Spatial Panel Data Forecasting over Different Horizons, Cross-Sectional and Temporal Dimensions

Empirical assessments of the forecasting power of spatial panel data econometric models are still scarcely available. Moreover, several methodological contributions rely on simulated data to showcase the potential of proposed methods. While simulations may be useful to evaluate the properties of a single estimator, the empirical set-ups of simulation studies are often based on strong assumptions regarding the shape and regularity of the statistical distribution of the variables involved. It is then valuable to have, next to simulation studies, empirical assessments of competing econometric models based on real data. In this paper, we evaluate competing spatial (dynamic) panel methods, selecting a number of data sets characterized by a range of different cross-sectional and temporal dimensions, as well as different levels of spatial auto-correlation. We carry out our empirical exercise on regional unemployment data for France, Spain and Switzerland. Additionally, we test different forecasting horizons, in order to investigate the speed of deterioration of forecasting quality. We compare two classes of methods: spatial vector autoregressive (SVAR) models and dynamic panel models making use of eigenvector spatial filtering (SF). We find that, as it could be expected, the unbalance between the temporal and cross-sectional dimension (T>>n) does play in favour of the SVAR model. On the other hand, the advantage of the SVAR model over the SF model appears to diminish as the forecasting horizon widens, eventually leading the SF model to being preferred for more distant forecasts

Plinio y la minería aurífera romana: nueva traducción e interpretación de PLIN.Nat.33.66-78

Readers are presented with a new translation and an original interpretation of PLIN.Nat.33.66-78, text about the gold-bearing Roman mining in the Iberian Peninsula. This work is the result of an interdisciplinary focus, in which the knowledge of the Latin language and the techniques of the Roman mining have come together and have been extremely respected, given that the authors´ main aim has been to get as close as possible to what Pliny the Elder wanted to express, as well as to determine exactly his knowledge about the true dimension of the techniques used in the exploitation of the gold mines in the Roman Empire.El lector tiene ante sí una nueva traducción y una novedosa interpretación de PLIN.Nat.33.66-78, texto dedicado a la minería aurífera romana de la Península Ibérica. Este trabajo es el resultado de un enfoque interdisciplinar, en el que el conocimiento de la lengua latina y las técnicas de minería romana han confluido y se han respetado en grado sumo, pues el objetivo principal de los autores ha sido acercarse lo más posible a lo que Plinio el Viejo quiso expresar, así como matizar con precisión su grado de conocimiento sobre la verdadera dimensión de las técnicas utilizadas en la explotación de las minas de oro en el Imperio Romano

Unravelling stellar populations in the Andromeda Galaxy

To understand the history and formation mechanisms of galaxies it is crucial to determine their current multidimensional structure. Here we focus on stellar population properties, such as metallicity and [$\alpha$/Fe] enhancement. We devise a new technique to recover the distribution of these parameters using spatially resolved, line-of-sight averaged data. Our chemodynamical method is based on the made-to-measure (M2M) framework and results in an $N$-body model for the abundance distribution. We test our method on a mock data set and find that the radial and azimuthal profiles are well-recovered, however only the overall shape of the vertical profile matches the true profile. We apply our procedure to spatially resolved maps of mean [Z/H] and [$\alpha$/Fe] for the Andromeda Galaxy, using an earlier barred dynamical model of M31. We find that the metallicity is enhanced along the bar, with possible maxima at the ansae. In the edge-on view the [Z/H] distribution has an X shape due to the boxy/peanut bulge; the average vertical metallicity gradient is equal to $-0.133\pm0.006$ dex/kpc. We identify a metallicity-enhanced ring around the bar, which also has relatively lower [$\alpha$/Fe]. The highest [$\alpha$/Fe] is found in the centre, due to the classical bulge. Away from the centre, the $\alpha$-overabundance in the bar region increases with height, which could be an indication of a thick disc. We argue that the galaxy assembly resulted in a sharp peak of metallicity in the central few hundred parsecs and a more gentle negative gradient in the remaining disc, but no [$\alpha$/Fe] gradient. The formation of the bar lead to the re-arrangement of the [Z/H] distribution, causing a flat gradient along the bar. Subsequent star formation close to the bar ends may have produced the metallicity enhancements at the ansae and the [Z/H] enhanced lower-$\alpha$ ring.Comment: 20 pages, 17 figures, 1.9MB, accepted to A&

Influence of the spatial distribution of border traps in the capacitance frequency dispersion of Al2O3/InGaAs

In this paper, the capacitance frequency dispersion in strong accumulation of capacitance voltage curves has been studied for different high-k dielectric layers in MOS stacks. By studying experimental data at low (77 K) and room temperature (300 K), in oxides with different density of defects, it was possible reflect the spatial distribution of the defects in the capacitance frequency dispersion. The experimental data show that while at room temperature, the capacitance dispersion is dominated by the exchange of carriers from the semiconductor into oxide traps far away from the interface, at low temperature the oxide traps near the Al2O3/InGaAs interface are responsible for the frequency dispersion. The results indicate that the capacitance dispersion in strong accumulation reflect the spatial distribution of traps within the oxide, and that dielectric/semiconductor conduction band offset is a critical parameter for determining the capacitance dispersion for Al2O3/InGaAs based gate stacks.Fil: Palumbo, Félix Roberto Mario. Comisión Nacional de Energía Atómica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional; ArgentinaFil: Aguirre, Fernando Leonel. Universidad Tecnológica Nacional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica; ArgentinaFil: Pazos, Sebastián Matías. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional; Argentina. Comisión Nacional de Energía Atómica; ArgentinaFil: Krylov, Igor. Technion - Israel Institute of Technology; IsraelFil: Winter, Roy. Technion - Israel Institute of Technology; IsraelFil: Eizenberg, Moshe. Technion - Israel Institute of Technology; Israe

Aproximaciones a las miradas de los trabajadores de la policía de Neuquén, en relación con las masculinidades, diversidades y violencias

The following article aims to investigate the perspectives of police workers in the province of Neuquén regarding masculinities, gender and diversity.The article is based on the elaboration and diffusion of an anonymous survey (2022) directed specifically to men who transit or transited the police institution, which allows us to know certain characterizations that are perceived on the proposed topics.On the other hand, comparative analyzes were carried out with the results of anonymous surveys carried out in previous years in heterogeneous groups of men and women who make up the police institution.El siguiente trabajo indaga sobre las perspectivas de los trabajadores varones que integran la policía de la provincia de Neuquén con respecto a las masculinidades, el género y las diversidades.En un primer momento se elaboró y difundió una encuesta anónima (2022) dirigida específicamente a varones que transitan o transitaron la institución policial, lo que nos permitió conocer ciertas caracterizaciones que perciben sobre las temáticas propuestas.Por otro lado, se realizó un análisis comparativo con resultados de encuestas anónimas, realizadas en años anteriores en grupos heterogéneos de varones y de mujeres que integran la institución policial

The Canals of Las Médulas (León-Spain): Reasons for its Inclusion in the World Heritage

A declaração em 1997 da exploração romana de ouro de Las Médulas como Patrimônio da Humanidade foi um reconhecimento merecido da maior exploração de mineração do mundo antigo. No entanto, essa afirmação ignorou a totalidade deste magnífico trabalho de engenharia, concentrando-se apenas no local único dos picos vermelhos, resíduos dos trabalhos de extração. Desse modo, ficaram de fora os canais de abastecimento de água, essenciais para o colapso da montanha, um sistema que o naturalista romano Plínio chama «arrugia», e a recuperação de ouro nos canais de lavagem./nNaquela época, parece que os canais eram considerados um trabalho menor e eram pouco documentados, com a absoluta falta de topografia adequada, apesar de serem amplamente conhecidos pelos nativos da região. Somente em 2004 foi publicada a primeira cartografia detalhada, que agora mostra a surpreendente figura de 600 km de canais, expandida sucessivamente com novas pesquisas e descobertas em 2008 e 2017, para as quais os 700 km de passeio./nPara as Medulas, chegaram alguns canais de 147 e 124 km, que corroboram os números de cem milhas que Plínio menciona. Este último canal fez uma importante transferência de águas da Bacia do Douro para a Bacia do Sil. A estrutura de suprimentos revela a existência de diferentes fases do trabalho no depósito de ouro e um detalhe muito importante: a operação foi interrompida por exaustão. A magnitude deste trabalho de engenharia, essencial para a existência das próprias Medulas, não pode passar despercebida e, sem dúvida, merece o reconhecimento homônimo de que o objeto para o qual foi construído já recebeu.La declaración en 1997 de la explotación aurífera romana de Las Médulas como Patrimonio de la Humanidad supuso un merecido reconocimiento a la mayor explotación minera del Mundo Antiguo. Sin embargo, esta declaración pasó por alto el conjunto de esta magnífica obra de ingeniería, centrándose únicamente en el singular paraje de picachos rojos, residuos de los trabajos de extracción. De este modo, quedaron al margen los canales de abastecimiento de agua, imprescindibles para poder realizar el derrumbe de la montaña, sistema que el naturalista romano Plinio denomina arrugia, y permitir la recuperación del oro en los canales de lavado. En ese momento, parece ser que los canales fueron considerados como una obra menor y se encontraban muy escasamente documentados, con la carencia absoluta de una topografía adecuada, a pesar de ser ampliamente conocidos por los naturales de la zona. No es hasta el año 2004 cuando se publica la primera cartografía de detalle, que arroja ya la sorprendente cifra de 600 km de canales, sucesivamente ampliados con nuevas investigaciones y hallazgos en el 2008 y 2017, por lo que se alcanzan ya los 700 km de recorrido. A las Médulas llegaban algunos canales de 147 y 124 km, que corroboran las cifras de cien millas que menciona Plinio. Este último canal realizó un importante trasvase de aguas de la Cuenca del Duero a la Cuenca del Sil. La estructura de abastecimiento desvela la existencia de distintas fases de trabajo en el yacimiento aurífero y un detalle muy importante: la explotación se interrumpió por agotamiento. La magnitud de esta obra de ingeniería, imprescindible para la existencia de las propias Médulas, no puede pasar desapercibida, y sin duda merece el reconocimiento homónimo que ya ha recibido el objeto para el que fue construido.The declaration in 1997 of the Roman gold exploitation of Las Médulas as a World Heritage Site was a well-deserved recognition of the largest mining exploitation in the Ancient World. However, this statement overlooked the entirety of this magnificent engineering work, focusing solely on the unique spot of red peaks, residues of the extraction works. In this way, the water supply canals, essential to carry out the collapse of the mountain, a system that the Roman naturalist Pliny calls «arrugia», and the recovery of gold in the washing canals, were left out./nAt that time, it seems that the canals were considered a minor work and were very scarcely documented, with the absolute lack of adequate topography, despite being widely known to the natives of the area. It was not until 2004 when the first detailed cartography was published, which now shows the surprising figure of 600 km of canals, successively expanded with new research and findings in 2008 and 2017, for which the 700 km of travel./nSome of this canals reached 147 and 124 km, which corroborate the figures of one hundred miles that Pliny mentions. This last canal made an important transfer of water from the Duero Basin to the Sil Basin. The supply structure reveals the existence of different phases of work in the gold deposit and a very important detail: the operation was interrupted due to exhaustion. The magnitude of this engineering work, essential for the existence of Las Médulas themselves, cannot go unnoticed, and undoubtedly deserves the homonymous recognition that the object for which it was built has already received

Metodología de relación para evaluar la compactación en capas granulares de un pavimento flexible

El enfoque que tiene esta investigación es cuantitativo, que surge ante el problema causado por el deterioro de un pavimento, como huecos, ahuellamientos, hundimientos, trazándose como objetivo determinar una metodología de relación a fin de evaluar, la compactación de las capas granulares de un pavimento, a través de una ecuación lineal obtenida con las datas de campo. Para solucionarlo, previo a la ejecución de capas estructurales de suelos en un pavimento flexible, se recurrió, al estudio de los materiales, correlación de equipo del cono de arena con el densímetro nuclear y el uso del equipo LWD para obtener, una metodología de prospección del suelo, que proporcione datos de campo en capas granulares de un pavimento flexible. Al término de la conformación de capas granulares, se realizó ensayos in situ con un equipo liviano portátil denominado Light Falling Weight Deflectometer y densímetro nuclear, el cual, con la data proporcionada, se determinó una metodología de relación de soporte estructural que, determina el grado de compactación usando el equipo LWD, relacionando los resultados de densidad y deflexión. Con los datos de modulo dinámico proporcionados por el equipo Light Falling Weight Deflectometer y datos de grado de compactación proporcionado por el equipo densímetro nuclear, se determinó una metodología de relación de resistencia estructural, obteniendo como resultado en una ecuación lineal un parámetro de bondad R2 está entre 0.70 a 0.89, considerado como una aceptación de resultados buenos

Caracterización de almohadillas liberadoras de SO2 en base a proteínas de soja para la prevención de pardeamiento en manzanas frescas cortadas

The use of polymeric matrices releasing active principles is a promising strategy to circumvent dipping treatments and reduce additive usage. Herein, we developed soy protein-based films containing 0, 10, 25 or 50% sodium sulfite on protein isolate basis (SPI), and determined the influence of the antioxidant on the color, thickness, opacity, solubility, moisture, water permeability and mechanical properties of the resulting materials. Raising sulfite concentration reduced the tensile strength, without affecting the Young´s modulus of the films. The formulation containing 50% sodium sulfite on SPI basis was selected based on the lighter color, lowest moisture and higher permeability of the resulting films to evaluate the efficacy of the materials to prevent apple browning. The incorporation of SO2-releasers in packages containing fresh-cut apples delayed fruit yellowing (increase of b*values) by 40%. This shows that sodium sulfite soy protein based films may be useful to extend the postharvest life of fresh-cut apple.Centro de Investigación y Desarrollo en Criotecnología de AlimentosLaboratorio de Investigación en Productos Agroindustriale