Applications of almgren-pitts min-max theory

We develop an application of Almgren-Pitts min-max theory to the study of minimal hypersurfaces in dimension 3 ≤ m + 1 ≤ 7 as well as computing the k-width of the round 2-sphere for k = 1,...,8. We show that the space of minimal hypersurfaces is non-compact for an analytic metric of positive curvature and construct a min-max unstable closed geodesic in S^2 with multiplicity 2.Open Acces

Inventario de avifauna del norte de Entre Ríos, Argentina: registros notables y perspectivas de conservación

Biodiversity inventories remain fundamental tools for biodiversity conservation. Neotropical biota has poor faunal inventories. In Argentina, the avifauna of the province of Entre Ríos is still not well known. Here, we present the first exhaustive bird inventory of Northern Entre Ríos. We recorded 317 bird species. Three species were new for the province of Entre Ríos and eight were new for Northern Entre Ríos. We recorded 17 threatened species, 4 biome-restricted species and two restricted range species. The high bird diversity of Northern Entre Ríos contrasts with the lack of effective reserves to ensure the survival of endangered species. Creation of natural reserves in this area is urgent. These protected areas should have a management plan and stable park rangers assigned, to ensure the protection of the avian diversity of Northern Entre Ríos.Los inventarios de Biodiversidad siguen siendo herramientas fundamentales para la conservación de la biodiversidad. La biota neotropical posee inventarios incompletos de fauna. En Argentina, la avifauna de la provincia de Entre Ríos permanece poco estudiada. Presentamos el primer inventario exhaustivo de aves para el norte de Entre Ríos. Registramos 317 especies de aves, tres son nuevas para la provincia de Entre Ríos y ocho son nuevas para el norte de Entre Ríos. Diecisiete especies están consideradas amenazadas, 4 son especies restringidas a un bioma y dos especies son de rango restringido. La alta diversidad de aves del norte de Entre Ríos contrasta con la falta de reservas efectivas que puedan asegurar la supervivencia de las especies amenazadas. La creación de reservas naturales en esta región es urgente. Estas áreas protegidas deberían tener planes de manejo y guardaparques estables asignados, para asegurar la protección de la diversidad de aves del norte de Entre Ríos.Fil: Dardanelli, Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Norte. Estación Experimental Agropecuaria Delta del Paraná; ArgentinaFil: Reales, César Fabricio. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; ArgentinaFil: Sarquis, Juan Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; Argentin

Gold Sterile Ore Acid Generation Evaluation, San Juan Argentina

One of the problems that mining represents in relation to the natural watercourses is the possible formation of what we call acid mine drainage, which consists in the emission or formation of water effluents of great acidity, usually rich in sulfate and with variable contents in heavy metals. The drainage mentioned is developed from the metal sulfide and sulfate leaching. Researches about the creation of acid drainage suggest that the formation of these depends directly on various factors: primary mineralogy (neutralizer sulfides and minerals), water presence (whether), oxygen diffusion, grain size, microbiological interaction (bacterium), among others. To study these variables and to relate them with geological factors, static (Acid-Base Accounting) and dynamic (Humidity Cell) tests have been developed, among others. The mentioned tests are applied to a case of a gold deposit situated in the Province of San Juan, which is currently very argued because of its mining activity due to its leaching process. In the sterile mineral obtained from the process, kinetics tests were carried out in humidity cells to simulate the natural oxidation of the primary mineral samples. In the obtained leaching, pH values closer to neutrality and a limited solution metal presence were detected, indicating the neutralization ability due to the carbonates ores presence.Fil: Bazan Brizuela, Vanesa Lucia. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Investigaciones Mineras; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Sarquis, Pedro Edgardo. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Investigaciones Mineras; ArgentinaFil: Brandaleze, Elena. Universidad Tecnológica Nacional. Facultad Regional San Nicolás; Argentin

Ecological and Evolutionary Interactions Between Song Sparrows (Melospiza melodia) and their Bloodborne Parasites

Local adaptation is the result of natural selection operating at a local scale, such that trade-offs in fitness across different environments result in individuals having higher fitness in their place of origin than when transported into a foreign environment. Populations may become locally adapted to features of their abiotic environment, or in the case of coevolutionary arms races between hosts and parasites, to other species comprising their biotic environment. If host populations are adapted to their local (sympatric) parasites, or conversely if parasites are adapted to their local hosts, then interactions with local parasite strains may influence the fitness consequences of host dispersal. I investigated the ecological and evolutionary impact of haematozoan parasites (genera Plasmodium, Leucocytozoon, Haemoproteus) on song sparrow (Melospiza melodia) hosts. I hypothesized that song sparrows have an advantage in defending against local parasite strains, resulting in parasite-mediated selection against natal dispersal. I predicted that condition and survivorship should correlate positively with philopatry, and that such \u27home-field advantage\u27 is mediated by enhanced ability to deal with sympatric parasites. I used genetic assignment tests to quantify natural variation in philopatry, and asked whether song sparrows of local origin showed a home-field advantage over immigrants, across multiple populations (Chapter 2). I compared population genetic structure of hosts and parasites to test for coevolution (Chapter 3). I attempted to experimentally reduce parasite load, to test if malarial parasites decrease territorial defense (Chapter 4). Finally, I used a cross-infection design to compare resistance to sympatric versus allopatric strains of Plasmodium (Chapter 5). Song sparrows of local origin tended to have lower parasite loads in the wild. Moreover, sparrows were less likely to become infected when experimentally inoculated with a sympatric than an allopatric Plasmodium lineage. Population genetic structure of song sparrows was generally not correlated to that of parasites, but I found similar genetic structuring between song sparrows and one Plasmodium taxon. Interactions with haematozoan parasites may influence the fitness consequences of dispersal by song sparrows. This has implications for the evolution of dispersal, patterns of biodiversity, and conservation in an era of emerging infectious disease

El debate en la arquitectura : la construcción después del trauma

Fil: Sarquis, Jorge. Universidad de Buenos Aires. Facultad de Arquitectura. Programa de Actualización Proyectual de la Escuela de Posgrado; Argentina.Los atentados a las ciudades de Madrid y Nueva York han abierto un profundo debate entre\narquitectos y urbanistas: ¿Hay que construir para prevenir la eventualidad de un ataque? ¿Hay que\ndiseñar espacios que disimulen la amenaza para no atemorizar a los habitantes? ¿Los nuevos\nespacios deben asumir un futuro inseguro o seguir diseñando con la idea de un mundo mejor que el\nactual? El fuerte cuestionamiento disciplinar se tornó público a partir de los proyectos urbanísticos para\nel Ground Zero, que reemplazarán a las destruidas Torres Gemelas. Las discusiones abiertas están en\npleno desarrollo. De sus conclusiones dependerán los lugares en los que todos viviremos: o\ncelebrarán la vida o nos prepararán para la muerte

Argentinean copper concentrates: structural aspects and thermal behaviour

In Argentina, there are many sources of copper concentrates. Some of them are currently in operation, while others are in the exploration stage. All copper concentrates produced are exported to other countries for copper refinement and to create various finished products. It is desirable that in the near future, these copper concentrates be processed in an Argentinean industrial plant. The aim of this paper was to present the results of a characterisation study carried out on five different copper concentrate samples. The thermal decomposition of the copper concentrates was determined by differential thermal analysis and thermogravimetry (DTA TG). The information was correlated with the chemical composition and the mineralogical phases of the samples identified by X-ray diffraction. A melting test at temperatures of up to 1300˚C was performed to complete the study of the concentrate’s behaviour during heating. After the test, all of the samples were observed by light and electronic scanning microscopy to identify the different phases generated under high-temperature conditions.Fil: Bazan Brizuela, Vanesa Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan; ArgentinaFil: Brandaleze, Elena. Universidad Tecnológica Nacional. Facultad Regional San Nicolás. Centro para el Desarrollo Tecnológico de Materiales; ArgentinaFil: Santini, Leandro Matias. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Tecnológica Nacional. Facultad Regional San Nicolás. Centro para el Desarrollo Tecnológico de Materiales; ArgentinaFil: Sarquis, Pedro Edgardo. Universidad Nacional de San Juan; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Business cycles in a credit constrained small open economy.

This thesis addresses the sources and propagation mechanisms of business cycles in small open emerging economies. Vector autoregressive analyses (Chapter 1) of Brazil - whose regularities are common to other emerging economies - show that exogenous global credit disturbances affecting international liquidity, uncertainty and risk appetite account for over 40% of output variability. These disturbances explain the bulk of emerging economies' excess macroeconomic volatility. They transmit via credit frictions, mainly as shocks to the real interest rates that emerging economies face in international markets. They comprise about 60% of the country spread variations. Responses of output and other real aggregates to credit shocks reveal growth persistence, hump-shaped recession and recovery patterns. These regularities are examined within proposed dynamic stochastic general equilibrium models of a small open economy with permanently binding endogenous constraint on foreign credit. When accumulating capital works as collateral in the constraint, the model (Chapter 2) exhibits unprecedented intertemporal propagation, mainly through wedges between consumption's marginal rate of substitution and the return on capital. Interest rate shocks have significant persistent effects which mitigate the dominance of uncorrelated productivity shocks. The model nests properties of real business cycle models and overcomes typical anomalies of small open economy models which are derived from weak consumption substitution effects. A second model (Chapter 3) tackles the macroeconomic implications of country spread as an endogenous state variable affecting credit and business cycles. The spread is built into an endogenous credit constraint, similar to an external financial premium. Amplification and propagation mechanisms are further enhanced through an enriched intertemporal wedge. Independent US real interest rate and exogenous country spread shocks - representing exogenous credit disturbances to emerging economies - are equally important over business cycle horizons. Calibrated for Brazil, both models match qualitative and quantitative regularities empirically observed in response dynamics, second moments and variance decompositions