24 research outputs found
Three‐Dimensional Magnetic Models of La Gomera (Canary Islands): Insights Into the Early Evolution of an Ocean Island Volcano
An aeromagnetic data set from the island of La Gomera was studied through two inverse modeling approaches that produced complementary views of the inner structure of this volcanic island: (1) a variable magnetization model that identified the main lateral magnetization contrasts and (2) a constant magnetization model that imaged the main magnetic source by assuming that it was a uniformly magnetized body. The modeling reveals intense magnetizations beneath the northern part of La Gomera, which occupy an important portion of the northern submarine edifice, correspond well with outcrops of the submarine volcano (Basal Complex), and confirm that most of the magnetic signal revealed by aeromagnetic mapping in the Canary Islands is due to the intense magnetizations of the intrusive complexes (plutonic bodies and dike complexes) emplaced during the initial stages of growth of the volcanic edifices. The consistency of our models with the results of a previous gravimetric study suggests that these intrusive complexes are denser and more magnetic than the surrounding rocks. The location of the main magnetic source reinforces the interpretation, first suggested by geological evidence, that the submarine and early subaerial growth of La Gomera started to the north of the present island. The elongated shape of these intrusive complexes with a nearly E-W strike agrees with the orientation of analogous structures on Tenerife and Gran Canaria, suggesting that the initial formation of the central islands of the Canary Archipelago was controlled by a set of regional fractures in a strike-slip tectonic framework.Spanish Ministry of Science, Innovation and Universities (Project CGL2015-63799-P) and by the Junta de Castilla y León and the European Regional Development Fund (ERD) (Project BU235P18)
Role of Metalinguistic Skills in the Processes of Reading and Writing in the Education
El ICFES a través del Programa de las Pruebas Saber Pro en su componente de Evaluación del Lenguaje, asume un enfoque orientado a la medición y evaluación de sus competencias lectoras de forma contextual, específicamente en las dimensiones del saber comprender, interpretar, analizar y producir tipos de textos según sus necesidades comunicativas y exigencias del medio cultural, social y académico. En este sentido cobra relevancia y pertinencia el desarrollo de estudios que permitan optimizar los procesos de lectura y escritura a partir de su relación funcional con el desarrollo de las habilidades metalingüísticas, que les brinden a los estudiantes la oportunidad de fortalecer sus competencias integrales del saber ser y saber hacer, en la generación y adquisición de los conocimientos. En este contexto, este artículo profundiza en la revisión de los referentes conceptuales y empíricos que argumental el papel de las habilidades metalingüísticas, orientadas a fortalecer el perfil de la competencia lectora de los futuros egresados frente a los retos que deben asumir en sus diferentes roles ocupacionales en la sociedad contemporánea.Abstract: The ICFES through Testing Program in its component Saber Pro Language Assessment assumes oriented measurement and evaluation of their reading skills contextually focus specifically on the dimensions of knowledge to understand, interpret, analyze and produce type’s texts according to their communicative needs and demands of the cultural, social and academic environment. This shows the importance and relevance of development studies to optimize the processes of reading and writing from their functional relationship to the development of metalinguistic abilities, to provide students with the opportunity to strengthen their comprehensive knowledge skills be and expertise in the generation and acquisition of knowledge. In this context, this article explores is the review of related conceptual and empirical argument that the role of metalinguistic skills, aimed at strengthening the profile of literacy skills of future graduates meet the challenges that must be assumed in different occupational roles in contemporary society
Imaging Thermal Anomalies in Hot Dry Rock Geothermal Systems from Near-Surface Geophysical Modelling
Convective hydrothermal systems have been extensively studied using electrical and electromagnetic methods given the strong correlation between low conductivity anomalies associated with hydrothermal brines and high temperature areas. However, studies addressing the application of similar geophysical methods to hot dry rock geothermal systems are very limited in the literature. The Timanfaya volcanic area, located on Lanzarote Island (Canary Islands), comprises one of these hot dry rock systems, where ground temperatures ranging from 250 to 605 ◦C have been recorded in pyroclastic deposits at shallow (<70m) depths. With the aim of characterizing the geophysical signature of the high ground temperature areas, three different geophysical techniques (ground penetrating radar, electromagnetic induction and magnetic prospecting) were applied in a well-known geothermal area located inside Timanfaya National Park. The area with the highest ground temperatures was correlated with the location that exhibited strong ground penetrating radar reflections, high resistivity values and low magnetic anomalies. Moreover, the high ground temperature imaging results depicted a shallow, bowl-shaped body that narrowed and deepened vertically to a depth greater than 45 m. The ground penetrating radar survey was repeated three years later and exhibited subtle variations of the signal reflection patterns, or signatures, suggesting a certain temporal variation of the ground temperature. By identifying similar areas with the same geophysical signature, up to four additional geothermal areas were revealed. We conclude that the combined use of ground penetrating radar, electromagnetic induction and magnetic methods constitutes a valuable tool to locate and study both the geometry at depth and seasonal variability of geothermal areas associated with hot dry rock systems
DOCument Scraping for Student Research: From Documents to Knowledge
Laboratorio de enseñanza-aprendizaje-proinvestigación para incentivar la vocación investigadora mediante la inmersión en procesos de extracción de datos (scraping), fomento de capacidades transversales y métodos de la investigación científica, en el ámbito de las Ciencias de la Documentació
Canagliflozin and renal outcomes in type 2 diabetes and nephropathy
BACKGROUND Type 2 diabetes mellitus is the leading cause of kidney failure worldwide, but few effective long-term treatments are available. In cardiovascular trials of inhibitors of sodium–glucose cotransporter 2 (SGLT2), exploratory results have suggested that such drugs may improve renal outcomes in patients with type 2 diabetes. METHODS In this double-blind, randomized trial, we assigned patients with type 2 diabetes and albuminuric chronic kidney disease to receive canagliflozin, an oral SGLT2 inhibitor, at a dose of 100 mg daily or placebo. All the patients had an estimated glomerular filtration rate (GFR) of 30 to <90 ml per minute per 1.73 m2 of body-surface area and albuminuria (ratio of albumin [mg] to creatinine [g], >300 to 5000) and were treated with renin–angiotensin system blockade. The primary outcome was a composite of end-stage kidney disease (dialysis, transplantation, or a sustained estimated GFR of <15 ml per minute per 1.73 m2), a doubling of the serum creatinine level, or death from renal or cardiovascular causes. Prespecified secondary outcomes were tested hierarchically. RESULTS The trial was stopped early after a planned interim analysis on the recommendation of the data and safety monitoring committee. At that time, 4401 patients had undergone randomization, with a median follow-up of 2.62 years. The relative risk of the primary outcome was 30% lower in the canagliflozin group than in the placebo group, with event rates of 43.2 and 61.2 per 1000 patient-years, respectively (hazard ratio, 0.70; 95% confidence interval [CI], 0.59 to 0.82; P=0.00001). The relative risk of the renal-specific composite of end-stage kidney disease, a doubling of the creatinine level, or death from renal causes was lower by 34% (hazard ratio, 0.66; 95% CI, 0.53 to 0.81; P<0.001), and the relative risk of end-stage kidney disease was lower by 32% (hazard ratio, 0.68; 95% CI, 0.54 to 0.86; P=0.002). The canagliflozin group also had a lower risk of cardiovascular death, myocardial infarction, or stroke (hazard ratio, 0.80; 95% CI, 0.67 to 0.95; P=0.01) and hospitalization for heart failure (hazard ratio, 0.61; 95% CI, 0.47 to 0.80; P<0.001). There were no significant differences in rates of amputation or fracture. CONCLUSIONS In patients with type 2 diabetes and kidney disease, the risk of kidney failure and cardiovascular events was lower in the canagliflozin group than in the placebo group at a median follow-up of 2.62 years
New evidence about the structure and growth of ocean island volcanoes from aeromagnetic data: The case of Tenerife, Canary Islands
We present 3-D magnetic models of Tenerife based on a high-resolution aeromagnetic survey carried out in 2006. Two different inverse modeling techniques have been applied: (1) a linear method aimed at imaging lateral magnetization contacts and (2) a nonlinear method aimed at obtaining a 3-D description of deep intrusive bodies, in which a constant magnetization value characterizes the main sources. Magnetic models show that deep intrusive structures are located beneath the northern part of the island and aligned along the E-W direction. This arrangement of intrusive bodies does not support the hypothesis of a three-armed rift system that has been present since the early formation of the island. The shallow portion of the intrusive structures shows a round geometry that agrees with the previously proposed location of some of the landslide headwalls, suggesting that collapse scars have acted as preferential sites for magma upwelling. Our magnetic model probably provides the first geophysical evidence of the location of the headwall of the Icod landslide beneath the Teide-Pico Viejo complex, thus supporting the vertical collapse hypothesis for the origin of the Cañadas caldera. The largest intrusive complex is located to the northwest of Teide and Pico Viejo, revealing the presence of a very high dike density in this area. This complex probably resulted from the intrusion of magma over the span of millions of years, beginning with the early phases of basaltic shield volcanism in central Tenerife and lasting until the building of Teide and Pico Viejo stratovolcanoes.Peer reviewe
Escenarios
El ICFES a través del Programa de las Pruebas Saber Pro en su componente de Evaluación del Lenguaje, asume un enfoque orientado a la medición y evaluación de sus competencias lectoras de forma contextual, específicamente en las dimensiones del saber comprender, interpretar, analizar y producir tipos de textos según sus necesidades comunicativas y exigencias del medio cultural, social y académico. En este sentido cobra relevancia y pertinencia el desarrollo de estudios que permitan optimizar los procesos de lectura y escritura a partir de su relación funcional con el desarrollo de las habilidades metalingüísticas, que les brinden a los estudiantes la oportunidad de fortalecer sus competencias integrales del saber ser y saber hacer, en la generación y adquisición de los conocimientos. En este contexto, este artículo profundiza en la revisión de los referentes conceptuales y empíricos que argumental el papel de las habilidades metalingüísticas, orientadas a fortalecer el perfil de la competencia lectora de los futuros egresados frente a los retos que deben asumir en sus diferentes roles ocupacionales en la sociedad contemporáneaThe ICFES through Testing Program in its component Saber Pro Language Assessment assumes oriented measurement and evaluation of their reading skills contextually focus specifically on the dimensions of knowledge to understand, interpret, analyze and produce type’s texts according to their communicative needs and demands of the cultural, social and academic environment. This shows the importance and relevance of development studies to optimize the processes of reading and writing from their functional relationship to the development of metalinguistic abilities, to provide students with the opportunity to strengthen their comprehensive knowledge skills be and expertise in the generation and acquisition of knowledge. In this context, this article explores is the review of related conceptual and empirical argument that the role of metalinguistic skills, aimed at strengthening the profile of literacy skills of future graduates meet the challenges that must be assumed in different occupational roles in contemporary society
Papel de las habilidades metalingüísticas en los procesos de lectura y escritura en la educación superior
The ICFES through Testing Program in its component Saber Pro Language Assessment assumes oriented measurement and
evaluation of their reading skills contextually focus specifically on the dimensions of knowledge to understand, interpret,
analyze and produce type's texts according to their communicative needs and demands of the cultural, social and academic
environment. This shows the importance and relevance of development studies to optimize the processes of reading and
writing from their functional relationship to the development of metalinguistic abilities, to provide students with the
opportunity to strengthen their comprehensive knowledge skills be and expertise in the generation and acquisition of
knowledge. In this context, this article explores is the review of related conceptual and empirical argument that the role of
metalinguistic skills, aimed at strengthening the profile of literacy skills of future graduates meet the challenges that must
be assumed in different occupational roles in contemporary society.El ICFES a través del Programa de las Pruebas Saber Pro en su componente de Evaluación del Lenguaje, asume un enfoque
orientado a la medición y evaluación de sus competencias lectoras de forma contextual, específicamente en las dimensiones
del saber comprender, interpretar, analizar y producir tipos de textos según sus necesidades comunicativas y exigencias del
medio cultural, social y académico. En este sentido cobra relevancia y pertinencia el desarrollo de estudios que permitan
optimizar los procesos de lectura y escritura a partir de su relación funcional con el desarrollo de las habilidades metalingüísticas,
que les brinden a los estudiantes la oportunidad de fortalecer sus competencias integrales del saber ser y saber
hacer, en la generación y adquisición de los conocimientos. En este contexto, este artículo profundiza en la revisión de los
referentes conceptuales y empíricos que argumental el papel de las habilidades metalingüísticas, orientadas a fortalecer el
perfil de la competencia lectora de los futuros egresados frente a los retos que deben asumir en sus diferentes roles ocupacionales
en la sociedad contemporánea
Strain Pattern and Kinematics of the Canary Islands from GNSS Time Series Analysis
Following the 2004 seismic unrest at Tenerife and the 2011-2012 submarine eruption at El Hierro, the number of GNSS observation sites in the Canary Islands (Spain) has increased, offering scientists a useful tool with which to infer the kinematics and present-day surface deformation of the Canary sector of the Atlantic Ocean. We take advantage of the common mode component filtering technique to improve the signal-to-noise ratio of the velocities retrieved from the daily solutions of 18 permanent GNSS stations distributed in the Canaries. The analysis of GNSS time series spanning the period 2011-2017 enabled us to characterize major regions of deformation along the archipelago through the mapping of the 2D infinitesimal strain field. By applying the triangular segmentation approach to GNSS velocities, we unveil a variable kinematic behaviour within the islands. The retrieved extension pattern shows areas of maximum deformation west of Tenerife, Gran Canaria and Fuerteventura. For the submarine main seismogenic fault between Tenerife and Gran Canaria, we simulated the horizontal deformation and strain due to one of the strongest (mbLg 5.2) earthquakes of the region. The seismic areas between islands, mainly offshore Tenerife and Gran Canaria, seem mainly influenced by the regional tectonic stress, not the local volcanic activity. In addition, the analysis of the maximum shear strain confirms that the regional stress field influences the E-W and NE-SW tectonic lineaments, which in accordance with the extensional and compressional tectonic regimes identified, might favour episodes of volcanism in the Canary Islands.Project CGL2015-63799-PPeer reviewe
Features of the deep structure of some volcanic islands of the Canary Archipelago from the passive seismo-prospecting method
Trabajo presentado en el 26º UGG General Assembly, celebrado en Praga (República Checa) del 22 de junio al 2 de julio.The Microseismic Sounding Method (MSM) [Gorbatikov, etc., 2008,2011,2013] belongs to group of passive methods of seismic prospecting and can be applied at the solution of geologic-geophysical and structural problems to various classes of geological objects, and considering various geographical and climatic conditions. The model of formation of a microseismic field in MSM doesn't proceed from the obligatory horizontal lamination of the medium. In this regard, it is considered that the main contribution to a microseismic field is provided by fundamental Rayleigh modes, and the existence of the highest modes is minimum. Informative parameter (a useful signal) in MSM is extent of distortion of initial amplitude field of microseisms due to interaction with velocity inclusions. The phase information is not used. The form and depth of the heterogeneity is estimated through the distribution of the distortions of the initial field at the surface, and the frequency at which these distortions are manifested as well. The MSM method was applied to estimate the models of the deep structure of several islands of the Canary Archipelago: El Hierro, Lanzarote and Gran Canaria. The respective velocity models obtained were then compared in independent studies: 1) with distribution of micro-seismicity and inversion of the gravity field at El Hierro Island, 2) with inversions of gravity and magnetic fields, and with morphological and structural maps at Lanzarote and Gran Canaria islands. A good correlation with the results of various methods has been found.Peer Reviewe