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Initial Stages in the Formation of Galls Induced by Geoica utricularia in Pistacia terebinthus Leaflets: Origin of the Two Vascular Bundles which Characterize the Wall of the Galls  [PDF]
álvarez Nogal
American Journal of Plant Sciences (AJPS) , 2011, DOI: 10.4236/ajps.2011.22019
Abstract: Only a few species of aphids induce galls. Among these, Paracletus cimiciformis, Forda marginata, Forda formicaria, Geoica utricularia and Baizongia pistaciae induce galls on Pistacia terebinthus leaflets. Prior to present study the author examined microscopically P. terebinthus leaflets. He also studied the microscopic morphology of galls induced by the five species mentioned above. A clear microscopic difference between these galls is that in the wall of galls induced by the genera Paracletus and Forda a single vascular bundle is seen. The interpretation is that these galls are laminae of the modified leaflets. However, in the walls of the galls induced by the genera Geoica and Baizongia, two vascular bundles are observed. In the present paper a study of the early stages of development of galls produced by G. utricularia is described. The study was designed to explain the origin of the two vascular bundles present in the walls of these galls. The findings indicate that the aphid induces a massive development of the two vascular bundles present in the midvein of the leaflets of P. terebinthus: the main vascular bundle and the small supernumerary vascular bundle. Both these extremely developed vascular bundles occupy the walls of the galls induced by G. utricularia.
Homological Electromagnetism and Electromagnetic Demonstrations on the Existence of Superconducting Effects Necessaries to Magnetic Levitation/Suspension  [PDF]
Francisco Bulnes, Antonio álvarez
Journal of Electromagnetic Analysis and Applications (JEMAA) , 2013, DOI: 10.4236/jemaa.2013.56041
Abstract:

Considering results obtained in magnetic levitation and suspension of the symmetrical bodies are designed and developed several experiments of the electromagnetism that demonstrate the effects of a superconductor necessary to the magnetic levitation/suspension. This generates bases to the development of a reactor to impulse and anti-gravitational magnetic displacement of a vehicle considering the production and transference of Eddy currents on their structure to microscopic level and the effect of auto-levitation/auto-suspension that is obtained with the iso-rotations of the impulse magnetic ring of the proper vehicle.

Promover el aprendizaje de la competencia escritora: secuencias en las que se combina el trabajo individual y el trabajo cooperativo.
Manuela álvarez álvarez
REDU : Revista de Docencia Universitaria , 2011,
Abstract: RESUMEN El proceso de Convergencia Europea nos conduce a un modelo de ense anza universitaria en el que el protagonista principal es el sujeto que aprende. Dentro de este marco el dise o de un programa formativo centrado en el desarrollo de la competencia escritora y adaptado al crédito europeo tiene implicaciones importantes en el trabajo del profesor. En estas páginas me voy a referir únicamente a aquellas que suponen el dise o de técnicas o procedimientos que debidamente coordinados permitan integrar el trabajo del alumno dentro y fuera del aula de manera que pueda alcanzar los objetivos previamente establecidos. ABSTRACT The process of European Convergence prioritises a university teaching model in which the main protagonist is the learning individual. Within this frame the design of a formative programme centred on the development of the writing skills and adpated to the European Credit System implies important consequences for the teacher’s work. In the following pages I will refer only to those which involve the design of techniques or procedures which properly coordinated allow for the integration the student′s work inside and outside the class so that the previously established objectives can be achieved.
La protección jurídica de las ciudades históricas
álvarez álvarez, José Luis
Arbor : Ciencia, Pensamiento y Cultura , 2001,
Abstract: Not available No disponible
FACTORES DE RIESGO VASCULAR: REGISTRO EXTRAINSTITUCIONAL EN LA LOCALIDAD DE ENCRUCIJADA / Vascular Risk factors: extra-institutional registry in Encrucijada municipality
Gerardo álvarez álvarez
CorSalud , 2010,
Abstract: Resumen Introducción y objetivos: El conocimiento de los factores de riesgo vascular es de gran importancia para la preservación de la salud poblacional, ellos contribuyen al desarrollo de la aterosclerosis, sustrato necesario para ocasionar da os en el corazón, cerebro, ri ón y vasos periféricos. El objetivo de esta investigación fue realizar un pesquisaje de un segmento poblacional en la búsqueda de estos factores de riesgo. Métodos: Se realizó una investigación de carácter analítico-transversal, de forma extrainstitucional a las unidades médicas, sobre factores de riesgo vascular en la localidad de Encrucijada, Villa Clara, en mayo del 2009. Resultados: Se habilitaron 10 puntos de registros en lugares concurridos por la población; en un lapso de 4 horas se alcanzó una casuística de 697 personas, con un predominio de mujeres y de personas con color de la piel blanca. La talla media poblacional fue de 1,64 cm, los valores promedios de peso corporal, índice de masa corporal y de la cintura abdominal fueron de: 67 kg, 25 kg/m2 y 86,3 cm. La hipertensión arterial fue encontrada en el 16 % de los casos, con mayor porcentaje en individuos con poca actividad física, en los de mayor índice de masa corporal y cintura abdominal, y con color negro de la piel. La adicción tabáquica fue superior en hombres. Se constató una notable aceptación poblacional. Conclusiones: Nuestro estudio demuestra la presencia de factores de riesgo vascular en un segmento de la población del municipio Encrucijada y nos alertan sobre la necesidad de fortalecer la medicina comunitaria (promoción y prevención) para mejorar la salud de todos. / Abstract Introduction and objectives: The knowledge of vascular risk factors is of great importance in the preservation of the population's health as they contribute to the development of atherosclerosis which is a necessary substratum to produce damages in the heart, brain, kidney and peripheral vessels. This investigation aimed at carrying out a screening of one population segment in search for these risk factors. Methods: An analytical, cross-sectional investigation on vascular risk factors was carried out in an extra-institutional form (outside medical units) in Encrucijada municipality, Villa Clara, in May, 2009. Results: Ten registry points were set up in well-attended places and in a 4 hour-period a casuistics of 697 people was achieved, in which there was a predominance of women and white people. The mean population height was 1.64 cm, and the average values of weight, body mass index and waist circumference were: 67 kg, 25 kg/m2 and 86.3 c
Robust Differentiable Functionals for the Additive Hazards Model  [PDF]
Enrique E. álvarez, Julieta Ferrario
Open Journal of Statistics (OJS) , 2015, DOI: 10.4236/ojs.2015.56064
Abstract:

In this article, we present a new family of estimators for the regression parameter β in the Additive Hazards Model which represents a gain in robustness not only against outliers but also against unspecific contamination schemes. They are consistent and asymptotically normal and furthermore, and they have a nonzero breakdown point. In Survival Analysis, the Additive Hazards Model proposes a hazard function of the form \"\", where \"\"?is a common nonparametric baseline hazard function and z is a vector of independent variables. For this model, the seminal work of Lin and Ying (1994) develops an estimator for the regression parameter β which is asymptotically normal and highly efficient. However, a potential drawback of that classical estimator is that it is very sensitive to outliers. In an attempt to gain robustness, álvarez and Ferrarrio (2013) introduced a family of estimators for β which were still highly efficient and asymptotically normal, but they also had bounded influence functions. Those estimators, which are developed using classical Counting Processes methodology, still retain the drawback of having a zero breakdown point.

The Hypothesis of Hyperia from the Perspective of Neuronal Plasticity  [PDF]
Javier álvarez-Rodríguez
Open Journal of Medical Psychology (OJMP) , 2016, DOI: 10.4236/ojmp.2016.51003
Abstract: We analyze certain mental automatisms appearing in the consciousness with phenomenological features of simple partial seizures (SPSs). We propose to include all these phenomena into a cognitive function to which we term hyperia. In this paper, we analyze the similarities between the nature of this cognitive function and the mechanisms used by our brain to elicit neuronal plasticity.
Análisis del discurso del aula desde el enfoque comunicativo-interactivo de la argumentación
álvarez,Guadalupe;
Forma y Función , 2008,
Abstract: using a communicative-interactive approach to argumentation (plantin, 1996, 1998a, 1998b), the objective of the present article is to determine the features of the discourse in situations of disagreement between the teacher and her students. to fulfill this goal, this article analyzes communicative interactions in language courses of the basic general education (egb). disagreements and their developments are identified in order to determine whether these are adjustment or negotiation, or whether an argumentative situation is established. based on the analysis, it is concluded that the educator strives to maintain her point of view in spite of students' disagreements. nevertheless, it is argued that their self-image is not affected due to the teacher's use of various resources and linguistic strategies that range from adjustment to negotiation to the generation of what is called a "potential argumentative situation".
Mejoremos el discurso narrativo de nuestros alumnos
álvarez,Luis;
Investigación y Postgrado , 2008,
Abstract: the paper summarizes the structure and functionality of a research project that had as its main goal improving the narrative discourse of those participating in the application of this methodology. at the theoretical level, a model was developed to establish certain analytical conditions needed to produce narrative texts. the texts were produce in two different settings. in the first one, subjects were given a graphic sequence. in the second one, situations were brought about to induce the subjects to be creative and applied the structures learned. at the descriptive level, the intention was to find proof that the problem situation, found in the study groups, could be overcome by implementing what this study proposes. at the methodological level, it was considered that such implementation could be summarized in several rules which, used flexibly -depending on the participating group and its level-, could lead to the solution to those problems detected at institutions where writing, production and improvement topics are tackled. for the epistemological approach, we have started from a general theory, parson and shils?s (1961) general theory of action, since we considered writing to be a particular case of an action. at the same time, two intermediate theories were used: habermas? theory of communicative actions (1987), and padrón?s theory of integrated actions (1993). finally, we have also applied, when appropriate, two specific language theories: transformational grammar (chomsky, 1970) and text linguistics (van dijk, 1989, 1990, 1994, 1998).
El interés de la etnografía escolar en la investigación educativa
álvarez,Carmen;
Estudios pedagógicos (Valdivia) , 2011, DOI: 10.4067/S0718-07052011000200016
Abstract: various alternative perspectives in educational research have emerged in relation to positivist research approaches. one is the school ethnography, which focuses on the study of culture promoted in schools and classrooms. this article raises the interest of researchers in using this model for research and attempts to answer fundamental questions of this model of research: what do we mean by school ethnography; what features it has; what’s the role of the researcher; what are the main moments; how to validate ethnographic research; and what is its progress when compared to other research models.
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