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A new integration algorithm for finite deformation of thermo-elasto-viscoplastic single crystals

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Acta Mechanica Sinica 2013年第5期29卷 709-717页

作者： Dan Zhao Yi-Guo Zhu Ping Hu wan-xi Zhang State Key Laboratory of Structural Analysis for Industrial Equipment Faculty of Vehicle Engineering and MechanicsDalian University of Technology

An algorithm for integrating the constitutive equations in thermal framework is presented, in which the plastic deformation gradient is chosen as the integration variable. Compared with the classic algorithm, a key feature of this new approach is that it can describe the finite deformation of crystals under thermal conditions. The obtained plastic deformation gradient contains not only plastic defor- mation but also thermal effects. The governing equation for the plastic deformation gradient is obtained based on ther- mal multiplicative decomposition of the total deformation gradient. An implicit method is used to integrate this evo- lution equation to ensure stability. Single crystal 1 100 aluminum is investigated to demonstrate practical applications of the model. The effects of anisotropic properties, time step, strain rate and temperature are calculated using this integration model.

关键词： Integration algorithm - Thermal effect Anisotropic elasticity Single crystal Finite deformation

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高架桥车辆行驶引起的环境振动研究

山西建筑 2025年第2期51卷 154-157页

作者：万曦代剑英吴芳信息产业电子第十一设计研究院科技工程股份有限公司陕西西安710000 中国建筑西北设计研究院有限公司陕西西安710000 华南农业大学广东广州510000

随着高科技产业的快速发展,对精密工程结构中产品质量的要求日益提高,其中微振动控制成为关键因素。针对西安某微电子厂房建设项目,考虑到周边高速公路高架桥对拟建场地可能产生的微振动影响,进行了详细的现场测试与分析。通过布置测点... 详细信息

随着高科技产业的快速发展,对精密工程结构中产品质量的要求日益提高,其中微振动控制成为关键因素。针对西安某微电子厂房建设项目,考虑到周边高速公路高架桥对拟建场地可能产生的微振动影响,进行了详细的现场测试与分析。通过布置测点,采用高灵敏度振动传感器和数据采集系统,记录了南北、东西和垂直方向的振动速度。测试结果表明,高速公路高架桥的微振动水平处于VC-D—VC-C之间,可为芯片厂房的选址和隔振设计提供科学依据,对类似精密工程结构的防微振设计具有参考意义。

关键词：隔振设计微振动频域分析数据采集

Protein profile of human hepatocarcinoma cell line SMMC-7721:Identification and functional analysis

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World Journal of Gastroenterology 2007年第18期13卷 2608-2614页

作者： Yi Feng Zhong-Min Tian Ming-xi wan Zhao-Bin Zheng The Key Laboratory of Biomedical Information Engineering-of Ministry of Education Department of Biomedical EngineeringSchool of Life Science and Technology Xi'an Jiaotong UniversityXi'an 710049 Shaanxi Province China

AIM： TO investigate the protein profile of human hepatocarcinoma cell line SMMC-7721, to analyze the specific functions of abundant expressed proteins in the processes of hepatocarcinoma genesis, growth and metastasis, to identify the hepatocarcinoma-specific biomarkers for the early prediction in diagnosis, and to explore the new drug targets for liver cancer therapy. METHODS： Total proteins from human hepatocarcinoma cell line SMMC-7721 were separated by two-dimensional electrophoresis （2DE）. The silver-stained gel was analyzed by 2DE software Image Master 2D Elite. Interesting protein spots were identified by peptide mass fingerprinting based on matrix-assisted laser desorption/ ionization time-of-flight mass spectrometry （MALDI-TOF-MS） and database searching. RESULTS： We obtained protein profile of human hepatocarcinoma cell line SMMC-7721. Among the twenty-one successfully identified proteins, mitofilin, endoplasmic reticulum protein ERp29, ubiquinol-cytochrome C reductase complex core protein I, peroxisomal enoyl CoA hydratase, peroxiredoxin-4 and probable 3-oxoacid CoA transferase 1 precursor were the six novel proteins identified in human hepatocarcinoma cells or tissues. Specific functions of the identified heat-shock proteins were analyzed in detail, and the results suggested that these proteins might promote tumorigenesis via inhibiting cell death induced by several cancer-related stresses or via inhibiting apoptosis at multiple points in the apoptotic signal pathway. Other identified chaperones and cancer-related proteins were also analyzed.CONCLUSION： Based on the protein profile of SMMC-7721 cells, functional analysis suggests that the identified chaperones and cancer-related proteins have their own pathways to contribute to the tumorigenesis, tumor growth and metastasis of liver cancer. Furthermore, proteomic analysis is indicated to be feasible in the cancer study.

关键词： Human hepatocarcinoma cell line SMMC-7721 Protein identification Functional analysis Heat-shockprotein Tumorigenesis

Low intensity ultrasound-induced apoptosis in human gastric carcinoma cells

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World Journal of Gastroenterology 2008年第31期14卷 4873-4879页

作者： Yi Feng Zhong-Min Tian Ming-xi wan Zhao-Bin Zheng Key Laboratory of Biomedical Information Engineering of Ministry of Education Department of Biomedical Engineering School of Life Science and Technology Xi'an Jiaotong University Xi'an 710049 Shaanxi Province China

AIM： To investigate the low intensity ultrasound （US）- induced apoptosis in human gastric carcinoma cells and its potential mechanism and to suggest a new therapeutic approach to gastric carcinoma. METHODS： Human SGC-7901 gastric carcinoma cells were cultured in vitro and irradiated by low intensity US for 10 min at different intensities with different incubation times after irradiation. Morphologic changes were examined under microscope with trypan blue staining and then the percentage of early apoptotic cells was detected by flow cytometry （FCM） with double staining of fiuorescein isothiocyanate （FITC）- Annexin V/propidium iodide （PI）. Two-dimensional electrophoresis （2DE） was used to get the protein profile and some proteins differently expressed after US irradiation were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. Functional analysis was performed to investigate the mechanism of US-induced cell apoptosis. RESULTS： The percentage of apoptotic cells increased about 10% after US irradiation （12.0 W/cm^2, 12 h culture）, The percentage of early apoptosis and secondary necrosis in the US-irradiated cells increased with the increased US intensity. Moreover, apoptotic cells increased with the increased culture time after US irradiation and reached its maximum at about 12 *** new proteins appeared after US irradiation and were up or down regulated more than 2 times. Some heat shock proteins （HSPs） were found to be associated with the signal process simulating the apoptosis of cells. CONCLUSION： Low intensity US could induce apoptosis in human gastric carcinoma cells. US-induced apoptosis is related to US intensity/culture time. US-induced apoptosis may be caspases-dependent and endoplasmic reticulum （ER） stress-triggered apoptosis may also contribute to it. Proteomic experimental system is useful in finding the protein alteration in carcinoma cells after US irradiation, helping to develop a new cancer

关键词： SGC-7901 human gastric carcinoma cells Low intensity ultrasound Apoptosis Caspasesdependent Proteomics

Review:Actin-based dynamics during spermatogenesis and its significance

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第7期8卷 498-506页

作者： xiAO xiang YANG wan-xi The Sperm Laboratory Institute of Cell Biology and Genetics School of Life Sciences Zhejiang University Hangzhou 310058 China

Actin can be found in all kinds of eukaryotic cells, maintaining their shapes and motilities, while its dynamics in sperm cells is understood less than their nonmuscle somatic cell counterparts. Spermatogenesis is a complicated process, resulting in the production of mature sperm from primordial germ cell. Significant structural and biochemical changes take place in the seminif-erous epithelium of the adult testis during spermatogenesis. It was proved that all mammalian sperm contain actin, and that F-actin may play an important role during spermatogenesis, especially in nuclear shaping. Recently a new model for sperm head elonga-tion based on the acrosome-acroplaxome-manchette complex has been proposed. In Drosophila, F-actin assembly is supposed to be very crucial during individualization. In this mini-review, we provide an overview of the structure, function, and regulation characteristics of actin cytoskeleton, and a summary of the current status of research of actin-based structure and movement is also provided, with emphasis on the role of actins in sperm head shaping during spermiogenesis and the cell junction dynamics in the testis. Research of the Sertoli ectoplasmic specialization is in the spotlight, which is a testis-specific actin-based junction very important for the movement of germ cells across the epithelium. Study of the molecular architecture and the regulating mechanism of the Sertoli ectoplasmic specialization has become an intriguing field. All this may lead to a new strategy for male infertility and, at the same time, a novel idea may result in devising much safer contraception with high efficiency. It is hoped that the advances listed in this review would give developmental and morphological researchers a favorable investigating outline and could help to enlarge the view of new strategies and models for actin dynamics during spermatogenesis.

关键词： Testis Actin Spermatogenesis Nuclear shaping Sertoli cell

NONISOTHERMAL CRYSTALLIZATION AND MORPHOLOGY OF POLY(BUTYLENE SUCCINATE)/LAYERED DOUBLE HYDROxiDE NANOCOMPOSITES

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Chinese Journal of Polymer Science 2013年第1期31卷 187-200页

作者： Mei-qiu Zhan Guang-yi Chen 魏志勇 Yu-mei Shi wan-xi Zhang School of Material Science and Engineering Jilin University School of Automotive Engineering Dalian University of Technology

Biodegradable poly（butylene succinate）（PBS） and layered double hydroxide （LDH） nanocomposites were prepared via melt blending in a twin-screw extruder. The morphology and dispersion of LDH nanoparticles within PBS matrix were characterized by transmission electron microscopy （TEM）, which showed that LDH nanoparticles were found to be well distributed at the nanometer level. The nonisothermal crystallization behavior of nanocomposites was extensively studied using differential scanning calorimetry （DSC） technique at various cooling rates. The crystallization rate of PBS was accelerated by the addition of LDH due to its heterogeneous nucleation effect; however, the crystallization mechanism and crystal structure of PBS remained almost unchanged. In kinetics analysis of nonisothermal crystallization, the Ozawa approach failed to describe the crystallization behavior of PBS/LDH nanocomposites, whereas both the modified Avrami model and the Mo method well represented the crystallization behavior of nanocomposites. The effective activation energy was estimated as a function of the relative degree of crystallinity using the isoeonversional analysis. The subsequent melting behavior of PBS and PBS/LDH nanocomposites was observed to be dependent on the cooling rate. The POM showed that the small and less perfect crystals were formed in nanocomposites.

关键词： Poly(butylene succinate) Layered double hydroxide Nonisothermal crystallization.

Es-SOX8 regulates the morphological changes of the sperm nucleus of Eriocheir sinensis by activating Es-BMP2 transcription

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BIOCELL 2022年第11期46卷 2399-2413页

作者： KE JIA FU-QING TAN SHUANG-LI HAO wan-xi YANG The Sperm Laboratory College of Life SciencesZhejiang UniversityHangzhou310058China The First Affiliated Hospital College of MedicineZhejiang UniversityHangzhou310003China

The SRY-related high mobility group(HMG)box(SOX)transcription factors participate in many physiological processes of animal growth,development,and reproduction and are related to spermatogenesis in many ***,the relationship between SOX and spermatogenesis in Eriocheir sinensis is rarely ***,we studied the role of Es-SOX8 in the spermatogenesis of *** and its possible regulation *** results demonstrated Es-SOX8 signal in both cytoplasm and nucleus of spermatogonia,spermatocytes as well as spermatids,but not in mature *** and eosin staining showed a significant increase in the number of spermatozoa with abnormal nuclear morphology in vivo,described as prominent edges and corners,after the knockdown of Es-SOX8 through RNA *** indicated a possible role of Es-SOX8 in the nuclear deformation process in the spermatogenesis of *** of the mRNA levels of Es-bone morphogenetic protein 2(BMP2)in the Es-Sox8 knocked-down testis tissue revealed significantly decreased transcription of *** immunoprecipitation results showed the binding of Es-SOX8 protein to the promoter region of ***,Es-SOX8 can directly regulate the transcription of Es-BMP2 by activating the promoter of Es-BMP2 and thus affects the sperm nucleus deformation of ***.

关键词： SOX Transcription factor Spermatogenesis BMP2

BLOOD PRESSURE CHANGES OF ELDERLY HYPERTENSIVE PATIENTS DURING DENTAL EXTRACTION UNDER SEDATION WITH CONTINUOUS INTRAVENOUS INFUSION OF MIDAZOLAM

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Chinese Medical Sciences Journal 2007年第2期22卷 132-135页

作者： Ji-zhi Zhao Kuo wan Quan Jing xi Chen Department of Stomatology Peking Union Medical College Hospital Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100730

Objective To evaluate the changes in blood pressure (BP) of elderly hypertensive patients having dental extraction under sedation with continuous intravenous infusion of midazolam. Methods One hundred elderly hypertensive patients undergoing dental extraction were recruited for this single-blind, randomized, controlled study. Patients in intervention group (n=50) were given midazolam dissolved in glucose solution and patients in control group (n=50) were given glucose solution only with communication technique. Systolic BP (SBP) and diastolic BP (DBP) were recorded in five time points. Results Under basal conditions, intervention group did not show significant difference in BP compared with control group. Before sedation, mean values of SBP and DBP (especially SBP) significantly increased compared with basal conditions in both groups (P<0.05). During dental extraction sessions, mean values of BP in intervention group significantly decreased than control group (P<0.05), but coefficient of variation did show significant difference in both groups. Conclusion Continuous intravenous infusion of midazolam has been proved to be very successful in controlling BP of elderly patients having dental extraction.

关键词： midazolam intravenous infusion hypertension dental extraction aged

Optical Properties of Fullerenated Poly(epoxy propyl carbazole)

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Chinese Chemical Letters 1998年第9期9卷 835-837页

作者： Tao GU wan xi CHEN Zhu De XU (Department of Chemistry, Zhejiang University, Hangzhou 310027) Department of Chemistry Zhejiang University Hangzhou 310027 China

The optical properties of the fullerenated poly(epoxy propyl carbazole) (PEPC) have been investigated. Compared with pure PEPC, fullerenated PEPC has the same structure in the UV region of the absorption spectrum, and extends the active range to a longer wavelength. The apparent quenching of PEPC fluorescence was observed in the fullerenated polymer and it can be attributed to intramolecular excited state energy transfer.

关键词： fullerene (fullerenated) PEPC (poly(epoxy propyl carbazole)) optical properties