147 research outputs found

    Numerical modeling and characterization of a peculiar flow-like landslide

    Get PDF

    Industrial Ceramics: From Waste to New Resources for Eco-Sustainable Building Materials

    Get PDF
    Today, the need to dispose of a huge amount of ceramic industrial waste represents an important problem for production plants. Contextually, it is increasingly difficult to retrieve new mineral resources for the realization of building materials. Reusing ceramic industrial waste as precursors for building blocks/binders, exploiting their aluminosilicate composition for an alkaline activation process, could solve the problem. This chemical process facilitates the consolidation of new binders/blocks without thermal treatments and with less CO2 emissions if compared with traditional cements/ceramics. The alkali-activated materials (AAMs) are today thought as the materials of the future, eco-sustainable and technically advanced. In this study, six different kind of industrial ceramic waste are compared in their chemical and mineralogical composition, together with their thermal behaviour, reactivity in an alkaline environment and surface area characteristics, with the aim of converting them from waste into new resources. Preliminary tests of AAM synthesis by using 80%–100% of ceramic waste as a precursor show promising results. Workability, porosity and mechanical strengths in particular are measured, showing as, notwithstanding the presence of carbonate components, consolidated materials are obtained, with similar results. The main factors which affect the characteristics of the synthetized AAMs are the precursors’ granulometry, curing temperature and the proportions of the activating solutions

    A Multidisciplinary Methodology for Technological Knowledge, Characterization and Diagnostics: Sandstone Facades in Florentine Architectural Heritage

    Get PDF
    The Historic Center of Florence, a UNESCO World Heritage Site, includes many examples of architecture characterized by rough-hewn rusticated block facades—a very common masonry technique in the Florentine Renaissance—made in Pietraforte sandstone. The latter features numerous criticalities related to its intrinsic characteristics and to decay phenomena that are due to weathering and pollution. A multidisciplinary methodology has been developed starting from historic analysis and architectural survey to a complete optometric, mechanical, physical, mineralogical, and petrographic characterization of rough-hewn rusticated blocks, applied to the case study of the Palazzo Medici Riccardi facades. The studies performed in this work cover several research fields, from architecture to geology, going through material diagnostics, and aim at improving knowledge and designing new restoration solutions for Pietraforte building-material criticalities. The research proposes an operative protocol aimed at supporting restoration projects and monitoring plans, with the aim to protect historical, architectural, and artistic cultural heritage and to safeguard the people who visit the city of Florence every year

    A Multidisciplinary Methodology for Technological Knowledge, Characterization and Diagnostics: Sandstone Facades in Florentine Architectural Heritage

    Get PDF
    The Historic Center of Florence, a UNESCO World Heritage Site, includes many examples of architecture characterized by rough-hewn rusticated block facades—a very common masonry technique in the Florentine Renaissance—made in Pietraforte sandstone. The latter features numerous criticalities related to its intrinsic characteristics and to decay phenomena that are due to weathering and pollution. A multidisciplinary methodology has been developed starting from historic analysis and architectural survey to a complete optometric, mechanical, physical, mineralogical, and petrographic characterization of rough-hewn rusticated blocks, applied to the case study of the Palazzo Medici Riccardi facades. The studies performed in this work cover several research fields, from architecture to geology, going through material diagnostics, and aim at improving knowledge and designing new restoration solutions for Pietraforte building-material criticalities. The research proposes an operative protocol aimed at supporting restoration projects and monitoring plans, with the aim to protect historical, architectural, and artistic cultural heritage and to safeguard the people who visit the city of Florence every year

    From hot rocks to glowing avalanches: Numerical modelling of gravity-induced pyroclastic density currents and hazard maps at the Stromboli volcano (Italy)

    Get PDF
    Gravity-induced pyroclastic density currents (PDCs) can be produced by the collapse of volcanic crater rims or due to the gravitational instability of materials deposited in proximal areas during explosive activity. These types of PDCs, which are also known as “glowing avalanches”, have been directly observed, and their deposits have been widely identified on the flanks of several volcanoes that are fed by mafic to intermediatemagmas. In this research, the suitability of landslide numerical models for simulating gravity-induced PDCs to provide hazard assessmentswas tested. This work also presents the results of a back-analysis of three events that occurred in 1906, 1930 and 1944 at the Stromboli volcano by applying a depth-averaged 3Dnumerical code named DAN-3D. The model assumes a frictional internal rheology and a variable basal rheology (i.e., frictional, Voellmy and plastic). The numerical modelling was able to reproduce the gravity-induced PDCs' extension and deposit thicknesses to an order ofmagnitude of that reported in the literature. The best resultswhen comparedwith field datawere obtained using a Voellmymodelwith a frictional coefficient of f=0.19 and a turbulence parameter Ο=1000 m s−1. The results highlight the suitability of this numerical code,which is generally used for landslides, to reproduce the destructive potential of these events in volcanic environments and to obtain information on hazards connected with explosive-related, mass-wasting phenomena in Stromboli Island and at volcanic systems characterized by similar phenomena.Published93-1065V. Dinamica dei processi eruttivi e post-eruttiviJCR Journa

    Fabry disease presenting with sudden hearing loss and otosclerosis : a case report

    Get PDF
    Introduction: Fabry disease is an X-linked lysosomal storage disorder resulting in a multiple-system disorder with a wide spectrum of physical signs and symptoms, predominantly affecting the central and peripheral nervous systems, skin, heart, kidneys, and eyes. Case presentation: We describe the case of a 26-year-old European Caucasian man who had Fabry disease and who presented with episodic sudden unilateral hearing loss and was treated with glucocorticoids, pentoxifylline, hyperbaric oxygen, and fluoride because of concomitant audiometric evidence of otosclerosis. This case demonstrates the partial and transient beneficial effect of standard treatment for sudden hearing loss not related to Fabry disease and analyzes the possible connection between typical Fabry disease inner-ear lesions and otosclerosis. Whereas hearing loss has been described in connection with Fabry disease, otosclerosis-associated hearing loss in Fabry disease has not yet been described. Conclusions: Although progressive hearing loss in patients with Fabry disease seems to be influenced by replacement therapy, few data concerning treatment of sudden hearing loss are available. The lack of literature concerning the pathogenesis of the otological involvement in Fabry disease makes it impossible to identify a connection between the latter and otosclerosis. Therefore, this report may help to reinforce the importance of a thorough evaluation of hearing in patients with Fabry disease and may be of help with therapeutic decisionmaking

    Increased Perioperative N-Terminal Pro-B-Type Natriuretic Peptide Levels Predict Atrial Fibrillation After Thoracic Surgery for Lung Cancer

    Get PDF
    Background— Postoperative atrial fibrillation (AF) is a complication of thoracic surgery for lung cancer, with a reported incidence that can run as high as 42%. Recently, it has been observed retrospectively that B-type natriuretic peptide predicts AF after cardiac surgery. We performed a prospective study to evaluate the role of N-terminal pro–B-type natriuretic peptide (NT-proBNP) as a marker for risk stratification of postoperative AF in patients undergoing thoracic surgery for lung cancer. Methods and Results— We measured NT-proBNP levels in 400 patients (mean age, 62±10 years; 271 men) 24 hours before and 1 hour after surgery. The primary end point of the study was the incidence of postoperative AF. Overall, postoperative AF occurred in 72 patients (18%). Eighty-eight patients (22%) showed an elevated perioperative NT-proBNP value. When patients with either preoperatively or postoperatively elevated NT-proBNP were pooled, a greater incidence of AF was observed compared with patients with normal values (64% versus 5%; P <0.001). At multivariable analysis, adjusted for age, gender, major comorbidities, echocardiography parameters, pneumonectomy, and medications, both preoperative and postoperative NT-proBNP values were independent predictors of AF (relative risk, 27.9; 95% CI, 13.2 to 58.9; P <0.001 for preoperative NT-proBNP elevation; relative risk, 20.1; 95% CI, 5.8 to 69.4; P <0.001 for postoperative NT-proBNP elevation). Conclusions— Elevation of perioperative NT-proBNP is a strong independent predictor of postoperative AF in patients undergoing thoracic surgery for lung cancer. This finding should facilitate studies of therapies to reduce AF in selected high-risk patients

    Circulating MicroRNAs as Potential Predictors of Anthracycline-Induced Troponin Elevation in Breast Cancer Patients: Diverging Effects of Doxorubicin and Epirubicin

    Get PDF
    Anthracyclines are anti-neoplastic drugs presenting cardiotoxicity as a side effect. Cardiac troponins (cTn) and echocardiography are currently used to assess cardiac damage and dysfunction, but early biomarkers identifying patients in need of preventive treatments remain a partially met need. Circulating microRNAs (miRNAs) represent good candidates, so we investigated their possible roles as predictors of troponin elevation upon anthracycline treatment. Eighty-eight female breast cancer patients administered with doxorubicin (DOX) or epirubicin (EPI) were divided into four groups basing on drug type and cTn positive (cTn+) or negative (cTn-) levels: DOX cTn-, DOX cTn+, EPI cTn- and EPI cTn+. Blood was collected at baseline, during treatment, and at follow-up. We identified plasma miRNAs of interest by OpenArray screening and single assay validation. Our results showed miR-122-5p, miR-499a-5p and miR-885-5p dysregulation in DOX patients at T0, identifying a signature separating, with good accuracy, DOX cTn- from DOX cTn+. No miRNAs showed differential expression in EPI subjects. Conversely, an anthracycline-mediated modulation (regardless of cTn) was observed for miR-34a-5p, -122-5p and -885-5p. Our study indicates specific circulating miRNAs as possible prediction markers for cardiac troponin perturbation upon anthracycline treatment. Indeed, our findings hint at the possible future use of plasma miRNAs to predict the cardiac responsiveness of patients to different anticancer agents

    Economy-wide analysis of food waste reductions and related costs

    Get PDF
    Reducing food waste has become a policy priority in recent years as many studies show that a significant amount of food is wasted at various stages of the food supply chain. However, the economic impacts of food waste reduction have not been studied in depth as most of the studies in the literature ignore the cost and feedback effects. The aim of this report is to develop a general framework to analyse the economic impacts of reducing food waste in EU28 in both a global and a regional context in support of the EU policy making process on food waste reduction. For the purposes of this study, we employ the CGEBox toolbox which is a flexible, extendable, and modular code basis for CGE modelling. The default configuration of CGEBox used in this study covers the global economy with a detailed representation of the agriculture and food production sector whereas the EU28 is modelled at NUTS-II level. The impact of a food waste reduction equal to 5% of the intermediate input use of food processing sectors under two different cost assumptions is analysed in the scenarios. Firstly, in the cost neutral scenario, we assume that the cost of reducing food waste is equal to the monetary savings for the food processing industry. Secondly, in the pessimistic scenario, we assume that the cost of reducing food waste is twice as much as the cost savings made by reducing food waste. The results suggest that a unilateral commitment by the EU to reducing food loss and waste would most likely decrease the competitiveness of the EU’s food processing. Reduced demand for primary agricultural inputs would shrink the EU’s agricultural sectors, putting pressure on farm incomes and land prices. The contribution to global food security would be very minor. The impact on emissions relevant to climate change at global level is also minor, with a very limited contribution within the EU
    • 

    corecore