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11.
Natsuko Goda Kana Shimizu Yohta Kuwahara Takeshi Tenno Tamotsu Noguchi Takahisa Ikegami Motonori Ota Hidekazu Hiroaki 《International journal of molecular sciences》2015,16(7):15743-15760
Intrinsically disordered proteins (IDPs) that lack stable conformations and are highly flexible have attracted the attention of biologists. Therefore, the development of a systematic method to identify polypeptide regions that are unstructured in solution is important. We have designed an “indirect/reflected” detection system for evaluating the physicochemical properties of IDPs using nuclear magnetic resonance (NMR). This approach employs a “chimeric membrane protein”-based method using the thermostable membrane protein PH0471. This protein contains two domains, a transmembrane helical region and a C-terminal OB (oligonucleotide/oligosaccharide binding)-fold domain (named NfeDC domain), connected by a flexible linker. NMR signals of the OB-fold domain of detergent-solubilized PH0471 are observed because of the flexibility of the linker region. In this study, the linker region was substituted with target IDPs. Fifty-three candidates were selected using the prediction tool POODLE and 35 expression vectors were constructed. Subsequently, we obtained 15N-labeled chimeric PH0471 proteins with 25 IDPs as linkers. The NMR spectra allowed us to classify IDPs into three categories: flexible, moderately flexible, and inflexible. The inflexible IDPs contain membrane-associating or aggregation-prone sequences. This is the first attempt to use an indirect/reflected NMR method to evaluate IDPs and can verify the predictions derived from our computational tools. 相似文献
12.
This study assesses the potential of ground reactive aggregates to reduce or suppress expansion associated with ASR. Particular attention is paid to fine admixtures (<80 μm) added to mortars, which contain the reactive aggregates from which the fines were ground. Many varieties of aggregate (quarried and natural, igneous, metamorphic and sedimentary rocks) from different geological settings were subjected to an autoclave test. The replacement of 10–20% of the sand by reactive aggregate powder (RAP) of different surface areas from 11 different reactive aggregates led to the reduction of ASR-expansion by up to 78% compared with control mortars. Increasing the amount of fines led to better performance. No clear relationship was observed between the reactivity degree of the aggregates and the efficiency of their ground powder to reduce expansion. A general trend was found regarding the fineness of ground aggregates: finer particles were more effective in reducing expansion. The reduction of the expansion due to RAP is discussed in terms of parameters affecting its efficiency and of the mechanisms responsible for the reduction. 相似文献
13.
Natsuko Sakai Tatsuo Tsunoda Natsuo Fukumoto Isao Kojima Katsuhiko Yamaji Teruhisa Horita Masahiko Ishikawa Harumi yokokawa masayuki Dokiya 《Journal of Electroceramics》1999,4(1):121-128
The morphological characteristics, chromium valence state, and cation transport in the vicinity of grain boundary in La1-xCaxCrO3 were investigated by using TEM/EDS, XPS and SIMS techniques. The width of grain boundary was around 1 nm where anomalous enrichment of calcium was observed. Higher valence state of chromium such as Cr6+(d0) was detected in the grain boundaries whereas Cr3+(d3) and Cr4+(d2) were dominant in the bulk. Very fast interdiffusion of alkaline earths was observed in the Sr2+-La0.75Ca0.25CrO3 system. All observed phenomena were correlated by assuming the A-site vacancy which may be induced by the formation of Cr6+ at grain boundaries. 相似文献
14.
N. Beaulieu T. D. Cyr E. G. Lovering 《Drug development and industrial pharmacy》1991,17(13):1843-1855
A high performance liquid chromatographic method has been developed for the assay of flurbiprofen, or flurbiprofen sodium and related compounds in drug raw materials and tablets. A phenyl column with a mobile phase of acetonitrile: 1.0% acetic acid (60:40) provide for the resolution of twenty-one related compounds from the drug. Minimum detectable levels of the related compounds are 0.01% and minimum quantifiable levels are 0.1% or less. Total impurity levels in seven raw materials ranged from 0.0 to 0.6%. One impurity, 2-(4-biphenylyl) propionic acid, is present in most samples at about 0.3%. A gas chromatographic method was developed for organic volatile impurities 相似文献
15.
Harumi Yokokawa Natsuko Sakai Tatsuya Kawada Masayuki Dokiy 《Journal of the American Ceramic Society》1990,73(3):649-658
The thermodynamic properties of double oxides in rare earth-transition metal (V and Mn)-oxygen ternary systems have been collected and evaluated to examine their stability using chemical potential diagrams plotted as log (αA /αB ) vs log ( P (O2 )). The thermodynamic regularities of perovskites, pyrochlores, and other compounds have been discussed in terms of the effective ionic radii across a series of rare earths. The obtained regularities have been used to estimate tentatively the thermodynamic properties of some rare-earth vanadium and manganese oxides. 相似文献
16.
Notes that test-item bias in the Wechsler Intelligence Scale for Children (WISC) and WISC—Revised (WISC—R) Information subtest has concerned Canadian psychologists for over 3 decades. Several investigators have attempted to identify and evaluate the source of this bias. The method of choice in these studies has been rank-order comparisons of pass-rates between the standardized and modified items. It is argued that this methodology is incomplete to establish the presence or absence of item bias. In addition to observing the rank order of pass rates, it is recommended that a chi-square approach be used based on the proportion of responses within ability levels to evaluate test item bias. The advantages of this strategy are demonstrated with WISC—R data from 342 12–16 yr old psychiatric inpatients and outpatients. Results demonstrate the power of this methodology over simple rank-order comparisons. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
17.
Kunikazu Ishii Natsuko FujitaHidemi Ogawa 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(9):1026-1028
We have developed a simple Rutherford backscattering spectroscopic (RBS) method to analyze sample depth profiles in air. To avoid excessive energy loss of projectile ions in air, we have used a 3 MeV proton beam extracted into air with a metal capillary. Using this capillary, we were able to extract a sufficiently large proton beam current to perform in-air RBS and in-air PIXE without requiring any window, such as a thin film, between a vacuum chamber and air. We have validated our technique by analyzing the depth profiles for Au foils of various thicknesses, 0.25, 0.75, and 2.5 μm. A comparison of the experimental results with a simple theoretical calculation indicates that this technique is useful for analyzing the depth profile of any specimen in air. 相似文献
18.
19.
Harumi Yokokawa Natsuko Sakai Teruhisa Horita Katsuhiko Yamaji Yueping Xiong Takanori Otake Hiroo Yugami Tatsuya Kawada Junichiro Mizusaki 《Journal of Phase Equilibria》2001,22(3):331-338
Phase diagram calculations that were made previously for the ZrO2-MO m/2 (m = 2, 3, 4) systems and for the ZrO2-YO1.5-MO m/2 (M = transition metals) systems have been extended to the ZrO2-YO1.5-CeO2(-CeO1.5) system to make an attempt to explain (1) thermogravimetric (TG) results as a function of oxygen potential, (2) electronic conductivity as a function of oxygen potential, and (3) a miscibility gap observed in air. The interaction parameters for the CeO2-CeO1.5-YO1.5 system were obtained from the reported oxygen nonstoichiometry in CeO2−x and rate earth doped ceria, (Ce,RE)O2−δ . The interaction parameters for the ZrO2-CeO2 subsystem were obtained so as to reproduce the observed miscibility gap at 1273 K. Those thermodynamic properties can reproduce consistently the experimental behaviors of the electronic conductivity and the TG results in the (Zr1−x Ce x )0.8Y0.2O1.9 solid solutions; these indicate the enhancement of reduction of CeO2. 相似文献
20.
The concentrations of traditional brominated flame retardants (BFRs) and organophosphate flame retardants (OPFRs) in new consumer products, including electronic equipment, curtains, wallpaper, and building materials, on the Japanese market in 2008 were investigated. Although some components of the electronic equipment contained bromine at concentrations on the order of percent by weight, as indicated by X-ray fluorescence analysis, the bromine content could not be fully accounted for by the BFRs analyzed in this study, which included polybrominated diphenylethers, decabromodiphenyl ethane, tetrabromobisphenol A, polybromophenols, and hexabromocyclododecanes. These results suggest the use of alternative BFRs such as newly developed formulations derived from tribromophenol, tetrabromobisphenol A, or both. Among the 11 OPFRs analyzed, triphenylphosphate was present at the highest concentrations in all the products investigated, which suggests the use of condensed-type OPFRs as alternative flame retardants, because they contain triphenylphosphate as an impurity. Tripropylphosphate was not detected in any samples; and trimethylphosphate, tributyl tris(2-butoxyethyl)phosphate, and tris(1,3-dichloro-2-propyl)phosphate were detected in only some components and at low concentrations. Note that all the consumer products evaluated in this study also contained traditional BFRs in amounts that were inadequate to impart flame retardancy, which implies the incorporation of recycled plastic materials containing BFRs that are of global concern. 相似文献