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Abstract: Chemical and isotopic analyses of the main gas manifestations of the island of Pantelleria (Italy) were used to gain insight on the origin of the released methane. Results indicate that the most probable origin is through abiogenic reactions within the hydrothermal system. Methane and CO2 flux measurements from the soils were made with the accumulation chamber method in an area of about 0.015km2 within the main fumarolic area of the island (Favara Grande). The 23 measurements range from −34 to 3550mgm−2 d−1 for CH4 and from 0.6 to 379gm−2 d−1 for CO2. The relationships between CH4 and CO2 fluxes and the CH4/CO2 ratios in the gases collected between the depths of 25 and 100cm provide evidence for methanotrophic processes within the soils. Methane output for the surveyed area was calculated to be 2.5ta−1 and extrapolated to about 5–10ta−1 for the entire volcanic/hydrothermal system of the island. Previous higher estimates of the CH4 output at Pantelleria (Etiope et al., 2007, J. Volcanol. Geotherm. Res., 165, 76–86) were based on soil CO2 output and CH4/CO2 ratios in fumarolic gases; the present work provides the first direct CH4 flux data and it suggests that methanotrophic activity in the soil could be substantial in reducing the CH4 emission to the atmosphere. [Copyright &y& Elsevier]

Abstract: Passive samplers were used to measure the atmospheric concentrations of SO2 naturally emitted at three volcanoes in Italy (Etna, Vulcano and Stromboli) and of H2S naturally emitted at three volcanic/geothermal areas in Greece (Milos, Santorini and Nisyros). The measured concentrations and dispersion patterns varied with the strength of the source (open conduits or fumaroles), the meteorological conditions and the area topography. At Etna, Vulcano and Stromboli, SO2 concentrations reach values that are dangerous to people affected by bronchial asthma or lung diseases (>1000μgm−3). H2S values measured at Nisyros also exceed the limit considered safe for the same group of people (>3000μgm−3). The data obtained using passive samplers represent time-averaged values over periods from a few days up to 1month, and hence concentrations probably reached much higher peak values that were potentially also dangerous to healthy people. The present study provides evidence of a peculiar volcanic risk associated with tourist exploitation of active volcanic areas. This risk is particularly high at Mt. Etna, where the elderly and people in less-than-perfect health can easily reach areas with dangerous SO2 concentrations via a cableway and off-road vehicles. [Copyright &y& Elsevier]

Abstract: Ischia volcano, in Central Italy, has long been known for its copious surface hydrothermal manifestations, signs of a pervasive circulation of hot fluids in the subsurface. Because of the significant chemical heterogeneity of fumarolic gas discharges and hot spring discharges, evidences of a complex hydrothermal setting, a definite model of fluid circulation at depth is currently unavailable, in spite of the several previous efforts. Here, we report on the chemical and isotopic composition of 120 groundwater samples, collected during several sampling surveys from 2002 to 2007. The acquired data suggest that the composition of surface manifestations reflect contributions from meteoric water, sea water, and thermal fluids rising from two distinct hydrothermal reservoir, with equilibrium temperatures of respectively ~150 °C and ~270 °C, and depths of 150–300 m and >300 m (but possibly >1000 m). We also make use of an isotopic characterization of the dissolved gas phase in thermal waters to demonstrate that the Ischia hydrothermal system is currently supplied by a deep-rising gas component (DGC), characterized by CO2 ~97.7±1.2 vol.% (on a water-free basis), δ 13CCO2 =−3.51±0.9‰, and helium isotopic ratio of about 3.5 Ra (3He/4He ratio normalized to the air ratio, R a), likely magmatic in origin. An assessment of the thermal budget for Ischia hydrothermal system is also presented, in the attempt to derive a first estimate of the size and rate of degassing of the magmatic reservoir feeding the gas emissions. We calculate that a heat flow of about 153–222 MW presently drives hydrothermal circulation on the island, which we suggest is supplied in convective form (e.g., by the ascent of a high-T magmatic vapour phase) by complete degassing of 2.2–3.3·107 m3 yr−1 of trachytic magma (with ~2.1 wt.% dissolved H2O content). If extrapolated to entire period of quiescence lasting since the Arso eruption in 1302 A.D., this volume corresponds to 1.6–2.3·1010 m3 of magma degassed in about 700 years of quiescent activity. [Copyright &y& Elsevier]

Abstract: This study reports on the first quantitative assessment of the geochemical cycling of volcanogenic elements, from their atmospheric release to their deposition back to the ground. Etna’s emissions and atmospheric depositions were characterised for more than 2years, providing data on major and trace element abundance in both volcanic aerosols and bulk depositions. Volcanic aerosols were collected from 2004 to 2007, at the summit vents by conventional filtration techniques. Precipitation was collected, from 2006 to 2007, in five rain gauges, at various altitudes around the summit craters. Analytical results for volcanic aerosols showed that the dominant anions were S, Cl, and F, and that the most abundant metals were K, Ca, Mg, Al, Fe, and Ti (1.5–50μgm−3). Minor and trace element concentrations ranged from about 0.001 to 1μgm−3. From such analysis, we derived an aerosol mass flux ranging from 3000 to 8000ta−1. Most analysed elements had higher concentrations close to the emission vent, confirming the prevailing volcanic contribution to bulk deposition. Calculated deposition rates were integrated over the whole Etna area, to provide a first estimate of the total deposition fluxes for several major and trace elements. These calculated deposition fluxes ranged from 20 to 80ta−1 (Al, Fe, Si) to 0.01–0.1ta−1 (Bi, Cs, Sc, Th, Tl, and U). Comparison between volcanic emissions and atmospheric deposition showed that the amount of trace elements scavenged from the plume in the surrounding of the volcano ranged from 0.1% to 1% for volatile elements such as As, Bi, Cd, Cs, Cu, Tl, and from 1% to 5% for refractory elements such as Al, Ba, Co, Fe, Ti, Th, U, and V. Consequently, more than 90% of volcanogenic trace elements were dispersed further away, and may cause a regional scale impact. Such a large difference between deposition and emission fluxes at Mt. Etna pointed to relatively high stability and long residence time of aerosols in the plume. [Copyright &y& Elsevier]

In this paper, in an attempt to reveal possible changes connected to natural or anthropogenic causes, the main results of hydrogeochemical monitoring carried out at Mount Etna are evaluated. We report on the salinity contents of the groundwaters that flow in fractured volcanics, which make up the flanks of the volcano. These waters, analyzed for major ion chemistry, were sampled regularly from 1994 to 2004. Basing on nonparametric Sen's slope estimator, time series of groundwater composition reveal that the salinity of most of the Etnean aquifers increased by 0.5% to 3.5% each year during this period. This change in the water chemistry is clearly referable to the overexploitation of the aquifers. This increasing trend needs to be inverted urgently; otherwise, it will cause a shortage of water in the near future, because the maximum admissible concentration of salinity for drinking water will be exceeded.

Many studies have assessed the strong influence of volcanic activity on the surrounding environment. This is particularly true for strong gas emitters such as Mt. Etna and Stromboli volcanoes. Among volcanic gases, fluorine compounds are potentially very harmful. Fluorine cycling through rainwater in the above volcanic areas was studied analysing more than 400 monthly bulk samples. Data indicate that only approximately 1% of fluorine emission through the plume is deposited on the two volcanic areas by meteoric precipitations. Although measured bulk rainwater fluorine fluxes are comparable to and sometimes higher than in heavily polluted areas, their influence on the surrounding vegetation is limited. Only annual crops, in fact, show some damage that could be an effect of fluorine deposition, indicating that long-living endemic plant species or varieties have developed some kind of resistance., (Copyright 2002 Elsevier Science B.V.)

The "Policlinico A. Gemelli" in the context of ongoing change in the Italian Health Care Service, has developed a Strategic Plan for 1996-2000. In this context a major role is played by the reengineering project, divided into there sequential phases of implementation. The natural evolution of this project results in a department-oriented organization in order to complete and implement change.

Phase 2 of reengineering project, the testing of solutions, was based on the definition of a Prototype, and the implementation of the Pilot phase. This gradual process has facilitated the organizational change and laid the foundations of subsequent extension phase. Ongoing initiatives concern the introduction of two new centers (wards and outpatient service) and the reorganization of ward and operating room activities.

Radiology has a significant impact on all health care processes at the "Policlinico A. Gemelli". The performance of Radiology rooms was thus analyzed within the overall performance of health care processes (e.g. medical wards, emergency service, day hospital). In this context, in the assessment phase of the reengineering project the Radiology room productivity has been analyzed. From outcomes of this analysis it appears that there is a high potential for increasing the Radiology room productivity (except for TC and MRI rooms). It has been observed that a better ward/service communication, together with a better use and planning of Radiology rooms and resources would allow a more efficient performance of the service. The reengineering project has led to a reorganization of the communication between Radiology rooms and wards/day hospital, a better inpatient transfer system from wards to Radiology rooms and the planning of the requests for exams. At present, a team is working in order to introduce a medium term budget of exams for all the wards associated to the provision of care for those diseases for which patient admission can be planned based on available Radiology rooms.

The identification of promoting factors of excellence improvement in radiology service management means to clearly assess how the different aspects of the service are managed. The key elements for intervention are sharply differentiated according to the service managerial level. The approach to continuous improvement should be a useful tool of assessment even when all its potentialities have been exhausted and new promoting factors are necessary to move to the subsequent stage.

Planning and scheduling of radiologic exams represent one of the crucial aspects in the performance of Diagnostic Imaging service, whose optimal management should lead to optimal efficiency and exploitation of technological and professional resources. A Diagnostic Imaging service with agreed and scheduled exams for customers achieves a more adequate, precise planning of the activity with optimum productivity of radiology rooms and anticipated workload assessment.