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SESAME (Synchrotron-light for Experimental Science and Application in the Middle East) is a “third-generation” synchrotron light source. The Middle East’s first major international research centre, established as cooperative venture by the scientists and governments of the region, is situated in Jordan. On the basis of the agreement signed between INFN and SESAME, our collaboration has designed and is building a Fluorescence Detector System based on 64 SDDs, each having a 9 mm 2 non-collimated sensitive area, realized with eight monolithic arrays for a total collimated sensitive area of 499 mm 2 . The instrument will be used at the beamline dedicated to x-ray absorption spectroscopy in the energy range 3–30 keV with the capability of reaching a maximum counting rate of at least 3.2 Mcps. The energy resolution required for this application is below 150 eV FWHM @5.9 keV. We plan to have the system completely operative by July 2018. We report on the main building blocks of this system, dedicated to SESAME, and describe the experimental performances measured in the lab and on the XAFS beamline of ELETTRA Sincrotrone Trieste, Italy. In the very first tests the system was successfully operated up to 8 Mcounts/s. The energy resolution below 150 eV @5.9 keV was measured using a 1 . 6 μ s peaking time with the detector cooled to 10 °C.

Third and fourth generation light sources have revolutionized the research in many scientific and technological disciplines. New scientific challenges impose the construction of cutting-edge performance machines and experimental stations. In this context, off-the-shelf detection systems severely constrain the achievable results. These reasons motivated the ReDSoX research project, aiming to explore new solutions related to energy resolving imagers based on Silicon Drift Detectors (SDD), which are among the most employed acquisition devices in X-ray fluorescence spectroscopy. The main goal of the project is to develop novel versatile detection systems able to cover a large photoemission solid angle, being easily adaptable to the needs of different X-ray spectroscopy beamlines and ready to cope with high photon count-rates in order to exploit all the power of new light sources. Research efforts yielded two detector systems, dedicated to different experimental needs. The first system is composed of 32 SDD elements arranged on 4 monolithic sensors and covers a total non-collimated area of 1230 mm2. Such device is optimized for detecting low-energy photons in the 200 – 4000 eV energy range. The second detector consists of a matrix of 64 SDD elements disposed on 8 monolithic arrays covering an overall non-collimated active area of 576 mm2 and operating over an energy range between 4 and 30 keV. Both systems are highly integrated and can either be operated as an apparent large area single detector or as a multi-element detector, collecting information separately from each single element in order to enable spatially and angularly resolved advanced studies. The performances of the two detector systems have been studied at the TwinMic and XAFS beamlines (Elettra Sincrotrone Trieste, Italy), respectively. Recent results obtained during these measurements are presented and discussed.Third and fourth generation light sources have revolutionized the research in many scientific and technological disciplines. New scientific challenges impose the construction of cutting-edge performance machines and experimental stations. In this context, off-the-shelf detection systems severely constrain the achievable results. These reasons motivated the ReDSoX research project, aiming to explore new solutions related to energy resolving imagers based on Silicon Drift Detectors (SDD), which are among the most employed acquisition devices in X-ray fluorescence spectroscopy. The main goal of the project is to develop novel versatile detection systems able to cover a large photoemission solid angle, being easily adaptable to the needs of different X-ray spectroscopy beamlines and ready to cope with high photon count-rates in order to exploit all the power of new light sources. Research efforts yielded two detector systems, dedicated to different experimental needs. The first system is composed of 32 SDD el...

The XAFS beamline at Elettra Synchrotron in Trieste combines X-ray absorption spectroscopy and X-ray diffraction to provide chemically specific structural information of materials. It operates in the energy range 2.4-27 keV by using a silicon double reflection Bragg monochromator. The fluorescence measurement is performed in place of the absorption spectroscopy when the sample transparency is too low for transmission measurements or the element to study is too diluted in the sample. We report on the development and on the preliminary tests of a new prototype detector based on Silicon Drift Detectors technology and the SIRIO ultra low noise front-end ASIC. The new system will be able to reduce drastically the time needed to perform fluorescence measurements, while keeping a short dead time and maintaining an adequate energy resolution to perform spectroscopy. The custom-made silicon sensor and the electronics are designed specifically for the beamline requirements., Comment: Proceeding of the 6YRM 12th-14th Oct 2015 - L'Aquila (Italy). Accepted for publication on Journal of Physics: Conference Series

In recent years, silicon photomultipliers (SiPMs) have been proposed as a new kind of readout device for scintillating detectors in many experiments. A SiPM consists of a matrix of parallel-connected pixels, which are independent photon counters working in Geiger mode with very high gain ( ∼ 10 6 ). This contribution presents the use of an array of eight SiPMs (manufactured by FBK-irst) for the readout of a scintillating bar tracker (a small size prototype of the Electron Muon Ranger detector for the MICE experiment). The performances of the SiPMs in terms of signal to noise ratio, efficiency and time resolution will be compared to the ones of a multi-anode photomultiplier tube (MAPMT) connected to the same bars. Both the SiPMs and the MAPMT are interfaced to a VME system through a 64 channel MAROC ASIC.

In recent years Silicon Photomultipliers (SiPMs) have been proposed as a new type of readout system for scintillating detectors in many experiments. SiPMs consist of a matrix of parallel-connected silicon micro-pixels, which are independent photon counters working in limited Geiger mode with very high gain (∼106). This contribution presents the use of SiPMs (manufactured by FBK-irst) as a readout system of scintillator-lead shashlik calorimeters. The calorimeter under test is composed of 130 tiles (65 of scintillator and 65 of lead) with an area of 11.5×;11.5 cm2 and a total thickness of ∼18 radiation lengths. The scintillation light is readout using 144 wavelength-shifter (WLS) fibers with a diameter of 1.2 mm and brought to large area SiPMs, characterized by a high dynamic range (6400 pixels). A custom board based on the MAROC3 ASIC has been used for the readout of the SiPMs signals. The performances of the calorimeter and of the readout system have been tested at the CERN PS-T9 and the SPS-H2 beamlines with electrons up to 150 GeV.

Silicon PhotoMultipliers are silicon photodetectors that can be used to replace the photomultiplier tubes in many experimental situations. In this article we describe the performance of SiPMs as a readout system of a shashlik calorimeter composed of 70 11.5x11.5 cm2 4 mm thick tiles of scintillator and 69 11.5x11.5 cm2 1.5 mm thick tiles of lead for a total of ~ 19 radiation lengths; the light is collected by 144 1.2 mm wave-length-shifter (WLS) fibers grouped in bundles of nine for a total of 16 channels. The SiPMs are manufactured by FBK-irst and have a sensitive area of 9 mm2. The calorimeter has been tested at CERN using both a low (PS T9 beamline) and high (SPS H4 beamline) energy beam in 2010.

Silicon photomultipliers are silicon devices that in recent times have been proposed as candidates for the replacement of photomultiplier tubes in many experimental situations. In this article we describe the performance of SiPMs as a readout system of a shashlik calorimeter composed of 41 8×8 cm2, 3.27-mm-thick tiles of scintillator and 40 8×8 cm2, 3.27-mm-thick tiles of lead, for a total of ~24 radiation lengths; the light is collected by 64 0.8-mm wave-length-shifter (WLS) fibers grouped in bundles of four for, a total of 16 channels. The SiPMs are manufactured by FBK-irst and have a sensitive area of 1 mm2. The calorimeter has been tested at CERN using both a low (PS T10 beamline) and high (SPS H4 beamline) energy beam during the summer 2009 data taking.

Encephalitis due to the protozoan Toxoplasma gondii has emerged as a common cause of central nervous system disease in patients with acquired immunodeficiency syndrome. Extraneural disease is less common and more difficult to diagnose. We report a case of widely disseminated toxoplasmosis that presented as acute gastrointestinal and pulmonary disease in a patient without a prior diagnosis of acquired immunodeficiency syndrome. The diagnosis of toxoplasmosis was made only at autopsy. Antemortem diagnosis of disseminated T gondii infection requires a high degree of clinical suspicion and the prompt utilization of appropriate diagnostic testing. Since toxoplasmosis is a potentially treatable opportunistic infection, diagnosis allows the swift institution of anti-Toxoplasma therapy.

We describe a variant of carcinoma of the ampulla of Vater, which, to our knowledge, has not been previously described. Classic signet-ring cells represented the predominant cell type, and were admixed with more poorly differentiated tumor cells that were chromogranin positive. These findings raise the possibility of an amphicrine tumor of the ampulla.

A 72-year-old woman had a villous adenoma of endodermal derivation involving the rectovaginal septum and contiguous mucosal surfaces that presented clinically as a vaginal polypoid tumor. To explain the vaginal involvement, we postulate that the adenoma traversed a tract of developmental origin within the rectovaginal septum. This is the first report of such a unique constellation of findings.

We describe a 40-yr-old woman who presented with abdominal pain and diarrhea, and who was found to have segmental colitis involving the cecum and ascending colon. Aeromonas hydrophila was isolated from the stool, and her symptoms responded to appropriate antibiotic therapy. Follow-up colonoscopy confirmed complete endoscopic and histologic resolution of her colitis. This report further supports the belief that Aeromonas species are pathogens in healthy humans. This organism needs to be considered in the differential diagnosis of diffuse and segmental colitis.

We investigated the migration of oil-induced, guinea pig peritoneal macrophages in three-dimensional fibrin matrices, with particular attention to variables which modified fibrin gel structure and/or its adhesive properties for cells. The variables studied were fibrin concentration, gel cross-linking, and fibronectin and glycosaminoglycan content. Macrophage migration was an inverse linear function of fibrinogen concentration. Little or no fibrinolysis accompanied macrophage migration; rather, macrophages migrated through fibrin gels by an active process associated with marked distortions of cell shape and specialized plasma membrane contacts with fibrin strands. Fibrin matrices prepared from fibrinogen that had been depleted of clotting factor XIII and/or fibronectin provided a superior matrix for macrophage migration. Both the number of migrating cells and distance of migration were reduced when the gel matrix included fibronectin and was cross-linked by factor XIII. A hexapeptide containing the fibronectin cell-binding RGDS sequence reversed this migration inhibition, suggesting that fibronectin immobilized by cross-linking to fibrin may have bound macrophages and restricted cell migration. Hyaluronic acid, heparin, and heparan sulfate inhibited macrophage migration in cross-linked fibrin-fibronectin gels over a range of concentrations. These data are relevant to an understanding of macrophage migration in vivo where cross-linked fibrin-fibronectin gels containing variable amounts of glycosaminoglycans are deposited in tissues in immunologic reactions and in many other types of pathology.