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Switch 2.0 is an open-source platform for planning transitions to low-emission electric power systems, designed to satisfy 21st century grid planning requirements. Switch is capable of long-and short-term planning of investments and operations with conventional or smart grids, integrating large shares of renewable power, storage and/or demand response. Applications include integrated resource planning, investment planning, economic and policy analyses as well as basic research. Switch 2.0 includes a complete suite of power system elements, including unit commitment, part-load efficiency, planning and operating reserves, fuel supply curves, storage, hydroelectric networks, policy constraints and demand response. It uses a robust, modular architecture that allows users to compose models by choosing built-in modulesà la carte or writing custom modules.

BackgroundHumans and other animals change the way they perceive the world due to experience. This process has been labeled as perceptual learning, and implies that adult nervous systems can adaptively modify the way in which they process sensory stimulation. However, the mechanisms by which the brain modifies this capacity have not been sufficiently analyzed.Methodology/Principal FindingsWe studied the neural mechanisms of human perceptual learning by combining electroencephalographic (EEG) recordings of brain activity and the assessment of psychophysical performance during training in a visual search task. All participants improved their perceptual performance as reflected by an increase in sensitivity (d') and a decrease in reaction time. The EEG signal was acquired throughout the entire experiment revealing amplitude increments, specific and unspecific to the trained stimulus, in event-related potential (ERP) components N2pc and P3 respectively. P3 unspecific modification can be related to context or task-based learning, while N2pc may be reflecting a more specific attentional-related boosting of target detection. Moreover, bell and U-shaped profiles of oscillatory brain activity in gamma (30–60 Hz) and alpha (8–14 Hz) frequency bands may suggest the existence of two phases for learning acquisition, which can be understood as distinctive optimization mechanisms in stimulus processing.Conclusions/SignificanceWe conclude that there are reorganizations in several neural processes that contribute differently to perceptual learning in a visual search task. We propose an integrative model of neural activity reorganization, whereby perceptual learning takes place as a two-stage phenomenon including perceptual, attentional and contextual processes.

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Alternatives for the closure of extremity fasciotomyFasciotomy is the mainstay of treatment and prevention of acute compartment syndrome. Given the important deep tissue edema, closure of the resulting wound generates a significant reconstructive challenge for the surgeon. The aim of this article is to provide an update concerning alternatives for closure of fasciotomy of limbs, for which a search of articles indexed in PubMed, Scielo and Epistemonikos databases was performed. At least 6 techniques were found, each of them with specific advantages and disadvantages. We recommend that the choice should be according to the surgeons experience, resources and context of each patient. Key words: fasciotomy; compartment syndromes; wound closure techniques; extremities. ResumenLa fasciotomía es el pilar del tratamiento y prevención del síndrome compartimental agudo. Una vez resuelto el cuadro agudo que derivó en la necesidad de ésta, el cierre de la herida resultante genera un importante desafío reconstructivo para el cirujano dado el importante edema residual de los tejidos. El objetivo de este artículo es entregar una actualización respecto a las alternativas de cierre de una fasciotomía de extremidades, para lo cual se realizó una búsqueda de artículos indexados en PubMed, Epistemonikos y Scielo. Se encontraron al menos 6 técnicas disponibles, cada una de ellas con determinadas ventajas y desventajas. Recomendamos que la elección sea de acuerdo a la experiencia del cirujano, los recursos disponibles y el contexto de cada paciente. Palabras clave: fasciotomía; cierre de heridas; síndrome compartimental; extremidades. IntroducciónLa fasciotomía es el pilar del tratamiento y prevención del síndrome compartimental agudo (SCA). Sin embargo, una vez resuelta la causa que produjo o condujo a la necesidad de la liberación del compartimiento, la herida resultante prolonga de forma significativa la estadía hospitalaria y su cierre genera un gran desafío reconstructivo 1 . En la literatura internacional se estima una incidencia anual de SCA en una extremidad traumatizada de 7,3 por 100.000 hombres y 7,0 por 100.000 mujeres 2 . El SCA consiste en el aumento progresivo de la presión dentro de un compartimento osteofascial cerrado, que sobrepasa en primer lugar la presión venosa, causando gran edema, lo que contribuye finalmente a sobrepasar la presión arterial de perfusión de la extremidad, generando isquemia de los tejidos que de no ser tratada oportunamente evoluciona hacia la necrosis, pérdida de la extremidad y en raros casos, la muer-