SDCS quantum mechanical flux formula revisited for electron-hydrogen ionization

Through a simple, classical, energy conservation analysis, we propose a fi-nite distance reinterpretation of the standard energy fraction definition used for the electron-hydrogen S wave ionization process. The energy modification is due to the fact that, at finite distances from the nucleus, the continuum electrons have to over-come the remaining potential energy to be completely free. As a consequence, the flux formula for extracting - at finite distances - single differential cross sections (SDCS) is also modified. Differently from the usual observations, the proposed corrections yield finite and well behaved SDCS values also at the asymmetrical situation where one of the continuum electrons carries all the energy while the other has zero energy. Re-sults of calculations performed at various impact energies, for both singlet and tripletsymmetry, are presented and compared favorably with benchmark theoretical data. Although we do not know how, we believe that finite distance effects should strongly affect the evaluation of the flux and consequently the SDCS, also in the full electron-hydrogen case.Fil: Ancarani, L. U.. Université de Lorraine; FranciaFil: Randazzo, Juan Martin. Comisión Nacional de Energí­a Atómica. Gerencia del Area Investigación y Aplicaciones No Nucleares. Gerencia de Física (Centro Atómico Balseiro). División Colisiones Atómicas; Argentin

Value Added of Resistant Starch Maize-Based Matrices in Breadmaking: Nutritional and Functional Assessment

The ability of white (W) and yellow (Y) maize flour as basic ingredients to make nutritious and healthy breads meeting functional and sensory standards is investigated. Resistant starch (R) and common wheat flour (WF) were incorporated into formulations as single and associated extra ingredients, and dough machinability, bread nutritional and functional profiles, starch hydrolysis kinetics and keeping behaviour were assessed in blended maize matrices and compared with the maize and wheat flour counterparts. Simultaneous replacement of maize flour samples by R and WF at 40 % significantly modified textural profile, crumb grain features and firming kinetics, and free polyphenol pattern of breads thereof compared to the respective Y or W maize counterparts. Bigger specific volume (+28 % Y-R-WF, +36 % W-R-WF), softer crumb bread (−64 % Y-R-WF, W-R-WF), more aerated structure and homogeneous crumb grain, and lower and slower staling kinetics are observed in composite Y and W maize-based breads, respectively. Nutritional information on maize-based blended breads showed most appealing nutritional quality than WF breads, in terms of lower digestible starch (up to −21 % in Y-R-WF, W-R-WF, WR) and rapidly digestible starch (up to −37 % in W-R-WF), higher slowly digestible starch (up to three times in WR) and resistant starch contents (from five to six times in Y-R-WF, W-R-WF, W-R, Y-R) of medium-high sensorially rated bread matrices. All single and blended maize-based breads can be labelled as high-fibre breads (6 g dietary fibre (DF)/100 g food). According to health-related benefits and prebiotic dosage of resistant starch a daily intake of 100 g of single Y-R, W-R, W-R-WF and W-R-WF provides enough resistant starch to positively affect postprandial glucose and insulin levels, while 170 g covers the amount necessary to enhance health.The authors acknowledge the financial support of the Spanish Institutions Consejo Superior de Investigaciones Científicas (CSIC) and Ministerio de Economía y Competitividad (Project AGL2011-22669) for carrying out this research. The Interdepartamental Centre for Agri-Food Industrial Research (F. Balestra) and the Department of Food Science (D. Ancarani) at Alma Mater Studiorum of University of Bologna granted and funded stages performed at IATA-CSIC.Peer Reviewe

Social desirability in virtual communities

As virtual worlds and social media in general become important settings for marketing actions, we need to know what is the weight of social norms within such contexts. To what degree can a researcher expect that the answers obtained within a virtual world \u2013 ultimately a social network \u2013 reflect real opinions and are not inflated by social desirability? Does the social context of an online community induce higher social desirability? This paper investigates whether social desirability is stronger within virtual world online communities than in the real world, observing same structural relationship among measured constructs but higher social desirability tendency in the virtual world compared to the real life. Since social networks and online communities will be more often used as research and communication platforms, increased attention needs to be paid to the social desirability tendency of the community members

Collision problems treated with the Generalized Hyperspherical Sturmian method

An hyperspherical Sturmian approach recently developed for three-body break-up processes is presented. To test several of its features, the method is applied to two simplified models. Excellent agreement is found when compared with the results of an analytically solvable problem. For the Temkin-Poet model of the double ionization of He by high energy electron impact, the present method is compared with the Spherical Sturmian approach, and again excellent agreement is found. Finally, a study of the channels appearing in the break-up three-body wave function is presented.Fil: Mitnik, Dario Marcelo. 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: Gasaneo, Gustavo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ancarani, Lorenzo Ugo. Universite de Lorraine; FranciaFil: Ambrosio, Marcelo José. 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; Argentin

Risk factors and outcome among a large patient cohort with community-acquired acute hepatitis C in Italy

BACKGROUND: The epidemiology of acute hepatitis C has changed during the past decade in Western countries. Acute HCV infection has a high rate of chronicity, but it is unclear when patients with acute infection should be treated. METHODS: To evaluate current sources of hepatitis C virus (HCV) transmission in Italy and to assess the rate of and factors associated with chronic infection, we enrolled 214 consecutive patients with newly acquired hepatitis C during 1999-2004. The patients were from 12 health care centers throughout the country, and they were followed up for a mean (+/- SD) period of 14+/-15.8 months. Biochemical liver tests were performed, and HCV RNA levels were monitored. RESULTS: A total of 146 patients (68%) had symptomatic disease. The most common risk factors for acquiring hepatitis C that were reported were intravenous drug use and medical procedures. The proportion of subjects with spontaneous resolution of infection was 36%. The average timespan from disease onset to HCV RNA clearance was 71 days (range, 27-173 days). In fact, 58 (80%) of 73 patients with self-limiting hepatitis experienced HCV RNA clearance within 3 months of disease onset. Multiple logistic regression analyses showed that none of the variables considered (including asymptomatic disease) were associated with increased risk of developing chronic hepatitis C. CONCLUSIONS: These findings underscore the importance of medical procedures as risk factors in the current spread of HCV infection in Italy. Because nearly all patients with acute, self-limiting hepatitis C - both symptomatic and asymptomatic - have spontaneous viral clearance within 3 months of disease onset, it seems reasonable to start treatment after this time period ends to avoid costly and useless treatment

Conditionally Exactly Solvable Potentials and Supersymmetric Transformations

A general procedure is presented to construct conditionally solvable (CES) potentials using the techniques of supersymmetric quantum mechanics.The method is illustrated with potentials related to the harmonic oscillator problem.Besides recovering known results,new CES potentials are also obtained within the framework of this general approach.The conditions under which this method leads to CES potentials are also discussed.Comment: 10 pages,Reference adde

Generalized Sturmian Functions applied to double continuum problems

The Generalized Sturmian Functions method aims to deal with atomic physics problems. It has seen application to two and three?body problems, and its flexibility enables one to work with bound systems as well as with particles in the continuum. In the present contribution we analyze how the method expands the atomic double continuum in collision problems, using the double ionization of Helium by fast electrons as a showcase. We first test the robustness of the method in a particularly challenging situation, the zero energy case. We then present fully differential cross sections for a scattering problem which after 15 years of continued efforts has not been satisfactorily solved: the double ionization of Helium by electron impact in the fast projectile regime, as measured by the Orsay group.Fil: Ambrosio, Marcelo José. 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: Colavecchia, Flavio Dario. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; ArgentinaFil: Mitnik, Dario Marcelo. 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: Gasaneo, Gustavo. Universidad Nacional del Sur; ArgentinaFil: Ancarani, L. U.. Université de Lorraine; Franci