Data sciences and teaching methods—learning

Data Science (DS) is an interdisciplinary field responsible for extracting knowledge from the data. This discipline is particularly complex in the face of Big Data: large volumes of data make it difficult to store, process and analyze with standard computer science technologies. The new revolution in Data Science is already changing the way we do business, healthcare, politics, education and innovation. This article describes three different teaching and learning models for Data Science, inspired by the experiential learning paradigm

Phylogenetic studies of newly isolated freshwater Magnetospirilla using cbb and mam genes

The phylogeny and general relatedness of prokaryotes is determined by comparisons of the sequences of rRNA genes, most commonly the 16S rRNA gene. Comparisons between other gene sequences have been used for this purpose and some have supported conclusions from 16S rRNA genes while others have not. In this study, 13 new magnetospirilla were phylogenetically characterized using the sequences of the 16S rRNA gene as well as the genes for forms I and II ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) (cbbL and cbbM, respectively) and for two magnetosome membrane proteins unique to magnetotactic bacteria, mamJ and mamK. Polymerase chain reaction (PCR) with degenerate primers designed for the specific genes under study was used to amplify a large portion of the genes. PCR products were cloned and sequenced and used for the construction of phylogenetic trees. Based on 16S rRNA gene sequences, the magnetospirilla phylogenetically span, more as a continuum rather than as clearly delineated groups, over two genera based on the current accepted sequence divergence between organisms for genera (\u3e5%). While almost all strains appear to fit into the genus Magnetospirillum, strain LM-1 appears to represent a new genus. Phylogeny of these strains based on cbbM sequences was reasonably consistent with that from 16S rRNA genes. The cbbL gene was not a good choice for this study as most strains did not possess this gene. Relatedness and phylogeny of the strains based on mamJ and mamK sequences was more complex. Although our data set is not complete, some specific strains shown to be closely related by 16S rRNA gene sequence, also appeared to be closely related based on one or both of the mam gene sequences (e.g., strains UT-1, LM-2 and M. gryphiswaldense strain MSR-1). Other strains did not show this type of relationship. Because of these somewhat inconsistent results, those from mam gene sequences might reflect evolution of the magnetosome gene island (MAI) in magnetospirilla rather than relatedness between strains

Estudio funcional del cortisol y ACTH plasmáticos en perros : respuesta ante el estímulo con hormona liberadora de corticotrofina (CRF) en situación de anestesia

La acción de los agentes anestésicos sobre la ACTH y el cortisol es variable. Nos interesó ver el comportamiento del eje hipotálarno-hipófisoadrenal en situación de anestesia. Igualmente se estudia la capacidad de respuesta de este eje cuando, estando bajo el efecto de la anestesia, se somete a un estímulo fisiológico. Se observa que el pentotal sódico produce descenso del nivel de cortisol y ACTH.Aún estando el animal anestesiado, las glándulas adrenales tienen capacidad de respuesta ante estímulos fisiológicosThe action of the anaesthetic agents on ACTH and cortisol is variable. In the present paper we were interested to see the behauiour of the hypothalamus bypophysis-adrenal axis in a state of anaesthesia. In the same way we study the response capacity of this axis when, being under the effect of anaesthesia, it is submitted to a physiological stimulus. We observe sodium pentothal produces a decrease in the level of cortisol and ACTH. Even when the animal is anaesthetized, the adrenal glands have the response capacity in the presence of physiological stimuli

Determination of contents based on learning styles through artificial intelligence

The study presents the development of a platform for structuring adaptive courses based on active, reflexive, theoretical and pragmatic learning styles using artificial intelligence techniques. To this end, the following phases were followed: search, analysis and classification of information about the process of generating content for courses; analysis and coding of the software component for generating content according to learning styles; and application of tests for validation and acceptance. The main contribution of the paper is the development of a model using neural networks and its integration in an application server to determine the contents that correspond to the active, reflexive, theoretical and pragmatic learning styles

Atlas costero de temperatura y salinidad superficial en el Cantábrico

Atlas costero de la temperatura y salinidad superficial creado a partir de los datos del termosalinógrafo instalado en el B/O José Rioja, desde octubre de 2002 a diciembre de 2011 para la región del mar Cantábrico situada entre Cudillero y Santander

Place Bonaventure : process, form, and interpretation

Traces the background of architect R.T. Affleck; how he went about designing Place Bonaventure (a multi-use complex situated in downtown Montreal); and, how a diverse public has come to react to the building

Analysis of the behavior of daily maximum rainfall within the department of Atlántico, Colombia

In the Colombian Caribbean region, there are few studies that evaluated the behavior of one of the most commonly used variables in hydrological analyses: the maximum daily rainfall (Pmax-24h). In this study, multiannual Pmax-24h time series from 19 rain gauges, located within the department of Atlántico, were analyzed to (a) determine possible increasing/decreasing trends over time, (b) identify regions with homogeneous behavior of Pmax-24h, (c) assess whether the time series are better suited under either a stationary or non-stationary frequency analysis, (d) generate isohyetal maps under stationary, non-stationary, and mixed conditions, and (e) evaluate the isohyetal maps by means of the calculation of areal rainfall (Pareal) in nine watersheds. In spite of the presence of both increasing and decreasing trends, only the Puerto Giraldo rain gauge showed a significant decreasing trend. Also, three regions (east, central, and west) with similar Pmax-24h behavior were identified. According to the Akaike information criterion test, 79% of the rain gauges showed better fit under stationary conditions. Finally, statistical analysis revealed that, under stationary conditions, the errors in the calculation of Pareal were more frequent, while the magnitude of the errors was larger under non-stationary conditions, especially in the central-south region. © 2019 by the authors

Tratamiento quirúrgico de las pérdidas de sustancia cutánea en el carpo, mediante colgajos libres vascularizados en el perro

En el presente trabajo se describe la técnica de la transposición libre microquirúrgica de colgajos de piel, así como los resultados de dicha transferencia, realizada en cinco perros.At the present research the techníque of the free transposition mícrosurgícal of flaps is described, as well as the results from the performed transference in five dogs

Magnetic response of metallic nanoparticles: geometrical and weakly-relativistic effects

While the large paramagnetic response measured in certain ensembles of metallic nanoparticles has been assigned to orbital effects of conduction electrons, the spin-orbit coupling has been pointed out as a possible origin of the anomalously large diamagnetic response observed in other cases. Such a relativistic effect, arising from the inhomogeneous electrostatic potential seen by the conduction electrons, might originate from the host ionic lattice, impurities, or the self-consistent confining potential. Here we theoretically investigate the effect of the spin-orbit coupling arising from the confining potential, quantifying its contribution to the zero-field susceptibility and gauging it against the ones generated by other weakly-relativistic corrections. Two ideal geometries are considered in detail, the sphere and the half-sphere, focusing on the expected increased role of the spin-orbit coupling upon a symmetry reduction, and the application of these results to actual metallic nanoparticles is discussed. The matrix elements of the different weakly-relativistic corrections are obtained and incorporated in a perturbative treatment of the magnetic field, leading to tractable semi-analytical and semiclassical expressions for the case of the sphere, while a numerical treatment becomes necessary for the half-sphere. The correction to the zero-field susceptibility arising from the spin-orbit coupling in the sphere is quite small, and it is dominated by the weakly-relativistic kinetic energy correction, which in turn remains considerably smaller than the typical values of the nonrelativistic zero-field susceptibility. The symmetry reduction in going from the sphere to the half-sphere does not translate into a significative increase of the spin-orbit contribution to the zero-field susceptibility.Comment: 33 pages, 9 figure

Orbital magnetism in ensembles of gold nanoparticles

The last two decades have witnessed various experiments reporting very unusual magnetic properties of ensembles of gold nanoparticles surrounded by organic ligands, including ferromagnetic, paramagnetic, or (large) diamagnetic responses. These behaviors are at odds with the small diamagnetic response of macroscopic gold samples. Here we theoretically investigate the possibility that the observed unusual magnetism in capped gold nanoparticles is of orbital origin. Employing semiclassical techniques, we calculate the orbital component to the zero-field susceptibility of individual as well as ensembles of metallic nanoparticles. While the result for the orbital response of individual nanoparticles can exceed by orders of magnitude the bulk Landau susceptibility in absolute value, and can be either diamagnetic or paramagnetic depending on nanoparticle size, we show that the magnetic susceptibility of a noninteracting ensemble of nanoparticles with a smooth size distribution is always paramagnetic at low magnetic fields. In particular, we predict that the zero-field susceptibility follows a Curie-type law for small nanoparticle sizes and/or low temperatures. The calculated field-dependent magnetization of an ensemble of diluted nanoparticles is shown to be in good agreement with existing experiments that yielded a large paramagnetic response. The width of the size distribution of the nanoparticles is identified as a key element for the quantitative determination of the orbital response.Comment: 19 pages, 13 figures, published versio