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Distributed software systems often intertwine the handling of application functionalities with distribution related issues including location transparent access to services, workload allocation among different hosts, adaptation to changing conditions of the network. In the paper, a computational reflection based distributed query model is proposed. The model uses computational reflection to divide the distributed query system into two levels: the meta level and the base level. Meta objects that existed in the meta level are responsible for control and description of the base level, hence the state change of the base level could be captured by the meta level and be controlled according to the meta level’s reaction. The advantages of the model are that adapt different changes such as data resources in the network, network conditions, query plan, and provide the capability of fault tolerance.

The tide is a very important physical factor which can significantly affect the structure and evolution of stars. The physical factors which can affect tidal synchronization and orbital circularization are explored in this paper. For stars with radiative envelopes, radiative damping mechanism is required to explain the observed synchronization and circularization of close binaries. A star can experience a range of oscillations that arise from, and are driven by, the tidal field:the dynamical tides. The dynamical tide is the dynamical response to the tidal force exerted by the companion; it takes into account the elastic properties of the star, and the possibilities of resonances with its free modes of oscillation. The dissipation mechanism acting on this kind of tide is the deviation from adiabaticity of the forced oscillation, due to the radiative damping. Several physical factors can have an influence on the process of radiative damping which is scaled with thermal timescale. These physical factors include stellar mass, initial velocity, orbital period, metallicity, overshooting, etc. According to the equations for angular momentum transfer and chemical elements diffusion, we can obtain how these physical factors affect the evolution of rotating binaries and the mixing of chemical elements in two rotating components. The results indicates that the binaries with massive stars, smaller initial spin velocities, smaller overshooting parameters, and shorter orbital periods can attain the equilibrium speed and orbital circularization early. At synchronous states, the tidal torque is zero and stellar winds continue to brake the star. Therefore, two components cannot keep the synchronous state for a long time. At the equilibrium state, the tidal torque is counteracted by wind torques. Therefore, the equilibrium speed is less than the synchronous one. The system with smaller initial spin velocities reaches the equilibrium speed and orbital circularization early because angular momentum transformation between spin and the orbit can shorten the orbital distance and increase the tidal torques. Nitrogen enrichment in binaries is weaker than the one in single stars due to tidal braking. The results reveal that the system with massive components, higher metallicities, larger overshooting parameters, and shorter orbital periods can display high nitrogen enrichment. Stellar radius is small in the star with lower mass, lower metallicities, slower spin speeds and larger overshooting parameters whereas the star with lower metallicities have higher surface effective temperature. Rapid rotating stars evolve towards low temperature and luminosity in the HR diagram.

The aim of this study was to ascertain the relationship between the phosphorylation of FOXO1 and the apoptosis and the proliferation of lymphoma cells so as to further clarify the cellular biology and pathogenesis of the disease. The lymphoma cells Namalwa and Jurkat were treated with PI3K inhibitor wortmannin or etoposide alone or wortmannin plus etoposide with different schedule. The inhibition rates of lymphoma cell growth were examined by XTT assay. Apoptosis were detected by flow cytometry. The expression of p-Akt, p-FOXO1, FOXO1, bim were determined by western blot analysis. Wortmannin induced apoptosis of Jurkat cells and Namalwa cells and inhibited their survival effectively. The rate of growth inhibition and apoptosis of lymphoma cells induced by wortmannin plus etoposide were higher than those induced by etoposide alone. After treated with wortmannin, phosphorylation of FOXO1 remarkably reduced and bim increased. The dephosphorylation of FOXO1 inhibited proliferation of Jurkat cells and Namalwa cells, promoted their apoptosis and sensitized Non-Hodgkin lymphoma cells to etoposide. Bim activated by FOXO1 promoted cells apoptosis.

The recovery of motor function in rats is inhibited following contusion spinal cord injury (cSCI). However, the mechanism of tumour necrosis factor α (TNF-α) in motor function after cSCI associated with peroxiredoxin 6 (PRDX6) remains unknown. We randomly divided rats into four groups: sham, cSCI, vector and lentivirus mediating TNF-α RNA interference (TNF-α-RNAi-LV) group. The Basso, Beattie, Bresnahan (BBB) scale was used to evaluate motor function. Real-time quantitative PCR (qRT-PCR) and western blotting were used to detect the expression of TNF-α and PRDX6, which were located in neurons using immunohistochemistry (IHC) and immunofluorescence. Subsequently, lentiviral-mediated TNF-α was used to determine the role of TNF-αand the relationship of PRDX6 and TNF-α in cSCI. After cSCI, the motor capability of hind limbs disappeared and was followed by recovery of function. IHC analysis indicated that TNF-α and PRDX6 were primarily located in spinal cord neurons. TNF-α interference significantly improved neural behaviour and increased expression of PRDX6. Our study suggests that inhibition of TNF-α can promote the recovery of motor function. The underlying mechanism of TNF-α-promoted motor function may be connected with the up-regulation of PRDX6. This provides a new strategy or target for the clinical treatment of SCI in future.

Synaptosomal-associated protein 25 kDa (SNAP-25) is localized on the synapse and participates in exocytosis and neurotransmitter release. Decreased expression of SNAP-25 is associated with Alzheimer's disease and attention deficit/hyperactivity disorder. However, the expression of SNAP-25 in spinal cord contusion injury is still unclear. We hypothesized that SNAP-25 is associated with sensory and locomotor functions after spinal cord injury. We established rat models of spinal cord contusion injury to detect gene changes with a gene array. A decreased level of SNAP-25 was detected by quantitative real time-polymerase chain reaction and western blot assay at 1, 3, 7, 14 and 28 days post injury. SNAP-25 was localized in the cytoplasm of neurons of the anterior and posterior horns, which are involved in locomotor and sensory functions. Our data suggest that reduced levels of SNAP-25 are associated with sensory and locomotor functions in rats with spinal cord contusion injury.

To compare the clinical efficacy in the treatment of post-stroke shoulder-hand syndrome between floating-needle therapy and conventional acupuncture on the basis of rehabilitation training.One hundred cases of post-stroke shoulder-hand syndrome were randomized into a floating-needle group and an acupuncture group, 50 cases in each one. The passive and positive rehabilitation training was adopted in the two groups. Additionally, in the floating-needle group, the floating-needle therapy was used. The needle was inserted at the site 5 to 10 cm away from myofasical trigger point (MTrP), manipulated and scattered subcutaneously, for 2 min continuously. In the acupuncture group, the conventional acupuncture was applied at Jianqian (EX-UE), Jianyu (LI 15), Jianliao (TE 14), etc. The treatment was given once every two days, 3 times a week, and 14 days of treatment were required. The shoulder hand syndrome scale (SHSS), the short form McGill pain scale (SF-MPQ) and the modified Fugl-Meyer motor function scale (FMA) were used to evaluate the damage severity, pain and motor function of the upper limbs before and after treatment in the two groups. The clinical efficacy was compared between the two groups.SHSS score, SF-MPQ score and FMA score were improved significantly after treatment in the two groups (all P0.01), and the improvements in the floating-needle group were superior to those in the acupuncture group (all P0.05). The total effective rate was 94.0% (47/50) in the floating-needle group, which was better than 90.0% (45/50) in the acupuncture group (P0.05).The floating-needle therapy combined with rehabilitation training achieves a satisfactory efficacy on post-stroke shoulder-hand syndrome, which is better than the combined therapy of conventional acupuncture and rehabilitation training.

A boundary-element method with a quadratic time interpolation technique is developed for transient eddy-current problems. A time-domain discretization element and its integral formulations are presented. Two examples are given and compared with previous solutions to demonstrate that the proposed technique has the important advantage that a larger time step can be used. >

A novel algorithm for computing optimal constrained triangulation is presented which is equally applicable to 2-D and 3-D optimal constrained triangulation and Delaunay triangulation. This algorithm has no degenerate and near-degenerate problems. The same amount of time is needed to add a new point to an existing mesh of any element number provided that the element it belongs to has been predetermined, as in the self-adaptive finite-element analysis process. This algorithm has been applied to finite-element mesh generation. Test results are given. >

Rotation and tide are two important factors which have an influence on the stellar structure and evolution. They cannot be neglected. According to the observation data of the massive binary system V478 Cyg, we test the theoretical model including the deformation which is induced by rotation and tide (our model). We compare our model with Kähler-Eggleton (KE) model, and the distorted model is more consistent with observations than the traditional model (KE model). Besides, it is found that great deformation occurs in the outer envelope, where its density is lower than the mean density. Rotation and tide can cause the gravity at the two polar points to increase and the gravity in the equatorial plane to decrease. Therefore, the radiative flux, which depends on the local effective gravity, is not constant on the equipotentials any more. The poles which become hotter, experience a high mass loss than the equator, which becomes cooler. Furthermore, the two components in our model have bigger radii, equatorial velocities and central compactness and low H-energy production rate. The bigger mean radius of the distorted star produces a smaller temperature gradient inside the star, resulting in a lower energy transport. The lower energy generation rate inside the distorted model will widen the main sequence and increase the stellar lifetime. Stellar temperature and luminosity of the distorted model are shifted toward lower value. The tidal distortion inside the secondary star plays a most important role in the rate of the apsidal motion because of lower compactness. The apsidal motion derived from rotation is larger than the one derived from the general relativity.

A high-performance fully-digital controller has been designed for the drive of a 50 kW 4-phase switched reluctance (SR) motor built for hybrid electric vehicle (HEV). The SR machine is specifically designed and manufactured to have high power density and low acoustic noise. The controller is based on the advanced digital signal processor (DSP) with internal CAN interface-TMS320F2406 and complex programmable logic device (CPLD)-EPM7128S. The DSP mainly performs several tasks: A/D conversion, new control strategies such as directly average torque control and development of control algorithm, fully-digital hysteretic current-loop, generation electricity control and communication among all vehicle peripherals. The CPLD integrates all periphery logic circuit with responsibility for handling of position signal and intelligent over-current protect. High voltage, large capacity IGBT module and IGBT drive module with fibre-optic interface are adopted. A custom-made rotary position sensor has high reliability. The experimental results show that the controller is met with the system specification and requirement, satisfactorily.

In order to improve the performance of switched reluctance motor (SRM) drives, some advanced control strategies have been proposed, such as current or flux linkage profile control. To achieve these strategies the motor phase current or phase flux linkage should be controlled precisely. All these require increasing the switching frequency of converter to upgrade stability and dynamic response speed. However, the higher switching frequency may cause the higher switching losses, higher electro-magnetic interference (EMI) and the lower overall efficiency. The use of soft-switching techniques in converter can contribute to reduce them. In this paper a novel soft-switching converter for SRM is presented, which possesses advantages of resonant switch converter (RS), resonant DC link converter (RDCL) and PWM. The addition of external commutating devices to conventional asymmetric bridge converter for SRM substantially reduces switching losses and EMI. The conditions of soft switching are deduced and a practical design consideration is given. Finally, detailed simulation study of the complete system is presented and validated with experimental results

Due to the inherent advantages, such as simple structure, ability to operate in harsh environments, fault-tolerant and four-quadrant operation, and wide speed range with high power density and high efficiency, switched reluctance motor drives (SRD) becomes a strong competitor in electric vehicle application. In vehicle propulsion the vehicle control unit expects a precise and stationary average torque of the electric drive which tracks precisely the reference torque to perform vehicle dynamic control. In this paper, a novel control strategy is presented to achieve closed-loop torque control for SRD more accurately at varying load and changing electrical input condition. Additionally, a novel method for real-time measurement of flux linkage is presented, and simulation and experimental studies have been done. Finally, the feasibility of the torque control strategy is validated with performance test of the proposed system.

High reliability, wide speed range capability, as well as competitive weight and efficiency combine to make the switched reluctance machine (SRM) a strong candidate for electric vehicle (EV) and hybrid electric vehicle (HEV) propulsion systems. A rated output power 50 kW, peak power 100 kW switched reluctance machine drive has been developed for a HEV passenger bus propulsion system. An improved 2-D finite element method (IFEM), in which the fringe flux at the ends of the core is counted, is introduced. In this paper the design of the SRM is described in detail. Specifications, IFEM analysis, simulation as well as experimental results are also presented.

Aiming at the nonlinear characteristics of a switched reluctance motor (SRM), this paper describes a sample method to estimate the parameters for a PI speed controller while the SRM works in current chop control (CCC) mode. Firstly, based on the linear and nonlinear mathematical model of SRM, some simple background is given. Then, the control schematic is built and some simulation work is done on the MATLAB system. With this simulation, we obtained the parameters for the PI speed controller. The parameters that are obtained from simulation work have been applied to a 50 kW SRD system. The experimental result indicates that it is feasible to use this method to estimate the parameters for SRM. It also shows that this method can greatly reduce the work of debugging and programming.