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Humans are able to seamlessly integrate tactile and visual stimuli with their intuitions to explore and execute complex manipulation skills. They not only see but also feel their actions. Most current robotic learning methodologies exploit recent progress in computer vision and deep learning to acquire data-hungry pixel-to-action policies. These methodologies do not exploit intuitive latent structure in physics or tactile signatures. Tactile reasoning is omnipresent in the animal kingdom, yet it is underdeveloped in robotic manipulation. Tactile stimuli are only acquired through invasive interaction, and interpretation of the data stream together with visual stimuli is challenging. Here, we propose a methodology to emulate hierarchical reasoning and multisensory fusion in a robot that learns to play Jenga, a complex game that requires physical interaction to be played effectively. The game mechanics were formulated as a generative process using a temporal hierarchical Bayesian model, with representations for both behavioral archetypes and noisy block states. This model captured descriptive latent structures, and the robot learned probabilistic models of these relationships in force and visual domains through a short exploration phase. Once learned, the robot used this representation to infer block behavior patterns and states as it played the game. Using its inferred beliefs, the robot adjusted its behavior with respect to both its current actions and its game strategy, similar to the way humans play the game. We evaluated the performance of the approach against three standard baselines and show its fidelity on a real-world implementation of the game.

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Introducción. La tromboendarterectomía (TEA) carotídeaes el procedimiento de elección para estenosis graves,especialmente si son sintomáticas, en pacientes menores de80 años. En poblaciones ancianas hay estudios que documentanla persistencia del beneficio del procedimiento; además,otros tratamientos no han demostrado tanta eficacia o sehan acompañado de frecuentes complicaciones. Este estudiodescribe las características clínicas, resultados quirúrgicosy evolución de los pacientes mayores de 75 y 80 añosintervenidos en nuestro centro en relación con los más jóvenes.Métodos. Durante los años 2000 a 2006 fueron intervenidos86 pacientes, 8 de ellos bilateralmente. Se realizaun estudio retrospectivo que describe datos relativos a lascaracterísticas clínicas y evolución de los pacientes endarterectomizados,así como comparativo entre los distintos gruposde edad.Resultados. Fueron intervenidos 26 pacientes mayoresde 75 años, de ellos 6 eran mayores de 80 años. En los pacientesmayores el factor de riesgo fundamental fue la hipertensiónarterial, hubo menor proporción de fumadores ymayor frecuencia de estenosis grave u oclusión contralateral.Las estenosis intervenidas fueron más graves y con característicasmás agresivas. No se detectó mayor comorbilidado riesgo anestésico que en los pacientes más jóvenes.Los resultados quirúrgicos, la tasa de complicaciones perioperatoriasy la evolución a corto y medio plazo fue similaren los distintos grupos de edad (morbilidad y mortalidad inmediatapor accidente isquémico transitorio, infarto cerebralo muerte: 0% en mayores de 75 años frente a 4,41%en menores de 75 años).Conclusiones. Nuestros resultados apoyan que la edadno debe considerarse una contraindicación para la realizaciónde una TEA carotídea si existe una indicación quirúrgicaclara y una morbilidad y riesgo anestésico aceptables, comoen otros grupos poblacionales (AU)

Introduction. Carotid thromboendarterectomy is thetechnique of choice for treating high-grade stenosis inpatients less than 80 years of age, especially if they aresymptomatic. Previous studies have also documented thepersistence of the benefit of the procedure in elderly populationsand, in addition, other treatments have notbeen demonstrated to be as effective or have been relatedto more frequent complications. This study describes theclinical characteristics, surgical results and outcome ofpatients older than 75 and 80 years old, treated by thromboendarterectomyin our center in comparison with ayounger population.Methods. Between the years 2000 to 2006, 86 patientswere treated by thromboendarterectomy, 8 of thembilaterally. A retrospective study that described the dataregarding clinical characteristics and outcome of the patientswho had undergone endarterectomy was conductedand the different age groups were compared.Results. Twenty-six patients older than 75 years old,6 of whom were older than 80, were operated on. In theelderly patients, the fundamental risk factor was highblood pressure, there was a lower proportion of smokersand a higher proportion of contralateral severe stenosisor occlusion. Stenosis treated by surgery was more severeand had more aggressive characteristics. Comorbidityand anesthetic risk were the same as in younger patients.Surgical results, perioperative complication rates andshort and long term outcome were similar in the differentage groups (immediate morbidity-mortality due totransitory ischemic accident, stroke or death: 0% in408 older than 75 vs. 4.41% in those under 75). Conclusions. Our results support that age should notbe considered a contraindication for the performance ofa carotid thromboendarterectomy if there is a clear indicationand acceptable morbidity and anesthetic risk, asin other population groups (AU)

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INTRODUCTION: Carotid thromboendarterectomy is the technique of choice for treating highgrade stenosis in patients less than 80 years of age, especially if they are symptomatic. Previous studies have also documented the persistence of the benefit of the procedure in elderly populations and, in addition, other treatments have not been demonstrated to be as effective or have been related to more frequent complications. This study describes the clinical characteristics, surgical results and outcome of patients older than 75 and 80 years old, treated by thromboendarterectomy in our center in comparison with a younger population. METHODS: Between the years 2000 to 2006, 86 patients were treated by thromboendarterectomy, 8 of them bilaterally. A retrospective study that described the data regarding clinical characteristics and outcome of the patients who had undergone endarterectomy was conducted and the different age groups were compared. RESULTS: Twenty-six patients older than 75 years old, 6 of whom were older than 80, were operated on. In the elderly patients, the fundamental risk factor was high blood pressure, there was a lower proportion of smokers and a higher proportion of contralateral severe stenosis or occlusion. Stenosis treated by surgery was more severe and had more aggressive characteristics. Comorbidity and anesthetic risk were the same as in younger patients. Surgical results, perioperative complication rates and short and long term outcome were similar in the different age groups (immediate morbidity-mortality due to transitory ischemic accident, stroke or death: 0% in older than 75 vs. 4.41% in those under 75). CONCLUSIONS: Our results support that age should not be considered a contraindication for the performance of a carotid thromboendarterectomy if there is a clear indication and acceptable morbidity and anesthetic risk, as in other population groups.

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El presente documento trata de las campañas de Vacunación tanto en el area urbana como rural con el objeto de inmunizar a los niños que no pueden asistir a los servicios de salud. Cada Distrito sanitario es responsable de estas actividades y las define de acuerdo a sus caracteristicas locales.

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The 2-month results of a study designed to compare the effectiveness of three methods to encourage giving up smoking in primary health care are reported: individualized medical counseling (minimal intervention), counseling plus follow-up option by the nurse, and medical counseling plus nicotine chewing gum. Overall 425 smokers between 15 and 65 years of age were included in the study. In 349 of them (82%), short term follow-up was carried out by phone interview. The proportion who declared to have given up smoking, after adjustment for the estimated validity of the phone report of smoking status, was 10, 9%, 10.8% and 11.1%, respectively, without significant differences between the three groups. In the logistic regression analysis, only the existence of concomitant disease and the anticipated difficulty in giving up smoking appeared as predictive variables of abstention. The implications of the results for the strategies to control smoking are discussed.

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Normally, axons within the corpus callosum are ordered according to the cortical regions from which they originate, and callosal cells and terminations form elaborate cortical patterns related to the underlying topographic representations of the sensory periphery. About 30% of mice of the BALB/c strain show congenital deficiencies of the callosal commissure which range from total absence of the corpus callosum to a moderate reduction in the size of this commissure. In the light of current theories about the origin of these callosal deficiencies, it seems likely that fibers crossing the midplane in mutant mice have to circumvent local disturbances along their migration path. Since these disturbances in fiber trajectory may, in turn, alter the overall pattern of callosal projections, we set out to investigate whether the distribution of callosal connections in mice with marked deficiencies of the corpus callosum is as ordered as in normal mice. In groups of normal and mutant mice, we used multiple injections of horseradish peroxidase to reveal the overall distribution of callosal connections and restricted injections of horseradish peroxidase conjugated with wheat germ agglutinin to reveal finer aspects of the organization of the callosal pathway in these animals. Our results show that the number of labeled cells is reduced in mice with a small corpus callosum and that no labeled cells are present in the neocortex of acallosal mice. Furthermore, the topographic distribution of fibers within the corpus callosum of mutant mice can be significantly less ordered than in normal mice. However, even in mice with extreme deficiencies of the corpus callosum, callosal fibers originate from and terminate in all major areas of the cortex, and, within these areas, callosal cells and terminations are distributed according to the normal plan. The laminar distribution of callosal cells also appears normal in these mice. These findings indicate that gross developmental anomalies of the corpus callosum do not prevent normal specification of the callosal pattern during development. Within the context of current theories about the origin of congenital callosal deficiencies, our findings suggest that callosal fibers are able to establish appropriate contralateral connections in spite of alterations of their migration route. They also suggest that fiber topography within the corpus callosum does not play an important role in guiding migrating axons to their correct contralateral targets. Finally, our failure to find labeled fibers within the anterior commissure indicates that this commissure does not serve as an alternative route for deviated callosal axons.

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