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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.

While the expression and/or activity of endothelial nitric oxide synthase (eNOS) has been characterized in spontaneously hypertensive (SHR) and normotensive Wistar Kyoto rat (WKY) hearts, in coronary endothelial cells (ECs) from both strains, the effect of NO on intracellular calcium concentration ([Ca(2+)](i)) is still unknown. Coronary microvascular ECs were isolated from SHR and WKY and characterized. Immunocytochemistry and Western blot analysis showed that eNOS was similarly expressed in ECs from both strains. Measuring [Ca(2+)](i) by imaging analysis of fura-2-loaded cells, we demonstrated that alpha-thrombin (3-180 U l(-1)) induced a superimposable dose-dependent calcium transient in ECs from both strains. In WKY ECs, S-nitroso-N-acetyl-DL-penicillamine (SNAP) dose-dependently (10 - 100 microM) and 0.1 microM atrial natriuretic factor (ANF) reduced the maximum and the decay time of alpha-thrombin-induced calcium transient. The inhibitory effects of SNAP and ANF were prevented by blocking cyclic GMP-dependent protein kinase. Non selective eNOS inhibitors prolonged the decay time of alpha-thrombin-induced calcium transient, while the selective inducible NOS inhibitor 1400 W was ineffective. SNAP (100 microM) and 0.1 microM ANF increased cyclic GMP content up to 22.9 and 42.3 fold respectively. In SHR ECs, alpha-thrombin-induced calcium transient was not modified by SNAP, ANF or eNOS inhibition. SNAP (100 microM) and 0.1 microM ANF increased cyclic GMP content up to 9. 3 and 51 fold respectively. In WKY ECs, SNAP dose-dependently (10 - 100 microM) reduced also bradykinin-induced calcium transient, while in SHR ECs was ineffective. We concluded that in SHR ECs, the cyclic GMP-dependent regulation of calcium transient is lost.

The development of catalysts resistant to deactivation, especially to coke formation, is a key issue to perform ethanol reforming successfully. Aiming at carbon formation minimization, in the present work, bimetallic Pt- Ni/CeO2 catalysts were deposited on silica gel with high surface area and tested for ethanol reforming in the low temperature range (300 - 600 °C). The activity was investigated at different contact times and the impact of oxygen co-feeding on catalyst performances was also studied. The increase of space velocity had no effect on ethanol conversion at T > 420 °C under both oxidative and non-oxidative conditions; however, when O2 was co-fed, contact time growth assured almost total conversion until 300 °C. Moreover, the results of stability tests revealed that O2 addition in the reforming mixture improved catalyst stability, which was maintained for 70 h.

In the last years, the widespread diffusion of Online Social Networks (OSNs) has enabled new forms of communications that make it easier for people to interact remotely. Unfortunately, one of the first consequences of such a popularity is the increasing number of malicious users who sign-up and use OSNs for non-legit activities. In this paper we focus on spam detection, and present some preliminary results of a system that aims at speeding up the creation of a large-scale annotated dataset for spam account detection on Twitter. To this aim, two different algorithms capable of capturing the spammer behaviors, i.e., to share malicious urls and recurrent contents, are exploited. Experimental results on a dataset of about 40.000 users show the effectiveness of the proposed approach.

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.