Actividades prácticas en el contexto de las bebidas y competencia científica

Activitats pràctiques en el context de les begudes i competència científica. Les activitats pràctiques constitueixen una de les característiques distintives de l'ensenyament de la química. La introducció de les competències bàsiques com a referent curricular obliga a analitzar i repensar la finalitat d'aquest tipus d'activitats. En aquest article es descriuen diversos tipus d'activitats pràctiques dissenyades en el context de les begudes (en concret, sobre elaboració de vi) i s'analitza la seva contribució al desenvolupament de la competència científica en l'educació secundària obligatòria.Practical activities in the context drinks and scientific expertise. Practical work is one of the distinctive features of teaching chemistry. The introduction of key competences as reference to the curriculum forces us to analyse and to rethink their objectives. In this paper different kinds of practical work designed within the context of beverages (in particular, about about wine making) are described. Their contribution to the development of scientific competence in the compulsory secondary education is discussed.Las actividades prácticas constituyen una de las características distintivas de la enseñanza de la química. La introducción de las competencias básicas como referente curricular obliga a analizar y repensar la finalidad de las mismas. En este artículo se describen diversos tipos de actividades prácticas diseñadas en el contexto de las bebidas (en concreto, sobre elaboración de vino) y se analiza su contribución al desarrollo de la competencia científica en la educación secundaria obligatoria

V centers in MgAl2O4 spinels

V centers induced by ionizing irradiation at 80 or 300 K in single-crystal and polycrystalline MgAl2O4 samples have been studied by use of electron paramagnetic resonance and optical absorption. Vt- and Vo2- centers, as a result of hole trapping at tetrahedral and octahedral cation vacancies, respectively, have been found to be responsible for two EPR bands centered at g=2.011 and optical absorption bands involved in the complex absorption spectrum at about 3.4 eV. These centers anneal thermally in a very wide step from 220 to 575 K. © 1991 The American Physical SocietyPeer Reviewe

On the Lebesgue measure of Li-Yorke pairs for interval maps

We investigate the prevalence of Li-Yorke pairs for $C^2$ and $C^3$ multimodal maps $f$ with non-flat critical points. We show that every measurable scrambled set has zero Lebesgue measure and that all strongly wandering sets have zero Lebesgue measure, as does the set of pairs of asymptotic (but not asymptotically periodic) points. If $f$ is topologically mixing and has no Cantor attractor, then typical (w.r.t. two-dimensional Lebesgue measure) pairs are Li-Yorke; if additionally $f$ admits an absolutely continuous invariant probability measure (acip), then typical pairs have a dense orbit for $f \times f$. These results make use of so-called nice neighborhoods of the critical set of general multimodal maps, and hence uniformly expanding Markov induced maps, the existence of either is proved in this paper as well. For the setting where $f$ has a Cantor attractor, we present a trichotomy explaining when the set of Li-Yorke pairs and distal pairs have positive two-dimensional Lebesgue measure.Comment: 41 pages, 3 figure

Homogeneity of multinomial populations when data are classified into a large number of groups

Suppose that we are interested in the comparison of two independent categorical variables. Suppose also that the population is divided into subpopulations or groups. Notice that the distribution of the target variable may vary across subpopulations, moreover, it may happen that the two independent variables have the same distribution in the whole population, but their distributions could differ in some groups. So, instead of testing the homogeneity of the two categorical variables, one may be interested in simultaneously testing the homogeneity in all groups. A novel procedure is proposed for carrying out such a testing problem. The test statistic is shown to be asymptotically normal, avoiding the use of complicated resampling methods to get $p$-values. Here by asymptotic we mean when the number of groups increases; the sample sizes of the data from each group can either stay bounded or grow with the number of groups. The finite sample performance of the proposal is empirically evaluated through an extensive simulation study. The usefulness of the proposal is illustrated by three data sets coming from diverse experimental fields such as education, the COVID-19 pandemic and digital elevation models.Comment: 37 pages, 1 figur

Nutritional Characterization of Medicago sativa (Alfalfa) for Feeding to Ruminants

This study aimed to analyze the nutritional characteristics of Medicago sativa (Alfalfa) hay for the feeding of ruminants in the central zone of the Sierra Region. The study was conducted in the Laboratory of the Faculty of Pecaurias Sciences of the Higher Polytechnic School of Chimborazo. Cutting was carried out for 60 days in different areas of the central Sierra region. Data were analyzed using descriptive statistics. Results of the bromatological analysis showed that the average total humidity was 11.12 ± 0.20% in (Rp-00542) while the minimum was 7.79 ± 0.05% in (Rp-00224). Values for dry matter ranged between 91.25 ± 0.03% (Rp336) and 88.53 ± 0.09% (Rp492); dry base ash ranged between 12.51 ± 0.08% (Rp500) and 9.16 ± 0.08% (Rp521); dry organic matter ranged between 90.84 ± 0.13% (Rp521) and 87.49 ± 0.08% (Rp521); and dry crude protein ranged between 22.44 ± 0.26% (Rp492) and 18.73 ± 0.08% (Rp336). The following values were also obtained: 1.94 ± 0.93% dry ethereal extract; 32.06 ± 2.11% dry nitrogen free extract; 46.96 ± 3.78% dry neutral detergent fiber; 40.67 ± 3.36% dry acid detergent fiber; and 8.23 ± 0.64% dry lignin detergent acid. Therefore, it can be determined that forage mixture provides all of the nutrients to the species of zootechnical interest. Keywords: Medicago sativa, alfalfa, sierra centro, rumiants. RESUMEN En el Laboratorio de la Facultad de Ciencias Pecaurias de la Escuela Superior Politécnica de Chimborazo, se realizó la Caracterización Nutricional de henos de Medicago sativa (Alfalfa) para la alimentación de Rumiantes en la zona centro de la Región Sierra; Mediante estadística descriptiva se obtuvo los siguientes resultados del análisis bromatológico a los 60 días de corte en las diferentes zonas de la región Sierra - Centro, se puede observar que el mayor promedio de la humedad total fue 11,12 ± 0,20% en (Rp-00542) mientras que el menos fue 7,79 ± 0,05% en (Rp-00224); para Materia Seca-Total los valores se obtuvieron entre  91,25 ± 0,03% (Rp336) y 88,53 ± 0,09% (Rp492); Cenizas base seca 12,51 ± 0,08% (Rp500) y 9,16 ± 0,08% (Rp521); el mayor valor para % Materia Orgánica Base seca fue de 90,84 ± 0,13% (Rp521) y el menor con 87,49 ± 0,08% (Rp521); para % Proteína cruda base seca la mejor respuesta fue 22,44 ± 0,26 (Rp492) % y el menor  18,73 ± 0,08 (Rp336), Fibra cruda base seca; 1,94 ± 0,93% Extracto etéreo base seca; 32,06 ± 2,11% Extracto Libre de Nitrógeno base seca; 46,96 ± 3,78% Fibra Detergente Neutro base seca; 40,67 ± 3,36% Fibra Detergente Acida base seca; 8,23 ± 0,64% Lignina Detergente Acida base seca. Por lo que se puede determinar que la mezcla forrajera aporta todos los nutrientes a todas las especies de interés zootécnico. Palabras clave: Medicago sativa, alfalfa, sierra centro, rumiantes

Systematic identification of phenotypically enriched loci using a patient network of genomic disorders

Background Network medicine is a promising new discipline that combines systems biology approaches and network science to understand the complexity of pathological phenotypes. Given the growing availability of personalized genomic and phenotypic profiles, network models offer a robust integrative framework for the analysis of "omics" data, allowing the characterization of the molecular aetiology of pathological processes underpinning genetic diseases. Methods Here we make use of patient genomic data to exploit different network-based analyses to study genetic and phenotypic relationships between individuals. For this method, we analyzed a dataset of structural variants and phenotypes for 6,564 patients from the DECIPHER database, which encompasses one of the most comprehensive collections of pathogenic Copy Number Variations (CNVs) and their associated ontology-controlled phenotypes. We developed a computational strategy that identifies clusters of patients in a synthetic patient network according to their genetic overlap and phenotype enrichments. Results Many of these clusters of patients represent new genotype-phenotype associations, suggesting the identification of newly discovered phenotypically enriched loci (indicative of potential novel syndromes) that are currently absent from reference genomic disorder databases such as ClinVar, OMIM or DECIPHER itself. Conclusions We provide a high-resolution map of pathogenic phenotypes associated with their respective significant genomic regions and a new powerful tool for diagnosis of currently uncharacterized mutations leading to deleterious phenotypes and syndromes