Chapter A New Compact VNIR Hyperspectral Imaging System for Non-Invasive Analysis in the FineArt and Architecture Fields

A new compact Specim IQ hyperspectral camera working in the 400-1000 nm range has been launched on the market. Its use in the investigation of different artworks and under diverse environmental conditions will be presented

Creation and characterization of He-related color centers in diamond

Diamond is a promising material for the development of emerging applications in quantum optics, quantum information and quantum sensing. The fabrication and characterization of novel luminescent defects with suitable opto-physical properties is therefore of primary importance for further advances in these research fields. In this work we report on the investigation in the formation of photoluminescent (PL) defects upon MeV He implantation in diamond. Such color centers, previously reported only in electroluminescence and cathodoluminescence regime, exhibited two sharp emission lines at 536.5 nm and 560.5 nm, without significant phonon sidebands. A strong correlation between the PL intensities of the above-mentioned emission lines and the He implantation fluence was found in the 10^15-10^17 cm^{-2} fluence range. The PL emission features were not detected in control samples, i.e. samples that were either unirradiated or irradiated with different ion species (H, C). Moreover, the PL emission lines disappeared in samples that were He-implanted above the graphitization threshold. Therefore, the PL features are attributed to optically active defects in the diamond matrix associated with He impurities. The intensity of the 536.5 nm and 560.5 nm emission lines was investigated as a function of the annealing temperature of the diamond substrate. The emission was observed upon annealing at temperatures higher than 500{\deg}C, at the expenses of the concurrently decreasing neutral-vacancy-related GR1 emission intensity. Therefore, our findings indicate that the luminescence originates from the formation of a stable lattice defect. Finally, the emission was investigated under different laser excitations wavelengths (i.e. 532 nm and 405 nm) with the purpose of gaining a preliminary insight about the position of the related levels in the energy gap of diamond

La salute mentale negli studenti di medicina: il progetto del Servizio di Aiuto Psicologico (SAP) dell’Università degli Studi di Torino

     Dalla letteratura emerge come gli studenti di medicina spesso presentino livelli di ansia, stress e de-pressione superiori alla popolazione generale. Si rende quindi sempre più necessario un supporto psi-cologico gratuito e fruibile interno alle università. La facoltà di Medicina e Chirurgia dell’Università de-gli Studi di Torino può vantare un servizio di aiuto psicologico (SAP) dedicato. Il presente studio ha lo scopo di illustrare in termini sociodemografici, clinici e psicopatologici la coorte di studenti che ha usufruito del servizio. Il progetto prevede un colloquio conoscitivo al termine del quale, se necessario, seguirà una presa in carico dal punto di vista psicologico e/o psichiatrico; agli studenti inoltre viene chiesto di compilare alcuni test psicometrici per valutare depressione, ansia e stress. Da gennaio 2019 ad agosto 2020, 166 studenti hanno fatto richiesta per un primo colloquio. Dal nostro studio emerge come, in linea con la letteratura, una sintomatologia depressiva e/o di tipo ansioso sia presen-te negli utenti. I dati raccolti e altresì il feedback ricevuto dagli studenti dimostrano l’utilità del servi-zio.      Dalla letteratura emerge come gli studenti di medicina spesso presentino livelli di ansia, stress e de-pressione superiori alla popolazione generale. Si rende quindi sempre più necessario un supporto psi-cologico gratuito e fruibile interno alle università. La facoltà di Medicina e Chirurgia dell’Università de-gli Studi di Torino può vantare un servizio di aiuto psicologico (SAP) dedicato. Il presente studio ha lo scopo di illustrare in termini sociodemografici, clinici e psicopatologici la coorte di studenti che ha usufruito del servizio. Il progetto prevede un colloquio conoscitivo al termine del quale, se necessario, seguirà una presa in carico dal punto di vista psicologico e/o psichiatrico; agli studenti inoltre viene chiesto di compilare alcuni test psicometrici per valutare depressione, ansia e stress. Da gennaio 2019 ad agosto 2020, 166 studenti hanno fatto richiesta per un primo colloquio. Dal nostro studio emerge come, in linea con la letteratura, una sintomatologia depressiva e/o di tipo ansioso sia presen-te negli utenti. I dati raccolti e altresì il feedback ricevuto dagli studenti dimostrano l’utilità del servi-zio.&nbsp

Let's Twist Again: N=2 Super Yang Mills Theory Coupled To Matter

We give the twisted version of N=2 Super Yang Mills theory coupled to matter, including quantum fields, supersymmetry transformations, action and algebraic structure. We show that the whole action, coupled to matter, can be written as the variation of a nilpotent operator, modulo field equations. An extended Slavnov-Taylor identity, collecting gauge symmetry and supersymmetry, is written, which allows to define the web of algebraic constraints, in view of the algebraic renormalization and of the extension of the non-renormalization theorems holding for N=2 SYM theory without matter.Comment: 28 pages, final version to be published on CQ

Diamond-based sensors for in vitro cellular radiobiology: Simultaneous detection of cell exocytic activity and ionizing radiation

The investigation of secondary effects induced by ionizing radiation represents a new and ever-growing research field in radiobiology. This new paradigm cannot be investigated only using standard instrumentation and methodologies, but rather requires novel technologies to achieve significant progress. In this framework, we developed diamond-based sensors that allow simultaneous real-time measurements with a high spatial resolution of the secretory activity of a network of cells cultured on the device, as well as of the dose at which they are exposed during irradiation experiments. The devices were functionally characterized by testing both the above-mentioned detection schemes, namely: amperometric measurements of neurotransmitter release from excitable cells (such as dopamine or adrenaline) and dosimetric evaluation using different ionizing particles (alpha particle and X-ray photons). Finally, the sensors were employed to investigate the effects induced by X-rays on the exocytotic activity of PC12 neuroendocrine cells by monitoring the modulation of the dopamine release in real-time

Tailoring the Local Conductivity of TiO 2

It is well known that intense synchrotron beams can alter the state of materials, but this effect is generally considered undesired radiation damage. The effect of local irradiation of TiO2 rutile single crystals is investigated by a 56 × 57 nm2 synchrotron X‐ray nanobeam at 17.4 keV. Aside from a transient increase of conductivity due to a photovoltaic‐like process, a nonvolatile localized change of resistance by about 4 orders of magnitude is measured after X‐ray exposure. This effect can be ascribed to the local generation of oxygen vacancies by the X‐ray nanoprobe, which are subsequently ordered by the electric field applied during the acquisition of I–V curves. These results demonstrate that intense synchrotron beams can create oxygen vacancies in materials with tightly bound oxygen atoms, highlighting that X‐ray nanoprobes could become an effective tool for oxide nanofabrication, able to locally tune the material resistivity. For instance, since the localized presence and migration of oxygen vacancies is an essential requisite for redox‐based memristive devices, the possibility to locally induce oxygen vacancies could represent a novel tool for the production of oxide‐based memristive devices, replacing the problematic electroforming step

Chapter A New Compact VNIR Hyperspectral Imaging System for Non-Invasive Analysis in the FineArt and Architecture Fields

A new compact Specim IQ hyperspectral camera working in the 400-1000 nm range has been launched on the market. Its use in the investigation of different artworks and under diverse environmental conditions will be presented

Modification of the structure of diamond with MeV ion implantation

We present experimental results and numerical simulations to investigate the modification of structural-mechanical properties of ion-implanted single-crystal diamond. A phenomenological model is used to derive an analytical expression for the variation of mass density and elastic properties as a function of damage density in the crystal. These relations are applied together with SRIM Monte Carlo simulations to set up finite element simulations for the determination of internal strains and surface deformation of MeV-ion-implanted diamond samples. The results are validated through comparison with high resolution X-ray diffraction and white-light interferometric profilometry experiments. The former are carried out on 180 key B implanted diamond samples, to determine the induced structural variation, in terms of lattice spacing and disorder, whilst the latter are performed on 1.8 MeV He implanted diamond samples to measure surface swelling. The effect of thermal processing on the evolution of the structural-mechanical properties of damaged diamond is also evaluated by performing the same profilometric measurements after annealing at 1000 degrees C. and modeling the obtained trends with a suitably modified analytical model. The results allow the development of a coherent model describing the effects of MeV-ion-induced damage on the structural-mechanical properties of single-crystal diamond. In particular, we suggest a more reliable method to determine the so-called diamond "graphitization threshold" for the considered implantation type