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131.
Tanaka Takanori; Miwa Naofumi; Kawamura Satoru; Sohma Hitoshi; Nitta Katsutoshi; Matsushima Norio 《Protein engineering, design & selection : PEDS》1999,12(5):395-405
P26olf from olfactory tissue of frog, which may be involvedin olfactory transduction or adaptation, is a Ca2+-binding proteinwith 217 amino acids. The p26olf molecule contains two homologousparts consisting of the N-terminal half with amino acids 1109and the C-terminal half with amino acids 110217. Eachhalf resembles S100 protein with about 100 amino acids and containstwo helixloophelix Ca2+-binding structural motifsknown as EF-hands: a normal EF-hand at the C-terminus and apseudo EF-hand at the N-terminus. Multiple alignment of thetwo S100-like domains of p26olf with 18 S100 proteins indicatedthat the C-terminal putative EF-hand of each domain containsa four-residue insertion when compared with the typical EF-handmotifs in the S100 protein, while the N-terminal EF-hand ishomologous to its pseudo EF-hand. We constructed a three-dimensionalmodel of the p26olf molecule based on results of the multiplealignment and NMR structures of dimeric S100B(ßß)in the Ca2+-free state. The predicted structure of the p26olfsingle polypeptide chain satisfactorily adopts a folding patternremarkably similar to dimeric S100B(ßß). Each domainof p26olf consists of a unicornate-type four-helix bundle andthey interact with each other in an antiparallel manner formingan X-type four-helix bundle between the two domains. The twoS100-like domains of p26olf are linked by a loop with no sterichindrance, suggesting that this loop might play an importantrole in the function of p26olf. The circular dichroism spectraldata support the predicted structure of p26olf and indicatethat Ca2+-dependent conformational changes occur. Since theC-terminal putative EF-hand of each domain fully keeps the helixloophelixmotif having a longer Ca2+-binding loop, regardless of the four-residueinsertion, we propose that it is a new, novel EF-hand, althoughit is unclear whether this EF-hand binds Ca2+. P26olf is a newmember of the S100 protein family. 相似文献
132.
Masatake Kawada Zen‐Ichiro Kawasaki Kenji Matsu‐ura Toshio Musashiya Satoru Kuroki Teruya Osawa Hiroki Tanaka 《Electrical Engineering in Japan》2000,132(1):38-45
Partial discharge (PD) within voids in a solid insulating system is a symptom and/or a direct cause of deterioration of a generator winding. It is reported that PD is a very short duration current and/or voltage pulse, about 1 to 5 ns. Generally PD emits an electromagnetic wave which is a broadband range signal (≈ gigahertz). Therefore, we developed a new system for detecting the electromagnetic wave, especially microwaves (gigahertz) associated with a material defect of the winding. From the point of view of preventing accidents of insulation breakdown, it is important to assess the condition of the winding. We applied our system to a dielectric breakdown test to learn the relation between the characteristics of the microwaves and the insulation condition of the winding. The dielectric breakdown test is believed to be useful for estimating the minimum breakdown voltage which is a criterion of the insulation condition of the winding. Experimental results showed that this system was able to assess the insulation condition by measuring the number of pulses and the amplitude of the microwaves per voltage cycle. © 2000 Scripta Technica, Electr Eng Jpn, 132(1): 38–45, 2000 相似文献
133.
Correlation equations for saturated and subcooled film boiling heat transfer from a downward-facing horizontal circular plate are proposed based on a theoretical study using an integral method. For the case of subcooled liquids, a dimensionless heat transfer parameter is introduced to effectively correlate within ±15% the experimental data obtained under both quenching and steady-state conditions. © 1998 Scripta Technica, Heat Trans Jpn Res, 26(7): 459–468, 1997 相似文献
134.
This article reports the effect of cell structure on oil absorption of highly oil-absorptive polyurethane foam (ON-PUR), which is suitable for on-site foaming. We have developed ON-PUR as an oil absorbing polyurethane foam using a very reactive recipe. ON-PUR was synthesized by mixing polyol, water, additives, and polymeric diphenylmethane diisocyanate (P-MDI) using a high-pressure foaming machine. Density, airflow, oil absorption of this foam, and cell structure by microscopy were measured. From these results, it was found that the airflow of this foam increased by crushing, and the oil absorption of this foam increased sharply in a narrow airflow range (from 0.1 to 0.8 scfm). This increase is estimated to be due to the decrease of closed cell structures by crushing treatment. Furthermore, we constituted on-site foaming system in bench scale, which was expected to be applicable to on-site preparation of ON-PUR. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65: 179–186, 1997 相似文献
135.
Multifaceted Analysis of IL-23A- and/or EBI3-Including Cytokines Produced by Psoriatic Keratinocytes
Kota Tachibana Nina Tang Hitoshi Urakami Ai Kajita Mina Kobashi Hayato Nomura Minori Sasakura Satoru Sugihara Fan Jiang Nahoko Tomonobu Masakiyo Sakaguchi Mamoru Ouchida Shin Morizane 《International journal of molecular sciences》2021,22(23)
Interleukin (IL) 23 (p19/p40) plays a critical role in the pathogenesis of psoriasis and is upregulated in psoriasis skin lesions. In clinical practice, anti-IL-23Ap19 antibodies are highly effective against psoriasis. IL-39 (p19/ Epstein-Barr virus-induced (EBI) 3), a newly discovered cytokine in 2015, shares the p19 subunit with IL-23. Anti-IL-23Ap19 antibodies may bind to IL-39; also, the cytokine may contribute to the pathogenesis of psoriasis. To investigate IL23Ap19- and/or EBI3-including cytokines in psoriatic keratinocytes, we analyzed IL-23Ap19 and EBI3 expressions in psoriasis skin lesions, using immunohistochemistry and normal human epidermal keratinocytes (NHEKs) stimulated with inflammatory cytokines, using quantitative real-time polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), and liquid chromatography-electrospray tandem mass spectrometry (LC-Ms/Ms). Immunohistochemical analysis showed that IL-23Ap19 and EBI3 expressions were upregulated in the psoriasis skin lesions. In vitro, these expressions were synergistically induced by the triple combination of tumor necrosis factor (TNF)-α, IL-17A, and interferon (IFN)-γ, and suppressed by dexamethasone, vitamin D3, and acitretin. In ELISA and LC-Ms/Ms analyses, keratinocyte-derived IL-23Ap19 and EBI3, but not heterodimeric forms, were detected with humanized anti-IL-23Ap19 monoclonal antibodies, tildrakizumab, and anti-EBI3 antibodies, respectively. Psoriatic keratinocytes may express IL-23Ap19 and EBI3 proteins in a monomer or homopolymer, such as homodimer or homotrimer. 相似文献
136.
Hatakeyama E Kajita H Sugawara T Sasaki A Takahashi S Komukai T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2006,47(4):137-145
A method for simultaneous determination of multiple pesticide residues in agricultural products was developed by using a pretreatment with ultrafiltration, followed by liquid chromatography-tandem mass spectrometry (LC/MS/MS). The pretreatment process (extraction of pesticides from agricultural products with methanol, dilution of the extract with water, and ultrafiltration) gave recoveries in the range of 50-150% for 63 of 83 pesticides spiked at 0.25 microg/ g into 6 agricultural products. The detection limits of pesticides by LC/MS/MS were below 0.0005-0.05 micro/g. This method is useful for screening purposes and for multiresidue analysis of pesticides in agricultural products. Pesticide residues in 50 domestic crops were investigated by this method, and residues of 14 pesticides were detected in 30 crops. 相似文献
137.
A dynamic electronic speckle pattern interferometry method is applied to investigate thermal expansion of a joint material (ceramic-stainless steel) as a practical industrial object. The speckle interference signal is considered in the temporal domain and the phase is analyzed by the Hilbert transform method. Errors caused by the bias and modulation variations over the phase values are first examined by numerical simulation. Two experiments are performed with in-plane and out-of-plane sensitive systems to study the 3D deformation field thoroughly. The deformation field showed clearly the difference between the thermal expansions of the stainless steel and ceramic. It was also revealed that the boundary of materials and its vicinity suffer very large thermal strain due to the significantly large difference in the linear coefficient of thermal expansions. 相似文献
138.
An experiment to investigate the potential of a laser-induced plasma method for determining concrete compressive strength was conducted by focusing a Nd:YAG laser on concrete samples with different degrees of compressive strength. This technique was developed in light of the role of the shock wave in the generation of a laser-induced plasma. It was found that the speed of the shock front depends on the hardness of the sample. It was also found that a positive relationship exists between the speed of the shock front and the ionization rate of the ablated atoms. Hence, the ratio of the intensity between the Ca(II) 396.8 nm and Ca(I) 422.6 nm emission lines detected from the laser-induced plasma can be used to examine the hardness of the material. In fact, it was observed that the ratio changes with respect to the change in the concrete compressive strength. The findings also show that the ratio increases with time after the cement is mixed with water. 相似文献
139.
Ultramultiple roundtrips of surface acoustic wave on sphere realizing innovation of gas sensors 总被引:1,自引:0,他引:1
Yamanaka K Ishikawa S Nakaso N Takeda N Sim DY Mihara T Mizukami A Satoh I Akao S Tsukahara Y 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2006,53(4):793-801
A thin beam of wave usually diverges due to diffraction, which is a limitation of any device using such waves. However, a surface acoustic wave (SAW) on a sphere with an appropriate aperture does not diverge but is naturally collimated, realizing ultramultiple roundtrips along an equator of the sphere. This effect is caused by the balance between diffraction and focusing on a spherical surface, and it enables realization of high-performance ball SAW sensors. The advantage of ball SAW is most fully appreciated when applied to a very thin sensitive film for which the multiple-roundtrip enhances the sensitivity, but the attenuation loss is not very large. It is exemplified in a hydrogen gas sensor that realizes a wide sensing range of 10 ppm to 100% for the first time, and realizes relatively fast response time of 20 s without heating the sensitive film. 相似文献
140.
Index characterization of differential–algebraic equations in hybrid analysis for circuit simulation
Mizuyo Takamatsu Satoru Iwata 《International Journal of Circuit Theory and Applications》2010,38(4):419-440
Modern modeling approaches in circuit simulation naturally lead to differential–algebraic equations (DAEs). The index of a DAE is a measure of the degree of numerical difficulty. In general, the higher the index, the more difficult it is to solve the DAE. The modified nodal analysis (MNA) is known to yield a DAE with index at most two in a wide class of nonlinear time‐varying electric circuits. In this paper, we consider a broader class of analysis method called the hybrid analysis. For linear time‐invariant RLC circuits, we prove that the index of the DAE arising from the hybrid analysis is at most one, and give a structural characterization for the index of a DAE in the hybrid analysis. This yields an efficient algorithm for finding an optimal hybrid analysis in which the index of the DAE to be solved attains zero. Finally, for linear time‐invariant electric circuits that may contain dependent sources, we prove that the optimal hybrid analysis by no means results in a higher index DAE than MNA. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献