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101.
A novel substrate {Galβ1,4GlcNAcβ1,4GlcNAc-β-pNP [Gal(GlcNAc)2-β-pNP]} for assaying lysozyme activity has been designed using docking simulations and enzymatic synthesis via β-1,4-galactosyltransferase-mediated transglycosylation from UDP-Gal as the donor to (GlcNAc)2-β-pNP as the acceptor. Hydrolysis of the synthesized Gal(GlcNAc)2-β-pNP and related compounds using hen egg-white lysozyme (HEWL) demonstrated that the substrate was specifically cleaved to Gal(GlcNAc)2 and p-nitrophenol (pNP). A combination of kinetic studies and docking simulation was further conducted to elucidate the mode of substrate binding. The results demonstrate that Gal(GlcNAc)2-β-pNP selectively binds to a subsite of lysozyme to liberate the Gal(GlcNAc)2 and pNP products. The work therefore describes a new colorimetric method for quantifying lysozyme on the basis of the determination of pNP liberated from the substrate. 相似文献
102.
Toshiki Tsubota Masaki Morita Sunao Kamimura Teruhisa Ohno 《Journal of Porous Materials》2016,23(2):349-355
Unconventional pretreatment, that is, delignification and the addition of guanidine phosphate, was performed for the synthesis of activated carbon having a high specific surface area from bamboo by physical activation. The values of the specific surface area, total pore volume, and average pore size depended on the amount of added guanidine phosphate and the CO2 activation time. The amount of the added guanidine phosphate under the optimum conditions for the highest specific surface area was much lower than that of the phosphorous acid chemical activator under conventional conditions. The N2 adsorption isotherms of all the samples were type I, which means that micropores were dominant. The pore sizes of the samples in this study were similar to that of the physically-activated carbon. Therefore, the activation process was presumed to be essentially not chemical, but physical. The relation between the yield and the specific surface area improved with the addition of guanidine phosphate. The reason for the improvement may be the change in the reactivity of the carbon material generated during the heating process. The maximum specific surface area was ca. 2000 m2 g?1, which is a high value for a physically-activated carbon. 相似文献
103.
A series of star-shaped poly(lactic acid)s with carboxylic acid terminal groups have been synthesized by direct poly-condensation of lactic acid in the presence of a poly-carboxylic acid core molecule with triphenylphosphonium trifluoromethanesulfonate (TPP-T) catalyst.These star-polymers had thermal properties not very much different from those of star-shaped poly(lactic acid) with hydroxyl terminal groups and linear poly(lactic acid), irrespective of the structure of the core molecule and number of polymer arms. Solubility and degradability of these star-polymers were, however, greatly enhanced compared to those of star-polymers with hydroxyl terminal groups and increased depending on the number of polymer arms. From the star-shaped polymers, a variety of ammonium salts and the corresponding carboxyamides were successfully prepared. 相似文献
104.
105.
Masafumi Yamamoto Makoto Iwasaki Kazuaki Ito Nobuyuki Matsui 《Electrical Engineering in Japan》2010,171(2):31-39
This paper presents a modeling methodology for unknown disturbances in mechatronics systems, based on disturbance estimation using an iterative learning process. In disturbance modeling, nonlinear frictions are specially handled as disturbances in the mechanisms, which mainly degrade trajectory control performance. Friction can be mathematically modeled by using learned estimation data as a function of the displacement, velocity. acceleration, and jerk of the actuator. This model has the distinctive feature that friction compensation can be achieved with a generalization capability for different conditions. The proposed positioning control approach with disturbance modeling and compensation has been verified by experiments using a table drive system on a machine stand. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(2): 31–39, 2010; Published online in Wiley InterScience ( www. interscience.wiley.com ). DOI 10.1002/eej.20928 相似文献
106.
In this study we revisit Weiser’s (1991) [5] vision of seamlessly integrated computing. We focus on nomadic workers who rely extensively on mobile technologies to conduct work. Using Star and Ruhleder’s (1996) [10] properties of infrastructure, we discuss how nonroutine users of infrastructure face particular challenges. We conducted an ethnographic investigation of nomadic workers in a large distributed organization. We examined strategies that they use to assemble their mobile office, to seek resources, and to synchronize with others across time zones. We discuss how their strategies are challenged by their lack of local knowledge of infrastructure. Our results suggest that until the field of pervasive computing can attain Weiser’s vision, the very users of ubiquitous computing need infrastructure to be visible. We discuss the implications for a design to support nomadic work. 相似文献
107.
Walber Arantes da Silva Juliana Aparecida Aricetti Alice Eiko Murakami Jesuí Vergílio Visentainer Makoto Matsushita 《LWT》2009,42(2):660-73
This experiment was carried out with 58-week old laying quails (Coturnix coturnix japonica) assigned to four treatment groups with eight quails per replication in six repetitions in a completely randomized design. The treatments consisted of diets with different levels of flaxseed (0, 1.5, 3.0, and 5.0%). The amounts of cholesterol and total lipids and the fatty acid composition of quail egg yolk were determined in four 21-day cycles. No difference was found in cholesterol levels between the four treatments and the four cycles. The increased ingestion of linolenic acid (LNA) in diet reduced the formation of arachidonic acid (AA) significantly. The 3.0 and 5.0% treatment groups presented a reduction in total saturated fatty acids (TSFA) with the increase in percent flaxseed in feed comparatively to the control value. The n-3 fatty acid level was high in all treatments when compared to that of the control group. The n-6/n-3 ratio decreased from 21.30 (control) to 4.52 (5.0%), which is a better value from the nutritional viewpoint. 相似文献
108.
Takahiro Funami Sakie Noda Makoto Nakauma Sayaka Ishihara Rheo Takahashi Saphwan Al-Assaf Shinya Ikeda Katsuyoshi Nishinari Glyn O. Phillips 《Food Hydrocolloids》2009,23(2):548-554
Aqueous solutions of gellan gum with comparable molecular mass but with different acyl contents were investigated by atomic force microscopy and rheological measurements in the presence of sodium chloride (NaCl). Results obtained were discussed in relation to our previous report using potassium chloride (KCl) as an added salt. For a low-acyl sample, continuous fibrous network structures were identified microscopically as in the case of KCl. The network structures were more heterogeneous than those formed with KCl in terms of the height distribution of molecular assemblies. Rheological thermal hysteresis between sol–gel transitions was detected as in the case of KCl. The storage modulus (G′) of the gelled system was ca. 15% of the corresponding data with KCl at 20 °C. For a high-acyl sample, no continuous network structures were identified but branches with observable ends were identified as in the case of KCl. The hysteresis was less evident than the corresponding data with KCl and for the low-acyl sample with NaCl. Also, G′ values at 20 °C were ca. 30% and 20% of the corresponding data with KCl and for the low-acyl sample with NaCl, respectively. Continuousness and homogeneity of network structures related to the hysteresis and elasticity of the system, respectively. 相似文献
109.
Hideharu Mori Yosuke Saito Eri Takahashi Kazuhiro Nakabayashi Atsuhiko Onuma Makoto Morishima 《Reactive and Functional Polymers》2013,73(4):658-667
Novel organic–inorganic hybrids with sulfonic acid groups were prepared using random copolymers composed of vinyl sulfonate esters and vinyl trialkoxysilanes. Five vinyl sulfonate esters with different substituent groups were employed as protecting monomers for the production of the poly(vinyl sulfonic acid) component, and three vinyl trialkoxysilanes were used as cross-linkable monomers. Free radical and reversible addition-fragmentation chain transfer (RAFT) copolymerizations were performed for the production of random copolymers with two different functional groups. The selective deprotection of the sulfonate esters of the copolymers proceeded smoothly and resulted in the formation of copolymers with lithium vinyl sulfonate units and cross-linkable trialkoxysilane units. The co-condensation of the trialkoxysilane moieties in the deprotected copolymers with cross-linkers yielded transparent hybrid films that contained lithium sulfonate groups without aromatic rings or ester linkages. 相似文献
110.