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1.
Worldviews Evid Based Nurs ; 20(6): 593-609, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37526252

RESUMO

BACKGROUND: As pharmacotherapy often leads to adverse reactions, mind-body exercise (MBE) treatments have become a more popular option for treating depression in people living with breast cancer (BC). However, the most effective type of MBE treatment for this population remains unclear. AIMS: The aim of this systematic review and network meta-analysis (NMA) was to compare the efficacy of the different MBE modes for depression in people with BC. METHODS: A systematic search for randomized controlled trials (RCTs) from inception to March 25, 2023, was conducted in the following database: EMBASE, PubMed, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Wanfang Data, China Biology Medicine, OpenGrey, and ClinicalTrials.gov. A traditional meta-analysis was conducted using the random-effects model to directly assess the effectiveness of various MBE interventions. Stata 16.0 software was used for performing the NMA. RESULTS: The NMA was performed in 32 eligible RCTs including 2361 participants. The efficacy of MBE treatments on depression was ranked as the following: Liuzijue (surface under the cumulative ranking curve [SUCRA] = 95.4%) > Tai chi (SUCRA = 76.9%) > yoga (SUCRA = 55.0%) > Baduanjin (SUCRA = 53.9%) > Pilates (SUCRA = 38.6%) > dance (SUCRA = 30.2%) > Qigong (SUCRA = 28.1%) > control (SUCRA = 21.9%). LINKING EVIDENCE TO ACTION: Our research showed that Liuzijue and Tai chi might be the most significantly effective MBE intervention for mitigating depression among BC survivors. Healthcare professionals could consider recommending Liuzijue and Tai Chi as a complementary therapy for BC survivors who experience depression.


Assuntos
Neoplasias da Mama , Sobreviventes de Câncer , Humanos , Feminino , Metanálise em Rede , Depressão/terapia , Neoplasias da Mama/complicações , Neoplasias da Mama/terapia , Sobreviventes
2.
Opt Express ; 30(2): 2143-2155, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209361

RESUMO

Based on the full wave simulation and the Maxwell stress tensor theory, we demonstrate an enhanced transverse optical gradient force acting on Rayleigh particles immersed in a simple optical field formed by two linearly polarized plane waves. The optical gradient force acting on a conventional dielectric particle can be enhanced by two orders of magnitude via coating an extremely thin silver shell, whose thickness is only about one-tenth of the dielectric core. The analytical results based on the multipole expansion theory reveal that the enhanced optical gradient force comes mostly from the interaction between the incident field and the electric quadrupole excited in the core-shell particle. It is worth noting that the force expression within the dipole approximation commonly used for Rayleigh particles is invalid in our situation, even the particle is within the Rayleigh regime. In addition, both the optical potential energy and the optical trapping stiffness for the core-shell particle exhibit a great enhancement by two orders of magnitude stronger than a conventional dielectric particle and thus is favorable to a stable optical trapping. These results may extend the application range of optical tweezers and enrich optical manipulation techniques.

3.
J Clin Nurs ; 31(11-12): 1488-1501, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34888968

RESUMO

AIMS AND OBJECTIVES: To evaluate the effectiveness of family-based intervention for adults with diabetes on glycosylated haemoglobin and other health-related outcomes. BACKGROUND: The impact of family-based intervention on adults with diabetes has been evaluated in various studies, but there is uncertainty about their effect on health-related outcomes for adults with diabetes. DESIGN: A systematic review and meta-analysis of randomised controlled trials. METHODS: A review was performed and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Six relevant databases were searched from inception to 5 March 2021. Heterogeneity between studies was quantified by using Higgins' I2 test. Sensibility and subgroup analyses were used to explore potential heterogeneity. RESULTS: The review included 23 studies (3,114 participants). Family-based intervention had a significant effect on improving glycosylated haemoglobin levels, body mass index, blood pressure, fasting glucose, diabetes self-care, diabetes self-efficacy, diabetes distress and positive family support. Non-significant results were obtained for blood lipid, body weight, depression and negative family support. In particular, subgroup analyses indicated that family-based intervention in Asian regions was more effective in improving glycosylated haemoglobin levels than in other areas. CONCLUSION: Family-based intervention may improve diabetes control, diabetes self-care, psychological well-being and positive family support in adults with diabetes and is especially effective in Asian regions. Given the limitations in current studies, further studies are recommended to combine family theory with family-based intervention, and to examine the effectiveness of such intervention for family members. RELEVANCE TO CLINICAL PRACTICE: This review and meta-analysis provides evidence that family-based intervention can improve positive family support, which has a good effect on diabetes control and psychological well-being in adults with diabetes, and it is especially effective in Asian regions. Findings suggested that unreinforced participation by family members and integrating flexible strategies into family-based intervention may be equally effective.


Assuntos
Diabetes Mellitus Tipo 2 , Adulto , Índice de Massa Corporal , Diabetes Mellitus Tipo 2/psicologia , Hemoglobinas Glicadas , Humanos , Autocuidado , Autoeficácia
4.
J Nurs Manag ; 30(8): 4251-4261, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36205051

RESUMO

AIMS: To investigate the relationship between organizational support and nurse managers' burnout and the serial multiple mediating effects of leadership and resilience. BACKGROUND: Nurse managers are at a high risk of burnout, especially during the COVID-19 pandemic. However, no research has been done to examine the associations between nurse managers' organizational support, leadership, resilience and burnout. METHODS: This cross-sectional study recruited 458 nurse managers from 13 tertiary public hospitals in Jiangsu, China. They completed the Survey of Perceived Organizational Support, the Clinical Leadership Survey, the Resilience Scale and the Maslach Burnout Inventor-Human Service Survey. The serial mediating effect of individual leadership and resilience was estimated using the structural equation modelling method via Mplus 7.0. RESULTS: There were direct and indirect effects of organizational support on burnout, controlling for work variables. Leadership and resilience serially mediate the association between organizational support and burnout (ß = -.051, 95% confidence interval: -0.093 to -0.020). CONCLUSIONS: Among nurse managers, organizational support may be sequentially associated with improved leadership first and then resilience, which in turn is related to decreased burnout. IMPLICATIONS FOR NURSING MANAGEMENT: We recommend that hospital administrators incorporate leadership, resilience and burnout assessment in the routine psychological screening of nurse managers and creatively apply the organizational interventions to decrease nurse managers' burnout.


Assuntos
Esgotamento Profissional , COVID-19 , Enfermeiros Administradores , Humanos , Liderança , Enfermeiros Administradores/psicologia , Estudos Transversais , Pandemias , COVID-19/epidemiologia , Esgotamento Profissional/etiologia , Esgotamento Profissional/prevenção & controle , Esgotamento Profissional/psicologia , Inquéritos e Questionários
5.
J Am Chem Soc ; 143(20): 7759-7768, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-33904710

RESUMO

Low-work-function (WF) metals (including silver (Ag), aluminum (Al), and copper (Cu)) used as external cathodes in inverted perovskite solar cells (PSCs) encounter oxidation caused by air exposure and halogen-diffusion-induced corrosion, which threaten the long-term stability of the device. The cathode interlayer (CIL) has shown promise in reducing the metal WF and thus boosting the device power conversion efficiency (PCE). However, it remains a challenge for current CIL materials to enable high-WF metals (e.g., Au) to be used as cathodes to achieve PSCs with a superior PCE and long-term stability. Here, we use a series of synthesized (carbolong-derived) organometallic complexes as CILs to tune the electrode WF in inverted PSCs. Density functional theory calculations and surface characterizations show that the organometallic complexes that contain anions and cations are prone to form anion-cation dipoles on the metal surface, hence drastically reducing the metal's WF. Photovoltaic devices based on a Ag cathode, which was modified with these organometallic complexes, received a boosted PCE up to 21.29% and a remarkable fill factor that reached 83.52%, which are attributed to the dipole-enhanced carrier transport. The environmental stability of PSCs was further improved after employing Au as a cathode with these organometallic complexes, and the modified devices exhibited no efficiency loss after 4080 h storage measurements.

6.
J Org Chem ; 86(11): 7370-7380, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34014083

RESUMO

A Rh(III)-catalyzed cascade nucleophilic addition/intramolecular annulation of 2-diazo-1,3-diketones with 1,3-dicarbonyl compounds (e.g., 1,3-diketones and ß-keto esters) is achieved to afford 6,7-dihydrobenzofuran-4(5H)-ones in up to 91% yields. Notably, a wide range of substrates and functional groups were well-tolerated under the optimized reaction conditions to give desired products in moderate to excellent yields with release of N2 and H2O as byproducts. Moreover, the method described is scalable and adaptable to late-stage functionalization.

7.
J Org Chem ; 86(5): 4182-4192, 2021 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-33625853

RESUMO

A novel and versatile approach to construct 12-phenacyl-11H-benzo[b]xanthene-6,11(12H)-dione derivatives through copper-catalyzed cascade reaction of propargylamines with 2-hydroxynaphthalene-1,4-diones has been developed. The procedure is proposed to go through a sequence of 1,4-conjugate addition, intramolecular nucleophilic addition/dehydration, and hydrolysis of alkyne followed by an enol-ketone tautomerization. The reaction provides a new and highly efficient method for the synthesis of 12-phenacyl-11H-benzo[b]xanthene-6,11(12H)-diones by formation of three new bonds and one heterocycle from readily available starting materials in good to high yields (70-88%) with broad functional group compatibility in a single step.


Assuntos
Cobre , Xantenos , Catálise , Hidrólise , Naftóis , Pargilina/análogos & derivados , Propilaminas
8.
J Clin Nurs ; 30(13-14): 1884-1892, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33656212

RESUMO

AIMS AND OBJECTIVES: To determine whether resilience buffers the deleterious consequences of caregiver burden on quality of life among parents of children with type 1 diabetes. BACKGROUND: The burden of caring for a child with type 1 diabetes can be a form of stress and damage parents' quality of life. Resilience is a crucial psychological variable that contributes to individual health in the context of extraordinary challenges. However, no studies in paediatric diabetes have focused on the effects of parent resilience on caregiving burden and quality of life. DESIGN: This was a descriptive cross-sectional study with a convenience sample following the STROBE guidelines. METHODS: A total of 227 parents were invited to participate during the children's routine outpatient visit. Parents completed measures of resilience, caregiver burden and quality of life. The disease characteristics of children were extracted from the electronic medical records. We performed hierarchical multiple regression and Johnson-Neyman statistical analysis to probe the moderating effect of resilience. RESULTS: The parents reported poorer mental and physical health as compared with the general population. Caregiver burden was significantly negatively associated with parents' quality of life, while resilience demonstrated a positive correlation with life quality. Resilience served as a moderator between caregiver burden and mental health. When parents experienced a high caregiver burden, the benefit of high resilience for better mental health was apparent. CONCLUSIONS: The present study underscores the protective role of resilience in reducing caregiving burden and improving parents' quality of life. RELEVANCE TO CLINICAL PRACTICE: Regular psychosocial assessment for parents of children with type 1 diabetes should be incorporated into clinical nursing practice. This study confirms that resilience is a promising intervention target for parents with heavy caregiver burden and unsatisfactory life quality.


Assuntos
Diabetes Mellitus Tipo 1 , Qualidade de Vida , Sobrecarga do Cuidador , Cuidadores , Criança , Estudos Transversais , Humanos , Pais
9.
Org Biomol Chem ; 18(15): 2893-2901, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32236225

RESUMO

A novel and mild Rh(iii)-catalyzed C-H activation/intramolecular condensation of 1-aryl-1H-pyrazol-5-amines with cyclic 2-diazo-1,3-diketones was developed, giving access to various important benzo[f]pyrazolo[1,5-a][1,3]diazepine scaffolds through sequential C-C/C-N bond formation in a one-pot procedure under additive- and oxidant-free conditions. Furthermore, 3-([1,1'-biphenyl]-2-ylamino)-2-ethoxycyclohex-2-enones can be obtained in good yields by constructing C-O and C-N bonds through 1,1'-insertion, dehydration, and isomerization processes.

10.
Org Biomol Chem ; 18(22): 4178-4182, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32441722

RESUMO

A novel and efficient multicomponent reaction of cyclic 2-diazo-1,3-diketones, carbodiimides, and 1,2-dihaloethanes has been developed, and it leads to unsymmetrical urea derivatives with good yields in a single operation. This transformation involves the cascade formation of C-X (X = Cl, Br, I), C-N and C[double bond, length as m-dash]O bonds through halogenation, nucleophilic addition, ring-opening, and enol-ketone tautomerization processes. This protocol is step- and atom-economical; 1,2-dihaloethane was used as an easily available halogenated reagent, and it is amenable to different functional groups.

11.
J Org Chem ; 84(18): 11623-11638, 2019 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-31433637

RESUMO

A simple, general route to the 2,3-dihydrobenzofurans substituted at C3 by an aryethynyl or aryl group, starting from propargylamine and its derivatives with benzoyl sulfonium salts, has been developed. This reaction involved an in situ generated o-quinone methide (o-QM) intermediate followed by [4+1] annulation with sulfur ylides. Notably, this protocol's features include moderate to excellent yields and remarkable diastereoselectivity (>20:1 dr in general), easy performance, as well as applicability to versatile 2,3-dihydrobenzofurans with aryethynyl or an aryl group via C-C and C-O bond formation in one pot without any catalyst in an aqueous mixed solvent.

12.
Front Neurosci ; 18: 1367932, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38660227

RESUMO

Steady-state visual evoked potential brain-computer interfaces (SSVEP-BCI) have attracted significant attention due to their ease of deployment and high performance in terms of information transfer rate (ITR) and accuracy, making them a promising candidate for integration with consumer electronics devices. However, as SSVEP characteristics are directly associated with visual stimulus attributes, the influence of stereoscopic vision on SSVEP as a critical visual attribute has yet to be fully explored. Meanwhile, the promising combination of virtual reality (VR) devices and BCI applications is hampered by the significant disparity between VR environments and traditional 2D displays. This is not only due to the fact that screen-based SSVEP generally operates under static, stable conditions with simple and unvaried visual stimuli but also because conventional luminance-modulated stimuli can quickly induce visual fatigue. This study attempts to address these research gaps by designing SSVEP paradigms with stereo-related attributes and conducting a comparative analysis with the traditional 2D planar paradigm under the same VR environment. This study proposed two new paradigms: the 3D paradigm and the 3D-Blink paradigm. The 3D paradigm induces SSVEP by modulating the luminance of spherical targets, while the 3D-Blink paradigm employs modulation of the spheres' opacity instead. The results of offline 4-object selection experiments showed that the accuracy of 3D and 2D paradigm was 85.67 and 86.17% with canonical correlation analysis (CCA) and 86.17 and 91.73% with filter bank canonical correlation analysis (FBCCA), which is consistent with the reduction in the signal-to-noise ratio (SNR) of SSVEP harmonics for the 3D paradigm observed in the frequency-domain analysis. The 3D-Blink paradigm achieved 75.00% of detection accuracy and 27.02 bits/min of ITR with 0.8 seconds of stimulus time and task-related component analysis (TRCA) algorithm, demonstrating its effectiveness. These findings demonstrate that the 3D and 3D-Blink paradigms supported by VR can achieve improved user comfort and satisfactory performance, while further algorithmic optimization and feature analysis are required for the stereo-related paradigms. In conclusion, this study contributes to a deeper understanding of the impact of binocular stereoscopic vision mechanisms on SSVEP paradigms and promotes the application of SSVEP-BCI in diverse VR environments.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38648157

RESUMO

As an essential cognitive function, attention has been widely studied and various indices based on EEG have been proposed for its convenience and easy availability for real-time attention monitoring. Although existing indices based on spectral power of empirical frequency bands are able to describe the attentional state in some way, the reliability still needs to be improved. This paper proposed a subject-specific attention index based on the weighted spectral power. Unlike traditional indices, the ranges of frequency bands are not empirical but obtained from subject-specific change patterns of spectral power of electroencephalograph (EEG) to overcome the great inter-subject variance. In addition, the contribution of each frequency component in the frequency band is considered different. Specifically, the ratio of power spectral density (PSD) function in attentional and inattentional state is utilized to calculate the weight to enhance the effectiveness of the proposed index. The proposed subject-specific attention index based on the weighted spectral power is evaluated on two open datasets including EEG data of a total of 44 subjects. The results of the proposed index are compared with 3 traditional attention indices using various statistical analysis methods including significance tests and distribution variance measurements. According to the experimental results, the proposed index can describe the attentional state more accurately. The proposed index respectively achieves accuracies of 86.21% and 70.00% at the 1% significance level in both the t-test and Wilcoxon rank-sum test for two datasets, which obtains improvements of 41.38% and 20.00% compared to the best result of the traditional indices. These results indicate that the proposed index provides an efficient way to measure attentional state.


Assuntos
Algoritmos , Atenção , Eletroencefalografia , Humanos , Atenção/fisiologia , Eletroencefalografia/métodos , Reprodutibilidade dos Testes , Masculino , Feminino , Adulto , Adulto Jovem
14.
Artigo em Inglês | MEDLINE | ID: mdl-38758616

RESUMO

Brain-computer interfaces (BCIs) have been widely focused and extensively studied in recent years for their huge prospect of medical rehabilitation and commercial applications. Transfer learning exploits the information in the source domain and applies in another different but related domain (target domain), and is therefore introduced into the BCIs to figure out the inter-subject variances of electroencephalography (EEG) signals. In this article, a novel transfer learning method is proposed to preserve the Riemannian locality of data structure in both the source and target domains and simultaneously realize the joint distribution adaptation of both domains to enhance the effectiveness of transfer learning. Specifically, a Riemannian graph is first defined and constructed based on the Riemannian distance to represent the Riemannian geometry information. To simultaneously align the marginal and conditional distribution of source and target domains and preserve the Riemannian locality of data structure in both domains, the Riemannian graph is embedded in the joint distribution adaptation (JDA) framework and forms the proposed Riemannian locality preserving-based transfer learning (RLPTL). To validate the effect of the proposed method, it is compared with several existing methods on two open motor imagery datasets, and both multi-source domains (MSD) and single-source domains (SSD) experiments are considered. Experimental results show that the proposed method achieves the highest accuracies in MSD and SSD experiments on three datasets and outperforms eight baseline methods, which demonstrates that the proposed method creates a feasible and efficient way to realize transfer learning.

15.
Micromachines (Basel) ; 14(6)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37374724

RESUMO

In this paper, a dual-polarized Huygens unit is proposed, which has a double-layer metallic pattern etched on both sides of one dielectric substrate. Induced magnetism enables the structure to support Huygens' resonance, thus obtaining nearly complete available transmission phase coverage. By optimizing the structural parameters, a better transmission performance can be achieved. When the Huygens metasurface was used for the design of a meta-lens, good radiation performance was exhibited, with a maximum gain of 31.15 dBi at 28 GHz, an aperture efficiency of 42.7% and a 3 dB gain bandwidth of 26.4 GHz to 30 GHz (12.86%). Due to its excellent radiation performance and very simple fabrication, this Huygens meta-lens has important applications in millimeter-wave communication systems.

16.
Nanomaterials (Basel) ; 13(24)2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38133031

RESUMO

Perovskites have been recognized as a class of promising materials for optoelectronic devices. We intentionally include excessive Cs+ cations in precursors in the synthesis of perovskite CsPbBr3 nanocrystals and investigate how the Cs+ cations influence the lattice strain in these perovskite nanocrystals. Upon light illumination, the lattice strain due to the addition of alkali metal Cs+ cations can be compensated by light-induced lattice expansion. When the Cs+ cation in precursors is about 10% excessive, the electron-phonon coupling strength can be reduced by about 70%, and the carrier cooling can be slowed down about 3.5 times in lead halide perovskite CsPbBr3 nanocrystals. This work reveals a new understanding of the role of Cs+ cations, which take the A-site in ABX3 perovskite and provide a new way to improve the performance of perovskites and their practical devices further.

17.
Biol Res Nurs ; 25(1): 41-50, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35839096

RESUMO

OBJECTIVE: To systematically summarize the reported prediction models for hypoglycemia in patients with diabetes, compare their performance, and evaluate their applicability in clinical practice. METHODS: We selected studies according to the PRISMA, appraised studies according to the Prediction model Risk of Bias Assessment Tool (PROBAST), and extracted and synthesized the data according to the CHARMS. The databases of PubMed, Web of Science, Embase, and Cochrane Library were searched from inception to 31 October 2021 using a systematic review approach to capture all eligible studies developing and/or validating a prognostic prediction model for hypoglycemia in patients with diabetes. The risk bias and clinical applicability were assessed using the PROBAST. The meta-analysis of the performance of the prediction models were also conducted. The protocol of this study was recorded in PROSPERO (CRD42022309852). RESULTS: Sixteen studies with 22 models met the eligible criteria. The predictors with the high frequency of occurrence among all models were age, HbA1c, history of hypoglycemia, and insulin use. A meta-analysis of C-statistic was performed for 21 prediction models, and the summary C-statistic and its 95% confidence interval and prediction interval were 0.7699 (0.7299-0.8098), 0.7699 (0.5862-0.9536), respectively. Heterogeneity exists between different hypoglycemia prediction models (τ2 was 0.00734≠0). CONCLUSIONS: The existing predictive models are not recommended for widespread clinical use. A high-quality hypoglycemia screening tool should be developed in future studies.


Assuntos
Diabetes Mellitus , Humanos , Medição de Risco , Previsões
18.
J Neural Eng ; 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36808912

RESUMO

OBJECTIVE: Visual evoked potentials (VEPs) have been commonly applied in brain-computer interfaces (BCIs) due to their satisfactory classification performance recently. However, most existing methods with flickering or oscillating stimuli will induce visual fatigue under long-term training, thus restricting the implementation of VEP-based BCIs. To address this issue, a novel paradigm adopting static motion illusion based on illusion-induced visual evoked potential (IVEP) is proposed for BCIs to enhance visual experience and practicality. APPROACH: This study explored the responses to baseline and illusion tasks including the Rotating-Tilted-Lines (RTL) illusion and Rotating-Snakes (RS) illusion. The distinguishable features were examined between different illusions by analyzing the event-related potentials (ERPs) and amplitude modulation of evoked oscillatory responses. MAIN RESULTS: The illusion stimuli elicited VEPs in an early time window encompassing a negative component (N1) from 110 to 200 ms and a positive component (P2) between 210 and 300 ms. Based on the feature analysis, a filter bank was designed to extract discriminative signals. The task-related component analysis (TRCA) was used to evaluate the binary classification task performance of the proposed method. Then the highest accuracy of 86.67% was achieved with a data length of 0.6 s. SIGNIFICANCE: The results of this study demonstrate that the static motion illusion paradigm has the feasibility of implementation and is promising for VEP-based BCI applications.

19.
Artigo em Inglês | MEDLINE | ID: mdl-37917520

RESUMO

As a significant aspect of cognition, attention has been extensively studied and numerous measurements have been developed based on brain signal processing. Although existing attentional state classification methods have achieved good accuracy by extracting a variety of handcrafted features, spatial features have not been fully explored. This paper proposes an attentional state classification method based on Riemannian manifold to utilize spatial information. Based on the concept of Riemannian manifold of symmetric positive definite (SPD) matrix, the proposed method exploits the structure of covariance matrix to extract spatial features instead of using spatial filters. Specifically, Riemannian distances from intra-class Riemannian means are extracted as features for their robustness. To fully extend the potential of electroencephalograph (EEG) signal, both amplitude and phase information is utilized. In addition, to solve the variance of frequency bands, a filter bank is employed to process the signal of different frequency bands separately. Finally, features are fed into a support vector machine with a polynomial kernel to obtain classification results. The proposed attentional state classification using amplitude and phase feature extraction method based on filter bank and Riemannian manifold (AP-FBRM) method is evaluated on two open datasets including EEG data of 29 and 26 subjects. According to the experimental results, the optimal set of filter bank and the optimal technique to extract features containing both amplitude and phase information are determined. The proposed method respectively achieves accuracies of 88.06% and 80.00% and outperforms 8 baseline methods, which manifests that the proposed method creates an efficient way to recognize attentional state.


Assuntos
Interfaces Cérebro-Computador , Humanos , Algoritmos , Eletroencefalografia/métodos , Processamento de Sinais Assistido por Computador , Encéfalo
20.
Artigo em Inglês | MEDLINE | ID: mdl-38015667

RESUMO

Traditional single-modality brain-computer interface (BCI) systems are limited by their reliance on a single characteristic of brain signals. To address this issue, incorporating multiple features from EEG signals can provide robust information to enhance BCI performance. In this study, we designed and implemented a novel hybrid paradigm that combined illusion-induced visual evoked potential (IVEP) and steady-state visual evoked potential (SSVEP) with the aim of leveraging their features simultaneously to improve system efficiency. The proposed paradigm was validated through two experimental studies, which encompassed feature analysis of IVEP with a static paradigm, and performance evaluation of hybrid paradigm in comparison with the conventional SSVEP paradigm. The characteristic analysis yielded significant differences in response waveforms among different motion illusions. The performance evaluation of the hybrid BCI demonstrates the advantage of integrating illusory stimuli into the SSVEP paradigm. This integration effectively enhanced the spatio-temporal features of EEG signals, resulting in higher classification accuracy and information transfer rate (ITR) within a short time window when compared to traditional SSVEP-BCI in four-command task. Furthermore, the questionnaire results of subjective estimation revealed that proposed hybrid BCI offers less eye fatigue, and potentially higher levels of concentration, physical condition, and mental condition for users. This work first introduced the IVEP signals in hybrid BCI system that could enhance performance efficiently, which is promising to fulfill the requirements for efficiency in practical BCI control systems.


Assuntos
Interfaces Cérebro-Computador , Ilusões , Humanos , Potenciais Evocados Visuais , Eletroencefalografia/métodos , Estimulação Luminosa , Algoritmos
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