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An increasing number of robotic hysterectomies are being performed and the most common indication is fibroids. Fibroid uterus is common indication for hysterectomy for enlarged uteri. The role of robotic approach for complex pathologies as enlarged uterus is still debatable. The study aimed to analyze the feasibility of robotic hysterectomy in patients with enlarged uteri and the impact of uterine weight on surgical outcomes and on operative time length.One hundred and thirty-eight patients who underwent robotic hysterectomy for benign indications at the 2nd Division of Obstetrics and Gynecology, Azienda Ospedaliero-Universitaria Pisana, University of Pisa were consecutively enrolled.Data of patients undergoing robotic surgery for benign indications were collected. Patients were stratified in two groups based on their uterine weight, to analyze the effective impact of uterine weight and dimension on surgical performance, operative time and postoperative outcomes. Conversion rate was 0%. Median uterine weight was 615 g (range 400-1900 g). Median total operating time was 131 minutes (range 70-255 minutes). Increase in uterine weight significantly increased operative times (p=0.003) and morcellation time (p=0.001). On the other hand, operative time was just partially influenced by route for removal of the uterus (p=0.085) but significantly affected by uterine weight (p=0.008), previous surgeries (p=0.003) and BMI of the patient (p=0.005).Robotic hysterectomy is feasible and safe for challenging cases as large uteri. This technique could enable patients with outsized uteri, not suitable for vaginal hysterectomy, to undergo minimally invasive surgery with excellent results. Larger studies to investigate and compare robotic with other surgical approaches for difficult hysterectomies are needed to confirm these data.

The establishment and spread of Non-Indigenous Species (NIS) can be facilitated through perturbations that lower the resilience of native communities to invasion. After a disturbance to a rocky subtidal macroalgal assemblage in the Mediterranean Sea (Italy) by a shipwreck (Costa Concordia), we compared native and non-native seaweed community structure at the disturbed site and two reference sites using traditional abundance measures, in addition to employment of the ALien Biotic IndEX (ALEX). ALEX has been recently proposed as a potential multi-metric indicator to evaluate biological invasions in Mediterranean macroalgal assemblages, taking into account both the relative abundance of macroalgal NIS to native seaweed abundances and the invasive traits of those NIS. We found that macroalgal NIS were initially more abundant at the disturbed site, but four months later were decreased and there were no difference with the reference sites. Native macroalgal cover at the disturbed site was lower than at reference sites in the initial survey, but unexpectedly decreased significantly four months later. Despite the decline in the cover of macroalgal NIS, ALEX was consistently lower through time at the disturbed site, due to concurrent declines in native seaweed abundances. This suggests that evaluation of macroalgal NIS should not be based on cover of macroalgal NIS alone and that the relative cover of native species should also be considered. ALEX may represent a versatile tool to be employed in both monitoring programs and impact evaluation studies.

Volcanoes subjected to hydrothermal activity develop weak cores as a result of alteration and due to elevated pore pressures. Edifices constructed at the angle of repose of volcanoclastics, or at even more gentle slopes, respond to internal weakening by initially deforming slowly, but may then collapse catastrophically. Such a process has so far been described for only a few volcanoes, such as Casita, Nicaragua; however, the conditions for flank spreading are widespread and many, if not most volcanoes should suffer some alteration-related flank spreading. We provide analogue models that characterise the structure — surface deformation fields and internal structures — of a spreading flank. Deformation creates a characteristic concave-convex-concave flank profile producing structures such as basal thrusts, summit normal faults, grabens and strike-slip relay faults. Three deformation regimes are found: a ‘pit collapse’ regime is associated with very small volumes of ductile material located far from the edifice surface. This would not appear in nature, as time for deformation is greater than the lifetime of a volcano, unless very low rock viscosities are present. The other two regimes are flank spreading regimes, one symmetric and one asymmetric. The latter is the most common, as most volcanic structures are asymmetrical in form and in distribution of physical properties. The deformation is controlled by altered region dimensions, volume and position relative to the edifice, and to a lesser extent by its shape. As the flanks spread, landslides are created, initially on the steepened portion, but also from fault scarps. Major flank collapse may occur leading to explosive hydrothermal decompression and to a debris avalanche rich in hydrothermally altered material. We provide several new examples of volcanoes that have structures and morphologies compatible with flank spreading. We suggest that it is a common feature, important in the tectonics and hazards of many volcanoes.

We present a method of reconstructing volcanic morphology using multiple digital views ( N -view), captured at different angles around an object. This approach uses recent advances in the field of Computer Vision to provide accurate 3-D measurements of volcanic surfaces. Videogrammetry (digital image reconstruction) is used, as it is best adapted to numerical processing. The method is tested and now used in the laboratory on analogue volcanic cones. The method begins with calibrating the camera and finding image positions, using an accurate N -view calibration method. This is done by estimating internal and external parameters of the camera using several views of a specially constructed calibration target. The N -view reconstruction of the real object is then done by iteratively deforming an initial theoretical model of the surface. Laboratory tests show that reconstruction accuracy is about 10 −4 m for a distance between the object and the camera of 0.5 m, and is potentially several orders of magnitude higher for surfaces of finer texture and using higher precision sensors. This is easily high enough to be useful for the accuracy required for morphological studies. It is also sufficient for monitoring most types of volcano deformation. The technique has the potential to detect morphology changes of the order of mm. Use of the method in the field requires a slightly different approach from that in the laboratory: textures and lighting are more variable, and the sensor and ground control point location and model calibration must be done differently. We provide case studies from laboratory tests and qualitative image analysis for two field cases: Piton de la Fournaise (Indian Ocean) and Santaguito (Guatemala). These illustrate the technique’s potential and explore problems of field application. Using current sensors, the method has the potential to provide sufficient precision for fine (mm–cm) scale reconstruction, and will represent a valuable, simple and flexible tool when compared with classical stereophotogrammetry techniques.