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Abstract The f(R, T) gravity models, for which R is the Ricci scalar and T is the trace of the energy–momentum tensor, elevate the degrees of freedom of the renowned f(R) theories, by making the Einstein field equations of the theory to also depend on T. While such a dependence can be motivated by quantum effects, the existence of imperfect or extra fluids, or even a cosmological “constant” which effectively depends on T, the formalism can truly surpass some deficiencies of f(R) gravity. As the f(R, T) function is arbitrary, several parametric models have been proposed ad hoc in the literature and posteriorly confronted with observational data. In the present article, we use gaussian process to construct an $$f(R,T)=R+f(T)$$ f ( R , T ) = R + f ( T ) model. To apply the gaussian process we use a series of measurements of the Hubble parameter. We then analytically obtain the functional form of the function. By construction, this form, which is novel in the literature, is well-adjusted to cosmological data. In addition, by extrapolating our reconstruction to redshift $$z=0$$ z = 0 , we were able to constrain the Hubble constant value to $$H_0=69.97\pm 4.13\ \hbox {km}\ \hbox {s}^{-1} \ \hbox {Mpc}^{-1}$$ H 0 = 69.97 ± 4.13 km s - 1 Mpc - 1 with $$5\%$$ 5 % precision. Lastly, we encourage the application of the functional form herewith obtained to other current problems of observational cosmology and astrophysics, such as the rotation curves of galaxies.

The study of spinning systems plays a question of interest in several research branches in physics. It allows the understanding of simple classical mechanical systems but also provides us with tools to investigate a wide range of phenomena, from condensed matter physics to gravitation and cosmology. In this contribution, we review some remarkable theoretical aspects involving the description of spinning quantum systems. We explore the nonrelativistic and relativistic domains and their respective applications in fields such as graphene physics and topological defects in gravitation.

Introducción: El personal de enfermería se enfrenta cotidianamente a diferentes eventos asociados al estrés, factores psicosociales y otros mecanismos que afectan su salud mental. Objetivo: Evaluar la correlación entre la demanda psicológica, el control laboral, el apoyo social, el estrés psicológico, y las dimensiones del Síndrome de Burnout (ilusión por el trabajo, desgaste psíquico, indolencia y culpa), en un modelo de trayectorias en enfermeras mexicanas. Metodología: Estudio transversal, observacional, analítico, conducido en 357 profesionales de enfermería de Morelos, México, seleccionados por conveniencia. Los datos fueron colectados empleando tres cuestionarios, la Escala de Estrés Percibido, el Cuestionario del Contenido del Trabajo y el Cuestionario para la Evaluación del Síndrome de Quemarse por el Trabajo. Los programas SPSS 19 y LISREL 8.3 fueron empleados para el procesamiento y modelaje de los datos. Resultados: En el modelo de trayectorias, se especificó como variable mediadora de los factores psicosociales y de las dimensiones del Síndrome de Quemarse por el Trabajo (SQT), al estrés psicológico. Los índices de ajuste fueron aceptables. Se encontraron altos niveles de apoyo social, control laboral e ilusión por el trabajo; grados moderados de demanda psicológica y estrés psicológico; y bajos niveles de desgaste psíquico, indolencia y culpa. Conclusión: Implicaciones para la disciplina, se propone implementar estrategias de intervención efectivas para mantener en el personal de enfermería bajos niveles de demandas psicológicas, altos niveles de control laboral, altos niveles de apoyo social, y niveles moderados de estrés, para prevenir, el SQT.

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Abstract Fibrodysplasia ossificans progressiva (FOP) is an ultrarare condition and one of the most impactful disorders associated with progressive heterotopic ossification events. It is estimated that there are 120–150 patients in Brazil; however, currently, fewer than 100 patients have been identified, and the role of a FOP advocacy group (FOP Brazil) has been instrumental for the identification and follow-up of these individuals and families. The aim of this article is to summarize the current status of FOP in Brazil and describe strategies proposed to approach this challenge in a continental size country.

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Abstract Individual leaf area (LA) is a key variable in studies of tree ecophysiology because it directly influences light interception, photosynthesis and evapotranspiration of adult trees and seedlings. We analyzed the leaf dimensions (length – L and width – W) of seedlings and adults of seven Neotropical rainforest tree species (Brosimum rubescens, Manilkara maxima, Pouteria caimito, Pouteria torta, Psidium cattleyanum, Symphonia globulifera and Tabebuia stenocalyx) with the objective to test the feasibility of single regression models to estimate LA of both adults and seedlings. In southern Bahia, Brazil, a first set of data was collected between March and October 2012. From the seven species analyzed, only two (P. cattleyanum and T. stenocalyx) had very similar relationships between LW and LA in both ontogenetic stages. For these two species, a second set of data was collected in August 2014, in order to validate the single models encompassing adult and seedlings. Our results show the possibility of development of models for predicting individual leaf area encompassing different ontogenetic stages for tropical tree species. The development of these models was more dependent on the species than the differences in leaf size between seedlings and adults.