Caracterización mineralógica de las arcillas en la zona "Bajada a Valle Hermoso" de la Ruta Provincial E-57

La construcción de la RP E57, ha contribuido a una amplificación de la intensidad y la velocidad de los procesos geomorfológicos. Dando origen a caídas, deslizamientos y flujos de suelo y roca, así como los relacionados con la escorrentía superficial que produjeron represamiento del arroyo Vaquerías y, fenómenos que inciden directamente en la inestabilidad de las vertientes. Se ha planteado un estudio de detalle de la fracción de rango granulométrico de 2µm, asociado a una serie de sedimentos. El área de estudio se ubica en la porción central de la Sierra Chica, comprendida entre los meridianos 64° 41 y 64° 47 de longitud Oeste y paralelos 31° 10 y 31° 13 de latitud Sur, integrada en la cuenca del arroyo Vaquerías. Los minerales del grupo de la arcilla en la secuencia sedimentaria estudiada son heterogéneos generando por lo tanto comportamientos de colapso diferenciados, dependiendo esto de la abundancia y distribución de los minerales portante dejando indicado que los suelos son inestables debido a la presencia de minerales del grupo de la illita y kaolinita.Fil: Ayala, R. Universidad Nacional de Córdoba; Argentina.Fil: Cejas, G. Universidad Nacional de Córdoba; Argentina.Fil: Rubín, D. Universidad Nacional de Córdoba; Argentina.Fil: Paredes, R. Universidad Nacional de Córdoba; Argentina.Otras Ciencias de la Tierra y relacionadas con el Medio Ambient

Effects of photooxidation on membrane integrity in Salix nigra seeds

Background and Aims: Salix nigra seeds are desiccation-tolerant, as are orthodox seeds, although in contrast to other orthodox seeds they lose viability in a few weeks at room temperature. They also differ in that the chloroplasts of the embryo tissues conserve their chlorophyll and endomembranes. The aim of this paper was to investigate the role of chlorophyll in seed deterioration. Methods: Seeds were aged at different light intensities and atmospheric conditions. Mean germination time and normal and total germination were evaluated. The formation of free radicals was assessed using electronic spin resonance spectroscopy, and changes in the fatty acid composition from phospholipids, galactolipids and triglycerides using gas-liquid chromatography. Membrane integrity was studied with electronic spin resonance spin probe techniques, electrolyte leakage and transmission electron microscopy. Key Results: Light and oxygen played an important role in free-radical generation, causing a decrease in normal germination and an increase in mean germination time. Both indices were associated with a decrease in polyunsaturated fatty acids derived from membrane lipids as phospholipids and galactolipids. The detection of damage in thylakoid membranes and an increase in plasmalemma permeability were consistent with the decrease in both types of lipids. Triglycerides remained unchanged. Light-induced damage began in outermost tissues and spread inwards, decreasing normal germination. Conclusions: Salix nigra seeds were very susceptible to photooxidation. The thylakoid membranes appeared to be the first target of the photooxidative process since there were large decreases in galactolipids and both these lipids and the activated chlorophyll are contiguous in the structure of that membrane. Changes in normal germination and mean germination time could be explained by the deteriorative effects of oxidation.Instituto de Investigaciones Bioquímicas de La Plat

Formulación de un modelo de urbanización sustentable en la cuenca superior del Río Grande San Luis

En este trabajo se presenta una metodología de análisis y clasificación para la valoración de geopotencial de la Cuenca Superior del Río Grande, La Carolina, San Luis, Argentina. La información fue volcada en un mapa de geopotenciales. En la zona se establecieron 40 unidades de geopotencial, las que se transforman en 3 áreas de Calidad Ambiental, simplificando de esta manera la información ambiental y su representación gráfica en el mapa de geopotenciales de alteración para futuras urbanizaciones. Podemos inferir que las zonas con un 90% de riesgo potencial son tres, dos al oriente de la cuenca y una en el centro norte de la misma. La zona de alto riesgo al NE de la cuenca esta asociado a los Cerros Mellizos y Tomolasta. La zona de alto riesgo ubicada al NW, en la cuenca media alta se encuentra relacionada a la confluencia del los ríos Invernada y La Carolina, pudiendo determinar que la potencialidad de deslizamiento esta proporcionada en especial por a la baja resistencia al corte de las rocas (ocasionada por los lineamientos tectónicos). Las zonas con un 60% de riesgo potencial de deslizamientos se encuentran distribuidas en toda la cuenca, en especial las relacionadas con las vertientes de los Cerros. Estas unidades geopotenciales son un instrumento que sir ve como soporte para lograr que la normativa ambiental sea más ajustada a la realidad.Fil: Ayala, R. Universidad Nacional de Córdoba; Argentina.Fil: Cejas, G. Universidad Nacional de Córdoba; Argentina.Fil: Paredes, R. Universidad Nacional de Córdoba; Argentina.Fil: Dogliani, J. Universidad Nacional de Córdoba; Argentina.Fil: Rubín, D. Universidad Nacional de Córdoba; Argentina.Ciencias Medioambientales (los aspectos sociales van en 5.7 "Geografía Económica y Social

Perpendicular magnetic anisotropy in granular multilayers of CoPd alloyed nanoparticles

Under the terms of the Creative Commons Attribution license.-- et al.Co-Pd multilayers obtained by Pd capping of pre-deposited Co nanoparticles on amorphous alumina are systematically studied by means of high-resolution transmission electron microscopy, x-ray diffraction, extended x-ray absorption fine structure, SQUID-based magnetometry, and x-ray magnetic circular dichroism. The films are formed by COPD alloyed nanoparticles self-organized across the layers, with the interspace between the nanoparticles filled by the non-alloyed Pd metal. The nanoparticles show atomic arrangements compatible with short-range chemical order of L10 strucure type. The collective magnetic behavior is that of ferromagnetically coupled particles with perpendicular magnetic anisotropy, irrespective of the amount of deposited Pd. For increasing temperature three magnetic phases are identified: hard ferromagnetic with strong coercive field, soft-ferromagnetic as in an amorphous asperomagnet, and superparamagnetic. Increasing the amount of Pd in the system leads to both magnetic hardness increment and higher transition temperatures. Magnetic total moments of 1.77(4) μB and 0.45(4) μB are found at Co and Pd sites, respectively, where the orbital moment of Co, 0.40(2) μB, is high, while that of Pd is negligible. The effective magnetic anisotropy is the largest in the capping metal series (Pd, Pt, W, Cu, Ag, Au), which is attributed to the interparticle interaction between de nanoparticles, in addition to the intraparticle anisotropy arising from hybridization between the 3d-4d bands associated to the Co and Pd chemical arrangement in a L10 structure type.The financial support of the Spanish Ministerio de Economía MAT2014-53921-R and Aragonese DGA-IMANA E34 projects is acknowledged.Peer Reviewe

Structural and magnetic properties of granular CoPd multilayers

Multilayers of bimetallic CoPd alloyed and assembled nanoparticles, prepared by room temperature sequential sputtering deposition on amorphous alumina, were studied by means of high-resolution transmission electron microscopy, x-ray diffraction, SQUID-based magnetometry and x-ray magnetic circular dichroism. Alloying between Co and Pd in these nanoparticles gives rise to a high perpendicular magnetic anisotropy. Their magnetic properties are temperature dependent: at low temperature, the multilayers are ferromagnetic with a high coercive field; at intermediate temperature the behavior is of a soft-ferromagnet, and at higher temperature, the perpendicular magnetic anisotropy in the nanoparticles disappears. The magnetic orbital moment to spin moment ratio is enhanced compared with Co bare nanoparticles and Co fcc bulk.The financial support of the Spanish MINECO MAT2011-23791, MAT2014-53921-R and Aragonese DGA-IMANA E34 projects is acknowledged.Peer Reviewe

Programa de internacionalización de los productos de “Finca La Isla”.

Dentro del proyecto 3J04 “Inteligencia Cultural y Comercial para los Negocios Internacionales”, se realizó el programa de internacionalización de varios productos naturales de la empresa “Finca La Isla”. Estos van desde: Miel, Jengibre, Vainilla, Cúrcuma, Canela, entre otros. El proyecto se centró en la exportación de la miel en dos destinos: Alemania y Turquía, centrándose en las ferias Internacionales de la Anuga 2023, en Cologne, y Apimondia 2022 en Estambul. El proyecto nos llevó a crear un brochure, en donde se pueden encontrar diferentes aspectos económicos, culturales, sociales, políticos, y de mercado, para que el empresario tenga en cuenta todo antes de iniciar la inversión. Nos dividimos en dos equipos de trabajo, cada uno enfocado en un paísITESO, A.C

Effects of photooxidation on membrane integrity in Salix nigra seeds

Background and Aims: Salix nigra seeds are desiccation-tolerant, as are orthodox seeds, although in contrast to other orthodox seeds they lose viability in a few weeks at room temperature. They also differ in that the chloroplasts of the embryo tissues conserve their chlorophyll and endomembranes. The aim of this paper was to investigate the role of chlorophyll in seed deterioration. Methods: Seeds were aged at different light intensities and atmospheric conditions. Mean germination time and normal and total germination were evaluated. The formation of free radicals was assessed using electronic spin resonance spectroscopy, and changes in the fatty acid composition from phospholipids, galactolipids and triglycerides using gas-liquid chromatography. Membrane integrity was studied with electronic spin resonance spin probe techniques, electrolyte leakage and transmission electron microscopy. Key Results: Light and oxygen played an important role in free-radical generation, causing a decrease in normal germination and an increase in mean germination time. Both indices were associated with a decrease in polyunsaturated fatty acids derived from membrane lipids as phospholipids and galactolipids. The detection of damage in thylakoid membranes and an increase in plasmalemma permeability were consistent with the decrease in both types of lipids. Triglycerides remained unchanged. Light-induced damage began in outermost tissues and spread inwards, decreasing normal germination. Conclusions: Salix nigra seeds were very susceptible to photooxidation. The thylakoid membranes appeared to be the first target of the photooxidative process since there were large decreases in galactolipids and both these lipids and the activated chlorophyll are contiguous in the structure of that membrane. Changes in normal germination and mean germination time could be explained by the deteriorative effects of oxidation.Instituto de Investigaciones Bioquímicas de La Plat

Massless geodesics in AdS5×Y(p,q)AdS_5\times Y(p,q) as a superintegrable system

A Carter like constant for the geodesic motion in the $Y(p,q)$ Einstein-Sasaki geometries is presented. This constant is functionally independent with respect to the five known constants for the geometry. Since the geometry is five dimensional and the number of independent constants of motion is at least six, the geodesic equations are superintegrable. We point out that this result applies to the configuration of massless geodesic in $AdS_5\times Y(p,q)$ studied by Benvenuti and Kruczenski, which are matched to long BPS operators in the dual N=1 supersymmetric gauge theory.Comment: 20 pages, no figures. Small misprint is corrected in the Killing-Yano tensor. No change in any result or conclusion