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Launched in April 1996, operational for six years, BeppoSAX has opened a new view on the X-ray universe, with its broad-band and wide angle instruments associated with flexible ground segment operations. In this paper we recall some of the history behind the development of the project, summarize some of its scientific achievements and comment on its heritage.

During the period from 1974 to June 2000 we used the straight ileo-anal Soave pull-through to treat 42 patients (24 affected by total colonic aganglionosis [TCA], 10 with ulcerative colitis and 8 with familial polyposis). The aim of this paper is to show that this operation, associated with total colectomy, is highly recommended, causing a lower number of complications when compared to the various "reservoir" techniques. The mean age of the 24 patients with TCA at the time of the pull-through was 2.8 years; in the ulcerative colitis group, it was 14.3 years and in the familial polyposis group 27.2 years. We always used an ileo-anal deferred anastomosis and never performed temporary loop-diverting ileostomy at the time of the pull-through. In the TCA patients we had no immediate or long-term serious post-operative complications: ileal adaptation, after a frequency of 10 - 12 liquid stools a day, showed a gradual, constant and in some cases amazing improvement in all children. Two years after surgery, the mean stool frequency was 3.6 per 24 hours with no significant differences between the 3 main groups; only 4 children still presented with occasional soiling. After pull-through, all children showed normal growth curves in the long term. There was no malabsorption, no serious electrolyte imbalance, no perianal excoriation, no strictures or intestinal obstruction; their quality of life was considered more than satisfactory by the children's families. We have no direct experience with the various ileal "reservoir" techniques for ulcerative colitis and ileal polyposis nor with colon-sparing operations for TCA; as reported in the literature, all these surgical procedures seem to have a higher number of complications such as pelvic sepsis, pouchitis, enterocolitis, etc. compared with our series; we therefore confirm that total colectomy with the straight ileo-anal Soave pull-through is our treatment of choice, as it is simpler to perform and has fewer short- and long-term complications.

A description is given of the X-ray facility installed at LAX (Laboratorio per Sperimentazioni con Radiazioni X), jointly operated in Palermo by the DEAF (Department of Energy and Physics Applications) of the University of Palermo and the IFCAT (Institute of Cosmic Physics and Informatics) of the Italian National Research Council. The X-rays are produced by bombarding a target with energized electrons up to 60 keV. Depending on the material of the target, characteristic fluorescence lines as well as continuous bremsstrahlung is emitted. The X-ray beam has an operational energy range of 0,1–25 keV with a flux of 1010–1012 photons/sr · s; the beam, collimated on a length of 10,5 m, has a diameter at full aperture of 200 mm with a divergence of 1°. The beam line consists of: the X-ray generator the Beam Channel the Sample Chamber with a table capable of translation along the X, Y and Z axes and rotation around Y and Z the Detector Chamber with translation movements along the X and Y axes and rotation around Y. The X-ray generator chamber operates at 10−9 hPa, whereas the other parts operate at 10−6 hPa. The beam line has been developed by RIAL Vacuum S.p.A. following the specifications of DEAF and IFCAI. Der Artikel beschreibt die Rontgenstrahlungsanlage am LAX (Labor fur Experimente mit Rontgenstrahlung) in Palermo, die gemeinsam vom DEAF (Fakultat fur Energie und angewandte Physik) der Universitat Palermo und dem IFCAI (Institut fur kosmische Physik und Informatik) der nationalen italienischen Forschungsgemeinschaft betrieben wird. Die Rontgenstrahlung wird durch Beschus eines Targets mit beschleunigten Elektronen (bis 60 keV Energie) erzeugt. Je nach Targetmaterial werden dabei sowohl charakteristische Fluoreszenzlinien als auch ein kontinuierliches Bremsstrahlungsspektrum emittiert. Der Rontgenstrahl hat im Energiebereich 0,1–25 keV einen Flus von 1010–1012 Photonen/sr · s. Der Strahl wird uber eine Lange von 10,5 m kollimiert und hat bei voller Offnung von 200 mm eine Divergenz von 1°. Die Anlage besteht aus folgenden Teilen: Kammer fur die Rontgenquelle, Strahlrohr, Probenkammer mit einem Verschiebetisch, der Translationen entlang der x-, y- und z-Achsen und Drehungen um die y- und z-Achsen erlaubt, Nachweiskammer mit Verschiebevorrichtung entlang der x- und y-Achsen und Drehung um die y-Achse. Die Kammer fur die Rontgenquelle arbeitet bei einem Druck von 10−9 hPa, die restlichen Anlagenteile bei 10−6 hPa. Die Anlage wurde von RIAL Vacuum S.p.A. nach den Vorgaben von DEAF und IFCAI entwickelt.

In this paper we discuss the feasibility of a ground based detector exploiting the technique of Cerenkov light stereo imaging of air showers for the detection of discrete cosmic sources of γ-rays with energy threshold of 100 GeV, angular resolution (HWHM) of 1 arcmin ( 1 3 mrad), cosmic ray background rejection ≥ 99%. This experiment will make possible a deep survey of the sky with sensitivity of 1 100 of the Crab in 45 h of exposure.

We present a new γ-ray telescope based on the Limited Streamer Tube technology, used as tracking chambers to detect photons above 100 MeV. This technique allows to obtain very large sensitive areas (16 m2 in our experiment), together with a good angular resolution for payloads embarcable in high-altitude balloon flights. The capability to collect a large signal in a short exposure time makes the telescope particularly suitable and competitive with respect to satellite-based detectors for studying both periodic and random time variabilities on galactic and extragalactic γ-ray sources.

We describe a method of analysis for the reconstruction of the arrival direction of a high-energy photon impacting on the top of the atmosphere by using the directions of the particles on the shower front as measured by a ground-based array of tracking chambers uniformly distributed on a square surface; as an example, an array with enclosed surface of (120×120) m2 has been considered. Estimates on the accuracy of reconstruction are given, after application of the method to computer-simulated shower directions as a function of the number of «smapling» detectors and of their accuracy in the measurement of the «local» shower direction.

SAX (X-Ray Astronomy Satellite) is a programme jointly developed by the Italian Space Agency (A.S.I.) and the Netherland Agency for Aerospace Programmes (NIVR) devoted to systematic, integrated and comprehensive studies of galactic and extragalactic sources in the energy band 0.1 – 200 KeV.

Background/Purpose: Vesico-ureteric reflux (VUR) is a common problem in children with neuropathic bladder. Lesserdegree VUR may be manageable by intermittent catheterization or by anticholinergics, but higher grades usually require surgical treatment. If left untreated, two thirds of such patients may experience deterioration of the upper renal tracts. The aim of this study was to compare the results of the STING (Subureteric Teflon Injection) technique with surgical ureteric reimplantation as treatment for VUR in neuropathic bladder. Methods: From January 1981 to December 1996, 58 children with NB (81 ureters) were treated for VUR. STING and Cohen ureteroneocystotomy were performed in 40 and 41 ureters, respectively. Mean age was 4.5 years (STING) and 5.1 years (Cohen). Results: Twenty-nine of 40 refluxing ureters (72.5%) were cured by STING, whereas Cohen eradicated reflux in 39 of 41 ureters (95.5%). No complications were observed in either group. All the ureters in which STING failed were treated successfully by Cohen ureteroneocystostomy. The 2 ureters still refluxing after surgical reimplantation were cured successfully by a single STING. The mean follow-up was 6.8 years in the Cohen group and 4.8 years in the STING group. During follow-up, no recurrence was observed in patients cured by open reimplantation. In the STING group, 2 previously cured ureters showed recurrence of VUR: both were treated successfully by a further STING. Conclusions: Open ureteral reimplantation is more effective than STING in correcting VUR in children with neuropathic bladder dysfunction. Nevertheless, the good success rate, the relative technical simplicity, outpatient nature, and rapid recovery point to STING as a safe and effective procedure for the initial treatment of VUR. Failure of STING does not preclude a successful open operation.

Within the AIRWATCH collaboration, we propose to measure the Earth night side background with high accuracy using the UVSTAR instrument from the Shuttle.

The satellite for X-ray astronomy SAX, to be launched at the end of 1993, is devoted to systematic, integrated and comprehensive, studies of galactic and extra-galactic sources in the energy band 0.1–200 keV, and is under joint development by the Italian Space Agency (ASI) and the Netherlands Agency for Aerospace programs (NIVR), with the participation of SRU/SRON and SSD/ESTEC. The basic scientific objectives can be summarized as follows:– Broad band spectroscopy (E/Δ E=12) from 0.1–10 keV with imaging resolution of 1 arcmin.– Continuum and line spectroscopy (E/Δ E=5–20) in the energy range 3–200 keV.– Variability studies of bright source energy spectra on timescales from milliseconds to days and months.– Systematic long term variability studies over the entire sky down to a source intensity of 1 mCrab.

The Joint European X-Ray Telescope, JET-X, is one of the core instruments of the scientific payload of the USSR SPECTRUM-X astrophysics mission due for launch in 1993. The JET-X instrument concept is described and its scientific performance and capability discussed.

The longitudinal development and other characteristics of the EECR induced atmospheric showers can be studied from space by detecting the fluorescence light induced in the atmospheric nitrogen. According to the Airwatch concept a single fast detector can be used for measuring both intensity and time development of the streak of fluorescence light produced by the atmospheric shower induced by an EECR. In the present communication the detection capabilities for the EECR observation from space are discussed., Comment: 3 pages (LaTeX). To appear in the Proceedings of TAUP'97

We explore the possibility of gaining suitable vesical capacity and continence in bilateral single ureters without having to resort to urinary diversion or bladder neck reconstruction.In the last 10 years we treated 6 girls with bilateral ectopic ureters, and 2 with a single kidney and urethral ectopic ureter. Both ureters were ectopic in the urethra in 3 cases, and 1 ureter was inserted in the urethra and 1 in the bladder neck in the other 3. Preoperative examinations included ultrasonography, cystography, excretory urography and endoscopy in all cases, and magnetic resonance imaging in 2. Patient age at intervention ranged from 1 month to 8 years.Cross-trigonal reimplantation of the ectopic ureters through a correctly positioned neomeatus was performed in 7 cases. In 2 patients it was impossible to reach the ureteral insertion from inside the bladder (1 ureter in 1 and both ureters in 1), and so the distal tract of these ureters was resected extravesically as close as possible to the urethra. One patient with a single kidney also had an anorectal malformation and a rectovaginal fistula. She had pelvic renal ectopia and the ureter was inserted beneath the urogenital diaphragm causing minimal bladder capacity. Therefore, a sigmoid neobladder with appendicostomy was constructed according to the Mitrofanoff principle. A Young-Dees bladder neck plasty was done in 2 patients at the same time as ureteral reimplantation and 3 years later in 1. Followup urodynamics revealed more than acceptable continence. Bladder capacity was insufficient in only 1 polyuric patient.A bladder with bilateral ureteral ectopia is not necessarily useless, and the majority of patients can achieve normal bladder function and capacity along with normal transurethral voiding and satisfactory continence.

Il programma AirWatch riguarda l'osservazione dallo spazio degli sciami estesi di particelle prodotti nell'atmosfera da particelle cosmiche di altissima energia. Nell'ambito di tale programma si colloca il progetto EUSO, recentemente sottoposto all'ESA da una collaborazione internazionale. In questa nota si descrivono la problematica scientifica connessa con i raggi cosmici di altissima energia, le problematiche tecniche legate all'osservazione dallo spazio degli sciami atmosferici estesi e si descrivono le linee di una possibile partecipazione dell'INFN al programma AirWatch ed al progetto EUSO in particolare.

BeppoSAX, the X-Ray Astronomy satellite operating in the (0.1–300) keY energy band has now lived more than 30.000 hours in orbit and it is halfway to complete the 3rd round of observations (A03 started at the beginning of may 1999 and it will end in April 2000). A report is given on the general fields covered by the mission and on the more relevant results obtained. The satellite is in excellent operating conditions and it is foreseen to continue the observational life-time well beyond the initially scheduled 3 years.

The Cosmic Radiation, with its charged and neutral components, can be considered the second fundamental channel for the investigation of the Universe complementing the “Electromagnetic” specific of the conventional Astronomy. The experimental approach considered here is based on the observation from a Low Orbit Satellite of the UV fluorescence signal produced in the Earth atmosphere by the incoming radiation. A general description is given of the AIR WATCH/OWL experiment; some detail will also be given of “EUSO”: Extreme Universe Space Observatory” a proposal which is being submitted to the European Space Agency in response to an Announcement of Opportunity (AO) issued on October 1999.

A novel experimental installation is described in which the traditional method of detecting extensive air showers with scintillation counters is significantly extended by the addition of limited streamer tube hodoscopes (LST) and layers of resistive plate counters (RPC). Runs with the scintillator array, GREX, at Haverah Park have demonstrated the power of the LST hodoscopes to determine the direction of arrival of muons, electrons and photons in air showers while the RPC system permits the relative arrival time of individual particles and the temporal thickness and structure of the shower disc to be obtained. The potential of these technical advances for studying the longitudinal profile of air showers produced by primaries of about 1000 TeV is briefly discussed. First measurements of thickness and time profile of EAS front are also reported.

The authors present their experience about intra-abdominal lymphangiomas and mesenteric cysts. The histologic evidence shows that these lesions are different. An exact histologic diagnosis is important because lymphangiomas are more invasive and relapsing than mesenteric cysts. Of 8 cases founded at laparotomy, 6 were lymphangiomas and 2 mesenteric cysts. Larger lesions were caused by lymphangiomas (mean, 11 cm vs 6 cm) when compared with mesenteric cysts. Complete resection was possible in all 8 patients, without recurrence after a mean follow-up of 4 years.

The Authors present ten cases of sacro-coccygeal teratomas observed during the last ten years at the G. Gaslini Children Institute, Genova. Two cases was diagnosed in the pre-natal period. Diagnostic methods, histologic aspect and surgical treatments are discussed.

In the framework of past and near-future X-ray missions the SAX satellite, to be launched at the end of 1995, stands out for its very wide spectral coverage, from 0.1 to 200 keV. Here we briefly describe the perspectives offered by the wide band capability of SAX. More details on the scientific objectives, instrument performances, and operations can be found elsewhere (e.g. Butler and Scarsi 1990; Perola 1990; Piro 1992 and references therein).

The possibility of performing neutrino astronomy by means of a detector above the ground depends critically on the feasibility of a rejection power on the order of 10 11 required to discriminate the enormous background of cosmic downward going muons from the signal of upward going muons produced by neutrinos. In order to check whether and how this rejection is obtainable, we have built in the Physics Department of the University of Bari a horizontal cosmic muon telescope (MINI) instrumented with resistive plate counters. By performing time-of-flight measurements, we have estimated the rejection power of our telescope for left and right coming cosmic muons. The rejection dependence on a few fundamental parameters like minimum number of points per track, telescope length, RPC time resolution and on trigger configuration has been investigated.

Vesico-ureteral reflux (VUR) is a relatively frequent and severe complication in neuropathic bladder, therefore it must be ruled out in every case, and prevented whenever possible. The Spina Bifida Center of our Institute is presently following 220 patients with neuropathic bladder, who undergo a periodical clinical and instrumental evaluation. Urodynamics has proved essential in detecting risk factors for VUR: small capacity bladders with reduced compliance, increased outlet resistance, and detrusor instability. Forty-eight cases of VUR, 38 of which were severe, were detected in a total of 166 patients reviewed for this paper. All patients with VUR were treated conservatively, attaining complete remission or improvement in 21 cases. Ten underwent surgical treatment owing to recurrent pyelonephritis or pyelo-renal reflux with severe dilatation, despite a standard pharmacological trial.

During the third flight of the FIGARO II experiment on July 9th 1990 the Crab pulsar PSR0531+21 has been kept in the axis of the telescope during 7.5 hours.On line analysis showed the pulsar light curve with only 5 minutes of data acquisition time.The complete analysis of the observation will probably help to search for gamma ray line in the pulsed part of the spectrum.Particularly a line around 450 keV has been previously detected by some experiments but at low statistical level and attributed ambiguously to the Nebula.

SAX (X-Ray Astronomy Satellite) is a programme jointly developed by the Italian Space Agency (A.S.I.) and the Netherland Agency for Aerospace Programmes (NIVR) devoted to systematic, integrated and comprehensive studies of galactic and extragalactic sources in the energy band 0.1 – 200 KeV.

The satellite for X-ray astronomy SAX, to be launched at the end of 1993, is devoted to systematic, integrated and comprehensive, studies of galactic and extra-galactic sources in the energy band 0.1–200 keV, and is under joint development by the Italian Space Agency (ASI) and the Netherlands Agency for Aerospace programs (NIVR), with the participation of SRU/SRON and SSD/ESTEC. The basic scientific objectives can be summarized as follows: — Broad band spectroscopy (E/△ E=12) from 0.1–10 keV with imaging resolution of 1 arcmin. — Continuum and line spectroscopy (E/△ E=5-20) in the energy range 3–200 keV. — Variability studies of bright source energy spectra on timescales from milliseconds to days and months. — Systematic long term variability studies over the entire sky down to a source intensity of 1 mCrab.

Les donnees du telescope Cerenov de Potchefstroom, du satellite COS B et du telescope Compton MPE sont analysees pour detecter la presence d'un signal de rayonnement gamma en direction du pulsar binaire a eclipse PSR 1957+20. Une emission Rγ possible au point lagrangien L 4 est determinee pour deux des trois ensembles de donnees.

The paper describes a non-parametric analysis to obtain the phase histogram of a pulsar as seen in the satellite reference frame; the method requires only an approximate knowledge a priori of the pulsar period and of the position of the satellite. Results are presented on the derivation of the X-ray (2–12 keV) and gamma-ray ( E >50 MeV) pulsar phase histograms relative to NP-0532 as observed by the COS-B satellite.

When we talk of Gamma-Ray Astronomy we refer in general to celestial photons covering the energy domain from a fraction of MeV up to the highest detected energies at hundreds or thousands of GeV. The six to seven decades altogether spanning the overall energy range constitute a very wide domain to be compared with those of the optical (less than one decade) or of the neighbouring X-Ray Astronomy (about two decades). The observational technique varies widely with changing energy; detector performances and characteristic parameters are not, in general, comparable.