4,992 research outputs found
Effects of regression of left ventricular hypertrophy on diastolic function in hypertensive patients
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Physics and application of photon number resolving detectors based on superconducting parallel nanowires
The Parallel Nanowire Detector (PND) is a photon number resolving (PNR)
detector which uses spatial multiplexing on a subwavelength scale to provide a
single electrical output proportional to the photon number. The basic structure
of the PND is the parallel connection of several NbN superconducting nanowires
(100 nm-wide, few nm-thick), folded in a meander pattern. PNDs were fabricated
on 3-4 nm thick NbN films grown on MgO (TS=400C) substrates by reactive
magnetron sputtering in an Ar/N2 gas mixture. The device performance was
characterized in terms of speed and sensitivity. PNDs showed a counting rate of
80 MHz and a pulse duration as low as 660ps full width at half maximum (FWHM).
Building the histograms of the photoresponse peak, no multiplication noise
buildup is observable. Electrical and optical equivalent models of the device
were developed in order to study its working principle, define design
guidelines, and develop an algorithm to estimate the photon number statistics
of an unknown light. In particular, the modeling provides novel insight of the
physical limit to the detection efficiency and to the reset time of these
detectors. The PND significantly outperforms existing PNR detectors in terms of
simplicity, sensitivity, speed, and multiplication noise
High performance NbN nanowire superconducting single photon detectors fabricated on MgO substrates
We demonstrate high-performance nanowire superconducting single photon
detectors (SSPDs) on ultrathin NbN films grown at a temperature compatible with
monolithic integration. NbN films ranging from 150nm to 3nm in thickness were
deposited by dc magnetron sputtering on MgO substrates at 400C. The
superconducting properties of NbN films were optimized studying the effects of
deposition parameters on film properties. SSPDs were fabricated on high quality
NbN films of different thickness (7 to 3nm) deposited under optimal conditions.
Electrical and optical characterizations were performed on the SSPDs. The
highest QE value measured at 4.2K is 20% at 1300nm
Bacteremia in Cardiac Surgery Patients with Heparin-Induced Thrombocytopenia
We have read with great interest the paper "Characterization of hospitalized cardiovascular patients with suspected heparin-induced thrombocytopenia" by Stoll and co-workers [1] and we found it very important with a view to clinical prevention
Coffee as a nutraceutical beverage
In a recent paper we found that coffee consumption was associated with a decreased risk of developing asymptomatic PAD in a selected population of pre-menopausal women (Mattioli, Migaldi, & Farinetti, 2018). Women with high coffee consumption had a good adherence to Mediterranean Diet and high levels of physical activity suggesting a healthier lifestyle, a known factor of prevention of atherosclerosis
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