Cumulative radiation exposure during thoracic endovascular aneurysm repair and subsequent follow-up

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Attosecond spectroscopy of bio-chemically relevant molecules

Understanding the role of the electron dynamics in the photochemistry of bio-chemically relevant molecules is key to getting access to the fundamental physical processes leading to damage, mutation and, more generally, to the alteration of the final biological functions. Sudden ionization of a large molecule has been proven to activate a sub-femtosecond charge flow throughout the molecular backbone, purely guided by electronic coherences, which could ultimately affect the photochemical response of the molecule at later times. We can follow this ultrafast charge flow in real time by exploiting the extreme time resolution provided by attosecond light sources. In this work recent advances in attosecond molecular physics are presented with particular focus on the investigation of bio-relevant molecules

TLR Activation Pathways in HIV-1-Exposed Seronegative Individuals

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Trans-Iliac Aortic Valve Replacement: Feasibility, Safety, and Medium-Term Follow-up

BACKGROUND: Transcatheter aortic valve replacement (TAVR) is nowadays generally accepted as the treatment of choice for high- to intermediate-risk patients with severe aortic stenosis not suitable for the standard surgical replacement. Many vascular accesses have been described for the valve delivery, comprising the common iliac artery as the arterial site of access. METHODS: From September 2008 to June 2014, 440 patients underwent TAVR at our institution. We report a series of 12 patients that have undergone TAVR via a trans-iliac (TI) retroperitoneal surgical approach and also discuss its feasibility, security, and medium-term follow-up. RESULTS: The 30-day survival rate was 92%. Only 1 local vascular access major complication occurred requiring an iliac-femoral bypass grafting with a vascular graft. Two patients experienced transient neurological ischemic attack. At 3-year follow-up, all the 11 patients were alive and well and the echocardiographic evaluation revealed good function of the prosthesis. CONCLUSIONS: The TI route seems to be feasible with a low profile of local complications. It may be a reasonable access alternative to the femoral artery and to the trans-apical approach. A broader, prospective study is advisable to gain general consensus on this approach

Forcing Seasonality of influenza-like epidemics with daily Solar resonance

Seasonality of acute viral respiratory diseases is a well-known and yet not fully understood phenomenon. Several models have been proposed to explain the regularity of yearly recurring outbreaks and the phase-differences observed at different latitudes on Earth. Such models take into account known internal causes, primarily the periodic emergence of new virus variants that evade the host immune response. Yet, this alone, is generally unable to explain the regularity of recurrences and the observed phase-differences. Here we show that seasonality of viral respiratory diseases, as well as its distribution with latitude on Earth, can be fully explained by the virucidal properties of UV-B and A Solar photons through a daily, minute-scale, resonant forcing mechanism. Such an induced periodicity can last, virtually unperturbed, from tens to hundreds of cycles, and even in presence of internal dynamics (host's loss of immunity) much slower than seasonal will, on a long period, generate seasonal oscillations.Comment: Accepted for publication by iScience. This version has been modified according to referee's comments. Models for the SARS-CoV-2 epidemic have been updated to model the Italian data from 24 February 2020 through 21 August 202

Solar UV−-B//A radiation is highly effective in inactivating SARS−-CoV−-2

Solar UV$-$C photons do not reach Earth's surface, but are known to be endowed with germicidal properties that are also effective on viruses. The effect of softer UV$-$B and UV$-$A photons, which copiously reach the Earth's surface, on viruses are instead little studied, particularly on single$-$stranded RNA viruses. Here we combine our measurements of the action spectrum of Covid$-$19 in response to UV light, Solar irradiation measurements on Earth during the SARS$-$CoV$-$2 pandemics, worldwide recorded Covid$-$19 mortality data and our 'Solar$-$Pump' diffusive model of epidemics to show that (a) UV$-$B$/$A photons have a powerful virucidal effect on the single$-$stranded RNA virus Covid$-$19 and that (b) the Solar radiation that reaches temperate regions of the Earth at noon during summers, is sufficient to inactivate 63\perc of virions in open$-$space concentrations (1.5 x 103 TCID50$/$mL, higher than typical aerosol) in less than 2 min. We conclude that the characteristic seasonality imprint displayed world$-$wide by the SARS$-$Cov$-$2 mortality time$-$series throughout the diffusion of the outbreak (with temperate regions showing clear seasonal trends and equatorial regions suffering, on average, a systematically lower mortality), might have been efficiently set by the different intensity of UV$-$B$/$A Solar radiation hitting different Earth's locations at different times of the year. Our results suggest that Solar UV$-$B$/$A play an important role in planning strategies of confinement of the epidemics, which should be worked out and set up during spring$/$summer months and fully implemented during low$-$solar$-$irradiation periods.Comment: 11 pages + 3 pages supplementary informatio

Ultraviolet supercontinuum generation using a differentially-pumped integrated glass chip

We investigate the generation of ultrabroadband femtosecond ultraviolet (UV) radiation via third-order harmonic generation in highly confined gas media. A dual-stage differential-pumping scheme integrated into a glass microfluidic chip provides an exceptional gas confinement up to several bar and allows the apparatus to be operated under high-vacuum environment. UV pulses are generated both in argon and neon with up to ∼0.8 μJ energy and 0.2% conversion efficiency for spectra that cover the UVB and UVC regions between 200 and 325 nm. Numerical simulations based on the unidirectional pulse propagation equation reveal that ionization plays a critical role for extending the spectral bandwidth of the generated third-harmonic pulse beyond the tripled 800 nm driving laser pulse bandwidth. By delivering UV supercontinua supporting Fourier transform limits below 2 fs, as well as comparable pulse energies with respect to capillary-based techniques that typically provide high spectral tunability but produce narrower bandwidths, our compact device makes a step forward towards the production and application of sub-fs UV pulses for the investigation of electron dynamics in neutral molecules

Thymic volume predicts long-term immune reconstitution in HIV-infected children treated with highly active antiretroviral therapy

Highly active antiretroviral therapy (HAART) suppresses viral replication and augments CD4 T cell counts. HAART-associated immune restoration is often difficult to predict. We verified whether increases in CD4 cells, and particularly in cells of the naive phenotype, would be associated in HAART-treated children with thymic volume. Long-term immune reconstitution is significantly better in children with bigger thymuses at the initiation of HAART. Thymic volume has a strong predictive value for the immunological effect of HAART