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Strawberry fruit easily suffers from fruit disease caused by fungus infection because of its great susceptibility to microbial spoilage. In present paper the fungus pathogen was isolated from infected strawberry fruits. The molecular method was used to identify the species of the fungus. The internal transcribed spacer (ITS) region was amplified by PCR with the pair of ITS universal primers after extracting the genomic DNA from the isolate. The sequence alignment results indicated that the identity was 95% between the strain F1 and the fungus(GenBank: FN667943). Then the phylogenetic tree was constructed based on the sequence of ITS region of the fungal rRNA operon. According to the sequences of ribosomal DNA-ITS and phylogenetic analysis, the fungi was preliminaryly identified as Trichocomaceae. So the pathogen isolated from the infected strawberry fruits in Tianyi strawberry ecology located in Changping district, Beijing, China is a species of Trichocomaceae.

In order to explore the effects of bacteriocin treatment on storage and quality of postharvest strawberry fruit, the inhibitory effects of a bacteriocin, produced by Lactobacillus plantarum, against rhizopus on infected strawberry fruits, was evaluated. Meanwhile, corruption rate, total soluble solids (TSS), total titratable acidity (TA) and vitamin C content were analyzed comparing between bacteriocin LF-1 and nisin treatment. The results show that the bacteriocin LF-1 has a significant inhibitory effect against spore germination of rhizopus. The average spore germinations of rhizopus was only 15.5% when treating with bacteriocin LF-1 at volume percentage of 20%. Freshly harvested strawberries were placed in room temperature and aspersed with bacteriocin LF-1 and nisin for 6 days. In particular, corruption rate, TSS, TA and vitamin C content were respectively 40%, 4.0mg/100g, 60.3% and 63.0mg/100g with bacteriocin LF-1 treating. These data suggest that bacteriocin LF-1 significantly reduced fruit decay and maintained overall quality, thereby extended the shelf-life of the strawberries.

The purpose of this study was to investigate whether hemoglobin-based oxygen carrier (HBOC) could protect the heart from intense exercise-induced myocardial dysfunction. Adult male Sprague-Dawley rats were subjected to 5-h intense prolonged running on treadmill with or without HBOC pre-treatment. Immediately after exercise, the heart rate (HR) and oxygen delivery capacity of the blood were measured. After 1 h of rest, echocardiography was performed to assess the post-exercise cardiac function. Then all the hearts were isolated and perfused using the Langendorff model for 1 h. Our results proved that pronged exercise caused significant LV dysfunction, while HBOC pre-treatment attenuated such a damage, as evidenced by the increased oxygen delivery, cardiac fractional shortening (FS), rate-pressure product (RPP), ±dp/dt and coronary flow rate (CF) and decreased myocardial necrosis. The releases of cardiac enzymes, including creatine kinase-MB (CK-MB) and cardiac troponin-I (cTnI) were markedly reduced. No significant difference of cardiac infarct size was observed among groups. In addition, HBOC significantly elevated superoxide dismutase (SOD) activity and decreased hydrogen peroxide (H 2 O 2 ) formation, which indicated the exercise-induced cardiac oxidative damage was inhibited. In conclusion, HBOC pre-treatment showed a promising cardioprotective effect on prolonged exercise-induced cardiac dysfunction, which was probably associated with its ability to decrease myocardium oxidative stress.

In this paper, we present the modeling and kinematics simulation of a six-DOF segment erector for tunnel boring machine (TBM), which is performed in the virtual prototype platform. The 3D virtual assembling model of a tunnel segment erector is built based on Pro/E software according to its design parameters such as structure and size. After the interference inspection, the model is imported into ADAMS through the interface module of Mech/Pro. The model is simplified and optimized reasonably and various constraints are applied under variety working conditions. The results of simulation show that the design has six degrees of freedom movement capacity which meets the design requirements. At the same time the kinematics characteristics of each part along three different directions are obtained and they will provide some references for the further optimal design.

The rock breakage process is the interaction process between TBM and rock mass, which is affected by TBM specifications, such as thrust force, cutter tip width and profile, cutter spacing, RPM, and torque, and rock mass properties mainly including rock material strength, rock brittleness, joint spacing and orientation. In this study, based on the systematic study of the existed rock constitutive model achievements and introduction of rock breaking mechanism, main failure mode of rock in the breaking process of disc cutter is added and revised in order to meet the actual situation. The method of establishing finite element model of disc cutter breaking process using ANSYS AUTODYN-3D software is introduced. After the dynamic simulation, we can obtain that geotechnical interface disturbance insulted by disc cutter. Based on plenty of experiments, it confirms reliability of numerical methods and provides a method to study cutting performance for different geological conditions.

An e-cient and stable hybrid method, based on the time-domain integral equation (TDIE) and time-domain physical optics (TDPO), is developed for investigating transient radiation and scattering from perfectly electrical conducting (PEC) objects. It at flrst requires partitioning the PEC object surface into TDIE and TDPO regions, respectively. Then, a set of hybrid TDIE-TDPO equations is derived and solved using an adaptive marching-on-in- degree (MOD) method. The fast Fourier transforms (FFT)-based blocking scheme is further implemented into the proposed algorithm so as to reduce N 2 O dependence of the traditional MOD method to NO log 2 (NO), where NO is the highest order of the weighted Laguerre polynomials used for computation. Under such circumstances, its computational cost, in comparison with the full TDIE-MOD solver, is reduced signiflcantly. Several numerical examples are presented to demonstrate its accuracy and e-ciency in solving some typical transient electromagnetic problems.

The α-bromination reaction of arylacenones with 1,2-dipyridiniumditribromide-ethane (DPTBE) as brominating agent under solvent-free condition, selectively gave the corresponding α-bromoarylacenones derivatives with a simple procedure and excellent yields.

This study was to investigate whether polymerized human placenta hemoglobin (PolyPHb) given before ischemia protects in vivo rat heart function against ischemia/reperfusion (I/R) injury. Forty-five male Sprague-Dawley rats were randomly divided (n = 15 per group) into a sham group, control group (pretreatment with Lactated Ringer's solution), or PolyPHb group (pretreatment with 0.1 gHb/kg PolyPHb). Rat hearts were subjected to 30-min ischemia by occlusion of left anterior descending, followed by 2-hr reperfusion. As compared to the control group, PolyPHb preserved cardiac function and reduced cardiac troponin-I release and histopathological changes. Therefore, PolyPHb pretreatment provided a profound cardioprotective effect on the in vivo rat heart.

Development of EV is an important means which optimize chinese energy supply structure and break security strategy of energy.As the state increasing subsidy strength and constructing large-scale charging infrastructure for EV,EV is expected to become an important means of transport,and in the future EV is becoming to an important mobile storage unit in smart grid, playing the dual role of energy comsume and energy storage. Combination of domestic charging infrastructure and charge mode, discuss the charge and discharging and sale of electric technology for EV, which provide some reference for business model of the charging infrastructure,proposed to help the orderly charging and discharging for EV, realize win-win situation for power grid and the user.

The tendency of future communication network is to set up an environment supporting network convergence as well as dynamic service collaboration. The recent Internet of Things (IoT) visions makes provision of User-Centric and active service to common users an important aim. Service-Oriented Architecture (SOA) based on Web service technology works well for provision of request/response style passive service. However, services and devices in IoT or mobile environment may dynamically interact and cause a considerable amount of states changes, which calls for an active and more flexible framework to enable interactive service provision. In this paper we propose an Event-driven SOA based service integration framework (EDSIF) for provision of active service. Compared with traditional SOA based service provision method, this approach will facilitate real-time event processing as well as intelligent service coordination. We present the concept model of Event-driven SOA and the key components of EDSIF. We also illustrate the ECA4IoS rules for active service execution and the enhancement work of WSN broker towards an effective EDSIF.

The energy supply infrastructures construction is the prerequisite and basis for the large-scale promotion and application of electric vehicles (EVs). The characteristics and current construction situation of several EV power supply infrastructures in China such as AC charging spot, charging station and battery swap station are introduced first, and the characteristics of time combination mode and space combination mode for the construction of EV charging facilities are also discussed. Meanwhile, the features of operation mode for EV power supply infrastructures in different developing stage of are analyzed, and the main bodies for EV power supply infrastructures construction are also introduced.

Objective: We introduced a new atrial septum remodeling technique and further investigated the feasibility of this method in facilitating the intra-operative device closure (IODC) of multiple atrial septal defects (ASDs). Methods: Adult patients with multiple nearby ASDs, which were not eligible for transcatheter closure, were enrolled in this study. Transesophageal echocardiogram (TEE) was applied for intra-operative evaluation. The multiple ASDs were divided into three different types according to its morphology. Based on the concept of breaking the rim between multiple ASDs and making it feasible for single device closure, atrial septum remodeling procedure was carried out via pre-atrial approach using special clamp under the guidance of TEE. IODC was then attempted for reshaped ASD. Successful rate and perioperative complications were then noted. Results: Eleven patients were enrolled in this study, with mean age being 23.4 5.3 years and mean weight 51.6 8.0 kg. Among them, seven patients have double ASDs and four have triple ASDs. Mean diameter of isolated ASD was 10.4 3.8 mm with a mean distance of 3.2 1.2 mm between each other. Atrial septum remodeling procedure was successfully done in all patients. One device was then used for each patient. Mean ASD diameter after remodeling procedure was 20.6 3.9 mm with mean device size 23.5 4.0 mm. Complete closure of multiple ASDs was achieved in nine patients immediately after the procedure; two patients had trivial grade shunt after device deployment that resolved within the 3-month follow-up. No severe complications were noticed during the perioperative period and the 3-month follow-up. Conclusions: Atrial septum remodeling technique seems to be a safe and effective method that could largely facilitate the successful IODC of multiple ASDs. # 2011 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

Cutting processes of single abrasive grain were simulated respectively by fluid-solid interaction method and Smoothed Particle Hydrodynamics method. Advantages and disadvantages of the two methods were compared. Smoothed Particle Hydrodynamics method is superior to fluid-solid interaction method in simulating the deformation behavior of workpiece material for the motion of SPH particles. According to the simulation results, it is concluded that workpiece material occurs plastic deformation, flows to the side and front owing to the extrusion of abrasive grain, and finally forms chip in front of abrasive grain.

The key problems faced in developing indwelling catheters are how to incorporate antibacterial agents into the substrate and how to improve the antibacterial effectiveness. In this study, an antibacterial composite coating layer is inversely in situ formed on the silicone substrate by a novel technique involving deposition of an antibacterial agent, solution casting and crosslinking of a silicone resin. The antibacterial particles were strongly bonded to the matrix silicone and evenly dispersed on the coating surface. Moreover, energy-dispersive X-ray analysis revealed the gradient distribution of the antibacterial agent, perpendicular to the composite surface. The co-instantaneous crosslinking within the coating layer and polymer substrate as well as the graded structure formed lead to good adhesion between the two parts. The silicone composite shows a highly efficient antibacterial activity with no cytotoxicity to HL-60 cells. Compared with the commonly used methods of incorporating antibacterial agents into the silicone substrate, such as multiple dip-coating, surface grafting or simple blending, the proposed process is easily operated and is promising for forming a percutaneous or subcutaneous device with the capacity for efficient sterilization in an economical way. Copyright © 2011 Society of Chemical Industry

The mathematic models describing various joints of whole machine are founded to research dynamic performance of turn-milling center based on rigid-flexible coupling system. The various joint interfaces including the conical and cylinder contact, plane contact and fixed connection are regarded as flexible joints by using the spring and damping unit and the equivalent dynamic models of joint interfaces are built by finite element method based on different connection modes. Therefore, these mathematic models are used as references and foundations for research on dynamic performance of turn-milling center next stage.

In order to analyze accurately the dynamic characteristics of Linear Rolling Guide during the design stage, the Linear Rolling Guide that springs and damping units imitate joints is simulated by finite element methods in this paper. The proposed method can predict the regular pattern which joint stiffness and joint span affect natural frequency and harmonic response. The research demonstrates that the method predicts well the dynamic characteristics of the Linear Rolling Guide; therefore, it can be a reference for dynamic optimization design of Linear Rolling Guide in turn-milling center.

Cutting process of single abrasive grain was simulated by Smoothed Particle Hydrodynamics and Finite Element Method. Chip mechanism of single abrasive grain was analyzed according to the stress variation of grain and workpiece material, and motion situation of smoothed particles in cutting layer. Effects of abrasive grain rake angle and cutting depth on cutting deformation of workpiece material were also analyzed. It is concluded that workpiece material occurs to plastic deformation, flows to the side and front owing to the extrusion of abrasive grain, and finally forms chip in front of abrasive grain; cutting capability increases with the increase of abrasive grain rake angle, it results in the increase of material protrusion in front of abrasive rain and relatively decrease of material protrusion beside abrasive grain; workpiece material deformation and cutting force increase with the increase of cutting depth. Scratching experiment of abrasive grains was carried out by using vitrified bonded CBN block. It is found that deformation laws of workpiece material in the simulation and experiment are consistent. It is proved that the simulation results are correct, and the simulation method is feasible

An efficient integration scheme is proposed for calculating weakly singular and near-singular potential integrals over planar triangles, with an essential improvement over the original polar integration. The reason for the problem of slow convergence of polar integration is revealed according to some careful investigations. A new technique of smoothing integrand based on variable transformation is presented to guarantee the smoothness of the integral kernel, which results in much faster convergence than that of the polar integration. Some numerical results are given to demonstrate the capability of our proposed scheme for achieving high accuracy as well as rapid convergence rate in several numerical experiments.

To obtain the reasonable layout and structure shapes of the various kinds of cutters in tunnel boring machine (TBM), the kinematic/dynamic of cutter head system was analyzed by using virtual prototype and finite element method (FEM). The velocity and force curves were got from different positions of cutters and the mode vibration of scrapers and cutter hobs were obtained to analyze their structural performances next stage. It is shown that these results can provide references for dynamic optimization design of tunnel boring machine. Therefore, it is necessary to implement kinematic/dynamic analysis and mode analysis before manufacture of production.

An e-cient hybrid method, based on time-domain integral equation (TDIE) and time-domain physical optics (TDPO), is proposed for studying on transient electromagnetic responses of some wire and surface structures illuminated by an electromagnetic pulse (EMP), respectively. Two groups of triangular-type basis functions are used to expand the currents on both of them. The derived

Cardiac myxoma arising form right ventricular outflow tract (RVOT) is extremely rare, but could cause major clinical sequelae and pose considerable diagnostic and therapeutic challenges. Here, we report the intraoperative application of real time three-dimensional transesophageal echocardiography (RT3DTEE) in the assessment of a patient with a RVOT myxoma. RT3DTEE clearly assess the characteristics of the mass, such as the size, shape, attachment points, and composition. With the intraoperative guidance of RT3DTEE, the patient underwent successful removal of the mass.

In order to analyze the motion characteristics of turn-milling center, it’s prototype is modeled and spiral motion is simulated and analyzed to get curves of displacement and velocity in forward kinematics and inverse kinematics. The rationality and applicability of mechanism design is verificated to provide the basis of fast optimized design of turn-milling center. So the method can forecast and improve before physical prototype manufacturing to ensure design feasibility and save development time.

Transesophageal echocardiogram (TEE) guided perventricular cardiac intervention has gained popularity in recent years. We present a special case of perventricular closure conducted for a traumatic apical muscular ventricular septal defect (mVSD) under the guidance of three-dimensional (3D) TEE with an Amplatzer mVSD occluder and further discuss the important role of 3D TEE in perventricular cardiac intervention.

Introduction: Numerous newer parameters have been established for sensitive and reproducible evaluation of left ventricular (LV) dysfunction. We assessed the performance of these parameters in sequential monitoring of LV function in an animal model of controllable drug-induced LV dysfunction. Methods: To establish predictable aggravating LV dysfunction, seven male beagle dogs were anesthetized and received intermittent injection of esmolol and propofol of gradually increasing dosage. Parameters reflecting LV function were measured after each drug infusion. These included LV ejection fraction (LVEF) measured by both two-dimensional (2D) and three-dimensional (3D) echocardiography, Tei index, ratio of early diastolic transmitral flow velocity to early diastolic mitral annular velocity (E/e′) and 2D strain-derived parameters. Changes in these parameters over time were compared with the baseline value. Results: Changes in 2D and 3D LVEF were observed after infusion with propofol (5 mg/kg) and esmolol (3.5 mg/kg). Doppler-derived parameters including E/e′ and the Tei index failed to detect LV dysfunction prior to 2D LVEF. Significant changes in 2D strains and strain rates (SRs) could be induced by relatively small anesthetic dosages (∼4 mg propofol/kg and 2.5 mg esmolol/kg). Strain-derived parameters were generally highly reproducible and longitudinal strain had the best intraobserver and interobserver reproducibility. Conclusions: The 2D strain parameters provide accurate identification of subclinical impairment of LV function earlier than all other echocardiographic indices. (Echocardiography 2010;27:1274-1281)

To bridge quasi-geostrophic dynamics and its discrete representation by a series of piecewise constant potential vorticity (PV), the dispersion relation for the Rossby wave in the single-layer β-plane is compared with that for the normal mode of edge waves straddling an infinite series of PV discontinuities (‘PV staircase’). It is shown that the edge waves over evenly spaced, uniform-height PV steps converge to the Rossby wave on the β-plane as Δ → 0, L → 0, Δ/L = βeff (Δ, L and βeff are the step size, step separation and the effective β, respectively), whereas they reduce to the single-step edge wave in the short-wave limit. For sufficiently small step separations, the difference in the phase velocities of the edge wave and the Rossby wave scales as O(L2). Two effects of increasing L on the zonal propagation are identified: (i) increased phase and group velocities in the short-wave limit due to an increased zonal wind at the PV steps and (ii) decreased phase and group velocities in the long-wave limit due to a decreased effective meridional tilt of the mode. The reduced tilt also severely limits the meridional group propagation. The relationship between the edge wave mode and the finite-difference approximation to the Rossby wave is also discussed.

An exact diagnostic formalism for finite-amplitude eddy–mean flow interaction is developed for barotropic and quasigeostrophic baroclinic flows on the beta plane. Based on the advection–diffusion–reaction equation for potential vorticity (PV), the formalism quantifies both advective and diffusive contributions to the mean flow modification by eddies, of which the latter is the focus of the present article. The present theory adopts a hybrid Eulerian–Lagrangian-mean description of the flow and defines finite-amplitude wave activity in terms of the areal displacement of PV contours from zonal symmetry. Unlike previous formalisms, wave activity is readily calculable from data and the local Eliassen–Palm relation does not involve cubic or higher-order terms in eddy amplitude. This leads to a natural finite-amplitude extension to the local nonacceleration theorem, as well as the global stability theorems, in the inviscid and unforced limit. The formalism incorporates mixing with effective diffusivity of PV, and the diffusive flux of PV is shown to be a sink of wave activity. The relationship between the advective and diffusive fluxes of PV and its implications for parameterization are discussed in the context of wave activity budget. If all momentum associated with wave activity were returned to the zonal-mean flow, a balanced eddy-free flow would ensue. It is shown that this hypothetical flow uREF is unaffected by the advective PV flux and is driven solely by the diffusive PV flux and forcing. For this reason, uREF, rather than the zonal-mean flow, is proposed as a diagnostic for the diffusive mean-flow modification. The formalism is applied to a freely decaying beta-plane turbulence to evaluate the contribution of the diffusive PV flux to the jet formation.

Formation of multiple jets in forced beta-plane turbulence is studied from the perspective of nonuniform nonconservative arrangement of potential vorticity (PV). Numerical simulations are analyzed to show that mixing and forcing reinforce jets by concentrating PV gradients at the axes of prograde jets. Based on the formalism developed in the companion paper, the nonconservative driving of jets is diagnosed and parameterized through the diffusive flux of PV and the source of wave activity. It is found that the two terms nearly balance on a long time scale, and they are both strongly anticorrelated with the PV gradient, which suggests that PV controls the nonconservative processes and that these processes could be parameterized as functions of the PV gradient. The flux is modeled using the effective diffusivity formula recently obtained by Ferrari and Nikurashin. Consistent with the PV barrier concept, the nonlinear diffusivity is a decreasing function of the squared PV gradient and agrees well with the diffusivity diagnosed from the numerical simulation. The source term is assumed to be inversely proportional to the PV gradient. The parameterization gives rise to a nonlinear partial differential equation (PDE) for the mean flow. A finite-difference model of the PDE predicts formation of a piecewise linear PV (staircase) and piecewise parabolic jets from a near-uniform initial condition when anisotropy and mixing of the flow are sufficiently strong. The origin of the discontinuities is antidiffusive instability of PV gradients, and although nonlinearity allows the discrete model to integrate stably, the solution is sensitive to the initial condition and resolution. The emerging jets in the 1D model have similar characteristics to those in the numerical simulation, but the details of the transient behavior are distinct. Similar discrete models of ill-posed PDEs in which discontinuities form also appear in image processing and granular matter dynamics.

A sulfur-assisted and 1,8-diazabicyclo-[5.4.0]undec-7-ene (DBU)-catalyzed cyclization of 2-alkynylanilines for the metal-free synthesis of indole derivatives is reported. As a result of the metal-free process, the ready availability of the starting materials and the simple and convenient operation, the type of reaction presented here has potential utility in organic synthesis. A 10-gram scale preparation may demonstrate the possibility of its application in the environmentally friendly synthesis of indole derivatives.

We numerically investigate the motion of a charged particle in a planetary magnetosphere using several kinds of equatorial plane phase portraits determined by two dynamical parameters: the charge-to-mass ratio and the z-component of the angular momentum. The dependence of chaos on any of the three factors including the two parameters and the energy is mainly discussed. It is found that increasing the energy or the absolute value of the ratio always causes the extent of chaos. However, chaos is weaker for larger angular momentum. Qualitative interpretations to the results obtained are also given.

The Hongshan societies of northeastern China are among East Asia’s earliest complex societies. They have been known largely from elaborate burials with carved jades in ceremonial platforms. The most monumental remains are concentrated in a “core zone” in western Liaoning province. Residential remains are less well known and most investigations of them have been in peripheral regions outside the core zone. Recent regional settlement pattern research around the well known ceremonial site of Dongshanzui has begun to document the communities that built and used Hongshan core zone monuments and to assess their developmental dynamics. The core zone, like the Hongshan periphery, appears to have been organized into a series of small chiefly districts within which ceremonial activities were important integrative forces. Their estimated populations of less than 1,000 are not much larger than those of districts in the periphery, and the evidence does not suggest that these districts were integrated into any larger political entity. The greater elaboration of core zone monumental architecture is thus not attributable to demographically larger communities or to larger-scale political integration. Future research should focus on documenting the organization of statuses and economic activities within these core zone communities to assess potential differences from peripheral communities in these regards.

Aiming at the characteristics of structure and control of three-links hybrid machine tool, the interpolation strategy of CNC system is proposed in this paper. Coarse interpolation in workspace and fine interpolation in joint-space are expatiated. The trajectory points are transformed into discrete points by coarse interpolation mapping from workspace to joint-space. At the same time, the plans of trajectory, velocity and acceleration of discrete points in workspace are got, and then joint discrete points are realized by joint fitting smooth function. In order to meet the design demand and enhance effectively interpolation precision, the five polynomial interpolations will be thinning discrete points, and geometric locus will be very smooth.

Intelligent compression is important to image transmission in real time over bandlimited channels for synthetic aperture radar (SAR) payloads deployed on unmanned aerial vehicles (UAV), where target areas are encoded with high fldelity, while background data are encoded with lesser fldelity. A target-aided SAR image intelligent compression (TAIC) system is presented in this paper, which utilizes robust flxed-rate trellis-coded quantization (FRTCQ) to encode target sequences and FRTCQ to encode background sequences. Multiresolution constant false alarm rate (CFAR) detector in wavelet domain using db4 based on the multiscale model of target is embedded. Generic region of interest (ROI) mask is created. In order to achieve better quality of target areas decoded, ROI mask is modifled. The improved performance using TAIC system by compressing target chips from training set and testing set in Moving and Stationary Target Acquisition and Recognition (MSTAR) database is demonstrated.

An adaptive marching-on-in-order (MOO) method with FFT-based blocking scheme is proposed to solve the time-domain electric field integral equation (TD-EFIE) for conductive objects, with the temporal basis of Laguerre polynomials (LP) employed. In contrast to most MOO approaches that utilize a priori fixed order of weighted LP for the temporal variation, we choose suitable polynomial order by computing the relative error of the weighted LP expansions. Thus, the accuracy of the MOO scheme is guaranteed. A general principle for choosing the optimal scaling factor of LP is presented, which is crucial for efficiently predicting scattering information of objects. The fast Fourier transform (FFT)-based blocking scheme is also implemented to reduce the computational complexity to O(NS2 No log2 (No))Numerical results that demonstrate the accuracy and efficiency of this methodology are presented.

The dependence of chaos on two parameters of the cosmological constant and the self-interacting coef fi cient in the imaginary phase space for a closed Friedman-Robertson-Walker (FRW) universe with a conformally coupled scalar fi eld, as the full understanding of the dependence in real phase space, is investigated numerically. It is found that Poincare plots for the two parameters less than 1 are almost the same as those in the absence of the cosmological constant and self-interacting terms. For energies below the energy threshold of 0.5 for the imaginary problem in which there are no cosmological constant and self-interacting terms, an abrupt transition to chaos occurs when at least one of the two parameters is 1. However, the strength of the chaos does not increase for energies larger than the threshold. For other situations of the two parameters larger than 1, chaos is weaker, and even disappears as the two parameters increase.

Based on virtual reality technology, a friendly human-computer interaction interface and virtual machining environment were developed by Visual C++ and OpenGL. Considering the inhomogeneity of grain size and randomicity of grain distribution, virtual grinding wheel was modeled by taking ortho-hexahedron as basic shape of abrasive grains and randomly distributes them on the wheel base. Mathematic model of interference between abrasive grain and workpiece was established. By using the virtual grinding wheel modeled, surface grinding processes with different machining parameters were simulated. The simulation results show that the system could make operators have a further understanding to chip formation, and the machining results could reflect realistic surface topography of workpiece. Complex grinding process can be realistically simulated. It provides visualization models for the research of grinding mechanism and production forecast.

Astragalus mongholicus (AM) derived from the dry root of Astragalus membranaceus Bge. var. mongolicus (Bge.) Hsiao is a widely used traditional Chinese medicine. The present study investigated the potential role of AM on renal fibrosis on a rat model of unilateral ureteral obstruction (UUO). We divided 48 Sprague-Dawley rats randomly into 4 groups: sham-operated group (Sham), untreated UUO group, AM-treated (10 g/(kg x d)) UUO group, and losartan-treated (20 mg/(kg x d)) UUO group as positive control. Haematoxylineosin (HE) and Masson staining were used to study the dynamic histological changes of the kidneys 7 and 14 d after operation. The expressions of fibronectin (FN), type I collagen (colI), hepatocyte growth factor (HGF), transforming growth factor-beta1 (TGF-beta1), and alpha-smooth muscle actin (alpha-SMA) were analyzed by real-time polymerase chain reaction (PCR), immunohistochemistry staining, and Western blot. Results show that, similar to losartan, AM alleviated the renal damage and decreased the deposition of FN and colI from UUO by reducing the expressions of TGF-beta1 and alpha-SMA (P0.05), whereas HGF increased greatly with AM treatment (P0.05). Our findings reveal that AM could retard the progression of renal fibrosis. The renoprotective effect of AM might be related to inhibition of myofibroblast activation, inducing of HGF and reducing of TGF-beta1 expression.

In conventional statistical STAP algorithms, the existence of interference target in training samples will lead to signal cancellation, resulting in the output SCR falling and the moving target detection performance degrading. The nonhomogeneity detector is an efiective way to restrain the outlier, which can improve the covariance matrix estimation by detecting the samples containing outliers and rejecting them, and improve the STAP performance. A new interference target detection algorithm is proposed in this paper, the outlier detection is realized by using the samples' data phase information. Compared with traditional method, the improved algorithm is more sensitive to interfering target with difierent azimuth and intensity. Simulation results demonstrate the validity of this improved method.

For each object of an n-body problem in planetary dynamics, orbital elements except the mean anomaly are directly determined by five independently slow-varying quantities or quasi-integrals, which include the Keplerian energy, the three components of the angular momentum vector, and the z-component of the Laplace vector. The mean anomaly depends on the mean motion specified by the Keplerian energy. Decreasing integration errors of these quasi-integrals at every integration step means improving the accuracy of all the elements to a great extent. Because of this, we take reference values of these quantities in terms of the integral invariant relations as control sources of the errors and then give an extension of Nacozy's idea of manifold correction. The technique is almost the same as the linear transformation method of Fukushima in its explicit validity of correcting all elements, if the adopted basic integrators can give a necessary precision to the stabilizing sources considered. Especially it plays a more important role in significantly suppressing the growth of numerical errors in high eccentricities.

For each celestial body of multi-planet systems, there are two slowly varying quantities or quasi-integrals, Kepler energy and Laplace integral, which are closely associated with the orbital semimajor axis and eccentricity, respectively. To correct numerical errors of the quantities, we give an extension of Nacozy's approach and develop a new manifold correction method, where corresponding reference values of the quantities at every integration step are obtained from integral invariant relations, and only velocity corrections are used to approximately satisfy the two quasi-integrals. As a result, the scheme does enhance the quality of the integration by significantly raising the accuracy of the two elements. Especially, it is superior to the existing dual scaling method in the improvement of eccentricity in general when the adopted integrator provides a sufficient precision to the eccentricity.

Spindle-bearing system plays a crucial role in superhigh speed grinding, which directly affects machining precision, but it is complex and difficult to get the dynamic performance in experiment. This leads to study how to accurately simulate dynamic performance of spindle-bearing system. So a method which springs and damping units imitate bearing support is proposed in this paper. The proposed method can predict the regular pattern which bearing stiffness and damping ratio affect natural frequency and harmonic response. The research demonstrates that the method predicts well the dynamic performance of the spindle-bearing system and it is close to actual condition, therefore, it can be a reference for dynamic optimization design of spindle-bearing system in superhigh speed grinding.

Abrasive jet precision finishing is a new machining method, which injects slurry of abrasive and liquid solvent to grinding zone under without feed condition. The machining is simulated by Finite Element Method (FEM) in the paper. Hydrodynamic pressure on modeling of wedge-like grinding zone between wheel and workpiece on abrasive jet finishing with wheel as restraint was established and simulation, based on Navier-Stokes and continuity equations. The liquid hydrodynamic pressure distributing principle and affecting factor were investigated. The relation hydronamic pressure with grinding wheel velocity was stimulated and verified experimentally. The experiment results show that the simulation results are agreement with experiment, so the simulation model can well forecast hydrodynamic pressure distribution at contact zone.

As variants of the velocity–position single scaling method of Fukushima, which extends Nacozy’s manifold correction scheme to monitor the integrated position and velocity by using the integral invariant relation and the same spatial scale transformation, a new velocity scaling method and a new position scaling method for correcting the varying Kepler energy of each body in an n-body problem of planetary dynamics are presented. Compared with Fukushima’s idea, the new schemes are simple to operate. Like other existing methods including the method of Fukushima and of Wu et al., the two new methods not only are almost the same effectiveness in significantly improving the orbital semi-major axis or mean anomaly at the epoch, but also can raise the accuracy of numerical integration by several orders. In particular, the new velocity scaling method as well as the method of Wu et al. is the most convenient in application.

Raney Ni‐Al alloy in a dilute alkaline aqueous solution has been shown to be a powerful reducing agent, which is highly effective in the reduction of benzophenones to the corresponding hydrocarbon derivatives, in the absence of any organic solvents.