Le fumarole vulcaniche

Il magma che alimenta i vulcani, oltre ad essere costituito da roccia fusa, è anche ricco di fluidi, tra i quali i più abbondanti sono l’acqua (H2O), l’anidride carbonica (CO2), i composti dello zolfo come l’anidride solforosa (SO2) e l’idrogeno solforato (H2S) ed infine, in concentrazioni minori, anche gli acidi fluoridrico (HF) e cloridrico (HCl)

Georeferenced cartography dataset of the La Fossa crater fumarolic field at Vulcano Island (Aeolian Archipelago, Italy): conversion and comparison of data from local to global positioning methods

The present study illustrates the procedures applied for the coordinate system conversion of the historical fumarole positions at La Fossa crater, to allow their comparison with newly acquired global positioning system (GPS) data. Due to the absence of ground control points in the field and on both the old Gauss Boaga and the new UTM WGS 1984 maps, we had to model the transformation errors between the two systems using differential GPS techniques. Once corrected, the maps show a residual Easting shifting, due to erroneous georeferencing of the original base maps; this is corrected by morphological comparative methods. The good correspondence between the corrected positions of the historical data and the results of the new GPS survey that was carried out in 2009 highlights the good quality of the old surveys, although they were carried out without the use of accurate topographical instruments

A landscape approach in the isotopic modeling of natural precipitations: two cases in Mediterranean mountain areas

The present paper proposes a method to simplify the very complex isotopic fractionation processes occurring during the water cycle. The method is constrained by a relatively small number of variables, with the precision needed in hydrological applications. After a theoretical introduction on the adopted interpolation criteria, two cases in the Mediterranean are presented. In both cases the evaluation of the “geometric complexity” of the systems appears to be the best tool to produce reliable isotopic models. If the complexity is low, it is apparently easier to fit different models; on the contrary the higher the complexity is, more difficult it is to find a reliable model but, at the same time, more difficult it is to find effective alternative models

Milk composition of "Nero Siciliano" sow. Preliminary results

AbstractQuantitative and qualitative milk production is the basis for determining the nutritional requirements of lactating sow; indeed, the gross nutrient composition of sow's milk is frequently used as a suitable starting point when formulating milk-replacer diets for piglets. Data about the sow's milk can be found from the literature but, in authors knowledge, no data on milk composition of Nero Siciliano sow exist. This study reports the preliminary results concerning some physical and chemical characteristics of the milk of this autochthonous Sicilian pig race during the lactation.The research was carried out on 10 "Nero Siciliano" sows, 4 primiparous (age: 9-12 months) and 6 pluriparous (age: 2-5 years), stabled in single boxes and fed with a concentrate. From the 10th day after farrowing to the weaning (day 58th), every week, in the morning, the sows were injected with 5 IU oxytocin (i.m.) and hand-milked; all functional mammary glands were milked. Piglets were removed and isolated from the dams fo..

Anthropogenic sinkholes in the Marsala area (western Sicily) linked to underground quarries

Marsala territory (western Sicily) is characterized by the presence of a Lower Pleistocene (Calabrian) calcarenite succession (Marsala Calcarenite Fm). It can be divided into three lithofacies that show the regressive evolution of the depositional system: a) coarse to fine yellow bio- and lithoclastic calcarenites, b) sands, and c) gray sandy clays. At least 80 m-thick, this succession gently dips (5-10) towards the south and the south-west. At some locations the Marsala Calcarenite is covered by Middle and Upper Pleistocene marine terraced deposits. Since the Roman period, due to the great abundance of calcarenite rocks, and to the facility of extraction, the Marsala area has been characterized by a high number of quarries for the extraction of this building materials. Many of them were excavated underground, at depth varying from a few meters to about 25 m, and are arranged in one or two levels, following the galleries and pillars excavation technique. With time, the underground quarries have been progressively abandoned for the decay of the physical and mechanical properties of the calcarenite rock mass, the interaction with the groundwater, the high costs of extraction, and the dangers and difficulties encountered in working underground. Since the 1960’s the quarries have been affected by instability processes, visible through collapses and deformations of vaults and pillars. These phenomena often propagate upward reaching the topographic surface and forming sinkholes which affect and severely damage the built-up area. In particular, two case studies of sinkholes related to different underground quarries will be analyzed in this paper. The aim is to provide a description of the most significant processes and factors responsible of the instability processes based on field surveys, as well as to understand the generation mechanisms of these anthropogenic sinkholes by means of numerical modeling, based on rock laboratory testing data, that represents in these cases a remarkable tool for the investigation of the cause-effect relationships, as already performed in other areas of Italy

Prognostic indicators of successful endoscopic sclerotherapy for prevention of rebleeding from oesophageal varices in cirrhosis: a long-term cohort study.

BACKGROUND: Although band ligation is now recommended for prevention of rebleeding from oesophageal varices in cirrhosis, sclerotherapy is still widely used. Patients submitted to chronic sclerotherapy undergo several endoscopies and experience a large number of serious complications. However, long-term outcome is poorly defined. AIMS: To assess the clinical course and prognostic indicators of patients undergoing chronic sclerotherapy for prevention of variceal rebleeding as a basis for future evaluation of long-term band ligation outcome. METHODS: Prospective cohort study; prognostic analysis by the Cox proportional hazards model. RESULTS: A total of 218 consecutive cirrhotic patients (37 Child class A, 154 B, 27 C) were enrolled in the study Varices were obliterated in 139 (64%) patients in a mean of 5 (+/-2.6) sessions and recurred in 58/139 (41.7%) within one year. A total of 132 (60%) patients experienced 283 rebleeding episodes and 73 (33%) died. Bleeding from oesophageal ulcers was the most serious complication causing 14% of all rebleeding episodes. Significant prognostic indicators of sclerotherapy outcome were: Child-Pugh class for variceal obliteration; gastric varices and platelet count for recurrence of varices; failure to obliterate varices, variceal size and gastric varices for rebleeding; blood urea nitrogen and failure to obliterate varices for death. Presence of gastric varices was the only prognostic indicator for death in the 79 patients not achieving variceal obliteration. A mean of 10 endoscopies and of 6 hospital admissions were needed per each patient with an estimated cost of US dollars 7154 per patient during the first two years of therapy. CONCLUSIONS: Sclerotherapy is a very demanding and costly treatment, and is associated with frequent and serious side-effects. The probability of treatment failure is significantly higher in Child C patients with gastric varices. Alternative treatments should be considered for these patients

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

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

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

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