3,263 research outputs found
Fingerprints of Multiple Electron Scatterings in Single-Layer Graphene
The electrons in graphene exhibit unusual behaviours, which can be described by massless Dirac quasiparticles. Understanding electron scattering in graphene has been of significant importance for its future application in electronic devices because electron scattering determines electrical properties such as resistivity and electron transport. There are two types of electron scatterings in graphene: intervalley scattering and intravalley scattering. In single-layer graphene, to date, it has been difficult to observe intravalley scattering because of the suppression of backscattering resulting from the chiral nature of the electrons in graphene. Here, we report the multiple electron scattering behaviours in single-layer graphene on a metallic substrate. By applying one- and two-dimensional Fourier transforms to maps of the local density of states, we can distinguish individual scattering processes from complex interference patterns. These techniques enable us to provide direct evidence of intravalley scattering, revealing a linear dispersion relation with a Fermi velocity of ???7.4 ?? 105 m/s.open
The cap-snatching SFTSV endonuclease domain is an antiviral target
Severe fever with thrombocytopenia syndrome virus (SFTSV) is a tick-borne virus with 12%-30% case mortality rates and is related to the Heartland virus (HRTV) identified in the United States. Together, SFTSV and HRTV are emerging segmented, negative-sense RNA viral (sNSV) pathogens with potential global health impact. Here, we characterize the amino-terminal cap-snatching endonuclease domain of SFTSV polymerase (L) and solve a 2.4-Å X-ray crystal structure. While the overall structure is similar to those of other cap-snatching sNSV endonucleases, differences near the C terminus of the SFTSV endonuclease suggest divergence in regulation. Influenza virus endonuclease inhibitors, including the US Food and Drug Administration (FDA) approved Baloxavir (BXA), inhibit the endonuclease activity in in vitro enzymatic assays and in cell-based studies. BXA displays potent activity with a half maximal inhibitory concentration (I
Substitution for Cu in the electron-doped infinite-layer superconductor Sr0.9La0.1CuO2, Ni reduces Tc much faster than Zn
We report on the effect of substitution for Cu on Tc of electron-doped
infinite-layer superconductors Sr0.9La0.1Cu1-xRxO2, R = Zn and Ni. We found
that Tc was nearly constant until x = 0.03 for R = Zn, while superconductivity
was nearly suppressed for x = 0.02 with dTc/dx = 20 K/% for R = Ni. This
behavior is very similar to that of conventional superconductors. These
findings are discussed in terms of the superconducting gap symmetry in the
cuprate superconductors including another electron-doped superconductor,
(Nd,Ce)2CuO4-y.Comment: 5 pages and 2 EPS figures, [email protected] for material reques
A Novel Inhibitory Mechanism of Mitochondrion-Dependent Apoptosis by a Herpesviral Protein
Upon viral infection, cells undergo apoptosis as a defense against viral replication. Viruses, in turn, have evolved elaborate mechanisms to subvert apoptotic processes. Here, we report that a novel viral mitochondrial anti-apoptotic protein (vMAP) of murine γ-herpesvirus 68 (γHV-68) interacts with Bcl-2 and voltage-dependent anion channel 1 (VDAC1) in a genetically separable manner. The N-terminal region of vMAP interacted with Bcl-2, and this interaction markedly increased not only Bcl-2 recruitment to mitochondria but also its avidity for BH3-only pro-apoptotic proteins, thereby suppressing Bax mitochondrial translocation and activation. In addition, the central and C-terminal hydrophobic regions of vMAP interacted with VDAC1. Consequently, these interactions resulted in the effective inhibition of cytochrome c release, leading to the comprehensive inhibition of mitochondrion-mediated apoptosis. Finally, vMAP gene was required for efficient γHV-68 lytic replication in normal cells, but not in mitochondrial apoptosis-deficient cells. These results demonstrate that γHV-68 vMAP independently targets two important regulators of mitochondrial apoptosis-mediated intracellular innate immunity, allowing efficient viral lytic replication
OGLE-2015-BLG-0051/KMT-2015-BLG-0048Lb: a Giant Planet Orbiting a Low-mass Bulge Star Discovered by High-cadence Microlensing Surveys
We report the discovery of an extrasolar planet detected from the combined
data of a microlensing event OGLE-2015-BLG-0051/KMT-2015-BLG-0048 acquired by
two microlensing surveys. Despite that the short planetary signal occurred in
the very early Bulge season during which the lensing event could be seen for
just about an hour, the signal was continuously and densely covered. From the
Bayesian analysis using models of the mass function, matter and velocity
distributions combined with the information of the angular Einstein radius, it
is found that the host of the planet is located in the Galactic bulge. The
planet has a mass and it is orbiting a
low-mass M-dwarf host with a projected separation AU.
The discovery of the planet demonstrates the capability of the current
high-cadence microlensing lensing surveys in detecting and characterizing
planets.Comment: 7 pages, 6 figure
Removal of Kidney Stones by Extracorporeal Shock Wave Lithotripsy Is Associated with Delayed Progression of Chronic Kidney Disease
∙ The authors have no financial conflicts of interest. © Copyright: Yonsei University College of Medicine 2012 This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial Licens
Space-based Microlens Parallax Observation As a Way to Resolve the Severe Degeneracy between Microlens-parallax and Lens-orbital Effect
In this paper, we demonstrate the severity of the degeneracy between the
microlens-parallax and lens-orbital effects by presenting the analysis of the
gravitational binary-lens event OGLE-2015-BLG-0768. Despite the obvious
deviation from the model based on the the linear observer motion and the static
binary, it is found that the residual can be almost equally well explained by
either the parallactic motion of the Earth or the rotation of the binary lens
axis, resulting in the severe degeneracy between the two effects. We show that
the degeneracy can be readily resolved with the additional data provided by
space-based microlens parallax observations. Enabling to distinguish between
the two higher-order effects, space-based microlens parallax observations will
make it possible not only to accurately determine the physical lens parameters
but also to further constrain the orbital parameters of binary lenses.Comment: 6 pages, 5 figure
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