1,022 research outputs found

    Ultrahigh-efficiency solution-processed simplified small-molecule organic light-emitting diodes using universal host materials

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    Although solution processing of small-molecule organic light-emitting diodes (OLEDs) has been considered as a promising alternative to standard vacuum deposition requiring high material and processing cost, the devices have suffered from low luminous efficiency and difficulty of multilayer solution processing. Therefore, high efficiency should be achieved in simple-structured small-molecule OLEDs fabricated using a solution process. We report very efficient solution-processed simple-structured small-molecule OLEDs that use novel universal electron-transporting host materials based on tetraphenylsilane with pyridine moieties. These materials have wide band gaps, high triplet energy levels, and good solution processabilities; they provide balanced charge transport in a mixed-host emitting layer. Orange-red (similar to 97.5 cd/A, similar to 35.5% photons per electron), green (similar to 101.5 cd/A, similar to 29.0% photons per electron), and white (similar to 74.2 cd/A, similar to 28.5% photons per electron) phosphorescent OLEDs exhibited the highest recorded electroluminescent efficiencies of solution-processed OLEDs reported to date. We also demonstrate a solution-processed flexible solid-state lighting device as a potential application of our devices.

    Dual quadratic differentials and entire minimal graphs in Heisenberg space

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    We define holomorphic quadratic differentials for spacelike surfaces with constant mean curvature in the Lorentzian homogeneous spaces L(κ,τ)\mathbb{L}(\kappa,\tau) with isometry group of dimension 4, which are dual to the Abresch-Rosenberg differentials in the Riemannian counterparts E(κ,τ)\mathbb{E}(\kappa,\tau), and obtain some consequences. On the one hand, we give a very short proof of the Bernstein problem in Heisenberg space, and provide a geometric description of the family of entire graphs sharing the same differential in terms of a 2-parameter conformal deformation. On the other hand, we prove that entire minimal graphs in Heisenberg space have negative Gauss curvature.Comment: 19 page

    Structural abnormalities in benign childhood epilepsy with centrotemporal spikes (BCECTS)

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    AbstractPurposeThe aim of this study was to investigate cortical thickness and gray matter volume abnormalities in benign childhood epilepsy with centrotemporal spikes (BCECTS). We additionally assessed the effects of comorbid attention-deficit/hyperactivity (ADHD) on these abnormalities.MethodsSurface and volumetric MR imaging data of children with newly diagnosed BCECTS (n=20, 14 males) and age-matched healthy controls (n=20) were analyzed using FreeSurfer (version 5.3.0, https://surfer.nmr.mgh.harvard.edu). An additional comparison was performed between BCECTS children with and without ADHD (each, n=8). A group comparison was carried out using an analysis of covariance with a value of significance set as p<0.01 or p<0.05.ResultsChildren with BCECTS had significantly thicker right superior frontal, superior temporal, middle temporal, and left pars triangularis cortices. Voxel-based morphometric analysis revealed significantly larger cortical gray matter volumes of the right precuneus, left orbitofrontal, pars orbitalis, precentral gyri, and bilateral putamen and the amygdala of children with BCECTS compared to healthy controls. BCECTS patients with ADHD had significantly thicker left caudal anterior and posterior cingulate gyri and a significantly larger left pars opercularis gyral volume compared to BCECTS patients without ADHD.ConclusionChildren with BCECTS have thicker or larger gray matters in the corticostriatal circuitry at the onset of epilepsy. Comorbid ADHD is also associated with structural aberrations. These findings suggest structural disruptions of the brain network are associated with specific developmental electro-clinical syndromes

    Lepidopterous Insect Fauna of Gyeongju National Park in Korea

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    AbstractLepidopterous insect fauna of Gyeongju National Park, was investigated during 25-28 April and 10-11 August 2007, especially in Mt. Namsan Zone. In total, 150 species of 21 families belonging to Lepidoptera were identified through this study. Therefore, a total of 183 species under 25 families are recorded from Gyeongju National Park, including the previous studies

    Effects of a single nucleotide polymorphism in the chicken NK-lysin gene on antimicrobial activity and cytotoxicity of cancer cells

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    NK-lysin is an effector protein of the innate immune system and an important component of host protection. We isolated a SNP in the NK-lysin coding sequence among different chicken breeds. This A to G substitution at the position 271 nucleotide in the ORF results in an Asn (N) to Asp (D) amino acid alteration. We synthesized two 30-aa peptides (N29N and N29D) to compare the biological activity of the helix 2-loop-helix 3 region of NK-lysin resulting from the polymorphic gene. Both peptides were found to be cytotoxic in bacteria and tumor cell cultures at micromolar concentrations. The N29N peptide, however, exhibited greater antibacterial and anticancer activity than the N29D peptide. Circular dichroism spectroscopy of the two peptides in negatively charged single unilamellar vesicles showed spectra typical of α-helical peptides. The helical profile of N29D was reduced substantially compared with that of N29N. However, no structural change was observed in neutral vesicles. ζ-Potential measurements of liposomes incubated with increasing peptide concentrations allowed surface charge neutralization with a negatively charged lipid, but not with a zwitterionic lipid. This result suggests that a difference in electrostatic interaction between lipid membranes and the helical peptides results from the polymorphic gene and is subsequently an important factor in cell lytic activity of variant NK-lysin peptides

    Nanoscale Si coating on the pore walls of SnO2 nanotube anode for Li rechargeable batteries

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    A nanoscale coating of a Si layer on the pore walls of SnO2 nanotubes (Si-coated SnO2) leads to very good electrochemical performance in coulombic efficiency, rate capability and capacity retention compared with untreated SnO2 nanotubes.close514

    Synergistic Effects of Simvastatin and Irinotecan against Colon Cancer Cells with or without Irinotecan Resistance

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    Aims. We here investigated whether the combination of simvastatin and irinotecan could induce the synergistic effect on colon cancer cells with or without resistance to irinotecan. Methods. We investigated cell proliferation assay and assessed cell death detection ELISA and caspase-3 activity assay of various concentrations of simvastatin and irinotecan to evaluate the efficacy of drug combination on colon cancer cells with or without irinotecan resistance. Results. The IC50 values of simvastatin alone and irinotecan alone were 115.4±0.14 μM (r=0.98) and 62.5±0.18 μM (r=0.98) in HT-29 cells without resistance to irinotecan. The IC50 values of these two drugs were 221.9±0.22 μM (r=0.98) and 195.9±0.16 μM (r=0.99), respectively, in HT-29 cell with resistance to irinotecan. The results of combinations of the various concentrations of two drugs showed that combined treatment with irinotecan and simvastatin more efficiently suppressed cell proliferation of HT-29 cells even with resistance to irinotecan as well as without resistance. Furthermore, the combination of simvastatin and irinotecan at 2:1 molar ratio showed the best synergistic interaction. Conclusion. Simvastatin could act synergistically with irinotecan to overcome irinotecan resistance of colon cancer

    Could Fractional Exhaled Nitric Oxide Test be Useful in Predicting Inhaled Corticosteroid Responsiveness in Chronic Cough? A Systematic Review

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    © 2016 Background Fractional exhaled nitric oxide (FENO) is a safe and convenient test for assessing T H 2 airway inflammation, which is potentially useful in the management of patients with chronic cough. Objective To summarize the current evidence on the diagnostic usefulness of FENO for predicting inhaled corticosteroid (ICS) responsiveness in patients with chronic cough. Methods A systematic literature review was conducted to identify articles published in peer-reviewed journals up to February 2015, without language restriction. We included studies that reported the usefulness of FENO (index test) for predicting ICS responsiveness (reference standard) in patients with chronic cough (target condition). The data were extracted to construct a 2 × 2 accuracy table. Study quality was assessed with Quality Assessment of Diagnostic Accuracy Studies 2. Results We identified 5 original studies (2 prospective and 3 retrospective studies). We identified considerable heterogeneities in study design and outcome definitions, and thus were unable to perform a meta-analysis. The proportion of ICS responders ranged from 44% to 59%. Sensitivity and specificity ranged from 53% to 90%, and from 63% to 97%, respectively. The reported area under the curve ranged from abou t 0.60 to 0.87; however, studies with a prospective design and a lower prevalence of asthma had lower area under the curve values. None measured placebo effects or objective cough frequency. Conclusions We did not find strong evidence to support the use of FENO tests for predicting ICS responsiveness in chronic cough. Further studies need to have a randomized, placebo-controlled design, and should use validated measurement tools for cough. Standardization would facilitate the development of clinical evidence

    Taste receptor type 1 member 3 enables western diet-induced anxiety in mice

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    Background Accumulating evidence supports that the Western diet (WD), a diet high in saturated fat and sugary drinks, contributes to the pathogenesis of anxiety disorders, which are the most prevalent mental disorders worldwide. However, the underlying mechanisms by which WD causes anxiety remain unclear. Abundant expression of taste receptor type 1 member 3 (TAS1R3) has been identified in the hypothalamus, a key brain area involved in sensing peripheral nutritional signals and regulating anxiety. Thus, we investigated the influence of excessive WD intake on anxiety and mechanisms by which WD intake affects anxiety development using wild-type (WT) and Tas1r3 deficient (Tas1r3−/−) mice fed a normal diet (ND) or WD for 12 weeks. Results WD increased anxiety in male WT mice, whereas male Tas1r3−/− mice were protected from WD-induced anxiety, as assessed by open field (OF), elevated plus maze (EPM), light–dark box (LDB), and novelty-suppressed feeding (NSF) tests. Analyzing the hypothalamic transcriptome of WD-fed WT and Tas1r3−/− mice, we found 1,432 genes significantly up- or down-regulated as a result of Tas1r3 deficiency. Furthermore, bioinformatic analysis revealed that the CREB/BDNF signaling-mediated maintenance of neuronal regeneration, which can prevent anxiety development, was enhanced in WD-fed Tas1r3−/− mice compared with WD-fed WT mice. Additionally, in vitro studies further confirmed that Tas1r3 knockdown prevents the suppression of Creb1 and of CREB-mediated BDNF expression caused by high levels of glucose, fructose, and palmitic acid in hypothalamic neuronal cells. Conclusions Our results imply that TAS1R3 may play a key role in WD-induced alterations in hypothalamic functions, and that inhibition of TAS1R3 overactivation in the hypothalamus could offer therapeutic targets to alleviate the effects of WD on anxiety.This work was supported by a grant from the Rural Development Administration of Korea (grant number PJ017031). The funding sources had no role in the design of the study, in the collection, analysis, and interpretation of data, or in the writing of the manuscript
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