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1.
Neurobiol Learn Mem ; 203: 107795, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37394031

RESUMO

In episodic memory, the old/new effect, the contrast of the waveforms elicited by the correctly recognized studied items and the correctly rejected novel items, has been broadly concerned. However, the contribution of self-referential encoding to the old/new effect in source memory (i.e., source-SRE), is far from clarification; further, it remains unclear whether the contribution is susceptible to the factor of stimulus emotionality. To address these issues, adopting the event-related potential (ERP) technique, this study applied words of three types of emotional valences (positive, neutral, vs. negative) in the self-focus vs. external-focus encoding tasks. In the course of the test, four ERP old/new effects were identified: (a) the familiarity- and recollection-reflected mid-frontal effect (FN400) and late positive component (LPC) were both independent of source-SRE and stimulus emotionality; (b) the reconstruction-driven late posterior negativity (LPN) exhibited an adverse pattern of source-SRE and was susceptible to the emotional valence by encoding focus; and (c) the right frontal old/new effect (RFE), reflecting post-retrieval process, exhibited a source-SRE in emotional words. These effects provide compelling evidence for the influences of both stimulus valence and encoding focus on SRE in source memory, especially during the late processes. Further directions considering more perspectives are put forward.


Assuntos
Potenciais Evocados , Memória Episódica , Reconhecimento Psicológico , Emoções , Eletroencefalografia , Rememoração Mental
2.
Med Sci Monit ; 27: e934297, 2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34355705

RESUMO

Figure 1 is updated due to the mistake that occurred during the layout process. Reference: Aiqing Nie, Yueyue Xiao, Si Liu, Xiaolei Zhu, Delin Zhang. Sensitivity of Reality Monitoring to Fluency: Evidence from Behavioral Performance and Event-Related Potential (ERP) Old/New Effects. Med Sci Monit. 2019; 25: 9490-9498. 10.12659/MSM.917401.

3.
Med Sci Monit ; 25: 9490-9498, 2019 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-31830005

RESUMO

BACKGROUND Item memory and source memory are differently processed with both behavioral and event-related potential (ERP) evidence. Reality monitoring, a specific type of source memory, which refers to the ability to differentiate external sources from internal sources, has been drawing much attention. Among factors that have an impact on reality monitoring, fluency has not been well-studied. Therefore, the current study aimed to investigate whether fluency could affect reality monitoring, through observations on both behavioral performance and electrophysiological patterns. MATERIAL AND METHODS Adopting ERP techniques, participants were required either to watch the presentation of a name/picture pair, or to imagine a picture for each displayed name, once (low fluency) or twice (high fluency). Later they completed a reality monitoring task of identifying names as perceived, imagined, or novel items. Behavioral performance was measured, and ERP waveforms were recorded. RESULTS Behaviorally, high fluency items were faster and more accurately attributed to the sources than low fluency items. ERP waveforms revealed that late positive component (LPC) occurred for all 4 types of items, while imagined items of low fluency did not record a robust FN400 or late frontal old/new effect. CONCLUSIONS As results revealed, the factor of fluency does influence reality monitoring in terms of accuracy and responding speed. Meanwhile, for imagined items of low fluency, the absence of FN400 and frontal old/new effect also suggests the sensitivity of reality monitoring to fluency, because these representatives of familiarity-based processing and post-retrieval monitoring are inevitably involved in the process of differentiating internal source from external source.


Assuntos
Potenciais Evocados/fisiologia , Memória/fisiologia , Teste de Realidade , Adulto , Mapeamento Encefálico , Eletroencefalografia , Feminino , Humanos , Imaginação , Masculino , Estimulação Luminosa , Tempo de Reação , Reconhecimento Psicológico , Adulto Jovem
4.
Phys Med Biol ; 69(5)2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38306973

RESUMO

Objective. To assist urologist and radiologist in the preoperative diagnosis of non-muscle-invasive bladder cancer (NMIBC) and muscle-invasive bladder cancer (MIBC), we proposed a combination models strategy (CMS) utilizing multiparametric magnetic resonance imaging.Approach. The CMS includes three components: image registration, image segmentation, and multisequence feature fusion. To ensure spatial structure consistency of T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and dynamic contrast-enhanced imaging (DCE), a registration network based on patch sampling normalized mutual information was proposed to register DWI and DCE to T2WI. Moreover, to remove redundant information around the bladder, we employed a segmentation network to obtain the bladder and tumor regions from T2WI. Using the coordinate mapping from T2WI, we extracted these regions from DWI and DCE and integrated them into a three-branch dual-channel input. Finally, to fully fuse low-level and high-level features of T2WI, DWI, and DCE, we proposed a distributed multilayer fusion model for preoperative MIBC prediction with five-fold cross-validation.Main results. The study included 436 patients, of which 404 were for the internal cohort and 32 for external cohort. The MIBC was confirmed by pathological examination. In the internal cohort, the area under the curve, accuracy, sensitivity, and specificity achieved by our method were 0.928, 0.869, 0.753, and 0.929, respectively. For the urologist and radiologist, Vesical Imaging-Reporting and Data System score >3 was employed to determine MIBC. The urologist demonstrated an accuracy, sensitivity, and specificity of 0.842, 0.737, and 0.895, respectively, while the radiologist achieved 0.871, 0.803, and 0.906, respectively. In the external cohort, the accuracy of our method was 0.831, which was higher than that of the urologist (0.781) and the radiologist (0.813).Significance. Our proposed method achieved better diagnostic performance than urologist and was comparable to senior radiologist. These results indicate that CMS can effectively assist junior urologists and radiologists in diagnosing preoperative MIBC.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Bexiga Urinária , Humanos , Imageamento por Ressonância Magnética/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/patologia , Estudos Retrospectivos
5.
J Intell ; 11(7)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37504773

RESUMO

Previous studies have confirmed that different degrees of expectation, including the bipolarity of the expected and unexpected, as well as an intermediate level (no expectation), can affect memory. However, only a few investigations have manipulated expectation through experimentally established schema, with no consideration of how expectation impacts both item and source memory. Furthermore, stimulus emotionality may also impact memory. Therefore, we conducted a study to investigate the effects of three levels of expectation on item and source memory while considering the impact of stimulus emotionality. The experiment began with a phase dedicated to learning the rules. In the subsequent study phase, negative and neutral words were manipulated as expected, no expectation, and unexpected, based on these rules. This was followed by tasks focused on item and source memory. The study found that there was a "U-shape" relationship between expectation and item memory. Additionally, the study revealed the distinct impacts of expectation on item and source memory. When it came to item memory, both expected and unexpected words were better remembered than those with no expectations. In source memory, expected words showed memory inferiority for expectation-irrelevant source information, but an advantage for expectation-relevant source information. Stimulus emotionality modulated the effect of expectation on both item and source memory. Our findings provide behavioral evidence for the schema-linked interactions between medial prefrontal and medial temporal regions (SLIMM) theory, which proposes that congruent and incongruent events enhance memory through different brain regions. The different patterns between item and source memory also support dual-process models. Moreover, we speculate that processing events with varying levels of emotionality may undermine the impact of expectation, as implied by other neural investigations.

6.
Artigo em Inglês | MEDLINE | ID: mdl-37402196

RESUMO

In this article, we propose the concept of random polynomial neural networks (RPNNs) realized based on the architecture of polynomial neural networks (PNNs) with random polynomial neurons (RPNs). RPNs exhibit generalized polynomial neurons (PNs) based on random forest (RF) architecture. In the design of RPNs, the target variables are no longer directly used in conventional decision trees, and the polynomial of these target variables is exploited here to determine the average prediction. Unlike the conventional performance index used in the selection of PNs, the correlation coefficient is adopted here to select the RPNs of each layer. When compared with the conventional PNs used in PNNs, the proposed RPNs exhibit the following advantages: first, RPNs are insensitive to outliers; second, RPNs can obtain the importance of each input variable after training; third, RPNs can alleviate the overfitting problem with the use of an RF structure. The overall nonlinearity of a complex system is captured by means of PNNs. Moreover, particle swarm optimization (PSO) is exploited to optimize the parameters when constructing RPNNs. The RPNNs take advantage of both RF and PNNs: it exhibits high accuracy based on ensemble learning used in the RF and is beneficial to describe high-order nonlinear relations between input and output variables stemming from PNNs. Experimental results based on a series of well-known modeling benchmarks illustrate that the proposed RPNNs outperform other state-of-the-art models reported in the literature.

7.
Phys Med Biol ; 68(13)2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37285848

RESUMO

Objective. Computed tomography (CT) and magnetic resonance imaging (MRI) are widely used in medical imaging modalities, and provide valuable information for clinical diagnosis and treatment. However, due to hardware limitations and radiation safety concerns, the acquired images are often limited in resolution. Super-resolution reconstruction (SR) techniques have been developed to enhance the resolution of CT and MRI slices, which can potentially improve diagnostic accuracy. To capture more useful feature information and reconstruct higher quality super-resolution images, we proposed a novel hybrid framework SR model based on generative adversarial networks.Approach. The proposed SR model combines frequency domain and perceptual loss functions, which can work in both frequency domain and image domain (spatial domain). The proposed SR model consists of 4 parts: (i) the discrete Fourier transform (DFT) operation transforms the image from the image domain to frequency domain; (ii) a complex residual U-net performs SR in the frequency domain; (iii) the inverse discrete Fourier transform (iDFT) operation based on data fusion transforms the image from the frequency domain to image domain; (iv) an enhanced residual U-net network is used for SR of image domain.Main results. Experimental results on bladder MRI slices, abdomen CT slices, and brain MRI slices show that the proposed SR model outperforms state-of-the-art SR methods in terms of visual quality and objective quality metric such as the structural similarity (SSIM) and the peak signal-to-noise ratio (PSNR), which proves that the proposed model has better generalization and robustness. (Bladder dataset: upscaling factor of 2: SSIM = 0.913, PSNR = 31.203; upscaling factor of 4: SSIM = 0.821, PSNR = 28.604. Abdomen dataset: upscaling factor of 2: SSIM = 0.929, PSNR = 32.594; upscaling factor of 4: SSIM = 0.834, PSNR = 27.050. Brain dataset: SSIM = 0.861, PSNR = 26.945).Significance. Our proposed SR model is capable of SR for CT and MRI slices. The SR results provide a reliable and effective foundation for clinical diagnosis and treatment.


Assuntos
Encéfalo , Tomografia Computadorizada por Raios X , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Razão Sinal-Ruído , Bexiga Urinária , Processamento de Imagem Assistida por Computador
8.
Life Sci ; 288: 120205, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34871665

RESUMO

AIMS: This study was aimed to explore whether sacran polysaccharide has a therapeutic effect on atopic dermatitis (AD) and its possible mechanisms. MATERIALS AND METHODS: 2, 4-dinitrochlorobenzene (DNCB)-induced AD mice were treated with 0.2% Sacran, 0.5% Sacran and 0.1% tacrolimus. Through scoring dermatitis severity, measuring ear thickness, cracking behavior, open field test, we evaluated the therapeutic effect of Sacran on DNCB-induced AD mice. CD4+ T cells and CD8+ T cells were evaluated by flow cytometry. The relative expression of Ifng and Il4 were measured by real-time quantitative PCR. KEY FINDINGS: Sacran could relieved the symptoms of DNCB-induced AD mice, such as AD score, ear thickness, and IgE release. Sacran may alleviate dermatitis by inhibiting Th2 activation and reducing IgE release. SIGNIFICANCE: Our research further proved that polysaccharide Sacran has anti-dermatitis effects, and also clarified its mechanism of alleviating dermatitis by inhibiting the activation of Th2 cells and reducing the release of IgE, which provides a theoretical basis for the future clinical transformation of polysaccharide Sacran.


Assuntos
Dermatite Atópica/tratamento farmacológico , Dinitroclorobenzeno/toxicidade , Imunoglobulina E/metabolismo , Inflamação/prevenção & controle , Polissacarídeos/farmacologia , Células Th2/imunologia , Animais , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/imunologia , Dermatite Atópica/patologia , Feminino , Indicadores e Reagentes/toxicidade , Inflamação/etiologia , Camundongos , Camundongos Endogâmicos BALB C , Células Th2/efeitos dos fármacos
9.
Percept Mot Skills ; 128(5): 1877-1904, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34218742

RESUMO

A great deal of research has been devoted to examining the neural mechanisms of inductive reasoning. However, the influences of rule validity and time pressure on numerical inductive reasoning remain unclear. In the current study, we aimed to examine the effects of these variables on the time course of rule identification in numerical inductive reasoning. We designed a 3 (task type: valid, invalid, and anomalous) × 2 (time pressure: with time pressure and without time pressure) within-subject experiment based on electroencephalographic event-related potentials (ERP). Behaviorally, we found significant effects of rule validity and time pressure on rule identification. Neurologically, we considered the elicited N200 ERP to reflect conflict detection and found it to be modulated by rule validity but not time pressure. We considered the induced P300 ERP to be primarily related to updating working memory, affected by both rule validity and time pressure. These findings have new implications for better understanding dynamic information processing within numerical inductive reasoning.


Assuntos
Eletroencefalografia , Potenciais Evocados , Cognição , Humanos , Memória de Curto Prazo , Resolução de Problemas
10.
Front Immunol ; 12: 722273, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34526995

RESUMO

Follicular helper T (TFH) cells are specialized CD4+ helper T cells that provide help to B cells in humoral immunity. However, the molecular mechanism underlying generation of TFH cells is incompletely understood. Here, we reported that Damage-specific DNA binding protein 1 (Ddb1) was required for expansion of CD4+ helper T cells including TFH and Th1 cells, germinal center response, and antibody response to acute viral infection. Ddb1 deficiency in activated CD4+ T cells resulted in cell cycle arrest at G2-M phase and increased cell death, due to accumulation of DNA damage and hyperactivation of ATM/ATR-Chk1 signaling. Moreover, mice with deletion of both Cul4a and Cul4b in activated CD4+ T cells phenocopied Ddb1-deficient mice, suggesting that E3 ligase-dependent function of Ddb1 was crucial for genome maintenance and helper T-cell generation. Therefore, our results indicate that Ddb1 is an essential positive regulator in the expansion of CD4+ helper T cells.


Assuntos
Ciclo Celular/genética , Proteínas de Ligação a DNA/genética , Ativação Linfocitária/genética , Ativação Linfocitária/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Animais , Pontos de Checagem do Ciclo Celular , Morte Celular , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Dano ao DNA , Expressão Gênica , Homeostase , Imunofenotipagem , Camundongos , Camundongos Knockout , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Linfócitos T Auxiliares-Indutores/imunologia , Proteína Supressora de Tumor p53/metabolismo
11.
RSC Adv ; 11(29): 17595-17602, 2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35480162

RESUMO

The preparation of Cs y FA1-y PbI x Br3-x -based perovskite by ultrasonic spraying has valuable application in the preparation of tandem solar cells on textured substrates due to its excellent stability and the advantages of large-area uniform preparation from the spraying technology. However, the bandgap of perovskite prepared by spraying method is difficult to adjust, and perovskites with a wide bandgap have the issue of phase instability. Here, we improved the crystallinity of the perovskite by simply controlling the post-annealing temperature. The results show that perovskite film prepared by hybrid spray method has the best crystallinity and device performance at a post-annealing temperature of 170 °C. On this basis, the bandgap of perovskite was changed from 1.53 eV to 1.76 eV by controlling the ratio of the organic halogen precursor solution. When the bandgap is 1.57 eV, a perovskite solar cell with an efficiency of 18.31% is obtained.

12.
Acta Psychol (Amst) ; 210: 103156, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32801072

RESUMO

It has been proved that item memory and source memory are two dissociable processes, as reflected by differential influence at behavioral and electrophysiological levels, the latter being evidenced by the ERP old/new effects. Specially for source memory, the retrieval of color source may be unique from recollecting other types of contextual information, which can be seen from the late posterior negativity (LPN). However, the mediation of emotional valence on the old/new effects for verbal stimuli encoded in colors remains unknown. Adopting words of three emotional valences (i.e., positive, neutral, and negative), with their displayed colors serving as sources, the current experiment aimed to explore the sensitivity of old/new effects to emotion for both item memory and source memory. Results demonstrated that: the FN400 that reflects familiarity was recorded and it was sensitive to emotional valence across both memory tasks; the mediation of emotional valence was absent in recollection-reflected LPC, neither for item memory nor for source memory; an association between LPN and color source retrieval was confirmed, with reliable amplitudes for neutral words but not for emotional words. These data were discussed in terms of the dual-process model and other accounts. Future research directions were recommended.


Assuntos
Cor , Eletroencefalografia , Emoções , Potenciais Evocados , Humanos , Reconhecimento Psicológico
13.
ACS Appl Mater Interfaces ; 11(47): 44101-44108, 2019 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-31680509

RESUMO

Perovskite solar cells (PSCs) have gained tremendous research interest because of their tolerance of defects, low cost, and facile processing. In PSC devices, PbI2 has been utilized to passivate defects at perovskite film surfaces and GBs; however, a systematic mechanism of PbI2 in situ passivation for enhancing the solar cells efficiency has not been fully explored. Here, this work, we systematically studies the effect of the precise PbI2 ratio and the PbI2 in situ passivation mechanism based on trap density, carrier lifetime, Fermi level, and so forth. This study finds the appropriate ratio of I/Pb to be around 2.57:1 using energy-dispersive spectroscopy. After the moderate excess PbI2 in situ passivation, the trap density is reduced from 6.12 × 1016 to 3.38 × 1016 cm-3, and the carrier lifetime is extended from 168.35 to 368.77 ps by using fs-TA spectroscopy. This result indicates that the moderate excess PbI2 in situ passivation can reduce the trap density and suppress the nonradiative recombination. The efficiency of solar cell has shown a nearly 11.3% improvement of 19.55% for an I/Pb ratio of 2.57:1 compared with 2.69:1. It also demonstrates that the efficiency of PSCs can be enhanced effectively by PbI2 in situ passivation.

14.
Eur J Med Chem ; 158: 201-213, 2018 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-30216852

RESUMO

A series of 6,7-disubstituted-4-phenoxyquinoline derivatives bearing the 1,8-naphthyridin-2-one moiety were designed, synthesized and evaluated for their biological activities. The target compounds exhibited moderate to high antiproliferative activity against three cancer cell lines (A549, HepG2 and MCF-7) and several compounds (25, 27, 33, 37, 41, 43, 49 and 53) were evaluated for the activity against c-Met kinase. The most promising compound 33 (IC50 c-Met = 2.36 nM) showed excellent activity against A549, HepG2 and MCF-7 cell lines with IC50 values of 0.23 µM, 0.42 µM and 0.21 µM, respectively, which was 1.5-2.1 times of the positive control. Furthermore, compound 33 was evaluated for the activity against Flt3, PDGFR-α, PDGFR-ß, c-Kit, Flt4, ALK and EGFR kinase. Structure activity relationship studies indicated that mono-EWGs (such as R2 = F) at 4-position of moiety C was a key factor in improving the antitumor activity. In addition, further research on compound 33 was mainly including concentration dependence, apoptosis (acridine orange staining), apoptosis result analyzing and molecular docking.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Naftiridinas/química , Naftiridinas/farmacologia , Quinolinas/química , Quinolinas/farmacologia , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Acoplamento Molecular , Naftiridinas/síntese química , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Quinolinas/síntese química , Relação Estrutura-Atividade
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