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Nanomaterials offer many unique opportunities for the development of effective and rapid point-of-care (POC) devices to be exploited in many fields, including early diagnosis, health monitoring, and pollutant detection. In particular, gold nanoparticles (AuNPs) exhibit tunable catalytic and plasmonic properties, which are key enabling tools to design and develop innovative detection schemes in several sensing applications. The aim of this PhD project was the development of AuNPs-based colorimetric POCs to detect heavy metal ion contaminations and specific biomarkers in non-invasive biological fluids. First, we developed a novel strategy that exploits the combination of the plasmonic and catalytic properties of AuNPs to achieve an ultrafast (1 min) and sensitive colorimetric sensor for highly toxic methyl mercury. Taking advantage of the AuNP nanocatalyst to promote the rapid reduction of methyl mercury with nucleation on the particle surface and consequent aggregation-induced plasmonic shift, we were able to detect by naked-eye mercury contaminations as low as 20 ppb, which is relevant for food contaminations or biological fluid assessment. Moreover, an innovative and versatile platform, based on multibranched AuNPs, was developed for the detection of salivary biomarkers. Coupling etching and growing reactions in a reshaping process onto the nanostars surface, we created a customizable platform with boosted color change readout for fast detection of salivary glucose at low concentrations. The nanosensor performance was validated on samples from patients with diabetes, proving its potential as a novel non-invasive tool for frequent monitoring of glycaemia. As side project we also investigated the platinum nanoparticles enzymatic activity in a colorimetric sensor for inorganic mercury contamination monitoring in water sources.

HD3167 is a bright (V = 8.9 mag) K0V star observed by the NASA's K2 space mission during its Campaign 8. It has been recently found to host two small transiting planets, namely, HD 3167b, an ultra short period (0.96 days) super-Earth, and HD 3167c, a mini-Neptune on a relatively long-period orbit (29.85 d). Here we present an intensive radial velocity follow-up of HD 3167 performed with the FIES@NOT, HARPS@ESO-3.6m, and HARPS-N@TNG spectrographs. We revise the system parameters and determine radii, masses, and densities of the two transiting planets by combining the K2 photometry with our spectroscopic data. With a mass of 5.69 +/- -0.44 M-circle plus, radius of 1.574 +/- -0.054 R-circle plus, and mean density of 8.00(-0.98)(+1.0) g/cm(-3), HD 3167b joins the small group of ultra-short period planets known to have a rocky terrestrial composition. HD 3167c has a mass of 8.33(-1.85)(+1.79) M-circle plus and a radius of 2.740(-0.100)(+0.106) R-circle plus, yielding a mean density of 2.21(-0.53)(+0.56) g/cm(-3), indicative of a planet with a composition comprising a solid core surrounded by a thick atmospheric envelope. The rather large pressure scale height (similar to 350 km) and the brightness of the host star make HD 3167c an ideal target for atmospheric characterization via transmission spectroscopy across a broad range of wavelengths. We found evidence of additional signals in the radial velocity measurements but the currently available data set does not allow us to draw any firm conclusion on the origin of the observed variation.

HD3167 is a bright (V=8.9 mag) K0V star observed by the NASA's K2 space mission during its Campaign 8. It has been recently found to host two small transiting planets, namely, HD3167b, an ultra short period (0.96 d) super-Earth, and HD3167c, a mini-Neptune on a relatively long-period orbit (29.85 d). Here we present an intensive radial velocity follow-up of HD3167 performed with the FIES@NOT, HARPS@ESO-3.6m, and HARPS-N@TNG spectrographs. We revise the system parameters and determine radii, masses, and densities of the two transiting planets by combining the K2 photometry with our spectroscopic data. With a mass of 5.69+/-0.44 MEarth, radius of 1.574+/-0.054 REarth, and mean density of 8.00(+1.0)(-0.98) g/cm^3, HD3167b joins the small group of ultra-short period planets known to have a rocky terrestrial composition. HD3167c has a mass of 8.33 (+1.79)(-1.85) MEarth and a radius of 2.740(+0.106)(-0.100) REarth, yielding a mean density of 2.21(+0.56)(-0.53) g/cm^3, indicative of a planet with a composition comprising a solid core surrounded by a thick atmospheric envelope. The rather large pressure scale height (about 350 km) and the brightness of the host star make HD3167c an ideal target for atmospheric characterization via transmission spectroscopy across a broad range of wavelengths. We found evidence of additional signals in the radial velocity measurements but the currently available data set does not allow us to draw any firm conclusion on the origin of the observed variation., Comment: 18 pages, 11 figures, 5 tables

Il contributo presenta e argomenta gli esiti di una fase di un percorso di ricerca-formazione intrapreso con molteplici servizi per l'infanzia. L'analisi mette in evidenza il valore che i testi osservativi possono assumere all'interno di quei servizi nei quali l'agire educativo intenda essere il frutto di un lavoro collettivo di professionalità che riflettono insieme per comprendere i sensi e i significati che si costruiscono con e nelle relazioni educative.

We report the characterization and independant detection of K2-60b, as well as the detection and characterization of EPIC 216468514b, two transiting hot gaseous planets from the K2 space mission. We confirm the planetary nature of the two systems and determine their fundamental parameters combining the K2 time-series data with FIES@NOT and HARPS-N@TNG spectroscopic observations. K2-60b has a radius of 0.683 +/- 0.037 RJup and a mass of 0.426 +/- 0.037 MJup and orbits a G4V star with an orbital period of 3.00267 +/- 0.00006 days. EPIC 216468514b has a radius of 1.44 +/- 0.15RJup and a mass of 0.84 +/- 0.08 MJup and orbits an F9 IV star every 3.31392 +/- 0.00002 days. K2-60b is among the few planets at the edge of the so-called "desert" of short-period sub Jovian planets. EPIC 216468514b is a highly inflated Jovian planet orbiting an evolved star about to leave the main sequence., 10 pages, 10 figures

To date there have been no photographic methods reported for assessing the standing postural alignment in a manner that can be used in large scale populations. The purpose of this study was to describe a photographic, multi-plane postural measurement method in a pilot group of subjects in a school setting. A total of 83 healthy male adolescents, volunteered for the study, were photographed. The mean age was 14.5 ± 0.7 years (range 14 – 16). The mean height was 170.7 ± 3.5 cm, (range 155 – 187), and the mean weight was 63.2 ± 13.9 kg (range 37 – 110). During procedure, subjects stood on a platform, with specific markers placed on landmarks that could be identified photographically. Photography was accomplished from above, below, each side, and front and back. These six photographs permit views to be projected onto the six sides of an ideal parallelepiped enclosing the body. Five angles were calculated and reported to describe the alignments of the head, shoulders, torso, and pelvis. As expected the means of each of the five angles were small, the absolute value varying from 0 to 7 degrees. This paper describes the results of a simple, practical, and effective way to gather data concerning standing postural alignment in adolescents using a photographic technique. This technique will be used to form a normative database by large-scale studies. Using this approach, a number of angles can be calculated and eventually models can be developed, relating these angles to sitting posture measurements and to symptoms., Italian Journal of Anatomy and Embryology, Vol 119, No 3 (2014)

The open clusters (OC) are gravitationally bound systems of a few tens or hundreds of stars. In our Galaxy, the Milky Way, we know about 3000 open clusters, of very different ages in the range of a few millions years to about 9 Gyr. OCs are mainly located in the Galactic thin disc, with distances from the Galactic centre in the range 4-22 kpc and a height scale on the disc of about 200 pc. Their chemical properties trace those of the environment in which they formed and the metallicity is in the range -0.5

Summary: PHACE syndrome is a neurocutaneous syndrome with the following features: posterior fossa malformations of the brain, large facial hemangiomas, arterial anomalies, cardiac anomalies and aortic coarctation, and eye abnormalities. We report a rare case of bilateral internal carotid artery agenesis with transcranial collaterals from the external carotid arteries and agenesis of the vertebrobasilar system in a possible PHACE syndrome. We suggest that the patient had an incomplete phenotypic expression of the PHACE syndrome. Although the phenotypic spectrum is broad and is still largely unexplored, the extent of the cephalic neural crest cells insulted genetically or by other causes at a certain time during the development of the embryo might explain the variable phenotypic expression of PHACE syndrome.

Defence date: 6 March 2000 Examining board: Prof. Colin Crouch (EUI - Co-supervisor) ; Prof. Klaus Eder (EUI - Supervisor) ; Prof. Marteen A. Hajer (University of Amsterdam) ; Prof. Rudolf Lewanski (Università di Bologna) PDF of thesis uploaded from the Library digitised archive of EUI PhD theses completed between 2013 and 2017

Digitised version produced by the EUI Library and made available online in 2020.

Digitised version produced by the EUI Library and made available online in 2020.

Rup147 is the closest old open cluster, with a distance of less than 300 pc and an age of about 2.5Gyr. It is therefore well suited for testing stellar evolution models and for obtaining precise and detailed chemical abundance information. We combined photometric and astrometric information coming from literature and the Gaia mission with very high-resolution optical spectra of stars in different evolutionary stages to derive the cluster distance, age, and detailed chemical composition. We obtained spectra of six red giants using HARPS-N at the TNG. We also used ESO archive spectra of 22 main sequence stars, observed with HARPS at the 3.6m telescope. The very high resolution (115000) and the large wavelength coverage (about 380-680nm) of the twin instruments permitted us to derive atmospheric parameters, metallicity, and detailed chemical abundances of 23 species from all nucleosynthetic channels. We employed both equivalent widths and spectrum synthesis. We also re-derived the cluster distance and age using Gaia parallaxes, proper motions, and photometry in conjunction with the PARSEC stellar evolutionary models. We fully analysed those stars with radial velocity and proper motion/parallax in agreement with the cluster mean values. We also discarded one binary not previously recognised, and six stars near the MS turn-off because of their high rotation velocity. Our final sample consists of 21 stars (six giants and 15 MS stars). We measured metallicity (the cluster average [Fe/H] is +0.08, rms=0.07) and abundances of light, {\alpha}, Fe-peak, and neutron-capture elements. The Li abundance follows the expectations, showing a tight relation between temperature and abundance on the MS, at variance with M67, and we did not detect any Li-rich giant. We confirm that Rup147 is the oldest nearby open cluster. This makes it very valuable to test detailed features of stellar evolutionary models., Comment: 16 pages including 9 tables. 7 figures. Accepted by A&A