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Correlation between ECT2 gene expression and methylation change of ECT2 promoter region in pancreatic cancer

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Hepatobiliary & Pancreatic Diseases International 2008年第5期7卷 533-538页

作者： Zhang, Mang-Li Lu, Sen zhou, lin Zheng, Shu-Sen Zhejiang Univ Sch Med Affiliated Hosp 1 Dept Hepatobiliary & Pancreat Surg Hangzhou 310003 Zhejiang Peoples R China

BACKGROUND: Pancreatic cancer is closely related to epigenetic abnormality. The epithelial cell transforming sequence 2 gene (ECT2) plays a critical role in Rho activation during cytokinesis, and thus may play a role in the pathogenesis of pancreatic cancer. In this study, we investigated the relationships between aberrant expression and epigenetic changes of the ECT2 gene in pancreatic cancer. METHODS: Four cell lines (PANC-1, Colo357, T3M-4 and PancTu I) and pancreatic ductal adenocarcinoma (PDAC) tissues were used for mRNA detection. After restriction isoschizomer endonucleases (Msp I/Hpa II) were used to digest the DNA sequence (5'-CCGG-3'), PCR was made to amplify the product. And RT-PCR was applied to determine the expression of the gene. RESULTS: The mRNA expression of the ECT2 gene was higher in pancreatic tumor tissue than in normal tissue. The gene was also expressed in the 4 PDAC cell lines. The methylation states of the upstream regions of the ECT2 gene were almost identical in normal, tumor pancreatic tissues, and the 4 PDAC cell lines. Some of the 5'-CCGG-3' areas in the upstream region of ECT2 were methylated, while others were unmethylated. CONCLUSIONS: The oncogene ECT2 is overexpressed in pancreatic tumor tissues as verified by RT-PCR detection. The methylation status of DNA in promoter areas is involved in the gene expression, along with other factors, in pancreatic cancer.

关键词： pancreatic neoplasms epithelial cell transforming sequence 2 gene epigenesis, genetic

Ion beam figuring of continuous phase plates based on the frequency filtering process

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Frontiers of Mechanical Engineering 2017年第1期12卷 110-115页

作者： Mingjin XU Yifan DAI Xuhui XIE lin zhou Shengyi LI Wenqiang PENG College of Mechatronics Engineering and Automation NationalUniversity of Defense Technology Changsha 410073 China College of Basic Education for Command Officer National Universityof Defense Technology Changsha 410073 China

Ion beam figuring （IBF） technology is an effective technique for fabricating continuous phase plates （CPPs） with small feature structures. This study proposes a multi-pass IBF approach with different beam diameters based on the frequency filtering method to improve the machining accuracy and efficiency of CPPs during IBF. We present the selection principle of the frequency filtering method, which incorporates different removal functions that maximize material removal over the topographical frequencies being imprinted. Large removal functions are used early in the fabrication to figure the surface profile with low frequency. Small removal functions are used to perform final topographical correction with higher fre- quency and larger surface gradient. A high-precision surface can be obtained as long as the filtering frequency is suitably selected. This method maximizes the high removal efficiency of the large removal function and the high corrective capability of the small removal function. Consequently, the fast convergence of the machining accuracy and efficiency can be achieved.

关键词： ion beam figuring (IBF) continuous phaseplates (CPPs) machining accuracy machining efficiency,frequency filtering process

GENERAL INTERPOLATION FORMULAS FOR SPACES OF DISCRETE FUNCTIONS WITH NONUNIFORM MESHES

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Journal of Computational Mathematics 1995年第1期13卷 70-93页

作者： zhou Yu-lin(Institute of Applied Physics and Computational Mathematics, Beijing, China ) 北京应用物理和计算数学所北京

The unequal meshsteps are unavoidable in general for scientific and engineering computations especially in large Scale computations. The analysis of difference schemes with nonuniform meshes is very rare even by use of fully heuristic methods. For the purpose of the systematic and theoretical study of the finite difference method with nonuniform meshes for the problems of partial differential equations, the general interpolation formulas for the spaces of discrete functions of one index with unequal meshsteps are established in the present work. These formulas give the connected relationships among the norms of various types, such as' the sum of powers of discrete values, the discrete maximum modulo, the discrete Holder and Lipschitz coefficients.

关键词： Discrete functions Interpolation Mathematical constants Partial differential equations Difference quotients Real lines Finite difference methods Mathematical theorems Ratios Engineering

Study on adverse effects of groundwater level rising induced by land creation engineering in hilly and gully area of the Loess Plateau

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Journal of Mountain Science 2019年第12期16卷 2739-2753页

作者： DUAN Xu DONG Qi YE Wan-jun zhou Jia-lin OH Erwin School of Architectural and Civil Engineering Xi'an University of Science and TechnologyXi'anShaanxi 710054China Shaanxi Science&Technology Holding Group Co. Ltd.Xi'anShaanxi 710054China State Key Laboratoiij for Strength and Vibration of Mechanical Structures Xi'an Jiaotong UniversityXi'an 710049China School of Engineering Griffith UniversityGold Coast 7222Australia

Land creation projects have been implemented in China to expand urban space in mountainous *** addition to the predictable settlement brought about by filling construction,varying degrees of land subsidence and engineering failures have a demonstrated relationship to groundwater level fluctuation induced by land creation *** this work,we adopted a typical large-scale land creation project,Yan’an New City in Shaanxi province,West China,as our study *** to conducting the main experiment,preliminary field investigation and groundwater level monitoring were conducted to determine the groundwater fluctuation trend induced by land creation *** a blind drainage system was implemented,the depth aspect of groundwater level changes after large-scale land creation still needed to be *** study the degree of impact and the settlement mechanism induced by the rising groundwater level,we conducted a Water Immersion Test(WIT)in a typical land creation site for 107 *** rising groundwater level was simulated by injecting water from the bottom of the filling *** the WIT,the soil water content,surface subsidence,and internal settlement of soil at different depths were *** subsidence development could be categorized into four stages during the water level *** second stage,which is defined as the point when the groundwater level rises to 10 m,marked the critical point in the ***,it was ascertained that the local settlement in regions that were originally composed of steep slopes is larger than that in originally flat *** addition,ground cracks and sinkholes in the study area were inspected;and it was determined that they would become new channels that would accelerate water infiltration and exacerbate the *** on the results from our field investigation and testing,several suggestions are proposed for land creation projects to mitigate issues associated with construc

关键词： Water immersion test Land creation engineering Loess plateau Groundwater Subsidence

Human hepatocytes loaded in 3D bioprinting generate mini-liver

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Hepatobiliary & Pancreatic Diseases International 2016年第5期15卷 512-518页

作者： Cheng Zhong Hai-Yang Xie lin zhou Xiao Xu Shu-Sen Zheng Key Laboratory of Combined Multi-organ Transplantation Ministry of Public HealthFirst Affiliated HospitalZhejiang University School of Medicine

BACKGROUND: Because of an increasing discrepancy be-tween the number of potential liver graft recipients and the number of organs available, scientists are trying to create artiifcial liver to mimic normal liver function and therefore, to support the patient’s liver when in dysfunction. 3D printing technique meets this purpose. The present study was to test the feasibility of 3D hydrogel scaffolds for liver engineering. METHODS: We fabricated 3D hydrogel scaffolds with a bioprinter. The biocompatibility of 3D hydrogel scaffolds was tested. Sixty nude mice were randomly divided into four groups, with 15 mice in each group: control, hydrogel, hydro-gel with L02 (cell line HL-7702), and hydrogel with hepatocyte growth factor (HGF). Cells were cultured and deposited in scaffolds which were subsequently engrafted into livers after partial hepatectomy and radiation-induced liver damage (RILD). The engrafted tissues were examined after two weeks. The levels of alanine aminotransferase (ALT), aspartate amino-transferase (AST), albumin, total bilirubin, CYP1A2, CYP2C9, glutathione S-transferase (a-GST), and UDP-glucuronosyl transferase (UGT-2) were compared among the groups. He-matoxylin-eosin (HE) staining and immunohistochemistry of cKit and cytokeratin 18 (CK18) of engrafted tissues were evalu-ated. The survival time of the mice was also compared among the four groups. RESULTS: 3D hydrogel scaffolds did not impact the viability of cells. The levels of ALT, AST, albumin, total bilirubin, CY-P1A2, CYP2C9, a-GST and UGT-2 were signiifcantly improved in mice engrafted with 3D scaffold loaded with L02 compared with those in control and scaffold only (P CONCLUSION: 3D scaffold has the potential of recreating live

关键词： 3D printing hepatocyte liver tissue engineering

A simple method for determining water content in organic solvents based on cobalt(Ⅱ) complexes

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Chinese Chemical Letters 2011年第2期22卷 189-192页

作者： lin zhou Xiao Hua Liu Hai Xin Bai Hong Juan Wang College of Plant Protection Henan Agricultural UniversityZhengzhou 450002China College of Sciences Henan Agricultural UniversityZhengzhou 450002China

A method to determine water content in organic solvents was developed based on the color change of cobalt（Ⅱ） nitrate in different *** color-change mechanism and optimal conditions for determining the water content were *** results showed that there was a good linear relationships between the absorbance of cobalt（Ⅱ） complexes in organic solvents and water contents withγin 0.9989～*** method has the advantages of low cost,good reproducibility,good sensitivity,simple in operation,fast in detection,friendly to the environment and no limitation on linear range for determining water *** was used to determine water in samples with a satisfactory recovery in 97.81%～101.24%.

关键词： Determination Water content Cobalt(Ⅱ) nitrate Organic solvent

Sensitivity function analysis of gravitational wave detection with single-laser and large-momentum-transfer atomic sensors

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Research in Astronomy and Astrophysics 2015年第3期15卷 333-347页

作者： Biao Tang Bao-Cheng Zhang lin zhou Jin Wang Ming-Sheng Zhan State Key Laboratory of Magnetic Resonances and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences University of Chinese Academy of Sciences

Recently, a configuration using atomic interferometers （AIs） had been sug- gested for the detection of gravitational waves. A new AI with some additional laser pulses for implementing large momentum transfer was also put forward, in order to reduce the effect of shot noise and laser frequency noise. We use a sensitivity function to analyze all possible configurations of the new AI and to distinguish how many mo- menta are transferred in a specific configuration. By analyzing the new configuration, we further explore a detection scheme for gravitational waves, in particular, that ame- liorates laser frequency noise. We find that the amelioration occurs in such a scheme, but novelly, in some cases, the frequency noise can be canceled completely by using a proper data processing method.

关键词： gravitational wave detection -- atomic interferometer-- laser frequencynoise

Iron-Catalyzed Alkenylzincation of Internal Alkynes

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Chinese Journal of Chemistry 2023年第24期41卷 3547-3552页

作者： Wei-Na Wang Qiang Huang Ye Jin Qi-lin zhou Shou-Fei Zhu Frontiers Science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic ChemistryCollege of ChemistryNankai UniversityTianjin300071 China

The alkenylzincation of internal alkynes is an effective method for the synthesis of multi-substituted conjugated dienes;however,the current catalytic systems for this reaction are limited in terms of substrate scope and selectivity control,which restricts its practical ***,we report the first iron-catalyzed alkenylzincation of internal alkynes,which features mild conditions,simple operation,broad substrate scope (including aryl/alkyl,diaryl,and dialkyl acetylenes),excellent functional group tolerance (tolerating highly active functional groups such as ester,methylthio,amide,sulfonyl,cyano,etc.),and high activity (with a turnover number of up to 11500,the highest record for carbometallation reactions).Notably,the catalytic system described in this article also realized the highly selective vinylzincation of unfunctionalized internal alkynes as well as the alkenylzincation of unsymmetrical diarylacetylenes and dialkyl acetylenes,which have not been achieved with other catalytic systems reported in the *** current study provides a highly selective access to synthetically important multi-substituted conjugated dienes.

关键词： Iron catalysis Internal alkynes Alkenylzincation Conjugated dienes

Forthrightly monitoring ferroptosis induced by endoplasmic reticulum stresses through fluorescence lifetime imaging of microviscosity increases with a specific rotor

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Chinese Chemical Letters 2022年第5期33卷 2537-2540页

作者： Chuanhao Liu lin zhou Lijuan Xie Ying Zheng Huizi Man Yi Xiao Engineering Research Center of Molecular Medicine of Ministry of Education Key Laboratory of Fujian Molecular MedicineSchool of MedicineHuaqiao UniversityQuanzhou 362021China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China

To test the hypothesis that the microviscosity changes of Endoplasmic Reticulum(ER)can be a useful indicator of ferroptosis promoted by ER Stresses(ERS),a new ER targeting viscosity rotor,L-Vis-1 was developed and applied in the quantitation of viscosity by FLIM imaging in live *** FLIM imag-ing exhibited an excellent resolution almost as good as the corresponding confocal imaging,more sig-nificantly,during ferroptosis processes promoted by different types of ERS,the viscosity increases were clearly monitored by FLIM of L-Vis-1 within ER,which has not been demonstrated before.

关键词： Ferroptosis Viscosity FLIM ERS Rotor