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Kenji Kikuchi

Section

Graduate School of Engineering

Job title

Associate Professor

Degree

博士（工学）（東洋大学）
修士（工学）（東洋大学）

researchmap

https://researchmap.jp/7000010036

J-GLOBAL ID

201401064888133859

e-Rad No.

00553801

Committee Memberships 21

可視化情報学会　理事（第31期、第32期）

2019/06 - Present
可視化情報学会学会誌編集委員会　オンライン担当委員

2012/01 - Present
可視化情報学会学会誌編集委員会　オンライン担当委員

2012/01 - Present
第35回日本機械学会バイオエンジニアリング部門講演会実行委員（幹事）

2022/06 - 2023/06
可視化情報学会主催第50回可視化情報シンポジウム実行委員

2021/07 - 2022/08
日本機械学会バイオエンジニアリング部門　広報委員

2020/03 - 2022/03
日本機械学会バイオエンジニアリング部門　部門代議員

2018/03 - 2020/02
International Conference on Fluid Mechanics2018　Local committee

2017/01 - 2018/09
日本機械学会東北支部講演会　実行委員

2017/08 - 2018/03
日本機械学会流体工学部門 P-SCC13マイクロ熱流動に関する調査研究分科会　委員

2015/10 - 2017/09
可視化情報学会主催第45回可視化情報シンポジウム　実行委員

2016/08 - 2017/07
日本機械学会流体工学部門 P-SCD382 せん断流の多様な機能の探求と先端科学技術への応用に関する研究分科会　委員

2013/10 - 2016/09
可視化情報学会主催第44回可視化情報シンポジウム　実行委員

2015/08 - 2016/07
可視化情報学会主催第43回可視化情報シンポジウム　実行委員

2014/08 - 2015/07
可視化情報学会主催第42回可視化情報シンポジウム　幹事

2013/08 - 2014/07
VSJ The 16th International Symposium on Flow Visualization　Local Organizing Committee

2013/06 - 2014/07
可視化情報学会主催 The 16th International Symposium on Flow Visualization　Local Organizing Committee

2013/06 - 2014/07
日本機械学会主催流体工学部門 P-SCD366 噴流，後流，およびはく離流れの基礎と先進的応用に関する研究分科会　委員

2011/10 - 2013/09
可視化情報学会主催第41回可視化情報シンポジウム　幹事

2012/08 - 2013/07
JSME International Conference on Jet, Wake and Separated Flow (ICJWSF2013)　Local Organizing Committee

2012/04 - 2013/06
日本機械学会流体工学部門主催 International Conference on Jet, Wake and Separated Flow (ICJWSF2013)　Local Organizing Committee

2012/04 - 2013/06

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Professional Memberships 4

アメリカ物理学会
THE VISUALIZATION SOCIETY OF JAPAN
THE JAPAN SOCIETY OF FLUID MECHANICS
THE JAPAN SOCIETY OF MECHANICAL ENGINEERS

Research Interests 1

Bio Fluid Dynamics, Biomechanics, Visualization of Bio Flow, Proto-intelligence

Research Areas 1

Manufacturing technology (mechanical, electrical/electronic, chemical engineering) / Fluid engineering /

Awards 11

可視化情報学会功労賞

2023/05　可視化情報学会
Tohoku University Distinguished Researcher

2020/04　Tohoku University
文部科学大臣表彰若手科学者賞

2018/04　文部科学省
生体医工学シンポジウムベストレビュワーアワード

2017/09/15　日本生体医工学会
World Congress on Engineering 2016 Best Paper Awards

2016/10/13　International Association of Engineering
可視化情報シンポジウムアートコンテスト金賞

2015/04/21　可視化情報シンポジウム実行委員会
可視化情報学会映像賞

2015/04/21　可視化情報学会
可視化情報学会奨励賞(研究)

2015/04/21　可視化情報学会
日本機械学会賞奨励賞(研究)

2015/04/17　日本機械学会
Measurement Science and Technology, Highlights of 2011-2012 Collection

2012/08/16　IOP Publishing
2007年生体医工学シンポジウムベストリサーチアワード

2007/09/21　日本生体医工学会

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Papers 84

Reply to Larsen and Riisgård: Fluid dynamics of choanocyte chambers

Takumi Ogawa, Shuji Koyama, Toshihiro Omori, Kenji Kikuchi, Hélène de Maleprade, Raymond E. Goldstein, Takuji Ishikawa

Proceedings of the National Academy of Sciences　2025/06/17

DOI： 10.1073/pnas.2507566122 　
Hydrodynamic confinement of bacteria within intestinal folds

Jinyou Yang, Toshihiro Omori, Kenji Kikuchi, Takuji Ishikawa

Proceedings of the Royal Society B: Biological Sciences　2025/04

DOI： 10.1098/rspb.2024.3068 　
The architecture of sponge choanocyte chambers is well adapted to mechanical pumping functions

Takumi Ogawa, Shuji Koyama, Toshihiro Omori, Kenji Kikuchi, Hélène de Maleprade, Raymond E. Goldstein, Takuji Ishikawa

Proceedings of the National Academy of Sciences　2025/03/25

DOI： 10.1073/pnas.2421296122 　
Reduction of aerosol and droplet dispersions using intraoral and extraoral vacuums for dental treatments with face-up, diagonal and upright positions

Tomonari Kajita, Kenji Kikuchi, Hiromitsu Morishima, Jun Watanabe, Yoko Iwamatsu-Kobayashi, Hiroyasu Kanetaka, Wataru Yashiro, Kensuke Yamauchi, Hiroshi Egusa

BMC Oral Health　24　(1)　2024/11/17
Publisher: Springer Science and Business Media LLC
DOI： 10.1186/s12903-024-04911-5 　

eISSN： 1472-6831
気管チューブによるベンチュリー効果が、ペンデルフト現象に与える影響 secondary publication(abridged translation)

高橋和博, 外山裕章, 江島豊, Yang Jinyou, 菊地謙次, 石川拓司, 山内正憲

呼吸療法　41　(1)　107-115　2024/05
Publisher: (一社)日本呼吸療法医学会
eISSN： 2759-4289
Bacterial accumulation in intestinal folds induced by physical and biological factors. International-journal

Jinyou Yang, Toma Isaka, Kenji Kikuchi, Keiko Numayama-Tsuruta, Takuji Ishikawa

BMC biology　22　(1)　76-76　2024/04/05

DOI： 10.1186/s12915-024-01874-5 　

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BACKGROUND: The gut microbiota, vital for host health, influences metabolism, immune function, and development. Understanding the dynamic processes of bacterial accumulation within the gut is crucial, as it is closely related to immune responses, antibiotic resistance, and colorectal cancer. We investigated Escherichia coli behavior and distribution in zebrafish larval intestines, focusing on the gut microenvironment. RESULTS: We discovered that E. coli spread was considerably suppressed within the intestinal folds, leading to a strong physical accumulation in the folds. Moreover, a higher concentration of E. coli on the dorsal side than on the ventral side was observed. Our in vitro microfluidic experiments and theoretical analysis revealed that the overall distribution of E. coli in the intestines was established by a combination of physical factor and bacterial taxis. CONCLUSIONS: Our findings provide valuable insight into how the intestinal microenvironment affects bacterial motility and accumulation, enhancing our understanding of the behavioral and ecological dynamics of the intestinal microbiota.
Glucose stockpile in the intestinal apical brush border in C. elegans

Takumi Saito, Kenji Kikuchi, Takuji Ishikawa

Biochemical and Biophysical Research Communications　706　2024/04

DOI： 10.1016/j.bbrc.2024.149762 　

ISSN： 0006-291X

eISSN： 1090-2104
The Architecture of Sponge Choanocyte Chambers Maximizes Mechanical Pumping Efficiency

Takumi Ogawa, Shuji Koyama, Toshihiro Omori, Kenji Kikuchi, Hélène de Maleprade, Raymond E. Goldstein, Takuji Ishikawa

2024/02/22

DOI： 10.1101/2024.02.22.581376 　
High shear flow prevents bundling of bacterial flagella and induces lateral migration away from a wall

Jinyou Yang, Kenji Kikuchi, Takuji Ishikawa

Communications Physics　6　(1)　2023/12

DOI： 10.1038/s42005-023-01471-y 　

eISSN： 2399-3650
Effectiveness of substantial shortening of the endotracheal tube for decreasing airway resistance and increasing tidal volume during pressure-controlled ventilation in pediatric patients: a prospective observational study. International-journal Peer-reviewed

Kazuhiro Takahashi, Hiroaki Toyama, Ryosuke Kubo, Norifumi Yoshida, Yutaka Ejima, Kenji Kikuchi, Takuji Ishikawa, Masanori Yamauchi

Journal of clinical monitoring and computing　2023/06/08

DOI： 10.1007/s10877-023-01038-w 　

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The endotracheal tubes (ETTs) used for children have a smaller inner diameter. Accordingly, the resistance across ETT (RETT) is higher. Theoretically, shortening the ETTs can decrease total airway resistance (Rtotal), because Rtotal is sum of RETT and patient's airway resistance. However, the effectiveness of ETT shortening for mechanical ventilation in the clinical setting has not been reported. We assessed the effectiveness of shortening a cuffed ETT for decreasing Rtotal, and increasing tidal volume (TV), and estimated the RETT/Rtotal ratio in children. In anesthetized children in a constant pressure-controlled ventilation setting, Rtotal and TV were measured with a pneumotachometer before and after shortening a cuffed ETT. In a laboratory experiment, the pressure gradient across the original length, shortened length, and the slip joint alone of the ETT were measured. We then determined the RETT/Rtotal ratio using the above results. The clinical study included 22 children. The median ETT percent shortening was 21.7%. Median Rtotal was decreased from 26 to 24 cmH2O/L/s, and median TV was increased by 6% after ETT shortening. The laboratory experiment showed that ETT length and the pressure gradient across ETT are linearly related under a certain flow rate, and approximately 40% of the pressure gradient across the ETT at its original length was generated by the slip joint. Median RETT/Rtotal ratio were calculated as 0.69. The effectiveness of ETT shortening on Rtotal and TV was very limited, because the resistance of the slip joint was very large.
Visualization of droplets and aerosols in simulated dental treatments to clarify the effectiveness of oral suction devices. Peer-reviewed

Jun Watanabe, Yoko Iwamatsu-Kobayashi, Kenji Kikuchi, Tomonari Kajita, Hiromitsu Morishima, Kensuke Yamauchi, Wataru Yashiro, Hidekazu Nishimura, Hiroyasu Kanetaka, Hiroshi Egusa

Journal of prosthodontic research　2023/02/22

DOI： 10.2186/jpr.JPR_D_23_00013 　

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PURPOSE: The hazards of aerosols generated during dental treatments are poorly understood. This study aimed to establish visualization methods, discover conditions for droplets/aerosols generated in simulating dental treatments and identify the conditions for effective suction methods. METHODS: The spreading area was evaluated via image analysis of the droplets/aerosols generated by a dental air turbine on a mannequin using a light emitting diode (LED) light source and high-speed camera. The effects of different bur types and treatment sites, reduction effect of intra-oral suction (IOS) and extra-oral suction (EOS) devices, and effect of EOS installation conditions were evaluated. RESULTS: Regarding the bur types, a bud-shaped bur on the air turbine generated the most droplets/aerosols compared with round-shaped, round end-tapered, or needle-tapered burs. Regarding the treatment site, the area of droplets/aerosols produced by an air turbine from the palatal plane of the anterior maxillary teeth was significantly higher. The generated droplet/aerosol area was reduced by 92.1% by using IOS alone and 97.8% by combining IOS and EOS. EOS most effectively aspirated droplets/aerosols when placed close (10 cm) to the mouth in the vertical direction (0°). CONCLUSIONS: The droplets/aerosols generated by an air turbine could be visualized using an LED light and a high-speed camera in simulating dental treatments. The bur shape and position of the dental air turbine considerably influenced droplet/aerosol diffusion. The combined use of IOS and EOS at a proper position (close and perpendicular to the mouth) facilitated effective diffusion prevention to protect the dental-care environment.
Endotracheal tube, by the venturi effect, reduces the efficacy of increasing inlet pressure in improving pendelluft. International-journal Peer-reviewed

Kazuhiro Takahashi, Hiroaki Toyama, Yutaka Ejima, Jinyou Yang, Kenji Kikuchi, Takuji Ishikawa, Masanori Yamauchi

PloS one　18　(9)　e0291319　2023

DOI： 10.1371/journal.pone.0291319 　

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In mechanically ventilated severe acute respiratory distress syndrome patients, spontaneous inspiratory effort generates more negative pressure in the dorsal lung than in the ventral lung. The airflow caused by this pressure difference is called pendelluft, which is a possible mechanisms of patient self-inflicted lung injury. This study aimed to use computer simulation to understand how the endotracheal tube and insufficient ventilatory support contribute to pendelluft. We established two models. In the invasive model, an endotracheal tube was connected to the tracheobronchial tree with 34 outlets grouped into six locations: the right and left upper, lower, and middle lobes. In the non-invasive model, the upper airway, including the glottis, was connected to the tracheobronchial tree. To recreate the inspiratory effort of acute respiratory distress syndrome patients, the lower lobe pressure was set at -13 cmH2O, while the upper and middle lobe pressure was set at -6.4 cmH2O. The inlet pressure was set from 10 to 30 cmH2O to recreate ventilatory support. Using the finite volume method, the total flow rates through each model and toward each lobe were calculated. The invasive model had half the total flow rate of the non-invasive model (1.92 L/s versus 3.73 L/s under 10 cmH2O, respectively). More pendelluft (gas flow into the model from the outlets) was observed in the invasive model than in the non-invasive model. The inlet pressure increase from 10 to 30 cmH2O decreased pendelluft by 11% and 29% in the invasive and non-invasive models, respectively. In the invasive model, a faster jet flowed from the tip of the endotracheal tube toward the lower lobes, consequently entraining gas from the upper and middle lobes. Increasing ventilatory support intensifies the jet from the endotracheal tube, causing a venturi effect at the bifurcation in the tracheobronchial tree. Clinically acceptable ventilatory support cannot completely prevent pendelluft.
Reciprocating intestinal flows enhance glucose uptake in C. elegans. International-journal Peer-reviewed

Yuki Suzuki, Kenji Kikuchi, Keiko Numayama-Tsuruta, Takuji Ishikawa

Scientific reports　12　(1)　15310-15310　2022/09/21

DOI： 10.1038/s41598-022-18968-1 　

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Despite its physiological and pathological importance, the mechanical relationship between glucose uptake in the intestine and intestinal flows is unclear. In the intestine of the nematode Caenorhabditis elegans, the defecation motor program (DMP) causes reciprocating intestinal flows. Although the DMP is frequently activated in the intestines, its physiological function is unknown. We evaluated the mechanical signature of enhanced glucose uptake by the DMP in worms. Glucose uptake tended to increase with increasing flow velocity during the DMP because of mechanical mixing and transport. However, the increase in input energy required for the DMP was low compared with the calorie intake. The findings suggest that animals with gastrointestinal motility exploit the reciprocating intestinal flows caused by peristalsis to promote nutrient absorption by intestinal cells.
歯科治療で発生するエアロゾル挙動の可視化

小林洋子, 渡辺隼, 梶田倫功, 山内健介, 金高弘恭, 江草宏, 五十嵐薫, 矢代航, 菊地謙次, 西村秀一, 森島浩允, 佐藤舜, 菅井優生

東北大学歯学雑誌　39/40/41　(2/1-2/1)　49-49　2022/06
Publisher: 東北大学歯学会
ISSN： 0287-3915
Rheotaxis and migration of an unsteady microswimmer Peer-reviewed

T. Omori, K. Kikuchi, M. Schmitz, M. Pavlovic, C.-H. Chuang, T. Ishikawa

Journal of Fluid Mechanics　930　2022/01/10
Publisher: Cambridge University Press (CUP)
DOI： 10.1017/jfm.2021.921 　

ISSN： 0022-1120

eISSN： 1469-7645

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Rheotaxis and migration of cells in a flow field have been investigated intensively owing to their importance in biology, physiology and engineering. In this study, first, we report our experiments showing that the microalgae Chlamydomonas can orient against the channel flow and migrate to the channel centre. Second, by performing boundary element simulations, we demonstrate that the mechanism of the observed rheotaxis and migration has a physical origin. Last, using a simple analytical model, we reveal the novel physical mechanisms of rheotaxis and migration, specifically the interplay between cyclic body deformation and cyclic swimming velocity in the channel flow. The discovered mechanism can be as important as phototaxis and gravitaxis, and likely plays a role in the movement of other natural microswimmers and artificial microrobots with non-reciprocal body deformation.
Influence of Respiratory Gas Density on Tidal Volume During Pressure-Controlled Ventilation: A Laboratory Investigation and Observational Study in Children. Peer-reviewed

Kazuhiro Takahashi, Hiroaki Toyama, Yutaro Funahashi, Shin Kawana, Yutaka Ejima, Kenji Kikuchi, Takuji Ishikawa, Masanori Yamauchi

The Tohoku journal of experimental medicine　256　(4)　271-281　2022

DOI： 10.21203/rs.3.rs-711979/v1 　

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Fluid mechanics show that high-density gases need more energy while flowing through a tube. Thus, high-density anesthetic gases consume more energy to flow and less energy for lung inflation during general anesthesia. However, its impact has not been studied. Therefore, this study aimed to investigate the effects of high-density anesthetic gases on tidal volume in laboratory and clinical settings. In the laboratory study, a test lung was ventilated at the same pressure-controlled ventilation with 22 different gas compositions (density range, 1.22-2.27 kg/m3) using an anesthesia machine. A pneumotachometer was used to record the tidal volume of the test lung and the respiratory gas composition; it showed that the tidal volume of the test lung decreased as the respiratory gas density increased. In the clinical study, the change in tidal volume per body weight, accompanied by gas composition change (2% sevoflurane in oxygen and with 0-30-60% of N2O), was recorded in 30 pediatric patients. The median tidal volume per body weight decreased by 10% when the respiratory gas density increased from 1.41 kg/m3 to 1.70 kg/m3, indicating a significant between-group difference (P < 0.0001). In both settings, an increase in respiratory gas density decreased the tidal volume during pressure-controlled ventilation, which could be explained by the fluid dynamics theory. This study clarified the detailed mechanism of high-density anesthetic gas reduced the tidal volume during mechanical ventilation and revealed that this phenomenon occurs during pediatric anesthesia, which facilitates further understanding of the mechanics of ventilation during anesthesia practice and respiratory physiology.
Microbial Brazil nut effect. International-journal Peer-reviewed

Atul Srivastava, Kenji Kikuchi, Takuji Ishikawa

Soft matter　17　(46)　10428-10436　2021/12/01

DOI： 10.1039/d1sm01327k 　

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The Brazil nut effect (BNE) is a counter-intuitive process of segregation of a large object inside a vibrated granular medium (GM), which has been studied widely by subjecting GMs to various kinds of shears and vibrations. In this article, we report a new kind of BNE which occurs as a consequence of granular fluctuations induced by microbe-generated gas bubbles. We call it the 'microbial Brazil nut effect'. The paper demonstrates microbial BNE for a bidisperse granular mixture as well as for intruder segregation. Furthermore, using X-ray μCT and a simple scaling argument for segregation velocity, the paper clarifies the transport mechanics of an intruder inside a bubbly granular bed. We think the reported phenomenon should be ubiquitous in the microbe-populated wet sandy floors of waterbodies and may have some implication on the distribution of material near the floors.
Non-biodegradable objects may boost microbial growth in water bodies by harnessing bubbles Peer-reviewed

Atul Srivastava, Kenji Kikuchi, Takuji Ishikawa

Royal Society Open Science　8　(210646)　1-15　2021/09

DOI： 10.1098/rsos.210646 　
Bacterial biomechanics-From individual behaviors to biofilm and the gut flora. International-journal Peer-reviewed

Takuji Ishikawa, Toshihiro Omori, Kenji Kikuchi

APL bioengineering　4　(4)　041504-041504　2020/12

DOI： 10.1063/5.0026953 　

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Bacteria inhabit a variety of locations and play important roles in the environment and health. Our understanding of bacterial biomechanics has improved markedly in the last decade and has revealed that biomechanics play a significant role in microbial biology. The obtained knowledge has enabled investigation of complex phenomena, such as biofilm formation and the dynamics of the gut flora. A bottom-up strategy, i.e., from the cellular to the macroscale, facilitates understanding of macroscopic bacterial phenomena. In this Review, we first cover the biomechanics of individual bacteria in the bulk liquid and on surfaces as the base of complex phenomena. The collective behaviors of bacteria in simple environments are next introduced. We then introduce recent advances in biofilm biomechanics, in which adhesion force and the flow environment play crucial roles. We also review transport phenomena in the intestine and the dynamics of the gut flora, focusing on that in zebrafish. Finally, we provide an overview of the future prospects for the field.
The bubble-induced population dynamics of fermenting yeasts. International-journal Peer-reviewed

Atul Srivastava, Kenji Kikuchi, Takuji Ishikawa

Journal of the Royal Society, Interface　17　(172)　20200735-20200735　2020/11

DOI： 10.1098/rsif.2020.0735 　

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Bubble-induced transport is a ubiquitous natural and industrial phenomenon. In brewery, such transport occurs due to gas bubbles generated through anaerobic fermentation by yeasts. Two major kinds of fermentation viz. top (ale) and bottom (lager) fermentation, display a difference in their yeast distributions inside a sugar broth. The reason for this difference is believed to be yeast-bubble adhesion arising due to surface hydrophobicity of the yeast cell wall; however, the physical mechanism is still largely a mystery. In this report, through in vivo experiments, we develop a novel theoretical model for yeast distribution based on the general conservation law. This work clarifies that bubble-induced diffusion is the dominant transport mechanism in bottom-fermentation by lagers whereas, yeast-bubble adhesion plays a leading role in transporting ales in top-fermentation, thereby corroborating the centuries-old belief regarding distribution difference in yeast population in two kinds of fermentation.
Vulnerability of the skin barrier to mechanical rubbing. International-journal Peer-reviewed

Kenji Kikuchi, Shunsuke Shigeta, Keiko Numayama-Tsuruta, Takuji Ishikawa

International journal of pharmaceutics　587　119708-119708　2020/07/31

DOI： 10.1016/j.ijpharm.2020.119708 　

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Skin barrier function is the battlefront for preventing permeation of harmful substances and infectious diseases. However, it can be destroyed by mechanical forces, as shown in many studies. Excess rubbing may increase the permeability of the skin to aqueous material. Although the skin barrier plays an important physiological role in humans, the vulnerability of skin to mechanical rubbing is poorly understood. Therefore, we investigated the effects of rubbing on the skin in vitro; skin damage was quantified by laser-induced fluorescence. Microscopic observation showed that keratinocytes in the stratum corneum sustained traumatic damage, which reduced the barrier function in that region. The permeability of the skin to an aqueous solution increased with rubbing frequency and load, and rubbing markedly reduced the barrier function of the stratum corneum. To understand the mechanisms underlying the skin damage, we developed a simple mathematical model assuming that the skin is a viscoelastic material. We hypothesized that the increased skin permeability was caused by the damage sustained by keratinocytes in the stratum corneum, and that the permeability was proportional to the time-averaged strain. Our theoretical results showed quantitative agreement with the experimental results and illustrated that rubbing and strain relaxation play key roles in rubbing-induced permeation.
How do C. elegans worms survive in highly viscous habitats? International-journal Peer-reviewed

Yuki Suzuki, Kenji Kikuchi, Keiko Numayama-Tsuruta, Takuji Ishikawa

The Journal of experimental biology　2020/06/25

DOI： 10.1242/jeb.224691 　

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The nematode Caenorhabditis elegans is a filter feeder, which lives in various viscous habitats such as soil, the intestines of slugs, and rotting materials such as fruits and stems. C. elegans draws in suspensions of bacteria and separates bacteria from water using the pharyngeal pump. Although these worms often live in highly viscous habitats, it is still unclear how they survive in these environments by eating bacteria. In this study, we investigated the effects of suspension viscosity on the survival rate of malnutritioned worms by combining live imaging and scaling analyses. We found that survival rate decreased with increases in viscosity because the high viscosity suppressed the amount of food ingested. The same tendency was found in two feeding defective mutants, eat-6(ad467) and eat-6(ad997). We also found that the high viscosity weakened pump function, but the velocities in the pharynx were not zero, even in the most viscous suspensions. Finally, we estimated the amount of ingested food using scaling analyses, which provided a master curve of the experimental survival rates. These results illustrate that the survival rate of C. elegans worms is strongly dependent on the ingested bacteria per unit time associated with physical environments, such as the viscosity of food suspensions and the number density of bacteria. The pump function of the C. elegans pharynx is not completely lost even in fluids that have 105 times higher viscosity than water, which may contribute to their ability to survive around the world in highly viscous environments.
Mechanical roles of anterograde and retrograde intestinal peristalses after feeding in a larval fish (Danio rerio). International-journal Peer-reviewed

Kenji Kikuchi, Hyeongtak Noh, Keiko Numayama-Tsuruta, Takuji Ishikawa

American journal of physiology. Gastrointestinal and liver physiology　318　(6)　G1013-G1021　2020/06/01

DOI： 10.1152/ajpgi.00165.2019 　

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Transport in gut is important, not only for digestion, metabolism, and nutrient uptake, but also for microbiotic circumstance in the digestive tract; however, the effects of mixing and pumping in the intestine have not been fully clarified. Therefore, in this study, we quantitatively explored intestinal mixing and pumping, represented using a dispersion coefficient and pressure rise in zebrafish larvae, which is a model organism for vertebrate digestive studies, over time by measuring transport phenomena after feeding. Here we provide the first quantitative evidence of the roles of anterograde and retrograde intestinal peristalses in the larval fish of Danio rerio after feeding in terms of digestive pumping and mixing functions by an in vivo imaging of intestinal propagation waves in the larval intestine. Peristaltic velocities in the anterior and posterior intestines change considerably after feeding for 5 h, while the intervals and amplitudes remain almost constant. The intestinal transport is successively visualized after feeding to elimination. Moreover, the particle tracking velocimetry in the chyme leads our quantitative understanding of outstanding mixing and pumping functions in the anterior and posterior intestines by adopting physical parameters of diffusivity and pressure rise, respectively. From scaling analysis, we found that the anterior intestine maintains mixing for 5 h from feeding, whereas the posterior intestine activates gradually pumping up. These results suggest that time change of pumping and mixing functions of intestinal peristalsis could considerably influence the nutrient uptake and microbiotic circumstance in the larval fish intestine.NEW & NOTEWORTHY Transport in gut is important, not only for digestion, metabolism, and nutrient uptake, but also for microbiotic circumstance; however, hydrodynamic effects in the intestine have not been fully clarified. We provide the first quantitative evidence of the mechanical roles of anterograde and retrograde intestinal peristalses in the larval fish of Danio rerio by adopting physical parameters of diffusivity and pressure rise. The intestine transitionally regulates mixing and pumping functions by peristaltic propagations after feeding.
Cilia and centrosomes: Ultrastructural and mechanical perspectives. International-journal Peer-reviewed

Takuji Ishikawa, Hironori Ueno, Toshihiro Omori, Kenji Kikuchi

Seminars in cell & developmental biology　110　61-69　2020/04/16
Publisher: Elsevier BV
DOI： 10.1016/j.semcdb.2020.03.007 　

ISSN： 1084-9521

eISSN： 1096-3634
The shape effect of flagella is more important than bottom-heaviness on passive gravitactic orientation in Chlamydomonas reinhardtii. International-journal Peer-reviewed

Azusa Kage, Toshihiro Omori, Kenji Kikuchi, Takuji Ishikawa

The Journal of experimental biology　223　(Pt 5)　2020/03/03

DOI： 10.1242/jeb.205989 　

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The way the unicellular, biflagellated, green alga Chlamydomonas orients upward has long been discussed in terms of both mechanics and physiology. In this study, we focus on the mechanics, i.e. the 'passive' mechanisms, of gravitaxis. To rotate the body upwards, cellular asymmetry is critical. Chlamydomonas can be depicted as a nearly spherical cell body with two anterior, symmetric flagella. The present study looks at the question of whether the existence of the flagella significantly affects torque generation in upward reorientation. The 'density asymmetry model' assumes that the cell is spherical and bottom-heavy and that the shape and weight of the flagella are negligible, while the 'shape asymmetry model' considers the shape of the flagella. Both our experimental and simulation results revealed a considerable contribution from shape asymmetry to the upward orientation of Chlamydomonas reinhardtii, which was several times larger than that of density asymmetry. From the experimental results, we also quantified the extent of bottom-heaviness, i.e. the distance between the centers of gravity and the figure when the cell body is assumed to be spherical. Our estimation was approximately 30 nm, only one-third of previous assumptions. These findings indicate the importance of the viscous drag of the flagella to the upward orientation, and thus negative gravitaxis, in Chlamydomonas.
Particle selectivity of filtering by C. elegans Peer-reviewed

Yuki Suzuki, Kenji Kikuchi, Keiko Tsuruta-Numayama, Takuji Ishikawa

THEORETICAL AND APPLIED MECHANICS LETTERS　9　(2)　61-65　2019/03

DOI： 10.1016/j.taml.2019.02.001 　

ISSN： 2095-0349
Depth measurement of molecular permeation using inclined confocal microscopy. International-journal Peer-reviewed

Kenji Kikuchi, Shunsuke Shigeta, Takuji Ishikawa

PloS one　14　(3)　e0214504　2019

DOI： 10.1371/journal.pone.0214504 　
Burst mode pumping: A new mechanism of drinking in mosquitoes Peer-reviewed

Kenji Kikuchi, Mark A. Stremler, Souvick Chatterjee, Wah-Keat Lee, Osamu Mochizuki, John J. Socha

Scientific Reports　8　(1)　4885　2018/12/01

DOI： 10.1038/s41598-018-22866-w 　

ISSN： 2045-2322
Collective spreading of red blood cells flowing in a microchannel. International-journal

Cheng-Hsi Chuang, Kenji Kikuchi, Hironori Ueno, Keiko Numayama-Tsuruta, Takami Yamaguchi, Takuji Ishikawa

Journal of biomechanics　69　64-69　2018/03/01

DOI： 10.1016/j.jbiomech.2018.01.009 　

ISSN： 0021-9290
Biomechanics of Tetrahymena escaping from a dead end Peer-reviewed

Takuji Ishikawa, Kenji Kikuchi

Proceedings of the Royal Society B: Biological Sciences　285　(1873)　2018/02/28
Publisher: Royal Society Publishing
DOI： 10.1098/rspb.2017.2368 　

ISSN： 1471-2954 0962-8452
Biomechanics of Tetrahymena escaping from dead ends

TAKUJI ISHIKAWA, KENJI KIKUCHI

Bulletin of the American Physical Society DFD2017　62　(14)　407-407　2017/11
Effect of Fluid Viscosity on the Cilia-Generated Flow on a Mouse Tracheal Lumen Peer-reviewed

Kenji Kikuchi, Tomofumi Haga, Keiko Numayama-Tsuruta, Hironori Ueno, Takuji Ishikawa

ANNALS OF BIOMEDICAL ENGINEERING　45　(4)　1048-1057　2017/04

DOI： 10.1007/s10439-016-1743-y 　

ISSN： 0090-6964

eISSN： 1573-9686
Sponge Pump

HÉLÈNE DE MALEPRADE, KENJI KIKUCHI, RAYMOND E. GOLDSTEIN

Flow17　2017
Transdermal Drug Delivery Enhancement by Unidirectional Skin Extention

Sho Sugawara, Kenji Kikuchi, Shunsuke Shigeta, Keiko Numayama-Tsuruta, Takuji Ishikawa

The 26th Congress of the International Society of Biomechanics　2017
ViscousLload Change the Ciliary Force and Flow on a Tracheal Lumen

Takuji Ishikawa, Kenji Kikuchi, Tomofumi Haga, Keiko Numayama-Tsuruta, Hironori Ueno

The 26th Congress of the International Society of Biomechanics　2017
Response to the Letter to the Editor "Hemodynamics in the Microcirculation" by A. G. Koutsiaris

Toshihiro Omori, Yohsuke Imai, Kenji Kikuchi, Takuji Ishikawa, Takami Yamaguchi

ANNALS OF BIOMEDICAL ENGINEERING　44　(4)　1323-1323　2016/04

DOI： 10.1007/s10439-016-1570-1 　

ISSN： 0090-6964

eISSN： 1573-9686
Inhomogeneous distribution of Chlamydomonas in a cylindrical container with a bubble plume Peer-reviewed

Yuki Nonaka, Kenji Kikuchi, Keiko Numayama-Tsuruta, Azusa Kage, Hironori Ueno, Takuji Ishikawa

BIOLOGY OPEN　5　(2)　154-160　2016/02

DOI： 10.1242/bio.015669 　

ISSN： 2046-6390
Bio-Micropump by Using A Flagellate Propulsive Force of Escherichia coli Peer-reviewed

Kenji Kikuchi, Ryo Matsuura, Hironori Ueno, Yohsuke Imai, Noriaki Matsuki, Takami Yamaguchi, Takuji Ishikawa

The World Congress on Engineering 2016　ICSBB15　515-518　2016
Diffusive Promotion by Velocity Gradient of Cytoplasmic Streaming (CPS) in Nitella Internodal Cells Peer-reviewed

Kenji Kikuchi, Osamu Mochizuki

PLOS ONE　10　(12)　0144938-1-12　2015/12

DOI： 10.1371/journal.pone.0144938 　

ISSN： 1932-6203
Intergrated Computational Biomechanics of the Flow Phenomena in the Living Body

Takami Yamaguchi, Yosuke Imai, Toshihiro Omori, Kenji Kikuchi, Takuji Ishikawa

Computational Fluid Dynamics (CFD) in Medicine and Biology II　2015/09/01
Digest Blood Sucked by a Female Mosquito

Kenji Kikuchi, Yosuke Imai, Takami Yamaguchi, Takuji Ishikawa

The 8th Asian-Pacific Conference on Biomechanics　PS8-14　2015/09/01
Velocity profile of thin film flows measured using a confocal microscopy particle image velocimetry system with simultaneous multi depth position Peer-reviewed

K. Kikuchi, O. Mochizuki

MEASUREMENT SCIENCE AND TECHNOLOGY　26　(2)　025301-1-8　2015/02

DOI： 10.1088/0957-0233/26/2/025301 　

ISSN： 0957-0233

eISSN： 1361-6501
Hemodynamics in the Microcirculation and in Microfluidics

Toshihiro Omori, Yohsuke Imai, Kenji Kikuchi, Takuji Ishikawa, Takami Yamaguchi

ANNALS OF BIOMEDICAL ENGINEERING　43　(1)　238-257　2015/01

DOI： 10.1007/s10439-014-1180-8 　

ISSN： 0090-6964

eISSN： 1573-9686
Visualization of intestinal peristalsis of mosquito midgut by using micro x-ray imaging

Kenji Kikuchi, Yohsuke Imai, Takami Yamaguchi, Takuji Ishikawa

International Symposium on Integrated Nanobiomechanics　2015
Noninvasive Measurement of Drug Permeation in the Skin

Shunsuke Shigeta, Kenji Kikuchi, Keiko Numayama, Takuji Ishikawa

The 8th Asian-Pacific Conference on Biomechanics　2015
Effect of mucous viscosity on ciliary beat in the tracheal lumen

Tomofumi Haga, Kenji Kikuchi, Keiko Numayama-Tsuruta, Hironori Ueno, Takami Yamaguchi, Takuji Ishikawa

The 8th Asian-Pacific Conference on Biomechanics　2015
Measurement of Drug Permeation in the Skin by a Two Photon Microscopy

Shunsuke Shigeta, Kenji Kikuchi, Keiko Numayama, Takuji Ishikawa

The 22nd Congress of the European Society of Biomechanics　2015
Distrlibution of Microalgae Cells in a Tube Container with Aeration

Yuki Nonaka, Kenji Kikuchi, Keiko Numayama-Tsuruta, Azusa Kage, Hironori Ueno, Takuji Ishikawa

Internationnal Symposium on Integrated Nanobiomechanics　21-22　2014/07/05
Micro PIV measurement of slip flow on a hydrogel surface Peer-reviewed

K. Kikuchi, O. Mochizuki

MEASUREMENT SCIENCE AND TECHNOLOGY　25　(6)　065702-1-632　2014/06

DOI： 10.1088/0957-0233/25/6/065702 　

ISSN： 0957-0233

eISSN： 1361-6501
Morphological considerations of fish fin shape on thrust generation Peer-reviewed

K. Kikuchi, Y. Uehara, Y. Kubota, O. Mochizuki

Journal of Applied Fluid Mechanics　7　(4)　625-632　2014

DOI： 10.36884/jafm.7.04.21358 　

ISSN： 1735-3572

eISSN： 1735-3645
Some remarks on surface conditions of solid body plunging into water with particle method Peer-reviewed

Masao Yokoyama, Yoshihiro Kubota, Kenji Kikuchi, Genki Yagawa, Osamu Mochizuki

Advanced Modeling and Simulation in Engineering Science　1　(9)　1-14　2014
Effect of Rheological Properties on Cilliary Flow in the Airway

Yuki Nonaka, Kenji Kikuchi, Keiko Numayama-Tsuruta, Azusa Kage, Hironori Ueno, Takuji Ishikawa

International Symposium on Integrated Nanobiomechanics　23-24　2014
In Vivo Visualization of Cytoplasmic Streaming by Using Confocal Micro PTV Measurement

Kenji Kikuchi, Osamu Mochizuki

International Symposium on Integrated Nanobiomechanics　25-26　2014
Falling dynamics of immobilized Chlamydomonas reinhardtii

Azusa Kage, Kenji Kikuchi, Takuji Ishikawa

The Sixth International Symposium on Aero Aqua Bio-mechanisms2014　16-17　2014
Inhomogeneous distribution of cells in a microalgae suspension with aeration

Yuki Nonaka, Kenji Kikuchi, Keiko Numayama-Tsuruta, Azusa Kage, Hironori Ueno, Takuji Ishikawa

The Sixth International Symposium on Aero Aqua Bio-mechanisms2014　39-40　2014
Unsteady Drag Coefficient of a Falling Sphere in Water

KIKUCHI KENJI, KONNO TOMOHIRO, ICHIKAWA SEIJI, KUBOTA YOSHIHIRO, MOCHIZUKI OSAMU

日本機械学会論文集 B編(Web)　79　(798)　WEB ONLY 151-163-163　2013
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/kikaib.79.151 　

ISSN： 1884-8346

eISSN： 1884-8346

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The purpose of this study is to know differences between steady and unsteady drag coefficients of a sphere. Though we often have to estimate unsteady drag-forces acting on a moving obstacle, we are obliged to use the well-known steady drag coefficient for the first estimation because of lack of information about effects of unsteadiness on the drag coefficient. The usual way to take account of unsteadiness is an added mass. However, its application is restricted within the simple shape of an obstacle. We propose a way based on the equation of motion to obtain the unsteady drag coefficient. To confirm validity of the way, we measured and analyzed the motion of the falling sphere in water by using a high-speed camera and a motion capture method. The drag coefficients as a function of time were obtained by substituting measured values of velocity and acceleration into the equation of motion. The drag coefficient was 0.52 when the sphere attains the terminal velocity, being quite large at the beginning of motion. Comparing with the values obtained by the other previous studies, our result is reasonable.
Effects of slip condition on flow near the surface of hydro-gel

M. Yokoyama, Y. Kubota, K. Kikuchi, O. Mochizuki, G. Yagawa

Computational Methods for Coupled Problems in Science and Engineering V - A Conference Celebrating the 60th Birthday of Eugenio Onate, COUPLED PROBLEMS 2013　643-650　2013
Unsteady drag coefficient of a falling sphere in water Peer-reviewed

Kenji Kikuchi, Tomohiro Konno, Seiji Ichikawa, Yoshihiro Kubota, Osamu Mochizuki

Nihon Kikai Gakkai Ronbunshu, B Hen/Transactions of the Japan Society of Mechanical Engineers, Part B　79　(798)　151-163　2013

DOI： 10.1299/kikaib.79.151 　

ISSN： 0387-5016
物体壁面の表面性状を考慮した流れのシミュレーション Peer-reviewed

横山真男, 菊地謙次, 窪田佳寛, 望月修

ながれ；日本流体力学会誌　32　(4)　319-326　2013
Publisher:
ISSN： 0286-3154
Visualization of Cytoplasmic Streaming Peer-reviewed

Kenji Kikuchi, Narihisa Suzuki, Osamu Mochizuki

The 14th Asia Congress of Fluid Mechanics　16　(5)　1-4　2013
Near wall flow visualization by inclined-observation using confocal micro PIV method

K Kikuchi, O Mochizuki

The 12th International Symposium on Fluid Control, Measurement and Visualization　2013
Multi-modal pumping in drinking mosquitoes

K. Kikuchi, S. Chatterjee, W. -K Lee, M. A. Stremler, O. Mochizuki, J. J. Socha, U. Toyo

INTEGRATIVE AND COMPARATIVE BIOLOGY　52　E93-E93　2012/04

ISSN： 1540-7063
Fluid dynamics on fish’s tail fin

Kenji Kikuchi, Yusuke Uehara, Yoshihiro Kubota, Osamu Mochizuki

The 5th International Symposium on Aero Aqua Bio-Mechanisms　2012
Measurement of water-movement on a hydrogel

Kenji KIKUCHI, Osamu MOCHIZUKI

The 8th KSME-JSME Thermal and Fluids Engineering Conference　2012
Drag coefficient of an accelerated sphere

Kenji KIKUCHI, Tomohiro KONNO, Seiji ICHIKAWA, Yoshihiro KUBOTA, Osamu MOCHIZUKI

Joint international conference of ISEM-ACEM-SEM-7th ISEM12　2012
Micro-PIV (micro particle image velocimetry) visualization of red blood cells (RBCs) sucked by a female mosquito Invited Peer-reviewed

K. Kikuchi, O. Mochizuki

MEASUREMENT SCIENCE AND TECHNOLOGY　22　(6)　064002-1-9　2011/06

DOI： 10.1088/0957-0233/22/6/064002 　

ISSN： 0957-0233

eISSN： 1361-6501
Study of the pump of a mosquito Peer-reviewed

Kenji Kikuchi, Osamu Mochizuki

ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011　1　(D)　2001-2007　2011

DOI： 10.1115/AJK2011-19003 　
Thrust of a thin plate starting impulsively Peer-reviewed

Seiji Ichikawa, Kenji Kikuchi, Osamu Mochizuki

ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011　1　(D)　2857-2862　2011

DOI： 10.1115/AJK2011-16004 　
S0502-4-4 Wake of a suddenly accelerated plat

ICHIKAWA Seiji, KIKUCHI Kenji, MOCHIZUKI Osamu

The proceedings of the JSME annual meeting　2010　185-186　2010
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmemecjo.2010.2.0_185 　

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We studied on a vortex ring generated by a suddenly accelerated disk to understand a relation between the circulation and necessary force to accelerate the disk. To estimate a propulsive force of small swimming animals is our motivation. We measured velocity fields using a PIV system and high speed CMOS camera around a circular disk as a model of a fin and paddle. We showed that the time derivative of the circulation related to the force to drive the disk. Thus, the disk gives energy impulsively to the vortex ring. This gives us the way to estimate thrust if we could measure the change in circulation of the starting vortex ring by the disk. We applied it to the estimation of thrust by an accelerated non-circular disk by introducing an equivalent circle that has the same area as the non-circular disk.
J0205-4-3 Flow on a Hydrogel mimicked a surface of living cell

KIKUCHI Kenji, ICHIKAWA Seiji, MOCHIZUKI Osamu

The proceedings of the JSME annual meeting　2010　69-70　2010
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmemecjo.2010.6.0_69 　

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The purpose of our study is to know the interaction between a flow and a surface of hydro gel. Tissue of living organ like blood vessel, cartilage and eyeball is a hydro gel. It contains water, so that the surface of hydro gel is considered to be water. Thus, it is a hydrophilic material. We expect it to show good reduction of friction if we use it the wall of a conduit. To check the concept, we measured velocity profile of a film flow on the hydro gel by a micro PIV method, estimating wall share stress from the velocity gradient at the wall. We confirmed slip-velocity depending on degree of swelling of hydro gel and the flow inside of gel induced by shear stress.
アメンボはなぜ浮けるのか Peer-reviewed

望月修, 菊地謙次

可視化情報学会誌　30　(119)　232-237　2010

DOI： 10.3154/jvs.30.028 　
Consideration of thrust in escaping motion of a mosquito larva Peer-reviewed

Kenji Kikuchi, Osamu Mochizuki

Journal of Aero Aqua Bio-mechanism　1　(1)　111-116　2010
Publisher: Society of Aero Aqua Bio-mechanisms
DOI： 10.5226/jabmech.1.111 　

ISSN： 2185-1522

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Purpose of this study is to understand a thrust generation mechanism of a swimming mosquito larva. A quick escaping swimming behaved in their dangerous situations. A time-varying motion of a tail related a thrust was investigated by a motion capture method. Moreover, the velocity fields around the tail were measured by micro Particle Image Velocimetry (PIV) system. It was found that their unique wriggling motion generated the thrust in all sequence whereby an effective utilization of a vortex ring. The convenient way to estimate the thrust according to kinetic energy of the vortex ring was proposed in this paper.
A flow on a hydrogel surface mimicked a living cell

Kenji KIKUCHI, Osamu MOCHIZUKI

The 21st International Symposium on Transport Phenomena　2010
Visualization of RBC sucked by female mosquito

Kenji KIKUCHI, Osamu MOCHIZUKI

The 14th International Symposium on Flow Visualization　2010
J0202-2-5 Swimming of a wriggler

KIKUCHI Kenji, MOCHIZUKI Osamu

The proceedings of the JSME annual meeting　2009　145-146　2009
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmemecjo.2009.6.0_145 　

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The purpose of our study is to analyze swimming motion of a mosquito larva which is well called as a wriggler. When it meets some dangerous situations, it escapes actively from air-water surface to bottom with rapid swimming motion. A swimming thrust is obtained by a paddling motion of its tail fin with a separation of a vortex in the power stroke. We measured velocity vector fields around the body and wake by micro PIV measurements. It was found that a snapping motion of its tail fin yielded thrust.
Swimming motion of a mosquito larva

Kenji KIKUCHI, Osamu MOCHIZUKI

The 4th International Symposium on Aero Aqua Bio-Mechanisms　2009
蚊の吸血ポンプ特性評価 Peer-reviewed

菊地謙次, 寺田信幸, 望月修

生体医工学　46　(2)　232-237　2008

DOI： 10.11239/jsmbe.46.232 　
Micro-PIV Measurements in Micro-Tubes and Proboscis of Mosquito Peer-reviewed

Kenji KIKUCHI, Osamu MOCHIZUKI

Journal of Fluid Science and Technology　3　(8)　957-986　2008
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jfst.3.975 　

ISSN： 1880-5558

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Effects of the relative size of a particle to the diameter of a micro-tube on velocity profiles obtained by the micro-PIV measurement of the flow through the micro-tube were investigated to achieve the accuracy of measurements of the flow in a proboscis of a mosquito. The velocity profiles obtained for different diameter-ratios of a fluorescent particle and fused silica micro-tube were compared with the exact solution of the velocity profile of flow through a circular pipe at a low Reynolds number. A suitable diameter-ratio was found to be less than 0.04. The velocity profile of flow through the proboscis of a mosquito measured by using the suitable micro-PIV method satisfying the above condition was found to be different from the exact solution of the circular-pipe flow near the center of the proboscis. The velocity profile in the proboscis was similar to that of a rectangular cross section which was verified by a SEM observation.
Inside Flow of Mosquito's Proboscis

Kenji Kikuchi, Osamu Mochizuki

DFD06 Meeting of The American Physical Society　2006
Pump system of Mosquito

Kenji KIKUCHI, Nobuyuki TERADA, Osamu MOCHIZUKI

The 3rd International Symposium on Aero Aqua Bio-Mechanisms　2006
Mosquito’s sucking mechanism

Kenji Kikuchi, Osamu Mochizuki

DFD05 Meeting of The American Physical Society　2005
Mosquito’s Sucking Blood Mechanism

Kenji KIKUCHI, Osamu MOCHIZUKI

The 4th KSME-JSME Thermal and Fluids Engineering Conference　24　(1)　133-134　2005
Publisher: The Visualization Society of Japan
DOI： 10.3154/jvs.24.Supplement1_133 　

ISSN： 0916-4731

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The purpose of our study is to apply Mosquito's sucking blood mechanism to a pump of μ-TAS for checking blood. We want to know how high the power of Mosquitos pump is have. This paper presents a structure of Mosquitos bio-pump, and its characteristics as mechanical pump. We made the mosquito feed blood of an arm. Pictures are taken by SEM, and many slices of a mosquito with 2μm thickness after fixed by wax were made. We anatomized the mosquito's head and picked up the bio-pump under the microscope. The mosquitos bio-pump is found to be enough power to apply a pump of μ-TAS.
Mosquito's proboscis Peer-reviewed

K Kikuchi, O Mochizuki

JOURNAL OF VISUALIZATION　8　(1)　7-7　2005

DOI： 10.1007/BF03181596 　

ISSN： 1343-8875
Performance of mosquito’s pump

Kenji Kikuchi, Osamu Mochizuki

DFD04 Meeting of The American Physical Society　2004

Show all ︎Show first 5

Misc. 54

歯科治療における飛沫エアロゾルの可視化 Invited

渡辺隼, 菊地謙次, 小林洋子, 矢代航, 金髙弘恭, 江草宏

光アライアンス　34　(8)　35-39　2023/08
歯科治療で発生するエアロゾル挙動の可視化

小林洋子, 渡辺隼, 梶田倫功, 山内健介, 金高弘恭, 江草宏, 五十嵐薫, 矢代航, 菊地謙次, 西村秀一, 森島浩允, 佐藤舜, 菅井優生

東北大学歯学雑誌　39/40/41　(2/1-2/1)　49-49　2022/06
Publisher: 東北大学歯学会
ISSN： 0287-3915
ジオラマ環境における酵母発酵流れの力学的理解～微生物由来ブラジルナッツ効果の発見～ Invited

菊地謙次, 石川拓司

アグリバイオ　50　1154-1158　2021/11
工学的アプローチによるモデル生物の流動の医学・生物学的理解

菊地謙次, 石川拓司

細胞　53　(13)　858-863　2021/11
Publisher: (株)ニュー・サイエンス社
ISSN： 1346-7557
知って得する最新情報マスクや衣服の擦れによる皮膚の脆弱化皮膚のバイオメカニクスと摩擦刺激によるひずみの積み残し

菊地謙次

皮膚病診療　43　(3)　268-269　2021/03
Publisher: (株)協和企画
ISSN： 0387-7531
知って得する最新情報マスクや衣服の擦れによる皮膚の脆弱化摩擦刺激と角化細胞の塑性変形

菊地謙次

皮膚病診療　43　(2)　172-173　2021/02
Publisher: (株)協和企画
ISSN： 0387-7531
Drug Permeation Measurement through the Skin by using a Two-Photon Laser Induced Fluorescent Microscopy Peer-reviewed

Kenji Kikuchi, Shunsuke Shigeta, Keiko Tsuruta-Numayama, Takuji Ishikawa

8th International Conference on Fluid Mechanics (ICFM8)　S10BM0-04　2018/09
Behavior of motile unicellular alga flowing in a microchannel Peer-reviewed

Cheng-Hsi Chuang, Kenji Kikuchi, Azusa Kage, Takuji Ishikawa

8th International Conference on Fluid Mechanics (ICFM8)　S10BM0-01　2018/09
Gut Bacterial Flow in Zebrafish Larva

Masahiro Takahashi, Kenji Kikuchi, Keiko Numayama-Tsuruta, Takuji Ishikawa

26　2018/08
FILTRATION FLOW BY CHOANOFLAGELLATE CHAMBERS OF FRESH-WATER SPONGES

K. Kikuchi, H. Maleprade, R. E. Goldstein, T. Ishikawa

18th International Symposium on Flow Visualization　11.1.1　2018/06
197 Measurement of the behavior of cancer cells cultivated on a collagen gel

Iwasaki Yuwa, Imai Yohsuke, Kikuchi Kenji, Numayama-Tsuruta Keiko, Shigeta Shunsuke, Ishikawa Takuji

The Proceedings of Conference of Tohoku Branch　2016　(0)　191-192　2016
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmeth.2016.51.191 　
201 Real Time Visualization of Intestinal Peristalsis of the Zebrafish

NOH Hyeongtak, KIKUCHI Kenji, NUMAYAMA Keiko, ISHIKAWA Takuji

The Proceedings of Conference of Tohoku Branch　2016　(0)　199-200　2016
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmeth.2016.51.199 　
PS8-13 Effect of mucous viscosity on ciliary beat in the tracheal lumen(PS8: Poster Short Presentation VIII,Poster Session)

Haga Tomofumi, Kikuchi Kenji, Numayama-Tsuruta Keiko, Ueno Hironori, Yamaguchi Takami, Ishikawa Takuji

Proceedings of the ... Asian Pacific Conference on Biomechanics : emerging science and technology in biomechanics　2015　(8)　364-364　2015/09/16
Publisher: The Japan Society of Mechanical Engineers
PS8-14 Visualization of intestinal peristalsis of mosquito midgut by using micro X-ray imaging(PS8: Poster Short Presentation VIII,Poster Session)

Kikuchi Kenji, Imai Yohsuke, Numayama-Tsuruta Keiko, Yamaguchi Takami, Ishikawa Takuji

Proceedings of the ... Asian Pacific Conference on Biomechanics : emerging science and technology in biomechanics　2015　(8)　365-365　2015/09/16
Publisher: The Japan Society of Mechanical Engineers
PS1-9 Noninvasive Measurement of Drug Permeation in the Skin(PS1: Poster Short Presentation I,Poster Session)

Shigeta Shunsuke, Kikuchi Kenji, Numayama Keiko, Ishikawa Takuji

Proceedings of the ... Asian Pacific Conference on Biomechanics : emerging science and technology in biomechanics　2015　(8)　230-230　2015/09/16
Publisher: The Japan Society of Mechanical Engineers
W052002 Low RBC interference in micro channel learned by mosquito blood sucking mechanism

KIKUCHI Kenji

Mechanical Engineering Congress, Japan　2015　"W052002-1"-"W052002-2"　2015/09/13
Publisher: The Japan Society of Mechanical Engineers

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We have been focusing on a possibility of low interference within blood flow in a micro scale channel. The RBC is at once taken heavy shear stress from velocity fields, the hemolysis, which put inside hemoglobin out, occurs. In that case, the RBC is broken by shear stress and makes to change to ghost RBC. Such blood isn't suitable for blood checking of healthcare hence we have to suck blood under pressure loss restriction. The final goal of this research is an inspired design for micro needle learned by mosquito blood sucking mechanism. We perform that a consideration of low RBC interference in micro channel learned by mosquito blood sucking mechanism by an analytical method of basic fluid mechanics.
クラミドモナスの鞭毛は上向きトルク発生に寄与する Invited

鹿毛あずさ, 菊地謙次, 石川拓司

京都大学数理解析研究所講究録　1940　110-111　2015/04
Publisher: 京都大学
ISSN： 1880-2818
2B35 Effect of aeration on the distribution of Chlamydomonas

NONAKA Yuki, KIKUCHI Kenji, NUMAYAMA-TSURUTA Keiko, KAGE Azusa, UENO Hironori, ISHIKAWA Takuji

The Proceedings of the Bioengineering Conference Annual Meeting of BED/JSME　2015　(0)　371-372　2015
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmebio.2015.27.371 　
2B41 Effect of Rheological Properties on Ciliary motion and Flow in the airway

HAGA Tomofumi, KIKUCHI Kenji, UENO Hironori, NUMAYAMA Keiko, YAMAGUCHI Takami, ISHIKAWA Takuji

The Proceedings of the Bioengineering Conference Annual Meeting of BED/JSME　2015　(0)　373-374　2015
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmebio.2015.27.373 　
1316 Flow on a ciliary respiratory epithelium

HAGA Tomofumi, KIKUCHI Kenji, UENO Hironori, NUMAYAMA Keiko, YAMAGUCHI Takami, ISHIKAWA Takuji

The Proceedings of the Fluids engineering conference　2015　(0)　_1316-1_-_1316-2_　2015
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmefed.2015._1316-1_ 　

ISSN： 1348-0251

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We have studied experimentally about the flow on a ciliary respiratory epithelium with the relation between a viscosity of mucus and a generated flow velocity using μPTV measurement. We used a fresh dissected mouse respiratory epithelium for our experiment, and observed a flow on it by using a confocal microscopy for tracing micro fluorescent particles, which dispersed in the mucus on the ciliary cells. The frequency of ciliary motions and velocity of mucus were measured in several cases with different viscosity of mucus. The driven force for generating ciliary flow has a non-linearity with an increasing of viscosity. Our findings would play a medical role to clarify a mechanism of mucus flow on a ciliary respiratory epithelium with its viscous changing.
J0260202 Dispersion of red blood cells in a micro channel

CHENG-HSI Chuang, KIKUCHI Kenji, NUMAYAMA Keiko, YAMAGUCHI Takami, ISHIKAWA Takuji

The Proceedings of Mechanical Engineering Congress, Japan　2015　(0)　_J0260202--_J0260202-　2015
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmemecj.2015._J0260202- 　

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We have been focused on the dispersion of cells in micro channel flow, especially red blood cells (RBCs). When RBCs are dispersed in a micro channel with a Y-shape junction, the dispersion of cells would occur from denser to thinner direction according with concentration of cells. It is regarding to clarify the dispersion phenomena in micro channel for designing of lab-on-a-chip applications. The detailed mechanism of cell dispersion, however, has not been fully clarified yet. We performed the quantitative dispersion measurement in the Y-shape micro channel, in which two layers with and without RBCs flow in parallel, and investigated the effects of flow rates and hematocrit. Our results suggest that the dispersion in micro channel would be more dominant than Brownian diffusion, and depends on the hematocrit and the flow rate. These findings provide us useful information on mass transport in cell suspensions.
A104 Behavior of Yorticella in shear flow

YOSHIDA Naoto, KIKUCHI Kenji, KAGE Azusa, NUMAYAMA Keiko, NAGAI Moeto, ISHIKAWA Takuji

The Proceedings of the JSME Conference on Frontiers in Bioengineering　2015　(0)　7-8　2015
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmebiofro.2015.26.7 　

ISSN： 1348-2939
A108 Drug concentration measurement in a skin using two-photon microscopy

SHIGETA Shunsuke, KIKUCHI Kenji, NUMAYAMA Keiko, ISHIKAWA Takuji

The Proceedings of the JSME Conference on Frontiers in Bioengineering　2015　(0)　15-16　2015
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmebiofro.2015.26.15 　

ISSN： 1348-2939
S0510103 Flow around Tail Fin

UEHARA Yusuke, KIKUCHI Kenji, KUBOTA Yoshihiro, MOCHIZUKI Osamu

Mechanical Engineering Congress, Japan　2014　(0)　"S0510103-1"-"S0510103-4"　2014/09/07
Publisher: 一般社団法人日本機械学会

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There are various shapes in the tail fin of fish in nature. The way to use of tail fin should differ by shapes. In this study, we aimed to determine the relationship between thrust generation and fish fin shape. To compare the effect of fin shape had on thrust generation, we categorized the morphological shapes of fish fins into equilateral polygonal shapes. Polygonal fins were used to generate thrust that depended only on shape. These fins were constructed of a hard elastic material to eliminate any influence of shape deformation. A servomotor with a reciprocal rotation moved a fin cyclically, and thrust was experimentally measured using a strain gage system. We experimented in static fluid and uniform flow. In static fluid, thrust tended to be proportional to the inertia moment of a fin, which indicated difficulty with rotation. Moreover, this trend for thrust generation was directly related to the length of the perimeter of a polygonal fin. In uniform flow, thrust is reduced relative to the static fluid. Highest thrust was generated by the diamond shape.
尾ひれまわりの流れ

上原裕介, 菊地謙次, 窪田佳寛, 望月修

日本機械学会年次大会講演論文集(CD-ROM)　2014　ROMBUNNO.S0510103　2014/09/06

ISSN： 2424-2667
Meandering of permeation flow

豊田睦, 菊地謙次, 窪田佳寛, 望月修

可視化情報学会誌　34　(Suppl.1)　163‐164　2014/07/01

ISSN： 0916-4731
2G35 Water flow in leaf vein

KIKUCHI Kenji, SATO Keita, MOCHIZUKI Osamu

2014　(26)　541-542　2014/01/10
Publisher: The Japan Society of Mechanical Engineers
J0220101 Effect of aeration on the distribution of micro algae cells

NONAKA Yuki, UENO Hironori, NUMAYAMA-TSURUTA Keiko, KIKUCHI Kenji, ISHIKAWA Takuji

The Proceedings of Mechanical Engineering Congress, Japan　2014　(0)　_J0220101--_J0220101-　2014
Publisher: The Japan Society of Mechanical Engineers
DOI： 10.1299/jsmemecj.2014._J0220101- 　

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When culturing microalgae, we often use aeration for mixing the culture fluid. However, it is not clear how microalgae and aeration interact each other. In order to understand transport phenomena in a microalgae suspension, it is important to clarify the distribution of cells in a container. In this study, we visualized the distribution of microalgae in a tube container with aeration. In the case without aeration, we observed the bioconvection with chaotic pattern. In the case with aeration, on the other hand, we observed cells aggregated in specific regions.
J027024 Flow on Leaf Vein

SATO Keita, KIKUCHI Kenji, MOCHIZUKI Osamu

Mechanical Engineering Congress, Japan　2013　"J027024-1"-"J027024-2"　2013/09/08
Publisher: The Japan Society of Mechanical Engineers

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The Leaf has a complex network as leaf vein. The leaf vein supply water efficiently to the whole of own. If there is some worm hole on its leaf by bug biting, the water in leaf vein flows continuously. This network system might be applied bio-mimically for an electrical and water infrastructure in near future. We observed the flow patterns of water in the Nandina domestica's Leaf vein with three patterns of normal leaf, damaged leaf and only leaf vein. The flow in leaf vein ware visualized by fluorescent solution by own water suction of leaf. As a result, the most of sucked water was flowed in the main leaf vein in each leaves, then the flows were spread into the lateral veins gradually. In the case of damaged leaf, the flow in the main leaf vein stopped at the worm hole, the water was bypassing the hole through the other fine veins. We found that leaf veins supply the water to whole of leaf even if leaf has damage in leaf vein according as a capillary phenomenon.
魚の尾鰭形状と推進力に関する研究

上原裕介, 菊地謙次, 窪田佳寛, 望月修

バイオエンジニアリング講演会講演論文集　25th　(25)　123-124　2013/01/08
Publisher: The Japan Society of Mechanical Engineers
ISSN： 1348-2920
0701 Water splash formed by a frog diving into water

Kubota Yoshihiro, Kikuchi Kenji, Mochizuki Osamu

Fluids engineering conference ...　2012　(0)　277-278　2012/11/16
Publisher: 一般社団法人日本機械学会
ISSN： 1348-0251

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The objective of this study is to understand the formation of water splash by the frog diving into water.Splash formation by the frog diving was investigated by using high speed camera.The characteristics of frog diving were studied with model experiments.The model experiments obtained the influence of both body shape and hydrophihcity as surface condition.Body shape was investigated with the influence of tail shape of body and NACA 0012 airfoil in cross-section.Frog diving caused the small water splash formation with air cavity under the water.The formation of splash was related to the film-flow caused by body impacted to water surface.The fore limb of frog set along the body during the dive.This is the reason to inhibit the formation of separation of film-flow.The strong hydrophihc body of frog was caused film separation.
Gliding characteristics of a butterfly

北島綾香, 窪田佳寛, 菊地謙次, 望月修

可視化情報学会誌　32　(Suppl.2)　125‐126　2012/09/15

ISSN： 0916-4731
Numerical simulation of flow near the boundary of hydrogel

横山真男, 菊地謙次, 窪田佳寛, 望月修

可視化情報学会誌　32　(Suppl.2)　133‐134　2012/09/15

ISSN： 0916-4731
加速する三次元物体の抵抗係数

今野友博, 菊地謙次, 市川誠司, 窪田佳寛, 望月修

日本機械学会年次大会講演論文集(CD-ROM)　2012　ROMBUNNO.S053046　2012/09/08

ISSN： 2424-2667
魚の尾鰭形状と推進力に関する研究

工藤裕司, 菊地謙次, 窪田佳寛, 望月修

バイオエンジニアリング講演会講演論文集　24th (CD-ROM)　(24)　ROMBUNNO.8G36-1"-"8G36-2"　2012/01/06
Publisher: The Japan Society of Mechanical Engineers
ISSN： 1348-2920
直列円錐群まわりの流れの可視化

四元大, 菊地謙次, 窪田佳寛, 望月修

バイオエンジニアリング講演会講演論文集　24th (CD-ROM)　(24)　ROMBUNNO.8G37-1"-"8G37-2"　2012/01/06
Publisher: The Japan Society of Mechanical Engineers
ISSN： 1348-2920
蛙の跳び込みに伴うスプラッシュの形成

窪田佳寛, 菊地謙次, 望月修

日本機械学会流体工学部門講演会講演論文集(CD-ROM)　90th　ROMBUNNO.0701　2012

ISSN： 1348-2882
Report of the 39th Visualization Symposium of Japan

KIKUCHI Kenji

31　(123)　163-163　2011/10/01

ISSN： 0916-4731
Process of equivalent of two liquids with different concentration

TOYODA MUTSUMI, KIKUCHI KENJI, KUBOTA YOSHIHIRO, MOCHIZUKI OSAMU

可視化情報学会誌　31　(Suppl.2)　103-104　2011/09/13

ISSN： 0916-4731
Visualization of frog's behavior

TAGUCHI AYANO, KUBOTA YOSHIHIRO, KIKUCHI KENJI, MOCHIZUKI OSAMU

可視化情報学会誌　31　(Suppl.2)　101-102　2011/09/13

ISSN： 0916-4731
加速する三次元物体の抵抗係数

菊地謙次, 今野友博, 市川誠司, 窪田佳寛, 望月修

日本機械学会年次大会講演論文集　2011 (CD-ROM)　ROMBUNNO.S054021　2011/09/10

ISSN： 2424-2667
1106 Flow near bio-material surface

INABA Toshihiko, ICHIKAWA Seiji, KIKUCHI Kenji, MOCHIZUKI Osamu

Fluids engineering conference ...　2010　317-318　2010/10/29
Publisher: The Japan Society of Mechanical Engineers
ISSN： 1348-2882

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It aims to establish a method of measuring friction drag of bio-material under unsteady moving condition by using a motion capture system. The model covered with several materials was fallen in a water tank by gravity, and measured each speed by using a high speed video camera. We carried out the estimation of friction drag of the bio-material surface by an unsteady motion equation. In this study, the materials we evaluated were a hydrophobic cloth, artificial skins and a sea snake skin. As a result, the hairless artificial skin showed the smallest drag-coefficient and the hydrophobic cloth the largest.
1105 Protoplasmic streaming of plant cell

SUMIDA Yosuke, ICHIKAWA Seiji, KIKUCHI Kenji, MOCHIZUKI Osamu

Fluids engineering conference ...　2010　315-316　2010/10/29
Publisher: The Japan Society of Mechanical Engineers
ISSN： 1348-2882

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Protoplasmic streaming is a phenomenon of particle movement in living cell. The particles were contained the cellular organelles and other particles called mitochondria and chloroplasts. We want to know the role of protoplasmic streaming in living plant cell. In this study we observed two types of protoplasmic streaming of Nitella and Tradescantia. The vesicle of moving speed and size were measured by microscopic observation. The cell division time was estimated from the volume of vesicle and cell, the moving speed and distribution of vesicles. As a result, the tradescantia cell division time was about 3.47×10^<17> hours. It was found that the protoplasmic streaming of Tradescantia was contributed 1.64×10^<-15>% for cell volume expansion
1129 Vorex observed in swimming of a small animal

ICHIKAWA Seiji, KIKUCHI Kenji, MOCHIZUKI Osamu

2009　(22)　387-387　2010/01/08
Publisher: The Japan Society of Mechanical Engineers
Flow near surface on frog skin

Kikuchi Kenji, Inaba Toshihiko, Ichikawa Seiji, Mochizuki Osamu

2010　232-232　2010
Publisher: 日本流体力学会

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A detail measurement of velocity gradient on wall surface is to better understand a friction drag against wall. We carried out the visualization of flow near the wall surface by confocal micro PIV system. In generally known, a surface of a living tissue has reduction of friction drag because of a tissue consisted of a hydro-gel. To know the effect of friction drag by surface materials, we developed the confocal micro PIV system for measurement of velocity gradient near the surface. It was found that the velocity profile of dropped flow on glass surface was similar to that of open channel flow. This system is suitable for measurement of friction drag effected on wall with free surface flow.
1608 Flow around a mosquito larva

KIKUCHI Kenji, MOCHIZUKI Osamu

Fluids engineering conference ...　2009　497-498　2009/11/06
Publisher: The Japan Society of Mechanical Engineers
ISSN： 1348-2882

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The purpose of our study is to analyze swimming motion of a mosquito larva. When it meets some dangerous situations, it escapes actively from air-water surface to bottom with rapid swimming motion and some time later it is back to water surface for its breathing. A swimming thrust is obtained by a paddling motion of its tail fin with a separation of a vortex in the power stroke. We measured velocity vector fields around the body and wake by micro PIV measurements. It was found that a snapping motion of its tail fin yielded thrust.
Retaining water by flat soil model

HASEGAWA Machiko, KIKUCHI Kenji, MOCHIZUKI Osamu

29　(2)　259-260　2009/10/15

ISSN： 0916-4731
Velocity Measurement of Flow in Mosquito proboscis

KIKUCHI Kenji, MOCHIZUKI Osamu

29　(2)　239-240　2009/10/15

ISSN： 0916-4731
Flow in an oil film on water in a vibrating small container

UYAMA Ryoichi, YOKOYAMA Masao, KIKUCHI Kenji, MOCHIZUKI Osamu

29　(2)　199-200　2009/10/15

ISSN： 0916-4731
M4-4 Design of a Micro Rotary Pump Worked by a Rotational Magnetic Field (M4 Pump and Droplet/Bubble Manipulation)

KIKUCHI Kenji, MOCHIZUKI Osamu

2009　(1)　77-78　2009/10/15
Publisher: The Japan Society of Mechanical Engineers

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A micro pump has not been developed for a micro TAS to transport blood because of size effects. We have developed a micro rotary pump worked by a rotary magnetic field. The rotor was designed by morphology based on mimetics of a shape of mosquito's sucking blood pump system with high performance. This pump consists of a rotor implanted magnets, a square-shaped casing and four input-output ports. We measured pressure and flow rate of the scale-up model of the micro rotary pump and compared them with numerically estimated values.
Flow on a Hydrogel mimicked a surface of living skin

KIKUCHI Kenji, ICHIKAWA Seiji, MOCHIZUKI Osamu

2009　356-356　2009
Publisher: 日本流体力学会

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The purpose of our study is to know the interaction between a flow and a surface of hydro gel. Tissue of living organ like blood vessel, cartilage and eyeball is a hydro gel. It contains water, so that the surface of hydro gel is considered to be water. Thus, it is a hydrophilic material. We expect it to show good reduction of friction if we use it the wall of a conduit. To check the concept, we measured velocity profile of a film flow on the hydro gel by a micro PIV method, estimating wall share stress from the velocity gradient at the wall. We confirmed slip-velocity depending on degree of swelling of hydro gel.
X-ray visualization of a mosquito's head

KIKUCHI Kenji, MOCHIZUKI Osamu

28　(1)　329-330　2008/07/01

ISSN： 0916-4731
AM06-28-001 Flow in Mosquito's Proboscis

KIKUCHI Kenji, Terada Nobuyuki, Mochizuki Osamu

2006　376-376　2006
Publisher: 日本流体力学会

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The purpose of our study is to apply mosquito's pump system to μ-TAS. To drive the μ-TAS, it is important to know necessary power of the pump. The mosquito's pump has surely excellent mechanism that we never know by our previous estimation. We focused on how high the power of mosquito's pump is and how small the resistance in a proboscis is. To know the sucking mechanism of mosquito, we measured the Blood flow by Mosquito's sucking by using micro-PIV measurements directly. Furthermore, to know the precise velocity distribution in Mosquito's proboscis, we used a confocal micro-PIV system. As result, we could obtain that there are a possibility of drag reductive effect at the interactions between flow and wall. In this paper, we suggested that Mosquito's pump system has the possibilities to apply a μ-TAS devise by the microscopic observation of a micro flow.
Essays on the 32^<nd> Symposium on Visualization

KIKUCHI Kenji

24　(95)　260-260　2004/10/01

ISSN： 0916-4731

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Books and Other Publications 2

UP, Number626

東京大学出版会　2024/12
Integrated Nano-Biomechanics 1st Edition

KIKUCHI Kenji

Elsevier　2018/01

Presentations 23

流れ知り、生き物を知る～微生物からヒトにおける生物流体力学～ Invited

菊地謙次

第36回生命科学交流ミーティング　2023/02
Macro biological transports induced by micro-scale gas generation by fermenting yeast cells Invited

Kikuchi Kenji

33rd 2022 International Symposium on Micro-NanoMechatronics and Human Science　2022/11
生体流動のライブイメージングとバイオメカニクス～微生物からヒトにおける生物流体力学～ Invited

菊地謙次

浅虫教育研究センター令和4年度公開臨海実習（Ａコース）異分野融合特別講義　2022/08
Microbial mixing and transport by yeast fermeting yeast

Kenji Kikuchi, Atul Srivastava, Takuji Ishikawa

Biological Fluids & Flows: A Conference to celebrate the 80th Birthday of Prof. Tim Pedley FRS　2022/03/31
皮膚伸展刺激による経皮吸収促進効果と薬剤表面特性の関係性

安田廉平, 石川拓司, 菊地謙次

2022/01/13
経皮的インターベンションにおける穿刺抵抗力低減を目指した振動針の開発

杉山航二郎, 菊地謙次, 高瀬圭, 石川拓司

第32回バイオフロンティア講演会, 講演論文集医療機器・診断・治療4 2D28 (2022)　2022/01/13
Instantaneous puncture for accurate needle insertion in percutaneous intervention

Kojiro Sugiyama, Kenji Kikuchi, Tomomi Sato, Sota Oguro, Satoru Yanagaki, Kei Takase, Takui Ishikawa

The 11th Asian-Pacific Conference on Biomechanics　2021/12/03
病原菌・ウイルスが皮膚を介して感染するリスクに警鐘

菊地謙次

ＣＳＪ化学フェスタ「コロナに負けるな！衛生分野からの挑戦」　2021/10
なぜ上面発酵ビール酵母は培養液中に浮遊できるのか？ Invited

菊地謙次

日本機械学会第33回バイオエンジニアリング部門講演会　2021/06
繊毛・鞭毛運動が織りなす生物流動，計測自動制御学会分子ロボティクス研究会 Invited

菊地謙次

計測自動制御学会分子ロボティクス研究会　2020/10
バイオイメージングが拓く生物流体工学 Invited

菊地謙次

日本機械学会東北支部第５６期秋季講演会　2020/09
ゼブラフィッシュ稚魚を用いた腸蠕動による撹拌と輸送 Invited

菊地謙次

せん断流の多様な機能の探究と先端科学技術への応用に関する研究分科会　2020/07
生物流体から学ぶバイオミメティクス Invited

菊地謙次

2019 年度高分子・ハイブリッド材料研究センター（PHyM）若手フォーラム　2019/11/13
Phase contrast x-ray imaging in bio-mechanical aspects; mosquito bloody ingestion International-presentation Invited

Kenji Kikuchi

Next Generation Synchrotron Radiation Workshop　2019/08/18
蚊の吸血ポンプの隠されたロバスト性 Invited

菊地謙次

2018年度研究集会「生物流体力学の展望」　2018/11/12
生体流動の可視化と生体ポンプの特性評価 Invited

菊地謙次

第38回エアロ・アクアバイオメカニズム学会　2018/03/20
生物における流れの可視化とバイオイメージング Invited

菊地謙次

フロンティアバイオイメージング研究会　2017/11/07
Visualization of Biological flow in small nature International-presentation Invited

Kenji Kikuchi

Fluid & Aerodynamics Research Group Seminar Series　2017/03/01
生物における流れと運動 Invited

菊地謙次

自動車技術会流体技術部門委員会　2016/02/12
蚊の吸血に学ぶ血球との干渉低減について Invited

菊地謙次

日本機械学会年次大会ワークショップ「血流を視る研究会」　2015/09/16
自然界の忍者！血を吸う蚊のひみつ Invited

菊地謙次

第２１回流れのふしぎ展　2015/08/11
生物流れの可視化で未来を切り拓く！?バイオミメティクスとシンバイオシスへの展望? Invited

菊地謙次

可視化情報シンポジウム　2015/07/21
蚊の吸血機能の解明と可視化 Invited

菊地謙次

日本混相流学会・日本実験力学会合同研究会　2012/08/08

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Industrial Property Rights 5

鮮度計測装置及び鮮度計測方法

菊地謙次, 望月修, 東洋, 杉田杏奈

特許第6463906号

Property Type: Patent
解凍装置及び品質維持装置

加藤正平, 菊地謙次, 畠一嘉(ヒガノ株式会社, 大川令, 東洋

Property Type: Patent
Vibrating needle deveice and needle insertion method

Kenji Kikuchi, Kojiro Sugiyama, Takuji Ishikawa, Kei Takase

Property Type: Patent
振動針装置及び針の挿入方法 (PCT国際出願)

菊地謙次, 杉山航二郎, 石川拓司, 高瀬圭

Property Type: Patent
流体抵抗計測方法及びその装置

鳴尾丈司, 津濃株式会社主任研究員, 荻野毅(美津濃株式会社主任研究員, 田中啓介, 濃株式会社主任研究員, 松崎健(美津濃株式会社アパレル開発生産部, 菊地謙次, 望月修, 東洋

特許第5841631号

Property Type: Patent

Research Projects 15

Mechanisms of Long-Distance Migration in Migratory Fish Species

Offer Organization: Japan Society for the Promotion of Science

System: Grants-in-Aid for Scientific Research

Category: Grant-in-Aid for Scientific Research (B)

Institution: Hokkaido University

2025/04/01 - 2029/03/31
Development of non-invasive imaging methods of Biological flow and concentration field for in vivo physiological immune system interference

Offer Organization: Japan Society for the Promotion of Science

System: Grants-in-Aid for Scientific Research

Category: Grant-in-Aid for Scientific Research (B)

Institution: Tohoku University

2022/04/01 - 2026/03/31
ジオラマ環境で覚醒する原生知能を定式化する細胞行動力学

Offer Organization: 日本学術振興会

System: 学術変革領域研究(A)（総括班）

Institution: 東北大学

2021/10 - 2026/03
生物系アクティブマターの予測と制御を目指した移動現象論の構築

Offer Organization: 日本学術振興会

System: 基盤研究（S）

Institution: 東北大学

2021/10 - 2026/03
ジオラマ環境における濃密微生物のin vivo4D-X線トモグラフィー法の開発

Offer Organization: 日本学術振興会

System: 学術変革領域研究（A）

Institution: 東北大学

2021/10 - 2026/03
薬剤輸送を目指した柔らかいマイクロスイマーの開発

石川拓司, 菊地謙次, ニックスステファニー, 大森俊宏

Offer Organization: 日本学術振興会

System: 科学研究費助成事業

Category: 国際共同研究加速基金(国際共同研究強化(B))

Institution: 東北大学

2021/10/07 - 2025/03/31
生物流体と生命現象のクロストークダイナミクスの創成

Offer Organization: 科学技術振興機構

System: 創発的研究推進事業

Institution: 東北大学

2021/04 - 2024/03
振動穿刺システムによるIVRアブレーション治療の精度向上に関する研究

Offer Organization: 日本医療研究開発機構

System: 橋渡し研究戦略的推進プログラム医工連携拠点の支援を活用した異分野融合型研究開発の最適化

Institution: 東北大学

2021/04 - 2023/03
Upgrading Microbial Biomechanics

Ishikawa Takuji

Offer Organization: Japan Society for the Promotion of Science

System: Grants-in-Aid for Scientific Research

Category: Grant-in-Aid for Scientific Research (A)

Institution: Tohoku University

2017/04/01 - 2021/03/31

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By using an original method that carefully builds up physical laws from the nanoscale to the macroscale, we have clarified the behavior and biological functions of sperm, microalgae, ciliates, E. coli, yeast, and other organisms under mechanical environments. We succeeded in analyzing through the scale hierarchy from the movement of ciliary axonemes driven by molecular motors, synchronization of flagellar movement, swimming and biological responses of ciliates with many flagella, two-body interactions and cooperative swimming, rheology and diffusion properties as a continuum, cell growth and accumulation, and so on. These results were published in a total of 48 peer-reviewed journal articles, including two in PNAS, one in Science Adv, and six in J Fluid Mech. In addition, 8 press releases were issued to widely publicize the research results.
Development of in vivo measurement of drug permeation and enhancement of transdermal drug delivery

Kikuchi Kenji

Offer Organization: Japan Society for the Promotion of Science

System: Grants-in-Aid for Scientific Research Grant-in-Aid for Challenging Exploratory Research

Category: Grant-in-Aid for Challenging Exploratory Research

Institution: Tohoku University

2016/04/01 - 2018/03/31

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To control a drug permeation from the skin surface, a three dimensional skin structure and precise drug permeation measurements are needed. We measured non-invasively the three dimensional skin structure by using a two photon microscopy and the drug permeation through the skin surface by using a confocal microscopy. As our results, the qualitative measurements of the strain of skin surface and the amount of permeated drug through the skin were succeeded. We found the mechanism of drug permeation through the skin surface with the skin extension.
in vivo経皮吸収計測法の開発と塗込による浸透促進効果の解明 Competitive

菊地謙次

Offer Organization: 日本学術振興会

System: (挑戦的)萌芽研究

2016/04 - 2017/03

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経皮吸収薬の薬剤浸透量を能動的に制御するには，皮膚内部の三次元構造と薬剤物性および塗込せん断速度と薬液浸透量の関係を結びつける定量的解析が必要不可欠である．本研究では，経皮吸収薬の浸透を表皮における塗込動作による能動的制御を目的とし，二光子顕微鏡を用いた革新的な非侵襲皮膚三次元構造の計測と，共焦点顕微鏡を駆使した独創的な薬剤せん断速度計測および浸透量計測を行い経皮吸収量の能動的制御法の開発を目的としている．本年度は，１）二光子顕微鏡を用いて，in vivoにおけるブタ皮膚の三次元組織構造の計測手法の構築を行なった．生体毒性がほとんどない蛍光分子ウラニンを薬剤モデルとし，薬剤モデルが皮膚内部根浸透した後に，二光子顕微鏡で皮膚内部を観察することで薬剤浸透経路の観察に成功した．また，皮膚表面の角質層をローダミンBにより可視化することで，薬剤と皮膚との境界となるミクロスケールの構造の計測に成功した．また，選択的組織染色により皮膚内部における乳頭層の配向構造を細胞核の分布とその局在を可視化することに成功し，薬剤浸透と皮膚内部の詳細な構造の計測を行なった．２）共焦点顕微鏡を用いて，皮膚表面に付した薬剤の経皮吸収量の計測法の構築を行なった．皮膚に付した薬剤モデル内の蛍光輝度の時間的変化について，高速共焦点スキャナーを使用して計測することで，これまで我々が提案してきた共焦点顕微鏡による傾斜観察法を発展的に応用し，観察面を傾斜させ奥行き方向の浸透を同時刻に計測する手法を開発し，薬剤濃度の時間変化から皮膚内部へと浸透する経皮吸収薬剤量のリアルタイム計測に成功した．また，皮膚にせん断付加を作用させる機械的摺動装置の設計及び開発を行った．
Development of low interference material for blood flow

KIKUCHI Kenji

Offer Organization: Japan Society for the Promotion of Science

System: Grants-in-Aid for Scientific Research Grant-in-Aid for Young Scientists (B)

Category: Grant-in-Aid for Young Scientists (B)

2013/04/01 - 2015/03/31

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We have been developing the wall shear stress on the hydrogel surface to measure the velocity gradient near the wall. This technique has some remarkable characteristics as non-invasive, high spatial, high time and resolution. Especially the flow on opaque material surface was also measured using our present system due to measure the velocity fields above the flow surface. Using our technique we revealed that the hydrogel surface has a drag reduction because of a slip flow, and it increase with its swelling degree due to a pore size of polymer chain structure.
血流との干渉が小さい生体材料の開発研究 Competitive

菊地謙次

Offer Organization: 日本学術振興会

System: 若手研究(B)

2013/04 - 2014/03

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低摩擦性を持つ生体高分子表面上の壁面せん断応力を非侵襲で計測する手法として，生体表面上の流れを直接計測することでせん断力を計測・評価する手法を提案した．従来法とは異なり力学センサを必要としない新たな壁面せん断力手法を開発したことにより，様々な表面状態によってもその表面上のせん断力計測を可能とした．また，表面における壁面せん断応力は，生体高分子表面における分子鎖間隙に深く関連し，本研究期間においてその分子鎖間隙と摩擦低減率について定量的に評価した．
Micro interference among surface and inside of hydrogel, surround fluid Competitive

KIKUCHI Kenji, MOCHIZUKI Osamu

Offer Organization: Japan Society for the Promotion of Science

System: Grants-in-Aid for Scientific Research Grant-in-Aid for Research Activity Start-up

Category: Grant-in-Aid for Research Activity Start-up

Institution: Toyo University

2009/04 - 2010/03

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The flow on a hydrogel surface was investigated for clarifying an effect of the surface flow to a living cell because the surface of a living cell resembles a hydrogel. The thin film-flow along the surface was measured by using a micro PIV (Particle Image Velocimetry) system. The flow near the hydrogel surface was slipped in our experiment. The magnitude of the slip related with the swelling degree and molecular weight of hydrogel materials. The slip flow on hydrogel surface was useful for the reduction of the wall shear stress because the decreasing of velocity gradient near the wall surface. It was worth observation that the slip flow near the surface induced the water flow inside the hydrogel.
μ-TAS適用超小型ポンプ開発を目的とした蚊の吸血機能の解明 Competitive

菊地謙次

Offer Organization: 日本学術振興会

System: 特別研究員奨励費

Category: 特別研究員奨励費

Institution: 東洋大学

2007/04 - 2008/03

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蚊の吸血性能に関して,工学的アプローチにより実験的に調べてきた結果.(1)周期的な吸い込みと1周期中の規則的血液吸い込み速度変動.(2)蚊吸血針内における速度分布,(3)蚊頭部(ポンプを含む)の断層像,(4)吸血針内部表面組織の表面構造,(5)頭部内に備わる2連ポンプのポンプ運動周期,を計測するに至った.その成果として,蚊の吸血機構における吸い込み流量1.32×10^<-11>m^3/s,吸い込み出力は2.37×10^<-7>Wであることが明らかとなった.蚊の頭部内に二つのポンプはほぼ逆位相で運動していることが明らかとなり,これまで未解明であったポンプの運動周期を定量的に計測するに至った.蚊の吸血機構の出力は,既存の人工マイクロポンプと出力を比較すると最小のマイクロポンプと比べ約10,000分の一であるものの,容積は約1,000分の一となり寸法に対する効率は非常に高く,高効率人工ポンプと同等の効率で駆動されていることが明らかとなった.その蚊の吸血ポンプの断面形状は,拡張時にルーローの三角形の形状を成すことが明らかとなった.さらに幾何学的にルーローの三角形の膨張比を算出すると,他の多角定幅図形より大きい膨張比であることが明らかとなった.このルーローの三角形を利用したマイクロロータリーポンプの設計を行い,その模型を作り性能評価を行った.

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Social Activities 1

日本機械学会流体工学部門流れのふしぎ展

2013/10/01 - Present

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身の回りの流れに関わる現象について，科学教室，体験型展示や工作教室を通じて紹介．日本科学未来館で開催し，例年約２０００人が来展．

Media Coverage 10

「大きな粒子が浮上小さな粒子が沈降微生物由来の興味深い現象発見」

科学新聞

2022/12/21

Type: Newspaper, magazine
「Yeast Cells Cause Embedded Objects to Rise via The Microbial Brazil Nut Effect」

EurekAlert, Asia Research News, AlphaGalileo, NewsBreak, Flipboard, Florida News Times他

2022/12/08

Type: Internet
「Yeast Cells Cause Embedded Objects to Rise via The Microbial Brazil Nut Effect」

2022/12/08

Type: Other
腸の活発な運動で促進される糖質吸収の可視化に成功 Myself

東北大学プレスリリース

2022/09/22

Type: Other
「Visualization of the "Brazil nut effect," an interesting phenomenon of microbial origin」

2022/02/01

Type: Internet
「东北大学实现“巴西果效应”可视化，大颗粒上浮、小颗粒下沉」

客觀日本

2021/12/21

Type: Internet
「東北大、微粒子内に沈降したプラスチックごみなどの物体が酵母の発酵時の炭酸ガスの発泡によって浮上することを発見」

日本経済新聞

2021/11/18

Type: Internet
マスクなどの摩擦刺激で皮膚が脆弱化する仕組みを解明

東北大学プレスリリース

2020/08/21
蚊がゴクゴクとゴックンを飲み分ける仕組みを発見 Myself

東北大学プレスリリース

2018/03/22
デッドエンドを回避する微生物の仕組みを発見

東北大学プレスリリース

2018/03/01

Type: Other

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