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221.
Gap junctions play an important role in differentiation of odontoblasts. Gap junction protein, connexin 43 is expressed in odontoblast. However, the detailed localization in odontoblasts has yet to be fully investigated. We investigated the localization of connexin43 in rat odontoblasts immuno‐electron microscopically. The rats were transcardially fixed with 1% paraformaldehyde in 0.1M phosphate buffer, and mandibles were decalcified with 10% ethylenediamine tetraacetic acid. Pre‐embedding method was carried out for immuno‐electron microscopic analysis. Microscopically, gap junctions were localized between bodies of odontoblasts, and between bodies and processes of odontoblasts. The gap junctions were labeled with gold particles that indicated connexin43. These results suggest that gap junctions between odontoblasts are definitely composed of connexin43 in rats, and our methods used in this study is useful to investigate localization of connexin43 immuno‐electron microscopically. Microsc. Res. Tech., 76:988–991, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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Nearest neighbor search in high‐dimensional spaces is an interesting and important problem which is relevant for a wide variety of applications, including multimedia information retrieval, data mining, and pattern recognition. For such applications, the curse of high dimensionality tends to be a major obstacle in the development of efficient search methods. This paper addresses the problem of designing an efficient algorithm for high‐dimensional nearest neighbor search using a priority queue. The proposed algorithm is based on a simple linear search algorithm and eliminates unnecessary arithmetic operations from distance computations between multidimensional vectors. Moreover, we propose two techniques, a dimensional sorting method and a PCA‐based method, to accelerate multidimensional search. Experimental results indicate that our scheme scales well even for a very large number of dimensions. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 164(3): 69–77, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20502  相似文献   
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A slider surface analyzing tester was developed to observe the lubricant thickness distribution on a slider surface by interferometry. We observed three phenomena related to lubricant pickup by the slider. The picked-up lubricant gathered around the boundary of the pad and recess area during the unloading interval, and the gathered lubricant flowed to the trailing edge of the pad after loading on the disk surface. There were two lubricant flows on the pad surface. The first was a circulation flow from the dynamic flying height protrusion area to the leading edge of the pad. The second was a circulation flow from the lubricant pool to the leading edge of the pad. Lubricant dewetting occurred on the slider pad surface when a thick layer of lubricant was adhered to the pad surface.  相似文献   
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The conditions for the generation of nano-sized Au agglomerates in Si, which were recently discovered by the author, have been investigated. The agglomerates can be generated under very limited conditions. The agglomerates are generated with a continuous annealing method but are not generated with a typical ordinary annealing method. They are generated at an annealing temperature of 900 °C but not at 930 °C. Agglomerates are not generated in regions less than 6 μm from the surface. They are generated in a sample that is initially supersaturated with Au atoms at 7.5 × 1016 cm?3 but are only generated at the boundary of the out-diffusion in a sample that initially contains Au atoms at 2.5 × 1016 cm?3. Generation of the agglomerates becomes difficult as the time to cool to the annealing temperature increases in the continuous annealing process. The generated agglomerates dissolve and disappear as the surrounding Au concentration decreases to the thermal equilibrium value, that is, as the sample recovers from the supersaturation of the surrounding Au.  相似文献   
228.
To understand the correlation between foamability and melt rheology of polyethylene-based ionomers having different degrees of the neutralization and corresponding nano-composites, we have conducted the foam processing via a batch process in an autoclave and microcellular foam injection molding (FIM) process using the MuCell® technology. We have discussed the obtainable morphological properties in both foaming processes. All cellular structures were investigated by using field emission scanning electron microscopy. The competitive phenomenon between the cell nucleation and the cell growth including the coalescence of cell was discussed in light of the interfacial energy and the relaxation rate as revealed by the modified classical nucleation theory and rheological measurement, respectively. The FIM process led to the opposite behavior in the cell growth and coalescence of cell as compared with that of the batch process, where the ionic cross-linked structure has significant contribution to retard the cell growth and coalescence of cell. The mechanical properties of the structural foams obtained by FIM process were discussed.  相似文献   
229.
The mineralogical alteration of bentonite was studied in saline water at 60 and 90 °C. To obtain the altered bentonite, a crude bentonite (Kunigel V1) was dispersed into simulated sea-water, and maintained at 60 or 90 °C over 6000 h. Magnesium was accumulated into bentonite during the experiments at levels over the cation exchange capacity (CEC; 0.78 meq/g for the original bentonite) at only 90 °C. The excess Mg was not replaced by ammonium ions, suggesting that the precipitation of Mg solid in bentonite occurred. The IR spectra and the thermogravimetric/differential Thermal Analysis (TG-DTA) profiles show the neo-formation of magnesium hydroxide in the altered bentonite. The CEC decreased from 0.78 to 0.45 meq/g as the amount of accumulated Mg increased. The distribution coefficient Kd for Cs in the altered bentonite was half of that in the original bentonite. It is conjectured that the thermal alteration of bentonite in saline water affects the sorption capacity of Cs onto smectite.  相似文献   
230.
Studies have been made of an electroless copper-nickel-phosphorus alloy from a citrate complex bath using hypophosphite as reducing agent and electroless copper-nickel binary alloy from a triethanolamine complex bath using formaldehyde as reducing agent. With an increase in copper content of alloy, the specific resistance of deposit decreased. The TCR of copper-nickel-phosphorus alloy increased remarkably because of the crystallization of Ni3P after heat treatment. But the increase in TCR of copper-nickel binary alloy was moderate and not so striking as for the phosphorus containing alloy.  相似文献   
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