Search results for "Beni culturali"
showing 10 items of 1017 documents
Inactivation and polymerization of human neuroserpin
2010
Neuroserpin is an inhibitory enzyme, belonging to the family of serpins and involved in several pathologies, such as ischemia, Alzheimer disease, and FENIB (Familial Encephalopathy with Neuroserpin Inclusion Body). Here, we study the mechanism of neuroserpin inactivation and polymerization by different experimental techniques (static and dynamic light scattering, liquid chromatography, Fourier transform infrared spectroscopy, emission spectroscopy). Our results show that at intermediate temperatures (45-55 °C) neuroserpin forms flexible polymers with a size from a few tens to a few hundreds of nanometers. At high temperatures, above 80 °C, our results reveal a different polymeric form, reac…
Functional and dysfunctional isoforms of human neuroserpin
2015
Neuroserpin (NS) is a serine protease inhibitor (SERPIN) involved in different neurological pathologies, including the Familial Encephalopathy with Neuroserpin Inclusion Bodies (FENIB), related to the aberrant polymerization of NS mutants. Here we present an in vitro and in silico characterization of native NS and its dysfunctional conformation isoforms: the proteolytically cleaved conformer, the inactive latent conformer, and the polymeric conformer. Using circular dichroism and fluorescence spectroscopy, we present an experimental validation of the latent model and highlight the main structural features of the different conformers. In par- ticular, emission spectra of aromatic residues yi…
Testing e validazione comparativa di coating idrofobizzanti per superfici in gelcoat
2021
Nell’industria delle telecomunicazioni a supporto del settore aerospaziale, il mantenimento dell’efficacia e della sicurezza delle trasmissioni in condizioni ambientali estreme assume un’importanza crescente, in funzione della sempre maggiore diffusione dei siti trasmittenti/riceventi, operativi su scala planetaria. In questa cornice, si richiede che gli elementi a protezione dei dispositivi installati si dimostrino durevoli nel tempo anche quando esposti ad abbondanti precipitazioni, accumuli nevosi continuati o stratificazioni di ghiaccio, e improvvisi shock termici, garantendo nel contempo la fedeltà della trasmissione. Una marcata idrofobicità degli strati esterni delle coperture risult…
Ori e cromie dei marmi rinascimentali di Palazzo Abatellis: indagine non invasiva tramite spettrometria XRF.
2009
Analisi integrata tramite tecniche di indagine non invasive o micro invasive per lo studio dei Beni Culturali
2012
Combined TL and 10B-alanine ESR dosimetry for BNCT
2004
The dosimetric technique described in this paper is based on electron spin resonance (ESR) detectors using an alanine-boric compound acid enriched with 1 0 B, and beryllium oxide thermoluminescent (TL) detectors; with this combined dosimetry, it is possible to discriminate the doses due to thermal neutrons and gamma radiation in a mixed field. Irradiations were carried out inside the thermal column of a TRIGA MARK II water-pool-type research nuclear reactor, also used for Boron Neutron Capture therapy (BNCT) applications, with thermal neutron fluence from 10 9 to 10 1 4 n t h cm - 2 . The ESR dosemeters using the alanine-boron compound indicated ESR signals about 30-fold stronger than those…
EPR/ALANINE PELLETS WITH LOW Gd CONTENT FOR NEUTRON DOSIMETRY
2013
This paper reports on results obtained by electron paramagnetic resonance (EPR) measurements and Monte Carlo (MC) simulation on a blend of alanine added with low content of gadolinium oxide (5 % by weight) to improve the sensitivity to thermal neutron without excessively affecting tissue equivalence. The sensitivity is enhanced by this doping procedure of more an order of magnitude. The results are compared with those obtained with the addition of boric acid (50 % by weight) where boron is in its natural isotopic composition in order to produce low-cost EPR dosemeters. The gadolinium addition influences neutron sensitivity more than the boron addition. The presence of additives does not sub…
Neutron flux and gamma dose measurement in the BNCT irradiation facility at the TRIGA reactor of the University of Pavia
2018
Abstract University of Pavia is equipped with a TRIGA Mark II research nuclear reactor, operating at a maximum steady state power of 250 kW. It has been used for many years to support Boron Neutron Capture Therapy (BNCT) research. An irradiation facility was constructed inside the thermal column of the reactor to produce a sufficient thermal neutron flux with low epithermal and fast neutron components, and low gamma dose. In this irradiation position, the liver of two patients affected by hepatic metastases from colon carcinoma were irradiated after borated drug administration. The facility is currently used for cell cultures and small animal irradiation. Measurements campaigns have been ca…
Study of the response of phenol compounds exposed to thermal neutrons beams for Electron Paramagnetic Resonance dosimetry
2015
Abstract This paper reports the results regarding a new organic compound (IRGANOX ® 1076 phenols) with and without low content (5% by weight) of gadolinium oxide (Gd 2 O 3 ) for Electron Paramagnetic Resonance (EPR) dosimetry of neutron beams. The dependence of EPR signal as function of neutron dose was investigated in the fluence range studied between 10 11 cm −2 to 10 14 cm −2 . We evaluated also the effect of gadolinium on 60 Co gamma photon sensitivity of this organic compound. Our analysis showed that a low concentration of gadolinium oxide (of the order of 5% of the total mass of the dosimeter) can enhance the thermal neutron sensitivity more than 10 times with a small reduction of …
Hydration dependence of myoglobin dynamics studied with elastic neutron scattering, differential scanning calorimetry and broadband dielectric spectr…
2014
In this work we present a thorough investigation of the hydration dependence of myoglobin dynamics. The study is performed on D2O-hydrated protein powders in the hydration range 0<h<0.5 (h≡gr[D2O]/gr[protein]) and in the temperature range 20-300K. The protein equilibrium fluctuations are investigated with Elastic Neutron Scattering using the spectrometer IN13 at ILL (Grenoble), while the relaxations of the protein + hydration water system are investigated with Broadband Dielectric Spectroscopy; finally, Differential Scanning Calorimetry is used to obtain a thermodynamic description of the system. The effect of increasing hydration is to speed up the relaxations of the myoglobin + hydration …