The training-induced changes on automatism, conduction and myocardial refractoriness are not mediated by parasympathetic postganglionic neurons activity

The purpose of this study is to test the role that parasympathetic postganglionic neurons could play on the adaptive electrophysiological changes produced by physical training on intrinsic myocardial automatism, conduction and refractoriness. Trained rabbits were submitted to aphysical training protocol on treadmill during 6 weeks. The electrophysiological study was performed in an isolated heart preparation. The investigated myocardial properties were: (a) sinus automatism, (b) atrioventricular and ventriculoatrial conduction, (c) atrial, conduction system and ventricular refractoriness. The parameters to study the refractoriness were obtained by means of extrastimulus test at four diVerent pacing cycle lengths (10% shorter than spontaneous sinus cycle length, 250, 200 and 150 ms) and (d) mean dominant frequency (DF) of the induced ventricular Wbrillation (VF), using a spectral method. The electrophysiological protocol was performed before and during continuous atropine administration (1 ¿M), in order to block cholinergic receptors. Cholinergic receptor blockade did not modify either the increase in sinus cycle length, atrioventricular conduction and refractoriness (left ventricular and atrioventricular conduction system functional refractory periods) or the decrease of DF of VF. These Wndings reveal that the myocardial electrophysiological modiWcations produced by physical training are not mediated by intrinsic cardiac parasympathetic activity.The authors thank Carmen Rams, Ana Diaz, Pilar Navarro and Cesar Avellaneda for their excellent technical assistance. This work has been supported by grants from the Spanish Ministry of Education and Science (DEP2007-73234-C03-01) and Generalitat Valenciana (PROMETEO 2010/093). 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A novel learning environment for undergraduate mathematics courses

This work presents a scaffolding design of learning objects as auxiliaries in the teaching-learning of mathematics at undergraduate level, through an electronic learning platform developed for using in formal mathematics courses. Its design is based on the results of surveying a group of mathematics teachers in the undergraduate fields of Science and Engineering in Mexico, about different aspects of their teaching practice. This survey is consistent with other national and international studies that highlight a series of problems found in the undergraduate fields of Science and Engineering. Guidelines for the development of this kind of  learning objects were established, which leads to curricular changes that will result in an adequate process of integrating the use of technology in the classroom. An important feature of these objects is flexibility as they are helpful tools in the innovative design process. A grounded model for the creation of teaching materials is proposed, including elements that facilitate their use, and thus, it is concluded that the use of these tools is a factor that can help alleviate some of the learning problems currently present in undergraduate level mathematics courses.&nbsp

Stroop Color-Word Interference Test: Normative data for Spanish-speaking pediatric population

OBJECTIVE: To generate normative data for the Stroop Word-Color Interference test in Spanish-speaking pediatric populations. METHOD: The sample consisted of 4,373 healthy children from nine countries in Latin America (Chile, Cuba, Ecuador, Guatemala, Honduras, Mexico, Paraguay, Peru, and Puerto Rico) and Spain. Each participant was administered the Stroop Word-Color Interference test as part of a larger neuropsychological battery. The Stroop Word, Stroop Color, Stroop Word-Color, and Stroop Interference scores were normed using multiple linear regressions and standard deviations of residual values. Age, age2, sex, and mean level of parental education (MLPE) were included as predictors in the analyses. RESULTS: The final multiple linear regression models showed main effects for age on all scores, except on Stroop Interference for Guatemala, such that scores increased linearly as a function of age. Age2 affected Stroop Word scores for all countries, Stroop Color scores for Ecuador, Mexico, Peru, and Spain; Stroop Word-Color scores for Ecuador, Mexico, and Paraguay; and Stroop Interference scores for Cuba, Guatemala, and Spain. MLPE affected Stroop Word scores for Chile, Mexico, and Puerto Rico; Stroop Color scores for Mexico, Puerto Rico, and Spain; Stroop Word-Color scores for Ecuador, Guatemala, Mexico, Puerto Rico and Spain; and Stroop-Interference scores for Ecuador, Mexico, and Spain. Sex affected Stroop Word scores for Spain, Stroop Color scores for Mexico, and Stroop Interference for Honduras. CONCLUSIONS: This is the largest Spanish-speaking pediatric normative study in the world, and it will allow neuropsychologists from these countries to have a more accurate approach to interpret the Stroop Word-Color Interference test in pediatric populations

Newly developed Learning and Verbal Memory Test (TAMV-I): Normative data for Spanish-speaking pediatric population

OBJECTIVE: To generate normative data for the Learning and Verbal Memory Test (TAMV-I) in Spanish-speaking pediatric populations. METHOD: The sample consisted of 4,373 healthy children from nine countries in Latin America (Chile, Cuba, Ecuador, Guatemala, Honduras, Mexico, Paraguay, Peru, and Puerto Rico) and Spain. Each participant was administered the TAMV-I as part of a larger neuropsychological battery. Free recall, memory delay and recognition scores were normed using multiple linear regressions and standard deviations of residual values. Age, age2, sex, and mean level of parental education (MLPE) were included as predictors in the analyses. RESULTS: The final multiple linear regression models indicated main effects for age on all scores, such that scores increased linearly as a function of age. Age2 had a significant effect in all countries except Cuba, and Puerto Rico for free recall score; a significant effect for memory delay score in all countries except Cuba and Puerto Rico; and a significant effect for recognition score in in all countries except Guatemala, Honduras, and Puerto Rico. Models showed an effect for MLPE in Chile (free recall), Honduras (free recall), Mexico (free recall), Puerto Rico (free recall, memory delay, and recognition), and Spain (free recall and memory delay). Sex affected free recall score for Cuba, Ecuador, Guatemala, Mexico, Paraguay, Peru, and Spain, memory delay score for all countries except Chile, Paraguay, and Puerto Rico, and recognition score for Ecuador, Mexico, Peru, and Spain, with girls scoring higher than boys. CONCLUSIONS: This is the largest Spanish-speaking pediatric normative study in the world, and it will allow neuropsychologists from these countries to have a more accurate way to interpret the TAMV-I with pediatric populations

Cuentos del Olivar

En este apasionante viaje tenemos las puertas abiertas para todo aquel que se quiera sumar, ya sea trabajando en pos de la difusión de la cultura ligada al olivo o disfrutando de lecturas como las que se recogen en este libro, que seguro les depara un sabroso disfrute y les descubre una cultura del olivar que tiene a sus espaldas varios milenios de historia. Les deseo que paladeen cada uno de estos relatos, que conforman un excelente aperitivo literario.Área de Historia del Art

Infecciones de repetición en un paciente portador de un sistema de neuromodulación tras la picadura de insecto

Technological developments in the last decade of the 20th century have led to the design of devices such as spinal cord stimulators for the management of severe and intractable pain. Complications after the implantation of the electrodes are infrequent, but some as breakage, infection and displacement have been reported. The case of a young technical agricultural engineer with a medical history of allergy to acarus is described. He developed a septic shock following the sting of an insect (Simu-lium Damnasum) on the top right limb, being admitted to intensive care for 48 hours. During his hospital stay, he had severe neuropathic pain with a poor response to conventional treatment. Three and a half years after this event, the patient was sent to the Pain Management Unit, where the first stage of an electrode implantation for a spinal cord stimulator was carried out. The system was withdrawn after six days due to a Staphylococcus Aureus infection. A series of epicutaneous test for regular substances and for those from the spinal cord stimulator components were made. The likelihood of an allergy to some component of the implantable device, responsible for an inflammatory reaction and subsequent infection of the catheter, was ruled out. It is important to point out that careful asepsis is still the best means to avoid infections. In patients with a medical history of atopia or allergic reactions, allergic tests should be considered as a measure to prevent rejections of devices.El desarrollo de la tecnología en las últimas décadas del siglo XX ha conllevado disponer de dispositivos, como los neuroestimuladores espinales, que han permitido un salto cualitativo muy importante en el tratamiento de pacientes con dolor severo y de difícil control. En general, las complicaciones que pueden surgir tras la colocación de un electrodo de estimulación de cordones posteriores son mínimas, pero se han descrito algunas de ellas, como son: el desplazamiento del electrodo, la infección y la rotura del electrodo. Presentamos el caso de un paciente joven, ingeniero técnico agrícola, con antecedente de alergia a ácaros del polvo, que presentó tras la picadura de un insecto (Simulium Dam-nosum) en miembro superior derecho, un cuadro de shock séptico, con ingreso durante 48 horas en Reanimación. Durante la hospitalización presentó dolor neuropático severo con escasa respuesta a tratamiento convencional. Tres años y medio después de la picadura del insecto, fue remitido a la Unidad del Dolor de nuestro centro, donde se procedió a primer tiempo de implante de electrodo de estimulación de cordones posteriores, que hubo de ser retirado a los seis días por una infección del electrodo por Estafilococo Aureus. El paciente fue sometido a las pruebas epicutáneas con las sustancias habituales y con las sustancias procedentes de los componentes del neuroestimulador. Se descartó la posibilidad de alergia a alguno de los componentes del sistema implantable que fuera el responsable de una reacción inflamatoria y posterior sobreinfección del catéter. Es necesario destacar que la mejor manera de evitar las infecciones es extremar las medidas de asepsia y debemos valorar la realización de las pruebas de alergia en pacientes con historia de reacciones alérgicas o atopia que aseguren no causarán rechazo del sistema

Temporal Variation in the Phytoplankton Community of Acapulco Bay, Mexico

Species composition and abundance of the phytoplankton community in Acapulco Bay, Mexico, were studied from May to December 2009. Samples were collected at 5 stations (4 coastal and one oceanic) at 3 depths (1, 5 and 10 m). Eighty-seven species were identified: 54 dinoflagellates, 32 diatoms and one silicoflagellate. The community was structured mainly by adiaphoric species, that is species adapted to both neritic and oceanic environments. Species abundance and composition varied significantly during the sampling period due to increased nutrient concentrations in the rainy season. Dinoflagellate species were more abundant during the dry season, and diatom species dominated numerically during the rainy season

Parasitofauna de peces de lagunas costeras del estado de Guerrero, México

No obstante que los parásitos representan un porcentaje muy importante de la biodiversidad global a nivel mundial, en muchas ocasiones son excluidos de estudios con este enfoque, debido principalmente a que han sido considerados durante muchos años, como simples agentes causantes de enfermedad. A partir de los datos obtenidos de varios estudios parasitológicos de peces y aves, efectuados en algunas lagunas costeras del estado de Guerrero a lo largo de varios años, se presenta un análisis global de la riqueza de la parasitofauna de peces, en estos altamente productivos y complejos sistemas acuáticos. La parasitofauna total estuvo constituida por 66 especies de parásitos metazoarios (425,980 individuos). En los peces se registraron 52 especies de helmintos (34 adultos y 18 larvas), en tanto que en las aves 23 (17 digéneos, dos cestodos, un acantocéfalo y tres nemátodos). Solo nueve especies principalmente digéneos, recuperadas de las aves en forma adulta, fueron encontradas también en los peces en forma larvaria. La parasitofauna estuvo conformada por dos grupos principales de parásitos, uno de origen marino constituido principalmente por monogéneos y digéneos autogénicos, y otro por especies dulceacuícolas alogénicas. Las comunidades de parásitos en peces, presentaron una riqueza de especies muy variable (7 a 26 especies), la cual fue relacionada con el número de lagunas examinadas para cada uno de los hospederos. De manera general, los resultados indicaron que la riqueza de la parasitofauna puede ser aún mayor a la aquí reportada, si un mayor número de hospederos y lagunas son examinados

SGreenH-IoT: Plataforma IoT para Agricultura de Precisión

En los últimos años, el uso de la tecnología en el sector agrícola ha tenido un fuerte impulso por parte de investigadores. El surgimiento del Internet de las Cosas (IoT) y su colaboración con otras tecnologías como el cómputo en la nube ha permitido procesar y analizar datos en tiempo real facilitando la toma de decisiones. En este artículo presentamos SGreenH-IoT una plataforma IoT de bajo costo y consumo energético para la monitorización de campos de cultivo e invernaderos. La plataforma la conforman una arquitectura de 4 capas, un protocolo de comunicación, el diseño de un nodo de bajo costo y consumo de energía y una aplicación web para la visualización de los datos. Los resultados obtenidos mediante experimentación muestran el funcionamiento efectivo de la plataforma para la recolección de datos y la integración con la toma de decisiones, con porcentaje de pérdidas de datos del cero porciento