808 research outputs found
The time has come to look for metabolic dysfunction-associated fatty liver disease in adult patients with type 1 Gaucher disease
MAFLD is highly prevalent in Gaucher type 1 adult patients as well as in the general population and may worsen liver disease progression. Hepatic complications should be followed up. A healthy lifestyle and therapies of cardiometabolic risk factors should be recommended in Gaucher disease patients
Treatment of nonalcoholic steatohepatitis in adults: present and future
Nonalcoholic steatohepatitis has become one of the most common liver-related health problems. This condition has been linked to an unhealthy diet and weight gain, but it can also be observed in nonobese people. The standard of care is represented by the lifestyle intervention. However, because this approach has several limitations, such as a lack of compliance, the use of many drugs has been proposed. The first-line pharmacological choices are vitamin E and pioglitazone, both showing a positive effect on transaminases, fat accumulation, and inflammation. Nevertheless, vitamin E has no proven effect on fibrosis and on long-term morbidity and mortality and pioglitazone has a negative impact on weight. Other drugs have been studied such as metformin, ursodeoxycholic acid, statins, pentoxiphylline, and orlistat with only partially positive results. Among the emerging treatments, telmisartan is particularly interesting as it seems to have an impact on insulin resistance, liver steatosis, inflammation, and fibrosis. However, the pathogenesis of steatohepatitis is highly complex and is determined by different parallel hits; indeed, the association of different drugs that act on various levels has been suggested. In conclusion, lifestyle intervention should be optimised and the associations of different drugs should be tested in large studies with long-term outcomes
Superconducting gap anisotropy of LuNi2B2C thin films from microwave surface impedance measurements
Surface impedance measurements of LuNi2B2C superconducting thin films as a
function of temperature have been performed down to 1.5 K and at 20 GHz using a
dielectric resonator technique. The magnetic penetration depth closely
reproduces the standard B.C.S. result, but with a reduced value of the energy
gap at low temperature. These data provide evidence for an anisotropic s-wave
character of the order parameter symmetry in LuNi2B2C. From the evaluation of
the real part of complex conductivity, we have observed constructive (type II)
coherence effects in the electromagnetic absorption below Tc.Comment: 15 pages, 4 figure
Mode Confinement in Photonic Quasi-Crystal Point-Defect Cavities for Particle Accelerators
In this Letter, we present a study of the confinement properties of
point-defect resonators in finite-size photonic-bandgap structures composed of
aperiodic arrangements of dielectric rods, with special emphasis on their use
for the design of cavities for particle accelerators. Specifically, for
representative geometries, we study the properties of the fundamental mode (as
a function of the filling fraction, structure size, and losses) via 2-D and 3-D
full-wave numerical simulations, as well as microwave measurements at room
temperature. Results indicate that, for reduced-size structures, aperiodic
geometries exhibit superior confinement properties by comparison with periodic
ones.Comment: 4 pages, 4 figures, accepted for publication in Applied Physics
Letter
Superlensing properties of one-dimensional dielectric photonic crystals
We present the experimental observation of the superlensing effect in a slab
of a one-dimensional photonic crystal made of tilted dielectric elements. We
show that this flat lens can achieve subwavelength resolution in different
frequency bands. We also demonstrate that the introduction of a proper
corrugation on the lens surface can dramatically improve both the transmission
and the resolution of the imaged signal.Comment: 9 pages, 9 figure
Comment: Superconducting transition in Nb nanowires fabricated using focused ion beam
In a recent paper Tettamanzi et al (2009 Nanotechnology \bf{20} 465302)
describe the fabrication of superconducting Nb nanowires using a focused ion
beam. They interpret their conductivity data in the framework of thermal and
quantum phase slips below . In the following we will argue that their
analysis is inappropriate and incomplete, leading to contradictory results.
Instead, we propose an interpretation of the data within a SN proximity model.Comment: 3 pages, 1 figure accepted in Nanotechnolog
Hybrid photonic-bandgap accelerating cavities
In a recent investigation, we studied two-dimensional point-defected photonic
bandgap cavities composed of dielectric rods arranged according to various
representative periodic and aperiodic lattices, with special emphasis on
possible applications to particle acceleration (along the longitudinal axis).
In this paper, we present a new study aimed at highlighting the possible
advantages of using hybrid structures based on the above dielectric
configurations, but featuring metallic rods in the outermost regions, for the
design of extremely-high quality factor, bandgap-based, accelerating
resonators. In this framework, we consider diverse configurations, with
different (periodic and aperiodic) lattice geometries, sizes, and
dielectric/metal fractions. Moreover, we also explore possible improvements
attainable via the use of superconducting plates to confine the electromagnetic
field in the longitudinal direction. Results from our comparative studies,
based on numerical full-wave simulations backed by experimental validations (at
room and cryogenic temperatures) in the microwave region, identify the
candidate parametric configurations capable of yielding the highest quality
factor.Comment: 13 pages, 5 figures, 3 tables. One figure and one reference added;
minor changes in the tex
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