1,484 research outputs found

    Hardware design for H.264 CODEC implementation on FPGA

    Get PDF
    This work is concerned about an H:264 CODEC implementation on FPGA. H.264 is a relative recent video standard whose popularity is fastly increasing during the last years. New alternative algorithms are object of modern researches whose goal is to get a better and better quality in order to impress the public and be more competitive on the market

    Medical Education in Naples, Italy, at the Time of SARS-CoV-2

    Get PDF
    SARS-CoV-2 pandemic dramatically changed our daytime routine. Our university world was deeply affected by this emergency situation and had to guarantee the teaching activity with online lessons and exams. While it is true that even in non-emergency conditions online teching is an integral part of many universities, the same cannot be said for graduation ceremonies. And what about students' clinical practice and research activity? In the present article, we will discuss about the experiences of a final-year medical student and of a young assistant professor of Surgery

    CMB Polarization Systematics, Cosmological Birefringence and the Gravitational Waves Background

    Full text link
    Cosmic Microwave Background experiments must achieve very accurate calibration of their polarization reference frame to avoid biasing the cosmological parameters. In particular, a wrong or inaccurate calibration might mimic the presence of a gravitational wave background, or a signal from cosmological birefringence, a phenomenon characteristic of several non-standard, symmetry breaking theories of electrodynamics that allow for \textit{in vacuo} rotation if the polarization direction of the photon. Noteworthly, several authors have claimed that the BOOMERanG 2003 (B2K) published polarized power spectra of the CMB may hint at cosmological birefringence. Such analyses, however, do not take into account the reported calibration uncertainties of the BOOMERanG focal plane. We develop a formalism to include this effect and apply it to the BOOMERanG dataset, finding a cosmological rotation angle α=−4.3∘±4.1∘\alpha=-4.3^\circ\pm4.1^\circ. We also investigate the expected performances of future space borne experiment, finding that an overall miscalibration larger then 1∘1^\circ for Planck and 0.2∘0.2\circ for EPIC, if not properly taken into account, will produce a bias on the constraints on the cosmological parameters and could misleadingly suggest the presence of a GW background.Comment: 10 pages, 3 figure

    Using CMB data to constrain non-isotropic Planck-scale modifications to Electrodynamics

    Full text link
    We develop a method to constrain non-isotropic features of Cosmic Microwave Background (CMB) polarization, of a type expected to arise in some models describing quantum gravity effects on light propagation. We describe the expected signatures of this kind of anomalous light propagation on CMB photons, showing that it will produce a non-isotropic birefringence effect, i.e. a rotation of the CMB polarization direction whose observed amount depends in a peculiar way on the observation direction. We also show that the sensitivity levels expected for CMB polarization studies by the \emph{Planck} satellite are sufficient for testing these effects if, as assumed in the quantum-gravity literature, their magnitude is set by the minute Planck length.Comment: 18 pages, 4 figures, 2 table

    Donor Simvastatin Treatment Is Safe and Might Improve Outcomes After Liver Transplantation: A Randomized Clinical Trial.

    Get PDF
    BACKGROUND The current curative approaches for ischemia/reperfusion injury on liver transplantation are still under debate for their safety and efficacy in patients with end-stage liver disease. We present the SIMVA statin donor treatment before Liver Transplants study. METHODS SIMVA statin donor treatment before Liver Transplants is a monocentric, double-blind, randomized, prospective tial aiming to compare the safety and efficacy of preoperative brain-dead donors' treatment with the intragastric administration of 80 mg of simvastatin on liver transplant recipient outcomes in a real-life setting. Primary aim was incidence of patient and graft survival at 90 and 180 d post-transplant; secondary end-points were severe complications. RESULTS The trial enrolled 58 adult patients (18-65 y old). The minimum follow-up was 6 mo. No patient or graft was lost at 90 or 180 d in the experimental group (n = 28), whereas patient/graft survival were 93.1% (P = 0.016) and 89.66% (P = 0.080) at 90 d and 86.21% (P = 0.041) and 86.2% (P = 0.041) at 180 d in the control group (n = 29). The percentage of patients with severe complications (Clavien-Dindo ≥IIIb) was higher in the control group, 55.2% versus 25.0% in the experimental group (P = 0.0307). The only significant difference in liver tests was a significantly higher gamma-glutamyl transferase and alkaline phosphatase at 15 d (P = 0.017), (P = 0.015) in the simvastatin group. CONCLUSIONS Donor simvastatin treatment is safe, and may significantly improve early graft and patient survival after liver transplantation, although further research is mandatory

    Hiding in plain sight: observing planet-starspot crossings with the James Webb Space Telescope

    Get PDF
    Transiting exoplanets orbiting active stars frequently occult starspots and faculae on the visible stellar disc. Such occultations are often rejected from spectrophotometric transits, as it is assumed they do not contain relevant information for the study of exoplanet atmopsheres. However, they can provide useful constraints to retrieve the temperature of active features and their effect on transmission spectra. We analyse the capabilities of the James Webb Space Telescope in the determination of the spectra of occulted starspots, despite its lack of optical wavelength instruments on board. Focusing on K and M spectral types, we simulate starspots with different temperatures and in different locations of the stellar disc, and find that starspot temperatures can be determined to within a few hundred kelvins using NIRSpec/Prism and the proposed NIRCam/F150W2++F322W2's broad wavelength capabilities. Our results are particularly promising in the case of K and M dwarfs of magK≤12.5_K \leq 12.5 with large temperature contrasts
    • …
    corecore