101 research outputs found
BURGRAM: Una herramienta interactiva para el estudio de los algoritmos de análisis sintáctico ascendente y descendente
“Cinco minutos interaccionando con la ejecución de un algoritmo vale más que media hora de clase magistral”, esta podría ser la versión del conocidísimo “una imagen vale más que mil palabras” que ha inspirado el desarrollo del presente recurso docente. El contexto es el de la docencia en Procesadores de Lenguajes, en concreto la enseñanza de los algoritmos de análisis sintáctico ascendente y descendente. BURGRAM es una herramienta que permite la ejecución interactiva de este tipo de algoritmos. Aunque existen otras herramientas, BURGRAM cubre sus deficiencias poniendo el énfasis en la interactividad y el diseño funcional de la interfaz gráfica. Es posible ejecutar los algoritmos paso a paso o deshacer el efecto de los pasos aplicados. Se visualiza simultáneamente la tabla de análisis, los contenidos de la pila y de la entrada, así como el árbol de análisis sintáctico. El docente o el estudiante pueden elegir los elementos en los que quieren centrase haciendo que éstos ocupen la totalidad de la ventana de la aplicación. También es posible generar un informe en formato PDF, RTF o HTML de la traza del algoritmo que el alumno puede utilizar para referencias posteriores, añadiéndolo a las notas tomadas en clase o para resolver dudas en tutorías
Proper Motions of Thermal Radio Sources near HH 7-11 in the NGC 1333 Star Forming Region
Star forming regions are expected to show linear proper motions due to the
relative motion of the Sun with respect to the region. These proper motions
appear superposed to the proper motions expected in features associated with
mass ejection from the young stellar objects embedded in them. Therefore, it is
necessary to have a good knowledge of the proper motions of the region as a
whole in order to correctly interpret the motions associated with mass
ejection. In this paper we present the first direct measurement of proper
motions of the NGC 1333 star forming region. This region harbors one of the
most studied Herbig-Haro systems, HH 7-11, whose exciting source remains
unclear. Using VLA A configuration data at 3.6 cm taken over 10 years, we have
been able to measure the absolute proper motions of four thermal sources
embedded in NGC 1333. From our results we have derived the mean proper motions
of the NGC 1333 star forming region to be mu(alpha)cos(delta) = 9 +- 1 mas/yr
and mu(delta) = -10 +- 2 mas/yr. In this paper, we also discuss the possible
implications of our results in the identification of the outflow exciting
sources.Comment: Accepted by The Astronomical Journal (30 August 2008
La comunicación de la ciencia y la tecnología en Colombia. Apuntes para el debate
Divulgar bien, y con eficiencia los resultados de la ciencia es permitirle a la gente conocer sus múltiples posibilidades, tanto en la participación del progreso como en el ejercicio de la democracia.Influir en el cambio de comportamientos, respecto a la divulgación eficaz de los resultados, es tarea que debe competir a todos los universitarios e, incluso, a los gobernantes locales y nacionales. La difusión masiva con buena didáctica es una de las funciones primordiales del ejercicio político correcto.Compartir logros es propio de una cultura de valores racionales, de justicia, igualdad, desarrollo cultural, equidad. Y es a los mismos científicos, a las mismas comunidades de pares, a quienes interesa que sus realizaciones lleguen a la comprensión de sus conciudadanos, para que esos logros incidan en las políticas de Estado. La ejecución de una política de popularización de CyT es tarea inaplazable de los estados con responsabilidad social
Magnetic order and disorder in nanomagnets probed by superconducting vortices
We have studied two nanomagnet systems with strong (Co/Pd multilayers) and weak (NdCo alloy films) stray magnetic fields by probing the out-of-plane magnetic states with superconducting vortices. The hybrid samples are made of array of nanomagnets embedded in superconducting Nb thin films. The vortex motion detects relevant magnetic state features, since superconducting vortices are able to discriminate between different magnetic stray field strengths and directions. The usual matching effect between the superconducting vortex lattice and the periodic pinning array can be quenched by means of disorder magnetic potentials with strong stray fields at random. Ordered stray fields retrieve the matching effect and yield asymmetry and shift in the vortex dissipation signal. Furthermore vortices can discriminate the sizes of the nanomagnet magnetic domains, detecting magnetic domain sizes as small as 70 nm. In addition, we observe that the vortex cores play the crucial role instead of the supercurrents around the vortex.We thank Spanish MINECO grants FIS2013-45469, FIS2016-76058 (AEI/FEDER, UE), Spanish CM grant S2013/MIT-2850. IMDEA Nanociencia acknowledges support from the ‘Severo Ochoa’ Programme for Centres of Excellence in R&D (MINECO, Grant SEV-2016-0686). DG acknowledges RYC-2012-09864, S2013/MIT-3007 and ESP2015-65597-C4-3-R for financial support.Peer reviewe
Strawberry GRN forever: insights into the transcriptional regulatory network controlling strawberry fruit ripening and quality
Ripening is a critical step for the development of flavor quality in fruits. This character has significantly declined in many fleshy fruits over recent decades. This is particularly significant in strawberry (Fragaria × ananassa), where current cultivars are derived from a narrow germplasm collection. Improving fruit quality requires two important breakthroughs: 1) a precise understanding of the fruit ripening process that will allow the targeting of relevant genes, and 2) the identification of novel alleles responsible for fruit quality traits.
In our project, we aim at the identification and characterization of key transcription factors (TF) involved in fruit ripening regulation and their target genes, in order to infer the Gene Regulatory Network controlling this process. Among them, we have identified two TFs belonging to the NAC (FaRIF) and the BLH9 (FaRPL) family. Functional analyses establishing stable silencing and overexpression lines support that both TFs play a critical role in the regulation of fruit ripening and development. Furthermore, using a stage- and tissue-specific transcriptome analysis, we have identified TFs specifically expressed in the external layer of ripe receptacles of F. vesca fruits, which are involved in the regulation of wax and cuticle formation.
Finally, we have implemented the use of the genome-editing tool CRISPR/Cas9 in the cultivated strawberry, which we expect to open opportunities for engineering this species to improve traits of economic importance
Acute pancreatitis associated with scoliosis surgery: Could opioids be a determinant factor in its development?
Varias complicaciones médicas pueden ocurrir después de la cirugía de columna en la población pediátrica. Las técnicas quirúrgicas actuales han permitido un mayor grado de corrección de la escoliosis, pero al mismo tiempo se han descrito complicaciones inusuales que parecen estar asociadas y tienen una etiología multifactorial. Presentamos una serie de casos de tres pacientes pediátricos que se sometieron a cirugía de corrección de escoliosis con uso continuo de opioides a dosis tope, que durante la hospitalización y vigilancia postoperatoria desarrollaron pancreatitis aguda. La asociación entre la exposición prolongada a dosis altas de opioides y la aparición de pancreatitis en el contexto de una cirugía mayor espinal sugiere una relación potencial que justifica un mayor estudio.Various medical complications can occur after spinal surgery in the pediatric population. Current surgical techniques have allowed a greater degree of scoliosis correction, but at the same time, unusual complications have been described that seem to be associated and have a multifactorial etiology. We present a case series of three pediatric patients who underwent scoliosis correction surgery with continuous use of full-dose opioids, and during hospitalization and post-operative surveillance developed acute pancreatitis. The association between prolonged exposure to high-dose opioids and the onset of pancreatitis in the context of major surgery suggests a potential relationship that warrants further study.Instituto Roosevelt, Bogotá – Colombia
Evolutionary relationships of West Nile virus detected in mosquitoes from a migratory bird zone of Colombian Caribbean
First Colombian Multicentric Newborn Screening for Congenital Toxoplasmosis
Congenital toxoplasmosis can result in permanent sequel as blindness or neurological damage in children and it seems to be more severe in South America than in other continents. There is a lack of information about this frequency in Colombia, where no control program is established, although it is a recognized cause of potentially preventable congenital blindness. We propose the first Colombian multicentric study to determine the frequency and impact of congenital toxoplasmosis. More than 15,000 newborns in seven cities were studied. Newborns were tested at birth by doing a cord blood test for toxoplasmosis. Additionally, children from mothers with history of toxoplasmosis acquired during pregnancy were recalled for a follow-up. The program identified fifteen children otherwise undiagnosed; three of these children died as consequence of congenital toxoplasmosis. The frequency of the congenital infection varied significantly between cities, being higher in Armenia and Florencia, intermediate in Bogota, Bucaramanga and Barranquilla and very low in western cities such as Cucuta and Riohacha. For the first time a significant correlation was found between mean rainfall at the city and the incidence of this congenital infection
The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment
The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in
operation since July 2014. This paper describes the second data release from
this phase, and the fourteenth from SDSS overall (making this, Data Release
Fourteen or DR14). This release makes public data taken by SDSS-IV in its first
two years of operation (July 2014-2016). Like all previous SDSS releases, DR14
is cumulative, including the most recent reductions and calibrations of all
data taken by SDSS since the first phase began operations in 2000. New in DR14
is the first public release of data from the extended Baryon Oscillation
Spectroscopic Survey (eBOSS); the first data from the second phase of the
Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2),
including stellar parameter estimates from an innovative data driven machine
learning algorithm known as "The Cannon"; and almost twice as many data cubes
from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous
release (N = 2812 in total). This paper describes the location and format of
the publicly available data from SDSS-IV surveys. We provide references to the
important technical papers describing how these data have been taken (both
targeting and observation details) and processed for scientific use. The SDSS
website (www.sdss.org) has been updated for this release, and provides links to
data downloads, as well as tutorials and examples of data use. SDSS-IV is
planning to continue to collect astronomical data until 2020, and will be
followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14
happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov
2017 (this is the "post-print" and "post-proofs" version; minor corrections
only from v1, and most of errors found in proofs corrected
Cardiac electrical defects in progeroid mice and Hutchinson-Gilford progeria syndrome patients with nuclear lamina alterations
Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disease caused by defective prelamin A processing, leading to nuclear lamina alterations, severe cardiovascular pathology, and premature death. Prelamin A alterations also occur in physiological aging. It remains unknown how defective prelamin A processing affects the cardiac rhythm. We show age-dependent cardiac repolarization abnormalities in HGPS patients that are also present in the Zmpste24−/− mouse model of HGPS. Challenge of Zmpste24−/− mice with the β-adrenergic agonist isoproterenol did not trigger ventricular arrhythmia but caused bradycardia-related premature ventricular complexes and slow-rate polymorphic ventricular rhythms during recovery. Patch-clamping in Zmpste24−/− cardiomyocytes revealed prolonged calcium-transient duration and reduced sarcoplasmic reticulum calcium loading and release, consistent with the absence of isoproterenol-induced ventricular arrhythmia. Zmpste24−/− progeroid mice also developed severe fibrosis-unrelated bradycardia and PQ interval and QRS complex prolongation. These conduction defects were accompanied by overt mislocalization of the gap junction protein connexin43 (Cx43). Remarkably, Cx43 mislocalization was also evident in autopsied left ventricle tissue from HGPS patients, suggesting intercellular connectivity alterations at late stages of the disease. The similarities between HGPS patients and progeroid mice reported here strongly suggest that defective cardiac repolarization and cardiomyocyte connectivity are important abnormalities in the HGPS pathogenesis that increase the risk of arrhythmia and premature death
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