3,868 research outputs found
Interpolation of the Josephson interaction in highly anisotropic superconductors from a solution of the two dimensional sine-Gordon equation
In this paper we solve numerically the two dimensional elliptic sine-Gordon
equation with appropriate boundary conditions. These boundary conditions are
chosen to correspond to the Josephson interaction between two adjacent pancakes
belonging to the same flux-line in a highly anisotropic superconductor. An
extrapolation is obtained between the regimes of low and high separation of the
pancakes. The resulting formula is a better candidate for use in numerical
simulations than previously derived formulas.Comment: 18 pages, 9 figure
A tale of three kingdoms: Members of the Phylum Nematoda independently acquired the detoxifying enzyme cyanase through horizontal gene transfer from plants and bacteria
Horizontal gene transfer (HGT) has played an important role in the evolution of nematodes. Among candidate genes, cyanase, which is typically found only in plants, bacteria and fungi, is present in more than 35 members of the Phylum Nematoda, but absent from free-living and clade V organisms. Phylogenetic analyses showed that the cyanases of clade I organisms Trichinella spp., Trichuris spp. and Soboliphyme baturini (Subclass: Dorylaimia) represent a well-supported monophyletic clade with plant cyanases. In contrast, all cyanases found within the Subclass Chromadoria which encompasses filarioids, ascaridoids and strongyloids are homologous to those of bacteria. Western blots exhibited typical multimeric forms of the native molecule in protein extracts of Trichinella spiralis muscle larvae, where immunohisto- chemical staining localized the protein to the worm hypodermis and underlying muscle. Recombinant Trichinella cyanase was bioactive where gene transcription profiles support functional activity in vivo. Results suggest that: (1) independent HGT in parasitic nematodes originated from different Kingdoms; (2) cyanase acquired an active role in the biology of extant Trichinella; (3) acquisition occurred more than 400 million years ago (MYA), prior to the divergence of the Trichinellida and Dioctophymatida, and (4) early, free-living ances- tors of the genus Trichinella had an association with terrestrial plants
Localized Charge Transfer Process and Surface Band Bending in Methane Sensing by GaN Nanowires
The physicochemical processes at the surfaces of semiconductor nanostructures
involved in electrochemical and sensing devices are strongly influenced by the
presence of intrinsic or extrinsic defects. To reveal the surface controlled
sensing mechanism, intentional lattice oxygen defects are created on the
surfaces of GaN nanowires for the elucidation of charge transfer process in
methane (CH4) sensing. Experimental and simulation results of electron energy
loss spectroscopy (EELS) studies on oxygen rich GaN nanowires confirmed the
possible presence of 2(ON) and VGa-3ON defect complexes. A global resistive
response for sensor devices of ensemble nanowires and a localized charge
transfer process in single GaN nanowires are studied in situ scanning by Kelvin
probe microscopy (SKPM). A localized charge transfer process, involving the
VGa-3ON defect complex on nanowire surface is attributed in controlling the
global gas sensing behavior of the oxygen rich ensemble GaN nanowires.Comment: 42 pages, 6 figures, Journa
Unique case of central retinal artery occlusion secondary to COVID-19 disease
© 2020 The Authors SARS-COVID-2 has been noted to be associated with neurological symptoms and complications including stroke. Hypercoagulability associated with COVID-19 has been described as a “sepsis-induced coagulopathy” and may predispose to spectrum of thromboembolic events. We present a unique article of isolated central retinal artery occlusion secondary to SARS-COV 2
Conductivity landscape of highly oriented pyrolytic graphite surface containing ribbons and edges
We present an extensive study on electrical spectroscopy of graphene ribbons
and edges of highly oriented pyrolytic graphite (HOPG) using atomic force
microscope (AFM). We have addressed in the present study two main issues, (1)
How does the electrical property of the graphite (graphene) sheet change when
the graphite layer is displaced by shear forces? and (2) How does the
electrical property of the graphite sheet change across a step edge? While
addressing these two issues we observed, (1) variation of conductance among the
graphite ribbons on the surface of HOPG. The top layer always exhibits more
conductance than the lower layers, (2) two different monolayer ribbons on the
same sheet of graphite shows different conductance, (3) certain ribbon/sheet
edges show sharp rise in current, (4) certain ribbons/sheets on the same edge
shows both presence and absense of the sharp rise in the current, (5) some
lower layers at the interface near a step edge shows a strange dip in the
current/conductance (depletion of charge). We discuss possible reasons for such
rich conducting landscape on the surface of graphite.Comment: 13 pages, 9 figures. For better quality figures please contact autho
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