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131.
It is shown that peroxidation of phosphatidylcholine (PC) is enhanced in liver of mice fed a hepatocarcinogenic choline-deficient
diet containing 0.1% w/w ethionine. Mice were divided into 4 groups and fed for 3 weeks one of the following diets: choline-supplemented;
choline-supplemented containing ethionine; choline-deficient; and choline-deficient containing ethionine. Phosphatidylcholine
hydroperoxide (PCOOH) of liver lipids was measured by high performance liquid chromatography using a chemiluminescence detector.
Mice fed a choline-deficient diet containing ethionine showed 6-fold higher PCOOH levels than the choline-supplemented control
mice: the PCOOH/PC molar ratios of liver lipids were 32.3×10−5 and 5.6×10−5, respectively. In addition to this remarkable degree of lipid peroxidation in liver of mice fed the choline-deficient diet
containing ethionine, we also observed a significant liver fatty infiltration, a decrease in plasma and liver α-tocopherol,
and an increase in liver injury-indicative enzyme activities. Also, marker enzymes for hepatocarcinogenesis, glucose-6-phosphatase
and γ-glutamyl transpeptidase were affected. These data suggest that enhanced hydroperoxidation of phosphatidylcholine may
participate in hepatocarcinogenesis provoked by choline deficiency in the presence of ethionine. 相似文献
132.
Hiromi Yoshida Yuka Tomiyama Masayuki Saiki Yoshiyuki Mizushina 《Journal of the American Oil Chemists' Society》2007,84(11):1031-1038
The positional distribution of fatty acids (FA) of triacylglycerols (TAG) and major phospholipids (PL) prepared from four
cultivars of peas (Pisum sativum L.) were investigated as well as their tocopherol contents. The lipids extracted from these peas were separated by thin-layer
chromatography (TLC) into seven fractions. The major lipid components were PL (52.2–61.3%) and TAG (31.2–40.3%), while the
other components were also present in minor proportions (5.6–9.2%). γ-Tocopherol was present in the highest concentration,
and α- and δ-tocopherols were very small amounts. The main PL components isolated from the four cultivars were phosphatidylcholine
(42.3–49.2%), followed by phosphatidylinositol (23.3–25.2%) and then phosphatidylethanolamine (17.7–20.5%). Small but significant
differences (P < 0.05) in FA distribution existed when different pea cultivars were determined. However, the principal characteristics of
the FA distribution in the TAG and the three PL were evident among the four cultivars; unsaturated FA were predominantly located
in the sn-2 position, and saturated FA primary occupied the sn-1 or sn-3 position in the oils of the peas. These results suggest that the regional distribution of tocopherols and fatty acids in
peas is not dependent on the climatic conditions and the soil characteristics of the cultivation areas during the growing
season. 相似文献
133.
134.
Lawanwong Komgrit Hamasaki Hiroshi Hino Ryutaro Yoshida Fusahito 《The International Journal of Advanced Manufacturing Technology》2020,106(5):1855-1867
The International Journal of Advanced Manufacturing Technology - This paper presents a novel technology called ‘double-action bending (DAB)’ to eliminate springback in hat-shape forming... 相似文献
135.
Takayanagi J. Nishizawa N. Sugiura T. Yoshida M. Goto T. 《Quantum Electronics, IEEE Journal of》2006,42(3):287-291
We present an all-fiber system for generating pedestal-free 22-fs ultrashort pulses with a single-peak spectrum. High-power Raman soliton pulses and a normally dispersive highly nonlinear fiber are used to generate a smooth, broadened single-peak spectrum. Then, the higher order dispersion is compensated for using a hybrid fiber composed of a reverse-dispersion fiber and a standard single-mode fiber, which allows pedestal-free ultrashort pulses to be successfully generated. To our knowledge, this is the first demonstration of pedestal-free 20-fs-class ultrashort pulse generation without spectral distortion using an all-fiber configuration. 相似文献
136.
Creation of Superhydrophobic Electrospun Nonwovens Fabricated from Naturally Occurring Poly(Amino Acid) Derivatives 下载免费PDF全文
Hiroaki Yoshida Doris Klee Martin Möller Mitsuru Akashi 《Advanced functional materials》2014,24(40):6359-6364
Creation of superhydrophobic materials bio‐inspired by nature fascinates many scientists. One of the most intriguing challenges in this field is the fabrication of these materials using biopolymers from the viewpoint of green chemistry and environmental chemistry. Here, superhydrophobic and biodegradable nonwovens are constructed by electrospinning from a naturally occurring poly(amino acid), poly(γ‐glutamic acid) (γ‐PGA), modified with a hydrophobic α‐amino acid, l ‐phenylalanine. The contact angle of a water droplet on the materials is 154°, and the droplet remains stuck to the material surface even if it is inverted, clearly indicating a petal‐type superhydrophobic property. Biodegradability and post‐functionalization of the nonwovens as well as cell adhesion on the superhydrophobic materials are also evaluated. As far as we know, this is the first report on biodegradable materials exhibiting a petal‐type superhydrophobicity. The material design and processing shown here can be applied to various bioresources and such functional materials will become a new class of functional materials satisfying some of the requirements in green science. 相似文献
137.
Kakimoto S. Nakajima Y. Sakakibara Y. Watanabe H. Takemoto A. Yoshida N. 《Quantum Electronics, IEEE Journal of》1990,26(9):1460-1466
The low threshold current of 9 mA, the high side-mode suppression ratio of more than 45 dB, the extremely narrow spectral linewidth of 1.1 MHz, and the low chirping of 2.8 Å at -20 dB at 2 Gb/s nonreturn to zero (NRZ) modulation have been achieved in the multiple quantum well (MQW) distributed feedback (DFB) p-substrate partially inverted buried heterostructure (PPIBH) laser diode. The spectral linewidth of 1.1 MHz is the narrowest value among 300-μm-length solitary laser diodes. These results suggest that the MQW-DFB laser diodes are a promising light source for longer distance and higher bit-rate optical communication systems and coherent optical communication systems 相似文献
138.
Yuji Yoshie Masanori Ishizuka Guoqing Guan Chihiro Fushimi Atsushi Tsutsumi 《Advanced Powder Technology》2013,24(2):487-494
A novel method for directly measuring the temperature history of mobile hot ferromagnetic particles (steel particles), substituting for reacting particles, in a binary-solid (reacting particles and inert particles) downflow is introduced. The temperature history of the hot steel particles can be obtained by measuring the temperature of the particles at different axial positions using magnetic fields that can separate the steel particles from other bed materials immediately and easily. Employing the magnetic marking method, magnetic sensors were used to detect the change in magnetic flux density in a given magnetic field, and the residence time of the steel particles was also measured. The cross-sectional averaged particle-to-bed heat transfer coefficients were calculated from the experimental results using simple heat balance equations. The measured temperature data have a relatively wide error range; however, the average temperature curves derived from the average particle-to-bed heat transfer coefficients agreed with the temperature plots. Therefore, the experimental method of this study is applicable to the measurement of the particle temperature in a binary-solid downflow. The results showed that there is strong correlation between the particle-to-bed heat transfer coefficients and normalized collision frequency under the laminar gas flow conditions. 相似文献
139.
Jun Oshitani Tetsuya Kawahito Mikio Yoshida Kuniaki Gotoh George V. Franks 《Advanced Powder Technology》2012,23(1):27-30
In this study, the influence of the fluidized bed height on the float–sink of different sized spheres in a gas–solid fluidized bed was investigated. Fluidized beds with heights h = 200, 150, 100 and 50 mm were prepared using a cylindrical column of inner diameter = 290 mm and a mixture of zircon sand and iron powder as the fluidized medium. Float–sink experiments were carried out using density adjusted spheres of diameter Dsp = 40, 30, 20 and 10 mm. It was found that the float–sink performance at Dsp ?20 mm is not affected by the height of the bed, and the sharpness of separation (the density range where spheres neither float nor sink completely) is less than or equal to 200 kg/m3. In the case of Dsp = 10 mm, the sharpness of separation is a larger value (1100 kg/m3 at h = 200 mm), whereas it decreases with decreasing h and is 400 kg/m3 at h = 50 mm. The fluctuation of the surface height of the fluidized bed was visually recorded. The fluctuation is reduced by reducing h. The fluctuation vs. h correlates with the sharpness of separation at Dsp = 10 mm vs. h. These results indicate that the dry float–sink separation of smaller sized spheres is improved as the fluctuation of fluidized bed surface is decreased by reducing the fluidized bed height. 相似文献
140.
Deformability enhancement in ultra-fine grained, Ar-contained W compacts by TiC additions up to 1.1%
S. Matsuo H. Kurishita H. Arakawa T. Takida M. Kato Y. Yamamoto K. Takebe M. Kawai N. Yoshida 《Materials Science and Engineering: A》2008,492(1-2):475-480
Nano-sized Ar bubbles give negative influence on the fracture resistance and occurrence of superplasticity in ultra-fine grained (UFG) W–TiC compacts. In order to enhance deformability in UFG, Ar-contained W–TiC compacts, effects of TiC addition on the high-temperature deformation behavior were examined. W–TiC compacts with TiC additions of 0, 0.25, 0.5, 0.8 and 1.1 wt% were fabricated by mechanical alloying in a purified Ar atmosphere and hot isostatic pressing. Tensile tests were conducted at 1673–1973 K (0.45–0.54 Tm, Tm: melting point of W) at initial strain rates from 5 × 10−5 to 5 × 10−3 s−1. It is found that as TiC addition increases, the elongation to fracture significantly increases, e.g., from 3 to 7% for W–0 and 0.25TiC/Ar to above 160% for W–1.1TiC/Ar when tested at 1873 and 1973 K at 5 × 10−4 s−1. The flow stress takes a peak at 0.25%TiC and decreases to a nearly constant level at 0.5–1.1%TiC. The ranges of the strain rate sensitivity of flow stress, m, and the activation energy for deformation, Q, with TiC additions are 0.17–0.30 and 310–600 kJ/mol, respectively. The observed effects of the TiC additions on the tensile properties are discussed. 相似文献