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31.
Yoshifumi Atsushi Wataru Fumihiro Junji Hiroaki 《Sensors and actuators. B, Chemical》2009,140(2):649-655
A novel method for exchanging solutions used in biochemical analyses and a device to carry out the exchange are proposed. An array of plugs formed using six injectors was transported in a microflow channel using a main pump located at one end of the main flow channel. The injectors and main pump were operated on the basis of the change in volume caused by the electrolysis of water. Bubbles were produced from working electrodes; these bubbles caused a diaphragm placed below the injectors to inflate and occlude the inlet of the solution reservoir. Increase in the number of bubbles caused the reservoir to inject the solution into the main flow channel in the form of a plug. Each plug was individually transported downstream to the sensing area by the main pump, which was operated in a similar manner to the injector. The device was used for the detection of a tumor marker, α-fetoprotein (AFP). Plugs of necessary solutions were individually transported to the sensing area with immobilized primary antibodies to allow antigen–antibody binding, cleaning, and detection. The fluorescence intensity from the antibodies showed clear dependence on the concentration of AFP. The immobilization of antibodies could also be carried out on-chip. 相似文献
32.
33.
Tominaga J Michizoe J Kamiya N Ichinose H Maruyama T Goto M 《Journal of Bioscience and Bioengineering》2004,98(1):14-19
Catalytic oxidation of biphenyl derivatives was investigated using laccase in a homogeneous aqueous-organic system. A thermostable laccase from Trametes sp. showed the highest catalytic activity for the oxidation of 4-hydroxybiphenyl (4-HB) at a reaction temperature of 60 degrees C when dimethylsulfoxide (DMSO) was employed as a co-solvent. Furthermore, the catalytic performance was successfully enhanced by the incorporation of a laccase mediator system (LMS) into the aqueous-DMSO media. The catalytic performance strongly depended on the type of mediator, and the highest activity was observed with 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) as mediator, suggesting the importance of the selection of a suitable mediator. It was verified that this mediator system is applicable to the oxidation of several biphenyl derivatives with hydroxyl groups. 相似文献
34.
(西北工业大学计算机学院,陕西西安,710072)【摘要】CARD架构适用于大规模、高查询率、每次查询的数据传输量较小的Ad-hoc网络,它的核心目标是降低网络资源发现能耗,延长网络生命周期。文章首先介绍了CARD架构的结构;然后,建立了该架构的数学模型,该模型以无线传感器网络为目标场景,并推导出CARD架构的能耗和查询成功率与各个参数之间的函数关系;最后,根据该模型对CARD架构的能耗和查询成功率进行了理论分析,为CARD架构的参数选择提供了可靠的依据,并为对架构的进一步优化打下了坚实基础。 相似文献
35.
The reforming of CH4 with CO2 over supported Rh catalysts has been studied over a range of temperatures (550–1000 K). A significant effect of the support on the catalytic activity was observed, where the order was Rh/Al2O3>Rh/TiO2>Rh/SiO2. The catalytic activity of Rh/SiO2 was promoted markedly by physical mixing of Rh/SiO2 with metal oxides such as Al2O3, TiO2, and MgO, indicating a synergetic effect. The role of the metal oxides used as the support and the physical mixture may be ascribed to the promotion in dissociation of CO2 on the surface of Rh, since the CH4 + CO2 reaction is first order in the pressure of CO2, suggesting that CO2 dissociation is the rate-determining step. The possible model of the synergetic effect was proposed. 相似文献
36.
针对水中非合作运动磁性目标的跟踪及参数估计问题,提出了一种基于Hopfield神经网络和磁梯度张量定位结合粒子滤波的方法对磁性目标进行跟踪,利用Hopfield神经网络和磁梯度张量定位为粒子滤波算法提供一部分更加优化的粒子,以增加粒子滤波算法中粒子的多样性,能够有效克服粒子退化现象,同时保证动态跟踪的速度和精度,并解决了远场磁定位中信噪比下降的问题.通过模拟仿真和磁性船模磁定位实验验证了算法的有效性,该算法可用于空中磁探潜和港口磁防御以及一般的UXO探测和定位问题,具有一定的军事和民用意义. 相似文献
37.
Patients with muscle weakness such as muscular dystrophy usually need someone’s assistance in their daily activities. In order to reduce the caregiver burden and to improve quality of life (QOL) of the patients, various robotic technologies have been developed. This paper presents an exoskeletal assistance system EMAS II for the patients, which assists the upper extremity for the purpose of daily activities such as eating, writing, or other desk works. The EMAS II assists four DOF; shoulder flexion-extension, shoulder abduction-adduction, shoulder medial-lateral rotation, and elbow flexion-extension. The EMAS II has three kinds of user interfaces which are operated by residual functions of the patients, because it is important for patients’ health and initiative to use the residual functions. In order to control the four DOFs exoskeleton system using the interfaces with less DOF, the EMAS II simulates upper limb motion patterns of healthy people. The patterns are modeled by extracting correlations between the height of the wrist joint and that of the elbow joint. Therefore, users have only to control the position of their wrist joint to do tasks at a table. Through an experiment with a healthy subject, the feasibility of meal assistance by the EMAS II was confirmed. Furthermore, the system was applied to a spinal muscular atrophy patient in a clinical trial to check the usability. The experimental results indicated that the EMAS II could support the patient’s upper extremity to do tasks at a table. 相似文献
38.
Yutaka Yawata Kensuke Toda Erika Setoyama Junji Fukuda Hiroaki Suzuki Hiroo Uchiyama Nobuhiko Nomura 《Journal of Bioscience and Bioengineering》2010,110(3):377-380
The feasibility of a method to monitor biofilm development non-destructively in a microfluidic device was addressed. Here, we report that biofilm growth could be non-destructively monitored by an image analysis technique based on modification of confocal reflection microscopy. 相似文献
39.
Shiro Kumano Kazuhiro Otsuka Junji Yamato Eisaku Maeda Yoichi Sato 《International Journal of Computer Vision》2009,83(2):178-194
In this paper, we propose a method for pose-invariant facial expression recognition from monocular video sequences. The advantage
of our method is that, unlike existing methods, our method uses a simple model, called the variable-intensity template, for
describing different facial expressions. This makes it possible to prepare a model for each person with very little time and
effort. Variable-intensity templates describe how the intensities of multiple points, defined in the vicinity of facial parts,
vary with different facial expressions. By using this model in the framework of a particle filter, our method is capable of
estimating facial poses and expressions simultaneously. Experiments demonstrate the effectiveness of our method. A recognition
rate of over 90% is achieved for all facial orientations, horizontal, vertical, and in-plane, in the range of ±40 degrees,
±20 degrees, and ±40 degrees from the frontal view, respectively.
Electronic Supplementary Material The online version of this article () contains supplementary material, which is available to authorized users. 相似文献
40.
Synthesis and hydrophilic property of polypropylene-graft-poly(polyethylene glycol-methacrylate) (PP-g-P(PEGMA)) 总被引:1,自引:0,他引:1
Nobuo Kawahara Junji Saito Shingo Matsuo Hideyuki Kaneko Tomoaki Matsugi Norio Kashiwa 《Polymer Bulletin》2010,64(7):657-666
Polypropylene-graft-poly(polyethylene glycol-methacrylate) (PP-g-P(PEGMA)), which is a hydrophobic-hydrophilic graft copolymer, was synthesized by a combination of an atom transfer radical polymerization (ATRP) of PEGMA with brominated polypropylene (PP-Br), which was synthesized from PP-OH prepared by metallocene-catalyzed copolymerization. Its structure was confirmed by 1H NMR and GPC analyses. Transmission electron microscope (TEM) micrographs of PP-g-P(PEGMA) revealed the nanometer level microphase-separation morphology between the PP segment and the P(PEGMA) segment. The obtained PP-g-P(PEGMA) showed water-absorbing property as well as thermostability. 相似文献