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1.
Sensors (Basel) ; 23(13)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37447736

RESUMO

This paper presents a cognitive psychology experiment to explore the differences between 2D and virtual reality (VR) film editing techniques. We recruited sixteen volunteers to view a range of different display modes and edit types of experimental material. An electroencephalogram (EEG) was recorded simultaneously while the participants watched. Subjective results showed that the VR mode reflects higher load scores, particularly in the effort dimension. Different editing types have no effect on subjective immersion scores. The VR mode elicited stronger EEG energy, with differences concentrated in the occipital, parietal, and central regions. On the basis of this, visual evoked potential (VEP) analyses were conducted, and the results indicated that VR mode triggered greater spatial attention, while editing in 2D mode induced stronger semantic updating and active understanding. Furthermore, we found that while the effect of different edit types in both display modes is similar, cross-axis editing triggered greater cognitive violations than continuity editing, which could serve as scientific theoretical support for the development of future VR film editing techniques.


Assuntos
Potenciais Evocados Visuais , Realidade Virtual , Humanos , Eletroencefalografia , Atenção/fisiologia , Filmes Cinematográficos
2.
Sensors (Basel) ; 22(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36366201

RESUMO

Previous research comparing traditional two-dimensional (2D) and virtual reality with stereoscopic vision (VR-3D) stimulations revealed that VR-3D resulted in higher levels of immersion. However, the effects of these two visual modes on emotional stimulus processing have not been thoroughly investigated, and the underlying neural processing mechanisms remain unclear. Thus, this paper introduced a cognitive psychological experiment that was conducted to investigate how these two visual modes influence emotional processing. To reduce fatigue, participants (n = 16) were randomly assigned to watch a series of 2D and VR-3D short emotional videos for two days. During their participation, electroencephalograms (EEG) were recorded simultaneously. The results showed that even in the absence of sound, visual stimuli in the VR environment significantly increased emotional arousal, especially in the frontal region, parietal region, temporal region, and occipital region. On this basis, visual evoked potential (VEP) analysis was performed. VR stimulation compared to 2D led to a larger P1 component amplitude, while VEP analysis based on the time course of the late event-related potential component revealed that, after 1200 ms, the differences across visual modes became stable and significant. Furthermore, the results also confirmed that VEP in the early stages is more sensitive to emotions and presumably there are corresponding emotion regulation mechanisms in the late stages.


Assuntos
Potenciais Evocados Visuais , Realidade Virtual , Humanos , Emoções/fisiologia , Potenciais Evocados/fisiologia , Eletroencefalografia/métodos , Nível de Alerta
3.
Sensors (Basel) ; 21(21)2021 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-34770482

RESUMO

This paper introduces a cognitive psychological experiment that was conducted to analyze how traditional film editing methods and the application of cognitive event segmentation theory perform in virtual reality (VR). Thirty volunteers were recruited and asked to watch a series of short VR videos designed in three dimensions: time, action (characters), and space. Electroencephalograms (EEG) were recorded simultaneously during their participation. Subjective results show that any of the editing methods used would lead to an increased load and reduced immersion. Furthermore, the cognition of event segmentation theory also plays an instructive role in VR editing, with differences mainly focusing on frontal, parietal, and central regions. On this basis, visual evoked potential (VEP) analysis was performed, and the standardized low-resolution brain electromagnetic tomography algorithm (sLORETA) traceability method was used to analyze the data. The results of the VEP analysis suggest that shearing usually elicits a late event-related potential component, while the sources of VEP are mainly the frontal and parietal lobes. The insights derived from this work can be used as guidance for VR content creation, allowing VR image editing to reveal greater richness and unique beauty.


Assuntos
Realidade Virtual , Cognição , Eletroencefalografia , Potenciais Evocados , Potenciais Evocados Visuais , Humanos
4.
J Ethnopharmacol ; 254: 112670, 2020 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-32135242

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Anoectochilus roxburghii (A. roxburghii) is a popular folk medicine in many Asian countries, which has been used traditionally for treatment of some diseases such as diabetes, tumors, hyperlipemia, and hepatitis. The ethanol extract from A. roxburghii was recently shown to exert better ability to scavenge free radicals in vitro and possess antioxidant on natural aging mice in vivo. AIM OF THE STUDY: This study is to characterize the chemical composition, and investigate the protective effect of the A. roxburghii flavonoids extract (ARF) against hydrogen peroxide (H2O2)-induced oxidative stress in LO2 cells in vitro and D-galactose (D-gal)-induced aging mice model in vivo, and explore the underlying mechanisms. MATERIALS AND METHODS: The chemical components of the flavonoids extract fromA. roxburghii were detected by ultraperformance lipid chromatography coupled with quadrupole-time-of-flight mass spectrometry (UPLC-QTOF-MS/MS). H2O2 was used to establish an oxidative stress model in LO2 cells. Cytotoxic and protective effects of ARF on the LO2 cells were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Moreover, the levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and malondialdehyde (MDA) in cell supernatants were measured by commercial reagent kits. Kun-Ming mice were induced to aging with D-gal (400 mg/kg, BW) by subcutaneous injection for 58 days. From the 28th day to the 58th day of D-gal treatment, ARF (122.5, 245 and 490 mg/kg, BW) and vitamin E (100 mg/kg, BW) were orally administrated to aging mice once a day for consecutive 30 days. After 25 days of the treatment with ARF, learning and memory were assessed using Morris Water Maze (MWM). At the end of the test period, the animals were euthanized by cervical dislocation, and the levels of SOD, GSH-PX, and MDA in serum, liver homogenates and brain homogenates were measured. The levels of monoamine oxidase (MAO) and acetylcholinesterase (AchE) were determined in brain homogenates. Skin and liver histopathological morphology were observed by H&E staining. Furthermore, antioxidant-related gene expression levels in the liver were carried out by quantitative real-time polymerase chain reaction (qRT-PCR). RESULTS: Nine flavonoids were identified in the extracts of A. roxburghii. In vitro assay, a high concentration of ARF (>612.5 µg/ml) reduced the survival rate and had toxic effects on LO2 cells. In addition, ARF (245 µg/ml, 490 µg/ml) and Vitamin C (200 µg/ml) markedly inhibited generations of MDA and increased activities of SOD, GSH-PX in H2O2-induced LO2 cells supernatants. In vivo assay, ARF (122.5 mg/kg, 245 mg/kg and 490 mg/kg) and Vitamin E (100 mg/kg) not only ameliorated learning and memory ability but also improved skin and liver pathological alterations. Strikingly, ARF significantly decreased MDA and MAO levels, markedly enhanced antioxidant enzyme (SOD and GSH-PX) activities. Further, compared to the D-gal group, ARF could obviously up-regulate glutathione peroxidase-1 (GPx-1) and glutathione peroxidase-4 (GPx-4) mRNA levels. CONCLUSIONS: These findings suggested that ARF protects LO2 cells against H2O2-induced oxidative stress and exerts the potent anti-aging effects in D-gal aging mice model, which may be related to the inhibition of oxidative stress. Flavonoid compounds may contribute to the anti-oxidative capability and modulating aging.


Assuntos
Envelhecimento/efeitos dos fármacos , Antioxidantes/farmacologia , Flavonoides/farmacologia , Orchidaceae/química , Estresse Oxidativo/efeitos dos fármacos , Compostos Fitoquímicos/farmacologia , Acetilcolinesterase/metabolismo , Animais , Encéfalo/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Flavonoides/isolamento & purificação , Galactose , Expressão Gênica , Glutationa Peroxidase/sangue , Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio , Fígado/metabolismo , Masculino , Malondialdeído/sangue , Malondialdeído/metabolismo , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Monoaminoxidase/metabolismo , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo
5.
J Ethnopharmacol ; 241: 111956, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31129309

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Dryopteris fragrans (L.) Schott (D. fragrans), a deciduous perennial herb, has been traditionally used for treatment of various skin diseases in Heilongjiang province of China for many years. Phloroglucinol derivatives extracted from D. fragrans were the most effective fraction against dermatophytes. Isoflavaspidic acid PB is a typically phloroglucinol derivative which extracted from D. fragrans and has been reported to exert anti-fungal activities against several dermatophytes. AIM OF THE STUDY: This study aimed to evaluate anti-fungal and anti-biofilm activity of isoflavaspidic acid PB on planktonic and biofilm growth of dermatophytes and explore possible mechanisms of anti-biofilm. MATERIALS AND METHODS: Minimal inhibitory concentrations (MIC) and minimal fungicidal concentrations (MFC) of isoflavaspidic acid PB against 25 isolates of dermatophytes were determined by the Clinical and Laboratory Standards Institute (CLSI) M38-A2 method. The effects of isoflavaspidic acid PB on dermatophytes biofilm formation and pre-formed biofilm were assessed by 2.3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[carbonyl (phenylamino)]-2H-tetrazolium hydroxide (XTT) assay. Morphology of mature biofilm were observed by Scanning Electron Microscope (SEM). Biomass, exopolysaccharide and ergosterol content of mature biofilm were analyzed by gravimetric analysis, anthranone sulfuric acid method and Ultra Performance Liquid Chromatography (UPLC) assay respectively. RESULT: The MIC and MFC ranges of isoflavaspidic acid PB against 25 isolates of dermatophytes were 20-80 µg/mL and 40-80 µg/mL respectively. Isoflavaspidic acid PB (2 MIC) inhibited not only Trichophyton biofilm formation (54.8% ∼ 81.2%) but also the metabolic activity of mature biofilm (20.7% ∼ 44.2%). The result of SEM showed that isoflavaspidic acid PB (8 MIC) could destroy the morphology of hyphae seriously. Comparing with control group, biomass, exopolysaccharide and ergosterol content of the mature biofilm under isoflavaspidic acid PB (8 MIC) were significantly decreased (P < 0.01). CONCLUSION: Isoflavaspidic acid PB had anti-fungal and fungicidal activities against dermatophytes. Isoflavaspidic acid PB could inhibit the biofilm of Trichophyton. The mechanism might be related to the decline of the biofilm biomass, exopolysaccharide and ergosterol content. These results showed that isoflavaspidic acid PB could be explored for promising anti-biofilm drugs.


Assuntos
Antifúngicos/farmacologia , Dryopteris , Floroglucinol/análogos & derivados , Floroglucinol/farmacologia , Trichophyton/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Ergosterol/metabolismo , Testes de Sensibilidade Microbiana , Trichophyton/fisiologia
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