Effect of electrolytes on electrochemical properties of graphene sheet covered with polypyrrole thin layer

AbstractGraphene sheet (GS) was successfully covered with a polypyrrole (PPy) thin layer through in situ chemical oxidative polymerization of pyrrole monomers in aqueous solution by using GS as a support material and ferric trichloride as an oxidant. The resulting nanocomposite was studied by field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR) and electrical measurements, including cyclic voltammetry (CV), galvanostatic charge/discharge experiment (GCD), and impedance spectroscopy (EIS). It has been found that the nanocomposite exhibited a typically curved and layer–like structure, and conformational change of PPy chains occurred due to the π–π stacking interaction between the graphitic structures in GS and aromatic rings of the PPy chains. More attention was paid to the effect of electrolytes on electrochemical properties of the nanocomposites, as expected, electrochemical performance was dependent on the nature of the electrolyte, and the neutral electrolytes containing alkali metal ions were found to be very suitable for GS/PPy nanocomposite. Compared with the pure PPy, the nanocomposite possessed larger specific capacitance and lower internal impedance, indicating that the nanocomposite can be a promising candidate as electrode material for supercapacitors

The Development and Validation of an EFL Learner Attitude Scale for Phonetic Symbol Learning in A Chinese University Context

Research has established that learner attitude significantly impacts the outcomes of learning English as a foreign language (EFL). However, previous studies have rarely considered a validated attitude scale for English phonetic symbol learning (EPSL). This study aims to develop and validate a scale to measure students\u27 attitudes toward EPSL by integrating findings from learning attitude research in education and psychology. The results demonstrate that the attitude scale can predict attitudes towards EPSL in the context of a Chinese university and has good reliability and validity (KMO=0.892, α=0.749). Pedagogical suggestions are made to help students develop a more positive attitude toward EPSL

N-(2-{[7-(2-Anilinoeth­oxy)-3,6-dibromo­naphthalen-2-yl]­oxy}eth­yl)aniline

In the title compound, C26H24Br2N2O2, the central naphthalene system carries two Br atoms and two –CH2CH2NHC6H5 substituents. The phenyl rings of the latter residues are inclined at 74.17 (17) and 51.4 (2)° with respect to the naphthalene ring system. Each alkyl chain adopts a fully extended all-cis conformation with respect to the naphthalene and phenyl rings [N—C—C—O torsion angles = 68.6 (4) and 60.5 (4)°]. In the crystal, one of the N—H groups forms bifurcated N—H⋯(Br,O) hydrogen bonds, which link the mol­ecules into inversion-related dimers. The centrosymmetric dimers are aggregated via pairs of C—H⋯π inter­actions into sheets parallel to (110)

Efficient sonochemical catalytic degradation of tetracycline using TiO2 fractured nanoshells

Overexposure to antibiotics originating in wastewater has profound environmental and health implications. Conventional treatment methods are not fully effective in removing certain antibiotics, such as the commonly used antibiotic, tetracycline, leading to its accumulation in water catchments. Alternative antibiotic removal strategies are garnering attention, including sonocatalytic oxidative processes. In this work, we investigated the degradation of tetracycline using a combination of TiO2 fractured nanoshells (TFNs) and an advanced sonochemical reactor design. The study encompassed an examination of multiple process parameters to understand their effects on the degradation of tetracycline. These included tetracycline adsorption on TFNs, reaction time, initial tetracycline concentration, solvent pH, acoustic pressure amplitude, number of acoustic cycles, catalyst dosage, TFNs' reusability, and the impact of adjuvants such as light and H2O2. Though TFNs adsorbed tetracycline, the addition of ultrasound was able to degrade tetracycline completely (with 100% degradation) within six minutes. Under the optimal operating conditions, the proposed sonocatalytic system consumed 80% less energy compared to the values reported in recently published sonocatalytic research. It also had the lowest CO2 footprint when compared to the other sono-/photo-based technologies. This study suggests that optimizing the reaction system and operating the reaction under low power and at a lower duty cycle are effective in achieving efficient cavitation for sonocatalytic reactions

Modelling of the Automatic Depth Control Electrohydraulic System Using RBF Neural Network and Genetic Algorithm

The automatic depth control electrohydraulic system of a certain minesweeping tank is complex nonlinear system, and it is difficult for the linear model obtained by first principle method to represent the intrinsic nonlinear characteristics of such complex system. This paper proposes an approach to construct accurate model of the electrohydraulic system with RBF neural network trained by genetic algorithm-based technique. In order to improve accuracy of the designed model, a genetic algorithm is used to optimize centers of RBF neural network. The maximum distance measure is adopted to determine widths of radial basis functions, and the least square method is utilized to calculate weights of RBF neural network; thus, computational burden of the proposed technique is relieved. The proposed technique is applied to the modelling of the electrohydraulic system, and the results clearly indicate that the obtained RBF neural network can emulate the complex dynamic characteristics of the electrohydraulic system satisfactorily. The comparison results also show that the proposed algorithm performs better than the traditional clustering-based method

In silico discovery of human natural antisense transcripts

BACKGROUND: Several high-throughput searches for ppotential natural antisense transcripts (NATs) have been performed recently, but most of the reports were focused on cis type. A thorough in silico analysis of human transcripts will help expand our knowledge of NATs. RESULTS: We have identified 568 NATs from human RefSeq RNA sequences. Among them, 403 NATs are reported for the first time, and at least 157 novel NATs are trans type. According to the pairing region of a sense and antisense RNA pair, hNATs are divided into 6 classes, of which about 87% involve 5' or 3' UTR sequences, supporting the regulatory role of UTRs. Among a total of 535 NAT pairs related with splice variants, 77.4% (414/535) have their pairing regions affected or completely eliminated by alternative splicing, suggesting significant relationship of alternative splicing and antisense-directed regulation. The extensive occurrence of splice variants in hNATs and other multiple pairing patterns results in a one-to-many relationship, allowing the formation of complex regulation networks. Based on microarray data from Stanford Microarray Database, two hNAT pairs were found to display significant inverse expression patterns before and after insulin injection. CONCLUSION: NATs might carry out more extensive and complex functions than previously thought. Combined with endogenous micro RNAs, hNATs could be regarded as a special group of transcripts contributing to the complex regulation networks

Preventive effect of Ibrolipim on suppressing lipid accumulation and increasing lipoprotein lipase in the kidneys of diet-induced diabetic minipigs

<p>Abstract</p> <p>Background</p> <p>The role of renal lipoprotein lipase (LPL) <it>per se </it>in kidney diseases is still controversial and obscure. The purpose of this study was to observe the preventive effects of Ibrolipim, a LPL activator, on lipid accumulation and LPL expression in the kidneys of minipigs fed a high-sucrose and high-fat diet (HSFD).</p> <p>Methods</p> <p>Male Chinese Bama minipigs were fed a control diet or HSFD with or without 0.1 g/kg/day Ibrolipim for 5 months. Body weight, plasma glucose, insulin, lipids, LPL activity, and urinary microalbumin were measured. Renal tissue was obtained for detecting LPL activity and contents of triglyceride and cholesterol, observing the renal lipid accumulation by Oil Red O staining, and examining the mRNA and protein expression of LPL by real time PCR, Western Blot and immunohistochemistry.</p> <p>Results</p> <p>Feeding HSFD to minipigs caused weight gain, hyperglycemia, hyperinsulinemia, hyperlipidemia and microalbuminuria. HSFD increased plasma LPL activity while it decreased the mRNA and protein expression and activity of LPL in the kidney. The increases in renal triglyceride and cholesterol contents were associated with the decrease in renal LPL activity of HSFD-fed minipigs. In contrast, supplementing Ibrolipim into HSFD lowered body weight, plasma glucose, insulin, triglyceride and urinary albumin concentrations while it increased plasma total cholesterol and HDL-C. Ibrolipim suppressed the renal accumulation of triglyceride and cholesterol, and stimulated the diet-induced down-regulation of LPL expression and activity in the kidney.</p> <p>Conclusions</p> <p>Ibrolipim exerts renoprotective and hypolipidemic effects <it>via </it>the increase in renal LPL activity and expression, and thus the increased expression and activity of renal LPL play a vital role in suppressing renal lipid accumulation and ameliorating proteinuria in diet-induced diabetic minipigs.</p

Long working range light field microscope with fast scanning multifocal liquid crystal microlens array

The light field microscope has the potential of recording the 3D information of biological specimens in real time with a conventional light source. To further extend the depth of field to broaden its applications, in this paper, we proposed a multifocal high-resistance liquid crystal microlens array instead of the fixed microlens array. The developed multifocal liquid crystal microlens array can provide high quality point spread function in multiple focal lengths. By adjusting the focal length of the liquid crystal microlens array sequentially, the total working range of the light field microscope can be much extended. Furthermore, in our proposed system, the intermediate image was placed in the virtual image space of the microlens array, where the condition of the lenslets numerical aperture was considerably smaller. Consequently, a thin-cell-gap liquid crystal microlens array with fast response time can be implemented for time-multiplexed scanning

A Non‐Pt Electronically Coupled Semiconductor Heterojunction for Enhanced Oxygen Reduction Electrocatalytic Property

Hybrid faceted‐Ag3PO4/cube‐Cu2O composite materials have been fabricated and employed as oxygen reduction electrocatalysts for proton exchange membrane fuel cells (PEMFCs). The charge separation effect via the formation of PN junction has been demonstrated to boost the electrocatalysis toward oxygen reduction reaction. The as‐prepared rhombic dodecahedron‐Ag3PO4/cube‐Cu2O/C hybrid catalyst shows a mass‐specific activity of 109.80 mA/mgAg, which is about 6.4 times that of pure rhombic dodecahedron‐Ag3PO4/C catalyst (17.20 mA/mgAg). The density functional theory (DFT) calculation based on the density of states (DOS) further proved the optimal tunable effect, which is in pace with demonstration of electron transfer direction revealed by X‐ray photoelectron spectroscopy (XPS) analysis. Our work establishes a theoretical and practical basis for the rational design of newly non‐Pt hybrid catalysts, moreover, advances the future efficient application of PEMFCs.A cost effective electronically coupled semiconductor heterojunction between facet‐Ag3PO4 and Cu2O cube is reported. Its high electrocatalytic activity towards oxygen reduction reaction (ORR) indicates that electron distribution can be controlled through the interfacial engineering between Ag3PO4 and Cu2O. This paves way to rationally design new non‐Pt hybrid catalysts, and moreover advances the future efficient applications of proton exchange membrane fuel cells (PEMFCs).Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149290/1/slct201900615.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149290/2/slct201900615-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149290/3/slct201900615_am.pd

Abnormal function of EPHA2/p.R957P mutant in congenital cataract

AIM: To identify genetic defects in a Chinese family with congenital posterior polar cataracts and assess the pathogenicity. METHODS: A four-generation Chinese family affected with autosomal dominant congenital cataract was recruited. Nineteen individuals took part in this study including 5 affected and 14 unaffected individuals. Sanger sequencing targeted hot-spot regions of 27 congenital cataract-causing genes for variant discovery. The pathogenicity of the variant was evaluated by the guidelines of American College of Medical Genetics and InterVar software. Confocal microscopy was applied to detect the subcellular localization of fluorescence-labeled ephrin type-A receptor 2 (EPHA2). Co-immunoprecipitation assay was implemented to estimate the interaction between EphA2 and other lens membrane proteins. The mRNA and protein expression were analyzed by reverse transcription-polymerase chain reaction (qRT-PCR) and Western blotting assay, respectively. The cell migration was analyzed by wound healing assay. Zebrafish model was generated by ectopic expression of human EPHA2/p.R957P mutant to demonstrate whether the mutant could cause lens opacity in vivo. RESULTS: A novel missense and pathogenic variant c.2870G>C was identified in the sterile alpha motif (SAM) domain of EPHA2. Functional studies demonstrated the variant's impact: reduced EPHA2 protein expression, altered subcellular localization, and disrupted interactions with other lens membrane proteins. This mutant notably enhanced human lens epithelial cell migration, and induced a central cloudy region and roughness in zebrafish lenses with ectopic expression of human EPHA2/p.R957P mutant under differential interference contrast (DIC) optics. CONCLUSION: Novel pathogenic c.2870G>C variant of EPHA2 in a Chinese congenital cataract family contributes to disease pathogenesis