37 research outputs found

    High performance of Au/ZTC based catalysts for the selective oxidation of bio-derivative furfural to 2-furoic acid

    Get PDF
    Abstract Furfural is a platform bio-molecule for which is valuable to develop new green upgrading processes in biorefinery. We report here for the first time the high performance of Au/ZTC catalyst for the selective oxidation of furfural to 2-furoic acid, as first step to develop electrodes. The ordered nanostructure and high surface area of BEA structure replica ZTC allows to develop 3D-type electrodes. Au/ZTC catalyst shows higher performance than commercial Vulcan, used as reference conductive carbon in fuel cells. The weak acidity on ZTC avoids decarboxylation and esterification reactions, leading to about 90% of furfural conversion fully selectivity to 2-furoic acid

    Performance of alere determine HIV-1/2 Ag/Ab combo rapid test for acute HIV infection: A case report | Performance del test rapido Alere Determine HIV-1/2 Ag/Ab Combo nell?infezione acuta da HIV: Un caso clinic

    Get PDF
    We describe a case of symptomatic acute HIV infection in a young man where a fourth-generation rapid screening test combining HIV-specific antibody and p24 antigen was negative. In highly suspicious cases of acute HIV infection, plasma HIV RNA assays together with conventional, non-rapid screening tests should be used

    The rotation - Lithium depletion correlation in the beta Pictoris association and LDB age determination

    Get PDF
    There is evidence in the 125-Myr Pleiades cluster, and more recently in the 5-Myr NGC 2264 cluster, that rotation plays a key role in the Lithium (Li) depletion processes among low-mass stars. Fast rotators appear to be less Li-depleted than equal-mass slow rotators. We intend to explore the existence of a Li depletion - rotation connection among the beta Pictoris members at an age of about 24 Myr, and to use such correlation either to confirm or to improve the age estimate based on the Lithium Depletion Boundary (LDB) modeling. We have photometrically monitored all the known members of the beta Pictoris association with at least one Lithium equivalent width (Li EW) measurement from the literature. We measured the rotation periods of 30 members for the first time and retrieved from the literature the rotation periods for other 36 members, building a catalogue of 66 members with measured rotation period and Li EW. We find that in the 0.3 < M < 0.8 Msun range, there is a strong correlation between rotation and Li EW. For higher mass stars, no significant correlation is found. For very low mass stars in the Li depletion onset, at about 0.1 Msun, data are too few to infer a significant correlation. The observed Li EWs are compared with those predicted by the Dartmouth stellar evolutionary models that incorporate the effects of magnetic fields. After decorrelating the Li EW from the rotation period, we find that the hot side of the LDB is fitted well by Li EW values corresponding to an age of 25±3 Myr in good agreement with independent estimates from the literature.Fil: Messina, S.. Catania Astrophysical Observatory; ItaliaFil: Lanzafame, A. C.. Catania Astrophysical Observatory; ItaliaFil: Feiden, G. A.. Uppsala University; SueciaFil: Millward, M.. York Creek Observatory; AustraliaFil: Desidera, S.. Osservatorio Astronomico Di Padova; ItaliaFil: Buccino, Andrea Paola. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Curtis, I.. Minor Planet Center; AustraliaFil: Jofre, Jorge Emiliano. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Departamento de Astrofísica Estelar; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Kehusmaa, P.. Harlingten Atacama Observatory; ChileFil: Medhi, B. J.. Aryabhatta Research Institute Of Observational Sciences; IndiaFil: Monard, B.. Klein Karoo Observatory; SudáfricaFil: Petrucci, Romina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Departamento de Astrofísica Estelar; Argentin

    Expression pattern of estroprogestinic receptors in sinonasal inverted papilloma

    Get PDF
    open13openSerra A; Caltabiano R; Spinato G; Gallina S; Caruso S; Rapisarda V; Di Mauro P; Castro V; Conti A; Licciardello L; Maiolino L; Lanzafame S; Cocuzza SSerra, A; Caltabiano, R; Spinato, G; Gallina, S; Caruso, S; Rapisarda, V; Di Mauro, P; Castro, V; Conti, A; Licciardello, L; Maiolino, L; Lanzafame, S; Cocuzza,

    Effect of the Nano-Ca(OH)2 addition on the Portland clinker cooking efficiency

    Get PDF
    A new technology was tested to improve the cooking efficiency of the raw mixture for Portland clinker production by the use of nano-Ca(OH)2. A decrease in the free lime concentration after the firing of approximately 35% and 55% in the nano-added clinkers burned at 1350 °C and 1450 °C, respectively, with respect to the standard Portland clinkers was observed. Moreover, in the nano-added clinkers, a slight decrease in alite (C3S), of approximately 2-4 wt%, and increase in belite (C2S), of approximately 5-6 wt%, were observed. Despite these variations, the C2S and C3S abundance lies within the ranges for standard Portland clinkers. The results showed that the nano-addition leads to an increase of the raw mixtures' cooking efficiency. The relatively low energy required for the clinker firing could be used to increase the plant productivity and decrease the CO2 emissions during clinker burning. The decrease of the work index of the clinkers produced by the use of the nano-Ca(OH)2 also contributes to the energy saving during clinker grinding. Differences were also found in the pore size distribution among nano-added clinkers and the standard Portland clinker. The smallest porosities with the modal volume lying in the class of 3 × 10-6 mm3 were found to increase by the use of nano-Ca(OH)2. However, the pore volumes higher than 2.0 × 10-5 mm3 decreased in the nano-added clinkers. © 2019 by the authors

    persistent occurrence of serogroup y sequence type st 23 complex invasive meningococcal disease among patients aged five to 14 years italy 2007 to 2013

    Get PDF
    In Italy, the incidence of invasive meningococcal disease (IMD) has remained stable since 2007 (around 0.3 cases/100,000 inhabitants). However, as reported for other European countries, an increase of serogroup Y Neisseria meningitidis has been observed. In this study we report IMD cases from 2007 to 2013 in Italy and investigate the clinical and epidemiological features of cases affected by serogroup Y. Molecular characteristics of serogroup Y strains are also described. During the study period, the proportion of IMD cases due to serogroup Y increased, ranging from 2% in 2007 to 17% in 2013 (odds ratio (OR): 8.8), whereby the five to 14 years age group was mostly affected (p < 0.001). Overall 81 serogroup Y IMD cases were identified, with a median age of 18 years, ranging from three months to 84 years. Of the 81 respective patient samples, 56 were further subject to molecular typing. The sequence type (ST)-23 complex (clonal complex (cc)23) was predominant among serogroup Y meningococci (54/56 samples), and included nine different STs. Presumably, ST-23 was the founding genotype, with all the other STs presenting as single-locus variants. All cc23 isolates analysed harboured mutations in the lpxL1 gene; however, no associations among lpxL1 mutations, ST and age group were identified. Overall, these findings generate scientific evidence for the use of the quadrivalent meningococcal conjugate vaccine in the five to 14 years age group

    Gaia Early Data Release 3: Structure and properties of the Magellanic Clouds

    Get PDF
    We compare the Gaia DR2 and Gaia EDR3 performances in the study of the Magellanic Clouds and show the clear improvements in precision and accuracy in the new release. We also show that the systematics still present in the data make the determination of the 3D geometry of the LMC a difficult endeavour; this is at the very limit of the usefulness of the Gaia EDR3 astrometry, but it may become feasible with the use of additional external data. We derive radial and tangential velocity maps and global profiles for the LMC for the several subsamples we defined. To our knowledge, this is the first time that the two planar components of the ordered and random motions are derived for multiple stellar evolutionary phases in a galactic disc outside the Milky Way, showing the differences between younger and older phases. We also analyse the spatial structure and motions in the central region, the bar, and the disc, providing new insights into features and kinematics. Finally, we show that the Gaia EDR3 data allows clearly resolving the Magellanic Bridge, and we trace the density and velocity flow of the stars from the SMC towards the LMC not only globally, but also separately for young and evolved populations. This allows us to confirm an evolved population in the Bridge that is slightly shift from the younger population. Additionally, we were able to study the outskirts of both Magellanic Clouds, in which we detected some well-known features and indications of new ones

    The Gaia mission

    Get PDF
    Gaia is a cornerstone mission in the science programme of the EuropeanSpace Agency (ESA). The spacecraft construction was approved in 2006, following a study in which the original interferometric concept was changed to a direct-imaging approach. Both the spacecraft and the payload were built by European industry. The involvement of the scientific community focusses on data processing for which the international Gaia Data Processing and Analysis Consortium (DPAC) was selected in 2007. Gaia was launched on 19 December 2013 and arrived at its operating point, the second Lagrange point of the Sun-Earth-Moon system, a few weeks later. The commissioning of the spacecraft and payload was completed on 19 July 2014. The nominal five-year mission started with four weeks of special, ecliptic-pole scanning and subsequently transferred into full-sky scanning mode. We recall the scientific goals of Gaia and give a description of the as-built spacecraft that is currently (mid-2016) being operated to achieve these goals. We pay special attention to the payload module, the performance of which is closely related to the scientific performance of the mission. We provide a summary of the commissioning activities and findings, followed by a description of the routine operational mode. We summarise scientific performance estimates on the basis of in-orbit operations. Several intermediate Gaia data releases are planned and the data can be retrieved from the Gaia Archive, which is available through the Gaia home page. http://www.cosmos.esa.int/gai

    Optimisation of the electrochemical conversion of CO2 into formate in a flow cell configuration using a bismuth-based electrocatalyst

    Get PDF
    Highly selective and active electrocatalysts are essential for industrial application of the electrochemical conversion of CO2 into valuable products. The electrochemical cell configuration and the optimisation of its parameters are also of paramount importance to promote the conversion of CO2 and enhance the selectivity and stability of the electrocatalyst. Furthermore, the cell needs to be designed to enable the continuous conversion of CO2 in a flow cell configuration with optimal use of energy resources, to obtain a sustainable CO2-to-formate conversion process. In this work, we present an in-depth, systematic investigation of the crucial parameters for the optimum operation of a flow cell for the conversion of CO2 with a highly scalable Bi-based electrocatalyst at industrially-relevant current densities (j = 100 mA cm−2), achieving high Faradaic efficiency (FEformate > 70%) for a prolonged application time (t = 65 h). By studying and tuning the electrolyte and CO2 feed flow, the membrane configuration, the pH of the electrolyte and the effect of possible contaminants in the CO2 source, we were able to gain important insights into the large-scale application of the Bi-based electrocatalyst for the electrochemical reduction of CO2 into formate

    Water Thermodynamics and Its Effects on the Protein Stability and Activity

    No full text
    We discuss a phenomenon regarding water that was until recently a subject of scientific interest: i.e., the dynamical crossover, from the fragile to strong glass forming material, for both bulk and protein hydration water. Such crossover is characterized by a temperature TL in which significant dynamical changes like the decoupling (or the violation of the Stokes-Einstein relation) of homologous transport parameters, e.g., the density relaxation time τ and the viscosity η, occur in the system. On this respect we considered the dynamic properties of water-protein systems. More precisely, we focused our study on proteins and their hydration water, as far as bulk and confined water. In order to clarify the effects of the water dynamical crossover on the protein properties we considered and discussed in a comparative way previous and new experimental data, obtained from different techniques and molecular dynamic simulation (MD). We pointed out the reasons for different dynamical findings from the use of different experimental techniques
    corecore