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81.
Tomoki Okata Kiyotaka Asanuma Kenichiro Nakagawa Waku Hatta Tomoyuki Koike Akira Imatani Atsushi Masamune 《International journal of molecular sciences》2022,23(22)
An unidentified cause of functional dyspepsia (FD) is closely associated with medication resistance. Acid suppression is a traditional and preferential method for the treatment of FD, but the efficacy of this treatment varies between epigastric pain syndrome (EPS) and postprandial syndrome (PDS): it is efficient in the former but not much in the latter. Transepithelial electrical resistance (TEER), a surrogate of mucosal barrier function, was measured under pH 3 and pH 5 acidic conditions using duodenal biopsy specimens obtained from the patients with EPS and PDS and asymptomatic healthy controls. The infiltration of inflammatory cells to the duodenal mucosa was accessed by immunohistochemical analysis. The duodenal mucosal TEER in EPS patients was decreased by exposure to the acidic solution compared to that of the controls and the PDS patients. The decrease in TEER of the EPS patients was observed even under pH 5 weak acidic condition and was correlated to degree of the epigastric pain. Moreover, the duodenal mucosa of EPS patients presented an increase in mast cells and plasma cells that expressed Ig-E. Duodenal mucosal vulnerability to acid is likely to develop EPS. 相似文献
82.
S Kurotobi H Naito T Sano J Arisawa T Matsushita M Takeuchi S Kogaki S Okada 《Canadian Metallurgical Quarterly》1998,67(1):55-63
The highly reactive and cytotoxic hydroxyl radical (OH) was found by electrochemical detection to be produced in reactions involving hydrogen peroxide (H2O2) and the nitric oxide (NO) donor diethylamine- NO complex. Using aromatic hydroxylation of salicylate as a specific indicator of OH, three salicylate hydroxylation products were identified; catechol, 2,3- and 2,5-dihydroxybenzoic acid. Four additional compounds were detected but not identified. The interactions of H2O2 and NO represent a biologically feasible reaction mechanism that can account for OH-induced damage in cellular environments where transition metal ions are unavailable for participation in the superoxide-mediated Fenton reaction. The ability of the NO/H2O2 complex to generate OH independently of iron or other transition metals provides a new focus for studies concerned with the origin of tissue-specific damage caused by oxygen-derived species. 相似文献
83.
The spectral emission of a ceramic plate coated with a rare‐earth oxide thin film was investigated for thermophotovoltaic (TPV) applications using a one‐dimensional radiative transfer analysis. The selective emitter has emission bands at wavelengths around 1 and 1.5 μm due to erbium. In the temperature range between 1400 and 1500 K, the radiant energy within these bands is remarkably large, because the Planck distribution has a peak at a wavelength of approximately 2 μm. In addition, the spectral response of a GaSb TPV cell has a peak at around 1.5 μm; therefore, the radiant energy of the emission bands is quite useful for the TPV generation of electricity. The total spectral efficiency for both the 1 μm and 1.5 μm bands reaches a maximum value of 0.295 for a film thickness between 0.2 and 0.3 mm. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20286 相似文献
84.
Skylight for Interior Lighting Design 总被引:2,自引:0,他引:2
Yoshinori Dobashi Kazufumi Kaneda Takanobu Nakashima Hideo Yamashita Tomoyuki Nishita Kastumi Tadamura 《Computer Graphics Forum》1994,13(3):85-96
It is inevitable for indoor lighting design to render a room lit by natural light, especially for an atelier or an indoor pool where there are many windows. This paper proposes a method for calculating the illuminance due to natural light, i.e. direct sunlight and skylight, passing through transparent planes such as window glass. The proposed method makes it possible to efficiently calculate such illuminance accurately, because it takes into account both non-uniform luminous intensity distribution of skylight and the distribution of transparency of glass according to incident angles of light. Several examples including the lighting design in an indoor pool, are shown to demonstrate the usefulness of the proposed method. 相似文献
85.
Mizuki Tenjimbayashi Sadaki Samitsu Yuko Watanabe Yasuyuki Nakamura Masanobu Naito 《Advanced functional materials》2021,31(21):2010957
Liquid marble (LM) is a droplet that is wrapped by hydrophobic solid particles, which behave as a non-wetting soft solid. Based on these properties, LM can be applied in fluidics and soft device applications. A wide variety of functional particles have been synthesized to form functional LMs. However, the formation of multifunctional LMs by integrating several types of functional particles is challenging. Here, a general strategy for the flexible patterning of functional particles on droplet surfaces in a patchwork-like design is reported. It is shown that LMs can switch their macroscopic behavior between a stable and active state on super-repellent surfaces in situ by jamming/unjamming the surface particles. Active LMs hydrostatically coalesce to form a self-sorted particle pattern on the droplet surface. With the support of LM handling robotics, on-demand cyclic activation–manipulation–coalescence–stabilization protocols by LMs with different sizes and particle types result in the reliable design of multi-faced LMs. Based on this concept, a single bi-functional LM is designed from two mono-functional LMs as an advanced droplet carrier. 相似文献
86.
Araki Wakiuchi Shogo Takasuka Shigehito Asano Ryo Hashizume Aniruddha Nag Miho Hatanaka Tomoyuki Miyao Yuya Ohnishi Takamitsu Matsubara Tsuyoshi Ando Tetsunori Sugawara Mikiya Fujii Hiroharu Ajiro 《大分子材料与工程》2023,308(6):2200626
It is important to match the feeding ratio of comonomers to the composition ratio in the resulting copolymers as closely as possible in industrial production, where the goal is often to produce more a homogeneous composition in copolymers. In this study, a flow copolymerization system with a conventionally initiated free radical method, together with randomly selected polymerization conditions is investigated. It is succeeded in achieving a closer match between the composition ratio and feeding ratio than previously reported in the copolymerization of styrene with methyl methacrylate and of glycidyl methacrylate with methyl methacrylate, which will widen the range of applications, by precisely controlling the mixing and heating in a flow polymerization apparatus. This is confirmed by the fact that the estimated values of reactivity ratios, r1 and r2, which are used in the reaction kinetics of copolymerization, are close to 1. 相似文献
87.
Yonghao Yue Kei Iwasaki Bing‐Yu Chen Yoshinori Dobashi Tomoyuki Nishita 《Computer Graphics Forum》2011,30(7):1911-1919
Photo‐realistic rendering of inhomogeneous participating media with light scattering in consideration is important in computer graphics, and is typically computed using Monte Carlo based methods. The key technique in such methods is the free path sampling, which is used for determining the distance (free path) between successive scattering events. Recently, it has been shown that efficient and unbiased free path sampling methods can be constructed based on Woodcock tracking. The key concept for improving the efficiency is to utilize space partitioning (e.g., kd‐tree or uniform grid), and a better space partitioning scheme is important for better sampling efficiency. Thus, an estimation framework for investigating the gain in sampling efficiency is important for determining how to partition the space. However, currently, there is no estimation framework that works in 3D space. In this paper, we propose a new estimation framework to overcome this problem. Using our framework, we can analytically estimate the sampling efficiency for any typical partitioned space. Conversely, we can also use this estimation framework for determining the optimal space partitioning. As an application, we show that new space partitioning schemes can be constructed using our estimation framework. Moreover, we show that the differences in the performances using different schemes can be predicted fairly well using our estimation framework. 相似文献
88.
Jun-ichiro Furukawa Tomoyuki Noda Tatsuya Teramae Jun Morimoto 《Advanced Robotics》2015,29(7):505-514
This paper proposes a fault tolerant framework for biosignal-based robot control with multiple sensor electrodes. In this approach, to cope with sensor faults, a reliable joint torque estimation model is selected from a group of estimation models based on sensor failure classifiers. The correlation among the electromyography (EMG) signal streams is used as input feature vectors for fault detection. To validate our proposed method, we artificially disconnect an EMG electrode or detach one side of an EMG probe from the skin surface during elbow-joint torque estimation experiments with five participants. When one EMG sensor electrode experiences one of the problems, the experimental results show that the joint torque can be estimated with significantly fewer errors using our proposed approach than a joint torque estimation method without sensor fault detection or than a method with a conventional sensor fault detection algorithm. Furthermore, we controlled a mannequin-arm-attached one-DOF exoskeleton based on the estimated torque profiles by generating movements with the estimated torque derived from the selected model. 相似文献
89.
Phase relations in the composition range from to were studied by electrical-conductivity measurements and X-ray diffraction in the ranges and . The plot of log σ versus log showed straight lines with distinct slopes, which corresponded to four regions (, , and ). The existence of the hyperstoichiometric phase was suggested in the temperature range from 1025 to 1126°C. The peritectoid temperature () was estimated to be present between 1126 and 1131°C. The partial free enthalpies and entropies for the two-phase equilibrium (, and ) were calculated and compared with previous results. From the dependence of the electrical conductivity on the oxygen partial pressure the nonstoichiometric defect structures of and were interpreted as consisting of doubly charged oxygen interstitials (Oi'') and doubly charged oxygen vacancies (VO''). At room temperature, the homogeneity range of the U4O9 phase was investigated with a Debye-Scherrer camera. 相似文献
90.
JosA. Castillo Christine Gurard‐Hlaine Mariana Gutirrez Xavier Garrabou Martine Sancelme Melanie Schürmann Tomoyuki Inoue Virgil Hlaine Franck Charmantray Thierry Gefflaut Laurence Hecquet Jesús Joglar Pere Claps GeorgA. Sprenger Marielle Lemaire 《Advanced Synthesis \u0026amp; Catalysis》2010,352(6):1039-1046
A mutant of D ‐fructose‐6‐phosphate aldolase (FSA) of Escherichia coli, FSA A129S, with improved catalytic efficiency towards dihydroxyacetone (DHA), the donor substrate in aldol addition reactions, was explored for synthetic applications. The kcat/KM value for DHA was 17‐fold higher with FSA A129S than that with FSA wild type (FSA wt). On the other hand, for hydroxyacetone as donor substrate FSA A129S was found to be 3.5‐fold less efficient than FSA wt. Furthermore, FSA A129S also accepted glycolaldehyde (GA) as donor substrate with 3.3‐fold lower affinity than FSA wt. This differential selectivity of both FSA wt and FSA A129S for GA makes them complementary biocatalysts allowing a control over donor and acceptor roles, which is particularly useful in carboligation multi‐step cascade synthesis of polyhydroxylated complex compounds. Production of the mutant protein was also improved for its convenient use in synthesis. Several carbohydrates and nitrocyclitols were efficiently prepared, demonstrating the versatile potential of FSA A129S as biocatalyst in organic synthesis. 相似文献