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Los sistemas cognitivos artificiales en la ense？anza de la matemática
Toro-Carvajal,Luis Alberto; Ortíz-Alvarez,Hugo Hernán; Jiménez-García,Francy Nelly; Agudelo-Calle,Jairo de Jesús;
Educación y Educadores , 2012,
Abstract: the use of artificial cognitive systems (acs) in processes for teaching-learning mathematics is proposed in this article. the theoretical justification for that implementation is based on a view of mathematics and the teaching mathematics as sciences and the cognitive sciences, from which the so-called computational representational model of mathematics (mcrmath) has emerged. this model of mathematics shows why mathematics teaching and learning can and should be mediated by artificial cognitive systems, which are to be understood as tools for cognitive reorganization. an understanding of the knowledge produced through the use of tools provided by artificial cognitive systems is important to the teaching mathematics. the software licensed as matlab and mathcad was used in the examples presented in this study.
Cáncer de cuello uterino: experiencia durante un período de seis a？os en un hospital universitario colombiano
García-Soto,Germán; Pachón-Rincón,Juan de Jesús; Smith Meneses-Cubides,Ronald; Zuleta-Tobón,John Jairo;
Revista Colombiana de Obstetricia y Ginecología , 2007,
Abstract: objective: the research was aimed at describing the health and socio-demographic characteristics of patients suffering from invasive cervical cancer who were attended at the san vicente de paul teaching hospital (svpth) in medellin, colombia, from 1997 to 2002. study design: this was a retrospective cohort study. population: every female patient attending svpth having a confirmed diagnosis of invasive cervical cancer 1997-2002 was included in the study. results: a total of 735 patients from 11 colombian departments (mainly antioquia, chocó and córdoba) were attended. 20.6% of these patients had a low educational level, most coming from poor areas. 24.5% had never sought having a pap smear and only 20% had been diagnosed in stage i. the disease presented clinical behaviour similar to that described in previous studies. conclusions: a high level of poverty, low educational level, limited pap smear application and predominance of the disease’s late stages was noticed in the cohort of patients being studied. although svpth is a teaching hospital attending poor people, this scenario should call attention to a catastrophic disease which can and must be prevented.
Cáncer de cuello uterino: experiencia durante un período de seis a os en un hospital universitario colombiano Cervical cancer: six years’ experience in a Colombian teaching hospital
Germán García-Soto,Juan de Jesús Pachón-Rincón,Ronald Smith Meneses-Cubides,John Jairo Zuleta-Tobón
Revista Colombiana de Obstetricia y Ginecología , 2007,
Abstract: Objetivo: describir las características sociodemográficas y de salud de las pacientes con cáncer invasor de cuello uterino atendidas en el Hospital Universitario San Vicente de Paúl (HUSVP) de Medellín, Colombia, durante el período 1997-2002. Población: toda la cohorte de pacientes con diagnóstico confirmado de cáncer invasor de cuello uterino durante el período 1997-2002 en el HUSVP. Dise o: cohorte retrospectiva. Resultados: se atendieron 735 pacientes provenientes de 11 departamentos de Colombia, principalmente de Antioquia, Chocó y Córdoba. El 20,6% de las pacientes no tenía ningún grado de escolaridad y la mayoría era de estratos bajos. El 24,5% de las pacientes nunca se realizó citología y solo el 20% de los casos se diagnosticó en estadio I. El comportamiento clínico de la enfermedad fue similar a lo descrito en la literatura. Conclusiones: en la cohorte de pacientes estudiada se evidenció un alto nivel de pobreza, bajos niveles de escolaridad, pobre cobertura de la citología cervicovaginal y un predominio notable de los estadios tardíos de la enfermedad. Aunque el HUSVP es un centro que atiende personas de bajos recursos, este panorama debe llamar la atención acerca de una enfermedad tan catastrófica que se puede y se debe prevenir. Objective: the research was aimed at describing the health and socio-demographic characteristics of patients suffering from invasive cervical cancer who were attended at the San Vicente de Paul teaching hospital (SVPTH) in Medellin, Colombia, from 1997 to 2002. Study design: this was a retrospective cohort study. Population: every female patient attending SVPTH having a confirmed diagnosis of invasive cervical cancer 1997-2002 was included in the study. Results: a total of 735 patients from 11 Colombian departments (mainly Antioquia, Chocó and Córdoba) were attended. 20.6% of these patients had a low educational level, most coming from poor areas. 24.5% had never sought having a Pap smear and only 20% had been diagnosed in stage I. The disease presented clinical behaviour similar to that described in previous studies. Conclusions: a high level of poverty, low educational level, limited Pap smear application and predominance of the disease’s late stages was noticed in the cohort of patients being studied. Although SVPTH is a teaching hospital attending poor people, this scenario should call attention to a catastrophic disease which can and must be prevented.
Los sistemas cognitivos artificiales en la ense anza de la matemática Os sistemas cognitivos artificiais no ensino da matemática Artificial Cognitive Systems in Teaching Mathematics
Luis Alberto Toro-Carvajal,Hugo Hernán Ortíz-Alvarez,Francy Nelly Jiménez-García,Jairo de Jesús Agudelo-Calle
Educación y Educadores , 2012,
Abstract: Este artículo presenta la implementación de los sistemas cognitivos artificiales (SCA) en los procesos de ense anza-aprendizaje de las matemáticas. La justificación teórica de tal implementación se hace desde el punto de vista de la Matemática y la Educación Matemática como ciencias y la Ciencia Cognitiva, de las cuales emerge el Modelo Computacional-Representacional de la Matemática (MCRMAT). Este modelo de las matemáticas da cuenta del porqué los procesos de ense anza-aprendizaje de las matemáticas pueden y deben ser mediados mediante los sistemas cognitivos artificiales, que deben ser entendidos como herramientas de reorganización cognitiva. La comprensión que se alcance sobre el conocimiento producido con la mediación de las herramientas proporcionadas por los sistemas cognitivos artificiales es importante para la ense anza de la matemática. En los ejemplos que se presentan en este trabajo se ha empleado software licenciado como Matlab y Mathcad. Este artigo apresenta a implementa o dos sistemas cognitivos artificiais (SCA) nos processos de ensino-aprendizagem da matemática. A justificativa teórica dessa implementa o se faz sob o ponto de vista da Matemática e da Educa o Matemática como ciências e a Ciência Cognitiva, das quais emerge o Modelo Computacional-Representacional da Matemática (MCRMAT). Esse modelo da matemática dá conta de por que os processos de ensino-aprendizagem da matemática podem e devem ser mediados pelos sistemas cognitivos artificiais, que devem ser entendidos como ferramentas de reorganiza o cognitiva. A compreens o que se atinge sobre o conhecimento produzido com a media o das ferramentas proporcionadas pelos sistemas cognitivos artificiais é importante para o ensino da matemática. Nos exemplos que se apresentam neste trabalho, empregou-se o software licenciado como Matlab e Mathcad. The use of artificial cognitive systems (ACS) in processes for teaching-learning mathematics is proposed in this article. The theoretical justification for that implementation is based on a view of mathematics and the teaching mathematics as sciences and the cognitive sciences, from which the so-called Computational Representational Model of Mathematics (MCRMATH) has emerged. This model of mathematics shows why mathematics teaching and learning can and should be mediated by artificial cognitive systems, which are to be understood as tools for cognitive reorganization. An understanding of the knowledge produced through the use of tools provided by artificial cognitive systems is important to the teaching mathematics. The software licensed as M
Creating S0s with major mergers: a 3D view
Miguel Querejeta,M. Carmen Eliche-Moral,Trinidad Tapia,Alejandro Borlaff,Glenn van de Ven,Mariya Lyubenova,Marie Martig,Jesús Falcón-Barroso,Jairo Méndez-Abreu,Jaime Zamorano,Jesús Gallego
Physics , 2015,
Abstract: A number of simulators have argued that major mergers can sometimes preserve discs (e.g. Springel & Hernquist 2005), but the possibility that they could explain the emergence of lenticular galaxies (S0s) has been generally neglected. In fact, observations of S0s reveal a strong structural coupling between their bulges and discs, which seems difficult to reconcile with the idea that they come from major mergers. However, in Querejeta et al. (2015a) we have used N-body simulations of binary mergers to show that, under favourable conditions, discs are first destroyed but soon regrow out of the leftover debris, matching observational photometric scaling relations (e.g. Laurikainen et al. 2010). Additionally, in Querejeta et al. (2015b) we have shown how the merger scenario agrees with the recent discovery that S0s and most spirals are not compatible in an angular momentum--concentration plane. This important result from CALIFA constitutes a serious objection to the idea that spirals transform into S0s mainly by fading (e.g. via ram-pressure stripping, as that would not explain the observed simultaneous change in $\lambda_\mathrm{Re}$ and concentration), but our simulations of major mergers do explain that mismatch. From such a 3D comparison we conclude that mergers must be a relevant process in the build-up of the current population of S0s.
CARACTERIZACIóN Y EVALUACIóN DE AGROECOSISTEMAS A ESCALA PREDIAL UN ESTUDIO DE CASO: CENTRO AGROPECUARIO COTOVE (SANTA Fé DE ANTIOQUIA, COLOMBIA)
De los Ríos Cardona,Juan Camilo; Gallego Zapata,Andrés Felipe; Vélez Vargas,León Darío; Agudelo Otalvaro,José Ignacio; Toro Restrepo,Luis Jairo; Lema Tapias,Alvaro de Jesús; Acevedo Arango,Luis Ignacio;
Revista Facultad Nacional de Agronomía, Medellín , 2004,
Abstract: the state, condition, and tendencies of the agrosystems (as) of the cotové farming center of the universidad nacional de colombia, sede medellín was evaluated by means of a parameterization and analysis of the various receptivity technologies (rt) and intensity technologies (it), based upon the proposed methodology of vélez and gastó (1999), in terms of the diversity in ae and the uses, management, and technological state, technostructural and hydrostructyural endowment, potential productivity and benefits to local, regional, and national society. results showed that the majority of the area of the center (60%) has high rt, that indicates the establishment of mechanized advanced agrotechnological management systems (ams), but only 15,72% of the area is managed with this sma. fully 69,3% of the area of the center, mainly under pasture for raising cattle, is managed with traditional sma. as a product of the interaction between rt and the sma employed, nine ae were identified, of which five, that represent 27,1% of the area ( 33,6 ha.), are managed with technologies adequate for the biophysical conditions and the receptivity technology (adequate it), and the other four, which represent 69,4% of the area ( 86,1 ha.) are managed with technologies that do not correspond to their rt conditions (extensive and inadequate its), that leads to a sub-utilization and/or deterioration of their biophysical and ecological conditions.
CARACTERIZACIóN Y EVALUACIóN DE AGROECOSISTEMAS A ESCALA PREDIAL. UN ESTUDIO DE CASO: CENTRO AGROPECUARIO PAYSANDú (MEDELLíN, COLOMBIA)
de los Rios Cardona,Juan Camilo; Gallego Zapata,Andrés Felipe; Vélez Vargas,León Darío; Agudelo Otalvaro,José Ignacio; Toro Restrepo,Luis Jairo; Lema Tapias,Alvaro de Jesús; Acevedo Agudelo,Luis Ignacio;
Revista Facultad Nacional de Agronomía, Medellín , 2004,
Abstract: the state, condition, and tendencies of the agro-ecosystems (ae) of the paysandú farming center of the universidad nacional de colombia, sede medellín were characterized and evaluated by means of parameterization and analysis of the various technological receptivity (rt, after the spanish initials) and technological intensity (it), based upon a methodological proposal of vélez and gastó (1999), in terms of ae diversity and of the uses, management, and technological acceptance, technostructural and hydrostructural endowment, potential productivity and services to the local, regional, and national society. the results showed that the greater part of the center (72%) has very low rt, which does not permit the establishment of mechanized advanced agrotechological management systems (sma). however, 69.8% of the area is managed with sma adequate for the restrictions imposed by the rt. sixty-two percent of the area of the center, principally under pasture cover for dairy cattle production, is managed with advanced sma. as a result of the interaction between rt and the sma employed, six ae were identified, of which three, that represent 69.8% of the area ( 100,2 ha.), are managed with technologies adequate for their biophysical conditions or with technological receptivity (adequate it), and the other three, that represent 28,57% of the area ( 43,1 ha.) are managed with technologies that do not correspond to their rt conditions (traditional it), which leads to a deterioration of their biophysical and ecological conditions.
Formation of S0 galaxies through mergers: Explaining angular momentum and concentration change from spirals to S0s
Miguel Querejeta,M. Carmen Eliche-Moral,Trinidad Tapia,Alejandro Borlaff,Glenn van de Ven,Mariya Lyubenova,Marie Martig,Jesús Falcón-Barroso,Jairo Méndez-Abreu
Physics , 2015, DOI: 10.1051/0004-6361/201526354
Abstract: The CALIFA team has recently found that the stellar angular momentum and concentration of late-type spiral galaxies are incompatible with those of lenticular galaxies (S0s), concluding that fading alone cannot satisfactorily explain the evolution from spirals into S0s. Here we explore whether major mergers can provide an alternative way to transform spirals into S0s by analysing the spiral-spiral major mergers from the GalMer database that lead to realistic, relaxed S0-like galaxies. We find that the change in stellar angular momentum and concentration can explain the differences in the $\lambda_\mathrm{Re}$--$R_{90}/R_{50}$ plane found by the CALIFA team. Major mergers thus offer a feasible explanation for the transformation of spirals into S0s.
Una aproximación a la distribución de la varianza en poblaciones simétricas no normales
Avila G. Jesús Antonio,Clavijo M. Jairo Alfonso
Revista Colombiana de Estadística , 1999,
Abstract: En este artículo se hacen algunas consideraciones acerca de la distribución del estimador de la varianza para algunas distribuciones simétricas continuas no normales, proponiendo para ello una función de densidad que permita estimar sus cuatro primeros momentos. Se comparan los resultados con la función de aproximación de Box y se utiliza el método de un sistema de ecuaciones lineales.
Stellar populations across galaxy bars in the MUSE TIMER project
Adrian Bittner,Adriana de Lorenzo-Cáceres,Bernd Husemann,Charlotte E. Donohoe-Keyes,Dimitri A. Gadotti,Facundo A. Gómez,Francesca Fragkoudi,Glenn van de Ven,Isabel Pérez,Jairo Méndez-Abreu,Jesús Falcón-Barroso,Justus Neumann,Marie Martig,Marja K. Seidel,Patricia Sánchez-Blázquez,Robert J. J. Grand,Rüdiger Pakmor,Taehyun Kim
- , 2020, DOI: 10.1051/0004-6361/202037604
Abstract: Stellar populations in barred galaxies save an imprint of the influence of the bar on the host galaxy’s evolution. We present a detailed analysis of star formation histories (SFHs) and chemical enrichment of stellar populations in nine nearby barred galaxies from the TIMER project. We used integral field observations with the MUSE instrument to derive unprecedented spatially resolved maps of stellar ages, metallicities, [Mg/Fe] abundances, and SFHs, as well as Hα as a tracer of ongoing star formation. We find a characteristic V-shaped signature in the SFH that is perpendicular to the bar major axis, which supports the scenario where intermediate-age stars (～2？？？6 Gyr) are trapped on more elongated orbits shaping a thinner part of the bar, while older stars (> 8 Gyr) are trapped on less elongated orbits shaping a rounder and thicker part of the bar. We compare our data to state-of-the-art cosmological magneto-hydrodynamical simulations of barred galaxies and show that such V-shaped SFHs arise naturally due to the dynamical influence of the bar on stellar populations with different ages and kinematic properties. Additionally, we find an excess of very young stars (< 2 Gyr) on the edges of the bars, predominantly on the leading side, thus confirming typical star formation patterns in bars. Furthermore, mass-weighted age and metallicity gradients are slightly shallower along the bar than in the disc, which is likely due to orbital mixing in the bar. Finally, we find that bars are mostly more metal-rich and less [Mg/Fe]-enhanced than the surrounding discs. We interpret this as a signature that the bar quenches star formation in the inner region of discs, usually referred to as star formation deserts. We discuss these results and their implications on two different scenarios of bar formation and evolution
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