Synthesis and characterization of polypyrrole doped with anionic spherical polyelectrolyte brushes

The procedures for the synthesis of polypyrrole (PPy) doped with anionic spherical polyelectrolyte brushes (ASPB) (PPy/ASPB nanocomposite) by means of in situ chemical oxidative polymerization were presented. Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopic analysis suggested the bonding structure of PPy/ASPB nanocomposite. Scanning electron microscopy (SEM) was used to confirm the morphologies of samples. The crystallographic structure, chemical nature and thermal stability of conducting polymers were analyzed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Thermo-gravimetric analysis (TGA) respectively. Investigation of the electrical conductivity at room temperature showed that the electrical conductivity of PPy/ASPB nanocomposite was 20 S/cm, which was higher than that of PPy (3.6 S/cm)

Dietary Diversity Was Positively Associated with Psychological Resilience among Elders: A Population-Based Study

The association between dietary diversity (DD) and psychological resilience among older people is an underdeveloped area of research. This cross-sectional study explored the associations of DD with psychological resilience among 8571 community-based elderly individuals. The intake frequencies of food groups were collected, and dietary diversity was assessed based on the mean DD score. Psychological resilience was assessed using a simplified resilience score (SRS). Data were analyzed using multiple linear regression and logistic regression models. Poor DD was significantly associated with psychological resilience, with a β (95% CI) of −0.94 (−1.07, −0.81) for the SRS (p \u3c 0.01) and an odds ratio (95% CI) of 1.83 (1.66, 2.01) for low SRS status. The interaction effects of age with DD were observed for the SRS (p \u3c 0.001) and low SRS status (p \u3c 0.001). Based on separate analyses by age group, the association of a low SRS with poor DD was more prominent in the younger elderly than the oldest old, with OR (95% CI) 2.32 (1.96, 2.74) and 1.61 (1.43, 1.82), respectively. Compared with younger participants with good DD, the risk of a low SRS was greater for younger participants with poor DD, the oldest old with good DD, and the oldest old with poor DD, with OR (95% CI) 2.39 (2.02, 2.81), 1.28 (1.09, 1.51), and 2.03 (1.72, 2.39), respectively. The greatest contribution to DD was from a high consumption of vegetables, fruits, and nuts. Our study suggested that poor DD was associated with a low psychological resilience among the Chinese elderly, especially the younger elderly. These findings suggest that augmentation of DD might promote psychological resilience

Carbon-doped ZnO: A New Class of Room Temperature Dilute Magnetic Semiconductor

We report magnetism in carbon doped ZnO. Our first-principles calculations based on density functional theory predicted that carbon substitution for oxygen in ZnO results in a magnetic moment of 1.78 $\mu_B$ per carbon. The theoretical prediction was confirmed experimentally. C-doped ZnO films deposited by pulsed laser deposition with various carbon concentrations showed ferromagnetism with Curie temperatures higher than 400 K, and the measured magnetic moment based on the content of carbide in the films ($1.5 - 3.0 \mu_B$ per carbon) is in agreement with the theoretical prediction. The magnetism is due to bonding coupling between Zn ions and doped C atoms. Results of magneto-resistance and abnormal Hall effect show that the doped films are $n$-type semiconductors with intrinsic ferromagnetism. The carbon doped ZnO could be a promising room temperature dilute magnetic semiconductor (DMS) and our work demonstrates possiblity of produing DMS with non-metal doping.Comment: REVtex source with 4 figures in eps forma

Single chargino production via gluon-gluon fusion in a supersymmetric theory with an explicit R-parity violation

We studied the production of single chargino$\tilde{\chi}_1^{\pm}$ accompanied by $\mu^{\mp}$ lepton via gluon-gluon fusion at the LHC. The numerical analysis of their production rates is carried out in the mSUGRA scenario with some typical parameter sets. The results show that the cross sections of the $\tilde{\chi}_1^{\pm}\mu^{\mp}$ productions via gluon-gluon collision are in the order of $1 \sim 10^{2}$ femto barn quantitatively at the CERN LHC, and can be competitive with production mechanism via quark-antiquark annihilation process.Comment: LaTex file, 18 pages, 4 EPS file

Metabolic labelling of cholesteryl glucosides in Helicobacter pylori reveals how the uptake of human lipids enhances bacterial virulence.

Helicobacter pylori infects approximately half of the human population and is the main cause of various gastric diseases. This pathogen is auxotrophic for cholesterol, which it converts upon uptake to various cholesteryl α-glucoside derivatives, including cholesteryl 6'-acyl and 6'-phosphatidyl α-glucosides (CAGs and CPGs). Owing to a lack of sensitive analytical methods, it is not known if CAGs and CPGs play distinct physiological roles or how the acyl chain component affects function. Herein we established a metabolite-labelling method for characterising these derivatives qualitatively and quantitatively with a femtomolar detection limit. The development generated an MS/MS database of CGds, allowing for profiling of all the cholesterol-derived metabolites. The subsequent analysis led to the unprecedented information that these bacteria acquire phospholipids from the membrane of epithelial cells for CAG biosynthesis. The resulting increase in longer or/and unsaturated CAG acyl chains helps to promote lipid raft formation and thus delivery of the virulence factor CagA into the host cell, supporting the idea that the host/pathogen interplay enhances bacterial virulence. These findings demonstrate an important connection between the chain length of CAGs and the bacterial pathogenicity

A novel deep intronic variant strongly associates with Alkaptonuria.

Alkaptonuria is a rare autosomal recessive inherited disorder of tyrosine metabolism, which causes ochronosis, arthropathy, cardiac valvular calcification, and urolithiasis. The epidemiology of alkaptonuria in East Asia is not clear. In this study, patients diagnosed with alkaptonuria from January 2010 to June 2020 were reviewed. Their clinical and molecular features were further compared with those of patients from other countries. Three patients were found to have alkaptonuria. Mutation analyses of the homogentisate 1,2-dioxygenase gene (HGD) showed four novel variants c.16-2063 A > C, p.(Thr196Ile), p.(Gly344AspfsTer25), and p.(Gly362Arg) in six mutated alleles (83.3%). RNA sequencing revealed that c.16-2063 A > C activates a cryptic exon, causing protein truncation p.(Tyr5_Ile6insValTer17). A literature search identified another 6 patients with alkaptonuria in East Asia; including our cases, 13 of the 18 mutated alleles have not been reported elsewhere in the world. Alkaptonuria is rare in Taiwan and East Asia, with HGD variants being mostly novel and private

Lanthanum distribution and dielectric properties of intergrowth Bi₅ˍₓLaₓTiNbWO₁₅ ferroelectrics

Bi₅ˍₓLaₓTiNbWO₁₅ (x=0–1.50)ceramics prepared by conventional solid-state reaction were studied using x-ray diffraction(XRD),dielectric spectroscopy and Raman scattering techniques. The XRD analysis implied that single-phase intergrowth bismuth layered perovskite structure was obtained for all the samples and when x=0.75, the Bi³⁺ in (Bi₂O₂)²⁺ layer begins to be substituted by La³⁺. The dielectric spectra showed that, when Bi³⁺ in (Bi₂O₂)²⁺ is substituted, the Curie temperature becomes diffusive and the dielectricpermittivity at room temperature is increased in a wide frequency range. Especially when x=1.50, the dielectricpermittivity reaches its maximum of 270, nearly two times larger than that of the La3+ undoped sample. The Raman scattering experiments evidenced further that Bi³⁺ in (Bi₂O₂)²⁺ is substituted when x⩾0.75 and revealed the orthorhombic distortion of the octahedra is responsible for the increase of the dielectricpermittivity at x⩾1.25.This work was supported by the Ministry of Science and Technology of China through 973-Project under Grant No. 2002CB613307

Excitation of superconducting qubits from hot non-equilibrium quasiparticles

Superconducting qubits probe environmental defects such as non-equilibrium quasiparticles, an important source of decoherence. We show that "hot" non-equilibrium quasiparticles, with energies above the superconducting gap, affect qubits differently from quasiparticles at the gap, implying qubits can probe the dynamic quasiparticle energy distribution. For hot quasiparticles, we predict a non-neligable increase in the qubit excited state probability P_e. By injecting hot quasiparticles into a qubit, we experimentally measure an increase of P_e in semi-quantitative agreement with the model and rule out the typically assumed thermal distribution.Comment: Main paper: 5 pages, 5 figures. Supplement: 1 page, 1 figure, 1 table. Updated to user-prepared accepted version. Key changes: Supplement added, Introduction rewritten, Figs.2,3,5 revised, Fig.4 adde