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61.
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
62.
The optimized incidence angle and magnetic field direction geometry of an InAs terahertz radiation emitter irradiated with femtosecond laser pulses in a magnetic field is reported. The optimum geometric layout is the magnetic field direction parallel to the semiconductor surface and at an incidence angle that is slightly larger than the Brewster angle. Additionally, we also observed a center frequency shift of terahertz radiation spectrum by changing the incidence angle of the excitation laser. 相似文献
63.
This paper describes a new type of self-organizing map (SOM) with twin units as opposed to the single unit type conventional SOM proposed by Kohonen. The present self-organizing map with twin units (TW-SOM) can describe a nonlinear input-output relation with high accuracy. It is applied to voice conversion problem from bone conduction voice to air conduction voice (nonlinear code vector mapping), and its superiority over the conventional method using Linde-Buzo-Gray (LBG) algorithm is discussed. The tone quality of the converted voice is examined not only from the quantization distortion viewpoint, but also from the auditory sensation viewpoint through actual listening tests. The enhancement of the tone quality was experimentally confirmed. 相似文献
64.
In this study, we design a learning environment that supports reflective activities for information seeking on the Web and evaluate its educational effects. The features of this design are: (1) to visualize the learners’ search processes as described, based on a cognitive schema, (2) to support two types of reflective activities, such as “reflection-in-action” and “reflection-on-action”, and (3) to facilitate reflective activities by comparing their own search processes to other learners’ search processes. We have conducted an experiment to investigate the effects of our design. The experimental results confirm that: (1) the participants’ search performance in the instructional group supported by our instructional design improved effectively than in the control group; (2) they changed their ideas about important activities when seeking information on the Web, and (3) they activated their search cycles more than the control group did. 相似文献
65.
N. Hashimoto A. Handa M. Nakagawa K. Obara H. Yano O. Ishikawa T. Hata 《Journal of Low Temperature Physics》2007,148(3-4):299-303
We have investigated the turbulence transition of the superfluid 4He flow generated by a vibrating wire. For a 1.2-kHz vibrating wire, we observed intermittent switchings between laminar and
turbulent flows. The switching rate decreases with increasing temperature above 100 mK, until no occurrence of the switchings
at 350 mK. For a 2.4-kHz vibrating wire, we find that the switching rate is much lower than that of the 1.2-kHz vibrating
wire even at low temperatures. This result indicates that a mechanism causing the switchings is influenced by the temperature
and the oscillation frequency of the superfluid flow. 相似文献
66.
Yasuyuki Kono Takehide Yano Tetsuro Chino Kaoru Suzuki Hiroshi Kanazawa 《Applied Artificial Intelligence》2013,27(4-5):487-518
Two requirements should be met in order to develop a practical multimodal interface system , i . e ., ( 1 ) integration of delayed arrival of data and ( 2 ) elimination of ambiguity in recognition results of each modality . This paper presents an efficient and generic methodology for interpretation of multimodal input to satisfy these requirements . The proposed methodology can integrate delayed - arrival data satisfactorily and efficiently interpret multimodal input that contains ambiguity . In the input interpretation the multimodal interpretation process is regarded as hypothetical reasoning , and the control mechanismof interpretation is formalized by applying the assumption - based truth maintenance system ( ATMS ). The proposed method is applied to an interface agent system that accepts multimodal input consisting of voice and direct indication gesture on a touch display . The systemcommunicates to the user through a human - like interface agent's three - dimensional motion image with facial expressions , gestures , and a synthesized voice . 相似文献
67.
Yuanbo Liu Soichi Nishiyama Tomohisa Yano 《International journal of remote sensing》2013,34(11):2121-2139
Although change detection algorithms for temporal remote sensing images have been compared using various datasets, there is no general agreement on their performance for separating change and no-change. This study compared image differencing, image ratioing, image regression, and principal component analysis (PCA) from a mathematical perspective. Error analysis showed that no-change pixels with errors are expected to be located within an error zone in bi-temporal space. Bi-temporal space consists of two temporal axes of target pixel values observed successively. All algorithms confine a no-change area to a zone delineating change and no-change pixels in the space. Image ratioing defines a fan-like sector as a no-change area, generally unsuitable for change detection. The other algorithms confine a no-change area to a strip-like zone. Image differencing defines a no-change zone with a fixed slope, leading to its inability to specify flexibly the error zone that varies with different conditions. In the examined case, image regression and standardized PCA (SPCA) achieved the best performance for change detection, followed by PCA, image differencing, and image ratioing. 相似文献
68.
In manufacturing facilities, shipping and receiving traditionally have been concentrated in one or two areas of the building. The widespread introduction of just-in-time shipping policies in US manufacturing companies during the past 15 years, as well as the common use of decentralized receiving in the Japanese automobile industry, has motivated the consideration (and occasionally the adoption) of dock configurations to support decentralized receiving (also known as perimeter receiving). By providing multiple access points along the perimeter of the building, decentralized receiving generally reduces the time and cost associated with moving purchased parts to the locations within the facility where they are used, but also results in increased cost of construction, maintenance, and operation for docks and associated truck access/egress, as well as additional interior floorspace requirements. We develop an optimization-based procedure to determine which of several possible dock areas to construct, how many doors or gates each should have, how many unloading and internal material handling staff should be assigned to each group, and which inbound materials each group should handle. We consider the amortized cost of constructing and equipping the docks, the amortized cost of material handling equipment to support the unloaders and material handlers, the cost of operating the material handling equipment, and labor costs for both unloading and internal material handling. 相似文献
69.
Growth of Lactobacillus bulgaricus in milk. 2. Characteristics of purine nucleotides, pyrimidine nucleotides, and nucleic acid synthesis 总被引:1,自引:0,他引:1
Lactobacillus bulgaricus incorporated exogenous guanine only into guanine nucleotides and not into adenine nucleotides. Lactobacillus bulgaricus lacks the ability to interconvert adenine nucleotides and guanine nucleotides. Biosynthesis of pyrimidine nucleotides from orotic acid was depressed by addition of guanosine monophosphate or adenosine monophosphate. Some step in pyrimidine biosynthesis from orotic acid may be negatively regulated by the intracellular amount of purine nucleotides. Lactobacillus bulgaricus could not grow in milk from which orotate was removed. This indicates that the activity of de novo pyrimidine synthesis is very low in this organism. When the intracellular amount of purine or pyrimidine base was limited, ribonucleic acid synthesis was markedly depressed, resulting in cell elongation, whereas deoxyribonucleic acid synthesis was not so much affected. 相似文献
70.
Tomohito Hamazaki Masaharu Urakaze Masahiro Makuta Akio Ozawa Yasuji Soda Hiroshi Tatsumi Saburo Yano Akira Kumagai 《Lipids》1987,22(12):994-998
The ethyl ester of eicosapentaenoic acid (EPA) is the only pure EPA-containing lipid available in bulk for oral administration.
However, there is doubt as to whether EPA ethyl ester can efficiently increase the plasma levels of EPA in comparison with
the ability of other kinds of EPA-containing lipids to do so. Therefore, two other kinds of EPA-containing lipids were prepared
to study the efficiency of oral administration of those lipids for increasing the EPA content in plasma phospholipids and
cholesteryl esters. EPA-containing lipids which were investigated were [A], 1,2,3-trieicosapentaenoyl-glycerol, [B] 2-eicosapentaenoyl-phosphatidylcholine
and [C] ethyl ester of EPA. An adjusted amount of lipids [A], [B] and [C] was administered to rats through a gastric tube
for 4 days (the first experiment) or for 10 days (the second experiment), and the fatty acid composition of plasma phospholipids
and cholesteryl esters was determined. In the first experiment, there were no significant differences in the efficiency for
increasing EPA levels in either phospholipids or cholesteryl esters among the lipids. In the second experiment, the EPA levels
of both plasma phospholipids and cholesteryl esters of rats administered ethyl ester of EPA were significantly higher than
those of rats administered 2-eicosapentaenoyl-phosphatidylcholine. The EPA levels of the rats administered 1,2,3-trieicosapentaenoylglycerol
were between the levels of the two groups mentioned above, but the differences in the EPA levels were not significant. Although
an ethyl ester-type molecule is not a naturally occurring lipid, ethyl ester of EPA is equal to 1,2,3-trieicosapentaenoyl-glycerol
and appears to be superior to 2-eicosapentaenoyl-phosphatidylcholine as to the efficiency for increasing EPA levels in total
plasma phospholipids and plasma cholesteryl esters. 相似文献