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排序方式: 共有538条查询结果,搜索用时 15 毫秒
1.
Alkhateib Y. Gaafar Hirofumi Yamashita Indah Istiqomah Yasuhiko Kawato Kanae Ninomiya Abdelgayed Younes Toshihiro Nakai 《Microscopy research and technique》2020,83(8):979-987
The practical difficulty of parenteral application of fish vaccines against devastating fish diseases diverted the interest toward oral vaccination. Search for effective methods to enhance the oral uptake of viral and bacterial vaccines is continuing. The current research focus on a new role of mucosal fish vaccine adjuvants inducing the antigen uptake by enhancing vascularity or increasing intestinal permeability. Some inflammatory substances cause reversible pathology to the intestinal epithelium, which could be employed for the transepithelial passage of vaccine particles. The natural inflammatory substances used were capsaicin, piperine, and okadaic acid as 1 mg, 2 mg, and 1 μg/fish, respectively. Two inactivated vaccines were used as antigens to test the effect of these inflammatory substances in two different fish hosts. Tested vaccines were inactivated redspotted grouper nervous necrosis virus vaccine in sevenband grouper (Epinephelus septemfasciatus) and inactivated Edwardsiella tarda vaccine in red sea bream (Pagrus major) fish models. The inflammatory substances and each vaccine were anally intubated to fish. Capsaicin proved to be effectively aiding the transepithelial passage of vaccine particles more than piperine, while okadaic acid had no detectable effect. 相似文献
2.
Seiji Inaba Yasuhiko Benino Shinji Kohara Hideo Hosono Setsuro Ito 《Journal of the American Ceramic Society》2020,103(6):3631-3641
Orientation anisotropy, which is well known in organic polymers with appropriate network structures, is less common in oxide glasses. We present the intermediate-range order in anisotropic alkali metaphosphate glass which consists of oriented PO4 tetrahedral chains and intervening alkali cations along the elongation direction. The X-ray total structure factor S(Q) indicates that the inter-chain spacing depends on the size of alkali cations and varies from 5.03 to 6.28 Å. The mixed alkali effect is primarily related to an increase of the separation. The total correlation function T(r) provides the first definite evidence that the anisotropic structure is composed of phosphorus-bridging oxygen bonds (P–OB) lying along the elongation direction and phosphorus-non-bridging oxygen bonds (P–OT) oriented perpendicular to the elongation direction. The present result unveils fundamental aspects of the anisotropic structure of an oxide glass and provides essential information for the development of oxide glasses to control structural anisotropy. 相似文献
3.
Mizuki Tsuta Yasuhiko Sasaki Ikuo Takeuchi Hideki Nakamoto Jun Ishikawa Susumu Kawasaki Junichi Sugiyama Kaori Fujita Masatoshi Yoshimura Mario Shibata Mito Kokawa 《LWT》2014
Flow cytometry (FCM) and aerobic plate count (APC) by the culture method were performed on green tea samples spiked with Escherichia coli type strain NCTC9001 (ATCC11775) solutions of different concentrations. In FCM, fluorescence signals from multiple stained bacteria and other fluorophores are detected using detector channels, and recorded as events with a voltage at each channel. FCM data were analyzed in two ways: conventional and multivariate analysis. In the former, the number of events with voltages larger than the defined threshold values was regarded as the predicted APC. In the latter, voltage histograms of all channels were obtained and merged horizontally to serve as explanatory variables. Then a partial least squares regression (PLSR) model was built to predict APC from the histogram data. The coefficient of determination (R2) and the root mean square error (RMSE) between APC by the culture method and that predicted by conventional FCM were 0.916 and 1.08 cfu/ml2. The APC values predicted by the PLSR model and those measured were in good agreement with R2 of 0.982 and RMSE of 0.417 cfu/ml, which verified the potential of the proposed method for improving APC prediction accuracy by FCM. 相似文献
4.
Abstract A method of describing centrosymmetric gratings (radial, circular and spiral) is presented. The moiré-fringe profile produced by centrosymmetric gratings is analysed using polar coordinates. The concept of the angle of intersection for two superimposed gratings is examined and it is shown how from this study moiré patterns formed from centrosymmetric gratings can be analysed automatically by digital computer. Examples of theoretically predicted patterns, generated by the proposed procedure, are compared with actual moiré-fringe patterns. This method provides for the first time a procedure that can be used in engineering for improving the contrast of moiré patterns and for sharpening these patterns. 相似文献
5.
6.
Takuya Isomura Akimasa Takeuchi Kenta Shimba Kiyoshi Kotani Yasuhiko Jimbo 《Electrical Engineering in Japan》2014,187(4):42-50
Recently, there has been abundant research using multineuron recording, but there are many problems with extracting the features from the obtained spike time series, which are huge in volume and complex. Here we introduce a new method of estimating synaptic connection strengths between neurons by fitting to the Izhikevich model by maximum likelihood estimation. We demonstrate that our method can estimate connection strengths from spike time series given by a simulated neural ensemble and can estimate nonconnectivity between two independent cultured neuronal networks. These results suggest that our method is applicable to network and plasticity analysis of neuronal networks. 相似文献
7.
8.
Dynamic deformation measurement with a large deformation is effectively performed by using virtual speckle patterns. The virtual
speckle pattern has been generally produced by using the operation based on Fourier transform. However, it takes a long calculating
time to produce a virtual speckle pattern, because the method requires Fourier transform operation at each pixel of CCD. In
the proposed method, virtual speckle patterns are produced by Carré algorithm without any operation by Fourier transform.
The method is applied to the in-plane deformation measurement in this paper. As the results, it is confirmed that the calculating
cost of virtual speckle patterns is improved remarkably, and that the measurement accuracy of the new method is also equal
to the ordinary methods. It is also confirmed that the proposed method will expand the use of the speckle interferometry based
on virtual speckle pattern technology. 相似文献
9.
Takahiro Mise Shin Tajima Tatsuo Fukano Kazuo Higuchi Tsukasa Washio Kazuo Jimbo Hironori Katagiri 《Progress in Photovoltaics: Research and Applications》2016,24(7):1009-1015
We have investigated the influence of sodium (Na) on the properties of co‐evaporated Cu2ZnSnS4 (CZTS) layer microstructures and solar cells. The photovoltaic performance and diode properties were improved by incorporating Na from NaF layers into the CZTS layers, while Na had a negligible effect on the microstructural properties of the layer. The best cell fabricated by using an optimal CZTS layer (Cu/(Zn + Sn) = 0.70, Zn/Sn = 1.8) yielded an active area efficiency of 5.23%. The analysis of device properties suggests that charge‐carrier recombination at CZTS/CdS interface is suppressed by intentional Na incorporation from NaF layers. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
10.
Noriyasu Kobayashi Souichi Ueno Satoshi Nagai Makoto Ochiai Noboru Jimbo 《Nuclear Engineering and Design》2011,241(12):4643-4648
We confirmed the defect detection performances of the remote field eddy current testing (RFECT) in order to inspect the helical-coil-type double wall tube steam generator (DWTSG) with the wire mesh layer for the new small fast reactor 4S (Super-Safe, Small and Simple). As the high sensitivity techniques, we tried to increase the direct magnetic field intensity in the vicinity of the inner wall of the tube and decrease the direct magnetic field around the central axis of the tube using the exciter coil with the flux guide made of the iron–nickel alloy. We adopted the horizontal type multiple detector coils with the flux guides arrayed circumferentially to enhance the sensitivity of the radial component. According to the experimental results, the output voltage of the detector coil in the region of indirect magnetic field increased more than 100 times by the application of the exciter and detector coils with the flux guides. Finally, we were able to detect the small hole defect of 1 mm in diameter and 20% of the outer tube thickness in depth over the wire mesh layer by the adoption of the exciter coil and horizontal type multiple detector coils with the flux guides. We also confirmed that the RFECT probe is useful for detecting thinning defects. These experimental results indicated that there is the possibility that we can inspect the double wall tube with the wire mesh layer using the RFECT. 相似文献