Pulsed Laser Deposition of Rocksalt Magnetic Binary Oxides

Here we systematically explore the use of pulsed laser deposition technique (PLD) to grow three basic oxides that have rocksalt structure but different chemical stability in the ambient atmosphere: NiO (stable), MnO (metastable) and EuO (unstable). By tuning laser fluence, an epitaxial single-phase nickel oxide thin-film growth can be achieved in a wide range of temperatures from 10 to 750 {\deg}C. At the lowest growth temperature, the out-of-plane strain raises to 1.5%, which is five times bigger than that in a NiO film grown at 750 {\deg}C. MnO thin films that had long-range ordered were successfully deposited on the MgO substrates after appropriate tuning of deposition parameters. The growth of MnO phase was strongly influenced by substrate temperature and laser fluence. EuO films with satisfactory quality were deposited by PLD after oxygen availability had been minimized. Synthesis of EuO thin films at rather low growth temperature prevented thermally-driven lattice relaxation and allowed growth of strained films. Overall, PLD was a quick and reliable method to grow binary oxides with rocksalt structure in high quality that can satisfy requirements for applications and for basic research

Biomarkers of Oxidative Stress and Endogenous Antioxidants for Patients with Chronic Subjective Dizziness

As a neurotologic disorder of persistent non-vertiginous dizziness, chronic subjective dizziness (CSD) arises unsteadily by psychological and physiological imbalance. The CSD is hypersensitivity reaction due to exposure to complex motions visual stimuli. However, the pathophysiological features and mechanism of the CSD still remains unclearly. The present study was purposed to establish possible endogenous contributors of the CSD using serum samples from patients with the CSD. A total 199 participants were gathered and divided into two groups; healthy (n = 152, male for 61, and female for 91) and CSD (n = 47, male for 5, female for 42), respectively. Oxidative stress parameters such as, hydrogen peroxide and reactive substances were significantly elevated (p < 0.01 or p < 0.001), whereas endogenous antioxidant components including total glutathione contents, and activities of catalase and superoxide dismutase were significantly deteriorated in the CSD group (p < 0.01 or p < 0.001) as comparing to the healthy group, respectively. Serum levels of tumor necrosis factor -α and interferon-γ were significantly increased in the CSD participants (p < 0.001). Additionally, emotional stress related hormones including cortisol, adrenaline, and serotonin were abnormally observed in the serum levels of the CSD group (p < 0.01 or p < 0.001). Our results confirmed that oxidative stress and antioxidants are a critical contributor of pathophysiology of the CSD, and that is first explored to establish features of redox system in the CSD subjects compared to a healthy population

Downregulation of protein kinase CK2 activity induces age-related biomarkers in C. elegans

Studies show that a decrease in protein kinase CK2 (CK2) activity is associated with cellular senescence. However, the role of CK2 in organism aging is still poorly understood. Here, we investigated whether protein kinase CK2 (CK2) modulated longevity in Caenorhabditis elegans. CK2 activity decreased with advancing age in the worms. Knockdown of kin-10 (the ortholog of CK2 beta) led to a short lifespan phenotype and induced age-related biomarkers, including retardation of locomotion, decreased pharyngeal pumping rate, increased lipofuscin accumulation, and reduced resistance to heat and oxidative stress. The long lifespan of age-1 and akt-1 mutants was significantly suppressed by kin-10 RNAi, suggesting that CK2 acts downstream of AGE-1 and AKT-1. Kin-10 knockdown did not further shorten the short lifespan of daf-16 mutant worms but either decreased or increased the transcriptional activity of DAF-16 depending on the promoters of the target genes, indicating that CK2 is an upstream regulator of DAF-16 in C. elegans. Kin-10 knockdown increased production of reactive oxygen species (ROS) in the worms. Finally, the ROS scavenger N-acetyl-L-cysteine significantly counteracts the lifespan shortening and lipofuscin accumulation induced by kin-10 knockdown. Therefore, the present results suggest that age-dependent CK2 downregulation reduces longevity by associating with both ROS generation and the AGE-1-AKT-1-DAF-16 pathway in C. elegans. © Copyright 2017 Elsevier B.V., All rights reserved.1111sci

Surface Sr segregation behaviors in a model thin film perovskite cathode for solid oxide fuel cells

Surface cation segregation, strontium (Sr) in particular, has been considered as one of crucial barriers to achieving a fast surface oxygen exchange rate of perovskite oxide electrodes for solid oxide fuel cells (SOFCs). However, the major driving force for the segregation phenomenon still remains unknown, and thus it is also unknown how to maximize the cathode performance. In this work, we fabricated epitaxial thin films of SrTi1-xFexO3-δ (STF) via pulsed laser deposition (PLD) and quantitatively characterized their microstructures, surface chemical compositions and oxygen exchange rates by a range of analysis tools, in this case HR-TEM, HR-XRD, angle resolved X-ray photoelectron spectroscopy (AR-XPS) and electrical conductivity relaxation (ECR). The use of well-defined epitaxial thin films not only guarantees high precision, reproducibility and reliability of the surface properties, but also enables us to control the degree of misfit strain by varying the choice of the substrate and the target composition. This, in combination with density functional theory (DTF) simulation, enabled to reveal a close relationship between the degree of surface Sr segregation and the misfit strain and thereby to identify the governing factors for the Sr segregation phenomenon

Early bone healing around implant surfaces treated with variations in the resorbable blasting media method. A study in rabbits

Objective: this study aimed to histomorphologically and histomorphometrically evaluate the in vivo response to three variations in the resorbable blasting media (RBM) surface processing in a rabbit femur model. Study Design: screw root form implants with 3.75 mm in diameter by 8 mm in length presenting four surfaces (n=8 each): alumina-blasted/acid-etched (AB/AE), bioresorbable ceramic blasted (TCP), TCP + acid etching, and AB/AE + TCP were characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The implants were placed at the distal femur of 8 New Zeland rabbits, remaining for 2 weeks in vivo. After sacrifice, the implants were nondecalcified processed to 30 micro m thickness slides for histomorphology and bone-to-implant contact (BIC) determination. Statistical analysis was performed by one-way ANOVA at 95% level of significance considering implant surface as the independent variable and BIC as the dependent variable. Results: SEM and AFM showed that all surfaces presented rough textures and that calciu-hosohate particles were observed at the TCP group surface. Histologic evaluation showed intimate interaction between newly formed woven bone and all implant surfaces, demonstrating that all surfaces were biocompatible and osseoconductive. Significant differences in BIC were observed between the AB/AE and the AB/AE + TCP, and intermediate values observed for the TCP and TCP + Acid surfaces. Conclusion: irrespective of RBM processing variation, all surfaces were osseoconductive and biocaompatible. The differences in BIC between groups warrant further bone-implant interface biomechanical characterization

Correlation between thermal annealing temperature and Joule-heating based insulator-metal transition in VO2 nanobeams

Rapid thermal annealing of VO2 nanobeams in an ambient argon environment has been carried out at various temperatures after device fabrication. Our analysis revealed that increasing the annealing temperature from 200??C to 400??C results in the reduction of both ohmic and nanobeam resistances with an appreciable decrease in joule-heating based transition voltage and transition temperature, while samples annealed at 500??C exhibited a conducting rutile-phase like characteristics at room temperature. In addition, these variation trends were explored using a physical model and the results were found to be in agreement with the observed results, thus verifying the model.open2

Strabismus and Poor Stereoacuity Associated with Kabuki Syndrome

Kabuki syndrome is characterized by long palpebral fissures, large ears, a depressed nasal tip, and skeletal anomalies associated with postnatal dwarfism and mental retardation. There have been few prior detailed descriptions of strabismus or stereopsis in these patients. We report a patient with Kabuki syndrome who showed small-angle strabismus and poor stereopsis. This case illustrates the need for patients with a diagnosis of Kabuki syndrome to have an ophthalmologic evaluation. Strabismus associated with Kabuki syndrome may have a small angle that can be easily overlooked