Adult-born oligodendrocytes are continuously produced in the brains of rodents.The functional role of these cells has been linked to the motor-related activities of healthy animals and is vital for acquiring new motor...Adult-born oligodendrocytes are continuously produced in the brains of rodents.The functional role of these cells has been linked to the motor-related activities of healthy animals and is vital for acquiring new motor skills.However,the relationship between these cells and the control of motor-related activities has not been investigated in pathological conditions.Therefore,the aim of this study is to investigate the role of oligodendrocytes in depression-related motor deficits and the effects of training.Psychomotor retardation is a key symptom of depression.Consistent with the impairments observed in rodent motor performance,the proliferation and activation of adult-born oligodendrocytes are altered in a corticosterone-induced stress paradigm.Therapeutic rotarod training can alleviate these symptoms by reversing the aforementioned changes.Notably,these alterations are particularly pronounced in layer I of the motor cortex.Thus,this study provides evidence of the potential functional involvement of adult-born oligodendrocytes in the motor impairments observed in the depressed animals.Additionally,it offers preliminary results for further investigation into layer I of the motor cortex in relation to these pathological conditions.展开更多
Motor neuron diseases are sporadic or inherited fatal neurodegenerative conditions.They selectively affect the upper and/or lower motor neurons in the brain and spinal cord and feature a slow onset and a subacute cour...Motor neuron diseases are sporadic or inherited fatal neurodegenerative conditions.They selectively affect the upper and/or lower motor neurons in the brain and spinal cord and feature a slow onset and a subacute course contingent upon the site of damage.The main types include amyotrophic lateral sclerosis,progressive muscular atrophy,primary lateral sclerosis,and progressive bulbar palsy,the pathological processes of which are largely identical,with the main disparity lying in the location of the lesions.Amyotrophic lateral sclerosis is the representative condition in this group of diseases,while other types are its variants.Hence,this article mainly focuses on the advancements and challenges in drug research for amyotrophic lateral sclerosis but also briefly addresses several other important degenerative motor neuron diseases.Although the precise pathogenesis remains elusive,recent advancements have shed light on various theories,including gene mutation,excitatory amino acid toxicity,autoimmunology,and neurotrophic factors.The US Food and Drug Administration has approved four drugs for use in delaying the progression of amyotrophic lateral sclerosis:riluzole,edaravone,AMX0035,and tofersen,with the latter being the most recent to receive approval.However,following several phaseⅢtrials that failed to yield favorable outcomes,AMX0035 has been voluntarily withdrawn from both the US and Canadian markets.This article presents a comprehensive summary of drug trials primarily completed between January 1,2023,and June 30,2024,based on data sourced from clinicaltrials.gov.Among these trials,five are currently in phaseⅠ,seventeen are in phaseⅡ,and eleven are undergoing phaseⅢevaluation.Notably,24 clinical trials are now investigating potential disease-modifying therapy drugs,accounting for the majority of the drugs included in this review.Some promising drugs being investigated in preclinical studies,such as ATH-1105,are included in our analysis,and another review in frontiers in gene therapy and immunotherapy has demonstrated their therapeutic potential for motor neuron diseases.This article was written to be an overview of research trends and treatment prospects related to motor neuron disease drugs,with the aim of highlighting the latest potentialities for clinical therapy.展开更多
Purpose:This study examined potential differences in strength,muscle morphology,and motor unit(MU)behavior of the abductor digiti minimi(ADM)between normal-fat(NF)and over-fat(OF)males.Methods:Dual-energy X-ray absorp...Purpose:This study examined potential differences in strength,muscle morphology,and motor unit(MU)behavior of the abductor digiti minimi(ADM)between normal-fat(NF)and over-fat(OF)males.Methods:Dual-energy X-ray absorptiometry assessed percent body fat(%BF).Ultrasonography determined muscle cross-sectional area(CSA),echo intensity(EI),and subcutaneous fat(s FAT).MU behavior was assessed during isometric muscle actions at 50%of maximal voluntary contraction(MVC)by analyzing the y-intercepts and slopes for the MU action potential amplitude(MUAPAMP)vs.recruitment threshold(RT)relationships,the A and B terms for the mean firing rate(MFR)vs.RT relationships,and normalized electromyographic amplitude(N-EMGRMS).MU firing times and waveforms were validated with reconstruct-and-test and spike trigger average procedures.Results:%BF was greater for OF(25.70%±5.40%)than NF(16.50%±2.20%;p<0.001).MVC was greater for NF(27.13±7.16)N than OF([19.89±4.96]N;p=0.014).CSA was greater for NF(2.48±0.39)cm^(2)than OF([1.95±0.47]cm^(2);p=0.011).The y-intercepts for the MUAPAMPvs.RT relationships were greater for NF(0.283±0.254)m V than OF([-0.221±0.659]m V;p=0.004).The B terms for the MFR vs.RT relationships were greater for NF(-0.024±0.003)pps/%MVC than OF([-0.031±0.009]pps/%MVC;p=0.038).N-EMGRMSwas similar between groups(p=0.463).Conclusion:Maximal strength,muscle size,and MU recruitment and firing rate patterns for a non-weight bearing muscle differed between normal-fat and over-fat males.展开更多
To explore the distribution law of the temperature field in the motor pump and the influence of the fanshaped DC channel with spoiler in the pump housing on its heat dissipation performance.This study takes the arc-ge...To explore the distribution law of the temperature field in the motor pump and the influence of the fanshaped DC channel with spoiler in the pump housing on its heat dissipation performance.This study takes the arc-gear type hydraulicmotor pump as the research object.In COMSOL,a coupled heat transfer simulationmodel of themotor pump’s fluid-solid coupling is established,and the internal temperature field characteristics are analyzed.To improve the heat dissipation effect of the motor pump,it is proposed to arrange spoiler in the fan-shaped DC channel of the pump housing to enhance heat dissipation.Three types of spoilers,namely,wing-shaped,inclined rectangle-shaped,and wave-shaped,are designed.The simulation results show that when the motor pump operates under rated conditions,due to the poor heat dissipation environment inside the motor pump,the high-temperature areas of the motor pump are concentrated in the rotor and permanent magnet parts.After arranging the spoiler,the turbulent kinetic energy and vorticity in the fan-shaped DC channel of the pump housing are significantly enhanced.All three spoiler structures can reduce the maximum temperature of each component of the motor.According to the comprehensive performance evaluation criterion(PEC),the inclined rectangle-shaped structure has the best comprehensive heat transfer performance(PEC=1.114),while the wave-shaped structure has higher heat transfer efficiency but greater pressure loss.The wing-shaped structure has relatively limited enhancement effect on heat dissipation.This study systematically quantifies the influence of different spoiler structures on heat dissipation performance and flowresistance characteristics,providing a solution for enhancing the heat dissipation of the motor pump.展开更多
The increasing global prevalence of mild cognitive impairment(MCI)necessitates a paradigm shift in early detection strategies.Conventional neuropsychological assessment methods,predominantly paper-and-pencil tests suc...The increasing global prevalence of mild cognitive impairment(MCI)necessitates a paradigm shift in early detection strategies.Conventional neuropsychological assessment methods,predominantly paper-and-pencil tests such as the Mini-Mental State Examination and the Montreal Cognitive Assessment,exhibit inherent limitations with respect to accessibility,administration burden,and sensitivity to subtle cognitive decline,particularly among diverse populations.This commentary critically examines a recent study that champions a novel approach:The integration of gait and handwriting kinematic parameters analyzed via machine learning for MCI screening.The present study positions itself within the broader landscape of MCI detection,with a view to comparing its advantages against established neuropsychological batteries,advanced neuroimaging(e.g.,positron emission tomography,magnetic resonance imaging),and emerging fluid biomarkers(e.g.,cerebrospinal fluid,blood-based assays).While the study demonstrates promising accuracy(74.44%area under the curve 0.74 with gait and graphic handwriting)and addresses key unmet needs in accessibility and objectivity,we highlight its cross-sectional nature,limited sample diversity,and lack of dual-task assessment as areas for future refinement.This commentary posits that kinematic biomarkers offer a distinctive,scalable,and ecologically valid approach to widespread MCI screening,thereby complementing existing methods by providing real-world functional insights.Future research should prioritize longitudinal validation,expansion to diverse cohorts,integration with multimodal data including dual-tasking,and the development of highly portable,artificial intelligence-driven solutions to achieve the democratization of early MCI detection and enable timely interventions.展开更多
A surface pyrolysis and gas-phase combustion of the Ammonium Perchlorate(AP)/Hydroxy Terminated Polybutadiene(HTPB)composite propellant reaction kinetic mechanism with five-step chemical reaction is adopted.The effect...A surface pyrolysis and gas-phase combustion of the Ammonium Perchlorate(AP)/Hydroxy Terminated Polybutadiene(HTPB)composite propellant reaction kinetic mechanism with five-step chemical reaction is adopted.The effects of helium injection on the burning rate and combustion of AP/HTPB propellant are analyzed in details,and the characteristics of motor performance are obtained.The numerical simulation results demonstrate that helium injection enhances the combustion chamber pressure,thereby increasing the burning rate of propellant.However,the primary combustion reaction of the AP/HTPB propellant takes place within a thin layer on the burning surface,so the low-temperature helium has minimal impact on the gasphase combustion.Ultimately,the helium not only elevates the nozzle exit velocity,resulting in specific impulse gain,but also reduces the exhaust plume temperature.With an increase of helium mass flow rate,the area of the velocity increase zone at the nozzle exit continuously decreases,but the average velocity in the motor exit continuously increases.Overall,when the helium flow rate is 2.5 kg/s,the specific impulse can reach 10.5%.Reducing the helium injection hole diameter enhances mixing of helium and combustion gas and expands the velocity increase zone,thereby maximizing the exit velocity gain in average velocity at the nozzle exit.When the injection hole diameter is reduced from 100 mm to 20 mm,the specific impulse gain increases from 3.1%to 10.6%.Furthermore,increasing helium injection temperature greatly boosts the velocity of the mixed gas with the same helium mass fraction ultimately improving specific impulse.展开更多
Motor imbalance is a critical failure mode in rotating machinery,potentially causing severe equipment damage if undetected.Traditional vibration-based diagnostic methods rely on direct sensor contact,leading to instal...Motor imbalance is a critical failure mode in rotating machinery,potentially causing severe equipment damage if undetected.Traditional vibration-based diagnostic methods rely on direct sensor contact,leading to installation challenges and measurement artifacts that can compromise accuracy.This study presents a novel radar-based framework for non-contact motor imbalance detection using 24 GHz continuous-wave radar.A dataset of 1802 experimental trials was sourced,covering four imbalance levels(0,10,20,30 g)across varying motor speeds(500–1500 rpm)and load torques(0–3 Nm).Dual-channel in-phase and quadrature radar signals were captured at 10,000 samples per second for 30-s intervals,preserving both amplitude and phase information for analysis.A multi-domain feature extraction methodology captured imbalance signatures in time,frequency,and complex signal domains.From 65 initial features,statistical analysis using Kruskal–Wallis tests identified significant descriptors,and recursive feature elimination with Random Forest reduced the feature set to 20 dimensions,achieving 69%dimensionality reduction without loss of performance.Six machine learning algorithms,Random Forest,Extra Trees Classifier,Extreme Gradient Boosting,Categorical Boosting,Support Vector Machine with radial basis function kernel,and k-Nearest Neighbors were evaluated with grid-search hyperparameter optimization and five-fold cross-validation.The Extra Trees Classifier achieved the best performance with 98.52%test accuracy,98%cross-validation accuracy,and minimal variance,maintaining per-class precision and recall above 97%.Its superior performance is attributed to its randomized split selection and full bootstrapping strategy,which reduce variance and overfitting while effectively capturing the nonlinear feature interactions and non-normal distributions present in the dataset.The model’s average inference time of 70 ms enables near real-time deployment.Comparative analysis demonstrates that the radar-based framework matches or exceeds traditional contact-based methods while eliminating their inherent limitations,providing a robust,scalable,and noninvasive solution for industrial motor condition monitoring,particularly in hazardous or space-constrained environments.展开更多
The development of brain-computer interfaces(BCI)based on motor imagery(MI)has greatly improved patients’quality of life with movement disorders.The classification of upper limb MI has been widely studied and applied...The development of brain-computer interfaces(BCI)based on motor imagery(MI)has greatly improved patients’quality of life with movement disorders.The classification of upper limb MI has been widely studied and applied in many fields,including rehabilitation.However,the physiological representations of left and right lower limb movements are too close and activated deep in the cerebral cortex,making it difficult to distinguish their features.Therefore,classifying lower limbs motor imagery is more challenging.In this study,we propose a feature extraction method based on functional connectivity,which utilizes phase-locked values to construct a functional connectivity matrix as the features of the left and right legs,which can effectively avoid the problem of physiological representations of the left and right lower limbs being too close to each other during movement.In addition,considering the topology and the temporal characteristics of the electroencephalogram(EEG),we designed a temporal-spatial convolutional network(TSGCN)to capture the spatiotemporal information for classification.Experimental results show that the accuracy of the proposed method is higher than that of existing methods,achieving an average classification accuracy of 73.58%on the internal dataset.Finally,this study explains the network mechanism of left and right foot MI from the perspective of graph theoretic features and demonstrates the feasibility of decoding lower limb MI.展开更多
Nonhuman primates are increasingly being used as animal models in neuroscience research.However,efficient neuronal tracing techniques for labeling motor neurons and primary sensory afferents in the monkey spinal cord ...Nonhuman primates are increasingly being used as animal models in neuroscience research.However,efficient neuronal tracing techniques for labeling motor neurons and primary sensory afferents in the monkey spinal cord are lacking.Here,by injecting the cholera toxin B subunit into the sciatic nerve of a rhesus monkey,we successfully labeled the motor neurons and primary sensory afferents in the lumbar and sacralspinal cord.Labeled alpha motor neurons were located in lamina IX of the L6–S1 segments,which innervate both flexors and extensors.The labeled primary sensory afferents were mainly myelinated Aβfibers that terminated mostly in laminae I and II of the L4–L7 segments.Together with the labeled proprioceptive afferents,the primary sensory afferents formed excitatory synapses with multiple types of spinal neurons.In summary,our methods successfully traced neuronal connections in the monkey spinal cord and can be used in spinal cord studies when nonhuman primates are used.展开更多
Spinal cord injury(SCI)interrupts the flow of information between the brain and the spinal cord,thus leading to a loss of sensory information and motor paralysis of the body below the lesion.Surprisingly,most SCIs are...Spinal cord injury(SCI)interrupts the flow of information between the brain and the spinal cord,thus leading to a loss of sensory information and motor paralysis of the body below the lesion.Surprisingly,most SCIs are incomplete and spare supraspinal pathways,especially those located within the peripheral white matter of the spinal cord,which includes reticulospinal pathways originating from the medullary reticular formation.Whereas there is abundant literature about the motor cortex,its corticospinal pathway,and its capacity to modulate functional recovery after SCI,less is known about the medullary reticular formation and its reticulospinal pathway.展开更多
Automated detection of Motor Imagery(MI)tasks is extremely useful for prosthetic arms and legs of stroke patients for their rehabilitation.Prediction of MI tasks can be performed with the help of Electroencephalogram(...Automated detection of Motor Imagery(MI)tasks is extremely useful for prosthetic arms and legs of stroke patients for their rehabilitation.Prediction of MI tasks can be performed with the help of Electroencephalogram(EEG)signals recorded by placing electrodes on the scalp of subjects;however,accurate prediction of MI tasks remains a challenge due to noise that is incurred during the EEG signal recording process,the extraction of a feature vector with high interclass variance,and accurate classification.The proposed method consists of preprocessing,feature extraction,and classification.First,EEG signals are denoised using a bandpass filter followed by Independent Component Analysis(ICA).Multiple channels are combined to form a single surrogate channel.Short Time Fourier Transform(STFT)is then applied to convert time domain EEG signals into the frequency domain.Handcrafted and automated features are extracted from EEG signals and then concatenated to form a single feature vector.We propose a customized two-dimensional Convolutional Neural Network(CNN)for automated feature extraction with high interclass variance.Feature selection is performed using Particle Swarm Optimization(PSO)to obtain optimal features.The final feature vector is passed to three different classifiers:Support Vector Machine(SVM),Random Forest(RF),and Long Short-Term Memory(LSTM).The final decision is made using the Model-Agnostic Meta Learning(MAML).The Proposed method has been tested on two datasets,including PhysioNet and BCI Competition IV-2a,and it achieved better results in terms of accuracy and F1 score than existing state-of-the-art methods.The proposed framework achieved an accuracy and F1 score of 96%on the PhysioNet dataset and 95.5%on the BCI Competition IV,dataset 2a.We also present SHapley Additive exPlanations(SHAP)and Gradient-weighted Class Activation Mapping(Grad-CAM)explainable techniques to enhance model interpretability in a clinical setting.展开更多
The arc-linear motor(ALM) is a new type of special motor derived from the linear motor, which has the merits of high torque, compact structure and fast dynamic response. This kind of motor does not need a complex inte...The arc-linear motor(ALM) is a new type of special motor derived from the linear motor, which has the merits of high torque, compact structure and fast dynamic response. This kind of motor does not need a complex intermediate transmission device, it is used in some direct-drive applications for continuous rotation or limited angle motion. However, there is no systematic summary and generalization of the ALMs so far.Therefore, this paper systematically overviews the recent advances in ALMs for direct-drive systems. First, the evolution process and basic structure of the ALM are introduced. And then, various ALMs are reviewed with particular reference to motor topologies, working principle, motor performance,optimization design and control techniques. To heel, a comprehensive comparison of several typical ALMs is carried out. Finally, the application areas, main challenges and development trends of the ALMs are highlighted.展开更多
Dear Editor,The primary motor cortex,also known as MOp in rodents,F1,or M1 in primates[1],plays a crucial role in autonomous motor control.It is interconnected with other motor control structures such as the basal gan...Dear Editor,The primary motor cortex,also known as MOp in rodents,F1,or M1 in primates[1],plays a crucial role in autonomous motor control.It is interconnected with other motor control structures such as the basal ganglia,thalamus,and brainstem.Among these connections,the corticostriatal system plays a significant role in functions including action selection,motor control,sequence learning,and habit formation[2].展开更多
Switched Reluctance Motors(SRMs),outfitted with rugged construction,good speed range,high torque density,and rare earth-free nature that outweigh induction motors(IM)and permanent magnet synchronous motor(PMSM),afford...Switched Reluctance Motors(SRMs),outfitted with rugged construction,good speed range,high torque density,and rare earth-free nature that outweigh induction motors(IM)and permanent magnet synchronous motor(PMSM),afford a broad range of applications in the domain of electric vehicles(EVs).Standard copper magnetic wire and low-carbon steel laminations are used to construct SRMs,which give them high efficiency in the range of 85-95%.Despite SRM's desirable features over traditional motor-speed drives,high torque ripples and radial distortions constrain their deployment in EVs.Precise rotor position is imperative for effective management of the speed and torque of SRMs.This paper provides an illustrative compendium on review of the torque-speed control and ripple mitigation techniques using design enhancements and control methods for SRM drives for EV applications.The various schemes were evaluated on their performance metricsoperational speed range,control complexity,practical realization,need for pre-stored parameters(look-up tables of current,inductance and torque profiles)and motor controller memory requirements.The findings provide valuable insights into balancing the gains and trade-offs associated with EV applications.Furthermore,they pinpoint opportunities for enhancement by analyzing the cost and technical aspects of different SRM controllers.展开更多
The hyperloop idea,which is one of the most ecofriendly,low-carbon emissions,and fossil fuel-efficient modes of transportation,has recently become quite popular.In this study,a double-sided linear induction motor(LIM)...The hyperloop idea,which is one of the most ecofriendly,low-carbon emissions,and fossil fuel-efficient modes of transportation,has recently become quite popular.In this study,a double-sided linear induction motor(LIM)with 500 W of output power,60 N of thrust force and 200 V/38.58 Hz of supply voltage was designed to be used in hyperloop development competition hosted by the scientific and technological research council of turkey(TüB?TAK)rail transportation technologies institute(RUTE).In contrast to the studies in the literature,concentrated winding is preferred instead of distributed winding due to mechanical constraints.The electromagnetic design of LIM,whose mechanical and electrical requirements were determined considering the hyperloop development competition,was carried out by following certain steps.Then,the designed model was simulated and analyzed by finite element method(FEM),and the necessary optimizations have been performed to improve the motor characteristics.By examining the final model,the applicability of the concentrated winding type LIM for hyperloop technology has been investigated.Besides,the effects of primary material,railway material,and mechanical air-gap length on LIM performance were also investigated.In the practical phase of the study,the designed LIM has been prototyped and tested.The validation of the experimental results was achieved through good agreement with the finite element analysis results.展开更多
Light-driven artificial molecular machines[1,2]are a class of functional small molecules powered by photochemical reactions,broadly divided into molecular motors and molecular photoswitches.Molecular motors[3,4],owing...Light-driven artificial molecular machines[1,2]are a class of functional small molecules powered by photochemical reactions,broadly divided into molecular motors and molecular photoswitches.Molecular motors[3,4],owing to their intrinsic point chirality and dynamic axial chirality,undergo unidirectional rotation about a carbon–carbon double bond when irradiated with light.In nature,biological molecular motors and pumps are ubiquitous:driving vision,intracellular transport,energy conversion,signal transduction,muscle contraction,and locomotion.展开更多
Background:Acupuncture is widely used in modulating brain excitability and motor function,as a form of complementary and alternative medicine.However,there is no existing meta-analysis evaluating the effectiveness and...Background:Acupuncture is widely used in modulating brain excitability and motor function,as a form of complementary and alternative medicine.However,there is no existing meta-analysis evaluating the effectiveness and safety of acupuncture on corticospinal excitability(CSE),and the credibility of the evidence has yet to be quantified.Objective:This study was designed to assess the efficacy and safety of electroacupuncture(EA)and manual acupuncture(MA)in enhancing brain excitability,specifically focusing on CSE as measured by transcranial magnetic stimulation(TMS).Search strategy:This study followed a systematic approach,searching 9 databases up to August 2024 and examining grey literature,in compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Inclusion criteria:Studies were included if they compared the clinical efficacy of EA or MA with sham acupuncture,no treatment or usual training.Data extraction and analysis:Three investigators independently conducted literature screening,data extraction,and risk of bias assessment.The primary outcome focused on motor-evoked potentials as measured by TMS,with treatment effects quantified using mean differences or standardized mean differences between pre-and post-treatment.Subgroup analyses were conducted using mixed-effects models,while random-effects or fixed-effects models were used to estimate average treatment differences across studies.Results:Based on 34 studies involving 1031 adults,acupuncture techniques significantly enhanced CSE.EA had a greater impact than MA,with effect sizes of 0.53 mV vs 0.43 mV(95%confidence interval[CI]:[0.30,0.76],P<0.00001 vs 95%CI:[0.28,0.59],P<0.00001).The 5 most frequently used acupoints were LI4(Hegu,32 times),ST36(Zusanli,10 times),LI11(Quchi,7 times),TE5(Waiguan,6 times),and GB34(Yanglingquan,5 times).Conclusion:This systematic review indicates that both EA and MA could effectively and safely enhance CSE,bringing the corticospinal pathway closer to the threshold for firing,which may ultimately improve motor function.LI4,ST36,LI11,TE5 and GB34 are the most commonly used acupoints.展开更多
Pyrrolizidine alkaloids(PAs)are natural toxins generated as secondarymetabolites in plants,predominantly consisting of unsaturated PAs with diverse toxicities,such as hepatotoxicity.Echimidine,a prominent PA,is believ...Pyrrolizidine alkaloids(PAs)are natural toxins generated as secondarymetabolites in plants,predominantly consisting of unsaturated PAs with diverse toxicities,such as hepatotoxicity.Echimidine,a prominent PA,is believed to exert various toxicological effects,including survival inhibition and induction of apoptosis of hepatocytes.However,the effects of echimidine on development remain unclear.We selected three concentrations of 0.02,0.2,and 2 mg/L to investigate the developmental toxicity of echimidine on zebrafish embryos.After a 7-day exposure,we observed hyperactivity and anxiety-like behavior in zebrafish larvae.Furthermore,we found that echimidine exposure significantly promoted embryonic motor neurodevelopment in geneticallymodified zebrafish.Next,we detected that echimidine exposure significantly increased the content of the excitatory neurotransmitter acetylcholine(ACh),accompanied by a significant decrease in acetylcholinesterase(AChE)activity.Conversely,echimidine led to a significant reduction in the content of the sedative neurotransmitterγ-aminobutyric acid(GABA),accompanied by abnormal gene expression of enzymes related to GABA synthesis.Moreover,we elucidated the strong direct binding of echimidine to zebrafish and human AChE protein through molecular docking.In summary,our study found that echimidine induced ACh accumulation possibly by inhibiting AChE activity,leading to motor neurodevelopmental abnormalities and hyperactivity in zebrafish larvae.This work provides important scientific knowledge on the effects and mechanisms of PAs on neural development,which is helpful for controlling the risk of PAs in food and protecting public health.展开更多
Reach-to-grasp movements require integrating information on both object location and grip type,but how these elements are planned and to what extent they interact remains unclear.We designed a new experimental paradig...Reach-to-grasp movements require integrating information on both object location and grip type,but how these elements are planned and to what extent they interact remains unclear.We designed a new experimental paradigm in which monkeys sequentially received reach and grasp cues with delays,requiring them to retain and integrate both cues to grasp the goal object with appropriate hand gestures.Neural activity in the dorsal premotor cortex(PMd)revealed that reach and grasp were similarly represented yet not independent.Upon receiving the second cue,the PMd continued encoding the first,but over half of the neurons displayed incongruent modulations:enhanced,attenuated,or even reversed.Population-level analysis showed significant changes in encoding structure,forming distinct neural patterns.Leveraging canonical correlation analysis,we identified a shared subspace preserving the initial cue’s encoding,contributed by both congruent and incongruent neurons.Together,these findings reveal a novel perspective on the interactive planning of reach and grasp within the PMd,providing insights into potential applications for brain–machine interfaces.展开更多
基金supported by Hong Kong Health and Medical Research Fund,No.02133206(to KFS).
文摘Adult-born oligodendrocytes are continuously produced in the brains of rodents.The functional role of these cells has been linked to the motor-related activities of healthy animals and is vital for acquiring new motor skills.However,the relationship between these cells and the control of motor-related activities has not been investigated in pathological conditions.Therefore,the aim of this study is to investigate the role of oligodendrocytes in depression-related motor deficits and the effects of training.Psychomotor retardation is a key symptom of depression.Consistent with the impairments observed in rodent motor performance,the proliferation and activation of adult-born oligodendrocytes are altered in a corticosterone-induced stress paradigm.Therapeutic rotarod training can alleviate these symptoms by reversing the aforementioned changes.Notably,these alterations are particularly pronounced in layer I of the motor cortex.Thus,this study provides evidence of the potential functional involvement of adult-born oligodendrocytes in the motor impairments observed in the depressed animals.Additionally,it offers preliminary results for further investigation into layer I of the motor cortex in relation to these pathological conditions.
基金supported by the National Key Research and Development Program of China,No.2022YFC2703101(to YC)the National Natural Science Fundation of China,No.82371422(to YC)+1 种基金the National Innovation and Entrepreneurship Training Program for College Students,No.202310611408(to XW)the 1·3·5 Project for Disciplines of Excellence Clinical Research Fund,West China Hospital,Sichuan University,No.2023HXFH032(to YC)。
文摘Motor neuron diseases are sporadic or inherited fatal neurodegenerative conditions.They selectively affect the upper and/or lower motor neurons in the brain and spinal cord and feature a slow onset and a subacute course contingent upon the site of damage.The main types include amyotrophic lateral sclerosis,progressive muscular atrophy,primary lateral sclerosis,and progressive bulbar palsy,the pathological processes of which are largely identical,with the main disparity lying in the location of the lesions.Amyotrophic lateral sclerosis is the representative condition in this group of diseases,while other types are its variants.Hence,this article mainly focuses on the advancements and challenges in drug research for amyotrophic lateral sclerosis but also briefly addresses several other important degenerative motor neuron diseases.Although the precise pathogenesis remains elusive,recent advancements have shed light on various theories,including gene mutation,excitatory amino acid toxicity,autoimmunology,and neurotrophic factors.The US Food and Drug Administration has approved four drugs for use in delaying the progression of amyotrophic lateral sclerosis:riluzole,edaravone,AMX0035,and tofersen,with the latter being the most recent to receive approval.However,following several phaseⅢtrials that failed to yield favorable outcomes,AMX0035 has been voluntarily withdrawn from both the US and Canadian markets.This article presents a comprehensive summary of drug trials primarily completed between January 1,2023,and June 30,2024,based on data sourced from clinicaltrials.gov.Among these trials,five are currently in phaseⅠ,seventeen are in phaseⅡ,and eleven are undergoing phaseⅢevaluation.Notably,24 clinical trials are now investigating potential disease-modifying therapy drugs,accounting for the majority of the drugs included in this review.Some promising drugs being investigated in preclinical studies,such as ATH-1105,are included in our analysis,and another review in frontiers in gene therapy and immunotherapy has demonstrated their therapeutic potential for motor neuron diseases.This article was written to be an overview of research trends and treatment prospects related to motor neuron disease drugs,with the aim of highlighting the latest potentialities for clinical therapy.
文摘Purpose:This study examined potential differences in strength,muscle morphology,and motor unit(MU)behavior of the abductor digiti minimi(ADM)between normal-fat(NF)and over-fat(OF)males.Methods:Dual-energy X-ray absorptiometry assessed percent body fat(%BF).Ultrasonography determined muscle cross-sectional area(CSA),echo intensity(EI),and subcutaneous fat(s FAT).MU behavior was assessed during isometric muscle actions at 50%of maximal voluntary contraction(MVC)by analyzing the y-intercepts and slopes for the MU action potential amplitude(MUAPAMP)vs.recruitment threshold(RT)relationships,the A and B terms for the mean firing rate(MFR)vs.RT relationships,and normalized electromyographic amplitude(N-EMGRMS).MU firing times and waveforms were validated with reconstruct-and-test and spike trigger average procedures.Results:%BF was greater for OF(25.70%±5.40%)than NF(16.50%±2.20%;p<0.001).MVC was greater for NF(27.13±7.16)N than OF([19.89±4.96]N;p=0.014).CSA was greater for NF(2.48±0.39)cm^(2)than OF([1.95±0.47]cm^(2);p=0.011).The y-intercepts for the MUAPAMPvs.RT relationships were greater for NF(0.283±0.254)m V than OF([-0.221±0.659]m V;p=0.004).The B terms for the MFR vs.RT relationships were greater for NF(-0.024±0.003)pps/%MVC than OF([-0.031±0.009]pps/%MVC;p=0.038).N-EMGRMSwas similar between groups(p=0.463).Conclusion:Maximal strength,muscle size,and MU recruitment and firing rate patterns for a non-weight bearing muscle differed between normal-fat and over-fat males.
基金supported by the Henan Provincial Key Research and Development Special Project(251111220200)Natural Science Foundation of Henan Province Project(252300420446).
文摘To explore the distribution law of the temperature field in the motor pump and the influence of the fanshaped DC channel with spoiler in the pump housing on its heat dissipation performance.This study takes the arc-gear type hydraulicmotor pump as the research object.In COMSOL,a coupled heat transfer simulationmodel of themotor pump’s fluid-solid coupling is established,and the internal temperature field characteristics are analyzed.To improve the heat dissipation effect of the motor pump,it is proposed to arrange spoiler in the fan-shaped DC channel of the pump housing to enhance heat dissipation.Three types of spoilers,namely,wing-shaped,inclined rectangle-shaped,and wave-shaped,are designed.The simulation results show that when the motor pump operates under rated conditions,due to the poor heat dissipation environment inside the motor pump,the high-temperature areas of the motor pump are concentrated in the rotor and permanent magnet parts.After arranging the spoiler,the turbulent kinetic energy and vorticity in the fan-shaped DC channel of the pump housing are significantly enhanced.All three spoiler structures can reduce the maximum temperature of each component of the motor.According to the comprehensive performance evaluation criterion(PEC),the inclined rectangle-shaped structure has the best comprehensive heat transfer performance(PEC=1.114),while the wave-shaped structure has higher heat transfer efficiency but greater pressure loss.The wing-shaped structure has relatively limited enhancement effect on heat dissipation.This study systematically quantifies the influence of different spoiler structures on heat dissipation performance and flowresistance characteristics,providing a solution for enhancing the heat dissipation of the motor pump.
文摘The increasing global prevalence of mild cognitive impairment(MCI)necessitates a paradigm shift in early detection strategies.Conventional neuropsychological assessment methods,predominantly paper-and-pencil tests such as the Mini-Mental State Examination and the Montreal Cognitive Assessment,exhibit inherent limitations with respect to accessibility,administration burden,and sensitivity to subtle cognitive decline,particularly among diverse populations.This commentary critically examines a recent study that champions a novel approach:The integration of gait and handwriting kinematic parameters analyzed via machine learning for MCI screening.The present study positions itself within the broader landscape of MCI detection,with a view to comparing its advantages against established neuropsychological batteries,advanced neuroimaging(e.g.,positron emission tomography,magnetic resonance imaging),and emerging fluid biomarkers(e.g.,cerebrospinal fluid,blood-based assays).While the study demonstrates promising accuracy(74.44%area under the curve 0.74 with gait and graphic handwriting)and addresses key unmet needs in accessibility and objectivity,we highlight its cross-sectional nature,limited sample diversity,and lack of dual-task assessment as areas for future refinement.This commentary posits that kinematic biomarkers offer a distinctive,scalable,and ecologically valid approach to widespread MCI screening,thereby complementing existing methods by providing real-world functional insights.Future research should prioritize longitudinal validation,expansion to diverse cohorts,integration with multimodal data including dual-tasking,and the development of highly portable,artificial intelligence-driven solutions to achieve the democratization of early MCI detection and enable timely interventions.
基金co-supported by the Fundamental Research Funds for Central Universities,China(No.3072024XX0206)the Natural Science Foundation of Heilongjiang Province,China(No.LH2024E069)。
文摘A surface pyrolysis and gas-phase combustion of the Ammonium Perchlorate(AP)/Hydroxy Terminated Polybutadiene(HTPB)composite propellant reaction kinetic mechanism with five-step chemical reaction is adopted.The effects of helium injection on the burning rate and combustion of AP/HTPB propellant are analyzed in details,and the characteristics of motor performance are obtained.The numerical simulation results demonstrate that helium injection enhances the combustion chamber pressure,thereby increasing the burning rate of propellant.However,the primary combustion reaction of the AP/HTPB propellant takes place within a thin layer on the burning surface,so the low-temperature helium has minimal impact on the gasphase combustion.Ultimately,the helium not only elevates the nozzle exit velocity,resulting in specific impulse gain,but also reduces the exhaust plume temperature.With an increase of helium mass flow rate,the area of the velocity increase zone at the nozzle exit continuously decreases,but the average velocity in the motor exit continuously increases.Overall,when the helium flow rate is 2.5 kg/s,the specific impulse can reach 10.5%.Reducing the helium injection hole diameter enhances mixing of helium and combustion gas and expands the velocity increase zone,thereby maximizing the exit velocity gain in average velocity at the nozzle exit.When the injection hole diameter is reduced from 100 mm to 20 mm,the specific impulse gain increases from 3.1%to 10.6%.Furthermore,increasing helium injection temperature greatly boosts the velocity of the mixed gas with the same helium mass fraction ultimately improving specific impulse.
基金funded by Princess Nourah bint Abdulrahman University Researchers Support-ing Project number(PNURSP2026R346)Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia.
文摘Motor imbalance is a critical failure mode in rotating machinery,potentially causing severe equipment damage if undetected.Traditional vibration-based diagnostic methods rely on direct sensor contact,leading to installation challenges and measurement artifacts that can compromise accuracy.This study presents a novel radar-based framework for non-contact motor imbalance detection using 24 GHz continuous-wave radar.A dataset of 1802 experimental trials was sourced,covering four imbalance levels(0,10,20,30 g)across varying motor speeds(500–1500 rpm)and load torques(0–3 Nm).Dual-channel in-phase and quadrature radar signals were captured at 10,000 samples per second for 30-s intervals,preserving both amplitude and phase information for analysis.A multi-domain feature extraction methodology captured imbalance signatures in time,frequency,and complex signal domains.From 65 initial features,statistical analysis using Kruskal–Wallis tests identified significant descriptors,and recursive feature elimination with Random Forest reduced the feature set to 20 dimensions,achieving 69%dimensionality reduction without loss of performance.Six machine learning algorithms,Random Forest,Extra Trees Classifier,Extreme Gradient Boosting,Categorical Boosting,Support Vector Machine with radial basis function kernel,and k-Nearest Neighbors were evaluated with grid-search hyperparameter optimization and five-fold cross-validation.The Extra Trees Classifier achieved the best performance with 98.52%test accuracy,98%cross-validation accuracy,and minimal variance,maintaining per-class precision and recall above 97%.Its superior performance is attributed to its randomized split selection and full bootstrapping strategy,which reduce variance and overfitting while effectively capturing the nonlinear feature interactions and non-normal distributions present in the dataset.The model’s average inference time of 70 ms enables near real-time deployment.Comparative analysis demonstrates that the radar-based framework matches or exceeds traditional contact-based methods while eliminating their inherent limitations,providing a robust,scalable,and noninvasive solution for industrial motor condition monitoring,particularly in hazardous or space-constrained environments.
基金supported in part by the National Natural Science Foundation of China under Grant 62172368the Natural Science Foundation of Zhejiang Province under Grant LR22F020003.
文摘The development of brain-computer interfaces(BCI)based on motor imagery(MI)has greatly improved patients’quality of life with movement disorders.The classification of upper limb MI has been widely studied and applied in many fields,including rehabilitation.However,the physiological representations of left and right lower limb movements are too close and activated deep in the cerebral cortex,making it difficult to distinguish their features.Therefore,classifying lower limbs motor imagery is more challenging.In this study,we propose a feature extraction method based on functional connectivity,which utilizes phase-locked values to construct a functional connectivity matrix as the features of the left and right legs,which can effectively avoid the problem of physiological representations of the left and right lower limbs being too close to each other during movement.In addition,considering the topology and the temporal characteristics of the electroencephalogram(EEG),we designed a temporal-spatial convolutional network(TSGCN)to capture the spatiotemporal information for classification.Experimental results show that the accuracy of the proposed method is higher than that of existing methods,achieving an average classification accuracy of 73.58%on the internal dataset.Finally,this study explains the network mechanism of left and right foot MI from the perspective of graph theoretic features and demonstrates the feasibility of decoding lower limb MI.
基金supported by a grant from Ministry of Science and Technology China,No.2022ZD0204704(to WW)the National Natural Science Foundation of China,No.82301572(to XZ)the China Postdoctoral Science Foundation,No.2023M731202(to XZ)。
文摘Nonhuman primates are increasingly being used as animal models in neuroscience research.However,efficient neuronal tracing techniques for labeling motor neurons and primary sensory afferents in the monkey spinal cord are lacking.Here,by injecting the cholera toxin B subunit into the sciatic nerve of a rhesus monkey,we successfully labeled the motor neurons and primary sensory afferents in the lumbar and sacralspinal cord.Labeled alpha motor neurons were located in lamina IX of the L6–S1 segments,which innervate both flexors and extensors.The labeled primary sensory afferents were mainly myelinated Aβfibers that terminated mostly in laminae I and II of the L4–L7 segments.Together with the labeled proprioceptive afferents,the primary sensory afferents formed excitatory synapses with multiple types of spinal neurons.In summary,our methods successfully traced neuronal connections in the monkey spinal cord and can be used in spinal cord studies when nonhuman primates are used.
基金supported by Craig H.Neilsen Foundation,Wings for Life Foundation,Canadian Institutes of Health Research,and Fonds de Recherche Québec-Santé(to FB).
文摘Spinal cord injury(SCI)interrupts the flow of information between the brain and the spinal cord,thus leading to a loss of sensory information and motor paralysis of the body below the lesion.Surprisingly,most SCIs are incomplete and spare supraspinal pathways,especially those located within the peripheral white matter of the spinal cord,which includes reticulospinal pathways originating from the medullary reticular formation.Whereas there is abundant literature about the motor cortex,its corticospinal pathway,and its capacity to modulate functional recovery after SCI,less is known about the medullary reticular formation and its reticulospinal pathway.
基金supported and funded by the Deanship of Scientific Research at Imam Mohammad Ibn Saud Islamic University(IMSIU)(grant number IMSIU-DDRSP2601).
文摘Automated detection of Motor Imagery(MI)tasks is extremely useful for prosthetic arms and legs of stroke patients for their rehabilitation.Prediction of MI tasks can be performed with the help of Electroencephalogram(EEG)signals recorded by placing electrodes on the scalp of subjects;however,accurate prediction of MI tasks remains a challenge due to noise that is incurred during the EEG signal recording process,the extraction of a feature vector with high interclass variance,and accurate classification.The proposed method consists of preprocessing,feature extraction,and classification.First,EEG signals are denoised using a bandpass filter followed by Independent Component Analysis(ICA).Multiple channels are combined to form a single surrogate channel.Short Time Fourier Transform(STFT)is then applied to convert time domain EEG signals into the frequency domain.Handcrafted and automated features are extracted from EEG signals and then concatenated to form a single feature vector.We propose a customized two-dimensional Convolutional Neural Network(CNN)for automated feature extraction with high interclass variance.Feature selection is performed using Particle Swarm Optimization(PSO)to obtain optimal features.The final feature vector is passed to three different classifiers:Support Vector Machine(SVM),Random Forest(RF),and Long Short-Term Memory(LSTM).The final decision is made using the Model-Agnostic Meta Learning(MAML).The Proposed method has been tested on two datasets,including PhysioNet and BCI Competition IV-2a,and it achieved better results in terms of accuracy and F1 score than existing state-of-the-art methods.The proposed framework achieved an accuracy and F1 score of 96%on the PhysioNet dataset and 95.5%on the BCI Competition IV,dataset 2a.We also present SHapley Additive exPlanations(SHAP)and Gradient-weighted Class Activation Mapping(Grad-CAM)explainable techniques to enhance model interpretability in a clinical setting.
基金supported in part by the National Natural Science Foundation of China under Grants 52307049 and U23A20644in part by the Fundamental Research Funds for the Central Universities under Grant JZ2023HGTB0243+1 种基金in part by the Key Laboratory of Electric Drive and Control of Anhui Province under Grant DQKJ202403in part by the China Postdoctoral Science Foundation under Grant 2024M751073。
文摘The arc-linear motor(ALM) is a new type of special motor derived from the linear motor, which has the merits of high torque, compact structure and fast dynamic response. This kind of motor does not need a complex intermediate transmission device, it is used in some direct-drive applications for continuous rotation or limited angle motion. However, there is no systematic summary and generalization of the ALMs so far.Therefore, this paper systematically overviews the recent advances in ALMs for direct-drive systems. First, the evolution process and basic structure of the ALM are introduced. And then, various ALMs are reviewed with particular reference to motor topologies, working principle, motor performance,optimization design and control techniques. To heel, a comprehensive comparison of several typical ALMs is carried out. Finally, the application areas, main challenges and development trends of the ALMs are highlighted.
基金supported by the National Key R&D Program of China(2020YFE0205900 and 2022YEF0203200)the STI 2030-Major Project(2021ZD0200104 and 2022ZD0205203)+2 种基金the Shenzhen Science and Technology Program(RCYX20210706092100003,RCBS20221008093311027,and JCYJ20210324102006018)the Youth Innovation Promotion Association CAS(2022367)the Shenzhen Technological Research Center for Primate Translational Medicine grant(XMHT20220104005).
文摘Dear Editor,The primary motor cortex,also known as MOp in rodents,F1,or M1 in primates[1],plays a crucial role in autonomous motor control.It is interconnected with other motor control structures such as the basal ganglia,thalamus,and brainstem.Among these connections,the corticostriatal system plays a significant role in functions including action selection,motor control,sequence learning,and habit formation[2].
基金supported in part by the Universitat Politècnica de València under grant PAID-10-21supported through AMRITA Seed Grant(Proposal ID:ASG2022188)。
文摘Switched Reluctance Motors(SRMs),outfitted with rugged construction,good speed range,high torque density,and rare earth-free nature that outweigh induction motors(IM)and permanent magnet synchronous motor(PMSM),afford a broad range of applications in the domain of electric vehicles(EVs).Standard copper magnetic wire and low-carbon steel laminations are used to construct SRMs,which give them high efficiency in the range of 85-95%.Despite SRM's desirable features over traditional motor-speed drives,high torque ripples and radial distortions constrain their deployment in EVs.Precise rotor position is imperative for effective management of the speed and torque of SRMs.This paper provides an illustrative compendium on review of the torque-speed control and ripple mitigation techniques using design enhancements and control methods for SRM drives for EV applications.The various schemes were evaluated on their performance metricsoperational speed range,control complexity,practical realization,need for pre-stored parameters(look-up tables of current,inductance and torque profiles)and motor controller memory requirements.The findings provide valuable insights into balancing the gains and trade-offs associated with EV applications.Furthermore,they pinpoint opportunities for enhancement by analyzing the cost and technical aspects of different SRM controllers.
基金the Istanbul Technical University Scientific Research Projects Unit with grant number MGA-2022-43948。
文摘The hyperloop idea,which is one of the most ecofriendly,low-carbon emissions,and fossil fuel-efficient modes of transportation,has recently become quite popular.In this study,a double-sided linear induction motor(LIM)with 500 W of output power,60 N of thrust force and 200 V/38.58 Hz of supply voltage was designed to be used in hyperloop development competition hosted by the scientific and technological research council of turkey(TüB?TAK)rail transportation technologies institute(RUTE).In contrast to the studies in the literature,concentrated winding is preferred instead of distributed winding due to mechanical constraints.The electromagnetic design of LIM,whose mechanical and electrical requirements were determined considering the hyperloop development competition,was carried out by following certain steps.Then,the designed model was simulated and analyzed by finite element method(FEM),and the necessary optimizations have been performed to improve the motor characteristics.By examining the final model,the applicability of the concentrated winding type LIM for hyperloop technology has been investigated.Besides,the effects of primary material,railway material,and mechanical air-gap length on LIM performance were also investigated.In the practical phase of the study,the designed LIM has been prototyped and tested.The validation of the experimental results was achieved through good agreement with the finite element analysis results.
文摘Light-driven artificial molecular machines[1,2]are a class of functional small molecules powered by photochemical reactions,broadly divided into molecular motors and molecular photoswitches.Molecular motors[3,4],owing to their intrinsic point chirality and dynamic axial chirality,undergo unidirectional rotation about a carbon–carbon double bond when irradiated with light.In nature,biological molecular motors and pumps are ubiquitous:driving vision,intracellular transport,energy conversion,signal transduction,muscle contraction,and locomotion.
文摘Background:Acupuncture is widely used in modulating brain excitability and motor function,as a form of complementary and alternative medicine.However,there is no existing meta-analysis evaluating the effectiveness and safety of acupuncture on corticospinal excitability(CSE),and the credibility of the evidence has yet to be quantified.Objective:This study was designed to assess the efficacy and safety of electroacupuncture(EA)and manual acupuncture(MA)in enhancing brain excitability,specifically focusing on CSE as measured by transcranial magnetic stimulation(TMS).Search strategy:This study followed a systematic approach,searching 9 databases up to August 2024 and examining grey literature,in compliance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Inclusion criteria:Studies were included if they compared the clinical efficacy of EA or MA with sham acupuncture,no treatment or usual training.Data extraction and analysis:Three investigators independently conducted literature screening,data extraction,and risk of bias assessment.The primary outcome focused on motor-evoked potentials as measured by TMS,with treatment effects quantified using mean differences or standardized mean differences between pre-and post-treatment.Subgroup analyses were conducted using mixed-effects models,while random-effects or fixed-effects models were used to estimate average treatment differences across studies.Results:Based on 34 studies involving 1031 adults,acupuncture techniques significantly enhanced CSE.EA had a greater impact than MA,with effect sizes of 0.53 mV vs 0.43 mV(95%confidence interval[CI]:[0.30,0.76],P<0.00001 vs 95%CI:[0.28,0.59],P<0.00001).The 5 most frequently used acupoints were LI4(Hegu,32 times),ST36(Zusanli,10 times),LI11(Quchi,7 times),TE5(Waiguan,6 times),and GB34(Yanglingquan,5 times).Conclusion:This systematic review indicates that both EA and MA could effectively and safely enhance CSE,bringing the corticospinal pathway closer to the threshold for firing,which may ultimately improve motor function.LI4,ST36,LI11,TE5 and GB34 are the most commonly used acupoints.
基金supported by the Key Project at the Central Government Level:the ability establishment of sustainable use for valuable Chinese medicine resources(No.2060302)the National Natural Science Foundation of China(No.82104389)+2 种基金the Scientific and Technological Innovation Project of China Academy of Chinese Medical Sciences(No.CI2023E002)the High-level Key Discipline Program of National Administration of Traditional Chinese Medicine(No.ZYYZDXK-2023244)China Agricultural Research System of MOF and MARA(No.CARS-21).
文摘Pyrrolizidine alkaloids(PAs)are natural toxins generated as secondarymetabolites in plants,predominantly consisting of unsaturated PAs with diverse toxicities,such as hepatotoxicity.Echimidine,a prominent PA,is believed to exert various toxicological effects,including survival inhibition and induction of apoptosis of hepatocytes.However,the effects of echimidine on development remain unclear.We selected three concentrations of 0.02,0.2,and 2 mg/L to investigate the developmental toxicity of echimidine on zebrafish embryos.After a 7-day exposure,we observed hyperactivity and anxiety-like behavior in zebrafish larvae.Furthermore,we found that echimidine exposure significantly promoted embryonic motor neurodevelopment in geneticallymodified zebrafish.Next,we detected that echimidine exposure significantly increased the content of the excitatory neurotransmitter acetylcholine(ACh),accompanied by a significant decrease in acetylcholinesterase(AChE)activity.Conversely,echimidine led to a significant reduction in the content of the sedative neurotransmitterγ-aminobutyric acid(GABA),accompanied by abnormal gene expression of enzymes related to GABA synthesis.Moreover,we elucidated the strong direct binding of echimidine to zebrafish and human AChE protein through molecular docking.In summary,our study found that echimidine induced ACh accumulation possibly by inhibiting AChE activity,leading to motor neurodevelopmental abnormalities and hyperactivity in zebrafish larvae.This work provides important scientific knowledge on the effects and mechanisms of PAs on neural development,which is helpful for controlling the risk of PAs in food and protecting public health.
基金supported by STI 2030-Major Projects(2022ZD0208903)the National Natural Science Foundation of China(62336007)+3 种基金the Natural Science Foundation of Shandong Province(ZR2024QH582)the Pioneer R&D Program of Zhejiang Province(2024C03001)the Starry Night Science Fund of Zhejiang University Shanghai Institute for Advanced Study(SN-ZJU-SIAS-002)the Fundamental Research Funds for the Central Universities(2024ZFJH01-01).
文摘Reach-to-grasp movements require integrating information on both object location and grip type,but how these elements are planned and to what extent they interact remains unclear.We designed a new experimental paradigm in which monkeys sequentially received reach and grasp cues with delays,requiring them to retain and integrate both cues to grasp the goal object with appropriate hand gestures.Neural activity in the dorsal premotor cortex(PMd)revealed that reach and grasp were similarly represented yet not independent.Upon receiving the second cue,the PMd continued encoding the first,but over half of the neurons displayed incongruent modulations:enhanced,attenuated,or even reversed.Population-level analysis showed significant changes in encoding structure,forming distinct neural patterns.Leveraging canonical correlation analysis,we identified a shared subspace preserving the initial cue’s encoding,contributed by both congruent and incongruent neurons.Together,these findings reveal a novel perspective on the interactive planning of reach and grasp within the PMd,providing insights into potential applications for brain–machine interfaces.
