Evaluation of the TOPSAR performance by using passive and active calibrators

The preliminary analysis of the C-band cross-track interferometric data (XTI) acquired during the MAC Europe 1991 campaign over the Matera test site, in Southern Italy is presented. Twenty three passive calibrators (Corner Reflector, CR) and 3 active calibrators (Active Radar Calibrator, ARC) were deployed over an area characterized by homogeneous background. Contemporaneously to the flight, a ground truth data collection campaign was carried out. The research activity was focused on the development of motion compensation algorithms, in order to improve the height measurement accuracy of the TOPSAR system

Long-term follow-up of elderly patients with operable breast cancer treated with surgery without axillary dissection plus adjuvant tamoxifen.

Between 1982 and 1990, 321 elderly patients (range 70-92 years, median age 77) with operable breast cancer (T1 in 219, T2 in 77, T3 in one and T4b in 24 patients) and clinically uninvolved axillary nodes underwent surgery without axillary dissection and received adjuvant tamoxifen. All patients had surgery performed under local anaesthesia. Tamoxifen was given after surgery at the dose of 20 mg daily, indefinitely. With a median follow-up of 67 months (range 42-141), 17 patients developed local relapse, 14 ipsilateral axillary recurrence, five ipsilateral breast cancer, five contralateral breast cancer, 13 second primary and 23 developed distant metastases. The cumulative probability of developing a local, axillary and distant recurrence at 72 months was estimated to be 5.4%, 4.3% and 6.2%, respectively. Out of 244 patients who did not develop any relapse, 83 (25.8%) died from intercurrent disease. The 72 month relapse-free survival rate was 76%. This experience suggests that elderly patients with small tumours without clinical axillary involvement may be satisfactorily treated with conservative surgery and tamoxifen. The importance of axillary dissection is controversial owing to a high response rate to hormonal therapy and an increased death rate due to concomitant diseases

Experimental results from a stepped frequency GPR

In the framework of a nationally funded project, a Ground Penetrating Radar (GPR) has been developed by the Italian Consortium for Research on Advanced Remote Sensing Systems (CO.RI.S.T.A.). The system was described in a previous paper (Alberti et al., 2002). As new aspects, the system is a stepped frequency GPR that can work both in gated and ungated mode, and the antennas can be moved automatically in a controlled fashion. As aspects of geophysical interest, the system is exploitable in situations wherein a high resolution and a shallow penetration in the soil (a few meters) are required. Possibly, this is an example of probing a landscape. This paper completes the results of Alberti et al. (2002), wherein laboratory tests where described, by providing the main results obtained during an outdoor experimental campaign, performed fi rst in a controlled site and then in an archaeological site

Titan's diverse landscapes as evidenced by Cassini RADAR's third and fourth looks at Titan

International audienceCassini's third and fourth radar flybys, T7 and T8, covered diverse terrains in the high southern and equatorial latitudes, respectively. The T7 synthetic aperture radar (SAR) swath is somewhat more straightforward to understand in terms of a progressive poleward descent from a high, dissected, and partly hilly terrain down to a low flat plain with embayments and deposits suggestive of the past or even current presence of hydrocarbon liquids. The T8 swath is dominated by dunes likely made of organic solids, but also contain somewhat enigmatic, probably tectonic, features that may be partly buried or degraded by erosion or relaxation in a thin crust. The dark areas in T7 show no dune morphology, unlike the dark areas in T8, but are radiometrically warm like the dunes. The Huygens landing site lies on the edge of the T8 swath; correlation of the radar and Huygens DISR images allows accurate determination of its coordinates, and indicates that to the north of the landing site sit two large longitudinal dunes. Indeed, had the Huygens probe trajectory been just 10 km north of where it actually was, images of large sand dunes would have been returned in place of the fluvially dissected terrain actually seen?illustrating the strong diversity of Titan's landscapes even at local scales