Hydrogen dissociation on the Mg(0001) surface from quantum Monte Carlo calculations

We have used diffusion Monte Carlo (DMC) simulations to calculate the energy barrier for H$_2$ dissociation on the Mg(0001) surface. The calculations employ pseudopotentials and systematically improvable B-spline basis sets to expand the single particle orbitals used to construct the trial wavefunctions. Extensive tests on system size, time step, and other sources of errors, performed on periodically repeated systems of up to 550 atoms, show that all these errors together can be reduced to $\sim 0.03$ eV. The DMC dissociation barrier is calculated to be $1.18 \pm 0.03$ eV, and is compared to those obtained with density functional theory using various exchange-correlation functionals, with values ranging between 0.44 and 1.07 eV.Comment: 6 pages, 4 figures, to appear in Physical Review

The discovery of a low mass, pre-main-sequence stellar association around gamma Velorum

We report the serendipitous discovery of a population of low mass, pre-main sequence stars (PMS) in the direction of the Wolf-Rayet/O-star binary system gamma^{2} Vel and the Vela OB2 association. We argue that gamma^{2} Vel and the low mass stars are truly associated, are approximately coeval and that both are at distances between 360-490 pc, disagreeing at the 2 sigma level with the recent Hipparcos parallax of gamma^{2} Vel, but consistent with older distance estimates. Our results clearly have implications for the physical parameters of the gamma^{2} Vel system, but also offer an exciting opportunity to investigate the influence of high mass stars on the mass function and circumstellar disc lifetimes of their lower mass PMS siblings.Comment: Monthly Notices of the Royal Astronomical Society, Letters - in pres

Hydrogen Dissociation and Diffusion on Ni and Ti -doped Mg(0001) Surfaces

It is well known, both theoretically and experimentally, that alloying MgH$_2$ with transition elements can significantly improve the thermodynamic and kinetic properties for H$_2$ desorption, as well as the H$_2$ intake by Mg bulk. Here we present a density functional theory investigation of hydrogen dissociation and surface diffusion over Ni-doped surface, and compare the findings to previously investigated Ti-doped Mg(0001) and pure Mg(0001) surfaces. Our results show that the energy barrier for hydrogen dissociation on the pure Mg(0001) surface is high, while it is small/null when Ni/Ti are added to the surface as dopants. We find that the binding energy of the two H atoms near the dissociation site is high on Ti, effectively impeding diffusion away from the Ti site. By contrast, we find that on Ni the energy barrier for diffusion is much reduced. Therefore, although both Ti and Ni promote H$_2$ dissociation, only Ni appears to be a good catalyst for Mg hydrogenation, allowing diffusion away from the catalytic sites. Experimental results corroborate these theoretical findings, i.e. faster hydrogenation of the Ni doped Mg sample as opposed to the reference Mg or Ti doped Mg.Comment: 17 pages, 15 figures, to appear in Journal of Chemical Physic

Philosophie et Innovation culturelle

This paper is about innovation, reflection, and inclusion. The argument starts with a general thesis on philosophy and innovation. The pages on communities of practice continue the argument by embodying the reflective stance in consideration of societal readiness and cultural innovation. The argument includes a comprehensive presentation of key performance indicators for research infrastructures dealing with content and processes of cultural innovation. A few words on the role of the reflective society wrap up the paper. Evaluation of Social Sciences and Humanities in Europe. Hcéres Colloquium Proceedings - Paris IAS, 16-17 May

Descripción Sensorial Cuantitativa de la Miel de Acacia

En este trabajo se describen las características sensoriales de la miel de acacia. La descripción sensorial cuantitativa fue realizada por un panel, previamente seleccionado y entrenado de acuerdo al procedimiento establecido en IRAM 20005, constituido por cinco hombres y cuatro mujeres de edades comprendidas entre 20 y 30 años, pertenecientes a la comunidad académica de la UTN FRRo. Una vez garantizado el desempeño de los miembros del panel, se realizó el análisis descriptivo de dicha miel, en condiciones controladas de laboratorio. Los atributos analizados fueron intensidad del olor y del color, aroma, fluidez, dulzor, granulosidad, persistencia, cantidad y tamaño de cristales. Las mieles de acacia presentaron dulzor entre moderado e intenso, color ámbar claro sin notas características, olor moderado con notas vegetales, cálidas y florales, mientras que la persistencia resultó entre baja y media. El perfil obtenido contribuye a caracterizar la miel en relación a su origen floral, constituyendo una herramienta de diferenciación, que aumenta su valor agregado a la hora de comercializarl

FORCE- AND POWER-TIME RELATIONSHIP,EMG RESPONSES IN CONCENTRIG AND ISOMETRIC CONDITIONS,EFFECTS OF TRAINING AND INDIVIDUAL CRARACTERISTICS

Introduction The relationship between EHG (temporal pattern, IEMG, power spectra ) and the biomechanical parameter in isometric and dynamic muscle tension represents an essential method in the analysis of the specificity of training effects and of the individual characteristics in motor control modelling and in practical motor learning. METHODS Force-time, power-time relationships under concentric and isometric conditions (MVC) with and without preloading were determined. For EHG purpose, surface electrodes (O= 5 mm; interelectrode distance 40 mm) were placed over the belly of each muscle (Tric.br.;Bic.br.; Delt.an.; Pect.ma.). Bipolar myoelectrical potentials were recorded with the passive electrode placed between the two actives: signals were preamplified and band-pass filtered (CMRRT 70 db, BP= 10 Hz- 1 KHz: Zin=1,5 MR. gain= 1000). EMG signals and the force were digitized on-line with a sampling frequency of 1000 Hz. For time structure analysis EMG signals were full-wave rectified and bandpass filtered (20-70 Hz) to obtain envelop curve patterns of each muscle. Power spectra analysis (median frequency MF) were performed using 1024 and pl2 data points. 3 groups (n=4) of sport students were involved in the investigation. Subjects performed a 8 week training period under different loading conditions. RESULTS # In the concentric tasks subjects show individual strategies in the muscular coordination patterns dependent on the load intensity. # Differences in the muscular interactivity pattern are not necessarily matching similar variation in the mechanical output. # For increasing loads there is a linear relationship between muscular activation level and mechanical power output. # In the power spectra, trends are consistent but also discontinuous. Median frequency could possibly indicate that some subjects have resources in motor units recruitment . # Other considerations are discussed referring to the muscular activation and the isometric MVC under preloading conditions

Quality of life in children with adverse drug reactions: A narrative and systematic review

Aims Adverse drug reactions are a common problem affecting adults and children. The economic impact of the adverse drug reactions has been widely evaluated; however, studies of the impact on the quality of life of children with adverse drug reactions are scarce. The aim was to evaluate studies assessing the health-related quality of life of children with adverse drug reactions. Methods We conducted a systematic review that included the following electronic databases: MEDLINE, EMBASE and the Cochrane Library (including the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects, the Cochrane Controlled Trials Register and the Health Technology Assessment Databases). Results Nine studies were included. Four of the studies were conducted in children with epilepsy; the rest of them involved children with chronic viral hepatitis, Crohn\u27s disease, paediatric cancer and multiple adverse drug reactions compared with healthy children. Based on their findings, authors of all studies concluded that adverse drug reactions had a negative impact on the quality of life of children. No meta-analysis was conducted given the heterogeneous nature of the studies. Conclusions To date, there is no specific instrument that measures quality of life of children with adverse drug reactions, and the information available is poor and variable. In general, adverse drug reactions have a negative impact on the quality of life of affected children. For those interested in this area, more work needs to be done to improve tools that help to evaluate efficiently the health-related quality of life of children with adverse drug reactions and chronic diseases

The Dynamics of the Innovation System for Functional Foods in South Brazil

 This study aims at identifying the dynamics of the innovation system for functional foods (FF) in Rio Grande do Sul, Brazil. Functional food is any healthy food claimed to have a health-promoting or disease-preventing property beyond the basic function of supplying nutrients. Health has been named as the most significant trend and innovation driver in the global food and drinks market. Brazil is one of the leading countries in food production and consumption, and the market for functional foods have been growing 10% per year, three times more than the market for conventional foods. Although this food category is considered mature in some developed markets (such as in Japan, in the Nordic countries and in the U.S), it is still unknown for many consumers, especially those located in developing countries. On the other hand, functional foods has been attracting the attention of multinationals and local food industries, since innovation can significantly impact on their competitive advantages. Therefore, in this study, first we are going to investigate consumers’ motivations, attitudes and intention to buy functional foods, since the market demands a better understanding of this trend. A survey with 450 consumers was conducted and provided quantitative insights. Secondly, we identified the availability of functional food products in the local retail market, through observation techniques. Our aim was to confront consumers’ needs with local food companies’ market supply. In a further stage, we are going to analyse the functioning of this innovation system, describing the agents involved in this context and their relations through in-depth interviews with local representatives (stakeholders). Innovation system is here understood as the set of distinct institutions which jointly and individually contribute to the development and diffusion of new technologies and which provides the framework within which governments form and implement policies to influence the innovation process. As such "it is a system of interconnected institutions to create, store and transfer the knowledge, skills and artefacts which define new technologies." (Metcalfe, 1995). Hence, we are investigating issues such as: Are local food companies ready to innovate in such a competitive and dynamic scenario? How can this system respond to consumers’ demands? Are there conditions for an innovative food network in South Brazil? Our contributions help to shed light into these questions. Preliminary results indicate that the innovation system for functional foods in Rio Grande do Sul is incipient, but it is developing fast. Stronger governance and co-ordination strategies are needed. There are few local functional food products in the market, but those are attractive to consumers and indicate promising opportunities. The survey shows that interviewed consumers presented positive attitudes towards functional foods and enough purchasing power to buy it. Nutritionists and other health professionals have high credibility and could help inform consumers about the benefits of particular categories of functional foods. Food industry itself is not regarded as the most trustworthy source. Finally, this study shows that the understanding of Brazilian consumers is fundamental to help food companies define their strategies. To map the most accepted categories of functional foods is also important, aiming to avoid the "tentative and error" approach

Data-driven Models for Advanced Control of Acid Gas Treatment in Waste-to-energy Plants

This paper presents a study of identification and validation of data-driven models for the description of the acid gas treatment process, a key step of flue gas cleaning in waste-to-energy plants. The acid gas removal line of an Italian plant, based on the injection of hydrated lime, Ca(OH)2, for the abatement of hydrogen chloride, HCl, is investigated. The final goal is to minimize the feed rate of reactant needed to achieve the required HCl removal performance, also reducing as a consequence the production of solid process residues. Process data are collected during dedicated plant tests carried out by imposing Generalized Binary Noise (GBN) sequences to the flow rate of Ca(OH)2. Various input-output and state-space models are identified with success, and related model orders are optimized. The models are then validated on different datasets of routine plant operation. The proposed modeling approach appears reliable and promising for control purposes, once implemented into advanced model-based control structures

A new ⁶⁸Ga-labeled somatostatin analog containing two iodo-amino acids for dual somatostatin receptor subtype 2 and 5 targeting.

Somatostatin receptor (SST) targeting, specifically of the subtype 2 (SST2), with radiolabeled somatostatin analogs, is established for imaging and treatment of neuroendocrine tumors. Owing to the concomitant and heterogeneous expression of several subtypes on the same tumor, analogs targeting more subtypes than SST2 potentially target a broader spectrum of tumors and/or increase the uptake of a given tumor. The analog ST8950 ((4-amino-3-iodo)-D-Phe-c[Cys-(3-iodo)-Tyr-D-Trp-Lys-Val-Cys]-Thr-NH <sub>2</sub> ), bearing 2 iodo-amino acids, exhibits sub-nanomolar affinity to SST2 and SST5. We report herein the development and preclinical evaluation of DOTA-ST8950 labeled with <sup>68</sup> Ga, for imaging SST2- and SST5-expressing tumors. Comparative in vitro and in vivo studies were performed with the de-iodinated DOTA-ST8951 ((4-amino)-D-Phe-c[Cys-Tyr-D-Trp-Lys-Val-Cys]-Thr-NH <sub>2</sub> ) and with the reference compounds DOTA-TATE (SST2 selective) and DOTA-NOC (for SST2 and SST5). Compared with <sup>nat</sup> Ga-DOTA-NOC, <sup>nat</sup> Ga-DOTA-ST8950 exhibited higher affinity to SST2 and SST5 (IC <sub>50</sub> (95%CI), nM = 0.32 (0.20-0.50) and 1.9 (1.1-3.1) vs 0.70 (0.50-0.96) and 3.4 (1.8-6.2), respectively), while <sup>nat</sup> Ga-DOTA-ST8951 lost affinity for both subtypes. <sup>nat</sup> Ga-DOTA-ST8950 had the same potency for inducing SST2-mediated cAMP accumulation as <sup>nat</sup> Ga-DOTA-TATE and slightly better than <sup>nat</sup> Ga-DOTA-NOC (EC <sub>50</sub> , nM = 0.46 (0.23-0.92) vs 0.47 (0.15-1.5) vs 0.59 (0.18-1.9), respectively). [ <sup>67</sup> Ga]Ga-DOTA-ST8950 had a similar internalization rate as [ <sup>67</sup> Ga]Ga-DOTA-NOC in SST2-expressing cells (12.4 ± 1.6% vs 16.6 ± 2.2%, at 4 h, p = 0.0586). In vivo, [ <sup>68</sup> Ga]Ga-DOTA-ST8950 showed high and specific accumulation in SST2- and SST5-expressing tumors, comparable with [ <sup>68</sup> Ga]Ga-DOTA-NOC (26 ± 8 vs 30 ± 8 %IA/g, p = 0.4630 for SST2 and 15 ± 6 vs 12 ± 5 %IA/g, p = 0.3282, for SST5, 1 h p.i.) and accumulation in the SST-positive tissues, the kidneys and the liver. PET/CT images of [ <sup>68</sup> Ga]Ga-DOTA-ST8950, performed in a dual HEK-SST2 and HEK-SST5 tumor xenografted model, clearly visualized both tumors and illustrated high tumor-to-background contrast. [ <sup>68</sup> Ga]Ga-DOTA-ST8950 reveals its potential for PET imaging SST2- and SST5-expressing tumors. It compares favorably with the clinically used [ <sup>68</sup> Ga]Ga-DOTA-NOC in terms of tumor uptake; however, its uptake in the liver remains a challenge for clinical translation. In addition, this study reveals the essential role of the iodo-substitutions in positions 1 and 3 of [ <sup>68</sup> Ga]Ga-DOTA-ST8950 for maintaining affinity to SST2 and SST5, as the de-iodinated [ <sup>68</sup> Ga]Ga-DOTA-ST8951 lost affinity for both receptor subtypes