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91.
Kojima K Hiratsuka A Suzuki H Yano K Ikebukuro K Karube I 《Analytical chemistry》2003,75(5):1116-1122
An electrochemical protein chip was microfabricated. A thin-film three-electrode system, including an array of 36 platinum working electrodes, a set of thin-film Ag/AgCl electrodes, and platinum auxiliary electrodes, was integrated on a glass substrate. Capture antibodies were immobilized in a 4.5-nm-thick double layer of a hexamethyldisiloxane plasma-polymerized film. Because of their highly cross-linked network structure, the capture antibodies could be firmly immobilized. No nonspecific adsorption was observed during a series of procedures to detect target proteins, and electrochemical cross talk between neighboring sites was negligible. The sandwich immunoassay was conducted on a single chip using model proteins, alpha-1-fetoprotein and beta2-microglobulin. A distinct current increase following the oxidation of hydrogen peroxide produced by the enzymatic reaction of glucose oxidase was observed, which indicates that the capture proteins could actually bind the target proteins. Two kinds of protein were detected independently on multiple sites with respective capture antibodies. 相似文献
92.
A novel lipid analog with two long alkyl (C16) chains, an aspartate skeleton, a connecting alkyl (C8) chain, and 2-nitrophenol trigger group is synthesized by an efficient synthetic route, which can induce liposome fusion
at physiological pH. 相似文献
93.
Muneharu Kuwata Hayato Takeuchi Tomohiro Sasagawa Shinji Yagyu Hiroaki Sugiura 《Journal of the Society for Information Display》2007,15(10):829-836
Abstract— A new light‐collection optics has been developed that enhances the luminance of projection TV which use lamps as the light source. The conventional optical system consists of an elliptical reflector and a flat‐surface front glass, but these systems cannot sufficiently collect the beams coming from the light source, and they cause loss in the coupling with the light pipe. To solve this problem, we devised a new optical system through a structure of an aspherical reflector and an aspherical front glass. This new optical system concentrates the beams coming from the light source to a smaller point which improves the coupling efficiency. Thus, we have successfully increased the luminance of the projection TV by approximately 10%. This paper reports the design principles of the new optical system and the results of a prototype experiment. 相似文献
94.
This paper proposes an optimal impedance control method for a variable stiffness actuator (VSA), in which a variable stiffness mechanism and an actuator are aligned in series. First, we introduce a circuit expression of the robotic system and provide a unified framework to determine an optimal index of robots driven by VSAs, irrespective of the presence or absence of the environment. Next, we design a torque controller for a one-degree-of-freedom (DOF) robot and find the optimal condition of the stiffness in the VSA for a given task. Then, we design a stiffness control law for the VSA exploiting the intrinsic indivisible property between motion and passive impedance. This stiffness control law adaptively tunes the passive stiffness to minimize the energy consumption without defining any explicit desired impedance, which is usually required in impedance controllers. The stability of the closed loop system is proved using Lyapunov’s analysis. Simulations and experimental results validate the effectiveness of the proposed method and the robustness in response to parameter changes. 相似文献
95.
Hiroaki Nasu 《控制论与系统》2013,44(6):563-582
96.
Hiroaki Kitano 《Applied Artificial Intelligence》2013,27(2-3):117-125
RoboCup, Robot World Cup, is an international research initiative involving over 20 countries and researchers from various fields surrounding artificial intelligence and robotics. This introductory article describes research programs involved in RoboCup. The goal of RoboCup is to establish a scheme of long-range research, and a series of short-range research goals that essentially converges into the grand challenge as well as creating numerous spin-off technologies. The range of research areas spans from robot hardware design, software and multiagent programming, to natural language systems and education. This article describes how these efforts can be coordinated as an integrative research initiative. 相似文献
97.
Shuang Bai Tetsuya Matsumoto Yoshinori Takeuchi Hiroaki Kudo Noboru Ohnishi 《Machine Vision and Applications》2013,24(5):959-970
In image classification based on bag of visual words framework, image patches used for creating image representations affect the classification performance significantly. However, currently, patches are sampled mainly based on processing low-level image information or just extracted regularly or randomly. These methods are not effective, because patches extracted through these approaches are not necessarily discriminative for image categorization. In this paper, we propose to utilize both bottom-up information through processing low-level image information and top-down information through exploring statistical properties of training image grids to extract image patches. In the proposed work, an input image is divided into regular grids, each of which is evaluated based on its bottom-up information and/or top-down information. Subsequently, every grid is assigned a saliency value based on its evaluation result, so that a saliency map can be created for the image. Finally, patch sampling from the input image is performed on the basis of the obtained saliency map. Furthermore, we propose a method to fuse these two kinds of information. The proposed methods are evaluated on both object categories and scene categories. Experiment results demonstrate their effectiveness. 相似文献
98.
Kenji Fukuzawa Hiroaki Tsuji Satoshi Hamaoka Mitsuhiro Shikida Shintaro Itoh Hedong Zhang 《Microsystem Technologies》2013,19(9-10):1567-1572
It is important to understand friction force in micro/nano mechanical devices both at high sliding speed and with high lateral resolution. Dual-axis friction force microscopes that can provide high lateral resolution and accuracy have been proposed; however, the sliding speed is limited by the probe scan speed. While a micro mechanical probe (MMP) with an electrostatic actuator can overcome this problem, details of probe design have not been established yet. This paper presents the principle of the mechanical design for an MMP with high force sensitivity and sufficient drive force. The dimensions of the double cantilever beam control the spring constants, resonant frequencies, and drive force. The use of an actuated MMP enables accurate friction force microscopy at high sliding speeds, which is required for the design of micro/nano mechanical devices. 相似文献
99.
100.
Dr. Yoshiaki Yasutake Dr. Taiki Nishioka Dr. Noriko Imoto Prof. Tomohiro Tamura 《Chembiochem : a European journal of chemical biology》2013,14(17):2284-2291
Vitamin D3 hydroxylase (Vdh) from Pseudonocardia autotrophica is a cytochrome P450 monooxygenase that catalyzes the two‐step hydroxylation of vitamin D3 (VD3) to produce 25‐hydroxyvitamin D3 (25(OH)VD3) and 1α,25‐dihydroxyvitamin D3 (1α,25(OH)2VD3). These hydroxylated forms of VD3 are useful as pharmaceuticals for the treatment of conditions associated with VD3 deficiency and VD3 metabolic disorder. Herein, we describe the creation of a highly active T107A mutant of Vdh by engineering the putative ferredoxin‐binding site. Crystallographic and kinetic analyses indicate that the T107A mutation results in conformational change from an open to a closed state, thereby increasing the binding affinity with ferredoxin. We also report the efficient biocatalytic synthesis of 25(OH)VD3, a promising intermediate for the synthesis of various hydroxylated VD3 derivatives, by using nisin‐treated Rhodococcus erythropolis cells containing VdhT107A. The gene‐expression cassette encoding Bacillus megaterium glucose dehydrogenase‐IV was inserted into the R. erythropolis chromosome and expressed to avoid exhaustion of NADH in a cytoplasm during bioconversion. As a result, approximately 573 μg mL?1 25(OH)VD3 was successfully produced by a 2 h bioconversion. 相似文献