Peristalsis is widely seen in nature, as this pumping action is important in digestive systems for conveying sustenance to every corner of the body. In this paper, we propose a muscle-powered tubular micro pump that p...Peristalsis is widely seen in nature, as this pumping action is important in digestive systems for conveying sustenance to every corner of the body. In this paper, we propose a muscle-powered tubular micro pump that provides peristaltic transport. We utilized Drosophila melanogaster larvae that express channelrhodopsin-2 (ChR2) on the cell membrane of skeletal muscles to obtain light-responsive muscle tissues. The larvae were forced to contract with blue light stimulation. While changing the speed of the propagating light stimulation, we observed displacement on the surface of the contractile muscle tissues. We obtained peristaltic pumps from the larvae by dissecting them into tubular structures. The average inner diameter of the tubular structures was about 400 lm and the average outer diameter was about 750 lm. Contractions of this tubular structure could be controlled with the same blue light stimulation. To make the inner flow visible, we placed microbeads into the peristaltic pump, and thus determined that the pump could transport microbeads at a speed of 120 lm-s1.展开更多
Human-induced pluripotent stem cell (hiPSC)-derived cardiac patches have been extensively used for treating myocardialinfarction and have shown potential for clinical application. However, the limited patch thickness ...Human-induced pluripotent stem cell (hiPSC)-derived cardiac patches have been extensively used for treating myocardialinfarction and have shown potential for clinical application. However, the limited patch thickness can hamper its therapeuticeffect. We previously developed a fibrous scaffold that allowed the formation of well-organized cardiac tissue constructs. Inthe present study, based on the above technology, we developed a three-dimensional multilayer fibrous scaffold with dynamicperfusion, on which approximately 20 million hiPSC-derived cardiomyocytes (CMs) could be seeded in a single step andorganized into 1 mm thick and viable tissue. The multilayer cardiac tissue demonstrated enhanced contractile properties andupregulated cytokine secretion compared with the control group. Notably, when used on the myocardial infarction model,the multilayer group showed improved functional recovery and less fibrosis. These results indicated that the appropriatehiPSC-CM dose requires careful evaluation in developing clinical therapy. The multilayer cardiac tissue group demonstratedsignificant improvement than the control group, indicating that higher doses of transplanted cells may have improvedtherapeutic effects in treating myocardial infarction.展开更多
Rowing force of the middle leg of a water strider is one of the important factors affecting water repellency and applications in biomimetics,biomechanics,and biology.However,many previous studies have been based on es...Rowing force of the middle leg of a water strider is one of the important factors affecting water repellency and applications in biomimetics,biomechanics,and biology.However,many previous studies have been based on estimated leg rowing force and lack some credibility.Therefore,we tried to measure leg rowing force directly by a force transducer.In this article,we report the rowing force of water striders obtained by direct and indirect measurements.In the direct measurement,water striders were set onto a sensor system and the rowing force of a middle leg of the set water striders was directly measured using a bioappropriating probe(BAP),a kind of hook.In the indirect measurement,water striders were not fixed and the rowing force of locomoting water striders was evaluated by image analysis using a high-speed camera.As a result,we determined the rowing force by the direct measurement to be 955μN,while the rowing force by the indirect measurement was 493μN.We considered that the indirect measurement might lack some credibility because half the propellant energy was lost in the indirect force measurement due to various other factors.展开更多
Cockroaches can traverse unknown obstacle-terrain,self-right on the ground and climb above the obstacle.However,they have limited motion,such as less activity in light/bright areas and lower temperatures.Therefore,the...Cockroaches can traverse unknown obstacle-terrain,self-right on the ground and climb above the obstacle.However,they have limited motion,such as less activity in light/bright areas and lower temperatures.Therefore,the movement of the cyborg cockroaches needs to be optimized for the utilization of the cockroach as a cyborg insect.This study aims to increase the search rate and distance traveled by cockroaches and reduce the stop time by utilizing automatic stimulation from machine learning.Multiple machine learning classifiers were applied to classify the offline binary classification of the cockroach movement based on the inertial measuring unit input signals.Ten time-domain features were chosen and applied as the classifier inputs.The highest performance of the classifiers was implemented for the online motion recognition and automatic stimulation provided to the cerci to trigger the free walking motion of the cockroach.A user interface was developed to run multiple computational processes simultaneously in real time such as computer vision,data acquisition,feature extraction,automatic stimulation,and machine learning using a multithreading algorithm.On the basis of the experiment results,we successfully demonstrated that the movement performance of cockroaches was importantly improved by applying machine learning classification and automatic stimulation.This system increased the search rate and traveled distance by 68%and 70%,respectively,while the stop time was reduced by 78%.展开更多
基金supported by Grant-in-Aid for Japan Society for the Promotion of Science(JSPS)Fellow(17J01742)JSPS,MEXT KAKENHI(21676002,23111705,26249027,and 17H01254)the Industrial Technology Research Grant Program from the New Energy and Industrial Technology Development Organization(NEDO)of Japan
文摘Peristalsis is widely seen in nature, as this pumping action is important in digestive systems for conveying sustenance to every corner of the body. In this paper, we propose a muscle-powered tubular micro pump that provides peristaltic transport. We utilized Drosophila melanogaster larvae that express channelrhodopsin-2 (ChR2) on the cell membrane of skeletal muscles to obtain light-responsive muscle tissues. The larvae were forced to contract with blue light stimulation. While changing the speed of the propagating light stimulation, we observed displacement on the surface of the contractile muscle tissues. We obtained peristaltic pumps from the larvae by dissecting them into tubular structures. The average inner diameter of the tubular structures was about 400 lm and the average outer diameter was about 750 lm. Contractions of this tubular structure could be controlled with the same blue light stimulation. To make the inner flow visible, we placed microbeads into the peristaltic pump, and thus determined that the pump could transport microbeads at a speed of 120 lm-s1.
基金Osaka University.This research was supportedby the Japan Agency for Medical Research and Development(AMED)under GrantNumber jp22bm0204003hthe Japan Society for the Promotion of Science(JSPS)Grant-in-Aid for Scientific Research(A)under Grant Number 20H00542+1 种基金Grantin-Aidfor Scientific Research(B)under Grant Number(22H03157)X.Qu was supportedby the Ministry of Education,Culture,Sports,Science,and Technology(MEXT)scholarship.
文摘Human-induced pluripotent stem cell (hiPSC)-derived cardiac patches have been extensively used for treating myocardialinfarction and have shown potential for clinical application. However, the limited patch thickness can hamper its therapeuticeffect. We previously developed a fibrous scaffold that allowed the formation of well-organized cardiac tissue constructs. Inthe present study, based on the above technology, we developed a three-dimensional multilayer fibrous scaffold with dynamicperfusion, on which approximately 20 million hiPSC-derived cardiomyocytes (CMs) could be seeded in a single step andorganized into 1 mm thick and viable tissue. The multilayer cardiac tissue demonstrated enhanced contractile properties andupregulated cytokine secretion compared with the control group. Notably, when used on the myocardial infarction model,the multilayer group showed improved functional recovery and less fibrosis. These results indicated that the appropriatehiPSC-CM dose requires careful evaluation in developing clinical therapy. The multilayer cardiac tissue group demonstratedsignificant improvement than the control group, indicating that higher doses of transplanted cells may have improvedtherapeutic effects in treating myocardial infarction.
基金supported by the Japan Society for the Promotion of Science(JSPS)KAKENHI(grant number 22K03805)。
文摘Rowing force of the middle leg of a water strider is one of the important factors affecting water repellency and applications in biomimetics,biomechanics,and biology.However,many previous studies have been based on estimated leg rowing force and lack some credibility.Therefore,we tried to measure leg rowing force directly by a force transducer.In this article,we report the rowing force of water striders obtained by direct and indirect measurements.In the direct measurement,water striders were set onto a sensor system and the rowing force of a middle leg of the set water striders was directly measured using a bioappropriating probe(BAP),a kind of hook.In the indirect measurement,water striders were not fixed and the rowing force of locomoting water striders was evaluated by image analysis using a high-speed camera.As a result,we determined the rowing force by the direct measurement to be 955μN,while the rowing force by the indirect measurement was 493μN.We considered that the indirect measurement might lack some credibility because half the propellant energy was lost in the indirect force measurement due to various other factors.
基金supported by JSPS KAKENHI grant number 21K18700JST(Moonshot R&D)(grant number JPMJMS223A)。
文摘Cockroaches can traverse unknown obstacle-terrain,self-right on the ground and climb above the obstacle.However,they have limited motion,such as less activity in light/bright areas and lower temperatures.Therefore,the movement of the cyborg cockroaches needs to be optimized for the utilization of the cockroach as a cyborg insect.This study aims to increase the search rate and distance traveled by cockroaches and reduce the stop time by utilizing automatic stimulation from machine learning.Multiple machine learning classifiers were applied to classify the offline binary classification of the cockroach movement based on the inertial measuring unit input signals.Ten time-domain features were chosen and applied as the classifier inputs.The highest performance of the classifiers was implemented for the online motion recognition and automatic stimulation provided to the cerci to trigger the free walking motion of the cockroach.A user interface was developed to run multiple computational processes simultaneously in real time such as computer vision,data acquisition,feature extraction,automatic stimulation,and machine learning using a multithreading algorithm.On the basis of the experiment results,we successfully demonstrated that the movement performance of cockroaches was importantly improved by applying machine learning classification and automatic stimulation.This system increased the search rate and traveled distance by 68%and 70%,respectively,while the stop time was reduced by 78%.
