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1.
Front Hum Neurosci ; 17: 1132254, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37323929

RESUMO

Introduction: EEG signals can non-invasively monitor the brain activities and have been widely used in brain-computer interfaces (BCI). One of the research areas is to recognize emotions objectively through EEG. In fact, the emotion of people changes over time, however, most of the existing affective BCIs process data and recognize emotions offline, and thus cannot be applied to real-time emotion recognition. Methods: In order to solve this problem, we introduce the instance selection strategy into transfer learning and propose a simplified style transfer mapping algorithm. In the proposed method, the informative instances are firstly selected from the source domain data, and then the update strategy of hyperparameters is also simplified for style transfer mapping, making the model training more quickly and accurately for a new subject. Results: To verify the effectiveness of our algorithm, we carry out the experiments on SEED, SEED-IV and the offline dataset collected by ourselves, and achieve the recognition accuracies up to 86.78%, 82.55% and 77.68% in computing time of 7s, 4s and 10s, respectively. Furthermore, we also develop a real-time emotion recognition system which integrates the modules of EEG signal acquisition, data processing, emotion recognition and result visualization. Discussion: Both the results of offline and online experiments show that the proposed algorithm can accurately recognize emotions in a short time, meeting the needs of real-time emotion recognition applications.

2.
PLoS One ; 18(3): e0283573, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36996005

RESUMO

Most of the existing emotion elicitation databases use the film clips as stimuli and do not take into account the age and gender differences of participants. Considering the short videos have the advantages of short in time, easy to understand and strong emotional appeal, we choose them to construct a standardized database of Chinese emotional short videos by the joint analysis of age and gender differences. Two experiments are performed to establish and validate our database. In the Experiment 1, we selected 240 stimuli from 2700 short videos and analyzed the subjective evaluation results of 360 participants with different ages and genders. As a result, a total of 54 short videos with three categories of emotions were picked out for 6 groups of participants, including the male and female respectively aged in 20-24, 25-29 and 30-34. In the Experiment 2, we recorded the EEG signals and subjective experience scores of 81 participants while watching different video stimuli. Both the results of EEG emotion recognition and subjective evaluation indicate that our database of 54 short videos can achieve better emotion elicitation effects compared with film clips. Furthermore, the targeted delivery of specific short videos has also been verified to be effective, helping the researchers choose appropriate emotional elicitation stimuli for different participants and promoting the study of individual differences in emotion responses.


Assuntos
Fatores Etários , População do Leste Asiático , Emoções , Fatores Sexuais , Idoso , Feminino , Humanos , Masculino , Individualidade , Filmes Cinematográficos , Bases de Dados Factuais
3.
Appl Opt ; 61(11): 3008-3018, 2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35471274

RESUMO

The characterization of laser-induced breakdown spectroscopy (LIBS) near the gas-liquid two-phase interface was investigated with the laser acting on the sample along the horizontal direction. Simulation of the laser beam focusing process and observation of laser beam spot images show that difference in focusing positions in the air and the solution results from refraction of the laser beam entering the solution from the air and the change of propagation direction on the container lateral. The peak power and mean irradiance of the focused laser beam spot increase with the distance away from the interface, which is attributed to the fact that the loss of laser energy due to the refraction and reflection of light at the interface decreases with the focusing position moving away from the interface. This variation trend of laser irradiance allows for the growth of the spectral line intensity and lifetime with increasing the distance from the interface. The plasma electron density and temperature decrease with the delay time but increase with the distance away from the interface at the same delay time. Our findings help us to gain more insight into the characteristics and evolution mechanisms of LIBS produced near the gas-liquid two-phase interface, which provides theoretical guidance for the correction of LIBS spectra especially in water pollution monitoring.

4.
Int J Mol Sci ; 22(5)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33669030

RESUMO

Potato tuber dormancy is critical for the post-harvest quality. Snakin/Gibberellic Acid Stimulated in Arabidopsis (GASA) family genes are involved in the plants' defense against pathogens and in growth and development, but the effect of Snakin-2 (SN2) on tuber dormancy and sprouting is largely unknown. In this study, a transgenic approach was applied to manipulate the expression level of SN2 in tubers, and it demonstrated that StSN2 significantly controlled tuber sprouting, and silencing StSN2 resulted in a release of dormancy and overexpressing tubers showed a longer dormant period than that of the control. Further analyses revealed that the decrease expression level accelerated skin cracking and water loss. Metabolite analyses revealed that StSN2 significantly down-regulated the accumulation of lignin precursors in the periderm, and the change of lignin content was documented, a finding which was consistent with the precursors' level. Subsequently, proteomics found that cinnamyl alcohol dehydrogenase (CAD), caffeic acid O-methyltransferase (COMT) and peroxidase (Prx), the key proteins for lignin synthesis, were significantly up-regulated in silencing lines, and gene expression and enzyme activity analyses also supported this effect. Interestingly, we found that StSN2 physically interacts with three peroxidases catalyzing the oxidation and polymerization of lignin. In addition, SN2 altered the hydrogen peroxide (H2O2) content and the activities of superoxide dismutase (SOD) and catalase (CAT). These results suggest that StSN2 negatively regulates lignin biosynthesis and H2O2 accumulation, and ultimately inhibits the sprouting of potato tubers.


Assuntos
Cisteína/metabolismo , Peróxido de Hidrogênio/metabolismo , Lignina/biossíntese , Proteínas de Plantas/metabolismo , Tubérculos/metabolismo , Solanum tuberosum/metabolismo , Oxirredutases do Álcool/metabolismo , Catalase/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Inativação Gênica , Lignina/metabolismo , Peroxidase/metabolismo , Dormência de Plantas/genética , Proteínas de Plantas/genética , Caules de Planta/citologia , Caules de Planta/genética , Caules de Planta/metabolismo , Tubérculos/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Ligação Proteica , Proteína O-Metiltransferase/metabolismo , Proteômica , Plântula/citologia , Plântula/genética , Plântula/metabolismo , Solanum tuberosum/enzimologia , Solanum tuberosum/genética , Superóxido Dismutase-1/metabolismo
5.
MycoKeys ; (29): 49-61, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29559825

RESUMO

An undescribed Curvularia sp. was isolated from the leaf spot disease of Barbados Lily (Hippeastrum striatum (Lam.) Moore). Phylogenetic analyses of combined ITS, 28S, GPD1 and TEF1 sequence data place nine strains of this species in the trifolii-clade, but they clustered together as an independent lineage with strong support. This species was morphologically compared with related species in the trifolii-clade. Based on differences in morphology and phylogeny, it is concluded that this species is a new taxon, introduced as Curvularia microsporasp. nov. Pathogenicity testing determined the new species to be pathogenic on H. striatum.

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