Fast arbitrary geodesic computation on triangular meshes

We propose a method to accelerate the computation of geodesic over triangular meshes. The method is based on a precomputation step that allows to store arbitrary complex distance metrics and a query step where we employ a modified version of the bidirectional A* algorithm. We show how this method is significantly faster then the classical Dijkstra algorithm for the computation of point to point distance. Moreover, as we precompute the exact geodesic, it achieves better accuracy

Silica-based mesoporous materials as drug delivery system for methotrexate release.

Antineoplastic methotrexate has been loaded through different soaking procedures on silica-based mesoporous materials and, successively, released mimicking an oral administration. The materials were prepared using a self-assembly mechanism in the presence of cationic surfactants with alkyl chain of 16, 12, and 10 carbon atoms in the synthesis mixture to obtain different pore diameter in the porous structure. Mesoporous materials were prepared as pure silica sample and in the presence of Al(OH)(3) in the synthesis mixture. Only alumina-silica samples were able to load methotrexate. The amounts of drug loaded and the in vitro release kinetics are a function of the pore size of the materials

Nanostructured Ni-Fe-P Alloy for Alkaline Electrolyzer

In recent years, the interest towards green hydrogen has drastically increased due to the global decarbonization process. Electrochemical water splitting is considered an attractive solution to convert and store the surplus energy from renewable energy sources. However, hydrogen production by water electrolysis is not economically sustainable. To reduce the cost of produced hydrogen, it is necessary to switch from noble-metal catalyst (Pt, Pd…) to cheap alternatives with a lower per unit energy cost but at the same time able to guarantee a high electrocatalytic activity for both oxygen and hydrogen evolution reactions. Among transition metals, nickel was selected as active material for its low cost and high chemical stability in alkaline media. Currently, the most investigated transition metal catalyst includes alloy of nickel with sulfide, phosphide, and nitride. In this work, a ternary alloy of Nickel-Iron-Phosphorus with nanowires morphology was investigated and compared to the binary alloy of Nickel-Iron. Ni-Fe-P NWs electrodes were obtained by potential-controlled pulse electrochemical deposition using polycarbonate membrane as template. Electrodes morphology and structure were studied by scanning electrode microscopy (SEM), energy diffraction spectroscopy (EDS) and X-ray diffraction (XRD). Electrodes were tested both as cathodes as anodes by Quasi Steady State Polarization (QSSP) and Galvanostatic Test. All the tests were performed in 30% w/w KOH aqueous solution at room temperature. Preliminary results showed better performance of the ternary alloy compared to the binary one

Ni-Fe-S alloy nanostructured electrodes for alkaline electrolyser

In recent years, renewable energy sources are becoming more and more relevant owing to the progressive decarbonization of energy processes to reduce CO2 emissions [1,2]. In this view, worldwide public authorities are encouraging the use of renewable energies by promoting laws and guidelines [3,4]. One of the main drawbacks of renewable sources is their unpredictability, consequently, interest in green hydrogen has drastically increased. One way to produce green hydrogen is by water electrolysis using only electricity from renewable sources. It is a viable strategy to take advantage of the surplus electricity from them. The most relevant part of the cost of electrochemical hydrogen comes from the electricity cost and catalysts. For this reason, research is focused on improving the performance of the electrolyzer, using more efficient and less expensive materials, such as transition metal alloys like Nickel-based alloy [5]. One way to improve the performance of electrolyzers is based on the development of nanostructured electrodes distinguishing for low cost and high electrocatalytic activity. The proposed technique for fabricating the electrodes is known as template electrosynthesis. The template used is a commercial porous polycarbonate membrane (PMC - Whatman, Cyclopore, 20 μm thick), which due to its morphology allows the formation of nanowire-shaped nanostructures, highly interconnected with each other, which have the advantage of possessing a high surface area (about two orders of magnitude higher than planar electrode with the same geometric area). To make the membrane conductive, a gold film of thickness around 20-30 nm is deposited on one of the template surfaces by a sputtering process. After sputtering, a compact nickel layer of thickness around 20 μm is electrodeposited on the gold side. This, in addition to ensuring adequate mechanical strength to the electrode, acts as a current collector. After the electrodeposition of the nickel collector, the next step is the electrodeposition of the NWs formed inside the template pores. In previous works, we have fabricated Ni nanowires by template electrosynthesis, featuring by very high surface area. Starting from the best-performing nickel-iron alloy previously studied [6], this work focuses on the fabrication of nickel-iron-sulfur electrodes. In an aqueous solution containing nickel and iron, a third element is added in different concentrations in order to obtain electrodes with different compositions. The chemical and morphological features of these nanostructured electrodes are carried out through scanning electrode microscopy (SEM) and energy diffraction spectroscopy (EDS) analyses, and those results will be presented and discussed. Subsequently, electrochemical and electrocatalytic tests (Cyclic Voltammetry (CV), Quasi Steady State Polarization (QSSP) and Galvanostatic Step) are carried to establish the best alloy composition and they are carried out for both hydrogen and oxygen evolution reactions. Then, a long-term test conducted at a constant current density in an aqueous solution of potassium hydroxide (30% w/w) will also be reported

Fabrication of Ni-alloy nanostructured elecrodes for alkaline electrolizers

In last years, renewable energy sources are becoming more and more important owing to the progressive decarbonization of energy processes to reduce CO2 emissions [1,2]. In this view, governments and authorities all around the world are encouraging the use of renewable energies by promoting laws and initiatives for the most sustainable energy transition [3,4]. One of the main drawbacks of renewable sources is their unpredictability, consequently, interest in hydrogen has drastically increased. One way to produce green hydrogen is by water electrolysis using only electricity from renewable sources. It is a viable strategy to take advantage of the surplus electricity. The most relevant part of the cost of electrochemical hydrogen comes from the electricity cost and catalysts. For this reason, research is focused on improving the performance of the electrolyzer, using more efficient and less expensive materials, such as transition metal alloys like Nickel-based alloy [5]. One of the possible ways to improve the performance of electrolyzers is based on the development and fabrication of nanostructured electrodes with a low cost and high electrocatalytic activity. In previous works, Ni nanowires were fabricated by template electrosynthesis, featuring by very high surface area. Starting from the best-performing nickel-iron alloy previously studied [6], this work focuses on the fabrication of nickel-iron-sulfur electrodes. In an aqueous solution containing nickel and iron, a third element was added in different concentrations in order to obtain electrodes with different compositions. The chemical and morphological features of these nanostructured electrodes were studied through scanning electrode microscopy (SEM) and energy diffraction spectroscopy (EDS) analyses, and those results will be presented and discussed. Electrochemical and electrocatalytic tests (Cyclic Voltammetry (CV), Quasi Steady State Polarization (QSSP) and Galvanostatic Step) were carried out to establish the best alloy composition for both hydrogen and oxygen evolution reactions. Long-term tests performed at a constant current density in an aqueous solution of potassium hydroxide (30% w/w) will be also reported. Acknowledgments This research was funded by CNMS, Centro Nazionale per la Mobilità sostenibile (MUR, PNRR-M4C2, CN00000023), spoke 12 – innovative propulsion. References [1] A.T.D. Perera, R.A. Attalage, K.K.C.K. Perera, V.P.C.Dassanayake, “Designing standalone hybrid energy systems minimizing initialinvestment, life cycle cost and pollutant emission” Energy, 54, 2013, 237-248. [2] K. Bandara, T. Sweet, J. Ekanayake, “Photovoltaic applications for off-grid electrification using novel multi-level inverter technology with energy storage”, Renewable Energy, 37, 2012, 82-88 [3] P. Balcombe, D. Rigby, A. Azapagic, “Motivations and barriers associated with adopting microgeneration energy technologies in the UK”, Renewable and Sustainable Energy Reviews, 22, 2013, 655-666. [4] H. Meyar-Naimi, S. Vaez-Zadeh, “Sustainable development-based energy policy making frameworks, a critical review”, Energy Policy, 43, 2012, 351-361. [5] F. Safizadeh, E. Ghali, G. Houlachi, “Electrocatalysis developments for hydrogen evolution reaction in alkaline solutions – A Review”, International Journal of Hydrogen Energy, 40, 2015, 256–274. [6] B. Buccheri, F. Ganci, B. Patella, G. Aiello, P. Mandin, R. Inguanta, “Ni-Fe alloy nanostructured electrodes for water splitting in alkaline electrolyser”, Electrochimica Acta, Volume 388, 2021, 0013-4686

Performance of Nickel-Iron nanostructured electrodes at different temperatures

In recent years, the whole world has been trying to reduce CO2 emissions through the global decarbonization of energy processes. In this view, the interest towards green hydrogen has drastically increased. One way to produce green hydrogen is by water electrolysis using only electricity from renewable sources. The storage of renewable solar or wind electricity is a major challenge to build a sustainable future energy system. The electrochemical production of hydrogen, through electrolysers, is a viable strategy to take advantage of the surplus electricity coming from renewable energy sources. Its production is pollution-free but is not economically viable. The development of more efficient electrolysers with low-cost electrode materials plays a key role. Catalysts must have such as good electrocatalytic properties, high conductivity, high availability, low cost, and good chemical stability. Nowadays, research is focused on improving the Alkaline Water Electrolysis (AE) to reduce the cost of electrode production. In alkaline environment it was demonstrated that, transition metals, and in particular Nickel or nickel based alloy nanostructured electrodes, have good and stable performances. Furthermore, industrial alkaline electrolysers work at temperatures between 40 and 90°C. Therefore, electrodes must be mechanically and chemically stable at these temperatures. An approach to improve AE performance consists on the fabbrication of nanostructured electrodes because they are characterized by high electrocatalytic activity due to the very high surface area. Starting from the results obtained in a previous work, the nanostructured alloy of NiFe was tested both as cathode and anode at three different temperatures (25 °C, 40 °C, 60 °C). Nanostructured electrodes were obtained through a simple and cheap method, template electrosynthesis, using a polycarbonate membrane as a template. NiFe electrodes morphology was studied by scanning electrode microscopy (SEM) and their composition was evaluated by energy diffraction spectroscopy (EDS) analyses. Later, the electrodes were characterized using various electrochemical techniques: Cyclic Voltammetry (CV), Quasi Steady State Polarization (QSSP) and Galvanostatic Step. To evaluate the mid-term behavior of the electrodes, especially at high temperatures, a constant current density was applied for 6 hours. In particular, -50 mA cm-2 for Hydrogen Evolution Reaction (HER) and 50 mA cm-2 for Oxygen Evolution Reaction (OER). All the tests were performed in 30% w/w KOH aqueous solution. Temperature increase plays a key role in increasing the efficiency of both anode and cathode reactions. As expected, the best result was obtained at 60 °C. Acknowledgments This research was funded by MUR, CNMS Centro Nazionale per la Mobilità sostenibile grant number CN0000002

Th17-Gene Expression Profile in Patients with Chronic Venous Disease and Venous Ulcers: Genetic Modulations and Preliminary Clinical Evidence

Chronic venous disease is a condition globally widespread, resulting in a disabling pathological disorder. The CD4 + Th17+ (Cluster Differentiation 4) lymphocytes represent a regulative factor for innate immunity related to the development of complex diseases. Recently, these mechanisms have been associated with vascular disease. The aim of this work is to validate whether the Th17 response correlates with the development of CVI (Chronic venous insufficiency)and CVLUs (chronic venous limbs ulcers) and whether Th17 markers can be used, both as intrinsic risk factors and diagnostic markers, for disease development. PBL derived from peripheral blood samples of patients and controls were subjected to gene expression analysis for IL23R, IL17, SGK1, TGFβ, RORγ, FOXO1, and RANBP1 by qRT-PCR and immunoblot. A post hoc correlation, the diagnostic performance of the target genes, and multivariable analyses were properly conducted. The main expression markers of the CD4 + Th17+ switch were strongly activated in chronic venous insufficiency and in advanced ulceration. The correlation analysis demonstrated the inter-dependence on Th17’s signature modulation. ROC (Receiver Operating Characteristic) analysis defined, for the examined genes, a clinical value as the potential diagnostic markers. Multi-logistic regression studies showed that Th17 markers behave as empirical risk factors for CVD (chronic venous disease) development. Taken together, the present data provide a new hypothesis for the TH17-dependent pathogenesis of CVD, favoring the possibility for the development of new diagnostic, preventive, and therapeutic approaches

Experimental investigation of classical and quantum correlations under decoherence

It is well known that many operations in quantum information processing depend largely on a special kind of quantum correlation, that is, entanglement. However, there are also quantum tasks that display the quantum advantage without entanglement. Distinguishing classical and quantum correlations in quantum systems is therefore of both fundamental and practical importance. In consideration of the unavoidable interaction between correlated systems and the environment, understanding the dynamics of correlations would stimulate great interest. In this study, we investigate the dynamics of different kinds of bipartite correlations in an all-optical experimental setup. The sudden change in behaviour in the decay rates of correlations and their immunity against certain decoherences are shown. Moreover, quantum correlation is observed to be larger than classical correlation, which disproves the early conjecture that classical correlation is always greater than quantum correlation. Our observations may be important for quantum information processing.Comment: 7 pages, 4 figures, to appear in Nature Communication

Nanostructured Ni-Fe-S Based Electrode for Hydrogen Production by Water Electrolysis

Green hydrogen is a real alternative to change the current energy system. Electrochemical water splitting is considered an attractive solution to convert and store the surplus of renewable energy sources. However, hydrogen production by water electrolysis is not economically sustainable due to the use of high noble metals as catalysts (generally platinum or palladium). In order to reduce costs, in this work we have synthesized a ternary alloy of nickel, iron and sulfur and used it as the cathode in an alkaline electrolyzer to produce hydrogen from water. Furthermore, to increase the features of the proposed alloy, this material was synthesized into the pore of a polycarbonate membrane to obtain a nanostructured electrode that exposes a very high surface area to the solution and consequently a large number of electrocatalytic active sites. The electrode fabrication was carried out by potential-controlled pulsed electrochemical deposition where the potential switch from -0.45 V to -1.3 V vs. SCE for 60 cycles. The electrode was characterized by SEM and EDS showing the nanostructured nature and the composition of the electrode. Then it was tested as the cathode in an alkaline electrolyzer (30% KOH) at room temperature. Preliminary results show that the addition of sulfur to the alloy permits to increase in the electrode features compared to the binary alloy of nickel and iron

HLA and killer cell immunoglobulin-like receptor (KIRs) genotyping in patients with acute viral encephalitis

Introduction: The HLA genes, as well as the innate immune KIR genes, are considered relevant determinants of viral outcomes but no study, to our knowledge, has evaluated their role in the clinical setting of acute viral encephalitis. Results: Subjects with acute viral encephalitis in comparison to subjects without acute viral encephalitis showed a significantly higher frequency of 2DL1 KIR gene and AA KIR haplotypes and of HLA-C2 and HLA-A-Bw4 alleles. Subjects without acute viral encephalitis showed a higher frequency of interaction between KIR2DL2 and HLAC1. Multiple logistic regression analysis showed the detrimental effect of HLA-A haplotype and HLA-C1, HLA-A-BW4 HLA-B-BW4T alleles, whereas multiple logistic regression showed a protective effect of AB+BB KIR haplotype and a detrimental effect of interaction between KIR3DL1 and HLA-A-Bw4. Discussion: Our findings of a lower frequency of activating receptors in patients with acute encephalitis compared to controls could result in a less efficient response of NK cells. This finding could represent a possible pathogenetic explanation of susceptibility to acute symptomatic encephalitis in patients with viral infection from potentially responsible viruses such as Herpes virus. Materials and Methods: 30 Consecutive patients with symptomatic acute viral encephalitis and as controls, 36 consecutive subjects without acute encephalitis were analyzed. The following KIR genes were analyzed, KIR2DL1, 2DL2, 2DL3, 2DL5, 3DL1, 3DL2, 3DL3, 2DL4, 2DS1, 2DS2, 2DS3, 2DS4, 2DS5, 3DS1, 2 pseudogenes (2DP1 and 3DP1) and the common variants of KIR2DL5 (KIR2DL5A, KIR2DL5B)