分类: 生物学 >> 生物物理学 提交时间: 2016-05-15
摘要: Background Cilostazol, an anti-platelet drug for treating coronary heart disease, has been reported to modulate immune cell functions. Plasmacytoid dendritic cells (pDCs) have been found to participate in the progression of atherosclerosis mainly through interferon a (IFN-alpha) production. Whether cilostazol influences pDCs activation is still not clear. In this study, we aimed to investigate the effects of cilostazol on cell activation and antigen presentation of pDCs in vitro in this study. Methods Peripheral blood mononuclear cells isolated by Ficoll centrifugation and pDCs sorted by flow cytometry were used in this study. After pretreated with cilostazol for 2 h, cells were stimulated with CpG-A, R848 or virus for 6 h or 20 h, or stimulated with CpG-B for 48 h and then co-cultured with naive T cell for five days. Cytokines in supernatant and intracellular cytokines were analyzed by ELISA or flow cytometry respectively. Results Our data indicated that cilostazol could inhibit IFN-alpha and tumor necrosis factor a (TNF-alpha) production from pDCs in a dose-dependent manner. In addition, the ability of priming naive T cells of pDCs was also impaired by cilostazol. The inhibitory effect was not due to cell killing since the viability of pDCs did not change upon cilostazol treatment. Conclusion Cilostazol inhibits pDCs cell activation and antigen presentation in vitro, which may explain how cilostazol protects against atherosclerosis.
分类: 心理学 >> 发展心理学 提交时间: 2023-08-17
摘要: Relative deprivation is one of the factors that influences the development of personality and behavior. However, it is still unclear whether and how relative deprivation decreases the prosocial behavior of adolescents. This study aimed to examine the association between relative deprivation and adolescent prosocial behavior and the role of emotion regulation strategies and empathy in modifying this association. The present study included 609 secondary school students (M = 15.42 years, SD = 0.653) in Fujian Province, China. All participants completed the Relative Deprivation Questionnaire, Emotion Regulation Scale, the Basic Empathy Scale, and Prosocial Behavior Scale. The collected data were analyzed using SPSS 25.0 and Mplus 7.4. Relative deprivation was negatively correlated with cognitive reappraisal, but positively correlated with expressive suppression. Cognitive reappraisal was positively correlated with empathy and prosocial behavior, but expressive suppression was not. Empathy was positively correlated with prosocial behavior. Relative deprivation decreased prosocial behavior through (a) cognitive reappraisal, (b) empathy, and (c) chain mediation of cognitive reappraisal and empathy. No significant mediating effect of expressive suppression was found. The results indicate that relative deprivation decreases adolescent prosocial behavior, and that cognitive reappraisal and empathy are the potential psychological mechanisms that affect the association between relative deprivation and adolescent prosocial behavior.
分类: 物理学 >> 核物理学 提交时间: 2024-03-08
摘要: Neutron radiography is a crucial nondestructive testing technology widely used in the aerospace, military, andnuclear industries. However, because of the physical limitations of neutron sources and collimators, the resultingneutron radiographic images inevitably exhibit multiple distortions, including noise, geometric unsharpness,and white spots. Furthermore, these distortions are particularly significant in compact neutron radiography systemswith low neutron fluxes. Therefore, in this study, we devised a multi-distortion suppression network thatemploys a modified generative adversarial network to improve the quality of degraded neutron radiographic images.Real neutron radiographic image datasets with various types and levels of distortion were built for the firsttime as multi-distortion suppression datasets. Thereafter, the coordinate attention mechanism was incorporatedinto the backbone network to augment the capability of the proposed network to learn the abstract relationshipbetween ideally clear and degraded images. Extensive experiments were performed; the results show that theproposed method can effectively suppress multiple distortions in real neutron radiographic images and achievestate-of-the-art perceptual visual quality, thus demonstrating its application potential in neutron radiography.
分类: 天文学 >> 天文仪器与技术 提交时间: 2024-01-22 合作期刊: 《天文技术与仪器(英文)》
摘要:An extreme ultraviolet solar corona multispectral imager can allow direct observation of high temperature coronal plasma, which is related to solar flares, coronal mass ejections and other significant coronal activities. This manuscript proposes a novel end-to-end computational design method for an extreme ultraviolet (EUV) solar corona multispectral imager operating at wavelengths near 100 nm, including a stray light suppression design and computational image recovery. To suppress the strong stray light from the solar disk, an outer opto-mechanical structure is designed to protect the imaging component of the system. Considering the low reflectivity (less than 70%) and strong-scattering (roughness) of existing extreme ultraviolet optical elements, the imaging component comprises only a primary mirror and a curved grating. A Lyot aperture is used to further suppress any residual stray light. Finally, a deep learning computational imaging method is used to correct the individual multi-wavelength images from the original recorded multi-slit data. In results and data, this can achieve a far-field angular resolution below 7", and spectral resolution below 0.05 nm. The field of view is ±3 R☉ along the multi-slit moving direction, where R☉ represents the radius of the solar disk. The ratio of the corona's stray light intensity to the solar center's irradiation intensity is less than 10−6 at the circle of 1.3 R☉.
分类: 生物学 >> 生物物理学 >> 神经科学 提交时间: 2016-05-11
摘要: All neurodegenerative diseases are associated with oxidative stress-induced neuronal death. Forkhead box O3a (FOXO3a) is a key transcription factor involved in neuronal apoptosis. However, how FOXO3a forms complexes and functions in oxidative stress processing remains largely unknown. In the present study, we show that histone deacetylase 2 (HDAC2) forms a physical complex with FOXO3a, which plays an important role in FOXO3a-dependent gene transcription and oxidative stress-induced mouse cerebellar granule neuron (CGN) apoptosis. Interestingly, we also found that HDAC2 became selectively enriched in the promoter region of the p21 gene, but not those of other target genes, and inhibited FOXO3a-mediated p21 transcription. Furthermore, we found that oxidative stress reduced the interaction between FOXO3a and HDAC2, leading to an increased histone H4K16 acetylation level in the p21 promoter region and upregulated p21 expression in a manner independent of p53 or E2F1. Phosphorylation of HDAC2 at Ser 394 is important for the HDAC2-FOXO3a interaction, and we found that cerebral ischemia/reperfusion reduced phosphorylation of HDAC2 at Ser 394 and mitigated the HDAC2-FOXO3a interaction in mouse brain tissue. Our study reveals the novel regulation of FOXO3a-mediated selective gene transcription via epigenetic modification in the process of oxidative stress-induced cell death, which could be exploited therapeutically.
分类: 生物学 >> 生物物理学 提交时间: 2016-05-11
摘要: Hepatocellular carcinoma (HCC) is the most prevalent subtype of liver cancer, and it is characterized by a high rate of recurrence and heterogeneity. Liver cancer stem cells (CSCs) may well contribute to both of these pathological properties, but the mechanisms underlying their self-renewal and maintenance are poorly understood. Here, using transcriptome microarray analysis, we identified a long noncoding RNA (IncRNA) termed IncTCF7 that is highly expressed in HCC tumors and liver CSCs. LncTCF7 is required for liver CSC self-renewal and tumor propagation. Mechanistically, IncTCF7 recruits the SWI/SNF complex to the promoter of TCF7 to regulate its expression, leading to activation of Wnt signaling. Our data suggest that IncTCF7-mediated Wnt signaling primes liver CSC self-renewal and tumor propagation. In sum, therefore, we have identified an IncRNA-based Wnt signaling regulatory circuit that promotes tumorigenic activity in liver cancer stem cells, highlighting the role that IncRNAs can play in tumor growth and propagation.
分类: 物理学 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要: The excess of top quark forward-backward asymmetry (AtFBAFBtA^t_{FB}) reported by the Tevatron and the enhancement of the Higgs decay to diphoton observed by the LHC may point to a same origin of new physics. In this note we examined such anomalies in the
分类: 生物学 >> 生物物理学 >> 神经科学 提交时间: 2016-05-12
摘要: The brain constantly creates perceptual predictions about forthcoming stimuli to guide perception efficiently. Abundant studies have demonstrated that perceptual predictions modulate sensory activities depending on whether the actual inputs are consistent with one particular prediction. In real-life contexts, however, multiple and even conflicting predictions might concurrently exist to be tested, requiring a multiprediction coordination process. It remains largely unknown how multiple hypotheses are conveyed and harmonized to guide moment-by-moment perception. Based on recent findings revealing that multiple locations are sampled alternatively in various phase of attentional rhythms, we hypothesize that this oscillation-based temporal organization mechanism may also underlie the multiprediction coordination process. To address the issue, we used well established priming paradigms in combination with a time-resolved behavioral approach to investigate the fine temporal dynamics of the multiprediction harmonization course in human subjects. We first replicate classical priming effects in slowly developing trends of priming time courses. Second, after removing the typical priming patterns, we reveal a new theta-band (similar to 4 Hz) oscillatory component in the priming behavioral data regardless of whether the prime was masked. Third, we show that these theta-band priming oscillations triggered by congruent and incongruent primes are in an out-of-phase relationship. These findings suggest that perceptual predictions return to low-sensory areas not continuously but recurrently in a theta-band rhythm (every 200-300 ms) and that multiple predictions are dynamically coordinated in time by being conveyed in different phases of the theta-band oscillations to achieve dissociated but temporally organized neural representations.
分类: 物理学 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要: In the framework of the simplest little Higgs model (SLHM), we study the production of a pair of neutral CP-even Higgs bosons at the LHC. First, we examine the production rate and find that it can be significantly larger than the SM prediction. Then we in
分类: 物理学 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要: We study the process \gamma\gamma -> h -> b b_bar at ILC as a probe of different little Higgs models, including the simplest little Higgs model (SLH), the littlest Higgs model (LH), and two types of littlest Higgs models with T-parity (LHT-I, LHT-II). Com
分类: 物理学 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要: As the most important discovery channel for a light Higgs boson at the LHC, the di-photon signal gg→h→γγ is sensitive to underlying physics. In this work we investigate such a signal in a comparative way by considering three different supersymmetric model
分类: 物理学 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要: Measuring the Higgs self-coupling is one of the crucial physics goals at the LHC Run-2 and other future colliders. In this work, we attempt to figure out the size of SUSY effects on the trilinear self-coupling of the 125 GeV Higgs boson in the MSSM and NM
分类: 物理学 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要: In the framework of the simplest little Higgs model (SLHM), we study the production of a pair of neutral CP-even Higgs bosons at the LHC. First, we examine the production rate and find that it can be significantly larger than the SM prediction. Then we in
分类: 物理学 分类: 物理学 >> 基本粒子与场物理学 提交时间: 2016-12-28
摘要: Little Higgs theory naturally predicts a light Higgs boson whose most important discovery channel at the LHC is the di-photon signal pp→h→γγpp→h→γγpp\to h\to \gamma\gamma. In this work we perform a comparative study for this signal in some typical little