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HERMES Pathfinder (High Energy Rapid Modular Ensemble of Satellites Pathfinder) is a space mission based on a constellation of nano-satellites in a low Earth Orbit, hosting new miniaturized detectors to probe the X-ray temporal emission of bright high-energy transients such as Gamma-Ray Bursts and the electromagnetic counterparts of Gravitational Waves. This ambitious goal will be achieved exploiting at most Commercial offthe-shelf components. For HERMES-SP, a custom Power Supply Unit board has been designed to supply the needed voltages to the payload and, at the same time, protecting it from Latch-Up events., SPIE PROCEEDINGS 15 PAGES

Space Telescopes and Instrumentation 2022: Ultraviolet to Gamma Ray (2022), Montreal, Jul 17-22, 2022.--Proceedings of SPIE - The International Society for Optical Engineering vol. 12181 Article number 1218126.-- Full list of authors: Amati, Lorenzo; Labanti, Claudio; Mereghetti, Sandro; Frontera, Filippo; Campana, Riccardo; Auricchio, Natalia; Baldazzi, Giuseppe; Bellutti, Pierluigi; Bertuccio, Giuseppe; Branchesi, Marica; Butler, Reginald C.; Caballero-Garcia, Maria D.; Camisasca, Anna E.; Castro-Tirado, Alberto J.; Cavazzini, Leo; Ciolfi, Riccardo; De Rosa, Adriano; Evangelisti, Federico; Farinelli, Ruben; Ferro, Lisa; Ficorella, Francesco; Fiorini, Mauro; Fuschino, Fabio; Gasent-Blesa, Jose L.; Ghirlanda, Giancarlo; Grassi, Marco; Guidorzi, Cristiano; Hedderman, Paul; Kuvvetli, Irfan; La Rosa, Giovanni; Lorenzi, Paolo; Malcovati, Piero; Marchesini, Ezequiel; Marisaldi, Martino; Melchiorri, Michele; Mele, Filippo; Mikhalska, Malgorzata; Orlandini, Mauro; Orleanski, Piotr; Pedersen, Soren M.; Pizzolla, Raffaele; Rachevski, Alexandre; Rashevskaya, Irina; Rosati, Piero; Reglero, Victor; Ronchini, Samuele; Santangelo, Andrea; Salvaterra, Ruben; Sarra, Paolo; Sortino, Francesca; Sottile, Giuseppe; Stratta, Giulia; Squerzanti, Stefano; Stephen, John B.; Tenzer, Chris; Terenzi, Luca; Trois, Alessio; Vacchi, Andrea; Virgilli, Enrico; Volpe, Angela; Winkler, Marek; Zampa, Gianluigi; Zampa, Nicola; Zdziarski, Andrzej, We describe the science case, design and expected performances of the X/Gamma-ray Imaging Spectrometer (XGIS), a GRB and transients monitor developed and studied for the THESEUS mission project, capable of covering an exceptionally wide energy band (2 keV – 10 MeV), with imaging capabilities and location accuracy, With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709

One of the main priorities of rehabilitation after anterior cruciate ligament reconstruction (ACLR) surgery is the restoration of knee extensor muscle strength. Residual deficits in knee extensor muscle size and strength after injury are linked to poor biomechanics, reduced knee function, increased knee osteoarthritis risk, as well as heightened risk of re-injury upon return to sport. Most studies indicate that knee extensor muscle strength is typically not resolved prior to return to sport. This clinical commentary discusses strategies to optimize and accelerate the recovery of knee extensor strength post-surgery, with the purpose to support the clinician with evidence-based strategies to implement into clinical practice. Principally, two strategies exist to normalize quadriceps strength after surgery, 1) limiting strength loss after injury and surgery and 2) maximizing and accelerating the recovery of strength after surgery. Optimal preparation for surgery and a focused attempt to resolve arthrogenic muscle inhibition are essential in the pre and post-operative period prior to the inclusion of a periodized strength training program. Often voluntary strengthening alone is insufficient to fully restore knee extensor muscle strength and the use of electrical stimulation and where necessary the use of blood flow restriction training with low loads can support strength recovery, particularly in patients who are significantly load compromised and experience pain during exercise. Resistance training should employ all contraction modes, utilize open and closed kinetic chain exercise of both limbs, and progress from isolated to functional strength training, as part of a periodized approach to restoring neuromuscular function. Furthermore, thinking beyond the knee musculature and correcting core and hip dysfunction is also important to ensure an optimal knee extension strengthening program. The purpose of this clinical commentary is to provide a series of evidenced based strategies which can be implemented by clinicians responsible for the rehabilitation of patients after ACLR. Level of evidence 5

UVscope is an instrument, based on a multi-pixel photon detector, developed to support experimental activities for high-energy astrophysics and cosmic ray research. The instrument, working in single photon counting mode, is designed to directly measure light flux in the wavelengths range 300-650~nm. The instrument can be used in a wide field of applications where the knowledge of the nocturnal environmental luminosity is required. Currently, one UVscope instrument is allocated onto the external structure of the ASTRI-Horn Cherenkov telescope devoted to the gamma-ray astronomy at very high energies. Being co-aligned with the ASTRI-Horn camera axis, UVscope can measure the diffuse emission of the night sky background simultaneously with the ASTRI-Horn camera, without any interference with the main telescope data taking procedures. UVscope is properly calibrated and it is used as an independent reference instrument for test and diagnostic of the novel ASTRI-Horn telescope., Comment: Published (Open Access) in "Experimental Astronomy"

HERMES-TP/SP (High Energy Rapid Modular Ensemble of Satellites Technologic and Scientific Pathfinder) is a constellation of six 3U nano-satellites hosting simple but innovative X-ray detectors, characterized by a large energy band and excellent temporal resolution, and thus optimized for the monitoring of Cosmic High Energy transients such as Gamma Ray Bursts and the electromagnetic counterparts of Gravitational Wave Events, and for the determination of their positions. The projects are funded by the Italian Ministry of University and Research and by the Italian Space Agency, and by the European Union Horizon 2020 Research and Innovation Program under Grant Agreement No. 821896. HERMES-TP/SP is an in-orbit demonstration, that should be tested starting from 2022. It is intrinsically a modular experiment that can be naturally expanded to provide a global, sensitive all sky monitor for high-energy transients., Comment: 15 pages, 3 figures, Proceedings of SPIE Astronomical Telescopes and Instrumentation 2020

The European Space Agency's INTErnational Gamma-Ray Astrophysics Laboratory (ESA/INTEGRAL) was launched aboard a Proton-DM2 rocket on 17 October 2002 at 06:41 CEST, from Baikonur in Kazakhstan. Since then, INTEGRAL has been providing long, uninterrupted observations (up to about 47h, or 170ksec, per satellite orbit of 2.7 days) with a large field-of-view (FOV, fully coded: 100 deg), millisecond time resolution, keV energy resolution, polarization measurements, as well as additional wavelength coverage at optical wavelengths. This is realized by two main instruments in the 15keV to 10MeV energy range, the spectrometer SPI (spectral resolution 3keV at 1.8MeV) and the imager IBIS (angular resolution: 12arcmin FWHM), complemented by X-ray (JEM-X; 3–35keV) and optical (OMC; Johnson V-band) monitor instruments. All instruments are co-aligned to simultaneously observe the target region. A particle radiation monitor (IREM) measures charged particle fluxes near the spacecraft. The Anti-coincidence subsystems of the main instruments, built to reduce the background, are also very efficient all-sky γ-ray detectors, which provide virtually omni-directional monitoring above ∼75keV. Besides the long, scheduled observations, INTEGRAL can rapidly (within a couple of hours) re-point and conduct Target of Opportunity (ToO) observations on a large variety of sources. INTEGRAL observations and their scientific results have been building an impressive legacy: The discovery of currently more than 600 new high-energy sources; the first-ever direct detection of Ni and Co radio-active decay lines from a Type Ia supernova; spectroscopy of isotopes from galactic nucleo-synthesis sources; new insights on enigmatic positron annihilation in the Galactic bulge and disk; and pioneering gamma-ray polarization studies. INTEGRAL is also a successful actor in the new multi-messenger astronomy introduced by non-electromagnetic signals from gravitational waves and from neutrinos: INTEGRAL found the first prompt electromagnetic radiation in coincidence with a binary neutron star merger. Up to now more than 1750 scientific papers based on INTEGRAL data have been published in refereed journals. In this paper, we will give a comprehensive update of the satellite status after more than 18 years of operations in a harsh space environment, and an account of the successful Ground Segment., Kuulkers, Erik, et al., he OMC team has been funded by different Spanish grants, including Spanish State Research Agency grants PID2019–107061GB–C61 and MDM–2017-0737 (Unidad de Excelencia María de Maeztu – CAB). The INTEGRAL French teams acknowledge partial funding from the French Space Agency (CNES). The Danish JEM-X gratefully acknowledges support from the Danish PRODEX delegation through contract C90057. The INTEGRAL Italian team acknowledges support form the Italian Space Agency, ASI, along these years via different agreements, last of which is 2019–35-HH.0. LH acknowledges support from SFI under grant 19/FFP/6777 and the EU AHEAD2020 project (grant agreement 871158). MH acknowledges support from Spanish MICINN grant PID2019-108709GB-I00. TS is supported by the German Research Society (DFG-Forschungsstipendium SI 2502/1-1 & SI 2502/3-1).

The HERMES-TP/SP (High Energy Rapid Modular Ensemble of Satellites -- Technologic and Scientific Pathfinder) is an in-orbit demonstration of the so-called distributed astronomy concept. Conceived as a mini-constellation of six 3U nano-satellites hosting a new miniaturized detector, HERMES-TP/SP aims at the detection and accurate localisation of bright high-energy transients such as Gamma-Ray Bursts. The large energy band, the excellent temporal resolution and the wide field of view that characterize the detectors of the constellation represent the key features for the next generation high-energy all-sky monitor with good localisation capabilities that will play a pivotal role in the future of Multi-messenger Astronomy. In this work, we will describe in detail the temporal techniques that allow the localisation of bright transient events taking advantage of their almost simultaneous observation by spatially spaced detectors. Moreover, we will quantitatively discuss the all-sky monitor capabilities of the HERMES Pathfinder as well as its achievable accuracies on the localisation of the detected Gamma-Ray Bursts., 19 pages, 13 figures, Proceedings of SPIE Astronomical Telescopes and Instrumentation 2020

It is important to optimise the functional recovery process to enhance patient outcomes after major injury such as anterior cruciate ligament reconstruction (ACLR). This requires in part more high-quality original research, but also an approach to translate existing research into practice to overcome the research to implementation barriers. This includes research on ACLR athletes, but also research on other pathologies, which with some modification can be valuable to the ACLR patient. One important consideration after ACLR is the recovery of hamstring muscle function, particularly when using ipsilateral hamstring autograft. Deficits in knee flexor function after ACLR are associated with increased risk of knee osteoarthritis, altered gait and sport-type movement quality, and elevated risk of re-injury upon return to sport. After ACLR and the early post-operative period, there are often considerable deficits in hamstring function which need to be overcome as part of the functional recovery process. To achieve this requires consideration of many factors including the types of strength to recover (e.g., maximal and explosive, multiplanar not just uniplanar), specific programming principles (e.g., periodised resistance programme) and exercise selection. There is a need to know how to train the hamstrings, but also apply this to the ACLR athlete. In this paper, the authors discuss the deficits in hamstring function after ACLR, the considerations on how to restore these deficits and align this information to the ACLR functional recovery process, providing recommendation on how to recover hamstring function after ACLR.

HERMES (High Energy Rapid Modular Ensemble of Satellites) Technological and Scientific pathfinder is a space borne mission based on a LEO constellation of nano-satellites. The 3U CubeSat buses host new miniaturized detectors to probe the temporal emission of bright high-energy transients such as Gamma-Ray Bursts (GRBs). Fast transient localization, in a field of view of several steradians and with arcmin-level accuracy, is gained by comparing time delays among the same event detection epochs occurred on at least 3 nano-satellites. With a launch date in 2022, HERMES transient monitoring represents a keystone capability to complement the next generation of gravitational wave experiments. In this paper we will illustrate the HERMES payload design, highlighting the technical solutions adopted to allow a wide-energy-band and sensitive X-ray and gamma-ray detector to be accommodated in a CubeSat 1U volume together with its complete control electronics and data handling system., Comment: 12 pages, 13 figures. Proceedings of SPIE "Astronomical Telescopes and Instrumentation" 2020

ASTRI-Horn is a prototypal telescope of an imaging atmospheric Cherenkov telescope developed by the Italian National Institute of Astrophysics (INAF), proposed for the Cherenkov Telescope Array (CTA) Observatory. The CTA Observatory represents the next generation of imaging atmospheric Cherenkov telescopes and will explore the very highenergy domain from a few tens of GeV up to few hundreds of TeV. It will be composed of large-, medium-, and small sized telescopes; ASTRI-Horn is an end-to-end prototype proposed for the Small Sized array. The main scientific instrument of the ASTRI-Horn telescope is an innovative and compact Camera with Silicon- Photomultiplier based detectors and a specifically designed fast read-out electronics based on a custom peak-detector mode. The thermo-mechanical assembly is designed to host both the entire electronics chain, from the sensors to the raw data transmission system and the calibration system, and the complete thermoregulation system. This contribution gives a high level description of the T/M and electrical design of the Cherenkov Camera, it describes the assembling procedure of its different subsystems and their integration into the complete camera system. A discussion about possible design improvements coming from the problems/difficulties encountered during assembly is also presented. Finally, results from engineering tests conducted in-field are also presented.

The Cherenkov Telescope Array (CTA) foresees, in its southern site (Chile), the implementation of up to 70 small-sized telescopes (SSTs), which will extend the energy coverage up to hundreds of TeV. It has been proposed that one of the first set of CTA SSTs will be represented by the ASTRI mini-array, which includes (at least) nine ASTRI telescopes. The endto-end prototype of such telescopes, named the ASTRI SST-2M, is installed in Italy and it is now completing the overall commissioning and entering the science verification phase. ASTRI telescopes are characterized by an optical system based on a dual-mirror Schwarzschild-Couder design and a camera at the focal plane composed of silicon photomultiplier sensors managed by a fast read-out electronics specifically designed. Based on a custom peak-detector mode, the ASTRI camera electronics is designed to perform Cherenkov signal detection, trigger generation, digital conversion of the signals and data transmission to the camera server. In this contribution we will describe the main features of the ASTRI camera, its performance and results obtained during the commissioning phase of the ASTRI SST-2M prototype in view of the ASTRI mini-array implementation.

The purpose of this contribution is to present the current status of the software architecture of the ASTRI SST-2M Cherenkov Camera. The ASTRI SST-2M telescope is an end-to-end prototype for the Small Size Telescope of the Cherenkov Telescope Array. The ASTRI camera is an innovative instrument based on SiPM detectors and has several internal hardware components. In this contribution we will give a brief description of the hardware components of the camera of the ASTRI SST-2M prototype and of their interconnections. Then we will present the outcome of the software architectural design process that we carried out in order to identify the main structural components of the camera software system and the relationships among them. We will analyze the architectural model that describes how the camera software is organized as a set of communicating blocks. Finally, we will show where these blocks are deployed in the hardware components and how they interact. We will describe in some detail, the physical communication ports and external ancillary devices management, the high precision time-tag management, the fast data collection and the fast data exchange between different camera subsystems, and the interfacing with the external systems.

ASTRI SST-2M is the end-to-end prototype telescope under development by the Italian National Institute of Astrophysics, INAF, proposed for the investigation of the highest-energy gamma-ray band in the framework of the Cherenkov Telescope Array, CTA. The ASTRI SST-2M prototype will be installed in Italy at the INAF station located at Serra La Nave on Mount Etna during Fall 2014. The calibration and scientific validation phase will start soon after. The calibration of a Cherenkov telescope includes several items and tools. The ASTRI SST- 2M camera is equipped with an internal fiber illumination system that allows to perform the relative calibration through monitoring of gain and efficiency variations of each pixel. The absolute calibration of the overall system, including optics, will take advantage from auxiliary instrumentation, namely UVscope and UVSiPM, two small-aperture multi-pixels photon detectors NIST calibrated in lab. During commissioning phase, to measure the main features of ASTRI SST-2M, as its overall spectral response, the main telescope and the auxiliary UVscope-UVSiPM will be illuminated simultaneously by a spatially uniform flux generated by a ground-based light source, named Illuminator, placed at a distance of few hundreds meters. Periodically, during clear nights, the flux profiles of a reference star tracked simultaneously by ASTRI SST-2M and UVscope-UVSiPM will allow to evaluate the total atmospheric attenuation and the absolute calibration constant of the ASTRI SST-2M prototype. In this contribution we describe the auxiliary UVscope-UVSiPM and Illuminator sub-system together with an overview of the end-to-end calibration procedure foreseen for the ASTRI SST-2M telescope prototype.

The Cherenkov Telescope Array (CTA) is a worldwide new gene ration project aimed at realizing an array of a hundred ground based gamma-ray telescopes. ASTRI (Astrofisica con Specchi a Tecnologia Replicante Italiana) is the Italian project whose primary target is the development of an end-to-end prototype, named ASTRI SST-2M, of the CTA small size class of telescopes devoted to investigation of the highest energy region, from 1 to 100 TeV. Next target is the implementation of an ASTRI/CTA mini-array based on seve n identical telescopes. Silicon Photo-Multipliers (SiPMs) are the semiconductor photosensor devices designated to constitute the camera detection system at the focal plane of the ASTRI telescopes. SiPM photosensors are suitable for the detection of the Cherenkov flashes, since they are very fast and sensitive to the light in the 300-700nm wavelength spectrum. Their drawbacks compared to the traditional photo-multiplier tubes are high dark count rates, after-pulsing and optical cross-talk contributions, and intrinsic gains strongly dependent on temperature. Nonetheless, for a single pixel, the dark count rate is well below the Night Sky Background, the effects of cross-talk and afterpulses are typically lower th an 20%, and the gain can be kept stable against temperature variations by means of adequate bias voltage compensation strategies. This work presents and discusses some experimental results from a large set of measurements performed on the SiPM sensors to be used for the ASTRI SST-2M prototype camera and on recently developed detectors demonstrating outstanding performance for the future evolution of the project in the ASTRI/CTA mini-array. Keywords: ASTRI, CTA, detectors, characterizations, phot on detection efficiency, silicon photomultipliers.

In the context of the Cherenkov Telescope Array observatory project, the ASTRI SST-2M end-to-end prototype telescope, entirely supported by the Italian National Institute of Astrophysics, is designed to detect cosmic primary gamma ray energies from few TeV up to hundreds of TeV. The ASTRI SST-2M prototype camera is part of the challenging synergy of novel optical design, camera sensors, front-end electronics and telescope structure design. The camera is devoted to imaging and recording the Cherenkov images of air showers induced by primary particles into the Earth’s atmosphere. In order to match the energy range mentioned above, the camera must be able to trigger events within a few tens of nanoseconds with high detection efficiency. This is obtained by combining silicon photo-multiplier sensors and suitable front-end electronics. Due to the characteristic imprint of the Cherenkov image that is a function of the shower core distance, the signal dynamic range of the pixels and consequently of the front-end electronics must span three orders of magnitude (1:1000 photo-electrons). These and many other features of the ASTRI SST-2M prototype camera will be reported in this contribution together with a complete overview of the mechanical and thermodynamic camera system.

The present paper is intended to implement and simulate the Extended Analogue Silicon-photomultiplier Integrated Read-Out Chip (EASIROC) fully analogue front-end model, in order to investigate its foremost characteristics and demonstrate its practical effectiveness when its analogue inputs are driven by the silicon photomultiplier (SiPM) signals. The circuit models of all functional blocks are described. Frequency and dynamic features of all circuit front-end sections are briefly addressed, and design mathematical equations are derived as well. PSPICE simulations of each single model are carried out to analyse and confirm its analogue behaviour.

The technique which combines high resolution spectroscopy with imaging capability is a powerful tool to extract fundamental information in X-ray Astrophysics and Cosmology. TES (Transition Edge Sensors)-based microcalorimeters match at best the requirements for doing fine spectroscopy and imaging of both bright (high count rate) and faint (poor signal-to-noise ratio) sources. For this reason they are considered among the most promising detectors for the next high energy space missions and are being developed for use on the focal plane of the IXO (International X-ray Observatory) mission. In order to achieve the required signal-to-noise ratio for faint or diffuse sources it is necessary to reduce the particle-induced background by almost two orders of magnitude. This reduction can only be achieved by adopting an active anticoincidence technique. In this paper, we will present a novel anticoincidence detector based on a TES sensor developed for the IXO mission. The pulse duration and the large area of the IXO TESarray (XMS X-ray Microcalorimeter Spectrometer) require a proper design of the anticoincidence detector. It has to cover the full XMS area, yet delivering a fast response. We have therefore chosen to develop it in a four-pixel design. Experimental results from the large-area pixel prototypes will be discussed, also including design considerations.

Intra-arterial Nimodipine administration can be an effective alternative to papaverine or balloon angioplasty for the treatment of cerebral vasospasm refractory to medical therapy. It has been used for intractable vasospasm due to aneurysmal subarachnoid haemorrhage (SAH) with convincing results and no significant complications in small case series. This report describes of a patient with symptomatic and angiographically documented vasospasm following traumatic SAH which was refractory to maximal medical therapy and successfully treated with intra-arterial infusion of Nimodipine. This first reported technical note is with special reference to the nimodipine administration modalities, clinical and neuroradiological criteria of selection as well as the follow up of the patient.

Cochlear implantation (CI) may induce vestibular impairment soon after surgery as well as after implant activation. This impairment seems to be independent from the cause of deafness and can be considered a possible complication from the intra-operative trauma and, to minor degree, from the ongoing electric stimulation. It would also seem that vestibular damage occurs independently from the likelihood of post-operative hearing deterioration. In unilateral selected CI cases, vestibular examination can be proposed as additional pre-operative exam for selection of the ear to be implanted.This study has been planned in order to get evidence of eventual impairment of the vestibular apparatus after cochlear implantation as well as to verify whether the impairment could be related to different variables, such as cause of deafness, concomitant hearing deterioration, surgical trauma and duration of electrical stimulation.Charts from two different populations of implantees have been reviewed, 21 from a prospective, 72 from a retrospective study, respectively. All the patients were implanted with Clarion(R) devices of different generation. Vestibular testing was based on rotatory, caloric (when possible) and stabilometric measurements, which were carried out pre-operatively and at the following different times: 5 weeks after CI surgery, and 30, 60 and 90 days after CI activation. Hearing thresholds were also assessed in those patients who showed signs of vestibular impairment as well as in a group of patients without vestibular disorders (control). Patients belonging to the retrospective group were all asked to fill a questionnaire regarding their balance condition. Results. In 14.3% of the prospective study group, a grade I and II spontaneous nystagmus was evidenced pre-operatively and remained unchanged during the whole assessment period. A grade II spontaneous nystagmus was present in 3 patients (21.4%) of the same group after surgery. In the immediate post-operative period, vestibular impairment was displayed as true rotational vertigo in 21.4% and unsteadiness in 42.8% of the study group. Severe unsteadiness was present during the first 2 days after activation in 14.3% of the subjects. In 21.4% of the patients a VPPB episode occured. In the retrospective study group, 26.4% of the subjects referred pre-operative dizziness and 25 patients (34.7%) referred immediate post-operative vertigo episodes, which remained in a milder form after CI activation in 12% of them. The hearing threshold showed to deteriorate in both vestibular-impaired and control CI population without significant difference.

The IBIS telescope is the high angular resolution Gamma-Ray imager on-board the ESA satellite INTEGRAL. The scientific goal of IBIS is to address, complemented by the high resolution spectrometer (SPI), astrophysical processes from celestial sources and diffuse regions in the X and Gamma-Ray domain. IBIS, with its Cadmium Telluride detector of 16.384 pixels and Caesium Iodide detector of 4.096 pixels, is an instrument with an high degree of complexity, whose status is continuously monitored by thousands of parameters (count rates, temperatures, voltages, instruments status, etc.), transmitted to ground by the periodic and non-periodic satellite telemetry housekeeping packets. In this paper we present the 'Ibis Parameters MONitor' (IPAMON), the real-time quick look software, part of the IBIS Experiment Check Out Equipment (ECOE), used during the on-ground functional and calibration campaign of the IBIS flight model carried out in LABEN (Milano) and ESTEC (ESA, Noordwijk). Due the high number of parameters, the software was designed to be flexible. In fact using the instrument data base as input for the internal structure configuration, the software is then insensitive to modifications that can occurs in the contents of the packet telemetry. This capability allows IPAMON to be easily used for any other mission involving ESA packet structured telemetry.

The gamma-ray telescope IBIS, on Board the INTEGRAL satellite, is expected to satisfy the mission's imaging objectives, by using two position sensitive detection planes, one with 16384 Cadmium Telluride pixels (ISGRI) at lower energies and the other with 4096 Caesium Iodide pixels (PICsIT) for higher energy detection. Given to the high complexity of the system, a dedicated Experiment Check Out Equipment (ECOE), was developed, capable not only to acquire, archive and monitor, the instrument data, but also to perform a fast data analysis, in order to deeply understand the instrument behavior in real-time. The system was used to support the IBIS Test and Calibration campaign campaigns, from the Engineering to the Flight model, and it will be used again during the Commissioning Phase, after launch. We describe here, the architecture of the ECOE system and the quick-look analysis tools that, with an user friendly graphical interface, allows the user to analyze, in an easy way, both the IBIS housekeeping and scientific data.

Objects: There is a distinct challenge in bringing modern insights into glial tumour genesis to bear on improved outcomes for patients. Insights provided by neuroncological, neuroradiological, neuropathological, and neurosurgical investigations may offer significant advantages in the management of paediatric GBM. The goal of this study was to evaluate angiogenesis as a potential indicator of survival in paediatric glioblastoma multiforme (GBM). Methods: Angiogenesis was evaluated in six cases of paediatric GBM with multiple criteria, including contrast enhancement on preoperative CT scan, histological vascular hyperplasia (VH) and endothelial proliferation (EP) and immunohistochemical tenascin-C (TN-C) expression. We employed a semiquantitative scale, ranging from not detected (zero) to marked (+3), for each investigational parameter. We evaluated the influence of angiogenesis on survival in each case. Conclusions: In this preliminary study, angiogenesis provided information that correlated with survival, albeit in a limited number of patients. As we gain better understanding of the molecular biology of brain tumours, with the multitude of genetic alterations and growth factors new therapeutic approaches may emerge, which may hold the promise for cure.

The balloon borne experiment, named BABY (BAckground BYpass) belongs to a wider program, AIRWATCH-OWL, intended for the observation of high energy Cosmic Rays from space, detecting the faint UV fluorescence light emitted by the atmospheric Nitrogen as final result of a complex hadronic cascade. In this framework, one of the fundamental information concern the knowledge of the background level. This is one of the main parameters that contribute to the sensitivity of any kind of instrument. The apparatus used for the BABY experiment was designed and completely built at the IFCAI-CNR in Palermo. The instrument is composed by two filtered and collimated photomultipliers (PMT) that detect the UV light in the 300–400 nm wavelength. We report a brief description of the design of the detector and the results coming from a preliminary analysis of the data taken during a nocturnal over-sea observation.

The balloon borne experiment, named BABY (BAckground BYpass) belongs to a wider program, AIRWATCH-OWL, intended for the observation of high energy Cosmic Rays from space, detecting the faint UV fluorescence light emitted by the atmospheric Nitrogen as final result of a complex hadronic cascade. In this framework, one of the fundamental information concern the knowledge of the background level. This is one of the main parameters that contribute to the sensitivity of any kind of instrument. The apparatus used for the BABY experiment was designed and completely built at the IFCAI-CNR in Palermo. The instrument is composed by two filtered and collimated photomultipliers (PMT) that detect the UV light in the 300-400 nm wavelength. We report a brief description of the design of the detector and the results coming from a preliminary analysis of the data taken during a nocturnal over-sea observation.

A basic problem in an AIRWATCH based experiment is the development of suitable trigger, read-out and data handling techniques. Considering a matrix of image elements to read- out, ideally one would like to have as many position and timing channels as pixels in the image, but for obvious practical and cost reasons, this solution is not always applicable. In fact the complexity of the electronics demanding a huge amount of channels, is not generally suitable for mission base don satellites, where stringent limitations are present for what concerns power supply, weight and telemetry. One way to deal with such a problem, in the assumption of using a fast detector capable of detecting single photoelectron, is to reduce the number of position and timing channels without significant loss of performance. We present a modular read-out electronics system called 'FIRE'. The modular hierarchical organization of FIRE allow to register X-Y position and arrival time of the single photoelectrons. To check the validity of the method, a set of simulated data was produced and analyzed. Results are illustrated both for the read-out performance and the event reconstruction efficiency.

We report preliminary measurements of the air UV fluorescence light yield as a function of pressure using as a stimulus hard x-rays. For comparison measurements in pure nitrogen are also reported. Knowledge of the air UV fluorescence light yield induced by hard x-rays is needed in order to evaluate the capability to detect, in an AIRWATCH FROM SPACE experiment, Gamma Ray Burst (GRB) events. The experiment was carried out a the LAX x-ray facility in Palermo, by using an high flux collimated x-ray photon beam. The experimental result indicate that the fluorescence yield is inversely proportional to the filling pressure. At pressures below 30 mbar, corresponding to the value for the upper atmospheric layers in which the X and gamma ray photons of the GRBs are absorbed, about 0.1 percent of the total energy of a GRB is transformed in UV photons. This makes possible the observation of the GRBs with the technique proposed in the AIRWATCH FROM SPACE experiment.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

✓ Primary intramedullary melanoma is a very rare tumor that occurs most frequently in the middle or lower thoracic spinal cord. The authors present a case of primary cervical cord melanoma that developed in a 62-year-old man who was surgically treated and subsequently underwent radiation therapy. Clinical and histogenetic features of this neoplasm and results of chemo-, radio-, and immunotherapy are reported. Both “dysembryogenetic” and “mesodermal” hypotheses on the origin of primary spinal melanoma are discussed.

The scientific instrumentation on board the X-ray Astronomy Satellite BeppoSAX, launched at the end of April 1996,includes four identical Mirror Units, each composed of 30 nested grazing incidence mirrors. The focal plane detectors are 3identical position sensitive Medium Energy Gas Scintillation Proportional Counters, operating in the energy range 1.3-10keV and 1 Low Energy Gas Scintillation Proportional Counter in the range 0. 1-10 keV. During the Science VerificationPhase (July-November 96) a selected number of X-ray targets has been observed in order to have an in-flight calibration ofthe instrument. This paper describes some results with particular emphasis to the on axis and off axis behaviour of theoptical systems.Keywords: X-ray optics, X-ray spectrometers, X-ray imaging, X-ray astronomical payloads. 1. INTRODUCTION 1.1 Scientific objectivesThe X-ray astronomy satellite SAX ', named BeppoSAX after launch, in honour of Giuseppe (Beppo) Occhialim, is amajor program of the Italian Space Agency (ASI) with the participation ofthe Netherlands Agency for Aerospace Programs

The scientific instrumentation on board the x-ray astronomy satellite SAX includes a medium energy concentrator/spectrometer (MECS), operating in the energy range 1.3 - 10 keV, which consists of three identical instruments, each composed by a grazing incidence mirror unit with focal length of 1850 mm and by a position sensitive gas scintillation proportional counter. The MECS flight instruments have been calibrated at the X-ray PANTER facility of the Max Planck Institute and the preliminary results are presented in the paper.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

We present the performance characteristics of a High Tech scientific model of the High Pressure Gas Scintillation Proportional Counter (HPGSPC) that has been developed as a prototype detector for the Italian X-ray Astronomy satellite SAX. We give some insight on the technology employed and we give an outline of one of the main areas of interest for the HPGSPC in the framework of the SAX mission.

The scientific model of the SAX Medium Energy Gas Scintillation Proportional Counter has been tested at the PANTER X-ray facility in Munich. For part of the test the detector has been coupled to a representative reduced model of the SAX concentrators model. The results from the tests on both the detector and the detector/mirror assembly are within the expected performances. We have measured an energy resolution of about 8% (FWHM) and an angular resolution (on axis) of 1.3 arcminutes (HPR) at 6.4 keV.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Anterior thoracic intradural arachnoid cysts (ATIACs) are a rare cause of spinal cord and nerve root compression, for which different treatment strategies have been proposed. Although ATIAC represents a well-known clinical entity, the choice of surgical method has not been uniform, and no study has been specifically designed to compare the results of the different treatment options adopted. The authors report the case of a 40-year old man with a 1-year history of dorsal pain, weakness in the lower extremities, gait disturbance, and mild sexual and urinary dysfunction. On neurological examination spastic paraparesis, lower-extremity hypertonia, and hypesthesia below T-2 were demonstrated. Magnetic resonance imaging revealed the presence of an ATIAC at the T-2 level. The patient underwent complete microsurgical removal of the cyst. The authors conducted a Medline search of the relevant literature from 1966 to 1998 and also obtained data on other cases in which patients underwent surgical treatment of ATIAC. The literature search yielded five such cases. Treatment strategies were complete excision and fenestration followed by placement of a shunt. In addition, one case was characterized by intraoperative cyst rupture during retraction of the spinal cord. Correct preoperative workup coupled with microneurosurgical technique allow for successful removal of the lesion and excellent outcome. Based on the literature review and the results in our case, the complete excision of ATIAC is associated with an excellent outcome, which is different from results achieved using other surgical strategies.

Spinal epidural hematomas (SEHs) are uncommon complications caused by traumatic injuries to the spine. Emergency surgical evacuation is the standard treatment. Although recognized in the literature, the possibility of nonsurgical treatment of traumatic SEHs is far from being codified. The authors report on the treatment of four patients whose traumatic SEHs were diagnosed by magnetic resonance (MRI) imaging and managed conservatively with excellent results. All patients had suffered severe spine injury with fracture of a lumbar vertebral body, were admitted within 12 hours of trauma, and exhibited only minimal neurological disturbances on admission. Magnetic resonance imaging studies were performed within 24 hours of trauma. Hematomas appeared isointense/slightly hyperintense on T1- and heterogeneous on T2-weighted MR images. Clot thickness varied between 0.8 cm and 1 cm, width between 1 cm and 1.8 cm, and length between 2.7 and 9 cm. In light of each patient's fairly good neurological condition a conservative approach was taken. In all cases serial MR imaging documented progressive clot resolution, which was completed within 8 to 10 days of trauma. At discharge all patients were neurologically intact. The conservative treatment option of traumatic SEH should be reserved for exceptional cases whose deficits are minimal, when neurological deterioration is followed by early and sustained spontaneous recovery, and when there are clear medical contraindications for surgery. The results of the present study confirm that nonsurgical treatment is feasible in a subgroup of minimally symptomatic patients who harbor moderate-sized SEHs. Although the authors' experience shows a good spontaneous outcome of some traumatic SEH, further studies are necessary to understand the real spectrum of nonsurgical treatment of such lesions.

Primary intramedullary melanoma is a very rare tumor, most frequently occurring in the middle or lower thoracic spinal cord. The authors present a new case of primary cervical cord melanoma that developed in a 62-year-old man whose tumor was surgically treated and subsequently received radiation therapy. Clinical and histogenetic features of this neoplasm, results of chemo-, radio-, and immunotherapy are reported. Both “disembryogenetic” and “mesodermal” hypotheses on the origin of primary spinal melanoma are discussed.

✓ Two patients with recently ruptured intracranial aneurysms underwent surgical repair of these vascular lesions. Postoperatively, they showed clinical and laboratory evidence of disseminated intravascular coagulation (DIC). In both patients severe cerebral ischemic complications occurred. In one case the ischemic complications and the hematological changes were successfully reversed. This syndrome is a potential complication of aneurysmal subarachnoid hemorrhage (SAH), which requires prompt diagnosis and appropriate management. The relationship between hematological changes suggesting DIC and the ischemic complications of SAH should be extensively investigated.

Summary: The present pharmacokinetic study was designed to investigate the possible interaction between valproic acid (VPA) and ethosuximide (ESM) in humans. Six drug-free healthy volunteers, four men and two women, 18–42 years of age, received a single oral dose of 500 mg ESM before and during a treatment with VPA at 800- to 1,600-mg daily doses. The second ESM dose was given 9 days after VPA administration was started. In this latter condition, a significant (p < 0.05) increase in ESM serum half-life, from 44 to 54 h on average, and a significant (p < 0.05) decrease in total body clearance, from 11.2 to 9.5 ml/min on average, were observed. Other pharmacokinetic parameters were unchanged and showed values similar to those reported in the literature. Serum VPA levels ranged between 66.8 and 95 μg/ml. Two subjects showed no evidence of interaction. Although a great interindividual variability in the occurrence of VPA-ESM interaction can be observed, the present study indicates that VPA is able to inhibit the metabolism of ESM. Possible factors affecting this interaction are hypothesized and discussed. RESUME Cette etude pharmacocinetique avait pour but ďetudier Ľin-teraction possible entre Ľacide valproique (VPA) et Ľethosux-imide (ESM) chez Ľhomme. Six volontaires sains, non traites. 4 hommes et 2 femmes, âges de 18 a 42 ans, ont recu une dose orale unique de 500 mg ďESM avant et pendant un traitement par le VPA aux doses de 800 a 1600 mg/jour. La seconde dose ďESM a ete donnee 9 jours apres le debut du VPA. Dans ce dernier cas, une augmentation significative (p < 0,051 de la demi-vie serique de ĽESM, de 44 a 54 heures en moyenne, et une diminution significative (p < 0,05) de la clearance corporelle totale, de 11,2 a 9,5 ml/min en moyenne, ont ete observees. Les autres parametres pharmacocinetiques n'ont pas ete modifyes et leurs valeurs etaient semblables a celles rapportees dans la literature. Les taux seriques de VPA se situaient entre 66,8 et 95 μg/ml. Chez deux sujets aucune interaction n'a ete mise en evidence. Bien qu'une grande variabilitye puisse etre observee ďun individu aĽautre dans la survenue de Ľinteraction VPA-ESM, cette etude indique que le VPA est capable ďinhiber le metab-olisme de ĽESM. Les auteurs discutent les facteurs qui pour-raient influencer cette interaction. RESUMEN Este estudio farmacocinetico ha sido disenado para investigar la posible interaccion entre el acido valproico (VPA) y la eto-suximida (ESM) en humanos. Seis voluntarios sanos sin medi-cacion, 4 hombres y 2 mujeres de 18 a 42 anos, recibieron una dosis unica oral de 500 mg de ESM, antes y durante un trata-miento con VPA de 800–1600 mg diarios. La segunda dosis de ESM se administero 9 dias despues del comienzo del VPA. En esta ultima situacion se observo un aumento significativo (p < 0.05) de la vida media serica de la ESM, con un promedio de 44 a 54 horas y una reduccion signifiativa (p < 0.05) del aclara-miento corporal total de 11.2 a 9.5 ml/min, como promedio. Otros parametros farmacocineticos no cambiaron y mostraron valores semejantes a los publicados en la literatura. Los niveles sericos del VPA oscilaron entre 66.8 y 95 μg/ml. Dos sujetos no mostraron evidencia de interaccion. Aunque se puede observar una gran variabilidad interindividual en la presencia de interaccion VPA-ESM, el presente estudio indica que el VPA es capaz de inhibir el metabolismo de la ESM. Se discuten las hipotesis y los posibles factores que afectan la interaccion descrita. ZUSAMMENFASSUNG Pharmakokinetische Untersuchung uber die Interaktion von Valproinsaure (VPA) und Ethosuximid (ESM) beim Menschen. 6 gesunde Freiwillige ohne Medikation, 4 Manner und 2 Frauen, 18 bis 42 Jahre alt, erhielten eine einmalige orale Dosis von 500 mg ESM vor und wahrend einer Behandlung mit VPA in tag-lichen Dosen von 800 bis 1600 mg. Die zweite ESM-Dosis wurde 9 Tage nach Beginn des VPA gegeben. Unter dieser Bedingung fand sich eine signifikante (p < 0.05) Erhohung der Halbwerts-zeit des ESM durchschnittlich von 44 auf 54 Stunden und ein signifikanter (p < 0,05) Abfall der Gesamtkorperclearance von durchschnittlich 11,2 auf 9,5 ml/Min. Andere pharmakokinetische Parameter blieben unverandert und zeigten Werte, die denen entsprechen. die in der Literatur berichtet werden. Die Serumspiegel von VPA lagen zwischen 66,8 und 95 mg/ml. Zwei Probanden zeigten keine Hinweise auf eine Interaktion. Obwohl eine grose interindividuelle Variabilitat zwischen VPA und ESM Interaktion beobachtet werden kann, zeigt diese Untersuchung, das VPA fahig ist, den Metabolismus des ESM zu inhibieren. Die moglichen Faktoren dieser Interaktionen sind hypothetisch und werden diskutiert.

The detection of Cerenkov light from EAS in a delayed coincidence with fluorescence light gives a strong signature to discriminate protons and neutrinos in cosmic rays. For this purpose, the ULTRA experiment has been designed with 2 detectors: a small EAS array (ETscope) and an UV optical device including wide field (Belenos) and narrow field (UVscope) Cerenkov light detectors. The array measures the shower size and the arrival direction of the incoming EAS, while the UV devices, pointing both to zenith and nadir, are used to determine the amount of direct and diffused coincident Cerenkov light. This information, provided for different diffusing surfaces, will be used to verify the possibility of detecting from Space the Cerenkov light produced by UHECRs with the EUSO experiment, on board the ISS.

GrailQuest (Gamma-ray Astronomy International Laboratory for Quantum Exploration of Space-Time) is an ambitious astrophysical mission concept that uses a fleet of small satellites whose main objective is to search for a dispersion law for light propagation in vacuo. Within Quantum Gravity theories, different models for space-time quantization predict relative discrepancies of the speed of photons w.r.t. the speed of light that depend on the ratio of the photon energy to the Planck energy. This ratio is as small as 10-23 for photons in the γ- ray band (100 keV). Therefore, to detect this effect, light must propagate over enormous distances and the experiment must have extraordinary sensitivity. Gamma-Ray Bursts, occurring at cosmological distances, could be used to detect this tiny signature of space-time granularity. This can be obtained by coherently combine a huge number of small instruments distributed in space to act as a single detector of unprecedented effective area. This is the first example of high-energy distributed astronomy: a new concept of modular observatory of huge overall collecting area consisting in a fleet of small satellites in low orbits, with sub-microsecond time resolution and wide energy band (keV-MeV). The enormous number of collected photons will allow to effectively search these energy dependent delays. Moreover, GrailQuest will allow to perform temporal triangulation of impulsive events with arc-second positional accuracies: an extraordinary sensitive X-ray/Gamma all-sky monitor crucial for hunting the elusive electromagnetic counterparts of Gravitational Waves, that will play a paramount role in the future of Multi-messenger Astronomy. A pathfinder of GrailQuest is already under development through the HERMES (High Energy Rapid Modular Ensemble of Satellites) project: a fleet of six 3U cube-sats to be launched by the end of 2022.

The technological development of the Medium Energy Gas Scintillation Proportional Counter (MEGSPC), a part of the scientific payload of the Italian-Dutch X-ray Astronomy Satellite SAX, is presented. The detector and the experimental setup are briefly described and its detector performance characteristics are given. Experimental findings on the background resolution and spatial resolution are reported and the background rejection is discussed.

Object. Posterolateral fusion involving instrumentation-assisted segmental fixation represents a valid procedure in the treatment of lumbar instability. In cases of anterior column failure, such as in isthmic spondylolisthesis, supplemental posterior lumbar interbody fusion (PLIF) may improve the fusion rate and endurance of the construct. Posterior lumbar interbody fusion is, however, a more demanding procedure and increases costs and risks of the intervention. The advantages of this technique must, therefore, be weighed against those of a simple posterior lumbar fusion. Methods. Thirty-five consecutive patients underwent pedicle screw fixation for isthmic spondylolisthesis. In 18 patients posterior lumbar fusion was performed, and in 17 patients PLIF was added. Clinical, economic, functional, and radiographic data were assessed to determine differences in clinical and functional results and biomechanical properties. At 2-year follow-up examination, the correction of subluxation, disc height, and foraminal area were maintained in the group in which a PLIF procedure was performed, but not in the posterolateral fusion—only group (p < 0.05). Nevertheless, no statistical intergroup differences were demonstrated in terms of neurological improvement (p = 1), economic (p = 0.43), or functional (p = 0.95) outcome, nor in terms of fusion rate (p = 0.49). Conclusions. The authors' findings support the view that an interbody fusion confers superior mechanical strength to the spinal construct; when posterolateral fusion is the sole intervention, progressive loss of the extreme correction can be expected. Such mechanical insufficiency, however, did not influence clinical outcome.

GAW proposes a new approach for the detection and measurement of the Cherenkov light produced by GeV/TeV gamma rays traversing the Earth atmosphere which imposes specific requirements on the electronics design. The focal surface of the GAW telescope consists of a matrix of multi-anode photomultipliers. The large number of active channels (of the order of 10^5) makes it basically a large UV sensitive digital camera with high resolution imaging capability. The limited amount of space available, due to the large number of channels, requires a compact design with minimal distance between the elements of the focal surface. The front-end electronics uses the single photoelectron counting technique to capture the Cherenkov light. The data acquisition is based on free-running data taking method. Self-triggering capability for each telescope is assured by detecting an excess of active pixels, in a 10ns time frame, inside overlapping trigger areas covering the whole focal surface. In this paper we describe the GAW electronics, as well as the trigger concept and implementation., 30th International Cosmic Ray Conference, Merida, Mexico