Minimum Cost Design of Cellular Networks in Rural Areas with UAVs, Optical Rings, Solar Panels and Batteries

Bringing the cellular connectivity in rural zones is a big challenge, due to the large installation costs that are incurred when a legacy cellular network based on fixed Base Stations (BSs) is deployed. To tackle this aspect, we consider an alternative architecture composed of UAV-based BSs to provide cellular coverage, ground sites to connect the UAVs with the rest of the network, Solar Panels (SPs) and batteries to recharge the UAVs and to power the ground sites, and a ring of optical fiber links to connect the installed sites. We then target the minimization of the installation costs for the considered UAV-based cellular architecture, by taking into account the constraints of UAVs coverage, SPs energy consumption, levels of the batteries and the deployment of the optical ring. After providing the problem formulation, we derive an innovative methodology to ensure that a single ring of installed optical fibers is deployed. Moreover, we propose a new algorithm, called DIARIZE, to practically tackle the problem. Our results, obtained over a set of representative rural scenarios, show that DIARIZE performs very close to the optimal solution, and in general outperforms a reference design based on fixed BSs

Primary carcinoid tumour of the common bile duct

Background Carcinoid tumours of the extrahepatic biliary tree are exceedingly rare. We report a case of primary carcinoid tumour arising in the distal portion of the common bile duct. Case outline A 30-year-old man was admitted with watery diarrhoea and symptoms of biliary obstruction. Abdominal ultrasound scan showed a normal gallbladder without stones, mild dilatation of the intra- and extrahepatic biliary tree and a 2 cm solid lesion in the head of pancreas compressing the distal common bile duct. Computed tomography confirmed these findings and showed that the tumour was hypervascular. Gastrointestinal hormone screening showed an increase in plasma serotonin. The patient underwent a standard pylorus-preserving proximal pancreatoduodenectomy (PPPD). Results Pathological examination showed a neuroendocrine tumour (carcinoid) of the distal bile duct. The postoperative plasma serotonin decreased to normal levels. One year later the patient is well without evidence of disease. Discussion Primary carcinoid tumours of the extrahepatic biliary tree are rare, accounting for 0.2–2% of all digestive carcinoids. This is the fifth report of a tumour arising from the distal common bile duct. Surgical treatment for neoplasms of the distal common bile duct can be problematic because of the site of the lesion and the difficulty in differentiating them from periampullary neoplasms lesions. Pancreatoduodenectomy (PD) is therefore the treatment of choice

Neurofibromatosis type 1 associated with systemic vasculopathy

Systemic vasculopathy in patients with neurofibromatosis type 1 is rare. We describe a case of unusual cerebral and renal involvement in a young, 29-year-old patient, who died of a cerebral ischemic attack one year after our observation

Interferometric Missions: Applications within ASI Space Programs

The Italian Space Agency (ASI), together with Ministry of Defence (I-AD), is involved in the realization of the COSMO-Skymed program that foresees the deployment of a constellation of 4 SAR satellites in Low Earth Orbit, dedicated to the management, control and exploitation of Earth resources for civilian and defence applications. ASI is responsible for the definition, implementation and management of the Program, while Alcatel Alenia Space Italia is the Prime Contractor responsible for the design, development and verification of the entire system. The nominal phasing of the satellites on the orbit plane has been selected in order to achieve the optimisation of the performance in terms of accessibility and revisit time w.r.t. the number of satellites. Moreover COSMO-SkyMed system is able to perform interferometric acquisitions, which yield three dimensional images and/or provide various information on land conformation change, subsidence, land-slides and so on. Then, periodically, one of the four satellites will be moved to a fixed distance with respect to another for reaching the interferometric configuration. In order to increase the operating capacity of the COSMO-Skymed system, ASI intends to start the definition of a complementary civilian program with the purpose of covering bi-static and across-track/along-across interferometry applications. Such a mission will be referred as “SABRINA”, acronym of “System for Advanced Bistatic and Radar INterferometry Applications”, based on the use of a “passive” satellite (“BISSAT”, acronym for “Bistatic and Interferometric SAR SATellite”). This satellite will fly in formation with COSMO-Skymed and then a suitable strategy shall be determined for reaching and maintaining the interferometric configuration. The paper will describe the manoeuvre strategies necessary for reaching the interferometric configuration, both for COSMO-Skymed and for BISSAT. Such strategies have been defined taking into account all the constraints coming from the satellite (Δv size, minimum interval time between two consecutive manoeuvres, propulsion S/S performance, AOC requirements). After the description of the manoeuvres requested for achieving the interferometric configurations foreseen for COSMO-Skymed (tandem and “tandem-like”), the paper will focus on the configuration requested for the BISSAT satellite for flying in formation with a single COSMO-SkyMed satellite. Two formation configurations will be selected: pendulum or cartwheel. The mission will carry out interferometric acquisitions in the following configurations: 1. Across track interferometry 2. Along track interferometry The mission will carry out bistatic acquisition multi-angle and multi-polarization with a baseline variable in the range 100-500 km

Capillaroscopy: a new application for the evaluation of vascular side-effects induced by chemotherapy

Background: Cancer survivors are rising up, but this better survival is accompanied by possible treatments side-effects. In particular, cardiovascular effects are commonly reported, even if vascular damage is not necessarily connected to clinical manifestations. Periungual microcyrcle evaluation through capillaroscopy could identify asymptomatic patients with high risk of cerebro-cardio- vascular disease. The aim of this pivotal study is to evaluate videocapillaroscopy in patients who undergo chemotherapy, in order to understand if it could represent in future a prognostic tool to predict the risk of cardio-cerebro-vascular events. Methods: We conducted an open-label, uncontrolled study. Patients affected by solid tumors were enrolled. Each subject underwent a clinical evaluation and a videocapillaroscopic examination. Results: We selected 25 patients. Mean age was 55.48 years. Time interval between the start of chemotherapy and capillaroscopy: average 41 months. From our analysis it emerges that ectasia and hemorrhages could be a possible markers of capillary insult caused by chemotherapy. Conclusions: Our study shows the presence of capillaroscopic features that may be peculiar in chemotherapy-induced endothelial damage. The individuation of capillaroscopic alteration specific for chemotherapy-induced endothelial injury could be an important tool to identify patients with high cardiovascular risk

Lifetime-aware ISP networks. Optimal formulation and solutions

We propose a framework to manage the link lifetime in an IP backbone network by exploiting the sleep mode (SM). In particular, when an SM feature is available, two different effects coexist: 1) during the SM state, the lifetime tends to be increased and 2) however, when the link changes its power state (from SM to full power or vice-versa), the lifetime tends to be decreased. We, therefore, define an optimal formulation of the lifetime-aware network problem. Moreover, we propose a heuristic, called Acceleration Factor Algorithm, to practically manage the device lifetime. We solve the problem both optimally and with our heuristic, considering two representative case studies. Results show that our approach outperforms the previous energy-aware algorithms, which instead do not consider the lifetime decrease triggered by the power state change. Thus, we argue that a lifetime-aware network management should be pursued when deciding to set an SM state for each device in an Internet Service Provider network

The soilmodels.info project

The paper describes the soilmodel.info project to disseminate constitutive models among FE codes' users