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1.
J Neural Eng ; 18(5)2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33761480

RESUMO

Objective. Development of a brain-computer interface (BCI) requires classification of brain neural activities to different states. Functional near-infrared spectroscopy (fNIRS) can measure the brain activities and has great potential for BCI. In recent years, a large number of classification algorithms have been proposed, in which deep learning methods, especially convolutional neural network (CNN) methods are successful. fNIRS signal has typical time series properties, we combined fNIRS data and kinds of CNN-based time series classification (TSC) methods to classify BCI task.Approach. In this study, participants were recruited for a left and right hand motor imagery experiment and the cerebral neural activities were recorded by fNIRS equipment (FOIRE-3000). TSC methods are used to distinguish the brain activities when imagining the left or right hand. We have tested the overall person, single person and overall person with single-channel classification results, and these methods achieved excellent classification results. We also compared the CNN-based TSC methods with traditional classification methods such as support vector machine.Main results. Experiments showed that the CNN-based methods have significant advantages in classification accuracy: the CNN-based methods have achieved remarkable results in the classification of left-handed and right-handed imagination tasks, reaching 98.6% accuracy on overall person, 100% accuracy on single person, and in the single-channel classification an accuracy of 80.1% has been achieved with the best-performing channel.Significance. These results suggest that using the CNN-based TSC methods can significantly improve the BCI performance and also lay the foundation for the miniaturization and portability of training rehabilitation equipment.


Assuntos
Interfaces Cérebro-Computador , Eletroencefalografia , Humanos , Imaginação , Redes Neurais de Computação , Espectroscopia de Luz Próxima ao Infravermelho
2.
Am Surg ; 87(6): 927-932, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33284051

RESUMO

Perianal abscess and anal fistula are 2 common anorectal diseases in infants and young children. However, their causes, clinical diagnosis, and treatment remain controversial. Compared to adults, infants with these 2 diseases exhibit unique clinical characteristics. Blind pursuit of conservative treatment or surgery may worsen the condition, resulting in increased pain in young patients and greater economic burden and psychological harm to parents. Therefore, it is crucial to select correct and effective treatments. This review summarizes the relevant literature from the past 10 years and systematically explains the pathogenesis, clinical characteristics, and treatment measures of perianal abscess and anal fistula in infants with the goal of providing clinicians a deeper understanding of perianal abscess and anal fistula in infants and summarizing safe and effective treatment methods.


Assuntos
Abscesso/cirurgia , Doenças do Ânus/cirurgia , Fístula Retal/cirurgia , Abscesso/congênito , Doenças do Ânus/congênito , Criança , Pré-Escolar , Humanos , Lactente , Recém-Nascido , Fístula Retal/congênito
3.
Opt Express ; 23(15): 20115-23, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26367669

RESUMO

A bendable ultra-black material consisting of graphite nanocones and nanowires is fabricated through a simple plasma etching process. The optical properties of the absorber are characterized in the wavelength range of 400-2000 nm with average specular reflectance 0.05 ± 0.03% at normal incidence and the material thickness is only around 5 µm. The reflectance of the absorber remains low at large incident angles and is relatively independent of polarization. Simulations confirm the cooperative effect of the nanowires and nanocones leading to an ultra-black thin carbon material.

4.
Phys Rev Lett ; 110(18): 187802, 2013 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-23683245

RESUMO

Active elastomeric liquid crystal particles with initial cylindrical shapes are obtained by means of soft lithography and polymerization in a strong magnetic field. Gold nanocrystals infiltrated into these particles mediate energy transfer from laser light to heat, so that the inherent coupling between the temperature-dependent order and shape allows for dynamic morphing of these particles and well-controlled stable shapes. Continuous changes of particle shapes are followed by their spontaneous realignment and transformations of director structures in the surrounding cholesteric host, as well as locomotion in the case of a nonreciprocal shape morphing. These findings bridge the fields of liquid crystal solids and active colloids, may enable shape-controlled self-assembly of adaptive composites and light-driven micromachines, and can be understood by employing simple symmetry considerations along with electrostatic analogies.


Assuntos
Colesterol/química , Coloides/química , Cristais Líquidos/química , Elastômeros/química , Ouro/química , Nanopartículas Metálicas/química
5.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(12): 3188-92, 2012 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-23427532

RESUMO

During the preparation of amino phosphoric chelating fiber, polypropylene grafted styrene, acetyl, amine series and amino phosphonic acid chelating fibers were certified by infrared spectrum, and the functionalization degree of raw fibers was studied. By the semi-qualitative method of infrared spectrum, the adsorption performance of indium and copper on amino phosphonic chelating fiber was also discussed. The results showed that (1) The peak at 1 116 cm(-1) was assigned to--P(ONa)2 in amino phosphonic acid chelating fiber. So the success of phosphorylation was verified. (2) During preparation, the phosphorylation effect of amino phosphonic acid chelating fiber could be reflected by the change of the peaks at 1 056 and 1 110 cm(-)1. (3) After adsorption of In3+ on amino phosphonic acid chelating fiber, the new forming N-In coordination key was absorbed strongly at the bands of 1 000-1 200 cm(-1) and at 1 107, 699 and 617 cm(-1). After adsorption Cu2+ on amino phosphonic acid chelating fiber two new strong and wide peaks were found at 1 110 and 618 cm(-1), respectively. (4) Through the area change of the bands at 1 200-900 and 600 cm(-1), the adsorption performance of indium and copper on amino phosphonic acid chelating fiber was compared.

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