340 research outputs found
On the hadronic origin of the TeV radiation from GRB 190114C
The recently discovered TeV emission from Gamma-Ray Bursts (GRBs) hints
towards a possible hadronic origin of this radiation component. We developed a
Monte Carlo (MC) simulation reproducing the kinematics of photo-hadronic
interactions at internal shocks, including the pair production process that the
secondary gamma rays undergo in the GRB jet. We find that sub-TeV observations
of GRB 190114C can be reproduced by a baryonic energy content comparable to
that in sub-GeV photons and a bulk Lorentz factor , with a ms
variability timescale. Neutrino flux predictions by the model are found to be
consistent with experimental upper limits set by ANTARES and IceCube
Adaptive mesh refinement versus subgrid friction interpolation in simulations of Antarctic ice dynamics
Geophysical Research Letters
Pseudomonas aeruginosa (PA) resistant to colistin (CL) in Italian cystic fibrosis (CF) patients
Change of the ice rheology with climatic transitions – implication on ice flow modelling and dating of the EPICA Dome C core
International audienceThe study of the distribution of the crystallographic orientations (the fabric) along ice cores supplies information on the past and current ice flows of ice-sheets. Beside the usually observed formation of a vertical single maximum fabric, the EPICA Dome Concordia ice core (EDC) shows an abrupt and unexpected strenghtening of its fabric during termination II around 1750 m depth. Such strengthenings were already observed for sites located on an ice-sheet. This suggests that horizontal shear could occur along the EDC core. Moreover, the change in the fabric leads to a modification of the viscosity between neighbouring ice layers. Through the use of an anisotropic ice flow model, we quantify the change in viscosity and investigate its implication on ice flow and dating
Change in ice rheology during climate variations – implications for ice flow modelling and dating of the EPICA Dome C core
The study of the distribution of crystallographic orientations (i.e., the fabric) along ice cores provides information on past and current ice flow in ice-sheets. Besides the usually observed formation of a vertical single maximum fabric, the EPICA Dome C ice core (EDC) shows an abrupt and unexpected strengthening of its fabric during termination II around 1750 m depth. Such strengthening has already been observed for sites located on an ice-sheet flank. This suggests that horizontal shear could occur along the EDC core. Moreover, the change in the fabric leads to a modification of the effective viscosity between neighbouring ice layers. Through the use of an anisotropic ice flow model, we quantify the change in effective viscosity and investigate its implication for ice flow and dating
Mesenchymal stem cell therapy promotes renal repair by limiting glomerular podocyte and progenitor cell dysfunction in adriamycin-induced nephropathy
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Generalization of the Luttinger Theorem for Fermionic Ladder Systems
We apply a generalized version of the Lieb-Schultz-Mattis Theorem to
fermionic ladder systems to show the existence of a low-lying excited state
(except for some special fillings). This can be regarded as a non-perturbative
proof for the conservation under interaction of the sum of the Fermi wave
vectors of the individual channels, corresponding to a generalized version of
the Luttinger Theorem to fermionic ladder systems. We conclude by noticing that
the Lieb-Schultz-Mattis Theorem is not applicable in this form to show the
existence of low-lying excitations in the limit that the number of legs goes to
infinity, e.g. in the limit of a 2D plane.Comment: RevTex, 4 pages with 4 eps figure
Phases of the two-band model of spinless fermions in one dimension
We study the two-band model of spinless fermions in one dimension for weak
repulsive interactions. In this case, the model is equivalent to the weakly
interacting spinless two-leg ladder. We obtain analytic expressions for the
superconducting pairing correlation function and the charge density correlation
function, which show, that a finite interchain hopping t_p results in dominant
superconductivity for repulsive interactions (for vanishing t_p, we recover
previous results). We furthermore find that the transition from the
superconducting phase to the usual one-dimensional (Luttinger) metal at large
doping occurs via a mixed phase, where superconducting pairs are formed in the
bonding band only. We give the phase diagram as a function of temperature and
doping.Comment: 10 pages, 2 figure
Adding a statin to a combination of ACE inhibitor and ARB normalizes proteinuria in experimental diabetes, which translates into full renoprotection
The capacity of renin-angiotensin system (RAS) inhibitors to delay progression of diabetic nephropathy depends on the time at which therapy is started. A multimodal intervention is required to afford renoprotection in overt diabetic nephropathy. Here we assessed the effects of maximal RAS inhibition by angiotensin-converting enzyme (ACE) inhibitor plus angiotensin II type 1 receptor blocker (ARB) in combination with statin in rats with overt diabetic nephropathy. Uninephrectomized rats made diabetic by streptozotocin were orally treated from 4 (when proteinuria and renal lesions had developed) to 8 mo with vehicle, lisinopril plus candesartan, lisinopril plus candesartan plus rosuvastatin, or rosuvastatin alone. Systolic blood pressure increased in diabetic rats and was significantly lowered by combined therapies. Dual RAS blockade significantly reduced proteinuria compared with vehicle. Addition of statin further lowered proteinuria to control levels. Glomerulosclerosis was ameliorated by RAS inhibitors or statin, and regression was achieved by the addition of statin. Loss of podocytes of diabetic rats was limited by ACE inhibitor plus ARB while normalized by the three drugs. Defective nephrin expression of diabetes was increased by dual RAS blockade or statin and restored by the triple therapy. Tubular damage, interstitial inflammation, and expression of the fibrotic markers transforming growth factor (TGF)-beta 1 and phosphorylated Smad 2/3 in tubuli were significantly reduced by the triple regimen. These data suggest a strategy to target proteinuria to try to achieve regression of renal disease in diabetic patients who do not fully benefit from RAS inhibition alone
Genotypic HIV-1 tropism determination might help to identify people with exhausted treatment options and advanced disease
Objectives: To evaluate HIV-1 tropism in 1382 combined antiretroviral therapy (cART)-experienced patients failing therapy to characterize those with exhausted therapeutic options. Methods: HIV-1 genotypic tropism was inferred through Geno2Pheno by estimating the false-positive-rate (FPR) values. Cumulative resistance and drug activity were evaluated by Stanford algorithm. Results: Overall, median (IQR) CD4 count (cells/mm3) nadir and at last genotypic resistance test (GRT) available were 98 (33-211) and 312 (155-517), respectively. Considering HIV-1 tropism, 30.5% had X4/dual-mixed strains (FPR ≤5%: 22.2%; FPR 5%-10%: 8.3%). By stratifying according to tropism, by decreasing FPR, a significant decrease of CD4 nadir and at last GRT was observed. The proportion of individuals with CD4 count <200 cells/mm3, who were perinatally infected and with a long treatment history significantly increased as FPR levels decreased. Regarding resistance, 933 (67.5%) individuals accumulated at least one class resistance, with 52.7%, 48.2%, 23.5% and 13.2% of individuals showing resistance to NRTIs, NNRTIs, PIs and INIs; while 23.2%, 27.2%, 14.3% and 2.8% harboured resistance to 1, 2, 3 and 4 classes, respectively. Individuals with FPR ≤5% showed a significantly higher level of resistance to PIs, NRTIs and INIs compared with others. The proportion of individuals harbouring strains susceptible to ≤2 active drugs was only about 2%; nonetheless, this proportion doubled (4.6%) in patients infected with FPR ≤5%. Conclusions: Our findings showed that a small proportion of cART failing individuals have limited therapeutic options. However, tropism determination might help to identify people who have accumulated a high level of resistance and have a greater risk of advanced disease
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