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Space Surveillance and Tracking (SST) is growing more and more important in the Space operations and mission analysis field, given how much the crowded environment building up near Earth can hamper them. Italy is involved in SST operations, collaborating with partners both within and outside the EU. The Italian Space Operation Centre (ISOC) has recently upgraded its systems to the ISOC 2.0 Suite, an integrated web-based platform providing multiple functions and services in the SST/SSA domain. The present work describes its sensor tasking module, called SNOS (Sensors Network Optimal Scheduler), developed thanks to a collaboration involving the Italian Air Force, the Leonardo Company and Politecnico di Milano. After the definition of the software architecture, its prototype version has been developed in Python and then translated to C++ language to grant the highest performances in the operational environment. Given the list of available sensors together with their characteristics, the time window in which the observations must be scheduled and the catalogue of objects to be observed, SNOS is able to generate a user specified number of schedules, optimized both in terms of catalogue coverage and expected quality of the measurements. The results are provided to the sensor operation authority as a JSON file conveying all the information needed for the correct execution of the task and as a Tracking Data Message (TDM), which is the Consultative Committee for Space Data Systems (CCSDS) standard for this kind of operations. SNOS can handle optical sensors as well as mono- or bi-static radar and laser sensors. The process starts from the analysis of Two Line Elements (TLE) or Orbit Ephemeris Message (OEM) representing the state of the catalogued objects to identify the visible passes, i.e. the portions of their orbits which are visible from any of the sensors of the network. These are subdivided based on the priority assigned to the related object and conflicting situations are identified, such as the ones in which multiple passes from different objects are simultaneously visible by the same sensor. The candidate solutions are then gradually built by selecting passes (or portions of them) with a heuristic optimization approach. The generated schedules are assigned a score based on the catalogue coverage and the expected quality of the measurements, which weights factors such as the elevation of the object, the distance from the observer, and the duration of the pass. The scheduler also grants the possibility to modify an already ongoing schedule to allocate tasks for unforeseen necessities highlighted by the sensor authority, while still retaining the optimality of the solution. Finally, SNOS can compute the necessary sensor pointing sequence for different kind of tasks, namely tracking tasks and various survey modes of practical interest, such as the one for the surveillance of the GEO belt and the ones designed for the identification of new debris through the inspection of areas along the orbit of an object which is expected to have suffered fragmentation. The SNOS software is currently successfully employed to run the network managed by the ISOC centre.

Navicular bone fractures of the foot are rare , but can have serious consequences because of the essential role of the talonavicular joint. A classification system was devised on the basis of the direction of the fracture line, the pattern of disruption of the surrounding joints, and the direction of displacement of the foot.

In this study, the effects of bicarbonate addition on growth and pigment contents of the unicellular microalga Nannochloropsis oculata, were evaluated. N. oculata represents an interesting source of biomolecules widely used for food supplements and nutraceuticals. The bicarbonate was supplemented to microalgae cultures at concentrations of 0, 6, 18, 30, 42 and 60 mM. The cultures supplemented with salt at highest concentrations (42 and 60 mM) showed a significant increase in algal growth, demonstrated by the optical density spread. The intracellular content of pigments such as chlorophyll a and total carotenoids reached the highest values in cells from cultures supplied with bicarbonate. In fact, concentrations of bicarbonate from 30 to 60 mM strongly improved, for a short period of only 72 h, the cellular levels of chlorophylls and carotenoids. These are interesting pigments with commercial applications. The utilization of bicarbonate could represent an interesting sustainable opportunity to improve microalgae cultivation for cellular growth and pigment contents.

The incidence of neuroendocrine tumors (NETs) is progressively increasing. Most cases arise from the digestive system, where ileum, rectum and pancreas represent the commonest site of origin. Liver metastases are frequently detected at diagnosis or during the follow-up. Contrast-enhanced ultrasound (CEUS) is used in patients with pancreatic NETs (P-NETs) and liver metastases from P-NET but its role has not been standardized. The aim of this retrospective study was to investigate CEUS in patients with P-NETs and liver metastases from P-NET both as prognostic factor and predictor of response to therapy with somatostatin analogues (SSAs). CEUS was performed at the diagnosis of NET and 3, 6 and 12 months after the beginning of SSAs. CEUS pattern was compared with contrast-enhanced computed tomography (CT) pattern. There was a significant association between CEUS and CT pattern (X 2 = 79.0; p

The possibility of using the sperm of teleosts as a model system for ecotoxicological assessments has been explored by evaluating sperm motility parameters: (1) time to reach the maximum motility value (activation time), (2) maximum motility value, (3) duration of maximum motility value, and (4) total time of motility (until class 0). Sperm of Dicentrarchus labrax, Sparus aurata, Diplodus puntazzo and Pagellus erythrinus were analysed and compared. The effects of dimethylsulfoxide, ethylene glycol, propylene glycol, glycerol and methanol on sperm motility in these marine species were investigated. Among the systems tested, sperms of S. aurata and D. labrax were the most sensitive to the tested xenobiotics and S. aurata spermatozoa were shown to be easier to manage for ecotoxicological assays.