The Use of Multivariate Analysis in Tropical Grass and Legume Seed Production in Cuban Regions

Seed production is an important activity in developing countries where pastures are the main source for animal feeding (Febles et al. 2003). Another outstanding aspect is the mathematical analysis used when a large number of species, varieties and ecotypes are used in the same study. The objective of this paper was to examine the use of multivariate analysis in studies on the effects of edaphoclimatic factors on seed production from tropical grasses and legumes

Nivel de actividad deportiva en el tiempo libre desde las etapas de cambio y motivación en estudiantes de Costa Rica, México y España

El objetivo del presente trabajo fue analizar como las etapas de cambio y la motivación pueden predecir el nivel de actividad deportiva en el tiempo libre de alumnado de educación secundaria en educación física. La muestra fue de 2168 estudiantes, seleccionados aleatoriamente, de Costa Rica (423), México (408) y España (1337), siendo 1052 chicos, 1037 chicas y 79 no reejaron el sexo, con edades de entre 11 y 16 años (M=12.49; DT=.81). Se utilizó un cuestionario con escalas validadas para preguntar al alumnado sobre su actividad físico-deportiva en el tiempo libre, etapas de cambio y para medir la motivación de éstos. Se realizaron análisis de consistencia interna, de correlaciones y factoriales conrmatorios con SPSS 17.0. Los resultados muestran que los alumnos más activos son los de Costa Rica, situándose la mayoría de ellos en la etapa de cambio activa pero con índices de práctica y de motivación intrínseca bajos, seguidos de los españoles, pero con niveles altos de autodeterminación. México es el país más inactivo, con mayores niveles de amotivación, y los escolares que practican lo hacen con índice de práctica bajo y se encuentran en etapas inactivas. Se concluyó que en los tres países las diferencias signicativas encontradas en la motivación de los estudiantes indican la necesidad de seguir estrategias motivacionales adecuadas para aumentar la actividad física en el tiempo libre, consiguiendo así mayor número de adolescentes en etapas activas.

The impact of a web-based lifestyle educational program (‘Living Better’) Reintervention on hypertensive overweight or obese patients

‘Living Better’, a self-administered web-based intervention, designed to facilitate lifestyle changes, has already shown positive short-and medium-term health benefits in patients with an obesity–hypertension phenotype. The objectives of this study were: (1) to examine the long-term (3-year) evolution of a group of hypertensive overweight or obese patients who had already followed the ‘Living Better’ program; (2) to analyze the effects of completing this program a second time (reintervention) during the COVID-19 pandemic. A quasi-experimental design was used. We recruited 29 individuals from the 105 who had participated in our first study. We assessed and compared their systolic and diastolic blood pressure (SBP and DBP), body mass index (BMI), eating behavior, and physical activity (PA) level (reported as METs-min/week), at Time 0 (first intervention follow-up), Time 1 (before the reintervention), and Time 2 (post-reintervention). Our results showed significant improvements between Time 1 and Time 2 in SBP (-4.7 (-8.7 to -0.7); p = 0.017), DBP (-3.5 (-6.2 to -0.8); p = 0.009), BMI (-0.7 (-1.0 to -0.4); p 0.24). Implementation of the ‘Living Better’ program maintained positive long-term (3-year) health benefits in patients with an obesity–hypertension phenotype. Moreover, a reintervention with this program during the COVID-19 pandemic produced significant improvements in blood pressure, BMI, eating behavior, and PA. © 2022 by the authors. Licensee MDPI, Basel, Switzerland

Critical parameters of the three-dimensional Ising spin glass

We report a high-precision finite-size scaling study of the critical behavior of the three-dimensional Ising Edwards-Anderson model (the Ising spin glass). We have thermalized lattices up to L=40 using the Janus dedicated computer. Our analysis takes into account leading-order corrections to scaling. We obtain Tc = 1.1019(29) for the critical temperature, \nu = 2.562(42) for the thermal exponent, \eta = -0.3900(36) for the anomalous dimension and \omega = 1.12(10) for the exponent of the leading corrections to scaling. Standard (hyper)scaling relations yield \alpha = -5.69(13), \beta = 0.782(10) and \gamma = 6.13(11). We also compute several universal quantities at Tc.Comment: 9 pages, 5 figure

Critical Behavior of Three-Dimensional Disordered Potts Models with Many States

We study the 3D Disordered Potts Model with p=5 and p=6. Our numerical simulations (that severely slow down for increasing p) detect a very clear spin glass phase transition. We evaluate the critical exponents and the critical value of the temperature, and we use known results at lower $p$ values to discuss how they evolve for increasing p. We do not find any sign of the presence of a transition to a ferromagnetic regime.Comment: 9 pages and 9 Postscript figures. Final version published in J. Stat. Mec

Janus II: a new generation application-driven computer for spin-system simulations

This paper describes the architecture, the development and the implementation of Janus II, a new generation application-driven number cruncher optimized for Monte Carlo simulations of spin systems (mainly spin glasses). This domain of computational physics is a recognized grand challenge of high-performance computing: the resources necessary to study in detail theoretical models that can make contact with experimental data are by far beyond those available using commodity computer systems. On the other hand, several specific features of the associated algorithms suggest that unconventional computer architectures, which can be implemented with available electronics technologies, may lead to order of magnitude increases in performance, reducing to acceptable values on human scales the time needed to carry out simulation campaigns that would take centuries on commercially available machines. Janus II is one such machine, recently developed and commissioned, that builds upon and improves on the successful JANUS machine, which has been used for physics since 2008 and is still in operation today. This paper describes in detail the motivations behind the project, the computational requirements, the architecture and the implementation of this new machine and compares its expected performances with those of currently available commercial systems.Comment: 28 pages, 6 figure