Sobre algunos errores comunes en desarrollos algebraicos.

En este documento se muestran los resultados de una investigación cuyo objetivo era describir algunos tipos de errores que, con mayor frecuencia, presentan los alumnos en los primeros cursos de pre-grado cuando pretenden solucionar ejercicios que requieren manipulaciones algebraicas; además, se trató de identificar las posibles fuentes del error y establecer una alternativa metodológica que permitiera minimizar la presencia de estos tipos de errores.This paper presents the results of a research which attempted to describe some types of mistakes first semester undergraduate students frequently show when they want to find solutions for problems that need algebraic manipulations. In addition, the study aimed at identifying some possible mistakes sources and proposing a methodological alternative way in order to minimize these mistakes

Sistema de ejercicios y problemas de Matemática para la carrera de Ingeniería Agrónoma.

To achieve the training of agronomical engineers that are able to perform their role in modern production it is necessary to organize the continuous preparation of the students in the field of mathematics. In the classes of Mathematics I that are taught in this career it is evident the insufficient contextualization of the contents of the discipline within the social object and field of the profession; that is, it is still insufficient the use of the processes and phenomena object of study of this career to develop the contents of the different subjects of the discipline Mathematics. For this reason the current article is aimed at designing a system of exercises and problems for Mathematics I that were contextualized for the students majoring in Agronomy, in order to favor the agronomical engineer’s wholesome training. The system of exercises was used in the first semester of the last academic year with the students of the first year of this career with satisfactory results.Para lograr la formación de Ingenieros Agrónomos capaces de desplegar su actividad en la producción moderna se hace necesario organizar la preparación ininterrumpida de los estudiantes en el campo de las matemáticas. En las clases de Matemática I para esta carrera se evidencia insuficiente profesionalización de los contenidos de la disciplina con el objeto social y esferas de la profesión, es decir, es insuficiente el aprovechamiento de los procesos y fenómenos objeto de estudio de esta carrera para desarrollar, a través de ellos, los contenidos de las diferentes asignaturas de la Matemática, es por ello que este trabajo tiene como objetivo la elaboración de un sistema de ejercicios y problemas de Matemática I contextualizados a la carrera de Agronomía, en función de favorecer la formación integral del ingeniero agrónomo. El sistema de ejercicios se utilizó en el primer semestre de actual curso con los estudiantes del primer año de esta carrera con resultados satisfactorios

Oscar Vivero Reyes: insigne pedagogo granmense.

The work presented constitutes a homage to the exceptional educator Oscar Vivero Reyes, who dies on March 11th, of the present year, in the sister Bolivarian Republic of Venezuela, victim of the Covid, illness that continues whipping Cuba and the world. For the elaboration of this work, the authors took into consideration the summing up of  the biographical data which was a contribution from his family (his handcuffs and daughter), the pain expressions manifested by the university community of Granma Province , his students,  professors,  friends and other people that met him and shared with him during his life. The Roca Magazine carries out this publication to express the human values of someone who besides been an excellent professional, also was an active member of this Editorial Committee. It is also included a synthesis of his labor trajectory. El trabajo que se presenta constituye un homenaje al excepcional pedagogo Oscar Vivero Reyes, quien fallece el 11 de marzo del presente año en la hermana República Bolivariana de Venezuela, víctima de la covid, enfermedad que continúa azotando a Cuba y al mundo. Para su elaboración se contó con la recopilación de datos biográficos que aportó su familia (esposa e hija), las expresiones de dolor manifestadas por la comunidad educacional granmense, sus alumnos, sus profesores, sus amigos y otras personas que lo conocieron y compartieron con él en vida. La revista ROCA realiza esta publicación para dar a conocer los valores humanos de quien además de un excelente profesional, fue un activo miembro de su Comité Editorial. Se incluye además una síntesis de su trayectoria laboral

Modelo matemático para estimação do sinal utilizando filtro de wiener: ferramenta para estudantes de sistemas de comunicações (Original)

The training of students in communications systems is a challenge for the teachers responsible for conducting this process. The absence of a practical demonstration of signal estimation in the communication systems stimulated the execution of this work. For the research, it was taken as field of action, the filter of Wiener. The objective of the work was to provide a practical tool for students in this area. The tool consists of the description of the mathematical model to obtain the Wiener filter equation. An example for determining the optimal filter is also shown. In the work, the Wiener filter simulation using the Matlab program was carried out. In short, the tool allows the deepening of knowledge with greater efficiency and in a practical way.A capacitação de estudantes de sistemas de comunicações é um desafio para os professores encargados da condução de este processo. A ausência de poder demostrar de forma pratica a estimação de sinal nos sistemas de comunicações estimulou à realização de este trabalho. Para a investigação tomou-se como campo de ação, o filtro de Wiener. O objetivo do trabalho foi fornecer uma ferramenta pratica para estudantes nesta área. A ferramenta consiste na descrição do modelo matemático para a obtenção da equação do filtro de Wiener. Também é mostrado um exemplo para a determinação do filtro ótimo. No trabalho realizou-se a simulação de filtro de Wiener utilizando o programa Matlab. Conclui-o que a ferramenta permite a profundização dos conhecimentos com maior eficiência e de forma pratica

LA MODELACIÓN MATEMÁTICA EN SU ESTRUCTURACIÓN DE UN SISTEMA DE HABILIDADES (Original)

The mathematical modeling is one of the fundamental tools that it allows to the engineer to correctly interpret of  the reality and transform it in order to perfect the different processes of the economy. The present paper aims to offer a methodology to improve the teaching of the mathematical modeling through differential equations in the Engineering careers of the Faculty of Technical Sciences of Granma's University. A thorough analysis of the curricula of these careers and the preparation of teachers and students identified the main inadequacies in this subject. The proposed methodology is based in the structuring of the mathematical basic abilities and its influence for the formation and develops of the ability to model through differential equations and in the contextualization of the teaching problems so that they motivate the students to the efficient study of this content.La modelación matemática es una de las herramientas fundamentales que le permite al ingeniero interpretar de forma correcta la realidad y transformarla en aras de perfeccionar los distintos procesos de la economía. El presente trabajo tiene como objetivo ofrecer una metodología para contribuir al perfeccionamiento de la enseñanza de la modelación matemática, vía ecuaciones diferenciales en las carreras de Ingeniería de la facultad de Ciencias Técnicas de la Universidad de Granma. Mediante un análisis minucioso de los planes y programas de estudio de estas carreras, de la preparación de los docentes y de los estudiantes se determinaron las principales insuficiencias en esta temática. La metodología propuesta se sustenta en la estructuración de las habilidades matemáticas básicas y su influencia para la formación y desarrollo de la habilidad modelar vía ecuaciones diferenciales y en la contextualización de los problemas docentes de manera que motiven a los estudiantes al estudio eficiente de este contenido

Mutation prevalence of cerebral cavernous malformation genes in Spanish patients

[Objective] To study the molecular genetic and clinical features of cerebral cavernous malformations (CCM) in a cohort of Spanish patients.[Methods] We analyzed the CCM1, CCM2, and CCM3 genes by MLPA and direct sequencing of exons and intronic boundaries in 94 familial forms and 41 sporadic cases of CCM patients of Spanish extraction. When available, RNA studies were performed seeking for alternative or cryptic splicing.[Results] A total of 26 pathogenic mutations, 22 of which predict truncated proteins, were identified in 29 familial forms and in three sporadic cases. The repertoire includes six novel non-sense and frameshift mutations in CCM1 and CCM3. We also found four missense mutations, one of them located at the third NPXY motif of CCM1 and another one that leads to cryptic splicing of CCM1 exon 6. We found four genomic deletions with the loss of the whole CCM2 gene in one patient and a partial loss of CCM1and CCM2 genes in three other patients. Four families had mutations in CCM3. The results include a high frequency of intronic variants, although most of them localize out of consensus splicing sequences. The main symptoms associated to clinical debut consisted of cerebral haemorrhage, migraines and epileptic seizures. The rare co-occurrence of CCM with Noonan and Chiari syndromes and delayed menarche is reported.[Conclusions] Analysis of CCM genes by sequencing and MLPA has detected mutations in almost 35% of a Spanish cohort (36% of familial cases and 10% of sporadic patients). The results include 13 new mutations of CCM genes and the main clinical symptoms that deserves consideration in molecular diagnosis and genetic counselling of cerebral cavernous malformations.This work has been supported by grants CP10/00526 (Instituto de Salud Carlos III, Spain) and P07-CVI-02790 (Junta de Andalucía, Spain). RM received a fellowship of José Luis Castaño Foundation.Peer Reviewe

LA LABOR EDUCATIVA EN EL PROCESO PEDAGÓGICO DEL PREUNIVERSITARIO. UN ACERCAMIENTO A SUS ANTECEDENTES

This article refers to the historical antecedents of the pedagogic process of the senior high school, with emphasis in the educative work. This aspect is approached from the emergence of the internal senior high school until the present time. The conception of the content of the educational work is also analyzed, as well as the methods and means used for this work in the different defined stages. It is also exposed, the emergence of the formative objectives, you program directors and traverse axes for the educational exit to the educational work in this education, as well as the conceptions about the pattern of the senior high school in the last decade. Finally, they refer the tendencies that are manifested in the educative work in correspondence with the established indicators for the analysis.  Este artículo hace referencia a los antecedentes históricos del proceso pedagógico del preuniversitario, con énfasis en la labor educativa. Se aborda este aspecto desde el surgimiento de los preuniversitarios internos hasta la actualidad. También se analiza la concepción del contenido de la labor educativa, así como los métodos y medios usados para esta labor en las diferentes etapas delimitadas. Se expone además, el surgimiento de los objetivos formativos, programas directores y ejes transversales para la salida docente a la labor educativa en esta educación, así como las concepciones acerca del modelo del preuniversitario en la última década. Finalmente se refieren las tendencias que se manifiestan en la labor educativa en correspondencia con los indicadores establecidos para el análisis

Mutation Prevalence of Cerebral Cavernous Malformation Genes in Spanish Patients

Objective: To study the molecular genetic and clinical features of cerebral cavernous malformations (CCM) in a cohort of Spanish patients. Methods: We analyzed the CCM1, CCM2, and CCM3 genes by MLPA and direct sequencing of exons and intronic boundaries in 94 familial forms and 41 sporadic cases of CCM patients of Spanish extraction. When available, RNA studies were performed seeking for alternative or cryptic splicing. Results: A total of 26 pathogenic mutations, 22 of which predict truncated proteins, were identified in 29 familial forms and in three sporadic cases. The repertoire includes six novel non-sense and frameshift mutations in CCM1 and CCM3. We also found four missense mutations, one of them located at the third NPXY motif of CCM1 and another one that leads to cryptic splicing of CCM1 exon 6. We found four genomic deletions with the loss of the whole CCM2 gene in one patient and a partial loss of CCM1and CCM2 genes in three other patients. Four families had mutations in CCM3. The results include a high frequency of intronic variants, although most of them localize out of consensus splicing sequences. The main symptoms associated to clinical debut consisted of cerebral haemorrhage, migraines and epileptic seizures. The rare co-occurrence of CCM with Noonan and Chiari syndromes and delayed menarche is reported. Conclusions: Analysis of CCM genes by sequencing and MLPA has detected mutations in almost 35% of a Spanish cohort (36% of familial cases and 10% of sporadic patients). The results include 13 new mutations of CCM genes and the main clinical symptoms that deserves consideration in molecular diagnosis and genetic counselling of cerebral cavernous malformations.Instituto de Salud Carlos III CP10/00526Junta de Andalucía P07-CVI-02790Fundación José Luis Castañ

Evaluating taxonomic inflation: towards evidence-based species delimitation in Eurasian vipers (Serpentes: Viperinae)

International audienceThe designation of taxonomic units has important implications for the understanding and conservation ofbiodiversity. Eurasian vipers are a monophyletic group of viperid snakes (Serpentes, Viperinae), currently comprising fourgenera (Daboia, Macrovipera, Montivipera and Vipera) and up to 40 species. Taxonomic units have been described usinga wide variety of methods and criteria, and consequently, considerable controversy still surrounds the validity of somecurrently listed species. In order to promote a consensus- and evidence-based taxonomy of Eurasian vipers, we analysedpublished mitochondrial and nuclear DNA sequences for this group to reconstruct phylogenetic relationships among currentlyrecognized viper species.We also compiled information on external morphology to assess their morphological distinctiveness.Phylogenetic inference based on mtDNA sequences shows contrasting levels of divergence across genera and species andidentifies several instances of non-monophyly in described species. Nuclear DNA sequences show extremely low levels ofgenetic variation, with a widespread pattern of allele sharing among distant species, and even among genera. Revision ofmorphological data shows that most species designations rely on scalation traits that overlap extensively among species ofthe same genus. Based on our combined assessment, we recognize 15 taxa as valid species, three taxa which likely representspecies complexes, 17 taxa of doubtful validity as species, and five taxa for which species status is maintained but furtherresearch is highly recommended to assess taxonomic arrangements. We stress the need to implement integrative taxonomicapproaches for the recognition of evidence-based taxonomic units in Eurasian viper