Invasive as well as non-invasive neurotechnologies conceptualized to interface the central and peripheral nervous system have been probed for the past decades,which refer to electroencephalography,electrocorticography...Invasive as well as non-invasive neurotechnologies conceptualized to interface the central and peripheral nervous system have been probed for the past decades,which refer to electroencephalography,electrocorticography and microelectrode arrays.The challenges of these mentioned approaches are characterized by the bandwidth of the spatiotemporal resolution,which in turn is essential for large-area neuron recordings(Abiri et al.,2019).展开更多
Fully implanted brain-computer interfaces(BCIs)are preferred as they eliminate signal degradation caused by interference and absorption in external tissues,a common issue in non-fully implanted systems.To optimize the...Fully implanted brain-computer interfaces(BCIs)are preferred as they eliminate signal degradation caused by interference and absorption in external tissues,a common issue in non-fully implanted systems.To optimize the design of electroencephalography electrodes in fully implanted BCI systems,this study investigates the penetration and absorption characteristics of microwave signals in human brain tissue at different frequencies.Electromagnetic simulations are used to analyze the power density distribution and specific absorption rate(SAR)of signals at various frequen-cies.The results indicate that lower-frequency signals offer advantages in terms of power density and attenuation coeffi-cients.However,SAR-normalized analysis,which considers both power density and electromagnetic radiation hazards,shows that higher-frequency signals perform better at superficial to intermediate depths.Specifically,at a depth of 2 mm beneath the cortex,the power density of a 6.5 GHz signal is 247.83%higher than that of a 0.4 GHz signal.At a depth of 5 mm,the power density of a 3.5 GHz signal exceeds that of a 0.4 GHz signal by 224.16%.The findings suggest that 6.5 GHz is optimal for electrodes at a depth of 2 mm,3.5 GHz for 5 mm,2.45 GHz for depths of 15-20 mm,and 1.8 GHz for 25 mm.展开更多
In recent years,with the continuous advancement of technolo-gies such as artificial intelligence,neurobiology,and sensors,braincomputer interface(Bcl)technology has embraced opportunitiesfor rapid development The"...In recent years,with the continuous advancement of technolo-gies such as artificial intelligence,neurobiology,and sensors,braincomputer interface(Bcl)technology has embraced opportunitiesfor rapid development The"Guidelines for the Establishment ofNeurological Medical Service Price ltems(Trial)"recently issued bythe National Healthcare Security Administration specifically sets upseparate prospective items for new BCl technologies,which will un-doubtedly strongly facilitate the clinical application of BCl technologyas soon as possible,benefiting a broad range of patients.展开更多
In this review article, we present more than a decade of our work on the development of brain–computer interface (BCI)systems for the restoration of walking following neurological injuries such as spinal cord injury ...In this review article, we present more than a decade of our work on the development of brain–computer interface (BCI)systems for the restoration of walking following neurological injuries such as spinal cord injury (SCI) or stroke. Most ofthis work has been in the domain of non-invasive electroencephalogram-based BCIs, including interfacing our system witha virtual reality environment and physical prostheses. Real-time online tests are presented to demonstrate the ability ofable-bodied subjects as well as those with SCI to purposefully operate our BCI system. Extensions of this work are alsopresented and include the development of a portable low-cost BCI suitable for at-home use, our ongoing eforts to develop afully implantable BCI for the restoration of walking and leg sensation after SCI, and our novel BCI-based therapy for strokerehabilitation.展开更多
The development of brain-computer interfaces(BCIs)has established a new communication channel between the brain and external devices for information transmission that requires no muscular signals[1].BCIs have been pre...The development of brain-computer interfaces(BCIs)has established a new communication channel between the brain and external devices for information transmission that requires no muscular signals[1].BCIs have been preliminarily studied to improve motor functions in patients with severe motor disabilities,especially lock-in syndrome.At present,the application of BCIs has been extensively validated.展开更多
Brain-computer interface(BCI)technology is rapidly advancing in medical research and application.As an emerging biomedical engineering technology,it has garnered significant attention in the clinical research of brain...Brain-computer interface(BCI)technology is rapidly advancing in medical research and application.As an emerging biomedical engineering technology,it has garnered significant attention in the clinical research of brain disease diagnosis and treatment,neurological rehabilitation,and mental health.However,BCI also raises several challenges and ethical concerns in clinical research.In this article,the authors investigate and discuss three aspects of BCI in medicine and healthcare:the state of international ethical governance,multidimensional ethical challenges pertaining to BCI in clinical research,and suggestive concerns for ethical review.Despite the great potential of frontier BCI research and development in the field of medical care,the ethical challenges induced by itself and the complexities of clinical research and brain function have put forward new special fields for ethics in BCI.To ensure"responsible innovation"in BCI research in healthcare and medicine,the creation of an ethical global governance framework and system,along with special guidelines for cutting-edge BCI research in medicine,is suggested.展开更多
In this review, five graphical user interfaces(GUIs) used in radiation therapy practices and researches are introduced. They are:(1) the treatment time calculator, superficialx-ray treatment time calculator(SUPCALC) u...In this review, five graphical user interfaces(GUIs) used in radiation therapy practices and researches are introduced. They are:(1) the treatment time calculator, superficialx-ray treatment time calculator(SUPCALC) used in the superficial X-ray radiation therapy;(2) the monitor unit calculator, electron monitor unit calculator(EMUC) used in the electron radiation therapy;(3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy(SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy;(4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and(5) the monitor unit calculator, photon beam monitor unit calculator(PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls the multileaf collimator to deliver intensity modulated beams for a specific fluence map used in quality assurance or research. DOSCTP is a treatment planning system using the computed tomography images. Radiation beams(photon or electron) with different energies and field sizes produced by a linear accelerator can be placed in different positions to irradiate the tumour in the patient. DOSCTP is linked to a Monte Carlo simulation engine using the EGSnrc-based code, so that 3D dose distribution canbe determined accurately for radiation therapy. Moreover, DOSCTP can be used for treatment planning of patient or small animal. PMUC is a GUI for calculation of the monitor unit based on the prescription dose of patient in photon beam radiation therapy. The calculation is based on dose corrections in changes of photon beam energy, treatment depth, field size, jaw position, beam axis, treatment distance and beam modifiers. All GUIs mentioned in this review were written either by the Microsoft Visual Basic.net or a MATLAB GUI development tool called GUIDE. In addition, all GUIs were verified and tested using measurements to ensure their accuracies were up to clinical acceptable levels for implementations.展开更多
Disorders of consciousness(DoCs) are chronic conditions resulting usually from severe neurological deficits. The limitations of the existing diagnosis systems and methodologies cause a need for additional tools for re...Disorders of consciousness(DoCs) are chronic conditions resulting usually from severe neurological deficits. The limitations of the existing diagnosis systems and methodologies cause a need for additional tools for relevant patients with DoCs assessment, including brain-computer interfaces(BCIs). Recent progress in BCIs' clinical applications may offer important breakthroughs in the diagnosis and therapy of patients with DoCs. Thus the clinical significance of BCI applications in the diagnosis of patients with DoCs is hard to overestimate. One of them may be brain-computer interfaces. The aim of this study is to evaluate possibility of non-invasive EEG-based brain-computer interfaces in diagnosis of patients with DOCs in post-acute and long-term care institutions.展开更多
Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly urgent.Multi-component interface engineering is con...Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly urgent.Multi-component interface engineering is considered an effective means to achieve high-efficiency EMW absorption.However,interface modulation engineering has not been fully discussed and has great potential in the field of EMW absorption.In this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal reduction.By utilizing the different properties of different substances,rich heterogeneous interfaces are constructed.This effectively promotes charge transfer and enhances interfacial polarization and conduction loss.The prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy resin.The minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 GHz.Moreover,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel surfaces.Therefore,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.展开更多
Brain-computer interfaces(BCIs)represent an emerging technology that facilitates direct communication between the brain and external devices.In recent years,numerous review articles have explored various aspects of BC...Brain-computer interfaces(BCIs)represent an emerging technology that facilitates direct communication between the brain and external devices.In recent years,numerous review articles have explored various aspects of BCIs,including their fundamental principles,technical advancements,and applications in specific domains.However,these reviews often focus on signal processing,hardware development,or limited applications such as motor rehabilitation or communication.This paper aims to offer a comprehensive review of recent electroencephalogram(EEG)-based BCI applications in the medical field across 8 critical areas,encompassing rehabilitation,daily communication,epilepsy,cerebral resuscitation,sleep,neurodegenerative diseases,anesthesiology,and emotion recognition.Moreover,the current challenges and future trends of BCIs were also discussed,including personal privacy and ethical concerns,network security vulnerabilities,safety issues,and biocompatibility.展开更多
An electroencephalogram(EEG)signal projection using kernel discriminative locality preserving canonical correlation analysis(KDLPCCA)-based correlation with steady-state visual evoked potential(SSVEP)templates for fre...An electroencephalogram(EEG)signal projection using kernel discriminative locality preserving canonical correlation analysis(KDLPCCA)-based correlation with steady-state visual evoked potential(SSVEP)templates for frequency recognition is presented in this paper.With KDLPCCA,not only a non-linear correlation but also local properties and discriminative information of each class sample are considered to extract temporal and frequency features of SSVEP signals.The new projected EEG features are classified with classical machine learning algorithms,namely,K-nearest neighbors(KNNs),naive Bayes,and random forest classifiers.To demonstrate the effectiveness of the proposed method,16-channel SSVEP data corresponding to 4 frequencies collected from 5 subjects were used to evaluate the performance.Compared with the state of the art canonical correlation analysis(CCA),experimental results show significant improvements in classification accuracy and information transfer rate(ITR),achieving 100%and 240 bits/min with 0.5 s sample block.The superior performance demonstrates that this method holds the promising potential to achieve satisfactory performance for high-accuracy SSVEP-based brain-computer interfaces.展开更多
The Brain-Computer Interfaces(BCIs)had been proposed and used in therapeutics for decades.However,the need of time-consuming calibration phase and the lack of robustness,which are caused by little-labeled data,are res...The Brain-Computer Interfaces(BCIs)had been proposed and used in therapeutics for decades.However,the need of time-consuming calibration phase and the lack of robustness,which are caused by little-labeled data,are restricting the advance and application of BCI,especially for the BCI based on motor imagery(MI).In this paper,we reviewed the recent development in the machine learning algorithm used in the MI-based BCI,which may provide potential solutions for addressing the issue.We classified these algorithms into two categories,namely,and enhancing the representation and expanding the training set.Specifically,these methods of enhancing the representation of features collected from few EEG trials are based on extracting features of multiple bands,regularization,and so on.The methods of expanding the training dataset include approaches of transfer learning(session to session transfer,subject to subject transfer)and generating artificial EEG data.The result of these techniques showed the resolution of the challenges to some extent.As a developing research area,the study of BCI algorithms in little-labeled data is increasingly requiring the advancement of human brain physiological structure research and more transfer learning algorithms research.展开更多
As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine properties.Fractal analysis has been used to characterize the shapes of metal...As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine properties.Fractal analysis has been used to characterize the shapes of metal materials at various scales and dimensions.Conventional methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and interfaces.However,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal materials.From the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear surfaces.The relationship between the fractal dimensions and properties of metal material surfaces and interfaces is summarized.Starting from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be developed.It is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future.展开更多
With the rapid development of wearable electronic skin technology, flexible strain sensors have shown great application prospects in the fields of human motion and physiological signal detection, medical diagnostics, ...With the rapid development of wearable electronic skin technology, flexible strain sensors have shown great application prospects in the fields of human motion and physiological signal detection, medical diagnostics, and human-computer interaction owing to their outstanding sensing performance. This paper reports a strain sensor with synergistic conductive network, consisting of stable carbon nanotube dispersion (CNT) layer and brittle MXene layer by dip-coating and electrostatic self-assembly method, and breathable three-dimensional (3D) flexible substrate of thermoplastic polyurethane (TPU) fibrous membrane prepared through electrospinning technology. The MXene/CNT@PDA-TPU (MC@p-TPU) flexible strain sensor had excellent air permeability, wide operating range (0–450 %), high sensitivity (Gauge Factor, GFmax = 8089.7), ultra-low detection limit (0.05 %), rapid response and recovery times (40 ms/60 ms), and excellent cycle stability and durability (10,000 cycles). Given its superior strain sensing capabilities, this sensor can be applied in physiological signals detection, human motion pattern recognition, and driving exoskeleton robots. In addition, MC@p-TPU fibrous membrane also exhibited excellent photothermal conversion performance and can be used as a wearable photo-heater, which has far-reaching application potential in the photothermal therapy of human joint diseases.展开更多
Background Clinical brain-computer interface(BCI)for mental disorders is an emerging interdisciplinary research field,posing new ethical concerns and challenges,yet lacking practical ethical governance guidelines for ...Background Clinical brain-computer interface(BCI)for mental disorders is an emerging interdisciplinary research field,posing new ethical concerns and challenges,yet lacking practical ethical governance guidelines for stakeholders and the entire community.Aims This study aims to establish a multidisciplinary consensus of principles for ethical governance of clinical BCI research for mental disorders and offer practical ethical guidance to stakeholders involved.Methods A systematic literature review,symposium and roundtable discussions,and a pre-Delphi(round 0)survey were conducted to form the questionnaire for the three-round modified Delphi study.Two rounds of surveys,followed by a third round of independent interviews of 25 experts from BCI-related research domains,were involved.We conducted quantitative analysis of responses and agreements among experts to reveal the consensus and differences regarding the ethical governance of mental BCI research from a multidisciplinary perspective.Results The Delphi panel emphasised important concerns of ethical review practices and ethical principles within the BCI context,identified qualified and highly influential institutions and personnel in conducting and advancing clinical BCI research,and recognised prioritised aspects in the risk-benefit evaluation.Experts expressed diverse opinions on specific ethical concerns,including concerns about invasive technology,its impact on humanity and potential social consequences.Agreement was reached that the practices of ethical governance of clinical BCI for mental disorders should focus on patient voluntariness,autonomy,long-term effects and related assessments of BCI interventions,as well as privacy protection,transparent reporting and ensuring that the research is conducted in qualified institutions with strong data security.Conclusions Ethical governance of clinical research on BCI for mental disorders should include interdisciplinary experts to balance various needs and incorporate the expertise of different stakeholders to avoid serious ethical issues.It requires scientifically grounded approaches,continuous monitoring and interdisciplinary collaboration to ensure evidence-based policies,comprehensive risk assessments and transparency,thereby promoting responsible innovations and protecting patient rights and well-being.展开更多
CeO_(2) based semiconductor are widely used in solar-driven photothermal catalytic dry reforming of methane(DRM)reaction,but still suffer from low activity and low light utilization efficiency.This study developed gra...CeO_(2) based semiconductor are widely used in solar-driven photothermal catalytic dry reforming of methane(DRM)reaction,but still suffer from low activity and low light utilization efficiency.This study developed graphite-CeO_(2) interfaces to enhance solar-driven photothermal catalytic DRM.Compared with carbon nanotubes-modified CeO_(2)(CeO_(2)-CNT),graphite-modified CeO_(2)(CeO_(2)-GRA)constructed graphite-CeO_(2) interfaces with distortion in CeO_(2),leading to the formation abundant oxygen vacancies.These graphite-CeO_(2) interfaces with oxygen vacancies enhanced optical absorption and promoted the generation and separation of photogenerated carriers.The high endothermic capacity of graphite elevated the catalyst surface temperature from 592.1−691.3℃,boosting light-to-thermal conversion.The synergy between photogenerated carriers and localized heat enabled Ni/CeO_(2)-GRA to achieve a CO production rate of 9985.6 mmol/(g·h)(vs 7192.4 mmol/(g·h)for Ni/CeO_(2))and a light-to-fuel efficiency of 21.8%(vs 13.8%for Ni/CeO_(2)).This work provides insights for designing graphite-semiconductor interfaces to advance photothermal catalytic efficiency.展开更多
Active matter encompasses all systems in which each individual constituent independently dissipates energy in its environment.This definition brings together biological systems such as cellular tissues,bacterial colon...Active matter encompasses all systems in which each individual constituent independently dissipates energy in its environment.This definition brings together biological systems such as cellular tissues,bacterial colonies,cytoskeletal filaments driven by molecular motors and animal groups,as well as collections of inert self-propelled particles such as Janus particles,[1]colloidal rollers[2]or vibrated grains.[3]Because of the local persistent drive,these systems are far from thermal equilibrium and cannot be described in terms of thermodynamic potentials.This leads to surprising physics that defies some of the basic intuitions that we have from passive systems,including longrange order in two dimensions[4]and phase-separation in absence of attractive interactions.展开更多
This study investigates the shear mechanical responses and debonding failure mechanisms of anchoring systems comprising three anisotropic media and two anisotropic interfaces under controlled boundary conditions of co...This study investigates the shear mechanical responses and debonding failure mechanisms of anchoring systems comprising three anisotropic media and two anisotropic interfaces under controlled boundary conditions of constant normal load(F_(s)),constant normal stiffness(K),and shear rate(v).A systematic analysis of shear mechanical properties,the evolution of maximum principal strain field,and damage characteristics along shear failure surface is presented.Results from direct shear tests demonstrate that initial shear slip diminishes with increasing F_(s)and K,attributed to the normal constraint strengthening effect,while an increase in v enhances initial shear slip due to attenuated deformation coordination and stress transfer.As F_(s)increases from 7.5 to 120 kN,K from 0 to 12 MPa/mm,and v from 0.1 to 2 mm/min,the peak shear load increases by 210.32%and 80.16%with rising F_(s)and K,respectively,while decreases by 38.57%with increasing v.Correspondingly,the shear modulus exhibits,respectively,a 135.29%and 177.06%increase with rising F_(s)and K,and a 37.03%decrease with larger v.Initial shear dilation is identified as marking the formation of shear failure surface along anisotropic interfaces,resulting from the combined shear actions at the resin bolt interface,where resin undergoes shear by bolt surface protrusions,and the resin-rock interface,where mutual shear occurs between resin and rock.With increasing F_(s)and K and decreasing v,the location of the shear failure surface shifts from the resin-rock interface to the resin-bolt interface,accompanied by a transition in failure mode from tensile rupture of resin to shear off at the resin surface.展开更多
Although the existence of glass–glass interfaces(GGIs)enables improved ductility of metallic nanoglasses(NGs),the excess free volumes at GGIs would cause the NGs to have a much-reduced mechanical strength.Herein,entr...Although the existence of glass–glass interfaces(GGIs)enables improved ductility of metallic nanoglasses(NGs),the excess free volumes at GGIs would cause the NGs to have a much-reduced mechanical strength.Herein,entropy-stabilized GGIs have been in-vestigated in Co–Fe–Ni–Zn–P NGs,which have a large entropy of mixing(1.32R,where R is the gas constant)and could be in a new glass phase,different from that of glassy grain interiors.Through quantitatively determining the activation energy of glass transition sep-arately for the GGIs and glassy grain interiors,the excess free volumes at GGIs are found to be reduced in comparison with those in the glassy grain interiors.The thermodynamically stable GGIs could be associated with increasing entropy of mixing in the GGI regions,which stabilizes the atomic structures of GGIs and enhances the glass forming ability of Co–Fe–Ni–Zn–P NGs.The influences of entropy-stabilized GGIs on the mechanical properties of Co–Fe–Ni–Zn–P NGs are further investigated by nanoindentation and creep tests under tensile deformation,demonstrating that there are notable enhancements in the ductility and mechanical strength for Co–Fe–Ni–Zn–P NGs.This work contributes to an in-depth understanding on the GGI phase in NGs and offers an alternative method for strengthening NGs through GGI engineering.展开更多
Currently,carbon materials derived from biomass are widely sought after as electromagnetic absorbing(EMWA)materials owing to the unique structure,as well as the wide range of natural acquisition pathways,economic viab...Currently,carbon materials derived from biomass are widely sought after as electromagnetic absorbing(EMWA)materials owing to the unique structure,as well as the wide range of natural acquisition pathways,economic viability,and simple processing.However,due to the high dielectric properties,mismatched impedance and single attenuation mechanism,they cannot achieve efficient EMWA performance.Herein,the biomass carbon/Co/porous carbon magnetic composites with a layered gradient structure were fabricated by in-situ deposition of ZIF-67 on the lotus leaf base and then pyrolysis at high temperature.By adjusting the pyrolysis temperature,the sample obtained at 650℃ achieved a minimum reflection value(RLmin)of-34.2dB at a matching thickness of 2.6mm,and a maximum effective absorption bandwidth(EAB)of 7.12GHz.The results indicate that this magnetic composite with a multi-sized layered gradient porous structure has a good electron transport network,a large number of heterogeneous interfaces,and dipole polarization centers,which are conducive to multiple reflection and scattering of microwaves,conduction loss,interface loss,magnetic loss,and impedance matching of materials.Therefore,this work provided a reference for optimizing the EMWA performance of carbon materials and designing a layered gradient porous magnetic composite with multi-sized structure.展开更多
文摘Invasive as well as non-invasive neurotechnologies conceptualized to interface the central and peripheral nervous system have been probed for the past decades,which refer to electroencephalography,electrocorticography and microelectrode arrays.The challenges of these mentioned approaches are characterized by the bandwidth of the spatiotemporal resolution,which in turn is essential for large-area neuron recordings(Abiri et al.,2019).
基金The Open Project of State Key Laboratory of Smart Grid Protection and Operation Control in 2022(No.SGNR0000KJJS2302150).
文摘Fully implanted brain-computer interfaces(BCIs)are preferred as they eliminate signal degradation caused by interference and absorption in external tissues,a common issue in non-fully implanted systems.To optimize the design of electroencephalography electrodes in fully implanted BCI systems,this study investigates the penetration and absorption characteristics of microwave signals in human brain tissue at different frequencies.Electromagnetic simulations are used to analyze the power density distribution and specific absorption rate(SAR)of signals at various frequen-cies.The results indicate that lower-frequency signals offer advantages in terms of power density and attenuation coeffi-cients.However,SAR-normalized analysis,which considers both power density and electromagnetic radiation hazards,shows that higher-frequency signals perform better at superficial to intermediate depths.Specifically,at a depth of 2 mm beneath the cortex,the power density of a 6.5 GHz signal is 247.83%higher than that of a 0.4 GHz signal.At a depth of 5 mm,the power density of a 3.5 GHz signal exceeds that of a 0.4 GHz signal by 224.16%.The findings suggest that 6.5 GHz is optimal for electrodes at a depth of 2 mm,3.5 GHz for 5 mm,2.45 GHz for depths of 15-20 mm,and 1.8 GHz for 25 mm.
文摘In recent years,with the continuous advancement of technolo-gies such as artificial intelligence,neurobiology,and sensors,braincomputer interface(Bcl)technology has embraced opportunitiesfor rapid development The"Guidelines for the Establishment ofNeurological Medical Service Price ltems(Trial)"recently issued bythe National Healthcare Security Administration specifically sets upseparate prospective items for new BCl technologies,which will un-doubtedly strongly facilitate the clinical application of BCl technologyas soon as possible,benefiting a broad range of patients.
基金This work was partially supported by the National Science Foundation(award#1646275)the National Institute of Health(project#R01HD095457).
文摘In this review article, we present more than a decade of our work on the development of brain–computer interface (BCI)systems for the restoration of walking following neurological injuries such as spinal cord injury (SCI) or stroke. Most ofthis work has been in the domain of non-invasive electroencephalogram-based BCIs, including interfacing our system witha virtual reality environment and physical prostheses. Real-time online tests are presented to demonstrate the ability ofable-bodied subjects as well as those with SCI to purposefully operate our BCI system. Extensions of this work are alsopresented and include the development of a portable low-cost BCI suitable for at-home use, our ongoing eforts to develop afully implantable BCI for the restoration of walking and leg sensation after SCI, and our novel BCI-based therapy for strokerehabilitation.
基金supported by the National Natural Science Foundation of China(81600919)the Beijing Nova Program(Z181100006218050).
文摘The development of brain-computer interfaces(BCIs)has established a new communication channel between the brain and external devices for information transmission that requires no muscular signals[1].BCIs have been preliminarily studied to improve motor functions in patients with severe motor disabilities,especially lock-in syndrome.At present,the application of BCIs has been extensively validated.
基金supported by the Ministry of Science and Tech-nology of the People's Republic of China(2021ZD0201900),Project 5(2021ZD0201905).
文摘Brain-computer interface(BCI)technology is rapidly advancing in medical research and application.As an emerging biomedical engineering technology,it has garnered significant attention in the clinical research of brain disease diagnosis and treatment,neurological rehabilitation,and mental health.However,BCI also raises several challenges and ethical concerns in clinical research.In this article,the authors investigate and discuss three aspects of BCI in medicine and healthcare:the state of international ethical governance,multidimensional ethical challenges pertaining to BCI in clinical research,and suggestive concerns for ethical review.Despite the great potential of frontier BCI research and development in the field of medical care,the ethical challenges induced by itself and the complexities of clinical research and brain function have put forward new special fields for ethics in BCI.To ensure"responsible innovation"in BCI research in healthcare and medicine,the creation of an ethical global governance framework and system,along with special guidelines for cutting-edge BCI research in medicine,is suggested.
文摘In this review, five graphical user interfaces(GUIs) used in radiation therapy practices and researches are introduced. They are:(1) the treatment time calculator, superficialx-ray treatment time calculator(SUPCALC) used in the superficial X-ray radiation therapy;(2) the monitor unit calculator, electron monitor unit calculator(EMUC) used in the electron radiation therapy;(3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy(SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy;(4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and(5) the monitor unit calculator, photon beam monitor unit calculator(PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls the multileaf collimator to deliver intensity modulated beams for a specific fluence map used in quality assurance or research. DOSCTP is a treatment planning system using the computed tomography images. Radiation beams(photon or electron) with different energies and field sizes produced by a linear accelerator can be placed in different positions to irradiate the tumour in the patient. DOSCTP is linked to a Monte Carlo simulation engine using the EGSnrc-based code, so that 3D dose distribution canbe determined accurately for radiation therapy. Moreover, DOSCTP can be used for treatment planning of patient or small animal. PMUC is a GUI for calculation of the monitor unit based on the prescription dose of patient in photon beam radiation therapy. The calculation is based on dose corrections in changes of photon beam energy, treatment depth, field size, jaw position, beam axis, treatment distance and beam modifiers. All GUIs mentioned in this review were written either by the Microsoft Visual Basic.net or a MATLAB GUI development tool called GUIDE. In addition, all GUIs were verified and tested using measurements to ensure their accuracies were up to clinical acceptable levels for implementations.
文摘Disorders of consciousness(DoCs) are chronic conditions resulting usually from severe neurological deficits. The limitations of the existing diagnosis systems and methodologies cause a need for additional tools for relevant patients with DoCs assessment, including brain-computer interfaces(BCIs). Recent progress in BCIs' clinical applications may offer important breakthroughs in the diagnosis and therapy of patients with DoCs. Thus the clinical significance of BCI applications in the diagnosis of patients with DoCs is hard to overestimate. One of them may be brain-computer interfaces. The aim of this study is to evaluate possibility of non-invasive EEG-based brain-computer interfaces in diagnosis of patients with DOCs in post-acute and long-term care institutions.
基金financially supported by the National Natural Science Foundation of China(No.52377026 and No.52301192)Taishan Scholars and Young Experts Program of Shandong Province(No.tsqn202103057)+4 种基金Postdoctoral Fellowship Program of CPSF under Grant Number(No.GZB20240327)Shandong Postdoctoral Science Foundation(No.SDCXZG-202400275)Qingdao Postdoctoral Application Research Project(No.QDBSH20240102023)China Postdoctoral Science Foundation(No.2024M751563)the Qingchuang Talents Induction Program of Shandong Higher Education Institution(Research and Innovation Team of Structural-Functional Polymer Composites).
文摘Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly urgent.Multi-component interface engineering is considered an effective means to achieve high-efficiency EMW absorption.However,interface modulation engineering has not been fully discussed and has great potential in the field of EMW absorption.In this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal reduction.By utilizing the different properties of different substances,rich heterogeneous interfaces are constructed.This effectively promotes charge transfer and enhances interfacial polarization and conduction loss.The prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy resin.The minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 GHz.Moreover,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel surfaces.Therefore,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.
基金supported by the National Key R&D Program of China(2021YFF1200602)the National Science Fund for Excellent Overseas Scholars(0401260011)+3 种基金the National Defense Science and Technology Innovation Fund of Chinese Academy of Sciences(c02022088)the Tianjin Science and Technology Program(20JCZDJC00810)the National Natural Science Foundation of China(82202798)the Shanghai Sailing Program(22YF1404200).
文摘Brain-computer interfaces(BCIs)represent an emerging technology that facilitates direct communication between the brain and external devices.In recent years,numerous review articles have explored various aspects of BCIs,including their fundamental principles,technical advancements,and applications in specific domains.However,these reviews often focus on signal processing,hardware development,or limited applications such as motor rehabilitation or communication.This paper aims to offer a comprehensive review of recent electroencephalogram(EEG)-based BCI applications in the medical field across 8 critical areas,encompassing rehabilitation,daily communication,epilepsy,cerebral resuscitation,sleep,neurodegenerative diseases,anesthesiology,and emotion recognition.Moreover,the current challenges and future trends of BCIs were also discussed,including personal privacy and ethical concerns,network security vulnerabilities,safety issues,and biocompatibility.
基金the National Natural Science Foundation of China(Nos.61702395 and 61972302)the Science and Technology Projects of Xi’an,China(No.201809170CX11JC12)。
文摘An electroencephalogram(EEG)signal projection using kernel discriminative locality preserving canonical correlation analysis(KDLPCCA)-based correlation with steady-state visual evoked potential(SSVEP)templates for frequency recognition is presented in this paper.With KDLPCCA,not only a non-linear correlation but also local properties and discriminative information of each class sample are considered to extract temporal and frequency features of SSVEP signals.The new projected EEG features are classified with classical machine learning algorithms,namely,K-nearest neighbors(KNNs),naive Bayes,and random forest classifiers.To demonstrate the effectiveness of the proposed method,16-channel SSVEP data corresponding to 4 frequencies collected from 5 subjects were used to evaluate the performance.Compared with the state of the art canonical correlation analysis(CCA),experimental results show significant improvements in classification accuracy and information transfer rate(ITR),achieving 100%and 240 bits/min with 0.5 s sample block.The superior performance demonstrates that this method holds the promising potential to achieve satisfactory performance for high-accuracy SSVEP-based brain-computer interfaces.
文摘The Brain-Computer Interfaces(BCIs)had been proposed and used in therapeutics for decades.However,the need of time-consuming calibration phase and the lack of robustness,which are caused by little-labeled data,are restricting the advance and application of BCI,especially for the BCI based on motor imagery(MI).In this paper,we reviewed the recent development in the machine learning algorithm used in the MI-based BCI,which may provide potential solutions for addressing the issue.We classified these algorithms into two categories,namely,and enhancing the representation and expanding the training set.Specifically,these methods of enhancing the representation of features collected from few EEG trials are based on extracting features of multiple bands,regularization,and so on.The methods of expanding the training dataset include approaches of transfer learning(session to session transfer,subject to subject transfer)and generating artificial EEG data.The result of these techniques showed the resolution of the challenges to some extent.As a developing research area,the study of BCI algorithms in little-labeled data is increasingly requiring the advancement of human brain physiological structure research and more transfer learning algorithms research.
基金financially supported by the National Key R&D Program of China(No.2022YFE0121300)the National Natural Science Foundation of China(No.52374376)the Introduction Plan for High-end Foreign Experts(No.G2023105001L)。
文摘As a mathematical analysis method,fractal analysis can be used to quantitatively describe irregular shapes with self-similar or self-affine properties.Fractal analysis has been used to characterize the shapes of metal materials at various scales and dimensions.Conventional methods make it difficult to quantitatively describe the relationship between the regular characteristics and properties of metal material surfaces and interfaces.However,fractal analysis can be used to quantitatively describe the shape characteristics of metal materials and to establish the quantitative relationships between the shape characteristics and various properties of metal materials.From the perspective of two-dimensional planes and three-dimensional curved surfaces,this paper reviews the current research status of the fractal analysis of metal precipitate interfaces,metal grain boundary interfaces,metal-deposited film surfaces,metal fracture surfaces,metal machined surfaces,and metal wear surfaces.The relationship between the fractal dimensions and properties of metal material surfaces and interfaces is summarized.Starting from three perspectives of fractal analysis,namely,research scope,image acquisition methods,and calculation methods,this paper identifies the direction of research on fractal analysis of metal material surfaces and interfaces that need to be developed.It is believed that revealing the deep influence mechanism between the fractal dimensions and properties of metal material surfaces and interfaces will be the key research direction of the fractal analysis of metal materials in the future.
基金supported by the National Natural Science Foundation of China(Nos.52373093 and 12072325)the Outstanding Youth Fund of Henan Province(No.242300421062)+1 种基金National Key R&D Program of China(No.2019YFA0706802)the 111 project(No.D18023).
文摘With the rapid development of wearable electronic skin technology, flexible strain sensors have shown great application prospects in the fields of human motion and physiological signal detection, medical diagnostics, and human-computer interaction owing to their outstanding sensing performance. This paper reports a strain sensor with synergistic conductive network, consisting of stable carbon nanotube dispersion (CNT) layer and brittle MXene layer by dip-coating and electrostatic self-assembly method, and breathable three-dimensional (3D) flexible substrate of thermoplastic polyurethane (TPU) fibrous membrane prepared through electrospinning technology. The MXene/CNT@PDA-TPU (MC@p-TPU) flexible strain sensor had excellent air permeability, wide operating range (0–450 %), high sensitivity (Gauge Factor, GFmax = 8089.7), ultra-low detection limit (0.05 %), rapid response and recovery times (40 ms/60 ms), and excellent cycle stability and durability (10,000 cycles). Given its superior strain sensing capabilities, this sensor can be applied in physiological signals detection, human motion pattern recognition, and driving exoskeleton robots. In addition, MC@p-TPU fibrous membrane also exhibited excellent photothermal conversion performance and can be used as a wearable photo-heater, which has far-reaching application potential in the photothermal therapy of human joint diseases.
基金funded by the Shanghai Philosophy and Social Science Planning Project (2021BZX008)the National Social Science Foundation of China (23BZX110)the National Office for Philosophy and Social Science (20&ZD045).
文摘Background Clinical brain-computer interface(BCI)for mental disorders is an emerging interdisciplinary research field,posing new ethical concerns and challenges,yet lacking practical ethical governance guidelines for stakeholders and the entire community.Aims This study aims to establish a multidisciplinary consensus of principles for ethical governance of clinical BCI research for mental disorders and offer practical ethical guidance to stakeholders involved.Methods A systematic literature review,symposium and roundtable discussions,and a pre-Delphi(round 0)survey were conducted to form the questionnaire for the three-round modified Delphi study.Two rounds of surveys,followed by a third round of independent interviews of 25 experts from BCI-related research domains,were involved.We conducted quantitative analysis of responses and agreements among experts to reveal the consensus and differences regarding the ethical governance of mental BCI research from a multidisciplinary perspective.Results The Delphi panel emphasised important concerns of ethical review practices and ethical principles within the BCI context,identified qualified and highly influential institutions and personnel in conducting and advancing clinical BCI research,and recognised prioritised aspects in the risk-benefit evaluation.Experts expressed diverse opinions on specific ethical concerns,including concerns about invasive technology,its impact on humanity and potential social consequences.Agreement was reached that the practices of ethical governance of clinical BCI for mental disorders should focus on patient voluntariness,autonomy,long-term effects and related assessments of BCI interventions,as well as privacy protection,transparent reporting and ensuring that the research is conducted in qualified institutions with strong data security.Conclusions Ethical governance of clinical research on BCI for mental disorders should include interdisciplinary experts to balance various needs and incorporate the expertise of different stakeholders to avoid serious ethical issues.It requires scientifically grounded approaches,continuous monitoring and interdisciplinary collaboration to ensure evidence-based policies,comprehensive risk assessments and transparency,thereby promoting responsible innovations and protecting patient rights and well-being.
文摘CeO_(2) based semiconductor are widely used in solar-driven photothermal catalytic dry reforming of methane(DRM)reaction,but still suffer from low activity and low light utilization efficiency.This study developed graphite-CeO_(2) interfaces to enhance solar-driven photothermal catalytic DRM.Compared with carbon nanotubes-modified CeO_(2)(CeO_(2)-CNT),graphite-modified CeO_(2)(CeO_(2)-GRA)constructed graphite-CeO_(2) interfaces with distortion in CeO_(2),leading to the formation abundant oxygen vacancies.These graphite-CeO_(2) interfaces with oxygen vacancies enhanced optical absorption and promoted the generation and separation of photogenerated carriers.The high endothermic capacity of graphite elevated the catalyst surface temperature from 592.1−691.3℃,boosting light-to-thermal conversion.The synergy between photogenerated carriers and localized heat enabled Ni/CeO_(2)-GRA to achieve a CO production rate of 9985.6 mmol/(g·h)(vs 7192.4 mmol/(g·h)for Ni/CeO_(2))and a light-to-fuel efficiency of 21.8%(vs 13.8%for Ni/CeO_(2)).This work provides insights for designing graphite-semiconductor interfaces to advance photothermal catalytic efficiency.
文摘Active matter encompasses all systems in which each individual constituent independently dissipates energy in its environment.This definition brings together biological systems such as cellular tissues,bacterial colonies,cytoskeletal filaments driven by molecular motors and animal groups,as well as collections of inert self-propelled particles such as Janus particles,[1]colloidal rollers[2]or vibrated grains.[3]Because of the local persistent drive,these systems are far from thermal equilibrium and cannot be described in terms of thermodynamic potentials.This leads to surprising physics that defies some of the basic intuitions that we have from passive systems,including longrange order in two dimensions[4]and phase-separation in absence of attractive interactions.
基金Projects(52174092,42472338,51904290)supported by the National Natural Science Foundation of ChinaProject(BK20220157)supported by the Natural Science Foundation of Jiangsu Province,ChinaProject(2022YCPY0202)supported by the Fundamental Research Funds for the Central Universities,China。
文摘This study investigates the shear mechanical responses and debonding failure mechanisms of anchoring systems comprising three anisotropic media and two anisotropic interfaces under controlled boundary conditions of constant normal load(F_(s)),constant normal stiffness(K),and shear rate(v).A systematic analysis of shear mechanical properties,the evolution of maximum principal strain field,and damage characteristics along shear failure surface is presented.Results from direct shear tests demonstrate that initial shear slip diminishes with increasing F_(s)and K,attributed to the normal constraint strengthening effect,while an increase in v enhances initial shear slip due to attenuated deformation coordination and stress transfer.As F_(s)increases from 7.5 to 120 kN,K from 0 to 12 MPa/mm,and v from 0.1 to 2 mm/min,the peak shear load increases by 210.32%and 80.16%with rising F_(s)and K,respectively,while decreases by 38.57%with increasing v.Correspondingly,the shear modulus exhibits,respectively,a 135.29%and 177.06%increase with rising F_(s)and K,and a 37.03%decrease with larger v.Initial shear dilation is identified as marking the formation of shear failure surface along anisotropic interfaces,resulting from the combined shear actions at the resin bolt interface,where resin undergoes shear by bolt surface protrusions,and the resin-rock interface,where mutual shear occurs between resin and rock.With increasing F_(s)and K and decreasing v,the location of the shear failure surface shifts from the resin-rock interface to the resin-bolt interface,accompanied by a transition in failure mode from tensile rupture of resin to shear off at the resin surface.
基金This work has been endorsed by the Chengdu Guangming Paite Precious Metal Co.,Ltd.,the CDGM Glass Co.,Ltd.,China,and the Research Grants Council of Hong Kong Special Administrative Region,China(No.15233823).
文摘Although the existence of glass–glass interfaces(GGIs)enables improved ductility of metallic nanoglasses(NGs),the excess free volumes at GGIs would cause the NGs to have a much-reduced mechanical strength.Herein,entropy-stabilized GGIs have been in-vestigated in Co–Fe–Ni–Zn–P NGs,which have a large entropy of mixing(1.32R,where R is the gas constant)and could be in a new glass phase,different from that of glassy grain interiors.Through quantitatively determining the activation energy of glass transition sep-arately for the GGIs and glassy grain interiors,the excess free volumes at GGIs are found to be reduced in comparison with those in the glassy grain interiors.The thermodynamically stable GGIs could be associated with increasing entropy of mixing in the GGI regions,which stabilizes the atomic structures of GGIs and enhances the glass forming ability of Co–Fe–Ni–Zn–P NGs.The influences of entropy-stabilized GGIs on the mechanical properties of Co–Fe–Ni–Zn–P NGs are further investigated by nanoindentation and creep tests under tensile deformation,demonstrating that there are notable enhancements in the ductility and mechanical strength for Co–Fe–Ni–Zn–P NGs.This work contributes to an in-depth understanding on the GGI phase in NGs and offers an alternative method for strengthening NGs through GGI engineering.
基金supported by the National Natural Science Foundation of China(Nos.21667019,22066017,and 52173267)the Aviation Science Foundation of China(No.2017ZF56020).
文摘Currently,carbon materials derived from biomass are widely sought after as electromagnetic absorbing(EMWA)materials owing to the unique structure,as well as the wide range of natural acquisition pathways,economic viability,and simple processing.However,due to the high dielectric properties,mismatched impedance and single attenuation mechanism,they cannot achieve efficient EMWA performance.Herein,the biomass carbon/Co/porous carbon magnetic composites with a layered gradient structure were fabricated by in-situ deposition of ZIF-67 on the lotus leaf base and then pyrolysis at high temperature.By adjusting the pyrolysis temperature,the sample obtained at 650℃ achieved a minimum reflection value(RLmin)of-34.2dB at a matching thickness of 2.6mm,and a maximum effective absorption bandwidth(EAB)of 7.12GHz.The results indicate that this magnetic composite with a multi-sized layered gradient porous structure has a good electron transport network,a large number of heterogeneous interfaces,and dipole polarization centers,which are conducive to multiple reflection and scattering of microwaves,conduction loss,interface loss,magnetic loss,and impedance matching of materials.Therefore,this work provided a reference for optimizing the EMWA performance of carbon materials and designing a layered gradient porous magnetic composite with multi-sized structure.
