Coordinated neuronal ensembles in primary auditory cortical columns.

The synchronous activity of groups of neurons is increasingly thought to be important in cortical information processing and transmission. However, most studies of processing in the primary auditory cortex (AI) have viewed neurons as independent filters; little is known about how coordinated AI neuronal activity is expressed throughout cortical columns and how it might enhance the processing of auditory information. To address this, we recorded from populations of neurons in AI cortical columns of anesthetized rats and, using dimensionality reduction techniques, identified multiple coordinated neuronal ensembles (cNEs), which are groups of neurons with reliable synchronous activity. We show that cNEs reflect local network configurations with enhanced information encoding properties that cannot be accounted for by stimulus-driven synchronization alone. Furthermore, similar cNEs were identified in both spontaneous and evoked activity, indicating that columnar cNEs are stable functional constructs that may represent principal units of information processing in AI

Enterprise Architecture Approach for Project Management and Project-Based Organizations: A Review

Project-based organizations (PBOs) derive income from conducting projects for their clients. Maintaining the most effective and efficient project governance style is an ongoing process for these organizations as the context continuously changes. Enterprise architecture (EA) is a systemic approach that supports organizations in modeling and describing themselves in different layers, such as strategy, business, application, and technology. This literature review describes the current state of EA usage in improving and quickly revising project management governance in PBOs to benefit practitioners and researchers for an integrated view of EA, PM, and PBO, and identification of future research gaps. This review used an EA model composed of layers as an analytical framework. The extracted bibliometric and content data from selected articles were processed using the VOSviewer tool for identifying and understanding the relationships between main concepts through network mapping. The selected articles are oriented to internal organization projects, mainly in information technology (IT). The need to align projects with business is highlighted, with EA positioned as a governance tool. It was found that application of EA in PBOs is rare. A trend toward using popular PM and EA frameworks, such as PMBOK and ArchiMate, was observed

Columnar Connectivity and Laminar Processing in Cat Primary Auditory Cortex

Radial intra- and interlaminar connections form a basic microcircuit in primary auditory cortex (AI) that extracts acoustic information and distributes it to cortical and subcortical networks. Though the structure of this microcircuit is known, we do not know how the functional connectivity between layers relates to laminar processing.We studied the relationships between functional connectivity and receptive field properties in this columnar microcircuit by simultaneously recording from single neurons in cat AI in response to broadband dynamic moving ripple stimuli. We used spectrotemporal receptive fields (STRFs) to estimate the relationship between receptive field parameters and the functional connectivity between pairs of neurons. Interlaminar connectivity obtained through cross-covariance analysis reflected a consistent pattern of information flow from thalamic input layers to cortical output layers. Connection strength and STRF similarity were greatest for intralaminar neuron pairs and in supragranular layers and weaker for interlaminar projections. Interlaminar connection strength co-varied with several STRF parameters: feature selectivity, phase locking to the stimulus envelope, best temporal modulation frequency, and best spectral modulation frequency. Connectivity properties and receptive field relationships differed for vertical and horizontal connections.Thus, the mode of local processing in supragranular layers differs from that in infragranular layers. Therefore, specific connectivity patterns in the auditory cortex shape the flow of information and constrain how spectrotemporal processing transformations progress in the canonical columnar auditory microcircuit

A. Escalona Ramos, Geopolítica mundial y geoeconomía. Dinámica mundial, histórica y contemporánea, México, Ediciones Ateneo, 1959, 509 p.

Fil: Atencio, Jorge E.. Universidad Nacional de Cuyo. Facultad de Filosofía y Letra

Fierre Célérier, Géopolitique et géostrategie, Paris, Presses Universitaires de France (Col. Que Sais-je?), 1955, 127 p.

Fil: Atencio, Jorge E.. Universidad Nacional de Cuyo. Facultad de Filosofía y Letra

Propuesta de manual para el desarrollo de los procedimientos generales para la aplicación del artículo VII del GATT-OMC (Valoración aduanera).

Objetivo General * Crear una propuesta de Manual para el desarrollo de procedimientos generales para la aplicación del Articulo VII del GATT-OMC (Valoración Aduanera). Objetivos Específicos * Analizar cada uno de los procedimientos de valoración utilizados en aduanas por los exportadores, importadores y operadores económicos. * Integrar de manera secuencia¡ todos los procedimientos identificados en el desarrollo de los procedimientos generales para la aplicación del artículo VII * Presentar un Manual didáctico, interactivo y fácil de manejar que contenga en breves reseñas los procedimientos generales para la aplicación del artículo VII

Sulfur-bearing monazite-(Ce) from the Eureka carbonatite, Namibia: oxidation state, substitution mechanism, and formation conditions

Sulfur-bearing monazite-(Ce) occurs in silicified carbonatite at Eureka, Namibia, forming rims up to ~0.5 mm thick on earlier-formed monazite-(Ce) megacrysts. We present X-ray photoelectron spectroscopy data demonstrating that sulfur is accommodated predominantly in monazite-(Ce) as sulfate, via a clino-anhydrite-type coupled substitution mechanism. Minor sulfide and sulfite peaks in the X-ray photoelectron spectra, however, also indicate that more complex substitution mechanisms incorporating S2– and S4+ are possible. Incorporation of S6+ through clino-anhydrite-type substitution results in an excess of M2+ cations, which previous workers have suggested is accommodated by auxiliary substitution of OH– for O2–. However, Raman data show no indication of OH–, and instead we suggest charge imbalance is accommodated through F– substituting for O2–. The accommodation of S in the monazite-(Ce) results in considerable structural distortion that may account for relatively high contents of ions with radii beyond those normally found in monazite-(Ce), such as the heavy rare earth elements, Mo, Zr and V. In contrast to S-bearing monazite-(Ce) in other carbonatites, S-bearing monazite-(Ce) at Eureka formed via a dissolution–precipitation mechanism during prolonged weathering, with S derived from an aeolian source. While large S-bearing monazite-(Ce) grains are likely to be rare in the geological record, formation of secondary S-bearing monazite-(Ce) in these conditions may be a feasible mineral for dating palaeo-weathering horizons

Reproducción inducida de la liseta Leporinus muyscorum (Steindachner, 1902) con extracto pituitario de carpa (EPC).

La Liseta Leporinus muyscorum (Steindachner 1902) presenta características de importancia para la piscicultura, dentro de las cuales se destacan su adaptación a dietas artificiales y la calidad de su carne. No se reproduce en confinamiento, siendo necesaria su reproducción inducida con sustancias hormonales. Con reproductores capturados en el río Sinú en noviembre de 1999 y luego mantenidos en confinamiento hasta mayo de 2000 en el Centro Piscícola San Gabriel de la Corporación de los Valles del Sinú y San Jorge (CVS, Córdoba, Colombia), se logró su reproducción inducida con extracto pituitario de carpa (EPC) por primera vez en el país. Se utilizaron cuatro dosificaciones 1, 3, 5, 7 mg EPC/Kg. La dosis se dividió en dos aplicaciones en las hembras, correspondiendo 10 y 90% de la dosis total, con un intervalo de 12 horas. En los machos se aplicó una sola dosis única, equivalente al 80% de la dosis total de las hembras