422 research outputs found
Urban seismic risk index for Medellín, Colombia, based on probabilistic loss and casualties estimations
Medellín is the second largest city of Colombia with more than 2 million inhabitants according to the latest census and with more than 240,000 public and private buildings. It is located on an intermediate seismic hazard area according to the seismic zonation of Colombia although no destructive earthquakes have occurred having as a consequence low seismic risk awareness among its inhabitants. Using the results of a fully probabilistic risk assessment of the city with a building by building resolution level and considering the dynamic soil response, average annual losses by sectors as well as casualties and other direct effects are obtained and aggregated at county level. Using the holistic evaluation module of the multi-hazard risk assessment CAPRA platform, EvHo, a comprehensive assessment that considered the social fragility and lack or resilience at county level is performed making use of a set of indicators with the objective of capturing the aggravating conditions of the initial physical impact. The urban seismic risk index,
USRi, is obtained at county level which is useful to communicate risk to decision-makers and stakeholders besides making easy identifying potential zones that can be problematic in terms of several dimensions of the vulnerability. This case study is an example of how a multidisciplinary research on disaster risk reduction helps to show how risk analysis can be of high relevance for decision-making processes in disaster risk management
Diagnóstico matemático de ecocardiografías pediátricas con medidas de dimensión fractal evaluadas con armonía matemática intrínseca
Background and objectivesGeometry allows the objective mathematical characterization of forms. Fractal geometry characterizes irregular objects. The left ventricle dynamical states form observed through echocardiography can be objectively evaluated through fractal dimension measures.MethodsA measurement of fractal dimension was performed using the Box-counting method of three defined objects in 28 echocardiographic images, 16 from normal children (group A) and 12 ill children (group B), in order to establish differences between health and illness from its comparison with the fractal dimensions of 2 normality prototypes and 2 disease prototypes.ResultsA new diagnostic, clinical application methodology was developed based in the “intrinsic mathematical harmony“(IMH) concept, and it was observed that the fractal dimensions of the defined objects for an abnormal echocardiogram show similarity to its fourth significant number, thus demonstrating the possibility of following up the evolution from normality towards disease. According to the performed calculations, 68.75% of the cases in group A could be better evaluated with the developed diagnostic methodology, and the ill ones could be diagnosed more effectively.ConclusionsThe pediatric echocardiography images can be objectively characterized with fractal dimension measurements, thus enabling the development of a clinical diagnostic methodology of echocardiography in children from the IMH concep
Alternativas de cultivos intercalados para el establecimiento de plantaciones de cítricos en el Piedemonte del departamento del Meta
Uno de los limitantes para la plantación de los huertos citrícolas en Colombia es el alto costo del establecimiento y el periodo improductivo en sus fases inciales. En condiciones del departamento del Meta, tomando como referencia árboles injertados en madarina, la entrada en producción después del transplante es: cuatro años para naranja, seis o más para tangelo, cinco para mandarina y dos para lima.Naranja-Naranja dulce - Citrus sinensis. P
Hybrid loss exceedance curve (HLEC) for disaster risk assessment
Taken into account that the natural hazard risk is a contingent liability and, therefore, a sovereign risk for national governments, it is important to assess properly the potential losses to design a suitable risk reduction, retention and transfer strategy. In this article, a disaster risk assessment methodology is proposed based on two approaches: on the one hand, the empiric estimation of losses, using information available from local disaster databases, allowing estimating losses due to small-scale events and, on the other hand, probabilistic evaluations to estimate losses for greater or even catastrophic events, for which information usually is not available due to the lack of historical data. A ‘‘hybrid’’ loss exceedance curve is thus determined, which combines the results of these two approaches and represents the disaster risk in a proper and complete way. This curve merges two components: the corresponding to small and moderate losses, calculated using an inductive and retrospective analysis, and the corresponding to extreme losses, calculated using a deductive and prospective analysis. Applications of this risk assessment technique are given in this article for eleven countries
Procedimiento para deshidratación de orégano utilizando gas propano como combustible
The article describes two important issues, the first is the process to design, implement and validate a mechanical dryer of oregano, using propane gas as fuel, and the second is the cost of the process of dehydrated, taking into account the cost of electric energy consumption by the fan and the cost of propane gas consumption by the heat exchanger. To achieve this, it was necessary review the state of the art and the study of the raw material (oregano), were established as premises of design the necessary technical specifications and the variables involved in the process, using conceptual methods and simulation to ensure that it complies with the ISO standard 7925:1999, which defines the requirements for the marketing of dried oregano and processed. Emphasis was made on the percentage of moisture that is 10%, the moisture of the product was found by the azeotropic distillation method, subsequently was validated the functionality and efficiency, comparing the results from an experimental design, then it was obtained the drying curve of oregano with the prototype of drying and it was checked if it meets ISO 7925:1999 standard and the NTC 4423 standard in order to obtain a final product dehydrated with the percentage of humidity appropriate.El artículo describe dos asuntos importantes, el primero es el proceso para diseñar, implementar y validar un secador mecánico de orégano, utilizando gas propano como combustible y el segundo es el costo del proceso de deshidratado, teniendo en cuenta el costo del consumo de energía eléctrica por el ventilador y el costo del consumo de gas propano por el intercambiador de calor. Para lograrlo se partió del estado del arte y del estudio de la materia prima (orégano), se establecieron como premisas de diseño las especificaciones técnicas necesarias y las variables que intervienen en el proceso, utilizando métodos conceptuales y de simulación para garantizar que se cumpla con la norma ISO 7925:1999 en la que se definen los requisitos para la comercialización del orégano seco y procesado, se hizo énfasis en el porcentaje de humedad que es el 10%. El porcentaje de humedad del producto se halló por el método de destilación azeotrópica, posteriormente se validó la funcionalidad y eficiencia, confrontando los resultados a partir de un diseño experimental, luego se obtuvo la curva de secado del orégano con el prototipo de secado y a partir de esta se verificó si cumple la norma ISO 7925:1999 y la norma NTC 4423 con el fin de obtener un producto final deshidratado con el porcentaje de humedad adecuado
Millennial-scale vegetation changes in the tropical Andes using ecological grouping and ordination methods
We compare eight pollen records reflecting climatic and environmental change from northern and southern sites in the tropical Andes. Our analysis focuses on the last 30ĝ€ 000 years, with particular emphasis on the Pleistocene to Holocene transition. We explore ecological grouping and downcore ordination results as two approaches for extracting environmental variability from pollen records. We also use the records of aquatic and shoreline vegetation as markers for lake level fluctuations and moisture availability. Our analysis focuses on the signature of millennial-scale climate variability in the tropical Andes, in particular Heinrich stadials (HS) and Greenland interstadials (GI). The pollen records show an overall warming trend during the Pleistocene-Holocene transition, but the onset of post-glacial warming differs in timing among records. We identify rapid responses of the tropical vegetation to millennial-scale climate variability. The signatures of HS and the Younger Dryas are generally recorded as downslope upper forest line (UFL) migrations in our transect, and are likely linked to air temperature cooling. The GI1 signal is overall comparable between northern and southern records and indicates upslope UFL migrations and warming in the tropical Andes. Our marker for lake level changes indicated a north-To-south difference that could be related to moisture availability. The air temperature signature recorded by the Andean vegetation was consistent with millennial-scale cryosphere and sea surface temperature changes but suggests a potential difference between the magnitude of temperature change in the ocean and the atmosphere. We also show that arboreal pollen percentage (AP %) and detrended correspondence analysis (DCA) scores are two complementary approaches to extract environmental variability from pollen records
Procesamiento del grano de maíz sobre la cinética de degradación de la materia seca in vitro
RESUMENObjetivo. Determinar el efecto del procesamiento del grano de maíz sobre la cinética de degradación y fermentación de la materia seca in vitro. Materiales y métodos. Se evaluaron cinco tratamientos, cada uno constó de una mezcla con dos especies, 70% pasto Kikuyo (Pennisetum clandestinum) y 30% grano de maíz (Zea mays). El grano fue sometido a diferentes procesamientos: maíz grueso seco (MGS), maíz fino seco (MFS), maíz reconstituido (MGH), reconstituido y ensilado (MGE) y ensilado con urea (MGEU). Se realizó la técnica de gas in vitro para medir parámetros de degradación y de producción de gas en diferentes horarios hasta las 48 h. Se utilizaron los modelos de Gompertz y Ørskov y McDonald para ajustar las curvas de producción de gas y degradación de MS y se evaluaron con PROC NLIN de SAS. Resultados. Los mayores volúmenes acumulados fueron obtenidos con los tratamientos MFS y MGEU con 552.5 ml y 524.03 ml, respectivamente y fueron diferentes al tratamiento MGS (p<0.05). El potencial de degradación (A+B) en MGS mostró el menor valor, siendo diferente (p<0.05) a los tratamientos MFS, MGE y MGEU. Conclusiones. El tipo de procesamiento del grano de máiz molido fino, reconstituido, ensilado con y sin urea mejoraron significativamente los parámetros de fermentación y degradación de la MS. El uso de grano molido fino (2 mm) puede ser reemplazado por grano grueso reconstituido y ensilado, el cual resulta más económico que la molienda fina
Validación del método analítico para la determinación de glimepirida en plasma humano por HPLC/UV con adición de estándar empleando glibenclamida como estándar interno
A method for detection and quantification of Glimepiride in human plasma has been developed using anisocratic elution on reversed phase liquid chromatography with ultraviolet detection at a single wavelength(231 nm) and the addition standard method. Glibenclamide was used as an internal standard. This methodinvolves a liquid-liquid drug extraction (Glimepiride and Glibenclamide) from plasma using dichloromethanediethylether (30:70%v/v). Separation was achieved on a C18 reversed phase column and the mobile phaseconsisted of 45% acetonitrile and 55% water (adjusted to pH 3.3±0.1 with acetic acid glacial). The assayhas been validated over a concentration range of 0.001 to 1.0 μg/mL with addition of Glimepiride 0.25μg/mL. Calibration curve was linear in the described concentration range. The reproducibility, stabilityand recovery of the method were evaluated. Determination of Glimepiride in human plasma by HPLC/UV method was accurate and precise with a quantitation limit of 0.2025 μg/mL. The method wassufficiently sensitive for pharmacokinetic studies of Glimepiride in human plasma.Se desarrolló un método para la detección y cuantificación de Glimepirida en plasma humano, conelución isocrática por cromatografía líquida de fase reversa, con detección ultravioleta a 231 nm,empleando el método de adición de estándar. Se utilizó Glibenclamida como estándar interno. Estemétodo involucra una extracción líquida de los principios activos (Glimepirida y Glibenclamida) usandouna mezcla de diclorometano:dietiléter (30:70 v/v). La separación se realizó en una columna C18 en fasereversa y la fase móvil consistió de una mezcla de acetonitrilo:agua (45:55 v/v) ajustado a pH 3.3±0.1con ácido acético glacial. El método se validó en el rango de concentraciones de 0.001 a 1.0 μg/mL conadición de estándar de Glimepirida de 0.25 μg/mL. La curva de calibración fue lineal en el rango deconcentraciones establecido. Se evaluó la reproducibilidad, estabilidad y porcentaje de recuperación delmétodo. El método para la determinación de Glimepirida en plasma humano por HPLC/UV fue precisoy exacto, con un límite de cuantificación de 0.2025 μg/mL. Este método fue suficientemente sensiblepara su aplicación en estudios farmacocinéticos de glimepirida
A "cookbook" for vulnerability research
There is a growing need to facilitate the interdisciplinary study of the relationship between the environment and human health and well-being. It is increasingly recognized that vulnerability is a key construct allowing discipline-specific research questions on these topics to be meaningfully contextualized. However, there is little consensus regarding the meaning of the concept of vulnerability or how it can best be utilized in research studies. In this perspective article, we use the metaphor of a "cookbook" to review promising trends in vulnerability research and to make this body of research accessible to a multi-disciplinary audience. Specifically, we discuss a selection of "recipes" (theoretical frameworks), "ingredients" (vulnerability domains), "cooking tools" (qualitative and quantitative methods), and approaches to "meal presentation" (communication of results) drawn from vulnerability studies published in the past 15 years. Our aim is for this short "cookbook" to serve as a jumping-off point for scholars unfamiliar with the vulnerability literature and an inspiration for scholars more familiar with this topic to develop new ways to navigate the tension between locally-specific assessments of vulnerability and attempts at standardization. Our ultimate take-home message is that the specifics theories and methods used in vulnerability research are less important than attention to what we see as the 3 'T's of transparency, triangulation, and transferability, and to efforts to make vulnerability research both "place-based" and comparable
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