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Objective To explore whether the enrichment of cancer stem cells (CSCs) in colorectal cancer by suspension culture method is involved with epithelial-mesenchymal transition (EMT). Methods 3D microspheres were cultured by suspension culture method to human colorectal cancer SW620 cells. The 3D microspheres and SW620 cells were used as the research objects. To clarify whether 3D microspheres were enriched with CSCs, we made tumorigenicity experiments in NOD/SCID mice, soft agar cloning experiments, and detected the expression levels of cancer stem cells markers CD44 and Ep-CAM by flow cytometry or by Western blotting. The protein expression levels of EMT markers such as E-cadherin, N-cadherin and vimentin were detected by Western blotting. Results Compared with the parental SW620 cells, colony formation in vitro (P

It is important to choose the best spatial interpolation method to reflect spatial distribution features and evaluate soil heavy metal pollution. The spatial distribution of arsenic (As) and cadmium (Cd) concentrations in top soil samples from Hubei Province were studied by four frequently-used spatial interpolation methods, including inverse distance weighted (IDW), radial basis function (RBF), local polynomial interpolation (LPI) and ordinary kriging (OK). The interpolation precision and effect of the spatial distribution of the four methods were compared with the results of cross validation and spatial distribution, and the pollution was assessed by the geoaccumulative index (I

OCT4B1, a splice variant of OCT4, is a key regulator in maintaining the properties of pluripotency and self-renewal in embryonic stem (ES) cells. Recent results have shown that OCT4B1 is involved in tumorigenesis. However, the contribution of OCT4B1 in the tumorigenesis and drug resistance of colon cancer remains to be determined. The aim of the present study was to determine whether OCT4B1, which maintains the stemness of ES cells, promoted cell growth by facilitating transition of the cell cycle and reduced apoptosis in colon cancer and drug‑resistant cells using flow cytometry and western blotting. The results showed that, OCT4B1 promoted the growth of colon cancer and drug‑resistant cancer cells by maintaining the activity of ES cells and by facilitating the transition of the cell cycle and reducing apoptosis. Additionally, OCT4B1 was able to reduce sensitivity to oxaliplatin by altering the expression of two important mediators in drug resistance, P-gp and ABCG2 [ATP-binding cassette, sub‑family G (WHITE), member 2]. Furthermore, OCT4B1 enhanced the ability of migration and invasion through alteration of the epithelial-to-mesenchymal transition (EMT) in colon cancer. In conclusion, to the best of our knowledge, the results demonstrated for the first time that OCT4B1 functions as an oncogene in colon cancer and provides the development of novel therapeutic strategies to treat colon cancer, particularly drug resistance.

Taking the swash plate piston pump as the research plant, the paper introduces the composition of digital control system of variable pump first; Then the mathematical model of variable mechanism is established according to which the closed-loop flow control system and the power control system are worked out. Also, the paper shows the stability margin of the control system and analyzes some response indices to step command under Matlab simulation. Aiming at the shortage of the closed-loop control system, the paper gives an idea of an optimization design of the compound power control system based on both feed-forward and feedback control. Compared with the conventional closed-loop power control method, the compound one gets a 47.2% reduction in the adjusting time and a 38.2% decrease in the overshoot indicating that the adjusting process is obviously shortened and the disturbance effect effectively weakened.

Real-time positioning of thin seam shearer's working position is an important prerequisite to achieve thin seam mining face automation control. Based on the analysis of walking mechanism of thin seam shearer and the existing shearer positioning systems, a method was proposed by detecting the shaft angle with the improved thin seam shearer angle encoder. Meanwhile shearer automatic calibration method was designed based on the magnetic sensor by adjusting the error coefficient. The system provides the data support of thin seam shearer automation control.

Aiming at full view field control problems of infrared thermal imager during Light stress reliability test,this paper designs a standard light source with wide view filed, makes infrared target and background achieve a quantitative and standardized output and provides an important basis for reliability test of infrared thermal imager,it is a kind of indemnification for improving the quality of thermal imager. In this paper, the background of light stress blackbody and the target of infrared target is designed to provide a standard light stress source for test, the design of parallel light pipe can provide a wide view field. Application of digital image processing technology achieves automatic monitoring during test and computer can control output on light stress background and target according to needs ,so this system is automated from image acquisition to data processing.

In order to satisfy the practical requirement, Durability test-bed for new developed hydraulic pump is designed which mainly includes design of hydraulic systems, design of data acquisition and processing system and design of test bench and electronic control system. According to application, it shows that the Durability test-bed is effective for durability test of new developed hydraulic pump and it can help to improve the design of hydraulic pump

Shearer cutting unit is the main working mechanism of the shearer and its performance is a direct reflection of the performance of the shearer. Three-dimensional solid model of shearer cutting unit mechanical system was built by 3D modeling software Pro/E, and then it was imported into ADAMS through a dedicated interface module. After adding constraints and movement driven and calibrating model, the simulation analysis in the ADAMS was established and analysis of the forces of the three key pin hinge point was achieved, which provided the basis for the shearer cutting unit mechanical system design.

The shield machine is a large complete sets of equipment used for underground tunnel excavation in the city construction,it has been widely used in the tunnel excavation. Cutter is one of the key components of shield machine. Different geological conditions and badly application environment make the cutter stress complex. German Herrenknecht S749 shield cutter as an example, using PRO/E software to establish the three-dimensional model, ANSYS Workbench module establishes the cutter corresponding finite element calculation model, the force characteristics of the cutter in working process were analyzed, obtained the cutter`s stress strain distribution. The research results can provide basic data for the wheel structure design and construction maintenance.

In this paper, a new type of hydraulic test bed is developed which can be used for performance testing of hydraulic valves, hydraulic motor and hydraulic pump. The composition structure diagram of hydraulic system, power supply system, and the signal flow diagram of data acquisition system were designed. The characteristics of the LabWindows/CVI development tools and the usage of Prodave MPI/IE 6 network communication tools were introduced, also the database storage and access technology in LabWindows/CVI environment. It was proved through the practical application that the test bed is reliable and has the merit of higher precision and automation level, and simple operation.

This paper studied the fine registration techniques of measuring data of complex product and proposed a new registration method based on triangle constraint. Firstly, the paper made a research on specifying the proper measuring reference points and the setting of reference coordinate system, and afterwards proposed a fine registration algorithm of measuring data, Which is about realizing the fusion of reference coordinate system based on the congruent judgment of reference triangle and fulfilling precise match of data with measuring error on the basis of controlling the rotation of data blocks and minimizing the registration error.

In order to ensure the performance of new products, a performance testing system including the design principle, design of hydraulic system and establishment of the computer data acquisition and processing system is given, which can be used to simulate the actual working conditions of a variety of hydraulic components and also used for the loading test. According to application, it shows that the performance testing system can work as an effective approach for quality checking for the new produced hydraulic components before they were put into the market.

As is known to all, new mechanical product design is always on the basis of the original product, so to better use the exiting design resource, a mechanical product variant design method is presented. The new method is based on SML and parameter CAD. According to different geological conditions of coal mine, different types of hydraulic support are needed to design. So as a typical kind of mechanical product, hydraulic support is given as an example to demonstrate the new variant design method. Finally with SOLIDWORKS as a specific application object, integrated with SQLServer2000 database, a hydraulic support variant design system is realized by Visual Basic program, which shortens the cycle of mechanical product development and reduces duplication mechanical design greatly.

The role, principle and characteristics of the rubber chain attached board used in steel wire knitting machine were analyzed in this paper. A new kind of attached board with reasonable structure was designed through comparison of several design schemes. Eventually, through finite element analysis and size optimization design based on Workbench, the structure size of attached board was optimized and the whole strain, the maximum equivalent stress and the minimum safety factor were calculated. At the same time, new design ideas are also provided for the development of steel wire knitting machine to save materials and reduce cost.

Hydraulic test platform is a very important testing tool for hydraulic products of engineering machinery. In this paper, a new type of hydraulic test bed is developed which can be used for performance testing of hydraulic valves, hydraulic motor and hydraulic pump. The composition structure diagram of hydraulic system, power supply system, and the signal flow diagram of data acquisition system were designed. The communication between sensors and computer via RS232 were researched. At last, the hydraulic test software is developed by using Labwindows/CVI and Simense PLC.

In this paper, an implementation framework of electromechanical equipment online management was put forward by studying on key technology of coal mine electromechanical equipment online management based on web. Based on ASP.NET technology, C# as development language, Oracle10g database for data processing, it realized cross-regional and inter-provinces multi-sector information online management, information sharing and report form processing, improved electromechanical equipment management efficiency of mine enterprises and reduced management costs.

Large centrifugal water pumps are widely applied in various water-supply and drainage systems. The vacuum-pumping is pre-requisite for their start-up so that the intelligent vacuum-pumping detection device utilizing STM32F103 as the main controller was presented to realize the automatic control especially of unattended pumps. A differential pressure transducer was adopted to measure the vacuum degree in pump chamber. Afterwards, an electrical signal of corresponding value was output, and then entered the ADC of STM32F103 after conditioning. The threshold algorithm was introduced for the judgement whether vacuum-pumping had been accomplished. Actual applications indicated this detection device was feasible and reliable, and the judgement algorithm was simply implemented and performed well in practice.

Based on the preprocessed measuring data, this paper proposes a method for identification and reconstruction of regular curves and surfaces including straight line(segment), circle(arc), four-sided plane and right cylindrical surface. Considering the geometric feature of each kind of regular curve or surface, the paper studies the corresponding algorithm for identifying the curve or surface point set, reconstructs the curve or surface and gives the parameter equation.

Bidirectional hydraulic lock is a key component of hydraulic system of the truck crane[1]. By using Fluent software, this paper simulates and analyses the hydraulic clamping phenomenon, which happens in the truck crane outrigger bidirectional hydraulic lock's spool in the case of taper exists, as well as the center lines of spool and valve sleeve are eccentric, and the effect of different kinds of pressure-equalizing grooves on hydraulic clamping force, then concludes that the number, the shape and the size of pressure-equalizing grooves, and whether pressure-equalizing grooves are concentric can take effect on clamping force, thus a new way is prompted to improve the structure of bidirectional hydraulic lock.

The fluid flows and its related aerodynamic noise are very common in the nature and the engineering fieds. Lattice Boltzmann Method (LBM), which is based on the mesoscopic models, is a new CFD approach. It has the congenital superiority and the inestimable development potential in the simulation of complex fluid flow. Referring to the experimental results provided by NASA/CP 2004-212954, the aerodynamic noise produced by the flow through a cavity is simulated by the lattice Boltzmann method. The results had vividly demonstrated the shear layer oscillations, the couple between the shear layer oscillations and cavity resonance pattern. This simulation has discovered that the shear layer oscillation is the main reason for the production of cavity aerodynamic noise. The simulation results are consistent with the NASA experiment data.

This paper discusses the hardware and software of polarization control system of the industrial circulating water. With the STM32 microprocessor produced by ST as its control core, this control system expands the display function of the zone LCD driving circuit which can realize field operation parameters, and designs the analogue acquisition circuit that can achieve the collection of circulating water polarization effect. The function of isolation output of the polarization energy can be achieved by the three-way PWM signal and the control signal produced by microprocessor, which can not only protect the output driver circuit effectively, but avoid the short circuit output. For the software design, the PID adjustment is adopted to realize the adjustment function of the output energy of PWM. The effect of energy saving and emission reduction of industrial circulating water can be attained in the later actual application.

The clinching process of magnesium alloys has a great potential of being high efficient joining method, but it is restricted by the limited formability of magnesium alloys at room temperature. To form acceptable joints without cracking, it is usually required to heat the parts to about 220°C. However, the pre-heating times of traditional forming method is more than 3 to 6 seconds, the application of clinching for magnesium alloys is restricted by the over long periods of heating time. A new joining process with a contoured die is introduced to offer great benefits, especially in pre-heating time. Then the heat transfer process is simulated with DEFORM-3D software. The results show that the pre-heating time reduced to less than 1 second. Thus it is efficient and reliable in joining of magnesium alloys parts.

Dent resistance of automobile panels becomes an important issue and quality criterion. In this paper, the dynamic dent resistance of automotive hood outer panel is analyzed by means of finite element method. The geometric model of automotive hood outer panel is firstly established by UG software. Then the finite element model of automotive hood outer panel is established in ANSYS. The dynamic dent resistance of automotive hood outer panel is analyzed by simulating the collision between a rigid ball and an automotive hood outer panel. The results show that compared with the traditional steel panel, the automotive hood outer panel made of aluminum alloy can reduce its weight by 36.3% while meeting the requirement of dynamic dent resistance. It is concluded that making automotive hood outer panel by aluminum alloy is feasible for automobile lightweight.

The application of MSComm widget has achieved serial communication of personal computer and sing-chip micyoco in distributed control system. This communication method has the characteristics of low cost, simple hardware connecting and software designing and convenient operation. It can fulfil the need of serial communication. The serial communication has some valuable reference for monitoring and control system in industry and data collection system.

Based on the dynamic balance principle and contact fatigue properties of cylindrical gear pair, the influence factors of dynamics are researched and the meshing location for the maximum contact stress is accurately determined. Loading spectrum of contact stress is obtained by transient dynamic analysis. At the same time, the corresponding S-N curve for contact fatigue is described in a double logarithmic coordinate system. Then the finite element analysis on the contact fatigue life is carried out by ANSYS Workbench and safety factor for both gears are obtained. It has great significance for evaluating the reliability of the cylindrical gear pair.

The utilization of magnesium alloy wheels is useful for automobile lightweight. A kind of magnesium alloy wheel was designed by using TRIZ theory, and then the three-dimensional CAD model was created using UG NX 7.0. According to these, the static structural analysis of the magnesium alloy wheel had been simulated with finite-element method. It can be shown that the high stress distributes mainly in the region of bolt holes and the transitional region between the rim and spokes of the wheel. The maximum stress is less than the yield stress of magnesium alloy. Some valuable references are provided for the design and development of magnesium alloy wheel.

In this paper, in view of the energy consumption problems of coal enterprises ,the overall technical framework of high efficiency and energy-saving for coal mines is proposed, and staged structure optimization model and network matching optimization model of mechatronic systems for coal mine are established ,which provide a theoretical basis for optimizations of mechatronic systems and promote the development of energy-saving technologies of coal mines.

This thesis makes in-depth study on product assembly costs in the theoretical basis of feature mappings and cost estimation method of concurrent design. It builds up a mathematical model of feature mapping from product design domain to assemble domain, proposes a prototype system framework of assembly cost estimation and also provides theoretical and technical support for design of product cost reduction.

This paper mainly has stress analysis on the structure of hydraulic support, the analysis results largely reflect the force characteristics of support. The method using the finite element can deal with the structure strength question that the conventional mechanical method can not deal with and makes the result more safe and reliable.

In view of the situation of shearing the scraper chain frequently and adjusting the pitch chain of the scraper conveyer in the coal mine, the project design a kind of hydraulic security shearing machine for the annulus chain of scraper conveyer, to solve the problem for high strength and heavy gauge annulus underground coal mine to cut off.

The successful matchings of the coal face equipments can fully play the effect of complete sets of equipments and achieve high yields and efficiency on coal faces .in this paper, ontology is used in the "three-machine"selection and matching knowledge modeling, which adopts the thought of combination on lateral and vertical modelings, and reuses the semantic body technology according to the characteristics of "three-machine" knowledge. As a result, the efficiency of ontology construction is improved largely and ontology structuration and standardization are strengthened. The ontology not only provides the exact knowledge representations, but also achieves knowledge reasoning and queries based on users to realize knowledge sharing and reusing. It provides a technical support for optimal matchings on" three-machine".

Drainage system is one of the important sub-systems of coal mine integrative control platform[1], and is used to guarantee the safety of mining and auxiliary transportation under the ground. The functions of drainage system are defined, the network framework is designed, the start and stop procedures of the pump engine under the manual control mode and automatic control mode are described, and the determining methods based on liquid level to control several pumps in automatic mode are analyzed. By using Simense PLC module, power source module, digital module, analog module and touch screen hardware, the drainage system control platform is set up, which is connected to the control computer on the ground by using Simense communication module and industrial ring Ethernet[4], and achieved the purpose of remote control.

Basing on the introduction of Multidisciplinary Design Optimization (MDO), Multidisciplinary Design Optimization method based on iSIGHT is given, which includes one general process model and one optimization algorithm. Optimization of one bearing is selected as one example. According to its application, it approves that MDO methods can solve practical engineering problems more effectively because of comprehensive consideration of the internal problems in all disciplines.

This thesis presents and summarizes the theory of multi-domain feature mapping in details and provides a basis of the conversion from design domain features to cost domain feature. It studies the current cost modeling techniques based on cost feature, and describes the whole process of cost feature modeling. This thesis lays a foundation for cost estimation.

Basing on the analysis of Mine Hoist working condition, Research on fault diagnosis system for Mine Hoist was introduced, including detailed introduction of its functions, composition and work principles. According to its application, it shows that fault diagnosis and monitoring technology to ensure that the equipment can run in good conditions so as to reduce unplanned downtime and help to reduce maintenance costs.

This paper mainly has carried on the analysis to the welding performance of high strength steel WH80, through the stretch and the bend test of manual welding rod, arc welding, the slanting y bevel weld crack test and the highest hardness test in welding heat-affected zone. It indicates that the WH80 steel has the good welding performance and is good material for hydraulic support.

The paper mainly analyses the vibration of air compressor house in colliery, chooses the reasonable vibration-resistance measures and solving schemes and realizes the design aim in phase. It ensures the nicety of decreasing vibration instrument, damped vibration instrument, the efficiency of vibration-resistance over 80% and vibration speed less than 12mm/s, which reduces the effect of vibration for the surroundings.

In this paper, based on virtual prototype Collaborative Development Platform for Hydraulic support, a new technology way to the design and study of the mining hydraulic support is provided.The function constitute of the platform which can support the whole multi-disciplinary collaborative development procedure of Hydraulic support are given. The Development of Hydraulic support based on virtual prototype Collaborative Development Platform is given, which includes the following key steps: Team member management modeling, Process management modeling and Co-simulation. The development of hydraulic support shows the effectiveness of the virtual prototype collaborative development for hydraulic support.

Based on the application analysis of hydraulic pump CAT test-bench, an automatic testing system of hydraulic pump CAT test-bench combined with technology of measurement and control was raised, including the detailed introduction of its work principle, components and software. By this testing system, tests of hydraulic pumps were realized automatically, accurately and efficiently.

This paper mainly analyses the force state for upper telescopie prop, down telescopie prop and cylinder of double-telescopie props for hydraulic supports. It builds up the mathematic model for accounting intensity of double-telescopie props, and presents the calculating method of accounting intensity for double-telescopie props.

Different with the traditional expert classification of building ontology, Web-platform folksonomy is used to analyze the tagging of mechanical components in the networked and collaborative environment. And according to the combination of tags of mechanical components and ontology technology, the ontology model is given based on one instance by protégé to reveal the information characteristics of mechanical components more realistically and more completely. With the trend of realization of manufacturing informationization, the mechanical components ontology provides a contribution to the communication, sharing and knowledge reusing of mechanical products.

Collaborative product development (CPD) is a dynamic collaborative process. A workflow model supporting CPD can provide a powerful and orderly workflow management for modern product development. This paper studies the requirements of CPD towards the workflow model, establishes a workflow metamodel supporting CPD process, proposes an idea of ontology-based workflow modeling and builds the workflow ontology model, which will strongly support interactive manipulation between the workflow management systems of collaborative product development.