Fe-based double perovskite with Zn doping for enhanced electrochemical performance as intermediate-temperature solid oxide fuel cell cathode material.

This study aims to investigate the implications of transition-metal Zn doping at the B-site on the crystal structure, average thermal expansion coefficient (TEC), electrocatalytic activity, and electrochemical performance of LaBaFe2O5+δ by preparing LaBaFe2-xZnxO5+δ (x = 0, 0.05, 0.1, 0.15, 0.2, LBFZx). The X-ray diffraction (XRD) results show that Zn2+ doping does not change the crystal structure, the unit cell volume increases, and the lattice expands. The X-ray photoelectron spectroscopy (XPS) and mineral titration results show that the oxygen vacancy concentration and Fe4+ content gradually increase with the increase in doping amount. TEC decreases with the increase in Zn2+ doping amount, and the TEC of LBFZ0.2 is 11.4 × 10-6 K-1 at 30-750 °C. The conductivity has the best value of 103 S cm-1 at the doping amount of x = 0.1. The scanning electron microscopy (SEM) images demonstrate that the electrolyte CGO(Gd0.1Ce0.9O1.95) becomes denser after high-temperature calcination, and the cathode material is well attached to the electrolyte. The electrochemical impedance analysis shows that Zn2+ doping at the B-site can reduce the (Rp) polarization resistance, and the Rp value of the symmetric cell with LaBaFe1.8Zn0.2O5+δ as cathode at 800 °C is 0.014 Ω cm2. The peak power density (PPD) value of the anode-supported single cell is 453 mW cm-2, which shows excellent electrochemical performance.

Endoscopic grading of gastric atrophy and histological gastritis staging on risk assessment for early gastric cancer: A case-control study.

OBJECTIVES: To assess the predictive value of endoscopic grading of gastric atrophy using Kimura-Takemoto classification, histological grading systems of operative link on gastritis assessment (OLGA) and operative link on gastric intestinal metaplasia (OLGIM) on risk stratification for early gastric cancer (EGC) and other potential risk factors of EGC. METHODS: A single-center, case-control study was retrospectively conducted including 68 patients with EGC treated with endoscopic submucosal dissection and 68 age- and sex-matched control subjects. Kimura-Takemoto classification, OLGA and OLGIM systems, and other potential risk factors were evaluated between the two groups. RESULTS: Of the 68 EGC lesions, 22 (32.4%) were well differentiated, 38 (55.9%) were moderately differentiated, and 8 (11.8%) were poorly differentiated, respectively. Multivariate analysis revealed O-type Kimura-Takemoto classification (adjusted odds ratio [AOR] 3.282, 95% confidence interval [CI] 1.106-9.744, P = 0.032) and OLGIM stage III/IV (AOR 17.939, 95% CI 1.874-171.722, P = 0.012) were significantly related to a higher risk of EGC. Especially, O-type Kimura-Takemoto classification within 6-12 months before EGC diagnosis (AOR 4.780, 95% CI 1.650-13.845, P = 0.004) was independently associated with EGC risk. Areas under the receiver operating characteristic curve of the three systems for EGC were comparable. CONCLUSIONS: Endoscopic Kimura-Takemoto classification and histological OLGIM stage III/IV are independent risk factors for EGC, which may reduce the need for biopsies in risk stratification of EGC. Further multicenter prospective studies of large sizes are needed.

Electric pulse stimulation inhibited lipid accumulation on C2C12 myotubes incubated with oleic acid and palmitic acid.

OBJECTIVE: To investigate the effect of electrical pulse stimulation (EPS) on lipid accumulation and alteration of fatty acid-related enzymes in C2C12 myotubes incubated with fatty acids. METHODS: Mouse C2C12 myotubes were incubated with oleic acid and palmitic acid, and differentiated C2C12 myotubes were treated with EPS, oil-red O (ORO), BODIPY staining and triglyceride (TG) content were examined. Total RNA was isolated, and real-time polymerase chain reaction analysis was performed. RESULTS: (1) EPS decreased TG content (p < .01). (2) EPS significantly induced the mRNA expression of FAD/CD36 (p < .05), FATP4 (p < .001), FABP1 (p < .01) and FABP5 (p < .01). (3) EPS significantly inhibited the mRNA expression of fatty acid synthase (p < .01). (4) Adipose triglyceride lipase and hormone-sensitive lipase expression were significantly elevated (p < .001), and induced the mRNA expression of CPT1 (p < .01), ACOX1 (p < .05), UCP3 (p < .05) and PPARα (p < .001) after EPS. CONCLUSION: EPS reduced lipid droplet accumulation; enhanced CD36, FATP4, FABP1 and FABP5 expression; inhibited C2C12 myotube fatty acid re-esterification; and promoted fatty acid oxidation in C2C12 myotubes.

Observation of inhomogeneous plasmonic field distribution in a nanocavity.

The progress of plasmon-based technologies relies on an understanding of the properties of the enhanced electromagnetic fields generated by the coupling nanostrucutres1-6. Plasmon-enhanced applications include advanced spectroscopies7-10, optomechanics11, optomagnetics12 and biosensing13-17. However, precise determination of plasmon field intensity distribution within a nanogap remains challenging. Here, we demonstrate a molecular ruler made from a set of viologen-based, self-assembly monolayers with which we precisely measures field distribution within a plasmon nanocavity with ~2-Å spatial resolution. We observed an unusually large plasmon field intensity inhomogeneity that we attribute to the formation of a plasmonic comb in the nanocavity. As a consequence, we posit that the generally adopted continuous media approximation for molecular monolayers should be used carefully.

Vascular endothelial growth factor B inhibits lipid accumulation in C2C12 myotubes incubated with fatty acids.

To investigate (1) the effect of vascular endothelial growth factor B (VEGFB) on lipid accumulation and the alteration of fatty acids and fatty acid-related enzymes in C2C12 myotubes incubated with fatty acids and (2) the regulatory effect of VEGFB on skeletal muscle lipid metabolism. Mouse C2C12 myotubes were incubated with oleic acid (OA) and palmitic acid (PA), and differentiated mature C2C12 myotubes were treated with VEGFB. Oil-red O staining, BODIPY staining and cell triglycerides (TG) content were examined. Total RNA was isolated, and real-time PCR analysis was performed. Treatment with 100 µM OA and 50 µM PA induced lipid droplet accumulation and increased TG content (p < .01), and 100 ng/mL VEGFB reduced lipid droplet accumulation and decreased TG content (p < .01). Treatment with 100 ng/mL VEGFB significantly induced the mRNA expression of fatty acid transport protein 1 (FATP1) (p < .01) and FATP4 (p < .01). Treatment with 100 ng/mL VEGFB significantly induced the mRNA expression of adipose TG lipase and hormone-sensitive lipase (p < .01) as well as carnitine palmitoyltransferase I (p < .01), peroxisome proliferator-activated receptor-γ coactivator-1α (p < .01), acyl-coa dehydrogenase very long chain (p < .05), acyl-coa synthetase long-chain family member 1 (p < .01), peroxisomal acyl-coenzyme A oxidase 1 (p < .05), and mitochondrial uncoupling protein 3 (p < .01). VEGFB enhanced FATP1and FATP4 expression, promoted C2C12 myotube fatty acid oxidation and TG decomposition, and inhibited C2C12 myotube fatty acid re-esterification, thus inhibiting lipid accumulation in C2C12 myotubes incubated with fatty acids.

Genus-Wide Comparative Genomics Analysis of Neisseria to Identify New Genes Associated with Pathogenicity and Niche Adaptation of Neisseria Pathogens.

N. gonorrhoeae and N. meningitidis, the only two human pathogens of Neisseria, are closely related species. But the niches they survived in and their pathogenic characteristics are distinctly different. However, the genetic basis of these differences has not yet been fully elucidated. In this study, comparative genomics analysis was performed based on 15 N. gonorrhoeae, 75 N. meningitidis, and 7 nonpathogenic Neisseria genomes. Core-pangenome analysis found 1111 conserved gene families among them, and each of these species groups had opening pangenome. We found that 452, 78, and 319 gene families were unique in N. gonorrhoeae, N. meningitidis, and both of them, respectively. Those unique gene families were regarded as candidates that related to their pathogenicity and niche adaptation. The relationships among them have been partly verified by functional annotation analysis. But at least one-third genes for each gene set have not found the certain functional information. Simple sequence repeat (SSR), the basis of gene phase variation, was found abundant in the membrane or related genes of each unique gene set, which may facilitate their adaptation to variable host environments. Protein-protein interaction (PPI) analysis found at least five distinct PPI clusters in N. gonorrhoeae and four in N. meningitides, and 167 and 52 proteins with unknown function were contained within them, respectively.

rhPLD2 inhibits airway inflammation in an asthmatic murine model through induction of stable CD25+ Foxp3+ Tregs.

Our previous studies have shown that recombinant human phospholipase D2 (rhPLD2) plays a modulator role on NF-κB and PKC signaling pathways. It also inhibits IL-5-induced inflammatory response in chronic asthmatic guinea pigs. Additionally, increasing evidence also has revealed that the adoptive transfer of induced regulatory T cells (Tregs) may be a therapeutic solution to airway allergic diseases. To investigate the epigenetic, transcriptomic and phenotypic variability of Treg population in an ovalbumin (OVA)-induced airway inflammation model derived from the induction of rhPLD2, OVA-induced asthmatic murine model is used in this study. The lung inflammation, eosinophil infiltration, the differentiation and proliferation of T helper cells and the amplification of Tregs were examined in this mouse model with and without rhPLD2 induction. Our data showed that rhPLD2 administration in asthmatic mice significantly increases CD4+CD25+ Foxp3+ Treg cell numbers and alleviates lung inflammation. The addition of rhPLD2 in vitro enhanced the demethylation of Treg-specificdemethylated region (TSDR) in iTregs, suggesting that rhPLD2 protein may be involved in improving the quality and quantity of Treg cells that eventually significantly reduces lung inflammation in asthmatic murine model. These results suggest that rhPLD2 could have a clinical impact treating patients with allergic airway inflammation via promoting and stabilizing iTreg differentiation and function.

Comparative Genomics of H. pylori and Non-Pylori Helicobacter Species to Identify New Regions Associated with Its Pathogenicity and Adaptability.

The genus Helicobacter is a group of Gram-negative, helical-shaped pathogens consisting of at least 36 bacterial species. Helicobacter pylori (H. pylori), infecting more than 50% of the human population, is considered as the major cause of gastritis, peptic ulcer, and gastric cancer. However, the genetic underpinnings of H. pylori that are responsible for its large scale epidemic and gastrointestinal environment adaption within human beings remain unclear. Core-pan genome analysis was performed among 75 representative H. pylori and 24 non-pylori Helicobacter genomes. There were 1173 conserved protein families of H. pylori and 673 of all 99 Helicobacter genus strains. We found 79 genome unique regions, a total of 202,359bp, shared by at least 80% of the H. pylori but lacked in non-pylori Helicobacter species. The operons, genes, and sRNAs within the H. pylori unique regions were considered as potential ones associated with its pathogenicity and adaptability, and the relativity among them has been partially confirmed by functional annotation analysis. However, functions of at least 54 genes and 10 sRNAs were still unclear. Our analysis of protein-protein interaction showed that 30 genes within them may have the cooperation relationship.

[Surgical treatment for terrible triad of the elbow through medial and lateral approach].

OBJECTIVE: To investigate the clinical effects of medial and lateral approach in treating terrible triad of the elbow. METHODS: From May 2010 from May 2014, 11 patients with terrible triad of the elbow were treated through medial and lateral approach. There were 6 males and 5 females, aged from 25 to 56 years with an average of 35.2 years old. The time from injury to operation was from 1 to 13 days with an average of 5.9 days. Fracture of radial head according to Mason typing, 2 cases were type I, 7 cases were type II, 2 cases were type III. Ulnar coronoid fracture according to Regan-Morrey typing, 3 cases were type I, 7 cases were type II, 1 case was type III. Postoperative complications were observed and Mayo elbow performance score(MEPS) was used to assess the elbow joint function. RESULTS: All patients were followed up from 6 to 24 months with an average of 15.5 months. All fractures obtained healing with an average time of 14 weeks (ranged from 10 to 18 weeks). According to Mayo to assess the results, total score was 78.2±11.7, 2 cases got excellent results, 7 good, 1 fair, 1 poor. At final follow up, the mean range of motion was (108±21)° in flexion, (12±8)° in extension, (66±13)° in pronation, (28±18)° in supination. The varus angle of the elbow ranged from 5°to 8° in 3 cases and the valgus angle was 8° in 1 case. CONCLUSIONS: Treatment of the terrible triad of the elbow through medial and lateral approach can obtain satisfactory clinical effects, restore the elbow stability, allow early motion postoperatively, and promote the joint functional rehabilitation.

Quantitative SHINERS analysis of temporal changes in the passive layer at a gold electrode surface in a thiosulfate solution.

Shell-isolated gold nanoparticles (SHINs) were employed to record shell-isolated nanoparticle-enhanced Raman spectra (SHINERS) of a passive layer formed at a gold surface during gold leaching from thiosulfate solutions. The (3-aminopropyl)triethoxysilane (APTES) and a sodium silicate solution were used to coat gold nanoparticles with a protective silica layer. This protective silica layer prevented interactions between the thiosulfate electrolyte and the gold core of the SHINs when the SHINs-modified gold electrode was immersed into the thiosulfate lixiviant. The SHINERS spectra of the passive layer, formed from thiosulfate decomposition, contained bands indicative of hydrolyzed APTES. We have demonstrated how to exploit the presence of these APTES bands as an internal standard to compensate for fluctuations of the surface enhancement of the electric field of the photon. We have also developed a procedure that allows for removal of the interfering APTES bands from the SHINERS spectra. These methodological advancements have enabled us to identify the species forming the passive layer and to determine that the formation of elemental sulfur, cyclo-S8, and polymeric sulfur chains is responsible for inhibition of gold dissolution in oxygen rich thiosulfate solutions.

Electrochemical shell-isolated nanoparticle-enhanced Raman spectroscopy: correlating structural information and adsorption processes of pyridine at the Au(hkl) single crystal/solution interface.

Electrochemical methods are combined with shell-isolated nanoparticle-enhanced Raman spectroscopy (EC-SHINERS) for a comprehensive study of pyridine adsorption on Au(111), Au(100) and Au(110) single crystal electrode surfaces. The effects of crystallographic orientation, pyridine concentration, and applied potential are elucidated, and the formation of a second pyridine adlayer on Au(111) is observed spectroscopically for the first time. Electrochemical and SHINERS results correlate extremely well throughout this study, and we demonstrate the potential of EC-SHINERS for thorough characterization of processes occurring on single crystal surfaces. Our method is expected to open up many new possibilities in surface science, electrochemistry and catalysis. Analytical figures of merit are discussed.

Surface analysis using shell-isolated nanoparticle-enhanced Raman spectroscopy.

Surface-enhanced Raman scattering (SERS) is a powerful fingerprint vibrational spectroscopy with a single-molecule detection limit, but its applications are generally restricted to 'free-electron-like' metal substrates such as Au, Ag and Cu nanostructures. We have invented a shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) technique, using Au-core silica-shell nanoparticles (Au@SiO(2) NPs), which makes SERS universally applicable to surfaces with any composition and any morphology. This protocol describes how to prepare shell-isolated nanoparticles (SHINs) with different well-controlled core sizes (55 and 120 nm), shapes (nanospheres, nanorods and nanocubes) and shell thicknesses (1-20 nm). It then describes how to apply SHINs to Pt and Au single-crystal surfaces with different facets in an electrochemical environment, on Si wafer surfaces adsorbed with hydrogen, on ZnO nanorods, and on living bacteria and fruit. With this method, SHINs can be prepared for use in ~3 h, and each subsequent procedure for SHINERS measurement requires 1-2 h.

Synthesis, characterization, and 3D-FDTD simulation of Ag@SiO2 nanoparticles for shell-isolated nanoparticle-enhanced Raman spectroscopy.

Au-seed Ag-growth nanoparticles of controllable diameter (50-100 nm), and having an ultrathin SiO(2) shell of controllable thickness (2-3 nm), were prepared for shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS). Their morphological, optical, and material properties were characterized; and their potential for use as a versatile Raman signal amplifier was investigated experimentally using pyridine as a probe molecule and theoretically by the three-dimensional finite-difference time-domain (3D-FDTD) method. We show that a SiO(2) shell as thin as 2 nm can be synthesized pinhole-free on the Ag surface of a nanoparticle, which then becomes the core. The dielectric SiO(2) shell serves to isolate the Raman-signal enhancing core and prevent it from interfering with the system under study. The SiO(2) shell also hinders oxidation of the Ag surface and nanoparticle aggregation. It significantly improves the stability and reproducibility of surface-enhanced Raman scattering (SERS) signal intensity, which is essential for SERS applications. Our 3D-FDTD simulations show that Ag-core SHINERS nanoparticles yield at least 2 orders of magnitude greater enhancement than Au-core ones when excited with green light on a smooth Ag surface, and thus add to the versatility of our SHINERS method.

Rapid visual detection of aluminium ion using citrate capped gold nanoparticles.

We report the visual detection of Al(3+) using unlabeled gold nanoparticles (AuNPs) based on the complexation of Al(3+) with citric acid, resulting in the aggregation of AuNPs. The distinction of color change can be observed by the naked eye at concentrations down to 1.0 µM which is lower than the permissable level (7.4 µM) for drinking water as defined by the World Health Organization.

[Cathodoluminescent properties of Na2GdPO4F2:Tb3+ green phosphors].

The green emitting phosphors, Na2GdPO4F2:Tb3+, was synthesized by high temperature solid-state method. X-ray diffraction (XRD) and cathodoluminescence (CL) spectrum were used to characterize the samples. Under the low-voltage electron beam (0.5 - 5 kV) excitation, the Tb3+-doped Na2GdPO4F2 phosphor showed a very strong green emission corresponding to the characteristic transitions of Tb3+ (5D3,4 --> F(J) transitions, J = 6 - 2) with the strongest emission at 546 nm, corresponding to 5D4 --> F5 of Tb3+. The cathodoluminescent color of Na2Gd0.95Tb0.05PO4F2 was green to the naked eye with the Commission International de l'Eclairage (CIE) coordinates of x = 0.2403, y = 0.4386, and the color temperature at about 8634.3 K. The CL intensity increases upon raising the accelerating voltage, filament current and the doping concentrations, thereinto, the optimal concentrations of Tb3+ is 10 mol%.

Synthesis and characterization of gold nanoparticles coated with ultrathin and chemically inert dielectric shells for SHINERS applications.

We very recently reported a new spectroscopic application for expanding the versatility of surface Raman called "shell-isolated nanoparticle-enhanced Raman spectroscopy" or "SHINERS". The most important and most difficult part of the SHINERS experiment is the effective transfer of the strong electromagnetic field from a gold core through the isolating silica or alumina shell to the probed surface. For this it is essential that the chemically inert dielectric shell be ultrathin (2-5 nm) yet pinhole-free. Herein we describe experimental and theoretical aspects of our SHINERS method in more detail. We provide a protocol for the synthesis and characterization of optimized shell-isolated nanoparticles (SHINs), and we examine the advantages of SHINERS nanoparticles over bare gold nanoparticles. We also present high-quality Raman spectra obtained from gold and platinum single-crystal surfaces in an electrochemical environment by our SHINERS technique. SHINERS is a simple and cost-effective approach that expands the flexibility of surface-enhanced Raman scattering (SERS) for an unprecedented diversity of applications in materials and surface sciences.

[Photoluminescence of green phosphors Gd2Ba3B3O12 doped with Tb3+].

The green emitting phosphor, Gd2Ba3B3O12:Tb3+ was synthesized with the method of high-temperature solid-state reaction. The phase structure and photoluminescence (PL) properties of the samples were characterized by The X-ray diffraction (XRD), vacuum ultraviolet spectrum and ultraviolet spectrum (VUV-UV). The results indicate that Tb3+ ion acting as the luminescent center inhabited the site of Gd3+ ion in the host of Gd2Ba3B3O12. The VUV-UV excitation spectrum consists of the two strong broad bands at about 160-200 and 200-250 nm and sharp lines at about 260-280 and 300-320 nm. The two strong broad bands were assigned to the host absorption and f--d transition of Tb3+. The sharp lines were ascribed to the f--f transition of Tb3+ and Gd3+. All the samples of Gd2Ba3B3O12:Tb3+ exhibit strong green emission corresponding to (5)D4-->(7)F5 transition (543 nm) of Tb3+ under VUV-UV light excitation. Under 172 nm excitation, 15 mol% Tb3+ doped Gd2Ba3B3O12 sample exhibits strong green emission with good color purity (x = 0.3136, y = 0.4843) and a fitted a decay time r around 2.98 ms. It can be concluded that this series of phosphors Gd2Ba3B3O12:Tb3+ is a promising green vacuum ultraviolet (VUV) phosphor for plasma display panels (PDPs) and Hg-free fluorescent tubes application.

Shell-isolated nanoparticle-enhanced Raman spectroscopy.

Surface-enhanced Raman scattering (SERS) is a powerful spectroscopy technique that can provide non-destructive and ultra-sensitive characterization down to single molecular level, comparable to single-molecule fluorescence spectroscopy. However, generally substrates based on metals such as Ag, Au and Cu, either with roughened surfaces or in the form of nanoparticles, are required to realise a substantial SERS effect, and this has severely limited the breadth of practical applications of SERS. A number of approaches have extended the technique to non-traditional substrates, most notably tip-enhanced Raman spectroscopy (TERS) where the probed substance (molecule or material surface) can be on a generic substrate and where a nanoscale gold tip above the substrate acts as the Raman signal amplifier. The drawback is that the total Raman scattering signal from the tip area is rather weak, thus limiting TERS studies to molecules with large Raman cross-sections. Here, we report an approach, which we name shell-isolated nanoparticle-enhanced Raman spectroscopy, in which the Raman signal amplification is provided by gold nanoparticles with an ultrathin silica or alumina shell. A monolayer of such nanoparticles is spread as 'smart dust' over the surface that is to be probed. The ultrathin coating keeps the nanoparticles from agglomerating, separates them from direct contact with the probed material and allows the nanoparticles to conform to different contours of substrates. High-quality Raman spectra were obtained on various molecules adsorbed at Pt and Au single-crystal surfaces and from Si surfaces with hydrogen monolayers. These measurements and our studies on yeast cells and citrus fruits with pesticide residues illustrate that our method significantly expands the flexibility of SERS for useful applications in the materials and life sciences, as well as for the inspection of food safety, drugs, explosives and environment pollutants.

[Comparison of therapeutic effects of low-dose versus high-dose interferon alpha-2b treatment on chronic myelocytic leukemia: a prospective randomized study].

OBJECTIVE: To compare the therapeutic effects of low-dose and high-dose interferon alpha-2b (IFN) treatment on chronic myelocytic leukemia (CML). METHODS: A real-time quantitative reverse transcriptase PCR (RQ-PCR) method was established to detect the fusion gene bcr-abl expression, thereby studying the reduction of leukemic cells. Thirty newly diagnosed CML patients, 21 males and 9 females, aged 14 - 69, were treated with hydroxyurea to keep the white blood cell count less than 20 x 10(9)/L, and then randomized into 2 groups: high-dose IFN group receiving IFN alpha-2b 5MIU 6 times per week for 3 - 6 months and low-dose IFN group receiving IFN alpha-2b 3MIU every other day for 3 - 6 months. Bone marrow was collected every month to Real-time PCR was used to detect the expression of bcr-abl mRNA. Mononuclear cells were isolated and RNA was extracted to detect the expression of fusion gene bcr-abl and a control gene GAPDH. The results were reported as the number of bcr-abl copies/GAPDH copy. RESULTS: The established real-time quantitative PCR method could detect the bcr-abl molecules as low as 50 copies. The intra-assay coefficient of variation (CV) was less than 5% and the inter-assay CV was 5.13%. The median bcr-abl fusion gene expression level of 30 CML patients before IFN therapy was 0.098 (range: 0.010 - 5.799). The bcr-abl expression level decreased by 19.37% and 24.86% in the low-dose and high-dose IFN groups respectively after 3 months' therapy. No significant difference was observed between the two groups (P = 0.398). Relatively more side effects were observed in the high-dose IFN group than in low-dose group. CONCLUSION: RQ-PCR is a reliable method to monitor CML therapy by analyzing fusion gene bcr-abl expression. There is a difference in bcr-abl fusion gene expression levels among the newly diagnosed patients, and low-dose IFN is as effective as high-dose IFN in reducing bcr-abl expression but with less side effects.