Inferring long memory processes in the climate network via ordinal pattern analysis

We use ordinal patterns and symbolic analysis to construct global climate networks and uncover long and short term memory processes. The data analyzed is the monthly averaged surface air temperature (SAT field) and the results suggest that the time variability of the SAT field is determined by patterns of oscillatory behavior that repeat from time to time, with a periodicity related to intraseasonal oscillations and to El Ni\~{n}o on seasonal-to-interannual time scales.Comment: 10 pages, 13 figures Enlarged version, new sections and figures. Accepted in Chao

Evidence of Twisted flux-tube Emergence in Active Regions

Elongated magnetic polarities are observed during the emergence phase of bipolar active regions (ARs). These extended features, called magnetic tongues, are interpreted as a consequence of the azimuthal component of the magnetic flux in the toroidal flux-tubes that form ARs. We develop a new systematic and user-independent method to identify AR tongues. Our method is based on determining and analyzing the evolution of the AR main polarity inversion line (PIL). The effect of the tongues is quantified by measuring the acute angle [ tau] between the orientation of the PIL and the direction orthogonal to the AR main bipolar axis. We apply a simple model to simulate the emergence of a bipolar AR. This model lets us interpret the effect of magnetic tongues on parameters that characterize ARs ( e.g. the PIL inclination and the tilt angles, and their evolution). In this idealized kinematic emergence model, tau is a monotonically increasing function of the twist and has the same sign as the magnetic helicity. We systematically apply our procedure to a set of bipolar ARs that were observed emerging in line-of-sight magnetograms over eight years. For most of the cases studied, the tongues only have a small influence on the AR tilt angle since tongues have a much lower magnetic flux than the more concentrated main polarities. From the observed evolution of tau, corrected for the temporal evolution of the tilt angle and its final value when the AR is fully emerged, we estimate the average number of turns in the subphotospherically emerging flux-rope. These values for the 41 observed ARs are below unity, except for one. This indicates that subphotospheric flux-ropes typically have a low amount of twist, i.e. highly twisted flux-tubes are rare. Our results demonstrate that the evolution of the PIL is a robust indicator of the presence of tongues and constrains the amount of twist in emerging flux-tube

Hyperbranched and hiperfunctionalized materials from dendritic chemistry

Las moléculas dendríticas son altamente ordenadas, regularmente ramificadas y monodispersas. Debido a su estructura macromolecular única y bien definida, ellas constituyen una atractiva plataforma hacia una gran variedad de aplicaciones; siendo además, una fascinante herramienta para la construcción de materiales a escala nanométrica. Por lo tanto, debido a sus destacadas propiedades macromoleculares hay un gran interés en el uso de las mismas como unidades de construcción, tanto para la ciencia de polímeros como para la nanociencia. En los últimos años la investigación en el campo de la química dendrítica ha experimentado un desarrollo exponencial, tanto en el área académica como en la tecnológica. Por lo tanto, tales estructuras macromoleculares han sido extensivamente exploradas en la ciencia de los materiales, mas específicamente en áreas biomédicas. Las arquitecturas dendríticas ofrecen ventajas únicas con respecto a otras macromoléculas y polímeros convencionales, como son la presencia de múltiples grupos funcionales y su versatilidad para sufrir posteriores modificaciones químicas, baja dispersidad en pesos moleculares, baja viscosidad, reducido enredamiento molecular y tamaño nanoscópico dentro del rango de 1 a 10 nanometros. El objetivo de esta presentación es mostrar las ventajas de las estructuras dendríticas, sus principales propiedades, desarrollo y uso en varias ciencias aplicadas. Particularmente, se hará énfasis en aplicaciones biomédicas y en nanomedicina. Por lo tanto, se discutirán ejemplos claves que ilustrarán los principios más importantes en los cuales se basa la química dendrítica, y las principales aplicaciones de las estructuras dendríticas en la interface entre la química, la biología y la biomedicina.Dendritic molecules are highly ordered, regularly branched, and monodisperse macromolecules. Due to their unique and well-defined macromolecular structure they are attractive scaffolds for a variety of high-end applications and constitute a fascinating nanoscale toolkit. They are of great interest to both, nano and polymer science, as building blocks due to their unique macromolecular properties. In recent years, research in the field of dendritic chemistry has experienced an exponential development in academic and technological areas and such macromolecular structures have also been extensively explored in materials science, specifically in biomedical areas. The unique advantages offered by dendritic architectures over conventional macromolecules and polymers are the presence of multiple functional groups and their amenability to further chemical modification, extremely low molecular weight dispersity, low solution viscosity, reduced molecular entanglement, and nanoscopic size within the range of 1 to 10 nm. The objective of this review is to show the advantage of the dendritic structures, their main properties, and to reflect on their development and use in various science applications. Particular emphasis will be place on biomedical and nanomedicine applications. Therefore, key examples will be discussed to illustrate the main principles involved in dendritic chemistry, and the applications of the dendritic structures at the interfaces between chemistry, biology and biomedicine.Fil: Calderón, Marcelo. Universita Zu Berlin; AlemaniaFil: Strumia, Miriam Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); Argentina. Universidad Nacional de Córdoba; Argentin

The effect of voting rights on firm value

We present a simple framework for dual‐class stock shares in which common shareholders receive public and private cash flows (i.e., dividends and any private benefit of holding voting rights) and preferred shareholders only receive public cash flows. We isolate these two cash flows in order to identify the role of voting rights on equity‐holders' wealth. In particular, using a structural cointegrated VAR model, we find a negative relationship between the value of the voting right and the preferred shareholders' wealth

Two successive partial mini-filament confined ejections

Active region (AR) NOAA 11476 produced a series of confined plasma ejections, mostly accompanied by flares of X-ray class M, from 08 to 10 May 2012. The structure and evolution of the confined ejections resemble that of EUV surges; however, their origin is associated to the destabilization and eruption of a mini-filament, which lay along the photospheric inversion line (PIL) of a large rotating bipole. Our analysis indicate that the bipole rotation and flux cancellation along the PIL have a main role in destabilizing the structure and triggering the ejections. The observed bipole emerged within the main following AR polarity. Previous studies have analyzed and discussed in detail two events of this series in which the mini-filament erupted as a whole, one at 12:23 UT on 09 May and the other at 04:18 UT on 10 May. In this article we present the observations of the confined eruption and M4.1 flare on 09 May 2012 at 21:01 UT (SOL2012-05-09T21:01:00) and the previous activity in which the mini-filament was involved. For the analysis we use data in multiple wavelengths (UV, EUV, X-rays, and magnetograms) from space instruments. In this particular case, the mini-filament is seen to erupt in two different sections. The northern section erupted accompanied by a C1.6 flare and the southern section did it in association with the M4.1 flare. The global structure and direction of both confined ejections and the location of a far flare kernel, to where the plasma is seen to flow, suggest that both ejections and flares follow a similar underlying mechanism.Fil: Poisson, Mariano. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Bustos, C.. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Lopez Fuentes, Marcelo Claudio. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Mandrini, Cristina Hemilse. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Cristiani, Germán Diego. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; Argentin

Morphology and DNA sequence data reveal the presence of Globodera ellingtonae in the Andean region

Potato cyst nematodes, G. rostochiensis and G. pallida, are the most economically important nematode pests of potatoes worldwide and are subject to strict quarantine regulations in many countries. Globodera ellingtonae was recently described from Oregon (USA), with its host-plant in the field being still unknown. Roots of Andean potatoes from the North of Argentina have been found attacked by this nematode, providing further evidence that this is a potato cyst nematode species, along with G. pallida and G. rostochiensis. New information about morphological, biological and molecular aspects of G. ellingtonae is provided for diagnostic purposes. The Argentine population showed morphological differences from specimens from Oregon; therefore, new diagnostic characters were defined to differentiate G. ellingtonae from its closest species. The Hsp90 gene was shown to be a good diagnostic marker for discriminating the three PCN species. The importance of the detection of G. ellingtonae on potatoes in the Andean region is not restricted to a regional level, since the nematode is also present in USA. This species can pose a serious problem to potato crop, especially when infected tubers are used as seeds. The distribution in the South American Andes is likely to extend the currently known distribution areas because cysts are passively transported. There is a need to evaluate the possible damage it may cause to potato crops. Morphological and molecular diagnoses conducted in this work provide fundamental information for the protection of potato crops not only in those countries in the Americas where the species has already been detected, but also worldwide.Fil: Lax, Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; ArgentinaFil: Rondan Dueñas, Juan. Provincia de Córdoba. Ministerio de Ciencia y Técnica. Centro de Excelencia En Productos y Procesos de Córdoba; ArgentinaFil: Franco Ponce, Javier. PROINPA Foundation; BoliviaFil: Gardenal, Cristina Noemi. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; ArgentinaFil: Doucet, Marcelo Edmundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Diversidad y Ecología Animal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto de Diversidad y Ecología Animal; Argentin

Analysis of a long-duration AR throughout five solar rotations: Magnetic properties and ejective events

Coronal mass ejections (CMEs), which are among the most magnificent solar eruptions, are a major driver of space weather and can thus affect diverse human technologies. Different processes have been proposed to explain the initiation and release of CMEs from solar active regions (ARs), without reaching consensus on which is the predominant scenario, and thus rendering impossible to accurately predict when a CME is going to erupt from a given AR. To investigate AR magnetic properties that favor CMEs production, we employ multi-spacecraft data to analyze a long duration AR (NOAA 11089, 11100, 11106, 11112 and 11121) throughout its complete lifetime, spanning five Carrington rotations from July to November 2010. We use data from the Solar Dynamics Observatory to study the evolution of the AR magnetic properties during the five near-side passages, and a proxy to follow the magnetic flux changes when no magnetograms are available, i.e. during far-side transits. The ejectivity is studied by characterizing the angular widths, speeds and masses of 108 CMEs that we associated to the AR, when examining a 124-day period. Such an ejectivity tracking was possible thanks to the multi-viewpoint images provided by the Solar-Terrestrial Relations Observatory and Solar and Heliospheric Observatory in a quasi-quadrature configuration. We also inspected the X-ray flares registered by the GOES satellite and found 162 to be associated to the AR under study. Given the substantial number of ejections studied, we use a statistical approach instead of a single-event analysis. We found three well defined periods of very high CMEs activity and two periods with no mass ejections that are preceded or accompanied by characteristic changes in the AR magnetic flux, free magnetic energy and/or presence of electric currents. Our large sample of CMEs and long term study of a single AR, provide further evidence relating AR magnetic activity to CME and Flare production.Fil: Iglesias, Francisco Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina. Universidad Tecnológica Nacional. Facultad Regional de Mendoza; ArgentinaFil: Cremades Fernandez, Maria Hebe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza; Argentina. Universidad Tecnológica Nacional. Facultad Regional de Mendoza; ArgentinaFil: Merenda, Luciano A.. Universidad Tecnológica Nacional. Facultad Regional de Mendoza; ArgentinaFil: Mandrini, Cristina Hemilse. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Lopez Fuentes, Marcelo Claudio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: Lopez Fuentes, Marcelo Claudio. Consejo Nacional de Investigaciónes Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Astronomía y Física del Espacio. - Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Astronomía y Física del Espacio; ArgentinaFil: Ugarte Urra, Ignacio. Spece Sciences División. Naval Research Laboratory; Estados Unido

Normativa y gestión del patrimonio paleontológico en municipios costeros de provincia de Buenos Aires, Rca. Argentina

Varios municipios costeros bonaerenses cuentan en su litoral con sitios de importancia paleontológica de orden nacional e internacional. Sus fósiles representan herramientas básicas para comprender los procesos geológicos, biológicos y ambientales del pasado. La erosión costera, las obras de protección litoral, el saqueo, el tránsito vehicular sobre médanos y playas y otras manifestaciones de la presión antrópica ponen en riesgo este patrimonio, sin que el marco legal resulte suficiente para el resguardo de dichos bienes. Los objetivos de este trabajo son: a) Relevar la normativa existente acerca de la preservación del registro y legado paleontológico y b) Proponer algunos lineamientos para mejorar su protección y gestión. El método exploró y describió el marco legal vigente. Los resultados obtenidos muestran vacíos en la temática.Several coastal municipalities of Buenos Aires province have sites of national and international importance. Their fossils are basic tools to understand the geological, biological and environmental processes of the past. Coastal erosion, construction of coastal protection, looting, vehicular traffic on sand dunes and beaches and other manifestations of the anthropic pressure threaten this heritage, without the legal framework is sufficient for safeguarding such property. The objectives guiding this work are: a) relieving the existing regulations regarding registration and preservation of paleontological heritage and b) To propose some guidelines to improve their protection and management. The method explored and described the current legal framework. The results show gaps in the subject.Fil: García, Mónica Cristina. Universidad Nacional de Mar del Plata. Facultad de Humanidades; Argentina.Fil: Veneziano, Marcelo Francisco. Universidad Nacional de Mar del Plata. Facultad de Humanidades; Argentina

Comportamiento temporal y tendencias climáticas en la ciudad de Mar del Plata (período 1971-2010)

Las condiciones climáticas de Mar del Plata, por su localización en el sudeste bonaerense, resultan representativas del clima templado con influencia oceánica. Los objetivos de esta investigación pretenden analizar el comportamiento temporal y tendencias de tres parámetros meteorológicos (temperatura, precipitación y viento) en el período 1971-2010; determinar sus condiciones típicas estacionales y verificar si existen evidencias de variabilidad climática. El método seguido para analizar climáticamente el área, consistió tanto en el análisis de sus valores medios como extremos mensuales, anuales y decenales, el procesamiento estadístico estándar de la información meteorológica y la determinación de variaciones temporales, oscilaciones y tendencias de los elementos climáticos considerados. Los principales resultados obtenidos ponen de manifiesto que el lapso 2001-2010 no muestra grandes variaciones respecto de los anteriores; no obstante, se observan diferencias en el monto anual y distribución estacional de precipitaciones y en la intensidad del viento, entre otros.The climatic conditions of Mar del Plata, by its location in the southeast of Buenos Aires, are representative of temperate climate with oceanic influences. The objectives of this research aim to analyze the temporal behavior and trends three meteorological parameters (temperature, precipitation and wind) in the period 1971-2010; determine its typical seasonal conditions and check for evidence of climate variability. The method used to analyze the area climatically consisted in the analysis of their mean values and extreme monthly, annual and decadal standard statistical processing of meteorological information and the determination of temporal variations, fluctuations and trends of climate elements considered. The main results show that the period 2001-2010 does not show large variations thereof; however, differences are observed in the annual amount and seasonal distribution of precipitation in the wind intensity, etc.Fil: García, Mónica Cristina. Universidad Nacional de Mar del Plata. Facultad de Humanidades; Argentina.Fil: Veneziano, Marcelo Francisco. Universidad Nacional de Mar del Plata. Facultad de Humanidades; Argentina