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51.
52.
Takashi Kanno Changmin Kim Daisuke Yamanaka Ken-ichi Ishibashi Hiroshi Tanaka Naohito Ohno Yoshiyuki Adachi 《International journal of molecular sciences》2021,22(4)
Because Japanese cedar pollen (JCP) contains beta-1,3-d-glucan (BG), there is concern that its lingering presence in the atmosphere, especially during its scattering period, may cause false positives in the factor-G-based Limulus amebocyte lysate (LAL) assay used to test for deep mycosis (i.e., G-test). Hence, we examined whether the LAL assay would react positively with substances contained in JCP by using the G-test to measure JCP particles and extracts. BG was purified from the JCP extract on a BG-specific affinity column, and the percentage extractability was measured using three different BG-specific quantitative methods. The G-test detected 0.4 pg BG in a single JCP particle and 10 fg from a single particle in the extract. The percentage extractability of JCP-derived BG was not significantly different among the three quantitative methods. As the JCP particles should technically have been removed during serum separation, they should be less likely to be a direct false-positive factor. However, given that the LAL-assay-positive substances in the JCP extract were not distinguishable by the three BG-specific quantitative methods, we conclude that they may cause the background to rise. Therefore, in Japan false positives arising from JCP contamination should be considered when testing patients for deep mycosis. 相似文献
53.
Dynamic mechanical properties of three‐component composites (acrylic polymer/epoxy/SiO2) in the glass‐transition region
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Hideyuki Uematsu Takashi Nishimoto Shuichi Tanoue Yoshiyuki Iemoto Yuji Aoki Masataka Sugimoto Kiyohito Koyama 《应用聚合物科学杂志》2014,131(13)
In previous studies, we reported the linear and nonlinear rheological properties of three‐component composites consisting of acrylic polymer (AP), epoxy resin (EP), and various SiO2 contents (AP/EP/SiO2) in the molten state. In this study, the dynamic mechanical properties of AP/EP/SiO2 composites with different particle sizes (0.5 and 8 μm) were investigated in the glass‐transition region. The EP consisted of three kinds of EP components. The α relaxation due to the glass transition shifted to a higher temperature with an increase in the volume fraction (?) for the AP/EP/SiO2 composites having a particle size of 0.5 μm, but the α relaxation scarcely shifted for the composite having a particle size of 8 μm as a general result. This result suggested that the SiO2 nanoparticles that were 0.5 μm in size adsorbed a lot of the low‐glass‐transition‐temperature (Tg) component because of their large surface area. The AP/SiO2 composites did not exhibit a shift in Tg; this indicated that the composite did not adsorb any component. The modulus in the glassy state (E′g) exhibited a very weak &phis; dependence for the AP/EP/SiO2 composites having particle sizes of 0.5 and 8 μm, although E′g of the AP/SiO2 composites increased with &phis;. The AP/EP/SiO2 composites exhibited a peculiar dynamic mechanical behavior, although the AP/SiO2 composites showed the behavior of general two‐component composites. Scanning electron microscopic observations indicated that some components in the EP were adsorbed on the surface of the SiO2 particles. We concluded that the peculiar behavior of the AP/EP/SiO2 composites was due to the selective adsorption of the EP component. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40409. 相似文献
54.
Ruri Hidema Hiroshi Suzuki Shion Hisamatsu Yoshiyuki Komoda 《American Institute of Chemical Engineers》2014,60(5):1854-1862
An experimental study has been performed to investigate the relationship between the extensional viscosity of polymers and the turbulent drag reduction. Self‐standing flowing soap film was used to generate two‐dimensional (2‐D) turbulent flow to eliminate shear stress. Two types of polymers having different flexibilities were added to the 2‐D turbulence. The effects of these polymers were visualized by the interference pattern of flowing soap films. The vortex deformation by adding polymers was analyzed by Fourier transformation and wavelet transformation. The scaling exponents of the power spectrum of interference patterns indicate that the mechanism of turbulence laminarization due to the extensional viscosity is anisotropic. A wavelet analysis reveals the high and low fluctuations of the polymer‐added flow. Results from wavelet analysis indicate disappearing of original vortices, and appearing of new structures in low frequency in 2‐D flow. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1854–1862, 2014 相似文献
55.
We fabricated high performance films using cellulose butyral (CB) synthesized from native cellulose. Two-step reactions were adopted to produce the derivative CB, including etherification of cellulose with glycidol in NaOH/urea aqueous solution to yield O-(2,3-dihydroxypropyl) cellulose (DHPC), and butyralization of DHPC. Both DHPC and CB products were easily processed into a thin film by hot-press molding. The butyral modifier significantly improved the tenacity of highly ductile DHPC, by virtue of the possible chain-entangling action of the ring structures in the stretching process. Thereby the film toughness was markedly enhanced. The CB films exhibited excellent optical transparency and a good adhesive property to glass plates. Thus the films may be comparable to commercial poly(vinyl butyral) (PVB) films in optical and mechanical performances and therefore possess a potential applicability as interlayer for laminated glasses. 相似文献
56.
Li-Ming Sun Ting-Ting Wang Bei-Wei Zhu Hai-Ling Niu Rui Zhang Hong-Man Hou Gong-Liang Zhang Yoshiyuki Murata 《Food science and biotechnology》2013,22(5):1-3
To investigate the relationship between matrix metalloproteinase (MMPs) and autolysis of sea cucumber Stichopus japonicus, the dermis homogenate was incubated at 25°C to induce autolysis. EDTA Na2 and 1,10-phenanthroline were used to verify the effect of MMPs on autolysis, which was measured by soluble protein and protein pattern. Soluble protein level increased during a 6-h autolysis process. SDS-PAGE demonstrated obvious protein degradation with the concomitant occurrence of degradation products. The above two indicators could be inhibited significantly by EDTA Na2 and 1,10-phenanthroline, indicating that MMPs might play a significant role in autolysis of sea cucumber. 相似文献
57.
Takatsuki S Nemoto S Sasaki K Maitani T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(2):89-95
An LC/MS method was developed for the determination of acrylamide (AA) in processed or cooked foods. AA was extracted with a mixture of water and acetone from homogenized food samples after the addition of 13C-labeled acrylamide (AA-1-(13)C) as an internal standard. The extract was concentrated, washed with dichloromethane for defatting, and cleaned up on Bond Elut C18, PSA and ACCUCAT cartridge-columns, and then AA was determined by LC/MS in the selected ion recording (SIR) mode. For the LC/MS analysis, four LC columns were connected in-line and the flow of the mobile phase was switched according to a time-program. Monitoring ions for AA were m/z 72 and 55, and those for AA-1-(13)C were m/z 73 and 56. AA and AA-1-(13)C were determined without interference from the matrices in all samples. The recoveries of AA from potato chips, corn snack, pretzel and roasted tea spiked at the level of 500 ng/g of AA were 99.5-101.0% with standard deviations (SD) in the range from 0.3 to 1.6%. The limits of detection and quantification of the developed method were 9 and 30 ng/g for AA in samples, respectively. The method was applied to the analysis of AA in various processed or cooked food samples purchased from retail markets. High levels of AA were found in potato chips and French-fried potato (467-3,544 ng/g). Fried and sugar-coated dough cakes (karinto) contained 374 and 1,895 ng/g. Corn snacks contained 117-535 ng/g of AA. Roasted foods (such as roasted sesame seed, roasted barley (mugi-cha), roasted tea (hoji-cha), coffee beans and curry powder) contained 116-567 ng/g of AA. Foods made from fish, egg and meat contained lower levels of AA than the plant-based foods. Foods containing much water showed a tendency to have low levels of AA compared with dry foods. The proposed method was applicable to the analysis of AA in variety of processed foods. 相似文献
58.
Yoshiyuki Ohiro Hiroshi Ueda Norio Shibata Teruyuki Nagamune 《Journal of Bioscience and Bioengineering》2010,109(1):15-19
We describe a homogeneous competitive immunoassay for a phosphorylated protein antigen. The assay takes advantage of the enhanced fluorescence resonance energy transfer (FRET) technology, which has a unique characteristic that the FRET signal is increased by the specific interaction of two fluorolabeled leucine zippers. We chose extracellular signal-regulated kinase (ERK) as a model antigen and constructed two molecular probes in which either anti-phosphorylation site antibody or the antigen peptide was chemically conjugated to the enhanced FRET probes. While these molecular probes indicated sufficient FRET signal without antigen, they displayed a significant change in the fluorescent spectrum by mixing with phosphorylated antigens. With this competitive enhanced FRET immunoassay, a phosphorylated ERK concentration within the range from 15 nM to 250 nM could be determined. Because the assay is very simple, it would be applied to not only in vitro assay but also in vivo detection of protein phosphorylation. 相似文献
59.
Hydrogen and carbon dioxide adsorption with tetra‐n‐butyl ammonium semi‐clathrate hydrates for gas separations
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Hiroyuki Komatsu Masaki Ota Yoshiyuki Sato Masaru Watanabe Richard L. Smith Jr. 《American Institute of Chemical Engineers》2015,61(3):992-1003
Gas adsorption rates of H2, CO2, and H2‐CO2 gas mixture (H2/CO2 = 3.4) with tetra‐n‐butyl ammonium salt (bromide, chloride, and fluoride) semi‐clathrate hydrate particles were measured at 269 K to assess their properties for gas separation. Equilibrium gas occupancies in the S‐cages of the particles were in order of (high to low) for hexagonal structure‐I, tetragonal structure‐I, and superlattice of cubic structure‐I structures with the maximum fractional occupancy by CO2 being about 40%. The CO2 diffusion rate depended on the anion size of the salt, which is attributed to distortion of the S‐cage that is close to the molecular size of CO2. Simulations of semi‐clathrate hydrate particles with theory showed that H2/CO2 selectivities could be as high as 36 (3.0 mol% TBAF) and that selectivities for an ideal membrane (3.3 mol% TBAF) could be >100 (269 K, 0.3–4.5 MPa). Semi‐clathrate hydrates have wide application as separation media for gas mixtures. © 2014 American Institute of Chemical Engineers AIChE J, 61: 992–1003, 2015 相似文献
60.
Yin Zhang Jianan Ai Dinggai Wang Zhongrong Hong Wenhui Li Yoshiyuki Yokogawa 《Ceramics International》2013
Biphasic calcium phosphate (BCP) bimodal porous ceramics were prepared from a mixture of fine powders of hydroxyapatite (HAp) and beta-tricalcium phosphate (β-TCP) with varying HAp/β-TCP ratios. Two types of HAp powders and one type of β-TCP powder were used to produce porous BCP bioceramics with HAp/β-TCP weight ratios of 20/80, 40/60, and 80/20. Dissolution tests were performed to compare the dissolution properties of BCP-based bioceramics with different structural properties. Porous ceramic samples of approximately 0.5 g were individually soaked in 30 ml of simulated body fluid (SBF) solution at 36.5 °C for 1, 3, 7 and 10 days, respectively. The calcium content of the SBF solution was analyzed by ICP. The porous bodies were filtered, dried, and characterized using SEM, XRD, and FT-IR. The results indicate that the sample structural properties seem to have a greater effect than the storage environment on the dissolution properties. 相似文献