oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

3 ( 1 )

2020 ( 3 )

2019 ( 67 )

2018 ( 93 )

Custom range...

Search Results: 1 - 10 of 58596 matches for " ANTONIO; BERNAL GONZáLEZ "
All listed articles are free for downloading (OA Articles)
Page 1 /58596
Display every page Item
Patrones de presencia y abundancia de aves terrestres en la isla Saliaca, Sinaloa, México
Castillo-Guerrero, José Alfredo;González-Medina, Erick;González-Bernal, Marco Antonio;
Revista mexicana de biodiversidad , 2009,
Abstract: we determined the abundance and taxonomic composition of land-birds in saliaca island, sinaloa, mexico, by means of point counts during 3 sampling periods (summer, autumn and winter) and 3 types of habitat (thorn forest, mangrove and dune). we observed 82 species, which is greater than the number reported for any other island of the gulf of california. the species richness and abundance were greater in autumn (59 species and 9.2 ± 1.2 birds per point count) and winter (48 and 7.5 ± 0.9) than in summer (33 and 5.2 ± 0.3), a pattern resulting from the arrival of neotropical migrants. with regard to differences by habitat, the greatest richness and abundance occurred in the thorn forest (60 species and 9.3 ± 0.9 birds per point), followed by mangrove (16 and 3.3 ± 0.8) and dune (3 and 1.0 ± 0.2), which is agreement with the higher complexity of vegetation structure and the greater area of thorn forest. saliaca island could represent a relict of the coastal regional habitat, which enhances its conservation and protection value.
Patrones de presencia y abundancia de aves terrestres en la isla Saliaca, Sinaloa, México Patterns of occurrence and abundance of land birds on Saliaca Island, Sinaloa, Mexico
José Alfredo Castillo-Guerrero,Erick González-Medina,Marco Antonio González-Bernal
Revista mexicana de biodiversidad , 2009,
Abstract: Se determinó la abundancia y composición taxonómica de las aves terrestres en la Isla Saliaca, Sinaloa, México, mediante puntos de conteo en 3 periodos de muestreo (verano, oto o e invierno) y 3 tipos de hábitat (bosque espinoso, manglar y duna). Se observaron 82 especies, un número más alto que el registrado para cualquier otra isla del golfo de California. La riqueza y abundancia fueron mayores en oto o (59 especies, 9.2 ± 1.2 aves por punto) e invierno (48 y 7.5 ± 0.9) que en verano (33 y 5.2 ± 0.3); este patrón refleja el arribo de aves migrantes neotropicales. En cuanto a los tipos de hábitat, la mayor riqueza y abundancia se encontró en el bosque espinoso (60 especies y 9.3 ± 0.9 aves por punto), seguida por manglar (16 y 3.3 ± 0.8) y duna (3 y 1.0 ± 0.2), lo cual es acorde con la estructura vegetal más compleja y la área de cobertura mayor del bosque espinoso. La isla Saliaca puede representar un relicto del hábitat costero regional, por lo que es importante su protección y conservación. We determined the abundance and taxonomic composition of land-birds in Saliaca Island, Sinaloa, Mexico, by means of point counts during 3 sampling periods (summer, autumn and winter) and 3 types of habitat (thorn forest, mangrove and dune). We observed 82 species, which is greater than the number reported for any other Island of the Gulf of California. The species richness and abundance were greater in autumn (59 species and 9.2 ± 1.2 birds per point count) and winter (48 and 7.5 ± 0.9) than in summer (33 and 5.2 ± 0.3), a pattern resulting from the arrival of neotropical migrants. With regard to differences by habitat, the greatest richness and abundance occurred in the thorn forest (60 species and 9.3 ± 0.9 birds per point), followed by mangrove (16 and 3.3 ± 0.8) and dune (3 and 1.0 ± 0.2), which is agreement with the higher complexity of vegetation structure and the greater area of thorn forest. Saliaca Island could represent a relict of the coastal regional habitat, which enhances its conservation and protection value.
Breast Imaging: How We Manage Diagnostic Technology at a Multidisciplinary Breast Center
Alejandro Tejerina Bernal,Antonio Tejerina Bernal,Francisco Rabadán Doreste,Ana De Lara González,Juan Antonio Roselló Llerena,Armando Tejerina Gómez
Journal of Oncology , 2012, DOI: 10.1155/2012/213421
Abstract: This paper discusses the most important aspects and problems related to the management of breast cancer imaging, at a center specialized in breast pathology. We review the established and emerging diagnostic techniques, their indications, and peculiarities: digital mammography, CAD systems, and the recent digital breast tomosynthesis, ultrasound and complementary elastography, molecular imaging techniques, magnetic resonance imaging, advanced sequences (diffusion), and positron emission mammography (PEM). The adequate integration and rational management of these techniques is essential, but this is not always easy, in order to achieve a successful diagnosis. 1. Introduction Breast cancer remains the most prevalent cancer disease in women of developed countries with great social and economic impact. For all these reasons, the scientific community concentrates on improving imaging methods, developing drugs for new therapeutic targets, and working at well-coordinated multidisciplinary units. The Breast Pathology Center of Madrid has more than 40 years of experience in this field, with over 60 medical professionals working with and for breast pathology. More than 50,000 patients are examined each year, and over 400 new cancers are diagnosed annually. Historically, the first treatment which changed the course of the disease was Halsted’s radical mastectomy [1], in the late nineteenth century. Many subsequent advances took place, but what really marked a turning point was the idea that a systematic study with mammography, at highest risk ages, could detect and, therefore, change the evolution of breast cancer in population groups. Imaging techniques have experienced a highly significant development in recent years. The morphological image, of great value, has evolved into a physiological and functional image, capable of providing additional information, very valuable to better understand disease processes. Many technological changes have been established since the development of the first analogue mammography device in the sixties, with which we started working but, undoubtedly, the most important advance has been the introduction of digital mammography. Ultrasound use increased in relevance over the years as well as its application in the remaining organs and systems, while the image improved with the first static ultrasound devices, nowadays becoming a daily practice routine. Magnetic resonance imaging (MRI) is at present an almost indispensable technique for local staging and followup of breast cancer, although many technical improvements have been
Distribución altitudinal de las aves en una zona prioritaria en Sinaloa y Durango, México
Medina-Macías, Ma Nelle;González-Bernal, Marco Antonio;Navarro-Sigüenza, Adolfo G.;
Revista mexicana de biodiversidad , 2010,
Abstract: we document patterns of species richness and endemism in an elevational gradient (300 to 2 800 m) located in the espinazo del diablo region (states of durango and sinaloa), as well as its significance for the conservation of the avifauna, that is a global priority due to the presence of endemic and highly endangered taxa. we recorded a total of 209 species of birds in the fieldwork, and adding the records from literature and collections, the list increases to 229 bird species in the area. the 3 methods used for recognizing faunistic assemblages along the elevational gradient -phenetic similarity analysis, faunal congruence curves, and twinspan- recognized 3 altitudinal associations, 1 in the lowlands and 2 in the higher elevations, what represents a clear division of the avifauna. the area is a conservation priority in mexico, because is the northernmost relict of cloud forest in mesoamerica, and holds an extraordinary combination of species richness, endemism, and presence of endangered taxa.
Distribución altitudinal de las aves en una zona prioritaria en Sinaloa y Durango, México Altitudinal distribution of birds in a priority area in Sinaloa-Durango, Mexico
Ma Nelle Medina-Macías,Marco Antonio González-Bernal,Adolfo G. Navarro-Sigüenza
Revista mexicana de biodiversidad , 2010,
Abstract: En este estudio se documentan los patrones de riqueza de especies y endemismo con respecto a un gradiente altitudinal (300-2 800 m snm) en la región del Espinazo del Diablo (estados de Durango y Sinaloa). Se registró un total de 209 especies de aves, que aunadas a los registros previos en literatura y colecciones conforman una lista regional de 229 especies. Los 3 métodos empleados para reconocer la existencia de asociaciones faunísticas a lo largo del gradiente - el fenograma de similitud, las curvas de atenuación y el análisis de TWINSPAN-, coincidieron en la existencia de 3 pisos altitudinales, por lo que se observa claramente que existe una división de la avifauna en el transecto. La zona reviste una gran importancia para la conservación de los recursos biológicos de México, pues además de contener el reducto de bosque montano húmedo más norte o del oeste de Mesoamérica, la avifauna también resulta importante tanto por su riqueza específica como por el endemismo y presencia de especies de especial interés. We document patterns of species richness and endemism in an elevational gradient (300 to 2 800 m) located in the Espinazo del Diablo region (states of Durango and Sinaloa), as well as its significance for the conservation of the avifauna, that is a global priority due to the presence of endemic and highly endangered taxa. We recorded a total of 209 species of birds in the fieldwork, and adding the records from literature and collections, the list increases to 229 bird species in the area. The 3 methods used for recognizing faunistic assemblages along the elevational gradient -phenetic similarity analysis, faunal congruence curves, and TWINSPAN- recognized 3 altitudinal associations, 1 in the lowlands and 2 in the higher elevations, what represents a clear division of the avifauna. The area is a conservation priority in Mexico, because is the northernmost relict of cloud forest in Mesoamerica, and holds an extraordinary combination of species richness, endemism, and presence of endangered taxa.
Forma o do tutor para a educa o a distancia: fundamentos epistemológicos
Edith González Bernal
Eccos Revista Científica , 2008,
Abstract: In the presence of Distance Education s emergence, that replaces in this century a different view on Latin-American education context, appears the interest in investigating the questions related to tutors′ education and its epistemological statute. Thus, this text analyses concepts of tutor and tutorage used by the Colombian model of distance education, and conceived by the Instituto Colombiano para el Fomento de la Educación Superior (ICFES). In the same way, we analyze the development of the theories that traditionally support this form of education from which we observe the pedagogical models that represent the basis of tutors′ education.
La tutoría en la Universidad Colombiana: etapas, procesos y reflexiones
Edith González Bernal
Revista Historia de la Educación Latinoamericana , 2005,
Abstract: En un mundo donde el impacto de los avances tecnológicos están generando inquietud respecto de las fronteras entre educar y formar en competencias. Una mirada histórica a los procesos de tutoría y formación del tutor se hace necesaria para prospectar la educación frente a un panorama que proclama la intención de atar a los académicos a programas de software, hardware y plataformas virtuales especializadas. La tutoría y la formación del tutor, es hoy un punto crítico, en cuanto que exige un compromiso serio y responsable frente a los nuevos paradigmas de aprendizaje y las innovaciones en la teleducación, la interacción ciberespacial, el aprendizaje vitalicio y la educación adaptiva. El trabajador de la educación, en este caso el tutor, deberá engendrar cambios radicales en las formas de socializar y compartir el conocimiento, deberá dinamizar los métodos de investigación con el fin de posibilitar en los estudiantes ser sujetos críticos que sobresalen por su competencia, integridad y justicia.
Currículo basado en competencias: una experiencia en educación universitaria
González Bernal,Manuel Ignacio;
Educación y Educadores , 2006,
Abstract: we have evaluated through this investigation how to implement the curricular reform into the faculty of social communications and journalism at la sabana university. several variables in public communications area were analyzed. this work follows the "evaluative research" design and it uses the dominant focus model, selecting the quality and descriptive type issue. the project began on august 2005, and the outside work with teachers and students was made on february 2006. this research produced interesting information for educators regarding issues such these: curriculum, competences conceptualization, teaching strategies, didactic tools and evaluation strategies; all of them are showed in this part of the whole work.
Currículo basado en competencias: una experiencia en educación universitaria Curriculum based on competences: An experience on university education
Manuel Ignacio González Bernal
Educación y Educadores , 2006,
Abstract: A través de la presente investigación se evalúa la implementación de la reforma curricular de la Facultad de Comunicación Social y Periodismo de la Universidad de La Sabana, a través del análisis de diferentes variables en el área de Comunicación Pública. El trabajo se enmarca dentro del dise o conocido como investigación evaluativo, y el enfoque aplicado es el modelo de enfoque dominante, donde se privilegió el corte cualitativo y de tipo descriptivo. El proyecto comenzó en agosto del 2005, y el trabajo de campo con profesores y alumnos se adelantó en febrero del 2006. La investigación evidencia información de interés para los educadores, acerca de temas relacionados con el currículo, la conceptualización de competencias, las estrategias de ense anza, las ayudas didácticas y las estrategias de evaluación que se muestran en esta entrega parcial del trabajo. We have evaluated through this investigation how to implement the Curricular Reform into the Faculty of Social Communications and Journalism at La Sabana University. Several variables in Public Communications Area were analyzed. This work follows the "Evaluative Research" design and it uses the Dominant Focus Model, selecting the quality and descriptive type issue. The project began on August 2005, and the outside work with teachers and students was made on February 2006. This research produced interesting information for educators regarding issues such these: curriculum, competences conceptualization, teaching strategies, didactic tools and evaluation strategies; all of them are showed in this part of the whole work.
Vector spaces on non-extendable holomorphic functions
Luis Bernal-González
Mathematics , 2014,
Abstract: In this paper, the linear structure of the family $H_e(G)$ of holomorphic functions in a domain $G$ of the complex plane that are not analytically continuable beyond the boundary of $G$ is analyzed. We prove that $H_e(G)$ contains, except for zero, a dense algebra; and, under appropriate conditions, the subfamily of $H_e(G)$ consisting of boundary-regular functions contains dense vector spaces with maximal dimension, as well as infinite dimensional closed vector spaces and large algebras. The case in which $G$ is a domain of existence in a complex Banach space is also considered. The results obtained complete or extend a number of previous ones by several authors.
Page 1 /58596
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.