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With the rapid increasing number of Web services in service network, how to discover the desired trustworthy service quickly and accurately has been a hot issue of service-oriented computing. In open network environment, the efficiency of trusted service discovery is low. Take advantage of the properties of "small-world", the paper proposed a trusted service discovery method which based on trust and recommendation relationships. Firstly, an open service network model with trust and recommendation relationships was proposed. The two relationships in the model were defined. Then, based on the model and the trust and recommendation relationships, a dynamic trusted service discovery algorithm was presented. The trusted service discovery method can reduce the searching path and search trusted services for service requester in a short time. Finally, the-results of the simulation experiences showed that this method can return satisfactory trusted services quickly and efficiency. [ABSTRACT FROM AUTHOR]

Abstract: A HPLC method using a NH2 column for determination of melamine was reported, with acetonitrile-H3PO4 (15 mmol L−1, pH = 6.5) (V/V = 88:12) as mobile phase and UV detection at 215 nm. The tested parameters included mobile phase composition, percentage of organic solvent, and buffer concentration, and pH value and UV detection wavelength. Good linearity was observed within the concentration range of 0.005–32 mg L−1 (n = 7, r = 0.9997), the detection limit was 0.003 mg L−1 (S/N = 3). The chromatography mode was considered to be hydrophilic interaction chromatography (HILIC). The method was successfully applied to determine melamine in several dairy products, with acetonitrile as extract solvent of melamine and also as protein precipitant. The spike recovery of melamine was within 73–96%. [Copyright &y& Elsevier]

Internet has become an important platform for people to get information, but not all the information from internet is true (or correct). For one thing, many data sources get data from fallible providers or copy from other data sources. For another thing, data sources inevitably make some mistakes in the process of providing data and consequently different data sources frequently provide conflict data. Untrue data can cause a loss to users, so it is important to identify truth data. This work proposed an algorithm to compute trust network of data sources based on the degree of agreement among data sources. Based on the trust network of data sources, this work proposed a trust-based method, called "TruData", by way of computing the trust values of data sources and data items, to discovery truth data. The experiments show that TruData has a good result in identifying truth data for big data set. [ABSTRACT FROM AUTHOR]

Purpose: Respiratory motion introduces uncertainties in tumor location and lung deformation, which often results in difficulties calculating dose distributions in thoracic radiation therapy. Deformable image registration (DIR) has ability to describe respiratory-induced lung deformation, with which the radiotherapy techniques can deliver high dose to tumors while reducing radiation in surrounding normal tissue. The authors' goal is to propose a DIR method to overcome two main challenges of the previous biomechanical model for lung deformation, i.e., the requirement of precise boundary conditions and the lack of elasticity distribution. Methods: As opposed to typical methods in biomechanical modeling, the authors' method assumes that lung tissue is inhomogeneous. The authors thus propose a DIR method combining a varying intensity flow (VF) block-matching algorithm with the finite element method (FEM) for lung deformation from end-expiratory phase to end-inspiratory phase. Specifically, the lung deformation is formulated as a stress-strain problem, for which the boundary conditions are obtained from the VF block-matching algorithm and the element specific Young's modulus distribution is estimated by solving an optimization problem with a quasi-Newton method. The authors measure the spatial accuracy of their nonuniform model as well as a standard uniform model by applying both methods to four-dimensional computed tomography images of six patients. The spatial errors produced by the registrations are computed using large numbers (>1000) of expert-determined landmark point pairs. Results: In right-left, anterior-posterior, and superior-inferior directions, the mean errors (standard deviation) produced by the standard uniform FEM model are 1.42(1.42), 1.06(1.05), and 1.98(2.10) mm whereas the authors' proposed nonuniform model reduces these errors to 0.59(0.61), 0.52(0.51), and 0.78(0.89) mm. The overall 3D mean errors are 3.05(2.36) and 1.30(0.97) mm for the uniform and nonuniform models, respectively. Conclusions: The results indicate that the proposed nonuniform model can simulate patient-specific and position-specific lung deformation via spatially varying Young's modulus estimates, which improves registration accuracy compared to the uniform model and is therefore a more suitable description of lung deformation. [ABSTRACT FROM AUTHOR]

Kiwifruit ( Actinidia eriantha Benth.) ‘White’, a novel cultivar with higher L-ascorbic acid (AsA) level, is registered in China. Changes in AsA, related metabolites, enzymatic activity, and gene expression associated with AsA biosynthesis and recycling process were investigated in this paper. The results indicated that AsA biosynthesis through L-galactose pathway supplemented by D-galacturonic acid pathway and AsA recycling collectively contributed to accumulating and remaining higher AsA level in kiwifruit cv. ‘White’ during postharvest. Moreover, L-galactose dehydrogenase (GalDH) activity and relative expressions of the genes encoding GDP-D-mannose pyrophosphorylase (GMP), L-galactose-1-P phosphatase (GPP), GDP-L-galactose phosphorylase (GGP), GalDH and D-galacturonate reductase (GalUR) were important for regulation of AsA biosynthesis, and the activity and expression of dehydroascorbate reductase (DHAR) were primarily responsible for regulation of AsA recycling in kiwifruit ‘White’ during postharvest. [ABSTRACT FROM AUTHOR]

Gaussian-based HF/MP2 and DFT/B3LYP methods have been explored to study the microsolvation of glycine anion with water, [Gly]-(W) n, and 1-ethyl-3-methylimidazolium glycine ionic liquid (IL) with water, [EMIM][Gly](W) n, n = 1-6 and 12. The water molecules are either isolated or aggregated around [Gly]- and [EMIM][Gly]. Their electronic structures have been calculated clearly to verify the molecular state of H2O and the results were used to compare with experiments. The water effect on the interaction energies and local packing of [EMIM][Gly] is considered. We identified an important factor: the variation of [EMIM][Gly](W) n polarity with the different numbers of H2O. As the amount of H2O increases, the polar network is continuously broken up. The dipole moments are changed to be lowest when the H-bonding ability of [Gly]- is almost saturated. Meanwhile, the nonpolar groups of the cation form an enhanced aggregation. Such observation can provide initial insights for the experimental nanostructural evolution in the IL-water mixtures. [ABSTRACT FROM AUTHOR]

Abstract: A microfluidic pool structure for cell docking and rapid mixing is described. The pool structure is defined as a microchamber on one structural layer of a bilayer chip and connects with two or more individual microchannels on the other structural layer. In contrast to the turbulent flow in a macroscale pool, laminar streams enter and exit this microfluidic pool structure with definite and controllable direction that may be influenced by the location and geometry of the pool. A simple microfluidic model was used to validate this hypothesis. In this model, a microscale pool structure was made on the lower layer of a chip and connected with three parallel microchannels in the upper layer. Simulation and experimental results indicated that the flow profile within the pool structure was determined by its geometry and location. This could be used as a flow control method and it was simpler than designs based on microvalve, hydraulic pressure, or electrokinetic force, and has some important applications. For example, controllable streams within this structure were used to immobilize biological cells along the microchannel walls. When different solution streams flowed through the pool, rapid diffusion of analytes occurred for short diffusion distance between vertical flow laminas. Furthermore, desired dilution (mixing) ratio could be obtained by controlling the geometry of the microfluidic pool. [Copyright &y& Elsevier]

We perform a first-principles study of the mechanical and vibrational properties of ZnS with a wurtzite structure. The calculated elastic constants by using a pseudopotential plane-wave method agree well with the experimental data and with the previous theoretical works. Based on the elastic constants and their related parameters, the crystal mechanical stability is discussed. Calculations of the zone-center optical-mode frequencies including longitudinal-optical/transverse-optical splitting, by using the density functional perturbation theory, are reported. All optical modes are identified, especially B1 modes, and agree with Raman measurements. [ABSTRACT FROM AUTHOR]