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101.
A novel integrated polarisation beam splitter on a silica-based planar lightwave circuit that utilises the waveguide birefringence dependence on waveguide core width is proposed. It was successfully confirmed that the fabricated splitter has a polarisation extinction ratio of >21 dB over a wide wavelength range of 1530 to 1620 nm  相似文献   
102.
A nitrogen (N)-doped diamond-based electron emitter has been fabricated by the sintering technique prior to the chemical vapor deposition process in order to improve the uniformity. There are no spatial differences in reflective electron energy loss spectra (REELS) from the diamond-based electron emitter, suggesting that uniform surface conditions are obtained. The uniform electron emission from the obtained electron emitter is confirmed through emission current vs anode voltage characteristics measurements. It seems that the uniformity of the emitter surface results in uniform electron emission from the diamond electron emitter  相似文献   
103.
This article describes a novel laser-directed microfabrication method carried out in aqueous solution for the organization of cell networks on a platform. A femtosecond (fs) laser was applied to a platform culturing PC12, HeLa, or normal human astrocyte (NHA) cells to manipulate them and to facilitate mutual connections. By applying an fs-laser-induced impulsive force, cells were detached from their original location on the plate, and translocated onto microfabricated cell-adhesive domains that were surrounded with a cell-repellent perfluoroalkyl (R(f)) polymer. Then the fs-laser pulse-train was applied to the R(f) polymer surface to modify the cell-repellent surface, and to make cell-adhesive channels of several μm in width between each cell-adhesive domain. PC12 cells elongated along the channels and made contact with others cells. HeLa and NHA cells also migrated along the channels and connected to the other cells. Surface analysis by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) confirmed that the R(f) polymer was partially decomposed. The method presented here could contribute not only to the study of developing networks of neuronal, glial, and capillary cells, but also to the quantitative analysis of nerve function.  相似文献   
104.
The development of information technology has made it possible to obtain large amounts of information easily. Thus it appears likely that the impact on a society of word‐of‐mouth information communication and the like has been growing. In this paper, we propose a model of the emergence of opinion leaders based on word of mouth in an artificial stock market. The process of emergence of opinion leaders and the impact of opinion leaders on stock prices are verified by simulation. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 177(2): 32–40, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21163  相似文献   
105.
In this paper, the dual underexpanded impinging jets are experimentally and numerically studied. The experiments were performed by measuring the unsteady and averaged wall static pressures and by visualizing density fields using schlieren method. Numerical calculations were also conducted by solving unsteady three dimensional compressible Navier-Stokes equations with Baldwin-Lomax turbulence model. The main parameters for the dual jets are the non-dimensional distance between the two nozzle centers HID covering 1.5, 2.0, the nozzle to plate separation LID 2.0, 3.0,4.0 and 5.0 and the pressure ratio defined by po/pb 1.0~6.0, where D is the diameter of each nozzle exit, p0 the stagnation pressure and pb the back pressure. It is found that the agreement between the experiments and the calculations is good. The fountain flow at the middle of the two jets is observed both in the experiments and the calculation. According to FFT analysis of the experiments for the twin jets, relatively low frequency (up to 5  相似文献   
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108.
Idiopathic eosinophilic pneumonia (IEP) is characterized by the accumulation of eosinophils in the alveolar spaces and the interstitium of the lung, frequently accompanied by peripheral eosinophilia. To clarify the roles of adhesion molecules of eosinophils in the pathogenesis of eosinophilic pneumonia, we analysed their expression by eosinophil and T-lymphocyte populations in peripheral blood and bronchoalveolar lavage fluid (BALF) obtained from 11 patients with eosinophilic pneumonia, using flow cytometric methods. Cell differentials in BALF showed increased numbers of eosinophils, the increase correlating with the number of activated T-lymphocytes in BALF. The expressions of CD11a (lymphocyte function-associated antigen-1 (LFA-1)), CD11b (Mac-1), CD18, CD49d (very late activation antigen-4 (VLA-4)), and CD62L (L-selectin) by eosinophils in BALF were all lower than those of eosinophils in peripheral blood. In contrast, CD54 (intercellular adhesion molecule-1 (ICAM-1)) was expressed by eosinophils in BALF, but not by those in peripheral blood. These results indicate that intercellular adhesion molecule-1 expression by eosinophils in bronchoalveolar lavage fluid but not in peripheral blood may be induced by locally activated T-cells or macrophages and may be important in the pathogenesis of idiopathic eosinophilic pneumonia.  相似文献   
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110.
Newly synthesized heparin-containing block copolymers, consisting of a hydrophobic block of polystyrene (PS), a hydrophilic spacer-block of poly (ethylene oxide) (PEO) and covalently bonded heparin (Hep) as bioactive block, were coated either onto glass, poly (dimethylsiloxane), polyurethane or PS substrates. Coated surfaces were characterized by determination of the surface-bound heparin activity, adsorption of AT III, plasma recalcification time assays, adhesion of platelets and by an ex vivo rabbit A-A shunt model.It was demonstrated that heparin was available at the surface of all heparin-bound surfaces to interact with AT III and thrombin and to prevent the formation of clots. The maximum immobilized heparin activity was found to be 5.5×10-3 U cm-2. Coated surfaces showed a significant prolongation of the plasma reclacification times as compared to control surfaces, due to surface-immobilized heparin. The platelet adhesion demonstrated that platelets reacted only minimally with the heparin-containing block copolymers in the test system and that the heparin-containing block copolymers seemed to passify the surface as compared to control surfaces. In the ex vivo A-A shunt experiments, which were carried out under low flow and low shear conditions, the heparin-containing block copolymers exhibited prolonged occlusion times, indicating the ability of the heparin-containing block copolymers to reduce thrombus formation at the surface.  相似文献   
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