14,959 research outputs found
Far-infrared measurements of oxygen-doped polycrystalline La2CuO4.0315 superconductor under slow-cooled and fast-cooled conditions
We have studied the far-infrared (far-IR) charge dynamics of an equilibrated
pure oxygen doped La2CuO4+0.0315 under slow-cooled and fast-cooled conditions.
The superconducting transition temperature (Tc) for the slow-cooled and that
for the fast-cooled processes were respectively found to be close to the two
intrinsic Tc's: One at 30 K and the other at 15 K. Direct comparison with our
previous results and other far-IR and Raman studies on single crystalline
La2-xSrxCuO4, we conclude that the topology of the pristine electronic phases
that are responsible for the two intrinsic Tc's is holes arranged into
two-dimensional (2D) square lattices.Comment: Submitted to PR
Investigation of nonlinear interaction phenomena in the ionosphere
Ionospheric phenomena as thermal radiation noise, propagation of naturally occurring radio noise through ionosphere, and generation of very low frequency emission
Electronic and magnetic properties of the kagome systems YBaCo4O7 and YBaCo3MO7 (M=Al, Fe)
We present a combined experimental and theoretical x-ray absorption
spectroscopy (XAS) study of the new class of cobaltates YBaCo4O7 and YBaCo3MO7
(M= Al, Fe). The focus is on the local electronic and magnetic properties of
the transition metal ions in these geometrically frustrated kagome compounds.
For the mixed valence cobaltate YBaCo4O7, both the Co2+ and Co3+ are found to
be in the high spin state. The stability of these high spin states in
tetrahedral coordination is compared with those in the more studied case of
octahedral coordination. For the new compound YBaCo3FeO7, we find exclusively
Co2+ and Fe3+ as charge states
Exploiting the circuit breaker cancer evolution model in human clear cell renal cell carcinoma
The incessant interactions between susceptible humans and their respective macro/microenvironments registered throughout their lifetime result in the ultimate manifestation of individual cancers. With the average lifespan exceeding 50 years of age in humans since the beginning of 2
Soft x-ray magnetic circular dichroism study on Gd-doped EuO thin films
We report on the growth and characterization of ferromagnetic Gd-doped EuO
thin films. We prepared samples with Gd concentrations up to 11% by means of
molecular beam epitaxy under distillation conditions, which allows a very
precise control of the doping concentration and oxygen stoichiometry. Using
soft x-ray magnetic circular dichroism at the Eu and Gd M4,5 edges, we found
that the Curie temperature ranged from 69 K for pure stoichiometric EuO to
about 170 K for the film with the optimal Gd doping of around 4%. We also show
that the Gd magnetic moment couples ferromagnetically to that of Eu.Comment: 4 pages, 4 figure
Alternatively activated macrophages promote pancreatic fibrosis in chronic pancreatitis.
Chronic pancreatitis (CP) is a progressive and irreversible inflammatory and fibrotic disease with no cure. Unlike acute pancreatitis (AP), we find that alternatively activated macrophages (AAMs) are dominant in mouse and human CP. AAMs are dependent on interleukin (IL)-4 and IL-13 signalling, and we show that mice lacking IL-4Rα, myeloid-specific IL-4Rα and IL-4/IL-13 were less susceptible to pancreatic fibrosis. Furthermore, we demonstrate that mouse and human pancreatic stellate cells (PSCs) are a source of IL-4/IL-13. Notably, we show that pharmacologic inhibition of IL-4/IL-13 in human ex vivo studies as well as in established mouse CP decreases pancreatic AAMs and fibrosis. We identify a critical role for macrophages in pancreatic fibrosis and in turn PSCs as important inducers of macrophage-alternative activation. Our study challenges and identifies pathways involved in crosstalk between macrophages and PSCs that can be targeted to reverse or halt pancreatic fibrosis progression
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