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Synthetic aperture radar (SAR) remote sensing is very attractive for the systematic observation of dynamic processes on the Earth’s surface since it allows high resolution imaging independent of weather conditions and sunlight illumination. Waveform-encoded SAR is a novel SAR concept based on pulse-to-pulse variation of the transmitted waveform that allows focusing the nadir echo and the range ambiguities and suppressing them through a multi-focus post-processing. However, the assessment of the ambiguity suppression performance for such a system is not trivial, as the processing involves a non-linear thresholding and blanking approach. This work proposes a novel methodology, which exploits real TerraSAR-X data to accurately simulate the effect of the range ambiguity on the useful signal and allows for a quantitative assessment of the image quality of a waveform-encoded SAR. The analysis considers different waveform variation schemes (namely up- and down-chirps and cyclically shifted chirps) and a contrast-minimization technique for threshold selection, whose performance is compared to the best achievable one (i.e., the optimum threshold). The results of this work further highlight the potentialities of the waveform-encoded SAR concept and allow accounting for its ambiguity suppression capability in the design of a SAR system.

Lesions of the colon are generally considered to be sequelae of pancreatitis. They include: localized paralytic ileus (colon cutoff sign), necrosis, fistulae, stenosis and varices. On the basis of an extensive review of the literature (332 cases), it is suggested that the real incidence of these lesions is significant. The anatomic relationship of the large bowel to the pancreas is an important factor in the genesis and localization of the lesions. Enzymatic-inflammatory and ischemic processes are involved in the most highly supported theories. Each complication shows different diagnostic and clinical patterns. In this paper, six cases of such lesions are presented, including 2 cases of necrosis, 2 of stenosis, 1 of fistula and 1 case of localized paralytic ileus.

We describe the reference software architecture of parIDL, a PSE for distributed memory parallel computers that integrates the parallel software library ScaLAPACK, needed to develop and test scientific applications related to adaptive optics simulations. It incorporates a run time support for the execution of the commercial problem solving environment IDL on parallel machines, whose development has begun in a project with astronomy researchers for adaptive optic simulation of terrestrial large binocular telescopes.

The Authors report the incidence of local relapsing in a group of 362 patients who underwent Patey's mastectomy from 1974 to 1985. The overall incidence was 9.6%. The predictive factors of major value were: presence of lymph node metastases, primary tumor size and grading.

Although breast metastases are not frequent, the most common ones are from cutaneous melanoma. In this paper two cases of breast metastases from malignant melanoma are reported. The literature is reviewed and the diagnostic and therapeutic problems related to metastatic mammary neoplasms are analyzed.