Asteroseismology of evolved stars to constrain the internal transport of angular momentum. VI. Testing a parametric formulation for the azimuthal magneto-rotational instability

Asteroseismic measurements of the internal rotation rate in evolved stars pointed out to a lack of angular momentum (AM) transport in stellar evolution models. Several physical processes in addition to hydrodynamical ones were proposed as candidates for the missing mechanism. Nonetheless, no current candidate can satisfy all the constraints provided by asteroseismology. We revisit the role of a candidate process whose efficiency scales with the contrast between the rotation rate of the core and the surface which was proposed to be related to the azimuthal magneto-rotational instability (AMRI) by Spada et al. We compute stellar evolution models of low- and intermediate-mass stars with the parametric formulation of AM transport proposed by Spada et al. until the end of the core-helium burning for low- and intermediate-mass stars and compare our results to the latest asteroseismic constraints available in the post main sequence phase. Both hydrogen-shell burning stars in the red giant branch and core-helium burning stars of low- and intermediate-mass in the mass range $1 M_{\odot} \lesssim M \lesssim 2.5 M_{\odot}$ can be simultaneously reproduced by this kind of parametrisation. Given current constraints from asteroseismology, the core rotation rate of post-main sequence stars seems to be well explained by a process whose efficiency is regulated by the internal degree of differential rotation in radiative zones.Comment: Accepted for publication in Astronomy & Astrophysics. 10 pages, 10 figures, 1 appendi

On Weierstra{\ss} semigroups at one and two points and their corresponding Poincar\'e series

The aim of this paper is to introduce and investigate the Poincar\'e series associated with the Weierstra{\ss} semigroup of one and two rational points at a (not necessarily irreducible) non-singular projective algebraic curve defined over a finite field, as well as to describe their functional equations in the case of an affine complete intersection.Comment: Beginning of Section 3 and Subsection 3.1 were modifie

Angular momentum transport by magnetic fields in main sequence stars with Gamma Doradus pulsators

Context. Asteroseismic studies showed that cores of post main-sequence stars rotate slower than theoretically predicted by stellar models with purely hydrodynamical transport processes. Recent studies on main sequence stars, particularly Gamma Doradus ($\gamma$ Dor) stars, revealed their internal rotation rate for hundreds of stars, offering a counterpart on the main sequence for studies of angular momentum transport. Aims. We investigate whether such a disagreement between observed and predicted internal rotation rates is present in main sequence stars by studying angular momentum transport in $\gamma$ Dor stars. Furthermore, we test whether models of rotating stars with internal magnetic fields can reproduce their rotational properties. Methods. We compute rotating models with the Geneva stellar evolution code taking into account meridional circulation and the shear instability. We also compute models with internal magnetic fields using a general formalism for transport by the Tayler-Spruit dynamo. We then compare these models to observational constraints for $\gamma$ Dor stars that we compiled from the literature, combining so the core rotation rates, projected rotational velocities from spectroscopy, and constraints on their fundamental parameters. Results. We show that combining the different observational constraints available for $\gamma$ Dor stars enable to clearly distinguish the different scenarios for internal angular momentum transport. Stellar models with purely hydrodynamical processes are in disagreement with the data whereas models with internal magnetic fields can reproduce both core and surface constraints simultaneously. Conclusions. Similarly to results obtained for subgiant and red giant stars, angular momentum transport in radiative regions of $\gamma$ Dor stars is highly efficient, in good agreement with predictions of models with internal magnetic fields.Comment: Accepted for publication in Astronomy & Astrophysics. 16 pages, 17 figures, 1 appendi

Prevalence and associated factors to suicide attempts in low-income adolescents from the Caribbean region of Colombia

Objectives to establish the prevalence and associated factors to suicide attempts (SA) in low-income adolescents from the Caribbean region of Colombia Methods A cross sectional study was conducted. Adolescents between 10-24 years of age residents in 21 municipalities in the Caribbean region of Colombia were randomly selected from the population affiliated to a subsidized-regime insurance company between 2014-2018. A previously constructed questionnaire was used to obtain information regarding sociodemographic variables and potential risk factors. A self-reported antecedent of suicide attempt was defined as a case. Bivariate and multivariate logistic regression models were used to establish associated factors. Absolute and relative frequencies were reported. Relative frequencies were compared with the Chi2 test and continuous variables were compared with the t-test. A p value <0.050 was considered significan

Metodología BIM en el grado de edificación: modelo de taller en la asignatura Expresión Gráfica de Tecnologías

The concept of BIM implies a radical change in the way of facing the architectural design and the life cycle process of the projects and the buildings. It is an efficient and open system of communication and cooperation between the different operators involved in the construction process and, therefore, it becomes in a suitable tool for its implementation in the Technical Schools of Engineering and Architecture. This paper defends the recognition of the BIM methodology as a collaborative and coordinated instrument for its application in the university teaching in degrees of this field of knowledge, so that the flow of interdisciplinary information is efficient. The experience of the implementation of this methodology in the Degree in Building is described. It is based on a workshop-integrator model in the subject called Graphic Expression of Technologies. Subsequently, educational enquiries derived from the innovation developed are collected, showing its benefits for the student body as regards learning, and also the limitations found. In conclusion, the outcomes obtained lead to continue supporting this technological integration. Finally, a series of recommendations for its improvement are provided, concerning the way to guide the students throughout the experience, and also related to the teaching organisation through the curriculum

Effects of different feeding frequencies on growth, feed utilisation, digestive enzyme activities and plasma biochemistry of gilthead sea bream (Sparus aurata) fed with different fishmeal and fish oil dietary levels

In the context of Mediterranean aquaculture little attention has been paid to the manipulation of feeding frequency at the on-growing phase. The effects of different feeding frequencies: one meal per day, two meals per day, three meals per day on growth, digestive enzyme activity, feed digestibility and plasma biochemistry were studied in gilthead sea bream (Sparus aurata, L. 1758) fed with high and low fishmeal and fish oil levels. Isonitrogenous and isolipidic extruded diets were fed to triplicate fish groups by a fixed ration over 109 days. No significant effects of feeding frequency on overall performance, feed efficiency and feed digestibility during the on-growing of gilthead sea bream fed high or low fishmeal and fish oil dietary level were observed. Pepsin activity showed an apparent decrease in fish receiving more than one meal a day which was not compensated by an increased production of alkaline proteases particularly in fish fed on low FM. Although there were no effects on growth and feed utilisation at increasing feeding frequency, trypsin decreased significantly with an increasing number of meals only under low FMFO diet. Thus, it seemed that consecutive meals could have amplified the potential trypsin inhibitor effect of the vegetable meal-based diet adopted. Results of the plasma parameters related to nutritional and physiological conditions were not affected by feeding frequency. The higher level of plasma creatinine detected in fish fed a single daily meal with high FMFO level seems to be within physiological values in relation to the higher protein efficiency observed with this diet. According to the results, gilthead sea bream seems able to maximise feed utilisation regardless of the number of meals, and this could be a useful indicator for planning feeding activity at farm level to optimise growth of fish and costs of feeding procedures

Liquidity and the multiscaling properties of the volume traded on the stock market

We investigate the correlation properties of transaction data from the New York Stock Exchange. The trading activity f(t) of each stock displays a crossover from weaker to stronger correlations at time scales 60-390 minutes. In both regimes, the Hurst exponent H depends logarithmically on the liquidity of the stock, measured by the mean traded value per minute. All multiscaling exponents tau(q) display a similar liquidity dependence, which clearly indicates the lack of a universal form assumed by other studies. The origin of this behavior is both the long memory in the frequency and the size of consecutive transactions.Comment: 7 pages, 3 figures, submitted to Europhysics Letter

Interaction Between Dietary Lipid Level and Seasonal Temperature Changes in Gilthead Sea Bream Sparus aurata: Effects on Growth, Fat Deposition, Plasma Biochemistry, Digestive Enzyme Activity, and Gut Bacterial Community

A 121-day feeding trial was undertaken to test the effects of two dietary lipid levels (16 and 21% L16, L21) in triplicated gilthead sea bream groups (initial weight: 67.5 g) reared at two different water temperatures (high, H 23°C and low, L 17°C) in the same recirculation system but exposed to a switch in temperature after 58 days. Fish kept at H were transferred to L (HL transition, autumn shift), and the fish kept at L were exposed to H (LH transition, summer shift), while continuing to receive the same diet to apparent satiation in each group. At the end of the trial, no significant diet effect on specific growth rate (SGR), feed intake (FI), and feed conversion rate (FCR) were detected in fish exposed to HL transition compared with those exposed to LH transition, while gross lipid efficiency (GLE) and lipid efficiency ratio (LER) were higher in L16. After temperature changes, L16 displayed higher SGR, FI, GLE, and LER, while mesenteric fat index was reduced. After temperature changes, the combined effects of low lipid diet and low temperature conditions resulted in higher pepsin activity, while trypsin, chymotrypsin, and lipase activities were generally higher at high lipid content. The combined effect of diet and temperature did not alter the metabolic plasma profile, except for the observed final higher aspartate aminotransferase (AST) and alkaline phosphatase (ALP) values when combining high dietary lipid (L21) and temperature changes. Different diets showed a significantly different gut microbiome layout, only at high temperature with L16 diet resulting in a higher load of Lactobacillus. On the contrary, no dietary impact on ecosystem diversity was observed, independently from the temperature. In addition, L16 diet in the HL transition favored an increase in Weissella and Bradyrhizobium genera in the gut microbiome, while in the final condition of LH transition, L21 diet favored a significant increase in Streptococcus and Bacillus. According to the results, the utilization of 16% dietary lipid levels in gilthead sea bream should be preferred during seasonal temperature changes in order to optimize feed utilization and gut health

Modelo automatizado de tipificación de daños materiales por vicios o defectos que afecten a elementos de terminación y acabado en edificación

Users that detect defects in the termination of building elements frequently go to courts of justice claiming reparations and/or compensations. This situation generates in the intervening agents doubts and uncertainties about the responsibilities, consequences and penalties that they have to pay to compensate for that deficiencies. The object of present investigation is to propose and validate an automated model in the form of “predictive system” based on a software application “Expert System”. Using this software you can identify and classify these defects.Los usuarios que detectan defectos en edificaciones recientemente acabadas con frecuencia acuden a la vía judicial para reclamar su reparación. Ello genera en los agentes intervinientes cierta incertidumbre respecto a si serán o no condenados como responsables de dichos defectos. El objetivo de la presente investigación se centra en proponer y validar un modelo automatizado en forma de herramienta informatizada que, de manera sencilla, ayude a «tipificar de forma predictiva» los defectos más frecuentes y controvertidos a la hora de delimitar responsabilidades, es decir, los denominados «de terminación o acabado»

Implantación de metodología BIM en el Grado de Edificación. Modelo de taller-integrador en la asignatura de Expresión Gráfica de Tecnologías

Resumen: El concepto de BIM implica un cambio radical en la manera de afrontar el diseño arquitectónico y el proceso de ciclo de vida del proyecto y del edificio. Se trata de un sistema eficiente y abierto de comunicación y cooperación entre los distintos operadores del proceso constructivo y, por tanto, idóneo para su implantación en las Escuelas Técnicas de Ingeniería y Arquitectura. Esta comunicación defiende el reconocimiento de la metodología BIM como instrumento de trabajo colaborativo y coordinado para su aplicación en la docencia, a fin de que el flujo de información interdisciplinar sea eficiente. Se describe la experiencia de la implantación de esta metodología en el Grado de Edificación, a través de un modelo de taller-integrador en la asignatura de Expresión Gráfica de Tecnologías. Posteriormente, se recogen experiencias docentes derivadas de la innovación desarrollada, que llevan a seguir apostando por esta integración tecnológica, para cuya mejora se aportan finalmente una serie de recomendaciones. Abstract: The concept of BIM implies a radical change in the way of facing the architectural design and the life cycle process of the project and the building. It is an efficient and open system of communication and cooperation between the different operators within the construction process and, therefore, suitable for its implementation in the Technical Schools of Engineering and Architecture. This paper defends the recognition of the BIM methodology as a collaborative and coordinated tool for its application in teaching, so that the flow of interdisciplinary information is efficient. The experience of the implementation of this methodology in the Degree in Building is described, through a workshop-integrator model in the subject called Graphic Expression of Technologies. Subsequently, educational enquiries derived from the innovation developed are collected, which lead to continue supporting this technological integration. Finally, a series of recommendations for its improvement are provided