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The identification of recent major tectonic structures in the Galicia continental margin and adjacent abyssal plains was carried out by means of a quantitative analysis of the linear structures having bathymetric expression on the seabed. It was possible to identify about 5800 lineaments throughout the entire study area, of approximately 271,500 km2. Most lineaments are located in the Charcot and Coruña highs, in the western sector of the Galicia Bank, in the area of the Marginal Platforms and in the northern sector of the margin. Analysis of the lineament orientations shows a predominant NE-SW direction and three relative maximum directions: NW-SE, E-W and N-S. The total length of the lineaments identified is over 44,000 km, with a mode around 5000 m and an average length of about 7800 m. In light of different tectonic studies undertaken in the northwestern margin of the Iberian Peninsula, we establish that the lineaments obtained from analysis of the digital bathymetric model of the Galicia continental margin and adjacent abyssal plains would correspond to fracture systems. In general, the orientation of lineaments corresponds to main faults, tectonic structures following the directions of ancient faults that resulted from late stages of the Variscan orogeny and Mesozoic extension phases related to Triassic rifting and Upper Jurassic to Early Cretaceous opening of the North Atlantic Ocean. The N-S convergence between Eurasian and African plates since Palaeogene times until the Miocene, and NW-SE convergence from Neogene to present, reactivated the Variscan and Mesozoic fault systems and related physiography. [ABSTRACT FROM AUTHOR]

Deception Island shows the most recent exposed active volcanism in the northern boundary of the Bransfield Trough. The succession of the volcanic sequence in the island is broadly divided into pre- and post-caldera collapse units although a well-constrained chronological identification of the well-defined successive volcanic episodes is still needed. A new paleomagnetic investigation was carried out on 157 samples grouped in 20 sites from the volcanic deposits of Deception Island (South Shetlands archipelago, Antarctic Peninsula region) distributed in: (1) volcanic breccia (3 sites) and lavas (2 sites) prior to the caldera collapse; (2) lavas emplaced after the caldera collapse (10 sites); and (3) dikes cutting pre- and the lowermost post-caldera collapse units (5 sites). The information revealed by paleomagnetism provides new data about the evolution of the multi-episodic volcanic edifice of this Quaternary volcano, suggesting that the present-day position of the volcanic materials is close to their original emplacement position. The new data have been combined with previous paleomagnetic results in order to tentatively propose an age when comparing the paleomagnetic data with a global geomagnetic model. Despite the uncertainties in the use of averaged paleomagnetic data per volcanic units, the new data in combination with tephra occurrences noted elsewhere in the region suggest that the pre-caldera units (F1 and F2) erupted before 12,000 year BC, the caldera collapse took place at about 8300 year BC, and post-caldera units S1 and S2 are younger than 2000 year BC. [ABSTRACT FROM AUTHOR]

Purpose: Kidney transplantation is the preferred treatment for patients with end-stage renal disease. In order to reduce the morbidity of the open surgery, a robotic-assisted approach has been recently introduced. According to the published literature, the robotic surgery allows the performance of kidney transplantation under optimal operative conditions while maintaining the safety and the functional results of the open approach. Methods: We present the case of a mother donating to her daughter affected by end-stage renal disease (ESRD) due to Alport disease (creatinine: 353 umol/l; GFR: 13 ml/min per 1.73 m). Results: A robotic-assisted kidney transplant (RAKT) was successfully performed. Surgical time was 120 min with 53 min for vascular suture. The estimated blood loss was <50 cc. The kidney started to produce urine intra-operatively with a rate of 250 cc/h, which remained constant over the next hours. During the first postoperative day, the patient was ambulating and started oral intake. Pain was minimal, and no analgesia was required after 48 h. Serum creatinine improved progressively to 89 umol/l on postoperative day 3. No surgical complications were recorded, and the patient was sent home on postoperative day 5. Conclusion: We present the first Spanish transperitoneal pure RAKT from a living-related donor. We believe this is the second pure robotic-assisted kidney transplantation case performed in Europe. We believe that the potential advantages of RAKT are related to the quality of the vascular anastomosis, the possible lower complication rate and the shorter recovery of the recipients. [ABSTRACT FROM AUTHOR]

Elephant Island, located in the vicinity of the present-day active boundary of the South Shetland Block and the Antarctic and Scotia plates, is a region of particular interest for understanding the past and present geodynamic evolution of the southern Scotia Arc. Lineament from different data sources, field-measured fractures and geomorphological evidences have been analysed in this context. The lineaments extracted from aerial photographs (1,624), from a DEM (348) and from RADARSAT-2 satellite data (1,365) indicate four dominant lineament sets with NE-SW, NW-SE, N-S and W-E strikes. All data sources identified similar lineament families, but differences in the frequency distributions and subsequently on the dominant orientations were observed. The measurements direct of fractures were obtained from 23 sites in the field at which 278 planes were measured. Fracture planes indicate main modes trending in the NNE-SSW and NNW-SSE directions and a secondary mode in the E-W. The major trends of the fracture measurements and the lineaments display a good correlation in the E-W direction. However, there is an angular variation in the azimuth values of the NNE-SSE and NNW-SSE fractures with respect to the N-S, NE-SW and NW-SE orientations of the lineaments of approximately 20°. This trend deviation may be due to the fact that mapped lineaments are composed of small fracture sets that may be related to shear fractures that cannot be distinguished at the aerial photograph or radar satellite data scales. Submerged sea-floor morphological feature orientations match the studied morphostructures on the island and the main tectonic structures in this part of the Scotia Arc. A linkage of the main lineament families to the tectonic stages from the Oligocene to the present has been proposed, taking into account the information of the orientation and sense of movement of the fractures and stresses in the Elephant Island region. [ABSTRACT FROM AUTHOR]

Traditional methods of image restoration use only one observed image for processing. In this paper, we propose methods for image restoration using several distorted images obtained with a microscanning imaging system. We assume that the observed images contain an original image degraded either by additive or by multiplicative interferences. Additionally, the images are corrupted with the additive noise of a receiver sensor. Using a set of observed images, image restoration is carried out by solving a system of equations that is derived from optimization of an objective function. Since the proposed restoration methods possess a high computational complexity, a fast algorithm is proposed. Computer simulation results obtained with the proposed methods are analyzed in terms of restoration accuracy, tolerance to the additive input noise, and robustness to sensors'position errors. [ABSTRACT FROM AUTHOR]

Common restoration techniques use a single observed image for the processing. In this work three observed degraded images obtained from camera microscanning are utilized for image restoration. It is assumed that the degraded images contain information about an original image, multiplicative interference, and additive sensor’s noise. Using captured images a set of linear or nonlinear equations and objective function are formed. By solving the system of equations with the help of an iterative algorithm, the original image can be recovered. A fast algorithm for approximated image restoration is proposed. Computer simulations results presented and discussed. [ABSTRACT FROM AUTHOR]