Papers - Takemura, Kenjiro

Tactile Quantification Method for Tissue based on Tactile Perception Characteristics of Human

Masaki Endo, Lisako Nobuyama, Koji Okomori, So Takahashi, Kenjiro Takemura

EUROHAPTICS2018  2018.06

Research paper (international conference proceedings), Joint Work, Last author, Corresponding author, Accepted

Tactile estimation of molded plastic plates based on the estimated impulse responses of mechanoreceptive units

Lisako Nobuyama, Yuta Kurashina, Kei Kawauchi, Koji Matsui, Kenjiro Takemura

Sensors (MDPI)  18 ( 5 ) 1588 2018.05

Research paper (scientific journal), Joint Work, Last author, Corresponding author, Accepted,  ISSN  14248220

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Application of Ultrasonic Vibration for Cell Culture

Kurashina Yuta, Takemura Kenjiro

Journal of the Robotics Society of Japan (The Robotics Society of Japan)  36 ( 3 ) 203 - 206 2018.04

Research paper (other academic), Joint Work, Last author, Corresponding author,  ISSN  0289-1824

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Understanding of electro-conjugate fluid flow with dibutyl decanedioate using numerical simulation—Calculating ion mobility using molecular dynamics simulation

Y. Kuroboshi, K. Takemura, K. Edamura

Sensors and Actuators, B: Chemical (Elsevier)  255 ( 1 ) 448 - 453 2018.02

Research paper (scientific journal), Joint Work, Corresponding author, Accepted,  ISSN  09254005

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An electro-conjugate fluid (ECF) is a type of dielectric functional fluid, which generates a powerful flow when a high direct-current voltage is applied. To date, ECF flow has been used in mechanical, chemical and biomedical applications because of its outstanding properties as a micro-pressure source for compact fluid-driven systems. However, the mechanism of ECF flow generation is not clarified and a basic understanding of ECF flow is required to progress ECF applications. We have developed the basic understanding of ECF flow generation through mathematical modeling, and have investigated electrical parameters theoretically. We have clarified microscopically the mechanism for ECF flow generation. We have proven the adequacy of the developed basic understanding by comparing visualized and computed flow characteristics. Furthermore, we have clarified the mechanism for ECF flow generation by comparing ionic transfer and ECF flow.

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A method for collecting single cell suspensions using an ultrasonic pump

Misa Nakao, Yuta Kurashina, Chikahiro Imashiro, and Kenjiro Takemura

IEEE Transactions on Biomedical Engineering (IEEE)  65 ( 1 ) 224 - 231 2018.01

Research paper (scientific journal), Joint Work, Last author, Corresponding author, Accepted,  ISSN  0018-9294

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Soft Robotics Using Electro-Conjugate Fluid

TAKEMURA Kenjiro

Journal of The Society of Instrument and Control Engineers (The Society of Instrument and Control Engineers)  57 ( 11 ) 775 - 779 2018

Research paper (scientific journal), Single Work, Lead author, Last author, Corresponding author,  ISSN  0453-4662

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Acoustic Cell Trapping to Rapidly Generate Three-dimensional Large Tissues

Misa Nakao, Chikahiro Imashiro, Yuta Kurashina, Kenjiro Takemura

TERMIS-AM2017  2017.12

Research paper (international conference proceedings), Joint Work, Last author, Corresponding author, Accepted

Tactile Evaluation Feedback System for Multi-layered Structure Inspired by Human Tactile Perception Mechanism

Iza Husna Mohamad Hashim, Shogo Kumamoto, Kenjiro Takemura, Takashi Maeno, Shin Okuda, Yukio Mori

Sensors (Multidisciplinary Digital Publishing Institute)  17 ( 11 ) 2601 - 2614 2017.11

Research paper (scientific journal), Joint Work, Corresponding author, Accepted,  ISSN  1424-8220

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Tactile sensation is one type of valuable feedback in evaluating a product. Conventionally, sensory evaluation is used to get direct subjective responses from the consumers, in order to improve the product's quality. However, this method is a time-consuming and costly process. Therefore, this paper proposes a novel tactile evaluation system that can give tactile feedback from a sensor's output. The main concept of this system is hierarchically layering the tactile sensation, which is inspired by the flow of human perception. The tactile sensation is classified from low-order of tactile sensation (LTS) to high-order of tactile sensation (HTS), and also to preference. Here, LTS will be correlated with physical measures. Furthermore, the physical measures that are used to correlate with LTS are selected based on four main aspects of haptic information (roughness, compliance, coldness, and slipperiness), which are perceived through human tactile sensors. By using statistical analysis, the correlation between each hierarchy was obtained, and the preference was derived in terms of physical measures. A verification test was conducted by using unknown samples to determine the reliability of the system. The results showed that the system developed was capable of estimating preference with an accuracy of approximately 80%.

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Effect of underwater ultrasound exposure on growth of plant roots and leaves

Yuta Kurashina, Tatsuya Yamashita, Shuichi Kurabayashi, Keita Ando, Kenjiro Takemura

IEEE International Ultrasonics Symposium, IUS (IEEE Computer Society)   2017.10

Research paper (international conference proceedings), Last author, Accepted,  ISSN  1948-5727

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Growth control is an important technique in plant markets, for appropriate shipping time of plants (e.g., flowers and fruits) allows for reducing production costs for post harvesting storage and pesticide. It is favorable to control plant growth without any chemicals
physical stresses are attractive candidates for this purpose. Here, we propose an ultrasound-based technique to control plant growth.

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Enzyme-free cell detachment mediated by resonance vibration with temperature modulation

Yuta Kurashina, Makoto Hirano, Chikahiro Imashiro, Kiichiro Totani, Jun Komotori, Kenjiro Takemura

Biotechnology & Bioengineering (John Wiley & Sons, Inc)  114 ( 10 ) 2279 - 2288 2017.10

Research paper (scientific journal), Joint Work, Accepted,  ISSN  0006-3592

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Cell detachment is an essential process in adherent cell culture. However, trypsinization, which is the most popular detachment technique used in culture, damages cellular membranes. Reducing cellular membrane damage during detachment should improve the quality of cell culture. In this article, we propose an enzyme-free cell detachment method based on resonance vibration with temperature modulation. We developed a culture device that can excite a resonance vibration and control temperature. We then evaluated the cell detachment ratio and the growth response, observed the morphology, and analyzed the cellular protein of the collected cellsmouse myoblast cell line (C2C12). With the temperature of 10 degrees C and the maximum vibration amplitude of 2m, 77.9% of cells in number were successfully detached compared with traditional trypsinization. The 72-h proliferation ratio of the reseeded cells was similar to that with trypsinization, whereas the proliferation ratio of proposed method was 12.6% greater than that of trypsinization after freezing and thawing. Moreover, the cells can be collected relatively intact and both intracellular and cell surface proteins in the proposed method were less damaged than in trypsinization. These results show that this method has definite advantages over trypsinization, which indicates that it could be applied to subcultures of cells that are more susceptible to trypsin damage for mass culture of sustainable clinical use. Biotechnol. Bioeng. 2017;114: 2279-2288. (c) 2017 Wiley Periodicals, Inc.

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Cover Image, Volume 114, Number 10, October 2017

Yuta Kurashina, Makoto Hirano, Chikahiro Imashiro, Kiichiro Totani, Jun Komotori, Kenjiro Takemura

Biotechnology and Bioengineering (John Wiley & Sons, Inc)  114 ( 10 ) i - i 2017.10

Research paper (scientific journal), Joint Work, Accepted

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Effective Arrangement of Electrodes for Electro-conjugate Fluid Flow Generation

Yuichiro Kuroboshi, Kenjiro Takemura, Kazuya Edamura

JFPS International Symposium on Fluid Power System  2017.10

Research paper (international conference proceedings), Joint Work, Corresponding author, Accepted

Detaching cells from cultivation flask using acoustic radiation pressure induced by Langevin transducer

Hanako Tauchi, Genichiro Fujii, Chikahiro Imashiro, Kenjiro Takemura

Acoustofluidics 2017  2017.08

Research paper (international conference proceedings), Joint Work, Last author, Corresponding author, Accepted

Single Cell Sorter Driven by Resonance Vibration of Cell Culture Substrate

Misa Nakao, Yuta Kurashina, Chikahiro Imashiro, Kenjiro Takemura

19th International Conference on Ultrasonics    3143 2017.06

Research paper (international conference proceedings), Joint Work, Last author, Corresponding author, Accepted

Acoustic Radiation Pressure Detaches Myoblast from Culture Substrate by Assistance of Serum-free Medium

Yuta Kurashina, Chikahiro Imashiro, Kiyoshi Ohnuma, Kenjiro Takemura

19th International Conference on Ultrasonics    3140 2017.06

Research paper (international conference proceedings), Joint Work, Last author, Corresponding author, Accepted

Droplet generating device for Droplet-based μTAS using electro-conjugate fluid

Yoshiki Iijima, Kenjiro Takemura, Kazuya Edamura

Smart Materials and Structures (IOP Publishing)  26 ( 5 ) 054002 2017.04

Research paper (scientific journal), Joint Work, Corresponding author, Accepted,  ISSN  0964-1726

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Droplet-based mu TAS, which carries out biochemical inspection and synthesis by handling samples as droplets on a single chip, has been attracting attentions in recent years. Although miniaturization of a chip is progressed, there are some problems in miniaturization of a whole system because of the necessity to connect syringe pumps to the chip. Thus, this study aims to realize a novel droplets generating device for droplet-based mu TAS using electro-conjugate fluid (ECF). The ECF is a dielectric liquid generating a powerful flow when subjected to high DC voltage. The ECF flow generation allows us to realize a tiny hydraulic power source. Using the ECF flow, we can develop a droplet generating device for droplet-based mu TAS by placing minute electrode pairs in flow channels. The device contains two channels filled with the ECF, which are dispersed and continuous phases meeting at a T-junction. When a sample in the dispersed phase is injected by the ECF flow to the continuous phase at T-junction, droplets are generated by shearing force between the two phases. We conducted droplet generating experiment and confirmed that droplets are successfully generated when the flow rate of the continuous phase is between 90 and 360 mm(3) s(-1), and the flow rate of the dispersed phase is between 10 and 40 mm(3) s(-1). We also confirmed that the droplet diameter and the droplet production rate are controllable by tuning the applied voltage to the electrode pairs.

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Ultrasonic Motor with Embedded Preload Mechanism for Miniaturization

Tomoya Kazumi, Yuta Kurashina, Kenjiro Takemura

The 7th International Conference on Manufacturing, Machine Design and Tribology  2017.04

Research paper (international conference proceedings), Joint Work, Last author, Corresponding author, Accepted

Tactile Sensor Inspired by Human Mechanoreceptors

Lisako Nobuyama, Iza Husna Mohamad Hashim, Yuta Kurashina, Kei Kawauchi, Koji Matsui, Kenjiro Takemura

The 7th International Conference on Manufacturing, Machine Design and Tribology  2017.04

Research paper (international conference proceedings), Joint Work, Last author, Corresponding author, Accepted

Efficient subculture process for adherent cells by selective collection using cultivation substrate vibration

Yuta Kurashina, Kenjiro Takemura, James Friend, Shogo Miyata, Jun Komotori

IEEE Transactions on Biomedical Engineering (IEEE)  64 ( 3 ) 580 - 587 2017.03

Research paper (scientific journal), Joint Work, Corresponding author, Accepted,  ISSN  0018-9294

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Cell detachment and reseeding are typical operations in cell culturing, often using trypsin exposure and pipetting, even though this process is known to damage the cells. Reducing the number of detachment and reseeding steps might consequently improve the overall quality of the culture, but to date this has not been an option. This study proposes the use of resonant vibration in the cell cultivation substrate to selectively release adherent calf chondrocyte cells: Some were released from the substrate and collected while others were left upon the substrate to grow to confluence as a subculture-without requiring reseeding. An out-of-plane vibration mode with a single nodal circle was used in the custom culture substrate. At a maximum vibration amplitude of 0.6 mu m, 84.9% of the cells adhering to the substrate were released after 3 min exposure, leaving a sufficient number of cells for passage and long-term cell culture, with the greatest cell concentration along the nodal circle where the vibration was relatively quiescent. The 72 h proliferation of the unreleased cells was 20% greater in number than cells handled using the traditional method of trypsin-EDTA (0.050%) release, pipette collection, and reseeding. Due to the vibration, it was possible to reduce the trypsin-EDTA used for selective release to only 0.025%, and in doing so the cell number after 72 h of proliferation was 42% greater in number than the traditional technique.

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Cell agglomeration in the wells of a 24-well plate using acoustic streaming

Yuta Kurashina, Kenjiro Takemura, James Friend

Lab on a Chip (Royal Society of Chemistry)  17 ( 5 ) 876 - 886 2017.02

Research paper (scientific journal), Joint Work, Accepted,  ISSN  1473-0197

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Cell agglomeration is essential both to the success of drug testing and to the development of tissue engineering. Here, a MHz-order acoustic wave is used to generate acoustic streaming in the wells of a 24-well plate to drive particle and cell agglomeration. Acoustic streaming is known to manipulate particles in microfluidic devices, and even provide concentration in sessile droplets, but concentration of particles or cells in individual wells has never been shown, principally due to the drag present along the periphery of the fluid in such a well. The agglomeration time for a range of particle sizes suggests that shear-induced migration plays an important role in the agglomeration process. Particles with a diameter of 45 mu m agglomerated into a suspended pellet under exposure to 2.134 MHz acoustic waves at 1.5 W in 30 s. Additionally, BT-474 cells also agglomerated as adherent masses at the center bottom of the wells of tissue-culture treated 24-well plates. By switching to low cell binding 24-well plates, the BT-474 cells formed suspended agglomerations that appeared to be spheroids, fully fifteen times larger than any cell agglomerates without the acoustic streaming. In either case, the viability and proliferation of the cells were maintained despite acoustic irradiation and streaming. Intermittent excitation was effective in avoiding temperature excursions, consuming only 75 mW per well on average, presenting a convenient means to form fully three-dimensional cellular masses potentially useful for tissue, cancer, and drug research.

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