Some Results for a Finite Family of Uniformly -Lipschitzian Mappings in Banach Spaces

The purpose of this paper is to prove a strong convergence theorem for a finite family of uniformly L-Lipschitzian mappings in Banach spaces. The results presented in the paper not only correct some mistakes appeared in the paper by Ofoedu (2006) but also improve and extend some recent results by Chang (2001), Cho et al. (2005), Ofoedu (2006), Schu (1991), and Zeng (2003, 2005)

Single-layer behavior and slow carrier density dynamic of twisted graphene bilayer

We report scanning tunneling microscopy (STM) and spectroscopy (STS) of twisted graphene bilayer on SiC substrate. For twist angle ~ 4.5o the Dirac point ED is located about 0.40 eV below the Fermi level EF due to the electron doping at the graphene/SiC interface. We observed an unexpected result that the local Dirac point around a nanoscaled defect shifts towards the Fermi energy during the STS measurements (with a time scale about 100 seconds). This behavior was attributed to the decoupling between the twisted graphene and the substrate during the measurements, which lowers the carrier density of graphene simultaneously

Electronic Structures of Graphene Layers on Metal Foil: Effect of Point Defects

Here we report a facile method to generate a high density of point defects in graphene on metal foil and show how the point defects affect the electronic structures of graphene layers. Our scanning tunneling microscopy (STM) measurements, complemented by first principle calculations, reveal that the point defects result in both the intervalley and intravalley scattering of graphene. The Fermi velocity is reduced in the vicinity area of the defect due to the enhanced scattering. Additionally, our analysis further points out that periodic point defects can tailor the electronic properties of graphene by introducing a significant bandgap, which opens an avenue towards all-graphene electronics.Comment: 4 figure

Strain Induced One-Dimensional Landau-Level Quantization in Corrugated Graphene

Theoretical research has predicted that ripples of graphene generates effective gauge field on its low energy electronic structure and could lead to zero-energy flat bands, which are the analog of Landau levels in real magnetic fields. Here we demonstrate, using a combination of scanning tunneling microscopy and tight-binding approximation, that the zero-energy Landau levels with vanishing Fermi velocities will form when the effective pseudomagnetic flux per ripple is larger than the flux quantum. Our analysis indicates that the effective gauge field of the ripples results in zero-energy flat bands in one direction but not in another. The Fermi velocities in the perpendicular direction of the ripples are not renormalized at all. The condition to generate the ripples is also discussed according to classical thin-film elasticity theory.Comment: 4 figures, Phys. Rev.

Alpha-fetoprotein level as a biomarker of liver fibrosis status: a cross-sectional study of 619 consecutive patients with chronic hepatitis B

BACKGROUND: Hepatitis B virus (HBV) infection is a serious public health problem worldwide. This study aimed to investigate the relationship between serum alpha-fetoprotein (AFP) levels and pathological stages of liver biopsy in patients with chronic hepatitis B (CHB). METHODS: The study included 619 patients who were diagnosed with CHB from March 2005 to December 2011. AFP levels were measured by electrochemiluminescence. Liver biopsy samples were classified into five levels of inflammation (G) and fibrosis (S) stages, according to the Chinese guidelines for prevention and treatment of viral hepatitis. Two multivariable ordinal regression models were performed to determine associations between AFP, GGT, and APRI (AST/PLT ratio) and stages of inflammation and fibrosis. RESULTS: Significant positive and moderate correlations were shown between AFP levels and inflammation stages and between AFP levels and fibrosis stages (ρ = 0.436 and 0.404, p < 0.001). Median values of AFP at liver fibrosis stages S0-1, S2, S3, and S4 were 3.0, 3.4, 5.4, and 11.3 ng/ml, respectively, and median APRI (AST/PLT ratio) was 0.41. Receiver operating characteristic (ROC) curve analyses revealed that the areas under the curves (AUCs) were 0.685, 0.727, and 0.755 (all p <0.001) for judging inflammation stages of G ≥ 2, G ≥ 3, G = 4 by AFP; and 0.691, 0.717, and 0.718 (all p <0.001) for judging fibrosis stages of S ≥ 2, S ≥ 3, and S = 4 by AFP. APRI levels showed significant positive and moderate correlations with inflammation stages (ρ = 0.445, p < 0.001). AST, GGT, and APRI levels showed significant positive but very weak to weak correlations with fibrosis stages (ρ = 0.137, 0.237, 0.281, p < 0.001). CONCLUSIONS: Serum AFP levels increased as pathological levels of inflammation and fibrosis increased in CHB patients. Our data showed the clinical significance of serum AFP levels in diagnosing liver inflammation and fibrosis. Assessment of liver pathology may be improved by creating a predictive mathematical model by which AFP levels with other biomarkers

Gut microbiota-derived endotoxin enhanced the incidence of cardia bifida during cardiogenesis

Background: Cytotoxicity and inflammation-associated toxic responses could be induced by bacterial lipopolysaccharides (LPS) in vitro and in vivo respectively. However, the mechanism involved in LPS-induced cardiac malformation in prenatal fetus is still unknown. Methods and results: In this study, we demonstrated that LPS was induced in gut microbiota imbalance mice, and next, LPS exposure during gastrulation in the chick embryo increased the incidence of cardia bifida. Gene transfection and tissue transplantation trajectory indicated that LPS exposure restricted the cell migration of cardiac progenitors to primary heart field in gastrula chick embryos. In vitro explant allograft of GFP-labeled anterior primitive streak demonstrated that LPS treatments could inhibit cell migration. A similar observation was also obtained from the cell migration assay of scratch wounds using primary culture of cardiomyocytes or H9c2 cells. In the embryos exposed to LPS, expressions of Nkx2.5 and GATA5 were disturbed. These genes are associated with cardiomyocyte differentiation when heart tube fusion occurs. Furthermore, pHIS3, C-caspase3 immunohistological staining indicated that cell proliferation decreased, cell apoptosis increased in the heart tube of chick embryo. Meanwhile, in vivo, pHIS3 immunohistological staining and Hochest/PI staining also draw the similar conclusions. The LPS exposure also caused the production of excess ROS, which might damage the cardiac precursor cells of developing embryos. At last, we showed that LPS-induced cardia bifida could be partially rescued through the addition of antioxidants. Conclusions: Together, these results reveal that excess ROS generation is involved in the LPS-induced defects in heart tube during chick embryo development. This article is protected by copyright. All rights reserve