4,354 research outputs found
Natural Language Generation and Fuzzy Sets : An Exploratory Study on Geographical Referring Expression Generation
This work was supported by the Spanish Ministry for Economy and Competitiveness (grant TIN2014-56633-C3-1-R) and by the European Regional Development Fund (ERDF/FEDER) and the Galician Ministry of Education (grants GRC2014/030 and CN2012/151). Alejandro Ramos-Soto is supported by the Spanish Ministry for Economy and Competitiveness (FPI Fellowship Program) under grant BES-2012-051878.Postprin
The Actions of the International Association of Charity Collaboration with the Other Branches of the Vincentian Family
Alteraciones de los patrones de 5- hidroximetilcitosina en enzimas epigenéticas en glioma
La 5-hidroximetilcitosina (5hmC) es una marca epigenética de descubrimiento reciente que surge de la oxidación de la 5-metilcitosina (5mC) catalizada por los enzimas TETs. De entre todos los tejidos, es en el Sistema Nervioso Central (SNC) donde se encuentran los niveles más elevados. Así pues, los gliomas, un grupo heterogéneo de tumores del SNC, se presentan como un buen candidato para el estudio de variaciones en los niveles de 5hmC. Previamente en el grupo de investigación, se encontraron diferencias en los niveles de metilación e hidroximetilación en varios genes entre muestras de glioma de pacientes y cerebros no tumorales. De todos ellos, el gen candidato, que codifica a un enzima metiltransferasa, mostró disminuciones en los niveles de 5hmC acompañados de un incremento de 5mC en regiones intragénicas. Con el fin de averiguar la implicación del gen candidato en gliomas, en primer lugar, se comprobó la posible asociación entre los niveles de 5mC y 5hmC intragénica y la expresión del gen candidato a través de tratamientos con la droga epigenética 5-aza- 2´-deoxicitidina y vitamina C. El tratamiento con 5-aza-2´-deoxicitidina disminuye los niveles de 5mC, eleva los de 5hmC intragénica e incrementa la expresión génica del gen candidato en un 45%, mientras que el tratamiento combinado con vitamina C la incrementa en un 85%. A continuación, se caracterizaron clones con expresión ectópica del gen candidato en una línea celular de glioma. Nuestros resultados muestran que dicha sobreexpresión provoca una disminución en la proliferación y viabilidad celular, sugiriendo un posible papel supresor tumoral del gen
Reglamento y bases para el régimen y gobierno de la Asociación de Labradores de Nava de la Asunción
Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201
Effects of moderate-level sound exposure on behavioral thresholds in chinchillas
Normal audiometric thresholds following noise exposure have generally been considered as an indication of a recovered cochlea and intact peripheral auditory system, yet recent animal work has challenged this classic assumption. Moderately noise-exposed animals have been shown to have permanent loss of synapses on inner hair cells (IHCs) and permanent damage to auditory nerve fibers (ANFs), specifically the low-spontaneous rate fibers (low-SR), despite normal electrophysiological thresholds. Loss of cochlear synapses, known as cochlear synaptopathy, disrupts auditory-nerve signaling, which may result in perceptual speech deficits in noise despite normal audiometric thresholds. Perceptual deficit studies in humans have shown evidence consistent with the idea of cochlear synaptopathy. To date, there has been no direct evidence linking cochlear synaptopathy and perceptual deficits. Our research aims to develop a cochlear synaptopathy model in chinchilla, similar to previously established mouse and guinea pig models, to provide a model in which the effects of cochlear synaptopathy on behavioral and physiological measures of low-frequency temporal coding can be explored. ^ Positive-reinforcement operant-conditioning was used to train animals to perform auditory detection behavioral tasks for four frequencies: 0.5, 1, 2, and 4 kHz. Our goal was to evaluate the detection abilities of chinchillas for tone-in-noise and sinusoidal amplitude modulated (SAM) tone behavioral tasks, which are tasks thought to rely on low-SR ANFs for encoding. Testing was performed before and after exposure to an octave-band noise exposure centered at 1 kHz for 2 hours at 98.5 dB SPL. This noise exposure produced the synaptopathy phenotype in naïve chinchillas, based on auditory-brainstem responses (ABRs), otoacoustic emissions (OAEs) and histological analyses. Threshold shift and inferred synaptopathy was determined from ABR and OAE measures in our behavioral animals. ^ Overall, we have shown that chinchillas, similar to mice and guinea pigs, can display cochlear synaptopathy phenotype following moderate-level sound exposure. This finding was seen in naïve exposed chinchillas, but our results suggest the susceptibility to noise can vary between naïve and behavioral cohorts because minimal physiological evidence for synaptopathy was observed in the behavioral group. Hearing sensitivity determined by a tone-in-quiet behavioral task on normal hearing chinchillas followed trends reported previously, and supported the lack of permanent threshold shift following moderate noise exposure. As we expected, thresholds determined in a tone-in-noise behavioral task were higher than thresholds measured in quiet. Behavioral thresholds measured in noise after moderate noise exposure did not show threshold shifts relative to pre-exposure thresholds in noise. As expected, chinchillas were more sensitive at detecting fully modulated SAM-tone signals than less modulated, with individual modulation depth thresholds falling within previously reported mammalian ranges. ^ Although we have only been able to confirm cochlear synaptopathy in pilot assays with naïve animals so far (i.e., not in the pilot behavioral animals), this project has developed an awake protocol for moderate-level noise exposure, an extension to our lab’s previous experience with high-level permanent damage noise exposure under anesthesia. Also, we successfully established chinchilla behavioral training and testing protocols on several auditory tasks, a new methodology to our laboratory, which we hope will ultimately allow us to identify changes in auditory perception resulting from moderate-level noise exposure
Comunidad de Labradores de Nava del Rey (Valladolid) : constirución y ordenanzas por que ha de regirse : Ley de 8 de Julio de 1898
Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2009-201
Robust and fast sliding-mode control for a DC-DC current-source parallel-resonant converter
Modern DC-DC resonant converters are normally built around a voltage-source series-resonant converter. This study aims to facilitate the practical use of current-source parallel-resonant converters due to their outstanding properties. To this end, this study presents a sliding-mode control scheme, which provides the following features to the closed-loop system: (i) high robustness to external disturbances and parameter variations and (ii) fast transient response during large and abrupt load changes. In addition, a design procedure for determining the values of the control parameters is presented. The theoretical contributions of this study are experimentally validated by selected tests on a laboratory prototype.Peer ReviewedPreprin
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