietnam and Cambodia's TWSC has been controlled by human activities since 2012.

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Carrier Envelope Phase Effect of a Long Duration Pulse in the Low Frequency Region

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Chinese Physics Letters 2014年第4期31卷 37-40页

作者： zhao Xi YANG Yu-Jun LIU Xue-Shen WANG bing-bing Institute of Atomic and Molecular Physics Jilin University Changchun 130012 Laboratory of Optical Physics Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080

Using the characteristic of small energy difference between two high Rydberg states, we theoretically investigate the carrier envelope phase （CEP） effect in a bound-bound transition of an atom in a low-frequency long laser pulse with tens of optical cycles. Particularly, we first prepare a Rydberg state of a hydrogen-like atom by a laser field with the resonant frequency between this state and the ground state. Then by using a low-frequency long laser pulse interacting with this Rydberg atom, we calculate the population of another Rydberg state nearby this Rydberg state at the end of the laser pulse and find that the population changes dramatically with the CEP of the low-frequency pulse. This CEP effect is attributed to the interference between the positive-frequency and negative-frequency components in one-photon transition. These results may provide a method to measure the CEP value of a long laser pulse with low frequency.

关键词： RYDBERG states BOUND-bound transitions LASER pulses HYDROGEN PHOTONS