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101.
Sweet potato starch (SPS) with 20 or 25% moisture was heated and then fused at 150°C for 15 min under pressurization at 30–500 Kg/cm2. At the same time, the heated SPS melt was extruded through a capillary tube under specified pressure in order to give shearing force. Thus, intact SPS, heated SPS and heated sheared SPS specimen were prepared and examined. The heated and heated sheared SPS did not contain any pyrolysis products because their spectrum profiles were the same as that of intact SPS. By heating and shearing, the intact SPS molecule was depolymerized into small molecules including a few amount of glucose. This finding was revealed by means of molecular weight estimation by viscometry and by gel filtration. The shearing toward SPS melt markedly stimulated the depolymerization while the effect of only heating on depolymerization of SPS was modulate in comparison with heated shearing. Water solubilities of intact SPS, heated SPS and heated sheared SPS with 20% moisture were 0.07, 3.5 and 51.5% respectively, and also the degrees of gelatinization of 1.8% for intact starch increased markedly to 29% for heated SPS and 80–95% (depending on the pressure at extrusion) for heated sheared SPS. 相似文献
102.
Shinji Miwa Norio Yamamoto Katsuhiro Hayashi Akihiko Takeuchi Kentaro Igarashi Hiroyuki Tsuchiya 《International journal of molecular sciences》2022,23(3)
Simple SummaryChondrosarcomas develop chemoresistance to standard anticancer drugs, making it difficult to control unresectable or metastatic chondrosarcomas. To improve the clinical outcomes of chondrosarcoma, new treatment approaches, such as molecule-targeting agents and immunotherapy, are needed. Recent research has revealed promising biomarkers and therapeutic targets for chondrosarcoma. In addition, several molecule-targeting agents have shown favorable antitumor activities in several clinical studies in patients with advanced sarcomas, including chondrosarcoma. This review summarizes recent basic studies on biomarkers and therapeutic targets and recent clinical studies on treating chondrosarcomas.AbstractDue to resistance to standard anticancer agents, it is difficult to control the disease progression in patients with metastatic or unresectable chondrosarcoma. Novel therapeutic approaches, such as molecule-targeting drugs and immunotherapy, are required to improve clinical outcomes in patients with advanced chondrosarcoma. Recent studies have suggested several promising biomarkers and therapeutic targets for chondrosarcoma, including IDH1/2 and COL2A1. Several molecule-targeting agents and immunotherapies have shown favorable antitumor activity in clinical studies in patients with advanced chondrosarcomas. This review summarizes recent basic studies on biomarkers and molecular targets and recent clinical studies on the treatment of chondrosarcomas. 相似文献
103.
Yuki Tanaka Takumi Sako Tatsuhiro Hiraoka Misaki Yamaguchi Masayuki Yamaguchi 《应用聚合物科学杂志》2020,137(46):49516
The structure and rheological properties of binary blends of polycarbonate (PC) and polystyrene (PS) were investigated using various PS samples with different molecular weights, namely PS1k (Mw = 1,000), PS53k (Mw = 53,000), and PS240k (Mw = 240,000). The blends with PS53k and PS240k show phase-separated structures, whereas the blend with PS1k is miscible. The shear viscosity decreases greatly on addition of PS53k and PS240k, especially at high shear rates, which would be a great advantage at processing operations. Because the nonlinear response occurs in the small strain region for multilayered films of PC and PS240k, the origin of the significant viscosity drop for the phase-separated system is interfacial slippage at the phase boundary. 相似文献
104.
The influence of feed supply time on the fatty acid profile of Nile tilapia (Oreochromis niloticus) fed on a diet enriched with n-3 fatty acids 总被引:2,自引:0,他引:2
K. C. Justi C. Hayashi J. V. Visentainer N. E. de Souza M. Matsushita 《Food chemistry》2003,80(4):489-493
The purpose of the study was to examine the fatty acid profiles of Nile tilapia (Oreochromis niloticus) submitted to different feeding times (0, 10, 20 and 30 days) on a diet enriched with n-3 fatty acids, by addition of flaxseed oil in substitution for sunflower oil. The main fatty acids detected were palmitic (C16:0), stearic (C18:0), oleic (C18:1n9), linoleic (C18:2n6) and -linolenic (C18:3n3) in all the treatments. The 30 day-fed fish presented the best values for total n-3 fatty acids, with a prominence of -linolenic acids, showing that the flaxseed oil as well as the feed supply time influenced the fatty acid profiles. 相似文献
105.
Kazuaki Shibuki Taku M. Aida Hiromichi Hayashi 《The Journal of Supercritical Fluids》2010,54(2):266-271
Sub-micron sized Zn2SiO4:Mn2+ phosphors particles were continuously synthesized in supercritical water with a flow reactor. Colloidal silica or sodium silicate was used as the Si source. Zn and Mn sources were chosen from their nitrates, sulfates, and acetates. The syntheses were carried out at temperatures from 400 to 500 °C, at pressures from 30 to 35 MPa, at NaOH concentrations from 0.014 to 0.025 M, and for residence times from 0.025 to 0.18 s. Sodium silicate formed α- and β-Zn2SiO4:Mn2+ phases regardless of the Zn and Mn sources, while colloidal silica formed phases dependent on the type of Zn and Mn sources used in addition to the use of alkali. As the reaction temperature increased, the crystallinity of α-Zn2SiO4:Mn2+ phase increased and the Mn substitution into the Zn sites of the α-Zn2SiO4 phase decreased. Of the conditions studied, the most highly crystalline α-Zn2SiO4:Mn2+ was produced at a temperature of 400 °C, a pressure of 30 MPa, a NaOH concentration of 0.14 M, and a residence time of 0.13 s with Zn and Mn sulfates and colloidal silica as starting materials. The α-Zn2SiO4:Mn2+ fine particles synthesized were round in shape, had an average diameter of 268 nm, and exhibited a green-emission with a peak wavelength of 524 nm. 相似文献
106.
Shin-ichi Hirano Takashi Hayashi Masashi Miura 《Journal of the American Ceramic Society》1990,73(4):885-888
Superconducting Ba2 YCu3 O7-δ thin films were prepared through an organometallic route. Single-phase Ba2 YCu3 O7-δ thin films with preferred orientation were successfully prepared on SrTiO3 (100) single-crystal substrates at 800°C by a dip coating method using partially hydrolyzed Ba-Y-Cu organometallic solutions. Preferentially oriented Ba2 YCu3 -O7-δ thin films were also prepared on MgO (100) substrates. By controlling the partial hydrolysis conditions, a coating solution for precursor thin films was kept accurately at the stoichiometric composition. The use of ozone gas during the pyrolysis of the precursor thin films was found to suppress the formation of BaCO3 . Ba2 YCu3 O7-δ thin films with c -axis orientation perpendicular to a SrTiO3 (100) substrate, which were heat-treated at 900°C for 15 min, exhibited a superconductivity transition with an onset of 90 K and an end of 75 K. 相似文献
107.
Masaki Honda Hakuto Kageyama Takashi Hibino Rungaroon Waditee‐Sirisattha Tetsuya Fukaya Yoshiaki Hayashi Motonobu Goto 《European Journal of Lipid Science and Technology》2020,122(3)
Z‐isomers of lycopene exhibit higher bioavailability and antioxidant capacity than those of the all‐E‐isomer. Therefore, it is important to develop an efficient and environmentally friendly procedure for Z‐isomerization. The current methods for Z‐isomerization of (all‐E)‐lycopene use toxic chemicals such as organic solvents and catalysts. This study is aimed to develop a chemical‐free method for Z‐isomerization of (all‐E)‐lycopene in tomato powder by hot air and superheated steam heating. The Z‐isomerization reaction is promoted by heating above the melting point of lycopene. When heated with superheated steam, the thermal decomposition of lycopene is suppressed compared to that when heated with hot air. When tomato powder is heated at 240 °C for 5 min by superheated steam, the total Z‐isomer content and remaining lycopene are 69.0% and 90.7%, respectively, while with hot air heating, the total Z‐isomer content and remaining lycopene are 69.9% and 68.0%, respectively. These results indicate that the thermal Z‐isomerization of lycopene occurs in the molten state and heating in a low oxygen atmosphere suppresses the thermal decomposition of lycopene. Practical Applications: Tomato powder rich in lycopene Z‐isomers is an important ingredient for the food and animal feed industries. Since Z‐isomers of lycopene are more soluble in solvents including ethanol which is a low‐toxicity and environmentally friendly solvent, the efficiency of lycopene extraction with ethanol can be improved by using the Z‐isomer‐rich tomato powder as a raw material. The obtained Z‐isomer‐rich extract has a high added value because the Z‐isomers have higher bioavailability and antioxidant capacity than those of the all‐E‐isomer. In addition, since lycopene Z‐isomers exhibit higher accumulation efficiency and better color improvement in hen egg yolks than those of the all‐E‐isomer, Z‐isomer‐rich tomato powder is an effective animal feed. 相似文献
108.
Yoshitoshi Saito Shigeo Hayashi Atsuo Yasumori Kiyoshi Okada 《Journal of Porous Materials》1996,3(4):233-239
This paper describes the effects of calcining conditions of kaolinite on pore structures of the porous materials obtained from the selective leaching of calcined kaolinite using KOH solution. Mesoporous -Al2O3 was the predominant crystalline phase in the samples calcined in the temperature range between 950°C and 1050°C for 24 h. The mean specific surface area of these samples was approximately 250 m2 · g–1 and the mean total pore volume was approximately 0.8 ml · g–1. The pore size distribution curves of these samples showed a sharp peak at around 2–3 nm pore radius. This peak was sharper for the sample calcined at 1000°C for 24 h. On the other hand, the pore sizes of the sample calcined at 1100°C for 24 h increased abruptly to 10–20 nm and this change corresponded to the formation of mullite in the sample. The pore sizes of the samples calcined at 1100°C varied with calcining time. The specific surface area and total pore volume decreased, the longer the calcining time of the samples, and this was correlated with an increase in the amount of mullite in the samples. 相似文献
109.
Inside Cover: Molecular Design of an Environmentally Sensitive Fluorescent Nucleoside, 3‐Deaza‐2′‐Deoxyadenosine Derivative: Distinguishing Thymine by Probing the DNA Minor Groove (ChemBioChem 11/2014)
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110.
The importance of transparent conductive film is increasing due to its use in applications such as touch‐panel devices. Although indium tin oxide is widely used because of its high conductivity and transparency, conductive polymers are being studied as alternative materials that avoid the use of rare metals and the brittleness associated with existing systems. Polyethylene dioxythiophene (PEDOT)/polyethylene sulfonic acid (PSS) is drawing a lot of attention due to its well‐balanced conductivity, transparency, film formability, and chemical stability. The nonconductive PSS reportedly covers the conductive PEDOT. The PSS shell provides carrier and film‐formability to PEDOT but is also a barrier that hinders electrical conductivity. Therefore, the PEDOT film formability is explored supported by a substrate without the addition of PSS. The “hierarchical nanoporous layer glass” holds the PSS‐free PEDOT with its nanopores to form a homogeneous, transparent film. The PSS‐free PEDOT film thus achieves transparency of over 85% and resistivity of below 500 Ω sq?1. 相似文献