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Sal ‘e Porcus is the largest natural salt flat in Europe, located in Sardinia (Italy) in the southwest region of the Mediterranean area. It spans over an area of more than 3.3 square kilometers. Its homogeneity and size characteristics make it a potentially suitable spot for use as a satellite sensor calibration/validation site. For this purpose, a campaign of spectral, mineralogical and LiDAR data acquisition has been organized in the framework of a dedicated International Remote Sensing Summer School in 2023. Furthermore, the study of this site has been funded by the Italian Spatial Agency through the Project: System for the “COnsOlidation of L2 products from the PRISMA-SG mission (COOL)”.New orbiting hyperspectral sensors such as ASI-PRISMA and EnMAP DLR and near future continuity missions (ASI-PRISMA SG, ESA CHIME) request ground reflectance spectra to rely on the remote sensed data. In this study, the first results of the study of the spectral and LiDAR data acquired on the site are described and discussed, focusing on two main outputs: i) the first release of the spectral library of the minerals of the salt flat; ii) the morphological setting of the surface.The collection of the spectra has been coupled with sediment samples for mineralogical characterization. During these campaigns, UAV-based LiDAR data were acquired. First results show that the topography of the surface changes from west to east, giving the idea of a geological control of this flat area. Moreover, first results of the spectral characterization of this surface using field, UAV and satellite data are discussed.

Naples is the most densely populated Italian city (7744 inhabitants per km2). It is located in a particular geological context: the presence of Mt Vesuvius characterizes the eastern part, and the western part is characterized by the presence of the Phlegrean Fields, making Naples a high-geothermal-gradient region. This endogenous heat, combined with the anthropogenic heat due to intense urbanization, has defined Naples as an ideal location for Surface Urban Heat Island (SUHI) analysis. SUHI analysis was effectuated by acquiring the Land Surface Temperature (LST) over Naples municipality by processing Landsat 8 (L8) Thermal Infrared Sensor (TIRS) images in the 2013–2023 time series by employing Google Earth Engine (GEE). In GEE, two different approaches have been followed to analyze thermal images, starting from the Statistical Mono Window (SMW) algorithm, which computes the LST based on the brightness temperature (Tb), the emissivity value, and the atmospheric correction coefficients. The first one is used for the LST retrieval from daytime images; here, the emissivity component is derived using, firstly, the Normalized Difference Vegetation Index (NDVI) and then the Vegetation Cover Method (VCM), defining the Land Surface Emissivity (LSɛ), which considers solar radiation as the main source of energy. The second approach is used for the LST retrieval from nighttime images, where the emissivity is directly estimated from the Advance Spaceborne Thermal Emission Radiometer database (ASTER-GED), as, during nighttime without solar radiation, the main source of energy is the energy emitted by the Earth’s surface. From these two different algorithms, 123 usable daytime and nighttime LST images were downloaded from GEE and analyzed in Quantum GIS (QGIS). The results show that the SUHI is more concentrated in the eastern part, characterized by intense urbanization, as shown by the Corine Land Cover (CLC). At the same time, lower SUHI intensity is detected in the western part, defined by the Land Cover (LC) vegetated class. Also, in the analysis, we highlighted 40 spots (10 hotspots and 10 coldspots, both for daytime and nighttime collection) that present positive or negative temperature peaks for all the time series. Due to the huge amount of data, this work considered only the five representative spots that were most representative for SUHI analysis and determination of thermal anomalies in the urban environment.

Urban surfaces play a crucial role in shaping the Urban Heat Island (UHI) effect by absorbing and retaining significant solar radiation. This paper explores the potential of high-resolution satellite imagery as an alternative method for characterizing urban surfaces to support UHI mitigation strategies in urban redevelopment plans. We utilized Landsat images spanning the past 40 years to analyze trends in Land Surface Temperature (LST). Additionally, WorldView-3 (WV3) imagery was acquired for surface characterization, and the results were compared with ground truth measurements using the ASD FieldSpec 4 spectroradiometer. Our findings revealed a strong correlation between satellite-derived surface reflectance and ground truth measurements across various urban surfaces, with Root Mean Square Error (RMSE) values ranging from 0.01 to 0.14. Optimal characterization was observed for surfaces such as bituminous membranes and parking with cobblestones (RMSE < 0.03), although higher RMSE values were noted for tiled roofs, likely due to aging effects. Regarding surface albedo, the differences between satellite-derived data and ground measurements consistently remained below 12% for all surfaces, with the lowest values observed in high heat-absorbing surfaces like bituminous membranes. Despite challenges on certain surfaces, our study highlights the reliability of satellite-derived data for urban surface characterization, thus providing valuable support for UHI mitigation efforts.

Abstract Background To evaluate feasibility, safety and effectiveness of transarterial embolization of acute non-neurologic hemorrhage with Ethylene Vynil Alcohol Copolymer (EVOH). Methods Between January 2018 and June 2021, 211 patients (male 123, mean age 69.7 y + 17.9) who underwent transarterial embolization with Onyx™ for acute non-neurologic arterial bleeding were retrospectively reviewed. Most frequent etiology of bleeding was post-operative (89/211, 42.2%), trauma (62/211, 29.4%) and tumor (18/211, 8.5%). Technical success was defined as the angiographic evidence of target vessel complete occlusion. Clinical success was defined as resolution of bleeding. Any rebleeding within the primitive site, requiring a new intervention during the first 30-days following embolization, was considered a clinical failure. Occurrence of procedure-related complication and mortality within 30 days of the embolization were examined. Results A total of 229 embolization procedures was performed in 211 pts.; technical success rate was 99.5% (210/211 pts). Clinical success rate was 94.3% (199/211 pts). In 11 patients (5.2%) a reintervention was needed because of a rebleeding occurring within the primitive site, whereas in five patients (2.4%) rebleeding occurred within a site different from the primitive. Factors more often associated with clinical failure were coagulopathy/ongoing anticoagulant therapy (5/11, 45.4%), and post-operative etiology (3/11, 27.3%). EVOH was used as the sole embolic agent in 214/229 procedures (93.4%), in association with coils in 11 cases (4.8%), and with microparticles in 4 cases (1.7%). In the present series, major complications occurred in 6 cases (2.8%): respectively, four cases (1.9%) of colonic ischemia and two groin hematomas (0.9%) with active extravasation were observed. 26 (12.3%) patients died during the follow-up. Conclusion Embolization of acute arterial bleeding with EVOH as a first-line embolic agent is feasible, safe and effective.

The measurement of volcanic gases, such as CO2 and SO2, emitted from summit craters and fumaroles is crucial to monitor volcanic activity, providing estimations of gases fluxes, and geochemical information that helps to assess the status and the risk level of an active volcano. During high degassing events, the measurement of volcanic emissions is a dangerous task that cannot be performed using hand portable or backpack carried gas analysis systems. Measurements of gases plumes could be safety achieved by using instruments mounted on UAS (Unmanned Aerial System). In this work, we present the measurements of CO2, SO2, and H2S gases collected with a miniaturized MultiGAS instrument during 2021 and 2022 field campaigns. They took place at several thermally active areas in Italy: Pisciarelli (Naples, Italy), Stromboli volcano (Messina, Italy), and Parco Naturalistico delle Biancane (Grosseto, Italy).

Abstract Background Flow-diverter stents (FDS) are designed to maintain laminar flow in the parent artery and sidebranches and to promote thrombosis of the aneurysm. Although these devices were developed for use in intracranial circulation, FDS could be employed to treat aneurysms regardless of their location, when anatomic factors may limit the efficacy of classic endovascular techniques. The objective of this study is to describe the initial experience of a single center in the treatment of visceral artery aneurysms and pseudoaneurysms (VAA-VAP) with cerebral FDS, analyzing safety, efficacy and 1-year outcome. Between 2016 and 2018 six patients (4 women, mean age 57.6) underwent treatment with FDS of 4 VAA and 2 VAP located in renal (4), hepatic (1) and splenic arteries (1). Mean aneurysm diameter was 14.3 mm (range 8–22). All the aneurysms had sidebranches arising from the neck or had an unfavorable dome-to-neck ratio. Technical success, safety, efficacy and 1-year outcome were analyzed. Follow-ups (FU) with Color-Doppler US and CTA ranged from 12 to 36 (mean 20) months. Results Technical success was achieved in all cases. There were no aneurysm rupture nor reperfusion after exclusion. Five out of six (83.3%) FDS were patent at each FU; all the aneurysms showed shrinkage with a mean dimensional reduction rate of 55.8%. Sac thrombosis was observed in 4 aneurysms at 1 (n = 3) and at 12-month FUs. There was one sidebranch occlusion with evidence of a small area of kidney hypoperfusion at the 12-month FU, which was asymptomatic. In one patient, a reintervention was needed because CTA showed a severe in-stent stenosis, which was symptomatic. Mean hospitalization was 4.1 days. Conclusions Treatment of morphologically complex VAA and VAP with cerebral FDS proved to be safe and efficient. Stronger evidence from larger populations are required.

Vulcano belongs to the seven volcanic islands forming the Aeolian archipelago (Italy) and has the privilege to define an eruptive style as “Vulcanian”. It has to be considered as an active volcano as its most recent activity demonstrated. Starting by late spring 2021, the thermal state of the Vulcano summit area changed and the gas emission increased. During the summer and, in particular, starting from September, geophysical and geochemical signals, precisely those linked to the activity of the hydrothermal system that feeds the fumaroles of the Fossa crater, varied. The temperature of the gases emitted by the fumaroles on the crater rim has increased and the composition of the gases has showed an increase in CO2 and SO2 (carbon dioxide and sulfur dioxide) concentration. For such reasons, the authors decided to follow this event by analyzing the remotely sensed available data suitable for detecting changes in thermal state. By processing the TIRS (Landsat 8) and ASTER time series, two long-term surface temperature logs were obtained and, therefore, by adopting a statistical approach, an analysis in both space and time domains has emphasized a thermal signature since mid-September 2021.

Surface temperatures derived by 208 ASTER and L8 satellite imagery were analysed to test multiscale and multitemporal capability through available sets of thermal data to support the volcanic monitoring of Vulcano Island in Italy. The analysis of thermal historical series derived by ASTER and L8 shows that two are the main thermally active areas: La Fossa crater and the mud pool of Fangaia. In this work we aimed to assess the correlation between the satellite-retrieved temperatures with those measured during the daytime ground field campaign conducted within the same time period and, in particular cases, simultaneously. Moreover, nighttime data acquired by an airborne and field campaign were processed with the same methodology applied to satellite data for a multiscale approach verification. Historical meteorological data acquired from a weather station were also considered. Statistically significant correlations were observed between nighttime acquisitions and meteorological data. Correlations were also significant for temperature measured during the airborne campaign, while differences up to 50% with daytime acquisition during the ground field campaigns were observed. The analysis of the results suggests that within nighttime data acquisition, differences between satellite-derived temperatures and ground temperature measurements are considerably reduced; therefore nighttime data acquisition is recommended to detect thermal anomalies.

OBJECTIVE: This is a retrospective study on Pharmacomechanical Catheter- Directed Thrombolysis (PCDT) in the treatment of acute iliofemoral Deep Vein Thrombosis (DVT). PATIENTS AND METHODS: From March 2013 to November 2016, 22 patients (26 limbs), median age 46.7 years with acute (<21 days) extensive iliofemoral DVT underwent Percutaneous Mechanical Thrombectomy (PMT) with Aspirex (Straub Medical, Wangs, Switzerland), followed by Catheter- Directed Thrombolysis (CDT). Subsequent endovascular stenting was performed for underlying obstruction. The follow-ups were conducted up to 1 year, in two Centers by experienced operators. Post-Thrombotic Syndrome (PTS) was evaluated by assessing the Villalta Scale (VS) and measuring orthostatic venous pressure. RESULTS: Post-operative iliofemoral vein patency was restored in almost all cases (95.5%). Standard urokinase dose was 80.000 IU per hour; mean infusion time was 32.5 hours. Stenting was performed in 15 cases (68%). Median follow-up was 19.9 months (6-48 months); 21/22 patients completed the 12 months follow-up. At 30 days follow-up symptoms disappeared in 21/22 cases (95.5%), with one case (4.5%) of DVT recurrence. At 1-year follow- up there were 3 cases (14.2%) of mild PTS; 18 patients (85.8%) were free from PTS. At 1-year follow-up venous pressure measurement showed normal values in 11 cases (52.4%), mild hypertension in 7 patients (33.3%), moderate hypertension (80-100 mmHg) in 2 cases (9.5%) and severe hypertension (110 mmHg) in one case (4.8%). Neither major nor minor complications were observed. CONCLUSIONS: PMT with Aspirex combined with CDT with urokinase seems to be a safe and effective treatment for acute iliofemoral DVT and it shows promising results in reducing the risk of PTS. Thus, we suggest a controlled trial with this treatment strategy. [ABSTRACT FROM AUTHOR]

How to deliver data to, or collect data from the hundreds of thousands of sensors and actuators integrated in “things” spread across virtually every smart city streets (garbage cans, storm drains, advertising panels, etc.)? The answer to the question is neither straightforward nor unique, given the scale of the issue, the lack of a single administrative entity for such tiny devices (arguably run by a multiplicity of distinct and independent service providers), and the cost and power concerns that their direct connectivity to the cellular network might pose. This paper posits that one possible alternative consists in connecting such devices to their data collection gateways using “oblivious data mules”, namely transport fleets such as taxi cabs which (unlike most data mules considered in past work) have no relation whatsoever with the smart city service providers, nor are required to follow any pre-established or optimized path, nor are willing to share their LTE connectivity. We experimentally evaluate data collection and delivery performance using real world traces gathered over a six month period in the city of Rome. Results suggest that even relatively small fleets, such as an average of about 120 vehicles, operating in parallel in a very large and irregular city such as Rome, can achieve an 80% coverage of the downtown area in less than 24 h. [ABSTRACT FROM AUTHOR]

Many vehicular ad-hoc network protocols have been validated using complex urban mobility simulators or by means of the few publicly available real mobility traces. This work presents an extensive measurement campaign of the positions of a fleet of 370 taxi cabs moving around the city of Rome, Italy. Due to its street network and its traffic conditions, Rome presents a characteristic mobility pattern representative of an ancient city with heavy road congestion, and therefor provides a valuable test case to experiment VANET protocols. We exploit these traces to run a set of experiments to assess the performance of a simple epidemic protocol that we compare with the basic random waypoint model in order to quantify how far the performance metrics are from this baseline. The results show the possible outcomes of implementing data dissemination through an opportunistic network that uses taxi cabs as an information vector. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to review the use of an hourglass-shaped expanded polytetrafluoroethylene (ePTFE) stent-graft to reduce transjugular intrahepatic portosystemic shunts in patients with hepatic encephalopathy refractory to conventional medical therapy., Materials and Methods: From January 2000 through December 2008, 189 transjugular intrahepatic portosystemic shunt procedures were performed with self-expanding stent-grafts. After a mean period of 43.4 +/- 57 weeks, hepatic encephalopathy developed in 12 patients and did not respond to conventional medical therapy with lactulose, nonabsorbable antibiotics, and a protein-restricted diet. In all cases, shunt reduction was performed with an hourglass-shaped balloon-expandable ePTFE stent-graft inserted into the original shunt., Results: Technically successful shunt reduction with an immediate increase in portosystemic gradient was achieved in all patients. Symptoms of hepatic encephalopathy disappeared a mean of 22.3 hours (range, 18-26 hours) after the procedure. After a mean follow-up period of 73.9 +/- 61.88 weeks, no recurrence of hepatic encephalopathy was found. One patient (8.3%) needed dilation of the hourglass-shaped stent-graft after 37 weeks because of recurrence of ascites. At the end of the study, five patients (41.6%) were alive in good clinical condition. Four patients (33.3%) died of cardiovascular failure 1, 2, 24, and 96 weeks after the corrective procedure. Eight months after the reduction procedure, one patient (8.3%) underwent orthotopic liver transplantation, which resulted in clinical improvement. Two patients (16.6%) were lost to follow-up 15.6 and 46.8 weeks after the procedure., Conclusion: Shunt reduction with an hourglass-shaped ePTFE balloon-expandable stent-graft seems effective in reducing shunt flow and rapidly improving the patient's clinical condition. With this technique, shunt diameter can be modified on the basis of the patient's clinical condition.