Modelo para el análisis de una aptitud cognitiva para el aprendizaje

La investigación en el campo de las aptitudes cognitivas para el aprendizaje requiere una forma de abordarlas y definir sus características y componentes. A su vez, esta definición debe conducir al investigador a la creación de pruebas de medición que ayuden al análisis de este tipo de aptitudes y su relación con otras variables del aprendizaje. Para dar respuesta a esas necesidades, el objetivo de este artículo es proponer la creación de un modelo para el análisis de una aptitud cognitiva para el aprendizaje, cuya estructura conste de cuatro elementos principales. Dos de ellos relacionados con los enfoques y consideraciones para emprender su estudio; los otros dos, con la definición de la aptitud, a través de sus características y sus componentes

Causas célebres. Crimen y liberalismo en la prensa mexicana del siglo XIX

En la prensa de la Ciudad de México durante el periodo que abarca desde principios del siglo XIX hasta la segunda década del Porfiriato fueron publicadas las denominadas causas célebres, relatos de crímenes de la época, que constituyen un género entre el periodismo y la literatura popular, las cuales se articulan como testimonio de la transformación del discurso sobre el crimen realizado por las élites mexicanas, en especial las adscritas al liberalismo. En el presente trabajo se realiza un análisis de los elementos que el discurso liberal dentro de las causas célebres emplea para interpretar el crimen y configurarlo en el imaginario social, en particular en La causa contra los asesinos de Florencio Egerton y Doña Inés Edwards cuyo seguimiento fue dado por diarios como El Observador judicial y El Siglo Diez y Nueve (cuyo nombre fue El Memorial Histórico de 1842 a 1843

Prevalencia de factores asociados a la enfermedad cardiovascular y su relación con el ausentismo laboral de los trabajadores de una entidad oficial

Introduction: Cardiovascular disease is the first cause of death in the world. This phenomenon is attributed to life styles, such a sedentarism, ingestion of high calorie foods, and alcohol and tobacco consumption. This leads to an increase in the rates of obesity, dyslipidaemia, and hypertension. These then become risk factors that directly affect the prevalence of disease and death of cardiovascular origin, which consequently represents a significant health problem in the working population. Objective: To determine the factors associated with cardiovascular disease and their relationship with work absenteeism in a government office in the City of Bogota, Colombia. Materials and methods: A descriptive study was carried out using the work records of 214 employees. Sociodemographic, clinical-cardiovascular, and work variables were also recorded. An analysis was performed on the independent variables and the outcome, and a logistic regression model was prepared using work absenteeism as a dependent variable. Results: The prevalences of the sample were: smoking, 13.1%; alcohol consumption, 35.1%; sedentarism, 39.7%; overweight or obese workers, 54.2%; and elevated total cholesterol, 43.9%. Treatment was being received for hypertension in 29.9%, with 4.7% for diabetes, and 21.5% for lipid disorders. Conclusion: The prevalence of risk factors associated with cardiovascular disease is similar to that found in other studies on the working population. The regression model showed that the variables marital status, obesity, treatment for hypertension, diastolic blood pressure level, and length of service, behaved as predictive variables of work absenteeism. © 2019 Sociedad Colombiana de Cardiología y Cirugía Cardiovascula

Chiralities of nodal points along high symmetry lines with screw rotation symmetry

Screw rotations in nonsymmorphic space group symmetries induce the presence of hourglass and accordion shape band structures along screw invariant lines whenever spin-orbit coupling is nonnegligible. These structures induce topological enforced Weyl points on the band intersections. In this work we show that the chirality of each Weyl point is related to the representations of the cyclic group on the bands that form the intersection. To achieve this, we calculate the Picard group of isomorphism classes of complex line bundles over the 2-dimensional sphere with cyclic group action, and we show how the chirality (Chern number) relates to the eigenvalues of the rotation action on the rotation invariant points. Then we write an explicit Hamiltonian endowed with a cyclic action whose eigenfunctions restricted to a sphere realize the equivariant line bundles described before. As a consequence of this relation, we determine the chiralities of the nodal points appearing on the hourglass and accordion shape structures on screw invariant lines of the nonsymmorphic materials PI3 (SG: P63), Pd3N (SG: P6322), AgF3 (SG: P6122) and AuF3 (SG: P6122), and we corroborate these results with the Berry curvature and symmetry eigenvalues calculations for the electronic wavefunction.Comment: 10 pages, 4 figure

Seguridad hospitalaria, una visión de seguridad multidimensional: Hospital security. A vision of multidimensional security

The risks during the performance of work is an inherent situation to any human activity. Hospital Safety is defined as: “the condition that guarantees that the workers, patients, visitors, infrastructure and equipment within a health care center are free of risk or danger of accidents”. The construction of the prevention culture starts from the knowledge of the risks, the safety culture is directly related to the quality of care of the service provided, which is why these terms are of special interest in health institutions. Talking about comprehensive risk management, either, involves determining all the risks that could cause considerable damage to these systems, given by the interaction of three factors, the presence of a threat, the existence of vulnerabilities and the time they are exposed to. Thus we can distinguish that hospital safety must be an internal policy of every health institution and that it can be divided into three main axes: 1. Patient safety, 2. Comprehensive risk management for major emergencies and disasters, 3. Internal safety and external to violence.Los riesgos durante el desempeño del trabajo es una situación inherente a cualquier actividad humana. La Seguridad Hospitalaria se define como: “la condición que garantiza que los trabajadores, pacientes, visitantes, infraestructura y equipos dentro de un centro de atención en salud, estén libres de riesgo o peligro de accidentes”. La construcción de la cultura de prevención parte del conocimiento de los riesgos, la cultura de la seguridad se encuentra directamente relacionada con la calidad de atención del servicio que se otorga, por lo cual en las instituciones de salud estos términos son de especial interés. Hablar de gestión integral de riesgos implica determinar todos los riesgos que pudieran provocar un daño considerable a estos sistemas, dado por la interacción de tres factores, la presencia de una amenaza, la existencia de vulnerabilidades y el tiempo a exposición a estos. Así podemos distinguir que la seguridad hospitalaria debe ser una política interna de toda institución de salud y que se puede dividir en tres grandes ejes: 1. Seguridad del paciente, 2. Gestión integral de riesgos de emergencias mayores y desastres, 3. Seguridad interna y externa ante violencia

Quasinodal lines in rhombohedral magnetic materials

A well-established result in condensed matter physics states that materials crystallizing in symmetry groups containing glide reflection symmetries possess nodal lines on the energy bands. These nodal lines are topologically protected and appear on the fixed planes of the reflection in reciprocal space. In the presence of inversion symmetry, the energy bands are degenerate and the band crossings on the fixed plane may be one-dimensional, or may intersect in points, including the case of empty intersection. In the latter case, the crossing is partially or totally avoided, thus producing lines on reciprocal space where the energy gap may be small, and in the former, the nodal lines will endure, thus producing Dirac or double nodal lines. In addition, if the material crystallizes in a ferromagnetic phase where the glide reflection symmetry is broken, the nodal lines hybridize, thus defining lines in reciprocal space where the energy gap may be small. In this work, we concentrate our efforts on the study of nodal lines that hybridize due to magnetization; we have coined the term of quasinodal lines for those lines in reciprocal space where the energy gap is small (less than what can be detected experimentally ∼25 meV). We study magnetic trifluorides and trioxides which crystallize in magnetic space groups 167.107 and 161.71 and we show the existence of quasinodal lines on these materials. We furthermore show that whenever the quasinodal lines are located around the Fermi level then interesting charge and spin transport effects are induced and can be used to detect experimentally these lines. Of particular interest are the half-metallic ferromagnetic phases of PdF3 and LiCuF3 where the large signal of the anomalous Hall conductance is due to the presence of the quasinodal lines on the Fermi level

Topological electronic structure and Weyl points in nonsymmorphic hexagonal materials

Using topological band theory analysis we show that the nonsymmorphic symmetry operations in hexagonal lattices enforce Weyl points at the screw-invariant high-symmetry lines of the band structure. The corepresentation theory and connectivity group theory show that Weyl points are generated by band crossings in accordion-like and hourglass-like dispersion relations. These Weyl points are stable against weak perturbations and are protected by the screw rotation symmetry. Based on first-principles calculations we found a complete agreement between the topological predicted energy dispersion relations and real hexagonal materials. Topological charge (chirality) and Berry curvature calculations show the simultaneous formation of Weyl points and nodal-lines in 4d transition-metal trifluorides such as AgF3 and AuF3. Furthermore, a large intrinsic spin-Hall conductivity was found due to the combined strong spin-orbit coupling and multiple Weyl-point crossings in the electronic structure. These materials could be used to the spin/charge conversion in more energy-efficient spintronic devices