RP-HPLC method for the simultaneous determination of daidzein,genistein and formonetin in Solanum Lyratum Thunb

A rapid method for the simultaneous determination of daidzein, genistein and formonetin in solanum Lyratum Thunb by high performance liquid chromatography (HPLC) was developed. Separation was achieved on a Diamonsil C18 column (250 mm×4.6 mm, 5 μm) with isocratic elution, using a mobile phase of methanol-tetrahydrofuran-water (44∶3∶53, v/v). The wavelength was set at 260 nm and column was maintained at 35 ℃. The linear ranges of daidzein, genistein and formonetin were 1.0-40.0, 0.1-4.0 and 0.1-4.0 μg/mL, respectively. The average recoveries were between 98.4% and 101.3%. This method could be used for the quality control of Solanum lyratum Thunb due to its simplification, reliability, rapidity and excellent precision.     

Flow-injection-enhanced chemiluminescence method for the determination of three β-blockers

Objective To develop a rapid, simple and sensitive chemiluminescence method for the determination of three β-blockers (bisoprolol, atenolol and propranolol). Methods The chemiluminescence of cerium (Ⅳ)-sulfite system was obviously sensitized by adding anyone of three β-blockers in acid media. A new chemiluminescence method was set up by combining with flow-injection technique and used to determine the three β-blockers. Results Good linear ranges were obtained at the concentrations of 2.0×10-7g/mL-4.0×10-5g/mL, 1.0×10-7g/mL-3.0×10-5g/mL and 7.0×10-7g/mL-1.0×10-5g/mL, respectively, with the detection limits of 5.0×10-8g/mL, 7.0×10-8g/mL and 5.0×10-8g/mL (S/N=3), respectively, and the relative standard deviations for 11 times consecutive injections of 1.0×10-6g/mL bisoprolol, atenolol and propranolol were 3.57%, 2.21% and 2.26%, respectively. Conclusion The developed method is sensitive, accurate, rapid and of low cost. And it can be applied to determine bisoprolol, atenolol and propranolol in pharmaceutical preparations.     

Oleanolic acid-induced apoptosis and its relation with intracellular calcium in human lung adenocarcinoma A549 cells

Objective To investigate the effect of oleanolic acid (OA) on apoptosis, correlation between apoptosis and intracellular calcium, and its mechanism in human lung adenocarcinoma cell line A549. Methods Human lung adenocarcinoma A549 cells were incubated in vitro and assigned with OA concentrations of 0, 10, 20 and 40μg/mL. The apoptosis status of A549 cell line was detected with Annexin V-FITC/PI by flow cytometry (FCM); fluorescence intensity (FI) of A549 cells was assessed and the level of intracellular calcium was calculated at 24 hour of OA intervention. The relation between apoptosis and calcium FI was illustrated by curve fitting. Results FCM showed that 10, 20 and 40μg/mL of OA could induce A549 cell apoptosis, which followed a concentration-effect pattern; 24-hour intervention with 20μg/mL and 40μg/mL OA showed increased A549 cell apoptosis, and was significantly different from that with 0μg/mL OA (P<0.01). The FI of intracellular calcium concentration in 10, 20 and 40μg/mL OA groups was significantly higher than that in 0μg/mL group after 24 hours' intervention, and the FI showed a trend of increase with increased OA concentration (P<0.01). Curve fitting showed a significant correlation between apoptosis rate and intracellular calcium concentration in A549 cells (r=0.981, P<0.01). Regression equation was Y=0.508X-1.627. Conclusion OA plays a role in inducing apoptosis of human lung adenocarcinoma cells in a concentration-dependent manner. The OA-induced apoptosis is responsible for intracellular calcium overload of the tumor.     

Experimental study on the liquid slug of cryogenic slug flow in inclined tubes

An experimental study was carried out to understand the phenomena of the boiling flow of liquid nitrogen in inclined tubes with closed bottom by using a high speed motion analyzer.The experimental tubes are 0.018 and 0.014 m inner diameter(ID) and 1.0 m in length.The range of the inclination angle is 45°-90° from the horizontal.The experimental observation on the liquid slug was carried out along the tubes.Statistical method was employed to analyze the experimental data.The experiment analyzed the influences of the inclination angle and the tube diameter on the liquid slug length and velocity.The results show the liquid slug propagation velocity increases with the decrease of inclination angle θ.For all cases,the maximum values of the mean liquid slug lengths were obtained at θ = 60°.The mean liquid slug lengths were greater for large tube at higher tube position.These conclusions provide a basis for further study liquid slug of cryogenic two-phase undeveloped slug flow.     

Tool Wear Prediction in Micro-end-milling with Hard Material

The applications of micro-machining have increased drastically in the last ten years. However, tools with less than 1mm diameter using for micro-mills have very short and unpredictable life when they are used to cut hard metals. In this study, preliminary design of experiment (DOE) test program was conducted to investigate and identify the factors affecting tool wear at the micro-scale with hard material. Analysis of variance (ANOVA) and Taguchi method were efficient to determine appropriate cutting condition and the effect of parameters. A simple model was also developed to predict the width of slots on the workpiece along the cutting length. The obtained results can provide the basic guidelines for parameter setting of micro-end-milling with hard material.     

Rapid analysis of components in Rhizoma Anemarrhenae by HPLC-DAD-MS and HPLC-DAD-TOFMS

A global quality control method based on high performance liquid chromatography (HPLC) coupled with diode array detection (DAD), single quadrupole mass spectrometry (MS) and time-of-flight mass spectrometry (TOFMS) was developed for simultaneous determination of seven major components (mangiferin, neomangiferin, timosaponin E1, timosaponin E, timosaponin BⅡ, timosaponin BⅢ, and timosaponin AⅢ) and identification of most components in extracts of Rhizoma Anemarrhenae (RA). HPLC analysis was performed on an Agilent SB-C18 column (4.6 mm×150 mm, 5 μm) by gradient elution using acetonitrile and water-acetic acid(100∶0.05, v/v) as the mobile phase. Seven major components in RA were successfully separated. This quantitative method was fully validated in respect of the following performance criteria: linearity, precision, repeatability, stability, accuracy, limits of detection (LOD) and quantification (LOQ). A formula database of known compounds in RA was established, against which, most of the reported components in this herbal extract were identified effectively based on the extract masses acquired by TOFMS. This qualitative and quantitative method was successfully used to analyze the components in 10 batches of RA samples collected from different regions in China. This global quality control method, which consisted of HPLC-DAD-MS assay of seven major components and unambiguous identification of nineteen components, is suitable for routine quantification and comprehensive quality control of RA.     

STUDY ON NATURAL LANGUAGE INTERFACE OF NETWORK FAULT DIAGNOSIS EXPERT SYSTEM

Since Internet was born,the computer net workhas developed at a highspeedinits structure and ap-plication.Facing the huge and complex computernet work,we think it hard to deal with the variousfaults of the net work with manual method.Alongwiththe development of AI,the latest achievementof expert system(ES)has provided a new way forthe fault diagnosis and analysis of net work.Butthese ES don't provide a good interface for user.The interface of ES al ways uses command,menuand windows at pres…     

The development of an OxyHb animal model in mice and the study on OxyHb-induced apoptosis of mouse brain cells in vivo

Objective On the basis of developing a new animal model for oxyhemoglobin (OxyHb) injection into subarachnoid space in mice, this research was to explore the temporal dependence and spatial distribution of OxyHb- induced apoptosis in the mouse brain cells in vivo and the mechanism of neurocyte injury induced by OxyHb. Methods The animal model for OxyHb injection into subarachnoid space in mice was developed. Mice were divided randomly into the experimental group (n=40) and the control group (n= 35). The control group received saline injection (50 μL ) and the experimental group received OxyHb injection (50 μL ), both into the subarachnoid space. The mice of the two groups were subdivided according to different postoperative time (3 h, 6 h, 12 h, 24 h and 48 h). The apoptosis or necrosis of cells was distinguished with microscopy (HE staining), transmission electron microscopy and TUNEL method. Results The distribution of apoptosis was mainly in the ipsilateral neocortex and bilateral hippocampal gyrus. The apoptotic mouse brain cells showed morphological changes in the experimental group by HE staining and transmission electron microscopy. The count of TUNEL-positive cells showed substantial increase in the experimental group, and there was a significant difference between the control and experimental groups, and the number of OxyHb- induced apoptotic cells decreased with time. Conclusion OxyHb in subarachnoid space in mice can induce apoptasis, but not necrosis of mouse brain cells in viro. The apoptotic brain cells show the pattern of temporal dependence and spatial distribution. It is suggested that the early treatment should be the method of first choice for treating the hemorrhagic brain injury.     

Predicting the Dielectric Strength of c-C4F8 and SF6 Gas Mixtures by Monte Carlo Method

An improved Monte Carlo method was used to simulate the motion of electrons in c-C_4F_8 and SF_6 gas mixtures for pulsed townsend discharge. The electron swarm parameters such as effective ionization coefficient, [AKα-] and drift velocity over the E/N range from 280～700 Td(1Td=10-21 V·m2) were calculated by employing a set of cross sections available in literature. From the variation cure of [AKα-] with SF_6 partial pressure p, the limiting field (E/N)_lim of gas mixture at different gas content was determined. It is found that the limiting field of c-C_4F_8 and SF_6 gas mixture is higher than that of pure SF_6 at any SF_6 mixture ratio. Simulation results show excellent agreement with experiment data available in previous literature.     

The Dimensions of Graphs and Constructions of Their Bases

IntroductionGraph G,considered in this paper,is finiteand simple with vertex set V ( G) and edge setE( G) .Let d( x,y) denote the distance between xand y in G and W={w1,w2 ,…,wk}denote the or-dered set of V( G) .For any given v∈V( G) ,therepresentation of v with respect to W is the k- vec-tor:r( v| W) ={d( v,w1) ,d( v,w2 ) ,…,d( v,wk) }.The ordered set W is called a resolving set of G ifr( u| W) =r( v| W) implies that u=v for all pairs{u,v}of vertices of G. A resolving set of G with…     

Efficient Design and Optimization Method for Distributed Amplifiers

A novel design and optimization method for distributed amplifiers(DAs)is proposed to make the circuit design more convenient and efficient.This method combines artificial intelligence(AI)optimization with manual design by two loops,i.e.,outer manual loop and inner AI loop.The layout design is followed by AI optimization to take more influencing factors such as parasitic effect into account for the practicability.A DA with three gain cells is designed and optimized in a standard 0.18μm complementary metal-oxide-semiconductor(CMOS)technology to verify the proposed method.With a chip area of only 0.55 mm2,the DA provides 9.8 dB average forward gain from 1 to 15.2 GHz.The output power at 1 dB output compression point is more than 7.7 dBm in the 2-14 GHz frequency band and the peak power-added efficiency(PAE)is 10.6%.The measurement results validate the proposed method as a robust DA design procedure for improving circuit performance and design efficiency.     

DETERMINATION OF POLYDATIN IN POLYGONUM CUSPIDTUM SIEB. ETZUCC. BY TLC-FLUORESCENCE SPECTROPHOTOMETRY

Objective A method of TLC-fluorescence spectrophotometry was established to assay the content of polydatin in polygonum cuspidatum sieb. et zucc. Methods: Polydatin was extracted by methanol and separated with ch‘loroform-acetone-formic acid-water (4:4:0.5:0.2) by thin layer chromatography. The excitation wavelength and emission wavelength were 284 nm and 384 nm, respectively. Results The linear regression equation of the calibrationgraph was y=7.02179x 4.5143, a linear regression correlative coefficient r= 0. 9936. Conclusion This method was proved simple, stable and sensitive. It can be used in quality control of herbs.     

Nonlinear Statistical Process Monitoring Based on Control Charts with Memory Effect and Kernel Independent Component Analysis

A novel nonlinear combination process monitoring method was proposed based on techniques with memory effect (multivariate exponentially weighted moving average (MEWMA)) and kernel independent component analysis (KICA). The method was developed for dealing with nonlinear issues and detecting small or moderate drifts in one or more process variables with autocorrelation. MEWMA charts use additional information from the past history of the process for keeping the memory effect of the process behavior trend. KICA is a recently developed statistical technique for revealing hidden, nonlinear statistically independent factors that underlie sets of measurements and it is a two-phase algorithm: whitened kernel principal component analysis (KPCA) plus independent component analysis (ICA). The application to the fluid catalytic cracking unit (FCCU) simulated process indicates that the proposed combined method based on MEWMA and KICA can effectively capture the nonlinear relationship and detect small drifts in process variables. Its performance significantly outperforms monitoring method based on ICA, MEWMA-ICA and KICA, especially for long-term performance deterioration.     

The study of correlative factors to resistin and its regression equation in type 2 diabetes

Objective To study the changes of resistin and the relationship between resistin and other indexes in patients with type 2 diabetes mellitus. Methods Seventy patients with type 2 diabetics were chosen and divided into three groups according to weight index and 15 healthy persons were chosen as controls. ELISA was adopted to determine resistin concentration. Oxydase method was adopted to measure blood sugar. Radio immunoassay was used to measure insulin level. Results Resistin concentration of patient groups r(23.06±9.34)μg/L ] was significantly higher than that of control group [( 9. 89±4. 47) μg/L, P<0. 01 ]. Resistin was positively related to body mass index (r = 0.4 467) and fat distribution (r= 0. 3 314, P<0.01). Resistin was also positively correlated to the area under the curve of sugar tolerance (r=0. 7 063, P<0. 01), negatively related to the insulin resistance index (r=-0. 4 154, P<0.01), but not related to area under the curve of synchronous insulin release (P>0. 05). And a formula was obtainted : Resistin=- 15. 869 0. 339×GAUC 0.790×BMI. Conclusion The level of reslstin in type 2 diabetics is higher. And reslstin is related to other factors. This formula is of great significance for clinical study of diabetic's disor- ders.     

Model for evaluating the ecological health of municipal solid waste treatment system

Ecological municipal solid waste （MSW） treatment systems are complex systems engineering concerning with multiple objectives and hierarchical levels. By combining an extension method with fuzzy logic theory, this paper investigated key technologies required by the comprehensive evaluation of ecological health. The method includes the construction of an evaluation system, quantification of evaluation indices, development of a matter-element model, development of an extension evaluation method, and assignment of a blended weight that combines subjectively and objectively estimated weights. This approach was used to develop a compre- hensive model for evaluating the ecological health of an ecological treatment system for MSW. The model was then applied to a case study, and the results demonstrated that the model is a reasonable and effective.     

New Maintenance Strategies for Generating Companies in Power Market

A new approach to maintenance scheduling of generating units(MSU)in competitive electricity markets was presented,which was formulated as a noncooperative game with complete information.The payoff of each generating company(Genco)was defined as the profit from the energy auction market minus maintenance cost and risk loss.The compensation fee of interruptible load was a part of the maintenance cost when the permitted maintenance capacity in the system was insufficient.Hourly energy auction was incorporated in the computation of both revenues from energy market and risk loss of maintenance strategy as a nested game.A new heuristic search algorithm for the calculation of the game equilibrium of MSU was presented,which coordinates the solutions of non-equilibrium,unique equilibrium and multiple equilibria.Numerical results for a two-Genco system and a realistic system were used to demonstrate the basic ideas and the applicability of the proposed method,as well as its computational efficiency.     

Adaptive Identification of Logging Lithology Based on VPSO-ENN Hybrid Algorithm

Particle swarm optimization (PSO) was modified by variation method of particle velocity, and a variation PSO (VPSO) algorithm was proposed to overcome the shortcomings of PSO, such as premature convergence and local optimization. The VPSO algorithm is combined with Elman neural network (ENN) to form a VPSO-ENN hybrid algorithm. Compared with the hybrid algorithm of genetic algorithm (GA) and BP neural network (GA-BP), VPSO-ENN has less adjustable parameters, faster convergence speed and higher identification precision in the numerical experiment. A system for identifying logging parameters was established based on VPSO-ENN. The results of an engineering case indicate that the intelligent identification system is effective in the lithology identification.     

Finite Element Modeling of a Fluid Filled Cylindrical Shell with Active Constrained Layer Damping

On the basis of the piezoelectric theory, Mindlin plate theory, viscoelastic theory and ideal fluid equation, the finite element modeling of a fluid-filled cylindrical shell with active constrained layer damping （ACLD） was discussed. Energy methods and Lagrange＇s equation were used to obtain dynamic equations of the cylindrical shell with ACLD treatments, which was modeled as well with the finite element method. The GHM （Golla-Hughes-McTavish） method was applied to model the frequency dependent damping of viscoelastic material. Ideal and incompressible fluid was considered to establish the dynamic equations of the fluid-filled cylindrical shell with ACLD treatments, Numerical results obtained from the finite element analysis were compared with those from an experiment. The comparison shows that the proposed modeling method is accurate and reliable.     

Key Technology of 3D Geosciences Modeling in Coal Mine Engineering

A new method for simulation technology of laneway engineering seamless excavation based on 3D geoscience modeling(3DGM)was proposed to overcome the deficiency in current research.The generalized triprism(GTP)data model was used as the basic modeling element in this method.The models of geological body were created by the method of rock pillar body partition(RPBP)modeling.The laneway engineering models were built with component method,while the corresponding triangles in sections were connected and transformed into tunnel GTP models.All the GTP models were converted into tetrahedron models based on the smallest vertex identifier(SVID).The simulation and spatial analysis of laneway engineering seamless excavation could be realized through the local hierarchical intersection(LHI)algorithm.The application case showed that the method was fast and effective,and it could meet the needs of design and spatial analysis for mine laneway engineering.