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1.
Ergonomics ; 66(8): 1099-1117, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36214560

RESUMEN

ABSTRACUser decision-making concerning critical operations is very important to nuclear power plant (NPP) safety. The NPP interface is the main information source that guides decision-making; thus, a good interface design is essential. Among the interface design factors such as interface complexity, layout and colour, interface complexity (the amount of information in the interface) has the greatest impact on NPP operator decision-making. This paper used the event-related potential (ERP) to evaluate the impact of interface complexity on user decision-making and found interface complexity has a specific range suitable for decision-making. Based on this important finding, a fast and economical method of evaluating NPP interfaces in all design phases was proposed. This method compensates for the shortcomings of traditional methods, such as heuristic evaluation and experimental evaluation, which are inconvenient for evaluating interfaces in initial design phase; it can also be applied to interfaces with similar features in other industrial fields. Practitioner summary: Evaluation of the impact of NPP interface complexity on user decision-making through an ERP experiment revealed a specific range of interface complexity that facilitates user decision-making. Based on this finding, a new, fast and inexpensive interface evaluation method was proposed. Abbreviations: NPP: nuclear power plant, it is a thermal power station in which the heat source is a nuclear reactor; ERP: event-related potential, it is the measured brain response that is the direct result of a specific cognitive, or motor event.


Asunto(s)
Plantas de Energía Nuclear , Interfaz Usuario-Computador , Humanos , Potenciales Evocados
2.
Entropy (Basel) ; 25(12)2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38136516

RESUMEN

The digital interface is crucial for nuclear plant operators, influencing their decision-making significantly. However, evaluations of these interfaces often overlook users' decision-making performance; lack established standards, typically occurring after the design phase; and are unsuitable for large-scale assessments. Recognizing the vital role of interface information, this paper built on our previous research and proposed a method tailored for nuclear power plant interfaces, utilizing image entropy to evaluate the impact of information on decision-making. A comparative analysis with an experimental evaluation method empirically validated the effectiveness of the proposed method. This research offers a unique decision-making-centric method to interface evaluation, providing a standardized, adaptable framework for various design phases and enabling extensive and rapid evaluations.

3.
Sensors (Basel) ; 21(17)2021 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-34502853

RESUMEN

Transcranial focused ultrasound (tFUS) has great potential in brain imaging and therapy. However, the structural and acoustic differences of the skull will cause a large number of technical problems in the application of tFUS, such as low focus energy, focal shift, and defocusing. To have a comprehensive understanding of the skull effect on tFUS, this study investigated the effects of the structural parameters (thickness, radius of curvature, and distance from the transducer) and acoustic parameters (density, acoustic speed, and absorption coefficient) of the skull model on tFUS based on acrylic plates and two simulation methods (self-programming and COMSOL). For structural parameters, our research shows that as the three factors increase the unit distance, the attenuation caused from large to small is the thickness (0.357 dB/mm), the distance to transducer (0.048 dB/mm), and the radius of curvature (0.027 dB/mm). For acoustic parameters, the attenuation caused by density (0.024 dB/30 kg/m3) and acoustic speed (0.021 dB/30 m/s) are basically the same. Additionally, as the absorption coefficient increases, the focus acoustic pressure decays exponentially. The thickness of the structural parameters and the absorption coefficient of the acoustic parameters are the most important factors leading to the attenuation of tFUS. The experimental and simulation trends are highly consistent. This work contributes to the comprehensive and quantitative understanding of how the skull influences tFUS, which further enhances the application of tFUS in neuromodulation research and treatment.


Asunto(s)
Cráneo , Transductores , Acústica , Encéfalo , Simulación por Computador , Cráneo/diagnóstico por imagen
4.
Sensors (Basel) ; 20(15)2020 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-32731432

RESUMEN

The brain-computer interface (BCI) spellers based on steady-state visual evoked potentials (SSVEPs) have recently been widely investigated for their high information transfer rates (ITRs). This paper aims to improve the practicability of the SSVEP-BCIs for high-speed spelling. The system acquired the electroencephalogram (EEG) data from a self-developed dedicated EEG device and the stimulation was arranged as a keyboard. The task-related component analysis (TRCA) spatial filter was modified (mTRCA) for target classification and showed significantly higher performance compared with the original TRCA in the offline analysis. In the online system, the dynamic stopping (DS) strategy based on Bayesian posterior probability was utilized to realize alterable stimulating time. In addition, the temporal filtering process and the programs were optimized to facilitate the online DS operation. Notably, the online ITR reached 330.4 ± 45.4 bits/min on average, which is significantly higher than that of fixed stopping (FS) strategy, and the peak value of 420.2 bits/min is the highest online spelling ITR with a SSVEP-BCI up to now. The proposed system with portable EEG acquisition, friendly interaction, and alterable time of command output provides more flexibility for SSVEP-based BCIs and is promising for practical high-speed spelling.

5.
Phytother Res ; 32(6): 1056-1063, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29468740

RESUMEN

20(S)-protopanaxatriol (PPT), one of the ginsenosides from Panax ginseng, has been reported to have neuroprotective effects and to improve memory. The present study was designed to investigate the protective effect of PPT on scopolamine-induced cognitive deficits in mice. Male Institute of Cancer Research mice were pretreated with 2 different doses of PPT (20 and 40 µmol/kg) for 27 days by intraperitoneal injection, and scopolamine (0.75 mg/kg) was injected intraperitoneally for 9 days to induce memory impairment. Thirty minutes after the last pretreatment, the locomotor activity was firstly examined to evaluate the motor function of mice. Then, memory-related behaviors were evaluated, and the related mechanism was further researched. It was founded that PPT treatment significantly reversed scopolamine-induced cognitive impairment in the object location recognition experiment, the Morris water maze test, and the passive avoidance task, showing memory-improving effects. PPT also significantly improved cholinergic system reactivity and suppressed oxidative stress, indicated by inhibition of acetylcholinesterase activity, elevation of acetylcholine levels, increasing superoxide dismutase activity and lowering levels of malondialdehyde in the hippocampus. In addition, the expression levels of Egr-1, c-Jun, and cAMP responsive element binding in the hippocampus were significantly elevated by PPT administration. These results suggest that PPT may be a potential drug candidate for the treatment of cognitive deficit in Alzheimer's disease.


Asunto(s)
Disfunción Cognitiva/inducido químicamente , Fármacos Neuroprotectores/uso terapéutico , Sapogeninas/uso terapéutico , Escopolamina/efectos adversos , Animales , Disfunción Cognitiva/tratamiento farmacológico , Masculino , Ratones , Fármacos Neuroprotectores/farmacología , Estrés Oxidativo , Sapogeninas/farmacología
6.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 34(6): 857-862, 2017 Dec 01.
Artículo en Zh | MEDLINE | ID: mdl-29761979

RESUMEN

Astronauts who are exposed to weightless environment in long-term spaceflight might encounter bone density and mass loss for the mechanical stimulus is smaller than normal value. This study built a three dimensional model of human femur to simulate the remodeling process of human femur during bed rest experiment based on finite element analysis (FEA). The remodeling parameters of this finite element model was validated after comparing experimental and numerical results. Then, the remodeling process of human femur in weightless environment was simulated, and the remodeling function of time was derived. The loading magnitude and loading cycle on human femur during weightless environment were increased to simulate the exercise against bone loss. Simulation results showed that increasing loading magnitude is more effective in diminishing bone loss than increasing loading cycles, which demonstrated that exercise of certain intensity could help resist bone loss during long-term spaceflight. At the end, this study simulated the bone recovery process after spaceflight. It was found that the bone absorption rate is larger than bone formation rate. We advise that astronauts should take exercise during spaceflight to resist bone loss.

7.
BMC Complement Altern Med ; 15: 55, 2015 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-25888276

RESUMEN

BACKGROUND: Tong Luo Jiu Nao (TLJN), a modern formula of Chinese medicine extracts on the basis of Traditional Chinese Medicine theory, has been used to treat dementia. The present study aimed to investigate its ameliorating effects on Aß1-40-induced cognitive impairment in rats using a series of novel reward-directed instrumental learning (RDIL) tasks, and to determine its possible mechanism of action. METHODS: Rats were pretreated with TLJN extract (0.9 and 1.8 g/kg, p.o.) for 10 daysbefore surgery, and were trained to gain reward reinforcement by lever pressing at the meantime. Thereafter, rats received a bilateral microinjection of Aß1-40 in CA1 regions of the hippocampus. Cognitive performance was evaluated with the goal directed (higher response ratio) and habit (visual signal discrimination and extinction) learning tasks, as well as on the levels of biochemical parameters and molecules. RESULTS: Our findings first demonstrated that TLJN can improve Aß1-40-induced amnesia in RDIL via enhancing the comprehension of action-outcome association and the utilization of cue information to guide behavior. Then, its ameliorating effects should attribute to the modulation of ERK/CaMKII/CREB signaling in the hippocampus. CONCLUSION: TLJN can markedly enhance cognitions of Aß1-40 microinjection animal model in adaptive behavioral tasks. It has the potential, possibly as complementary and alternative therapy, to prevent and/or delay the deterioration of cognitive impairment in AD.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Trastornos del Conocimiento/tratamiento farmacológico , Cognición/efectos de los fármacos , Medicamentos Herbarios Chinos/uso terapéutico , Hipocampo/efectos de los fármacos , Aprendizaje/efectos de los fármacos , Fitoterapia , Adaptación Psicológica , Enfermedad de Alzheimer/metabolismo , Amnesia/tratamiento farmacológico , Amnesia/metabolismo , Péptidos beta-Amiloides/efectos adversos , Péptidos beta-Amiloides/metabolismo , Animales , Proteína Quinasa Tipo 2 Dependiente de Calcio Calmodulina/metabolismo , Trastornos del Conocimiento/metabolismo , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Demencia , Modelos Animales de Enfermedad , Medicamentos Herbarios Chinos/farmacología , Retroalimentación Psicológica/efectos de los fármacos , Hipocampo/metabolismo , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Masculino , Medicina Tradicional China , Fragmentos de Péptidos/efectos adversos , Fragmentos de Péptidos/metabolismo , Ratas Wistar , Transducción de Señal
8.
Sensors (Basel) ; 14(3): 4899-913, 2014 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-24618775

RESUMEN

Sliding tactile perception is a basic function for human beings to determine the mechanical properties of object surfaces and recognize materials. Imitating this process, this paper proposes a novel finger-shaped tactile sensor based on a thin piezoelectric polyvinylidene fluoride (PVDF) film for surface texture measurement. A parallelogram mechanism is designed to ensure that the sensor applies a constant contact force perpendicular to the object surface, and a 2-dimensional movable mechanical structure is utilized to generate the relative motion at a certain speed between the sensor and the object surface. By controlling the 2-dimensional motion of the finger-shaped sensor along the object surface, small height/depth variation of surface texture changes the output charge of PVDF film then surface texture can be measured. In this paper, the finger-shaped tactile sensor is used to evaluate and classify five different kinds of linen. Fast Fourier Transformation (FFT) is utilized to get original attribute data of surface in the frequency domain, and principal component analysis (PCA) is used to compress the attribute data and extract feature information. Finally, low dimensional features are classified by Support Vector Machine (SVM). The experimental results show that this finger-shaped tactile sensor is effective and high accurate for discriminating the five textures.


Asunto(s)
Biomimética , Dedos , Textiles , Tacto/fisiología , Ropa de Cama y Ropa Blanca , Diseño de Equipo , Dedos/fisiología , Humanos , Polivinilos , Análisis de Componente Principal , Máquina de Vectores de Soporte , Propiedades de Superficie
9.
J Eye Mov Res ; 17(1)2024.
Artículo en Inglés | MEDLINE | ID: mdl-38694263

RESUMEN

The motion of rotation, which served as a dynamic symbol within human-computer interfaces, has garnered extensive attention in interface and graphic design. This study aimed to establish speed benchmarks for interface design by exploring visual system preferences for the perception of both simple and complex rotating icons within the velocity range of 5-1800 degrees per second. The research conducted two experiments with 12 participants to examine the observers' just noticeable difference in speed (JNDS) and perceived speed for rotational icons. Experiment one measured the JNDS over eight-speed levels using a constant stimulus method, achieving a range of 14.9-29%. Building on this, experiment two proposed a sequence of speeds within the given range and used a rating scale method to assess observers ' subjective perception of the speed series' rapidity. The findings indicated that speed increases impacted the ability to differentiate between speeds; key points for categorizing low, medium, and high speeds were identified at 10, 180, and 720 degrees/s, respectively. Shape complexity was found to modulate the visual system's perception of actual speed, such that at rotation speeds above 180 degrees/s, complex icons appeared to rotate faster than simpler ones. Most importantly, the study applied quantitative methods and metrology to interface design, offering a more scientific approach to the design workflow.

10.
Circulation ; 126(25): 3028-40, 2012 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-23151343

RESUMEN

BACKGROUND: Sustained cardiac pressure overload-induced hypertrophy and pathological remodeling frequently leads to heart failure. Casein kinase-2 interacting protein-1 (CKIP-1) has been identified to be an important regulator of cell proliferation, differentiation, and apoptosis. However, the physiological role of CKIP-1 in the heart is unknown. METHODS AND RESULTS: The results of echocardiography and histology demonstrate that CKIP-1-deficient mice exhibit spontaneous cardiac hypertrophy with aging and hypersensitivity to pressure overload-induced pathological cardiac hypertrophy, as well. Transgenic mice with cardiac-specific overexpression of CKIP-1 showed resistance to cardiac hypertrophy in response to pressure overload. The results of GST pull-down and coimmunoprecipitation assays showed the interaction between CKIP-1 and histone deacetylase 4 (HDAC4), through which they synergistically inhibited transcriptional activity of myocyte-specific enhancer factor 2C. By directly interacting with the catalytic subunit of phosphatase 2A, CKIP-1 overexpression enhanced the binding of catalytic subunit of phosphatase-2A to HDAC4 and promoted HDAC4 dephosphorylation. CONCLUSIONS: CKIP-1 was found to be an inhibitor of cardiac hypertrophy by upregulating the dephosphorylation of HDAC4 through the recruitment of protein phosphatase 2A. These results demonstrated a unique function of CKIP-1, by which it suppresses cardiac hypertrophy through its capacity to regulate HDAC4 dephosphorylation and fetal cardiac genes expression.


Asunto(s)
Cardiomegalia/prevención & control , Proteínas Portadoras/fisiología , Histona Desacetilasas/fisiología , Proteína Fosfatasa 2/fisiología , Factores de Edad , Animales , Factores de Transcripción MEF2 , Masculino , Ratones , Ratones Noqueados , Miocardio/metabolismo , Factores Reguladores Miogénicos/fisiología , Fosforilación , Transcripción Genética
11.
Neural Plast ; 2013: 130642, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24349797

RESUMEN

People with neuropsychiatric disorders such as schizophrenia often display deficits in spatial working memory and attention. Evaluating working memory and attention in schizophrenia patients is usually based on traditional tasks and the interviewer's judgment. We developed a simple Spatial Working Memory and Attention Test on Paired Symbols (SWAPS). It takes only several minutes to complete, comprising 101 trials for each subject. In this study, we tested 72 schizophrenia patients and 188 healthy volunteers in China. In a healthy control group with ages ranging from 12 to 60, the efficiency score (accuracy divided by reaction time) reached a peak in the 20-27 age range and then declined with increasing age. Importantly, schizophrenia patients failed to display this developmental trend in the same age range and adults had significant deficits compared to the control group. Our data suggests that this simple Spatial Working Memory and Attention Test on Paired Symbols can be a useful tool for studies of spatial working memory and attention in neuropsychiatric disorders.


Asunto(s)
Atención/fisiología , Discapacidades del Desarrollo/psicología , Memoria a Corto Plazo/fisiología , Pruebas Neuropsicológicas , Psicología del Esquizofrénico , Percepción Espacial/fisiología , Adolescente , Adulto , Envejecimiento/psicología , Pueblo Asiatico , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Desempeño Psicomotor/fisiología , Esquizofrenia , Adulto Joven
12.
Ergonomics ; 56(8): 1225-31, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23789793

RESUMEN

Accurate evaluation of emergencies is a critical concern in long-duration space flights. Accordingly, we studied the effect of 45 days of - 6° head-down bed rest - a model that simulates the conditions in microgravity environments - on the evaluation of orally reported emergencies. Sixteen male participants listened to corresponding emergency scenarios and assessed the severity of these situations eight times before, during and after bed rest. The results revealed a ' recency effect': compared with emergency descriptions in the order of serious to mild, those framed in the reverse order were judged to be more serious. However, the severity ratings did not vary with time spent in the simulated microgravity environment. These findings are similar to those observed in a regular environment on Earth, indicating that the design principles of information presentation for situations on Earth may also be extended to designs intended for outer space. PRACTITIONER SUMMARY: A recency effect was found in the evaluation of orally reported emergencies under simulated microgravity conditions. The design principles of information presentation for situations on Earth may also be extended to designs intended for outer space.


Asunto(s)
Comunicación , Urgencias Médicas/psicología , Juicio , Simulación de Ingravidez/psicología , Adulto , Inclinación de Cabeza , Humanos , Masculino , Tiempo de Reacción , Factores de Tiempo , Adulto Joven
13.
IEEE Trans Biomed Eng ; 70(5): 1454-1461, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36306313

RESUMEN

OBJECTIVE: Electroencephalography (EEG) is one of the functional brain imaging techniques to effectively measure neuronal activity, but its low spatial resolution makes it difficult to localize evoked excitatory neurons or areas of abnormal firing. Multimodal imaging techniques are expected to combine the high spatial resolution (mm level) of focused ultrasound (FUS) with the high temporal resolution (ms level) of EEG. The technique must be performed under the premise that ultrasound stimulation does not affect neuronal firing, and there is an urgent need to determine the threshold of this ultrasound stimulation parameter. METHODS: In this paper, the subthalamic nucleus neuronal firing model and the bilayer sonophore model are combined to numerically simulate the neuronal firing rhythm under the conditions of different stimulation parameters. The correlation and frequency differences of neuronal firing rhythms with and without ultrasound stimulation were compared and used as an index to evaluate the degree of change, and the final range of effective threshold parameters for ultrasound stimulation of neurons but not inducing neuronal firing was obtained. RESULTS: The results showed that the correlation of neuronal firing rhythms in both conditions with and without stimulation decreased and the frequency difference increased with increasing ultrasound parameters such as duty cycle, intensity, center frequency and pulse repetition frequency. CONCLUSION: An effective range of stimulation threshold parameters can be obtained based on the correlation coefficients and frequency difference matrices under different parameter combinations. SIGNIFICANCE: The threshold can further promote the safe and effective application of FUS for multimodal electrophysiological imaging.


Asunto(s)
Núcleo Subtalámico , Núcleo Subtalámico/fisiología , Neuronas/fisiología , Potenciales de Acción/fisiología
14.
Front Pharmacol ; 14: 1173920, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37205911

RESUMEN

In aerospace medicine, the influence of microgravity on cognition has always been a risk factor threatening astronauts' health. The traditional medicinal plant and food material Gastrodia elata Blume has been used as a therapeutic drug for neurological diseases for a long time due to its unique neuroprotective effect. To study the effect of fresh Gastrodia elata Blume (FG) on cognitive impairment caused by microgravity, hindlimb unloading (HU) was used to stimulate weightlessness in mice. The fresh Gastrodia elata Blume (0.5 g/kg or 1.0 g/kg) was intragastrically administered daily to mice exposed to HU and behavioral tests were conducted after four weeks to detect the cognitive status of animals. The behavioral tests results showed that fresh Gastrodia elata Blume therapy significantly improved the performance of mice in the object location recognition test, Step-Down test, and Morris Water Maze test, including short-term and long-term spatial memory. According to the biochemical test results, fresh Gastrodia elata Blume administration not only reduced serum factor levels of oxidative stress but also maintained the balance of pro-inflammatory and anti-inflammatory factors in the hippocampus, reversing the abnormal increase of NLRP3 and NF-κB. The apoptosis-related proteins were downregulated which may be related to the activation of the PI3K/AKT/mTOR pathway by fresh Gastrodia elata Blume therapy, and the abnormal changes of synapse-related protein and glutamate neurotransmitter were corrected. These results identify the improvement effect of fresh Gastrodia elata Blume as a new application form of Gastrodia elata Blume on cognitive impairment caused by simulated weightlessness and advance our understanding of the mechanism of fresh Gastrodia elata Blume on the neuroprotective effect.

15.
Front Neurosci ; 16: 807376, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35924223

RESUMEN

Neuroimaging can help reveal the spatial and temporal diversity of neural activity, which is of utmost importance for understanding the brain. However, conventional non-invasive neuroimaging methods do not have the advantage of high temporal and spatial resolution, which greatly hinders clinical and basic research. The acoustoelectric (AE) effect is a fundamental physical phenomenon based on the change of dielectric conductivity that has recently received much attention in the field of biomedical imaging. Based on the AE effect, a new imaging method for the biological current source has been proposed, combining the advantages of high temporal resolution of electrical measurements and high spatial resolution of focused ultrasound. This paper first describes the mechanism of the AE effect and the principle of the current source imaging method based on the AE effect. The second part summarizes the research progress of this current source imaging method in brain neurons, guided brain therapy, and heart. Finally, we discuss the problems and future directions of this biological current source imaging method. This review explores the relevant research literature and provides an informative reference for this potential non-invasive neuroimaging method.

16.
PLoS One ; 17(8): e0272118, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35921380

RESUMEN

In this paper, an aliasing noise restraint technique and a system identification-based surface electromyography (sEMG)-force prediction model are proposed to realize a type of robust sEMG and muscle force prediction. For signal denoising, a novel non-negative matrix factorization screening empirical mode decomposition (NMFSEMD) and a fast orthogonal search (FOS)-based muscle force prediction model are developed. First, the NMFSEMD model is used to screen the empirical mode decomposition (EMD) results into the noisy intrinsic mode functions (IMF). Then, the noise matrix is computed using IMF translation and superposition, and the matrix is used as the input of NMF to obtain the denoised IMF. Furthermore, the reconstruction outcome of the NMFSEMD method can be used to estimate the denoised sEMG. Finally, a new sEMG muscle force prediction model, which considers a kind of candidate function in derivative form, is constructed, and a data-training-based linear weighted model is obtained. Extensive experimental results validate the suggested method's correction: after the NMFSEMD denoising of raw sEMG signal, the signal-noise ratio (SNR) can be improved by about 15.0 dB, and the energy percentage (EP) can be greater than 90.0%. Comparing with the muscle force prediction models using the traditional pretreatment and LSSVM, and the NMFSEMD plus LSSVM-based method, the mean square error (MSE) of our approach can be reduced by at least 1.2%.


Asunto(s)
Algoritmos , Procesamiento de Señales Asistido por Computador , Electromiografía/métodos , Músculos , Relación Señal-Ruido
17.
J Neural Eng ; 19(2)2022 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-35468593

RESUMEN

Objective. Electroencephalography is a technique for measuring normal or abnormal neuronal activity in the human brain, but its low spatial resolution makes it difficult to locate the precise locations of neurons due to the volume conduction effect of brain tissue.Approach. The acoustoelectric (AE) effect has the advantage of detecting electrical signals with high temporal resolution and focused ultrasound with high spatial resolution. In this paper, we use dipoles to simulate real single and double neurons, and further investigate the localization and decoding of single and double dipoles based on AE effects from numerical simulations, brain tissue phantom experiments, and fresh porcine brain tissue experiments.Main results. The results show that the localization error of a single dipole is less than 0.3 mm, the decoding signal is highly correlated with the source signal, and the decoding accuracy is greater than 0.94; the location of double dipoles with an interval of 0.4 mm or more can be localized, the localization error tends to increase as the interval of dipoles decreases, and the decoding accuracy tends to decrease as the frequency of dipoles decreases.Significance. This study localizes and decodes dipole signals with high accuracy, and provides a technical method for the development of EEG.


Asunto(s)
Encéfalo , Electroencefalografía , Animales , Encéfalo/fisiología , Mapeo Encefálico/métodos , Simulación por Computador , Electroencefalografía/métodos , Cabeza , Porcinos
18.
Nat Commun ; 13(1): 2765, 2022 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-35589705

RESUMEN

The human visual perceptual system is highly sensitive to biological motion (BM) but less sensitive to its inverted counterpart. This perceptual inversion effect may stem from our selective sensitivity to gravity-constrained life motion signals and confer an adaptive advantage to creatures living on Earth. However, to what extent and how such selective sensitivity is shaped by the Earth's gravitational field is heretofore unexplored. Taking advantage of a spaceflight experiment and its ground-based analog via 6° head-down tilt bed rest (HDTBR), we show that prolonged microgravity/HDTBR reduces the inversion effect in BM perception. No such change occurs for face perception, highlighting the particular role of gravity in regulating kinematic motion analysis. Moreover, the reduced BM inversion effect is associated with attenuated orientation-dependent neural responses to BM rather than general motion cues and correlated with strengthened functional connectivity between cortical regions dedicated to visual BM processing (i.e., pSTS) and vestibular gravity estimation (i.e., insula). These findings suggest that the neural computation of gravity may act as an embodied constraint, presumably implemented through visuo-vestibular interaction, to sustain the human brain's selective tuning to life motion signals.


Asunto(s)
Percepción de Movimiento , Vestíbulo del Laberinto , Gravitación , Humanos , Movimiento (Física) , Percepción de Movimiento/fisiología , Vestíbulo del Laberinto/fisiología , Percepción Visual
19.
PLoS One ; 16(9): e0257230, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34547014

RESUMEN

Named entity recognition (NER) is one fundamental task in the natural language processing (NLP) community. Supervised neural network models based on contextualized word representations can achieve highly-competitive performance, which requires a large-scale manually-annotated corpus for training. While for the resource-scarce languages, the construction of such as corpus is always expensive and time-consuming. Thus, unsupervised cross-lingual transfer is one good solution to address the problem. In this work, we investigate the unsupervised cross-lingual NER with model transfer based on contextualized word representations, which greatly advances the cross-lingual NER performance. We study several model transfer settings of the unsupervised cross-lingual NER, including (1) different types of the pretrained transformer-based language models as input, (2) the exploration strategies of the multilingual contextualized word representations, and (3) multi-source adaption. In particular, we propose an adapter-based word representation method combining with parameter generation network (PGN) better to capture the relationship between the source and target languages. We conduct experiments on a benchmark ConLL dataset involving four languages to simulate the cross-lingual setting. Results show that we can obtain highly-competitive performance by cross-lingual model transfer. In particular, our proposed adapter-based PGN model can lead to significant improvements for cross-lingual NER.


Asunto(s)
Lenguaje , Lingüística , Multilingüismo , Procesamiento de Lenguaje Natural , Redes Neurales de la Computación , Algoritmos , Benchmarking , Humanos , Nombres , Reconocimiento en Psicología , Semántica
20.
Front Psychiatry ; 12: 596017, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35126189

RESUMEN

Chronic sleep deprivation (SD) causes neurological and neurodegenerative dysfunction including learning and memory deficit. The orchid Dendrobium nobile Lindl (DNL), is widely used as a Yin tonic and medicinal food throughout Asia, and has many reported pharmacological effects. This study focused on the cognitive-enhancing effects of DNL in sleep deprivation-induced amnesia in mice and its biochemical mechanisms. Our results showed that the mice displayed significant cognitive deficits after 2-week SD while treatment with the extract of DNL prevented these impairments. In the novel object recognition and object location recognition tasks, a significant increase in the discrimination index was observed in DNL-treated (200 and 400 mg/kg) mice. In the MWM test, DNL (200 and 400 mg/kg) treatment shorten the prolongation of latency and increased the crossing numbers compared with SD mice. The biochemical analysis of brain tissue showed a decrease in NE, dismutase (T-SOD) and catalase (CAT) activity and an increase in 5-HT and malondialdehyde (MDA) concentration after the treatment with DNL in mice. Our findings indicated that DNL exerted a positive effect in preventing and improving cognitive impairment induced by SD, which may be mediated via the regulation of neurotransmitters and alleviation of oxidative stress.

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