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排序方式: 共有853条查询结果,搜索用时 437 毫秒
1.
Tomohiro Toigawa Yasuhiro Tsubata Takeshi Kai Takuya Furuta Yuta Kumagai Tatsuro Matsumura 《溶剂提取与离子交换》2021,39(1):74-89
ABSTRACT Absorbed-dose estimation is essential for evaluation of the radiation tolerance of minor-actinide-separation processes. We propose a dose-evaluation method based on radiation permeability, with comparisons of heterogeneous structures seen in the solvent-extraction process, such as emulsions forming in the mixture of the organic and aqueous phases. A demonstration of radiation-energy-transfer simulation is performed with a focus on the minor-actinide-recovery process from high-level liquid waste with the aid of the Monte Carlo radiation-transport code PHITS. The simulation results indicate that the dose absorbed by the extraction solvent from alpha radiation depends upon the emulsion structure, and that from beta and gamma radiation depends upon the mixer-settler-apparatus size. Non-negligible contributions of well-permeable gamma rays were indicated in terms of the plant operation of the minor-actinide-separation process. 相似文献
2.
Abidur Rahman Makoto Kobayashi Kotaro Sugimoto Yuta Endo Manabu Kojima Shigenori Furukawa Takafumi Watanabe Shu Soeda Yuko Hashimoto Keiya Fujimori Hideki Chiba 《International journal of molecular sciences》2021,22(7)
Background: Within the claudin (CLDN) family, CLDN12 mRNA expression is altered in various types of cancer, but its clinicopathological relevance has yet to be established due to the absence of specific antibodies (Abs) with broad applications. Methods: We generated a monoclonal Ab (mAb) against human/mouse CLDN12 and verified its specificity. By performing immunohistochemical staining and semiquantification, we evaluated the relationship between CLDN12 expression and clinicopathological parameters in tissues from 138 cases of cervical cancer. Results: Western blot and immunohistochemical analyses revealed that the established mAb selectively recognized the CLDN12 protein. Twenty six of the 138 cases (18.8%) showed low CLDN12 expression, and the disease-specific survival (DSS) and recurrence-free survival rates were significantly decreased compared with those in the high CLDN12 expression group. We also demonstrated, via univariable and multivariable analyses, that the low CLDN12 expression represents a significant prognostic factor for the DSS of cervical cancer patients (HR 3.412, p = 0.002 and HR 2.615, p = 0.029, respectively). Conclusions: It can be concluded that a reduced CLDN12 expression predicts a poor outcome for cervical cancer. The novel anti-CLDN12 mAb could be a valuable tool to evaluate the biological relevance of the CLDN12 expression in diverse cancer types and other diseases. 相似文献
3.
Jun Ogata Kentaro Hirao Kenya Nishioka Arisa Hayashida Yuanzhe Li Hiroyo Yoshino Soichiro Shimizu Nobutaka Hattori Yuzuru Imai 《International journal of molecular sciences》2021,22(7)
Leucine-rich repeat kinase 2 (LRRK2) is a major causative gene of late-onset familial Parkinson’s disease (PD). The suppression of kinase activity is believed to confer neuroprotection, as most pathogenic variants of LRRK2 associated with PD exhibit increased kinase activity. We herein report a novel LRRK2 variant—p.G2294R—located in the WD40 domain, detected through targeted gene-panel screening in a patient with familial PD. The proband showed late-onset Parkinsonism with dysautonomia and a good response to levodopa, without cognitive decline or psychosis. Cultured cell experiments revealed that p.G2294R is highly destabilized at the protein level. The LRRK2 p.G2294R protein expression was upregulated in the patient’s peripheral blood lymphocytes. However, macrophages differentiated from the same peripheral blood showed decreased LRRK2 protein levels. Moreover, our experiment indicated reduced phagocytic activity in the pathogenic yeasts and α-synuclein fibrils. This PD case presents an example wherein the decrease in LRRK2 activity did not act in a neuroprotective manner. Further investigations are needed in order to elucidate the relationship between LRRK2 expression in the central nervous system and the pathogenesis caused by altered LRRK2 activity. 相似文献
4.
A method is proposed to generate categorical colour observer functions (individual colour matching functions) for any field size based on the CIE 2006 system of physiological observer functions. The method combines proposed categorical observer techniques of Sarkar et al with a physiologically-based individual observer model of Asano et al and a clustering technique to produce the optimal set of categorical observers. The number of required categorical observers varies depending on an application with as many as 50 required to predict individual observers' matches when a laser projector is viewed. However, 10 categorical observers are sufficient to represent colour-normal populations for personalized colour imaging. The proposed and recommended categorical observers represent a robust and inclusive technique to examine and quantify observer metamerism in any application of colorimetry. 相似文献
5.
The fracture behaviors of gellan hydrogels under compression remarkably depend on the strain rate as well as the boundary conditions for lateral expansion. In the geometry with no constraint for lateral expansion (conventional uniaxial compression), the gels rupture at relatively small strains independently of the compression rates. In contrast, when the gels are compressed extremely slowly (at a strain rate of ca. 10−5 s−1) in the geometry prohibiting the lateral expansion at their top and bottom surfaces, they are remarkably compressible down to 2% of the initial height without macroscopic fracture and they are accompanied by a large amount of water release. In such markedly compressed gels, many microscopic cracks are formed around the central layer, where strain concentration occurs due to the nonuniform deformation arising from the constrained geometry. In the highly compressible case, the formation of macroscopic cracks is prevented by the localization of microscopic cracks as well as the enhancement in mechanical toughness by a significant increase in polymer concentration due to water release. 相似文献
6.
In the fiber Bragg grating sensing using a superluminescent diode as the light source and an arrayed waveguide grating as the wavelength interrogator, the wavelength measurement error due to the spectral modulation of the superluminescent diode is theoretically formulated and quantitatively analyzed by computer simulation. It is shown that the wavelength measurement errors produced with the use of real superluminescent diodes are in very good agreement with the theoretical results. In order to reduce the wavelength measurement error due to the spectral modulation of superluminescent diode, two different types of remedies are proposed that utilize the temperature switching of superluminescent diode and that adjust the bandwidths of fiber Bragg grating and arrayed waveguide grating, and their efficacies are experimentally demonstrated together with good quantitative agreement with the theoretical calculation. 相似文献
7.
J. Okabayashi M. Watanabe H. Toyao T. Yamaguchi J. Yoshino 《Journal of Superconductivity and Novel Magnetism》2007,20(6):443-446
We have investigated the current pulse width dependence on current-driven magnetization reversal in double-barrier structures
using GaMnAs-based magnetic tunneling junctions (MTJ) in order to clarify the origin of low threshold current density for
current-driven magnetization reversal. Comparing with the case of single-barrier MTJ, the pulse-width dependence reveals that
threshold current density is reduced by double-barrier MTJ. We confirmed that the threshold current density in the order of
104 A/cm2 is estimated considering the effect of current pulse width. 相似文献
8.
S Yoshino 《Canadian Metallurgical Quarterly》1996,48(7):702-705
Foliar application of cytozyme to 30-day-old black-gram plants resulted 48% increase of dry matter accumulation. The increase in fresh and dry weights of total plants was largely due to enhanced CO2 assimilation rates which were associated with increased RuBP carboxylase activities. The photochemical characteristics in the isolated chloroplasts exhibited an increase of 32, 28 and 40%, measured as the photoreduction of DCPIP, FeCN and NADP, respectively. Cytozyme treatment also resulted an increase in the chlorophyll content in leaves. 相似文献
9.
Fukuda H. Ebara M. Kobayashi A. Sugiura N. Yoshikawa M. Saisho H. Kondo F. Yoshino S. Yahagi T. 《IEEE transactions on bio-medical engineering》1998,45(3):396-400
To objectively evaluate the parenchymal echo pattern of cirrhotic liver and chronic hepatitis, the authors applied an image analyzing system (IAS) using a neural network. Autopsy specimens in a water tank (n=13) were used to examine the relationship between the diameter of the regenerative nodule and the coarse score (CS) calculated by IAS. CS was significantly correlated with the diameter of the regenerative nodule (p<0.0001, r=0.966). CS is considered to be useful for evaluating the coarseness of the parenchymal echo pattern 相似文献
10.
Lee S.B. Nakayama K. Matsui T. Ozaki M. Yoshino K. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2002,9(1):31-38
Silica particles dispersed in liquid crystals exhibit a novel behavior such as a unique migrating behavior and alignment. These characteristics are found to depend on the size of the nanoparticles, the surface state of nanoparticles, the liquid crystal (LC) phases, the amplitude and the frequency of applied voltage. These are discussed in terms of anisotropic particle-particle and particle-LC molecules interactions in the anisotropic environment of liquid crystal matrix 相似文献