Introducción. Una reflexión sobre la pandemia del 2020

Una reflexión sobre la pandemia del 2020

El Calloviense de los Ibérides (dominio Ibérico, España). Síntesis bioestratigráfica

More than 60 Callovian geological profiles in the Iberides (between Burgos and Alicante) have been studied. The Ricla (Zaragoza) Callovian section as reference biostratigraphic outline has been established, documenting almost all Callovian Mesogean Zones and Subzones and many biohorizons. The others profiles in relation with the elected as reference are briefly described, standing out the scarce thickness and Upper Callovian and frequently Middle Callovian absence.Se han estudiado más de 60 perfiles geológicos de edad Calloviense en los Ibérides (entre Burgos y Alicante). El Calloviense de Ricla (Zaragoza) se toma como esquema bioestratigráfico de referencia, documentándose casi todas las zonas y subzonas y muchos de los biohorizontes del Calloviense de la Mesogea. Los demás perfiles se describen sumariamente en relación al elegido como referencia, destacando su escasa potencia y la falta de Calloviense superior y frecuentemente de Calloviense medio

Skill Levels on Visualization and Spatial Reasoning in Pre-service Primary Teachers

We apply theoretical tools from the onto-semiotic approach to present skill levels on tasks requiring visualization and spatial reasoning. These scales are derived from the analysis of visualization and spatial reasoning skills involved in solving a questionnaire supplied to 400 pre-service primary teachers. In order to set skill levels, we describe different types of cognitive configurations considering the network of mathematical objects involved in solving the items. The results show that there may be several configurations at each level and the levels depend on both certain conditions of the task and the visualization skills required. In most cases, the ratio of students expressing high level is significantly below than those of exhibiting low level. The analysis manifests that students put into play variety and quantity of visual objects and processes; however, most did not reach the solution successfully. This leads to the need for specific training actions.This work was funded by the Spanish FEDER/ Ministry of Science, Innovation and Universities – Research Agency / project EDU2017_84979-R, and the European Erasmus + program (2019-1-CZ01-KA201-061377)

Mathematical learning for children through project work

El quehacer diario de las maestras y maestros de Educación Infantil determina en buena medida las acciones matemáticas que su alumnado desarrolla en el aula, y que después traslada a contextos y situaciones cotidianos de su contorno. La forma de enseñar y programar experiencias y situaciones ricas en procesos matemáticos por parte de los docentes cobra por tanto importancia desde las primeras etapas educativas. Se trata de que las matemáticas supongan para el alumnado una herramienta útil y funcional, que permita la inclusión social, y no únicamente la segregación de los estudiantes por sus resultados. El trabajo por proyectos permite a priori crear situaciones significativas, en las que a través de la acción se abstraen y comprenden los nuevos aprendizajes. En este trabajo se presenta un estudio del análisis e implantación de los proyectos de trabajo en un aula de educación infantil, desde su programación hasta su evaluación, así como su correlación con las capacidades matemáticas del alumnado.The work of Early Childhood Education teachers determines to a large extent the mathematical actions which their students develop in the classroom, and which later they transfer to daily contexts. Therefore, it is important that teachers program and develop rich mathematical experiences from the first levels. It is about made mathematics a useful and functional tool for students allowing social inclusion, but not the segregation of students by results. Project-based learning allows a priori significant situations in which the new learning are abstracted and understood through the action. This paper presents a study of the analysis and implementation of work projects in a classroom for early childhood education, from its programming to its evaluation, as well as its correlation with the mathematical abilities of the students

Improvement in the molecular diagnosis of Machado-Joseph disease

Abstract BACKGROUND: Direct detection of the gene mutation allows for the confirmation of the clinical diagnosis of Machado-Joseph disease (MJD), the most frequent cause of autosomal dominant spinocerebellar ataxia worldwide. OBJECTIVE: To address the main difficulties in our national MJD predictive testing program. The first was the emergence of intermediate alleles, for which it is not yet possible to determine whether they will cause disease. The second was the issue of homoallelism, ie, homozygosity for 2 normal alleles with exactly the same (CAG)(n) length, which occurs in about 10% of all test results. METHODS: A large pedigree with 1 affected patient carrying a 71 and a 51 CAG repeat and 2 asymptomatic relatives carrying the 51 CAG repeat and normal-size alleles underwent clinical and molecular studies. Intragenic haplotypes for these alleles were determined. A representative sample of the healthy population in the region was obtained to assess the distribution of the normal (CAG)(n) length. We established the genotype for 4 intragenic polymorphisms in the gene for MJD (MJD1) in 21 homoallelic individuals, to distinguish their 2 normal chromosomes. In addition, we developed a new Southern blot method to completely exclude cases of nonamplification of expanded alleles in the homoallelic individuals. RESULTS: The study of the family in which the 51 CAG repeat was found suggests that the allele is apparently not associated with disease. These intermediate alleles were not present in a large sample of the healthy population from the same region. Intragenic polymorphisms allowed distinction of the 2 different normal alleles in all cases of homoallelism. The absence of an expanded allele was also confirmed by Southern blot. CONCLUSIONS: We propose an improved protocol for molecular testing for MJD. These strategies, developed to overcome the practical difficulties mostly in the presymptomatic and prenatal diagnosis of MJD, should prove useful for other polyglutamine-related disorders

How typhoons trigger turbidity currents in submarine canyons

Intense turbidity currents occur in the Malaylay Submarine Canyon off the northern coast of Mindoro Island in the Philippines. They start in very shallow waters at the shelf break and reach deeper waters where a gas pipeline is located. The pipeline was displaced by a turbidity current in 2006 and its rock berm damaged by another 10 years later. Here we propose that they are triggered near the mouth of the Malaylay and Baco rivers by direct sediment resuspension in the shallow shelf and transport to the canyon heads by typhoon-induced waves and currents. We show these rivers are unlikely to generate hyperpycnal flows and trigger turbidity currents by themselves. Characteristic signatures of turbidity currents, in the form of bed shear stress obtained by numerical simulations, match observed erosion/deposition and rock berm damage patterns recorded by repeat bathymetric surveys before and after typhoon Nock-ten in December 2016. Our analysis predicts a larger turbidity current triggered by typhoon Durian in 2006; and reveals the reason for the lack of any significant turbidity current associated with typhoon Melor in December 2015. Key factors to assess turbidity current initiation are typhoon proximity, strength, and synchronicity of typhoon induced waves and currents. Using data from a 66-year hindcast we estimate a ~8-year return period of typhoons with capacity to trigger large turbidity currents

Comprehensive feature selection for classifying the treatment outcome of high-intensity ultrasound therapy in uterine fibroids

The study aim was to utilise multiple feature selection methods in order to select the most important parameters from clinical patient data for high-intensity focused ultrasound (HIFU) treatment outcome classification in uterine fibroids. The study was retrospective using patient data from 66 HIFU treatments with 89 uterine fibroids. A total of 39 features were extracted from the patient data and 14 different filter-based feature selection methods were used to select the most informative features. The selected features were then used in a support vector classification (SVC) model to evaluate the performance of these parameters in predicting HIFU therapy outcome. The therapy outcome was defined as non-perfused volume (NPV) ratio in three classes: 80%. The ten most highly ranked features in order were: fibroid diameter, subcutaneous fat thickness, fibroid volume, fibroid distance, Funaki type I, fundus location, gravidity, Funaki type III, submucosal fibroid type and urinary symptoms. The maximum F1-micro classification score was 0.63 using the top ten features from Mutual Information Maximisation (MIM) and Joint Mutual Information (JMI) feature selection methods. Classification performance of HIFU therapy outcome prediction in uterine fibroids is highly dependent on the chosen feature set which should be determined prior using different classifiers