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Lead fluoride (PbF2) crystals represent an excellent and relatively innovative choice for high resolution electromagnetic calorimeters with high granularity and fast timing for high intensity environments. For this reason two PbF2 crystals, sized 5× 5 × 40 mm3, were irradiated with 60Co photons up to ∼ 4 Mrad and with 14 MeV neutrons up to a 1013 n/cm2 total fluence. Their loss in transmittance was evaluated at different steps of the photon and neutron irradiation campaign, resulting in a total of 30% loss above 350 nm. With crystals always kept in dark conditions, natural and thermal annealing, as well as optical bleaching with 400 nm light, were performed on the irradiated specimens, resulting in a partial recovery of their original optical characteristics.

A possible anticancer role for somatostatin has been suggested. This study assessed the presence of somatostatin receptor subtype 2A (SSTR2A) in gastric cancer, correlating its expression with histological type, grade, human epidermal growth factor receptor 2 (HER2) expression, and disease outcome.Gastric cancer tissues of 51 consecutive patients were collected for immunohistochemical assessment of both SSTR2A and HER2 expression.SSTR2A expression was observed in 38 (74.5%) cases. Prevalence of SSTR2A expression was significantly higher in well to moderately (G1-2) differentiated gastric cancer as compared to poorly (G3) differentiated tumors (96% vs. 52%; p0.01), as well as in intestinal- than in diffuse-type cancer (97% vs. 20%; p0.001). HER2 expression was positive in 18 (35%) patients, and it was associated with SSTR2A expression (r=0.50, p0.001), being co-expressed in 17 (95%) out of 18 positive cases. RFS was significantly lower in patients with diffuse HER2 expression.This study demonstrated a co-localization between SSTR2A and HER2, potentially opening new therapeutic strategies for patients with gastric cancer.

The deteriorating effect of light on artworks exposed in museums and galleries has been noticed for many years. A number of methods, which act on the illumination source, are presently in use to reduce the damage. A complementary approach is proposed here that consists in blocking the radiation, outside the range of sensitivity of the human eye, before it reaches the artwork. This result can be achieved by an optical coating deposited on the glass pane that is usually put in front of the artworks to protect them from vandalism. In addition to the preservation from illumination induced damage, the proposed coating is also able to improve the observation of the artwork by reducing the reflection effects of uncoated glass. Optical, colorimetric and psychophysical measurements on test samples are reported.

Many optical methods are nowadays in use in the field of art. Most techniques are applied for characterization of materials, monitoring, diagnostics. Optical thin films can find an interesting application for artwork protection from the damage induced by illumination. The deteriorating effect of light on artworks is well known and the conventional approach to reduce the damage consists in lowering the radiation intensity and shortening the exposure duration. A complementary approach is to block all radiations that are not useful for viewing the artwork. A proper optical coating deposited on glass is able to cut the radiation flux at all wavelengths outside the range of sensitivity of the human eye. Glass is already in use in museum and galleries to protect artwork from vandalism and the use of coated glass can result in a simple method for contributing to art conservation. The optical coating will also improve the viewing because of the antireflection effect that can be combined with the protection properties. Particular care must be taken of this aspect because a compromise between conservation rules and visitor satisfaction must be reached. It is important that the thinfilm coating does not introduce color alterations from the point of view of the observer and for this reason color testing on coated glasses must be carried out with real viewers.

First-degree relatives of gastric cancer patients have an increased risk of developing such neoplasia, and several alterations in gastric mucosa of these subjects have been described. On the other hand, both gastric cell hyperproliferation and abnormalities of adhesion molecules have been involved in gastric carcinogenesis. We studied gastric mucosa alterations in first-degree relatives of gastric cancer patients.This prospective, case-controlled study enrolled 39 first-degree relatives of gastric cancer patients and 39 matched controls. Biopsy specimens obtained at endoscopy were used to assess epithelial cell proliferation plus E-cadherin and beta-catenin expression by immunohistochemical methods. H. pylori infection was assessed by histology and a rapid urease test.Gastric epithelial cell proliferation values were not significantly different between the patient and control groups. H. pylori infection significantly increased cell proliferation values both in patients and in controls, without a significant difference between the two groups. Moreover, cell proliferation values were significantly higher in cases harboring intestinal metaplasia than in those without it. Alterations of the adhesion molecules were described exclusively in those patients harboring intestinal metaplasia. In detail, a reduction of both E-cadherin and beta-catenin expression was observed in 8 (67%) out of 12 first-degree relatives and in 6 (67%) out of 9 controls with intestinal metaplasia (p = 0.4). These alterations were similarly distributed between H. pylori infected and uninfected cases.Our data showed that a family history of gastric cancer itself is not associated with gastric cell hyperproliferation. However, both cell hyperproliferation and alterations of adhesion molecules have been detected in those patients with intestinal metaplasia.

Although E-cadherins have been involved in gastric carcinogenesis, their role in precancerous lesions, such as intestinal metaplasia, is still unclear. This study aimed to assess the role of both intestinal metaplasia and H. pylori infection on E-cadherin expression in gastric mucosa.Twenty-one consecutive patients with intestinal metaplasia were enrolled to assess E-cadherin expression in metaplastic areas. Twenty further patients without intestinal metaplasia, with and without H. pylori, were enrolled to evaluate the role of the infection on E-cadherin expression. All patients underwent upper endoscopy and gastric biopsies were taken for histological and immunohistochemical assessment.A substantial reduction of E-cadherin expression in metaplastic areas was observed in 14 (67%) of the 21 patients, similarly in H. pylori-infected and uninfected patients (64% vs 71%, p=0.3). In the group without intestinal metaplasia, no reduction in E-cadherin expression was detected either in infected patients or in those without H. pylori infection.The data showed that intestinal metaplasia is associated with E-cadherin down-regulation, whereas H. pylori infection does not seem to play a direct role in this process.

The ATLAS group of INFN and Roma Tre University is responsible for the test and certification of 60 Barrel Inner Large MDT chambers for the ATLAS muon spectrometer. The gas distribution assembling techniques, the Quality Assurance and Quality Control (QA/QC) tests, the MDT read out and data acquisition at the cosmic ray stand and the standard analysis performed to certify the chambers performance are described. Our man power time estimate for each procedure is also reported. A section is dedicated to the procedures adopted to certify the chambers, together with a proposal for a “Chamber Certification Document” which should be used as a reference document for each assembled, equipped and tested chamber. Finally, a status report of the first 10% Roma Tre QA/QC test is provided.

The chemical reactions and diffusion processe at the interference of a metal with oxides and nitrides are a critical issue in the production of metal-dielectric optical filters. The optical properties of these filters depend on the quality of the interfaces between the metal layer and the adjacent dielectric layers. The chemical and physical processes occuring at the silver-dielectric interface are studied by means of ellipsometry and XPS analysis and comprise the subject of the present work.

The search for efficient, re-absorption-free scintillators has recently focused the attention on antimony-based halides, which exhibit largely Stokes shifted luminescence due to radiative recombination of excitons self-trapped (STE) in strongly Jahn–Teller distorted Sb3+ color centers. Here, the synthesis of a hybrid structure is reported with chemical formula (C13H14N3)3SbCl6 consisting of spatially isolated [SbCl6]3− octahedra separated by organic N,N'-diphenylguanidinium (Gua) molecules. The optical properties of this material are mainly determined by the inorganic component and are characterized by a pronounced Stokes shift of ≈1.3 eV and a room-temperature photoluminescence (PL) efficiency of up to 85%. Remarkably, highly efficient radioluminescence (RL) is observed with scintillation light yields of ≈2000 ph MeV−1 using both soft X-rays and a 124 keV gamma source. Temperature-dependent PL and RL measurements confirm the minor role of non-radiative channels, which are completely suppressed below 100 K. Thermally stimulated luminescence measurements suggest that the traps in Gua3SbCl6 crystals have a significantly large energy depth distribution below the absorbing state.

Radiation detection is of utmost importance in fundamental scientific research, as well as medical diagnostics, homeland security, environmental monitoring and industrial control. Lead halide perovskites (LHPs) are attracting growing attention as high-atomic-number materials for next-generation scintillators and photoconductors for ionizing radiation detection. To unlock their full potential as reliable and cost-effective alternatives to conventional materials, it is necessary for LHPs to conjugate high scintillation yields with emission stability under high doses of ionizing radiation. To date, no definitive solution has been devised to optimize the scintillation efficiency and kinetics of LHPs and nothing is known of their radiation hardness for doses above a few kilograys, to the best of our knowledge. Here we demonstrate that CsPbBr3 nanocrystals exhibit exceptional radiation hardness for γ-radiation doses as high as 1 MGy. Spectroscopic and radiometric experiments highlight that despite their defect tolerance, standard CsPbBr3 nanocrystals suffer from electron trapping in dense surface defects that are eliminated by post-synthesis fluorination. This results in >500% enhancement in scintillation efficiency, which becomes comparable to commercial scintillators, and still retaining exceptional levels of radiation hardness. These results have important implications for the widespread use of LHPs in ultrastable and efficient radiation detectors.

The global need for energy in the world is constantly increasing. Critical fission reactors have proved great efficiency in the energy production, but the fear of nuclear wastes and accidents due to an uncontrolled chain reaction makes these unpleasant to public. More safe fusion reactors, on the opposite, have low efficiency. Hybrid reactors capable of using the advantages of both are studied, but not yet developed. In this paper, a simple fusion–fission pilot experiment model has been developed. A Tokamak with the same characteristics of DTT (Divertor Tokamak Test facility) has been considered as a reference machine for the fusion component. The fusion system has been coupled with a relatively simple low-power fission blanket configured into three different modes by using different fuels and materials. This model could be useful in order to investigate the properties of the fusion–fission hybrid coupling from a neutronic point of view.

The Radial Neutron Camera (RNC) of ITER (International Thermonuclear Experimental Reactor) is a multichannel detection system designed to measure the uncollided neutron flux from the fusion plasma , providing information on the neutron emissivity profiles and source strength. Fission chambers and diamond detectors are candidate detectors for the RNC In-port subsystem. This is a high radiation environment (up to ∼ 5 MGy gamma dose and ∼ 2 × 10 16 n/cm2 neutron fluence) where about 500 baking cycles up to 240 °C are foreseen over the whole ITER lifetime. In order to assess the feasibility of using diamond detectors in such harsh conditions, and to study the best technological solutions, we are currently performing a set of tests to understand the behavior of diamond detectors under radiation and thermal stresses: (1) thermal stress tests at constant temperature of 240 °C and thermal cycling between 100 °C and 240 °C; (2) gamma-hardness test up to a total dose of 4.7 MGy; (3) neutron-hardness test (limited to 2 × 10 14 n/cm2 in this work).

A series of Cu+/Eu3+ co-doped borosilicate glasses have been successfully prepared by melt-quenching method. As proved by transmission spectra, the copper ions are univalent in the investigated borosilicate glasses. Under ultraviolet (UV) excitation at 325 nm, the emission intensity of Eu3+ increased by nearly double due to a large overlapping between the Cu+ and Eu3+ emission peaks. The decreased excitation intensity in UV region and shortened emission lifetime of Cu+ in association with presence of Eu3+ ions consistently suggest an energy transfer process from Cu+ to Eu3+ ions. On the other hand, the partially allowed transition of Cu+ makes contribution to the red emission of Eu3+ at 611 nm in Cu+/Eu3+ co-doped samples, thus shortening the lifetime from the conventional millisecond (∼1.86 ms) to the microsecond (up to around 37 μs) regime. Besides, tunable light is realized by combining the blue-green emission from Cu+ ions with the orange-red one from Eu3+ ions. The light can be continuously tuned by changing the Cu+/Eu3+ concentration ratio, indicating that the present novel Cu+/Eu3+ co-doped borosilicate glasses are potential as fast response and tunable photoluminescence materials.

Conductive and transparent ultra-thin Nickel films are grown by RF sputtering on fused silica substrates. The characteristics of Ni films (thickness, refractive index, and extinction coefficient) are obtained by fitting multi-angle spectrophotometric and ellipsometric data. Films thickness inferred by X ray reflection (XRR) measurements is in good accordance with ellipsometric results. XPS analysis reveals that Ni metal phase is present in the film surface together with Ni mixed oxide phases, which explains the high electrical stability of such films.

The use of proteins as natural biopolymers are sensibly increasing in several application fields such as food industry, packaging and environment protection. In particular, rice proteins (RP) present good nutritional, hypoallergenic and healthful properties very interesting for human consumption. Since ionizing radiation can be successfully applied on protein containing systems involved in different industrial processes, this work aims to determine the effect of gamma radiation on 5 wt%–7.5 wt% RP aqueous solutions in a wide range of absorbed doses up to around 40 kGy. The changes of RP secondary and tertiary structures and their chemical composition were followed by UV–VIS absorbance spectroscopy, luminescence analysis and pH measurements. The experimental data showed the occurrence of the unfolding of RP chains with the increase of the absorbed dose and the formation of new molecules, due to the reaction among tryptophane and tyrosine amino acids and the radical species induced by gamma radiation. The results are also confirmed by the modification of the pH values measured for the irradiated solutions. © 2018 Elsevier Ltd

PLAnetary Transits and Oscillations of stars (PLATO) is a medium sized mission (M3) selected by the European Space Agency (ESA) for launch in 2026. The PLATO payload includes 26 telescopes all based on a six-element refractive optical scheme. Some components will be eventually manufactured by S-FPL51, N-ICZFS11 and S-FTM16 glass whose radiation resistance is partially or totally unknown. The radiation-resistance properties of such materials have been investigated by using a Co-60 gamma-rays source as probe. Each optical component has been characterized by a depth profile curve which describes the transmission loss as a function of the thickness in dependence of the impinging dose. A model to simulate the throughput of the whole instrument has been developed and used to verify the instrument performance considering different stellar spectra. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Ultrathin stable transparent conductive nickel films were deposited on quartz substrates by radio frequency sputtering at room temperature. Such films showed visible transmittance up to 80% and conductivity up to 1.8 × 104 S/cm, further increased to 2,3 × 105 S/cm by incorporation of a micrometric silver grid. Atomic force microscopy and scanning electron microscopy revealed quite compact, smooth and low surface roughness films. Excellent film stability, ease, fast and low cost process fabrication make these films highly competitive compared to indium tin oxide alternative transparent conductors. Films were characterized regarding their morphological, optical and electrical properties. © 2015 Elsevier B.V.

The importance of ground-based measurements of ultraviolet radiation has increased since the discovery of the stratospheric ozone layer depletion. Spectroradiometers are the most widely used class of instruments, although the requirement to work in attended stations is sometimes limiting. In this work we present a filter radiometer, named F-RAD, with good optical stability, very short sampling time (1 min), and proven reliability. The instrument is based on a stand-alone functioning, making it suitable for operation in hostile environments. The total ozone column (TOC) was estimated by the irradiance ratio at wavelengths where the ozone absorbs the solar radiation and where the radiation is not absorbed. Direct correlation between the TOC values estimated by F-RAD and by the Ozone Monitoring Instrument (OMI) was found, and the standard deviations of the ratios between such values were calculated. Three wavelength ratios were identified to take into account the dependence of the measurements from the Solar Zenith Angle, AF-RAD (306.0 nm/325.3 nm) for SZA < 50°, BF-RAD (309.9 nm/325.3 nm) and CF-RAD (317.5 nm/325.3 nm) for SZA > 50°. Considering the OMI ozone data as the reference values, the accuracy of the filter radiometer is estimated to be ±4%. The data collected during the calibration campaign in Lampedusa (June-July 2009, Italy) and during the first Antarctica winter of the 2009-2013 measurement campaign at Mario Zucchelli Station (MZS) are reported. The TOC measured by the F-RAD instrument, by the OMI on board of EOS-Aura satellite (NASA), and by the NOAA UV Monitoring Station in McMurdo (USA) are compared to assess the appropriateness of F-RAD for a long-term measurement campaign. © 2017 Optical Society of America.

The study of lightning phenomena will be carried out by a dedicated instrument, the lightning imager, that will make use of narrow-band transmission filters for separating the Oxygen emission lines in the clouds, from the background signal. The design, manufacturing and testing of these optical filters will be described here. © 2012 ESA and CNES.

Optical systems employed in high-energy environments are subjected to high doses of ionizing radiation and the stability of their optical properties is required to avoid a possible failure of the experiments. Radiation hard glasses are widely used as substrates or windows in high-energy applications, due to their resistance in hostile environments where energetic particles and γ rays are present. In this work, radiation-resistant commercial glass samples were irradiated by 60Co γ rays from 50 to 3 × 105 Gy absorbed doses and at three different dose rates. The optical properties of the samples were measured to evaluate the gamma irradiation effects and the damage recovery after the end of irradiation. A dependence on the irradiation dose rates was found. © 2015 American Ceramic Society and Wiley Periodicals, Inc.

The behavior of optical coatings under low-energy proton irradiation (60 keV) has been investigated, The interaction of protons with coating and substrate was simulated by the SRIM code to understand the effects of proton irradiation. © OSA 2013.