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Imagen de apoyo de Ecological integrity in urban forests

Por: Camilo; Duinker Ordoñez Barona | Fecha: 01/01/2012

Ecological integrity has been an umbrella concept guiding ecosystem management for several decades. Though plenty of definitions of ecological integrity exist, the concept is best understood through related concepts, chiefly, ecosystem health, biodiversity, native species, stressors, resilience and self-maintenance. Discussions on how ecological integrity may be relevant to complex human-nature ecosystems, besides those set aside for conservation, are growing in number.In the case of urban forests, no significant effort has yet been made to address the holistic concept of ecological integrity for the urban forest system. Preliminary connections between goals such as increasing tree health, maintaining canopy cover, and reducing anthropogenic stressors and the general notion of integrity exist. However, other related concepts, such as increasing biodiversity, the planting of native species, and the full meaning of ecosystem health beyond merely tree health have not been addressed profoundly as contributors to urban forest integrity.Meanwhile, other concepts such as resilience to change and self-maintenance are not addressed explicitly. In this paper we reveal two camps of interpretation of ecological integrity for urban forests that in turn rely on a particular definition of the urban forest ecosystem and a set of urban forest values. Convergence and integration of these values is necessary to bring a constructive frame of interpretation of ecological integrity to guide urban forest management into the future.

Fuente: Biblioteca Virtual Banco de la República Tipo de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Effect of coupling excess pore pressure and soil deformation on the nonlinear response

Por: Silvana; López Caballero Montoya Noguera | Fecha: 01/01/2012

The development of excess pore pressure (pw) and consequent reduction in effective stress leads to the softening of a liquefiable soil deposit that can alter ground motions in terms of amplitude, frequency content, and duration. To assess these effects in a 1D medium to loose sand model, two analyses were made: (1) A BIOT hydraulic and mechanical computation of a saturated soil deposit and (2) a mechanical computation of a dry soil with equivalent behavior. The results regarding the profile of maximum accelerations and shear strains, the surface accelerations and their corresponding response spectra ratio are analyzed.The mean values of the normalized response spectra ratio between the wet and dry surface acceleration show a deamplification of high frequencies (i.e. f > 1.0Hz) and an amplification of low ones that tend to increase with the liquefaction zone size. Coupling of pw and soil deformation is therefore of great importance to accurately model the ground motion response. On the contrary, while peak acceleration predictions could be conservative, the amplification on the low frequencies could be largely underestimated which would be highly prejudicial for tall buildings.

Fuente: Biblioteca Virtual Banco de la República Tipo de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Democracies do not fight each other. Why?

Por: Andrés Eduardo Fernández Osorio | Fecha: 01/01/2012

This article examines the existing arguments of the Democratic Peace Theory on why democracies do not fight each other. It aims to summarize the most important aspects of the theory, and to provide adequate counterarguments.First, it explains the general implications of the theory, including its origins and explanations. Second, it explores the related critiques and controversies. Third, it identifies the theory’s practical application. Finally, it offers conclusions on how effective this theory could be during the present days.

Fuente: Biblioteca Virtual Banco de la República Tipo de contenido: Artículos

Temas:
Otros
Ciencia política

Imagen de apoyo de Molecular typing of Leishmania infantum isolates from a leishmaniasis outbreak in Madrid, Spain, 2009 to 2012

Por: Ivonne Pamela; Chicharro Llanes Acevedo | Fecha: 01/01/2012

Abstract:Leishmaniasis is endemic in south-west Europe. Recent data point to the spread and (re-)emergence of this disease in previously endemic and non-endemic European countries. A recent example is the urban community outbreak of cutaneous and visceral leishmaniasis in the south-west of Madrid autonomous community, Spain, which began on 1 July 2009. A total of 446 cases associated to this outbreak were reported up to 31 December 2012. We show molecular typing data for 73 Leishmania infantum isolates obtained from January 2008 to July 2012 from different areas of Madrid, including those affected by the outbreak.Seven different genotypes were identified by combining data from two targets: the ribosomal internal transcribed spacers (ITS)-1 and -2 and the haspb (k26) gene. The results contribute to a better understanding of the parasite population circulating in the region, and indicate that most of the outbreak-associated isolates (22/31) were infected by parasites with the same combined genotype. Additional data from 82 L. infantum isolates typed as either MON-1 or MON-24 by isoenzyme analysis indicate that far from concluding that the outbreak was caused by a ‘new’ emerging genotype, further molecular typing-based surveillance studies are required to better understand the epidemiology of leishmaniasis in the region.Resumen:La leishmaniasis es endémica en el suroeste de Europa. Datos recientes apuntan a la difusión y la (re) emergencia de esta enfermedad tanto en países europeos anteriormente endémicos como no endémicos. Un ejemplo reciente es el brote urbano de leishmaniasis cutánea y visceral en el sur- oeste de Madrid, Comunidad de Madrid, España, que comenzó el 1 de julio de 2009. Un total de 446 casos relacionados con este brote se registraron hasta el 31 de diciembre de 2012. Se muestran los datos de tipificación molecular de 73 aislados de Leishmania infantum obtenidos de enero de 2008 a julio de 2012 desde las diferentes áreas de Madrid, incluidas las afectadas por el brote.Siete diferentes genotipos fueron identificados mediante la combinación de los datos de dos marcadores moleculares: los espaciadores transcritos internos (ITS) -1 y -2 y el gen (k26) haspb . Nuestros resultados contribuyen a una mejor comprensión de la población de parásitos que circula en la región, e indican que la mayoría de los aislados asociados al brote (22/31) se debían a parásitos con el mismo genotipo combinado.Adicionalmente, caracterizamos 82 aislados de L. infantum tipados como MON -1 o MON- 24 mediante el análisis de isoenzimas, y los datos obtenidos a partir de este segundo conjunto de cepas indican que el brote no fue causado por un genotipo emergente o "nuevo", sin embargo se requieren de estudios de vigilancia en tipificación para entender mejor la epidemiología de la leishmaniasis en la región.

Fuente: Biblioteca Virtual Banco de la República Tipo de contenido: Artículos

Temas:
Otros
Medicina

Imagen de apoyo de Should they play outside? Cardiorespiratory fitness and air pollution among schoolchildren in Bogotá = ¿Deberían los niños jugar al aire libre? Acondicionamiento cardiorespiratorio y contaminación del aire en Bogotá

Por: Néstor Yezid; Arango Rojas Roa | Fecha: 01/01/2012

Objective This study was aimed at comparing cardiorespiratory fitness (CF), measured as VO2 max, amongst school children exposed to varying levels of particulate matter (PM10), and air pollution in Bogotá, Colombia.Methods This was a cross-sectional study; it involved 1,045 children aged 7-12 attending four public schools served by different public transit routes and systems. Three schools were classified as being highly polluted (HP) and one slightly polluted (SP). The children and their parents were surveyed to collect data regarding their socio-demographic characteristics, physical activity habits and respiratory disease background. Objective measurements of weight and height were used to calculate the body mass index. VO2max was estimated using the 20-meter shuttle-run test, previously validated for Bogotá. Spirometry was performed on 435 children.Results After adjustment for covariates, no difference was found inVO2max between children attending SP or HP schools (girls SP 45.8 ml/kg/min vs HP 44.6 ml/kg/min, p=0.11;boys SP 47.2 ml/kg/min cf HP 48.2 ml/kg/min, p=0.41).Conclusions VO2max levels did not differ amongst children attending schools exposed to high compared to low levels of air pollution and PM. A longitudinal study assessing children’s VO2max levels in relation to exposure to highly-polluted areas is warranted.

Fuente: Biblioteca Virtual Banco de la República Tipo de contenido: Artículos

Temas:
Otros
Medicina

Imagen de apoyo de Bogotá, my digital city

Por: Juana Marcela Leal Simbaqueba | Fecha: 01/01/2012

According to the last census on 2005, Bogotá has a population of 7.363.782 inhabitants which makes it the sixth biggest city in Latin America and produces the 26% of the Colombian GDP, ranking on the tenth place, over cities as Caracas, Lima and Medellin. In 2010 occupied the 8th position on the ranking of the best cities for doing bussines in Latin America. In the last two decades Bogota has suffered several urban transformations, which largely have been influenced by the change of perspective with the arrival of visionary mayors as Enrique Peñalosa2 and Antanas Mockus. This drastic renovation on the city, had severe repercution even in the international context, with awards as the “Leone d’oro” as the best city in the Biennale di Venezia 2006, the Stockholm Challenge 2000 for the “car free day” and “Latin American Digital cities award” in 2004. However the positivism that at some point invaded Bogota citizens now its been seriously affected by the lack of continuity and evolution on the city programs, just 32% of the population considers that things on the city are on a good track3, furthermore the city has been hit by a public administration crisis by corruption cases. The role of digitalization in cities, for the flexibility of its tools and applications could determine a deffinitive step forward in developed countries, according to Paolo Fusero; “In the future while differences between rich and poor territories will become less significant, a new distinction will emerge between intelligent territories and those which do not have such aptitudes. An intelligent territory can apply adequate comunication techonologies within its perimeter in order to maximise efficiency.” (Fustero, 2008) Therefore the objective of this paper is to identify the strategy that the City of Bogota has adopted in order to implement its digitalization, but giving special importance on the iniciatives designed in order to extend its benefits to the most disadvantaged.

Fuente: Biblioteca Virtual Banco de la República Tipo de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Camacho Roldán como economista empírico

Por: Miguel Urrutia Montoya | Fecha: 01/01/2012

El trabajo describe la faceta de economista empírico de Salvador Camacho Roldán, un pensador, escritor, empresario y político del siglo XIX en Colombia. Se identifica su aporte como fuente para la historia económica cuantitativa de Colombia, y sus recomendaciones para lograr el desarrollo de su país. A esto se agrega una corta biografía para relacionar al personaje con su pensamiento.Tomado de la presentación de este documento.

Fuente: Biblioteca Virtual Banco de la República Tipo de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Law and Economics of the Jurisprudence about the Financial Sector. A Methodological Proposal = El Análisis Económico del Derecho (Law and Economics) de la Jurisprudencia sobre el Sector Financiero. Propuesta Metodológica

Por: Antonio José Núñez Trujillo | Fecha: 01/01/2012

Propuesta de una metodología para determinar si la jurisprudencia constitucional colombiana (particularmente la de la Corte Constitucional en casos de inexequibilidad) es eficiente y/o equitativa, con base en un análisis de costo-beneficio en su modalidad de ponderación de derechos, consistente en identificar los derechos en contienda, establecer sus “pesos” respectivos y compararlos.La metodología se ilustra con la revisión de dos sentencias de la Corte Constitucional, correspondientes al período de la crisis financiera de 1998-2000 (las sentencias C-700 y C-747 de 1999). En estos dos casos la conclusion de la aplicación de la metodología propuesta fue que se trata de sentencias que no fueron ni equitativas ni eficientes.

Fuente: Biblioteca Virtual Banco de la República Tipo de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Caracterización de las modalidades del patinaje artístico

Por: Pabla Vanessa Bermúdez Zea | Fecha: 01/01/2012

El Patinaje Artístico sobre ruedas está comprendido por siete modalidades, (figuras, libre, danza individual, pareja danza, pareja libre, show y precisión.) Cada una de ellas con características específicas, lo cual conlleva a que los especialistas de esta disciplina, en especial los entrenadores, conozcan a profundidad las particularidades en orden físico, técnico y psicológico de cada una de las modalidades del Patinaje Artístico, para así orientar el proceso de entrenamiento.El Patinaje Artístico sobre ruedas está comprendido por siete modalidades, (figuras, libre, danza individual, pareja danza, pareja libre, show y precisión.) Cada una de ellas con características específicas, lo cual conlleva a que los especialistas de esta disciplina, en especial los entrenadores, conozcan a profundidad las particularidades en orden físico, técnico y psicológico de cada una de las modalidades del Patinaje Artístico, para así orientar el proceso de entrenamiento.

Fuente: Biblioteca Virtual Banco de la República Tipo de contenido: Artículos

Temas:
Otros

Imagen de apoyo de Protección de marcas extranjeras notorias en el acuerdo de promoción comercial entre Colombia y Estados Unidos

Por: Yuliana Salamanca Jaramillo | Fecha: 01/01/2012

Análisis sobre las disposiciones relacionadas con marcas notorias en el Tratado de Promoción Comercial entre Colombia y Estados Unidos y su aplicación en ambos países. El artículo enfatiza en la protección que Estados Unidos y Colombia le han otorgado a las marcas extranjeras que son notorias y si, a la luz de la normativa vigente en cada país, el artículo que adopta el Tratado de Promoción Comercial entre Colombia y Estados Unidos sería vinculante para las partes.

Fuente: Biblioteca Virtual Banco de la República Tipo de contenido: Artículos

Temas:
Otros