Transdermal microneedle(MN)patches are a promising tool used to transport a wide variety of active compounds into the skin.To serve as a substitute for common hypodermic needles,MNs must pierce the human stratum corne...Transdermal microneedle(MN)patches are a promising tool used to transport a wide variety of active compounds into the skin.To serve as a substitute for common hypodermic needles,MNs must pierce the human stratum corneum(~10 to 20μm),without rupturing or bending during penetration.This ensures that the cargo is released at the predetermined place and time.Therefore,the ability of MN patches to sufficiently pierce the skin is a crucial requirement.In the current review,the pain signal and its management during application of MNs and typical hypodermic needles are presented and compared.This is followed by a discussion on mechanical analysis and skin models used for insertion tests before application to clinical practice.Factors that affect insertion(e.g.,geometry,material composition and cross-linking of MNs),along with recent advancements in developed strategies(e.g.,insertion responsive patches and 3D printed biomimetic MNs using two-photon lithography)to improve the skin penetration are highlighted to provide a backdrop for future research.展开更多
Nature and technology often adopt structures that can be described as tubular helical assemblies.However,the role and mechanisms of these structures remain elusive.In this paper,we study the mechanical response under ...Nature and technology often adopt structures that can be described as tubular helical assemblies.However,the role and mechanisms of these structures remain elusive.In this paper,we study the mechanical response under compression and extension of a tubular assembly composed of 8 helical Kirchholf rods,arranged in pairs with opposite chirality and connected by pin joints,both analytically and numerically.We first focus on compression and find that,whereas a single helical rod would buckle,the rods of the assembly deform coherently as stable helical shapes wound around a common axis.Moreover,we investigate the response of the assembly under different boundary conditions,highlighting the emergence of a central region where rods remain circular helices.Secondly,we study the effects of different hypotheses on the elastic properties of rods,i.e.,stress-free rods when straight versus when circular helices,Kirchhoff’s rod model versus Sadowsky’s ribbon model.Summing up,our findings highlight the key role of mutual interactions in generating a stable ensemble response that preserves the helical shape of the individual rods,as well as some interesting features,and they shed some light on the reasons why helical shapes in tubular assemblies are so common and persistent in nature and technology.展开更多
As originally proposed by professor Alberto Corigliano of Politecnico di Milano and professor Jizeng Wang of Lanzhou University,the Chinese Society of Theoretical and Applied Mechanics(CSTAM)and the Italian Associatio...As originally proposed by professor Alberto Corigliano of Politecnico di Milano and professor Jizeng Wang of Lanzhou University,the Chinese Society of Theoretical and Applied Mechanics(CSTAM)and the Italian Association for Theoretical and Applied Mechanics(AIMETA)signed a memorandum of understanding on strengthening exchange and cooperation between mechanics scholars of the two countries in January,2018,officially opening the activities of bilateral academic exchange.展开更多
Variations in male body size are known to affect inter- and intrasexual selection outcomes in a wide range of animals. In mating systems involving sexual signaling before mating, body size often acts as a key factor a...Variations in male body size are known to affect inter- and intrasexual selection outcomes in a wide range of animals. In mating systems involving sexual signaling before mating, body size often acts as a key factor affecting signal strength and mate choice. We evaluated the effect of male size on courtship displays and mating success of the olive fruit fly, Bactrocera oleae （Diptera： Tephritidae）. Wing vibrations performed during successful and unsuccessful courtships by large and small males were recorded by high-speed videos and analyzed through frame-by-frame analysis. Mating success of large and small males was investigated. The effect of male-male competition on mating success was evaluated. Male body size affected both male courtship signals and mating outcomes. Successful males showed wing-borne signals with high frequencies and short interpulse intervals. Wing vibrations displayed by successful large males during copulation attempt had higher frequencies over smaller males and unsuccessful large males. In no-competition conditions, large males achieved higher mating success with respect to smaller ones. Allowing large and small males to compete for a female, large males achieve more mating success over smaller ones. Mate choice by females may be based on selection of the larger males, able to produce high-frequency wing vibrations. Such traits may be indicative of ＂good genes,＂ which under sexual selection could means good social-interaction genes, or a good competitive manipulator of conspecifics.展开更多
Lysiphlebus testaceipes （Hymenoptera： Braconidae： Aphidiinae） is a generalist endoparasitoid attacking more than 100 aphid species. In L. testaceipes, wing fanning is a main male courtship display evoked by a fema...Lysiphlebus testaceipes （Hymenoptera： Braconidae： Aphidiinae） is a generalist endoparasitoid attacking more than 100 aphid species. In L. testaceipes, wing fanning is a main male courtship display evoked by a female-borne sex pheromone. However, no information is available on the characteristics and behavioral role of male fanning during courtship in this parasitoid. Here, the courtship behavior of a wild strain ofL. testaceipes was quantified and the male wing fanning performances were analyzed through high-speed video recordings and examined in relation to mating success. Courtship sequence of wild L. testaceipes did not substantially differ from that previously reported for other populations mass reared on aphids. We observed that the male courtship duration did not affect mating success. However, video analysis revealed that the males producing high-frequency fanning signals achieved higher mating success over those that display low-frequency fanning. Wing fanning before successful and unsuccessful courtship differed in amplitude of wing movements and alignment toward the mate, highlighting that frontal courtship positively influence the female mating decisions. This study increases knowledge on sexual behavior in a key parasitoid of aphids, highlighting the importance of wing fanning among the range of sensory modalities used in the sexual communication ofL. testaceipes. From a practical point of view, this information is useful in L. testaceipes-based biocontrol strategies, since it can help to establish parameters for quality checking of mass-reared wasps over time.展开更多
Tens of crawling bio-robots with cockroaches as the mobile platform have been developed with various functions.Compared with artificial crawling robots of the same size,they revealed better flexibility,larger payload,...Tens of crawling bio-robots with cockroaches as the mobile platform have been developed with various functions.Compared with artificial crawling robots of the same size,they revealed better flexibility,larger payload,and stronger endurance.These features made bio-robots ideal for pipeline inspection scenarios because the advancements in locomotion mechanisms and efficient power systems are still hurdles for current artificial systems.In this study,we controlled the bio-robot to crawl in the confined dark pipeline and achieved autonomous motion control with the help of an onboard sensing system.Specifically,a micro-camera was mounted on the electronic backpack of the cockroach for image collection,and an IMU sensor was used to compute its body orientation.The electronic backpack transmitted images to the host computer for junction recognition and distance estimation.Meanwhile,the insect's habituation to electrical stimulation has long been an uncertain factor in the control of bio-robots.Here,a synergistic stimulation strategy was proposed to markedly reduce the habituation and increase the number of effective turning controls to over 100 times.It is also found that both the increase of payload and the application of stimulations could promote the metabolic rate by monitoring carbon dioxide release.With the integration of synergistic stimulation and autonomous control,we demonstrated the fully autonomous pipeline navigation with our cockroach bio-robot,which realized the cycle number of approximately 10 in a roll.This research provides a novel technology that has the potential for practical applications in the future.展开更多
Background:Accurate risk stratification of critically ill patients with coronavirus disease 2019(COVID-19)is essential for optimizing resource allocation,delivering targeted interventions,and maximizing patient surviv...Background:Accurate risk stratification of critically ill patients with coronavirus disease 2019(COVID-19)is essential for optimizing resource allocation,delivering targeted interventions,and maximizing patient survival probability.Machine learning(ML)techniques are attracting increased interest for the development of prediction models as they excel in the analysis of complex signals in data-rich environments such as critical care.Methods:We retrieved data on patients with COVID-19 admitted to an intensive care unit(ICU)between March and October 2020 from the RIsk Stratification in COVID-19 patients in the Intensive Care Unit(RISC-19-ICU)registry.We applied the Extreme Gradient Boosting(XGBoost)algorithm to the data to predict as a binary out-come the increase or decrease in patients’Sequential Organ Failure Assessment(SOFA)score on day 5 after ICU admission.The model was iteratively cross-validated in different subsets of the study cohort.Results:The final study population consisted of 675 patients.The XGBoost model correctly predicted a decrease in SOFA score in 320/385(83%)critically ill COVID-19 patients,and an increase in the score in 210/290(72%)patients.The area under the mean receiver operating characteristic curve for XGBoost was significantly higher than that for the logistic regression model(0.86 vs.0.69,P<0.01[paired t-test with 95%confidence interval]).Conclusions:The XGBoost model predicted the change in SOFA score in critically ill COVID-19 patients admitted to the ICU and can guide clinical decision support systems(CDSSs)aimed at optimizing available resources.展开更多
Direct stimulation of peripheral nerves with implantable electrodes successfully provided sensory feedback to amputees while using hand prostheses.Longevity of the electrodes is key to success,which we have improved f...Direct stimulation of peripheral nerves with implantable electrodes successfully provided sensory feedback to amputees while using hand prostheses.Longevity of the electrodes is key to success,which we have improved for the polyimide-based transverse intrafascicular multichannel electrode(TIME).The TIMEs were implanted in the median and ulnar nerves of three trans-radial amputees for up to six months.We present a comprehensive assessment of the electrical properties of the thin-film metallization as well as material status post explantationem.The TIMEs stayed within the electrochemical safe limits while enabling consistent and precise amplitude modulation.This lead to a reliable performance in terms of eliciting sensation.No signs of corrosion or morphological change to the thin-film metallization of the probes was observed by means of electrochemical and optical analysis.The presented longevity demonstrates that thin-film electrodes are applicable in permanent implant systems.展开更多
The capsule robot(CR)is a promising endoscopic method in gastrointestinal diagnosis because of its low discomfort to users.Most CRs are used to acquire image information only and lack the ability to collect samples.Al...The capsule robot(CR)is a promising endoscopic method in gastrointestinal diagnosis because of its low discomfort to users.Most CRs are used to acquire image information only and lack the ability to collect samples.Although some biopsy capsule robots(BCRs)have been developed,it remains challenging to acquire the intestinal tissue while avoiding tearing and adhesion due to the flexibility of colonic tissue.In this study,we develop a BCR with a novel sampling strategy in which soft tissue is scratched with sharp blades rotating at high speed to avoid tissue tearing.In the BCR design,a spiral spring with prestored energy is used to release high energy within a short period of time,which is dificult for a motor or magnet to perform within a small capacity installation space.The energy of the tightened spiral spring is transmitted to drive sharp blades to rotate quickly via a designed gear mechanism.To guarantee reliable sampling,a Bowden cable is used to transmit the user's manipulation to trigger the rotation of the blades,and the triggering force transmitted by the able can be monitored in real time by a force sensor installed at the manipulating end.A prototype of the proposed BCR is designed and fabricated,and its performance is tested through in vitro experiments.The results show that the proposed BCR is effective and the size of its acquired samples satisfies dinical requirements.展开更多
Nerve regeneration following traumas remains an unmet challenge.The application of pulsed electromagnetic field(PEMF)stimulation has gained traction for a minimally invasive regeneration of nerves.However,a sys-temati...Nerve regeneration following traumas remains an unmet challenge.The application of pulsed electromagnetic field(PEMF)stimulation has gained traction for a minimally invasive regeneration of nerves.However,a sys-tematic exploration of different PEMF parameters influencing neuron function at a cellular level is not available.In this study,we exposed neuroblastoma F11 cells to PEMF to trigger beneficial effects on neurite outgrowth.Different carrier frequencies,pulse repetition frequencies,and duty cycles were screened with a custom ad hoc setup to find the most influential parameters values.A carrier frequency of 13.5 MHz,a pulse repetition frequency of 20 Hz,and a duty cycle of 10%allowed maximal neurite outgrowth,with unaltered viability with respect to non-stimulated controls.Furthermore,in a longer-term analysis,such optimal conditions were also able to in-crease the gene expression of neuronal expression markers NeuN and Tuj-1 and transcription factor Ngn1.Finally,the same optimal stimulation conditions were also applied to THP-1 macrophages,and both pro-inflammatory(TNF-α,IL-1β,IL-6,IL-8)and anti-inflammatory cytokines(IL-10,CD206)were analyzed.The optimal PEMF stimulation parameters did not induce differentiation towards an M1 macrophage phenotype,decreased IL-1β and IL-8 gene expression,decreased TNF-α and IL-8 cytokine release in M1-differentiated cells,increased IL-10 and CD206 gene expression,as well as IL-10 cytokine release in M0 cells.The specific PEMF stimulation regime,which is optimal in vitro,might have a high potential for a future in vivo translation targeting neural regeneration and anti-inflammatory action for treating peripheral nerve injuries.展开更多
Temporary tattoo electrodes are the most recent development in the field of cutaneous sensors.They have successfully demonstrated their performances in the monitoring of various electrophysiological signals on the ski...Temporary tattoo electrodes are the most recent development in the field of cutaneous sensors.They have successfully demonstrated their performances in the monitoring of various electrophysiological signals on the skin.These epidermal electronic devices offer a conformal and imperceptible contact with the wearer while enabling good quality recordings over time.Evaluations of brain activity in clinical practice face multiple limitations,where such electrodes can provide realistic technological solutions and increase diagnostics efficiency.Here we present the performance of inkjet-printed conducting polymer tattoo electrodes in clinical electroencephalography and their compatibility with magnetoencephalography.The working mechanism of these dry sensors is investigated through the modeling of the skin/electrode impedance for better understanding of the biosignals transduction at this interface.Furthermore,a custom-made skin phantom platform demonstrates the feasibility of high-density recordings,which are essential in localizing neuropathological activities.These evaluations provide valuable input for the successful application of these ultrathin electronic tattoos sensors in multimodal brain monitoring and diagnosis.展开更多
Campoplex capitator is an ichneumonid parasitoid with a narrow host range,comprising grapevine moth pests.Despite being considered one of the possible candidates for biocontrol of Lobesia botrana,knowledge about its b...Campoplex capitator is an ichneumonid parasitoid with a narrow host range,comprising grapevine moth pests.Despite being considered one of the possible candidates for biocontrol of Lobesia botrana,knowledge about its biology is limited and massrearing for commercial purposes is still lacking.This research provides a quantitative analysis of the C.capitator courtship and mating behavior.C.capitator mating sequence was analyzed by high-speed video recordings.Main behavioral parameters,with special reference to male wing fanning and antennal tapping,were quantified and linked with mating success.Furthermore,we analyzed the occurrence of population-level behavioral asymmetries during C capitator sexual interactions and their impact on male success.Results showed that male wing fanning was crucial to successfully approach the female.Males achieving higher mating success performed wing-fanning at higher frequencies over unsuccessful ones.After wing fanning,most of males palpated the females body with their antennae,before attempting copulation.The overall mating success was>70%,with a rather long copula duration(254.76±14.21 s).Male wing-fanning was lateralized on the left at population level,while antennal tapping displays were right-biased.Sidebiased male displays do not differ in terms of frequency and duration of their main features.This research adds basic knowledge to the C.capitator behavioral ecology.Since rearing protocols for C.capitator are being developed male wing fanning frequency may represent a useful benchmark for monitoring mate quality over time,tackling mating success reductions due to prolonged mass-rearing.展开更多
基金the European Horizon 2020 Research and Innovation Programme under Grant Agreement No.899349(5D NanoPrinting).
文摘Transdermal microneedle(MN)patches are a promising tool used to transport a wide variety of active compounds into the skin.To serve as a substitute for common hypodermic needles,MNs must pierce the human stratum corneum(~10 to 20μm),without rupturing or bending during penetration.This ensures that the cargo is released at the predetermined place and time.Therefore,the ability of MN patches to sufficiently pierce the skin is a crucial requirement.In the current review,the pain signal and its management during application of MNs and typical hypodermic needles are presented and compared.This is followed by a discussion on mechanical analysis and skin models used for insertion tests before application to clinical practice.Factors that affect insertion(e.g.,geometry,material composition and cross-linking of MNs),along with recent advancements in developed strategies(e.g.,insertion responsive patches and 3D printed biomimetic MNs using two-photon lithography)to improve the skin penetration are highlighted to provide a backdrop for future research.
基金Open access funding provided by Scuola Superiore Sant’Anna within the CRUI-CARE Agreement.
文摘Nature and technology often adopt structures that can be described as tubular helical assemblies.However,the role and mechanisms of these structures remain elusive.In this paper,we study the mechanical response under compression and extension of a tubular assembly composed of 8 helical Kirchholf rods,arranged in pairs with opposite chirality and connected by pin joints,both analytically and numerically.We first focus on compression and find that,whereas a single helical rod would buckle,the rods of the assembly deform coherently as stable helical shapes wound around a common axis.Moreover,we investigate the response of the assembly under different boundary conditions,highlighting the emergence of a central region where rods remain circular helices.Secondly,we study the effects of different hypotheses on the elastic properties of rods,i.e.,stress-free rods when straight versus when circular helices,Kirchhoff’s rod model versus Sadowsky’s ribbon model.Summing up,our findings highlight the key role of mutual interactions in generating a stable ensemble response that preserves the helical shape of the individual rods,as well as some interesting features,and they shed some light on the reasons why helical shapes in tubular assemblies are so common and persistent in nature and technology.
基金We appreciate the efforts made by all the contributors for this thematic issue.We are grateful to the former Editor-in-Chief of Acta Mechanica Sinica,Prof.Tian Jian Lu,for inviting us as the vip editors of this issue.We also thank the current Editor-in-Chief Prof.Xiaojing Zheng and the former president of the CSTAM,Prof.Wei Yang,for their encouraging and support,and staff of the editorial office of Acta Mechanica Sinica for managing and assistance.J.Z.Wang thanks the support from the National Natural Science Foundation of China(Grant 11925204).
文摘As originally proposed by professor Alberto Corigliano of Politecnico di Milano and professor Jizeng Wang of Lanzhou University,the Chinese Society of Theoretical and Applied Mechanics(CSTAM)and the Italian Association for Theoretical and Applied Mechanics(AIMETA)signed a memorandum of understanding on strengthening exchange and cooperation between mechanics scholars of the two countries in January,2018,officially opening the activities of bilateral academic exchange.
文摘Variations in male body size are known to affect inter- and intrasexual selection outcomes in a wide range of animals. In mating systems involving sexual signaling before mating, body size often acts as a key factor affecting signal strength and mate choice. We evaluated the effect of male size on courtship displays and mating success of the olive fruit fly, Bactrocera oleae （Diptera： Tephritidae）. Wing vibrations performed during successful and unsuccessful courtships by large and small males were recorded by high-speed videos and analyzed through frame-by-frame analysis. Mating success of large and small males was investigated. The effect of male-male competition on mating success was evaluated. Male body size affected both male courtship signals and mating outcomes. Successful males showed wing-borne signals with high frequencies and short interpulse intervals. Wing vibrations displayed by successful large males during copulation attempt had higher frequencies over smaller males and unsuccessful large males. In no-competition conditions, large males achieved higher mating success with respect to smaller ones. Allowing large and small males to compete for a female, large males achieve more mating success over smaller ones. Mate choice by females may be based on selection of the larger males, able to produce high-frequency wing vibrations. Such traits may be indicative of ＂good genes,＂ which under sexual selection could means good social-interaction genes, or a good competitive manipulator of conspecifics.
文摘Lysiphlebus testaceipes （Hymenoptera： Braconidae： Aphidiinae） is a generalist endoparasitoid attacking more than 100 aphid species. In L. testaceipes, wing fanning is a main male courtship display evoked by a female-borne sex pheromone. However, no information is available on the characteristics and behavioral role of male fanning during courtship in this parasitoid. Here, the courtship behavior of a wild strain ofL. testaceipes was quantified and the male wing fanning performances were analyzed through high-speed video recordings and examined in relation to mating success. Courtship sequence of wild L. testaceipes did not substantially differ from that previously reported for other populations mass reared on aphids. We observed that the male courtship duration did not affect mating success. However, video analysis revealed that the males producing high-frequency fanning signals achieved higher mating success over those that display low-frequency fanning. Wing fanning before successful and unsuccessful courtship differed in amplitude of wing movements and alignment toward the mate, highlighting that frontal courtship positively influence the female mating decisions. This study increases knowledge on sexual behavior in a key parasitoid of aphids, highlighting the importance of wing fanning among the range of sensory modalities used in the sexual communication ofL. testaceipes. From a practical point of view, this information is useful in L. testaceipes-based biocontrol strategies, since it can help to establish parameters for quality checking of mass-reared wasps over time.
基金supported by the National Natural Science Foundation of China(grant number 52375011)Shenzhen Science and Technology Program(grant number RCBS-20210609103901011)+1 种基金Shenzhen Peacock Innovation Team Project(grant number KQTD20210811090146075)State Key Laboratory of Mechanical System and Vibration(grant number MSV202306).
文摘Tens of crawling bio-robots with cockroaches as the mobile platform have been developed with various functions.Compared with artificial crawling robots of the same size,they revealed better flexibility,larger payload,and stronger endurance.These features made bio-robots ideal for pipeline inspection scenarios because the advancements in locomotion mechanisms and efficient power systems are still hurdles for current artificial systems.In this study,we controlled the bio-robot to crawl in the confined dark pipeline and achieved autonomous motion control with the help of an onboard sensing system.Specifically,a micro-camera was mounted on the electronic backpack of the cockroach for image collection,and an IMU sensor was used to compute its body orientation.The electronic backpack transmitted images to the host computer for junction recognition and distance estimation.Meanwhile,the insect's habituation to electrical stimulation has long been an uncertain factor in the control of bio-robots.Here,a synergistic stimulation strategy was proposed to markedly reduce the habituation and increase the number of effective turning controls to over 100 times.It is also found that both the increase of payload and the application of stimulations could promote the metabolic rate by monitoring carbon dioxide release.With the integration of synergistic stimulation and autonomous control,we demonstrated the fully autonomous pipeline navigation with our cockroach bio-robot,which realized the cycle number of approximately 10 in a roll.This research provides a novel technology that has the potential for practical applications in the future.
基金supported by the“Microsoft Grant Award:AI for Health COVID-19″The RISC-19-ICU reg-istry is supported by the Swiss Society of Intensive Care Medicine and funded by internal resources of the Institute of Intensive Care Medicine,of the University Hospital Zurich and by unrestricted grants from CytoSorbents Europe GmbH(Berlin,Germany)+1 种基金Union Bancaire Privée(Zurich,Switzerland)The sponsors had no role in the design of the study,the collection and analysis of the data,or the preparation of the manuscript.
文摘Background:Accurate risk stratification of critically ill patients with coronavirus disease 2019(COVID-19)is essential for optimizing resource allocation,delivering targeted interventions,and maximizing patient survival probability.Machine learning(ML)techniques are attracting increased interest for the development of prediction models as they excel in the analysis of complex signals in data-rich environments such as critical care.Methods:We retrieved data on patients with COVID-19 admitted to an intensive care unit(ICU)between March and October 2020 from the RIsk Stratification in COVID-19 patients in the Intensive Care Unit(RISC-19-ICU)registry.We applied the Extreme Gradient Boosting(XGBoost)algorithm to the data to predict as a binary out-come the increase or decrease in patients’Sequential Organ Failure Assessment(SOFA)score on day 5 after ICU admission.The model was iteratively cross-validated in different subsets of the study cohort.Results:The final study population consisted of 675 patients.The XGBoost model correctly predicted a decrease in SOFA score in 320/385(83%)critically ill COVID-19 patients,and an increase in the score in 210/290(72%)patients.The area under the mean receiver operating characteristic curve for XGBoost was significantly higher than that for the logistic regression model(0.86 vs.0.69,P<0.01[paired t-test with 95%confidence interval]).Conclusions:The XGBoost model predicted the change in SOFA score in critically ill COVID-19 patients admitted to the ICU and can guide clinical decision support systems(CDSSs)aimed at optimizing available resources.
文摘Direct stimulation of peripheral nerves with implantable electrodes successfully provided sensory feedback to amputees while using hand prostheses.Longevity of the electrodes is key to success,which we have improved for the polyimide-based transverse intrafascicular multichannel electrode(TIME).The TIMEs were implanted in the median and ulnar nerves of three trans-radial amputees for up to six months.We present a comprehensive assessment of the electrical properties of the thin-film metallization as well as material status post explantationem.The TIMEs stayed within the electrochemical safe limits while enabling consistent and precise amplitude modulation.This lead to a reliable performance in terms of eliciting sensation.No signs of corrosion or morphological change to the thin-film metallization of the probes was observed by means of electrochemical and optical analysis.The presented longevity demonstrates that thin-film electrodes are applicable in permanent implant systems.
基金supported by the China National Key Research and Development Project(No.2019YFB1312404)the Natural Science Foundation of China(No.51975401).
文摘The capsule robot(CR)is a promising endoscopic method in gastrointestinal diagnosis because of its low discomfort to users.Most CRs are used to acquire image information only and lack the ability to collect samples.Although some biopsy capsule robots(BCRs)have been developed,it remains challenging to acquire the intestinal tissue while avoiding tearing and adhesion due to the flexibility of colonic tissue.In this study,we develop a BCR with a novel sampling strategy in which soft tissue is scratched with sharp blades rotating at high speed to avoid tissue tearing.In the BCR design,a spiral spring with prestored energy is used to release high energy within a short period of time,which is dificult for a motor or magnet to perform within a small capacity installation space.The energy of the tightened spiral spring is transmitted to drive sharp blades to rotate quickly via a designed gear mechanism.To guarantee reliable sampling,a Bowden cable is used to transmit the user's manipulation to trigger the rotation of the blades,and the triggering force transmitted by the able can be monitored in real time by a force sensor installed at the manipulating end.A prototype of the proposed BCR is designed and fabricated,and its performance is tested through in vitro experiments.The results show that the proposed BCR is effective and the size of its acquired samples satisfies dinical requirements.
文摘Nerve regeneration following traumas remains an unmet challenge.The application of pulsed electromagnetic field(PEMF)stimulation has gained traction for a minimally invasive regeneration of nerves.However,a sys-tematic exploration of different PEMF parameters influencing neuron function at a cellular level is not available.In this study,we exposed neuroblastoma F11 cells to PEMF to trigger beneficial effects on neurite outgrowth.Different carrier frequencies,pulse repetition frequencies,and duty cycles were screened with a custom ad hoc setup to find the most influential parameters values.A carrier frequency of 13.5 MHz,a pulse repetition frequency of 20 Hz,and a duty cycle of 10%allowed maximal neurite outgrowth,with unaltered viability with respect to non-stimulated controls.Furthermore,in a longer-term analysis,such optimal conditions were also able to in-crease the gene expression of neuronal expression markers NeuN and Tuj-1 and transcription factor Ngn1.Finally,the same optimal stimulation conditions were also applied to THP-1 macrophages,and both pro-inflammatory(TNF-α,IL-1β,IL-6,IL-8)and anti-inflammatory cytokines(IL-10,CD206)were analyzed.The optimal PEMF stimulation parameters did not induce differentiation towards an M1 macrophage phenotype,decreased IL-1β and IL-8 gene expression,decreased TNF-α and IL-8 cytokine release in M1-differentiated cells,increased IL-10 and CD206 gene expression,as well as IL-10 cytokine release in M0 cells.The specific PEMF stimulation regime,which is optimal in vitro,might have a high potential for a future in vivo translation targeting neural regeneration and anti-inflammatory action for treating peripheral nerve injuries.
文摘Temporary tattoo electrodes are the most recent development in the field of cutaneous sensors.They have successfully demonstrated their performances in the monitoring of various electrophysiological signals on the skin.These epidermal electronic devices offer a conformal and imperceptible contact with the wearer while enabling good quality recordings over time.Evaluations of brain activity in clinical practice face multiple limitations,where such electrodes can provide realistic technological solutions and increase diagnostics efficiency.Here we present the performance of inkjet-printed conducting polymer tattoo electrodes in clinical electroencephalography and their compatibility with magnetoencephalography.The working mechanism of these dry sensors is investigated through the modeling of the skin/electrode impedance for better understanding of the biosignals transduction at this interface.Furthermore,a custom-made skin phantom platform demonstrates the feasibility of high-density recordings,which are essential in localizing neuropathological activities.These evaluations provide valuable input for the successful application of these ultrathin electronic tattoos sensors in multimodal brain monitoring and diagnosis.
基金D.Romano is partially supported by the H2020 Project“Submarine cultures perform long-term robotic exploration of unconventional environmental niches”(sub-CULTron)[640967FP7].
文摘Campoplex capitator is an ichneumonid parasitoid with a narrow host range,comprising grapevine moth pests.Despite being considered one of the possible candidates for biocontrol of Lobesia botrana,knowledge about its biology is limited and massrearing for commercial purposes is still lacking.This research provides a quantitative analysis of the C.capitator courtship and mating behavior.C.capitator mating sequence was analyzed by high-speed video recordings.Main behavioral parameters,with special reference to male wing fanning and antennal tapping,were quantified and linked with mating success.Furthermore,we analyzed the occurrence of population-level behavioral asymmetries during C capitator sexual interactions and their impact on male success.Results showed that male wing fanning was crucial to successfully approach the female.Males achieving higher mating success performed wing-fanning at higher frequencies over unsuccessful ones.After wing fanning,most of males palpated the females body with their antennae,before attempting copulation.The overall mating success was>70%,with a rather long copula duration(254.76±14.21 s).Male wing-fanning was lateralized on the left at population level,while antennal tapping displays were right-biased.Sidebiased male displays do not differ in terms of frequency and duration of their main features.This research adds basic knowledge to the C.capitator behavioral ecology.Since rearing protocols for C.capitator are being developed male wing fanning frequency may represent a useful benchmark for monitoring mate quality over time,tackling mating success reductions due to prolonged mass-rearing.
