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Imagen de apoyo de Estimating future residential water consumption in Phoenix, Arizona based on simulated changes in climate

Por: Hermes Camilo; Balling Cubaque Barrera | Fecha: 2009

Previous studies have shown that residential water consumption in Phoenix, Arizona is significantly related to changes in climate, although that sensitivity varies substantially from one census tract to another. In this investigation, we determine the empirical relationship between water consumption and variations in temperature and precipitation. We find the sensitivity of consumption to either climate variable is positively related to the percent of land covered in mesic irrigated landscaping, mean household income, lot size, and percent of single-family residential lots containing swimming pools. We use estimated changes in temperature and precipitation for 50 model – scenario combinations presented by the IPCC, and we determined that mean water consumption should increase by an average of over three percent by 2050, but the climate-induced change in consumption varies considerably across the census tracts.

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

Temas:
Otros

Imagen de apoyo de Migration, Political Art and Digitalization

Por: Sara Wiederkehr González | Fecha: 2016

Throughout this paper, the main interest is in describing the use and practice of socialnetworking by Colombian migrants and its influence on the relation with, and the construction of a discourse about, Colombian conflict and social reality. In addressing the problematization of cyberspace and its virtuality as a space, an account is given of the singularities, political concerns, and personal expectations of two Colombian migrants living in Berlin. This leads to an analysis of the influence of virtuality in the construction of political and social discourses and of practices abroad. The discussion of the authenticity and “realness” of the virtual world and virtual relationships invokes the supposed opposition between virtual space as abstract, and the real world as the tangible and real one. However the notions of virtuality and reality are not necessarily opposed. According to Augé (1995), a place is defined as relational, historical and concerned with identity. Borrmann (2013) concludes in her study that cyberspace cannot be understood as an abstract place, meant to exist only “while we are sitting in front of the computer” (64). From this reasoning, several questions guide this paper: If the cyberspace is a tangible one, how do migrants—those people who supposedly live in between territories—relate to virtuality? How are these virtual spaces and places constructed from the singularities of Colombian migrants in Berlin? How do they relate to the actuality overseas, in their home countries?

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

Temas:
Otros
Ciencias sociales

Imagen de apoyo de Constructing the tropics: Nineteenth Century British representations of Colombia

Por: Simón Uribe Martínez | Fecha: 2015

This paper considers nineteenth Century British travel accounts of Colombia. By analysing how those travellers represented the country, it aims to explore the different ways in which “the tropics” were imagined, experienced and constructed. On the one hand, it is suggested that those representations helped to forge an image of the country as a promising nature inhabited by backward races, underpinning a widespread vision of the tropic: that of a vacant space abounding of exploitable natural resources waiting to be transformed by Europeans’ ‘civilized’ hands and endeavour. On the other hand, contested and often contradictory ideas that those travellers harboured about climate and European acclimatization are explored, suggesting that Europeans’ perceptions of the tropic resulted from a permanent negotiation between images brought from home and the landscapes they encountered. To conclude, it is argued that those constructions are revealing of how travel writing was above all a cultural practice, where the traveller’s vision is not exclusively determined by established paradigms, but transformed by the landscapes he encounters and interacts with.

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

Temas:
Otros

Imagen de apoyo de Literature review : management of project oriented organisations

Por: Mario Jheinner; Aryan Bunbuarka Vargas Cubides | Fecha: 2010

This paper illustrates the analysis of an intensive research in several books and organisational theories, exemplifies the nature of various organisational structures and how those structural mechanisms affect project management. To this end, suitable organisational characteristics to develop projects are identified and classify them into cultural and structural characteristics. These implicit characteristic inside organisations allow or hinder the achievement of projects. Definitions and clarifications from practical examples of project oriented organisation are differentiated with non-project oriented organisations. There will be suggestion of what may be the most suitable scenarios which Project Managers could obtain the maximum performance to achieve the organisational goals and with this, keep evolving the industry and managing changes to attend market needs.

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

Temas:
Otros

Imagen de apoyo de Proof of concept of a stimulator based on AC current rectification for neuroprosthetics

Por: Laura Becerra Fajardo | Fecha: 2012

For several years, researchers have developed techniques to replace and enhance the capabilities of our neural system by means of implantable electrical stimulation technologies. Even though important work has been done in this field, further progress must be accomplished in terms of miniaturization in order to ensure comfort, simpler surgical implantation procedures, and the capability of using multiple wireless smart stimulators for achieving more muscle recruitment. In the past, with the objective of accomplishing an unprecedented level of miniaturization, we have proposed the development of implantable stimulators that would act as rectifiers of AC current supplied by external electrodes. Here it is described the development and evaluation of an addressable stimulator based on discrete component technology as a proof-of-concept of the proposed method. This macroscopic version of the stimulator is capable of generating magnitude controlled bipolar pulses according to commands modulated in the AC current. Multiple evaluations were done to test the device, including DC current testing, in-vitro and invivo testing, concluding that the developed system is an effective proof-of-concept of the method proposed, being able to perform controlled electrical stimulation. Electrical current testing showed that anodal and cathodal currents were generated, and in-vivo testing showed the effective electrical stimulation of an anesthetized earthworm. It is concluded that the idea of developing smart rectifiers as implantable stimulators is feasible. This represents a first step towards the design of an implantable device with a miniaturization level without precedents.

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

Temas:
Otros

Imagen de apoyo de Regulation of autophagy by Forkhead box (FOX) O transcription factors

Por: María Catalina; Vos Gómez Puerto | Fecha: 2012

Abstract: Proliferation, differentiation and apoptosis are tightly regulated by extracellular stimuli including hormones, growth factors and cytokines. A balance between these processes is a critical requirement for tissue homeostasis and loss of this balance can result in development of disease. The binding of such mediators to their cognate receptors induces activation of intracellular signal transduction cascades that, through regulation of transcription, eventually results in altered gene expression and changes in cell fate decisions. Constitutive activation of oncogenic signalling pathways by loss of tumor suppressors and activation of oncogenes causes malignant transformation, which is characterized by a differentiation block and the ability of the cancer cells to proliferate and survive independent of growth factor signals. Recently both oncogenes and tumor suppressors have been shown to be critical regulators of autophagy in response to cellular stress. In this review current data concerning a novel role for FoxO transcription factors in regulating autophagy will be discussed. Resumen: La proliferación, diferenciación y apoptosis son procesos estrictamente regulados por estímulos extracelulares que incluyen hormonas, factores de crecimiento y citoquinas. El equilibrio entre dichos procesos es crítico para la homeostasis del tejido y su perdida puede resultar en el desarrollo de enfermedades. La unión de estos mediadores a sus receptores induce la activación de cascadas intracelulares que a través de la regulación de la transcripción, se traducen en la expresión de genes alterados. La activación constitutiva de rutas de señalización oncogénicas por la pérdida de supresores tumorales y la activación de oncogenes provoca la transformación maligna, que se caracteriza por un bloqueo en la diferenciación y por la capacidad de las células cancerosas de proliferar y sobrevivir independiente de las señales del factor de crecimiento. Recientemente se ha demostrado que oncogenes y supresores tumorales son reguladores críticos de la autofagia en respuesta al estrés celular. En esta revisión bibliográfica se analiza el nuevo rol del factor de trascripción FOXO en la regulación de la autofagia.

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

Temas:
Otros
Medicina

Imagen de apoyo de Use of systemic medication in patients with oral lichen planus - a possible association with hypothyroidism

Por: Jairo; Mattsson Robledo Sierra | Fecha: 2013

Abstract: BACKGROUND: Several drugs have been regarded as a possible aetiological factor for oral lichen planus (OLP). OBJECTIVE: To investigate the medication profile of patients with OLP and its possible association with the pathogenesis of OLP. METHODS: Data from 956 patients with OLP and 1029 controls were collected using a standardized registration method. All regular medications were recorded and classified according to the Anatomical Therapeutic Chemical Classification System. RESULTS: Patients with OLP used thyroid preparations (P < 0.001) and non-steroidal anti-inflammatory drugs (NSAIDs) (P < 0.01) in higher proportions compared to controls. A multivariate logistic regression model demonstrated that levothyroxine was associated with OLP (multivariate OR 3.39, 95% CI: 2.09-5.46, P < 0.001), even after controlling for confounders, including age, sex, smoking, allergies and systemic diseases. No statistical significance could be found between NSAIDs and OLP using the same model. CONCLUSION: In this study, the use of levothyroxine was associated with OLP, which in turn suggests a possible connection with hypothyroidism." Resumen: ANTECEDENTES: Muchos medicamentos han sido considerados posibles factores etiológicos del liquen plano oral (LPO). OBJETIVO: Investigar el perfil medicamentoso de pacientes con LPO y su posible asociación con la patogénesis del LPO. METODOS: Datos de 956 pacientes con LPO y 1029 controles fueron recolectados usando un método estandarizado de registro. Todos los medicamentos fueron registrados y clasificados de acuerdo al Sistema de Clasificación Anatómica, Terapéutica, Química. RESULTADOS: Los pacientes con LPO usan preparaciones para la tiroides (P < 0.001) y antiinflamatorios no esteroideos (AINEs) (P < 0.01) en mayores proporciones comparado con los controles. Una regresión logística multivariada demostró que la levotiroxina está asociada con LPO (OR multivariado 3.39, 95% CI: 2.09-5.46, P < 0.001), aún después de controlar para factores de confusión, incluyendo edad, sexo, tabaquismo, alergias y enfermedades sistémicas. No se encontró una significancia estadística entre los AINEs y el LPO usando el mismo modelo. CONCLUSION: En este estudio, el uso de levotiroxina está asociado con el LPO, lo cual a su vez sugiere una posible conexión con el hipotiroidismo."

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

Temas:
Otros
Medicina

Imagen de apoyo de Are the New Physics Contributions from the Left-Right Symmetric Model Important for the Indirect CP Violation in the Neutral B Mesons?

Por: Yeinzon; Quimbay Rodríguez García | Fecha: 2005

Several works analyzing the new physics contributions from the LeftRight Symmetric Model to the CP violation phenomena in the neutral B mesons can be found in the literature. These works exhibit interesting and experimentally sensible deviations from the Standard Model predictions but at the expense of considering a low right scale ?R around 1 TeV. However, when we stick to the more conservative estimates for ?R which say that it must be at least 107 GeV, no experimentally sensible deviations from the Standard Model appear for indirect CP violation. This estimate for ?R arises when the generation of neutrino masses is considered. In spite of the fact that this scenario is much less interesting and says nothing new about both the CP violation phenomenon and the structure of the LeftRight Symmetric Model, this possibility must be taken into account for the sake of completeness and when considering the see-saw mechanism that provides masses to the neutrino sector.

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

Temas:
Otros

Imagen de apoyo de The Rights of Indigenous Peoples in the Light of International Human Rights Law

Por: Luisa María Villa Yepes | Fecha: 2016

In the first part of this study we are going to deal with the problem of definition of an indigenous people in order to identify the subjects of international legal protection. At a second stage it is necessary to seek possible justifications in favor of a special protection of indigenous minorities. Why shall indigenous minorities be granted a privileged status under international law?In the third part of this contribution we will focus on indigenous protection from a general human rights and anti-discrimination perspective. It has to be understood that indigenous rights are an integral part of international human rights law. However, the internal cultural and religious self-determination of indigenous peoples has to be conceived in line with the basic principles of human rights protection. Therefore, we will have to ask whether, after centuries of colonialism, human rights doctrine applies a paternalistic approach towards indigenous minorities and introduces a new kind of colonial domination.

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

Temas:
Otros
Ciencias sociales

Imagen de apoyo de Exporting Colombia’s Performing Arts = Exportación de las Artes Escénicas de Colombia

Por: Cristina; Ruiz Matos | Fecha: 2018

Colombia is known for its cultural richness and diversity reflected through the work of different performing art disciplines and expressions. There’s a solid presence and active work from cultural leaders, companies and independent groups, but their plays and productions usually have a short-term cycle performance or not enough venues for local staging. In hopes of responding to the present challenges, the objective is to export Colombian artistic groups to participate in Italian Festivals. This is a solution that provides sustainability, continuity and international reach for Colombia's performing arts offer. The work identifies Colombia’s context in its cultural offer and policies and further presents the development of an Artistic Export Plan that selects five Colombian groups for five different Italian festivals. The application work results in a document named Informative Kit that strategically presents each group for an international venue. An alliance plan is also contemplated as funding collaborations that may later cover travel expenses for the groups. This project connects different types of experiences representing the deep and functioning links between many cultural industries around the world.

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

Temas:
Otros