Fecal incontinence(FI),which can arise from various pathogenic mechanisms,has attracted considerable attention worldwide.Despite its importance,the reproduction of the defecatory system to study the mechanisms of FI r...Fecal incontinence(FI),which can arise from various pathogenic mechanisms,has attracted considerable attention worldwide.Despite its importance,the reproduction of the defecatory system to study the mechanisms of FI remains limited,largely because of social stigma and being considered inappropriate.Inspired by the rectum’s functionalities,we developed a soft robotic system that includes a power supply,pressure sensors,data acquisition systems,a flushing mechanism,stages,and a rectal module.Specifically,the innovative soft rectal module includes actuators inspired by sphincter muscles,both soft and rigid covers,and a soft rectum mold.The rectal mold,which was fabricated from materials that mimic human rectal tissue,was produced using a mold replication fabrication method.Both the soft and rigid components of the mold were created using three-dimensional(3D)printing technology.In addition,the sphincter muscle-inspired actuators featured double-layer pouch structures that were modeled and optimized based on multilayer perceptron methods to obtain a high contraction ratio(100%),generate high pressure(9.8 kPa),and have a short recovery time(3 s).Upon assembly,this defecation robot could smoothly expel liquid feces,perform controlled solid fecal cutting,and defecate extremely solid long feces,thus closely replicating the functions of the human rectum and anal canal.This defecation robot has the potential to facilitate human understanding of the complex defecation system and contribute to the development of improved quality-of-life devices related to defecation.展开更多
Adult bone structural integrity is maintained by remodeling via the coupling of osteoclastic bone resorption and osteoblastic bone formation.Osteocytes or osteoblasts express receptor activator of nuclear factor k-B l...Adult bone structural integrity is maintained by remodeling via the coupling of osteoclastic bone resorption and osteoblastic bone formation.Osteocytes or osteoblasts express receptor activator of nuclear factor k-B ligand(Rankl)or osteoprotegerin(Opg)to promote or inhibit osteoclastogenesis,respectively.Bone morphogenetic protein(BMP)is a potent bone inducer,but its major role in adult bone is to induce osteocytes to upregulate sclerostin(Sost)and increase the Rankl/Opg expression ratio,resulting in promotion of osteoclastogenesis.However,the precise effect of BMP-target gene(s)in osteoblasts on the Rankl/Opg expression ratio remains unclear.In the present study,we identified atonal homolog 8(Atoh8),which is directly upregulated by the BMPSmadl axis in osteoblasts.In vivo,Atoh8 was detected in osteoblasts but not osteocytes in adult mice.Although global Atoh8-knockout mice showed only a mild phenotype in the neonate skeleton,the bone volume was decreased and osteoclasts were increased in the adult phase.Atoh8-null marrow stroma cells were more potent than wild-type cells in inducing osteoclastogenesis in marrow cells.Atoh8 loss in osteoblasts increased Runx2 expression and the Rankl/Opg expression ratio,while Runx2 knockdown normalized the Rankl/Opg expression ratio.Moreover,Atoh8 formed a protein complex with Runx2 to inhibit Runx2 transcriptional activity and decrease the Rankl/Opg expression ratio.These results suggest that bone remodeling is regulated elaborately by BMP signaling;while BMP primarily promotes bone resorption,it simultaneously induces Atoh8 to inhibit Runx2 and reduce the Rankl/Opg expression ratio in osteoblasts,suppressing osteoclastogenesis and preventing excessive BMP-mediated bone resorption.展开更多
Coronavirus disease 2019(COVID-19) is known to present with respiratory symptoms,which can lead to severe pneumonia and respiratory failure.However,it can have multisystem complications such as cardiovascular manifest...Coronavirus disease 2019(COVID-19) is known to present with respiratory symptoms,which can lead to severe pneumonia and respiratory failure.However,it can have multisystem complications such as cardiovascular manifestations.The cardiovascular manifestations reported comprise myocarditis,cardiogenic shock,arrhythmias,pulmonary embolism,deep vein embolism,acute heart failure,and myocardial infarction.There is also an indirect impact of the pandemic on the management of cardiovascular care that has been shown clearly in multiple publications.In this review,we summarize the deadly relation of COVID-19 with cardiovascular events and the wider impact on several cardiovascular care areas by the pandemic situation。展开更多
Flexible electrohydrodynamic(EHD)pumps have been developed and applied in many fields due to no transmission structure,no wear,easy manipulation,and no noise.Physical simulation is often used to predict the output per...Flexible electrohydrodynamic(EHD)pumps have been developed and applied in many fields due to no transmission structure,no wear,easy manipulation,and no noise.Physical simulation is often used to predict the output performance of flexible EHD pumps.However,this method neglects fluid–solid interaction and energy loss caused by flexible materials,which are both difficult to calculate when the flexible pumps deform.Therefore,this study proposes a flexible pump output performance prediction using machine learning algorithms.We used three different types of machine learning:random forest regression,ridge regression,and neural network to predict the critical parameters(pressure,flow rate,and power)of the flexible EHD pump.Voltage,angle,gap,overlap,and channel height are selected as five input data of the neural network.In addition,we optimized essential parameters in the three networks.Finally,we adopt the best predictive model and evaluate the significance of five input parameters to the output performance of the flexible EHD pumps.Among the three methods,the MLP model has exceptionally high accuracy in predicting pressure and flow.Our work is beneficial for the design process of fluid sources in flexible soft actuators and soft hydraulic sources in microfluidic chips.展开更多
Soft robotics is a breakthrough technology to support human-robot interactions.The soft structure of a soft robot can increase safety during human and robot interactions.One of the promising soft actuators for soft ro...Soft robotics is a breakthrough technology to support human-robot interactions.The soft structure of a soft robot can increase safety during human and robot interactions.One of the promising soft actuators for soft robotics is dielectric elastomer actuators(DEAs).DEAs can operate silently and have an excellent energy density.The simple structure of DEAs leads to the easy fabrication of soft actuators.The simplicity combined with silent operation and high energy density make DEAs interesting for soft robotics researchers.DEAs actuation follows the Maxwell-pressure principle.The pressure produced in the DEAs actuation depends much on the voltage applied.Common DEAs requires high voltage to gain an actuation.Since the power consumption of DEAs is in the milli-Watt range,the current needed to operate the DEAs can be neglected.Several commercially available DC-DC converters can convert the volt range to the kV range.In order to get a voltage in the 2-3 kV range,the reliable DC-DC converter can be pricy for each device.This problem hinders the education of soft actuators,especially for a newcomer laboratory that works in soft electric actuators.This paper introduces an entirely do-it-yourself(DIY)Ultrahigh voltage amplifier(UHV-Amp)for education in soft robotics.UHV-Amp can amplify 12 V to at a maximum of 4 kV DC.As a demonstration,we used this UHV-Amp to test a single layer of powdered-based DEAs.The strategy to build this educational type UHV-Amp was utilizing a Cockcroft-Walton circuit structure to amplify the voltage range to the kV range.In its current state,the UHV-Amp has the potential to achieve approximately 4 kV.We created a simple platform to control the UHV-Amp from a personal computer.In near future,we expect this easy control of the UHV-Amp can contribute to the education of soft electric actuators.展开更多
The importance of actuators that can be integrated with flexible robot structures and mechanisms has increased in recent years with the advance of soft robotics.In particular,electrohydrodynamic(EHD)actuators,which ha...The importance of actuators that can be integrated with flexible robot structures and mechanisms has increased in recent years with the advance of soft robotics.In particular,electrohydrodynamic(EHD)actuators,which have expandable integrability to adapt to the flexible motion of soft robots,have received much attention in the field of soft robotics.Studies have deepened the understanding of steady states of EHD phenomena but nonsteady states are not well understood.We herein observe the development process of fluid in a microchannel adopting a Schlieren technique with the aid of a high-speed camera.In addition,we analyze the behavior of fluid flow in a microchannel that is designed to have pairs of parallel plate electrodes adopting a computational fluid dynamics technique.Results indicate the importance of considering flow generated by electrostatic energy,which tends to be ignored in constructing and evaluating EHD devices,and by the body force generated by the ion-drag force.By considering these effects,we estimate the development process of EHD flow and confirm the importance of considering the generation of vortices and their interactions inside the microchannel during the development of EHD devices.展开更多
The conventional electrohydrodynamic(EHD)pump is limited to pumping functional and dielectric liquids,which restricts its applications in fields like microfluidics,food safety,and materials production.In this study,we...The conventional electrohydrodynamic(EHD)pump is limited to pumping functional and dielectric liquids,which restricts its applications in fields like microfluidics,food safety,and materials production.In this study,we present a flexible water pump driven by EHD fluid,achieved by integrating valveless elements into the fluidic channel.Our approach leverages the water–EHD interface to propel the immiscible aqueous liquid and reciprocate this process using the nozzle–diffuser system.All components of the water pump are digitally fabricated and assembled.The valveless parts are created using a laser cutting machine.Additionally,we develop a model for the EHD pump and nozzle-diffuser system to predict the generated flow rate,considering factors such as the asymmetrical performance of the EHD pump,pulse frequency,applied voltage,and structural parameters.Finally,we experimentally characterize the flow rates of both the EHD pump and water pump and apply the newly developed device to air bubble manipulation and droplet generation.This research broadens the range of specialized liquids pumped by EHD pumps to include other aqueous liquids or mixtures.展开更多
基金supported by Grant-in-Aid for Scientific Research on Innovative Areas from the Japan Society for the Promotion of Science(Nos.18H05473 and 23K13290).
文摘Fecal incontinence(FI),which can arise from various pathogenic mechanisms,has attracted considerable attention worldwide.Despite its importance,the reproduction of the defecatory system to study the mechanisms of FI remains limited,largely because of social stigma and being considered inappropriate.Inspired by the rectum’s functionalities,we developed a soft robotic system that includes a power supply,pressure sensors,data acquisition systems,a flushing mechanism,stages,and a rectal module.Specifically,the innovative soft rectal module includes actuators inspired by sphincter muscles,both soft and rigid covers,and a soft rectum mold.The rectal mold,which was fabricated from materials that mimic human rectal tissue,was produced using a mold replication fabrication method.Both the soft and rigid components of the mold were created using three-dimensional(3D)printing technology.In addition,the sphincter muscle-inspired actuators featured double-layer pouch structures that were modeled and optimized based on multilayer perceptron methods to obtain a high contraction ratio(100%),generate high pressure(9.8 kPa),and have a short recovery time(3 s).Upon assembly,this defecation robot could smoothly expel liquid feces,perform controlled solid fecal cutting,and defecate extremely solid long feces,thus closely replicating the functions of the human rectum and anal canal.This defecation robot has the potential to facilitate human understanding of the complex defecation system and contribute to the development of improved quality-of-life devices related to defecation.
基金This study was supported by research grants from the Japan Society for the Promotion of Science,KAKENHI:grant-in-aid for scientific research(C)(grant Nos.15K10486,17K10933,and 18K09111).We thank K.Yuki(the University of Tokyo)for mouse careHui Gao for technical assistance+1 种基金Isozo,Inc.for bone histomorphometry andμ-CT analysesand Bio Matrix Research Inc.for microarray analysis.
文摘Adult bone structural integrity is maintained by remodeling via the coupling of osteoclastic bone resorption and osteoblastic bone formation.Osteocytes or osteoblasts express receptor activator of nuclear factor k-B ligand(Rankl)or osteoprotegerin(Opg)to promote or inhibit osteoclastogenesis,respectively.Bone morphogenetic protein(BMP)is a potent bone inducer,but its major role in adult bone is to induce osteocytes to upregulate sclerostin(Sost)and increase the Rankl/Opg expression ratio,resulting in promotion of osteoclastogenesis.However,the precise effect of BMP-target gene(s)in osteoblasts on the Rankl/Opg expression ratio remains unclear.In the present study,we identified atonal homolog 8(Atoh8),which is directly upregulated by the BMPSmadl axis in osteoblasts.In vivo,Atoh8 was detected in osteoblasts but not osteocytes in adult mice.Although global Atoh8-knockout mice showed only a mild phenotype in the neonate skeleton,the bone volume was decreased and osteoclasts were increased in the adult phase.Atoh8-null marrow stroma cells were more potent than wild-type cells in inducing osteoclastogenesis in marrow cells.Atoh8 loss in osteoblasts increased Runx2 expression and the Rankl/Opg expression ratio,while Runx2 knockdown normalized the Rankl/Opg expression ratio.Moreover,Atoh8 formed a protein complex with Runx2 to inhibit Runx2 transcriptional activity and decrease the Rankl/Opg expression ratio.These results suggest that bone remodeling is regulated elaborately by BMP signaling;while BMP primarily promotes bone resorption,it simultaneously induces Atoh8 to inhibit Runx2 and reduce the Rankl/Opg expression ratio in osteoblasts,suppressing osteoclastogenesis and preventing excessive BMP-mediated bone resorption.
文摘Coronavirus disease 2019(COVID-19) is known to present with respiratory symptoms,which can lead to severe pneumonia and respiratory failure.However,it can have multisystem complications such as cardiovascular manifestations.The cardiovascular manifestations reported comprise myocarditis,cardiogenic shock,arrhythmias,pulmonary embolism,deep vein embolism,acute heart failure,and myocardial infarction.There is also an indirect impact of the pandemic on the management of cardiovascular care that has been shown clearly in multiple publications.In this review,we summarize the deadly relation of COVID-19 with cardiovascular events and the wider impact on several cardiovascular care areas by the pandemic situation。
基金supported by Grant-in-Aid for Early-Career Scientists from the Japan Society for the Promotion of Science(23K13290),Japan.
文摘Flexible electrohydrodynamic(EHD)pumps have been developed and applied in many fields due to no transmission structure,no wear,easy manipulation,and no noise.Physical simulation is often used to predict the output performance of flexible EHD pumps.However,this method neglects fluid–solid interaction and energy loss caused by flexible materials,which are both difficult to calculate when the flexible pumps deform.Therefore,this study proposes a flexible pump output performance prediction using machine learning algorithms.We used three different types of machine learning:random forest regression,ridge regression,and neural network to predict the critical parameters(pressure,flow rate,and power)of the flexible EHD pump.Voltage,angle,gap,overlap,and channel height are selected as five input data of the neural network.In addition,we optimized essential parameters in the three networks.Finally,we adopt the best predictive model and evaluate the significance of five input parameters to the output performance of the flexible EHD pumps.Among the three methods,the MLP model has exceptionally high accuracy in predicting pressure and flow.Our work is beneficial for the design process of fluid sources in flexible soft actuators and soft hydraulic sources in microfluidic chips.
基金This work was supported by Japan Society for the Promotion of Science,Japan for their support under Grants-in-Aid for Scientific Research on Innovative Areas(18H05473)the JSPS,Japan KAKENHI(21J15489 and 23K13290).
文摘Soft robotics is a breakthrough technology to support human-robot interactions.The soft structure of a soft robot can increase safety during human and robot interactions.One of the promising soft actuators for soft robotics is dielectric elastomer actuators(DEAs).DEAs can operate silently and have an excellent energy density.The simple structure of DEAs leads to the easy fabrication of soft actuators.The simplicity combined with silent operation and high energy density make DEAs interesting for soft robotics researchers.DEAs actuation follows the Maxwell-pressure principle.The pressure produced in the DEAs actuation depends much on the voltage applied.Common DEAs requires high voltage to gain an actuation.Since the power consumption of DEAs is in the milli-Watt range,the current needed to operate the DEAs can be neglected.Several commercially available DC-DC converters can convert the volt range to the kV range.In order to get a voltage in the 2-3 kV range,the reliable DC-DC converter can be pricy for each device.This problem hinders the education of soft actuators,especially for a newcomer laboratory that works in soft electric actuators.This paper introduces an entirely do-it-yourself(DIY)Ultrahigh voltage amplifier(UHV-Amp)for education in soft robotics.UHV-Amp can amplify 12 V to at a maximum of 4 kV DC.As a demonstration,we used this UHV-Amp to test a single layer of powdered-based DEAs.The strategy to build this educational type UHV-Amp was utilizing a Cockcroft-Walton circuit structure to amplify the voltage range to the kV range.In its current state,the UHV-Amp has the potential to achieve approximately 4 kV.We created a simple platform to control the UHV-Amp from a personal computer.In near future,we expect this easy control of the UHV-Amp can contribute to the education of soft electric actuators.
基金supported by JSPS KAKENHI Grant Numbers JP19H02113,JP18J22908the Japan Society for the Promotion of Science of JRPs(Stretchable ElectroHydroDynamics).
文摘The importance of actuators that can be integrated with flexible robot structures and mechanisms has increased in recent years with the advance of soft robotics.In particular,electrohydrodynamic(EHD)actuators,which have expandable integrability to adapt to the flexible motion of soft robots,have received much attention in the field of soft robotics.Studies have deepened the understanding of steady states of EHD phenomena but nonsteady states are not well understood.We herein observe the development process of fluid in a microchannel adopting a Schlieren technique with the aid of a high-speed camera.In addition,we analyze the behavior of fluid flow in a microchannel that is designed to have pairs of parallel plate electrodes adopting a computational fluid dynamics technique.Results indicate the importance of considering flow generated by electrostatic energy,which tends to be ignored in constructing and evaluating EHD devices,and by the body force generated by the ion-drag force.By considering these effects,we estimate the development process of EHD flow and confirm the importance of considering the generation of vortices and their interactions inside the microchannel during the development of EHD devices.
基金supported by the Hirose Foundation(https://hirose-isf.or.jp/)Grant-in-Aid for Scientific Research on Innovative Areas(Research in a proposed research area)from the Japan Society for the Promotion of Science(Grant Nos.18H05473 and 23K13290)JRPs(Stretchable Electrohydrodynamic).
文摘The conventional electrohydrodynamic(EHD)pump is limited to pumping functional and dielectric liquids,which restricts its applications in fields like microfluidics,food safety,and materials production.In this study,we present a flexible water pump driven by EHD fluid,achieved by integrating valveless elements into the fluidic channel.Our approach leverages the water–EHD interface to propel the immiscible aqueous liquid and reciprocate this process using the nozzle–diffuser system.All components of the water pump are digitally fabricated and assembled.The valveless parts are created using a laser cutting machine.Additionally,we develop a model for the EHD pump and nozzle-diffuser system to predict the generated flow rate,considering factors such as the asymmetrical performance of the EHD pump,pulse frequency,applied voltage,and structural parameters.Finally,we experimentally characterize the flow rates of both the EHD pump and water pump and apply the newly developed device to air bubble manipulation and droplet generation.This research broadens the range of specialized liquids pumped by EHD pumps to include other aqueous liquids or mixtures.
