Maximizing the hyperpolarizability of one-dimensional systems

Previous studies have used numerical methods to optimize the hyperpolarizability of a one-dimensional quantum system. These studies were used to suggest properties of one-dimensional organic molecules, such as the degree of modulation of conjugation, that could potentially be adjusted to improve the nonlinear-optical response. However, there were no conditions set on the optimized potential energy function to ensure that the resulting energies were consistent with what is observed in real molecules. Furthermore, the system was placed into a one-dimensional box with infinite walls, forcing the wavefunctions to vanish at the ends of the molecule. In the present work, the walls are separated by a distance much larger than the molecule's length; and, the variations of the potential energy function are restricted to levels that are more typical of a real molecule. In addition to being a more physically-reasonable model, our present approach better approximates the bound states and approximates the continuum states - which are usually ignored. We find that the same universal properties continue to be important for optimizing the nonlinear-optical response, though the details of the wavefunctions differ from previous result.Comment: 10 pages, 5 figure

Use of a new ocular insert versus conventional mydriasis in cataract surgery

Background. To compare the efficacy and safety of a new ocular insert versus conventional mydriasis in cataract surgery. Methods. We selected 70 patients undergoing cataract surgery. Thirty five patients (Group 1) received instillation of mydriatic drops (tropicamide 1%, phenylephrine 10%, and cyclopentolate 1%) prior to surgery, and 35 patients (Group 2) had a Mydriasert insert (Théa Pharma) (0.28¿mg of tropicamide and 5.4¿mg of phenylephrine hydrochloride) placed in the inferior fornix. Pupil size before and after surgery, blood pressure, and heart rate were measured. Results. Before surgery, pupil diameter was ¿mm in Group 1 and in Group 2 ( ). Twenty four hours after surgery, pupil diameter was ¿mm in Group 1 and in Group 2 ( ). There were no statistically significant differences in blood pressure or heart rate between groups. Conclusions. The effect of the Mydriasert insert was similar to conventional mydriatic agents. Pupil size was restored to normal faster when using the Mydriasert insert compared with conventional mydriatic agents for pupil dilation

Web based hybrid volumetric visualisation of urban GIS data: Integration of 4D Temperature and Wind Fields with LoD-2 CityGML models

City models visualisation, buildings, structures and volumetric information, is an important task in Computer Graphics and Urban Planning -- The different formats and data sources involved in the visualisation make the development of applications a big challenge -- We present a homogeneous web visualisation framework using X3DOM and MEDX3DOM for the visualisation of these urban objects -- We present an integration of different declarative data sources, enabling the utilization of advanced visualisation algorithms to render the models -- It has been tested with a city model composed of buildings from the Madrid University Campus, some volumetric datasets coming from Air Quality Models and 2D layers wind datasets -- Results show that the visualisation of all the urban models can be performed in real time on the Web -- An HTML5 web interface is presented to the users, enabling real time modifications of visualisation parameter

Adductor squeeze test and groin injuries in elite football players: A prospective study

during the competitive season of professional football teams. Design: Prospective Cohort study. Setting: Controlled laboratory environment. Participants: Seventy-one players volunteered to participate. Main outcome measures: In the pre-season, maximal hip adductor strength was measured by means of the isometric adductor squeeze test. Hip adductor strength, normalized by body mass, was compared between players who suffered a groin injury (n ¼ 18) vs uninjured players (n ¼ 53). Risk ratios (RR) were used to evaluate the likelihood of players to suffer this type of injury. Results: Most of the reported groin injuries occurred during competitive matches (5.5 per 1000 match hours). Maximal isometric hip adductor strength was lower in the groin-injured group compared with their uninjured counterparts (429.8 ± 100 vs 564 ± 58.7 N, d¼ 1.58 and 5.40 ± 1.27 vs 7.71 ± 0.89 N/kg, d¼ 1.88, respectively). Results revealed that values of maximal isometric adductor strength lower than 465.33 N increased the probability to suffer a groin injury by 72%. Furthermore, values of force relative to body mass lower than 6.971 N/kg increased the probability to suffer a groin injury by 83%. Conclusion: The assessment of Hip adductor strength, in addition to other measurements, might help practitioners to determine the probability of suffering an overuse groin injuries in elite football players.info:eu-repo/semantics/publishedVersio

Nuclear astrophysics with radioactive ions at FAIR

The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process beta-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes

Madurez de la deuda corporativa como variable de tiempo: evidencia de las empresas públicas de México

Maturity of Corporate Debt as a Time Variable: Evidence of Public Firms from MexicoThis research aims to determine the factors of debt maturity for Mexican companies listed on the BMV, using an alternative method to define the dependent variable. Maturity is defined as "time to contract expiration" considering the weighted average of the expiration time, which contributes to the originality of this work. Panel data models and the Heckman selection model are used, since working with an unbalanced longitudinal panel can present sample selection problems due to atrition. The results suggest that the attrition bias is significant, and that the average maturity of the debt is determined by firm characteristics such as size and leverage, among others, and the interest rate of the Mexican market. As a limitation and due to the omissions of data reported by the information sources used for the analysis, a short and unbalanced panel is used. It is concluded that, by using this maturity alternative measurement method, better results are obtained to analyze the maturity of the debt, compared to the traditional metrics in the literature.El objetivo de esta investigación es identificar los determinantes de la madurez de la deuda para las empresas mexicanas que cotizan en la BMV, usando una definición alternativa de esta variable dependiente. En particular, se define la madurez como “tiempo para expiración del contrato” considerando el promedio ponderado del tiempo a vencimiento, contribución original del presente trabajo. Se utilizan modelos de datos panel y de selección de Heckman, pues el uso de datos longitudinales en un panel desbalanceado puede presentar problemas de selección en forma de atrición. Los resultados sugieren que el sesgo por atrición es significativo, y que la madurez promedio de la deuda está determinada por variables como tamaño y apalancamiento, entre otras característias de las empresas, así como la tasa de interés del mercado. Como principal limitación, se tienen las omisiones de datos de las fuentes de información utilizadas generando un panel corto y desbalanceado. Se concluye que al usar este método de medición de madurez se obtienen mejores resultados para analizar el plazo de vencimiento de la deuda, comparado con las métricas tradicionales en la literatura

Evaluación genética: un paso inicial para mejorar la producción bovina

El 65% de la población bovina mundial se encuentra en los países tropicales y solo un 35% en los países desarrollados. pero estos últimos producen el 10% más de leche y el 4% más de carne. Uno de los factores que ha incidido en la eficiencia de la producción de carne y leche de los países desarrollados ha sido la utilización de los registros y el análisis de la información acerca de las características productivas y reproductivas de los hatos. tomada en la empresa ganadera. Ello ha permitido. a su vez. el diseño y la puesta en marcha de programas de mejoramiento genético. con el objetivo de seleccionar para la producción y la cría los mejores animales bajo las condiciones de cada país en particular.Ganadería bovin

Aclimatización ex vitro de Kalanchoe blossfeldiana Poelln.

Kalanchoe blossfeldiana Poelln. is an ornamental specie used as a plant for pots and garden. Although are found studies on its propagation by biotechnological methods, the conditions to guarantee high survival rates in the acclimatization stage of in vitro plants have not been described. The aim of this work was to evaluate the development of K. blossfeldianain vitro plants during the acclimatization stage. Rooted plants were used in a culture medium without growth regulators. For planting, two mixtures of substrate were used in proportion 80:20, earthworm humus:zeolite and earthworm humus: sand. During the acclimatization the percentage of survival was calculated at 7, 15 and 30 days, and the plants height was measured at 30 days. In the rooting stage an average of 9.8 roots and a 0.9 cm height per plant was obtained. The survival in the acclimatization was 97.5% for both substrates, and there were no significant differences for the variable height of the plant. According to the results, with the substrates used for the acclimatization of K. blossfeldiana in vitro plants, high percentages of survival can be obtained under the conditions studied in the present work.Keywords:Crassulaceae, earthworm humus, substrae, zeoliteKalanchoe blossfeldiana Poelln. es una especie ornamental usada como planta para macetas y jardín. Aunque se encuentran estudios sobre su propagación por métodos biotecnológicos, no han sido descritas las condicionespara garantizar altos porcentajes de supervivencia en la fase de aclimatización de las plantas in vitro. El objetivo del presente trabajo fue evaluar el desarrollo de plantas in vitro de K. blossfeldiana durante la fase de aclimatización. Se emplearon plantas enraizadas en un medio de cultivo sin reguladores de crecimiento. Para la plantación se usaron dos mezclas de sustrato en proporción 80:20, humus de lombriz:zeolita y humus de lombriz:arena. Durante la aclimatización se calculó el porcentaje de supervivencia a los 7, 15 y 30 días, y se midió la altura de las plantas a los 30 días. En el enraizamiento se obtuvo un promedio de 9.8 raíces y una altura de 0.9 cm por planta. La supervivencia en la aclimatización fue 97.5% para ambos sustratos, y no hubo diferencias significativas para la variable altura de la planta. De acuerdo con los resultados, con los sustratos empleados para la aclimatización de plantas in vitro de K. blossfeldiana,pueden ser obtenidos altos porcentajes de supervivencia bajo las condiciones estudiadas en el presente trabajo.Palabras clave:Crassulaceae, humus de lombriz, sustrato, zeolit

Heat Treatment of Aluminium Foam Precursors: Effects on Foam Expansion and Final Cellular Structure

Aluminium foams produced by the powder metallurgical route present an initial –anisotropic– semisolid expansion that has a detrimental effect on the foamability and on the subsequent quality of the final cellular structure. The present work proposes a method oriented to modify the precursors’ microstructure and overcome this problem. It is based on the use of heat treatments below the solidus temperature, and has been tested in AlSi10 (0.8 wt.%TiH2) commercial precursors from Alulight Company (Austria). The experimental results obtained have demonstrated that the thermal treatment induces notable changes in the microstructure of the precursor material. Then, these changes produce a reduced and smoother semisolid expansion and improve the quality of the final cellular structure, in terms of higher pore circularity and less amount of defects.Spanish Ministry of Science and Innovation and FEDER funds; Junta of Castile and Leo

Diseño de una maqueta para medidas de la atenuación del ruido de tráfico rodado mediante pantallas acústicas

Hoy en día es muy importante saber cómo diseñar una pantalla de ruido de carreteras que se adapte a su entorno y tenga las funciones acústicas y estructurales previstas. En este trabajo se diseña un sistema experimental para realizar medidas de la atenuación del ruido de tráfico rodado. Una maqueta realizada en madera de ocumen nos pemite cambiar la sección transversal de la coronación de la pantalla. Para estudiar la validez del diseño se ha medido a diferentes alturas, con diferentes secciones y a distinas frecuencias en el rango entre 63 y 5000 H