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1.
J Phys Chem Lett ; 14(50): 11324-11332, 2023 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-38064362

RESUMO

Owing to their conformational flexibility, soft molecules with side chains play a crucial role in molecular self-assembly or self-organization processes toward bottom-up building of supramolecular nanostructures. However, the influence of the rotating side chains in the confined space and subsequent surface-confined supramolecular self-assembly remains rarely explored. Herein, using the spatial confinement effect between soft building blocks, we realized size control on surface-confined supramolecular coordination self-assembly through the synergy between the repulsive steric hindrance and the attractive chemical interactions. Combining scanning tunneling microscopy with density functional theory calculations and Monte Carlo simulations, we elucidated the effective repulsive force generated by the thermal wiggling motions of the soft building blocks, allowing length tuning of the self-assembled chain structures. Through a delicate balance between the repulsive interaction induced by the spatial confinement effect and the coordinate chemical interaction, we provide a new strategy for controlling the geometry of the on-surface supramolecular nanostructures.

2.
Molecules ; 28(13)2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37446778

RESUMO

Herein, we demonstrate the supramolecular assemblies from a bifunctional ligand on Au(111), towards engineering two-dimensional (metal-) organic multilevel nanostructures. The bifunctional ligand employed, including two Br atoms and one carboxylic terminal, offers multiple bonding motifs with different configurations and binding energies. These bonding motifs are highly self-selective and self-recognizable, and thus afford the formation of subunits that contribute to engineering multilevel self-assemblies. Our scanning tunneling microscopy experiments, in combination with the density functional theory calculations, revealed various hydrogen, halogen and alkali-carboxylate bonding motifs dictating the different levels of the assemblies. The multilevel assembly protocol based on a judicious choice of multiple bonding motifs guarantees a deliberate control of surface-confined (metal-) organic nanostructures. Our findings may present new opportunities for the fabrication of complex two-dimensional (metal-) organic nanostructures with potential in applications of functionally diverse nanomaterials.


Assuntos
Metais , Nanoestruturas , Ligantes , Propriedades de Superfície , Metais/química , Nanoestruturas/química , Engenharia
3.
Bioengineering (Basel) ; 10(5)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37237648

RESUMO

Neural electrodes are core devices for research in neuroscience, neurological diseases, and neural-machine interfacing. They build a bridge between the cerebral nervous system and electronic devices. Most of the neural electrodes in use are based on rigid materials that differ significantly from biological neural tissue in flexibility and tensile properties. In this study, a liquid-metal (LM) -based 20-channel neural electrode array with a platinum metal (Pt) encapsulation material was developed by microfabrication technology. The in vitro experiments demonstrated that the electrode has stable electrical properties and excellent mechanical properties such as flexibility and bending, which allows the electrode to form conformal contact with the skull. The in vivo experiments also recorded electroencephalographic signals using the LM-based electrode from a rat under low-flow or deep anesthesia, including the auditory-evoked potentials triggered by sound stimulation. The auditory-activated cortical area was analyzed using source localization technique. These results indicate that this 20-channel LM-based neural electrode array satisfies the demands of brain signal acquisition and provides high-quality-electroencephalogram (EEG) signals that support source localization analysis.

4.
Cyborg Bionic Syst ; 4: 0017, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37027341

RESUMO

The cerebral cortex plays an important role in human and other animal adaptation to unpredictable terrain changes, but little was known about the functional network among the cortical areas during this process. To address the question, we trained 6 rats with blocked vision to walk bipedally on a treadmill with a random uneven area. Whole-brain electroencephalography signals were recorded by 32-channel implanted electrodes. Afterward, we scan the signals from all rats using time windows and quantify the functional connectivity within each window using the phase-lag index. Finally, machine learning algorithms were used to verify the possibility of dynamic network analysis in detecting the locomotion state of rats. We found that the functional connectivity level was higher in the preparation phase compared to the walking phase. In addition, the cortex pays more attention to the control of hind limbs with higher requirements for muscle activity. The level of functional connectivity was lower where the terrain ahead can be predicted. Functional connectivity bursts after the rat accidentally made contact with uneven terrain, while in subsequent movement, it was significantly lower than normal walking. In addition, the classification results show that using the phase-lag index of multiple gait phases as a feature can effectively detect the locomotion states of rat during walking. These results highlight the role of the cortex in the adaptation of animals to unexpected terrain and may help advance motor control studies and the design of neuroprostheses.

5.
Front Bioeng Biotechnol ; 11: 1169411, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37082218

RESUMO

Wearable flexible sensors are widely used in several applications such as physiological monitoring, electronic skin, and telemedicine. Typically, flexible sensors that are made of elastomeric thin-films lack sufficient permeability, which leads to skin inflammation, and more importantly, affects signal detection and consequently, reduces the sensitivity of the sensor. In this study, we designed a flexible nanofibrous membrane with a high air permeability (6.10 mm/s), which could be effectively used to monitor human motion signals and physiological signals. More specifically, a flexible membrane with a point (liquid metal nanoparticles)-line (carbon nanotubes)-plane (liquid metal thin-film) multiscale conductive structure was fabricated by combining liquid metal (LM) and carbon nanotubes (CNTs) with a polyurethane (PU) nanofibrous membrane. Interestingly, the excellent conductivity and fluidity of the liquid metal enhanced the sensitivity and stability of the membrane. More precisely, the gauge factor (GF) values of the membrane is 3.0 at 50% strain and 14.0 at 400% strain, which corresponds to a high strain sensitivity within the whole range of deformation. Additionally, the proposed membrane has good mechanical properties with an elongation at a break of 490% and a tensile strength of 12 MPa. Furthermore, the flexible membrane exhibits good biocompatibility and can efficiently monitor human health signals, thereby indicating potential for application in the field of wearable electronic devices.

6.
Adv Sci (Weinh) ; : e2204463, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36414403

RESUMO

Major depressive disorder (MDD) is a leading cause of disability worldwide. A comprehensive understanding of the molecular mechanisms of this disorder is critical for the therapy of MDD. In this study, it is observed that deubiquitinase Mysm1 is induced in the brain tissues from patients with major depression and from mice with depressive behaviors. The genetic silencing of astrocytic Mysm1 induced an antidepressant-like effect and alleviated the osteoporosis of depressive mice. Furthermore, it is found that Mysm1 knockdown led to increased ATP production and the activation of p53 and AMP-activated protein kinase (AMPK). Pifithrin α (PFT α) and Compound C, antagonists of p53 and AMPK, respectively, repressed ATP production and reversed the antidepressant effect of Mysm1 knockdown. Moreover, the pharmacological inhibition of astrocytic Mysm1 by aspirin relieved depressive-like behaviors in mice. The study reveals, for the first time, the important function of Mysm1 in the brain, highlighting astrocytic Mysm1 as a potential risk factor for depression and as a valuable target for drug discovery to treat depression.

7.
Biosens Bioelectron ; 216: 114600, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35961121

RESUMO

Nerve cuff electrodes have been used for decades as peripheral nerve interfacing devices in the fields of neural science, neural disease, and brain-machine interfacing. The currently-used cuff electrode is commonly based on rigid materials whose flexibility and tensile properties are far different from those of biological nervous tissue. Herein, a fluidic cuff electrode using a gallium-based liquid metal (LM) conductor is developed as a prototype artificial peripheral nerve. The results indicate that the LM cuff electrode has high flexibility and maintains outstanding conductivity. After implanted and connected to the sciatic nerve, the LM electrodes within the freely moving rats' bodies survive repeated body stretching and retain their long-term effectiveness in transmitting sciatic nerve signals with a high signal-to-noise ratio during two-week experiments. The LM electrodes are also proven capable of transmitting neural stimuli to the peripheral nerve on a long-term basis by triggering clear event-related potentials (ERPs) in terms of both the cortical potential and sciatic signal. These tests demonstrate that the LM electrodes meet the requirements of peripheral nerve signal recording and stimulation for long-term implantation, and have the potential to become a new generation of artificial peripheral nerve devices to interface with, supplement, or even enhance and replace the real peripheral nerve.


Assuntos
Técnicas Biossensoriais , Gálio , Tecido Nervoso , Animais , Estimulação Elétrica , Eletrodos , Eletrodos Implantados , Nervos Periféricos/fisiologia , Ratos
8.
J Neural Eng ; 19(2)2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-35263714

RESUMO

Background.Transcutaneous electrical nerve stimulation (TENS) is generally applied for tactile feedback in the field of prosthetics. The distinct mechanisms of evoked tactile perception between stimulus patterns in conventional TENS (cTENS) and neuromorphic TENS (nTENS) are relatively unknown. This is the first study to investigate the neurobiological effect of nTENS for cortical functional mechanism in evoked tactile perception.Methods.Twenty-one healthy participants were recruited in this study. Electroencephalogram (EEG) was recorded while the participants underwent a tactile discrimination task. One cTENS pattern (square pattern) and two nTENS patterns (electromyography and single motor unit patterns) were applied to evoke tactile perception in four fingers, including the right and left index and little fingers. EEG was preprocessed and somatosensory-evoked potentials (SEPs) were determined. Then, source-level functional networks based on graph theory were evaluated, including clustering coefficient, path length, global efficiency, and local efficiency in six frequency bands.Main results.Behavioral results suggested that the single motor units (SMUs) pattern of nTENS was the most natural tactile perception. SEPs results revealed that SMU pattern exhibited significant shorter latency in P1 and N1 components than the other patterns, while nTENS patterns have significantly longer latency in P3 component than cTENS pattern. Cortical functional networks showed that the SMU pattern had the lowest short path and highest efficiency in beta and gamma bands.Conclusion.This study highlighted that distinct TENS patterns could affect brain activities. The new characteristics in tactile manifestation of nTENS would provide insights for the application of tactile perception restoration.


Assuntos
Percepção do Tato , Estimulação Elétrica Nervosa Transcutânea , Eletroencefalografia , Potenciais Somatossensoriais Evocados/fisiologia , Humanos , Córtex Somatossensorial/fisiologia , Tato , Percepção do Tato/fisiologia
9.
Biosensors (Basel) ; 11(12)2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34940260

RESUMO

Neural interfaces typically focus on one or two sites in the motoneuron system simultaneously due to the limitation of the recording technique, which restricts the scope of observation and discovery of this system. Herein, we built a system with various electrodes capable of recording a large spectrum of electrophysiological signals from the cortex, spinal cord, peripheral nerves, and muscles of freely moving animals. The system integrates adjustable microarrays, floating microarrays, and microwires to a commercial connector and cuff electrode on a wireless transmitter. To illustrate the versatility of the system, we investigated its performance for the behavior of rodents during tethered treadmill walking, untethered wheel running, and open field exploration. The results indicate that the system is stable and applicable for multiple behavior conditions and can provide data to support previously inaccessible research of neural injury, rehabilitation, brain-inspired computing, and fundamental neuroscience.


Assuntos
Atividade Motora , Caminhada , Animais , Encéfalo/fisiologia , Vias Eferentes , Eletrodos Implantados , Ratos
10.
Micromachines (Basel) ; 12(8)2021 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-34442623

RESUMO

Epilepsy is common brain dysfunction, where abnormal synchronized activities can be observed across multiple brain regions. Low-frequency focused pulsed ultrasound has been proven to modulate the epileptic brain network. In this study, we used two modes of low-intensity focused ultrasound (pulsed-wave and continuous-wave) to sonicate the brains of KA-induced epileptic rats, analyzed the EEG functional brain connections to explore their respective effect on the epileptic brain network, and discuss the mechanism of ultrasound neuromodulation. By comparing the brain network characteristics before and after sonication, we found that two modes of ultrasound both significantly affected the functional brain network, especially in the low-frequency band below 12 Hz. After two modes of sonication, the power spectral density of the EEG signals and the connection strength of the brain network were significantly reduced, but there was no significant difference between the two modes. Our results indicated that the ultrasound neuromodulation could effectively regulate the epileptic brain connections. The ultrasound-mediated attenuation of epilepsy was independent of modes of ultrasound.

11.
Brain Sci ; 11(6)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34071964

RESUMO

(1) Background: Ultrasound has been used for noninvasive stimulation and is a promising technique for treating neurological diseases. Epilepsy is a common neurological disorder, that is attributed to uncontrollable abnormal neuronal hyperexcitability. Abnormal synchronized activities can be observed across multiple brain regions during a seizure. (2) Methods: we used low-intensity focused ultrasound (LIFU) to sonicate the brains of epileptic rats, analyzed the EEG functional brain network to explore the effect of LIFU on the epileptic brain network, and continued to explore the mechanism of ultrasound neuromodulation. LIFU was used in the hippocampus of epileptic rats in which a seizure was induced by kainic acid. (3) Results: By comparing the brain network characteristics before and after sonication, we found that LIFU significantly impacted the functional brain network, especially in the low-frequency band. The brain network connection strength across multiple brain regions significantly decreased after sonication compared to the connection strength in the control group. The brain network indicators (the path length, clustering coefficient, small-worldness, local efficiency and global efficiency) all changed significantly in the low-frequency. (4) Conclusions: These results revealed that LIFU could reduce the network connections of epilepsy circuits and change the structure of the brain network at the whole-brain level.

12.
Brain Sci ; 11(3)2021 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-33803159

RESUMO

Previous findings have suggested that the cortex involved in walking control in freely locomotion rats. Moreover, the spectral characteristics of cortical activity showed significant differences in different walking conditions. However, whether brain connectivity presents a significant difference during rats walking under different behavior conditions has yet to be verified. Similarly, whether brain connectivity can be used in locomotion detection remains unknown. To address those concerns, we recorded locomotion and implanted electroencephalography signals in freely moving rats performing two kinds of task conditions (upslope and downslope walking). The Granger causality method was used to determine brain functional directed connectivity in rats during these processes. Machine learning algorithms were then used to categorize the two walking states, based on functional directed connectivity. We found significant differences in brain functional directed connectivity varied between upslope and downslope walking. Moreover, locomotion detection based on brain connectivity achieved the highest accuracy (91.45%), sensitivity (90.93%), specificity (91.3%), and F1-score (91.43%). Specifically, the classification results indicated that connectivity features in the high gamma band contained the most discriminative information with respect to locomotion detection in rats, with the support vector machine classifier exhibiting the most efficient performance. Our study not only suggests that brain functional directed connectivity in rats showed significant differences in various behavioral contexts but also proposed a method for classifying the locomotion states of rat walking, based on brain functional directed connectivity. These findings elucidate the characteristics of neural information interaction between various cortical areas in freely walking rats.

13.
Exp Physiol ; 106(7): 1612-1620, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33866642

RESUMO

NEW FINDINGS: What is the central question of this study? White matter lesions (WMLs) are a brain disease characterized by altered brain structural and functional connectivity, but findings have shown an inconsistent pattern: are there distinct cortical thickness changes in patients with WMLs subtypes? What is the main finding and its importance? Patients with WMLs with non-dementia vascular cognitive impairment and WMLs with vascular dementia showed distinct pathophysiology in cortical thickness. These neural correlates of WMLs should be considered in future treatment. ABSTRACT: The effect of cortical thickness on white matter lesions (WMLs) in patients with distinct vascular cognitive impairments is relatively unknown. This study investigated the correlation between cortical thickness and vascular cognitive manifestations. WML patients and healthy controls from Beijing Tiantan Hospital between 2014 and 2018 were included. The patients were further divided into two subgroups, namely WMLs with non-dementia vascular cognitive impairment (WML-VCIND) and WMLs with vascular dementia (WML-VaD) according to the Clinical Dementia Rating (CDR) scale and the Beijing version of the Montreal Cognitive Assessment (MoCA). Changes in cortical thickness were calculated using FreeSurfer. Pearson's correlation analysis was performed to explore the relationship between cognitive manifestations and cortical thickness in WML patients. Forty-five WML patients and 23 healthy controls were recruited. The WML group exhibited significant difference in cortical thickness compared to the control group. Significantly decreased cortical thickness in the middle and superior frontal gyri, middle temporal gyrus, angular gyrus and insula was found in the WML-VaD versus WML-VCIND subgroup. Cortical thickness deficits of the left caudal middle frontal gyrus (r = 0.451, P = 0.002), left rostral middle frontal gyrus (r = 0.514, P < 0.001), left superior frontal gyrus (r = 0.410, P = 0.006), right middle temporal gyrus (r = 0.440, P = 0.003), right pars triangularis (r = 0.462, P = 0.002), right superior frontal gyrus (r = 0.434, P = 0.004) and right insula (r = 0.499, P = 0.001) were positively correlated with the MoCA score in WML patients. The specific pattern of cortical thickness deficits in the WML-VaD subgroup revealed the pathophysiology of WMLs, which should be considered in future treatment of WMLs.


Assuntos
Disfunção Cognitiva , Demência , Substância Branca , Encéfalo , Disfunção Cognitiva/patologia , Demência/patologia , Humanos , Imageamento por Ressonância Magnética , Substância Branca/patologia
14.
Sensors (Basel) ; 21(8)2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33916907

RESUMO

The loss of mobility function and sensory information from the arm, hand, and fingertips hampers the activities of daily living (ADL) of patients. A modern bionic prosthetic hand can compensate for the lost functions and realize multiple degree of freedom (DoF) movements. However, the commercially available prosthetic hands usually have limited DoFs due to limited sensors and lack of stable classification algorithms. This study aimed to propose a controller for finger joint angle estimation by surface electromyography (sEMG). The sEMG data used for training were gathered with the Myo armband, which is a commercial EMG sensor. Two features in the time domain were extracted and fed into a nonlinear autoregressive model with exogenous inputs (NARX). The NARX model was trained with pre-selected parameters using the Levenberg-Marquardt algorithm. Comparing with the targets, the regression correlation coefficient (R) of the model outputs was more than 0.982 over all test subjects, and the mean square error was less than 10.02 for a signal range in arbitrary units equal to [0, 255]. The study also demonstrated that the proposed model could be used in daily life movements with good accuracy and generalization abilities.


Assuntos
Articulações dos Dedos , Dispositivos Eletrônicos Vestíveis , Atividades Cotidianas , Algoritmos , Eletromiografia , Mãos , Humanos
15.
Biology (Basel) ; 11(1)2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-35053035

RESUMO

Humans and other animals can quickly respond to unexpected terrains during walking, but little is known about the cortical dynamics in this process. To study the impact of unexpected terrains on brain activity, we allowed rats with blocked vision to walk on a treadmill in a bipedal posture and then walk on an uneven area at a random position on the treadmill belt. Whole brain EEG signals and hind limb kinematics of bipedal-walking rats were recorded. After encountering unexpected terrain, the θ band power of the bilateral M1, the γ band power of the left S1, and the θ to γ band power of the RSP significantly decreased compared with normal walking. Furthermore, when the rats left uneven terrain, the ß band power of the bilateral M1 and the α band power of the right M1 decreased, while the γ band power of the left M1 significantly increased compared with normal walking. Compared with the flat terrain, the θ to low ß (3-20 Hz) band power of the bilateral S1 increased after the rats contacted the uneven terrain and then decreased in the single- or double- support phase. These results support the hypothesis that unexpected terrains induced changes in cortical activity.

16.
Brain Res ; 1751: 147188, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33137325

RESUMO

Longstanding theories in the field of neurophysiology have held that walking in rats is an unconscious, rhythmic locomotion that does not require cortical involvement. However, recent studies have suggested that the extent of cortical involvement during walking actually varies depending on the environmental conditions. To determine the impact of environmental conditions on cortical engagement in freely walking rats, we recorded limb kinematics and signals from implanted electroencephalography arrays in rats performing a series of natural behaviors. We found that rat gaits were significantly different across various locomotion terrains (e.g. walking on an upslope vs. downslope). Further, rat forelimbs and hindlimbs showed similar patterns of motion. The results also suggested that rat cortical engagement during walking varied across environmental conditions. Specifically, α band power significantly increased during 30° downslope walking in the posterior parietal, left secondary motor, and left somatosensory clusters. Additionally, during 30° upslope walking, the ß band power was greater in the left primary motor and left and right secondary motor sources. Further, rats walking on up- or downslopes of varying steepness were found to have different cortical activities. Compared with 10° downslope walking, α band power was greater during 30° downslope locomotion in the left primary motor and somatosensory sources. These findings support the hypothesis that cortical contribution during walking in rats is influenced by environmental conditions, underlining the importance of goal-directed behaviors for motor function rehabilitation and neuro-prosthetic control in brain-machine interfaces.


Assuntos
Córtex Cerebral/metabolismo , Caminhada/fisiologia , Animais , Fenômenos Biomecânicos , Interfaces Cérebro-Computador , China , Eletroencefalografia/instrumentação , Eletroencefalografia/métodos , Marcha/fisiologia , Membro Posterior/fisiologia , Locomoção/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley
17.
Medicine (Baltimore) ; 99(26): e20852, 2020 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-32590783

RESUMO

RATIONALE: Either malacoplakia or xanthogranulomatous cystitis (XC) is a rare chronic infection disease of urinary bladder, which often mimics bladder masses undifferentiated from malignance and results in severe lower urinary tract symptoms. The malacoplakia combined with XC is even rarer in the literature. PATIENT CONCERNS: A 64-year-old female, who presented with nocturia, frequency of micturition, severe urgency with occasional urinary incontinence, and recurrent hematuria for >2 years, was diagnosed with azotemia and anemia. In addition, two 1.0 × 1.0 cm masses of bladder were detected by computer tomography. DIAGNOSES: Malacoplakia combined with xanthogranulomas cystitis was diagnosed histologically. Video urodynamic test showed poor bladder compliance (9 mL/comH2O), markedly decreased maximum bladder capacity (120 mL), and right vesicoureteral reflux at a low intravesical pressure level (25 cmH2O). INTERVENTIONS: Transurethral resection of bladder masses was carried out after treatment of urinary infection by intravenous piperacillin-tazobactam. Oral Ciprofloxacin and Tolterodine were postoperatively used to prevent recurrent lower urinary tract infections and alleviate detrusor overactivity. OUTCOMES: The treatment did not alleviate azotemia, frequency, urgency with incontinence, and bilateral hydroureteronephrosis, but the patient refused to undergo bladder augmentation on account of her poor economic status. LESSONS: Malacoplakia or/and xanthogranulomas cystitis may lead to poor bladder compliance and video urodynamic study should be considered in patients with refractory chronic lower urinary tract symptoms.


Assuntos
Cistite/complicações , Malacoplasia/complicações , Bexiga Urinária/anormalidades , Cistite/fisiopatologia , Feminino , Humanos , Malacoplasia/fisiopatologia , Pessoa de Meia-Idade , Noctúria/etiologia , Tomografia Computadorizada por Raios X/métodos , Bexiga Urinária/fisiopatologia , Incontinência Urinária/etiologia , Infecções Urinárias/etiologia , Infecções Urinárias/fisiopatologia
18.
Sensors (Basel) ; 20(1)2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31861254

RESUMO

A rodent real-time tracking framework is proposed to automatically detect and track multi-objects in real time and output the coordinates of each object, which combines deep learning (YOLO v3: You Only Look Once, v3), the Kalman Filter, improved Hungarian algorithm, and the nine-point position correction algorithm. A model of a Rat-YOLO is trained in our experiment. The Kalman Filter model is established in an acceleration model to predict the position of the rat in the next frame. The predicted data is used to fill the losing position of rats if the Rat-YOLO doesn't work in the current frame, and to associate the ID between the last frame and current frame. The Hungarian assigned algorithm is used to show the relationship between the objects of the last frame and the objects of the current frame and match the ID of the objects. The nine-point position correction algorithm is presented to adjust the correctness of the Rat-YOLO result and the predicted results. As the training of deep learning needs more datasets than our experiment, and it is time-consuming to process manual marking, automatic software for generating labeled datasets is proposed under a fixed scene and the labeled datasets are manually verified in term of their correctness. Besides this, in an off-line experiment, a mask is presented to remove the highlight. In this experiment, we select the 500 frames of the data as the training datasets and label these images with the automatic label generating software. A video (of 2892 frames) is tested by the trained Rat model and the accuracy of detecting all the three rats is around 72.545%, however, the Rat-YOLO combining the Kalman Filter and nine-point position correction arithmetic improved the accuracy to 95.194%.

19.
Exp Ther Med ; 18(5): 3357-3364, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31602209

RESUMO

Functional degradation of the motor cortex usually results from brain injury, stroke, limb amputation, aging or other diseases. Currently, there are no ideal means of treatment, other than medication and sports rehabilitation. The present study investigated whether electrical stimulation of the sciatic nerve can activate the motor-related area of the brain. The study is based on a self-developed fully implantable nerve electrical stimulator and a self-developed multi-channel electroencephalogram (EEG) electrode array. The sciatic nerves of Sprague-Dawley rats (sorted into old and young groups) were stimulated by the electrical stimulator under anesthesia, and the EEG signal was recorded simultaneously. The relationship between sciatic nerve stimulation and brain activity was analyzed. The results showed that when the sciatic nerve was stimulated by the implanted electrical stimulator, motor-related channels were activated, causing contraction of the left leg. It was found that at the frequency band of 8-16 Hz, the EEG signal in the right motor area was higher than at other frequency bands. This phenomenon was identical in both young and old rats. The results indicated that electrical stimulation of the sciatic nerve can activate the motor region of the rat brain, and provided evidence that stimulation of the sciatic nerve could be a method of preventing motor cortex degeneration.

20.
Exp Physiol ; 104(11): 1711-1716, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31475750

RESUMO

NEW FINDINGS: What is the central question of this study? Research has reported that some sensory input, such as auditory and olfactory input, can affect subliminal visual processing. However, it is important to address whether tactile input, another form of elementary sensory input, could influence the interocular rivalry process. What is the main finding and its importance? We present several pieces of evidence regarding the influences of familiar tactile shapes and temperature on continuous flash suppression. Our findings provide support for the hypothesis that there is a cross-modal effect on subconscious visual semantic processing of Chinese characters. More specifically, tactile sensations affect subliminal processing of visual information. ABSTRACT: Tactile and visual sensations are the most vital human functions for obtaining environmental information. However, whether tactile information influences visual processing remains unclear. In this study, a breaking continuous flash suppression (b-CFS) protocol was used to measure the extent to which tactile sensations facilitate visual processing subconsciously. In experiment 1, finger stimulation with cold and hot temperatures served as primers for the words 'cold' and 'hot', which were in turn suppressed by CFS. In experiment 2, subjects viewed the upright or inverted word 'cell phone', with or without tactile priming of holding a cell phone in their hand. Results demonstrated that the tactile primer significantly shortened the reaction time in the touch group compared with the control group in both experiments. Thus, the tactile sensation of a familiar article and/or temperature appears to facilitate corresponding visual semantic recognition to break CFS earlier.


Assuntos
Tempo de Reação/fisiologia , Tato/fisiologia , Adulto , Cognição/fisiologia , Temperatura Baixa , Feminino , Temperatura Alta , Humanos , Estudos Longitudinais , Masculino , Semântica , Adulto Jovem
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