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Vibration analysis of a simply supported beam under moving mass based on moving finite element method

Zhuchao YE, Huaihai CHEN,

《机械工程前沿（英文）》 2009年 第4卷 第4期   页码 397-400 doi: 10.1007/s11465-009-0044-7

摘要： In this paper, a moving finite element (MFE) method is proposed to perform the dynamic analysis of a simply supported beam for a moving mass (MM). The MFE method treats the moving mass as a moving part of the entire system, so that the transverse inertial effects caused by the moving mass may easily be taken into account. The solution to the beam’s dynamic behaviors including its displacement is obtained via a Newmark-β method; the effects of the velocity and weight of the MM on the beam’s dynamic behaviors are further discussed. The numerical examples show that the inertial effects of the MM significantly affect the transverse responses of the simply supported beam.

关键词： simply supported beam     moving mass (MM)     transverse vibration     moving finite element (MFE)    

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Adenovirus-mediated tissue inhibitor of metalloproteinase-3 gene transfection inhibits rabbit intervertebral disc degeneration in vivo

Xudong YU MM, Zengwu SHAO MD, Liming XIONG MD, Weiwei XU MM, Hezhong WANG MM, Huifa XU MM,

《医学前沿（英文）》 2009年 第3卷 第4期   页码 415-420 doi: 10.1007/s11684-009-0072-z

摘要： The aim of this study was to investigate the inhibitory effects of recombinant adenovirus vector carrying tissue inhibitor of metalloproteinase-3 (RAdTIMP-3) against degeneration of rabbit intervertebral disc. Thirty Japanese white rabbits of 4 months old were randomly divided into 5 groups. Mild or moderate rabbit lumbar disc degeneration model was constructed with the controllable axial loading device by imposing 98N pressure at the discs for 2 weeks. Various doses of virus were injected into the degenerated discs as follows: 20μL of normal saline in group 1; 20μL of RAd66 (an empty adenovirus vector, 1.0×10OPU/mL) in group 2; and 20, 10, and 5μL of RAdTIMP-3 (1.0×10OPU/mL) in groups 3, 4, and 5, respectively. Two weeks after the injection, the discs were collected for investigations, including assessment of degeneration degrees according to the Thompson’s grading system, reverse-transcription polymerase chain reaction (RT-PCR) assay for TIMP-3 gene, Safranin O-Fast green staining, and immunohistochemical staining for TIMP-3 and type II collagen. According to Thompson’s criteria, the degeneration of groups 3, 4, and 5, especially group 3, was alleviated as compared with groups 1 and 2. RT-PCR revealed that the expression of TIMP-3 in groups 3, 4, and 5, especially in group 3, was significantly enhanced as compared with group 1 (<0.01). Both Safranin O-Fast green staining and type II collagen staining demonstrated better reserved integrity of disc matrix in groups 3, 4, and 5 than in groups 1 and 2. TIMP-3 staining exhibited an obvious increase of positive-staining rate in groups 3, 4, and 5 as compared with group 1. The positive-staining rate in group 3 (79.42%±1.35%) was about 3times that of group 1 (25.47%±5.46%, <0.01). RAdTIMP-3 can effectively protect the matrix of rabbit intervertebral disc against overloading-induced degeneration in a dose-dependent manner, resulting in the alleviation of disc degeneration.

关键词： tissue inhibitor of metalloproteinase-3     intervertebral disc     rabbit     gene therapy    

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Role of stair-climbing test in predicting postoperative cardiopulmonary complications in elderly patients with biliary diseases

Pei-Tu REN BM, Bao-Chun LU MM, Zhi-Liang CHEN MM, Hong FU MM,

《医学前沿（英文）》 2010年 第4卷 第1期   页码 77-81 doi: 10.1007/s11684-010-0005-x

摘要： One hundred and twenty-six patients above 80 years old with biliary diseases undergoing operations in Shaoxing People’s Hospital from Jan. 2002 to Jan. 2007 were analyzed retrospectively. All patients performed a preoperative stair-climbing test, and the risks for cardiopulmonary €complications were evaluated with pair-matching and linear correlations analysis between stair-climbing height (h) and left ventricular ejective factor (EF), forced vital capacity (FVC) and forced expiratory volume in one second (FEV). There was a significant difference in the incidence of cardiopulmonary complications among different stair-climbing heights. Stair-climbing heights were positively related with EF, FVC and FEV. This suggests that the stair-climbing test is an effective and simple method for predicting cardiopulmonary complications in elderly patients with biliary diseases.

关键词： biliary disease     cardiopulmonary complication     stair-climbing test    

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Dynamic prediction of moving trajectory in pipe jacking: GRU-based deep learning framework

《结构与土木工程前沿（英文）》   页码 994-1010 doi: 10.1007/s11709-023-0942-5

摘要： The moving trajectory of the pipe-jacking machine (PJM), which primarily determines the end quality of jacked tunnels, must be controlled strictly during the entire jacking process. Developing prediction models to support drivers in performing rectifications in advance can effectively avoid considerable trajectory deviations from the designed jacking axis. Hence, a gated recurrent unit (GRU)-based deep learning framework is proposed herein to dynamically predict the moving trajectory of the PJM. In this framework, operational data are first extracted from a data acquisition system; subsequently, they are preprocessed and used to establish GRU-based multivariate multistep-ahead direct prediction models. To verify the performance of the proposed framework, a case study of a large pipe-jacking project in Shanghai and comparisons with other conventional models (i.e., long short-term memory (LSTM) network and recurrent neural network (RNN)) are conducted. In addition, the effects of the activation function and input time-step length on the prediction performance of the proposed framework are investigated and discussed. The results show that the proposed framework can dynamically and precisely predict the PJM moving trajectory during the pipe-jacking process, with a minimum mean absolute error and root mean squared error (RMSE) of 0.1904 and 0.5011 mm, respectively. The RMSE of the GRU-based models is lower than those of the LSTM- and RNN-based models by 21.46% and 46.40% at the maximum, respectively. The proposed framework is expected to provide an effective decision support for moving trajectory control and serve as a foundation for the application of deep learning in the automatic control of pipe jacking.

关键词： dynamic prediction     moving trajectory     pipe jacking     GRU     deep learning    

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Effect of lanthanum chloride on growth of breast cancer cells and regulation of transcription

Xue LI MM , Ping HE MM , Jie XIA MM , Shiwei SONG BS , Jinhai LU BM , Yunde LIU MM ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 336-340 doi: 10.1007/s11684-009-0053-2

摘要： Lanthanum salt is a prescription drug, but its underlying functions and mechanisms are not fully understood currently. To explore the potential therapeutic value of , cytotoxicity test was applied to investigate its effects on cell proliferation. Furthermore, we observed its influence on pro-oncogene by reverse transcription polymerase chain reaction (RT-PCR). In MCF-7 cell line, repressed cell proliferation at high concentration but had no significant inhibition effect on cell growth at low concentration. However, we observed that repressed transcription at a low concentration. This may suggest that is a potent drug to inhibit the high expression of in carcinoma cells and play a clue for inhibiting the growth and invasion of tumor.

关键词： proliferation     c-met     invasion     lanthanum chloride    

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Design and analysis of the gripper mechanism based on generalized parallel mechanisms with configurable moving

《机械工程前沿（英文）》 2021年 第16卷 第4期   页码 765-781 doi: 10.1007/s11465-021-0655-1

摘要： Generalized parallel mechanisms with a configurable moving platform have become popular in the research field of parallel mechanism. This type of gripper mechanism can be applied to grasp large or heavy objects in different environments that are dangerous and complex for humans. This study proposes a family of novel (5 + 1) degrees of freedom (three translations and two rotations plus an additional grasping motion) gripper mechanisms based on the generalized parallel mechanisms with a configurable moving platform. First, the configurable moving platform, which is a closed loop, is designed for grasping manipulation. The hybrid topological arrangement is determined to improve the stiffness of the manipulator and realize high load-to-weight ratios. A sufficient rule based on Lie group theory is proposed to synthesize the mechanism. The hybrid limb structure is also enumerated. A family of novel gripper mechanisms can be assembled through the hybrid limbs by satisfying the rule. Two examples of the gripper mechanisms with and without parallelogram pairs are shown in this study. A kinematic analysis of the example mechanism is presented. The workspace shows that the mechanism possesses high rotational capability. In addition, a stiffness analysis is performed.

关键词： generalized parallel mechanism     configurable moving platform     gripper mechanism     type synthesis     kinematic analysis    

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Multi-harmonic forced vibration and resonance of simple beams to moving vehicles

《结构与土木工程前沿（英文）》   页码 981-993 doi: 10.1007/s11709-023-0979-5

摘要： This study modeled the moving-vehicle-induced forcing excitation on a single-span prismatic bridge as a multiple frequency-multiplication harmonic load on the modal coordinates of a linear elastic simple Euler–Bernoulli beam, and investigated the forced modal oscillation and resonance behavior of this type of dynamic system. The forced modal responses consist of multiple frequency-multiplication steady-state harmonics and one damped mono-frequency complementary harmonic. The analysis revealed that a moving load induces high-harmonic forced resonance amplification when the moving speed is low. To verify the occurrence of high-harmonic forced resonance, numerical tests were conducted on single-span simple beams based on structural modeling using the finite element method (FEM) and a moving sprung-mass oscillator vehicle model. The forced resonance amplification characteristics of the fundamental mode for beam response estimation are presented with consideration to different end restraint conditions. The results reveal that the high-harmonic forced resonance may be significant for the investigated beams subjected to vehicle loads moving at specific low speeds. For the investigated single-span simple beams, the moving vehicle carriage heaving oscillation modulates the beam modal frequency, but does not induce notable variation of the modal oscillation harmonic structure for the cases that vehicle of small mass moves in low speed.

关键词： forced vibration     linear Euler beam     moving load     harmonic structure     frequency modulation     end restraints    

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Effect of pirfenidone on renal tubulointerstitial fibrosis

Dixin LI MM , Hongbing ZENG MD , Chunyang JI MM ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 316-322 doi: 10.1007/s11684-009-0045-2

摘要： Renal tubulointerstitial fibrosis (TIF) is the common end stage of various chronic renal diseases, and pirfenidone (PFD) is a novel, broad-spectrum anti-fibrotic compound but little is known about its effect and mechanism of action on renal TIF. In this work, we employed a unilateral ureteral obstruction (UUO) rat model to investigate the apoptosis of renal tubular epithelial cells (RTC) after PFD treatment. Thirty-five Sprague Dawley (SD) rats were randomized into three groups: sham-operated group (=7), UUO group (=14) and PFD group (=14). All rats were sacrificed at day 7 or 14 after operation. Renal histology was studied by using periodic acid schiff reagent (PAS) and Masson trichromic stain (MASSON); apoptosis was detected by terminal deoxynucleotide transferase-mediated dUTP-biotin nick end-labeling (TUNEL); tubular caspase-3 expression was assessed by immunohistochemistry. The content of malondialdehyde (MDA) and total activity of superoxide dismutase (T-SOD) in the renal cortex was determined by chemical colorimetry method. TIF, apoptosis of RTC, tubular expression of caspase-3 and the content of MDA were increased in the UUO group compared with those in the sham-operated group, and were ameliorated significantly by PFD treatment (<0.05). The activity of SOD was decreased in the UUO group, but was improved by PFD treatment (<0.05). Our results showed that PFD could ameliorate TIF in the UUO group, and the possible mechanism was by reducing the apoptosis of RTC, which involved oxidative stress and caspase-3.

关键词： pirfenidone     apoptosis     caspase 3     oxidative stress    

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Effects of phosphatidylinositol 3-kinase inhibitor on human cervical carcinoma cells

Yuan ZHANG MD , Xiaoyan ZHANG MM , Yanhui LI MM , Xuan DU MM , Zehua WANG MD, PhD , Hongbo WANG MD ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 341-346 doi: 10.1007/s11684-009-0067-9

摘要： Phosphatidylinositol 3-kinase (PI3K) is a crucial cell survival pathway implicated in tumorigenesis because of its role in stimulating cell proliferation and suppressing apoptosis. This study was to investigate the regulation of proliferation and apoptosis by LY294002, an inhibitor of PI3K in cervical cancer cells and the expression of FLICE-like inhibitory protein (c-FLIP) . Human cervical cancer HeLa cells were used in this experiment and cultured. The cultured cells were treated with LY294002 at different concentrations (10, 25, 50 and 100µmol/L) for 6, 12, 24, and 48h before harvesting for evaluation. Cell viability was measured by 3-(4,5)-dimethylthiazol(-2-y1)-3,5-di-phenyltetrazoliumbromide (MTT) assay. Apoptosis was analyzed by flow cytometry. The expression of c-FLIP was detected by Western blot. Cell viability was inhibited by LY294002 significantly (<0.05). Flow cytometry analysis revealed that cell apoptosis was significantly increased in the presence of LY294002 as compared with the control group. Although the expression of c-FLIP was increased in a short time, the expression of c-FLIP was markedly suppressed after the treatment of LY294002 for 48h. These results suggested that the PI3K/Akt signal pathway might be involved in the regulation of cell apoptosis in cervical cancer cells. Moreover, the regulation of c-FLIP expression through PI3K/Akt signal pathway in cervical cancer cells was observed .

关键词： human cervical cancer cells     apoptosis     phosphatidylinositol 3-kinase (PI3K)/Akt     FLICE-like inhibitory protein    

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Correlation between viral load and liver cirrhosis in chronic hepatitis B patients

Lili LIU MM , Jiyao WANG MD , Weimin SHE MM ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 271-276 doi: 10.1007/s11684-009-0054-1

摘要： The aim of this paper is to investigate the relationship between hepatitis B virus (HBV) DNA levels during the course and the progression to cirrhosis with chronic hepatitis B. A total of 239 chronic hepatitis B patients confirmed by liver biopsy between 2001 and 2007 were followed up for a median of 28 months. Compared with the patients without cirrhosis, the patients progressed to cirrhosis were older and with higher HBV-DNA levels at end point. However, there was no significant difference in cirrhosis progression between different HBV-DNA groups at baseline ( = 0.531). Kaplan-Meier analysis showed higher HBV-DNA level at endpoint had increasing risk of cirrhosis ( = 0.019). The results of Cox model indicated that HBV-DNA levels at endpoint, stage of fibrosis, negative hepatitis B e antigen, and γ-glutamyl transpeptidase at baseline were independent risk factors of cirrhosis. The relative risk ratios were 1.898, 1.918, 8.976, and 1.006, respectively. Progression to cirrhosis in chronic hepatitis B patients is correlated with HBV-DNA levels during follow-up.

关键词： hepatitis B     chronic     viral load     liver cirrhosis    

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The role of CDK1 siRNA interference in cell cycle and cell apoptosis

Hui XIAO PhD, Ming TIAN MM, Junna GE MM, Xin Wei MD, Zhaoming LI MM, Xiaolan LI MS, Deding TAO PhD, Junbo

《医学前沿（英文）》 2009年 第3卷 第4期   页码 384-389 doi: 10.1007/s11684-009-0070-1

摘要： In the present report, cyclin-dependent kinase1 (CDK1) siRNA was transfected into cells to silence the CDK1 gene expression and study its role in the cell cycle and cell apoptosis. The siRNA targeting CDK1 gene was chemically synthesized and transfected into Hela cells by lipofectamine 2000. The expression levels of CDK1 gene and protein were examined by real-time quantitative polymerase chain reaction (PCR) and Western blot, respectively. The cell cycle was analyzed by using DNA content analysis by flow cytometry. Cell apoptosis was detected by the Annexin V/PI method. The morphological changes of transfected cells were examined under the microscopy by Wright-Giemsa stain. CDK1 gene was successfully silenced by its siRNA, and the CDK1 protein expression level was decreased significantly, especially from 48thh to 60thh after transfection. The DNA content analysis showed that transfection of CDK1 siRNA led to cells accumulating in G/M phase. There was no significant difference in the apoptotic rate between transfected cells and the control cells after transfection of CDK1 siRNA for 48 or 60h. More double nucleus or multinucleus cells could be seen under the microscopy among the transfected cells. The decreased CDK1 expression by siRNA silencing gave rise to cell cycle arrest in G/M phase but did not induce apoptosis.

关键词： cyclin-dependent kinase1     siRNA interference     cell cycle     apoptosis    

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The next step of community health construction: Training general practitioners and implementing health management

Kan ZHANG MM, Wei DONG MM, Ying-Yao CHEN MD,

《医学前沿（英文）》 2010年 第4卷 第2期   页码 134-138 doi: 10.1007/s11684-010-0041-6

摘要： This article discusses the concept of health management and stresses that community health management should be the starting point of community health service, necessitating a paradigm shift from observing the treatment-oriented medical model to observing the prevention-and-health management-based medical model. Community health construction has entered a new phase, one which highlights the need to train general practitioners in practice-based life cycle health management. In addition, general practitioners should assume the mission of implementing community health management.

关键词： community health     general practitioners     health management    

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灵活可变的运动图像的分割算法

赵彦玲,张之超,高振,张庆超

《中国工程科学》 2006年 第8卷 第5期   页码 84-87

摘要：

运动图像的分割在基于内容的视频编码及视频检索中占有重要的地位。利用运动图像帧中的时空域信息，提出了一种分割运动对象的方法。其最大的特点是灵活性，可以根据序列的实际情况来选择算法。实验证明分割效果较好并节省了处理时间。

关键词： 时空结合     运动区域     运动对象     形态梯度算子     灵活性    

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Effects of carrier-attached biofilm on oxygen transfer efficiency in a moving bed biofilm reactor

Yanling WEI,Xunfei YIN,Lu QI,Hongchen WANG,Yiwei GONG,Yaqian LUO

《环境科学与工程前沿（英文）》 2016年 第10卷 第3期   页码 569-577 doi: 10.1007/s11783-015-0822-x

摘要： Three laboratory-scale moving bed biofilm reactors (MBBR) with different carrier filling ratios ranging from 40% to 60% were used to study the effects of carrier-attached biofilm on oxygen transfer efficiency. In this study, we evaluated the performance of three MBBRs in degrading chemical oxygen demand and ammonia. The three reactors removed more than 95% of -N at an air flow-rate of 60 L·h . The standard oxygen transfer efficiency (αSOTE) of the three reactors was also investigated at air flow-rates ranging from 60 to 100 L·h . These results were compared to αSOTE of wastewater with a clean carrier (no biofilm attached). Results showed that under these process conditions, αSOTE decreased by approximately 70% as compared to αSOTE of wastewater at a different carrier-filling ratio. This indicated that the biofilm attached to the carrier had a negative effect on αSOTE. Mechanism analysis showed that the main inhibiting effects were related to biofilm flocculants and soluble microbial product (SMP). Biofilm flocs could decrease αSOTE by about 20%, and SMP could decrease αSOTE by 30%–50%.

关键词： carrier     biofilm     oxygen transfer efficiency     moving bed biofilm reactor    

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Preliminary results of gentamycin combined with sodium bicarbonate for prevention of irinotecan-induced diarrhea

Qi MEI MM, Zhe CAO MM, Hua XIONG MD, Yuan CHEN MD,

《医学前沿（英文）》 2009年 第3卷 第4期   页码 470-474 doi: 10.1007/s11684-009-0077-7

摘要： The aim of this paper was to observe the clinical effect of gentamycin combined with sodium bicarbonate for the prevention of irinotecan-induced diarrhea. A total of 98 patients with stage IV cancers were recruited and divided into a prevention group (52 patients) and a control group (46 patients). All patients received the chemotherapy including irinotecan. The prevention group received gentamycin and sodium bicarbonate before the use of irinotecan for 4 days; the control group did not receive any prevention. The use of gentamycin and sodium bicarbonate resulted in significantly higher stool pH ( < 0.001), while the incidence of diarrhea by irinotecan was reduced (prevention group 13.70% control group 34.83%; < 0.001). Gentamycin combined with sodium bicarbonate appears to be useful in preventing the diarrhea induced by irinotecan and reducing the dosage of loperamide and fluid replacement.

关键词： irinotecan     diarrhea     gentamycin     sodium bicarbonate     prevention    

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标题 作者 时间 类型 操作

Vibration analysis of a simply supported beam under moving mass based on moving finite element method

Zhuchao YE, Huaihai CHEN,

期刊论文

Adenovirus-mediated tissue inhibitor of metalloproteinase-3 gene transfection inhibits rabbit intervertebral disc degeneration in vivo

Xudong YU MM, Zengwu SHAO MD, Liming XIONG MD, Weiwei XU MM, Hezhong WANG MM, Huifa XU MM,

期刊论文

Role of stair-climbing test in predicting postoperative cardiopulmonary complications in elderly patients with biliary diseases

Pei-Tu REN BM, Bao-Chun LU MM, Zhi-Liang CHEN MM, Hong FU MM,

期刊论文

Dynamic prediction of moving trajectory in pipe jacking: GRU-based deep learning framework

期刊论文

Effect of lanthanum chloride on growth of breast cancer cells and regulation of transcription

Xue LI MM , Ping HE MM , Jie XIA MM , Shiwei SONG BS , Jinhai LU BM , Yunde LIU MM ,

期刊论文

Design and analysis of the gripper mechanism based on generalized parallel mechanisms with configurable moving

期刊论文

Multi-harmonic forced vibration and resonance of simple beams to moving vehicles

期刊论文

Effect of pirfenidone on renal tubulointerstitial fibrosis

Dixin LI MM , Hongbing ZENG MD , Chunyang JI MM ,

期刊论文

Effects of phosphatidylinositol 3-kinase inhibitor on human cervical carcinoma cells

Yuan ZHANG MD , Xiaoyan ZHANG MM , Yanhui LI MM , Xuan DU MM , Zehua WANG MD, PhD , Hongbo WANG MD ,

期刊论文

Correlation between viral load and liver cirrhosis in chronic hepatitis B patients

Lili LIU MM , Jiyao WANG MD , Weimin SHE MM ,

期刊论文

The role of CDK1 siRNA interference in cell cycle and cell apoptosis

Hui XIAO PhD, Ming TIAN MM, Junna GE MM, Xin Wei MD, Zhaoming LI MM, Xiaolan LI MS, Deding TAO PhD, Junbo

期刊论文

The next step of community health construction: Training general practitioners and implementing health management

Kan ZHANG MM, Wei DONG MM, Ying-Yao CHEN MD,

期刊论文

灵活可变的运动图像的分割算法

赵彦玲,张之超,高振,张庆超

期刊论文

Effects of carrier-attached biofilm on oxygen transfer efficiency in a moving bed biofilm reactor

Yanling WEI,Xunfei YIN,Lu QI,Hongchen WANG,Yiwei GONG,Yaqian LUO

期刊论文

Preliminary results of gentamycin combined with sodium bicarbonate for prevention of irinotecan-induced diarrhea

Qi MEI MM, Zhe CAO MM, Hua XIONG MD, Yuan CHEN MD,

期刊论文