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排序方式: 共有1792条查询结果,搜索用时 15 毫秒
971.
Yuko Yoshimura Takashi Ikeda Chiaki Hasegawa Kyung-Min An Sanae Tanaka Ken Yaoi Sumie Iwasaki Daisuke N. Saito Hirokazu Kumazaki Hirotoshi Hiraishi Mitsuru Kikuchi 《International journal of molecular sciences》2021,22(5)
(1) Background: Atypical auditory perception has been reported in individuals with autism spectrum disorder (ASD). Altered auditory evoked brain responses are also associated with childhood ASD. They are likely to be associated with atypical brain maturation. (2) Methods: This study examined children aged 5–8 years old: 29 with ASD but no intellectual disability and 46 age-matched typically developed (TD) control participants. Using magnetoencephalography (MEG) data obtained while participants listened passively to sinusoidal pure tones, bilateral auditory cortical response (P1m) was examined. (3) Results: Significantly shorter P1m latency in the left hemisphere was found for children with ASD without intellectual disabilities than for children with TD. Significant correlation between P1m latency and language conceptual ability was found in children with ASD, but not in children with TD. (4) Conclusions: These findings demonstrated atypical brain maturation in the auditory processing area in children with ASD without intellectual disability. Findings also suggest that ASD has a common neural basis for pure-tone sound processing and language development. Development of brain networks involved in language concepts in early childhood ASD might differ from that in children with TD. 相似文献
972.
Nadja Nijenhuis Daisuke Mizuno Jos A. E. Spaan Christoph F. Schmidt 《Journal of the Royal Society Interface》2012,9(73):1733-1744
Many cells express a membrane-coupled external mechanical layer, the pericellular matrix (PCM), which often contains long-chain polymers. Its role and properties are not entirely known, but its functions are believed to include physical protection, mechanosensing, chemical signalling or lubrication. The viscoelastic response of the PCM, with polysaccharides as the main structural components, is therefore crucial for the understanding of its function. We have here applied microrheology, based on optically trapped micrometre-sized colloids, to the PCM of cultured PC3 prostate cancer cells. This technology allowed us to measure the extremely soft response of the PCM, with approximately 1 µm height resolution. Exogenously added aggrecan, a hyaluronan-binding proteoglycan, caused a remarkable increase in thickness of the viscoelastic layer and also triggered filopodia-like protrusions. The viscoelastic response of the PCM, however, did not change significantly. 相似文献
973.
Radim Zemek Daisuke Anzai Shinsuke Hara Kentaro Yanagihara Ken-ichi Kitayama 《International Journal of Wireless Information Networks》2008,15(3-4):128-136
In target node localization problem, conventional methods based on received signal strength indicator (RSSI) assume a prior knowledge of a channel model and values of its parameters specific for an environment. This limits the conventional localization system to be set up quickly and effectively due to a necessary pre-measurement step to determine both the channel model and the values of its parameters. To address the limitation, a two-stage iterative algorithm which allows to localize a target node without any prior knowledge of the parameter values has been propose. Each stage of the algorithm can be implemented using different estimation methods, such as maximum likelihood (ML) and least square (LS) estimation which provides four different combinations. To determine the best combination, the location estimation performance for all four combinations is evaluated using experimental data collected in measurement campaigns on various indoor locations. The results reveal that the combination of ML estimation method implemented in both stages provides the best location estimation accuracy and the fastest convergence rate. 相似文献
974.
Daisuke Watanabe Yoichi Wada Akira Sasahira Masashi Itori Tetsunari Ebina 《Journal of Nuclear Science and Technology》2017,54(2):182-187
To understand the radiolysis of nitric acid in the volatility condition of nitrous acid, which commonly occurs in a spent fuel reprocessing plant, an irradiation experiment of nitric acid aqueous solution was carried out under a gas flow condition into a solution. In our experiment, the volatilized and dissolved nitrous acid amounts were measured separately. The G-value of nitrous acid generation, evaluated by the total generated nitrous acid amount and the absorbed dose, was consistently about 0.8 molecules/100 eV for 4 mol/L (M) of nitric acid concentration even if the ratio of volatilized nitrous acid to total nitrous acid varied over 50% and the dose rate was varied from 0.13 to 1.2 kGy/h. The dependence of the G-value on the nitric acid concentration was also unaffected by the volatilization of the nitrous acid and was almost equal to the reported values. The highest apparent equilibrium constant of nitrous acid volatilization in our experiment under 50 °C and 4 M of nitric acid concentration was 8.9?×?10?3, which was higher than the reported equilibrium value. It seemed to be caused by the salting-out effect of the nitric acid ions. 相似文献
975.
A steel column that is reinforced by prestressed stays, generally has an increased strength in axial compression. In the past, greater emphasis was placed on obtaining a higher critical buckling load. However, detailed knowledge of the post-buckling behaviour is important to ensure the safety and efficiency of the structure. The current work examines the buckling behaviour of a stayed column with geometrical imperfections, and stress limitation relating to possible material failure. A geometrically nonlinear model accounting for imperfect buckling behaviour of a stayed column was formulated using the Rayleigh–Ritz method, and then validated, using the finite element method. It is shown from these studies that the system tends to be most sensitive to imperfections at a prestress level that yields the highest critical load, and that the real maximum load capacity seems to increase as the prestress increases with a given configuration. The findings suggest that the optimal prestress should be greater than that found from using the previous convention that was based on linear analysis. 相似文献
976.
A steel column that is reinforced by prestressed stays generally has an increased strength in axial compression. In the past, greater emphasis was placed on obtaining its higher critical buckling load. However, detailed knowledge of the post-buckling behaviour is important to ensure the safety and the efficiency of the structure. Although a few studies into the post-buckling behaviour exist, interactive buckling behaviour has never been investigated. As interactive buckling can lead to more dangerous instabilities, the current work examines this for the most popular stayed column configuration using nonlinear finite element analysis. It is shown that interactive buckling becomes the worst case, with a commensurate decrease in the maximum load capacity, where a higher mode governs the critical buckling response. 相似文献
977.
Ferritic stainless steels can be attractive bipolar plate materials of proton exchange membrane fuel cells (PEMFC), provided that the stainless steels show sufficient corrosion resistance, for instance, by eliminating interstitial elements such as carbon and nitrogen. In the present study, thus, ferritic stainless steels (19Cr2Mo and 22Cr2Mo) with extra low interstitials (ELI) are evaluated to determine the required level of chromium content to apply them for PEMFC bipolar plates. In a simulated PEMFC environment (0.05 M SO42− (pH 3.3) + 2 ppm F− solution at 353 K), the 22Cr2Mo stainless steel showed lower current density during the polarization in comparison with the 19Cr2Mo one. The polarization behavior of the 22Cr2Mo stainless steel resembles that of the type 316 one (17Cr12Ni2Mo). Similar values of interfacial contact resistance (ICR) are observed for both ferritic stainless steels. The 22Cr2Mo stainless steel bipolar plate is found to be stable throughout the cell operation, while the 19Cr2Mo stainless steel corroded within 1000 h. After the cell operation, the 22Cr2Mo stainless steel retains the chromium enriched passive film, while the chromium enriched surface film is not found for the 19Cr2Mo one, showing iron oxide/hydroxide based film. X-ray fluorescence (XRF) analysis of the membrane electrode assemblies (MEAs) after the cell operation indicates that the 22Cr2Mo stainless steel was less contaminated with iron species. The above results suggest that the 22Cr2Mo stainless steel can be applicable to bipolar plates for PEMFC, especially 22 mass% of chromium content in ferritic stainless steel with ELI system is, at least, demanded to ensure stable cell performance. 相似文献
978.
Onionin A,a sulfur‐containing compound isolated from onions,impairs tumor development and lung metastasis by inhibiting the protumoral and immunosuppressive functions of myeloid cells
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979.
Cell surface hydrophobicity and colony morphology of Trichosporon asahii clinical isolates
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Tomoe Ichikawa Chihiro Hirata Mizuki Takei Naoyuki Tagami Hiromi Murasawa Reiko Ikeda 《Yeast (Chichester, England)》2017,34(3):129-137
Trichosporon asahii is a pathogenic basidiomycetous yeast. Individual strains of T. asahii have different colony morphologies. However, it is not clear whether cell surface phenotypes differ among the colony morphologies. Here we characterized the cell surface hydrophobicity and analysed the carbohydrate contents of the cell surface polysaccharides in T. asahii clinical isolates with various colony morphologies. Among the three distinctive colony morphologies obtained from one clinical isolate, the white‐type morphology exhibited higher hydrophobicity. The hydrophobicity of heat‐killed T. asahii cells was greatly reduced after periodate oxidation of the cell surface carbohydrates. Furthermore, the cell wall and extracellular polysaccharide components differed among the morphologies. Our results suggest that T. asahii cell surface hydrophobicity is affected by cell surface carbohydrate composition. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
980.
Daisuke Nakamura 《The Annals of Regional Science》2010,45(2):453-471
An integrated framework of the market-area and supply-area systems is applied to four representative hypothetical scenarios to demonstrate the effect of changes in spatially constrained economic factors on firm location. It is initially clarified that there is a mutual mechanism of both types of area in the integrated-framework approach by applying spatial duality theory. The analysis then explores single-center and multi-center models together with a notion of trade-off interaction between agglomeration economies and transportation costs. Finally, the model is extended to a case of the irregular spatial formation of market areas and corresponding supply areas where agglomeration economies are observed. 相似文献