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21.
Optical path-length matrix method for estimating skin spectrum 总被引:2,自引:0,他引:2
Satoshi Yamamoto Izumi Fujiwara Midori Yamauchi Norimichi Tsumura Keiko Ogawa-Ochiai 《Optical Review》2012,19(6):361-365
In this article, we propose a new method??the optical path-length matrix method (OPLM)??as a faster alternative to the Monte Carlo for multi-layered media (MCML), which is often used to simulate the skin spectrum. Theoretically, peripheral oxygen saturation can be estimated by iterating MCML, but it is not a realistic strategy because it requires huge computation time. The optical path-length matrix is obtained as the probabilistic density histograms of the optical path length in skin using MCML, and once the matrix is obtained, skin spectral reflectance can be calculated by accumulating all combinations of elements in the matrix and by setting an absorption coefficient based on the Beer-Lambert law. The computational time of OPLM was approximately 26,000 times faster than that of MCML. 相似文献
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Masaru Takeya Takehiro Matsuda Masao Iwamoto Norimichi Tsumura Toshiya Nakaguchi Yoichi Miyake 《Optical Review》2007,14(2):97-104
We propose a technique for estimating gene expression values for duplicated data on cDNA microarrays. In the scatter plots,
the distribution is constructed from a mixture of normal two-dimensional distributions, which represent fluctuations in gene
expression values due to noise. An expectation-maximization (EM) algorithm is used for estimating the modeling parameters.
The probability that duplicated data is shifted by noise is calculated using Bayesian estimation. Six data sets of rice cDNA
microarray assays were used to test the proposed technique. Genes in the data sets were subjected to clustering based on probability
of true value. Clustering successfully identified candidate genes regulated by circadian rhythms in rice. 相似文献
25.
On perturbations of M-accretive operators in Banach spaces 总被引:1,自引:0,他引:1
Norimichi Hirano A. K. Kalinde 《Proceedings of the American Mathematical Society》1996,124(4):1183-1190
In this paper, we consider the solvability of nonlinear equations of the form
where is an m-accretive operator on a Banach space , is a mapping on and .
26.
Morita H Ishioka N Takatsu H Shinzato T Obara Y Nakahata N Kobayashi J 《Organic letters》2005,7(3):459-462
[structure: see text] Two novel alkaloids with an unprecedented fused-pentacyclic skeleton, daphmanidins C (1) and D (2), have been isolated from the leaves of Daphniphyllum teijsmanii, and the structures were elucidated on the basis of spectroscopic data. The relative stereochemistry of 1 and 2 was assigned by combination of NOESY correlations and a simulation analysis. Daphmanidin C (1) elevated activity of NGF biosynthesis. 相似文献
27.
Kajiwara T Nakano M Kaneko Y Takaishi S Ito T Yamashita M Igashira-Kamiyama A Nojiri H Ono Y Kojima N 《Journal of the American Chemical Society》2005,127(29):10150-10151
A unique "single-chain quantum magnet" was formed by an alternating arrangement of high-spin FeII/low-spin FeIII ions. Although the predominant spin-carrier components (high-spin FeII) possess easy-plane magnetic anisotropy (D > 0), twisted arrangement of easy-planes along the chain axis defines a novel class of one-dimensional Ising system. 相似文献
28.
Takeshi Koishi Mai Sasaki Toshiya Nakaguchi Norimichi Tsumura Yoichi Miyake 《Optical Review》2010,17(2):54-60
We propose a practical and simple measurement function of three dimensional (3D) length for endoscopy based on triangulation
using manually pointed correspondences. This system is a novel combination of conventional methods. 3D length information
is useful for many medical purposes and the burden of manual procedures can be reduced by focusing on length. We employed
a novel combination for length measurement, that is, a monocular endoscope with an electromagnetic tracking sensor. The proposed
method can measure the length without any equipment for light projection and changing the current procedure of endoscopy.
Our method is made more robust and reliable than the automatic correspondence techniques through the best use of the expertise
of endoscopists. We developed a prototype system and evaluated its accuracy. From experimental results, we showed that the
proposed method can measure the 3D length of static objects accurately as long as the measurement geometry is suitable. 相似文献
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Takenaka N Tanaka M Okitsu K Bandow H 《The journal of physical chemistry. A》2006,110(36):10628-10632
Oxidative decomposition of gallic acid occurs in alkaline solutions but hardly arises in acidic solutions. We have found that the addition of sodium chloride promotes the decomposition of gallic acid caused by freezing even under neutral and acidic conditions. Even at pH 4.5, gallic acid was decomposed by freezing in the presence of NaCl; however, in the absence of NaCl, it was hardly decomposed by freezing at pH lower than 7. Chloride ions are more easily incorporated in ice than sodium ions when the NaCl solution is frozen. The unfrozen solution in ice becomes positively charged, and as a result, protons transfer from the unfrozen solution to the ice. We measured the pH in the unfrozen solution which coexists with single-crystal ice formed from a 5 mmol dm(-3) NaCl solution and determined the pH to be 8.6 at equilibrium with CO(2) of 380 ppm or 11.3 in the absence of CO(2) compared to pH 5.6 in the original solution. From the model calculation performed for gallic acid solution in the presence of 5 mmol dm(-3) NaCl, it can be estimated that the amount of OH(-) transferred from the ice to the solution corresponds to 1.26 x 10(-5) mol dm(-3). The amount of OH(-) transferred is concentrated into the unfrozen solution and affects the pH of the unfrozen solution. Therefore, the pH in an unfrozen gallic acid solution in ice becomes alkaline, and the decomposition of gallic acid proceeds. It is expected that other base-catalyzed reactions in weakly acidic solutions also proceed by freezing in the presence of NaCl without the need for any alkaline reagents. 相似文献