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The growing interest in Unmanned Aerial Systems has led, especially in recent years, to the need for a precise structure of rules and procedures aimed to guarantee safe traffic management. As an important type of dynamic data-driven application system, Unmanned Aerial Systems are widely used for civilian, commercial, and military applications across the globe and require a high level of autonomy. Indeed, the absence of the pilot onboard leads to stricter requirements regarding the level of accuracy for the Unmanned Systems, with the need to provide autonomous services such as Conflict Detection and Resolution during the strategic and tactical phases, avoiding possible collisions. In order to explore efficient and robust solutions for autonomous Collision Avoidance, an increasing research effort has been devoted to Trajectory Prediction for non-cooperative UASs. In this work, an analysis of existent solutions for Trajectory Prediction has been evaluated, with particular emphasis on methods based on Machine Learning (ML). Besides, four different Machine Learning methods based on Regression (Linear Regression, Regression Tree, Gaussian Process Regression, and Support Vector Machine for Regression) have been implemented for the prediction of the flight times of a single drone over planned paths. The four regression methods are used as benchmark for a proposed Deep Learning based approach, and the results have been compared.

Carotid endarterectomy plays an important role in the prevention of ischemic stroke; patching could reduce the risk of intra- and postoperative complications and late restenosis among primary closure. Materials actually available for the patch tailoring are synthetic or biological: which is the best is still debated. We present the case of a polyurethane (PU) carotid patch rejection three years after its implant, with no evident arterial discontinuity and no sign of infection. Histopathological analysis on hematoxylin-eosin stained sections of the regenerated arterial wall tissue removed revealed plasma cell infiltration and clusters of foreign body giant cells. PU patch rejection has been seldom described in literature. This is an unusual late complication that should be considered at long-term follow-up evaluation of these patients.

Arterial vasa vasorum (VV) are known to be involved in the atherosclerotic process. The aim of the present study was to explore whether ultrasound imaging with contrast agent is able to visualize adventitial VV in human carotid atherosclerosis. We studied with standard ultrasound 25 patients with carotid stenosis > 50% (ATS group) and 15 patients without carotid artery plaques and an intima-media thickness (IMT) < 1.0 mm (CTRL group). All patients underwent contrast ultrasound to evaluate periadventitial VV and B-flow imaging (BFI) modality was used to improve and measure periadventitial flow signal. On contrast-enhanced images, a fast microbubble flow and a homogeneous and linear periadventitial contrast signal using BFI were detectable in the adventitial area in all patients of both groups. Periadventitial signal thickness by BFI was higher in patients with atherosclerosis than in the control group (mean +/- SD: CTRL 0.80 +/- 0.06 mm; ATS 1.10 +/- 0.11 mm; P < 0.001). Moreover, considering the whole study population, the adventitial signal thickness significantly correlated with IMT values (r= 0.88, r(2)= 0.77; P < 0.0001). Periadventitial contrast signal was detected in all patients and BFI thickness was higher in patient with carotid atherosclerosis and correlated with IMT.

Angioedema is a localized swelling of sudden onset, often associated with angiotensin-converting enzyme (ACE) inhibitor use, that most commonly occurs in the face and neck. We present the case of a patient on long-term ACE inhibitor therapy for hypertension, who developed postoperative angioedema after carotid endarterectomy (CEA). The patient was initially misdiagnosed with an expanding cervical hematoma and underwent a surgical wound reexploration. Angioedema is a rare cause of neck swelling and upper airway distress occurring after CEA in patients treated with ACE inhibitors and should be considered in the differential diagnosis.

Hand and wrist aneurysms are a rare pathology, but recently the number of cases is increasing because of iatrogenic injuries such as catheter placement for endovascular procedures, invasive blood pressure monitoring, and arterial blood collection. In the period between January 1992 and January 2005, seven patients were treated at our institution for hand and wrist aneurysms. Five were true aneurysms and two were false aneurysms. All patients underwent surgery: four had aneurysmectomy and ligation of the arterial stumps and three had lesion removal, with arterial break suture in two cases and reconstruction with interposition of reversed autologous vein in the other case. In all cases, we did not have any postoperative ischemic or neurological complications. Symptoms like pain, paresthesia, and disesthesia combined with the minimal morbidity associated with repair suggest that operative repair of these aneurysms should be routinely performed.