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On July 15 2000 the first MITA (Italian Advanced Technology Minisatellite) was launched from Plesetsk (Russia) by a Cosmos rocket as a secondary payload with the CHAMP satellite. The main purpose of the first MITA mission is its in-flight validation, since MITA is going to be used as standard platform for small missions. Furthermore the scientific payload NINA-2 of INFN (Istituto Nazionale di Fisica Nucleare) and the technological payload MTS-AOMS (Micro Tech Sensor for Attitude and Orbit Measurement System) were embarked. The NINA-2 goal is the survey of galactic and solar cosmic rays at 450 km altitude. MTS is an ESA multi-tasking autonomous sensor based on Active Pixel Sensor (star and horizon sensor), Angular Rate Sensor and Magnetic Field Sensor. In this paper the main MITA bus characteristics are reported, together with the description of the launch and the commissioning phase. The first mission nominal orbit is circular, with a 450 Km altitude and a 87.3° inclination. The satellite attitude is nadir pointing, 3 axes stabilised. Spacecraft mass is 169.9 Kg. Two fixed solar panels provide an average power of 85 W EOL. The configuration of the satellite main body is based on a cubic shape module, made of Aluminium beams and honeycomb panels. This paper will start with a brief description of the MITA standard bus, followed by the presentation of its in-orbit results and performances, while a second part of the text will introduce the two new implementative missions of the bus i.e., AGILE, a Gamma Ray astronomical observatory and HypSEO, an Earth Observation demonstrating mission supporting an Hyperspectral Camera.

BACKGROUND: The aim of this study was to evaluate the incidence and management of complications of videosurgical procedures that occurred during a 4-year period in eight Italian pediatric surgery centers. METHODS: Between 1996 and 1999, 2305 videosurgical procedures were performed in 11 centers of pediatric surgery. The data from 3 centers, for a total of 616 procedures, were largely incomplete and were thus excluded from the study. We analyzed the data from 8 centers only, for a total of 1689 laparoscopic or thoracoscopic operations on patients aged between 15 days and 16 years. The type of operations performed ranged from basic videosurgical interventions, such as varicocelectomy and cryptorchidism, to advanced laparoscopic procedures, such as splenectomy, total colectomy, and esophageal achalasia. Each patient's file was examined for any complications that may have occurred during the surgical procedure and for a record of how these were managed. RESULTS: We recorded 79 complications (4.6%) in our series. In 57 cases (72.2%) the problem was solved by videosurgery. Twenty-two cases (27.8%) required conversion to open surgery. There was no mortality in our series. At a maximum follow-up of 4 years, all children were alive and had no problems related to the videosurgical complications. CONCLUSIONS: We believe that the routine use of open laparoscopy in pediatric patients is a key factor to avoiding complications related to the Veress needle and blind introduction of the first trocar. Moreover, the surgeon's laparoscopic experience, the correct indications for laparoscopic surgery, and the verification of the laparoscopic equipment before surgery are also important rules to follow to reduce the incidence of complications. In the beginning, it is preferable to have the assistance of an expert laparoscopic surgeon to decrease the complications related to the learning curve period.

After the decision taken by the ESA Council in 1995 concerning the European participation to the International Space Station (ISS), the user disciplines involved (Microgravity, Space Science, Earth Observation and Technology) are now called to consolidate the strategy for its utilization. The technology user community has high expectations for the utilization of the Space Station: key technologies that would benefit from being validated in-orbit can rely upon frequent access to the Station, considerable in orbit resources, and long duration exposure to the space environment. Early flight opportunities for European payloads are available from 1999 for pressurized experiments, and from 2001 for unpressurized experiments. The European module launched in 2002 will mark the beginning of the routine utilization phase lasting until 2013. To prepare the utilization of the Space Station, the Agency has established a preliminary utilization plan covering the full utilization period of the Space Station. This plan contains the following major pillars: “Early Opportunities”, “COF Utilisation Preparation”, and “Promotion”. The paper presents the key features of the ESA utilization plan from a general standpoint. Particular emphasis is given on the Technology utilization plans and selection procedure.

The paper describes the main results available from the EURECA post flight technology investigations. Emphasis is given to findings that can be used to improve flux model simulation tools used to design spacecraft. Flux models are commonly used by designers for example to estimate the material erosion by atomic Oxygen and the risk of collision of the spacecraft with micrometeoroids or debris. The paper illustrates how the impact features and degradation effects recorded on Eureca can be used to verify and improve the prediction accuracy of the flux simulation tools.

The EUropean REtrievable CArrier (EURECA) and one of the Hubble Space Telescope (HST) solar arrays were returned from space in 1993 after, respectively, 11 months and 3.62 years in Earth orbit. ESA has initiated post-flight investigation programmes which include recording and analysis of impact features on all exposed EURECA surfaces (total area ≈ 140 m 2 ) and on the Hubble solar array (total area ≈ 60 m 2 ). The impact analysis plan, measurements for EURECA and model predictions for the Hubble array are presented.

Introduction Advances in laparoscopy determinates very important modifications in the treatment of Hirschsprung disease. The aim of this study is analyse the results, of four different centres, in the treatment of Hirschsprung disease, according to Georgeson’s primary laparoscopic pull-through. Materials and Methods In the last 4 years 74 cases of HD, in four different centres of pediatric surgery, were submitted to primary laparoscopic pull-through (LPT) according to Georgeson’s technique. The age ranged between 20 days and 15 years. All were investigated by rectal suction biopsy, barium enema and anorectal manometry. No diverting colostomy was performed and the patients were managed with pre-operative bowel nursing. Surgery required 3 operative ports as described by Georgeson. The colon was examined and several biopsies were performed at different proximal levels to precisely define the normoganglionic colon. Surgery was postponed after the results of the intraoperative histochemical studies. The definitive diagnosis were: 27 ultra short segment (US), 37 recto sigmoid segment (RS), 6 long segment (LS), 1 total colonic aganglia (CA) and 3 rectosigmoid segment associated to IND extended to the left flexure. The mesocolon was divided using ligasure, bipolar or monopolar hook. After the transanal dissection was completed, the videoassisted pull-through was carried out making attention to the placement of the pedicle and of the sieromuscular cuff. The operative time ranged from 180’ and 540’. Results There were 2 conversions to open technique, while in 1 case a postoperative colostomy;no addictional intraoperative complication was found. The patients had analgesics for 24 hours. Bowel movements were observed at 24- 48 hours, the oral feeding started after 48 hours, the median hospital stay was 7 days. At follow-up 3 patients had grade I enterocolitis in the fìrst months; 2 cases of LS and one case of RS had about 4 toilets/day. In one case of US soiling was present for 5 months postoperatively. Conclusion The laparoscopic pulll-through is a safe operation for almost ali cases of HD. It allow to obtain several biopsies necessary to define the precise diagnosis of the disease and to perform a correct surgery. Moreover the laparoscopy permits to avoid the torsion of the vascular pedicle during the trans anal pull-through.

The numerical study presented in this paper aims at assessing the role played by different aspects on the resistance of bolted joints in shear. To this purpose, a simplified procedure is proposed, based on rigid-plastic limit analysis, used in conjunction with a specifically devised finite element, essentially “plane” but accounting for the effects of transverse strain components. Results show that the model, although resting on drastic simplifying assumptions, permits a better understanding on the influence of a few important aspects affecting the overall joint behavior, such as the role of transverse plastic deformations, the restraining effect of the nut and the contact between the bolt and the metal plate. In particular, it explains how the nut and the washer have a fundamental role in bearing resistance of bolted connections and why pin design requires a different approach.