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Presently, steam reforming of bio-ethanol is considered as a promising route for generation of H2-rich mixtures with very low environmental concerns. However, the main challenges of such technology are related to catalyst deactivation due to carbon formation. In fact, bioethanol mixtures, besides water and ethanol, may contain several impurities, including higher alcohols, which decrease catalyst resistance towards coking. In the present work, ethanol steam reforming was investigated over bimetallic Pt-Ni based catalysts supported on ceria-zirconia. Preliminary tests were carried out under pure water/ethanol mixture and the impact of temperature (400 - 500 °C), space velocity (7,500 - 30,000 h-1) and H2O/C2H5OH molar ratio (3 - 9) on carbon formation rate was studied. Further, at chosen operative conditions, a model mixture containing 1 mol% of the main bioethanol impurities (C2H4O, C3H7OH, C4H9OH, C5H11OH) was fed to the reformer and its effect on catalyst stability was studied at 450 °C, 15,000 h-1 and r.a.=6.

Ethanol is increasingly growing as feedstock for syngas production. In this work, a detailed kinetic mechanism for the oxidative steam reforming (OSR) of ethanol over a Pt-Ni/CeO2-SiO2 catalyst has been compared against experimental data and apparent kinetics. The rate of production and sensitivity analyses were performed to identify reaction paths, species, and reactions having a significant impact on the distribution of the products. The results have demonstrated that the formation of CH3CHO, which leads to the CH3 and CO, is due to the hydrogen abstraction forming the CH3CHOH, whereas the formation of C2H4, which leads to HCO, CH3, and coke precursors, is related to the pathways forming CH2CH2OH. The production of CH2CH2OH is successfully hindered by the presence of catalysts, giving a phenomenological reason for the suppression in coke formation. This analysis provides theoretical insights into the kinetic aspects of OSR, aiming at the development of optimized catalysts.

Being part of one of the fastest growing area in Artificial Intelligence (AI), virtual assistants are nowadays part of everyone's life being integrated in almost every smart device. Alexa, Siri, Google Assistant, and Cortana are just few examples of the most famous ones. Beyond these off-the-shelf solutions, different technologies which allow to create custom assistants are available. IBM Watson, for instance, is one of the most widely-adopted question-answering framework both because of its simplicity and accessibility through public APIs. In this work, we present a virtual assistant that exploits the Watson technology to support students and staff of a smart campus at the University of Palermo. Some in progress results show the effectiveness of the approach we propose.

Online Social Networks (OSNs) have become increasingly popular both because of their ease of use and their availability through almost any smart device. Unfortunately, these characteristics make OSNs also target of users interested in performing malicious activities, such as spreading malware and performing phishing attacks. In this paper we address the problem of spam detection on Twitter providing a novel method to support the creation of large-scale annotated datasets. More specifically, URL inspection and tweet clustering are performed in order to detect some common behaviors of spammers and legitimate users. Finally, the manual annotation effort is further reduced by grouping similar users according to some characteristics. Experimental results show the effectiveness of the proposed approach.

Background: In patients on dialysis coronary artery calcification (CAC) rapidly proceeds due to impaired mineral metabolism and/or exogenous calcium load. Progression has not been assessed in patients with chronic kidney disease not yet requiring dialysis (CKD patients). In this study, rate and determinants of CAC progression have been evaluated in CKD patients who are exposed to minor derangement of mineral metabolism and calcium load. Methods: Consecutive patients were enrolled. Exclusion criteria were: symptomatic coronary disease, arrhythmia, myocardial infarction, and diabetes. Serum calcium, phosphorus, parathyroid hormone, homocysteine, C-reactive protein, triglycerides, total cholesterol, high- and low-density lipoprotein cholesterol were serially measured. Fetuin-A was assessed at entry into the study. CAC progression was detected by measuring total calcium score (TCS) with computed tomography. Initial and final scans were obtained. Predictive factors of progression were investigated. Results: Fifty-three patients had CKD (stage 3–5 CKD; K-DOQI classification) not yet requiring dialysis, and 60 patients had normal renal function (NRF patients). Follow-up lasted 24 ± 4.2 months (mean ± SE). Patients with CAC were older with lower serum fetuin-A. TCS increased from 73 ± 17 to 80 ± 20 (mean ± SE; p = NS) in NRF patients, and from 384 ± 116 to 602 ± 140 (mean ± SE; p < 0.01) in CKD patients. Serum phosphorus [OR = 1.97 (1.14–3.41, 95% CI); p = 0.015] was the only variable that was associated with CAC progression. Cardiovascular events occurred in CKD patients with CAC. Conclusion: CAC progression was prominent in CKD patients and correlated with serum phosphorus. Fatal and nonfatal cardiovascular events were more frequent in CKD patients. Studies are required to ascertain whether the attainment of serum phosphorus concentration lower than that suggested by current guidelines may reduce CAC progression and ultimately mortality.

L'articolo indaga sulle trasformazioni di Bratislava, divenuta capitale della Slovacchia nel 1993, a seguito della separazione fra la Repubblica ceca e quella slovacca. La città costituisce, pertanto, un esempio interessante di città europea per le molteplici sfide affrontate negli ultimi decenni e legate alla transizione post-socialista, ma anche alla costruzione di nuovi simboli e relazioni a livello nazionale e internazionale. Le caratteristiche che contribuiscono alla valorizzazione contemporanea di Bratislava derivano però anche dalla storia e dalla geografia. Infatti la città occupa una posizione strategica lungo il Danubio a pochi chilometri da Vienna,in un territorio che si può considerare emblematico dell'Europa centrale, in quanto contraddistinto fino alla seconda guerra mondiale da un insediamento multietnico e multiculturale. Una maggiore attenzione alla diversità locale è riemersa dopo il 1993, pur all’interno di una nuova realtà statuale improntata al nazionalismo

Coronary artery calcification is more prevalent in dialysis patients than in patients without kidney disease and this is associated with high serum phosphorus. In this study, we evaluate the effect of calcium carbonate or sevelamer treatments on the progression of calcification in 90 predialysis patients. Inclusion criteria were stable serum calcium, phosphorus, parathyroid hormone, and a similar baseline total calcium score (TCS). These patients were not treated by phosphate binder, vitamin D, or statin. They were given low-phosphorus diets without or with daily calcium carbonate or sevelamer throughout the study that averaged 2 years. Baseline demographic or clinical characteristics along with biochemical parameters were not different among the three groups. The TCS significantly increased in patients on the low-phosphorus diet alone, to a lesser extent in calcium carbonate-treated patients, and not at all in sevelamer-treated patients. The progression of coronary calcification paralleled that of the calcium score. Our study shows that sevelamer treatment should not be restricted to dialysis patients; however, a larger study should be undertaken to confirm these results.