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This paper presents a combined experimental and computational study of unsteady flows in a linear turbine cascade oscillating in a three-dimensional bending/flapping mode. Detailed experimental data are obtained on a seven-bladed turbine cascade rig. The middle blade is driven to oscillate and oscillating cascade data are obtained using an influence coefficient method. The numerical simulations are performed by using a 3D nonlinear time-marching Navier-Stokes flow solver. Single-passage domain computations for arbitrary interblade phase angles are achieved by using the Fourier shape correction method. Both measurements and predictions demonstrate a fully 3D behavior of the unsteady flows. The influence of the aerodynamic blockage introduced by part-span shrouds on turbine flutter has been investigated by introducing flat plate shaped shrouds at 75% span. In contrast to practical applications, in the present test configuration, the mode of vibration of the blades remains unchanged by the introduction of the part-span shroud. This allows the influence of the aerodynamic blockage introduced by the part-span shroud to be assessed in isolation from the change in mode shape. A simple shroud model has been developed in the computational solver. The computed unsteady pressures around the shrouds are in good agreement with the experimental data, demonstrating the validity of the simple shroud model. Despite of notable variations in local unsteady pressures around the shrouds, the present results show that the blade aerodynamic damping is largely unaffected by the aerodynamic blockage introduced by part-span shrouds. [DOI: 10.1115/1.3111254]

Abstract: Hordeum vulgare subsp. spontaneum, the wild progenitor of barley, is a potential source of useful genetic variation for barley breeding programs. The objective of this study was to map [...]

Lactic Acid Bacteria (LAB) regulate and maintain the stability of healthy microbial flora, inhibit the adhesion of pathogenic bacteria and promote the colonization of beneficial micro‐organisms. The drug resistance and pathogenicity of Salmonella enteritis SE47 isolated from retail eggs were investigated. Meanwhile, Enterococcus faecalis L76 and Lactobacillus salivarius LAB35 were isolated from intestine of chicken. With SE47 as indicator bacteria, the diameters of L76 and LAB35 inhibition zones were 12 mm and 8·5 mm, respectively, by agar inhibition circle method, which indicated that both of them had inhibitory effect on Salmonella, and L76 had better antibacterial effect; two chicken‐derived lactic acid bacteria isolates and Salmonella SE47 were incubated with Caco‐2. The adhesion index of L76 was 17·5%, which was much higher than that of LAB35 (10·21%) and SE47 (4·89%), this experiment shows that the higher the bacteriostatic effect of potential probiotics, the stronger the adhesion ability; then Caco‐2 cells were incubated with different bacteria, and the survival of Caco‐2 cells was observed by flow cytometry. Compared with Salmonella SE47, the results showed that lactic acid bacteria isolates could effectively protect Caco‐2 cells; finally, after different bacteria incubated Caco‐2 cells, according to the cytokine detection kit, the RNA of Caco‐2 cells was extracted and transcribed into cDNA, then detected by fluorescence quantitative PCR, the results showed that L76 could protect Caco‐2 cells from the invasion of Salmonella SE47, with less cell membrane rupture and lower expression of MIF and TNF genes. Therefore, the lactic acid bacteria isolates can effectively inhibit the adhesion of Salmonella and protect the integrity of intestinal barrier. [ABSTRACT FROM AUTHOR]

Fast online acquisition of particle size distribution has become a significant technique for both laboratory research and industrial application. In this paper, a particle sizing method based on the analysis of scatted light through image processing is proposed. Polarization ratio, which is defined by the ratio of the scattered intensity component polarized perpendicular to that polarized parallel, is induced to quantify the polarization status which, according to Mie scattering theory, is dependent on the particle diameter under a certain operating condition when the refractive index of the particle is known. Test rig is set up to realize the simultaneous acquisition of particle images polarized both perpendicular and parallel on CCD camera. Through image processing, the polarization ratio of the scattered light is obtained, based on which inverse calculation is performed according to Mie theory. The presented method is then applied to the size distribution determination of polystyrene particles suspending in water. The results obtained from experiments are compared with the calibrated values which renders a deviation less than 10%. The optical setup is also applied to the sizing of water droplets generated by an atomizer, which provides reasonable size distributions under different operating conditions in line with the reference values provided by the fabricator. [ABSTRACT FROM AUTHOR]

Abstract: A swirling flow has been induced in a premixed gas-fired impinging circular flame jet by adding two tangential air flows to the main axial air/fuel flow. The flame jet system was considered to be small-scale and operated under low-pressure, laminar flow conditions. The effects of Reynolds number of the air/butane mixture and nozzle-to-plate distance on the heating performance of the flame were studied and compared with the heat-flux distributions on an impingement plate under different operating conditions. The whole investigation was conducted under the stoichiometric air/fuel condition (i.e., equivalence ratio, Φ =1) with the Reynolds number being varied from 800 to 1700, and nozzle-to-plate distance being selected between 1.5 and 4.0. The introduction of swirl to small-scale, low-pressure, laminar premixed gas-fired impinging circular flame jets is the method for enhancing their thermal performances. The heat-flux distribution on the impingement plate was more uniform and the flame temperatures essentially higher when compared with a similar flame jet system without induced swirl. [Copyright &y& Elsevier]

We obtain analytically a universal expression of the resonant energies for any one-dimensional (1D) models with the defects having symmetric internal structures. In a 1D periodic system with the on-site energy ε0 = 0 and a nearest-neighbor matrix element t0 = 1.0, two classes of the most interesting and simplest wavefunction behaviors are numerically obtained for the resonant energies around (a) 0, ±1, (b) ±(√5-1)/2, √2, ±√3, respectively. We show that similar wavefunction behaviors can be found widely in many quasiperiodic and random systems where the delocalization phenomena are predicted. We suggest that the envelope of these wavefunctions can be generally used as a criterion of delocalization of electronic states in 1D random and quasiperiodic lattices. [ABSTRACT FROM AUTHOR]

Powdery mildew, caused by Erysiphe graminis DM f. sp. tritici (Em. Marchal), is one of the most important diseases of common wheat world-wide. Chinese wheat variety 'Fuzhuang 30' carries the powdery mildew resistance gene Pm5e and has proven to be a valuable resistance source of powdery mildew for wheat breeding. Microsatellite markers were employed to identify the gene Pm5e in a F2 progeny from the cross 'Nongda 15' (susceptible) × 'Fuzhuang 30' (resistant). The gene Pm5e was mapped in the distal region of chromosome 7BL. Seven microsatellite markers were found to be linked to the gene Pm5e, of which two codominant markers Xgwm783 and Xgwm1267 were relatively close to Pm5e with a linkage distance of 11.0 cM and 6.6 cM, respectively. It is possible to use the 136-bp allele of Xgwm1267 in 'Fuzhuang 30' for marker-assisted selection during the wheat resistance breeding process for facilitation of gene pyramiding. The mapping information in the present study provides a starting point for fine mapping of the Pm5 locus and map-based cloning to clarify the molecular structure and function of the different alleles at the Pm5 locus. A microsatellite linkage map of chromosome 7B was constructed with 20 microsatellite loci, nine on the short arm and 11 on the long arm. This information will be very useful for further mapping of agronomically important genes of interest on chromosome 7B. [ABSTRACT FROM AUTHOR]

Multiple perfect transmissions of electromagnetic waves are found in the photonic band gap of the symmetric dielectric heterostructures (SDH) constructed as (AB)nBm(BA)n, where A and B stand for different dielectric materials, and m and n are the repeating numbers of the units. The photonic frequency and the mode number of resonant transmissions therein can be manipulated by varying m, and the quality factor Q of the perfect transmission peak increases exponentially with increasing n. These features are experimentally demonstrated in a SDH of TiO2/SiO2 for visible and near infrared light. The possible applications of SDH for the wavelength division multiplexing system are discussed. [ABSTRACT FROM AUTHOR]

A temperature‐ and strain‐independent torsion sensor based on analysis of polarisation‐dependent loss (PDL) characteristics of high‐birefringent (Hi‐Bi) fibre Bragg gratings (FBGs), is proposed and demonstrated. Unlike the amplitude spectra, the PDL response has higher sensitivity to torsion. Experimetal results demonstrate that the difference between the two peaks in the PDL spectra has a linear relationship with the twist rate, but remains invariant with changes in temperature and strain. In addition, it was observed that the PDL responses to the clockwise twist are just opposite of the responses to the couterclockwise twist. [ABSTRACT FROM AUTHOR]

Highlights: [•] Three-dimensional Voronoi structure was generated to model metallic foams. [•] Contact between cell walls was considered under compression deformation. [•] Damage and failure of cell walls were considered under tensile deformation. [•] The deformation characteristics are due to the formation of plastic bands. [•] Pore irregularity was introduced to quantify the heterogeneous structure. [ABSTRACT FROM AUTHOR]

Abstract: G protein–coupled receptor 17 (GPR17), the new P2Y-like receptor, is phylogenetically related to the P2Y and cysteinyl leukotriene receptors, and responds to both uracil nucleotides and cysteinyl leukotrienes. GPR17 has been proposed to be a damage sensor in ischemic stroke; however, its role in brain inflammation needs further detailed investigation. Here, we extended previous studies on the spatiotemporal profiles of GPR17 expression and localization, and their implications for brain injury after focal cerebral ischemia. We found that in the ischemic core, GPR17 mRNA and protein levels were upregulated at both 12–24 h and 7–14 days, but in the boundary zone the levels increased 7–14 days after reperfusion. The spatiotemporal pattern of GPR17 expression well matched the acute and late (subacute/chronic) responses in the ischemic brain. According to previous findings, in the acute phase, after ischemia (24 h), upregulated GPR17 was localized in injured neurons in the ischemic core and in a few microglia in the ischemic core and boundary zone. In the late phase (14 days), it was localized in microglia, especially in activated (ED1-positive) microglia in the ischemic core, but weakly in most microglia in the boundary zone. No GPR17 was detectable in astrocytes. GPR17 knockdown by a small interfering RNA attenuated the neurological dysfunction, infarction, and neuron loss at 24 h, and brain atrophy, neuron loss, and microglial activation at 14 days after reperfusion. Thus, GPR17 might mediate acute neuronal injury and late microgliosis after focal cerebral ischemia. [Copyright &y& Elsevier]

Abstract: Cysteinyl leukotrienes (CysLTs), potent inflammatory mediators, are released from ischemic brain, and may regulate ischemic injury through activating CysLT1 and CysLT2 receptors. The CysLT1 receptor is closely associated with ischemic injury and post-ischemic repair; however, the CysLT2 receptor-mediated responses remain unknown. Here, we investigated the spatiotemporal profiles and implications of CysLT2 receptor expression and localization in rat brain after focal cerebral ischemia. CysLT2 receptors were normally localized in astrocytes in the cortex and around the ventricles. After focal cerebral ischemia, CysLT2 receptor expression was up-regulated in concert with neuronal and glial responses. In the acute phase (6–24 h), up-regulated CysLT2 receptors were restricted to injured neurons in the ischemic core; while in the late phase (3–28 days), the up-regulation was restricted to hypertrophic microglia (ischemic core) and mainly localized in hypertrophic astrocytes (boundary zone). Thus, the spatiotemporal profiles of CysLT2 receptor expression suggest that it plays regulatory roles in acute neuron injury, and astrocytosis and microgliosis in the late phase. [Copyright &y& Elsevier]

Abstract: We report on the photoluminescence (PL) properties of InAs/InAlAs/InP quantum wires (QWRs) with various InAs deposited thickness. The PL linewidth of the QWRs decreases with increasing InAs deposited thickness due to the different thicknesses of the QWRs and defects in the samples. The defects and lateral composition modulation of the InAlAs layers play an important role in the temperature-dependent PL properties of the samples. [Copyright &y& Elsevier]

Abstract: In this paper, polycrystalline Sr2Fe1− x Al x MoO6 (x=0.0, 0.05, 0.10, 0.15, 0.30) samples were fabricated by traditional solid-state reaction. X-ray diffraction and scan electron microscopy show that all samples have single double perovskite structure and no obvious change was found in the grain size and grain boundary after doping. The magnetoresistance of Sr2FeMoO6 was greatly enhanced by doping Al as x increased from zero to 0.30, but it showed a maximum at x=0.15 under high field over 0.5T. These phenomena were found to originate from the change of intragranular spin-dependent scattering in Sr2FeMoO6 after doping Al. The role of the replacement of Fe with Al is twofold. Firstly, it broke the ferrimagnetic chain of O–Fe–O–Mo–O into smaller chains that become more sensitive to the external magnetic field. So the low-field magnetoresistance was enhanced remarkably with the increase of Al. Secondly, it suppressed the antiferromagnetic exchange in the antiphase boundary arising from the anti-site defects. So the spin in the antiphase boundary appeared to align more easily to the external magnetic field and the high-field magnetoresistance was decreased gradually with increasing the doping concentration. Therefore, the magnetoresistance of Sr2FeMoO6 reaches a threshold saturated value at x=0.15 at high field. However, doping Al also make the magnetoresistance of SFMO show stronger temperature dependence. [Copyright &y& Elsevier]

Abstract: We present the structural fabrication and the optical transmission of dielectric multilayer films with a defect both theoretically and experimentally. With the transfer-matrix method, the transmission of electromagnetic waves through the multilayer can be theoretically analyzed. It is shown that a defect layer in the structure can induce the localized mode that is shown as the transmission peak in the photonic band gap (PBG). Both the intensity and the quality factor of the peak definitely change with adjusting the position of the defect in the multilayer. Further, the number of transmission peaks in the PBG can be tuned by changing the thickness of the defect layer. In the experiment, a series of multilayer films with the defect layer have been fabricated using the electron-gun evaporation technique. Optical measurements are in good agreement with theoretical predictions. The investigation achieves the possible application to the wavelength division multiplexing system. [Copyright &y& Elsevier]