Selective dissolved air flotation of fine mineral particles

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A proteomic approach acute and chronic phase of chagas disease

Comunicaciones a Congreso

Evolution of the Great Tehuelche Paleolake in the Torres del Paine National Park of Chilean Patagonia during the Last Glacial Maximum and Holocene

Indexación: Web of Science; ScieloRESUMEN. Una serie de morrenas glaciares se distribuyen desde el margen oriental de la cuenca de drenaje Torres del Paine a cerca del actual margen de los Campos de Hielo Patagónico, junto con una serie de terrazas lacustres regional continuos relacionados con las fluctuaciones glaciales. La geomorfología, apoyada por la evidencia de sedimentos del lago, indica la existencia de un único paleolago proglacial en esta zona, aquí denominado el Gran Tehuelche paleolago. Este concepto ayuda a aclarar la cronología de eventos glaciales y conduce a una mejor comprensión de la evolución del sistema hidrológico de la zona de Torres del Paine. Avances glaciales referidos anteriormente como ocurrieron A, B y C durante el Último Máximo Glacial y alimentados con la Gran Tehuelche paleolago con agua de deshielo, que le permite alcanzar su máxima extensión. El descubrimiento de trombolitos en Laguna Amarga sugiere que el drenaje de la paleolago hacia el fiordo de Última Esperanza tuvo lugar en 7113 Cal. años AP, después de la fusión de una barrera de hielo que existía durante el avance glacial antes. Esto dio lugar al desarrollo de un sistema hidrológico fluvio-lacustre complejo que persiste hasta nuestros días. Palabras clave: Patagonia, último máximo glacial, Younger Dryas, trombolitos. RESUMEN. Un grupo de morrenas glaciales estan Distribuidas desde el margen Este de la cuenca de drenaje de Torres del Paine Hacia el margen real de los Campos de Hielo Patagónicos. Las morrenas se observan en conjunto con las Naciones Unidas Grupo de terrazas Lacustres Regionales, las Cuales estan vinculadas y una las fluctuaciones glaciales. La geomorfología y Evidencias de sedimentos Lacustres indicano la existence De unico ONU lago proglacial, referido En Este Estudio de Como Gran Paleolago Tehuelche. Este Concepto ayuda a clarificar la cronología de los eventos glaciales y permite Una mejor Comprensión de la Evolución del Sistema hidrológico del sector de Torres del Paine. Los eventos glaciales, previamente Referidos Como Avance A, B y C, ocurrieron Durante el Último Máximo Glacial y alimentaron con Aguas de fusión al Gran Paleolago Tehuelche, permitiéndole Alcanzar su alcalde extensión. El Descubrimiento de trombolitos en Laguna Amarga sugiere Que El desagüe del paleolago Ocurrió Hace 7.113 Cal. Por años AP el Seno de Última Esperanza, producto de la fusión De Una barrera glaciar existente Durante los Avances glaciales Anteriores. LUEGO del drenaje sí Desarrollo en Un complejo Sistema hidrológico Que Persiste Hasta el presente. Palabras clave: Patagonia, Último Máximo Glacial, Dryas Temprano, Trombolitos.http://ref.scielo.org/wgc2q

Linear Processes in Stochastic Population Dynamics: Theory and Application to Insect Development

We consider stochastic population processes (Markov jump processes) that develop as a consequence of the occurrence of random events at random time intervals. The population is divided into subpopulations or compartments. The events occur at rates that depend linearly on the number of individuals in the different described compartments. The dynamics is presented in terms of Kolmogorov Forward Equation in the space of events and projected onto the space of populations when needed. The general properties of the problem are discussed. Solutions are obtained using a revised version of the Method of Characteristics. After a few examples of exact solutions we systematically develop short-time approximations to the problem. While the lowest order approximation matches the Poisson and multinomial heuristics previously proposed, higher-order approximations are completely new. Further, we analyse a model for insect development as a sequence of developmental stages regulated by rates that are linear in the implied subpopulations. Transition to the next stage competes with death at all times. The process ends at a predetermined stage, for example, pupation or adult emergence. In its simpler version all the stages are distributed with the same characteristic time.Fil: Solari, Hernan Gustavo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Natiello, Mario A.. Lund University; Sueci

On the persistence of the ether as absolute space

We present a novel -- fully relational -- definition of inertial systems based in the No Arbitrariness Principle, that eliminates the need for absolute inertial frames of reference in order to formulate Newtonian mechanics. This approach allows for a class of inertial systems larger than what traditionally comes out of the equivalence principle. We begin by discussing the relevance of the phenomenological map in order to relate observations and predicted observations with the mathematical structure of physical theories. After revisiting the concept of inertial frames in Classical Mechanics, we attempt to identify the phenomenological map of Special Relativity (SR) in order to establish its contact points with Classical Mechanics. SR actually inherits Lorentz' use of the ether, developed in his interpretation of Maxwell's electrodynamics. In summary, velocities in the Lorentz transformations must be \textcolor{black}{expressed from a distinguished reference frame}\textcolor{brown}{{} }if the theory is not to fall apart for being inconsistent. The consistency problem is not in the exposed part of the theory but in the supporting phenomenological map which, rather than being constructed anew, it transports concepts of Classical Mechanics by habit, without revising their validity in the context of SR.Comment: 19 pages, 1 figur

Valoración de la calidad y fragilidad visual del paisaje

The physical characteristics of landscape can be identified by their visual attributes, since the planning, thedecisions of handling, the natural interaction of the culture and processes take to physical changes that will be seen inthe future in the landscape. The scenic landscapes are one of the majors sources for the human enjoyment and in somecases it has been the object of direct criminal action to conserve his quality. In addition, the necessity to count with validresources to quantify the scenic characters of the landscapes has increased substantially with the development of theplanning of the use of the earth and its requirements of environmental data in which to base the decisions of earth use.A methodology for the valuation of the Visual Quality and its Fragility appears, as much of the rural landscapes as of theurban ones, with the purpose of having a valuation of the landscape that allows to order of suitable form the implantationof certain uses and activities in a territoryLas características físicas del paisaje pueden ser identificadas por sus atributos visuales, yaque el planeamiento, las decisiones de manejo, la interacción de la cultura y los procesos naturales llevan a cambios físicos que se verán en el futuro en el paisaje. Los paisajes escénicos son una de las mayores fuentes para el goce humano y en algunos casos ha sido el objeto de acción pública directa paraconservar su calidad. Además, la necesidad de contar con medios válidos por cuantificar los caracteresescénicos de los paisajes ha aumentado substancialmente con el desarrollo de la planificación del usode la tierra y sus requisitos de datos medioambientales en que basar las decisiones de uso de tierra. Sepresenta una metodología para la valoración de la Calidad Visual y su Fragilidad, tanto de los paisajesrurales como de los urbanos, con el fin de disponer de una valoración del paisaje que permita ordenarde forma adecuada la implantación de determinados usos y actividades en un territorio.As características físicas da paisagem podem ser identificadas por seus atributos visuais, já que o planejamento,as decisões de manejo, a interação da cultura e os processos naturais levam a mudanças físicas que se verão no futuro napaisagem. As paisagens cênicas são uma das maiores fontes para o goze humano e em alguns casos foi o objeto de açãopública direta para conservar sua qualidade. Alem disso, a necessidade de contar com meios válidos para quantificar oscarateres cênicos das paisagens aumentou substancialmente com o desenvolvimento do planejamento do uso da terra eseus requisitos de dados meio ambientais em que basear as decisões de uso da terra. Apresenta-se uma metodologia paraa valoração da Qualidade Visual e sua Fragilidade, tanto das paisagens rurais como dos urbanos, com o fim de dispor deuma valoração da paisagem que permita ordenar de maneira adequada a implantação de determinados usos e atividadesnum território

The annual rate of independent events - A key interpretation for traditional extreme value distributions of wind velocity

The extreme value theory has been object of engineering studies for more than a century. The analysis of extreme winds plays a key role for complex civil structures and a driving role in different stages of wind turbines lifetime. Most of extremes probability models depend on the annual rate of independent events (ARIE) which has been traditionally considered a constant value. The authors have embraced a recent belief considering the ARIE as a function of the wind velocity. Even though a certain agreement has been achieved across the researches, some issues are still pending. In this regard, the paper shows that the annual, seasonal and daily fluctuations embedded in time series of the mean wind speeds, constrain its probability distribution and time correlation to be physically consistent. Besides, a new physical interpretation of the ARIE is presented, expressing how the independence across wind observations increases with the wind speed, up to the point that all yearly observations are independent if larger than a suitable speed value. Such a tendency is not revealed if the annual, seasonal and daily fluctuations are excluded by the analysis, leading to a deceitful shape of the ARIE. Finally, the paper shows how the velocity-dependent ARIE model is consistent with the conventional asymptotic extreme value theory, if a sufficiently large left-censorship applies to the dataset. The study of the ARIE presented in this paper is based on long-term Monte Carlo simulation of the mean wind speed

Dinámica de formas inorgánicas de nitrógeno en suelos inundados en la cuenca del Río Salado : experiencia in situ

Fil: Kuaíni, Karina. Instituto de Limnología Dr. R. Ringuelet, (ILPLA), CONICET-UNLP. Florencio Varela, ArgentinaFil: Gabellone, Néstor A.. Instituto de Limnología Dr. R. Ringuelet, (ILPLA), CONICET-UNLP. Florencio Varela, ArgentinaFil: Solari, Lía Cristina. Instituto de Limnología Dr. R. Ringuelet, (ILPLA), CONICET-UNLP. Florencio Varela, Argentin