bluuebunny/crossref_metadata_2025 huggingface dataset:
Establishment of a Brazilian Line of Human Embryonic Stem Cells in Defined Medium: Implications for Cell Therapy in an Ethnically Diverse Population
Authors: Fraga Ana M. , Sukoyan Marina , Rajan Prithi , De Almeida Ferreira Braga Daniela Paes , Iaconelli Assumpto , Franco José Gonçalves , Borges Edson , Pereira Lygia V.
Published: December 2010

Pluripotent human embryonic stem (hES) cells are an important experimental tool for basic and applied research, and a potential source of different tissues for transplantation. However, one important challenge for the clinical use of these cells is the issue of immunocompatibility, which may be dealt with by the establishment of hES cell banks to attend different populations. Here we describe the derivation and characterization of a line of hES cells from the Brazilian population, named BR-1, in commercial defined medium. In contrast to the other hES cell lines established in defined medium, BR-1 maintained a stable normal karyotype as determined by genomic array analysis after 6 months in continuous culture (passage 29). To our knowledge, this is the first reported line of hES cells derived in South America. We have determined its genomic ancestry and compared the HLA-profile of BR-1 and another 22 hES cell lines established elsewhere with those of the Brazilian population, finding they would match only 0.011% of those individuals. Our results highlight the challenges involved in hES cell banking for populations with a high degree of ethnic admixture.
Combined Application of Neutrophin-3 Gene and Neural Stem Cells is Ameliorative to Delay of Denervated Skeletal Muscular Atrophy after Tibial Nerve Transection in Rats
Authors: Lin Sen , Xu Jianguang , Hu Shaonan , Xu Lei , Zhang Changqing , Wang Yang , Gu Yudong
Published: December 2010

Examination of the therapeutic efficacy of neural stem cells (NSCs) has recently become the focus of much investigation. In this study we present an insight of the effects of combined application with neurotrophin-3 (NT-3) and NSCs that derived from rat embryo spinal cord on delaying denervated skeletal muscular atrophy after tibial nerve was severed. NT-3 gene was amplified by PCR and subcloned into lentiviral vector pWPXL-MOD to construct a lentiviral expression vector pWPXL-MOD-NT-3. A positive clone expressing NT-3 (named NSCs-NT-3) was obtained and used for differentiation in vitro and transplantation. Sixty adult rats, whose tibial nerves were sectioned, were divided into two groups: one grafted with NSCs-NT-3 (experimental group, n = 30) and the other with NSCs transfected by pWPXL-MOD (control group, n = 30). The cell survival and differentiation, NT-3 gene expression, and effect of delaying denervated skeletal muscular atrophy were examined through immunohistostaining, RT-PCR, Western blot, electrophysiological analysis, and mean cross-sectional area (CSA) of gastrocnemius, respectively. The results show that the NT-3 gene, which is comprised of 777 bp, was cloned and significantly different expression were detected between NSCs and NSCs-NT-3 in vitro. Quantitative analysis of the choline acetyltransferase (ChAT) immunopositive cells revealed a significant increase in experimental group compared to the control group 4 weeks after implantation ( p < 0.01). Twelve weeks after transplantation, the ChAT immunopositive cells were detected near the engrafted region only in experimental group. Furthermore, the effect in delaying denervated skeletal muscular atrophy is indicated in the EMG examination and mean CSA of gastrocnemius. These findings suggest that the neural stem cells expressing NT-3 endogenously would be a better graft candidate for the delay of denervated skeletal muscular atrophy.
Stem Cell Transplantation for Lymphoma Patients with HIV Infection
Authors: Michieli Mariagrazia , Mazzucato Mario , Tirelli Umberto , De Paoli Paolo
Published: December 2010

The advent of Highly Active Antiretroviral Therapy (HAART) has radically changed incidence characteristics and prognosis of HIV-positive patients affected by lymphomas. At this time there is consensus in the literature that, in first line, HIV-positive patients should always be treated with curative intent preferentially following the same approach used in the HIV-negative counterpart. On the contrary, an approach of salvage therapy in HIV-positive lymphomas is still a matter of debate given that for a wide range of relapsed or resistant HIV-negative Hodgkin's disease (HD) and non-Hodgkin lymphoma (NHL) patients, autologous peripheral or allogeneic stem cell transplantation are among the established options. In the pre-HAART era, therapeutic options derived from pioneering experiences gave only anecdotal success, either when transplantation was used to cure lymphomas or to improve HIV infection itself. Concerns relating to the entity, quality, and kinetics of early and late immune reconstitutions and the possible worsening of underlying viroimmunological conditions were additional obstacles. Currently, around 100 relapsed or resistant HIV-positive lymphomas have been treated with an autologous peripheral stem cell transplantation (APSCT) in the HAART era. Published data compared favorably with any previous salvage attempt showing a percentage of complete remission ranging from 48% to 90%, and overall survival ranging from 36% to 85% at median follow-up approaching 3 years. However, experiences are still limited and have given somewhat confounding indications, especially concerning timing and patients' selection for APSCT and feasibility and outcome for allogeneic stem cell transplant. Moreover, little data exist on the kinetics of immunological reconstitution after APSCT or relevant to the outcome of HIV infection. The aim of this review is to discuss current knowledge of the role of allogeneic and autologous stem cell transplantation as a modality in the cure of HIV and hemopoietic cancer patients. Several topics dealing with practical aspects concerning the management of APSCT in HIV-positive patients, including patient selection, timing of transplant, conditioning regimen, and relapse or nonrelapse mortality, are discussed. Data relating to the effects of mobilization and transplantation on virological parameters and pre- and posttransplant immune reconstitution are reviewed. Finally, in this review, we examine several ethical and legal issues relative to banking infected or potentially infected peripheral blood stem cells and we describe our experience and strategies to protect positive and negative donors/recipients and the health of caretakers.
Botanical Drugs and Stem Cells
Authors: Lin Po-Cheng , Chang Li-Fu , Liu Po-Yen , Lin Shinn-Zong , Wu Wan-Chen , Chen Wuen-Shyong , Tsai Chang-Hai , Chiou Tzyy-Wen , Harn Horng-Jyh
Published: December 2010

The potential to generate virtually any differentiated cell type from stem cells offers the possibility of creating new sources of cells for regenerative medicine. To realize this potential, it will be essential to control stem cell differentiation. Chinese herbal medicine is a major aspect of traditional Chinese medicine and is a rich source of unique chemicals. As such, individual herbs or extracts may play a role in the proliferation and differentiation of stem cells. In this review, we discuss some of the Chinese herbal medicines that are used to treat human diseases such as neuronal degenerative diseases, cardiovascular diseases, and osteoporosis. We also describe the relationship between Chinese herbal medicines and stem cell regulation.
The Role of Cancer Stem Cells (CD133+) in Malignant Gliomas
Authors: Cho Der-Yang , Lin Shinn-Zong , Yang Wen-Kuang , Hsu Den-Mei , Lin Hung-Lin , Lee Han-Chung , Lee Wen-Yeun , Chiu Shao-Chih
Published: December 2010

Malignant gliomas, particularly glioblastoma multiforme (GBM) tumors, are very difficult to treat by conventional approaches. Although most of the tumor mass can be removed by surgical resection, radiotherapy, and chemotherapy, it eventually recurs. There is growing evidence that cancer stem cells (CSCs) play an important role in tumor recurrence. These stem cells are radioresistant and chemoresistant. The most commonly used tumor marker for CSCs is CD133. The amount of CSC component is closely correlated with tumor malignancy grading. Isolating, identifying, and treating CSCs as the target is crucial for treating malignant gliomas. CSC-associated vascular endothelial growth factor (VEGF) promotes tumor angiogenesis, tumor hemorrhage, and tumor infiltration. Micro-RNA (miRNA) plays a role in CSC gene expression, which may regulate oncogenesis or suppression to influence tumor development or progression. The antigenesis of CSCs and normal stem cells may be different. The CSCs may escape the T-cell immune response. Identifying a new specific antigen from CSCs for vaccine treatment is a key point for immunotherapy. On the other hand, augmented treatment with radiosensitizer or chemosensitizer may lead to reduction of CSCs and lead to CSCs being vulnerable to radiotherapy and chemotherapy. The control of signaling pathway and cell differentiation to CSC growth is another new hope for treatment of malignant gliomas. Although the many physiological behavioral differences between CSCs and normal stem cells are unclear, the more we know about these differences the better we will be able to treat CSCs effectively.
The Treatment of Neurodegenerative Disorders Using Umbilical Cord Blood and Menstrual Blood-Derived Stem Cells
Authors: Sanberg Paul R. , Eve David J. , Willing Alison E. , Garbuzova-Davis Svitlana , Tan Jun , Sanberg Cyndy D. , Allickson Julie G. , Cruz L. Eduardo , Borlongan Cesar V.
Published: December 2010

Stem cell transplantation is a potentially important means of treatment for a number of disorders. Two different stem cell populations of interest are mononuclear umbilical cord blood cells and menstrual blood-derived stem cells. These cells are relatively easy to obtain, appear to be pluripotent, and are immunologically immature. These cells, particularly umbilical cord blood cells, have been studied as either single or multiple injections in a number of animal models of neurodegenerative disorders with some degree of success, including stroke, Alzheimer's disease, amyotrophic lateral sclerosis, and Sanfilippo syndrome type B. Evidence of anti-inflammatory effects and secretion of specific cytokines and growth factors that promote cell survival, rather than cell replacement, have been detected in both transplanted cells.
Characterization of Axon Formation in the Embryonic Stem Cell-Derived Motoneuron
Authors: Pan Hung-Chuan , Wu Ya-Ting , Shen Shih-Cheng , Wang Chi-Chung , Tsai Ming-Shiun , Cheng Fu-Chou , Lin Shinn-Zong , Chen Ching-Wen , Liu Ching-San , Su Hong-Lin
Published: December 2010

The developing neural cell must form a highly organized architecture to properly receive and transmit nerve signals. Neural formation from embryonic stem (ES) cells provides a novel system for studying axonogenesis, which are orchestrated by polarity-regulating molecules. Here the ES-derived motoneurons, identified by HB9 promoter-driven green fluorescent protein (GFP) expression, showed characteristics of motoneuron-specific gene expression. In the majority of motoneurons, one of the bilateral neurites developed into an axon that featured with axonal markers, including Tau 1, vesicle acetylcholine transporter, and synaptophysin. Interestingly, one third of the motoneurons developed bi-axonal processes but no multiple axonal GFP cell was found. The neuronal polarity-regulating proteins, including the phosphorylated AKT and ERK, were compartmentalized into both of the bilateral axonal tips. Importantly, this aberrant axon morphology was still present after the engraftment of GFP+ neurons into the spinal cord, suggesting that even a mature neural environment fails to provide a proper niche to guide normal axon formation. These findings underscore the necessity for evaluating the morphogenesis and functionality of neurons before the clinical trials using ES or somatic stem cells.
Construction of a Portal Implantable Functional Tissue-Engineered Liver Using Perfusion-Decellularized Matrix and Hepatocytes in Rats
Authors: Bao Ji , Shi Yujun , Sun Huaiqiang , Yin Xiangli , Yang Ruina , Li Li , Chen Xi , Bu Hong
Published: December 2010

Innovative cell-based therapies, including hepatic tissue engineering following hepatocyte transplantation, are considered as theoretical alternatives to liver transplant or for partial replacement of liver function in patients. However, recent progress in hepatic tissue engineering has been hampered by low initial hepatocyte engraftment and insufficient blood supply in vivo. We developed an intact 3D scaffold of an extracellular matrix (ECM) derived from a decellularized liver lobe, with layer-by-layer (LbL) heparin deposition to avoid thrombosis, which we repopulated with hepatocytes and successfully implanted as a tissue-engineered liver (TEL) into the portal system. The TEL provided sufficient volume for transplantation of cell numbers representing up to 10% of whole-liver equivalents and was perfused by portal vein blood. Treatment of extended hepatectomized rats with a TEL improved liver function and prolonged survival; mean lifespan was extended from 16 to 72 h. At 72 h postoperation, the TEL sustained functional and viable hepatocytes. In conclusion, we propose the TEL as a state-of-the-art substitute for whole-liver transplantation and as a proof of concept for the technology that will eventually allow for the transplantation of a reconstituted liver.
Amniotic Fluid as a Rich Source of Mesenchymal Stromal Cells for Transplantation Therapy
Authors: Antonucci Ivana , Stuppia Liborio , Kaneko Yuji , Yu Seongjin , Tajiri Naoki , Bae Eunkyung C. , Chheda Sonia H. , Weinbren Nathan L. , Borlongan Cesar V.
Published: December 2010

Stem cells isolated from amniotic fluid are known to be able to differentiate into different cells types, thus being considered as a powerful tool for cellular therapy of different human diseases. In the last 4 years, amniotic fluid-derived stem (AFS) cells have been shown to express embryonic and adult stem cell markers. These cells can be considered an intermediate stage between embryonic stem cells and adult stem cells. AFS cells can give rise to adipogenic, osteogenic, myogenic, endothelial, neurogenic, and hepatic lineages, inclusive of all embryonic germ layers. AFS cells have a high renewal capacity and can be expanded for over 250 doublings without any detectable loss of chromosomal telomere length. Taken together, all these data provide evidence that amniotic fluid represents a new and very promising source of stem cells for research, as well as clinical applications. Certainly stem cells from amniotic fluid will be useful both for a customized cell supply for newly born children and for banking cells to be used for therapeutic cell transplantation in immunogically matched recipients. Further investigations are also warranted to fully explore the amniotic cells' potential for adult human disorders.
Use of a Clinically Approved Iron Oxide MRI Contrast Agent to Label Human Hepatocytes
Authors: Puppi Juliana , Mitry Ragai R. , Modo Michel , Dhawan Anil , Raja Kishor , Hughes Robin D.
Published: December 2010

Reliable noninvasive methods are needed to monitor cell engraftment and graft survival after hepatocyte transplantation. Superparamagnetic iron oxide nanoparticles (SPIOs) have been shown to accumulate in various types of cells, and are currently the labeling agent of choice for cellular magnetic resonance imaging (MRI). However, for successful clinical translation to hepatocyte transplantation, it is important that hepatocytes maintain their viability and synthetic function after labeling. In this study, primary human hepatocytes were incubated with increasing concentrations of clinical grade SPIOs for different time intervals. SPIOs uptake was confirmed by light and fluorescence microscopy, and intracellular iron content quantified by a colorimetric ferrozine-based assay. Studies were performed to determine if labeling affected cell viability and function. Intracellular iron concentrations increased in a time- and dose-dependent manner after incubation with SPIOs. Labeling had minimal short-term effects on cell attachment and mitochondrial function. However, exposure of hepatocytes to SPIOs resulted in a dose- and time-dependent reduction in protein synthesis. Cell labeling for 16 h had no significant effect on hepatocyte-specific function, but longer periods of incubation resulted in a dose-dependent decrease in albumin production. Hepatocytes incorporated SPIOs at sufficient levels for in vitro detection on a 7-T MRI imaging system, with a minimum of 2,000 SPIO-labeled cells/μl detected by a decreased T2 relaxivity compared to controls. Intrasplenic transplantation of human hepatocytes labeled with 50 μg Fe/ml of SPIOs was performed in nonobese diabetic/severe combined immune deficiency (NOD-Scid) mice. Recipient livers showed a clear decrease in signal intensity on T2*-weighted MR images when compared to controls, allowing detection of hepatocytes. With further experiments to optimize the conditions for labeling human hepatocytes, it should be possible to apply this technique to track hepatocyte transplantation in patients with liver disease.
Bioreactor for the Long-Term Culture of Lung Tissue
Authors: Petersen Thomas H. , Calle Elizabeth A. , Colehour Maegen B. , Niklason Laura E.
Published: December 2010

In this article we describe the design and validation of a bioreactor for the in vitro culture of whole rodent lung tissue. Many current systems only enable large segments of lung tissue to be studied ex vivo for up to a few hours in the laboratory. This limitation restricts the study of pulmonary biology in controlled laboratory settings, and also impacts the ability to reliably culture engineered lung tissues in the laboratory. Therefore, we designed, built, and validated a bioreactor intended to provide sufficient nutrient supply and mechanical stimulation to support cell survival and differentiation in cultured lung tissue. We also studied the effects of perfusion and ventilation on pulmonary cell survival and maintenance of cell differentiation state. The final bioreactor design described herein is capable of supporting the culture of whole native lung tissue for up to 1 week in the laboratory, and offers promise in the study of pulmonary biology and the development of engineered lung tissues in the laboratory.
Transplant of Primary Human Hepatocytes Cocultured with Bone Marrow Stromal Cells to SCID Alb-uPA Mice
Authors: Mohajerani S. A. , Nourbakhsh M. , Cadili A. , Lakey J. R. , Kneteman N. M.
Published: December 2010

Hepatocytes are vulnerable to loss of function and viability in culture. Modified culture methods have been applied to maintain their functional status. Heterotypic interactions between hepatocytes and nonparenchymal neighbors in liver milieu are thought to modulate cell differentiation Cocultivation of hepatocyte with various cell types has been applied to mimic the hepatic environment. Bone marrow stromal cells (BMSC) are plastic cell lines capable of transforming to other cell types. In this study hepatocyte coculture with BMSCs achieved long-term function of human hepatocytes in culture for 4 weeks. In vitro functional status of human hepatocytes in BMSC coculture was compared with fibroblast coculture and collagen culture by measuring albumin, human-α-1-antitrypsin (hAAT), urea secretion, CYP450 activity, and staining for intracellular albumin and glycogen. After 2 weeks in culture hepatocytes were retrieved and transplanted to severe combined immunodeficiency/albumin linked-urokinase type plasminogen activator (SCID Alb-uPA) mice and engraftment capacity was analyzed by human hepatic-specific function measured by hAAT levels in mouse serum, and Alu staining of mouse liver for human hepatocytes. Hepatocytes from BMSC coculture had significantly higher albumin, hAAT secretion, urea production, and cytochrome P450 (CYP450) activity than other culture groups. Staining confirmed the higher functional status in BMSC coculture. Transplantation of hepatocytes detached from BMSC cocultures showed significantly higher engraftment function than hepatocytes from other culture groups measured by hAAT levels in mouse serum. In conclusion, BMSC coculture has excellent potential for hepatocyte function preservation in vitro and in vivo after transplant. It is possible to use BMSC hepatocyte coculture as a supply of cell therapy in liver disease.
Research and Design of Novel Fractal Reader Antenna
Authors: Chen Zu Jue , Zhong Zhi Hui , Yan Shu
Published: December 2010

This paper researches how the various iterations affect the characteristics of Minkowski fractal microstrip patch antenna. A 2-itration Minkowski fractal reader antenna is designed. In order to increase antenna bandwidth, the structure of a novel modified antenna is presented to operate at 2.45GHz with the return loss of -35.15dB and bandwidth of 180MHz, the maximum gain of which is 7.83dB. Besides, with its size of 30mm ×30mm, this antenna area is decreased by 43.75% and the width is decreased by 25% compared to normal square patch antenna. The simulation results show that it has a good size-reduction feature that can well meet the requirement for handheld RFID reader under certain size and characteristics.
Research on MR Active Damping Control in Large-Diameter High-Speed Ball Mill
Authors: Chen Qi Dong , Rui Yan Nian , Jiang Xiao Mei , Shen Ming
Published: December 2010

In this paper, MR damping mechanism is used to solve the vibration damping difficulties caused by the nonlinear vibration of ball mill. Dynamic model of MR Damper is constructed to design the damper of ball mill through research. Fuzzy control principle is adopted for active control of the MR damper and satisfactory results are obtained through computer simulation.
Design of Multi-Wire Saw Winding System
Authors: He Jing Liang , Dong He Yuan , Ye Xiao Yan , Wang Xue Jun
Published: December 2010

On the basis of the analysis of winding drive system’s technological requirements of multi-wire cutting system and the characteristics of torque motor, the article proposes a scheme of wrap wheel with torque motor control to overcome the deficiency of the general control motor driven wrap wheel. In determination process of winding system parameter, it provides the selective calculation methods and the control strategy of the torque motor. According to processing materials, we get tension values, and then calculate the output torque, and choose a suitable torque motor and determine the control strategy. Then the design process of winding drive system finishes. Adopting the torque motor as wrap wheel control motor can make wrap device to meet the system requirements. Meanwhile it can simplify the structure of wrap device, and make the cutting-process runs smoothly.
Method for Error Removal of Intelligent Electronic Counting Instruments
Authors: Li Zhen Liang , Fan Jun Gang , Li Ya
Published: December 2010

In this paper, a method is introduced to remove the counting errors of electronic counting instruments, which contains two aspects to remove the errors caused by outside interference and to remove the counting errors caused by quality error of the object respectively. Counting errors of object can be removed effectively by program of software system. As a result, it’s proven to be effective and stable by applying it into practice.
A Test System of Flow Characteristic Based upon PLC for Control Valve
Authors: Wang Geng Fang
Published: December 2010

The flow characteristics of control valve are very important to product quality. For measuring the flow coefficient and flow curve accurately and all-rounding, we have designed a test system,which worked with PLC, it can measure the flow characteristics and resistance coefficient of control valve. The main purpose of this study was to bring out the work elements, design feature, and test software.The study we have performed showed that this test system is reasonable, easy to support entire automatic measurement with high precision and easy operation.
The Form Error Inspection of Turbine Blade with Coordinate Measuring Machine
Authors: Guo Hui , Su Na , Lin Da Jun
Published: December 2010

The form error of turbine blade impacts on the work performance of turbine directly. To inspect the blade form error, the cross section curve of turbine blade is constructed as NURBS by interpolating design points in the paper, then the mathematical model of form error of blade is developed by searching for four control points of the minimum distance between measure points and design curve, and the particle swarm optimization (PSO) is applied for solving the minimum distance between measure points and design curve. Comparing with BFGS and DFP, the experiment results show the proposed method is effective in inspecting the blade form error.
Dynamic Response of Conductor Breakage for Oxytropis Transmission Tower-Line System
Authors: Li Ran , Gao Qiang
Published: December 2010

Dynamic response of conductor breakage is analyzed on guyed oxytropis transmission tower-line system of 500KV 5291 JinJiang-Zhenjiang lines. Considering unbalanced tension, finite element method is presented. Result of the transient analysis shows that the vibration of tower-line system happens after conductor breakage. With the damping affect，the system vibration becomes gentle. For the tension of lines, the peak value of dynamic tension of conductor can be times of the initial tension. It is shown that the proposed method is of efficiency and practicality.
The Aquaculture Multi-Parameter Monitoring System
Authors: Liu Yi Ying
Published: December 2010

This paper introduces an aquaculture multi-parameter monitoring system. The hardware structure of the system is introduced, the software design of the system is described in detail and the flow charts of the key functions are presented. By using the Profibus-DP field bus, more monitoring stations are joined together to constitute a distributed monitoring and controlling network, which has functions like accurate signal collecting, real-time signal analyzing and processing and automatic alarm. The system can not only improve the accuracy and stability of parameter monitoring, but also enlarge the monitoring range, convenient the water environment monitoring and managing, reduce the cost of equipment and production. It can apply to the large aquaculture enterprises.
Design of RFID Sensor-Tag for Wireless Monitoring of SMA-Reinforced Composite Structure
Authors: Qiu Zi Xue , Wu Jing Ya , Yuan Jiang , Chen Yu Tian , Yang Yong Jie
Published: December 2010

When Shape memory alloy (SMA) wires are embedded in the composite structure with a specific volume fraction, the properties of the resulting hybrid composite structure, which is called SMA-reinforced composite structure, will be reinforced. Some of SMA wires embedded in the composite can be viewed as two electrodes of the capacitor. The deformation of the composite structure will cause change of the capacitor, therefore the segmental SMA wires embedded in the composite may be considered as the self-sensitive element of structure strain monitoring. The measurement circuit monitoring the change of micro capacitor in structure is designed, and it is integrated with radio frequency identification (RFID) technology to compose RFID sensor-tag, and the variation of capacitor is send to the RFID reader wirelessly to form a wireless health monitoring system. Experimental results show that this RFID sensor-tag and its system can be feasibly used in wireless structural health monitoring of SMA-reinforced composite structure.
A New Model of Stochastic Resonance Used in Weak Signal Detection
Authors: Zhao Wen Li , Wang Zhi Gang , Huang Zhen Qiang
Published: December 2010

A new model is introduced in this article with which high frequency weak signal could be detected from strong noise background effectively. And meanwhile the process is displayed perfectly by using computer simulation. It will play an important role in detecting high frequency signal concealed in noise .Which can be used in detecting fault condition signals of mechanical system.
Design and Research of High Precision Internal Grinding Embedded CNC System
Authors: Xie Ou , Li Hua , Li Zheng , Yin Zhen
Published: December 2010

A design solution of machine tool control system and its hardware and software design were proposed for the requirement of high precision internal grinding. The ARM microprocessor was used as the system control center and the technical grade touch screen was used as the human machine interface. The feed motion of the X, Z 2-axis servo motor was controlled by the system to complete the grinding path, and the machine tool switching signal was controlled by the Soft PLC Technology. The whole system has the advantage of stable, high performance and user friendly, meeting the requirement of high precision grinding.
A Novel Fuzzy-PID HFFT Controller to Advance on the Dynamic Characteristics
Authors: Hu Xiong Xin
Published: December 2010

Structural components are subjected to high-frequency vibration. But today, the fatigue tester is required to provide higher precision, robust system performance and more powerful functionality because of the increasing arduousness of industrial material selection. The novel fuzzy-PID HFFT (High frequency fatigue tester) controller advances on the static/dynamic load accuracy, the running stability, the resonant frequency seeking ability, and the frequency stability. Firstly the HFFT mechanical system model is introduced. Secondly the HFFT controller is developed, which includes the static/dynamic load control loop and the frequency locked loop. Finally some experimental data in PLG-100 are shown. Compared to the conventional PID system, the fuzzy-PID tester’s accuracy is higher, and the load/frequency control loops possess the premium dynamic characteristics.
Tooth Contact Analysis of Planetary Gear Trains with Equally Spaced Planets
Authors: Xu Kai , Deng Xiao Zhong , Yang Jian Jun , Dong Guan Qiang
Published: December 2010

Based on Tooth Contact Analysis (TCA), a feasible approach for Transmission Error (TE) of planetary gear train is proposed in this paper. With a view to getting the total TE curve of the planetary gear train, a specific analysis of the TE from the planetary gear train with only one planet should be proceed firstly, the second step is to calculate each phase difference of planets in the gear train. The applicable conditions for the simplified calculation are spur gear or involute gear pairs in the gear train. Due to equal space between them, planets have the same phase angle.
Design of Universal Straw Cutting Mill
Authors: Xu Yun Feng , Li Ping Ping , Zhang Xi Liang
Published: December 2010

For the low status of straw utilization, in order to improve the mass production rate and reduce energy consumption, according to the classification principle and the idea of “first cut ,second crush”, a set of cutting, screening, crushing, and re-screening as one of the universal closed type straw cutting mill was designed. Design plan was set, the structure diagram of the process of cutting and screening was given, major working parts such as the feeding body, cutting body, shattered body were designed and calculated, the cutting and crushing productivities was 0.29t/h and 0.32t/h respectively, matching power was 10KW. It plays an important role on the richness variety of straw processing equipments, increase straw utilization, and reduction energy consumption.
Virtual System of NC Milling Based on 3ds Max and Open GL Modeling
Authors: Ding Zu Jun , Ni Jun Fang , Lu Li Li , Xu Xiao Wei
Published: December 2010

This virtual system, which is based on virtual manufacturing and NC processing technique for NC milling, is developed by Visual C++6.0. The system can edit, check and debug the NC programs to realize the 3D dynamic simulation of machining processes and collision-checking during cutting processes.
Finite Element Analysis and Development for a New Draft Gear of Locomotive Couplers
Authors: Wei Yan Gang , Wang Lan Qing , Zhang Xiu Juan
Published: December 2010

In order to solve the existing problems of domestic applications, an innovative structure design for the draft gears of locomotive couplers is developed using the mechanical principles and the finite element method. In the condition of ensuring the performance, the draft gear structure is optimized, the number of draft gear parts is reduced, and the weight and cost of draft gear are cut down. After absorbing the foreign technologies, a new locomotive coupler draft gear is developed which achieves the equivalent-level performances as those of developed countries and fills the domestic gap.
Study on the Inner Helical Gear Form Grinding Wheel Dressing Technology
Authors: Su Jian Xin , Deng Xiao Zhong , Ren Xiao Zhong , Xu Kai
Published: December 2010

Based on the gear meshing theory, the mathematical model of inner helical gear form grinding is established. In order to get rid of the grinding interference, numerical simulation is used to optimize the diameter of grinding wheel and its installation angle. The wheel profile obtained by means of numerical simulation is transformed into the end section of tooth firstly, and then compared with the theoretical involute tooth. Substitute the optimized diameter of grinding wheel and its installation angle into meshing equation, the wheel profile can be obtained by solving meshing equation with Newton iteration method. Wheel dressing and simulating analysis software are prepared based on VC++6.0.
Clearance Identification of Beam Structure Using Free Vibration Method
Authors: Zhu Xiao Dong , Jin Dong Ping , Feng Zhi Hua
Published: December 2010

The clearances, which universally exist in the joint parts of mechanical systems, are a main cause of various operation deteriorating problems, including noises generating, material wearing, even the early fatigue of members. In this paper, a new method to determine the clearance magnitude in the beam support is proposed with the description of a numerical example. The growing clearance will increase the vibration period of realistic system, and the accurateness of measurement is relevant to the frequency resolution of the instrument. Through the time series of the midpoint response of a simply supported beam, the period of the first modal free vibration can be obtained using the FFT Algorithm. Only two responses from different initial conditions are needed to identify the magnitude of the clearance. It is estimated the accurateness could be below 15%. The investigation also suggests this free vibration period approach may be adapted to handle the energy losses situations with the damping ratio considered in the formulas.
Research on the Equipment for Electrostatic Flocking of the Activated Carbon Fibers
Authors: Wu Qiang , Qian Yong Ming , Wang Qian , Zhou Yi Dan
Published: December 2010

Based on the analysis of the equipment requirements for the "upper-adsorption” electrostatic flocking method of the Activated Carbon Fibers, the overall design of equipment is given, and the electrostatic system, the main function equipments and control systems of the device are also introduced separately.
Kinematics Analysis and Workspace Analysis of a New Kind of Stabilized Platform
Authors: Ninɡ Menɡ , Hao Jing Ru , Sun Jiang Hong
Published: December 2010

This paper introduces a electro-hydraulic servo and horizontal stabilized platform driven by hydraulic cylinder. This platform can make the table maintain horizontal. The structural analysis, kinematics analysis and workspace analysis were carried out to the platform. Through establishing kinematics model and Using MATLAB software, kinematics simulation computation is given to the mechanism.
Effect of Strain Rate on Tensile Properties of Tissues in Tail Flukes of Dolphin
Authors: Sun Qi Long , Morikawa Hirohisa , Kobayashi Shunichi , Ueda Keiichi , Miyahara Hirokazu , Nakashima Motomu
Published: December 2010

The mechanical properties of the tissues relates with the propulsive performance of the tail fins of dolphins. In this study, the tensile properties of the main two tissues in the tail flukes of a dolphin, that is, the ligamentous layer and dense connective tissue are investigated. As a result, the tissues all showed the effect of the strain rate which weakened gradually as the strain increased. The moduli obtained at different strain rates tend to converge.
Study on the Mechanical Properties of the Elliptic Ultrasonic Vibration Cutting Process
Authors: Li Hua , Cao Zi Yang
Published: December 2010

In this paper,the mechanical properties of the elliptic ultrasonic vibratioon cutting were proposed systemiticaly through thoretical analysis，the model of the average cutting force in the elliptic ultrasonic vibration cutting process was established. The performance of the the properties to the machining acurracy and the surface roughness was studied through experiment.
A Study on the Ni-P-SiC Coating of AZ91D Magnesium Alloy
Authors: Ge Xiao Lan , Zeng Bing , Chen Zhi Chao , Wei Duo , Wang Cai Jun
Published: December 2010

An Investigation on the Ni-P-SiCp Electroless Composite Plating of AZ91D magnesium alloy was investigated.The morphology and phase structrue of the electroless composite plating were investigated by means of SEM and XRD.The effect of concentration of the second phase particle in electroless plating solution on wear resistance of the Ni-P-SiCp composite coating were studied.The properties of the coatings before and after heat treatment were compared.The result shows that the obtained coatings were flat and compact.X-ray diffractometry indicated that the coatings were amorphous,but crystallization would happen in the process of heat treatment.From the lost weight of the coatings it can be seen that the wear resistance of composite coatings was better than that of Ni-P coatings .
Research on Kinematic Chain Isomorphism Identification Method Based on the Standardization Adjacent Matrix
Authors: Ge Mao Zhong , Xiang Jian Yun , Zhang Yong Kang
Published: December 2010

In order to solve a baffling problem of kinematic chain isomorphism identification, proceeded from the isomorphism’s principles of graph theory, a new method for detecting isomorphism among planar kinematic chains using the standardization adjacent matrix is presented in this paper. The general course of adjacent matrix standardization processing and numbering principle of node are introduced, the implementation of this new method is illustrated with an example, it is showed that this new method can be accurately and effectively performed.
Investigation on Tooth Face Width Characteristics of Offset Face-Gear Drive
Authors: Li Da Qing , Deng Xiao Zhong , Wei Bing Yang
Published: December 2010

The tooth face width characteristics of offset face-gear drive are considered in this paper. Base on the generation process of offset face-gear, the analytical geometry of the offset face-gear drive is derived. The conditions of undercutting and pointing for offset face-gear are studied, the expressions of inner radius and outer radius able to avoid undercutting or pointing are presented. The effects of the tooth number of the shaper, gear ratios and offset distance on undercutting, pointing and tooth face width of offset face-gear are analyzed, respectively. The expressions of approximate solution for inner radius and outer radius are provided.
The Electric Field Analysis of the Structure of New Micro-Machined Gyroscope
Authors: Huang Kang , Qian Gen , Liang Qing Song , Qu Yu Feng
Published: December 2010

The structure of current micro-machined gyroscope result in detection error and processing difficulty, which can be reduced by redesigning the structure such as a new type researched here to enhance the accuracy..The new structure for gyroscope and the method of driving force calculating for it is introduced in this paper. A 3D micro-machined gyroscope model has been built through CAD software, while finite model through CAE software. Besides, the driving structure has been analyzed to gain the size of driving force and electric-field distribution.
Study on the Fuzzy Control of Coach Air Suspension System
Authors: Li Mei , Li Zhong Xin , Guo Ji Wei , Shen Xu Feng
Published: December 2010

An electronically controlled air suspension system has been introduced to improve the ride performance of a vehicle. A fuzzy controller is designed on the basis of fuzzy logic control strategy which is applied to control the air suspension system. The vibration reduction of a coach with the suspension system is achieved by controlling the stiffness of the air spring and the damping of a switchable damper. A nonlinear dynamic model of a half-vehicle is used to simulate traditional air suspension and the one with fuzzy controller for ride performance respectively on road input. The results indicate that implementing a control strategy can improve the ride performance of the coach on the condition of normal road.
The Dynamic Analysis of Self-Anchored Suspension Bridge Based on Ansys
Authors: Xing Bang Sheng , Du Changlun , Wang Xue Feng
Published: December 2010

In this paper Ansys, the difite element analysis software, is used to make model analysis on self-anchored suspension bridges achieve the intrinsic frequency and inherent vibrating mode of its first ten bands. Simutaneously, a transient dynamic analysis is made to research the impact of the deformation of the self-suspension bridge under a moving load with the change of the speed, which will be playing a pivotal role in the design and construction of the self-anchored suspension bridges.
Influence of La2O3 Doping Amount on Properties of NBT-KBT-BT Lead-Free Piezoelectric Ceramics
Authors: Huang Xin You , Gao Chun Hua , Wei Min Xian , Chen Zhi Gang
Published: December 2010

0.85(Na0.5Bi0.5)TiO3-0.144(K0.5Bi0.5)TiO3-0.006BaTiO3(NBT-KBT-BT) lead-free piezo -electric ceramics were prepared using conventional solid state method. The influence of La2O3 doping amount on the crystal phase, surface microstructure and properties of the NBT-KBT-BT lead free piezoelectric ceramics were investigated using X-ray diffraction(XRD), Scanning electron microscopy(SEM) and other analytical methods. The results show that La2O3 has diffused into the lattice of NBT-KBT-BT ceramics. Consequently, a pure perovskite phase is formed. SEM images show that the microstructure of the ceramics is changed with the addition of a small amount of La2O3, La2O3 doping can make grain growing. The piezoelectric strain constant(d33) starts increasing and then decreasing, the dielectric constant(εT33/ε0) increases continuously and the dielectric loss(tanδ) starts increasing and then decreasing and then increasing when La2O3 doping amount increases. When the doping amount of La2O3 is 0.4wt.% and the sintering temperature is 1160°C, the NBT-KBT-BT piezoelectric ceramics with good comprehensive properties can be obtained. Its piezoelectric strain constant(d33), dielectric constant(εT33/ε0), and dielectric loss(tanδ) are 151pC/N, 1543 and 4.2%, respectively.
Research on Automatic Programming System of High Speed Wire Cutting Machine
Authors: Cheng Kun , Ni Jun Fang , Lv Li Li , Ding Zhu Jun , Xu Xiao Wei
Published: December 2010

Programming of graphical interaction and modular structure are adopted in this wire cutting machine software by analyzing the structure of DXF file, picking out the part’s outline information in Visual C++ 6.0, and combining the manufacture conditions in this paper. The NC codes are obtained which are consistent with the high-speed cutting machine processing system automatically. This system software greatly facilitates the process of high speed cutting machine, shortens programming time and improves the accuracy of the programming.
Experimental Study on Testing Ni-Containing Stainless Steel Protective Coatings by Pulsed Laser Scratching
Authors: Feng Ai Xin , Cao Yu Peng , Xu Chuan Chao , Sun Huai Yang , Ni Gui Fen , Wang Jun Wei , Zhou Peng Chen
Published: December 2010

In the experiment, we use pulsed laser to conduct discrete scratching on Ni-containing stainless steel protective coatings to test residual stress situation after the matrix is scratched; then to analyze the the impact of the impact stress wave on coating - substrate bonding strength according to the test results, finally to infer the laser power density range within which it occurs coating failure. The study shows that: after laser discrete scratching, the residual stress of the center of the laser-loaded point on matrix surface gradually reduces when the pulsed laser power density increases. The matrix produces a corresponding residual compressive stress under the laser power density reaches a certain value. The actual failure threshold values are 12.006 GW/cm2, 11.829GW/cm2 and 12.193GW/cm2 measured by the three-dimensional topography instrument testing the discrete scratch point of three groups of samples and verified by using a microscope
Transient Dynamic Analysis of Machine Ram
Authors: Li Long , Fu Ge Yan , Zhu Ning , Lu Hua Qiang
Published: December 2010

The movement of the electrode of SEDM (Fig. 1) brings dynamic forces, therefore this paper utilize FEM to analyze the load conditions of the machine. An analysis shows that the ram is the component which impacts the machine accuracy greatly; Through transient dynamic analysis of the ram，the paper gets diagrams of displacement, stress and reaction force versus time, and analyzes the solution results to get the relationship between the joints and the machine accuracy.
Structural Analysis of a Teat Cup Liner
Authors: Adachi Sho Hei , Bao Li Min , Yamazaki Osamu
Published: December 2010

This study attempts to analyze the structure of the thin-walled part in the teat cup liner for FEM by the finite-element method (FEM) and to determine the most suitable structure for it. For the first step, we prepared a specimen liner made from NBR (Acrylonitrile-Butadiene Rubber) and silicon rubber (made by ORION MACHINERY CO., LTD.) and conducted tensile and compression tests for mechanical scraping properties of rubber Data. We then analyzed the thin-walled part using SolidWorks Simulation (SolidWorks Corporation) for finite-element analysis in liner process from expression of milk into nipple massage.
Investigation on Shock Pressure Absorbing Approaches for a Hydraulic Vibration Generator
Authors: Wang Yong , Zhu Guo Niu , Wei Tao
Published: December 2010

Shock pressure and its absorbing approaches in hydraulic vibration generator for a vehicle body test-bed are discussed in this paper. The principle and characteristics of the hydraulic vibration excitation system are introduced. The main parameters that determine the performance of hydraulic system are calculated and designed. Pressure shocking problem in operation and its absorbing approaches are discussed from theoretical and experimental aspects. An optimal combination of accumulators and common solenoid direction control valve and their parameter configuration and neutral position type selection are obtained in conclusion. Practical usage had approved the feasibility of the design presented in this paper.
Flow Numerical Simulation of Centrifugal Pump with Splitting Blades Based on RE
Authors: Ren Nai Fei , Chen Ming Min , Jiang Jie , Cheng Li
Published: December 2010

The structure of the centrifugal pump with splitting blades is complex, and the law of the internal flow is not fully grasped. Therefore Reverse Engineering (RE) and numerical simulations of Computational Fluid Dynamics (CFD) are adopted to study the centrifugal pumps with splitter blades. In this process, the law of velocity and pressure distribution of internal flow about the centrifugal pump with splitter blades is preliminary disclosed. In addition, performance prediction was carried out in centrifugal pumps. Comparing to the calculation curve and text characteristic curve, it’s obvious that simulation results are in good agreement with experimental results. The results verify the reliability and feasibility of the research method.