Manifestación de cambio climático - Los glaciares de Colombia

Los glaciares de la zona ecuatorial han sido catalogados como excelentes indicadores de cambio climático por su fiel respuesta ante la dinámica de la atmósfera, lo que los convierte en excelentes laboratorios para el estudio del clima actual y pasado. En Colombia existen actualmente seis masas glaciares que ocupan un área de 47,2 km2, las cuales deben considerarse como relictos de la última glaciación con una pérdida de masa en general continua desde hace siglo y medio, la cual se ha incrementado fuertemente desde hace tres décadas relacionada con rápidos cambios en el comportamiento del clima, como lo evidencian algunos análisis de datos del clima registrados desde hace dos décadas. Esta acelerada pérdida, según la comunidad científica, está asociada con el aumento térmico de la atmósfera debido a la acumulación de gases de efecto invernadero. De persistir la actual tendencia de pérdida de área glaciar de 3 a 5% anual, se considera que en tres a cuatro décadas estén extintos los glaciares en Colombia, cifras que son comparables para algunos glaciares de países vecinos

Tissue Inhibitor of Metalloproteinases-4. The road less traveled

Tissue inhibitors of metalloproteinases (TIMPs) regulate diverse processes, including extracellular matrix (ECM) remodeling, and growth factors and their receptors' activities through the inhibition of matrix metalloproteinases (MMPs). Recent evidence has shown that this family of four members (TIMP-1 to TIMP-4) can also control other important processes, such as proliferation and apoptosis, by a mechanism independent of their MMP inhibitory actions. Of these inhibitors, the most recently identified and least studied is TIMP-4. Initially cloned in human and, later, in mouse, TIMP-4 expression is restricted to heart, kidney, pancreas, colon, testes, brain and adipose tissue. This restricted expression suggests specific and different physiological functions. The present review summarizes the information available for this protein and also provides a putative structural model in order to propose potential relevant directions toward solving its function and role in diseases such as cancer

Toward an imminent extinction of Colombian glaciers?

This study documents the current state of glacier coverage in the Colombian Andes, the glacier shrinkage over the twentieth century and discusses indication of their disappearance in the coming decades. Satellite images have been used to update the glacier inventory of Colombia reflecting an overall glacier extent of about 42.4 ± 0.71 km2 in 2016 distributed in four glacierized mountain ranges. Combining these data with older inventories, we show that the current extent is 36% less than in the mid-1990s, 62% less than in the mid-twentieth century and almost 90% less than the Little Ice Age maximum extent. Focusing on Nevado Santa Isabel (Los Nevados National Park), aerial photographs from 1987 and 2005 combined with a terrestrial LiDAR survey show that the mass loss of the former ice cap, which is nowadays parceled into several small glaciers, was about −2.5 m w.e. yr−1 during the last three decades. Radar measurements performed on one of the remnant glaciers, La Conejeras glacier, show that the ice thickness is limited (about 22 m in average in 2014) and that with such a mass loss rate, the glacier should disappear in the coming years. Considering their imbalance with the current climate conditions, their limited altitudinal extent and reduced accumulation areas, and in view of temperature increase expected in future climate scenarios, most of the Colombian glaciers will likely disappear in the coming decades. Only the largest ones located on the highest summits will probably persist until the second half of the twenty-first century although very reducedThis study was conducted in the context of the project Capacity Building and Twinning for Climate Observing Systems (CATCOS) supported by the Federal Office of Meteorology and Climatology MeteoSwiss [contract no. 7F-08114.1], between the Swiss Agency for Development and Cooperation (SDC) and MeteoSwiss, by the Swiss State Secretariat for Economic Affairs (SECO). This work was also supported by SNO GLACIOCLIM; LMI GREAT ICE (IRD); Labex OSUG@2020, Investissements d’avenir: [Grant Number ANR10 LABX56]. M. Ménégoz is supported by the project VOLCADEC funded by the Spanish programme Retos (MINECO/FEDER, ref. CGL2015–70177-R).Peer ReviewedPostprint (author's final draft

Shamanism, enthogen and contemporary art

Objetivo. El presente artículo de reflexión busca relacionar las plantas enteógenas y las prácticas chamánicas con obras de artistas contemporáneos, quienes desarrollan su propuesta plástica a partir de estos conceptos. Metodología. Es importante señalar que cada vez existen más propuestas artísticas relacionadas con la búsqueda del camino espiritual a través de prácticas contemporáneas en diferentes campos académicos, en especial el de la estética. Lo urbano ancestral es un fenómeno que surge en los últimos años y se constituye como un referente de investigación. Resultados y conclusiones. Los artistas visionarios aplican sus experiencias vivenciadas al momento de compartir las medicinas ancestrales, en especial la del yagé, para realizar o plasmar sus procesos de creación. Esta acción la determinamos como un ‘detonador’ fundamental para acceder a las creaciones de diversa índole, pasando por lo tradicional de la pintura hasta las estéticas expandidas como el paisaje sonoro y las intervenciones de ciudad con el cuerpo como soporte.Objective. This reflection article seeks to relate the entheogenic plants and the shamanic practices with works of contemporary artists who develop their plastic proposal from these concepts. Methodology. It is important to note that there are more and more artistic proposals related to the search for spiritual paths based on contemporary practices in different academic fields, specially aesthetics. The urban ancestral is a phenomenon that emerges in the last years and constitutes a reference of research. Results and conclusions. Visionary artists apply their lived experiences when sharing ancestral medicines, especially yagé, to make or shape their creation processes. This action is determined as a fundamental ‘trigger’ to access the creations of diverse nature, going through the traditional of painting to the expanded aesthetic as the sound landscape and the interventions of the city with the body as support

Algunos aspectos en la transmisión del Virus de la Mancha Anillada (DRV) de la Papaya (Carica Papaya l.)

Los objetivos del presente trabajo estuvieron encaminados hacia las características de transmisión del virus de la mancha anillada de la papaya (PRV), el cual se presenta en el municipio de Santa Marta. Los síntomas característicos de la enfermedad fueron una prominente rugosidad de la lámina foliar, la cual posteriormente se transforma en una estructura filiforme; a medida que la enfermedad avanza se presentaban manchas oleaginosas en tallo y pecíolos. El virus se transmitió mecánicamente, por injerto y por inyección hipodérmica. Para determinar las malezas hospedantes se inoculó mecánicamente una serie de plantas de las cuales resultaron portadoras Cucurbita pepo, Momordica charantia y Luffa cilíndrica. De éstas la única que presentó síntomas característicos de la enfermedad fue Cucurbita pepo. El virus es transmitido por el áfido Aphis gossypii Glover, y no se encontró transmisión por nematodos del género Meloydogine

Interpretación e ideología constitucional. Una propuesta de estudio a las decisiones en México

Las decisiones judiciales transitan no solo por el binomio interpretaciónaplicación del derecho, sino de igual forma por la ideología que subyacea los operadores mismos. Dotar de sentido a las normas constitucionales,transita no solo por desentrañar, sino por asignarles un significadoideológico, jurídico y político a la norma constitucional, circunstanciaque en México recae en los ministros que integran el Pleno de la SupremaCorte de Justicia &nbsp

Adaptive multiresolution of triangular meshes based on curvature criteria

Los modelos 3D están compuestos por miles de polígonos y en ocasiones pueden obtenerse representaciones con la misma calidad visual pero con un menor número de polígonos, lo que hace que el costo computacional, de almacenamiento y de rendimiento disminuya. Este artículo propone un método para reducir el tamaño de imágenes 3D basadas en mallas triangulares, tratando de conservar la calidad visual al extraer la desviación normal promedio, una característica de forma, y simplificando la malla únicamente donde es baja.The models 3D are compound for thousands of polygons and in occasions representations can be obtained with the same visual quality but with a smaller number of polygons, that makes that the cost computational, of storage and of rendering diminishes. This article proposes a method to reduce the size of 3D images based on triangular meshes, trying to conserve the visual quality extracting the average normal deviation, a form characteristic, and only simplifying the mesh where it is low

Identification of a field isolate of Fasciola hepatica resistant to albendazole and susceptible to triclabendazole

The experiments described here were designed to characterize the status of susceptibility/resistance to albendazole (ABZ) and triclabendazole (TCBZ) of a Fasciola hepatica isolate (named CEDIVE isolate) recovered from infected sheep (Gualeguay, Argentina) and maintained under laboratory conditions. Two separate clinical efficacy experiments were performed on sheep artificially infected with the CEDIVE isolate. Experiment 1: Sheep were randomly distributed either in an untreated control group or an ABZ (7.5 mg/kg) treated group (n= 4 each). Additionally, the systemic exposure of ABZ metabolites was assessed in those ABZ-treated infected animals. In Experiment 2, an untreated control group and a TCBZ (10 mg/kg) treated group was included (n = 4 each). The fluckicidal efficacy of ABZ and TCBZ was assessed by comparison of the number of flukes recovered from untreated and treated sheep at 15 days post-treatment. The efficacy against the CEDIVE isolate of F. hepatica was 29% (ABZ) and 100% (TCBZ). The plasma drug exposure (expressed as AUC and Cmax) observed in the ABZ treated animals (Experiment 1), was in agreement with data obtained in previous studies, which indicate that the low ABZ efficacy was not related to the quality of the pharmaceutical product and/or to a low systemic availability of the active drug/metabolite. The results reported here, clearly show that the CEDIVE isolate of F. hepatica behaves as resistant to ABZ and susceptible to TCBZ.Fil: Sanabria, Rodrigo Eduardo Fabrizio. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias; Argentina;Fil: Ceballos, Laura. Universidad Nacional del Centro de la Provincia de Buenos Aires.. Facultad de Ciencias Veterinarias. Departamento de Fisiopatologia. Laboratorio de Farmacologia; Argentina;Fil: Moreno, Laura. Universidad Nacional del Centro de la Provincia de Buenos Aires.. Facultad de Ciencias Veterinarias. Departamento de Fisiopatologia. Laboratorio de Farmacologia; Argentina;Fil: Romero, Jorge Marcelo. Universidad Nacional de la Plata. Facultad de Ciencias Veterinarias; Argentina;Fil: Lanusse Carlos. Universidad Nacional del Centro de la Provincia de Buenos Aires.. Facultad de Ciencias Veterinarias. Departamento de Fisiopatologia. Laboratorio de Farmacologia; Argentina;Fil: Alvarez Luis. Universidad Nacional del Centro de la Provincia de Buenos Aires.. Facultad de Ciencias Veterinarias. Departamento de Fisiopatologia. Laboratorio de Farmacologia; Argentina

Identification of a field isolate of Fasciola hepatica resistant to albendazole and susceptible to triclabendazole

The experiments described here were designed to characterize the status of susceptibility/resistance to albendazole (ABZ) and triclabendazole (TCBZ) of a Fasciola hepatica isolate (named CEDIVE isolate) recovered from infected sheep (Gualeguay, Argentina) and maintained under laboratory conditions. Two separate clinical efficacy experiments were performed on sheep artificially infected with the CEDIVE isolate. Experiment 1: Sheep were randomly distributed either in an untreated control group or an ABZ (7.5 mg/kg) treated group (n= 4 each). Additionally, the systemic exposure of ABZ metabolites was assessed in those ABZ-treated infected animals. In Experiment 2, an untreated control group and a TCBZ (10 mg/kg) treated group was included (n = 4 each). The fluckicidal efficacy of ABZ and TCBZ was assessed by comparison of the number of flukes recovered from untreated and treated sheep at 15 days post-treatment. The efficacy against the CEDIVE isolate of F. hepatica was 29% (ABZ) and 100% (TCBZ). The plasma drug exposure (expressed as AUC and Cmax) observed in the ABZ treated animals (Experiment 1), was in agreement with data obtained in previous studies, which indicate that the low ABZ efficacy was not related to the quality of the pharmaceutical product and/or to a low systemic availability of the active drug/metabolite. The results reported here, clearly show that the CEDIVE isolate of F. hepatica behaves as resistant to ABZ and susceptible to TCBZ.Facultad de Ciencias Veterinaria

Identification of a field isolate of Fasciola hepatica resistant to albendazole and susceptible to triclabendazole

The experiments described here were designed to characterize the status of susceptibility/resistance to albendazole (ABZ) and triclabendazole (TCBZ) of a Fasciola hepatica isolate (named CEDIVE isolate) recovered from infected sheep (Gualeguay, Argentina) and maintained under laboratory conditions. Two separate clinical efficacy experiments were performed on sheep artificially infected with the CEDIVE isolate. Experiment 1: Sheep were randomly distributed either in an untreated control group or an ABZ (7.5 mg/kg) treated group (n= 4 each). Additionally, the systemic exposure of ABZ metabolites was assessed in those ABZ-treated infected animals. In Experiment 2, an untreated control group and a TCBZ (10 mg/kg) treated group was included (n = 4 each). The fluckicidal efficacy of ABZ and TCBZ was assessed by comparison of the number of flukes recovered from untreated and treated sheep at 15 days post-treatment. The efficacy against the CEDIVE isolate of F. hepatica was 29% (ABZ) and 100% (TCBZ). The plasma drug exposure (expressed as AUC and Cmax) observed in the ABZ treated animals (Experiment 1), was in agreement with data obtained in previous studies, which indicate that the low ABZ efficacy was not related to the quality of the pharmaceutical product and/or to a low systemic availability of the active drug/metabolite. The results reported here, clearly show that the CEDIVE isolate of F. hepatica behaves as resistant to ABZ and susceptible to TCBZ.Facultad de Ciencias Veterinaria