Numerical modelling of gas-water-rock interactions in volcanic-hydrothermal environment: the Ischia Island (Southern Italy) case study.

Hydrothermal systems hosted within active volcanic systems represent an excellent opportunity to investigate the interactions between aquifer rocks, infiltrating waters and deep-rising magmatic fluids, and thus allow deriving information on the activity state of dormant volcanoes. From a thermodynamic perspective, gas-water-rock interaction processes are normally far from equilibrium, but can be represented by an array of chemical reactions, in which irreversible mass transfer occurs from host rock minerals to leaching solutions, and then to secondary hydrothermal minerals. While initially developed to investigate interactions in near-surface groundwater environments, the reaction path modeling approach of Helgeson and co-workers can also be applied to quantitative investigation of reactions in high T-P environments. Ischia volcano, being the site of diffuse hydrothermal circulation, is an ideal place where to test the application of reaction-path modeling. Since its last eruption in 1302 AD, Ischia has shown a variety of hydrothermal features, including fumarolic emissions, diffuse soil degassing and hot waters discharges. These are the superficial manifestation of an intense hydrothermal circulation at depth. A recent work has shown the existence of several superposed aquifers; the shallowest (near to boiling) feeds the numerous surface thermal discharges, and is recharged by both superficial waters and deeper and hotter (150-260° C) hydrothermal reservoir fluids. Here, we use reaction path modelling (performed by using the code EQ3/6) to quantitatively constrain the compositional evolution of Ischia thermal fluids during their hydrothermal flow. Simulations suggest that compositions of Ischia groundwaters are buffered by interactions between reservoir rocks and recharge waters (meteoric fluids variably mixed - from 2 to 80% - with seawater) at shallow aquifer conditions. A CO2 rich gaseous phase is also involved in the interaction processes (fCO2 = 0.4-0.6 bar). Overall, our model calculations satisfactorily reproduce the main chemical features of Ischia groundwaters. In the model runs, attainment of partial to complete equilibrium with albite and K-feldspar fixes the Na/K ratios of the model solutions at values closely matching those of natural samples. Precipitation of secondary phases, mainly clay minerals (smectite and saponite) and zeolites (clinoptilolite), during the reaction path is able to well explain the large Mg-depletions which characterise Ischia thermal groundwaters; while pyrite and troilite are shown to control sulphur abundance in aqueous solutions. SiO2(aq) contents in model simulations fit those measured in groundwaters and are being buffered by the formation of quartz polymorphs and Si-bearing minerals. Finally, our simulations are able to reproduce redox conditions and Fe-depletion trends of natural samples. We conclude that reaction path modelling is an useful tool for quantitative exploration of chemical process within volcano-hosted hydrothermal systems

Quantitative models of hydrothermal fluid–mineral reaction:The Ischia case

The intricate pathways of fluid–mineral reactions occurring underneath active hydrothermal systems are explored in this study by applying reaction path modelling to the Ischia case study. Ischia Island, in Southern Italy, hosts a well-developed and structurally complex hydrothermal system which, because of its heterogeneity in chemical and physical properties, is an ideal test sites for evaluating potentialities/limitations of quantitative geochemical models of hydrothermal reactions. We used the EQ3/6 software package, version 7.2b, to model reaction of infiltrating waters (mixtures of meteoric water and seawater in variable proportions) with Ischia’s reservoir rocks (the Mount Epomeo Green Tuff units; MEGT). The mineral assemblage and composition of such MEGT units were initially characterised by ad hoc designed optical microscopy and electron microprobe analysis, showing that phenocrysts (dominantly alkali–feldspars and plagioclase) are set in a pervasively altered (with abundant clay minerals and zeolites) groundmass. Reaction of infiltrating waters with MEGT minerals was simulated over a range of realistic (for Ischia) temperatures (95–260° C) and CO2 fugacities (10 ^-0.2 to 10^0.5) bar. During the model runs, a set of secondary minerals (selected based on independent information from alteration minerals’ studies) was allowed to precipitate from model solutions, when saturation was achieved. The compositional evolution of model solutions obtained in the 95–260°C runs were finally compared with compositions of Ischia’s thermal groundwaters, demonstrating an overall agreement. Our simulations, in particular, well reproduce the Mg-depleting maturation path of hydrothermal solutions, and have end-of-run model solutions whose Na–K–Mg compositions well reflect attainment of full-equilibrium conditions at run temperature. High-temperature (180–260° C) model runs are those best matching the Na–K–Mg compositions of Ischia’s most chemically mature water samples, supporting quenching of deep-reservoir conditions for these surface manifestations; whilst Fe, SiO2 and, to a lesser extent, SO4 contents of natural samples are better reproduced in low-temperature (95°C) runs, suggesting that these species reflect conditions of water–rock interaction in the shallow hydrothermal environment. The ability of model runs to reproduce the compositional features of Ischia’s thermal manifestations, demonstrated here, adds supplementary confidence on reaction path modelling as a realistic and insightful representation of mineral–fluid hydrothermal reactions. Our results, in particular, demonstrate the significant impact of host rock minerals’ assemblage in governing the paths and trends of hydrothermal fluids’ maturation

A tool for evaluating geothermal power exploitability and its application to Ischia, Southern Italy

The paper proposes a method to evaluate the potential for electric power production at any site of possible geothermal interest. Accounting for geological data of the reservoirs, the method allows the computation of the available electrical power of the investigated site. Electrical energy production from geothermal sources is realized through different techniques, such as single flash and double flash, dry steam, and binary ORC plants. The technique chosen to be the most productive is determined by analyzing a specific range of geofluid properties, mainly temperature and pressure. Moreover, each plant typology has a global efficiency that may be correlated to geofluid enthalpy by empiric relations available in literature. The proposed evaluation method brings together all these correlations, yielding the power availability from a geosource, once its temperature and pressure are known. The method takes as input the geofluid available flow rate, its pressure, temperature and non-condensable gas content. It defines the best plant option from these parameters, calculates its global efficiency and finally returns the actual available power. For sites of geothermic interest, such as the volcanic island of Ischia in Southern Italy, the results of the application of this new method clearly highlight the most suitable zones for power plants installations

Study of the effect of different breast implant surfaces on capsule formation and host inflammatory response in an animal model

Background: Breast implants are biomaterials eliciting a physiological and mandatory foreign body response. Objectives: The authors designed an animal study to investigate the impact of different implant surfaces on the formation of the periprosthetic capsule, the inflammatory response, and the cellular composition. Methods: The authors implanted 1 scaled-down version of breast implants by different manufactures on 70 female Sprague Dawley rats. Animals were divided into 5 groups of 14 animals. Group A received a smooth implant (Ra ≈ 0.5 µm) according to the ISO 14607-2018 classification, Group B a smooth implant (Ra ≈ 3.2 µm), Group C a smooth implant (Ra ≈ 5 µm), Group D a macrotextured implant (Ra ≈ 62 µm), and Group E a macrotextured implant (Ra ≈ 75 µm). At 60 days, all animals received a magnetic resonance imaging (MRI), and 35 animals were killed and their capsules sent for histology (capsule thickness, inflammatory infiltrate) and immunohistochemistry analysis (cellular characterization). The remaining animals repeated the MRI at 120 days and were killed following the same protocol. Results: MRI showed a thinner capsule in the smooth implants (Groups A-C) at 60 days (P < .001) but not at 120 days (P = .039), confirmed with histology both at 60 days (P = .005) and 120 days (P < .001). Smooth implants (Groups A-C) presented a mild inflammatory response at 60 days that was maintained at 120 days and a high M2-Macrophage concentration (anti-inflammatory). Conclusions: Our study confirms that smooth implants form a thinner capsule, inferior inflammatory infiltrate, and a cellular composition that indicates a mild host inflammatory response. A new host inflammatory response classification is elaborated classifying breast implants into mild, moderate, and high

First observations of the fumarolic gas output from a restless caldera: implications for the current period of unrest (2005–2013) at Campi Flegrei

The fumarolic gas output has not been quantified for any of the currently deforming calderas worldwide, due to the lack of suitable gas flux sensing techniques. In view of resumption of ground uplift (since 2005) and the associated variations in gas chemistry, Campi Flegrei, in southern Italy, is one of the restless calderas where gas flux observations are especially necessary. Here we report the first ever obtained estimate of the Campi Flegrei fumarolic gas output, based on a set of MultiGAS surveys (performed in 2012 and 2013) with an ad-hoc-designed measurement setup. We estimate that the current Campi Flegrei fumarolic sulphur (S) flux is low, on the order of 1.5–2.2 tons/day, suggesting substantial scrubbing of magmatic S by the hydrothermal system. However, the fumarolic carbon dioxide (CO2) output is 4606160 tons/day (mean6SD), which is surprisingly high for a dormant volcano in the hydrothermal stage of activity, and results in a combined (fumarolesþsoil) CO2 output of 1560 tons/ day. Assuming magma to be the predominant source, we propose that the current CO2 output can be supplied by either (i) a large (0.6–4.6 km3), deeply stored (>7 km) magmatic source with low CO2 contents (0.05–0.1 wt%) or (ii) by a small to medium-sized ( 0.01–0.1 km3) but CO2-rich (2 wt%) magma, possibly stored at pressures of 100 to 120 MPa. Independent geophysical evidence (e.g., inferred from geodetic and gravity data) is needed to distinguish between these two possibilities

Diabetes and erectile dysfunction. The relationships with health literacy, treatment adherence, unrealistic optimism, and glycaemic control

Purpose: The aim of this study was to evaluate the relationships between health literacy, unrealistic optimism, and adherence to glycometabolic disease management related to erectile dysfunction (ED) in male patients with type 2 diabetes (T2D) or preDM.Materials and Methods: This prospective observational study enroled 167 consecutive patients with T2D and ED. All patients underwent the following examinations: (a) medical history collection; (b) Body Mass Index (BMI) determination; (c) hormonal and biochemical assessment; (d) duration of T2D, complications and treatment; (e) International Index of Erectile Function-5 questionnaire to assess ED; and (f) validated questionnaire to evaluate health literacy, unrealistic optimism, and treatment adherence.Results: Overall, mean age was 62.5 +/- 9.4 years (range: 20-75) and mean BMI was 28.4 +/- 4.8 kg/m(2) (range: 18.4-46.6). The mean IIEF-5 score was 15.4 +/- 5.2 (range: 5-25). The majority of patients showed high health literacy. However, low health literacy was found in patients with higher IIEF-5 scores and high BMI. Unrealistic optimism was low in most patients. Higher adherence to treatment was found in patients who reported regular physical activity, who followed a diet, and in patients with a family history of T2D. Regarding anti-diabetic treatment, patients treated with insulin showed higher health literacy than patients not treated with other medications, whereas higher adherence was found in patients using SGLT2-i.Conclusions: This study highlighted the close relationship between metabolic compensation, BMI, ED, and psychological attitudes, including health literacy and unrealistic optimism

Steam and gas emission rates from La Soufrière of Guadeloupe (Antilles arc): implications for the magmatic supply degassing during unrest

Since its last magmatic eruption in 1530 AD, La Soufrière andesitic volcano in Guadeloupe has displayed intense hydrothermal activity and six phreatic eruptive crises (the last of which, in 1976-1977, with 73000 evacuees). Here we report on the first direct quantification of gas plume emissions from La Soufrière summit vents, which gradually intensified during the past 20 years. Gas fluxes were determined in 2006 then 2012 [1] by measuring the horizontal and vertical distribution of volcanic gas concentrations in the air-diluted plume, the composition of the hot fumarolic fluid at exit (108°C), and scaling to the speed of plume transport (in situ measurements and FLIR imaging). We first demonstrate that all fumarolic vents of La Soufrière are fed by a common H2O-rich (97-98 mol %) fluid end-member, emitted almost unmodified at the most active South Crater while affected by secondary alterations (steam condensation, sulphur scrubbing) at other vents. Daily fluxes in 2012 (200 tons of H2O, 15 tons of CO2, ~4 tons of H2S and 1 ton of HCl) were augmented by a factor ~3 compared to 2006, in agreement with increasing activity. Summit fumarolic degassing contributes most of the bulk volatile and heat budget (8 MW) of the volcano. Isotopic evidences demonstrate that La Soufrière hydrothermal emissions are sustained by continuous heat and gas supply from an andesitic magma reservoir confined at 6-7 km depth. This magmatic supply mixes with abundant groundwater of tropical meteoric origin in the hydrothermal system. Based on petro-geochemical data for the erupted magma(s), we assess that the volcanic gas fluxes in 2012 can be accounted for by the release of free magmatic gas derived from about 1000 m3 per day of the basaltic melt replenishing the reservoir at depth. In terms of mass budget, the current degassing unrest is compatible with enhanced free gas release from that reservoir, without requiring any (actually undetected) magma intrusion. We recommend a regular survey of the fumarolic gas flux from La Soufrière in order to anticipate the evolution of the magma reservoir. [1] P. Allard et al., Chemical Geology 384, 76-93, 2014

Diabetes and erectile dysfunction: The relationships with health literacy, treatment adherence, unrealistic optimism, and glycaemic control

Purpose: The aim of this study was to evaluate the relationships between health literacy, unrealistic optimism, and adherence to glycometabolic disease management related to erectile dysfunction (ED) in male patients with type 2 diabetes (T2D) or preDM. Materials and methods: This prospective observational study enroled 167 consecutive patients with T2D and ED. All patients underwent the following examinations: (a) medical history collection; (b) Body Mass Index (BMI) determination; (c) hormonal and biochemical assessment; (d) duration of T2D, complications and treatment; (e) International Index of Erectile Function-5 questionnaire to assess ED; and (f) validated questionnaire to evaluate health literacy, unrealistic optimism, and treatment adherence. Results: Overall, mean age was 62.5 ± 9.4 years (range: 20-75) and mean BMI was 28.4 ± 4.8 kg/m2 (range: 18.4-46.6). The mean IIEF-5 score was 15.4 ± 5.2 (range: 5-25). The majority of patients showed high health literacy. However, low health literacy was found in patients with higher IIEF-5 scores and high BMI. Unrealistic optimism was low in most patients. Higher adherence to treatment was found in patients who reported regular physical activity, who followed a diet, and in patients with a family history of T2D. Regarding anti-diabetic treatment, patients treated with insulin showed higher health literacy than patients not treated with other medications, whereas higher adherence was found in patients using SGLT2-i. Conclusions: This study highlighted the close relationship between metabolic compensation, BMI, ED, and psychological attitudes, including health literacy and unrealistic optimism

DEEP RESERVOIR TEMPERATURES OF LOW-ENTHALPY GEOTHERMAL SYSTEMS IN TUNISIA: NEW CONSTRAINTS FROM CHEMISTRY OF THERMAL WATERS

Tunisia is characterized by hot and warm groundwaters (temperature up to 75 °C) which represent the surface manifestation of geothermal systems hosted in carbonate-evaporite rock sequences. The T-conditions of Tunisia deep thermal reservoirs are here evaluated for the first time at the regional scale. The results here shown clearly highlight the limitations inherent in the application of common geothermometric methods in the estimation of equilibrium temperatures in sedimentary environments. The modeling approach proposed by Chiodini et alii (1995), which makes use of the ratios between dissolved HCO3, SO4 and F, provides the most reliable results, and allows us to derive equilibrium temperatures up to 200 °C for the Tunisian thermal reservoirs. Very high equilibrium pCO2 (100 bar) values are also estimated, likely indicative of the confined aquifer conditions

Further Clarification of Pain Management Complexity in Radiotherapy: Insights from Modern Statistical Approaches

Background: The primary objective of this study was to assess the adequacy of analgesic care in radiotherapy (RT) patients, with a secondary objective to identify predictive variables associated with pain management adequacy using a modern statistical approach, integrating the Least Absolute Shrinkage and Selection Operator (LASSO) algorithm and the Classification and Regression Tree (CART) analysis. Methods: This observational, multicenter cohort study involved 1387 patients reporting pain or taking analgesic drugs from 13 RT departments in Italy. The Pain Management Index (PMI) served as the measure for pain control adequacy, with a PMI score < 0 indicating suboptimal management. Patient demographics, clinical status, and treatment-related factors were examined to discern the predictors of pain management adequacy. Results: Among the analyzed cohort, 46.1% reported inadequately managed pain. Non-cancer pain origin, breast cancer diagnosis, higher ECOG Performance Status scores, younger patient age, early assessment phase, and curative treatment intent emerged as significant determinants of negative PMI from the LASSO analysis. Notably, pain management was observed to improve as RT progressed, with a greater discrepancy between cancer (33.2% with PMI < 0) and non-cancer pain (73.1% with PMI < 0). Breast cancer patients under 70 years of age with non-cancer pain had the highest rate of negative PMI at 86.5%, highlighting a potential deficiency in managing benign pain in younger patients. Conclusions: The study underscores the dynamic nature of pain management during RT, suggesting improvements over the treatment course yet revealing specific challenges in non-cancer pain management, particularly among younger breast cancer patients. The use of advanced statistical techniques for analysis stresses the importance of a multifaceted approach to pain management, one that incorporates both cancer and non-cancer pain considerations to ensure a holistic and improved quality of oncological care