Band structure effects in Auger neutralization of He ions at metal surfaces

A comparative study of Auger neutralization (AN) of He ions at noble metal surfaces is presented in order to reveal how the electronic structure of the sample influences this charge exchange process. Comparison of calculated ion fractions to experimental data obtained in low energy ion scattering (LEIS) shows that good agreement is achieved only if the relevant aspects of the He-metal interaction are properly taken into consideration. For instance AN depends sensitively on the distance-dependent position of the projectile level, which varies significantly when considering different target materialsSupport by the Austrian Science Fund FWF (projects P20831 and P19595) and the Spanish Ministerio de Ciencia e Innovación (project FIS2008-04209) is gratefully acknowledge

Factores socioeducativos asociados a la percepción de la investigación entre estudiantes de estomatología en una universidad cubana.

Introduction: Conducting research at the undergraduate level is essential to prepare future professionals for the process of properly channeling their scientific interest and provision of care. However, the factors influencing the degree of participation of students in research are unknown. Aim: To determine the socio-educational factors associated with the perception of research among stomatology students in a Cuban university. Materials and Methods: Cross-sectional analytical study conducted on 166 stomatology students. Participants received an anonymous, validated and self-administered questionnaire designed to collect information on the perception of scientific research within the educational spectrum, which included elements related to writing, participation, scientific publication and the interest of pursuing a career in research. Using associative statistics, those who had an overall positive perception of research were considered interested and were assessed according to socio-educational variables. Results: Students showed a positive perception of scientific research; however, when asked if they wanted to pursue a career in research, only 61.4% responded affirmatively. This positive perception increases with the progression of academic years (p<0.04), is higher in males (p=0.030) and in students who perform assistantships in core courses (p=0.001). Conclusions: There is a positive perception of scientific research, which tends to be intensified by academic progression and other factors. This must be considered by educational institutions in order to generate strategies as a response.Introducción: La investigación en el pregrado constituye una forma importante de preparar a los futuros profesionales para encauzar sus inquietudes científicas y la labor asistencial. Sin embargo, se desconocen los factores que influyen en la participación de los estudiantes en investigación. Objetivo: Determinar los factores socioeducativos asociados a la percepción de la investigación en estudiantes de estomatología de una universidad cubana. Materiales y Métodos: Estudio transversal-analítico, realizado en 166 estudiantes de estomatología. Los participantes recibieron un cuestionario anónimo, validado y autoadministrado para recoger información sobre la percepción de la investigación científica, que incluyó elementos relacionados con la redacción, la participación, la publicación científica y el interés de hacer una carrera de investigación en el futuro. A los que tuvieron una mejor percepción de la investigación se les consideró como interesados, y se les cruzó según sus variables socioeducativas, con estadísticos de asociación. Resultados: Los estudiantes mostraron una percepción positiva de la investigación científica; sin embargo, cuando se les preguntó si querían hacer una carrera de investigación en el futuro solo el 61,4% respondió afirmativamente. La percepción aumenta según progresan los años académicos (p<0,04), es mayor en los hombres (p=0,030) y en los estudiantes que realizan ayudantía en las cátedras de la carrera (p=0,001). Conclusiones: Existe una percepción positiva con respecto a la investigación científica, la cual aumentan conforme lo hacen los años académicos y otros factores; esto debe tomarse en cuenta para generar estrategias por parte de las instituciones educativas

VIH/SIDA: COMPORTAMIENTO EPIDEMIOLÓGICO DE LA TRANSMISIÓN VERTICAL EN EL CONTEXTO GENERAL DE LA INFECCIÓN EN CHILE

Antecedentes: En embarazadas seropositivas sin profilaxis antirretroviral la transmisión vertical (TV) del VIH es de 30%, cifra que disminuye bajo al 2% con un manejo integral de prevención. Objetivo: Conocer el comportamiento epidemiológico de la TV en Chile desde la creación del programa nacional de prevención. Método: Datos aportados por el Departamento de Epidemiología del MINSAL y CONASIDA (1984-2006). Estudió de situación VIH/SIDA por año, regiones, grupo etario y sexo, con especial énfasis en TV. Resultados: Se notificaron 9.317 casos de VIH y 7.886 casos de SIDA (1984-2006), prevalencia en aumento hasta el 2003 con tendencia descendente posteriormente. La razón actual de VIH entre hombres y mujeres es de 4:1, con clara tendencia al aumento de notificación en mujeres. La principal vía de exposición sigue siendo la vía sexual (93,4%). El grupo más afectado está entre los 20-39 años (73,1% para VIH y 63,1% para SIDA), cabe destacar que entre 0-9 años se encuentra el 1,1% de los afectados por VIH y el 1,4% por SIDA, todos infectados por TV. Conclusiones: La transmisión vertical de VIH en Chile es responsable de un bajo porcentaje de las personas notificadas de VIH/SIDA, pero es la causa de la totalidad de los niños afectados por la infección en nuestro país. Se observa una importante reducción de la TV, llegando a niveles muy cercanos a los objetivos ministeriales

Three decades of continuous ocean observations in North Atlantic Spanish waters: The RADIALES time series project, context, achievements and challenges

Ship-based time-series observations provide crucial data for understanding marine ecosystems, improving decision making in ocean and coastal management. However, only a few time series survive for more than a decade. RADIALES is one of the longest multidisciplinary programs in operation in the northern and northwestern coast of Spain. In the last 30 years, this program collected monthly data on physical, chemical and plankton observations in an array of five sections of stations representative of upwelling and stratified dynamics. Here, the main achievements, including key contributions to ecosystem conservation policies, are summarized. The development of this program, in line with similar initiatives in other countries, included phases focused on the study of seasonality, on comparative analysis, and lately on the analysis of decadal variability and regime shifts. Furthermore, in recent years there was a substantial improvement in the identification of plankton species by genomics. Among the main findings of RADIALES are the quantification of ocean warming at subsurface layers, the determination of climatologies in thermohaline, biogeochemical and biological variables, the inventory of plankton species (from bacteria to zooplankton) and the identification of regionally coherent regime shifts. Baselines defined by RADIALES series were instrumental for the assessment of environmental impacts (e.g. oil spills) and for the support of environmental policies (e.g. Marine Strategy Framework Directive). By contributing to international databases, data from programs as RADIALES combined with new instrumental observations will help to develop a more coherent and comprehensive understanding of the ocean ecosystems, enhancing our ability to detect and forecast risks.IEO, GAIN (Xunta de Galicia)Versión del editor3,26

Las alternativas ciudadanas para otros mundos posibles: pensamiento y experiencias

El documento está conformado por tres partes: la primera define algunos conceptos y expone ciertas teorías sobre el desarrollo y las alternativas (los artículos que componen este apartado son: "Diversidad y dinamismo de las alternativas ciudadanas", "¿Desarrollo alternativo o alternativas al desarrollo? repensando el concepto desde el territorio y el sur global"); la segunda, hace referencia a la construcción de algunas experiencias concretas relacionadas con las alternativas ciudadanas ("La gestión compleja del agua", "La alternativa educativa intercultural wixárika"; "Los procesos sociales en la construcción de alternativas a conflictos ambientales en la cuenca alta del río Santiago"). La tercera parte consiste en una propuesta de investigación sobre las alternativas ciudadanas ("Las alternativas ciudadanas: una propuesta de análisis").ITESO, A.C

Factors associated with interest in scientific research in dental students of six Cuban universities

"Introduction: To determine the factors associated with interest in scientific research in dental students of six Cuban universities. Methods: This is a multicenter cross-sectional analytical study. Interest in scientific research was the dependent variable, and it was assessed through a questionnaire proved to be reliable (Cronbach’s α= 0.88). We obtained adjusted prevalence ratios (aPR), 95% confidence intervals (95% CI), and p values through generalized linear models. Results: A total of 587 students were part of the research, and 57.9% manifested interest in scientific research. However, when they were asked if they wanted to pursue a research career in the future, only 45.1% responded affirmatively. We found, through multivariate analysis, that there was more interest in scientific research among those who were student assistants (aPR: 2.42; 95% CI: 1.41–4.16; p = 0.001), those who had previous studies (aPR: 1.35; 95% CI: 1.02–1.79; p = 0.034), and those who had received awards in scientific events (aPR: 1.74; 95% CI: 1.26–2.41; p = 0.001). In contrast, there was less interest among those who were at the clinical stage of their career (aPR: 0.66; 95% CI: 0.49–0.89; p = 0.006), adjusted for seven variables. Conclusions: There exists interest in scientific research and we found some factors associated with this. This has to be taken into account in order for educational institutions to generate strategies.

Factors associated with interest in scientific research in dental students of six Cuban universities

"Introduction: To determine the factors associated with interest in scientific research in dental students of six Cuban universities. Methods: This is a multicenter cross-sectional analytical study. Interest in scientific research was the dependent variable, and it was assessed through a questionnaire proved to be reliable (Cronbach’s α= 0.88). We obtained adjusted prevalence ratios (aPR), 95% confidence intervals (95% CI), and p values through generalized linear models. Results: A total of 587 students were part of the research, and 57.9% manifested interest in scientific research. However, when they were asked if they wanted to pursue a research career in the future, only 45.1% responded affirmatively. We found, through multivariate analysis, that there was more interest in scientific research among those who were student assistants (aPR: 2.42; 95% CI: 1.41–4.16; p = 0.001), those who had previous studies (aPR: 1.35; 95% CI: 1.02–1.79; p = 0.034), and those who had received awards in scientific events (aPR: 1.74; 95% CI: 1.26–2.41; p = 0.001). In contrast, there was less interest among those who were at the clinical stage of their career (aPR: 0.66; 95% CI: 0.49–0.89; p = 0.006), adjusted for seven variables. Conclusions: There exists interest in scientific research and we found some factors associated with this. This has to be taken into account in order for educational institutions to generate strategies.

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO