Expansión física y demográfica y cambios en la densidad de la Aglomeración Gran Buenos Aires, 1750-2010

El objetivo de este artículo es presentar series de datos inéditos sobre los procesos de expansión física y demográfica de la Aglomeración Gran Buenos Aires (AGBA) desde 1750 a 2010 y, particularmente, examinar los cambios en la densidad de habitantes. En la primera parte se revisan los antecedentes directos de este trabajo y se establecen las limitaciones actuales en el campo de estudio que aquí proponemos franquear, en términos metodológicos y de disponibilidad de datos. En la sección metodológica se explican los criterios adoptados en la elaboración de la serie que aseguran su consistencia y comparabilidad. Las conclusiones destacan las tendencias macro -tal como la que da cuenta del significativo descenso de la densidad de la AGBA en los últimos 140 años- y las tendencias particulares que informan variaciones entre períodos. En ambos casos, se proponen hipótesis explicativas apoyadas en información secundaria y registros historiográficos.The purpose of this paper is to present a series of unpublished data on the processes of physical and demographic expansion of the Greater Buenos Aires Agglomeration (agba) from 1750 to 2010 and, in particular, to examine changes in population density. In the first part of the article, the direct bibliographical references are reviewed, and the gaps that we intend to fill here –both in terms of methodology and data availability– are presented. Afterwards, we discuss the operational and methodological considerations which ensure the comparability of the series. Finally, the conclusions highlight both the trends at a macro level –such as the significant decrease in the population density of the agba over the last 140 years– and the more particular ones that report nuances and variations in between periods. In both cases, explanatory hypotheses supported by secondary data and specific historiographical records for each of the periods analyzed are proposed.Fil: Rodriguez, Gonzalo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Centro de Estudios Urbanos y Regionales; ArgentinaFil: Kozak, Daniel Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Centro de Estudios Urbanos y Regionales; Argentina. Universidad de Buenos Aires. Facultad de Arquitectura y Urbanismo; Argentin

Prefrontal Acetylcholine Release Controls Cue Detection on Multiple Timescales

SummaryCholinergic neurons originating from the basal forebrain innervate the entire cortical mantle. Choline-sensitive microelectrodes were used to measure the synaptic release of cortical acetylcholine (ACh) at a subsecond resolution in rats performing a task involving the detection of cues. Cues that were detected, defined behaviorally, evoked transient increases in cholinergic activity (at the scale of seconds) in the medial prefrontal cortex (mPFC), but not in a nonassociational control region (motor cortex). In trials involving missed cues, cholinergic transients were not observed. Cholinergic deafferentation of the mPFC, but not motor cortex, impaired cue detection. Furthermore, decreases and increases in precue cholinergic activity predicted subsequent cue detection or misses, respectively. Finally, cue-evoked cholinergic transients were superimposed over slower (at the timescale of minutes) changes in cholinergic activity. Cortical cholinergic neurotransmission is regulated on multiple timescales to mediate the detection of behaviorally significant cues and to support cognitive performance

Study of the sound absorption properties of 3D-printed open-porous ABS material structures

Noise pollution is a negative factor that affects our environment. It is, therefore, necessary to take appropriate measures to minimize it. This article deals with the sound absorption properties of open-porous Acrylonitrile Butadiene Styrene (ABS) material structures that were produced using 3D printing technology. The material's ability to damp sound was evaluated based on the normal incidence sound absorption coefficient and the noise reduction coefficient, which were experimentally measured by the transfer function method using an acoustic impedance tube. The different factors that affect the sound absorption behavior of the studied ABS specimens are presented in this work. In this study, it was discovered that the sound absorption properties of the tested ABS samples are significantly influenced by many factors, namely by the type of 3D-printed, open-porous material structure, the excitation frequency, the sample thickness, and the air gap size behind the sound-absorbing materials inside the acoustic impedance tube. © 2020 by the authors.Ministry of Education, Science, Research, and Sport of the Slovak Republic [KEGA 007TUKE-4/2018, APVV-19-0550]; European Regional Development Fund in the Research Centre of Advanced Mechatronic Systems within the Operational Programme Research, Development, and Education [CZ.02.1.01/0.0/0.0/16_019/0000867

Stringency of start codon selection modulates autoregulation of translation initiation factor eIF5

An AUG in an optimal nucleotide context is the preferred translation initiation site in eukaryotic cells. Interactions among translation initiation factors, including eIF1 and eIF5, govern start codon selection. Experiments described here showed that high intracellular eIF5 levels reduced the stringency of start codon selection in human cells. In contrast, high intracellular eIF1 levels increased stringency. High levels of eIF5 induced translation of inhibitory upstream open reading frames (uORFs) in eIF5 mRNA that initiate with AUG codons in conserved poor contexts. This resulted in reduced translation from the downstream eIF5 start codon, indicating that eIF5 autoregulates its own synthesis. As with eIF1, which is also autoregulated through translation initiation, features contributing to eIF5 autoregulation show deep evolutionary conservation. The results obtained provide the basis for a model in which auto- and cross-regulation of eIF5 and eIF1 translation establish a regulatory feedback loop that would stabilize the stringency of start codon selection

Primary structure and functional expression of a cyclic nucleotidegated channel from rabbit aorta

Sequences specific for cyclic nucleotide-gated channels (CNG channels) have been amplified by PCR from cDNA of heart, aorta, sinoatrial node, cerebellum, C-cells and kidney. The complete amino acid sequence of a CNG channel from rabbit aorta has been deduced by cloning and sequence analysis of the cDNA. Synthetic RNA derived from this cDNA induces the formation of a functional CNG channel in Xenopus oocytes

Estación de biosfera Yabotí : Estudios para un proyecto demostrativo de bajo impacto ambiental

Este trabajo presenta los estudios realizados en el marco del convenio PNUD-FADU, subscripto para contribuir al desarrollo e implementación de criterios de sustentabilidad en el proyecto de la Estación de Biosfera Yabotí, situada en la Reserva Provincial ‘La Esmeralda’, Pcia. de Misiones, obra del Ministerio de Ecología, Recursos Naturales Renovables y Turismo. El conjunto edilicio alberga un director y dos guardaparques residentes, y 12 investigadores tesistas y pasantes realizando estudios de campo en biodiversidad. Los estudios realizados promueven el control de impactos ambientales, confort de los ocupantes con acondicionamiento natural, ahorro de energía y agua, y uso de energías renovables en Zona Bioambiental 1ª, muy cálida con baja amplitud térmica, en plena selva misionera. El proyecto, demostrativo de construcción sustentable de bajo impacto ambiental y autonomía energética, reviste especial importancia en la producción, operación y mantenimiento, elección de materiales, y provisión e implementación de servicios no-convencionales, en esta zona protegida.This paper presents studies undertaken to support the development of the UNDP Project 'Yabotí Biosphere Station' situated in the Provincial Reserva ‘La Esmeralda’, Province of Misiones. The building group, a demonstration project of low impact environmental design and energy autonomy, houses a director, 2 resident park-rangers, and 12 researchers during academic visits undertaking field studies in biodiversity. The building, located in Bioclimatic zone 1a, very hot with low thermal swing, studies aim to reduce environmental impacts, promote natural conditioning studies and occupant comfort, rational use of energy and water and use of renewable energy.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Estación de biosfera Yabotí : Estudios para un proyecto demostrativo de bajo impacto ambiental

Este trabajo presenta los estudios realizados en el marco del convenio PNUD-FADU, subscripto para contribuir al desarrollo e implementación de criterios de sustentabilidad en el proyecto de la Estación de Biosfera Yabotí, situada en la Reserva Provincial ‘La Esmeralda’, Pcia. de Misiones, obra del Ministerio de Ecología, Recursos Naturales Renovables y Turismo. El conjunto edilicio alberga un director y dos guardaparques residentes, y 12 investigadores tesistas y pasantes realizando estudios de campo en biodiversidad. Los estudios realizados promueven el control de impactos ambientales, confort de los ocupantes con acondicionamiento natural, ahorro de energía y agua, y uso de energías renovables en Zona Bioambiental 1ª, muy cálida con baja amplitud térmica, en plena selva misionera. El proyecto, demostrativo de construcción sustentable de bajo impacto ambiental y autonomía energética, reviste especial importancia en la producción, operación y mantenimiento, elección de materiales, y provisión e implementación de servicios no-convencionales, en esta zona protegida.This paper presents studies undertaken to support the development of the UNDP Project 'Yabotí Biosphere Station' situated in the Provincial Reserva ‘La Esmeralda’, Province of Misiones. The building group, a demonstration project of low impact environmental design and energy autonomy, houses a director, 2 resident park-rangers, and 12 researchers during academic visits undertaking field studies in biodiversity. The building, located in Bioclimatic zone 1a, very hot with low thermal swing, studies aim to reduce environmental impacts, promote natural conditioning studies and occupant comfort, rational use of energy and water and use of renewable energy.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES