471 research outputs found

    El monstruo imposible

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    "Preguntarnos por la existencia de los monstruos puede parecer una cuestión infantil o cuando menos ociosa. Pero, si no existen, si nunca han existido, ¿de dónde ha surgido la idea del monstruo, cómo y por qué los hemos inventado? ¿Desde cuándo está presente esta figura en la vida del hombre? Para rastrear sus primeras apariciones en la historia, primero deberíamos tener claro qué es exactamente lo que estamos buscando. ¿Qué es un monstruo? Ésta es la primera pregunta que intentamos responder en esta investigación. Así, hemos trazado un camino que parte de la dilucidación de su etimología hasta la revelación de una de las funciones menos visibles del monstruo saciar un instinto de muerte pasando por la confrontación entre lo cómico y lo monstruoso. En el primer capítulo, entonces, intentaremos responder de forma general qué es un monstruo, cuáles son sus elementos fundamentales. En el segundo capítulo preparamos el terreno para la confrontación monstruo-risa y finalmente, en el tercer capítulo ponemos en relación la risa cómica con el monstruo y desentrañamos la contradicción que implica hablar de un monstruo cómico. Esta investigación no solo plantea qué es un monstruo sino cuál puede ser uno de los posibles mecanismos para desarticularlo "

    Coatepec en los albores del siglo XX. Fotografía de Atilano Pérez

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    Reseña del libro Coatepec en los albores del siglo XX. Fotografía de Atilano Pérez  de la autoría de Jesús Javier Bonilla Palmeros. Este volumen se conforma de una presentación y cinco partes. Incluye una serie de 97 imágenes fotográficas de estudio y eventos, así como tarjetas postales obra de Don Atilano Pérez realizadas entre 1880 y 1913. La obra también nos ofrece un panorama histórico general de la ciudad de Coatepec a través de fotografías antiguas producto de uno de los principales fotógrafos de la localidad y que hoy constituyen un importante acervo del pasado histórico del municipio

    Memoria para el Futuro. Vinculación y comunicación pública para la salvaguarda del patrimonio arqueológico

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    Este artículo presenta una estrategia de vinculación y de comunicación pública de la arqueología a fin de promover la valoración y la salvaguarda del patrimonio arqueológico entre los habitantes de la región olmeca, en el sur del estado de Veracruz, México. Tiene como meta la apropiación y la identidad cultural a través del diálogo de saberes entre los arqueólogos y la sociedad en torno a la historia reciente de piezas arqueológicas halladas de manera fortuita. Dicha propuesta se fundamenta en la relación teórica entre las perspectivas de la historia del tiempo presente y la arqueología del pasado reciente, mientras que las nociones de memoria e identidad cobran particular importancia. A través de un caso de estudio piloto en la localidad de Antonio Plaza mostramos la aplicación de dicha estrategia –su operación y primeros resultados–, que se visualiza como una vía factible para promover la valoración y la protección del patrimonio arqueológico en las comunidades participantes. Palabras clave: comunicación, vinculación, arqueología, memoria, patrimoni

    In vivo whole-cell recordings of stimulus-specific adaptation in the inferior colliculus

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    The inferior colliculus is an auditory structure where inputs from multiple lower centers converge, allowing the emergence of complex coding properties of auditory information such as stimulus-specific adaptation. Stimulus-specific adaptation is the adaptation of neuronal responses to a specific repeated stimulus, which does not entirely generalize to other new stimuli. This phenomenon provides a mechanism to emphasize saliency and potentially informative sensory inputs. Stimulus-specific adaptation has been traditionally studied analyzing the somatic spiking output. However, studies that correlate within the same inferior colliculus neurons their intrinsic properties, subthreshold responses and the level of acoustic stimulus-specific adaptation are still pending. For this, we recorded in vivo whole-cell patchclamp neurons in the mouse inferior colliculus while stimulating with current injections or the classic auditory oddball paradigm. Our data based on cases of ten neuron, suggest that although passive properties were similar, intrinsic properties differed between adapting and non-adapting neurons. Non-adapting neurons showed a sustained-regular firing pattern that corresponded to central nucleus neurons and adapting neurons at the inferior colliculus cortices showed variable firing patterns. Our current results suggest that synaptic stimulus-specific adaptation was variable and could not be used to predict the presence of spiking stimulus-specific adaptation. We also observed a small trend towards hyperpolarized membrane potentials in adapting neurons and increased synaptic inhibition with consecutive stimulus repetitions in all neurons. This finding indicates a more simple type of adaptation, potentially related to potassium conductances. Hence, these data represent a modest first step in the intracellular study of stimulusspecific adaptation in inferior colliculus neurons in vivo that will need to be expanded with pharmacological manipulations to disentangle specific ionic channels participatio

    The effect of NMDA-R antagonist, MK-801, on neuronal mismatch along the rat auditory thalamocortical pathway

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    Efficient sensory processing requires that the brain maximize its response to unexpected stimuli, while suppressing responsivity to expected events. Mismatch negativity (MMN) is an auditory event‐related potential that occurs when a regular pattern is interrupted by an event that violates the expected properties of the pattern. According to the predictive coding framework there are two mechanisms underlying the MMN: repetition suppression and prediction error. MMN has been found to be reduced in individuals with schizophrenia, an effect believed to be underpinned by glutamate N‐methyl‐d‐aspartate receptor (NMDA‐R) dysfunction. In the current study, we aimed to test how the NMDA‐R antagonist, MK‐801 in the anaesthetized rat, affected repetition suppression and prediction error processes along the auditory thalamocortical pathway. We found that low‐dose systemic administration of MK‐801 differentially affect thalamocortical responses, namely, increasing thalamic repetition suppression and cortical prediction error. Results demonstrate an enhancement of neuronal mismatch, also confirmed by large scale‐responses. Furthermore, MK‐801 produces faster and stronger dynamics of adaptation along the thalamocortical hierarchy. Clearly more research is required to understand how NMDA‐R antagonism and dosage affects processes contributing to MMN. Nonetheless, because a low dose of an NMDA‐R antagonist increased neuronal mismatch, the outcome has implications for schizophrenia treatment

    Neurons along the auditory pathway exhibit a hierarchical organization of prediction error

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    Perception is characterized by a reciprocal exchange of predictions and prediction error signals between neural regions. However, the relationship between such sensory mismatch responses and hierarchical predictive processing has not yet been demonstrated at the neuronal level in the auditory pathway. We recorded single-neuron activity from different auditory centers in anaesthetized rats and awake mice while animals were played a sequence of sounds, designed to separate the responses due to prediction error from those due to adaptation effects. Here we report that prediction error is organized hierarchically along the central auditory pathway. These prediction error signals are detectable in subcortical regions and increase as the signals move towards auditory cortex, which in turn demonstrates a large-scale mismatch potential. Finally, the predictive activity of single auditory neurons underlies automatic deviance detection at subcortical levels of processing. These results demonstrate that prediction error is a fundamental component of singly auditory neuron responses

    Anomalous origin of the left coronary artery with origin in the right coronary artery from a single coronary ostium associated with multivessel coronary artery disease: case report and literature review

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    The anomalous origin of the coronary arteries is a group of rare congenital heart conditions in which there has been an increase in its diagnosis thanks to more accessible and less invasive imaging techniques such as coronary angiotomography, which allows visualization of the arteries in its entire path in a short exploration interval, with adequate spatial and temporal resolution. The clinical presentation is variable, up to 80% are asymptomatic and the remaining 20% may present arrhythmias, myocardial infarction, heart failure and sudden death. We present the case of a patient with unstable angina in whom an anomalous origin of the left coronary artery (LCA) with origin in the right coronary artery (RCA) from a single coronary ostium associated with multivessel coronary artery disease was diagnosed

    La migración interna en el estado de veracruz y sus efectos en el diseño de políticas públicas: caso ciudad de xalapa

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    The State of Veracruz, in addition to occupying third place nationally (INEGI, 2015), has historically been an entity that expels migrants to the United States, a situation noticeable in the late 1980s and early 1990s, although it has also served as one of the main receiving entities of migrants who settle in the main urban centers such as the city of Xalapa, since being the capital of the State, it has various characteristics to serve as a point of attraction, generating effects that require measures of attention by municipal authorities on the provision of services and optimal administration of the territory. In this work, the documentary information studied is described with the purpose of supporting a research project aimed at identifying the situation of internal migration in the municipality of Xalapa, Veracruz.El Estado de Veracruz, además de ocupar el tercer lugar a nivel nacional (INEGI, 2015), ha sido históricamente una entidad expulsora de migrantes hacia los Estados Unidos, situación perceptible a finales de la década de 1980 principios de 1990, aunque también ha fungido como una de las principales entidades receptoras de migrantes los cuales se establecen en los principales centros urbanos como lo es la ciudad de Xalapa, ya que al ser la capital del Estado, posee diversas características para fungir como punto de atracción, generando efectos que requieren medidas de atención por parte de las autoridades municipales sobre la provisión de servicios y óptima administración del territorio. En este trabajo, se describe la información documental estudiada con la finalidad de fundamentar un proyecto de investigación orientado a identificar la situación de la migración interna en el municipio de Xalapa, Veracruz
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