324 research outputs found

    Aquatic Macrophytes Occurrence in Mediterranean Farm Ponds: Preliminary Investigations in North-Western Sicily (Italy)

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    Mediterranean wetlands are severely affected by habitat degradation and related loss of biodiversity. In this scenario, the wide number of artificial farm ponds can play a significant role in the biodiversity conservation of aquatic flora. In the present contribution we show the preliminary results of a study on Mediterranean farm ponds of north-western Sicily (Italy), aimed to investigating the environmental factors linked to the occurrence of submerged macrophytes (vascular plants and charophytes). We studied the aquatic flora of 30 ponds and determined the chemical and isotopic composition of their water bodies on a subset of the most representative 10 sites. Results show that (1) farm ponds host few but interesting species, such as Potamogeton pusillus considered threatened at regional level; (2) Chara vulgaris, C. globularis and P. pusillus behave as disturbance-tolerant species, occurring both in nitrates-poor and nitrates-rich waters, whereas Stuckenia pectinata and Zannichellia palustris occur only in nitrates-poor waters. Although farm ponds are artificial and relatively poor habitats, these environments seem to be important for the aquatic flora and for the conservation of the local biodiversity, and can give useful information for the use of macrophytes as ioindicators in the Mediterranean area

    New cost-effective technologies applied to the study of the glacier melting influence on physical and biological processes in Kongsfjorden area (Svalbard)

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    The Arctic region is greatly affected by climate change, with evident alterations in both physical and biological processes: temperatures are changing at a rate that is twice the global average and phytoplankton productivity is directly affected by ice melting. Continuous monitoring of this ecosystem is fundamental to gain greater understanding of the impact of changes on the natural environment, but the Global Ocean Observing System only provides partial coverage in these extreme areas, which are particularly difficult to reach. Technological progress in oceanographic measurement capabilities is indispensable for the implementation of marine observatories, especially in these remote regions. In recent years, autonomous systems and cost-effective technologies have proved to be valuable for increasing spatial and temporal coverage of data. This is the case with the innovative ArLoC (Arctic Low-Cost) probe, which was designed and developed for easy integration into various types of platforms, enabling continuous measurement of temperature, pressure and fluorescence of chlorophyll a. This work reports on the results of two scientific campaigns carried out in Kongsfjorden (Svalbard Islands) in 2018 in the framework of the UVASS (Unmanned Vehicles for Autonomous Sensing and Sampling) research project. The ArLoC probe was integrated onboard the PROTEUS (Portable RObotic TEchnology for Unmanned Surveys) unmanned semi-submersible vehicle and this allowed us to collect important data in the stretches of sea near tidewater glacier fronts. The acquired data showed several significant effects of glacier melting such as: high temperature and salinity gradients, which cause considerable variations in water mass stratification, and an increase in turbidity and the chlorophyll a concentration, which directly affects primary productivity and the trophic chain. During the surveys, ArLoC proved to be an easy-to-integrate, very reliable instrument, which permitted high spatial resolution investigation of ecological processes during glacier melting as never studied before

    MAAT system design – weight model of very large lighter-than-air vehicle

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    Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.The main objective of this paper is to provide a realistic weight model, based on the physical-mathematical foundations, for the design of the new very large lighter-than-air vehicle, called Multibody Advanced Airship for Transport (MAAT), the ongoing European FP7 project, which is currently under intensive research and development activities. The Modeling and Simulation (M&S) principles, aided with simulations and visualization tools, have been extensively used, as the key enablers to combine, manage and structure such highly complex engineering process, which emerged as a natural integration mechanism and evidence provider of the encountered complexity, successfully encompassing the MAAT multidisciplinary design requirements. The authors experience, in solving the M&S problems, gained within the European R&D projects, was efficiently reused, where the use of such software technologies have been successfully demonstrated, and today, further applied for the new generation transportations solutions, as envisaged by MAAT, especially addressing the best practices in taking advantage of the variety of multi-physics software and their related analysis tools. The MAAT system is envisaged to be composed of two airships: the Cruiser, which stays at a constant altitude of 16 km, travelling horizontally; and the Feeder, which acts like an elevator system connecting the Cruiser to the ground. In this paper, the proposed weight model is similar to the typical one applied in the aircraft design process. The main difference is primarily the airship teardrop shape, which is commonly applied for the currently produced airships. The main challenge is that MAAT has a very large shape, which has required the introduction of new elements and references, as being presented in this work. The achieved results show that MAAT can be realized, by taking into account the significant weight estimated for such aircrafts, to be for the Cruiser about 533 tons, while the Feeder weight is about 12 tons. As highlighted before, the MAAT design is still under intensive developments, and thus, it is expected that in the coming years, by taking into account the new emerging technological solutions, the lightening of such aircrafts structure is inevitable. In addition, the authors plans are to further investigate new materials and their related applications, in order to improve the structural part of the MAAT system, as one of the essential parts in such new transportation system, expected to become the reality in the forthcoming future.cf201

    C4BQ0: a genetic marker of familial HCV-related liver cirrhosis.

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    Source Department of Medicine and Pneumology, V Cervello Hospital, Via Trabucco 180, 90146 Palermo, Italy. [email protected] Abstract BACKGROUND AND METHODS: Host may have a role in the evolution of chronic HCV liver disease. We performed two cross-sectional prospective studies to evaluate the prevalence of cirrhosis in first degree relatives of patients with cirrhosis and the role of two major histocompatibility complex class III alleles BF and C4 versus HCV as risk factors for familial clustering. FINDINGS: Ninety-three (18.6%) of 500 patients with cirrhosis had at least one cirrhotic first degree relative as compared to 13 (2.6%) of 500 controls, (OR 7.38; CI 4.21-12.9). C4BQ0 was significantly more frequent in the 93 cirrhotic patients than in 93 cirrhotic controls without familiarity (Hardy-Weinberg equilibrium: chi2 5.76, P = 0.016) and in 20 families with versus 20 without aggregation of HCV related cirrhosis (29.2% versus 11.3%, P = 0.001); the association C4BQ0-HCV was found almost only in cirrhotic patients with a family history of liver cirrhosis. CONCLUSIONS: Our studies support the value of C4BQ0 as a risk indicator of familial HCV related cirrhosis

    Safety and effectiveness of gemcitabine for the treatment of classic Kaposi’s sarcoma without visceral involvement

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    Background: Classic Kaposi’s sarcoma (CKS) is a rare, multifocal, endothelial cell neoplasm that typically occurs in elderly people with previous infection by human herpes virus-8. Prospective trials are rare, and the choice of drugs relies on prospective trials performed on HIV-associated Kaposi’s sarcoma (KS). Pegylated liposomal anthracyclines and taxanes are considered the standard first- and second-line chemotherapy, respectively. Despite the indolent biologic behavior, the natural history is characterized by recurrent disease. This condition of chronic administration of cytotoxic drugs is often associated with immediate/long-term adverse events. Methods: This was an observational, retrospective study to evaluate the effectiveness and safety of gemcitabine in patients with CKS. From January 2016 to September 2021, the patients were treated with gemcitabine 1000 mg/m2 on days 1 and 8, with cycles repeated every 21 days. The treatment was administered as first or second line. Results: Twenty-seven (27) patients were included in the study. Twenty-one (21) out 27 patients (77.8%) achieved a partial response (PR), including 8 patients with major response (MR) (29.6%) and 13 patients with minor response (mR) (48.2%); 2 (7.4%) showed a complete response (CR), 3 (11.1%) a stable disease (SD), and 1 (3.7%) a progressive disease (PD). Tumor responses were generally rapid, with a median time to first response of 4 weeks (range, 3–12 weeks). Patients who responded had disease improvement with flattening of the skin lesions, decrease in the number of lesions, and substantial reduction in tumor-associated complications. Median duration of response was 19.2 months. Common adverse events were grades 1/2 thrombocytopenia, and grade 1 noninfectious fever. No patient discontinued treatment as a result of adverse events. Conclusion: Our study showed that gemcitabine is effective and well tolerated, acts rapidly on cutaneous lesions, and allows substantial symptom palliation, without dose-limiting toxicity. Gemcitabine represents a safe and effective option for the treatment of CKS

    Major eruptive style changes induced by structural modifications of a shallow conduit system: the 2007–2012 Stromboli case

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    Stromboli is known for its mild, persistent explosive activity from the vents located within the summit crater depression at the uppermost part of the Sciara del Fuoco (SdF) depression. Effusive activity (lava flows) at this volcano normally occurs every 5–15 years, involving often the opening of eruptive fissures along the SdF, and more rarely overflows from the summit crater. Between the end of the 2007 effusive eruption and December 2012, the number of lava flows inside and outside the crater depression has increased significantly, reaching a total of 28, with an average of 4.8 episodes per year. An open question is why this activity has become so frequent during the last 6 years and was quite rare before. In this paper, we describe this exceptional activity and propose an interpretation based on the structural state of the volcano, changed after the 2002–2003 and even more after the 2007 flank effusive eruption. We use images from the Stromboli fixed cameras network, as well as ground photos, plume SO2 and CO2 fluxes released by the summit crater, and continuous fumarole temperature recording, to unravel the interplay between magma supply, structural and morphology changes, and lava flow output. Our results might help forecast the future behaviour and hazard at Stromboli and might be applicable to other openconduit volcanoes.partially supported by the Project INGV-DPC Paroxysm V2/03, 2007–2009 funded by the Istituto Nazionale di Geofisica e Vulcanologia and the Italian Civil ProtectionPublished8413V. Dinamiche e scenari eruttiviJCR Journalrestricte

    Prevalence and Spectrum of Germline BRCA1 and BRCA2 Variants of Uncertain Significance in Breast/Ovarian Cancer: Mysterious Signals From the Genome

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    About 10–20% of breast/ovarian (BC/OC) cancer patients undergoing germline BRCA1/2 genetic testing have been shown to harbor Variants of Uncertain Significance (VUSs). Since little is known about the prevalence of germline BRCA1/2 VUS in Southern Italy, our study aimed at describing the spectrum of these variants detected in BC/OC patients in order to improve the identification of potentially high-risk BRCA variants helpful in patient clinical management. Eight hundred and seventy-four BC or OC patients, enrolled from October 2016 to December 2020 at the “Sicilian Regional Center for the Prevention, Diagnosis and Treatment of Rare and Heredo-Familial Tumors” of University Hospital Policlinico “P. Giaccone” of Palermo, were genetically tested for germline BRCA1/2 variants through Next-Generation Sequencing analysis. The mutational screening showed that 639 (73.1%) out of 874 patients were BRCA-w.t., whereas 67 (7.7%) were carriers of germline BRCA1/2 VUSs, and 168 (19.2%) harbored germline BRCA1/2 pathogenic/likely pathogenic variants. Our analysis revealed the presence of 59 different VUSs detected in 67 patients, 46 of which were affected by BC and 21 by OC. Twenty-one (35.6%) out of 59 variants were located on BRCA1 gene, whereas 38 (64.4%) on BRCA2. We detected six alterations in BRCA1 and two in BRCA2 with unclear interpretation of clinical significance. Familial anamnesis of a patient harboring the BRCA1-c.3367G>T suggests for this variant a potential of pathogenicity, therefore it should be carefully investigated. Understanding clinical significance of germline BRCA1/2 VUS could improve, in future, the identification of potentially high-risk variants useful for clinical management of BC or OC patients and family members

    Crustal dynamics of Mt. Vesuvius from 1998 to 2005: effects on seismicity and fluid circulation

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    This study presents the results of hydrogeochemical and seismological studies carried out at Mt. Vesuvius during the period June 1998 – December 2005. The data-set used for the seismological analysis was collected by: 1. The permanent seismic network of the INGV -Osservatorio Vesuviano, at the present composed of 11 short-period 1-Hz Mark L4C and Geotech S13 geophones and 2 broad band (40s) Guralp CMG40T seismometers; 2. Five digital stations (Lennartz PCM 5800) equipped with 3-component 1-Hz Lennartz LE-3Dlite sensors also operate in the area, in local recording mode. The monitered geochemical parameters (water temperature, pH, Eh, major ions, dissolved gases, 18O/16O ratios of groundwater) were detected at 10 private wells and 1 spring. Continuous soil temperature of the fumarolic fields was measured by a permanent device Gemini Tinytag Plus logger. Hydrogeochemical data show the occurrence of smooth long-term variations in the total dissolved salts (TDS) and bicarbonate contents of the groundwaters, accompanied by a general decline of water temperatures. These variations do not depend on changes in hydrologic regime, as suggested by the analysis of temporal distributions of air temperature and rainfall amount in the Vesuvius area. The changes in the geochemical pararameters are accompanied by a slight variations in both the seismicity rate and energy release. A further relationship between seismic activity and fluid discharge rate is highlighted by a particular episode occurred in August 2005, when a soil thermal anomaly was observed few weeks before the occurrence of a very shallow earthquake. Moment tensor analysis of this earthquake suggests that the most plausible source mechanism is a shear faulting combined with a tensile crack opening. This feature is often observed in volcanic areas and it is usually related to fluid-/gas-driven rock fracturing. The observed seismological, hydrological and geochemical temporal changes are interpreted not as changes of the volcanic system, but in terms of an external forcing, identified in the variation of the regional and local stress field acting on the volcano
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