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Sample records for plata caracterizacion geologica

  1. Visits to La Plata Observatory

    Science.gov (United States)

    Feinstein, A.

    1985-03-01

    La Plata Observatory will welcome visitors to ESO-La Silla that are willing to make a stop at Buenos Aires on their trip to Chile or on their way back. There is a nice guesthouse at the Observatory that can be used, for a couple of days or so, by astronomers interested in visiting the Observatory and delivering talks on their research work to the Argentine colleagues. No payments can, however, be made at present. La Plata is at 60 km from Buenos Aires. In the same area lie the Instituto de Astronomia y Fisica dei Espacio (IAFE), in Buenos Aires proper, and the Instituto Argentino de Radioastronomia (IAR). about 40 km from Buenos Aires on the way to La Plata. Those interested should contacl: Sr Decano Prof. Cesar A. Mondinalli, or Dr Alejandro Feinstein, Observatorio Astron6mico, Paseo dei Bosque, 1900 La Plata, Argentina. Telex: 31216 CESLA AR.

  2. La nuova Carta Geologica d’Italia alla scala 1:1.250.000

    Directory of Open Access Journals (Sweden)

    Marco Pantaloni

    2007-03-01

    Full Text Available Una carta così concepita ha come scopo quello di diffondere in ambito scientifico ma anche, e soprattutto, in ambito didattico, la conoscenza geologica del territorio. L’obiettivo che l’APAT si è impegnato a raggiungere tramite di essa è infatti quello di far arrivare ad un pubblico molto ampio di studiosi, di insegnanti, di studenti e di appassionati, una sintesi delle conoscenze finora raccolte nell’ambito della più recente realizzazione cartografica, la già citata carta geologica alla scala 1:50.000. L’ultima, in ordine di tempo, delle carte a piccola scala realizzate dal Servizio Geologico d’Italia è rappresentata dalla Carta Geologica a scala 1:500.000 pubblicata in 5 fogli durante il periodo 1976-1983.

  3. Pumping systems characterization; Caracterizacion de los sistemas de bombeo

    Energy Technology Data Exchange (ETDEWEB)

    Torres Gutierrez, R. [Eficiencia Energetica, S.A. de C.V., Mexico, D. F. (Mexico)

    1995-12-31

    In this paper the characterization of the pumping systems is discussed, and an explanation is given of the need of evaluating in detail the possibility of implementing the frequency variators as an option for energy conservation, explaining how the simple use of the similarity or affinity laws lead to over-estimate the saving. [Espanol] En este articulo se describe la caracterizacion de los sistemas de bombeo y se explica la necesidad de evaluar en detalle la posibilidad de implementacion de variadores de frecuencia, como una alternativa para el ahorro de energia, explicando como el simple uso de las leyes de semejanza o afinidad llevan a sobre-evaluar los ahorros.

  4. Pumping systems characterization; Caracterizacion de los sistemas de bombeo

    Energy Technology Data Exchange (ETDEWEB)

    Torres Gutierrez, R [Eficiencia Energetica, S.A. de C.V., Mexico, D. F. (Mexico)

    1996-12-31

    In this paper the characterization of the pumping systems is discussed, and an explanation is given of the need of evaluating in detail the possibility of implementing the frequency variators as an option for energy conservation, explaining how the simple use of the similarity or affinity laws lead to over-estimate the saving. [Espanol] En este articulo se describe la caracterizacion de los sistemas de bombeo y se explica la necesidad de evaluar en detalle la posibilidad de implementacion de variadores de frecuencia, como una alternativa para el ahorro de energia, explicando como el simple uso de las leyes de semejanza o afinidad llevan a sobre-evaluar los ahorros.

  5. Benthic survey of natural and artificial reefs off Mar del Plata, Argentina, southwestern Atlantic Estudios del bentos de arrecifes naturales y artificiales de Mar del Plata, Argentina, Atlántico sudoccidental

    Directory of Open Access Journals (Sweden)

    Gabriel Genzano

    2011-11-01

    . Las caracterizaciones topográficas y los censos de invertebrados y peces se realizaron mediante buceo autónomo en noviembre y diciembre de 2005. Los datos ambientales y biológicos fueron analizados mediante análisis multivariados no paramétricos. Los arrecifes fueron principalmente discriminados acorde a su profundidad y posición del sustrato. El alga roja calcárea Corallina officinalis fue dominante en los NR poco profundos, mientras que conspicuas asociaciones del mitílido Mytilus platensis se encontraron a más de 3 m de profundidad; la anémona de mar Anthothoe chilensis fue más abundante a los 6-10 m y el coral blando Tripalea clavaria cerca de los 20 m de profundidad. No se evidenciaron diferencias entre los ARs de disposición horizontal y los NR aledaños. Las mayores diferencias fueron halladas en las comunidades de los sustratos verticales vs horizontales tanto en NRs y ARs. Se registraron 15 especies de peces. Aquellas con fuerte fidelidad por el habitat, e.g. Acanthistius brasilianus y Pseudopercis semifasciata, fueron claramente más abundantes y/o frecuentes en los ARs (pecios en comparación con los NRs. Este estudio pionero en el área mostró que los arrecifes permiten la fijación de diversas asociaciones bentónicas. Los ARs aportan además refugio para los peces. Debido a que la pesca recreacional y el buceo son actividades que se están desarrollando en Mar del Plata, donde el turismo es uno de los principales recursos económicos, la protección de estas áreas debería considerarse en los planes de conservación.

  6. Teaching Humanities at the National University of la Plata, Argentina.

    Science.gov (United States)

    Acuña, Leopoldo E

    2003-10-01

    In this article the author begins by giving a brief history of medical education in Argentina, then provides some background information on the National University of La Plata. He describes two major initiatives at La Plata: a new and pioneering admission policy (implemented in 1993) and a change in the number of hours and years in the curriculum. He then looks back to the introduction in 1976 of La Plata's medical humanities program. Over its 20 year existence, the program has undergone a number of changes in response both to students' interests and financial concerns. The revised humanities curriculum now consists of four elective courses: medicine and literature, anthropology, history of medicine, and "medical kalology" (which focuses on music and dance). Unfortunately, the program, while it has been well received by both students and faculty and has inspired programs at other Argentinean schools, is threatened by Argentina's economic crisis.

  7. Construcción de electrodos de plata / cloruro de plata para medición de potenciales eléctricos en estructuras sumergidas

    OpenAIRE

    Alejandro David, Agama Mosquera; Peña Estrella, Julián

    2013-01-01

    En este proyecto se logró construir en el laboratorio de materiales un electrodo experimental plata/cloruro de plata para medición de potenciales eléctricos en estructuras sumergidas. Utilizando un procedimiento experimental llamado electrolisis se formo sobre el electrodo, específicamente en la rejilla del electrodo experimental una capa fina de cloruro de plata. A continuación se realizó los cálculos pertinentes de la masa de cloruro de plata que se formo durante el proceso de electrolisis ...

  8. Evaluation of sand reserves in del Plata City

    International Nuclear Information System (INIS)

    Loureiro, J.

    2014-01-01

    The purpose of this study is to evaluate the reserve of sand in the zone of del Plata city and beyond. This area is located in the S E edge of the department of San Jose near the mouth of Santa Lucia river. In this zone was identified the mantle of potentially exploitable sand which are based on their particle size, composition and depth of the limits cape. There are two powerful capes of sand separated by clay and silt

  9. Sedimentation Survey of Lago La Plata, Puerto Rico, July 2006

    Science.gov (United States)

    Soler-López, Luis R.

    2008-01-01

    Lago La Plata dam is located between the municipalities of Naranjito and Toa Alta in north central Puerto Rico, about 5 kilometers south of the town of Toa Alta and about 5 kilometers north of the town of Naranjito. The reservoir impounds the waters of the Rio de La Plata, the Rio Guadiana, and the Rio Ca?as, and is part of the San Juan Metropolitan Water District, which provides about 35 percent of the total water demand for the area (Soler-Lopez and others, 2000). The reservoir has a drainage area of about 469 square kilometers. The dam was constructed in 1974 and is a concrete gravity structure with a normal pool elevation of 52.00 meters above mean sea level (Puerto Rico Electric Power Authority, 1979). During October 1998, the U.S. Geological Survey (USGS), Caribbean Water Science Center, in cooperation with the Puerto Rico Aqueduct and Sewer Authority (PRASA) conducted a bathymetric survey of Lago La Plata to assess the impact of Hurricane Georges on the storage capacity of the reservoir. Between July 17 and 20, 2006, the USGS and the PRASA conducted an additional bathymetric survey of Lago La Plata to update the reservoir storage capacity and determine the reservoir sedimentation rate by comparing the 2006 survey data with the 1998 survey data.. The purpose of this report is to update the reservoir storage capacity, sedimentation rates, and areas of substantial sediment accumulation since 1998. Historical (1974) data are referenced as needed to account for long-term storage capacity loss trends...

  10. Recent La Plata basin drought conditions observed by satellite gravimetry

    OpenAIRE

    L. Chen , J.; R. Wilson , C.; D. Tapley , B.; Longuevergne , L.; L. Yang , Z.; R. Scanlon , B.

    2010-01-01

    International audience; The Gravity Recovery and Climate Experiment (GRACE) provides quantitative measures of terrestrial water storage (TWS) change. GRACE data show a significant decrease in TWS in the lower (southern) La Plata river basin of South America over the period 2002-2009, consistent with recognized drought conditions in the region. GRACE data reveal a detailed picture of temporal and spatial evolution of this severe drought event, which suggests that the drought began in lower La ...

  11. Superficial characterization by XP S of silver nanoparticles and their hydrothermal deposit over zircaloy; Caracterizacion superficial por XPS de nanoparticulas de plata y su deposito hidrotermal sobre zircaloy

    Energy Technology Data Exchange (ETDEWEB)

    Contreras R, A.; Gutierrez W, C.; Martinez M, I.; Medina A, A. L., E-mail: aida.contreras@inin.gob.mx [ININ, Departamento de Tecnologia de Materiales, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2012-10-15

    The analysis technique of X-ray photoelectron spectroscopy (XP S) is sensitive exclusively to the first layers of the solids surface, which allows obtaining information about the chemical, physical and electronic properties of them. The combustible elements of the boiling water nuclear reactors (BWR) are formed by zircaloy pipes that contain in their interior pellets or uranium dioxide. In this work is studied the zircaloy surface, oxidized zircaloy under similar conditions to those of a reactor BWR type and oxidized zircaloy with a hydrothermal deposit of silver nanoparticles and zinc. The silver deposit is a proposal of the Materials Technology Department of the Instituto Nacional de Investigaciones Nucleares (ININ) in Mexico, which has the same objective that the noble metals deposit (Pt, Pd, and Rh) that is practiced in some of the reactors BWR, in order to mitigating the speed of crack growth for IGSCC in stainless steels 304 Ss. (Author)

  12. Characterization of Hospital Residuals; Caracterizacion de Residuos Hospitalarios

    Energy Technology Data Exchange (ETDEWEB)

    Blanco Meza, A; Bonilla Jimenez, S

    1997-07-01

    The main objective of this investigation is the characterization of the solid residuals. A description of the handling of the liquid and gassy waste generated in hospitals is also given, identifying the source where they originate. To achieve the proposed objective the work was divided in three stages: The first one was the planning and the coordination with each hospital center, in this way, to determine the schedule of gathering of the waste can be possible. In the second stage a fieldwork was made; it consisted in gathering the quantitative and qualitative information of the general state of the handling of residuals. In the third and last stage, the information previously obtained was organized to express the results as the production rate per day by bed, generation of solid residuals for sampled services, type of solid residuals and density of the same ones. With the obtained results, approaches are settled down to either determine design parameters for final disposition whether for incineration, trituration, sanitary filler or recycling of some materials, and storage politics of the solid residuals that allow to determine the gathering frequency. The study concludes that it is necessary to improve the conditions of the residuals handling in some aspects, to provide the cleaning personnel of the equipment for gathering disposition and of security, minimum to carry out this work efficiently, and to maintain a control of all the dangerous waste, like sharp or polluted materials. In this way, an appreciable reduction is guaranteed in the impact on the atmosphere. (Author) [Spanish] El objetivo principal de esta investigacion es la caracterizacion de los residuos solidos. Se da tambien una descripcion del manejo de los desechos liquidos y gaseosos generados en hospitales, identificando la fuente donde se originan. Para lograr el objetivo propuesto se dividio el trabajo en tres etapas; la primera fue el planeamiento y la coordinacion con cada centro hospitalario

  13. Determinantes de la morosidad tributaria en Mar del Plata

    OpenAIRE

    Mallo, Paulino E.; Artola, María Antonia; Zanfrillo, Alicia Inés; Morettini, Mariano; Galante, Marcelo Javier; Pascual, Mariano Enrique; Busetto, Adrián Raúl

    2011-01-01

    El objetivo del artículo es analizar, a través de la aplicación de lógica difusa y de herramientas estadísticas, el comportamiento de los indicadores contables de las PyMEs marplatenses, ya que los mismos pueden incidir en la determinación de la morosidad en el pago de tributos nacionales, provinciales o municipales. Para ello, se trabaja con una muestra de empresas representativas de distintos sectores productivos de la ciudad de Mar del Plata, que incluye organizaciones de distinto tamaño y...

  14. Transformaciones territoriales en el periurbano de Mar del Plata

    Directory of Open Access Journals (Sweden)

    Laura Zulaica

    2012-01-01

    Full Text Available El estudio de las transformaciones territoriales de las áreas periurbanas demanda el conocimiento de la evolución de las actividades que allí se desarrollan. El presente trabajo analiza las transformaciones del periurbano de Mar del Plata entre los noventa y la actualidad, enfatizando en los cambios de las actividades. Para ello, se realiza una clasificación supervisada de usos sobre imágenes satelitales de 1989 y 2009, que es ajustada a partir de una base de datos del área. Posteriormente, se analizan las transformaciones considerando distintas fases de estructuración de las ciudades y se establece una periodización siguiendo las nociones de régimen y ruptura. El estudio realizado constituye una base para generar estrategias de ocupación y desarrollo del área y la metodología aplicada puede extenderse a otros territorios

  15. Los torques de plata de Monasterio de Rodilla

    Directory of Open Access Journals (Sweden)

    Castillo, Belén

    1996-12-01

    Full Text Available The silver torques coming from Monasterio de Rodilla (Burgos are an excepcional ensemble of the jewellery before Roman times in the northern Meseta. These pieces, wrought of rolled up braiding wires, belong to a fully-developed process in which the Iberian and Mediterranean influences become transformed by the local style and give rise to special and typical models of the Celtiberic jewellery.Los torques de plata procedentes de Monasterio de Rodilla (Burgos constituyen un conjunto excepcional de la orfebrería prerromana de la Meseta Norte. Estas piezas, elaboradas con alambres trenzados y enrollados, responden a un proceso evolucionado en el que las influencias ibéricas y mediterráneas, transformadas por el gusto local, dan lugar a modelos propios y característicos de la orfebrería celtibérica.

  16. Prototype study of characterization of the impact that produces the diffuser of an industrial discharge into the sea water; Estudio prototipo de caracterizacion del impacto que produce el difusor de una descarga industrial sobre el medio marino

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz Gallarza, S. M.; Gil Zurita, A.; Garcia Hernandez, R.; Vergara Mendez, S.; Garcia Leal, M. L. [Universidad Autonoma Metropolitana, Mexico, D.F. (Mexico)

    2000-09-01

    impact. [Spanish] Para establecer limites maximos permisibles de contaminantes descargados en el mar por vertimientos antropogenicos, las autoridades involucradas en la proteccion y reglamentacion ambiental han fijado caracteristicas particulares de descarga a cada empresa. Ademas de cuidar que no se excedan los niveles establecidos, debe evaluarse el efecto de estas sustancias sobre el medio. En este contexto, se realizan estudios interdisciplinarios integrales de caracterizacion del impacto en el medio marino a causa de las industrias. Una de ellas, la cual vierte al litoral noroeste del golfo de Mexico mediante un difusor submarino, solicito un primer estudio de este genero. En este estudio prototipo se efectuaron estimaciones fisicas, quimicas, biologicas y geologicas en una red de 49 estaciones en seis transectos posicionados a bordo de una embarcacion y con teodolitos desde la costa a cinco niveles (superficie, 4, 8, 12 y 16 m de profundidad) y durante lluvias, secas y nortes. Se determinaron metales pesados en agua, sedimentos, organismos y muestras combinadas de la descarga. Se relacionaron mediciones continuas de corrientes, salinidad y temperatura en las boquillas del difusor a partir de registros de dos corrientimetros S4 InterOcean. Con vuelos en helicopteros se registraron las variaciones de desplazamiento de la pluma de contaminantes en diversas condiciones climaticas. Se adquirieron imagenes del satelite LANDSAT TM para obtener informacion de diferentes regiones del espectro electromagnetico y para corroborar observaciones sobre el comportamiento de la pluma de descarga. Ademas de los metodos convencionales para graficacion y manejo de la informacion, se empleo visualizacion tridimensional, la cual permitio interpretar patrones estacionales y de difusion. Por los excelentes resultados obtenidos con esta metodologia, se presenta a la consideracion de los especialistas este estudio como un prototipo para la determinacion de impacto en ambientes marinos

  17. Human toxocarosis. Its seroprevalence in the City of La Plata

    Directory of Open Access Journals (Sweden)

    NE Radman

    2000-06-01

    Full Text Available Toxocara canis is very common in dogs throughout the world. It is the primary cause of visceral larva migrans (VLM in humans. Soil contaminated with T. canis embryonated eggs is the main source of infection of man. Our objective was to describe Toxocara seroprevalence in humans in the city of La Plata associated with some determinants such asage, presence or absence of clinical manifestations and risk factors. Blood samples were collected at random from 156 patients of different sex and age, with and without clinical symptoms compatible with the disease. The diagnostic technique ELISA test was performed with the Bordier Affinity Products Commercial Kit, using excretory-secretory Toxocara antigen with a sensitivity higher than 90%. The values were positive in 39% of the studied population. In the analysis according to age, the younger group presented significant differences with respect to the older one (Chi-square p<0.05. Positive patients presented clinical symptoms compatible with the disease (84%, and 41% presented some risk factor. The level of positivity obtained indicates a certain risk of being infectes mainly in patients younger than 15 years old. The authors agree that an early identification and treatment of VLM may save a life.

  18. Commentary of Uruguay geological structure - Present status of its mining activity; Comentarios sobre conformacion geologica del Uruguay - Estado actual de su actividad minera

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1988-07-01

    This work is about the geological structure of Uruguay and its mining activity. The Rio de la Plata socket basin and the Rivera crystalline island are the oldest geochronological structures in Uruguay. This unit represents the 60% of the crystalline field and belongs to the Uruguay orogenetic Precambrian cycle. In the north there are sedimentary rocks and granites of the Upper Precambrian period.The mining and processing of marble, granite, agate, amethyst and metallic minerals are declared of national interest.

  19. Incidence of early-onset dementia in Mar del Plata.

    Science.gov (United States)

    Sanchez Abraham, M; Scharovsky, D; Romano, L M; Ayala, M; Aleman, A; Sottano, E; Etchepareborda, I; Colla Machado, C; García, M I; Gonorazky, S E

    2015-03-01

    Early-onset dementia (EOD) is defined as dementia with onset before the age of 65 years. EOD is increasingly recognised as an important clinical and social problem with devastating consequences for patients and caregivers. Determine the annual crude incidence rate and the specific incidence rates by sex and age in patients with EOD, and the standardised rate using the last national census of the population of Argentina (NCPA), from 2010. Hospital Privado de Comunidad, Mar del Plata, Argentina, attends a closed population and is the sole healthcare provider for 17 614 people. Using the database pertaining to the Geriatric Care department, we identified all patients diagnosed with EOD between 1 January, 2005 and 31 December, 2011. EOD was defined as dementia diagnosed in patients younger than 65. The study period yielded 14 patients diagnosed with EOD out of a total of 287 patients evaluated for memory concerns. The crude annual incidence of EOD was 11 per 100 000/year (CI 95%: 6.25-19.1): 17 per 100 000 (CI 95%: 7.2-33.1) in men and 8 per 100 000 (CI 95%: 3.4-17.2) in women. We observed a statistically significant increase when comparing incidence rates between patients aged 21 to <55 years and ≥ 55 to <65 years (3 vs 22 per 100 000, P=.0014). The rate adjusted by NCPA census data was 5.8 cases of EOD habitants/year. This study, conducted in a closed population, yielded an EOD incidence rate of 11 per 100 000 inhabitants/year. To the best of our knowledge, this is the first prospective epidemiological study in Argentina and in Latin America. Copyright © 2013 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

  20. A Numerical Study of the Plata River Plume Along the Southeastern South American Continental Shelf

    Science.gov (United States)

    2005-01-01

    the effect of ambient shelf currents, level decreased by -0.20 and -0.55 in at the estuary and which would be essential in the determination of the 142...Res. SI 39, realistic wind and tidal forcing. J. Geophys. Res., 101 (submitted). (C2):3435-3455. Piola, A. R. 2002. El impacto del Plata sobre la...discharge on the continental impactos en el Plata y en la regi6n pampeana. Vol. 1. shelf. 1. Modeling the river plume and the inner shelf Assoc. Bonaerense de

  1. Rio de la Plata river: as paleoenvironmental focus using diatoms as proxies

    International Nuclear Information System (INIS)

    Perez, L; Garcia-Rodriguez, F; Hanebuth, T.

    2012-01-01

    The objective of this study is the reconstruction of the environmental history of the Rio de la Plata system in relation to the anthropogenic impact and historical changes in the flow with emphasis on salinity variations during the late Holocene. For this reason it was analyzed the composition of diatoms (grouped in freshwater (D), saline (S) and marine (M))

  2. Undergraduate education and training in optics at the Universidad Nacional de La Plata

    Science.gov (United States)

    Garavaglia, Mario

    2000-06-01

    After few historical and statistical data related to the Universidad Nacional de La Plata, follows a description of activities on undergraduate training in Optics at the Laboratorio de Optica, belonging to the Faculty of Astronomical and Geophysical Sciences, and on undergraduate education in Optics at the Departamento de Fisica, belonging to the Faculty of Exact Sciences.

  3. Occurrence of Microcystis aeruginosa and microcystins in Río de la Plata river (Argentina

    Directory of Open Access Journals (Sweden)

    Darío Andrinolo

    2007-07-01

    Full Text Available This paper is the first report on microcystins producer blooms of Microcystis aeruginosa in the Argentinean coast of the Río de la Plata river, the most important drinking water supply of Argentina. The distribution of toxic cyanobacterium Microcystis cf. aeruginosa blooms in the Argentinean coast of the Rio de la Plata river was studied from December 2003 and January 2006. Microcystis aeruginosa persisted in the river with values ranged between 0 - 7.8 10(4 cells ml-1. Samples of two Microcystis aeruginosa water blooms were collected at La Plata river and were analyzed by the mouse bioassay and by high-performance liquid chromatography with Diode-array and MS detector. The samples showed high hepatotoxicity in mouse bioassay and, in accordance, important amount of microcystins. The bloom samples contained microcystins LR and a variant of microcystin with a molecular ion [M+H]+= 1037.8 m/z as major components. The total toxin content found in these samples was 0.94μg/mg and 0.69μg/mg of lyophilised cells. We conclude that the presence of toxic clones of Microcystis aeruginosa in the Argentinean coast of the Río de la Plata is an actual sanitary and environmental problem and that further studies are necessary to make the risk assessment.

  4. Characterization of the permutations by block that have reversible one dimensional cellular automata; Caracterizacion de las permutaciones en bloque que representan automatas celulares unidimensionales reversibles

    Energy Technology Data Exchange (ETDEWEB)

    Seck Tuoh Mora, J. C. [Instituto Politecnico Nacional, Mexico, D. F. (Mexico)

    2001-06-01

    We present a review of reversible one dimensional cellular automata and their representation by block permutations. We analyze in detail the behavior of such block permutations to get their characterization. [Spanish] En el siguiente escrito se da una revision a la representacion y comportamiento de automatas celulares unidimensionales reversibles por medio de permutaciones en bloque. Hacemos un analisis detallado del comportamiento de dichas permutaciones para obtener su caracterizacion.

  5. Simulation of the transport of suspended particulate matter in the Rio de la Plata

    Energy Technology Data Exchange (ETDEWEB)

    Hausstein, H.

    2008-11-06

    Numerical simulations of the transport of Suspended Particulate Matter in the Rio de la Plata estuary were performed with a three dimensional model for coastal waters driven by wave sand currents. Aturbulence based flocculation approach is implemented to the model. The model is for the first time applied under heavy conditions, since the Rio de la Plata has discharges up to 25000 m{sup 3}/s and SPM concentrations up to 300-400 mg/l. Such concentrations are also difficult to compute from satellite measurements. SeaWiFs satellite images served for the validation of the model results. The model is able to reproduce the shape and the position of the front as well as the zone of the turbidity maximum. It also identifies the zones of erosion and deposition which is of significant importance because of the dense ship traffic along the navigational channels towards Buenos Aires and the cities upstream the rivers. (orig.)

  6. The influence of abiotic factors present in the Rio de la Plata over the chromium genotoxicity

    International Nuclear Information System (INIS)

    Lopez, L.C.; Moretton, J.

    1997-01-01

    The alterations suffered by the well-known environmental genotoxic agent, Cr(V I), were studied. Cr(V I) salts were dissolved in water effluent river receptors waters such as from the Rio de la Plata. The influence of abiotic factors present in this kind of water was evaluated using the Rec. assay in Bacillus subtilis. The results detected a soluble fraction that potentiated Cr(V I) genotoxicity. This substance (or group of substances) is sensible to sterilization by heat and UV radiation, and its activity seems to decrease with particulate matter. Its genotoxicity was not affected by high concentrations of particulate matter in the Rio de la Plata water. In samples where chromium salts were added to raw river water, abiotic interference due to sterilization process occurred. A decrease in genotoxicity was found after filtration through inorganic filters (0.22 μ m) and an increase was noticed after exposure to UV radiation. (Author)

  7. Resiliencia y engagement en el sector hotelero en la ciudad de Mar del Plata

    OpenAIRE

    Redondo, Ana Isabel; Arraigada, Mariana Cecilia

    2015-01-01

    Desde el marco de la psicología de la salud ocupacional positiva, nos proponemos realizar un estudio descriptivo sobre las variables resiliencia y engagement en el sector hotelero de la ciudad de Mar del Plata. Para tal fin, se utilizaran dos instrumentos con formato de cuestionario auto-administrado, a saber: RSA (Escala de Resiliencia en Adultos) y UWES (Utrech Work Engagement Scale) que miden dichas variables a aplicar en una muestra compuesta por 80 personas, todas ellas empleados de dos ...

  8. Una herramienta cartográfica digital basada en XML para la ciudad de La Plata

    Directory of Open Access Journals (Sweden)

    Nadia Kreimer

    2010-06-01

    Full Text Available El trabajo presenta una aplicación específica desarrollada a partir la integración de dos herramientas informáticas: Google Maps y un lenguaje de programación de alto nivel, en nuestro caso Octave. La API de Google Maps en Javascript permite la construcción de objetos espaciales. Integrando el mismo con algoritmos originales que resuelvan la geocodificación de las calles de La Plata y el manejo de una base de datos es posible brindar un servicio de localización. El ejemplo que se presenta es el de la localización de las farmacias más cercanas a un cierto domicilio. Se le pide a los usuarios que ingresen su dirección; con estos datos le son devueltas las tres farmacias de turno más cercanas. El código resulta fácilmente adaptable a otro tipo de requerimientos: estaciones de servicio, restaurantes, etcétera siendo su única limitación que la geocodificación está desarrollada para la ciudad de La Plata.This paper presents a specific application developed by the integration of two tools: Google Maps and a high level programming language: Octave. The Google Maps API in Javascript allows the construction of space objects. This language integrated with algorithms that solve the original geocoding of the streets of La Plata and management of a database can provide a service location. The example presented is the location of the nearest pharmacies to a certain address. Users are prompted to enter their address and the system returns the three closest pharmacies.The code is easily adaptable to other types of requirements: gas stations, restaurants, etc.; its only limitation is that the geocoding is developed for the city of La Plata.

  9. Cenozoic deposits exposed along Rio de la Plata coast in the Canelones Department (Uruguay)

    International Nuclear Information System (INIS)

    Goso Aguilar, C.; Spoturno, J.

    2004-01-01

    This paper allows to know some sedimentological and stratigraphical features of the Cenozoic deposits exposed along Rio de la Plata coast in the Canelones department, Uruguay. The results, mainly collected from metric thickness of local stratigraphical sections and coastal outcrops of that region are presented. Both Tertiary and Quaternary sediments are present, however transitional Pleistocenic deposits of Chuy Formation and continental sediments of Libertad Formation are more dominant [es

  10. More than two decades after the introduction of Limnoperna fortunei (Dunker 1857 in La Plata Basin

    Directory of Open Access Journals (Sweden)

    M. A. Pessotto

    2018-01-01

    Full Text Available Abstract The golden mussel, Limnoperna fortunei, is an Asian freshwater bivalve introduced in South America in the beginning of the 1990’s, probably through ballast water releases in La Plata River estuary. It dispersed north through Paraná, Uruguay and Paraguay Rivers. The study evaluated the macroscale (18° to 34° S; 45° to 60° W distribution of L. fortunei (larval stages in the main rivers and reservoirs of La Plata Basin. Samplings were performed through 68 µm vertical plankton net hauls. Limnological variables were simultaneously determined. Larvae abundance correlated significantly with oxygen (positively in summer, with temperature (positively in winter and with total phosphorus and total nitrogen (both negatively in winter. We expected densities to decrease towards north (latitudinal gradient and increase in lentic conditions (reservoirs. Despite maximum density was found near the introduction point (La Plata River similar value was also observed 2,000 km north (Paraguay River. The first hypothesis was refuted. The second hypothesis was partially accepted. Abundances were consistently higher in summer. Higher trophic conditions and fast flow seem to inhibit population growth. Food resources (chlorophyll a locally influenced temporal variation. Limnoperna fortunei is widely distributed in La Plata basin, reaching high larval densities superior to 10,000 ind. m-3, in all major sub-basins. The species exhibits a high intrinsic dispersal ability (free planktonic larvae, wide tolerance to environmental factors and dispersion is potentialized by natural dispersion processes (e.g. fauna displacement and human facilitation (e.g. commercial navigation.

  11. The International Summer School on Land Cover Change and Hydroclimate of the La Plata Basin

    Science.gov (United States)

    Berbery, Ernesto Hugo; Herdies, Dirceu L.; Alcaraz-Segura, Domingo; de Goncalves, Luis G. G.; Lettenmaier, Dennis P.; Toll, David

    2011-01-01

    The La Plata Basin (LPB) in southern South America has been subject to land cover and land use changes (LCLUCs) since colonial times and with an accelerated rate in the last decades and over extensive areas. The work of Ameghino even suggested that there were relations between those land use changes and the frequency of droughts and floods in the region. Despite this early knowledge, not much is known of the potential impacts of LCLUC on the hydroclimate of the La Plata basin. Besides, over the last century much of the La Plata Basin has had a reported increase in precipitation and heavy rains, and these changes along with an increase in population growth - have resulted in more adverse effects from flooding. To draw attention to these issues, during two weeks in November 2009 the International Summer School on Land Cover Change and Hydroclimate of the La Plata Basin was organized at the grounds of the Itaip Hydropower Plant in Brazil. The school was the result of the combination of interests between the La Plata Basin Regional Hydroclimate Project, the Inter-American Institute for Global Change Research (IAI), and the International Hydroinformatics Center (IHC) in Itaip . LPB is an umbrella project endorsed by the Global Energy and Water Cycle Experiment (GEWEX) and the Climate Prediction and Variability (CLIVAR), both of the World Climate Research Programme (WCRP). LPB has made a priority to train young scientists and promote interdisciplinary collaborations in areas related to Climate, Hydrology, Ecology and Agriculture. The IAI, with a similar agenda, was a natural partner to develop this Summer School, which in turn benefited from Itaipu s interest in relating with the scientific community of neighboring countries. The choice of location (Itaip Technological Park) was made so that participants could relate research usually done at academic institutions to applications and operations at one of the largest hydropower plants in the world. The school was attended

  12. Characterization of n-TiO{sub 2} thin films modified with silver nanoparticles; Caracterizacion de peliculas delgadas de n-TiO{sub 2} modificadas con nanoparticulas de plata

    Energy Technology Data Exchange (ETDEWEB)

    Cueto, L.F. [Universidad Autonoma de Nuevo Leon, Monterrey, N.L. (Mexico). Dept. de Biotecnologia e Ingenieria de Alimentos; Sanchez-Cervantes, E.M. [Universidad Autonoma de Nuevo Leon, San Nicolas de los Garza, N.L. (Mexico). Facultad de Ciencias Quimicas. Lab. de Vidrio

    2010-07-01

    Carbon dioxide accumulation in the atmosphere has gained much attention and has reopened many research lines that initiated two or three decades ago. Electrochemical reduction represents one of the most discussed methods, especially where semiconductor and metal-semiconductor cathodes are used to achieve CO{sub 2} transformation into higher-energy products. In the present work, the influence of silver nanoparticles upon CO{sub 2} reduction on n-TiO{sub 2} cathodes in aqueous media is presented. Silver nanoparticles with an average diameter of 250nm were deposited on n-TiO{sub 2} surfaces by the electrochemical Double-Pulse Potential method. A Grazing-Incidence X-Ray Diffraction structural analysis is presented showing the presence of metallic silver, while Atomic Force Microscopy shows surface roughness and particle size before and after surface modification. These measurements were confirmed by Scanning-Electron Microscopy acquainting for the formation of metal particles on the n-TiO{sub 2} surface. Enhancement of CO{sub 2} reduction by the presence of silver on cathodes is shown by cyclic voltammetry. (author)

  13. The Hydrologic Regime of the La Plata Basin in South America

    Science.gov (United States)

    Berbery, E. H.; Barros, V. R.

    2002-12-01

    The main components of the hydrologic cycle of the La Plata basin in southeastern South America are investigated using a combination of observations, satellite products and National Centers for Environmental Prediction-National Center for Atmospheric Research (NCEP-NCAR) global reanalyses. La Plata basin is second only to the Amazon basin in South America, and plays a critical role in the economies of the region. It is a primary factor in energy production, water resources, transportation, agriculture and livestock. Of particular interest was to evaluate the annual cycle of the hydrologic cycle components. The La Plata annual-mean river discharge is about 21,000 m3 s-1, and the amplitude of the mean annual cycle of La Plata River discharge is small: it is slightly larger during late summer, but continues with large volumes even during winter. The reason is that different precipitation regimes over different locations contribute to the total river discharge. One regime is found toward the northern boundary, where precipitation peaks during summer in association with the southernmost extension of the monsoon system. A second one is found over the central part of the basin, where precipitation peaks at different times in the seasonal cycle. Further analysis of the main tributaries of La Plata (Paran , Uruguay and Paraguay) reveals that each has a well defined annual cycle, but with different phases that can be traced primarily to each basin's physiography and precipitation regime. The upper and middle portions of the Paran River are most influenced by the summer monsoon regime, thus the river has a maximum discharge in late summer. The annual cycle of precipitation over the Uruguay River basin has two maxima, one in late autumn and the second one in spring and, consistently, the river discharge is largest in winter and spring. The smooth annual cycle of the Paraguay River discharge, with a maximum in winter, is the result of the Pantanal, a large wetland that

  14. Vertisoles hidromórficos de la planicie costera del Río de La Plata, Argentina Hydromorphic vertisols of the Rio de La Plata coastal plain, Argentina

    Directory of Open Access Journals (Sweden)

    Perla Imbellone

    2011-12-01

    Full Text Available Los suelos predominantes en la Planicie costera del río de La Plata, provincia de Buenos Aires, son Vertisoles hidromórficos. Se estudian cuatro suelos representativos en los partidos de La Plata, Ensenada y Berazategui. Se describen y analizan detalladamente las propiedades pedológicas y sedimentológicas. El objeto de esta contribución es analizar: a- la granulometría y mineralogía de los Vertisoles hidro-mórficos de la Llanura de fango del río de la Plata; b- su influencia en la generación de los rasgos morfológicos y c- los procesos de pedogénesis asociados. La morfología de los suelos muestra rasgos de vertisolización e hidromorfismo principalmente en los horizontes superiores y medios de los suelos. Son abundantes los agregados cuneiformes y angulares moderados y fuertes en el solum, con super­ficies de deslizamiento interpedales, a veces estriadas, visibles en distintos niveles de observación. La matriz puede ser moderadamente o marcadamente anisotrópica y muestra zonas de anisotropismo óptico que atraviesan el material fino con patrones variados o aureolas anisotrópicas alrededor de los poros y granos. La hidromorfia es marcada, con anegamientos frecuentes de origen pluvial; la capa freática está a profundidad general entre 0,80 y 1,20 m, por lo que estarían en condiciones de episaturación y endosaturación en distintos mo­mentos del año. Poseen variedad de rasgos redoximórficos, principalmente matrices reducidas (matices de 2,5Y y 5Y e intensidades de 2 o menores, concentraciones redox de hierro y manganeso y pátinas oscuras. La clase textural es arcillosa, con amplio predominio de la arcilla fina sobre la gruesa. Son Vertisoles illíticos, con muy elevado contenido de arcilla total que genera rasgos vérticos. La influencia hidromórfica se manifiesta por la abundancia y color de las pátinas que están relacionadas con el grado de hidromorfía dentro de cada perfil y las propiedades asociadas al proceso

  15. Generación controlada de nanocoloides de plata en materiales silíceos amorfos

    Directory of Open Access Journals (Sweden)

    Gil, C.

    2004-04-01

    Full Text Available Amorphous silica-based materials bulk and superficially doped with silver nanocolloids were prepared. Bulk doped glasses were obtained by conventional melting and doped monolithic slabs by sol-gel. Superficially doped glasses were obtained by ion-exchange and doped coatings by sol-gel. The samples were characterised by TEM and UV-VIS spectrophotometry. Depending on the composition, the silver incorporation process, and the thermal treatments, several colourings were obtained. By controlling these parameters, metallic silver nanocolloids can be generated in the matrices studied. Colloids aggregation and growing up depends on the matrix nature and on the experimental process carried out.

    Se prepararon materiales silíceos amorfos dopados con nanocoloides de plata en masa y en superficie. Se obtuvieron vidrios dopados en masa por fusión convencional y láminas monolíticas dopadas por sol-gel. Asimismo se prepararon vidrios dopados superficialmente por cambio iónico y recubrimientos dopados por sol-gel. Los materiales se caracterizaron por MET y espectrofotometría UV-VIS. Dependiendo de la composición del material, del proceso de incorporación de la plata y de los tratamientos térmicos, se obtuvieron diferentes coloraciones. El control de estas variables permitió generar nanocoloides metálicos de plata en las matrices estudiadas. La agregación y crecimiento de los coloides depende de la naturaleza de la matriz y del proceso experimental utilizado.

  16. Preferencias de los huéspedes de hostels de la ciudad de La Plata

    OpenAIRE

    De la Cruz, Gastón Miguel

    2013-01-01

    La presente tesis tiene como objeto estudiar las preferencias de huéspedes de un grupo de hostels de la ciudad de La Plata, con el fin de determinar la existencia de una demanda que tenga como principal preferencia a un atributo de índole social. Para cumplir con este objetivo se utilizó la técnica estadística análisis conjunto (conjoint analysis en inglés) la cual obligó a descomponer el concepto hostel en seis (6) atributos, de los cuales tres (3) atributos entran en la definición de índole...

  17. Conflicto de identidad : indefinición sexual en tres poetas de la Edad de Plata

    OpenAIRE

    Gómez Garrido, Marta

    2013-01-01

    Artículo sobre la presencia de un conflicto identitario relacionado con el género en la obra de tres poetas de la llamada Edad de Plata Española: Lucía Sánchez Saornil, Ana María Martínez Sagi y Carmen Conde. Article about the existence of a gender-related identity conflict in three female poets of the Silver Age of Spanish Literature: Lucía Sánchez Saornil, Ana María Martínez Sagi and Carmen Conde.

  18. Satisfacción del cliente de obras particulares de la Municipalidad de La Plata

    OpenAIRE

    Pizzorno, Mariano

    2013-01-01

    Evaluación del nivel de satisfacción de los clientes del servicio de Obras Particulares de la Municipalidad de La Plata en relación a: - El grado de conocimiento de los servicios que brinda el municipio. - La imagen que tiene el ciudadano del municipio. - La importancia de cada atributo del servicio: en relación a la atención al público, a la infraestructura y equipamiento y a los procesos para la realización de trámites. - El grado de satisfacción del ...

  19. Tostación de un concentrado refractario de oro y plata

    Directory of Open Access Journals (Sweden)

    Coronado, J. H.

    2012-06-01

    Full Text Available In processing of precious metal ores with high pyrite content, refractory concentrates are obtained, which are difficult to process. A refractory gold and silver concentrate was leached with sodium cyanide. Results show low extraction percentages, being 34 % of gold and 40 % of silver. A roasting method to oxidize the concentrate was used, making it more susceptible to cyanidation, hence a more efficient way to extract precious metals. The variables include roasting temperature and roasting and cyanidation time. In addition, the hot calcine was added to the leaching solution at room temperature to analyze the effect on particle size and recovery. The best results, although not entirely satisfactory (50 % of gold and 61 % of silver were obtained by roasting the concentrate for 4 h at 600 °C, followed by cyanidation for 20 h. The lime consumption to raise the pH to about 11.3 was increased markedly to 25 kg/m3.

    En el procesamiento de minerales de metales preciosos con altos contenidos de pirita, se obtienen concentrados refractarios difíciles de procesar. En este estudio se lixivió un concentrado refractario de oro y plata con cianuro de sodio, obteniéndose extracciones de 34 % para oro y 40 % para plata. Se utilizó el método de tostación para oxidar el concentrado, haciéndolo más susceptible a la cianuración, y extraer más eficientemente el oro y la plata. Las variables analizadas fueron: temperatura de tostación y tiempos de tostación y cianuración. Además, la calcina caliente se agregó a la solución lixiviante a temperatura ambiente para analizar el efecto en el tamaño de partícula y recuperación. Los mejores resultados, aunque no del todo satisfactorios (50 % oro y 61 % plata, se obtuvieron mediante tostación del concentrado durante 4 h a temperaturas de 600 °C, seguido de una cianuración de 20 h. El consumo de cal para elevar el pH a 11,3, se incrementó notablemente hasta 25 kg/m3.

  20. Archivo de placas astrométricas del Observatorio de La Plata

    Science.gov (United States)

    di Sisto, R.; Orellana, R. B.

    Se ha realizado una base de datos con las placas fotográficas obtenidas con el Astrográfico del Observatorio de La Plata. Se han clasificado un total de 3000 placas obtenidas para asteroides y cometas. El acceso a la base de datos se hará por FTP y la misma contendrá la siguiente información: fecha y tiempo de exposición, coordenadas del centro de placa, tipo de emulsión fotográfica, estado de la placa, objeto fotografiado.

  1. DISPERSIÓN DE LUZ POR UNA NANOPARTÍCULA DE PLATA CON FORMA ESFEROIDAL PROLATA

    OpenAIRE

    Alejandro Castellanos Jaramillo; Arnulfo Castellanos Moreno

    2016-01-01

    Usando el método de diferencias finitas en el dominio del tiempo se estudia la incidencia y dispersión de radiación electromagnética de una nanopartícula de plata con forma esferoidal prolata. Se obtiene la distribución de frecuencias del vector de Poynting dispersado en el régimen casi estacionario y se estudia el estado de radiación de la nanopartícula cuando el pulso de luz ha dejado de perturbarla. Los resultados son de interés didáctico

  2. Gravimetric study on the western edge of the Rio de La Plata craton

    International Nuclear Information System (INIS)

    Rame, G; Miro, R

    2010-01-01

    This work is about the gravimetric study on the western edge of the Rio de la Plata craton which belongs to the Gondwana fragment in the south of Brazil, Uruguay and central eastern of Argentina. The work consisted of a survey of 332 gravimetric and topographic stations extended from the western edge of the Sierra Chica de Cordoba up to 200 km east on the pampas. The gravity values observed (gobs) were obtained using a LaCoste §Rom berg gravimeter G-961 and 200T Sodin both with 0.01 mGal, referred to IGSN71 (International Gravity Standardization Net 1971) network

  3. DISPERSIÓN DE LUZ POR UNA NANOPARTÍCULA DE PLATA CON FORMA ESFEROIDAL PROLATA

    Directory of Open Access Journals (Sweden)

    Alejandro Castellanos Jaramillo

    2016-06-01

    Full Text Available Usando el método de diferencias finitas en el dominio del tiempo se estudia la incidencia y dispersión de radiación electromagnética de una nanopartícula de plata con forma esferoidal prolata. Se obtiene la distribución de frecuencias del vector de Poynting dispersado en el régimen casi estacionario y se estudia el estado de radiación de la nanopartícula cuando el pulso de luz ha dejado de perturbarla. Los resultados son de interés didáctico

  4. Programas de salud sexual y reproductiva y maternidad adolescente en La Plata (Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Susana Ortale

    2009-12-01

    Full Text Available La mirada estigmatizante de la maternidad en la adolescencia y el interés por controlar la sexualidad por parte del sector sanitario, es reciente y diferente para hombres y mujeres. Sabemos que las categorías género y edad, en tanto construcciones culturales que aluden a relaciones básicas de desigualdad -atravesadas por estructuras económico-políticas particulares-, están cargadas de significados que se dirimen en un campo social predispuesto a reforzar estereotipos naturalizantes y relaciones de dominación. El estudio se ubica en la problemática general del reconocimiento de derechos presente en los programas de salud sexual y reproductiva que tienen como destinatarias a mujeres adolescentes pobres. El recorte pone en foco el contraste entre el marco normativo y el significado que asume la maternidad para las adolescentes. Para ello, se analizan programas de salud nacionales, de la Pcia. de Buenos Aires y de la municipalidad de La Plata y discursos obtenidos en entrevistas realizadas a veinte adolescentes residentes en barrios pobres de la ciudad de La Plata. El análisis de los programas explora la incorporación del enfoque de género y la interpretación de los problemas de sexualidad/reproducción de l@s adolescentes en el marco de los derechos humanos y el de los discursos de las entrevistadas indaga su interpelación.Stigmatizing gaze of teenage motherhood and the aim to control the sexuality from the health sector, is recent and different for men and women. We know that gender and age categories, as cultural constructions that refer to basic relations of inequality-crossed by particular political-economic structures, are loaded with meanings that are settled in a social and naturalizing field predisposed to reinforce stereotypes and relations of domination. The study is placed in the general problem of aknowledgement of rights in the programs of sexual and reproductive health in adolescent girls from low environment. This frame

  5. Characterization of the billow applied to Tuxpan, Veracruz; Caracterizacion del oleaje aplicada a Tuxpan, Veracruz

    Energy Technology Data Exchange (ETDEWEB)

    Rosales Sierra, Victor

    1999-07-01

    In this work, the criteria for the wave temporal and spectral statistical analysis were reviewed. These analysis are applied to the site Tuxpan, Veracruz, in the Mexican Gulf coast. In the temporal statistic analysis, the high (Rayleigh, Tayfun and Carter) and period (Bretchneider, Cavanie and Longuet-Higgins) theoretic probability distributions are compared with field data from Tuxpan. In the other hand, in the frequency domain analysis, the theoretic spectrums (Bretchneider-Mitsuyasu, Jonswap-Hasselmann, Pierson-Moscowitz, Neumann, ITTC, ISSC, TMA and Ochi-Hubble) are compared with the one obtained from Tuxpan measurements, then changes are made to some spectrums in order to better couple to field data. Finally, some recommendations are made to improve the wave data acquisition and analysis methods. From the study results, it's important to mention that the Tayfun high probability distribution and the Cavanie period probability distribution better fit Tuxpan field data. In the spectral analysis, the Bretchneider spectrum, modified by Mitsuyasu, better coupled to the spectrum obtained from Tuxpan field data. In the temporal statistical analysis, correct the mean level using the parabolic approximation, in order to eliminate the tidal and long period wave effects, it is recommended. For the registered individual wave calculus the zero up cross method was used. [Spanish] En este trabajo se revisan los criterios para el analisis estadisticos temporal y espectral del oleaje, mismos que son aplicados para la caracterizacion del oleaje en Tuxpan, Veracruz. En cuanto al analisis estadistico temporal, se comparan las distribuciones teoricas de probabilidad de altura de Rayleigh, Tayfun y Carter; y las de periodo de Bretchneider, Cavanie y Longuet-Higgins contra las resultantes de las mediciones en campo. Por otro lado y concerniente al analisis en el dominio de la frecuencia, se comparan los espectros teoricos de Bretchneider- Mitsuyasu, Jonswap-Hasselmann, Pierson

  6. A Darwinian mystery: fluctuations in runoff from the la Plata basin (Alexander von Humboldt Medal Lecture)

    Science.gov (United States)

    Clarke, R. T.

    2012-04-01

    During the voyage of HMS Beagle, Charles Darwin sailed in a small boat along the River Paraná, a major tributary of the la Plata drainage system. He wrote about the occurrence of severe droughts (the latest of which had been termed the "gran seco") alternating with periods of severe flooding. From reports received, he concluded that these events appeared to be cyclic with a period "of about fifteen years". Because extended periods of low flow in Brazilian rivers are of immense economic importance, the presentation describes a search for the material which led Darwin to this conclusion. A prolonged period of low flow in another la Plata tributary - the River Paraguay - not unlike the "gran seco" reported by Darwin, has occurred more recently; if such low flows were to recur in the future, the consequences would be severe for a region where more than 70% of energy is supplied by hydropower. A priori considerations suggest the use of statistical long-memory models for predicting River Paraguay water-levels, and some preliminary results from their use are presented.

  7. Assessing residual hydropower potential of the La Plata Basin accounting for future user demands

    Directory of Open Access Journals (Sweden)

    I. Popescu

    2012-08-01

    Full Text Available La Plata Basin is shared by five countries (Argentina, Bolivia, Brazil, Paraguay and Uruguay, which have fast growing economies in South America. These countries need energy for their sustainable development; hence, hydropower can play a very important role as a renewable clean source of energy. This paper presents an analysis of the current hydropower production and electricity demand in La Plata Basin (LPB, and it analyses the maximum and residual hydropower potential of the basin for a horizon of 30 yr (i.e. year 2040. Current hydropower production is estimated based on historical available data, while future energy production is deduced from the available water in the catchment (estimated based on measured hydrographs of the past years, whereas electricity demand is assessed by correlating existing electricity demand with the estimated population growth and economic development. The maximum and residual hydropower potential of the basin were assessed for the mean annual flows of the present hydrological regime (1970–2000 and topographical characteristics of the area.

    Computations were performed using an integrated GIS environment called VAPIDRO-ASTE released by the Research on Energy System (Italy. The residual hydropower potential of the basin is computed considering first that the water supply needs for population, industry and agriculture are served, and then hydropower energy is produced. The calculated hydropower production is found to be approximately half of the estimated electricity demand, which shows that there is a need to look for other sources of energy in the future.

  8. Contribution of Isotopic Tools to the Numerical Simulation of the Mar del Plata Coastal Aquifer, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Bocanegra, E.; Martinez, D. E. [Instituto de Geologia de Costas y del Cuaternario, UNMDP (Argentina); Pool, M.; Carrera, J. [Instituto de Diagnostico Ambiental y Estudios del Agua, CSIC (Spain)

    2013-07-15

    Over-exploitation in the coastal aquifer in Mar del Plata, Argentina, led to a seawater intrusion process affecting groundwater by salinization. The aim of this paper is to show the contribution of isotopic techniques to generate the numerical flow and transport model of the Mar del Plata aquifer. On the basis of the hydrogeological conceptual model, a numerical model was constructed. It consists of a multilayer aquifer in the urban area with 2 layers separated by an aquitard and a monolayer aquifer in the rest of the basin. The isotopic difference recorded in groundwaters allow the identification of the origin of the recharge and the confirmation of the presence of the hydrogeological environments incorporated in the numerical model. Flow simulation reflects the evolution of piezometric heads. Chloride transport simulation represents the salinization process due to seawater intrusion and the subsequent backward movement of the interface due to the abandonment of salinized wells. The results of numerical simulation confirm the conceptual model and reproduce the impact of the adopted management strategies. (author)

  9. Assessing residual hydropower potential of the La Plata Basin accounting for future user demands

    Science.gov (United States)

    Popescu, I.; Brandimarte, L.; Perera, M. S. U.; Peviani, M.

    2012-08-01

    La Plata Basin is shared by five countries (Argentina, Bolivia, Brazil, Paraguay and Uruguay), which have fast growing economies in South America. These countries need energy for their sustainable development; hence, hydropower can play a very important role as a renewable clean source of energy. This paper presents an analysis of the current hydropower production and electricity demand in La Plata Basin (LPB), and it analyses the maximum and residual hydropower potential of the basin for a horizon of 30 yr (i.e. year 2040). Current hydropower production is estimated based on historical available data, while future energy production is deduced from the available water in the catchment (estimated based on measured hydrographs of the past years), whereas electricity demand is assessed by correlating existing electricity demand with the estimated population growth and economic development. The maximum and residual hydropower potential of the basin were assessed for the mean annual flows of the present hydrological regime (1970-2000) and topographical characteristics of the area. Computations were performed using an integrated GIS environment called VAPIDRO-ASTE released by the Research on Energy System (Italy). The residual hydropower potential of the basin is computed considering first that the water supply needs for population, industry and agriculture are served, and then hydropower energy is produced. The calculated hydropower production is found to be approximately half of the estimated electricity demand, which shows that there is a need to look for other sources of energy in the future.

  10. Geotechnical characterization through in situ and laboratory tests of several geological formations present in the route of the Future Fix Connection between Spain and Morocco through Gibraltar Strait; Caracterizacion geotecnica mediante ensayos in situ y de laboratorio de algunas formaciones geologicas presentes en la traza de la Futura Conexion Fija entre Espana y Marruecos a traves del estrecho de Gibraltar

    Energy Technology Data Exchange (ETDEWEB)

    Perucho Martinez, A.; Diez Torres, J. A.; Muniz Menendez, M.; Cano Linares, H.; Ruiz Fonticiella, J. M.

    2015-07-01

    CEDEX and SECEGSA (Sociedad Española para la Comunicación Fija a través del Estrecho de Gibraltar), Have been collaborating since a few decades ago to study different technical aspects related to the Fix Connection through the Gibraltar Strait, mainly in relation to the geological and geotechnical properties of the different formations present in the route. In order to do so, many studies of geotechnical characterization of materials, in situ and laboratory testing campaigns have been carried out. Furthermore, they have participated in some Expertise Committees carrying out some advice work related to studies performed by other organizations. This paper presents a brief description of the most relevant aspects of the main geological and geotechnical studies performed related to this Project of the Future Fix Connection and obtained through the study of SECEGSAs extensive data base. Moreover, it includes a synopsis of the geotechnical characterization carried out through in situ and laboratory tests on different Miocene and Eocene formations from the Algeciras Unit, present in the route of the future Fix Connection between Spain and gibraltar through the Gibraltar Strait. (Author)

  11. Characterization by means of geological and geophysical techniques of the hydrogeologic limit between the Guadiana and Jucar watersheds in the Plain of La Mancha, Spain; Caracterizacion de la divisoria hidrogeologica Guadiana-Jucar en la Llanura Manchega mediante tecnicas geologicas y geofisicas

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Gutierrez, J.; Plata Torres, J. L.; Mejias Moreno, M.

    2013-09-01

    The characterization of the dividing hydrogeological Guadiana-Jucar (DHGJ) in the Plain of La Mancha, (groundwater dividing line), involves great difficulties, mainly due to the poor outcrop of the Mesozoic and Tertiary formations which constitute major aquifers and the fact of the existence of a broad detrital coating, Plio-Quaternary in age, which prevents the observation of the geological structure. Although the DHGJ in the La Mancha plain has been normally interpreted through piezometric data, this method cannot by itself explain the origin, since the geological structure of the basement is unknown. This work shows the results of the research carried out in this area through gravity and electrical geophysical techniques, and the interpretation of three boreholes drilled in 2010 by the Guadiana River Basin Authority (CHG). The most remarkable result is the absence of any geological threshold in the subsoil, meaning that the hydro-geological divide can only respond to differences in the hydraulic potential within the aquifer. Consequently, the groundwater divide line is subject to spatial variations since the hydraulic head depends on natural and anthropic factors. (Author)

  12. Evaluación de la vulnerabilidad socio-ambiental del periurbano de Mar del Plata

    Directory of Open Access Journals (Sweden)

    Daiana Daga

    2015-12-01

    Full Text Available RESUMEN El periurbano de Mar del Plata conforma un espacio dinámico y heterogéneo, susceptible a distintas intervenciones que pueden generar impactos ambientales con consecuencias negativas sobre la población expuesta. El presente trabajo evalúa la vulnerabilidad socio-ambiental del periurbano marplatense en 2010, distinguiendo sectores críticos y principales aspectos que determinan las condiciones extremas. Para ello se construyó un Índice de Vulnerabilidad Socio-Ambiental (IVSA y se examinó su distribución espacial.La vulnerabilidad socio-ambiental hace referencia a las condiciones de la población y su entorno inmediato para enfrentar efectos adversos. Las situaciones más críticas (IVSA= 0,46–0,58 pertenecen a los sectores del periurbano definidos por los ejes que conforman las Rutas Nº 226 y Nº 88. Las dimensiones sanitaria, educativa y ambiental determinan en mayor medida la distribución del IVSA. El procedimiento metodológico empleado permitió identificar áreas críticas, siendo transferible a otras situaciones con problemáticas semejantes. ABSTRACT Mar del Plata peri-urban conforms a heterogeneous and dynamic space, susceptible to many interventions that generate significant impacts with negative consequences on the exposed population. This paper evaluates the socio-environmental vulnerability of the Mar del Plata peri-urban in 2010, distinguishing critical sectors and principle aspects that determine the extreme conditions. To this end, it was built a Socio-Environmental Vulnerability Index (SEVI and its spatial distribution was examined. The socio-environmental vulnerability refers to the conditions of the population and their environment to deal with adverse effects. The most critical situations (SEVI= 0.46-0.58 belongs to the peri-urban sectors that were defined by the 226 and 88 roads. The health, education and environmental dimensions determine the SEVI distribution. The methodological procedure employed allowed

  13. Updates since Brown v. Plata: alternative solutions for prison overcrowding in California.

    Science.gov (United States)

    Horne, Christopher; Newman, William J

    2015-03-01

    With the number of inmates under the care of the California Department of Corrections and Rehabilitation (CDCR) swelling over the past few decades, California faces a challenge. The U.S. Supreme Court ruled in their 2011 decision in Brown v. Plata that overcrowding violates inmates' Eighth Amendment rights, specifically that they are denied adequate medical and mental health care. Federally mandated release programs have historically raised some concerns regarding public safety and fiscal efficiency. Given the large number of mentally ill inmates in the United States, alternatives such as assisted outpatient treatment, mental health courts, and increased funding for substance use treatment can be used proactively to reduce the CDCR population and provide long-term solutions to the overcrowding problem. These alternatives have already shown long-term cost savings in addition to reducing the recidivism of individuals involved and would help provide appropriate diversion for mentally ill individuals. © 2015 American Academy of Psychiatry and the Law.

  14. Microplastics in gut contents of coastal freshwater fish from Río de la Plata estuary.

    Science.gov (United States)

    Pazos, Rocío S; Maiztegui, Tomás; Colautti, Darío C; Paracampo, Ariel H; Gómez, Nora

    2017-09-15

    The presence of microplastics (MPs) in gut contents of coastal freshwater fish of the Rio de la Plata estuary was studied. Samples were taken in six sites where 87 fish belonging to 11 species and four feeding habits were captured. Presence of MPs was verified in the 100% of fish. The fibres represented the 96% of MPs found. The number of MPs in gut contents was significantly higher close to sewage discharge. There was not found relationship between number of MPs and fish length, weight or feeding habit. The spatial differences in mean number of MPs in fish observed in this study, suggest that environmental availability of MPs could be of great importance to explain the differences found among sampling sites analysed. This work represents the first study about the interaction between MPs and aquatic organisms in this important estuarine ecosystem of South America. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Educación literaria en las novelas de colegios de la "Edad De Plata"

    Directory of Open Access Journals (Sweden)

    Fermín Ezpeleta Aguilar

    2013-12-01

    Full Text Available En un periodo histórico de proliferación de colegios religiosos como es la "Edad de Plata" se consolida en la literatura española el subgénero narrativo de novelas de internado docente. El cotejo de este corpus novelístico aporta claves de investigación acerca de la educación literaria de los escritores y de las generaciones de estudiantes bachilleres de la Restauración, puesto que refleja prácticas de lectura y de escritura, actividades teatrales y canon de lecturas, en un contexto en el que la didáctica de la literatura observa una progresiva sustitución del método retórico por el historicista.

  16. DNA barcoding of odonates from the Upper Plata basin: Database creation and genetic diversity estimation.

    Directory of Open Access Journals (Sweden)

    Ricardo Koroiva

    Full Text Available We present a DNA barcoding study of Neotropical odonates from the Upper Plata basin, Brazil. A total of 38 species were collected in a transition region of "Cerrado" and Atlantic Forest, both regarded as biological hotspots, and 130 cytochrome c oxidase subunit I (COI barcodes were generated for the collected specimens. The distinct gap between intraspecific (0-2% and interspecific variation (15% and above in COI, and resulting separation of Barcode Index Numbers (BIN, allowed for successful identification of specimens in 94% of cases. The 6% fail rate was due to a shared BIN between two separate nominal species. DNA barcoding, based on COI, thus seems to be a reliable and efficient tool for identifying Neotropical odonate specimens down to the species level. These results underscore the utility of DNA barcoding to aid specimen identification in diverse biological hotspots, areas that require urgent action regarding taxonomic surveys and biodiversity conservation.

  17. Continental Influence versus marine transition in Rio de la Plata zone - internal continental shelf of the South Atlantic - a multi proxy study

    International Nuclear Information System (INIS)

    Burone, L.; Franco-Fraguas, P.; Garcia-Rodriguez, F.; Venturini, N.; Brugnoli, E.; Muniz, P.; Ortega, L.; Marin, Y.; Mahiques, M.; Nagaic, R.; Bicegoc, M.; Figueiras, R.; Salaroli, A.

    2012-01-01

    The terrigenous proxies contribution, the organic matter origin, the productivity, the hydrodynamic and the biological records were used to determine the imrprint of the continental influence along the Rio de la Plata and the Continental Atlantic

  18. [Nutritional status and body composition of poor children in the outlying neighborhoods of La Plata, Argentina].

    Science.gov (United States)

    Oyhenart, Evelia E; Torres, María F; Quintero, Fabián A; Luis, María A; Cesani, María F; Zucchi, Mariel; Orden, Alicia B

    2007-09-01

    To evaluate nutritional status and body composition as indicators of quality of life among poor children served by neighborhood soup kitchens in La Plata, Argentina. From April to November 2004, we conducted a cross-sectional study of 608 healthy children from 1-11 years of age who were being served by two neighborhood soup kitchens in the outlying areas of the city of La Plata. The sample was stratified by age and sex. Height-for-age, weight-for age, and weight-for-height, were measured, as well as BMI, muscle mass and adipose tissue. Z-scores were computed for the data. Odds ratios and the respective 95% confidence intervals were calculated. Prevalence of low weight-for-age was 9%; low weight-for-height, 3%; and low height-for-age, 15%. The prevalence of overweight and obesity were 12.5% and 7.1%, respectively. Among the study sample, 47.2% had low muscle mass and 20.4% had low adipose tissue. Among overweight and obese children, adipose tissue was 34.3% higher than that of the reference population, while muscle mass was 12.5% lower. Undernutrition and obesity are both found among the community of children studied. The high prevalence of delayed growth (i.e., low height-for-age), undernutrition (i.e., low weight-for-age), and the acute lack of muscle mass even among overweight and obese children, seem to be part of the consequences of an inevitable process that unfolds in the face of adverse living conditions.

  19. Nitrogen cycle and ecosystem services in the Brazilian La Plata Basin: anthropogenic influence and climate change

    Directory of Open Access Journals (Sweden)

    M Watanabe

    Full Text Available The increasing human demand for food, raw material and energy has radically modified both the landscape and biogeochemical cycles in many river basins in the world. The interference of human activities on the Biosphere is so significant that it has doubled the amount of reactive nitrogen due to industrial fertiliser production (Haber-Bosch, fossil fuel burning and land-use change over the last century. In this context, the Brazilian La Plata Basin contributes to the alteration of the nitrogen cycle in South America because of its huge agricultural and grazing area that meets the demands of its large urban centres - Sao Paulo, for instance - and also external markets abroad. In this paper, we estimate the current inputs and outputs of anthropogenic nitrogen (in kg N.km-2.yr-1 in the basin. In the results, we observe that soybean plays a very important role in the Brazilian La Plata, since it contributes with an annual entrance of about 1.8 TgN due to biological nitrogen fixation. Moreover, our estimate indicates that the export of soybean products accounts for roughly 1.0 TgN which is greater than the annual nitrogen riverine exports from Brazilian Parana, Paraguay and Uruguay rivers together. Complimentarily, we built future scenarios representing changes in the nitrogen cycle profile considering two scenarios of climate change for 2070-2100 (based on IPCC's A2 and B2 that will affect land-use, nitrogen inputs, and loss of such nutrients in the basin. Finally, we discuss how both scenarios will affect human well-being since there is a connection between nitrogen cycle and ecosystem services that affect local and global populations, such as food and fibre production and climate regulation.

  20. Nitrogen cycle and ecosystem services in the Brazilian La Plata Basin: anthropogenic influence and climate change.

    Science.gov (United States)

    Watanabe, M; Ortega, E; Bergier, I; Silva, J S V

    2012-08-01

    The increasing human demand for food, raw material and energy has radically modified both the landscape and biogeochemical cycles in many river basins in the world. The interference of human activities on the Biosphere is so significant that it has doubled the amount of reactive nitrogen due to industrial fertiliser production (Haber-Bosch), fossil fuel burning and land-use change over the last century. In this context, the Brazilian La Plata Basin contributes to the alteration of the nitrogen cycle in South America because of its huge agricultural and grazing area that meets the demands of its large urban centres - Sao Paulo, for instance - and also external markets abroad. In this paper, we estimate the current inputs and outputs of anthropogenic nitrogen (in kg N.km(-2).yr(-1)) in the basin. In the results, we observe that soybean plays a very important role in the Brazilian La Plata, since it contributes with an annual entrance of about 1.8 TgN due to biological nitrogen fixation. Moreover, our estimate indicates that the export of soybean products accounts for roughly 1.0 TgN which is greater than the annual nitrogen riverine exports from Brazilian Parana, Paraguay and Uruguay rivers together. Complimentarily, we built future scenarios representing changes in the nitrogen cycle profile considering two scenarios of climate change for 2070-2100 (based on IPCC's A2 and B2) that will affect land-use, nitrogen inputs, and loss of such nutrients in the basin. Finally, we discuss how both scenarios will affect human well-being since there is a connection between nitrogen cycle and ecosystem services that affect local and global populations, such as food and fibre production and climate regulation.

  1. Fungal monitoring of the indoor air of the Museo de La Plata Herbarium, Argentina.

    Science.gov (United States)

    Mallo, Andrea C; Elíades, Lorena A; Nitiu, Daniela S; Saparrat, Mario C N

    Biological agents, such as fungal spores in the air in places where scientific collections are stored, can attack and deteriorate them. The aim of this study was to gather information on the indoor air quality of the Herbarium of Vascular Plants of the Museo de Ciencias Naturales de La Plata, Argentina, in relation to fungal propagules and inert particles. This study was made using a volumetric system and two complementary sampling methods: (1) a non-viable method for direct evaluation, and (2) a viable method by culture for viable fungal propagules. The non-viable method led to ten spore morphotypes being found from related fungal sources. A total of 4401.88spores/m 3 and 32135.18 inert suspended particles/m 3 were recorded. The viable method led to the finding of nine fungal taxa as viable spores that mostly belonged to anamorphic forms of Ascomycota, although the pigmented yeast Rhodotorula F.C. Harrison (Basidiomycota) was also found. A total count of 40,500fungal CFU/m 3 air was estimated for all the sites sampled. Both the non-viable and viable sampling methods were necessary to monitor the bio-aerosol load in the La Plata Herbarium. The indoor air of this institution seems to be reasonably adequate for the conservation of vascular plants due to the low indoor/outdoor index, low concentrations of air spores, and/or lack of indicators of moisture problems. Copyright © 2016 Asociación Española de Micología. Publicado por Elsevier España, S.L.U. All rights reserved.

  2. Preliminary Characterization of the Liquid Discharge of the Mexico Hospital; Caracterizacion Preliminar de la Descarga Liquida del Hospital Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez Rojas, A

    2001-07-01

    constituye un grave problema a nivel nacional. En este trabajo se realiza una caracterizacion preliminar de la descarga liquida del Hospital Mexico. Para ello se analizaron diferentes puntos de vertido dentro de la institucion, ellos son : Lavanderia, cocina central, Laboratorio Clinico, Rayos X, Laboratorio de Biomasa, Morgue y la descarga final del hospital. Esto con el fin de conocer el manejo de los desechos liquidos en el centro de salud, la calidad sanitaria de estos vertidos y su influencia en las aguas crudas del Hospital Mexico en el cuerpo receptor. Para este estudio primero se coordino con el personal de cada departamento para conocer sobre el manejo y tipo de residuos liquidos que son descargados al sistema de tuberias. Posteriormente se realizaron las pruebas fisico-quimicas y biologicas con base en dos muestreos compuestos realizados los dias 26 de octubre y 4 de noviembre de 1998. Entre las pruebas realizadas se tienen: pH, DBO, DQO, SAAM, Grasas y Aceites, Temperatura, Nitrogeno y Coliformes Fecales, dependiendo de las caracteristicas de su punto de procedencia. Al final del estudio, se evaluaron los resultados obtenidos para cada punto de vertido estudiado y luego se analizo la influencia de estos focos sobre la calidad de las aguas crudas del hospital, las cuales descargan en una quebrada localizada al costado noroeste de las instalaciones. Los resultados obtenidos permiten conocer preliminarmente la caracterizacion de la descarga liquida del Hospital Mexico y lo catalogan como una fuente de contaminacion. El Hospital requiere de una planta de tratamiento biologica para aquellos vertidos biodegradables, y de un sistema de tratamiento quimico para tratar ese tipo de productos, que son utilizados en los procesos propios de cada departamento; ademas se requiere tomar en cuenta medidas de reduccion de contaminacion que disminuyan la cantidad de desechos desde la fuente. (Author)

  3. Documentos audiovisuales y prácticas laborales en las Bibliotecas Populares de La Plata: un estudio de caso Audiovisual documents and work practices in Popular Libraries of La Plata: a case study

    Directory of Open Access Journals (Sweden)

    Javier Planas

    2007-12-01

    Full Text Available Se describe y analiza el tratamiento que los documentos audiovisuales reciben, a través de las políticas de desarrollo de colecciones, los procesos técnicos y los servicios, en una muestra de bibliotecas populares de la ciudad de La Plata. Se señala la existencia de un panorama común a la mayor parte de las bibliotecas. Se destacan las características de dos instituciones que se constituyen como excepciones a esta generalidad.The treatment received by audiovisual documents is described and analyzed in relation with the policies of collection development, technical processes and services, in a sample of popular libraries located in La Plata City. The existence of a common picture in the great majority of these libraries is corroborated. The characteristics of two of the libraries are noted as exceptions to the general situation.

  4. La construccion social del paisaje cultural. Entre el Paseo del Bosque y el Estadio de Estudiantes de la Plata

    Directory of Open Access Journals (Sweden)

    Mabel Irma Contin

    2011-01-01

    Full Text Available Este artículo presenta los resultados de una investigación sobre las transformaciones y tensiones en el espacio público central cuyo propósito ha sido descubrir, finalmente, los valores en juego en la gestión contemporánea del paisaje cultural urbano. Dicha investigación toma como caso de estudio la ciudad de La Plata (Argentina y su principal parque urbano, el Paseo del Bosque. Éste contiene en uno de sus bordes al estadio de fútbol del Club Estudiantes de La Plata, uno de los equipos emblemáticos de la ciudad, cuyo proyecto de renovación ha originado un conflicto urbano de una dificultad sin precedentes.

  5. Diagnóstico estructural de la cadena de valor del turismo de reuniones en La Plata

    OpenAIRE

    Lauman, María Victoria

    2015-01-01

    En el transcurso de la obra se realiza un estudio y una evaluación sobre el estado actual en que se encuentran cada uno de los componentes de la cadena de valor de la cual depende el turismo de reuniones en la ciudad de La Plata, para tomar conocimiento de la oferta turística de reuniones existente en la ciudad y poder contribuir a su mejora. Facultad de Ciencias Económicas

  6. The need of alkalinity determination in the characterization of rain; Necesidad de la determinacion de la alcalinidad en la caracterizacion de la lluvia

    Energy Technology Data Exchange (ETDEWEB)

    Pal Verma, Mahendra [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1998-01-01

    In this paper is presented the alkalinity determination of the carbonic species in the rain waters by the Gran titration method. The alkalinity values obtained by this method in low electric conductivity waters are fairly reliable. Also, the existing studies on the characterization of acid rains, are discussed. [Espanol] En este trabajo se presenta la medicion de la alcalinidad y la determinacion de las especies carbonicas en las aguas de lluvia por el metodo de la titulacion de Gran. Los valores de alcalinidad obtenidos por este metodo en las aguas de baja conductividad electrica son bastante confiables. Asimismo, se discuten los estudios existentes sobre la caracterizacion de la lluvia acida en la republica mexicana.

  7. A numerical study of the Plata River plume along the southeastern South American continental shelf

    Directory of Open Access Journals (Sweden)

    Felipe M. Pimenta

    2005-12-01

    Full Text Available The Rio de la Plata, one of the largest rivers on Earth, discharges into the ocean waters from basin that covers a large area of South America. Its plume extends along northern Argentina, Uruguay, and southern Brazil shelves strongly influencing the ecosystems. In spite of this, little is known about the mechanisms that control it. Here we report results of simulations with POM carried out to investigate the roles of wind and river discharge in Plata plume dynamics. Different outflows were explored, including an average climatological value and magnitudes representative of La Niña and El Niño. Forcing the model with river discharge the average plume speed was directly related to the outflow intensity. The Plata northward extension varied from 850 to 1550 km and for average discharge a band of low salinity waters formed from the estuary up to 30ºN of South Brazilian Shelf. Upwelling and downwelling winds were applied after 130 days. The distribution of low salinity waters over the shelf was more sensitive to the wind direction than to the river outflow variability. Downwelling winds were very capable of advecting the low salinity signal downshelf. Upwelling winds were efficient in eroding the plume, which was basically detached from the coast by Ekman drift. Abnormal plume intrusions toward low latitudes may be a result of the original plume position coupled with events of persistent strong downwelling favorable winds.O Rio da Prata, um dos maiores rios da Terra, descarrega no oceano águas de uma bacia de drenagem que cobre uma ampla área da América do Sul. Sua pluma extende-se ao longo do norte da Argentina, Uruguay e sul do Brasil influenciando amplamente os ecossistemas costeiros. A despeito disso, pouco se sabe a respeito dos mecanismos que a controlam. Relatamos aqui simulações conduzidas com o modelo POM na investigação do papel dos ventos e da descarga fluvial na dinâmica da pluma do Prata. Descargas com valores médios climatol

  8. Aquatic habitat modifications in La Plata River basin, Patagonia and associated marine areas.

    Science.gov (United States)

    Mugetti, Ana Cristina; Calcagno, Alberto Tomás; Brieva, Carlos Alberto; Giangiobbe, María Silvia; Pagani, Andrea; Gonzalez, Silvia

    2004-02-01

    This paper describes the environmental characteristics and situation of aquatic habitats and communities in southern continental and maritime areas of southeastern South America (Patagonian Shelf GIWA Subregion), resulting from an overall assessment carried out within the framework of a GIWA project, mostly on the basis of publicly available data. The main focus of the analysis was on the current situation of transboundary water resources and anthropogenic impacts. In the inland waters, habitat and community modifications result, principally, from dams and reservoirs built in the main watercourses for hydroelectric power generation and other uses. The transformation of lotic environments into lentic ones have affected habitats and altered biotic communities. In the La Plata River basin, invasive exotic species have displaced native ones. Habitats in the ocean have been degraded, as their biodiversity becomes affected by overfishing and pollution. This article includes a discussion on the causal chain and the policy options elaborated for the Coastal Ecosystem of Buenos Aires province and the Argentinean-Uruguayan Common Fishing Zone, where fishing resources are shared by both countries.

  9. SÍNTESIS IN SITU DE NANOPARTÍCULAS DE PLATA SOBRE FIBRAS DE FIQUE

    Directory of Open Access Journals (Sweden)

    Sergio Ovalle

    2014-07-01

    Full Text Available Se realizó la síntesis de un material nanocompuesto mediante la deposiciónin situ de nanopartículas (NPs de plata sobre fibras de Fique. La influencia de parámetros experimentales, como concentración del precursor, concentración del agente reductor y tiempos de inmersión de las fibras en la solución del precursor y del agente reductor, se evaluó en términos de recubrimiento, tamaño y dispersión del nanomaterial sobre la superficie. Los nanocompositos fueron caracterizados mediante espectroscopia de reflectancia difusa UV-Vis (RD, microscopía electrónica (FESEM y difracción de rayos X (DRX. El control de los parámetros experimentales mencionados permitió obtener un material que exhibe recubrimiento uniforme y completo de NPs sobre la superficie y tamaños promedio de NPs de 40 nm. 

  10. Prospects of approach and characterization of Mar del Plata peri-urban, Argentina

    Directory of Open Access Journals (Sweden)

    Rosana Ferraro

    2013-10-01

    Full Text Available In Latin America in general, and in Argentina in particular, city growth without prior planning results in the formation of highly complex peri-urban areas. The urban-rural analysis based on the traditional model of country-city dichotomy is not enough to explain the processes that occur in these cities. On the basis of prior studies conducted in the peri- urban of Mar del Plata, Argentina, this paper aims to : a characterize the peri-urban by studying its functions throughout history, b propose a rereading for its further analysis through the complex systems theoretical-methodological approach, and c describe the main areas that account for its special heterogeneity and complexity. From an integral viewpoint, and taking the physical, sociocultural, productive, urban- residential and digester subsystems into account, the analysis of the peri-urban allowed to define areas with differential characteristics. Such areas admit higher disintegration in more detailed scales, making it easy to understand their operation and their problems. In conclusion, the complex systems approach results appropriate to promote the development of management strategies in areas as heterogeneous as the peri-urban.

  11. Determination of risk indices in quarries of two basins in La Plata Municipality Argentina

    International Nuclear Information System (INIS)

    Cabral, M.; Crincoli, A.; Gimenez, J.; Hurtado, M.

    2004-01-01

    Soil extraction is one of the main causes of degradation of this resource in Buenos Aires province. In La Plata municipality, soil is extracted at different depths for a variety of uses. Deep soil extraction creates quarries which have a negative impact on the environment, the landscape, the real estate value and life quality. The inundated quarries become precarious swimming places where many people have drowned. When the quarries are used as garbage dumps, they can concentrate disease vectors or pollute groundwater through their leachates. The face-cuts are often near vertical and can be susceptible to collapse. The methodology to calculate the risk index is based on the hypothesis that risk variables can be identified, individually assessed and combined in such a way that they would provide a numerical value reflecting the likelihood of accidents or diseases occurring as a consequence of quarry's presence. The general objective of the project is to obtain an index for the quarries of the studied basins aimed at warning local authorities and affected persons about the sites where protection and reclamation measures are more urgently needed. The values obtained are represented on a map showing the risk class of each quarry. It is concluded that the methodology is useful to determine priorities and can prove a good management tool for those involved in this problem [es

  12. Game at the old age, stories of old men from Mar del Plata

    Directory of Open Access Journals (Sweden)

    Débora Paola Di Domizio

    2012-11-01

    Full Text Available This text attempts to problematise the topic of game at the old age. The author used the description of an experiment conducted in the city of Mar del Plata in the context of teacher education and whose participants were senior citizens and students in fourth year of their course of studies in Teacher Education in Physical Education in the province. The theoretical framework is provided by the bibliography studied in a Game Theory Seminar attended by the author in her journey to achieve a postgraduate degree as Master in Body Education and by other studies relevant to gerontology. Furthermore, the data obtained through interviews in the fieldwork described here is the input needed to analyze both conceptualizations about old age and aging and the ideas and preconceptions about game in senior citizens. This data also allows the analysis of the games of yesterday and today and the multiplicity of meanings they acquire at the old age, from the voices of the protagonists of the experience

  13. Less is more: bondades de lo breve en el Río de la Plata

    Directory of Open Access Journals (Sweden)

    Julio Prieto

    2014-06-01

    Full Text Available Las famosas palabras del prólogo de El jardín de senderos que se bifurcan condensan una poética narrativa que no sólo podemos considerar emblemática de uno de los autores seminales del siglo XX –Jorge Luis Borges– sino que también informa una de las líneas de escritura más fructíferas de la literatura del Río de la Plata: aquella que cifra un decoro literario en la eficacia de la brevedad. En esa tradición se cuentan algunas de las obras más significativas de esa literatura, desde la microtextualidad de los prólogos, “resúmenes y comentarios” de Borges, a los relatos breves y viñetas humorísticas de Julio Cortázar, Cristina Peri Rossi, Luisa Valenzuela y Ana María Shua.

  14. Mesoproterozoic evolution of the Rio de la Plata Craton in Uruguay: at the heart of Rodinia?

    DEFF Research Database (Denmark)

    Gaucher, Claudio; Frei, Robert; Chemale, Farid

    2011-01-01

    Mesoproterozoic volcanosedimentary units and tectonic events occurring in the Ri´o de la Plata Craton (RPC) are reviewed. A belt consisting of volcanosedimentary successions exhibiting greenschist-facies metamorphism is exposed in the eastern RPC (Nico Pe´rez Terrane) in Uruguay. The Parque UTE...... and top, and Conophyton-bearing limestones and massive dolostones in the middle. A U–Pb LA-ICP MS zircon age of 1,433 ± 6 Ma is reported here for lapilli-tuffs at the base of the Mina Verdu´n Group (Cerro de las Vi´boras Formation). This age shows that the Mina Verdu´n Group immediately postdates...... the Sarandi´ del Yi´ megashear. We report a U–Pb LA-ICP MS zircon age (upper intercept) of 3,096 ± 45 Ma for metatonalites of the La China Complex (Nico Pe´rez Terrane), which yield a lower intercept age of 1,252 Ma. A proto-Andean, Mesoproterozoic belt is envisaged to account for abundant Mesoproterozoic...

  15. Empresarialidad y desarrollo local en la región rural periurbana de La Plata Entrepreneurship and local development in the peri-urban rural region of La Plata

    Directory of Open Access Journals (Sweden)

    Rossana Cacivio

    2012-01-01

    Full Text Available This article is focused on analytical thinking of the participants of a entrepreneurial development programme in the peri-urban rural region focus in the city of La Plata. The programme it started with an action of the extension of the Universidad Nacional de la Plata [Olmos Emprende], the development led to the joint and more programs national and provincial. The first objective is to describe the conditions in the entrepreneurship in Latin America and contextualize the experience presented. Afterwards a consideration of the local territorial context that would have facilitated the participation in the program, taking into account two regional areas: On the one hand the periurban rural region in general and on the other hand, a series of local dimensions that, in addition to factors techno-economic state and regulatory frameworks, include social and cultural circumstances. The question that crosses the text, focuses on the location of the entrepreneurship in the territory, focusing on their possibilities of local development. We observed the situations of interface between various regional actors, between groups of citizens, various state agencies and the diverse participation also of private agentsEl artículo se centra en la reflexión analítica de los participantes de un programa de desarrollo emprendedor en la Región Rural Periurbana centrada en el municipio de La Plata. El programa partió de una acción de extensión de la Universidad Nacional de La Plata [Olmos Emprende], cuyo desarrollo derivó en la articulación con programas más abarcativos de orden nacional y provincial. El primer objetivo es describir las condiciones específicas en las que se desarrolla la empresarialidad en América Latina y contextualizar la experiencia presentada. Posteriormente se hace una consideración del contexto territorial local que habría facilitado la participación en el programa teniendo en cuenta dos ámbitos regionales: por un lado la Regi

  16. Síntesis de nanopartículas de plata por ablación láser funcionalizadas con bicapa de grafeno

    OpenAIRE

    Damián Briones, María Angelica; Damián Briones, María Angelica; Damián Briones, María Angelica

    2015-01-01

    En este trabajo se obtuvo nanopartículas de plata por ablación laser para luego ser funcionalizadas con bicapa de grafeno, mediante la técnica de evaporación. Para la obtención de las nanopartículas de plata se usó un “target” de plata al 99,9% de pureza el cual fue colocado dentro de un recipiente que contenía agua ultrapura, sobre él se incidió un láser de Nd:AYG modelo Brillant, en el cual se pudo controlar la fluencia, longitud de onda, el medio y el tiempo de ablación. Para la obte...

  17. Riesgo de establecimiento del gasterópodo dulceacuícola invasor Melanoides tuberculatus (Thiaridae en el Río de la Plata (Argentina-Uruguay Colonization risks of the invading freshwater gastropod Melanoides tuberculatus (Thiaridae in Río de la Plata (Argentina-Uruguay

    Directory of Open Access Journals (Sweden)

    Diego E. Gutiérrez-Gregoric

    2010-08-01

    Full Text Available Melanoides tuberculatus es un gasterópodo cosmopolita que ha invadido y se ha establecido en casi todos los países del continente americano, desconociéndose en la mayoría de los casos el origen de su introducción. En este trabajo se menciona el riesgo de establecimiento de esta especie en áreas de influencia del Río de la Plata como consecuencia de su registro en acuarios de la ciudad de La Plata (Buenos Aires, Argentina dedicados a la venta de flora y fauna limnética. A principios de 2009, la especie fue identificada a partir de 26 ejemplares procedentes de un comercio, siendo éste el registro más austral de la especie para una localidad de la cuenca del Plata. Revisiones posteriores en 3 locales comerciales de la ciudad confirmaron la presencia de la especie en 2 de ellos. Dicha presencia se relacionó con la adquisición de plantas ornamentales por parte de los establecimientos. La identificación del gasterópodo en la ciudad de La Plata debe considerarse cuidadosamente, debido a las posibles consecuencias que tendría la liberación accidental de este molusco en el Río de la Plata en lo relacionado con el desplazamiento de fauna local y salud pública.Melanoides tuberculatus is a cosmopolitan gastropod that has invaded and has now spread into most countries of the American continent. Introduction pathways remain unknown in most cases. This work draws attention on the colonization risks of this species in the Río de la Plata area as a consequence of its record in flower and pet shops - in the city of La Plata (Buenos Aires, Argentina - in which limnic species are sold. The species was identified at the beginning of 2009 within a lot of 29 specimens from a shop, and this is the southernmost record of this species in the Plata Basin. Subsequent surveys in 3 commercial shops in the same city revealed its presence in 2 of them. This was related to the purchase of ornamental plants by the shops. Identification of this species in the

  18. In Memoriam, En Homenaje a los Drs. Rafael Barberi Zamorano y Ernesto Plata Rueda

    Directory of Open Access Journals (Sweden)

    Eduardo Alvarez P.

    1992-09-01

    Full Text Available

    Y se marcharon…. Partieron como si existiera un acuerdo previo para realizar el encuentro definitivo en la eternidad. Después de una ejemplar y fructífera existencia, plena de múltiples realizaciones, se hace indispensable el goce de la paz eterna. Partieron, pese nos dejaron la huella de dos vidas que marcharon paralelamente con destino hacia un mismo objetivo, el niño colombiano.

    Este ser, la razón primera de nuestra especialidad, incapaz de mentir, inocente, indiferente ante lo bueno y lo malo, indefenso, amante del mundo que lo rodea, tierno y cariñoso. Fueron dos ilustres colombianos que caminaron por el mismo sendero, con diferente fin. Ernesto Plata Rueda en el campo de la investigación y la docencia y Rafael Barberi Zamorano en la dirección y administración del Hospital de la Misericordia, cuna de la pediatría en nuestra patria y recurso en salud en favor de las clases sociales menos favorecidas.

    Como extraña y feliz coincidencia el destino los ubicó a pocos metros de distancia el uno del otro, lo que facilitó para que sus labores fueran siempre acordes y se desarrollaran en perfecta armonía por cerca de tres lustros; esta circunstancia permite al final presentar a las generaciones futuras toda esa inmensa gama de realizaciones que hoy quedan en los campos de la salud y la ciencia. Tuve la inmensa fortuna de ser testigo cercano del diario desarrollo de sus actividades y es por esta razón por la cual no puedo retirar de la mente la capacidad de trabajo, dedicación y amor a los pacientes, al Hospital, de Rafael Barberi un gran filántropo, hombre tímido y sencillo, virtudes que lo hicieron más grande y admirable; no le faltó jamás el valor suficiente dentro de la mayor honestidad y respeto para convertirse en aguerrido defensor de la Institución y de sus colaboradores, también fué geperoso y bondadoso al otorgar el perdón y el olvido a sus ocasionales detractores.

    Ernesto Plata Rueda, el

  19. Pesticide impact study in the peri-urban horticultural area of Gran La Plata, Argentina.

    Science.gov (United States)

    Mac Loughlin, Tomás M; Peluso, Leticia; Marino, Damián J G

    2017-11-15

    Vegetable production systems are characterized by intense pesticide use, yet the effects on the surrounding environment are largely unknown and need to be studied. Given this knowledge gap, the objective of this work is to determine the impact of horticulture on a representative watercourse by conducting an integrated study of the occurrence and concentration of pesticides in bottom sediments and their relation to lethal and sublethal effects on benthic fauna. Two sampling campaigns were conducted during seasons of low and high pesticide application in five sites along the Carnaval creek, located in the peri-urban area of La Plata City (Buenos Aires, Argentina). The samples were tested for 36 pesticide compounds by GC-MS and LC-MS, and whole-sediment laboratory toxicity tests were performed using the native amphipod Hyalella curvispina. The results showed a general but variable distribution in the concentrations detected along the stream. For each sampling campaign (first/second), the total pesticide loads, measured as the sum of herbicides, insecticides and fungicides, were 1080/2329, 3715/88, and 367/5ngg -1 dw, respectively. Lethal and sublethal effects were observed in both sampling campaigns. In order to correlate both sets of results, data were assessed by multivariate analysis, including principal component analysis. The observed toxicity was considered to be mainly due to insecticides; thus, horticultural practices have an impact on nearby watercourses and can potentially endanger the benthic fauna. This is the first study in Argentina to assess the impact of pesticides on aquatic environments close to horticultural production areas. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Crecimiento y nutrición en preescolares de la ciudad de La Plata

    Directory of Open Access Journals (Sweden)

    Ranieri, José

    2001-01-01

    Full Text Available El objeto del presente trabajo es determinar el estado nutricional en una población proveniente del área urbanomarginal de La Plata compuesta por 215 niños de ambos sexos, de edad preescolar (2-5 años. Se relevaron las variables peso/edad; talla/edad y perímetro cefálico/edad incorporando además la variable knemométrica (tomada con pie de rey desde el punto superior de la rótula hasta el punto más bajo del talón. Los datos se procesaron mediante pruebas de Kolmogorov-Smirnov y Levene, análisis de varianza (ANOVA, correlación y regresión. Se calcularon diferencias porcentuales relativas entre medias (PDM. La muestra presentó distribución normal. Los puntajes Z indicaron valores entre -0.3 y 1.6. El ANOVA mostró para el factor edad diferencias significativas en todas las variables analizadas y para el factor sexo sólo en perímetro cefálico. Las correlaciones entre la variable knemométrica con las restantes variables fueron altamente significativas. Los resultados obtenidos permiten determinar que la población analizada presenta un estado nutricional óptimo respecto de los estándares del NCHS. La evaluación knemométrica constituye un buen indicador del crecimiento, dada su correspondencia con aquellos usualmente empleados.

  1. Integrating Geological map of the Plata Basin and adjacent areas: release Bulletin

    International Nuclear Information System (INIS)

    Preciozzi, F.; Spoturno Pioppo, J.; Medina, E.

    2001-01-01

    During the 1st Meeting of the Geological Surveys of the Southern Cone Countries, held in the city of Porto Alegre (Rio Grande do Sul - Brazil) in November 1995, it was born the idea of ​​a set of activities that it had aimed at developing integration , technical cooperation and scientific exchange between these institutions, resulting in a concrete proposal in order to develop a map of geological, metallogenic and hydrogeological basins of the Parana and Plata integration; which provide the basic information needed for the further development of mineral resources maps approach to groundwater, gold, ornamental stones, industrial minerals and precious stones; the development of exchange activities in the area of ​​the environment and the creation of a data bank of geological and mining of the countries involved in the program. This intention of working together was presented to SGT2, Theme of Geology and Mineral Resources MERCOSUR Commission, at its first meeting, held in Buenos Aires - Argentina, in April 1996, with the aim of transforming it into an official activity of this Commission, time that the delegations of the four States-Party endorsed the proposal. These opportunities were discussed and established parameters and standards for the execution of the works to be developed in the area between the parallel of 14oS and 38oS and meridians 44oW and 68oW (Figure 1), covering approximately 5,800,000 Km2 continental area, scale 1: 2,500,000, covering the entire basin of the River Plate. geological one, one and one hydrogeological mineral resources, plus a database of mineral resources, which serve as a source of information for the map of mineral resources: the generation of three maps was established as a goal. The official name for this project was established Maps

  2. Síntesis electroquímica de nanopartículas de plata en presencia de un surfactante neutro

    OpenAIRE

    Blandón, Lucas; Vázquez, Mario V.; Boannini, Elisa; Ballarin, Bárbara

    2015-01-01

    Muchas de las aplicaciones de las nanopartículas de platase encuentran en el área de la medicina como agentesantimicrobianos. Para evaluar la actividad antimicrobianade estos materiales, es importante garantizar que se encuentran estables y que los agentes estabilizantes seanbiocompatibles. Entre los métodos propuestos para lasíntesis de nanopartículas de plata se encuentran losmétodos electroquímicos, que han mostrado tener ventajasgracias a la facilidad para controlar las variables desíntes...

  3. Sistemas de calidad en turismo. Posibilidades y restricciones de su implementación en Mar del Plata

    OpenAIRE

    Castellucci, Daniela I.

    2011-01-01

    La tesis tiene como objetivos indagar en las empresas hoteleras, gastronómicas y de balnearios de la ciudad de Mar del Plata (Argentina), el nivel en que se encuentra su cultura de la calidad; e identificar cuáles son los factores determinantes en la toma de decisión para la implementación de Sistemas de Gestión de Calidad. Desde un enfoque cualitativo, y tomando la modalidad de estudio de casos múltiples, se analizan en dieciocho empresas de servicios turísticos, la cultura organizacional, d...

  4. 21Pb dating of sediments in a heavily contaminated drainage channel to the La Plata estuary in Buenos Aires, Argentina

    International Nuclear Information System (INIS)

    Di Gregorio, D.E.; Fernandez Niello, J.O.; Huck, H.; Somacal, H.; Curutchet, G.

    2007-01-01

    Concentrations of 21 Pb and 137 Cs in sediment samples collected from two cores at a drainage channel to the La Plata river estuary in Buenos Aires, Argentina, were measured using ultralow-background detection systems. The 21 Pb data were used to determine the rate of sediment accumulation of the sites. These results were correlated with some heavy metal (chromium and lead) concentrations of the samples in an attempt to characterize the historical input of contaminants due to the industrial development, which has taken place in this area over the last century. The 137 Cs measurements demonstrate that cesium dating is not adequate in regions of the southern hemisphere

  5. Evaluación "In vitro" e "in vivo" de la seguridad de nanopartículas de plata

    OpenAIRE

    Ávalos Fúnez, Alicia

    2017-01-01

    El rápido desarrollo de la nanotecnología ha abierto la puerta a la obtención de productos y aplicaciones innovadoras para una amplia gama de sectores de la industria y el consumo. Se estima que de todos los nanomateriales utilizados en productos para el consumo, las nanopartículas de plata (AgNPs) son las que tienen un mayor grado de comercialización. Sin embargo, a pesar de las innumerables aplicaciones que presentan, poco se sabe sobre su toxicidad, planteando un riesgo para la salud human...

  6. Inventario de fuentes puntuales de contaminación potencial del agua subterranea: caso de estudio Mar del Plata

    OpenAIRE

    Massone, Héctor; Corleto, Bárbara; Albornoz, Daniel; Lima, Lourdes; Pertini, Ignacio; Damiano, Fernanda; Barilari, Agustina; Fresta, Paula

    2016-01-01

    La ciudad de Mar del Plata es la cabecera del Partido de General Pueyrredón, tiene una población de 620.000 habitantes y se abastece íntegramente del recurso hídrico subterráneo. Una parte importante del proceso de gestión de este recurso es la prevención de la contaminación; en este sentido, son variadas las metodologías de caracterización de carga contaminante; uno de sus aspectos es el modo de disposición, en el que pueden identificarse fuentes puntu...

  7. Representaciones sobre el aborto : Estudio de jóvenes de sectores pobres de la ciudad de La Plata (2012)

    OpenAIRE

    Caneva, Hernán Andrés

    2012-01-01

    En el presente trabajo se expondrán los avances de un estudio exploratorio de corte cualitativo que estoy realizando con motivo de finalizar mi tesina de grado en la carrera de Lic. Sociología. En dicho estudio me propongo conocer y analizar representaciones acerca del aborto de jóvenes (varones y mujeres) escolarizados de sectores pobres de la ciudad de La Plata durante 2012. La hipótesis de trabajo que orienta el estudio indica que la integración en espacios de socialización tales como l...

  8. Moessbauer studies of one representative hydromorphic soil of the coastal area of the Rio de La Plata

    Energy Technology Data Exchange (ETDEWEB)

    Guichon, B. A. [Universidad Nacional de La Plata, Instituto de Geomorfologia y Suelos (Argentina); Desimoni, J.; Mercader, R. C., E-mail: mercader@fisica.unlp.edu.ar [Universidad Nacional de La Plata, Departamento de Fisica, IFLP-CONICET, Facultad de Ciencias Exactas (Argentina); Imbellone, P. A. [Universidad Nacional de La Plata, Instituto de Geomorfologia y Suelos (Argentina)

    2010-01-15

    In the present work, we have applied Moessbauer spectroscopy as well as the traditional chemical analyses to assess the contents of different states of Fe in oxides and hydroxides in an Entisol soil from the Argentine coastal plain of the Rio de La Plata. Tentative assignments for the different Fe ion sites are proposed. Our findings show that the isomer shift and quadrupole splitting are sensitive to the changes detected in the Fe{sup 2+} contents of the soluble phase while others remain constant within the experimental uncertainties.

  9. Selección de dormideros por el estornino pinto (Sturnus vulgaris) en La Plata, Buenos Aires, Argentina

    OpenAIRE

    Girini, Juan Manuel; Palacio, Facundo Xavier; del Huerto, María del C.; Kuzmanich, Nicolás

    2016-01-01

    El Estornino Pinto (Sturnus vulgaris) es un ave introducida en Argentina que establece dormideros comunales durante la época no reproductiva. A pesar de ser una de las especies invasoras más perjudiciales del mundo, se conoce muy poco acerca de su ecología en Argentina. En este trabajo se caracterizaron los dormideros comunales del Estornino Pinto en la ciudad de La Plata con el objetivo de evaluar la selección del sitio de dormidero por parte de la especie. Se encontró un total de 34 dormide...

  10. Selección de dormideros por el Estornino Pinto (Sturnus vulgaris) en La Plata, Buenos Aires, Argentina

    OpenAIRE

    Girini, Juan M; Palacio, Facundo X; del Huerto, María del C; Kuzmanich, Nicolás

    2014-01-01

    El Estornino Pinto (Sturnus vulgaris) es un ave introducida en Argentina que establece dormideros comunales durante la época no reproductiva. A pesar de ser una de las especies invasoras más perjudiciales del mundo, se conoce muy poco acerca de su ecología en Argentina. En este trabajo se caracterizaron los dormideros comunales del Estornino Pinto en la ciudad de La Plata con el objetivo de evaluar la selección del sitio de dormidero por parte de la especie. Se encontró un total de 34 dormide...

  11. Las localidades menores del sur de Mar del Plata desde una perspectiva demogeográfica (1991-2001

    Directory of Open Access Journals (Sweden)

    Sofía Estela Ares

    2008-01-01

    Full Text Available En relación con el crecimiento demográfico de las localidades ubicadas al sur de Mar del Plata (Partido de General Pueyrredon el problema es establecer el aporte de los saldos vegetativos y de los saldos migratorios. Las bases de datos censales permiten la aproximación indirecta al comportamiento vegetativo; con respecto a las migraciones, no es posible calcular saldos de movilidad. Los resultados se obtuvieron mediante el procesamiento cuantitativo de datos censales y muestran un proceso de envejecimiento en las localidades mencionadas y la probable preeminencia del componente migratorio en el crecimiento demográfico.

  12. Urban transformations in the district of La Plata since the nineties. A compact or a diffuse city model?

    Directory of Open Access Journals (Sweden)

    Julieta Constanza Frediani

    2006-01-01

    Full Text Available In the last decade several studies done on the transformation of the city from compact to more scattered and fragmented have shown the concern for the effects the open and scattered city may have upon the environment. Although we consider that the urban models, "compact" and "diffuse", actually cannot be found in isolation, they are used to represent the extremes that relate the model of our city with these two models. The purpose of the present paper is to recognize in La Plata District, the behavioral pattern variable that causes the territorial conflicts in each of the models.

  13. Reptiles escamosos (Squamata del Pleistoceno Medio del Norte de la ciudad de Mar del Plata (provincia de Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Santiago Brizuela

    2015-05-01

    Full Text Available In this study, we describe two fossil remains of squamate reptiles found in Middle Pleistocene outcrops at the northern marine cliffs of the city of Mar del Plata (Buenos Aires province. The specimens were found forming a taphocenosis with remains of other microvertebrates (amphibians, mammals and birds. The reptiles recognized in the association are represented by remains of an undetermined colubrid, and the anguid Ophiodes sp. This latter finding represents the first fossil record for the family Anguidae exhumed in Argentina.

  14. Equilibrios de precipitación. Influencia del pH sobre la solubilidad del acetato de plata. Problema interactivo.

    OpenAIRE

    Milla González, Miguel

    2015-01-01

    Se estudia como influye la variación del pH en la solubilidad de una sal cuya parte aniónica es una base débil. Es el caso del acetato de plata. Mediante una animación se muestra el desplazamiento del equilibrio hacia una mayor solubilización. El paso siguiente es encontrar una expresión sencilla que relaciona la solubilidad con el pH y se representa gráficamente dicha función mediante una hoja de cálculo.

  15. Turismo de congresos y reuniones en la ciudad de La Plata: Estado actual, tendencias y posibilidades de desarrollo

    OpenAIRE

    Herrera, Leandro Javier

    2014-01-01

    Año a año Argentina es elegida como sede de todo tipo de reuniones, una modalidad turística vista como una actividad económica rentable que crece sostenidamente a nivel mundial y nacional. El siguiente trabajo de investigación describe la situación actual de La Plata como ciudad sede de este fenómeno, los diferentes eventos realizados durante el año 2013 y características generales del consumidor principal de este segmento. Se realiza una conceptualización y contextualización del turism...

  16. Construcción de un edificio bajo la figura del fideicomiso en Mar del Plata, en 2008

    OpenAIRE

    Fagioli, Francisco

    2008-01-01

    Se desarrolló el caso particular de la construcción de un edificio de departamentos en la ciudad de Mar del Plata proponiendo la implementación de la figura del Fideicomiso y se analizaron las ventajas que ello representa para los Fiduciantes. El proyecto incluyó un análisis del mercado y comercialización de los servicios, la viabilidad técnica y la de gestión, la enumeración de inversiones y los requisitos necesarios para cumplir con las legislaciones vigentes, el análisis ...

  17. Nanopartículas de plata con potenciales aplicaciones en materiales implantables: síntesis, caracterización fisicoquímica y actividad bactericida

    OpenAIRE

    Flores, Constanza Y.

    2014-01-01

    El objetivo general del presente Trabajo de Tesis fue la preparación y caracterización de superficies sólidas modificadas con nanopartículas de plata con potenciales aplicaciones en Biomedicina. Para esto se optimizó el método de síntesis de nanopartículas de plata (NPs Ag) recubiertas con citrato, obteniendo NPs Ag monodispersas de 6 ± 2 nm de diámetro recubiertas con citrato y estables en medios acuosos. Asimismo, se estudió la inmovilización de estas NPs Ag sobre superficies de Ti/TiO2, en...

  18. Variación de la recarga entre La Plata y Santa Isabel (provincias de Buenos Aires y La Pampa - Argentina) : Propuesta metodológica

    OpenAIRE

    Hernández, Mario Alberto; Giai, Santiago B.

    1996-01-01

    Se analiza la recarga potencial de aguas subterráneas sobre un perfil entre La Plata y Santa Isabel (Buenos Aires y La Pampa). El mismo tiene la particularidad de ser perpendicular a las isohietas, extendiéndose desde una zona húmeda lindante con el río de la Plata, hasta otra de fuerte aridez y continentalidad, unos 900 km al Oeste. Algunos de los factores influyentes en el monto de la recarga tienen el mismo valor en todo el perfil, alcanzando su intervención igual peso en todas las local...

  19. Escenario de la presencia italiana en La Plata : El edificio del Banco de la provincia de Buenos Aires como objeto de análisis

    OpenAIRE

    Carbonari, Fabiana Andrea; Grandis, María Belén de

    2015-01-01

    El presente artículo se inscribe en el plan de trabajo de la Beca Interna de Entrenamiento en Investigación de la FAU denominada Italianos en la ciudad de La Plata. El caso del Banco Provincia de la ciudad de La Plata que, durante el ciclo lectivo 2015 desarrolla la Arq. María Belén de Grandis con dirección de la Esp. Arq. Fabiana Carbonari. La misma tiene por objetivo realizar el estudio histórico sistemático del Banco de la Provincia de Buenos Aires. En ese sentido, propone analizar las tra...

  20. Conducta Innovadora en el Sector Industrial: El caso de Pequeñas y Medianas Empresas en Mar del Plata, Argentina (Innovating behavior in the Industrial Sector: Small and medium size enterprises in Mar del Plata, Argentina

    Directory of Open Access Journals (Sweden)

    Lucía Mercedes Mauro

    2012-12-01

    Full Text Available El cambio tecnológico es central en una estrategia de desarrolloeconómico endógeno, y su abordaje exitoso por partede las empresas requiere de un entorno a partir del que sepromueva y acompañe dicho proceso. El objetivo del estudioes comprender, desde una óptica territorial, la conducta innovadorade empresas industriales. Para ello se analiza el caso decuatro PYMES en segmentos con alto potencial de crecimientoeconómico de la ciudad de Mar del Plata (Argentina en el períodopost-convertibilidad. Se concluye que estas empresas tienenun marcado perfil innovador, aún cuando no se encuentraconsolidado el sistema de innovación local, falta de personalcon las competencias necesarias para llevar adelante el cambiotecnológico, y se observan desconexiones entre el sectorpúblico y el privado.   ABSTRACT Technological changes are paramount for an endogenous economicdevelopment programs, and require that companies developingit operate in an environment promoting and nurturing suchprograms. This study´s goal is to understand the innovation behaviorof industrial companies from a territorial point of view. To thatend we analyzed four SMEs operating, in a high economic growthsegment after the conversion period in Mar del Plata, Argentina.It was deduced that said companies possess an innovative profile(even despite the fact that the local innovation support system isnot fully consolidated, lack personnel with the appropriate knowledgeto pursue technological changes, and there are mismatchesbetween the private and public sectors.

  1. Los ejemplares tipo de Dryopidae, Elmidae, Limnichidae y Psephenidae (Coleoptera: Byrrhoidea, depositados en la colección del Museo de La Plata The types of Dryopidae, Elmidae, Limnichidae and Psephenidae (Coleoptera: Byrrhoidea housed at the Museo de La Plata

    Directory of Open Access Journals (Sweden)

    Liliana A. Fernández

    2004-07-01

    Full Text Available Se examinaron los ejemplares tipo depositados en la colección de la División Entomología del Museo de La Plata, pertenecientes a diversas especies nominales de Byrrhoidea: Dryopidae (1 especie, 1 ejemplar tipo, Elmidae (4, 9, Limnichidae (29, 47 y Psephenidae (1, 2. El material tipo fue estudiado por los siguientes autores: Pic, Spangler, Spangler & Brown, Spangler & Perkins, Spangler & Santiago, Spilman y Wooldridge. Para cada taxón se indica la publicación original, datos de colección y condición del material.The types of species of Byrrhoidea (Coleoptera housed in the collection of the División Entomología of Museo de La Plata were examined and listed. They belong to 35 species distributed in the families Dryopidae (1 species, 1 type, Elmidae (4, 9, Limnichidae (29, 47 and Psephenidae (1, 2. The types were described by Pic, Spangler, Spangler & Brown, Spangler & Perkins, Spangler & Santiago, Spilman, and Wooldridge. For each taxon, complete information about categories of types, reference original descriptions, collection data and specimen condition are given.

  2. La empleabilidad y los beneficiarios del Seguro de Capacitación y Empleo en Mar del Plata Employability and beneficiaries of the Training and Employment Insurance in Mar del Plata

    Directory of Open Access Journals (Sweden)

    Ana Julia Atucha

    2011-12-01

    Full Text Available El objetivo de este documento es analizar si la participación de los beneficiarios del Partido de General Pueyrredon en el Seguro de Capacitación y Empleo implicó mejoras en su empleabilidad. En particular, se examinan las relaciones entre formación y empleo de este colectivo, como aproximación a la medición del impacto de esta política de mercado de trabajo en Mar del Plata. La información utilizada se basa en la "Encuesta de Informalidad y Beneficiarios de Programas Sociales" en el aglomerado, llevada a cabo en octubre de 2009 por el Grupo Estudios del Trabajo de la Facultad de Ciencias Económicas y Sociales de la Universidad Nacional de Mar del Plata, en el marco de un proyecto en convenio con la OIT. Esta fuente primaria fue complementada por entrevistas telefónicas a destinatarios seleccionados. El acercamiento se efectuó a través de una exploración de las trayectorias formativas seguidas por los destinatarios, de la valoración que ha tenido la capacitación respecto a la mejora sobre su empleabilidad y de la tarea de vinculación entre demandantes y oferentes que realiza la Oficina de Empleo. Entre los principales resultados se detectaron gran proporción de beneficiarios sin una trayectoria formativa que los califique sobre un oficio, percepciones negativas respecto a su empleabilidad y situaciones de inactividad. El documento deja planteada la necesidad de optimizar las tareas de orientación y vinculación al mercado de trabajo para mejorar la situación del grupo bajo análisis.This paper is aimed to analyze whether the participation of beneficiaries in the Training and Employment Insurance improved their employability. In particular, the relationship between training and employment of this group, as an approach to measuring the effect of this labor market policy in Mar del Plata, will be examined. The information come from the "Survey of Informality and Beneficiaries of Social Programs" collected in Mar del Plata

  3. Nanoparticulas basadas en complejos de Fe(II) con transicion de espin: sintesis, caracterizacion y aplicaciones en electronica molecular

    Science.gov (United States)

    Monrabal Capilla, Maria

    Esta tesis doctoral esta organizada en 5 capitulos y esta destinada al estudio de sistemas de Fe (II) que presentan el fenomeno de la transicion de espin a escala nanometrica. El capitulo 1 contiene una introduccion general sobre materiales moleculares multifuncionales, destacando aquellos ejemplos mas importantes. Por otro lado, se explicara el fenomeno de la transicion de espin, tratando aspectos conceptuales, los antecedentes mas importantes y la situacion actual. En el capitulo 2 se describen los diferentes procesos existentes para la obtencion de diferentes tipos de nanoparticulas. Ademas, se presenta la sintesis y caracterizacion de nanoparticulas del polimero de coordinacion unidimensional [Fe(Htrz)2(trz)]BF4, obtenidas mediante el metodo de micelas inversas. Estas nanoparticulas, con una estrecha distribucion de tamanos centrada alrededor de los 11 nm, presentan una transicion de espin muy abrupta, con un ancho ciclo de histeresis termica de unos 40K. En el capitulo 3 se describe el proceso de modificacion del tamano de las nanoparticulas descritas en el capitulo anterior, llevado a cabo variando la proporcion de surfactante/H2O en el medio. Ademas, con el objetivo de modificar las propiedades magneticas de las nanoparticulas obtenidas en el capitulo 2, se lleva a cabo la sintesis de nanoparticulas de polimeros de la misma familia del [Fe(Htrz)2(trz)]BF4. En concreto se sintetizaron 3 nuevos tipos de nanoparticulas basadas en el polimero [Fe(Htrz)1-x(NH2trz)x](ClO4)2, siendo x = 0.05, 0.15 y 0.3, en cada caso. Estas nanoparticulas siguen presentando una estrecha distribucion de tamanos y una transicion de espin muy abrupta y con un ancho ciclo de histeresis. Ademas, se observa que este ciclo se desplaza a temperaturas mas proximas a la temperatura ambiente a medida que se aumenta el porcentaje de 4-amino-1, 2, 4- triazol en la muestra. Pero al mismo tiempo se produce una disminucion de la anchura de este ciclo. Por ultimo, en este capitulo se presenta la

  4. Miradas Caleidoscópicas sobre el Chagas. Una experiencia educativa en el Museo de La Plata

    Directory of Open Access Journals (Sweden)

    Mariana Sanmartino

    2012-01-01

    Full Text Available Presentamos resultados y reflexiones en torno a la experiencia "Semana del Chagas en el Museo de La Plata" (La Plata, Provincia de Buenos Aires, Argentina realizada en mayo de 2011. La propuesta tuvo como objetivo la difusión y sensibilización acerca de la problemática del Chagas desde una mirada integral. Las actividades incluyeron una muestra de obras plásticas; la proyección de materiales audiovisuales innovadores; talleres con estudiantes de escuelas primarias y secundarias de la zona; charlas abiertas a cargo de especialistas; la presentación y distribución de materiales didácticos a docentes de escuelas; así como el desarrollo de actividades destinadas al público general. La evaluación de la experiencia es altamente satisfactoria, y de la reflexión sobre lo transitado -durante la organización y en la implementación- surgen múltiples aprendizajes tanto para participantes como para organizadores, de lo cual se desprende el interés por compartir la propuesta y la posibilidad de adecuarla a otros contextos.

  5. La introducción de las telecomunicaciones eléctricas en el Río de la Plata

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    Ariel Sar

    2013-03-01

    Full Text Available Las telecomunicaciones eléctricas fueron introducidas en las repúblicas del Río de la Plata entre 1864 y 1866. Primero Paraguay instaló el ferrocarril, la telegrafía eléctrica y una fundición de acero para fabricar armas y tecnología pesada. A los pocos meses, capitales británicos instalaron una red telegráfica eléctrica entre la Argentina y Uruguay, en el marco de una estrategia de desarrollo económico y de dominación imperial para establecer redes de expansión global conformadas por los telégrafos, los puertos y los ferrocarriles. Estos eventos tecnológicos se produjeron en el marco de un conflicto creciente entre facciones de Argentina, Brasil y Uruguay que desembocaron en la Guerra de la Triple Alianza contra Paraguay, conflagraciones de las que participaron, de una u otra manera, Gran Bretaña y Francia. Las guerras de soberanía rioplatense y la competencia entre potencias europeas impulsa, pues, una revolución tecnológica en el Plata en el campo de las comunicaciones.

  6. La industria del Gran La Plata según el último Censo Nacional Económico

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    Diego Arturi

    2012-12-01

    Full Text Available El artículo tiene como objetivo caracterizar el sector industrial del Gran La Plata en base a información del último Censo Nacional Económico (CNE 2004/2005. En una primer parte se identifican las principales características del sector industrial a escala nacional en los períodos neoliberal y posconvertibilidad, a partir de bibliografía especializada y análisis de series estadísticas e informes técnicos. En una segunda parte se analiza el sector industrial del Gran La Plata en base a entrevistas a informantes calificados y a los datos censales según cantidad de establecimientos, puestos de trabajo ocupados, rama de actividad, tamaño de los locales industriales, productividad y especialización industrial de los municipios; asimismo se realiza una aproximación a niveles de intensidad tecnológica por rama. A partir de este análisis se pueden destacar las siguientes conclusiones: predominio de las micro y pequeñas empresas, productividad superior al promedio nacional, escaso aporte de las ramas de alta intensidad tecnológica y ausencia de especialización que impide definir un perfil industrial marcado.

  7. Mar del Plata (Argentina: la ciudad balnearia de los porteños en el Atlántico suroccidental

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    Yvanne Bouvet

    2005-01-01

    Full Text Available Nacida a fines del siglo 19, Mar del Plata ha devenido —en el término de un siglo— en balneario por excelencia de Buenos Aires y de la Argentina en general. La cultura estival de la playa la ha hecho evolucionar desde un turismo elitista hacia un turismo de masas, impulsando el desarrollo de espacios y estructuras destinadas a alojamiento y ocio para cerca de 3 millones de personas cada año. Con un espacio urbano fuertemente segregativo y en expansión, el litoral está sometido a una fuerte presión antrópica, a una erosión contínua y a una degradación en la calidad de sus aguas. La crisis social, económica y política que atraviesa Argentina crea condiciones poco favorables para la actividad turística y ensombrece el futuro de Mar del Plata.

  8. Bronces y plata tartéssicos de Alhonoz y su hinterland

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    Luis Alberto LÓPEZ PALOMO

    2009-12-01

    Full Text Available RESUMEN: En este artículo se ofrece una síntesis de los objetos metálicos obtenidos en las excavaciones del yacimiento sevillano de Alhonoz a lo largo de las campañas de 1973-75, 1977 y 1978 y se hace mención de otros hallazgos localizados casualmente a orillas del río Genil, entre el yacimiento de Alhonoz y el de Los Castellares (término de Puente Genil, provincia de Córdoba. Las piezas halladas en Alhonoz son: un thymaterion de bronce, no completo, de tipo chipriota, idéntico al que el profesor Karageorghis da a conocer procedente de Angolemi, dentro del tipo B-2 de la sistematización de Almagro Gorbea, que lo fecha hacia el siglo VII-VI a. C , una pequeña figurilla de la diosa Minerva y otros pequeños objetos también broncíneos, de las mismas excavaciones. Se publica también en este artículo un exvoto de plata, muy interesante, que ha sido calificado como «los ojos de Astarté» y que tiene muchas resonancias en el mundo fenicio. Por último se publican otros objetos de bronce procedentes de diferentes lugares cercanos a Alhonoz, y del mismo ambiente arqueológico.ABSTRACT: In this article a synthesis is offered of the metalics objets obtained at the excavations of the Sevillian deposit of Alhonoz during the 1973-75, 1977 and 1978 campaings. And another discovery is mentioned, casually found by the Genii riverside, between the deposits of Alhonoz and Los Castellares (municipal district of Puente Genii, Córdoba province. The pieces discovered at Alhonoz are: an incomplete bronze thymaterion of a Cypriot type, identical to the one made known by profesor Karageorghis, coming from the type B-2 of Almagro Gorbea systematization, which he dates at about the seventh-sixth centuries B.C., a little figure of Minerva goddess, and some other objecrs, also bronzed, from the same excavations. It is also published, in this article, a very interesting silver Ex-voro which has been qualified. Lastly, other bronze objets are published from

  9. Experimental use of Land Surface Models in the La Plata Basin

    Science.gov (United States)

    Goncalves, L.; de Mattos, J. Z.; Sapucci, L. F.; Herdies, D. L.; Berbery, E. H.

    2009-12-01

    Soil moisture is a key variable that controls the partitioning between sensible and latent heat flux, and under favorable conditions, it can modulate precipitation. The overlying boundary layer can be affected by soil moisture anomalies when persisting for an enough period of time. Several studies have shown the influence of surface processes in the South American atmospheric circulation and precipitation patterns. However the absence of a comprehensive observation network over that region represents a disadvantage for determining and quantifying memory and coupling between the land surface and the atmosphere. The La Plata Basin (LPB) in southeastern South America is recognized as an area of great importance for the economic and social development of several countries. Vast areas of this basin have experienced changes in land cover conditions due to the expansion of the agriculture (replacing natural vegetation), but also due to changes in crop types. This work presents results from an ensemble of four land surface models (Noah, CLM, MOSAIC and SiB2) used for climatic characterization of the past 30 years of soil moisture and temperature over the LPB. The Modern Era Retrospective-Analysis for Research and Applications (MERRA), from NASA’s Global Modeling and Assimilation Office (GMAO) was downscaled to be used to force the land surface models at 10Km, 3-hourly resolutions. Two sets of runs were made for this study: first, the LSMs were forced using reanalysis data to characterize the climatological states at coarse resolution, and second, the models were run using South American LDAS forcing fields from 2000 until present at higher resolution. The resulting spread among the different models was used as a measure of uncertainty in the initial states. In particular, the surface states derived from the Noah model were rescaled and used as initial conditions for atmospheric model simulations using the coupled ETA/Noah models. The control run was performed using

  10. Distribución espacial de las parasitosis intestinales en la ciudad de La Plata, Argentina

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    María I Gamboa

    2014-10-01

    Full Text Available El análisis de las parasitosis a diferentes escalas (regional, local se facilita por el Geographic Information System (GIS, que permite identificar áreas con distinto grado de vulnerabilidad. El objetivo del trabajo fue analizar la distribución espacial de las parasitosis intestinales en el partido de La Plata, estableciendo su relación con las condiciones socio-ambientales para identificar áreas con diferente riesgo epidemiológico. Se completó una encuesta epidemiológica y se tomaron muestras seriadas de materia fecal, analizadas por la técnica de Ritchie. Se calcularon niveles de precariedad y vulnerabilidad (Iv, y se compararon con los resultados parasitológicos. Se analizaron parasitológica y ambientalmente 653 personas, de las cuales 585 (89.6% eran niños y 68 (10.4% adultos. El análisis indicó que los más vulnerables (Iv = 3-4 estaban en el sector con menor acceso a servicios de infraestructura urbana. El índice se encontró fuertemente asociado a la prevalencia total de parasitosis intestinales y a las 4 especies patógenas asociadas a la contaminación fecal del ambiente: Trichuris trichiura, Ascaris lumbricoides, Hymenolepis nana y Giardia lamblia (p < 0.01. Enterobius vermicularis, parásito no vinculado a la condición sanitaria de sus hospedadores, no se asoció al Iv. Hubo asociación estadística entre precariedad y parasitosis y se halló que a mayor Iv mayor frecuencia de parasitosis (p < 0.01. El uso de GIS permitió zonificar las variables socioambientales en un gradiente creciente de condiciones desfavorables y su relación con la presencia de especies patógenas. La continuidad de estos estudios en diferentes regiones de Argentina contribuye a la determinación de áreas en riesgo sanitario.

  11. Material tipo de la Colección de Herpetología del Museo de La Plata, Buenos Aires, Argentina

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    Ferraro, Daiana Paola

    2005-12-01

    Full Text Available El Museo de la Plata (Buenos Aires, República Argentina se fundó en 1889, y la colección herpetológica comenzó a funcionar poco tiempo después, bajo la responsabilidad deJulio G. Koslowsky. En esta contribución se listan los ejemplares tipo de Anfibios y Reptiles depositados en la colección herpetológica del Museo de La Plata. El material tipo depositado corresponde a 32 especies descriptas desde 1895 hasta la actualidad, incluyendo: 14 holotipos, 115 paratipos, 4 lectotipos, 22 paralectotipos, 1 neotipo y 12 sintipos (sin incluir los ejemplares extraviados. Se proporciona, para cada taxón, la información completa referida a estatus de cada ejemplar tipo, sexo, datos de recolección y modificaciones taxonómicas posteriores. The La Plata Museum (Buenos Aires, República Argentina was founded on 1889, and after a little time, the herpetological collection started under the responsibility of Julio G. Koslowsky. In this paper the type specimens of Amphibia and Reptilia housed in the collection of the Herpetology Section at the La Plata Museum are listed. These type materials correspondto 32 species described since 1895 until nowadays, and include: 14 holotypes, 115 paratypes, 4 lectotypes, 22 paralectotypes, 1 neotype and 12 sintypes (this list does not include lost specimens. Complete data about taxonomic status, sex, collection data, and subsequent taxonomic changes are given for each taxon.

  12. Phylogeography of the Neotropical catfish Pimelodus albicans (Siluriformes: Pimelodidae from río de la Plata basin, South America, and conservation remarks

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    Julia Vergara

    Full Text Available Pimelodus albicans Valenciennes, 1840 (common name "moncholo" or "bagre blanco" is an endemic species of the family Pimelodidae in the río de la Plata basin. Phylogenetic approach based on cytochrome b sequences was performed to test the existence of a unique evolutionary lineage in P. albicans and to discriminate populations units or subpopulations related to a migration behavior of this taxon in the río de la Plata basin. This study included 34 samples of P. albicans of different collecting sites in the río de la Plata estuary and in the río Arrecifes belonging to the río Paraná basin. Among 614 base pairs in the cytochrome b sequence data set, 203 were variable and 120 were phylogenetically informative sites in P. albicans. A total of twenty haplotypes, nucleotide diversity (p = 0.032 and haplotype diversity = 0.941 were found. Tajima's test showed significant value D= -1.88 (p<0.05 rejecting the neutral mutation hypothesis for the P. albicans data set. All phylogenetic approaches showed that P. albicans included four monophyletic assemblages that were supported by high bootstrap and Bayesian posterior probability values. Minimum spanning network corroborated these groups for P. albicans haplotypes. High genetic structure was found in P. albicans by means of AMOVA analysis showing that the río Arrecifes samples constitute an isolated lineage. Moreover, the high value of genetic divergence (10% between the río de la Plata and the río Arrecifes populations could suggest that P. albicans may be conformed by a sibling species complex. On the other hand, a degree of genetic structuring was detected among different sites of the río de la Plata. A partial isolation of the 760 site may suggest that P. albicans could migrates to different tributaries for reproduction, generating different schools of haplotypes which could mix in the río de la Plata estuary. The high nucleotide diversity found in the 765 site and the existence of gene flow

  13. Los ejemplares tipo de Cicadellinae y Gyponinae (Hemiptera: Auchenorrhyncha: Cicadellidae depositados en el Museo de La Plata, Argentina The type specimens of Cicadellinae and Gyponinae (Hemiptera: Auchenorrhyncha: Cicadellidae housed at the Museo de La Plata, Argentina

    Directory of Open Access Journals (Sweden)

    Susana L. Paradell

    2010-06-01

    Full Text Available En la presente contribución, se realizó un relevamiento de los ejemplares tipo de Cicadellidae, depositados en la colección de la División Entomología del Museo de La Plata (MLP. Fueron examinados y listados 86 ejemplares tipo pertenecientes a 32 especies: siete Cicadellinae y 25 Gyponinae, las que fueron descriptas por los siguientes autores: Berg, DeLong, DeLong & Freytag, DeLong & Martinson, Tesón, Spångberg y Young. Para cada ejemplar tipo se brinda información acerca del nombre específico, referencia bibliográfica, categoría de tipo y procedencia.

  14. Procedimiento de los investigadores de la Universidad Nacional de La Plata en la búsqueda de información = National University of La Plata researchers procedures in information search

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    Silvia Albornoz

    2002-12-01

    Full Text Available La búsqueda de información y sus problemas colaterales inciden en el desarrollo de la actividad de los investigadores. Nos proponemos analizar esta temática a través del estudio de las pautas de comportamiento de investigadores de la Facultad de Humanidades y Ciencias de la Educación de la Universidad de La Plata, para identificar conductas informativas y al mismo tiempo detectar obstáculos que impiden el aprovechamiento óptimo de la Biblioteca Central y las Bibliotecas Departamentales de la Institución. Los resultados obtenidos servirán de base para definir indicadores de calidad aplicables a la mejora continua de los servicios de biblioteca. Como resultado del análisis de metodologías aplicadas en estudios de usuarios se determinó combinar las perspectivas cuantitativa y cualitativa en este trabajo en curso = The search of information and its collateral problems affect the development of the researchers activity. We would like to analyze this subject through the study of the behavior guidelines of researchers of the Faculty of Humanities and Education Sciences of the University of La Plata, in order to identify informative behavior and, at the same time, to find out the obstacles that avoid the optimal use of the Central Library and the Departmental Libraries of the Institution. The obtained results will serve as a base to define quality indicators applicable to the continuous improvement of the library services. As a result of the analysis of methodologies applied to user studies, it was decided to combine the quantitative and qualitative perspectives in this work.

  15. Procedimiento de los investigadores de la Universidad Nacional de La Plata en la búsqueda de información National University of La Plata researchers procedures in information search

    Directory of Open Access Journals (Sweden)

    Silvia Albornoz

    2002-12-01

    Full Text Available La búsqueda de información y sus problemas colaterales inciden en el desarrollo de la actividad de los investigadores. Nos proponemos analizar esta temática a través del estudio de las pautas de comportamiento de investigadores de la Facultad de Humanidades y Ciencias de la Educación de la Universidad de La Plata, para identificar conductas informativas y al mismo tiempo detectar obstáculos que impiden el aprovechamiento óptimo de la Biblioteca Central y las Bibliotecas Departamentales de la Institución. Los resultados obtenidos servirán de base para definir indicadores de calidad aplicables a la mejora continua de los servicios de biblioteca. Como resultado del análisis de metodologías aplicadas en estudios de usuarios se determinó combinar las perspectivas cuantitativa y cualitativa en este trabajo en curso.The search of information and its collateral problems affect the development of the researchers activity. We would like to analyze this subject through the study of the behavior guidelines of researchers of the Faculty of Humanities and Education Sciences of the University of La Plata, in order to identify informative behavior and, at the same time, to find out the obstacles that avoid the optimal use of the Central Library and the Departmental Libraries of the Institution. The obtained results will serve as a base to define quality indicators applicable to the continuous improvement of the library services. As a result of the analysis of methodologies applied to user studies, it was decided to combine the quantitative and qualitative perspectives in this work.

  16. Historical economic and environmental policies influencing trace metal inputs in Montevideo Bay, Río de la Plata.

    Science.gov (United States)

    Bueno, C; Brugnoli, E; Figueira, R C L; Muniz, P; Ferreira, P A L; García Rodríguez, F

    2016-12-15

    Montevideo Bay is located in the middle zone of the Rio de la Plata, and since the foundation of the city, several key economic and environmental policies affected the industry, and thus, metal inputs into this ecosystem. The aim of this study is to evaluate the sedimentary geochemical record of Montevideo Bay, in order to determine the historical inputs of anthropogenic metals to the system. In addition, environmental and economic policies of the country were taken into account to infer the relationship between them and the historic metal input. Concentrations of aluminum, chromium, copper, lead, scandium and zinc were analyzed and the EF and SPI indices were calculated. The analysis showed that since Montevideo foundation, metal concentrations increased in accordance with industry development, and the indices as well as the metal concentration represent a reliable footprint of the history of different economic and environmental policies influencing historical industrial activities. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Los ejemplares tipo de Cicadellinae y Gyponinae (Hemiptera: Auchenorrhyncha: Cicadellidae depositados en el Museo de La Plata, Argentina

    Directory of Open Access Journals (Sweden)

    Susana L. PARADELL

    2010-01-01

    Full Text Available En la presente contribución, se realizó un relevamiento de los ejemplares tipo de Cicadellidae, depositados en la colección de la División Entomología del Museo de La Plata (MLP. Fueron examinados y listados 86 ejemplares tipo pertenecientes a 32 especies: siete Cicadellinae y 25 Gyponinae, las que fueron descriptas por los siguientes autores: Berg, DeLong, DeLong & Freytag, DeLong & Martinson, Spångberg , Tesón y Young. Para cada ejemplar tipo se brinda información acerca del nombre específico, referencia bibliográfica, categoría de tipo y procedencia.

  18. Study of sediment behaviour in Rio de la Plata, Punta Carmelo area with use of radioactive trace

    International Nuclear Information System (INIS)

    Vianna Bandeira, J.; Godinho Pinto, G.; Suarez Antola, R.

    1998-01-01

    This work is related to the sedimentological studies with the application of radioactive tracers, carried out in the region of Puerto Carmelo, Rio de la Plata-Uruguay, under the Tc Project of the International Atomic Energy Agency (IAEA) URU/8/009, with the objective of evaluating the bed load transport of sand, in the region where a new access channel to the harbour of Carmelo, was designed. These studies, performed together hydraulic measurements, were important for the comprehension of the behaviour of the sediment transportation under the action of the hydrodynamic agents (currents and waves); the determination of the bed load rate and its application to the evaluation of the maintenance dredging, the definition of the optimum path for the access channel, based on the deposition process of the injected tracer, 30 cm above the bottom. The maximum accretion rate is for the designed channel is around 11000 m3/year. (author)

  19. Aborto, abandono, y la muerte de Augusta García Platas en Ayacucho, Perú, 1946

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    Raúl Necochea López

    Full Text Available Resumen Augusta García Platas murió tras un aborto clandestino en Ayacucho en 1946. Este ensayo, basado en materiales del Archivo Histórico de Ayacucho, da cuenta del proceso criminal que se abrió para determinar los responsables de su muerte. A pesar de que sindicaron a ciertos individuos como culpables directos de provocar el aborto, las autoridades judiciales consideraban que la causa de fondo de la muerte de la joven había sido el abandono por parte de quienes debían velar por su salud física y moral. Este caso nos brinda la oportunidad de esclarecer las estrategias que los implicados usaban para defenderse de acusaciones criminales. Además, nos ayuda a entender las diversas deficiencias del Poder Judicial peruano de mediados del siglo XX.

  20. The Asamblea del Año XIII in the Rio de la Plata: Eternal Laurels to End the Revolution

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    Esteban Buch

    2016-09-01

    Full Text Available The Asamblea del año XIII, the 1813 Constitutional Assembly in the Río de la Plata, represents at its best revolutionary velocity, with its allegro rhythm towards wider liberties and a more perfect equality, towards an independence of the nation that, without being officially declared, inspires many of its gestures, like the creation of Argentina’s national anthem. A contemporary observer fond of anachronisms might find in it a confirmation that movement is an essential element of democracy. Yet, this dynamic perception should be balanced by reminding that the Assembly’s main project is not to accelerate the revolution, but to terminate it. “Close the period of the revolution, open the epoch of peace and freedom”, says its inaugural declaration. This paper focuses on the tension between these two conceptions of historical temporality.

  1. Compte rendu de la 18e Conférence Internationale sur le Tournesol : Mar del Plata & Balcarce (Argentine, 2012

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    Pilorgé Étienne

    2012-11-01

    Full Text Available The 18th International Sunflower Conference took place in Mar del Plata, Argentina, in February, 2012. The key-points and evolutions of sunflower research were presented, in the fields of agronomy, physiology, genetics and genomics, crop protection, quality and markets. Major evolutions can be observed concerning the sequencing of sunflower genome, announced to be complete by the end of 2012, but also concerning the use of models and the progress in the studies on the interactions between varieties genetic pattern, environment and crop management practices. In crop protection aspects, the evolutions of the major pathogens, downy mildew and Orobanche cumana, have been discussed, as well as the breeding efforts for genetic resistances, or the advances concerning the herbicides tolerant varieties. Evolutions in oil quality aspects have been exposed too, such as varieties enriched in stearic acid, or tocopherols, or with low contents in saturated fatty acids.

  2. As exposições e seus publicos : a paleontologia no Museo de La Plata (Provincia de Buenos Aires, Argentina)

    OpenAIRE

    Sandra Elena Murriello

    2006-01-01

    Resumo: Esta tese pretende ser uma contribução à compreensão do diálogo estabelecido nas instituições museais com seus múltiplos visitantes, o que vem permitindo a sobrevivência, quando não a transformação, e consolidação dos museus como espaços culturais valorizados socialmente. Em particular, analiso a relação estabelecida entre o público do Museo de La Plata (Província de Buenos Aires, Argentina) e suas exposições paleontológicas. Essas exposições e suas valiosas coleções são as mais procu...

  3. The job market and temporary work programs. ANalysis of the case of the Greater La Plata conglomerate 2003-2008

    Directory of Open Access Journals (Sweden)

    Juliana Santa María

    2009-01-01

    Full Text Available This paper aims at looking into the job market situation in the Greater La Plata conglomerate, focusing its attention on the implementation of Temporary Work Programs as a clearly passive tool used by the State -especially during the last few decades- to deal with the population's employment issues. Based on the situation that the region presents, the specific situation of the municipality of Berisso which is part of the conglomerate will be looked into, in order to carry out an in-depth analysis of these types of policies' effective implementation forms and strategies on the municipal level. The Permanent Home Survey (EHP - INDEC, information provided by the Municipality and documents on Employment Policies and Programs will be used in order to complete this work.

  4. The vanguards and the passion for the real Anglo-Saxon Modernism in the Río de la Plata

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    Carina González

    2017-03-01

    Full Text Available The well-known returning of the real marked the beginning of a new revision that emphasizes the crisis of representation and the question of realism as a genre opened to an uncommon leaking. This returning must be rethinking by the reflection about how the avant-garde promotes the debate on aesthetics and politics. This essay proposes an approach to this topic by analyzing modernism as the avant-garde that introduces a third position in the dialectics of high art and popular culture, art and life or the individual and the world. The study of the work of Joyce and Kafka will be addressing by the traditional readings and its approaches from reviews and translations written by main authors in the Río de la Plata´s region.

  5. Otras voces de la Edad de Plata: Francisco Valdés, escritor y crítico literario

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    Guadalupe Nieto Caballero

    2017-02-01

    Full Text Available El artículo estudia la prosa ensayística y aforística de Francisco Valdés, autor extremeño protagonista de la Edad de Plata. En sus textos, Valdés desarrolla una crítica que parte de la perspectiva de un lector atento, llegando a proponer, incluso, reinterpretaciones de las obras que glosa. De sus artículos en prensa se analizan su estilo y los autores que comenta, fuente indiscutible para conocer sus referentes y los caminos de su prosa. Se analizarán también algunos aspectos de su producción aforística a partir de un cuaderno inédito que enlaza perfectamente con la línea de la literatura de la época. 

  6. Labor conflict, general strikes and dynamics of trade union organizations in the Gran La Plata 1969-1972

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    Agustín Nava

    2017-07-01

    Full Text Available This paper is inscribed within studies on the history of the labor movement during the years '60 and '70 in Argentina and aims to analyze the cycle of general strikes and labor conflictivity that took place more specifically between the years 1969-1972 on a particular region: the Gran La Plata. Through a qualitative and quantitative analysis we will approach the dynamics of general strikes and their impact on our study region, as a kind of struggle that allows us to analyze the different tendencies and forms assumed by the conflict, the degrees of unity within the labor movement, the dynamics of trade unions, alliances with other social forces and the relationship with the state. Therefore, this article contributes to study not only certain specific dynamics of labor conflictivity in our study region, but also the more general cycle of social protest and political radicalization that took place in Argentina during the sixties and seventies

  7. México en la Conferencia Económica Mundial de Londres: el Acuerdo de la Plata de 1933

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    Fabián Herrera León

    2010-12-01

    Full Text Available Pese a que a finales del mes de julio de 1933 la Conferencia Económica de Londres fue prácticamente clausurada al entrar en receso, México y otros países productores o usuarios de plata llegaron allí mismo a un acuerdo que ayudaría a equilibrar el mercado de la plata y elevar su precio. Sobre esta base, la política estadunidense de rescate del metal blanco estimulada poco tiempo después, aceleró la recuperación. Como ya ha sido destacado por la historiografía económica, los beneficios que obtuvo México del Acuerdo de Londres y del programa platista estadunidense contribuyeron sustancialmente a la expansión de su sistema monetario y al fortalecimiento de su banco central en el marco de la crisis. Sin embargo, se ha pasado por alto la cuidadosa e interesante actividad preparatoria del país para pugnar por este tipo de medidas, omisión que ha sido la principal motivación del autor en la realización de este artículo.Although the London Economic Conference (1933 was called off sine die at the end of July, Mexico and other silver producing and consuming countries came to an agreement that made possible to stabilize and increase the rate of this precious metal. As economic historiography has already emphasized, the benefits obtained by Mexico with the London Silver Agreement in 1933 favored both monetary system expansion and Central Bank strengthening during the crisis. Yet, the remarkable and cautious preparatory activity that Mexico fulfills to reach that goal has been neglected. This lack of information has prevented us to entirely understand this economic phenomenon and has been the author's main motivation while doing this paper.

  8. On the use of MODIS and TRMM products to simulate hydrological processes in the La Plata Basin

    Science.gov (United States)

    Saavedra Valeriano, O. C.; Koike, T.; Berbery, E. H.

    2009-12-01

    La Plata basin is targeted to establish a distributed water-energy balance model using NASA and JAXA satellite products to estimate fluxes like the river discharge at sub-basin scales. The coupled model is called the Water and Energy Budget-based Distributed Hydrological Model (WEB-DHM), already tested with success in the Little Washita basin, Oklahoma, and the upper Tone River in Japan. The model demonstrated the ability to reproduce point-scale energy fluxes, CO2 flux, and river discharges. Moreover, the model showed the ability to predict the basin-scale surface soil moisture evolution in a spatially distributed fashion. In the context of the La Plata Basin, the first step was to set-up the water balance component of the distributed hydrological model of the entire basin using available global geographical data sets. The geomorphology of the basin was extracted using 1-km DEM resolution (obtained from EROS, Hydro 1K). The total delineated watershed reached 3.246 millions km2, identifying 145 sub-basins with a computing grid of 10-km. The distribution of land cover, land surface temperature, LAI and FPAR were obtained from MODIS products. In a first instance, the model was forced by gridded rainfall from the Climate Prediction Center (derived from available rain gauges) and satellite precipitation from TRMM 3B42 (NASA & JAXA). The simulated river discharge using both sources of data was compared and the overall low flow and normal peaks were identified. It was found that the extreme peaks tend to be overestimated when using TRMM 3B42. However, TRMM data allows tracking rainfall patterns which might be missed by the sparse distribution of rain gauges over some areas of the basin.

  9. Oil spill in the Rio de la Plata estuary, Argentina: 1. Biogeochemical assessment of waters, sediments, soils and biota

    International Nuclear Information System (INIS)

    Colombo, J.C.; Barreda, A.; Bilos, C.; Cappelletti, N.; Demichelis, S.; Lombardi, P.; Migoya, M.C.; Skorupka, C.; Suarez, G.

    2005-01-01

    Aliphatic (ALI) and aromatic (ARO) hydrocarbon concentrations, composition and sources were evaluated in waters, sediments, soils and biota to assess the impact of ∼1000 tons of oil spilled in Rio de la Plata coastal waters. Total ALI levels ranged from 0.4-262 μg/l in waters, 0.01-87 μg/g in sediments, 5-39 μg/g in bivalves, 12-323 μg/g in macrophytes to 948-5187 μg/g in soils. ARO varied from non-detected 10 μg/l, 0.01-1.3 μg/g, 1.0-16 μg/g, 0.5-6.9 μg/g to 22-67 μg/g, respectively. Offshore (1, 5, 15 km) waters and sediments were little affected and contained low background hydrocarbon levels reflecting an effective wind-driven transport of the slick to the coast. Six months after the spill, coastal waters, sediments, soils and biota still presented very high levels exceeding baseline concentrations by 1-3 orders of magnitude. UCM/resolved aliphatic ratio showed a clear trend of increasing decay: coastal waters (3.3) n-C23) and petrogenic/pyrogenic relationship (methylated/unsubstitued PAH) discriminated the samples according to the different degree of impact. The following paper present the results of the study of the progress of hydrocarbon disappearance in sediments and soils 13 and 42 months after the spill. - The Oil spill impact the Rio de la Plata was evaluated by HRGC and multivariate techniques applied to waters, sediments and biota

  10. REDESCRIPCIÓN DE POTAMOLITHUS SUPERSULCATUS PILSBRY, 1896 (GASTROPODA, TATEIDAE DEL SUR DE LA CUENCA DEL PLATA

    Directory of Open Access Journals (Sweden)

    MICAELA DE LUCÍA

    Full Text Available RESUMEN El género Potamolithus Pilsbry, 1896 (Gastropoda; Tateidae, posee 31 especies, 22 de las cuales se hayan en la Argentina distribuidas principalmente en la cuenca Del Plata, definiendo al río Uruguay y al Río de la Plata como una zona caliente de diversidad en gasterópodos dulceacuícolas. Sin embargo, la mayoría de sus especies han sido descriptas solo por caracteres conquilógicos y, unas pocas tienen datos anatómicos, conllevando a la descripción de subespecies o morfos que se superponen unos a otros. A Potamolithus lapidum algunos autores le atribuyen cuatro subespecies (con datos conquiológicos, y una con datos parciales de anatomía blanda, sin embargo otros incluyen ocho “morfos”. Aquí nosotros damos un comienzo en el estudio de Potamolithus lapidum elevando a Potamolithus lapidum supersulcatus Pilsbry, 1896 a la categoría de especie, de la cual solo se conocen caracteres conquiológicos y radulares parcialmente. Aportamos datos de: concha, órganos paleales, cabeza, pie, pene, rádula, sistemas reproductor femenino y masculino, sistema nervioso y, secuencia parcial del gen mitocondrial citocromo c oxidasa subunidad I. Es necesario realizar una buena descripción de las especies del género Potamolithus debido a que algunas de las especies ya han sido citadas como especies vulnerables y que habitan ríos que están siendo modificados por la actividad humana y por la presencia del bivalvo invasor Limnoperna fortunei.

  11. La ciudad y la corte como espacios de poder en Hispanoamérica. La plata colonial

    Directory of Open Access Journals (Sweden)

    Bridikhina, Eugenia

    2007-08-01

    Full Text Available This article demostrates how the City of La Plata, headquarters of the Audiencia and the Archbishopric, became defined as the Provincial Court, the centre of courtesan life, and the ceremonial centre of the monarchy. Public ceremonies and etiquette served as an instrument for royal domination represented in the social hierarchy, which defined and limited the social mobility of protagonists in colonial society. Ruling class acceptance of norms of conduct identical to Royal Court, and a similar social hierarchy with similar norms allowed for the functioning of the competitive and antagonistic worlds of Charca´s society.

    Este artículo pretende demostrar que la ciudad de La Plata, sede de la Audiencia y Arzobispado se definió como la Corte provincial, el centro de vida cortesana y el escenario ceremonial de la monarquía. Las ceremonias públicas y etiquetas que se realizaban en este espacio del poder servían como un instrumento de dominio real, representaban y reforzaban la jerarquía social, marcando el lugar que sus protagonistas tenían en sociedad colonial. La aceptación por las clases dirigentes de pautas de conducta y sociabilidad idénticas a los de la Corte Real, y de un modelo similar de diferenciación jerárquica, con sus normas y reglas hacía que funcionara el mundo competitivo y antagónico de la sociedad charqueña.

  12. Natural and human forcing in recent geomorphic change; case studies in the Rio de la Plata basin.

    Science.gov (United States)

    Bonachea, Jaime; Bruschi, Viola M; Hurtado, Martín A; Forte, Luis M; da Silva, Mario; Etcheverry, Ricardo; Cavallotto, José L; Dantas, Marcilene F; Pejon, Osni J; Zuquette, Lázaro V; Bezerra, Maria Angélica de O; Remondo, Juan; Rivas, Victoria; Gómez-Arozamena, José; Fernández, Gema; Cendrero, Antonio

    2010-06-01

    An analysis of geomorphic system's response to change in human and natural drivers in some areas within the Río de la Plata basin is presented. The aim is to determine whether an acceleration of geomorphic processes has taken place in recent years and, if so, to what extent it is due to natural (climate) or human (land-use) drivers. Study areas of different size, socio-economic and geomorphic conditions have been selected: the Río de la Plata estuary and three sub-basins within its watershed. Sediment cores were extracted and dated ((210)Pb) to determine sedimentation rates since the end of the 19th century. Rates were compared with time series on rainfall as well as human drivers such as population, GDP, livestock load, crop area, energy consumption or cement consumption, all of them related to human capacity to disturb land surface. Data on river discharge were also gathered. Results obtained indicate that sedimentation rates during the last century have remained essentially constant in a remote Andean basin, whereas they show important increases in the other two, particularly one located by the São Paulo metropolitan area. Rates in the estuary are somewhere in between. It appears that there is an intensification of denudation/sedimentation processes within the basin. Rainfall remained stable or varied very slightly during the period analysed and does not seem to explain increases of sedimentation rates observed. Human drivers, particularly those more directly related to capacity to disturb land surface (GDP, energy or cement consumption) show variations that suggest human forcing is a more likely explanation for the observed change in geomorphic processes. It appears that a marked increase in denudation, of a "technological" nature, is taking place in this basin and leading to an acceleration of sediment supply. This is coherent with similar increases observed in other regions. Copyright (c) 2010 Elsevier B.V. All rights reserved.

  13. Creating diverse wildlife habitat at La Plata mine, Northwestern New Mexico, a case study: part 2. soils and vegetation

    Energy Technology Data Exchange (ETDEWEB)

    Musslewhite, B.D.; Buchanan, B.A.; Ramsey, T.C.; Hamilton, J.S.; Luther, J. [Buchanan Consultants Ltd., Farmington, NM (United States)

    2001-07-01

    Biodiversity has increasingly become an important issue in determining the success of reclaimed minelands. The post-mine land-use of La Plata Mine is wildlife habitat, primarily for ungulates and small mammals. A reclamation plan was developed to promote biodiversity of reclaimed lands through the use of variable soil substrates, landscape features, and targeted seed mixes. A GIS was used to delineate the post-mine final surface contour into eight slope classes and eight aspect classes. The class information was used to develop four reclamation land types: 1. Upland shrub - north aspects, 2. Upland shrub - south aspects, 3. Grassland, and 4. Drainage. These land types correspond to four reclamation vegetation types. Suitable spoil materials and coarse textured topsoil materials were targeted for use on strongly sloping areas to minimize soil loss. Finer textured topsoil materials were targeted for the grassland and drainage types. The replacement depth of topsoil and topsoil substitute materials was varied for the reclamation vegetation types. Pre-mine vegetation inventories were used to develop unique seed mixes specific to physical habitat conditions exhibited by each land-type. Research conducted at La Plata Mine found that topsoil replacement thickness less than 15 cm promotes shrub establishment and topsoil thickness greater than 30 cm promotes native grass species. Therefore, areas designated for shrub communities will receive an average of 10 cm of topsoil or topsoil substitute material and the areas designated for grassland and drainage type communities will receive a minimum of 40 cm of topsoil. 12 refs., 1 fig., 1 tab.

  14. Variability in warm-season atmospheric circulation and precipitation patterns over subtropical South America: relationships between the South Atlantic convergence zone and large-scale organized convection over the La Plata basin

    Science.gov (United States)

    Mattingly, Kyle S.; Mote, Thomas L.

    2017-01-01

    Warm-season precipitation variability over subtropical South America is characterized by an inverse relationship between the South Atlantic convergence zone (SACZ) and precipitation over the central and western La Plata basin of southeastern South America. This study extends the analysis of this "South American Seesaw" precipitation dipole to relationships between the SACZ and large, long-lived mesoscale convective systems (LLCSs) over the La Plata basin. By classifying SACZ events into distinct continental and oceanic categories and building a logistic regression model that relates LLCS activity across the region to continental and oceanic SACZ precipitation, a detailed account of spatial variability in the out-of-phase coupling between the SACZ and large-scale organized convection over the La Plata basin is provided. Enhanced precipitation in the continental SACZ is found to result in increased LLCS activity over northern, northeastern, and western sections of the La Plata basin, in association with poleward atmospheric moisture flux from the Amazon basin toward these regions, and a decrease in the probability of LLCS occurrence over the southeastern La Plata basin. Increased oceanic SACZ precipitation, however, was strongly related to reduced atmospheric moisture and decreased probability of LLCS occurrence over nearly the entire La Plata basin. These results suggest that continental SACZ activity and large-scale organized convection over the northern and eastern sections of the La Plata basin are closely tied to atmospheric moisture transport from the Amazon basin, while the warm coastal Brazil Current may also play an important role as an evaporative moisture source for LLCSs over the central and western La Plata basin.

  15. De la antigüedad del hombre en el Plata a la distribución de las antigüedades en el mapa: los criterios de organización de las colecciones antropológicas del Museo de La Plata entre 1897 y 1930 From the antiquity of man in Argentina’s Plata region to the distribution of antiquities across the map: the organization of the Museu de La Plata’s anthropological colletion, 1897-1930

    Directory of Open Access Journals (Sweden)

    Irina Podgorny

    1999-06-01

    Full Text Available En este trabajo se analizan los criterios de organización de las colecciones antropológicas del Museo de La Plata vigentes entre 1897 y 1930. Bajo el nombre de ‘antropológicas’ se incluyen las colecciones correspondientes a las exhibiciones de las salas de antropología, etnografía y arqueología. Aunque el criterio que finalmente imperó fue el ordenamiento por regiones geográficas, según el sistema de Enrique Delachaux, se discutirán además las otras posibilidades de ordenamiento (etnológico, lingüístico y cronológico que aunque conocidas por las autoridades y científicos del Museo de La Plata fueron descartadas.The article analyzes the criteria for arranging and classifying anthropological collections (that is, anthropology, ethnography, and archeology exhibit rooms adopted at the Museo de La Plata during 1897-1930. The criterion ultimately selected was arrangement by geographical regions, using a system devised by Enrique Delachaux. The article examines other rules of classification as well, familiar to the museum’s curators and scientists but rejected by them: ethnological, linguistic, and chronological criteria.

  16. Protección ambiental del Río de la Plata y su frente marítimo: el marco jurídico general

    Directory of Open Access Journals (Sweden)

    Heber Arbuet Vignali

    2014-07-01

    Full Text Available Versión escrita de la conferencia dictada en el Simposio sobre aspectos jurídicos de la protección ambiental del Río de la Plata y su Frente Marítimo (Montevideo: 21 nov.2001Contenido: Introducción. Importancia del derecho en las relaciones humanas. Importancia del derecho en el asunto que nos convoca. El polifacético marco jurídico de este proyecto. La aparición de los nuevos sistemas. La nueva realidad socio política que debe ser regulada jurídicamente. Importancia de estas ideas para la protección ambiental en el Plata

  17. Ambientes de sedimentación vinculados al acuífero Puelche en la región de La Plata

    OpenAIRE

    García, Juan Manuel; Kruse, Eduardo; Deluchi, Marta

    2016-01-01

    Se plantea una actualización de las características dimensionales e interpretación del ambiente de sedimentación en función de las características morfológicas de la base y el techo del Acuífero Puelche en el área abarcada por las cuencas hidrográficas que drenan hacia el Río de la Plata en los Partidos de Berisso, Ensenada y La Plata (Provincia de Buenos Aires). La metodología incluyó la recopilación y revisión de perfiles de perforación antiguos y recientes, los cuales permitieron la elabor...

  18. Design, construction and characterization of a rural solar furnace; Diseno, construccion y caracterizacion de un horno solar rural

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez Luna, Gabriela

    2001-06-15

    centigrade, followed of the condition using 6 liters of oil, in which a maximum temperature of 115 centigrade was obtained and in the tests with 6 liters of water as load a maximum temperature of 95 centigrade was registered. In these tests the temperature of the oil surpasses 60 centigrade during an approximate period of 7 hours and is higher than 80 centigrade by a lapse of 5 hours. The water temperature is higher than 60 centigrade for a period of more than 5 hours and during 3 hours is higher than 80 centigrade. These results are satisfactory, because they assure the accomplishment of the process of baking inside the furnace. A calculation program was elaborated to implement the theoretical model of the concentration. This program reads the data of radiation intensity in the horizontal plane supplied by the weather station of the CIE and determines the incident radiation in the furnace collector. The theoretical model of the thermal behavior was implemented in another computer program; this program reads the data of the incident radiation in the collector of the furnace and the data of room temperature and calculates the temperature of the furnace as a time function. The model overestimates the temperature reached in the furnace, nevertheless reproduces qualitatively the thermal behavior of the same. In spite of the limitations of the theoretical model, this can be of utility in achieving the reproduction of the temperature of the load experimentally registered, through an effective coefficient of heat losses and an effective coefficient of heat capacity, characteristic of each one of the conditions of the test. [Spanish] Esta tesis presenta el diseno, construccion y caracterizacion de un horno solar tipo caja para su uso en comunidades rurales en la zona intertropical. El trabajo presentado en esta tesis parte del diseno opto-geometrico de un horno solar tipo caja propuesto por un entusiasta grupo de jovenes estudiantes (Acosta et al., 1996, Vazquez et al., 1998

  19. Síntesis y Caracterización de Ag2Cu2O3, el primer óxido de cobre y plata

    Directory of Open Access Journals (Sweden)

    Gómez-Romero, P.

    2000-06-01

    Full Text Available Despite the crystal-chemical similarities between copper and silver ions, there is no known silver copper oxide, neither natural nor synthetic. In this work, we present the synthesis at room-temperature of the first silver copper oxide of formula Ag2Cu2O3 (tetragonal, a=5.8857(3Å, c=10.6868(7Å, space group I41/amd, Z=4. It should be noted that the thermal stability of this new oxide is enhanced with respect to Ag2O or even CuO. The structure consists of alternating chains of edge-sharing square planar Cu(II and zigzag chains of linearly coordinated Ag(I ions.A pesar de las similitudes cristaloquímicas entre los iones de cobre y los de plata, no existe ningún óxido mixto de cobre y plata ni natural ni sintético. En este trabajo se presenta la síntesis a bajas temperaturas del primer óxido mixto de cobre y plata, de fórmula Ag2Cu2O3 (tetragonal, a=5.8857(3Å, c=10.6868(7Å, grupo espacial I41/amd, Z=4. Este óxido posee una estabilidad térmica superior a los correspondientes óxidos de cobre y de plata. Contiene cadenas de iones Cu(II cuadrado-planos que alternan con cadenas en zig-zag de Ag(I con coordinación lineal.

  20. Mario Bunge en la Universidad Nacional de La Plata : Breve testimonio de su visita en el año 2000

    OpenAIRE

    Bunge, Mario

    2000-01-01

    Radio Universidad Nacional de La Plata registra un breve testimonio del Dr. Mario Bunge en su visita a la UNLP en el año 2000. Resalta su paso por esta Universidad, así como las características de la misma. Mario Augusto Bunge: nació en Buenos Aires el 21 de septiembre de 1919. Físico y filósofo, se graduó en la UNLP en 1952. Reside en Montreal (Canadá).

  1. Contribución a la identificación de esporas del Reino Fungi en la atmósfera de La Plata, Argentina

    OpenAIRE

    Nitiu, Daniela S.; Mallo, Andrea C.; Gardella Sambeth, María C.; Morbelli, Marta A.

    2010-01-01

    Based on the aeromycological analysis of La Plata city, artificial Morphological Groups of fungal spores were defined. This study is a methodological contribution to the identification and counting of a fraction of the atmospheric micobiota. For the definition of groups, the criteria of Saccardo (1886) were taken into account and the groupings created by Díaz et al. (1998) and Aira et al. (2005) have been reformulated. Four new groups have been created and other sporal types have be...

  2. The Containment of Radioactive Wastes in Deep Geologic Formations; L'Elimination des Dechets Radioactifs dans les Formations Geologiques Profondes; 0423 0414 0414 ; Evacuacion de Desechos Radiactivos en Formaciones Geologicas Profundas

    Energy Technology Data Exchange (ETDEWEB)

    Kaufman, W. J. [University of California, Berkeley (United States)

    1960-07-01

    desechos en estado semi-solido que han de almacenarse de modo permanente. Se estima que en tales casos las formaciones geologicas profundas pueden constituir un lugar de evacuacion satisfactorio desde el punto de vista de la seguridad y de la economia. En las formaciones de arenisca resulta posible acumular grandes cantidades de desechos con un alto grado de estabilidad del confinamiento. Merced a sus cavidades intersticiales y caracteristicas de intercambio ionico, esas formaciones suelen poseer una capacidad de almacenamiento muy considerable. En principio, el sistema de evacuacion que utiliza las formaciones geologicas profundas ha de consistir en un conjunto de pozos de inyeccion por los que se introducen los desechos, y de pozos de compensacion que sirven para reducir la presion en la boca de los pozos, medir la radiactividad y dirigir el flujo de tal modo que se aproveche al maximo la capacidad de almacenamiento de la formacion. Entre los datos necesarios para proyectar un sistema de este tipo figuran las propiedades de dispersion de la formacion sus caracteristicas de intercambio ionico y las propiedades quimicas y radioquimicas de los desechos. En el Centro tecnologico experimental de la Universidad de California viene funcionando desde hace dos anos un sistema piloto de dos pozos con una capa acuifera. (author) [Russian] Obychno na predprijatijah himicheskoj obrabatyvajushhej promyshlennosti radioaktivnye othody s nizkim i srednim urovnjami aktivnosti imejut mesto v takom bol'shom kolichestve, chto ih hranenie v techenie dolgogo vremeni nerentabel'no. Vo mnogih sluchajah himicheskaja obrabotka othodov mozhet obespechit' dostatochnuju ih dezaktivizaciju dlja otvoda othodov v reki ili morja. Odnako v nekotoryh sluchajah takie metody trebujut zatrat i libo ne obespechivajut dostatochnoj dezaktivacii, libo privodjat v itoge k obrazovaniju chrezvychajno bol'shogo kolichestva polutverdyh othodov, dlja kotoryh neobhodimo obespechit' stacionarnoe hranenie. Predpolagaetsja

  3. Oil spill in the Rio de la Plata estuary, Argentina: 2-hydrocarbon disappearance rates in sediments and soils

    International Nuclear Information System (INIS)

    Colombo, J.C.; Barreda, A.; Bilos, C.; Cappelletti, N.; Migoya, M.C.; Skorupka, C.

    2005-01-01

    The 6-month assessment of the oil spill impact in the Rio de la Plata described in the preceding paper [Colombo, J.C., Barreda, A., Bilos, C., Cappelletti, N., Demichelis, S., Lombardi, P., Migoya, M.C., Skorupka, C., Suarez, G., 2004. Oil spill in the Rio de la Plata estuary, Argentina: 1 - biogeochemical assessment of waters, sediments, soils and biota. Environmental Pollution] was followed by a 13- and 42-month campaigns to evaluate the progress of hydrocarbon decay. Average sediment hydrocarbon concentrations in each sampling include high variability (85-260%) due to contrasting site conditions, but reflect a significant overall decrease after 3 years of the spill: 17 ± 27, 18 ± 39 to 0.54 ± 1.4 μg g -1 for aliphatics; 0.44 ± 0.49, 0.99 ± 1.6 to 0.04 ± 0.03 μg g -1 for aromatics at 6, 13 and 42 months, respectively. Average soil hydrocarbon levels are 100-1000 times higher and less variable (61-169%) than sediment values, but display a clear attenuation: 3678 ± 2369, 1880 ± 1141 to 6.0 ± 10 μg g -1 for aliphatics and 38 ± 26, 49 ± 32 to 0.06 ± 0.04 μg g -1 for aromatics. Hydrocarbon concentrations modeled to first-order rate equations yield average rate constants of total loss (biotic + abiotic) twice as higher in soils (k = 0.18-0.19 month -1 ) relative to sediments (0.08-0.10 month -1 ). Individual aliphatic rate constants decrease with increasing molecular weight from 0.21 ± 0.07 month -1 for isoprenoids and -1 for >n-C27, similar to hopanes (0.10 ± 0.05 month -1 ). Aromatics disappearance rates were more homogeneous with higher values for methylated relative to unsubstituted species (0.17 ± 0.05 vs. 0.12 ± 0.05 months -1 ). Continued hydrocarbon inputs, either from biogenic (algal n-C15,17; vascular plant n-C27,29) or combustion related sources (fluoranthene and pyrene), appear to contribute to reduced disappearance rate. According to the different loss rates, hydrocarbons showed clear compositional changes from 6-13 to 42 months

  4. Análisis de las causas de muerte de los primeros habitantes de la ciudad de La Plata (1887

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    Flores, Olga B.

    2003-01-01

    Full Text Available El presente trabajo constituye un estudio preliminar que forma parte de un proyecto más amplio acreditado por la Universidad Nacional de La Plata y avalado por la Municipalidad de esa localidad "El Cementerio de La Plata. Su contexto histórico". Nuestra investigación se basó fundamentalmente en el análisis de las actas de defunción del Archivo del Cementerio Municipal con el fin de indagar sobre la incidencia diferencial o no de las causas de muerte en relación con la nacionalidad, el sexo, la edad, la profesión, entre otras. Estos datos fueron volcados en planillas con las que se sistematizó la información para toda la población. A partir de esta población, se determinó una muestra compuesta por todos los individuos de ambos sexos que se encuentran en las sepulturas en tierra y abarca el primer año de funcionamiento del Cementerio Municipal. El objetivo del presente trabajo fue caracterizar cómo se distribuyeron las causas de muerte y su incidencia sobre los grupos de edad, género y grupo social, en los decesos ocurridos durante 1887. Según se desprende de los datos analizados, la probabilidad de fallecer antes de cumplir el año de vida es de más del 60%. Las razones para esta alta mortalidad infantil deberán buscarse en las condiciones sanitarias y nutricionales imperantes en la época y para este grupo social, considerando las enfermedades de mayor incidencia en los subadultos; también deben agregarse algunos casos de fallecimiento en los primeros días de vida por falta de desarrollo. En este grupo de edad las causas de muerte más comunes corresponden a las que pertenecen al sistema digestivo, respiratorio, infecciosas y en adultos a enfermedades cardiovasculares, cerebrales, etc.

  5. EL CONSENTIMIENTO INFORMADO EN ODONTÓLOGOS RESIDENTES DE LA FACULTAD DE ODONTOLOGÍA DE LA UNIVERSIDAD NACIONAL DE LA PLATA O CONSENTIMENTO INFORMADO EM ODONTÓLOGOS RESIDENTES DA FACULDADE DE ODONTOLOGIA DA UNIVERSIDADE NACIONAL DE LA PLATA INFORMED CONSENT IN ODONTOLOGY RESIDENTS AT THE DENTISTRY FACULTY, LA PLATA'S NATIONAL UNIVERSITY

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    Ricardo Miguel

    2006-01-01

    Full Text Available Este trabajo se fundamenta en la necesidad de obtener datos sobre la práctica del consentimiento informado realizado por odontólogos. Los datos pertenecen al Programa de Residencias Odontológicas Universitarias (ROU de la Facultad de Odontología de la Universidad Nacional de La Plata (UNLP. La investigación tiene como intención conocer diferentes aspectos respecto a las fortalezas y debilidades de su utilización actual. A partir de los datos, se puede concluir que, a pesar de que los conocimientos teóricos sobre la práctica del consentimiento informado son escasos, existe una tendencia significativa a destinar tiempo en la consulta dental para su empleo, especialmente en la nueva generación. Se considera imperativo incluir en la malla curricular y en los programas académicos odontológicos principios éticos y legales en relación con el proceso de consentimiento informadoEste trabalho fundamenta a necessidade de se obter dados sobre a prática do consentimento informado realizado por odontólogos. Os dados pertencem ao Programa de Residencias Odontológicas Universitárias (ROU da Faculdade de Odontologia da Universidade Nacional de la Plata (UNLP. A pesquisa tem como objetivo conhecer os diferentes aspectos, a respeito das forças e fraquezas de sua utilzação atual. A partir dos dados, se pode concluir que, apesar de serem escassos os conhecimentos teóricos sobre a prática do consentimento informado, existe uma tendencia significativa a destinar tempo na consulta dental para seu uso, especialmente na nova geração. Considera-se um imperativo incluir no curriculo de formação profissional e nos programas acadêmicos odontológicos, princípios éticos e legais relacionados com o processo do consentimento informadoThis work is based upon the need to obtain data on the practice of informed consent carried out by dentists. Data was generated from the University Residence Program at the Dentistry Faculty, L.P.N.U., Argentina. The

  6. Sewage-induced disturbance on polychaetes inhabiting intertidal mussel beds of Brachidontes rodriguezii off Mar del Plata (SW Atlantic, Argentina.

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    Rodolfo Elías

    2006-12-01

    Full Text Available Continuous and short-term disturbances are produced on intertidal Brachidontes rodriguezii mussel beds by the sewage outfall of Mar del Plata, SW Atlantic. The effects on the associated polychaetes living on and between mussels were investigated, in both the spatial and short-term temporal scales. Multivariate methods show that the polychaete fauna was influenced by tidal level, total amount of sediment accumulated between mussels, distance from the sewage outfall, organic carbon of interstitial sediments, and sewage volume before and after the summer season. Environmental variables in the water column fitted with a spatial and temporal organic gradient. Capitella ‘capitata’ sp. showed typical opportunistic behaviour in relation to organic enrichment, as did Neanthes succinea, both being numerically dominant near the sewage discharge. Cirratulus sp., Caulleriella alata, and Boccardia polybranchia were common at intermediate distances from the outfall. Syllis prolixa, S. gracilis, and Protoariciella uncinata reached their highest abundance at intermediate stations and were characteristic of the control site. Close to the outfall mussel density and dominance is low, and opportunist polychaetes successfully colonize organically enriched interstitial sediments. At intermediate distances from the outfall sediments retained by mussels reach their maximum values, and density of polychaetes is also high. The control station is characterized by monolayered mussel beds and very low diversity of polychaetes. Opportunistic polychaetes increase in response to short-term increases of sewage discharge during the summer season (November-March.

  7. Raman Identification of Pigments in Wall Paintings of the Colonial Period from Bolivian Churches in the Ruta De La Plata

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    Carlos Rúa

    2018-03-01

    Full Text Available Micro-Raman spectroscopy was used to analyze and identify pigments and determine the palette of color in wall paintings from four churches of the Colonial Period, in the Bolivian highlands. The ancient churches Santiago de Callapa, Curahuara de Carangas, NuestraSeñora de Copacabana de Andamarca and San José de Soracachi were constructed during the 17th and 18th centuries, around the important colonial Ruta de la Plata, between Potosí city and Arica harbor on the Pacific coast of South America. Most pigments used in the wall paintings correspond to inorganic minerals as well as to organic colorants. Fully chlorinated copper phthalocyanine (green, copper phthalocyanine (blue, β-naphthol (yellow and benzoimidazolone (red, were identified in the corresponding colored areas suggesting subsequent recent interventions or restorations. Ground layer materials were also characterized. The present results allow for discussion of the pictorial techniques used in the Andean highland during the colonial period and allow conservators and restorers to make important decisions regarding the type of intervention to perform in the case of these important historical and patrimonial monuments.

  8. Occurrence of Toxic Cyanobacterial Blooms in Rio de la Plata Estuary, Argentina: Field Study and Data Analysis

    Science.gov (United States)

    Giannuzzi, L.; Carvajal, G.; Corradini, M. G.; Araujo Andrade, C.; Echenique, R.; Andrinolo, D.

    2012-01-01

    Water samples were collected during 3 years (2004–2007) at three sampling sites in the Rio de la Plata estuary. Thirteen biological, physical, and chemical parameters were determined on the water samples. The presence of microcystin-LR in the reservoir samples, and also in domestic water samples, was confirmed and quantified. Microcystin-LR concentration ranged between 0.02 and 8.6 μg.L−1. Principal components analysis was used to identify the factors promoting cyanobacteria growth. The proliferation of cyanobacteria was accompanied by the presence of high total and fecal coliforms bacteria (>1500 MNP/100 mL), temperature ≥25°C, and total phosphorus content ≥1.24 mg·L−1. The observed fluctuating patterns of Microcystis aeruginosa, total coliforms, and Microcystin-LR were also described by probabilistic models based on the log-normal and extreme value distributions. The sampling sites were compared in terms of the distribution parameters and the probability of observing high concentrations for Microcystis aeruginosa, total coliforms, and microcystin-LR concentration. PMID:22523486

  9. Immigration, science and health: risks control and expanding rights in the Rio de la Plata Basin (1873-1911

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    Fernanda Rebelo-Pinto

    2016-12-01

    Full Text Available This paper analyzes how immigration process in the Rio de Plata Basin countries, specifically Brazil and Argentina, promoted inflexions in the sanitations agreements in the end of 19th century. The port is a device within in which are defined knowledge and standards and are established interventions on people in transit, particularly immigrants. The barriers in the agreements between these countries were not only related to controversies within medical and scientific communities but also to political and economics tensions linked to the labor immigrants disputes. In the beginning of 20th century, we can see a shift of interest and issues related to public health: epidemic control was not enough. The states must guarantee some benefits to the populations, especially heath care. This new view is analyzed according to the understanding and uses of the liberal ideology concerning risk self-regulations, collectivization of welfare and expanding of civil and social rights. This process is leveraged in parts by the inclusion of the immigrants in theses societies.

  10. Arquitectura de sitios Web de bibliotecas universitarias: el sistema de bibliotecas de la Universidad Nacional de La Plata, Argentina

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    María Cecilia Corda

    2013-10-01

    Full Text Available Este trabajo descriptivo exploratorio se propone analizar la arquitectura de información (AI de sitios Web de bibliotecas de la Universidad Nacional de La Plata (UNLP, Argentina. Se analizaron 17 bibliotecas y se aplicó una grilla para recabar 10 aspectos relevantes. Los resultados fueron: 1. Ubicación del sitio Web de la biblioteca: 9 sitios incluidos en la página principal de la facultad. 2. Etiquetado de contenidos: terminología simple, sin jergas; no hay homogeneidad entre las bibliotecas. 3. Capacidad de búsqueda: 62% positiva, 38% negativa. 4. Sistema de búsqueda: simple 43%, compleja 10%, con ayudas 10%, ninguno 38%. 5. Sistemas de navegación: globales 5%, jerárquicos 79%, locales 5%, ninguno 11%. 6. Herramientas de navegación: barras 16%, frames o marcos 30%, índices 2%, mapas de sitio 7%, menús horizontales 9%, menús verticales 35%. 7. Sindicación de contenidos RSS: 3 sitios. 8. Otros servicios: chat 7%, descarga de documentos 16%, envío de formularios 14%, instructivos 21%, links a otras páginas 23%, tutoriales 5%, otros 14%. 9. Accesibilidad Web: 1 sitio. 10. Otras observaciones: ninguna. Se concluye que el desarrollo de los sitios es dispar y se recomienda considerar pautas de AI como parte de la cooperación en la red de bibliotecas de la UNLP.

  11. Proyecto integral de acondicionamiento de cuerpos momificados de la colección del Museo de La Plata

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    Reca, María Marta

    2009-01-01

    Full Text Available Con motivo de la decisión institucional de no exhibir restos humanos de procedencia americana, desde la Unidad de Conservación y Exhibición del Museo de La Plata se inició la delicada tarea de retirar las piezas de la sala de exhibición y acondicionar un espacio especial para el resguardo de la colección de cuerpos momificados. Dicha colección está conformada por veinte cuerpos en diferente estado de conservación y con características específicas. El presente estudio tiene por objeto dar cuenta de los procedimientos y las distintas etapas a considerar en un trabajo planificado y sistemático. En tal sentido, se explicitan, desde la conservación preventiva, los criterios que orientaron cada una de las etapas. El proyecto, en curso, contempla las instancias de evaluación, registro, tratamiento, definición de los contenedores y características del depósito.

  12. The educational policy field origins in Argentina: the case of Buenos Aires and La Plata Federal Universities

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    Julieta Susana Garcias Franco

    2014-07-01

    Full Text Available This paper presents partial results of an ongoing study whose objective is to map the approaches and theoretical trends in the educational policy theoretical field. More specifically, this study characterizes and describes the theoretical trends of the subject Educational Policy contents in the 50s of the last century in the Buenos Aires and La Plata Federal Universities. 46 programs were analyzed in the period 1917-1959, as well as the bibliography and theoretical background linked to the professors who were responsible for the subject. Surveying professors’ biographies, it was observed that in the period prior to the institutionalization of this field, the debate focused on the positivism or anti-positivism theoretical trends. Later on, the theoretical trends that permeated the programs from 1953 to 1954 had more distinct shades of positivism and anti-positivism than those of the beginning of the century, and three axes were observed: the national tradition, the pedagogical progressivism and the Spanish Krausism.

  13. Soil response to long-term projections of extreme temperature and precipitation in the southern La Plata Basin

    Science.gov (United States)

    Pántano, Vanesa C.; Penalba, Olga C.

    2017-12-01

    Projected changes were estimated considering the main variables which take part in soil-atmosphere interaction. The analysis was focused on the potential impact of these changes on soil hydric condition under extreme precipitation and evapotranspiration, using the combination of Global Climate Models (GCMs) and observational data. The region of study is the southern La Plata Basin that covers part of Argentine territory, where rainfed agriculture production is one of the most important economic activities. Monthly precipitation and maximum and minimum temperatures were used from high quality-controlled observed data from 46 meteorological stations and the ensemble of seven CMIP5 GCMs in two periods: 1970-2005 and 2065-2100. Projected changes in monthly effective temperature and precipitation were analysed. These changes were combined with observed series for each probabilistic interval. The result was used as input variables for the water balance model in order to obtain consequent soil hydric condition (deficit or excess). Effective temperature and precipitation are expected to increase according to the projections of GCMs, with few exceptions. The analysis revealed increase (decrease) in the prevalence of evapotranspiration over precipitation, during spring (winter). Projections for autumn months show precipitation higher than potential evapotranspiration more frequently. Under dry extremes, the analysis revealed higher projected deficit conditions, impacting on crop development. On the other hand, under wet extremes, excess would reach higher values only in particular months. During December, projected increase in temperatures reduces the impact of extreme high precipitation but favours deficit conditions, affecting flower-fructification stage of summer crops.

  14. Tidal variations of flow convergence, shear, and stratification at the Rio de la Plata estuary turbidity front

    Science.gov (United States)

    FramiñAn, Mariana B.; Valle-Levinson, Arnoldo; Sepúlveda, HéCtor H.; Brown, Otis B.

    2008-08-01

    Intratidal variability of density and velocity fields is investigated at the turbidity front of the Río de la Plata Estuary, South America. Current velocity and temperature-salinity profiles collected in August 1999 along a repeated transect crossing the front are analyzed. Horizontal and vertical gradients, stability of the front, convergence zones, and transverse flow associated to the frontal boundary are described. Strong horizontal convergence of the across-front velocity and build up of along-front velocity shear were observed at the front. In the proximity of the front, enhanced transverse (or along-front) flow created jet-like structures at the surface and near the bottom flowing in opposite directions. These structures persisted throughout the tidal cycle and were advected upstream (downstream) by the flood (ebb) current through a distance of ˜10 km. During peak flood, the upper layer flow reversed from its predominant downstream direction and upstreamflow occupied the entire water column; outside the peak flood, two-layer estuarine circulation dominated. Changes in density field were observed in response to tidal straining, tidal advection, and wind-induced mixing, but stratification remained throughout the tidal cycle. This work demonstrates the large spatial variability of the velocity field at the turbidity front; it provides evidence of enhanced transverse circulation along the frontal boundary; and reveals the importance of advective and frictional intratidal processes in the dynamics of the central part of the estuary.

  15. Leishmania (Leishmania mexicana en el corregimiento de San Matías, municipio de Gómez Plata, Antioquia, Colombia

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    Diana Sierra

    2006-10-01

    Full Text Available Introducción. La leishmaniaisis es una enfermedad encontrada en focos naturales de infección donde están presentes insectos vectores y mamíferos reservorios deLeishmania. Objetivo. Registrar por primera vez la presencia de Leishmania (Leishmania mexicana Biagi, 1953, en el corregimiento de San Matías, municipio de Gómez Plata, departamento de Antioquia. Materiales y métodos. La especie fue aislada de un paciente con leishmaniasis cutánea localizada e identificada por la técnica de Inmunofluorescencia utilizando anticuerpos monoclonales específicos de especie y electroforesis de enzimas . Resultados y conclusión. Su perfil isoenzimático similar al de las cepas de referencia L. (L. mexicana (MNCY/BZ/62/M379 y L. (L. mexicana (MHOM/BE/82/BEL21, permitió concluír que la especie aislada del paciente es L. (L. mexicana.

  16. DNA barcode of Parodontidae species from the La Plata river basin - applying new data to clarify taxonomic problems

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    Elisangela Bellafronte

    Full Text Available In the past years, DNA barcoding has emerged as a quick, accurate and efficient tool to identify species. Considering the difficulty in identifying some Parodontidae species from the La Plata basin and the absence of molecular data for the group, we aimed to test the effectiveness of DNA barcoding and discuss the importance of using different approaches to solve taxonomic problems. Eight species were analyzed with partial sequences of Cytochrome c oxidase I. The mean intraspecific K2P genetic distance was 0.04% compared to 4.2% for mean interspecific K2P genetic distance. The analyses of distance showed two pairs of species with K2P genetic divergence lower than 2%, but enough to separate these species. Apareiodon sp. and A. ibitiensis, considered as the same species by some authors, showed 4.2% genetic divergence, reinforcing their are different species. Samples of A. affinis from the Uruguay and Paraguay rivers presented 0.3% genetic divergence, indicating a close relationship between them. However, these samples diverged 6.1% from the samples of the upper Paraná River, indicating that the latter represents a potentially new species. The results showed the effectiveness of the DNA barcoding method in identifying the analyzed species, which, together with the morphological and cytogenetic available data, help species identification.

  17. Historical economic and environmental policies influencing trace metal inputs in Montevideo Bay, Río de la Plata

    International Nuclear Information System (INIS)

    Bueno, C.; Brugnoli, E.; Figueira, R.C.L.; Muniz, P.; Ferreira, P.A.L.

    2016-01-01

    Montevideo Bay is located in the middle zone of the Rio de la Plata, and since the foundation of the city, several key economic and environmental policies affected the industry, and thus, metal inputs into this ecosystem. The aim of this study is to evaluate the sedimentary geochemical record of Montevideo Bay, in order to determine the historical inputs of anthropogenic metals to the system. In addition, environmental and economic policies of the country were taken into account to infer the relationship between them and the historic metal input. Concentrations of aluminum, chromium, copper, lead, scandium and zinc were analyzed and the EF and SPI indices were calculated. The analysis showed that since Montevideo foundation, metal concentrations increased in accordance with industry development, and the indices as well as the metal concentration represent a reliable footprint of the history of different economic and environmental policies influencing historical industrial activities. - Highlights: • Trace metal record of a sediment core of Montevideo Bay/harbor was studied. • The historic inputs of metals in the area were inferred. • System degradation evolved from anthropogenic impacts. • A relationship between pollution and environmental/economic policies was discussed.

  18. DEPORTE, SOCIABILIDAD Y PARTICIPACIÓN POLÍTICA ENTRE NADADORES “MASTER” DEL CLUB UNIDOS DE LA PLATA / Sport, sociability and political participation among master swimmers of Club Unidos de La Plata

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    Julia Hang

    2014-12-01

    Full Text Available El presente trabajo se propone analizar las diversas maneras en que se establecen relaciones sociales y políticas partir de una práctica deportiva.  Se tomará el caso de un conjunto de nadadores “master” (adultos del Club Unidos de La Plata[1], quienes desde el año 2008 participan de la conducción política de la institución, para dar cuenta del modo en que se relacionan entre sí y con la política institucional del club, otorgando sentidos específicos a su participación “política”. Dado que la práctica de la natación es valorada por estos actores no sólo por su dimensión deportiva, sino principalmente por su dimensión sociable, aquí se buscará reflexionar sobre los modos en que a partir de la participación en una actividad deportiva y sociable, actores con diferentes historias y trayectorias políticas se vinculan entre sí, construyen relaciones políticas y disputan espacios de poder, tales como la presidencia del club o un lugar en la comisión directiva. A su vez, se buscará reflexionar sobre el vínculo que hubiera entre estas relaciones y otras esferas de la política local, considerando las apuestas subjetivas y los sentidos otorgados por los actores a la participación en este espacio.   Palabras Clave: deporte, sociabilidad, política, club, natación.   Abstract This paper analyzes the ways in which social and political relations are established from a sport. It will take the case of a group of "master" swimmers (adults of Club Unidos de La Plata , who since the 2008 year take part of the political leadership of the institution , to show the way they relate between each other and the institutional politics, giving specific senses to their participation in "politics" . Since the practice of swimming is valued by these actors not only for its sportive dimension , but mainly for its social dimension , here we seek to reflect on the ways from participating in a sportive and sociable practice , actors with

  19. Variaciones en la estacionalidad de polen y esporas fúngicas en la atmósfera de la ciudad de La Plata (Argentina Seasonal variation of pollen and fungal spores in the atmosphere of Plata city (Argentina

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    Daniela S Nitiu

    2011-12-01

    Full Text Available Se presentan los primeros datos sobre variaciones estacionales de polen y esporas fúngicas en su conjunto en la atmósfera de la ciudad de La Plata durante julio 2000 / junio 2001. El total de bioaerosoles fue de 201889.15 de los cuales el 15% correspondió a 54 tipos polínicos y el 85% a 79 tipos esporales. El Índice Polínico estuvo dado en un 74% por Polen Arbóreo (PA y en un 26% por Polen Herbáceo (PNA. La máxima concentración de PA tuvo lugar en septiembre con granos provenientes de Platanus y Fraxinus. El PNA presentó dos picos, el primero en diciembre procedente de Poaceae y el segundo en marzo debido a Ambrosia. Con respecto al componente fúngico, se identificaron esporas de Oomycota, Zygomycota, Myxomycota, Ascomycota y Basidiomycota. Estos bioaerosoles estuvieron presentes durante todo el año y en altas concentraciones siendo más abundantes en verano - otoño Las mitosporas de Hongos Imperfectos dominan la nube superando el 44% del total del Índice Esporal. El máximo aporte se registró en febrero dado por las esporas de Cladosporium. Se identificaron dos períodos estacionales en los cuales se hallan simultáneamente altas concentraciones de polen y esporas fúngicas. El primero se desarrolla en primavera y está integrado por Platanus, Fraxinus y Aspergillus / Penicillium y el segundo es estival e involucra a Ambrosia, Alternaria y Cladosporium.We present the first data on representativeness and seasonal variation of pollen and fungal spores as a whole in the atmosphere of the city of La Plata during july 2000 / june 2001. Total was 201889.15 bioaerosols, 15% of which was contributed by 54 pollen types and 85% by 79 spore types. The Pollinic Index came from arboreal pollen (PA in 74% and herbaceous pollen (PNA in 26%. The PA maximum concentration took place in september due to Platanus and Fraxinus. The PNA presented two peaks, one in december due to Poaceae, and the other one in march from Ambrosia. In regard to the

  20. Intersecciones entre Violencia de Género, Pobreza y Acceso a la Justicia: El Caso de la Ciudad de La Plata (Links between Gender-based Violence, Poverty and Access to Justice: The Case of the City of La Plata

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    Manuela Graciela González

    2015-06-01

    Full Text Available A critical reflection on the experience at Courts of female victims of gender violence is the aim of this paper. Provincial, national and international laws are the framework for the analysis. The raw material are their reports ( assesed from the perspective of the newest writings on the issue which stress the differences between the official discourse of the Administration of Justice and the victims' "accounts". Three different questions have been asked to guide our research: Are gender violence and poverty , factors linked to the lack of an effective Access to Justice? Which are the new factors observed everywhere and those which are present only in Latin America?Are there any changes in the social stereotypes which clear and ease the womens' path towards the administration of justice? En este artículo reflexionamos críticamente sobre la situación de las mujeres en La Plata-Argentina que padecen violencia de género cuando acceden a la administración de justicia. Para ello tomamos como marco referencial la normativa provincial, nacional e internacional. Utilizamos como insumo los testimonios de las mujeres, analizados a la luz de la literatura actual, que polemiza sobre la compleja y a veces contradictoria relación entre el discurso "oficial" de la Administración de justicia y los "relatos" de las mujeres. Nos interrogamos sobre tres ejes de trabajo que han orientado nuestra producción: ¿Qué intersecciones visualizamos entre violencia de género y pobreza como factores que obstaculizan el acceso a la justicia?¿Qué factores nuevos aparecen en contextos globalizados, y cuales son específicos de América Latina?¿Se observan cambios en los estereotipos sociales que despejan el camino de las mujeres a la administración de justicia? DOWNLOAD THIS PAPER FROM SSRN: http://ssrn.com/abstract=2611592

  1. Long term fish assemblages as units of management in a temperate estuary (Rio de La Plata - SW Atlantic Ocean

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    María Inés Lorenzo

    2011-03-01

    Full Text Available Demersal fish assemblages from trawl surveys in the Rio de la Plata estuary and its inner continental shelf were analyzed from 1975 to 1995. The first two factors of Principal Component Analysis explained 48% of the variance in species distribution, and they are consistent with the results of a cluster analysis. The analysis indicated the existence of three spatially and temporally distinct fish assemblages: internal and external estuarine and inner continental shelf (Uruguayan coastal assemblages. These assemblages were persistent considering the environmental characteristics and their species composition. Despite the changes registered in the species density during the period surveyed, the fish assemblages tend to persist over time. It was demonstrated that the assemblages can be considered as open systems and that there exists a reciprocal flow of organisms between adjacent associations. However, each assemblage showed high spatial and temporal persistence in accordance with the environmental characteristics of the system analyzed. Therefore, and according to the multispecies fisheries operating in the system, each assemblage defined could be considered a unit of management.Foram analisadas as associações dos peixes demersais provenientes de arrastos de prospecção no estuário do Rio de la Plata e sua plataforma interna no período de 1975 a 1995. Os dois primeiros fatores da Análise de Componentes Principais explicaram 48% da variância na distribuição das espécies sendo consistentes com os resultados da análise de agrupamento. Os resultados mostraram a existência de três associações de peixes espacial e temporalmente distintas: uruguaia costeira, estuarina externa e estuarina interna. Essas associações foram consistentes quanto às características ambientais e de composição de espécies. A despeito das mudanças registradas na densidade das espécies ao longo do período analisado, as associações de peixes foram

  2. Imagen y palabra en la evangelización y catequesis de la Ruta de La Plata. Potosi–Arica

    Directory of Open Access Journals (Sweden)

    Guzmán, Fernando

    2014-12-01

    Full Text Available The following article intends to recreate, by means of studying a number of wall paintings in the churches located in the “Ruta de la Plata” (Silver route trade between Potosi mining village and Arica's port, analyzing the catechisms of the Third Council of Lima (1584, the way in which the Christianization and catechesis process took place in these locations. Based in the trilogy listened word, memorized formula, and contemplated-remembered image of the religious paintings, the research purpose is focused on detecting how that particular articulation modified or determined the remembrance that the observers made of them. In addition, it will deepen in the way the paintings were observed, and in the images that were created in memory, figuring how they gave life to a particular Christian experience for the inhabitants of this territory.El presente trabajo se propone reconstruir, a través del estudio de las pinturas murales en las iglesias ubicadas en la Ruta de la Plata y del análisis de los catecismos del Tercer Concilio limense, la forma como podría haber operado el método de evangelización y catequesis fundado en la trilogía: palabra escuchada, fórmula memorizada, imagen contemplada y recordada. Buscando proponer de qué manera esa articulación modificaba o determinaba la observación o la recordación de las pinturas religiosas o, en la dirección contraria, de qué forma las pinturas observadas o la imagen de ellas en la memoria daban forma a la vida cristiana de quienes habitaban este territorio.

  3. Seroprevalencia de babesiosis bovina en la hacienda Vegas de la Clara, Gómez Plata (Antioquia, 2008

    Directory of Open Access Journals (Sweden)

    Richard Zapata Salas

    2011-06-01

    Full Text Available La babesiosis es una enfermedad del ganado bovino transmitida por la garrapata Rhipicephalus (Boophilus microplus y causada por los parásitos protozoarios Babesia bovis y B. bigemina. Una zona se considera epizootiológicamente estable frente a Babesia spp, cuando el 75% de los bovinos entre las edades de 3 a 9 meses son serorreactivos (IgG frente a Babesia bovis y Babesia bigemina y no hay evidencia de signos clínicos. El objetivo de esta investigación fue determinar la seroprevalencia de Babesia bovis y Babesia bigemina en el ganado bovino de la hacienda Vegas de la Clara (Universidad de Antioquia, Gómez Plata, Antioquia, por medio de inmunofluorescencia indirecta. Se diseñó un estudio descriptivo prospectivo con análisis de corte transversal. Fue evaluada toda la población bovina de la hacienda Vegas de la Clara (n = 118. Las muestras fueron evaluadas por inmunofluorescencia indirecta para la detección de anticuerpos tipo IgG específicos contra Babesia bovis y B. bigemina. La serorreactividad obtenida en los bovinos evaluados, para al menos una especie de Babesia fue del 89,8%, para Babesia bovis del 83,8%, mientras que para B. bigemina del 61%. Se obtuvo una relación estadísticamente significativa entre la serorreactividad para B. bigemina y la frecuencia del tratamiento garrapaticida. La serorreactividad indica estabilidad enzoótica en el hato para B. bovis, mientras que para B. bigemina se encontró que la frecuencia del tratamiento garrapaticida interrumpe su ciclo de transmisión.

  4. Avances en los métodos de recuperación de oro y plata de minerales refractarios

    Directory of Open Access Journals (Sweden)

    Parga, J. R.

    1996-08-01

    Full Text Available Recent research work in hydrometallurgical processes for precious metals recovery from refractory ores is analyzed. Advantages and applications are discussed. Likewise, two methods, one stage direct pressure oxidation/cyanidation and pyrometallurgical recovery, are also described. In the first one, gold and silver oxidation and recovery can be carried out in the same reactor simultaneously. A higher than 96 % recovery in less than 90 min can be achieved. As for the pyrometallurgical recovery method, lead paste from automotive discharged batteries is use and no sulfur dioxide is generated. A precious metals recovery higher than 96 % is reached.

    En este artículo se analizan algunos de los avances introducidos en los procedimientos hidrometalúrgicos para la recuperación de los metales preciosos contenidos en minerales refractarios y se describen sus ventajas y aplicaciones específicas. Asimismo, se muestran dos procedimientos, la cianuración oxidante a presión en una etapa y la recuperación pirometalúrgica con plomo de metales preciosos. En el proceso de cianuración oxidante a presión, la oxidación y disolución del oro y de la plata se realizan simultáneamente en el mismo reactor, con recuperaciones de ambos superiores al 96 % en 90 min. Con respecto al método de recuperación pirometalúrgica, se emplea pasta de plomo de baterías de automóviles desechadas, sin que se genere dióxido de azufre, obteniéndose también elevados valores de recuperación de los metales preciosos (> 96 %.

  5. The land Piedra Alta : A geotectonic unit in the juvenile Paleoproterozoic craton del Rio de la Plata ( Uruguay )

    International Nuclear Information System (INIS)

    Preciozzi, F.; Sanchez Bettucci, L.; Oyhantcabal, P.; Pecoits, E.; Aubet, N.; Peel, E.; Basei, M.

    2003-01-01

    Brazilian Shield (Rio Grande do Sul) where Paleoproterozoic os land, located in the region Western, are covered by Paleozoic sediments of the Paraná Basin. The Neoproterozoic domains develop east of the Precambrian shield of Uruguay. The Exceptions to this comparative correlation are represented by the Campanero Unit and Field Suspect Punta del Este, only identified in Uruguayan territory. The Piedra Alta (Río de la Plata Craton, ss.) Is composed of a complex gneissic-migmatítico plant, essentially composed of porphyritic foliated granitoids interspersed with different types of mafic rocks Paleoproterozoicas Migmatites and, at least in the southern portion, where four metamorphic belts of different degree and extent are interleaved (Montevideo, San Jose, Cerros de San Juan and Arroyo Grande). Granites, granodiorites, and bodies mafic, of different composition, age and location environment are intruding the whole ground. The last magmatic activity is represented by a swarm of dykes aged mafic ca. 1750 - 1790 Ma (Bossi and Pitched, 1991, Halls et al., 2001) and meta tuffs acid intercalated in the Belt of Los Cerros de San Juan whose ages by the method U / Pb located in the vicinity of 1753 ± 5 Ma (Preciozzi et al, in prep.). The Piedra Alta Terrane no evidence of being affected by events tectonotérmicos Neoproterozoic and is separated from the Block Valentines by the shear zone Sarandi del Yi (Preciozzi et al., 1979). From geochronological studies U / Pb, Rb / Sr, K / Ar and Sm / Nd recent, carried out on the rocks Intrusive and Piedra Alta Land gneisses, it has been possible to observe a set of events that They affected the Land

  6. IDENTIFICACIONES Y VINCULACIONES: UNA PROPUESTA DE INTERSECCIÓN PARA ANALIZAR LA MÚSICA INDIE DE LA CIUDAD DE LA PLATA (ARGENTINA)

    OpenAIRE

    Ornela Boix

    2017-01-01

    Este trabajo examina el problema de las identificaciones musicales a partir de una aproximación etnográfica a la música indie de la ciudad argentina de La Plata, basada en observaciones y entrevistas con un grupo de sellos musicales. Realiza una revisión crítica de la literatura que asume un enfoque narrativo y entiende el indie como género musical asociado a la juventud de las clases medias. En este contexto, el artículo interroga los enfo...

  7. Potencial de nanopartículas de plata inmovilizadas mediante la técnica de ultrasonido recubiertas en corcho granular como agente microbiano

    OpenAIRE

    Portillo Alejo, Daniel

    2015-01-01

    Las nanopartículas de plata (AgNPs) han sido ampliamente usadas en las últimas décadas gracias a sus aplicaciones en áreas como la catálisis y la medicina. En catálisis, los principales focos de estudio se basan en la oxidación de compuestos como metanol y etanol, como propuesta para un posible método de obtención de hidrógeno molecular. En cuanto a las aplicaciones médicas, se ha probado que las AgNPs pueden reducir significativamente muchas infecciones bacterianas. Con este tipo de nanopa...

  8. An avant-garde professorship of neurobiology in education: Christofredo Jakob (1866-1956) and the 1920s lead of the National University of La Plata, Argentina.

    Science.gov (United States)

    Théodoridou, Zoe D; Koutsoklenis, Athanasios; del Cerro, Manuel; Triarhou, Lazaros C

    2013-01-01

    The interdisciplinary trend in "Mind, Brain, and Education" has witnessed dynamic international growth in recent years. Yet, it remains little known that the National University of La Plata in Argentina probably holds the historical precedent as the world's first institution of higher education that formally included neurobiology in the curriculum of an educational department, having done so as early as 1922. The responsibility of teaching neurobiology to educators was assigned to Professor Christofredo Jakob (1866-1956). In the present article, we highlight Jakob's emphasis on interdisciplinarity and, in particular, on the neuroscientific foundations of education, including special education.

  9. Geology of the Río de la Plata and the surrounding areas of Argentina and Uruguay related to the evolution of the Atlantic margin

    Science.gov (United States)

    Rossello, Eduardo A.; Veroslavsky, Gerardo; de Santa Ana, Héctor; Rodríguez, Pablo

    2018-04-01

    An integrated study of geological and geophysical data of the Río de la Plata region and its relation to the evolution of the Atlantic passive margin is herein described. This characterization is based on the available geological and geophysical information and on the correlation of the southern end of the best-known Santa Lucía Basin in Uruguay to the Salado Basin in Argentina, and their connection through the Quilmes Trough. Furthermore, a new Meso-Cenozoic depocenter is characterized and identified as Recalada Trough, subparallely aligned to the Quilmes Trough and separated from it by the Magdalena-Montevideo High. Both sedimentary fillings present ENE-WSW trending main axes and reach an average thickness of almost 2000 m. This suggests an evolution from a triple junction where interconnected extensional arms developed, which have had common Mesozoic tectosedimentary histories related to the early opening of the Atlantic Ocean. Based on the geophysical and geological evidence, the previously accepted existence in the Río de la Plata of a first-order structural feature along the international border between Argentina and Uruguay, associated to an ENE-WSW trending tectonic high, identified as Martín García, is unjustified. The tectonic evolution of the Atlantic margin in front of the Río de la Plata estuary is the consequence of a long deformation history starting in the Precambrian up to recent times. Each Precambrian, Paleozoic, Mesozoic and Cenozoic tectonic scenario adds different weak trends on the continental crust, which control the evolution of the sedimentary depocenters. The presence of these tectosedimentary records influence the bathymetric control of the Río de la Plata and the dynamics of the recent estuarine deposits. The Meso-Cenozoic sedimentary infill is estimated to comprise considerable ranges of sandstones and conglomerates associated with faulted blocks of the crystalline basement, with expected petrophysical conditions oscillating in

  10. Analysis of Current and Future SPEI Droughts in the La Plata Basin Based on Results from the Regional Eta Climate Model

    Directory of Open Access Journals (Sweden)

    Alvaro Sordo-Ward

    2017-11-01

    Full Text Available We identified and analysed droughts in the La Plata Basin (divided into seven sub-basins for the current period (1961–2005 and estimated their expected evolution under future climate projections for the periods 2011–2040, 2041–2070, and 2071–2099. Future climate projections were analysed from results of the Eta Regional Climate Model (grid resolution of approximately 10 km forced by the global climate model HadGEM2-ES over the La Plata basin, and considering a RCP4.5 emission scenario. Within each sub-basin, we particularly focused our drought analyses on croplands and grasslands, due to their economic relevance. The three-month Standardized Precipitation Evapotranspiration Index (SPEI3 was used for drought identification and characterization. Droughts were evaluated in terms of time (percentage of time from the total length of each climate scenario, space (percentage of total area, and severity (SPEI3 values of cells characterized by cropland and grassland for each sub-basin and climate scenario. Drought-severity–area–frequency curves were developed to quantitatively relate the frequency distribution of drought occurrence to drought severity and area. For the period 2011–2040, droughts dominate the northern sub-basins, whereas alternating wet and short dry periods dominate the southern sub-basins. Wet climate spread from south to north within the La Plata Basin as more distant future scenarios were analysed, due to both a greater number of wet periods and fewer droughts. The area of each sub-basin affected by drought in all climate scenarios was highly varied temporally and spatially. The likelihood of the occurrence of droughts differed significantly between the studied cover types in the Lower Paraguay sub-basin, being higher for cropland than for grassland. Mainly in the Upper Paraguay and in the Upper Paraná basins the climate projections for all scenarios showed an increase of moderate and severe droughts over large regions

  11. Análisis de la morosidad tributaria de las empresas aplicando técnicas borrosas y estadísticas. El caso de Mar del Plata

    OpenAIRE

    Mallo, Paulino E.; Artola, María Antonia; Zanfrillo, Alicia Inés; Morettini, Mariano; Galante, Marcelo Javier; Busetto, Adrián Raúl; Pascual, Mariano Enrique

    2006-01-01

    El propósito del presente trabajo es caracterizar el comportamiento de los indicadores contables de distintas empresas de pequeña y mediana envergadura del medio socioproductivo de la ciudad de Mar del Plata que puedan incidir en la determinación de la morosidad en el pago de tributos, sean nacionales, provinciales o municipales, a través de la aplicación de lógica difusa. Para ello se trabajó con una muestra de empresas representativas de distintos sectores productivos y comerciales de la ci...

  12. Caracterización y tratamiento de la inundación urbana: el caso de la cuenca del arroyo del Gato en el partido de La Plata

    OpenAIRE

    Romanazzi, Pablo Gustavo

    2011-01-01

    Las inundaciones que se producen en la cuenca media del arroyo del Gato afectan a gran parte del casco fundacional de la ciudad de La Plata y barrios aledaños. El sistema de desagües pluviales presenta en la actualidad graves deficiencias para conducir los excedentes superficiales generados aún por tormentas de baja severidad. Este es un caso de estudio típico de la problemática de la inundación urbana, donde el crecimiento periférico de la ciudad no fue anticipado por una planificación adecu...

  13. Seasonal and inter-annual turbidity variability in the Rio de la Plata from 15 years of MODIS: El Niño dilution effect

    OpenAIRE

    Dogliotti, A.I.; Ruddick, K.; Guerrero, R.

    2016-01-01

    Spatio-temporal variability of turbidity in the Río de la Plata (RdP) estuary (Argentina) at seasonal and inter-annual timescales is analyzed from 15 years (2000–2014) of MODIS data and explained in terms of river discharges and the El Niño Southern Oscillation (ENSO). Satellite estimates were first validated using in situ turbidity measurements and then the time series of monthly averages were analyzed to assess the seasonal and inter-annual variability of turbidity. A strong seasonal variab...

  14. La industria naval de la ciudad de Mar del Plata. Situación de las PyMEs y de las grandes empresas

    OpenAIRE

    Zini, José María

    2013-01-01

    El objetivo de este trabajo es brindar una descripción cualitativa de la problemática que hoy posen la pequeñas empresas del sector del Industria Naval en la ciudad de Mar del Plata en relación a los grandes grupos económicos que dominan la actividad pesquera y que afectan directamente al normal funcionamiento de estas PyMEs, teniendo en cuenta que denominamos Pymes a aquellas empresas que facturan anualmente hasta $15.000.000 y desde ese valor en adelante las llamamos Grandes Empresas. La in...

  15. Madres 'desincrustadas'. El uso de Internet y la compra de juguetes en la maternidad del nuevo milenio en La Plata, Argentina

    OpenAIRE

    Castilla, Mar??a Victoria

    2008-01-01

    El objetivo del texto es analizar las formas en que se reflejan los cambios sociales vinculados con la modernidad "tard??a" en las experiencias de las madres, tomando como caso a la ciudad de La Plata, Argentina. Para ello, se realizaron 30 entrevistas en profundidad a madres de dos generacionales (1970 y 2000) de nivel socioecon??mico medio. Dentro de los principales hallazgos, se menciona la persistencia de un modelo tradicional de distribuci??n de los roles, con rasgos de crianza modernos ...

  16. Metodología para recuperar metales preciosos: Oro, plata y grupo del platino, presentes en desechos electrónicos

    OpenAIRE

    Oliveros Gómez, Honorio

    2011-01-01

    Se desarrolló a nivel de laboratorio una metodología de extracción de los metales preciosos oro, plata y del grupo del platino (platino, paladio, iridio y rodio) presentes en desechos electrónicos. Para determinarla, se indagó el estado del arte en la recuperación de metales a partir de desechos electrónicos, se desensamblaron componentes electrónicos, se caracterizó el material electrónico mediante técnicas analíticas de microscopia electrónica de barrido “Scanning electron microscope” SEM, ...

  17. Efecto de la plata sobre el proceso de síntesis por fusión de un pigmento del tipo azul ultramarino

    OpenAIRE

    Castillo, Wilmer; González, Luis; Sánchez, Selene; Ocanto, Freddy; Linares, Carlos F

    2011-01-01

    Se realizó la síntesis de pigmentos inorgánicos del tipo azul ultramarino a partir de la mezcla de zeolita A, carbonato de sodio, azufre elemental y contenido de plata entre un 0 al 5% p/p a una temperatura de 800°C por espacio de 4h. Los sólidos fueron caracterizados por la técnicas de difracción de rayos X (DRX), infrarrojo con transformada de Fourier (FTIR) y espectroscopia de reflectancia de UV a fin de verificar la estructura y coloración de los materiales obtenidos. Los resultados mostr...

  18. La intervención anglo-francesa en el Río de la Plata entre 1847 y 1851. Un intento frustrado

    OpenAIRE

    Jaime Collazo Odriozola

    2007-01-01

    En la quinta década del siglo XIX, Gran Bretaña y Francia intervinieron en el conflicto entre los bandos políticos hegemónicos en el Río de la Plata, asumiendo la defensa del gobierno de Montevideo, recluido en los límites de la ciudad. El enfrentamiento era con los federales, particularmente con el gobierno de la ciudad de Buenos Aires y los encargados de las Relaciones Exteriores de las provincias argentinas, encabezado por Juan Manuel de Rosas, quizá la figura más controvertida en la histo...

  19. [Mucormycosis: Study of five cases found in San Juan de Dios hospital and Sor Maria Ludovica hospital in La Plata, Argentina].

    Science.gov (United States)

    Featherston, P L; Fernández, G; Munguía, H; Marín, M E

    1998-01-01

    Hospital San Juan de Dios and Sor María Ludovica in La Plata, between 1980 and 1997. Mucormicosis is a frequently fatal, opportunistic fungal infection, that affects immunocompromised patients. The risk factors include diabetes mellitus, leukemia, lymphoma, burns, etc. We present three cases of cutaneous mucormicosis in children 3, 10 and 11 years old, who had been sent to the hospital due to compound fractures in a car crash; one case of pulmonary mucormicosis in an adult 28 years old with prolonged corticotherapy and rhinocerebral mucormicosis in a patient 38 years old with a diagnosis of acute lymphoid leukemia.

  20. Estudios etnobotánicos en la conurbación Buenos Aires-La Plata, Argentina: Productos de plantas medicinales introducidos por inmigrantes paraguayos

    OpenAIRE

    Julio A. Hurrell; Jeremías P. Puentes; Patricia M. Arenas

    2017-01-01

    Este trabajo incluye resultados parciales de una línea de investigación en Etnobotánica urbana, que estudia los conocimientos locales sobre las plantas, sus partes y productos derivados en la conurbación Buenos Aires-La Plata. Se incluyen productos de plantas medicinales de reciente ingreso en el área de estudio a través de inmigrantes oriundos de Paraguay. Los productos corresponden a 10 especies: Achyrocline alata(“jateí-ka’á”), Baccharis gaudichaudiana (“jaguareté-ka’á”), Cuphea lysimachio...

  1. Área de Arte y Salud del Hospital de Niños Sor María Ludovica de La Plata

    OpenAIRE

    Iriart Urruty, Andrea

    2014-01-01

    El Hospital de Niños “Sor María Ludovica” de la ciudad de La Plata, a partir de la firma de la disposición N° 940/13 por parte de la dirección del mismo, funciona el “Área de Arte y Salud” integrada por el Servicio Social, el Servicio de Salud Mental del Hospital, la Biblioteca Ambulante, el Taller de Plástica y Literatura y el Laboratorio de Arte que desarrolla el Grupo La Grieta. Esta área es un espacio institucional abocado a aunar criterios y conjugar inquietudes en torno al papel del ...

  2. Influencia de las Condiciones de Acceso a los Servicios Financieros y su Relación con el Crecimiento de las Micro y Pequeñas Empresas Peruanas que Exportan Joyería de Plata, Lima, 2012 - 2014

    OpenAIRE

    Mendoza Aranzamendi, Jessica Aleida

    2017-01-01

    La presente investigación tuvo como objetivo analizar las condiciones de acceso a los servicios financieros y su influencia en el crecimiento de las Micro y Pequeñas Empresas peruanas que exportan joyería de plata. Las unidades de análisis son las Micro y Pequeñas Empresas que exportan joyería de plata. Se trata de una investigación relacional, de campo y comparativa (al comparar las tasas de crecimiento de estas MYPES con las que han obtenido las grandes empresas que pertenecen al sector exp...

  3. Informe Ana Libertad Baratti de la Cuadra : Informe de Radio Universidad Nacional de La Plata sobre la recuperación de la nieta número 115, por Abuelas de Plaza de Mayo

    OpenAIRE

    Pigeau, Nora; Barnes de Carlotto, Estela; Lovazzano, Eduardo; Velazco, Luis; Cuadra, Estela de la; Cardoso, Miriam

    2014-01-01

    Informe de Radio Universidad Nacional de La Plata sobre el hallazgo de la nieta número 115, recuperada por Abuelas de Plaza de Mayo: Ana Libertad Baratti de la Cuadra. El 22 de agosto de 2014 la ciudad de La Plata y el país entero celebró el encuentro de la nieta de la co-fundadora y primera presidenta de la Asociación Abuelas de Plaza de Mayo, Alicia “Licha” Zubasnabar de De la Cuadra: apareció Ana Libertad Baratti de la Cuadra. Héctor Carlos Baratti y de Elena de la Cuadra fueron se...

  4. Efectividad clínica del apósito hidrocoloide versus sulfadiazina de plata en el manejo de quemaduras superficiales. Clínica Internacional 2014-2015

    OpenAIRE

    Vásquez Chávez, Elva

    2015-01-01

    Comparar la efectividad clínica del uso del apósito hidrocoloide vs sulfadiazina de plata en el manejo de quemaduras superficiales de espesor parcial. Este estudio es observacional analítico. 62 pacientes divididos aleatoriamente en grupo de apósito hidrocoloide (DuodermR) o silverdiazina de plata, fueron seguidos hasta presentar una reepitelización completa. Se evaluó las siguientes variables clinico-epidemiológicas: edad, sexo, tipo de tratamiento, localización, tiempo y calidad de epiteliz...

  5. Las nuevas tendencias en gestión municipal : Propuesta de un modelo de administración turística para el Municipio de La Plata, provincia de Buenos Aires

    OpenAIRE

    Molinari, Gloria Edith

    2012-01-01

    Con el presente trabajo propongo la factibilidad de aplicar un modelo de gestión comúnmente utilizado en las organizaciones privadas a los organismos públicos, en este caso dedicados a la actividad turística. Nos concentraremos en la gestión Municipal del turismo en la ciudad de La Plata. Para ello, utilicé el Manual de Directrices de Municipios Turísticos de la SECTUR, aplicado a la Dirección de Turismo de la Municipalidad de La Plata, con el fin de evaluar diferentes aspectos de l...

  6. LAS IMPLICANCIAS ARQUEOLÓGICAS DEL DIARIO DE PERO LOPES DE SOUSA (1531 DURANTE SU VIAJE AL RÍO DE LA PLATA Y AL DELTA INFERIOR DEL RÍO PARANÁ / The archaeological implications of the Diary of Pero Lopes de Souza (1531 during his trip to the La Plata Riv

    Directory of Open Access Journals (Sweden)

    Gustavo Politis

    2014-12-01

    Full Text Available Normal 0 21 false false false ES-AR X-NONE X-NONE En este trabajo se estudia el diario del explorador portugués Pero Lopes de Souza en 1531 al Río de la Plata y al delta Inferior del río Paraná desde una perspectiva histórica y arqueológica. Este relato es el único documento de la época escrito en tiempo real por un testigo directo de los acontecimientos que describe y por lo tanto es una fuente de calidad superlativa para conocer los primeros momentos de la exploración europea en el Río de la Plata y para abordar el estudio de los indígenas que habitaban el área a principios del siglo XVI. En este artículo se resumirán y discutirán las observaciones de Lopes de Sousa en el contexto de la historia del Río de La Plata en la primera mitad del siglo XVI y de las investigaciones arqueológicas recientes.   Palabras clave: chana-timbú, arqueología del NEA, crónicas siglo XVI       Abstract In this paper the diary of the Portuguese explorer Pero Lopes de Sousa to the La Plata River and to the Lower Delta of the Paraná River is analyzed from a historical and archaeological perspective. This narrative is the only document written in real time from a direct witness of the accounts he described. Therefore it is a unique high-quality source to know about the early times of the European Conquest to the La Plata River and to approach the study of the indigenous people of the area at the beginning of the XVI Century. In this article, the observations and comments from Lopes de Souza are summarized and analyzed within the context of the history of the first half of the XVI Century and in the light of the recent archaeological investigations. Keywords: chaná-timbú, archaeology of Northeastern Argentina, XVI Century Chronicles 

  7. Mar del Plata (Argentina y Málaga (España. Estudio comparado de dos destinos turísticos

    Directory of Open Access Journals (Sweden)

    Fernando Almeida García

    2014-01-01

    Full Text Available Se estudia y compara la evolución de dos destinos que presentan similitudes en su historia turística, en su tamaño demográfico y función territorial. A pesar de las similitudes de Málaga y Mar del Plata, éstas presentan comportamientos singulares en su evolución. Se toma como referencia de estudio el modelo de Butler. En el caso de Málaga es esencial conocer la relación que ha mantenido con Torremolinos y la Costa del Sol, para poder entender la evolución del destino. En el caso de Mar del Plata es importante entender el papel de la demanda nacional y las decisiones políticas que derivaron en la popularización del destino. Así mismo, se analiza el papel que ha jugado las segundas residencias y los procesos de urbanización en la evolución de los destinos turísticos.

  8. El sudor del sol y las lágrimas de la luna : la metalurgia del oro y de la plata en el antiguo Perú

    Directory of Open Access Journals (Sweden)

    Cruz García de la Torre

    1999-01-01

    Full Text Available El oro y la plata fueron los metales cuyo hallazgo en el continente americano despertó grandes espectativas de riqueza en la menta de los primeros conquistadores, incluso antes de su descubrimiento. Los cronistas aportan abundantes noticias no sólo sobre las fabulosas riquezas metálicas que poseía el Perú sino, incluso, sobre los diferentes procesos tecnológicos que tuvieron lugar desde la extracción de ambos metales hasta su transformación en objetos suntuarios, así como sobre el valor y significado que tuvieron el oro y la plata en el Perú prehispánico.The finding of gold and silver in the american continent raised great expectations of wealth among the conquerors. The chronicles provide a detailed account not only of the fabulous richness in metals of Peru, but also of the technological process of extraction and of the transformation of these metals in luxury objects. Through them we learn about the simbolic meaning of gold and silver in prehispanic Peru.

  9. The student movement at the Universidad Nacional de La Plata before the "Revolución Libertadora": actors, transformations and conflicts between September, 1955 and May 1956

    Directory of Open Access Journals (Sweden)

    Nayla Pis Diez

    2016-07-01

    Full Text Available In this paper we intend to approach the events that marked the institutional and political dynamics of the Universidad Nacional de La Plata (UNLP between the months of September 1955 and May 1956, with special emphasis on the student movement. We'll use written sources as documentary material to revisit the first months of the postperonist UNLP, taking into account three aspects of the ongoing process: in the first place, the process of reconstruction and desperonización of university structures, teachers and administration. In second place, we explore which was the role of the student movement: what actions it carried out, which were the internal differences and the main debates. As is known, the process of university normalization went through a disruptive moment beginning 1956: the enactment of the decree-law no. 6.403, and in particular its article no. 28, would cause massive mobilizations (both in its favor and against, numerous outlets and even strong incidents in La Plata streets. The last lines of the work will be devoted to this third aspect of the indicated period

  10. IDENTIFICACIONES Y VINCULACIONES: UNA PROPUESTA DE INTERSECCIÓN PARA ANALIZAR LA MÚSICA INDIE DE LA CIUDAD DE LA PLATA (ARGENTINA

    Directory of Open Access Journals (Sweden)

    Ornela Boix

    2017-01-01

    Full Text Available Este trabajo examina el problema de las identificaciones musicales a partir de una aproximación etnográfica a la música indie de la ciudad argentina de La Plata, basada en observaciones y entrevistas con un grupo de sellos musicales. Realiza una revisión crítica de la literatura que asume un enfoque narrativo y entiende el indie como género musical asociado a la juventud de las clases medias. En este contexto, el artículo interroga los enfoques subculturalistas, donde el indie es un ethos o una actitud, y las perspectivas bourdieanas, para las cuales el indie es un recurso de distinción. El artículo muestra las limitaciones de es tos análisis y propone una relación de intersección entre la crítica contemporánea del concepto de identidad y una perspectiva sensible a las vinculaciones involucradas en la producción de música. Así, el artículo describe al indie de la ciudad de La Plata en sus vinculaciones específicas: con la universidad, con los lugares de performance, con las nuevas tecnologías, con la ciudad, con los instrumentos musicales. Para concluir, afirma que estos elementos deben incorporarse al estudio de las identificacione s musicales.

  11. Seasonal composition, abundance and biomass of the subestuarine fish assemblage in Solís Chico (Río de la Plata estuary, Uruguay).

    Science.gov (United States)

    Plavan, A Acuña; Gurdek, R; Muñoz, N; Gutierrez, J M; Spósito, M; Correa, P; Caride, A

    2017-01-01

    The large estuaries can present long narrow branches called subestuaries or tidal creeks. These types of subsystems are distributed along the Uruguayan coast of the Río de la Plata estuary and are very important as nursery and refuge areas for fish. For the first time, the seasonal composition and abundance of the fish community of the Solís Chico subestuary was studied by using beach and gill nets. Fourteen species, mainly euryhaline (86%) presented a significant representation of juvenile stages. The fish community was dominated by Odontesthes argentinensis, Platanichthys platana, Mugil liza, Brevoortia aurea, Micropogonias furnieri and Paralichthys orbignyanus, similar to adjacent subestuaries. While Micropogonias furnieri and B. aurea were the most abundant species, some other species were rarely caught. A seasonal variation of the fish assemblage abundance was detected, with higher values in autumn showing a positive correlation with temperature. Species that complete their life cycle in the Río de la Plata estuary, some of which are relevant to fisheries (64% of the analyzed species) were captured in the Solís Chico subestuary. The importance of this environment as a transitional system for some estuarine fish species is advised.

  12. Cambios históricos en el aporte terrígeno de la cuenca del Río de la Plata sobre la plataforma interna Uruguaya

    Science.gov (United States)

    Marrero, Analía; Tudurí, Adriana; Pérez, Laura; Cuña, Caroline; Muniz, Pablo; Lopes Figueira, Rubens; Michaelovitch de Mahiques, Michel; Alves de Lima Ferreira, Paulo; Pittauerová, Daniela; Hanebuth, Till; García Rodríguez, Felipe

    2014-12-01

    El Río de la Plata (RdlP) presenta significativas variaciones naturales (hidrodinámicas y oceanográficas) asociadas a diferentes condiciones climáticas. El propósito de este trabajo es inferir los cambios de aportes continentales de sedimentos y su relación con las variaciones hidrológicas del Río de la Plata, a través del análisis de proxies sedimentológicos y geoquímicos en testigos de sedimentos de la plataforma interna uruguaya que registran los últimos 100 años, aproximadamente. A partir de la datación por 210Pb de dos testigos de sedimentos (GeoB 13813-4 y BAR1) se reconstruyó la geocronología del ambiente, y se relacionó con datos de las forzantes climáticas Pacific Decadal Oscillation, El Niño/La Niña Southern Oscillation, Atlantic Multidecadal Oscillation, y las anomalías hidrológicas de los ríos Paraná y Uruguay. Los valores más positivos y estables del Southern Oscillation Index, los cuales corresponden a fases La Niña, se observan en el periodo correspondiente entre 1910-1970, respecto al resto de la serie, donde se aprecia una mayor variabilidad y una tendencia hacia valores más negativos (eventos El Niño). Se hicieron dendrogramas (clustering) jerárquicos para ambos testigos. Para el testigo GeoB 13813-4, se utilizó la relación Ca/Ti y la granulometría, mientras que para BAR1 se recurrió a variables granulométricas y la tasa de sedimentación. El mayor aporte continental hacia la región de la plataforma adyacente al Río de la Plata registrado a partir del año 1970, podría ser el factor principal de los agrupamientos observados en los clusters para ambos testigos. Las agrupaciones mostraron una diferenciación en la década de 1970, lo que estaría asociado al aumento de los caudales de los ríos Paraná y Uruguay, durante las últimas tres décadas del siglo XX. Por otra parte se observa que la granulometría del testigo BAR1 presentó un mayor tamaño de grano y más variabilidad que en el caso del testigo Geo

  13. Mesoproterozoic evolution of the Río de la Plata Craton in Uruguay: at the heart of Rodinia?

    Science.gov (United States)

    Gaucher, Claudio; Frei, Robert; Chemale, Farid; Frei, Dirk; Bossi, Jorge; Martínez, Gabriela; Chiglino, Leticia; Cernuschi, Federico

    2011-04-01

    Mesoproterozoic volcanosedimentary units and tectonic events occurring in the Río de la Plata Craton (RPC) are reviewed. A belt consisting of volcanosedimentary successions exhibiting greenschist-facies metamorphism is exposed in the eastern RPC (Nico Pérez Terrane) in Uruguay. The Parque UTE Group consists of basic volcanics and gabbros at the base (1,492 ± 4 Ma, U-Pb on zircon), carbonates in its middle part and interbedded carbonates, shales and acid volcanics (1,429 ± 21 Ma, U-Pb on zircon) at the top. The Mina Verdún Group is made up of rhyolites and acid pyroclastics at its base and top, and Conophyton-bearing limestones and massive dolostones in the middle. A U-Pb LA-ICP MS zircon age of 1,433 ± 6 Ma is reported here for lapilli-tuffs at the base of the Mina Verdún Group (Cerro de las Víboras Formation). This age shows that the Mina Verdún Group immediately postdates the Parque UTE Group, a fact supported by carbon isotope chemostratigraphy. Both units were deformed and metamorphosed between 1.25 and 1.20 Ga, as shown by K-Ar and Ar-Ar ages. This tectonic event affected most of the RPC and led to the accretion of the Nico Pérez Terrane to the remainder of the RPC along the Sarandí del Yí megashear. We report a U-Pb LA-ICP MS zircon age (upper intercept) of 3,096 ± 45 Ma for metatonalites of the La China Complex (Nico Pérez Terrane), which yield a lower intercept age of 1,252 Ma. A proto-Andean, Mesoproterozoic belt is envisaged to account for abundant Mesoproterozoic detrital zircon ages occurring in Ediacaran sandstones of the RPC. If the RPC is fringed at both sides by Mesoproterozoic, Grenville-aged belts it is likely that it occupied a rather central position in Rodinia. A possible location between Laurentia and the Kalahari Craton, and to the south of Amazonia, is suggested.

  14. The first Uruguayan geological and pale ontological in Uruguay: memories about recent Rio de la Plata formation was been concluded from their shell fossils by D.A. Larranaga

    International Nuclear Information System (INIS)

    Martinez, S.

    1998-01-01

    The first Uruguayan geological and pale ontological manuscript, al thought published later, is the Memorial geological about recent formation of Rio de la Plata deduced from their shell fossils, written by Damaso Antonio Larranaga, probably in 1819.This opus is commended here. (author)

  15. Estudio y caracterización de nuevas emulsiones de haluro de plata como materiales de registro holográfico

    Directory of Open Access Journals (Sweden)

    Neipp, C.

    2000-08-01

    Full Text Available One of the most interesting techniques for the production of holographic optical elements is silver halide sensitised gelatin (SHSG. It combines the high sensitivity of photographic emulsions with the well-known low scattering and high diffraction efficiencies corresponding to dichromated gelatin. In this work we made a comparative study on SHSG holograms recorded on three different red sensitive emulsions: Agfa 8E75 HD, Slavich PFG-01 and BB-640 . The influence of the degree of hardening of the gelatin and the size and concentration of silver halide grains in the SHSG proccess is studied. And we will show that real high diffraction efficiencies can be obtained when using BB-640 and Slavich PFG-01 plates for recording phase transmission holograms (as high as 93% for PFG-01 and 90% for BB-640, allowing for reflections. Our investigations reveal that PFG-01 and BB-640 emulsions are not only a substitution to Agfa material, but may offer better results at a moment in which Agfa has stopped its production of holographic material.

    Una de las técnicas más interesantes para la obtención de elementos ópticos holográficos es la gelatina sensibilizada de haluro de plata (GSHP. Esta técnica combina la alta sensibilidad de las emulsiones fotográficas con los conocidos altos rendimientos en difracción y bajos niveles de scattering correspondientes a la gelatina dicromatada. En este trabajo se ha hecho un estudio comparativo sobre hologramas en gelatina sensibilizada de haluro de plata registrados en tres emulsiones diferentes sensibles al rojo: Agfa 8E75 HD, Slavich PFG-01 y BB-640. En dicho estudio se ha analizado la influencia del grado de endurecido de la gelatina y la concentración y el tamaño de los granos de haluro de plata en el procesado GHSP. Se obtuvieron rendimientos en difracción realmente altos cuando se utilizaron las placas BB-640 y Slavich PFG-01 para el registro de hologramas de fase por transmisión (tan altos como el 93

  16. La pesca artesanal en la Cuenca del Plata (Argentina y sus implicancias en la conservación de la biodiversidad Artisanal fish at del Plata basin (Argentina and its implications for the biodiversity conservation

    Directory of Open Access Journals (Sweden)

    Juan Miguel Iwaszkiw

    2011-06-01

    Full Text Available El objetivo del presente trabajo es considerar distintos aspectos que surgen del análisis de las exportaciones pesqueras provenientes de la pesca comercial artesanal de la Cuenca del Plata, Argentina. Se trata de identificar aquellos impactos vinculados a las prácticas pesqueras sobre las poblaciones naturales involucradas y los compromisos relacionados con la conservación de la biodiversidad de la ictiofauna de la cuenca. Se analizan 17 años de datos de las pesquerías comerciales artesanales correspondientes al tramo argentino del río Paraná sobre registros oficiales de los productos pesqueros exportados para distintas especies durante el período 1994-2010. Los registros de los productos exportados expresados en toneladas en peso (ton se refieren particularmente a especies autóctonas de gran tamaño e interés comercial como el sábalo (Prochilodus lineatus, la boga (Leporinus obtusidens, la tararira (Hoplias malabaricus, el surubí (Pseudoplatystoma spp., el dorado (Salminus brasiliensis y el patí (Luciopimelodus pati, además de varias especies acompañantes en las capturas como bagres, armados y pejerreyes (Odontesthes bonariensis. Las exportaciones pesqueras muestran un incremento sumamente importante con un total de 331.517 ton para el período 1994-2010. La especie blanco de la pesquería es el sábalo con 88,77 % de las exportaciones totales y le siguen en orden de importancia la tararira con el 4,16 %, la boga con el 3,70 %, el patí con un 1,35 % y otras especies de menor captura. Los países de destino de los productos pesqueros son Brasil, Colombia, Bolivia y Nigeria, entre otros. Sin embargo, desde el 2003, Colombia compra en promedio el 50 % del total de las exportaciones pesqueras de la Argentina. El análisis de los datos históricos de las exportaciones pesqueras (1994-2010 evidencia la necesidad de implementar medidas mas claras sobre el control y manejo de los recursos pesqueros y las posibles implicancias derivadas

  17. Characterization of the rock salt for the design of underground storage in saline domes; Caracterizacion de la roca sal-gema para el diseno de almacenamientos en domos salinos

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Meyenberg, Lucia [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1988-12-31

    The saline domes are natural geological formations, that have been formed in the underground, through the passage of millions of years. In Europe, they are used for hydrocarbon storage; for instance France is planning to increase, in a short term, its crude storing capacity in domes of 5 to 10 millions cubic meters (60 million of barrel), holding capacity. Additionally, studies are being conducted on the stability of this type of domes, for the storage of nuclear wastes during 100 thousand or 1 million years. [Espanol] Los domos salinos son formaciones geologicas estructurales naturales, que se han constituido en el subsuelo, en el transcurso de millones de anos. En Europa, se aprovechan para almacenar hidrocarburo; por ejemplo, Francia planea aumentar, a corto plazo, su capacidad de almacenamiento de crudo en domos de 5 a 10 millones de metros cubicos (60 millones de barriles). Ademas, se realizan estudios de estabilidad en este tipo de domos, para almacenar desechos nucleares durante 100 mil o 1 millon de anos.

  18. Characterization of the rock salt for the design of underground storage in saline domes; Caracterizacion de la roca sal-gema para el diseno de almacenamientos en domos salinos

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Meyenberg, Lucia [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1987-12-31

    The saline domes are natural geological formations, that have been formed in the underground, through the passage of millions of years. In Europe, they are used for hydrocarbon storage; for instance France is planning to increase, in a short term, its crude storing capacity in domes of 5 to 10 millions cubic meters (60 million of barrel), holding capacity. Additionally, studies are being conducted on the stability of this type of domes, for the storage of nuclear wastes during 100 thousand or 1 million years. [Espanol] Los domos salinos son formaciones geologicas estructurales naturales, que se han constituido en el subsuelo, en el transcurso de millones de anos. En Europa, se aprovechan para almacenar hidrocarburo; por ejemplo, Francia planea aumentar, a corto plazo, su capacidad de almacenamiento de crudo en domos de 5 a 10 millones de metros cubicos (60 millones de barriles). Ademas, se realizan estudios de estabilidad en este tipo de domos, para almacenar desechos nucleares durante 100 mil o 1 millon de anos.

  19. La construcción de la imagen de la ciudad. Mar del Plata y la apropiación del espacio frente al mar La construction de l'image de la ville. Mar del Plata et l'appropriation de l'espace face à la mer The construction of the city image. Mar del Plata and the appropriation of the space facing the sea

    Directory of Open Access Journals (Sweden)

    Graciela Iris Zuppa

    2011-08-01

    Full Text Available Cette étude propose une lecture interprétative de l’histoire urbaine et culturelle de Mar del Plata, un territoire dont le paysage côtier a connu d’importances modifications. Dans ce contexte de transformation, l’article étudie les pratiques publicitaires qui contribuent à la compréhension des caractéristiques de cet endroit, dans le but de proposer des interprétations autour des changements dans la construction de l’image de la ville, les représentations sociales qui les supportent,  les codes visuels et discursifs utilisés pour les transmettre.Pour atteindre ces objectifs, l’auteur analyse les émetteurs de messages, les images et les textes qui les accompagnent, le lien entre les deux instances, et l’interprétation qui émane d’elles. La récupération et la lecture interprétative de pièces graphiques, élaborées pour promouvoir la ville, permettent d’identifier et d’interpréter les caractéristiques fondamentales de la transition d’une station balnéaire élitiste qui devient une station qui se popularise. Par conséquent, l’étude des images successives de Mar del Plata entre 1930 et 1945 permet de suivre l’évolution de la station à travers les différentes campagnes definies par les politiques touristiques du gouvernement et les entreprises privées.This work proposes an interpretative reading of the urban and cultural history of Mar del Plata, a territory whose coastal scenery has been modified in a very important way. Once in this transformational context, we will analyse the advertising practices that contribute to understand the characteristics of the area, in order to offer an interpretation of the changes undergone in the construction of the city image, the social representations that support them and the visual and discursive codes used to transmit them.In order to achieve those aims, we are going to analyse the producers of those messages, the images and the written texts that are included

  20. El Astero de plata

    Directory of Open Access Journals (Sweden)

    Edmundo Motta Zamalloa

    1988-12-01

    Full Text Available Tres propósitos animan al presente trabajo: mostrar la conversión del toro en una entidad cultural a partir de un contexto definido económica y socialmente por el agrarismo, en el que el elemento toro se constituyó históricamente en la fuerza de tracción más importante entre los instrumentos de producción. De otra parte, cómo la capitalización de la agricultura y la secuela de modernización termina por transferir el control de este espectáculo a una burguesía agraria. Y, finalmente, su empleo metafórico en una relación social de tipo conflictivo.

  1. Dr. Alberto Albornoz Plata

    Directory of Open Access Journals (Sweden)

    Zoilo Cuellar Montoya

    2009-01-01

    Full Text Available

    A pesar de la diferencia de edades que nos separaba generacionalmente existió, entre Alberto y quien esto escribe, una estrecha amistad, que sobrepasa, en el momento de su dolorosa desaparición, los cuarenta y siete años, pues se originó, al impulso de vínculos familiares con su primera esposa, Doña Cecilia Ucrós de Albornoz, en la época en que yo culminaba mi carrera de medicina, cuando se inició la gran amistad que nos ha unido, desde entonces, con su hija Margarita y algo después, cuando él ocupaba el cargo de Director Científico de PFIZER de Colombia.

    En el año de 1963, en virtud de mi interés por realizar, como trabajo de tesis, un estudio de investigación sobre hepatitis experimental en perros, estudio respaldado por dicho laboratorio, debí ponerme en contacto con Alberto, en varias oportunidades, con el fin de planear el proyecto, de común acuerdo.

    Desafortunadamente, el trabajo se frustró y pasaron varios años antes de que nos volviéramos a ver. Fue con ocasión de la muerte de Cecilia que nos vimos de nuevo y, algo más tarde, en la Academia Nacional de Medicina, a partir de 1980, cuando volvimos a compartir intereses y a reafianzar nuestra amistad. Siempre admiré la distinción de Alberto, su impecable pulcritud, tanto en el vestir como, fundamentalmente, en su actuar, en sus maneras y en su trato, clásico de un caballero a carta cabal, como lo era él, porte que se mantenía constante, en su ejercicio profesional igual que en su relación con los colegas, con los pacientes, con sus discípulos, con los amigos y con los íntimos. Cómo admiré su ciencia, su alto profesionalismo, que le imprimían carácter a todas sus actuaciones en el ejercicio médico y que habían modelado, durante los años de generosa dedicación a sus pacientes, esa personalidad de quien no debió hacer el menor esfuerzo para inspirar confianza, en todos los que nos acercamos a él, bien se tratara de discípulos ávidos de saber, de comprofesores interesados en sus opiniones, de enfermos necesitados de sus extensos conocimientos y práctica, o de amigos y familiares que encontrábamos en él, todos, siempre, una respuesta cálida e inmensamente tranquilizadora, respaldada por una sonrisa que se extendía, como por encanto, a la expresión generosa de su rostro y nos introducía a la confianza del amigo o, en forma más profunda, al imperecedero afecto que despertaba en sus seres queridos.

  2. The spaniards conflict at the process of emancipation: Rio de La Plata and Mexico cases at the beginning of the 19th century

    Directory of Open Access Journals (Sweden)

    María Graciela León Matamoros

    2010-11-01

    Full Text Available The wars of independence in Latin America and the consequent process of building the nation accounted for the Spaniards unsteadiness, reflected, in various degrees of intensity, in emerging countries. The intent of this paper is to present the measures that the governments of two different territories such as Mexico and Río de la Plata, adopted against the Spaniards for legitimacy. The position of both governments reveal the relationships and affronts which every country kept to their former conquerors, and the levels of dependence on the Iberian that made inoperable, in many cases, the intention of decrease their privileges. Therefore the aim is to show the history, the parallels and differences that these countries had in their provisions against the Spaniards.

  3. Evaluation of zoobenthic assemblages and recovery following petroleum spill in a coastal area of Rio de la Plata estuarine system, South America

    International Nuclear Information System (INIS)

    Ocon, C.S.; Capitulo, A. Rodrigues; Paggi, A.C.

    2008-01-01

    The objective of this work was to analyse zoobenthic assemblages in the coastal sector of the Rio de La Plata, Argentina, after a petroleum spill. Sampling stations were located in representative sites of various landscapes. Structure, composition, physico-chemical parameters and seasonal changes were recorded in order to assess taxocenosis evolution during the period 1999-2003. Recovery signs were estimated by means of biotic indices and the presence of sensitive species. Tolerant species were dominant in heavily polluted sites, with low diversity and water quality values, according to the biotic indices used. In certain zones, sediment quality remains impoverished, with a visible oil film on the surface. However, during the last sampling, some points showed an increase in biotic indices, pointing to a slight improvement in environmental conditions. - Oil spill impact was evaluated by zoobenthos response in an estuarine system

  4. El escudo alegórico de la Universidad Nacional de La Plata : Análisis iconológico de un símbolo centenario

    OpenAIRE

    Passarella, Luciano

    2012-01-01

    La Universidad Nacional de La Plata, cuenta desde su fundación con un escudo que la representa. A más de cien años de su generación sigue siendo hoy el símbolo más importante de su identidad, formando parte de la marca vigente actualmente. Dicho escudo posee una construcción singular y se enmarca en lo que dentro del universo de signos de universidades constituyen los escudos alegóricos utilizados como marcas. En el presente trabajo se parte de la idea de que en cada época o período histór...

  5. INVESTIGACIÓN DE FIBRAS DE POLIPROPILENO ADITIVADAS CON NANOPARTÍCULAS DE PLATA PARA LA MEJORA DE PROPIEDADES BIOACTIVAS EN EL SECTOR TEXTIL

    OpenAIRE

    FAGES SANTANA, EDUARDO

    2013-01-01

    El presente y el futuro de la industria textil están íntimamente ligados al concepto de textil técnico, artículos éstos concebidos para su aplicación en diferentes segmentos de mercado: salud y ámbito hospitalario, industria naval, aeronáutica y de automoción, sector de construcción e ingeniería civil, defensa e industria militar, etc. En el presente proyecto de investigación se ha contemplado la funcionalización de fibras de polipropileno mediante la aditivación de nanopartículas de plata. D...

  6. Copper, lead and zinc distribution in soils and sediments of the South-Western coast of the Rio de la Plata Estuary

    Energy Technology Data Exchange (ETDEWEB)

    Camilion, M.C.; Hurtado, M.A. [CISAUA-UNLP: Centro de Investigaciones de Suelos y Aguas de Uso Agropecuario, Facultad de Ciencias Naturales y Museo, Univ. Nacional de La Plata, La Plata (Argentina); Manassero, M.J. [CIG-UNLP-CONICET: Centro de Investigaciones Geologicas, Facultad de Ciencias Naturales y Museo, Univ. Nacional de La Plata, La Plata (Argentina); Ronco, A.E. [CIMA-UNLP-CONICET: Centro de Investigaciones del Medio Ambiente, Facultad de Ciencias Exactas, Univ. Nacional de La Plata, La Plata (Argentina)

    2003-07-01

    The compositional study of suspended matter in water from rivers of different latitudes and climates has revealed that the fine fraction reflects both substrate lithology from source areas or topsoil composition along the course. Metal distribution patterns are also strongly related to the clay mineral fate in fluvial aquatic systems. For the particular case of the coastal area of the Rio de la Plata estuary in South America, previous studies have, on the one hand, focused on the analysis of distribution patterns of heavy metals in bottom river sediments and, on the other hand, on the assessment of metal contents in topsoils. The present study was conducted to evaluate the Cu, Pb and Zn distribution in soils and sediments from four drainage basins crossing two differentiated geomorphologic units composed of unconsolidated materials and to understand the metal behaviour. (orig.)

  7. Sewage impact on the composition and distribution of Polychaeta associated to intertidal mussel beds of the Mar del Plata rocky shore, Argentina

    Directory of Open Access Journals (Sweden)

    Elías Rodolfo

    2003-01-01

    Full Text Available The polychaete composition and distribution within mussel beds were studied in order to assess organic pollution due to domestic sewage in a rocky shore of Mar del Plata (Argentina during 1997. Four stations and a control site were randomly sampled around the local effluent. Quantitative data on polychaetes, as well as sediment accumulated among mussels and its organic carbon content were measured. Polychaete distribution patterns are related to the organic matter gradient, being Capitella cf. capitata, Neanthes succinea (Frey & Leuckart, 1847 and Boccardia polybranchia (Haswell, 1885 the dominant indicator species close to the effluent. At medial distances, the cirratulids Caulleriella alata (Southern, 1914 and Cirratulus cirratus (Müller, 1776 are very important in abundance. The syllids Syllis prolixa Ehlers, 1901 and S. gracilis Grube, 1840 are distributed along the study area, but dominate at the medial stations and at the control site. The orbiniid Protoariciella uncinata Hartmann-Schröder, 1962 is subdominant at the control station.

  8. On the path of plumes of the Río De La Plata Estuary main tributaries and their mixing scales

    Directory of Open Access Journals (Sweden)

    Claudia G Simionato

    2009-12-01

    Full Text Available With a length of 300 km and a width that narrows from 220 km at its mouth to 40 km at its upper end, the Río de la Plata is one of the largest estuaries of the world. Its three main tributaries -contributing to a total mean runoff of 22,000 m³ s-1- have different properties and are object of diverse environmental impact due to dissimilar development conditions on their shores. The knowledge of the paths of the plumes of those tributaries along the estuary and their mixing scales is necessary for management purposes. In this paper, advection-diffusion equations for passive tracers are coupled to the three-dimensional Hamburg Shelf Ocean Model and validated by means of a case study. Then, simulations in which each tributary is characterized by a different dye tracer are done for scenarios resulting of the combination of diverse characteristic atmospheric forcing and runoff conditions. The impact of bathymetry and Earth's rotation on plumes paths and mixing is also evaluated. Results indicate that, for mean to low discharge conditions, the path of the waters of the tributaries is in the form of two main plumes. The different water speeds of both tributaries, the presence of a bend immediately after their confluence and the varying geometry and bathymetry of the estuary favor a rapid mixing between the Uruguay and Paraná Guazú-Bravo waters, which then flow along the northern portion of the upper estuary channel. The Paraná de las Palmas waters, instead, occupy the southern shallow region of Playa Honda in the upper estuary and then flow following the southern coast. Downstream Colonia, at the intermediate estuary, the occurrence of another large bend and a change in bathymetric features force the flow to concentrate in the central part of the estuary and favor further mixing between the plumes. For high discharge conditions the northern part of the upper estuary is divided into two regions, one with a larger concentration of Uruguay waters

  9. Caracterización del estado nutricional, enteroparasitosis y condiciones socio-ambientales de la población infanto-juvenil del partido de La Plata

    Directory of Open Access Journals (Sweden)

    Oyhenart, Evelia Edith

    2013-12-01

    Full Text Available En el presente trabajo se caracterizaron el estado nutricional, las enteroparasitosis y las condiciones socio-ambientales de niños residentes en el Casco urbano y 11 localidades del Partido de La Plata, provincia de Buenos Aires, mediante un estudio transversal. Se midieron peso y talla de 6.397 niños entre 4.0 y 13.9 años. Se calculó el índice de masa corporal y se estimó el estado nutricional utilizando NHANES III. Las variables socio-ambientales se relevaron mediante encuesta estructurada. El análisis parasitológico se realizó en 729 niños sobre muestras seriadas de materia fecal analizadas mediante la técnica de Ritchie y escobillado anal. Los resultados globales indicaron: 22.1% de exceso de peso, 8.7% de desnutrición y 68.5% de parasitosis, siendo más prevalentes Enterobius vermicularis (38.7%, Blastocystis hominis (36.1%, Giardia lamblia (19.1% y protozoos comensales (26.1%. Los geohelmintos tuvieron valores inferiores (9.3%. El partido de La Plata presenta gran heterogeneidad en el estado nutricional y las infecciones parasitarias de los niños por cuanto resultan dependientes de las características socio-ambientales. Las deficientes condiciones ambientales, el bajo nivel educativo y la falta de trabajo formal de los padres explicarían la coexistencia de parasitosis y desnutrición infantil, prevaleciendo la de tipo crónico. Por otra parte, las localidades en las que hay menor grado de cobertura de servicios urbanos básicos, pero los padres poseen mayor nivel educativo y trabajo formalizado, presentan prevalencias más elevadas de exceso de peso.

  10. A trans-ecosystem fishery: Environmental effects on the small-scale gillnet fishery along the Río de la Plata boundary

    Science.gov (United States)

    Jaureguizar, Andrés Javier; Cortés, Federico; Milessi, Andrés Conrado; Cozzolino, Ezequiel; Allega, Lucrecia

    2015-12-01

    To improve the understanding of the environmental processes affecting small-scale gillnet fisheries along neighboring waters of estuaries, we analyzed the main climatic forcing and the environmental conditions, the fishery landing spatial and temporal variation, including the relative importance of site, distance to coast, temperature and salinity in the structuring of landed species profile. Data were collected monthly in two sites along the adjacent south coast of the Río de la Plata between October 2009 and September 2010. The gillnet fishery was dominated by four species (Cynoscion guatucupa, Micropogonias furnieri, Mustelus schmitti and Parona signata) from a total of 38 species landed, which accounted for 98.6% of total landings. The fishing effort and landings by the fishery were largely conditioned by the availability of fish species in the fishing grounds resulting from the combination of the species reproductive behavior and the predominant environmental conditions. The highest abundances for some species occurred before (M. furnieri, C. guatucupa, P. signata) or during the reproductive period (M. schmitti, Squatina guggenheim), while in other species it was associated with favorable environmental conditions during cold months (Squalus acanthias, Callorhinchus callorhynchus, Galeorhinus galeus) or warm months (Trichiurus lepturus). The predominant seasonal environmental conditions along the coast were mainly determined by the location of Río de la Plata boundary, whose spatial extent was forced by the wind patterns and freshwater discharge. The strong environmental dependence means that the small-scale fishery is in fact a seasonal trans-ecosystem fishery. This attribute, together that shared the resources with the industrial fishery and the overlap of the fishery ground with essential habitat of sharks, make this kind of small-scale gillnet fishery particularly relevant to be included in the development of a coastal ecosystem-based management approach.

  11. Identification of palaeo-seawater intrusion in groundwater using minor ions in a semi-confined aquifer of the Río de la Plata littoral (Argentina)

    International Nuclear Information System (INIS)

    Santucci, L.; Carol, E.; Kruse, E.

    2016-01-01

    The hydrochemistry of minor elements and traces such as bromide, lithium, strontium, uranium and selenium, together with the chemical analysis of major ions, has been used in the study of salinization process. This process occurs in a semi-confined aquifer that corresponds to a Pliocene–Pleistocene fluvial environment. The semi-confined aquifer is located in the littoral of the cities of Ensenada and Berisso, in the region of the middle Río de la Plata estuary, Argentina. Groundwater salinization was detected in the semi-confined aquifer in the coastal plain area, with salt contents that increase from the loess plain towards the river. The content of major ions that predominate in sea water (Cl"−, Na"+ and Mg"2"+), as well as the Cl"−/Br"− and U vs. Cl"− ratios, demonstrates that such salinization is related to sea water, which shows no correspondence with estuary water. In the salinized area, Li, Sr and Se enrichments occur, and are used as tracers of the average time that a substance remains in solution in sea water in the aquifer. The study of such minor ions together with the geological evolution of the area made it possible to recognize that the salt water in the semi-confined aquifer corresponds to a palaeo-intrusion of sea water associated with the Pleistocene–Holocene ingressions caused by the climate changes occurring during the Quaternary. - Highlights: • The semi-confined aquifer in a sector of the Río de la Plata estuary is salinized. • Saline content is higher in the aquifer than in the estuary. • Minor elements indicate the occurrence of palaeo-seawater intrusion. • Palaeo-seawater intrusion may be associated with interglacial fluctuations.

  12. Environmental modulation of the plankton community composition and size-structure along the eutrophic intertidal coast of the Río de la Plata estuary, Argentina

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    Maximiliano D. Garcia

    2014-05-01

    Full Text Available In this study we investigated the spatial distribution of the plankton community, bacterio-, phyto- and zooplankton, in relation with environmental conditions along the intertidal coast of the Río de la Plata estuary, Argentina. Plankton was analyzed in terms of species composition, abundance, biomass (carbon content and size-structure. We aim to evaluate the potential effects of anthropogenic impacts (e.g., nutrient enrichment and physicochemical gradients alongshore (e.g., salinity, turbidity on the composition and functioning of the plankton. We asked whether the natural structuring of the plankton by salinity and turbidity, known to be true of estuaries, is modified by eutrophication along the studied shoreline. We found that the density and biomass of bacteria and phytoplankton were strikingly enhanced by high eutrophication levels along the intertidal southwest coast of the Río de la Plata estuary. We also found that the highest zooplankton density in the most polluted area but the biomass showed a different distribution pattern. Nevertheless, when zooplankton was analyzed by means of its size fraction, we accordingly found that the microzooplankton biomass was positively associated with smaller-size phytoplankton groups and the most polluted study sites. Copepods were the major taxonomic groups that best represented the mesozooplankton biomass. We therefore expected that its distribution was modulated by the presence of its food items (i.e., large cells which, in turn, were more abundant in the middle-outer zone. In contrast, we found that the highest biomass of copepods occurred at the innermost site of the estuary and we found no significant association with other planktonic groups. Overall, this study highlights the noteworthy impacts of human activities modifying the functioning of this coastal ecosystem. The differences found in the taxonomic composition and size structure of the planktonic community assemblage between the most

  13. Identification of palaeo-seawater intrusion in groundwater using minor ions in a semi-confined aquifer of the Río de la Plata littoral (Argentina)

    Energy Technology Data Exchange (ETDEWEB)

    Santucci, L., E-mail: eleocarol@fcnym.unlp.edu.ar [Centro de Investigaciones Geológicas (CIG), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad Nacional de La Plata - UNLP, Calle 64 y Diag. 113, 1900 La Plata, Buenos Aires (Argentina); Carol, E. [Centro de Investigaciones Geológicas (CIG), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Universidad Nacional de La Plata - UNLP, Calle 64 y Diag. 113, 1900 La Plata, Buenos Aires (Argentina); Kruse, E. [Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Cátedra de Hidrología General de la Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata (UNLP), Calle 64 #3, 1900 La Plata, Buenos Aires (Argentina)

    2016-10-01

    The hydrochemistry of minor elements and traces such as bromide, lithium, strontium, uranium and selenium, together with the chemical analysis of major ions, has been used in the study of salinization process. This process occurs in a semi-confined aquifer that corresponds to a Pliocene–Pleistocene fluvial environment. The semi-confined aquifer is located in the littoral of the cities of Ensenada and Berisso, in the region of the middle Río de la Plata estuary, Argentina. Groundwater salinization was detected in the semi-confined aquifer in the coastal plain area, with salt contents that increase from the loess plain towards the river. The content of major ions that predominate in sea water (Cl{sup −}, Na{sup +} and Mg{sup 2+}), as well as the Cl{sup −}/Br{sup −} and U vs. Cl{sup −} ratios, demonstrates that such salinization is related to sea water, which shows no correspondence with estuary water. In the salinized area, Li, Sr and Se enrichments occur, and are used as tracers of the average time that a substance remains in solution in sea water in the aquifer. The study of such minor ions together with the geological evolution of the area made it possible to recognize that the salt water in the semi-confined aquifer corresponds to a palaeo-intrusion of sea water associated with the Pleistocene–Holocene ingressions caused by the climate changes occurring during the Quaternary. - Highlights: • The semi-confined aquifer in a sector of the Río de la Plata estuary is salinized. • Saline content is higher in the aquifer than in the estuary. • Minor elements indicate the occurrence of palaeo-seawater intrusion. • Palaeo-seawater intrusion may be associated with interglacial fluctuations.

  14. Individual memory and collective nostalgia in Uruguay: the fragmentation of time in the short framed stories of Tijeras de Plata by Hugo Burel

    Directory of Open Access Journals (Sweden)

    Giuseppe Gatti

    2012-12-01

    Full Text Available The present study analyzes the role of the process of memory recovery in the Uruguayan contemporary literary space. The article focuses on the dynamics of recovery of the past in the work of the Montevidean Hugo Burel (born in 1951, especially in his novel Tijeras de Plata (2003. The first part of our study analyses how the novel describes – in a symbolic form – the geo-social changes that have characterised the Uruguayan space from the second half of the 20th century (decentralization of urban population; gradual decline in the social, cultural and economic structure of many central neighbourhoods. We examine the narrative forms used by Burel (short stories within a frame in the light of these phenomena, and consider in turn another type of fragmentation, of an extra-literary nature:  investigating nature of the relationship between literature and the idiosyncrasy of Uruguayan social world: we refer to a frequent sensation of “fracture with the past” that envelops Uruguayan society. In the second part of the article we demonstrate why Tijeras de Plata can be considered as a “literary tool” to recover a missing past: the novel develops as a “story of past memories”, focusing on the process of impoverishment that affects many urban zones of Montevideo. On the other hand, the double operation of rescue (first the restoration of the individual memories related to the neighbourhood, then the revival of the prosperity once banished from the city suggests an evocation of a past of happiness and can be considered as literary means of rescuing that old world form oblivion. In conclusion, it is possible to read the novel as a metaphorical reflection on the decline of a “lost country”.

  15. El premio de la plata y la devaluación del vellón en Guipúzcoa en el siglo XVII

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    Álvaro Aragón Ruano

    2001-01-01

    Full Text Available El presente artículo analiza la evolución del premio de la plata durante el siglo xvii en Guipúzcoa, donde aparecen dos modelos de comportamiento, siempre en relación con la abundancia y movimiento de la plata, que es el principal factor que explica las variaciones del premio. Se constata, no obstante, que en cada localidad los premios son diferentes, lo que demuestra la autonomía de las economías locales de Antiguo Régimen. Así mismo, hay que decir que las mayores repercusiones de este fenómeno se dejaron sentir en los mercados y en las transacciones locales, afectando principalmente a los consumidores. De todas formas, se demuestra la necesidad de seguir realizando investigaciones en los diferentes territorios que formaban la Corona, y desterrar definitivamente la generalización de datos como los de Hamilton.The next article analises the evolution of the silver's prize during the XVIIth Century in Guipúzcoa, where there arise two trends of behaviour, always related to the movement and abundance of the silver, which are the main factors that explain the changes of the prize. It is verified, nevertheless, that in each town the prizes are different, which shows the local economies' autonomy in the Ancient Regime. Besides, we should add that the main repercussion of this phenomenon was reflected in the local markets and transactions, mainly affecting the communities. In any case, it is stated the need to continué investigating in the different territories which formed the Crown, and to stamp out definetely the generalization of data, such as Hamilton's one.

  16. Los residuos sólidos urbanos en Mar del Plata, Argentina ¿problemática ambiental o insumos para la industria?

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    Mariana Gonzalez Insua

    2015-03-01

    Full Text Available A partir de Conferencia de Naciones Unidas sobre Medio Ambiente y Desarrollo (CNUMAD-92 se establecen las bases para un manejo integral de los Residuos Sólidos como parte del Desarrollo Sostenible; en este contexto Argentina desarrolla la Estrategia Nacional de Gestión de Residuos Sólidos Urbanos (ENGIRSU en el año 2005. Una de las estrategias para el  estudio de los residuos como materiales posibles de ser valorizados, es el análisis de la cadena de valor. El presente trabajo tiene por objetivos contribuir al conocimiento de la Gestión Integral de los Residuos Sólidos Urbanos de la ciudad de Mar del Plata y analizar la revalorización de los mismos en el Circuito Formal (CF de recuperación bajo el enfoque de Cadena de Valor, visualizando a sus principales actores y su poder y control dentro de la cadena. Para alcanzarlos se realiza un revisión histórico-ambiental de la problemática de los residuos en Argentina hasta el desarrollo de ENGIRSU; puntualizando el análisis en la implementación de la estrategia en la ciudad de Mar del Plata focalizada en la etapa de  separación de residuos, específicamente en la Planta de Separación y Clasificación operada por la Cooperativa CURA. Como resultado se evidencia una baja productividad de la planta como componente de GIRSU y un rol débil como eslabón dentro la cadena de valor de residuos sólidos urbanos.

  17. Oribátidos arborícolas del «Paseo del Bosque» (La Plata, provincia de Buenos Aires, Argentina Canopy soil suspendend oribatids from the «Paseo del Bosque» (La Plata, province of Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Ana Salazar Martínez

    2007-07-01

    Full Text Available En esta nota se aporta información sobre los oribátidos arborícolas del Paseo del Bosque, La Plata, Argentina (34º 54' S, 57º 55' W, a partir de muestreos realizados en suelos suspendidos con distinta concentración de detritos. La fauna de oribátidos estuvo representada por 17 especies, siendo Cultroribula sp., Pheroliodes cf. minutus Baranek, Rhysotritia peruensis Hammer y Oppiella nova Oudemans las de mayor importancia relativa. De las especies registradas, 76 % son propias del ambiente arborícola.This work deals with the arboreal oribatids of «Paseo del Bosque», La Plata, Argentina (34º 54' S, 57º 55' W. Samples were taken from suspended soils exhibiting unequal detritus concentrations. The overall sample included 17 oribatid species, exhibiting Cultroribula sp., Pheroliodes cf. minutus Baranek, Rhysotritia peruensis Hammer and Oppiella nova Oudemans the highest relative importance. Seventy percent of the recorded species are representative of the arboricole environment.

  18. Seasonal fluctuations in prevalence of dog intestinal parasites in public squares of Mar del Plata city, Argentina and its risk for humans Estacionalidad en la prevalencia de parásitos intestinales caninos en plazas públicas de Mar del Plata, Argentina, y su riesgo para la salud humana

    Directory of Open Access Journals (Sweden)

    V. Andresiuk

    2007-12-01

    Full Text Available The aim of this work is to analyze whether there is a seasonal prevalence of parasites in dog feces from public squares in Mar del Plata city, Argentina, and to evaluate the climatic conditions that promote the development of parasites and allow the transmission to people. The study was performed in 21 squares from June 2001 to May 2002. Samples were processed by the Willis technique. Differences in prevalence of parasites were examined for significance by the Chisquare test. Climatic data were obtained from the Library of the National Meteorological Service of Argentina. Total parasitic prevalence was higher in winter than in summer. The prevalence of Ancylostoma spp. was higher in the summer-autumn period. For Toxocara canis, the prevalence was higher in winter whereas for Trichuris vulpis, it was higher in winter, spring and summer. This work shows high prevalence of total parasites throughout the year. For Ancylostoma spp., summer and autumn might be the seasons with higher sanitary risk. On the other hand, T. canis could present the higher risk to people in winter and, T. vulpis, would be transmitted throughout the whole year. The seasonal variation in prevalence of dog parasites results in continuous exposure to people visiting the squares, not only Mar del Plata residents but also tourists from other regions of Argentina and the world, with at least one species of parasite with sanitary risk.El objetivo de este trabajo es analizar la variación estacional de la prevalencia de los parásitos presentes en las heces caninas halladas en plazas públicas de la ciudad de Mar del Plata y evaluar aquellas condiciones climáticas que promueven su desarrollo y permiten su transmisión a la gente. El estudio se realizó en 21 plazas desde junio de 2001 hasta mayo de 2002. Las muestras fueron procesadas con la técnica de Willis. Se utilizó el test de c² para comparar la prevalencia de los diferentes parásitos. Los datos climáticos fueron

  19. Sensor óptico colorimétrico de peróxido de hidrógeno con doble referencia basado en nanopartículas de oro y plata

    OpenAIRE

    Ibáñez Puy, Elia

    2016-01-01

    Este trabajo se centra en la síntesis en vía húmeda para la obtención de nanopartículas estables y con una morfología controlada. Se trabaja con nanopartículas de oro y plata de forma esferoidal, y se realiza un estudio exhaustivo de múltiples factores como la concentración y el pH, para seleccionar el mejor agente encapsulante con el objetivo de obtener un sensor colorimétrico basado en la estabilidad del oro frente a la reactividad de la plata ante el contacto con peróxido de hidrógeno G...

  20. Establishment of a non-governmental regional approach to La Plata River Basin integrated watershed management promoted throughout three international workshops supported by UN and Japanese agencies, led by ILEC

    Science.gov (United States)

    Calcagno, Alberto; Yamashiki, Yosuke; Mugetti, Ana

    2002-08-01

    The La Plata River Basin is one of the largest international river basins in the world, with an area of about 3 million km2. It spreads across five countries (Argentina, Bolivia, Brazil, Paraguay and Uruguay), and its water resources are essential for their economic development. Together with reservoir development, extensive deforestation, intensive agriculture practices and large urban developments took place in the Paraná, Paraguay and Uruguay basins, affecting environmental conditions and raising important issues concerning water resources use and conservation. Therefore, the need to promote participatory and cooperative efforts among water resources stakeholders, as well as the systematic exchange of information and experiences on common regional problems among organizations and experts from throughout the basin who are devoted to water resources use and management, was reported by researchers and managers gathered at the First and Second International Workshops on Regional Approaches for Reservoir Development and Management in the La Plata River Basin (held in 1991 and 1994). As a concrete response to this need, the efforts of a number of organizations from various countries within the basin, with the support of international and national governmental organizations, resulted in the foundation of La Plata River Basin Environmental Research and Management Network (RIGA) in March 2001. This was within the framework of the Third International Workshop, which was precisely one of the short-term activities included in the RIGA Action Plan. During the preparatory processes for the RIGA Network, the presence of Japanese cooperation supporting the La Plata River Basin Workshops through a non-governmental international organization (ILEC) played an important role in stimulating such an organization-based joint approach in the basin. This outcome, although not originally planned, constituted a welcomed byproduct of its main specific interest in the region, which was the

  1. Influencia de la temperatura en la fijación y penetración de la plata durante la lixiviación de calcopirita con microorganismos termófilos moderados

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    Cancho, L.

    2004-06-01

    Full Text Available Bioleaching of chalcopyrite using mesophilic microorganisms considerably improves in the presence of silver. However, the studies carried out with moderate thermophilic microorganisms do not show a significant improvement with regard to the use of mesophilic bacteria. The main objective of the present work has been to study the silver fixation on chalcopyrite at 35 and 45 °C and its influence on the microbiological attack. Different observations using SEM, EDS microanalysis and concentration profiles using electron microprobe have been carried out. The study of the different samples showed that silver fixation was more favourable at 35 °C than at 45 °C. In addition, bacterial action improved silver penetration through attack cracks.

    La biolixiviación de la calcopirita con microorganismos mesófilos mejora considerablemente cuando se utiliza plata en el medio de reacción. Sin embargo, los estudios realizados con microorganismos termófilos moderados no muestran una mejora significativa con respecto a la utilización de bacterias mesófilas. El objetivo del presente trabajo ha sido el estudio de la fijación de plata sobre calcopirita a 35 y 45 °C y su influencia en el ataque microbiológico. Se han realizado observaciones con SEM, microanálisis por EDS y perfiles de concentración con microsonda electrónica. El estudio de las distintas muestras reveló que la fijación de la plata fue más favorable a 35 que a 45 °C y que la acción bacteriana favoreció la penetración de la plata a través de las grietas de ataque.

  2. Synthesis and electrochemical characterization of palladium-based cathode catalysts, resistant to the presence of methanol; Sintesis y caracterizacion electroquimica de catalizadores catodicos base paladio, resistentes a la presencia de metanol

    Energy Technology Data Exchange (ETDEWEB)

    Salvador, Jose J. [Centro de Investigacion y de Estudios Avanzados del IPN, Mexico D.F. (Mexico)] e-mail: jsalvador@cinvestav.mx; Collins, Virginia H. [Centro de Investigacion en Materiales Avanzados, Chihuahua, Chihuahua (Mexico); Solorza Feria, Omar [Centro de Investigacion y de Estudios Avanzados del IPN, Mexico D.F. (Mexico)

    2009-09-15

    This work presents the synthesis and characterization of palladium-based electrocatalysts (PdSn and PdPtSn) prepared with the salt-reduction method for oxygen reduction reaction (ORR). The compounds obtained are characterized by sweep electron microscopy, electron transmission microscopy and x-ray diffraction of powder. The electrocatalysts obtained had particle sizes less than 10 nm. The evaluation of the catalytic activity of the catalysts was performed using cyclic voltametry and rotating disc electrode. These experiments were conducted in an H{sub 2}SO{sub 4} 0.5 M solution with different methanol concentrations. The presence of methanol improved the catalytic activity of PdSn, but did not show any effect on the PdPtSn alloy. The performance of the DMFC mono cell using PdPtSn as a cathode showed a potential of 10 mW cm{sup -2} at 50 degrees Celsius. [Spanish] En este trabajo se presenta la sintesis y caracterizacion de electrocatalizadores de base Paladio (PdSn y PdPtSn) preparados mediante el metodo de reduccion de sales, para la reaccion de reduccion de oxigeno (RRO). Los compuestos obtenidos se caracterizaron por microscopia electronica de barrido, microscopia electronica de transmision y difraccion de rayos X de polvos. Los electrocatalizadores obtenidos presentaron un tamano de particula menores a 10 nm. La evaluacion de la actividad catalitica de los catalizadores se llevo a cabo mediante voltametria Ciclica y electrodo de disco rotatorio, estos experimentos fueron realizados en una solucion de H{sub 2}SO{sub 4} 0.5 M con diferentes concentraciones de metanol. La presencia de metanol mejoro la actividad catalitica de PdSn, pero no mostro ningun efecto sobre la aleacion PdPtSn. El desempeno de la monocelda de DMFC usando como catodo PdPtSn, mostro una potencia de 10 mW cm{sup -2} a 50 grados centigrados.

  3. Detrital zircons from samples of five Neo proterozoic sandstone units deposited on Uruguay and Argentina: about evolution of paleographic Rio de la Plata craton

    International Nuclear Information System (INIS)

    Gaucher, C.; Poire, D.G.; Pamoukaghlian, K.; Gomez Peral, L.; Finney, S.; Valencia, V.; Blanco, G.

    2007-01-01

    We report U-Pb ages of detrital zircons from samples of five Neoproterozoic sandstone units deposited on the Rio de la Plata Craton (RPC) in Uruguay and Argentina. Quartz-arenites of the Piedras de Afilar Formation show typical Transamazonian ages, with peaks at 2.00-2.07, 1.87 and 1.78 Ga. However, the most important zircon population is Mesoproterozoic, showing maxima at 1.49, 1.35, 1.25 and 1.0 Ga. Zircons recovered from two sandstone levels in the Arroyo del Soldado Group (Yerbal and Cerros San Francisco formations) are mostly Archean in age, with maxima at 3.2 and 2.7 Ga. Palaeoproterozoic zircons are also prominent in this unit, with peaks at 2.45 and 2.18, with the latter a typical Transamazonian age. Two samples from the Sierras Bayas Group in Tandilia (Argentina) show different age spectra. Sandstones of the Villa Monica Formation show a unimodal zircon population of Transamazonian age (peak at 2.13 Ga). Sandstones of the Cerro Largo Formation are characterized by a dominant Transamazonian zircon population (peaks at 2.15, 2.0 and 1.79), but also important Archean-lowermost Palaeoproterozoic (3.33, 2.99, 2.7, 2.47 Ga) and Mesoproterozoic peaks (1.55, 1.23 and 1.06). The abundance of Mesoproterozoic detrital zircons is surprising. A proto-Andean, Mesoproterozoic belt is suggested as the source of the Mesoproterozoic detritus. Archean rocks of the RPC crop out only in the Nico Perez Terrane in Uruguay, suggesting that the Nico Perez Terrane was much closer to Tandilia than it is today. The sinistral reactivation of the Sarandi del Yi Shear Zone in the Cambrian, as a result of tangential collision of the Cuchilla Dionisio-Pelotas Terrane, may explain this observations. The absence of Neoproterozoic zircons shows that the studied units were deposited in a stable continental margin opening to the East and South. These Neoproterozoic basins had obviously no contribution whatsoever from Brasiliano-Pan African belts, supporting the idea of Cambrian terrane

  4. Contribución a la identificación de esporas del Reino Fungi en la atmósfera de La Plata, Argentina

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    Daniela S. Nitiu

    2010-12-01

    Full Text Available A partir del análisis del registro aeromicológico de la ciudad de La Plata se propone la definición de Grupos Morfológicos de esporas del Reino Fungi. Este estudio constituye un aporte metodológico a la identificación y recuento de una fracción de la micobiota atmosférica. Para la definición de los grupos, se han tenido en cuenta los criterios de Saccardo (1886 y reformulado los agrupamientos de Díaz et al. (1998 y Aira et al. (2005. Se han creando 4 nuevos grupos y se han incorporando otros tipos esporales a las clasificaciones previas. Cada grupo, incluye entre 2 y 6 tipos de esporas pertenecientes a los Phylum Zygomycota, Basidiomycota y Ascomycota y sus anamorfos, que han sido asignados a nivel genérico. Los caracteres que definen dichas asociaciones son: Grupo Absidia, amerosporas hialinas; Grupo Cortinarius, amerosporas pigmentadas amigdaliformes; Grupo Didymella, didimosporas hialinas o levemente coloreadas; Grupo Didymosphaeria, didimosporas y didimoconidios pigmentados; Grupo Lepthosphaeria, fragmosporas septadas hialinas a pigmentadas y Grupo Helminthosporium, fragmosporas distoseptadas hialinas a pigmentadas. Esta investigación aspira a proporcionar una herramienta que facilite el procesamiento de datos y aporte nuevos elementos cualitativos a las clasificaciones previas, contribuyendo en la compleja problemática de identificación de las esporas fúngicas.Based on the aeromycological analysis of La Plata city, artificial Morphological Groups of fungal spores were defined. This study is a methodological contribution to the identification and counting of a fraction of the atmospheric micobiota. For the definition of groups, the criteria of Saccardo (1886 were taken into account and the groupings created by Díaz et al. (1998 and Aira et al. (2005 have been reformulated. Four new groups have been created and other sporal types have been incorporated to previous classifications. Each of them includes 2 to 6 spore types

  5. Orden y ambigüedad en la formación territorial de Río de la Plata a fines del siglo XVIII

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    Guillermo Wilde

    2003-07-01

    Full Text Available Por mucho tiempo la heterogénea población que habitaba la región Río de la Plata, en las fronteras entre España y Portugal, hacia fines del siglo XVIII fue asociada con la barbarie. Con el fin de homogeneizar a esta población y ajustar su comportamiento a las leyes indianas, la monarquía española implementó varias políticas de control. Sin embargo, en el corto plazo estas políticas no lograron modificar las prácticas económicas, políticas y simbólicas de esta población ni su débil percepción del Estado. Por el contrario, los actores locales mantuvieron sus dinámicas relativamente autónomas hasta casi la mitad del siglo XIX. Este artículo analiza la contradicción entre las representaciones del Estado sobre esos actores locales, construidos como "alteridad", y las dinámicas concretas que los caracterizaban, sus percepciones del territorio y el Estado, y sus estrategias para evadir los controles de las autoridades oficiales.For a long time, the heterogenous population that inhabited the Río de la Plata Region, in the borderlands of Spain and Portugal, toward the end of 18th Century, was associated to barbarism. To make that population homogenous and to adjust its behavior to indigenous Law, the Spanish Monarchy carried out several policies of control. However, in a short term these policies were neither able to modify the economic, political and symbolic practices of that population, nor were they able to weaken the perception this population had of the State. On the contrary, local actors kept their own dynamics until almost the first half of the 19th Century. This paper analyses the contradiction between State representations of local actors and the concrete dynamics that characterized them, their perceptions of territory and State, and their strategies for avoiding control by official authorities.

  6. Estudio de la climatología y la hidrología de la Cuenca del Plata en un conjunto de modelos climáticos globales Study of the La Plata Basin climatology and hydrology in a set of global climate models

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    Ramiro Saurral

    2009-06-01

    Full Text Available La Cuenca del Plata provee de agua potable a millones de personas a través de cinco países en Sudamérica. En el contexto de un potencial cambio futuro en las condiciones medias del clima, los caudales de los ríos de la cuenca podrían verse afectados y en este sentido es de sumo interés poder inferir estos posibles cambios en los caudales para década venideras. El objetivo de este trabajo es determinar la habilidad de tres modelos climáticos globales (CNRM-CM3, ECHAM5-MPI/OM y GFDL-CM2.0 en simular los caudales observados de los principales ríos de la Cuenca del Plata. Para ello, se emplearon las salidas de precipitación y temperatura de esos modelos climáticos para forzar un modelo hidrológico distribuido durante la última década del siglo XX (1990- 1999. Los resultados muestran que los tres modelos presentan serias deficiencias en la representación del ciclo hidrológico y que esas diferencias están principalmente explicadas por los importantes errores que tienen en los patrones de precipitación y temperatura sobre el sur de Sudamérica. Esto determina un fuerte impedimento al potencial uso que se podría dar a estos modelos para inferir posibles cambios futuros en los caudales de los ríos de la región.Hydrological modeling is a potent tool that can be useful to, among other things, determine the potential future availability of fresh water on Earth. In particular, the La Plata Basin supplies fresh water to millions of people across five countries. In a context of possible future changes on climate, river streamflows could be affected and in this sense it is of crucial importance to infer these potential changes for the upcoming decades. The objective of this paper is to determine the ability of three climate models (CNRM-CM3, ECHAM5-MPI/OM and GFDL-CM2.0 to simulate the observed discharges of the main La Plata Basin rivers. To force the distributed hydrology model, climate models output data included daily minimum and

  7. Financiamiento y comercialización de la agricultura familiar en el Gran La Plata. Estudio en el marco de un proyecto de Desarrollo Territorial Financing and commercialization of family farming in Gran La Plata. Study as part of a Territorial Development project

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    Ramón I. Cieza

    2012-01-01

    Full Text Available Currently, family farming has taken visibility both in academic works and in the design of public policies. Even though are recognized own characteristics which differentiate it from the business production, they are presented according to the type of production and the territory where they are inserted, particularities that allow defining and analyzing them. In the case of family horticultural and flower production, which supplies with fresh products to big urban centers, the specificity of labor-intensive production system, the technologies utilized, the characteristics of the obtained products, their commercialization and their localization, differs substantially from others productive systems of the country. According to diagnosis made by INTA [2004] and other qualitative works in suburbs of Buenos Aires, the difficulties faced by these households are multiples. Among the most important are mentioned the subordination in the commercial chain and the access to financing. This paper seeks account for a territorial development project in the peri-urban region of Gran La Plata, which addresses from an integral perspective, to financing aspects and commercialization to family farmers It focuses on 30 family farmers from La Plata and Berazategui belonging to the project "Banco Social", implemented by Facultad de Ciencias Agrarias y Forestales from UNLP; advancing on an analysis regarding the access to financing and the commercial strategies carried out by the family farmers under studyEn la actualidad, la agricultura familiar ha tomado visibilidad tanto en trabajos académicos como en el diseño de políticas públicas. Si bien se reconocen características propias que la diferencian de la producción empresarial, se presentan de acuerdo al tipo de producción y el territorio donde se inserta, particularidades que permiten definirlas y analizarlas. En el caso de la producción hortiflorícola familiar que abastece de productos frescos a los

  8. Representaciones sociales sobre la problemática de Chagas en un servicio de salud comunitaria del Gran La Plata, Buenos Aires, Argentina.

    Science.gov (United States)

    Sanmartino, Mariana; Amieva, Carolina; Medone, Y Paula

    2017-03-01

    Hablar de Chagas es hablar de una problemática compleja, definida por elementos de carácter biomédico, epidemiológico, sociocultural y político, que se conjugan dinámicamente. En este trabajo buscamos identificar y analizar las representaciones sobre Chagas de los integrantes del equipo de salud de un centro de atención periurbano de la ciudad de La Plata, Argentina. Mediante un abordaje cualitativo, se realizaron entrevistas semiestructuradas y se analizaron las respuestas con la técnica del análisis de contenido. Los resultados mostraron que la mayor parte de las personas entrevistadas no contempla al Chagas como una problemática en su contexto laboral cotidiano y manifiestan un fuerte sesgo biologicista en su formación profesional. Con este trabajo señalamos la urgente necesidad de reflexionar críticamente en torno a la formación de los profesionales de la salud en relación a problemáticas socioambientales complejas de importancia regional, como lo es el Chagas.

  9. Magnetic studies and U Pb geochronology of the Uruguayan dyke swarm, Rio de la Plata craton, Uruguay: paleomagnetic and economic implications

    Science.gov (United States)

    Halls, Henry C.; Campal, Nestor; Davis, Don W.; Bossi, Jorge

    2001-09-01

    A U-Pb age on baddeleyite of 1790±5 Ma has been obtained from a single dyke of the Uruguayan tholeiitic dyke swarm from the Rio de la Plata craton. Palaeomagnetic results from this and 10 other dykes yield two components, one (A) has the following paleomagnetic parameters: declination=12°, inclination=-16°, α95=7°, latitude of paleopole=61°, longitude=-31°, dp=4°, dm=7°, paleolatitude=-8°, whereas another (B), about 20° steeper, has a direction closer to the present Earth's field direction in Uruguay. Neither magnetisation is considered primary, although the A component may represent a composite between B and a primary component. A field test for the primary nature of the remanences was inconclusive, and no primary pole positions of similar age from other South American cratons are available for comparison. The magnetic results demonstrate that darker-coloured andesite dykes that are sought for facing and monument stone (as 'black granite') can be easily differentiated from more andesi-basaltic, lighter coloured, less valuable dykes of the same swarm, using aeromagnetic data. The results suggest that a high resolution airborne magnetic survey could constitute an important exploration tool for the Uruguayan 'black granite' industry.

  10. Adaptógenos: plantas medicinales tradicionales comercializadas como suplementos dietéticos en la conurbación Buenos Aires-La Plata (Argentina

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    Patricia M. Arenas

    2011-07-01

    Full Text Available En el presente trabajo se presentan los resultados de un estudio sobre tres especies de las cuales se comercializan productos considerados adaptógenos: Lepidium meyenii Walp. (Brassicaceae, "maca", Morinda citrifolia L. (Rubiaceae, "noni", y Petiveria alliacea L. (Phytolaccaceae, "pipi". Los datos provienen de estudios en Etnobotánica urbana realizados en la conurbación Buenos Aires-La Plata, se presentan los usos tradicionales de las especies, sus vías de ingreso, comercialización y difusión como suplementos dietéticos en el contexto pluricultural urbano, los modos actuales de empleo y los saberes relacionados, que forman parte del conocimiento botánico local. De este modo, se evalúan las modificaciones en los usos originalmente asignados, como consecuencia de la expansión de los productos en el marco de la globalización, y los cambios consecuentes en los patrones tradicionales de saberes, creencias y prácticas referidos a estos recursos vegetales

  11. “Estudiando cerca de casa”. Un acercamiento desde la perspectiva espacial a la experiencia del Plan FinEs2 en la ciudad de La Plata

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    Federico González

    2016-12-01

    Full Text Available Desde la perspectiva espacial, el presente artículo tiene como objetivo analizar cómo dos espacios, con tradiciones e historias distintas, son transformados por las mediaciones de una política pública y por el trabajo cotidiano que militantes de dos organizaciones llevan a cabo en los barrios donde se encuentran insertos. De esta forma, se intenta contribuir a las discusiones en torno a las relaciones entre espacio y política en el caso de la experiencia de una política pública de terminalidad educativa: el Plan FinEs2. Para ello, trabajamos a partir de dos investigaciones que desde una perspectiva cualitativa analizan las experiencias del Plan FinEs2 en dos barrios de la ciudad de La Plata. Como resultado, pudimos observar las formas en que estos dos espacios son transformados a partir de las relaciones tejidas entre la política, lo educativo y lo espacial.

  12. Benthic communities on hard substrates covered by Limnoperna fortunei Dunker (Bivalvia, Mytilidae at an estuarine beach (Río de la Plata, Argentina

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    Fernando G. Spaccesi

    2012-01-01

    Full Text Available The structure and composition of benthic communities on hard substrates covered by the nonindigenous bivalve Limnoperna fortunei Dunker, the golden mussel, were quantified in the middle zone of the Río de la Plata Estuary (Argentina from April 2001 through March 2002. A total of 26 taxa were recorded. L. fortunei and Nematoda were the central and dominant groups, with a prodigious abundance of over 80%. The prevalence of L. fortunei, rather than the environmental variables, regulated the dynamics of the associated invertebrate fauna. The golden mussel alters both the structure and function of benthic native communities on hard substrates, allows a higher surface available for colonization and refuge, and provides food source to deposit-feeding organisms in the form of organic or residual material. The mussel also increases the abundance and diversity of taxa on hard substrata - such as Oligochaeta, Hirudinea, Tardigrada, Chironomidae, Copepoda, Tanaidacea, and Hydrachnidia. Similarities and nonparametric multidimensional-scaling analyses indicated that the benthic composition had a seasonal variation. L. fortunei has an environmental impact, an ability to invade new freshwater ambiences worldwide and ecological characteristic comparable to those of Dreissena polymorpha Pallas (the zebra mussel of North America and Europe.

  13. The need for true controversies in psychoanalysis: the debates on Melanie Klein and Jacques Lacan in the Rio de la Plata.

    Science.gov (United States)

    Bernardi, Ricardo

    2002-08-01

    Controversies are part of the process of scientific knowing. In psychoanalysis, the diversity of theoretical, technical and epistemological positions makes the debate particularly necessary and by the same token difficult. In this paper, the author examines the function of controversies and the obstacles to their development, taking as examples the debates held in the Río de la Plata (Buenos Aires and Montevideo) during the nineteen seventies, when the dominant Kleinian ideas came into contact with Lacanian thought. The author examines different examples of argumentative discourses, using concepts taken from the theory of argumentation. The major difficulties encountered did not hinge on characteristics pertaining to psychoanalytic theories (i.e. the lack of commensurability between them), but on the defensive strategies aimed at keeping each theory's premises safe from the opposing party's arguments. A true debate implies the construction of a shared argumentative field that makes it possible to lay out the different positions and see some interaction between them and is guided by the search for the best argument. When this occurs, controversies promote the discipline's development, even when they fail to reach any consensus.

  14. Otolith morphology and body size relationships for juvenile Sciaenidae in the Río de la Plata estuary (35-36°S

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    Juan A. Waessle

    2003-06-01

    Full Text Available Seven species of the family Sciaenidae have been reported inhabiting bottom waters of the Río de la Plata estuary. Of these juvenile stripped weakfish (Cynoscion guatucupa, king weakfish (Macrodon ancylodon, whitemouth croaker (Micropogonias furnieri and banded ground drum (Paralonchurus brasiliensis are by far the most abundant. These species are also important prey of several top-predator species among large fishes, seabirds and mammals. In this study we provide new information regarding otolith morphology and body size relationships of juvenile sciaenid fish. The sagittae morphology of juvenile sciaenids showed strong changes in the course of their development (e.g. in overall shape and development of concrescences on the outer surface. Analysing the morphometric relationships, we concluded that otolith length and otolith mass are good indicators of fish standard length and fish weight in all species. If otolith length or mass is used to estimate fish length, the regression explained more than 97% of the variation in all species. All equations relating fish standard length and fish weight for juvenile stages of the species studied explained a very large proportion of the variance in the data. These data will help researchers studying food habits of top predators to determine size and weight of usually juvenile fish-prey from length, broad and/or weight of recovered otoliths.

  15. The Dom Feliciano belt and its relations with the craton of the Rio de la Plata and Punta del Este ground-Geology and geochronology

    International Nuclear Information System (INIS)

    Preciozzi, F.; Peel, E.; Sanchez, L.; Basei, M.; Ledesma, J.; Muzio, R.

    2005-01-01

    This research was framed in an interdisciplinary project, whose main objective was to make an approach to the geological, tectonic and geochronological evolution of Dom Feliciano Belt and adjacent land partners, especially the Río de la Plata Craton and Land Punta del Este. As was proposed in the project, special attention to geochronological studies from geological transects lent controlled. This yielded the expected level major step forward, not only with regard to the age of different units, but what makes the establishment of an adequate stratigraphy of them. Similarly, geochemical, petrographic and geochronological studies allowed essentially make geotectonic and geologic correlations with the southern portion of Brazil and the western portion of the land I africanos.lo expand involving more project goals in si.En effect began to manifest as a need to know the evolution of equivalent units both in the southern portion of Brazil and Africa Occidental.Estos fundamentalmnete work with West Africa were made with contributions from CONICYT Project 6009 under Projects Geological Correlation 438, 450 and 478 .this pertimitio exchange ideas with leading scientists worldwide many of whom ended up collaborating with it

  16. Medición de placas astrométricas obtenidas con el telescopio Astrográfico de La Plata

    Science.gov (United States)

    di Sisto, R. P.; Orellana, R.

    El Observatorio de La Plata cuenta con un gran número de placas de asteroides y cometas obtenidas con el telescopio astrográfico, que cubren gran parte del cielo del hemisferio sur. En 1996 se recopilaron y clasificaron 2187 placas (Beca para estudiantes de la AAA 1996) de las cuales 2031 corresponden a asteroides. Los datos de cada placa se volcaron en una base de datos creada para facilitar su manejo y preservar la información. A partir de este trabajo se revisaron los MPC electrónicos y se identificaron aquellas placas de asteroides pertenecientes a nuestra base de datos cuyos resultados no fueron publicados en los mismos. De un total de 400 placas que no aparecían publicadas sobresalía un paquete constituído por 40 placas obtenidas en 1977. Estas últimas fueron reducidas utilizando las posiciones y movimientos propios de las estrellas de referencia obtenidas del catálogo SAO 2000 dadas para el sistema FK5. Las posiciones calculadas fueron enviadas y publicadas en los Minor Planet Circulars (MPC).

  17. Los reales de minas de la caja de Guadalajara durante el siglo XVIII: Circuitos comerciales y producción de plata

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    de León Meza, C. René

    2011-08-01

    Full Text Available This article shows the economic significance of the group of mines that belonged to the jurisdiction of the «Caja de Guadalajara». The novelty lies in that local historiography had erroneously labeled these mining camps as being small. Recent studies show that they were not so small after all. These groups of mines were the focal point of the economy of a vast region and triggered the development of agriculture, livestock and trade activities. This article reveals the nexus between the fluctuations in silver production and events in Europe.

    Este artículo da a conocer la importancia económica que tuvo un conjunto de reales de minas que perteneció a la jurisdicción de la caja de Guadalajara. Es novedoso porque por primera vez son estudiados aquéllos que la historiografía local ha considerado erróneamente como «pequeños reales de minas». Estas explotaciones fueron el eje articulador de la economía en una vasta región que impulsó el desarrollo de la ganadería, agricultura y comercio. Vincula las fluctuaciones en la producción de plata con sucesos ocurridos en Europa.

  18. Estudios etnobotánicos en la conurbación Buenos Aires-La Plata, Argentina: Productos de plantas medicinales introducidos por inmigrantes paraguayos

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    Julio A. Hurrell

    2016-01-01

    Full Text Available Este trabajo incluye resultados parciales de una línea de investigación en Etnobotánica urbana, que estudia los conocimientos locales sobre las plantas, sus partes y productos derivados en la conurbación Buenos Aires-La Plata. Se incluyen productos de plantas medicinales de reciente ingreso en el área de estudio a través de inmigrantes oriundos de Paraguay. Los productos corresponden a 10 especies: Achyrocline alata(“jateí-ka’á”, Baccharis gaudichaudiana (“jaguareté-ka’á”, Cuphea lysimachioides(“ysypó-peré”, Euphorbia serpens(“tupasý-kambý”, Genipa americana(“ñandypá”, Helietta apiculata(“yvyra ovy”, Lycopodiella cernnua(“itápotý”, Rhynchosia balansae(“urusú-he’ě”, Stevia rebaudiana(“ka’á-he’ě” y Victoria cruziana(“jacaré-yrupé”. Para cada caso se indican sus productos, muestras de referencia, usos asignados, actividad biológica y efectos estudiados. La presencia de los productos de estas especies en el área metropolitana indica un aumento de la diversidad biocultural local, tanto de plantas y productos como de sus conocimientos asociados.

  19. [Organization and preservation of the collection of pathogenic and fungal symbionts of insects and other arthropods from CEPAVE (CONICET-UNLP), La Plata, Argentina].

    Science.gov (United States)

    Gutierrez, Alejandra Concepción; Tornesello-Galván, Julieta; Manfrino, Romina Guadalupe; Hipperdinger, Marcela; Falvo, Marianel; D'Alessandro, Celeste; López Lastra, Claudia Cristina

    The collection of fungal pathogens and symbionts of insects and other arthropods of the Centro de Estudios Parasitológicos y de Vectores, La Plata, Argentina, is unique because it preserves in vivo and in vitro cultures of fungal pathogens. This culture collection is open for research, teaching, consulting services, and strain deposit. It contains 421 strains belonging to 23 genera (16 Ascomycota, 4 Entomophthoromycotina, 2 Glomeromycota and 1 Oomycota), and the cultures are preserved by different methods such as cryopreservation in freezer at -20°C and -70°C, paper, distilled water and lyophilization. Fungi were isolated from insects, other arthropods, and soil (by using insect baits and selective media). Species were identified by morphological features and in a few strains by molecular taxonomy (PCR of rDNA). This collection is a reference center for species identification/certifications, research and teaching purposes, strain deposit, transference and consultancy services, and its overall goal is to preserve the fungal germplasm and ex situ diversity. Most of the strains are native of Argentina. The collection was originated in 1988 and is registered in the Latin American Federation for Culture Collections and in the World Federation of Culture Collections. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  20. Archivo y relato en el Río de la Plata Colonial. El difícil discurso de la violencia

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    Loreley El Jaber

    2013-11-01

    Full Text Available La propuesta en esta ocasión es la de abordar la relación entre archivo y relato en el Río de la Plata durante el siglo XVI y, para esto, se analizará una información levantada por Cabeza de Vaca en su defensa, fechada en 1544, porque en ella se da lugar a la aparición de un conjunto de voces de españoles que denuncian los atropellos, gravámenes y “vejaciones” sufridas por parte de sus pares en procura de la cobranza del quinto. Estos discursos, no reproducidos por otros textos impresos durante el mencionado siglo, plantean una problemática compleja: la relación entre ley, violencia y espacio conquistado; pero también, otra de distinto orden: los alcances y efectos de discursividades como estas, devenires de un relato cruel detenido en el tiempo del archivo judicial. El presente trabajo busca abordar ambas problemáticas así como darle un lugar a esta serie de voces olvidadas.

  1. Pesca y puerto en la ciudad de Mar del Plata. Relaciones íntimas entre una actividad económica transformada y un espacio deteriorado

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    Gonzalo Julián Yurkievich

    2013-12-01

    Full Text Available La actividad pesquera argentina experimentó durante las décadas de 1980 y de 1990 profundas transformaciones estructurales que impactaron con fuerza en las formaciones sociales relacionadas en forma directa e indirecta con la industria. La trasformación involucró, además, un deterioro del espacio y del medio ambiente de la zona portuaria de la ciudad de Mar del Plata. El presente análisis apunta a identificar este deterioro, a explicar los motivos por los cuales se generó el mismo, y a establecer los órdenes de competencia y responsabilidad en el tema. Partimos de la idea de que durante el régimen de acumulación capitalista denominado recurrentemente como neoliberal, existió una retracción del Estado y una reducción de la inversión pública en infraestructuras así como una creciente externalización del costo ambiental por parte de los privados, generándose, así, un creciente deterioro del medio ambiente urbano en las ciudades argentinas.

  2. La estructuración del comercio y la navegación desde el río de la Plata a Cuba

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    Asdrúbal Silva, Hernán

    1994-12-01

    Full Text Available Not available.

    El presente trabajo tiene por objeto estudiar la estructuración del tráfico y las exportaciones desde el Río de la Plata a La Habana, teniendo en cuenta básicamente la conjunción de tres factores: a el desenvolvimiento de la industria saladeril rioplatense, que hizo de las carnes el elemento esencial de exportación hacia La Habana, b la expansión del sistema esclavista y la transformación productiva cubana, que generó un interesante mercado, c la rápida conformación de una estructura de comercialización y transporte. Aspectos tales como los vinculados a la producción regional y el establecimiento de los nexos comerciales, el movimiento marítimo y las variantes en la navegación, la significativa presencia de catalanes y norteamericanos en el tráfico, los volúmenes de las principales exportaciones, etc., adquieren significación dentro del proceso histórico que les toca vivir a las posesiones hispanas desde fines del siglo XVIII hasta la Revolución independentista.

  3. El rol femenino a través de los litigios familiares en el Virreinato del Río de la Plata (siglos XVIII y XIX

    Directory of Open Access Journals (Sweden)

    Viviana Kluger

    2014-06-01

    Full Text Available El objeto de este trabajo es analizar el rol femenino en el litigio familiar, a efectos de determinar la presencia de las mujeres a la hora de reclamar el cumplimiento de los deberes y derechos conyugales y paterno filiales en los pleitos entablados en el Virreinato del Río de la Plata. Se trata de medir los ajustes y desajustes, el conformismo y la contradicción entre el modelo propuesto desde la ley y la doctrina, y de contrastar esos esquemas con la praxis judicial. Se presenta primero un análisis del marco legal, para pasar luego al estudio de la asignación de roles familiares, expresada a través de la doctrina canónica y jurídica española de los siglos XVI a XIX, así como de la literatura de la época. Se tratan también el poder de corrección y el deber de subordinación, el rol femenino a través de los litigios familiares, en la defensa del honor y en las alianzas matrimoniales, y se consideran las variaciones según el tiempo, el espacio y la clase social. Por último se exponen unas consideraciones finales acerca de la eventual brecha entre el modelo y la realidad.

  4. PLATA Y CASTAÑAR (VILLAVERDE, MADRID. UN EJEMPLO DE INTERVENCIONES EN EL BORDE DE LA CIUDAD. URBANISMO POR Y PARA EL REALOJO

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    Antonio J. Palacios García

    2009-01-01

    Full Text Available En las ciudades españolas todavía persisten un buen número de áreas que presentan una serie de carencias urbanísticas, sociales, económicas, ambientales u otras. Es lo que se conoce como barrios desfavorecidos urbanos. Para esta aportación se analiza el caso de una zona del sur metropolitano madrileño como es la de Plata y Castañar. En dicho barrio vamos a tratar de desentrañar el proceso de sustitución y creación de la edificación existente, los problemas acontecidos durante el desarrollo de la intervención, sus dificultades y las herramientas empleadas. Un área donde se ha intervenido frente al desfavorecimiento de forma sectorial, sobre un único elemento, el espacio construido. Aún a costa de la persistencia en el tiempo de otras graves carencias (fundamentalmente de tipo social. Una forma de intervenir muy criticada por cuanto supone la agrupación en un mismo territorio de una población desfavorecida.

  5. Gigantic oocytes in the deep sea black coral Dendrobathypathes grandis (Antipatharia) from the Mar del Plata submarine canyon area (southwestern Atlantic)

    Science.gov (United States)

    Lauretta, Daniel; Penchaszadeh, Pablo E.

    2017-10-01

    The black coral Dendrobathypathes grandis (Cnidaria: Antipatharia) is studied for the first time in the southwestern Atlantic off Argentina. This is the only antipatharian reported from the Atlantic between 35°S and 54°S. Eleven specimens were collected at depths of 819-2204 m during three expeditions to the Mar del Plata submarine canyon (2012-2013); seven were females. The species is gonochoric, and the polyps in female colonies contain up to nine oocytes per polyp, which can reach 1500 μm in diameter. In contrast, the largest oocyte currently reported for antipatharians is 500 μm, and usual diameters do not exceed 200 μm. These large oocytes have over 20 times more volume than the biggest oocyte reported, but over 800 times more volume when compared with the common oocyte size of the group. Sperm size and morphology is similar to previous data from other species. As in previous studies, neither embryos nor larvae were found in any specimens. This species was previously only reported from waters off South Georgia Island, and so these specimens expand the known distribution north by 1800 km.

  6. The basement of the Punta de Este Terrane: A meso proterozoic heritage at the eastern border of Rio de La Plata craton

    International Nuclear Information System (INIS)

    Preciozzi, F.; Peel, E.; Sanchez, L.; Basei, M.

    2005-01-01

    U-Pb zircon ages between 1000 and 900 Ma corresponding to the nuclei of zircon crystals extracted from the basement of the Punta del Este Terrane (Eastern Uruguay) allowed the correlation of the protoliths of this domain with rocks attributed to the Namaqua Belt in Southwestern Africa. SHRIMP ages obtained for the ortho gneissic rocks allowed to place at ca. 750 Ma the generations of gneisses and migmatites. Differently from what occurred in Africa, reworking of this crustal segment during the Brasiliano-Pan african orogenesis was very intense, reaching the granulite facies around 640Ma. Acid volcanic and volcaniclastic rocks (Sierra de Aguirre Formation) with ages around 570 Ma, late sedimentary basins (San Carlos Formation) and post-tectonic granitoids (Santa Teresa and José Ignacio batholith s) mark the end of the events related with the Brasiliano/Pan-African orogenesis. The final collision between the Punta del Este Terrane and the western domains represented by the Dom Feliciano Belt and the Río de La Plata Craton may have occurred at around 535 Ma

  7. [Infection by Bordetella pertussis and bordetella parapertussis in cases of suspected whooping cough (2011-2015) in Mar del Plata, Argentina].

    Science.gov (United States)

    Lavayén, Silvina; Zotta, Claudia; Cepeda, Marcela; Lara, Claudia; Rearte, Analia; Regueira, Mabel

    2017-01-01

    . To classify the study population in the Argentinian National Health Surveillance System framework, determine the proportion of infection by Bordetella pertussis and Bordetella parapertussis, and identify factors associated with the cases of suspected whooping cough attended to in the city of Mar del Plata and its outskirts during the period 2011- 2015. An observational and descriptive study was carried out. Clinical cases with suspicion of whooping cough were diagnosed by laboratory. The laboratory studies consisted of culture, PCR, and serology using the ELISA technique. A total of 572 cases were evaluated. The female sex was the most frequent (51.9%). The most frequent age range was 2 to 17 moths (51.1%; 290/568), which was also the group with the most confirmed cases. Only 47.8% (155/324) of the population studied had complete vaccination for their age. Whooping cough due to B. pertussis was confirmed in 15.5% (89/572) of cases and one case with B. parapertussis. Those cases that had contact with a coughing relative were significantly associated with the confirmation of Bordetella spp. by the laboratory (odds ratio: 3.3; 95% confidence interval: 1.9-5.4). The results show the need to suspect whooping cough and diagnose it early in children, adolescents, and adults in order to better control the disease. Likewise, continuing prevention and containment measures are fundamental in decreasing the circulation of the causal agent.

  8. Una experiencia universitaria frustrada. Persecución y represión antes del golpe en la Universidad de Mar del Plata

    Directory of Open Access Journals (Sweden)

    Gastón Julián Gil

    2007-11-01

    Full Text Available It is widely accepted that during the last military dictatorship in Argentina, human and social sciences were privileged focus of ideological persecution and governmental attacks. Nevertheless, these serious persecutions and attacks did not begin with the coup d'etat of March 24 of 1976. Almost two years before, during the presidency of María Estela Martínez, Argentinean universities were specially chosen by para-governmental terrorism, which was symbolized by the infamous Minister of Welfare, José López Rega, as places to develop its criminal actions. As a particular case, the School of Anthropology at the University of Mar del Plata suffered a dramatic process of dismantlemenjt from the middle of 1974 to the end of 1975, when all the applications for the School of Anthropology were cancelled. Drawing both on official documents of the university and on testimonies of people who were engaged in that experience, in this article I aim at accounting for a historical context which laid the foundations of a tragic path that was going to be continued by the military process.

  9. Memoria individual y nostalgia colectiva en Uruguay: la fragmentación del tiempo en los relatos enmarcados de Tijeras de Plata de Hugo Burel

    Directory of Open Access Journals (Sweden)

    Giuseppe Gatti

    2012-12-01

    Full Text Available Dentro de la narrativa hispanoamericana del siglo XX, el presente estudio analiza el papel desempeñado por los procesos de rememoración en el espacio literario uruguayo contemporáneo. El trabajo se propone concentrar la atención en las dinámicas de recuperación del tiempo pasado en la obra del montevideano Hugo Burel (1951, y en particular en su novela Tijeras de Plata (2003. La primera parte de nuestro estudio se centrará en el impacto sobre una novela de ambientación típicamente montevideana que plasma a nivel simbólico los cambios geo-sociales que han caracterizado el espacio uruguayo a partir de la segunda mitad del siglo XX (descentralización poblacional urbana; paulatino quiebre en el tejido social, cultural y económico de barrios enteros; desaparición de vestigios materiales e inmateriales del pasado arcádico. Se pondrán en relación estos fenómenos con las formas narrativas utilizadas (relatos enmarcados, lo cual nos ofrecerá la oportunidad de reflexionar sobre otro tipo de fragmentación, de naturaleza extra-literaria. El objetivo consistirá en identificar una relación de causa/efecto entre la literatura y un determinado espacio social: en el caso de Uruguay, nos referimos a esa sensación de «fractura» con el pasado que experimentó, a todo nivel, la sociedad uruguaya. En la segunda parte, se evidenciará cómo Tijeras de Plata es una novela de reivindicación de un pasado desaparecido, que construye gran parte de su esencia como «narración de la memoria» sobre la evidencia –y no la condena– del proceso de pauperización experimentado por amplias zonas urbanas de la ciudad. Se centrará la atención en la manera en que la novela bureliana recupera el espacio del recuerdo, no en términos melancólicos ni de exaltación nostálgica de un pasado nunca olvidado. Se intenta, por el contrario, demostrar cómo la doble operación de rescate (por un lado, de las memorias individuales relacionadas con el barrio; por

  10. Los colegios nacionales y sus estudiantes: Mujeres, gringos e hijos de inmigrantes en la primera mitad del siglo XX (Mar del Plata, 1919-1929

    Directory of Open Access Journals (Sweden)

    Francisco Ramallo

    2016-08-01

    Full Text Available Nuestra investigación se propone desestabilizar el relato oficial que la historiografía de la educación reprodujo y consolidó del bachillerato argentino (y con él el de la enseñanza secundaria a través de los “lugares comunes”, prejuicios analíticos, lecturas “a priori” y miradas “desde arriba” que caracterizaron a los relatos sobre los colegios nacionales. Todo ello a partir del análisis de caso de un colegio nacional: el de Mar del Plata. Específicamente en este artículo pretendemos identificar a los estudiantes de los colegios nacionales en la primera mitad del siglo XX. Para ello en la primera parte recuperamos los estudios realizados al respecto e indagamos las interpretaciones historiográficas que los respaldan; y en la segunda parte nos concentramos en un estudio empírico de los alumnos de este colegio. Nuestro argumento es que si bien los colegios se caracterizaron por representar una enseñanza “tradicional”, “selectiva” y “elitista”, en la práctica actuaron como espacios abiertos y permeables al cual accedieron estudiantes de diferentes lugares en la escala social (o al menos de sectores sociales más amplios que los reconocidos por los discursos de la época y por los relatos al respecto. De este modo remarcamos que el bachillerato marplantense fue conformado por actores poco considerados por la historiografía de la educación: las mujeres (que representaron un tercio del alumnado y los gringos e hijos de inmigrantes (cuya cifra superó las dos terceras partes de los jóvenes.

  11. Use of phytoplankton assemblages to assess the quality of coastal waters of a transitional ecosystem: Río de la Plata estuary

    Science.gov (United States)

    Sathicq, María Belén; Gómez, Nora; Bauer, Delia Elena; Donadelli, Jorge

    2017-11-01

    Among the estuarine ecosystems under anthropogenic stress, the Río de la Plata can represent a case study to help identify phytoplanktonic species diagnosing and warning about water quality changes. The freshwater tidal zone on the coast of Argentina is used for several purposes, including recreational and navigational activities and the provision of drinking water. We analyzed the relationship between the abundance of the phytoplanktonic species, changes in water quality (linked to enrichment with nutrients and organic matter) and the land use on the coast of Argentina. A canonical correlation analysis (CCA) allowed us to identify two environmental gradients, one related to anthropogenic activities, where the most influential factors were BOD5, DIN, PO43- and DO, and a second gradient related to turbidity and conductivity. The relative abundances of 24 species were significantly correlated with the deterioration of the water quality. This set of tolerant species is mostly composed of taxa considered C-strategists, and the most represented group was the Chlorococcalean algae. The percentage of this group can provide an early warning indicator of the impairment of the water quality; its abundance exceeded 30% at those sites with a bad water quality (reaching 19000 cell mL-1), and were less than 15% (300 cell mL-1) in sites with a good water quality. The use of a reduced group of species constitutes a potential tool for monitoring, complementing another common indicators such as chlorophyll a or the total density of phytoplankton. Considering that most of these tolerant species are widely distributed it is possible to employ them as a biomonitor in other freshwater zones of temperate estuaries.

  12. Hábitat y historia de vida de Pachychelles laevidactylus (Crustacea, Anomura, Porcellanidae en el intermareal rocoso de Mar del Plata, Argentina

    Directory of Open Access Journals (Sweden)

    Martina Daniela Camiolo

    2016-01-01

    Full Text Available RESUMEN Se analizó la estructura del hábitat, el crecimiento relativo, la heteroquelia, la estructura poblacional, la madurez morfométrica y la fecundidad de Pachycheles laevidactylus Ortmann, 1892, durante Abril, Mayo y Junio del 2005, en sustratos naturales de Mar del Plata, Argentina (38°02'S, 57°31'W. La cobertura algal, la exposición al oleaje y el tiempo de inmersión varió de manera significativa entre estratos y entre meses. La morfometría de las quelas no manifestó diferencias entre sexos. Las hembras mostraron el abdomen más grande que los machos. Si bien existió la heteroquelia, no se detectó lateralidad. Las tallas (ancho de caparazón estuvieron comprendidas entre 0.67 mm a 9.3 mm para los machos, y entre 1.07 mm a 10.65 mm, para las hembras. La densidad de organismos varió entre meses y entre los estratos. La estructura poblacional, para el periodo de estudio, se explicó en función de la estructura del hábitat. La madurez morfométrica de las hembras fue registrada a los 4.38 mm de ancho de caparazón. El número de huevos se correlacionó positivamente con la talla de las hembras ovígeras con un mínimo de 2 huevos y un máximo de 160, pero esa relación dependió del avance en el desarrollo de los embriones.

  13. El Proceso de precarización en el mercado de trabajo del Gran La Plata. Principales características y tendencias actuales (2003-2004

    Directory of Open Access Journals (Sweden)

    Héctor Luis Adriani

    2005-01-01

    Full Text Available The aim of this paper is to identify of the main features and trends of precarious work in Great La Plata, considering the current national economic dynamics. Taking as benchmark the "full" employment, different degress of precariousness can be found according to the lack of features that characterize said fullness. Thus, there would be a gradation of situations, from a maximum reference in the "full" employment to a minimum one in the absolute unemployment. The analysis is based on the information provide by a survey called Encuesta Permanente de Hogares (EPH, which comprises the time between the second semester in 2003 and the first one in 2004, since after their restructuring EPH only provides information on that period so far. The results show that in the region, precarious jobs amount to 39.3 of the economically active population in the first semester in 2004. If the unemployed are included, over 50 of the population undergo employment problems and there exists pressure of the demanding underemployed sector on the labor market. In the public sector, 16.4 of the people employed are precarized, and the percentage rises to 34 if the beneficiaries of unemployment programs are included. In the private sector, precarious employment reaches 54. Regarding the evolution of per capita income, the levels reached are below those earned before the 2002 devaluation, even within the groups of employed people whose purchasing power improved between 2003 and 2004. The main contributions of this paper lie in the identification, quantification and characterization of precarious employment in the region in the post-devaluation period through the analysis of the EPH Data Base.

  14. Short time-scale wind forced variability in the Río de la Plata Estuary and its role on ichthyoplankton retention

    Science.gov (United States)

    Simionato, C. G.; Berasategui, A.; Meccia, V. L.; Acha, M.; Mianzan, H.

    2008-01-01

    The Río de la Plata Estuary presents a strong bottom salinity front located over a submerged shoal. Apparently favored by retention processes, it is a spawning ground for several coastal fishes. This estuary is very shallow and essentially wind driven and, moreover, in time scales relevant to biota, estuarine circulation is wind dominated and highly variable. Two intriguing questions are, therefore, how this system can favor retention and what the involved mechanisms are. This paper qualitatively explores mechanisms involved in the estuary where retention is favored applying numerical simulations in which neutral particles - simulating fish eggs and early larvae - are released along the bottom frontal zone and tracked for different wind conditions. Results suggest that retentive features can be a consequence of estuarine response to natural wind variability acting over bathymetric features. For winds from most directions, particles either remain trapped near their launching position or move northeastward to southwestward along the shoal. As alternation of winds that favor along-shoal motion is the dominant feature of wind variability in the region, a retentive scenario results from prevailing wind variability. Additionally, winds that tend to export particles with a poor chance of being restored to the front are neither frequent nor persistent. Results show, therefore, that physical forcing alone might generate a retentive scenario at the inner part of this estuary. The physical retention mechanism is more effective for bottom than for surface launched particles. Wind statistics indicate that the proposed mechanism has different implications for retention along the seasons. Spring is the most favorable season, followed by summer, when particles would have a larger propensity to reach the southern area of the estuary (Samborombón Bay). Fall and winter are increasingly less favorable. All these features are consistent with patterns observed in the region in

  15. Nuevas oportunidades como experiencia. Jóvenes y desigualdad en el caso del Plan FinEs2 en el Gran La Plata

    Directory of Open Access Journals (Sweden)

    María Laura Crego

    2015-12-01

    Full Text Available Este artículo tiene como objetivo abordar la articulación de tres dimensiones de la desigualdad social —segregación urbana, segregación educativa y segmentación del mercado de trabajo— que configuran las posiciones desiguales de los jóvenes estudiantes del Plan FinEs2 en el espacio social. Al mismo tiempo, nos proponemos esbozar algunas líneas de análisis para el abordaje de las repercusiones de dicha experiencia en las trayectorias de los jóvenes. Para ello, desde una perspectiva cualitativa, trabajamos con entrevistas en profundidad a jóvenes estudiantes y a docentes del Plan FinEs2 en el Gran La Plata durante el período 2013-2014. Como resultado pudimos observar que la segregación urbana presenta profundas cercanías con las desigualdades en el mercado de trabajo y en el sistema educativo. Estas dimensiones de la desigualdad se encadenan, se combinan y se potencian en un proceso en el que las desventajas se acumulan y dan como resultado signos de la desigualdad social y su reproducción. Sin embargo, dimos cuenta de cuatro movimientos que el recorrido de la experiencia habilita: posiciones frente a las situaciones de aprendizaje, reconocimiento de la posibilidad de complementar actividades laborales y de formación, cambios en las posiciones en sus dinámicas familiares y en espacios de trabajo y significaciones en torno al título secundario

  16. Life-history, substrate choice and Cytochrome Oxidase I variations in sandy beach peracaridans along the Rio de la Plata estuary

    Science.gov (United States)

    Fanini, L.; Zampicinini, G.; Tsigenopoulos, C. S.; Barboza, F. R.; Lozoya, J. P.; Gómez, J.; Celentano, E.; Lercari, D.; Marchetti, G. M.; Defeo, O.

    2017-03-01

    Life-history, substrate choice and Cytochrome Oxidase I (COI) sequences were analysed in populations of two peracaridans, the supralittoral talitrid Atlantorchestoidea brasiliensis and the intertidal cirolanid Excirolana armata. Three populations of each species, from beaches with similar grain size and located at different points along the natural gradient generated by the Rio de la Plata estuary were analysed. Abundance of E. armata increased with distance from the estuary, while the opposite trend was observed for A. brasiliensis. The proportion of females decreased towards high salinities for both species, significantly for E. armata. A test on substrate salinity preference revealed the absence of patterns due to active choice in E. armata. By contrast, A. brasiliensis showed no preference for the population closer to the estuary, while individuals from the other two sites significantly preferred high salinity substrates. Mitochondrial COI sequences were obtained from A. brasiliensis specimens tested for behaviour. Sequence analysis showed the population from the intermediate site to differ significantly from the other two. No significant genetic differentiation was instead found between populations from the two most distant sites, nor between individuals that expressed different salinity preference. Results showed that diverse sets of traits at the population level enable sandy beach species to cope with local environmental changes: life-history and behavioural traits appear to change in response to different ecological conditions, and, in the case of A brasiliensis, independently of the population structure inferred from COI sequence variation. Information from multiple traits allowed detection of population profiles, highlighting the relevance of multidisciplinary information and the concurrent analysis of field data and laboratory experiments, to detect responses of resident biota to environmental changes.

  17. Astronomía para ciegos y amblíopes. Proyecto de construcción de un planetario especial en la ciudad de Mar del Plata

    Science.gov (United States)

    Musso, S.

    ?`Qué es la Astronomía para Ciegos?. El trabajo es una adaptación en base a la escala de magnitudes de Hipparco que cambia el concepto de luz por una adaptación sonora, donde las estrellas de magnitud 6 se escuchan en 10 dB, más o menos lo que consideramos el umbral de la audición humana. Quienes no escuchan muy bien no pueden escuchar las magnitudes 6, de la misma manera que muchos de nosotros, que no poseemos una visión perfecta, no podemos observar esas mismas estrellas en el cielo (más allá de la polución). A los astros de magnitud 5 vamos a relacionarlos a un sonido en 20 dB. Y así sucesivamente. También los colores estarán representados en una convención de graves a agudos y lo mismo algunas características del cielo. Por ejemplo, la Vía Láctea se mostrará como un ``ruido", como bien nos lo hicieron ver nuestros futuros destinatarios. En Mar del Plata nos encontramos ya trabajando en un proyecto que tiene como objetivo final la construcción del Primer Planetario Acústico del Mundo, una herramienta para la enseñanza de la astronomía, un espacio para la lucha contra la discriminación del discapacitado y una posibilidad de ``ver el cielo de un modo diferente".

  18. The Dom Feliciano belt (Brazil-Uruguay)and its fore land (Rio de la Plata Craton): framework, tectonic evolution and correlations with similar terranes of southwestern Africa

    International Nuclear Information System (INIS)

    Basei, M.; Siga, O.; Masquelin, H.; Harara, O.; Reis Neto, J.; Preciozzi, F.

    2000-01-01

    The Dom Feliciano Belt (DFB) stretches for ca. 1,200 km along southeastern Brazil and eastern Uruguay, with an average width of 150 km. From its northern limit in Santa Catarina to its termination m Uruguay, DFB is internally organized according three crustal segments characterized, from southeast to northwest, by a Granitoid belt (calci-alkaline to alkaline granitoid rocks deformed to different degrees); a Schist belt (volcano-sedimentary rocks metamorphosed from green schist to amphibolite facies), and a Fore land belt (sedimentary and anchimetamorphic volcanic rocks), the latter situated between the Schist belt and the old western terranes. Despite discontinuously covered by younger sediments, the continuity of these three segments is suggested by the similar lithotypes and structural characteristics, as well as by the gravimetric geophysical signature.In this work, DBF is interpreted as the product of successive subduction s and collisions related to the agglutination of different terranes generated or intensely reworked from the Neoproterozoic to the Cambrian, during the Brasiliano and Rio Doce orogenesis, with maximum time starting at 900 Ma (opening of the Adamastor Ocean) and ending at 530 Ma (deformation of the fore land basins) related to the tecto no-magmatic events associated with the formation of the Western Gondwana.Besides the Neoproterozoic DFB and its fore land, the Rio de la Plata Craton and the Luis Alves Microplate, constituted by Paleoproterozoic gneissic-migmatitic rocks, two other tectonic units can be recognized in southeastern Brazil and eastern Uruguay: the Sao Gabriel Block (RS) where Neoproterozoic juvenile material can be characterized in regional scale (in great part associated with an island are), and the Punta del Este Terrane, which presents, in southern Uruguay, an ortho gneiss basement with ages around 1,000 Ma and a meta sedimentary cover (Rocha Group), which can correspond in the South-American portion, to the Namaqua and Gariep

  19. POTENCIALIDADES Y LIMITACIONES AMBIENTALES EN EL ÁREA DE INTERFASE URBANA-RURAL DE LA CIUDAD DE MAR DEL PLATA (PROVINCIA DE BUENOS AIRES, ARGENTINA): UNA CONTRIBUCIÓN AL ORDENAMIENTO TERRITORIAL

    OpenAIRE

    Ferraro, Rosana; Zulaica, Laura

    2012-01-01

    El periurbano de Mar del Plata exhibe una alta heterogeneidad de usos de la tierra característicos de las zonas de transición. El ordenamiento de estos espacios demanda la identificación de potencialidades y limitaciones ambientales que favorecen o condicionan el desarrollo de actividades urbanas y rurales. Tomando como referencia los antecedentes existentes en el área, el presente trabajo tiene como objetivo evaluar la aptitud de las tierras del periurbano marplatense para distintos tipos de...

  20. Identification of Races 0 and 2 of Cladosporium fulvum (syn Passalora fulva) on Tomato in the Cinturón Hortícola de La Plata, Argentina

    OpenAIRE

    Rollán, María Cristina; Protto, Victoria; Medina, Rocío; López, Silvina Marianela Yanil; Vera Bahima, José; Ronco, Blanca Lía; Saparrat, Mario Carlos Nazareno; Balatti, Pedro Alberto

    2013-01-01

    Surveys aimed at evaluating the incidence and severity of a new disease that developed in greenhouses cultivated with tomato (Solanum lycopersicum L.) were performed during 2009 and 2010 in greenhouses of the cultivars Elpida (Enza Zaden) and Colibrí (Clause) in an area of tomato production known as the Cinturón Hortícola de La Plata (the “horticultural belt of La Plata”). The disease had a 100% prevalence and 90% incidence within the ten 250 m greenhouses that were monitored in 2009, 2010, a...

  1. Análisis de la morosidad tributaria de las empresas aplicando técnicas borrosas y estadísticas. El caso de Mar del Plata. Segunda parte

    OpenAIRE

    Mallo, Paulino E.; Artola, María Antonia; Zanfrillo, Alicia Inés; Morettini, Mariano; Galante, Marcelo Javier; Busetto, Adrián Raúl; Pascual, Mariano Enrique

    2007-01-01

    Continuando con el objetivo buscado en el trabajo presentado en el Coloquio de Estadística del año 2006, en esta oportunidad aportamos una nueva ponencia que amplía las metodologías utilizadas en aquella oportunidad, a la vez que profundiza las conclusiones a las que se había arribado entonces. El propósito es caracterizar el comportamiento de los indicadores contables de distintas empresas de pequeña y mediana envergadura del medio socio-productivo de la ciudad de Mar del Plata que puedan in...

  2. Análisis de la gestión integral de los residuos sólidos urbanos en Mar del Plata desde un enfoque económico

    OpenAIRE

    Leis, Alejandro Nahuel

    2015-01-01

    El manejo de los residuos sólidos urbanos en Argentina conlleva principalmente dos problemáticas económicas: su elevado peso relativo en los presupuestos municipales y sus impactos ambientales, que constituyen externalidades negativas. Este trabajo analiza el sistema actual de recolección de residuos sólidos domiciliarios de la ciudad de Mar del Plata en vista de la disposición municipal que promueve la separación en origen entre orgánicos y reciclables que, a su vez, constituye uno de los ej...

  3. Las marcas del trabajo: un estudio sobre las condiciones de trabajo y la salud de los trabajadores y las trabajadoras de una clínica de medicina privada de la ciudad de La Plata (2016)

    OpenAIRE

    Malleville, Sofía

    2017-01-01

    La presente tesina analiza la configuración de las condiciones laborales y su relación con el proceso salud-enfermedad de los trabajadores y trabajadoras de una clínica de medicina privada ubicada en el casco urbano de la ciudad de La Plata, durante el año 2016. Dicha institución se inscribe en el complejo entramado que reviste el sistema de salud en nuestro país, caracterizado por su escaza articulación y elevada segmentación. A su vez, la clínica privada posee una serie de particularidades ...

  4. The autonomy of the University and political intervention in the trajectories of leadership and academics groups in Natural Science of The Universidad Nacional de La Plata. 1930-1955

    Directory of Open Access Journals (Sweden)

    Germán Flavio Soprano Manzo

    2009-11-01

    Full Text Available This article analyze two process connect in one university institution. In the first part, study the autonomy's forms of the institutional organization discipline produced for the professors and investigators of the Institute of the Museum and the Superior School/ Faculty of the Natural Sciences in the Universidad Nacional de La Plata between 1935 and 1946. In the second part, study two social situations - the university interventions of the years 1946 and 1955- where the political of the National State produced changes in the trajectories of this academics. We explore this relationship in the leadership and academics groups in geology, paleontology, zoology, botanic and anthropology.

  5. La arquitectura “monumental” de la ciudad de La Plata a través del ejercicio independiente de los profesionales italianos durante el período fundacional : El caso del “Eje Avenida Monteverde”

    OpenAIRE

    Carbonari, Fabiana Andrea

    2010-01-01

    El valor simbólico y material aportado en el proceso de construcción del paisaje urbano de la ciudad de La Plata por la inmigración italiana es preeminente durante sus primeros cincuenta años de vida –1882 a 1932-. Entonces, resulta oportuno reflexionar sobre el ejercicio independiente de la profesión de los arquitectos, ingenieros y técnicos peninsulares. En tal sentido, la metodología de trabajo propuesta consiste en el análisis de las relaciones entre el orden político, el socio-cultura...

  6. Synthesis and characterization of PdAg as a catalyst for oxygen reduction reaction in acid medium; Sintesis y caracterizacion de PdAg como catalizador para la reaccion de reduccion de oxigeno en medio acido

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Casillas, D. C.; Vazquez-Huerta, G.; Solorza-Feria, O. [Centro de Investigacion y de Estudios Avanzados del IPN, Mexico D.F. (Mexico)]. E-mail: dcmartinez@cinvestav.mx

    2009-09-15

    This work presents the synthesis of the binary compound PdAg and the electrochemical characterization for oxygen reduction reaction (ORR) in acid medium. The catalyst is obtained from the reduction of Pd(NO{sub 3}){sub 2}·2H{sub 2}O and AgNO{sub 3} with NaBH{sub 4} in THF. The synthesized compound was physically characterized with transmission electron microscopy (TEM), sweep electron microscopy (SEM) and x-ray diffraction (XRD) of powder. Electrochemical studies were conducted to determine the catalytic activity and intrinsic properties of the PdAg material for the ORR in acid medium using cyclic voltamperometry (CV), rotary disc electrode (RDE) and electrochemical impedance spectroscopy (EIS) in a solution of H{sub 2}SO{sub 4} 0.5 M at 25 degrees Celsius. The electrochemical current-potential responses were compared to those of palladium and platinum. The kinetic results showed an increase in the performance of the bimetallic electrocatalyst containing Ag as compared to pure Pd, but less than that obtained with nanometric Pt. The Tafel slopes obtained are roughly120 mV dec-1, similar to that reported for Pt and Pd and for other Ru-based electrocatalysts. [Spanish] En este trabajo se presentan la sintesis del compuesto binario PdAg y su caracterizacion electroquimica para la reaccion de reduccion de oxigeno (RRO) en medio acido. El catalizador se obtuvo a partir de la reduccion de Pd(NO{sub 3}){sub 2}·2H{sub 2}O y AgNO{sub 3} con NaBH{sub 4} en THF. El compuesto sintetizado se caracterizo fisicamente por microscopia electronica de transmision (MET), microscopia electronica de barrido (MEB) y difraccion de rayos X (DRX) de polvos. Se realizaron estudios electroquimicos para determinar la actividad catalitica y las propiedades intrinsecas del material de PdAg para la reaccion de reduccion de oxigeno (RRO) en medio acido, utilizando las tecnicas de voltamperometria ciclica (VC), electrodo disco rotatorio (EDR) y espectroscopia de impedancia electroquimica (EIE), en

  7. Synthesis and characterization of cobalt oxide and titanium mixtures using mechanical alloying and its response to oxygen reduction; Sintesis y caracterizacion de mezclas de oxidos de cobalto y titanio por aleado mecanico y su respuesta para la reduccion de oxigeno

    Energy Technology Data Exchange (ETDEWEB)

    Basurto S, R.; Bonifacio-Martinez, J.; Fernandez, S.M [Instituto Nacional de Investigaciones Nucleares, Ocoyoacac, Estado de Mexico (Mexico)]. E-mail: rafael.basurto@inin.gob.mx

    2009-09-15

    The synthesis of Co{sub 3}O{sub 4} and CoTiO{sub 3} oxides was conducted using mechanical alloying and combustion. Co{sub 3}O{sub 4} used was obtained using a SPEX ball mill with cobalt nitrate, Co(NO{sub 3})36H{sub 2}O plus urea, CH{sub 4}N{sub 2}O, in a molar ratio of 1:1 and a ball weight ratio of 1:4 with grinding times of 2.5 hours in an argon atmosphere. The material obtained after alloying underwent combustion at 400 degrees Celsius and 500 degrees Celsius, obtaining oxides of mixed cobalt valence. This material was mixed with TiO{sub 2} with a weight ratio of 1:1 and was mechanically alloyed with a ball weight ratio of 1:8; grinding was performed for 2.5 hours in argon atmosphere and it underwent combustion at 800 degrees Celsius. Characterization was performed using x-ray diffraction, low-vacuum sweep electron microscopy and EDS. The electrochemical performance was obtained in a galvanostat-potentiostat (Princenton Applied Research modelo 273). Both materials present electrocatalytic activity for oxygen reduction reaction in alkaline medium. [Spanish] La sintesis de los oxidos: Co{sub 3}O{sub 4} y CoTiO3 se realizo por la tecnica de aleado mecanico y combustion. El Co{sub 3}O{sub 4} utilizado, se obtuvo por con un molino de bolas SPEX, utilizando nitrato de cobalto, Co(NO{sub 3})36H{sub 2}O mas urea, CH{sub 4}N{sub 2}O, en una relacion molar 1:1.y una relacion en peso de bolas de 1:4 con tiempos de molienda de 2.5 horas, en atmosfera de argon, al termino del aleado el material obtenido se llevo a combustion a 400 grados centigrados y 500 grados centigrados, obteniendose el oxido de valencia mixta de cobalto. Este material se mezclo con TiO{sub 2}, en una relacion en peso de 1:1 y se aleo mecanicamente, con una relacion en peso de bolas de 1:8, por 2.5 horas de molienda en atmosfera de argon y llevandolo a combustion a 800 grados centigrados. La caracterizacion se hizo por: Difraccion de Rayos X, Microscopia Electronica de Barrido de Bajo Vacio y EDS El

  8. Arte en el espacio público como expresión de protesta política : Acciones sobre la despenalización del aborto por los colectivos Lanzallamas y Arte al Ataque de la ciudad de La Plata, Buenos Aires, Argentina

    OpenAIRE

    Fükelman, María Cristina; Ladaga, Silvia Andrea Cristian; Sánchez Pórfido, Elisabet

    2012-01-01

    Este trabajo se inscribe en los avances de la investigación, “Arte de acción en La Plata en el Siglo XXI. Registro e intervenciones artísticas”; acreditado por la Facultad de Bellas Artes, Secretaría de Ciencia y Técnica de la Universidad Nacional de La Plata, en el marco de Programas de Incentivos del Ministerio de Educación de la Nación. En este artículo se analizan las acciones de los colectivos Lanzallamas (conformado por estudiantes avanzados de la carrera de Sociología) y Arte al Ata...

  9. Biodiversidad de la flora del flanco oriental del Cordón del Plata (Luján de Cuyo, Mendoza, Argentina. Catálogo florístico Biodiversity of the flora of the eastern slope of the Cordón del Plata (Luján de Cuyo, Mendoza, Argentina

    Directory of Open Access Journals (Sweden)

    Eduardo Méndez

    2009-07-01

    Full Text Available La biodiversidad de la flora de la vertiente oriental del Cordón del Plata, Luján de Cuyo, Mendoza, Argentina se analizó a lo largo de un gradiente altitudinal, entre los 1200 y 4500 m s.n.m. Para ello se utilizó la lista florística de las especies de 89 comunidades vegetales distribuidas en 14 unidades de vegetación, 5 pisos de vegetación y 3 unidades fitogeográficas. Para cada especie se consideró su distribución en los grupos de comunidades vegetales, ubicación fitogeográfica, formas de vida, origen y registro de colección. La flora examinada contiene 667 especies vegetales que se corresponden con 338 géneros y 82 familias. Las familias están representadas por 8 Pteridophyta, 1 Gymnospermae y 73 Angiospermae, con 12 Monocotyledoneae y 61 Dicotyledoneae. Las familias mejor representadas son Asteraceae y Poaceae que tienen en conjunto 110 géneros y 249 especies. Los géneros Senecio, Baccharis y Adesmia son los más ricos en especies. Aproximadamente el 20 % de las especies son endémicas de Argentina. La flora del área se la compara con la del país, la provincia y la de otras áreas.Floristic catalogue. The floristic biodiversity of the eastern slope of the Cordón del Plata, Luján de Cuyo, Mendoza, Argentina, was studied along an altitudinal gradient, between 1200 and 4500 m a.s.l. For this we used a floristic list of 89 plant communities, distributed in 14 vegetation types, 5 vegetation belts and 3 phytogeographic units. For each of the species, its distribution in the groups of plant communities, phytogeographic position, life form, biogeographical origin, and registration of each collection was considered. The studied flora has 667 species, corresponding to 338 genera and 82 families. There are 8 Pteridophyta, 1 Gymnospermae, and 73 Angiospermae, of which 12 are Monocotyledons and 61 Dicotyledons. The most represented families are Asteraceae and Poaceae, which in total have 110 genera and 249 species. The most species

  10. Un perfil de vegetación entre La Plata (Huila y el Volcán del Puracé Un perfil de vegetación entre La Plata (Huila y el Volcán del Puracé

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    Rangel Ch. Orlando

    1986-06-01

    Full Text Available This contribution presents the plant-communities characterized in the trayect between La Plata (Huila and the crater of the Puracé volcano. The methodology followed in this study is that proposed in the Zurich-Montpellier school (BRAUN-BLANQUET, 1979. The profile of vegetation includs plant-communities of the jungle-type which are pluri-stratified on Ecuatorial and sub-Andean life zones and plantcommunities with a single stratification (upper Paramo belt. In the characterization of the plant-communities described was taken of the physiognomy (the structure as an expression of abiotic conditions.  Dates about plant-density in the arboreal stratum and preliminary characteristics of the soil in some of the places inventaried also are provided.En esta contribución se caracterizan las comunidades vegetales que se establecen en el trayecto entre La Plata (Huila y el cráter del volcán Puracé.  La metodología que se siguió es la de la escuela Zurich-Montpellier (BRAUN-BLANQUET, 1979. El perfil de vegetación incluye comunidades de tipo selvático pluriestratificadas, en las regiones de vida Ecuatorial y sub-Andina y comunidades uniestratificadas en la franja del super-páramo. Se colocó especial énfasis en el aspecto estructural (fisionomía de la vegetación y con base en los resultados obtenidos se recomiendan límites para la distribución de los estratos o arreglo en sentido vertical dentro de una fitocenosis determinada. Se suministran también datos sobre la densidad en los estratos altos y sobre las características preliminares de los suelos en algunos de los sitios muestreados.

  11. Desirable New Geologic Research in Support of Radioactive Waste Disposal as Indicated by Hanford Experience; Nouvelles Recherches Geologiques Souhaitables au Sujet de l'Elimination des Dechets Radioactifs, Selon les Indications Fournies par l'Experience de Hanford; 041f 0420 041e 0412 0415 0414 ; Nuevas Investigaciones Geologicas que Convendria Hacer para Facilitar la Evacuacion de Desechos Radiactivos Siguiendo las Indicaciones Proporcionadas por las Experiencias Efectuadas en Hanford

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Randall E. [Hanford Laboratories, Hanford Atomic Products Operation, General Electric Company, Richland, WA (United States)

    1960-07-01

    geologica del lugar de que se trate. No obstante, la evacuacion en ese medio no tiene caracter definitivo ya que ningun material es impermeable o inmune a los efectos de la Uxiviacion o de la corrosion cuando se consideran periodos de tiempo en terminos geologicos. Las experiencias realizadas en Hanford hacen intervenir un maximo de caracteristicas geologicas entre los puntos de evacuacion y el punto mas proximo en que las personas quedarian expuestas a las radiaciones, Este es el concepto que Simpson denomino concepto de demora y desintegracion. Entre los problemas que plantea la evacuacion de desechos en Hanford cabe mencionar los siguientes: 1) la inexactitud cuantitativa de los datos geologicos; 2) la ausencia de materiales isotopicos homogeneos en la composicion del subsuelo; 3) la determinacion cuantitativa del grado en que las caracteristicas geologicas e hidrologicas se apartan de los valores promedios, y 4) la determinacion y medicion de los parametros de interes para estas experiencias. Para ilustrar los mencionados extremos, el- autor cita algunos casos registrados en Hanford. Se han realizado perforaciones que representan en total 557 pozos y 33.000 m de profundidad, pero los datos obtenidos han de ser utilizados con cautela. Los ensayos normalizados destinados a comprobar el comportamiento de la capa acuifera tienen un valor limitado, ya que la permeabilidad del suelo perforado y la direccion de las corrientes se reducen a valores medios. Los estudios del intercambio ionico proporcionan valores cuantitativos directamente aprovechables que ayudan a interpretar las caracteristicas geologicas. Los estudios hidrologicos, combinados con el estudio de la quimica de los suelos y con los datos geologicos, permiten un control geologico del movimiento de las aguas, .logicamente explicable. La evacuacion de desechos radiactivos en el suelo no es ni una panacea universal ni un procedimiento que haya de inspirar temor. La combinacion de los datos proporcionados por los

  12. Estado nutricional y composición corporal de niños pobres residentes en barrios periféricos de La Plata, Argentina Nutritional status and body composition of poor children in the outlying neighborhoods of La Plata, Argentina

    Directory of Open Access Journals (Sweden)

    Evelia E. Oyhenart

    2007-09-01

    Full Text Available OBJETIVOS: Evaluar el estado nutricional y la composición corporal, como indicadores de la calidad de vida, en niños pobres que concurren a comedores comunitarios de La Plata, Argentina. MÉTODOS: Se realizó un estudio transversal entre abril y noviembre de 2004 con 608 niños y niñas sanos de 1 a 11 años de edad que asistían a dos comedores barriales ubicados en la periferia de la ciudad de La Plata, Argentina. La muestra se estratificó según la edad y el sexo de los participantes. Se determinó la talla para la edad, el peso para la edad y el peso para la talla, así como el índice de masa corporal, el área muscular y el área adiposa. Los datos se transformaron a puntuaciones z. Se calcularon la razón de posibilidades (odds ratio y sus respectivos intervalos de confianza de 95%. RESULTADOS: La prevalencia de peso bajo para la edad fue de 9,0%, la de peso bajo para la talla fue de 3,0% y la de talla baja para la edad de 15,0%. Las prevalencias de sobrepeso y obesidad fueron de 12,5% y 7,1%, respectivamente. En esta población, 47,2% presentó déficit de masa muscular y 20,4% tenía déficit de masa adiposa. En los niños con sobrepeso y obesidad, el área adiposa fue 34,3% mayor que la de la población de referencia; en contraste, el área muscular fue 12,5% menor. CONCLUSIONES: En las comunidades infantiles estudiadas coexisten la desnutrición y el sobrepeso. La elevada prevalencia de retraso en el crecimiento (talla baja para la edad y desnutrición global (peso bajo para la edad y la grave reducción de la masa muscular, aun en niños con sobrepeso u obesidad, parecen ser consecuencias de un proceso adaptativo inevitable frente a las condiciones adversas de vida.OBJECTIVES: To evaluate nutritional status and body composition as indicators of quality of life among poor children served by neighborhood soup kitchens in La Plata, Argentina. METHODS: From April to November 2004, we conducted a cross-sectional study of 608 healthy

  13. Autocyclic behaviour of alluvial and deltaic systems. Geologica Ultraiectina (306)

    NARCIS (Netherlands)

    van Dijk, M.|info:eu-repo/dai/nl/304833630

    2009-01-01

    Strata formation in sedimentary systems is the result of the interplay of controls generated within (autogenic) and outside (allogenic) the system. Allogenic controls include climate, sea level and tectonics. For example, tectonic tilting or sea-level variations can alter the space available for

  14. Reorganization of convergent plate boundaries. Geologica Ultraiectina (340)

    NARCIS (Netherlands)

    Baes, M.

    2011-01-01

    It is still unclear where a subduction is initiated and what are the responsible mechanisms involved in subduction initiation process. Understanding of subduction initiation will advance our knowledge of how and when plate tectonics started on Earth. Another issue concerning the subduction process

  15. XRD applied to the determination of pigments and composition of lithic materials and ceramics from archaeological pre-hispanic sites of the Rio de la Plata

    International Nuclear Information System (INIS)

    Beovide, Laura; Pardo, Helena; Faccio, Ricardo; Mombru, Alvaro; Piston, Mariela

    2011-01-01

    Full text: The earliest records of human occupation on the lower basin of Santa Lucia River are dated ca. 4800 14 C years BP, in the area of one of the major tributaries of the Rio de la Plata on the Uruguayan coast. These societies were basically hunters and gatherers until ca. 3000 14 C years BP when they incorporated the horticulture. In this multidisciplinary work, two cases of application of XRD analysis of archaeological materials are presented to provide new perspectives in solving various problems related to the technological organization of these societies. In the first case, ceramics and pigments from an archaeological context prior to the hispanic-indian contact were analyzed. The X-ray powder diffraction patterns were obtained using a RIGAKU, Ultima IV with CBO monochromator, CuK α radiation was at 40 kV and 20 mA tube power at 0.02 deg/seg, operating in the range from 2θ=5.00 to 60.00 deg. According the comparison between the experimental recorded X-ray diffraction pattern to those stored in a X-ray powder diffraction database reveals that the piece of pottery is mainly constitute of quartz (SiO 2 ) and hematite (Fe 2 O 3 ) while the mineral sample is probably composed mainly of quartz (SiO 2 ) and goethite (FeO 3 .H 2 O). The results allow a first approximation to know the inorganic pigments that were part of the decoration of the pottery and pigments used in the archaeological context. In the second case an amphibolite instrument from ca. 2700 14 C years BP related to a shell midden was analyzed and compared with amphibolites located 15 km of the archaeological site to assess if they were the raw materials for these instruments. Compositional XRD mineralogical analysis shows that the both samples seem to have similar mineral composition, which is mainly quartz (SiO 2 ) and a mixed sodium magnesium and calcium silicate (NaCa 2 (Mg 4 Ti)Si 6 Al 2 O 23 (OH) 2 ). This suggests that most likely the source of supply for the amphibolites instruments come

  16. XRD applied to the determination of pigments and composition of lithic materials and ceramics from archaeological pre-hispanic sites of the Rio de la Plata

    Energy Technology Data Exchange (ETDEWEB)

    Beovide, Laura [Department of Archeology, National Museum of Anthropology, Montevideo, (Uruguay); Pardo, Helena; Faccio, Ricardo; Mombru, Alvaro [Centro NanoMat, Polo Tecnologico de Pando, Facultad de Quimica, Universidad de la Republica, Pando, Canelones (Uruguay); Crystallography, Solid State and Materials Laboratory (Cryssmat-Lab), DETEMA, Facultad de Quimica, Universidad de la Republica, Gral, Montevideo (Uruguay); Piston, Mariela, E-mail: mpiston@fq.edu.u [Analytical Chemistry, Estrella Campos Department, Facultad de Quimica, Universidad de la Republica, Montevideo (Uruguay)

    2011-07-01

    Full text: The earliest records of human occupation on the lower basin of Santa Lucia River are dated ca. 4800 {sup 14}C years BP, in the area of one of the major tributaries of the Rio de la Plata on the Uruguayan coast. These societies were basically hunters and gatherers until ca. 3000 {sup 14}C years BP when they incorporated the horticulture. In this multidisciplinary work, two cases of application of XRD analysis of archaeological materials are presented to provide new perspectives in solving various problems related to the technological organization of these societies. In the first case, ceramics and pigments from an archaeological context prior to the hispanic-indian contact were analyzed. The X-ray powder diffraction patterns were obtained using a RIGAKU, Ultima IV with CBO monochromator, CuK{sub {alpha}} radiation was at 40 kV and 20 mA tube power at 0.02 deg/seg, operating in the range from 2{theta}=5.00 to 60.00 deg. According the comparison between the experimental recorded X-ray diffraction pattern to those stored in a X-ray powder diffraction database reveals that the piece of pottery is mainly constitute of quartz (SiO{sub 2}) and hematite (Fe{sub 2}O{sub 3}) while the mineral sample is probably composed mainly of quartz (SiO{sub 2}) and goethite (FeO{sub 3}.H{sub 2}O). The results allow a first approximation to know the inorganic pigments that were part of the decoration of the pottery and pigments used in the archaeological context. In the second case an amphibolite instrument from ca. 2700 {sup 14}C years BP related to a shell midden was analyzed and compared with amphibolites located 15 km of the archaeological site to assess if they were the raw materials for these instruments. Compositional XRD mineralogical analysis shows that the both samples seem to have similar mineral composition, which is mainly quartz (SiO{sub 2}) and a mixed sodium magnesium and calcium silicate (NaCa{sub 2}(Mg{sub 4}Ti)Si{sub 6}Al{sub 2}O{sub 23}(OH){sub 2}). This

  17. Variability in terrigenous sediment supply offshore of the Rio de la Plata (Uruguay) recording the continental climatic history over the past 1200 years

    Science.gov (United States)

    Perez, L.; García-Rodríguez, F.; Hanebuth, T. J. J.

    2015-04-01

    The continental shelf adjacent to the Río de la Plata (RdlP) exhibits extremely complex hydrographic and ecological characteristics which are of great socio-economic importance. Since the long-term environmental variations related to the atmospheric (wind fields), hydrologic (freshwater plume), and oceanographic (currents and fronts) regimes are little known, the aim of this study is to reconstruct the changes in the terrigenous input into the inner continental shelf during the Late Holocene period (associated with the RdlP sediment discharge) and to unravel the climatic forcing mechanisms behind them. To achieve this, we retrieved a 10 m long sediment core from the RdlP mud depocenter at a depth of 57 m (GeoB 13813-4). The radiocarbon age control indicated an extremely high sedimentation rate of 0.8 cm per year, encompassing the past 1200 years (750-2000 AD). We used element ratios (Ti / Ca, Fe / Ca, Ti / Al, Fe / K) as regional proxies for the fluvial input signal, and the variations in relative abundance of salinity-indicative diatom groups (freshwater vs. marine-brackish) to assess the variability in terrigenous water and sediment discharge. Ti / Ca, Fe / Ca, Ti / Al, Fe / K and the freshwater diatom group showed the lowest values between 850 and 1300 AD, while the highest values occurred between 1300 and 1850 AD. The variations in the sedimentary record can be attributed to such regional and global climatic episodes as the Medieval Climatic Anomaly (MCA) and the Little Ice Age (LIA), both of which had a significant impact on rainfall and wind patterns over the region. During the MCA, a northward migration of the Intertropical Confluence Zone (ITCZ) could explain the lowest element ratios (indicative of a lower terrigenous input) and a marine-dominated diatom record, both indicative of a reduced RdlP freshwater plume. In contrast during the LIA, the southward migration of the ITCZ accompanied by El Niño-like state conditions may have led to an expansion of

  18. Hydrogeochemistry and pollution effects of an aquifer in Quaternary loess like sediments in the landflling area of Mar del Plata, Argentina

    Directory of Open Access Journals (Sweden)

    Daniel E. Martínez

    2013-01-01

    Full Text Available Sedimentos de tipo loéssico cubren una superficie aproximada de 1.800.000 km2 en la llanura Pampeana de Argentina, formando un sistema acuífero que es utilizado para abastecimiento de agua a ciudades y la población rural en la región. Este sistema acuífero suministra el agua que sustenta las actividades productivas que contribuyen en un 60% al producto bruto nacional. Es este trabajo se realiza un estudio detallado en un sector del acuífero próximo a la ciudad de Mar del Plata, provincia de Buenos Aires, en el que se localizan tres rellenos sanitarios. El principal objetivo es caracterizar los procesos geoquímicos que dan origen a la composición observada del agua subterránea. Se perforaron cinco pozos para la toma de muestras de agua y sedimentos, y evaluar el impacto de la infiltración del lixiviado sobre esos procesos. Se determinó la composición textural y mineralógica de los sedimentos y la composición química del agua. Las relaciones de equilibrio entre la fase sólida y la solución se determinó utilizando programas específicos. Se concluye que la composición química observada en la aguas es consecuencia principalmente de procesos de equilibrio con calcita e intercambio catiónico con adsorción de calcio y liberación de sodio. La disolución de minerales de sílice amorfo, y la hidrólisis de silicatos en forma subordinada, da origen a altas concentraciones de sílice en las aguas. La mezcla con la infiltración del lixiviado incrementa las concentraciones de los iones conservativos cloruro y nitrato, pero no se modifican en general los procesos hidrogeoquímicos mayoritarios.

  19. U-Pb age constraints for the La Tuna Granite and Montevideo Formation (Paleoproterozoic, Uruguay): Unravelling the structure of the Río de la Plata Craton

    Science.gov (United States)

    Pamoukaghlián, Karina; Gaucher, Claudio; Frei, Robert; Poiré, Daniel G.; Chemale, Farid; Frei, Dirk; Will, Thomas M.

    2017-11-01

    The Río de la Plata Craton is a continental block that crops out in Uruguay, eastern Argentina, southernmost Brazil and Paraguay. It comprises in Uruguay the Piedra Alta, Tandilia and Nico Pérez terranes, separated by the Colonia and the Sarandí del Yí megashears. The La Tuna Granite, which intrudes the Araminda metasandstones in the Tandilia Terrane, was considered Cambrian in age and the intruded sandstones were assigned to the Neoproterozoic Piedras de Afilar Formation. We show that the granite is Paleoproterozoic in age and that the host metasandstones do not belong to the Piedras de Afilar Formation, but to the Paleoproterozoic Montevideo Formation. U-Pb LA ICP-MS of zircon ages for the La Tuna Granite yielded a concordant crystallization age of 2156 ± 26 Ma. Furthermore a metamorphic event at 2010 ± 9 Ma is revealed by Pb stepwise leaching dating of monazites. U-Pb detrital zircon ages of the host Araminda metasandstone yield an upper intercept discordia age of 2152 ± 29 Ma, which marks the intrusion of the La Tuna pluton, and which is in accordance with the zircon U-Pb LA ICP MS constraints. A concordant U-Pb detrital zircon age of 2465 ± 40 Ma provides a maximum depositional age constraint for the metapsammites. Comparing quartz arenites of the Ediacaran Piedras de Afilar Formation with the Araminda metaquartzites, we conclude that they are very similar regarding petrology but they differ in age and metamorphic overprint. Detrital zircons in quartz arenites of the Piedras de Afilar Formation show youngest ages of 1.0 Ga. On the other hand, detrital zircons recovered from the Araminda metasandstones and the age of the intruding granite allow interpreting a depositional age between 2465 and 2150 Ma. Nd model ages show crustal residence times in average more than 200 myr older for the Tandilia Terrane both in Uruguay and Argentina, with a significant Neoarchean component, which is lacking in the Piedra Alta Terrane. Whereas the Piedra Alta Terrane was

  20. Short-term responses to sewage discharge and storms of subtidal sand-bottom macrozoobenthic assemblages off Mar del Plata City, Argentina (SW Atlantic)

    Science.gov (United States)

    Elías, R.; Palacios, J. R.; Rivero, M. S.; Vallarino, E. A.

    2005-04-01

    This work describes short-term responses of sandy-bottom infaunal macrobenthic communities to environmental disturbances, such as episodic storms and the intertidal sewage discharge of the Mar del Plata City (38° S, 57° W, Argentina). Sewage discharge increases by up to 60% every summer due to tourism pressure. Episodic storms affect the area during autumn-winter and arguably have a cleaning effect on the water and sediment quality. Quantitative data on benthic communities (based on Van Veen grab samples), water and sediment variables were obtained in November 1999 and March 2000. During March the sampling was carried out before and after a storm. Parametric and non- parametric tests showed highly significant differences in both environmental (pH, dissolved oxygen, salinity, temperature, grain size and total organic carbon of sediments) and biological data (species distribution and abundances, density, species number, diversity and evenness), reflecting changes that might be related to increasing sewage discharge between November and March, and to storm effects of March. High values of pH and dissolved oxygen, including a slight stratification in the water column, as well as high values of mean grain size and total organic carbon were observed in March with the increasing sewage volume. Nevertheless, diversity and evenness showed low values, but higher density. The ratio crustacean/polychaetes + molluscs also showed low values compared to November data. Maldanid polychaetes (indicator of low content of organic matter in sediments) dominated in November, but they were replaced by the polychaete Prionospio spp. (indicator of organic enrichment in subtidal areas) and the tanaidacean Kalliapseudes schubarti in March. Before the storm event, values of both environmental and biological data returned to relatively normal conditions, but without reaching the November values, reflecting the disturbance produced by a moderate northern storm. In spite of an inappropriate

  1. Concentración de pesticidas organoclorados en aire del sur de la cuenca del Plata: un año de muestreo

    Directory of Open Access Journals (Sweden)

    Malena Astoviza

    2014-01-01

    Full Text Available Con el objeto de estudiar la concentración y distribución de plaguicidas organoclorados (POCLs en aire del sur de la cuenca del Plata se instalaron muestreadores pasivos de espuma de poliuretano (n=20 recolectados cada 3-4 meses durante un año.La concentración media anual de POCLs osciló entre 326 y 9000 pg/m3 con predominancia de endosulfanos (Endo  (40-98% del total. Los promedios anuales de Endo (230-8936 pg/m3  son superiors a los reportados para otros paises de la región  (Brasil, Bolivia, Chile y Colombia: 114-898 pg/m3. Los valores máximos alcanzados corresponden al período cálido, en zonas de mayor actividad sojera: Norte de Bs As y Sur de E.Ríos y Santa Fe (3072-21521 pg/m3.Las concentraciones de DDTs (12-235 pg/m3 resultan un orden de magnitud inferiores a las de sitios en los que se utiliza para combatir la malaria (India: 5356 pg/m3; sur de México: 2360 pg/m3 pero la relación DDT/DDE (1.1-6.8 > 1 encontrada sugiere un aporte relativamente fresco, posiblemente debido al uso de Dicofol que presenta residuos de este compuesto.Los HCHs presentaron una alta concentración en Zárate (801-8348 pg/m3 donde resultaron predominantes (66% del total con una relación ?/?HCHs ?7, similar a la de la mezcla técnica sugiriendo un aporte fresco.En la zona metropolitana se destacaron los clordanos (83-691 pg/m3 que representan 5-45% del total, especialmente en la Capital Federal, donde la relación trans/cis-clordano>>1,6 indica un aporte fresco.Se concluye que los POCLs presentan diferencias en su distribución espacial; alta concentración de endosulfanos en zona agrícola; heterogeneidad de pesticidas  y mayor concentración de clordanos en zonas urbanas. Los valores de las concentraciones  y de relaciones entre compuestos sugieren aportes frescos clandestinos, o transporte a gran escala.

  2. Technical feasibility of using silver and copper ions electro generated in the microbiological control of cooling systems; Factibilidad tecnica para emplear iones plata y cobre electrogenerados en el control microbiologico de los sistemas de enfriamiento

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Susana M; Martinez Meza, Esteban; Alvarez Gallegos, Alberto [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    2001-07-01

    bacterial populations promoters of the microbiological influenced corrosion and the biological fouling at levels of 1000 c/ml and less, competing with the conventional cooling water treatment processes. Also, the adherence capacity of the biofilm on the surfaces of the cooling system would be seriously affected because the silver is adsorbed to the surface that contains it and still continues its bactericidal effect. Additionally, the coliform bacteria are reduced below the levels accepted by the Mexican Official Standard. A table of the silver required for disinfection of different water qualities is shown and another one on the evaluation of the process and finally one on the effectiveness of the process using the silver/copper system in residual water. [Spanish] El objetivo de este trabajo es determinar la factibilidad tecnica de sustituir el uso de cloro por otro biocida (ionizacion de plata o cobre) no peligroso en aguas de enfriamiento. Esta tecnica de ionizacion podria ser empleada para tratar el agua de procesos industriales en general. El agua empleada provino del agua de repuesto del sistema de enfriamiento de la Central Termoelectrica de Valle de Mexico (CTEVM) y agua residual de las plantas de tratamiento del Instituto Mexicano de Tecnologia del Agua (IMTA) y el Instituto de Investigaciones Electricas (IIE). Los tres tipos de agua empleados tienen caracteristicas fisicas, quimicas y biologicas similares. La metodologia usada fue la prueba de jarras y por sistema continuo. Se indica el analisis bacteriologico llegando a la conclusion. Los sistemas metalicos estudiados en el establecimiento del control microbiologico en el agua residual y agua de repuesto son plata, plata/cobre y cobre en los intervalos de concentracion de 200 mg/L a 3000 mg/L de plata y de 200 mg/L a 1200 mg/L de cobre. Los experimentos realizados en la prueba de jarras (sistema cerrado) se llevaron a cabo a dos temperaturas (25 {+-} 0.5 y 32 {+-} 0.5 ) sin controlar el pH; mientras que en el

  3. Aislamiento de Escherichia coli productor de toxina Shiga durante un brote de gastroenteritis en un Jardín Maternal de la Ciudad de Mar del Plata Isolation of Shiga toxin-producing Escherichia coli strains during a gastrointestinal outbreak at a day care center in Mar del Plata City

    Directory of Open Access Journals (Sweden)

    D. Gomez

    2005-12-01

    Full Text Available Entre el 15 de octubre y el 8 de noviembre de 2003 ocurrió un brote de gastroenteritis en un Jardín Maternal de un Hospital de la ciudad de Mar del Plata. Catorce de un total de 80 niños (17,5%, edad promedio 23,6 ± 13,9 meses, presentaron diarrea, y un caso evolucionó a síndrome urémico hemolítico. La madre de uno de los afectados presentó diarrea simultáneamente. No se pudo establecer el origen del brote, pero probablemente la transmisión haya sido fundamentalmente persona a persona. Las prácticas habituales en el lactario del jardín maternal, y las condiciones inadecuadas de infraestructura y hábitos de higiene de la cocina del Hospital fueron señalados como factores de riesgo. En un caso se detectó Escherichia coli productor de toxina Shiga (STEC O103:H2, y STEC O26:H11 en otro. En el niño infectado por STEC O26:H11, la excreción se extendió por un período de 37 días. La no detección de STEC en aquellos casos en los cuales el intervalo entre el inicio de los síntomas y la toma de muestra fue mayor a 6 días, enfatiza la necesidad de la recolección temprana de especímenes. Las principales conclusiones de este estudio fueron la necesidad de establecer normas óptimas de higiene, informar rápidamente la ocurrencia de casos de gastroenteritis y confirmar la negativización de la excreción del patógeno.From October 15 to November 8, 2003, a gastrointestinal outbreak occurred at a day care center in a Hospital in Mar del Plata City. Fourteen out of 80 (17.5% children, mean age 23.6 ± 13.9 months, and the mother of one of them had diarrhea. One case developed hemolytic uremic syndrome. No conclusive evidence of the origin of the outbreak was found, but the epidemic curve suggested person-to-person spread. The usual practices at the place where infant milk formula was prepared at the day care center, together with the inadequate infrastructure conditions and hygiene practices at the kitchen of the hospital, were

  4. From fresh water to the slope: fish community ecology in the Río de la Plata and the sea beyond Desde el agua dulce hasta el talud: ecología de comunidades de peces en el Río de la Plata y el mar adyacente

    Directory of Open Access Journals (Sweden)

    Mirta L García

    2010-01-01

    Full Text Available The spatial pattern of fish assemblages and its relationship with factors along an environment gradient, from fresh to marine water environment along the Río de la Plata estuary (36ºS, 56ºW the shelf and part of the slope, was examined using data from 22 sampling stations. Fish were sampled from all station with an Engel type trawl (200 mm stretched mesh in the wings, 120 mm stretched mesh in the cod ends, 4 m vertical opening and 15 m horizontal aperture towed at 4 knots for 20 to 30 min per set. Cluster analysis and ordination analysis MDS were used to define spatial distribution of fish assemblages based on fish composition (abundance and biomass. BIO-ENV process was used to estimate assemblage association with depth, temperature and salinity of surface and bottom waters. The results of these analyses showed that the fish community along the riverine-marine gradient was structured in four assemblages: riverine, estuarine, shelf and slope. These assemblages were found to differ significantly in their species composition. Each assemblage was characterized by several common and discriminator species and characterized by differing environmental conditions. Bottom salinity and bottom temperature were the environmental variables most strongly associated with differences in assemblage structure across the various areas. The changes in assemblage structure between areas were gradual, with no sharp boundaries.Se analizó el patrón espacial de las asociaciones de peces y su relación con los factores ambientales a lo largo del gradiente desde el agua dulce en el Río de la Plata hasta la parte superior del talud. Los peces fueron muestreados en 22 estaciones con una red de arrastre de fondo tipo Engel (200 mm de abertura de malla en las alas, 120 en el copo, 4 m de abertura vertical y 15 m de abertura horizontal con una velocidad de arrastre de 4 nudos durante 20 a 30 min. Para definir la distribución espacial de las asociaciones de peces basadas

  5. First record of the invasive medusa Blackfordia virginica (Hydrozoa: Leptomedusae in the Río de la Plata estuary, Argentina-Uruguay Primer registro de la medusa invasora Blackfordia virginica (Hydrozoa: Leptomedusae en el estuario del Río de la Plata, Argentina-Uruguay

    Directory of Open Access Journals (Sweden)

    GABRIEL GENZANO

    2006-06-01

    Full Text Available Blackfordia virginica is a well-known invasive medusa inhabiting estuarine areas. It was recently detected in northern Argentina, constituting the first record of invasive hydromedusa for the Argentine Sea. In this work more than 1,500 plankton samples in the southwestern Atlantic Ocean (34-55º S from 1983 to 2000 were analyzed. More than 5,000 specimens per sample of B. virginica were found in Río de la Plata estuary for the first time in February 2000. This river is one of the large waterways of South America with an intense nautical traffic and several exotic species has been recorded here, mainly due to trans-oceanic shipping traffic. It is important to point out that we found medusae of both sexes (therefore this species could be introduced in either the medusa or the polyp stages or both, different size classes (including very small juveniles and maturation stages, and in such high numbers that would suggest local reproduction. For this reason the recent finding of this hydromedusa could represent the starting point of an successful introductionBlackfordia virginica es una medusa invasora reconocida por habitar áreas estuariales. Recientemente fue descubierta en el norte de Argentina, constituyendo el primer registro de una hidromedusa invasora para el mar argentino. En este trabajo se analizaron más de 1.500 muestras de plancton en el Océano Atlántico sudoccidental (34-55º S desde 1983 hasta el año 2000. Más de 5.000 especímenes por muestra fueron encontrados por primera vez en el estuario del Río de la Plata durante febrero del año 2000. Este río es una de las mayores vías de agua de América del Sur, posee un intenso tráfico náutico y varias especies exóticas se han registrado allí, principalmente debido al tráfico marítimo transoceánico. Es importante señalar que se encontraron medusas de ambos sexos (por lo tanto esta especie podría haber sido introducida en su estadio medusa, pólipo o ambos, con diferentes

  6. Alfabetización en Astronomía de docentes de Educación Primaria y de Educación Secundaria en La Plata

    Science.gov (United States)

    De Biasi, M. S.; Orellana, R. B.

    2014-10-01

    La educación de este siglo tiene como uno de sus retos alcanzar la alfabetización cientfica de todos los ciudadanos para que comprendan y tomen decisiones sobre el mundo natural y sus cambios originados por la actividad humana utilizando el conocimiento científico. En esta misión los docentes de los niveles obligatorios de enseñanza juegan un papel clave por su rol de agentes multiplicadores del conocimiento. Se requiere, entonces de una adecuada alfabetización en ciencias de los docentes o, como mínimo, que dominen los temas científicos a enseñar. En el campo de la Astronomía, numerosas investigaciones han señalado que maestros de primaria y estudiantes de profesorados poseen una escasa formación en estos temas (Camino 1995 y 1999, Gangui 2010), que frecuentemente presentan a los alumnos concepciones alternativas o no científicas de los fenómenos astronómicos cotidianos (Kriner 2004, Vega Navarro 2007, Gangui et al 2010); a lo que se suma la presentación confusa o errónea de algunos temas astronómicos en los textos escolares (Kriner 2004). Desde 2011, la Facultad de Ciencias Astronómicas y Geofísicas, UNLP, ofrece un curso de capacitación destinado a fortalecer y actualizar los contenidos académicos y didácticos de los docentes del distrito La Plata utilizando diversas estrategias didácticas. Los contenidos comprenden los temas astronómicos de los diseños curriculares vigentes. La evaluación diagnóstica de los conocimientos previos de los docentes cursantes sobre los contenidos de mayor presencia en los diseños curriculares mostró resultados similares a las investigaciones arriba mencionadas. Referente a los movimientos de la Tierra, en promedio, el 54% poseía conceptos erróneos y el 16% no los sabía; con referencia a la Luna el 56% poseía conceptos erróneos y un 4% no los sabía. Los resultados del curso mostraron que el 95% de los docentes revirtió sus conceptos previos erróneos, que adquirió criterios para la búsqueda de

  7. Producción, evolución económica y análisis decimal. Un Estudio sobre el Río de la Plata en el siglo XVIII

    Directory of Open Access Journals (Sweden)

    Guerrero Soriano, Cándido P.

    1994-06-01

    Full Text Available Not available.

    En el siglo XVIII, el Río de la Plata se vio afectado de forma clara y contundente por la política ilustrada y racionalista de la nueva casa reinante en la metrópoli. En parte por esa acción política, y sobre todo por la fuerza de los acontecimientos, se produjeron cambios, claramente perceptibles a grandes rasgos, pero difícilmente detectables y evaluables de forma concreta. Este trabajo pretende acercarse a la realidad menos visible mediante el análisis y la interpretación de datos cruzados de fuentes de índole diversa; a saber: fuentes decimales y registros fiscales.

  8. Producción y uso de ornamentos en las tierras bajas de Sudamérica: el caso de las poblaciones humanas prehispánicas del extremo meridional de la cuenca del Plata (Argentina

    Directory of Open Access Journals (Sweden)

    Acosta, A.A., Buc, N., Davrieux, M.N.

    2015-01-01

    Full Text Available En este trabajo se analizan los conjuntos ornamentales generados por las poblaciones humanas prehispánicas que ocuparon el extremo meridional de la cuenca del Plata. Se describen las piezas recuperadas en diversos sitios arqueológicos teniendo en cuenta las materias primas empleadas, sus mecanismos de obtención y otros aspectos relacionados con la manufactura. Posteriormente se evalúa y discute su potencial uso como medios de transmisión de información. Para ello se consideran diferentes factores vinculados con los sistemas de intercambio y la extensión de las redes sociales en el marco del crecimiento demográfico y del grado de complejidad social que alcanzaron dichas poblaciones durante la fase final del Holoceno tardío.

  9. David Ziziemsky y el ingreso del psicoanálisis francés en el hospital de niños Sor María Ludovica de la ciudad de La Plata

    OpenAIRE

    Freston, Emilia; Iveninato, Silvina; Vallejo, Emiliano; Riva, Alicia

    2011-01-01

    El presente trabajo forma parte de un proyecto de investigación más amplio cuyo fin es delimitar el contexto de recepción del psicoanálisis francés en la ciudad de La Plata en el período que se extiende desde 1966 hasta 1976. El concepto de recepción, supone que la lectura de una obra no consiste en una mera asimilación pasiva sino en un proceso que, concebido desde una perspectiva dialéctica, pone en juego una selección que realiza el lector en tanto se ve implicado su propio punto de vista....

  10. El precio de la fidelidad : La guerra de Sucesión en el Río de la Plata, los intereses locales y el bando Borbón

    OpenAIRE

    Jumar, Fernando Alberto; Molinié, A.; Merle, A.

    2004-01-01

    La guerra, como lo subraya Fernand Braudel, siempre pone en movimiento las flrees enproflndeur que son las economías, los Estados, las civilizaciones. Como este mismo autor constata, después de la batalla de Lepanto el escenario de la guerra pasa del Mediterráneo «au Nord, a l'Ouest sur I'Atlantique - et pour des siecles -la où elle doit etre, la oú bat le coeur du monde». Y en el extremo sur del Atlántico ocupado por los europeos en los tiempos modernos, está el Río de la Plata, y la guerra ...

  11. Scientific investigation for the integrated environmental administration of shared aquatic spaces, the challenge is to pass from the words to the facts: the case of the Rio de la Plata and its marine front (RPFM)

    International Nuclear Information System (INIS)

    Cantera Kintz, Jaime Ricardo

    2005-01-01

    The environmental management of Tran-boundary water bodies presents several limitations, ranging from the complex geographical and environmental contexts to differences in jurisdiction and governance, and also involving the interdisciplinary topics included in the integrated environmental management. Any program of environmental planning mainly needs of scientific research made in a close coordination and cooperation, since underestimated aspects cause management weakness. This paper describes the contexts in which the Argentinean-Uruguayan Binational Project Environmental Protection of the Rio de la Plata and its Maritime Front (RPFM) is developed, the main tools to build the scientific knowledge, and the strategies followed to implement a cooperative framework with the participation of environmental management and research institutions of both countries in the pursue of Project objectives

  12. Producción de plata y comercio en oruro a fines del período colonial. Análisis a través de las fuentes fiscales

    Directory of Open Access Journals (Sweden)

    Gavira Márquez, María Concepción

    2001-08-01

    Full Text Available This article analyzes the relation between silver production and the internal market in the mining region of Oruro at the end of the 18th century. On the basis of different complementary sources, including fiscal accounts, a hypothesis is presented to explain the problem posed by an increase in values from alcabalas during a period of mining crisis.

    En este trabajo se analiza la relación entre la producción de plata y el mercado interior en la región minera de Oruro a fines del siglo XVIII. Partiendo del estudio de diferentes fuentes complementarias, entre ellas las fiscales, se pretende explicar la problemática que plantea una subida de las alcabalas en un período de crisis minera.

  13. Afrontamiento activo y adaptación al envejecimiento en mujeres de la Ciudad de Mar del Plata: una revisión de la estrategia de autodistracción

    Directory of Open Access Journals (Sweden)

    Deisy Krzemien

    2005-01-01

    Full Text Available El presente trabajo propone, a partir de datos empíricos obtenidos en un grupo de adultas mayores, una reconceptualización de las estrategias de afrontamiento evitativas, especialmente la autodistracción, destacando su valor adaptativo frente a la crisis vital que genera el proceso de envejecimiento en las mujeres. Clínicos e investigadores sugieren que el envejecimiento implica una crisis del desarrollo que afecta la adaptación vital. La literatura científica considera que existe relación entre estrategias de afrontamiento y adaptación a situaciones críticas. Mediante un diseño cuasi-experimental de tipo pretest- postest con grupo control, se evaluaron las estrategias de afrontamiento antes y después de un programa de aprendizaje social, en una muestra de sesenta mujeres ancianas, de las cuales, treinta participaron de un curso de aprendizaje social en la Universidad de Adultos Mayores de la Universidad Nacional de Mar del Plata (Mar del Plata - Argentina, y treinta no lo hicieron. Se realizó un análisis comparativo y cuantitativo de los datos. Los resultados evidencian que las mujeres que participaron del programa de aprendizaje social presentan un estilo de afrontamiento activo y adaptativo y a la vez, un uso significativo de la estrategia de autodistracción, caracterizada teóricamente como evitativa y no adaptativa. Los resultados permiten elaborar una comprensión alternativa de la estrategia de autodistracción en función del afrontamiento a los sucesos críticos de la vejez. Se propone que frente a situaciones que no constituyen un problema a resolver como el proceso de envejecimiento en particular, la autodistracción debería considerarse como una estrategia de afrontamiento que promueve una adaptación efectiva.

  14. What is left behind when the lights go off? Comparing the abundance and composition of litter in urban areas with different intensity of nightlife use in Mar del Plata, Argentina.

    Science.gov (United States)

    Becherucci, Maria Eugenia; Seco Pon, Juan Pablo

    2014-08-01

    Nightlife activities represents an important source of urban litter; the latter often being left behind or abandoned in public places and streets. Mar del Plata is a very important city on the Atlantic coast of Argentina and is the main tourism destination in the South Atlantic region of South America. However, few studies on urban litter related to nightlife activities have been conducted in the area. Here we assessed (i) the abundance and composition of litter, and (ii) the spatial and temporal variations of its abundance, diversity, richness and evenness in urbanized areas with different intensity of nightlife activities from April 2008 to March 2009. An overall of 13,503 items were counted. Around 92% of the total litter was comprised by cigarette butts, papers and plastics. We found significant spatial differences in the abundance of litter between sampling sites, with the greatest amounts of litter at the Alem site followed by the Hipólito site (both with an intensive nightlife activity) compared with the Chauvin site (a quiet high-income neighborhood). The composition of litter of the Alem and the Hipólito sites was relatively similar and both sites differ with respect to the Chauvin site. Cigarette butts, papers, and plastics were the items that contributed most to the dissimilarity between sampling sites. The diversity of litter was the single community parameter that significantly differed from the other seasons. We discussed the potential effect of nightlife activities on the amounts and quality of urban litter in the city of Mar del Plata. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. La cuestión tecnológica en los planes de estudio de la Carrera de Bibliotecología de la Universidad Nacional de La Plata: aproximaciones críticas desde los documentos y la mirada de los actores The technology question through the curriculum of the Library Degree at the National University of La Plata: critical approaches from the documents and the perspectives of the actors

    Directory of Open Access Journals (Sweden)

    Claudia Nora Laudano

    2011-06-01

    Full Text Available Este trabajo indaga los modos de abordaje de la cuestión tecnológica en la formación profesional universitaria en Bibliotecología desde una mirada histórica que abarca 30 años. El estudio toma por caso la Carrera de Bibliotecología de la Facultad de Humanidades y Ciencias de la Educación de la Universidad Nacional de La Plata (Argentina y considera centrales las transformaciones curriculares en el área de tecnología. Para el abordaje metodológico se contempló, por una parte, el análisis documental de los planes de estudios, los programas de algunas asignaturas y otros materiales significativos. Por otra parte, se entrevistaron docentes que intervinieron en las modificaciones del currículo en los últimos 30 años. Del análisis de ambos materiales surgen tendencias coincidentes respecto del lugar de lo tecnológico en la formación profesional así como sugerencias acerca de posibles modificaciones en la enseñanza.This paper inquires how the technological question is approached in the university professional training in librarianship, in an historical overview which covers 30 years. It is a case study of the librarianship degree in the Facultad de Humanidades y Ciencias de la Educación de la Universidad Nacional de La Plata and the curricular transformations in the technological area are of key importance. The methodological approach is focused in the documental analysis of the curricula, the programs of some subjects and other significant materials. Also, some teachers responsible of the changes in the curriculum during the last 30 years were interviewed. From the analysis of both materials is possible to deduce coincident tendencies about the technology place in the professional training, as well as suggestions about possible modifications in the teaching of librarianship.

  16. Sorption Regularities in Behaviour of Fission-Product Elements during Filtration of their Solutions through Ground; Lois de l'Absorption des Elements Radioactifs Lors du Filtrage des Solutions a Travers les Terrains; 0417 0410 041a 041e 041d 0414 ; Leyes de la Absorcion de los Elementos Radiactivos Cuando se Filtran Soluciones a Traves de las Formaciones Geologicas

    Energy Technology Data Exchange (ETDEWEB)

    Spitsyn, V. I.; Balukova, V. D.; Gromov, V. V.; Zakharov, S. I.; Zhagin, B. P.; Spiridonov, F. M.

    1960-07-01

    cuatro meses. Despues, mediante una serie de perforaciones consecutivas, se extrajeron muestras de tierra recogidas a distintas profundidades y se analizaron para determinar su contenido de elementos radiactivos. Se pudo comprobar que la difusion de los radioisotopos alcanzaba una profundidad de diez metros por lo menos y que habia dos zonas perfectamente delimitadas en las que la radiactividad del terreno era menor: la capa superficial y el fondo de la zona de filtracion. Tambien se ha estudiado la absorcion del radioestroncio por los absorbentes naturales, especialmente por los minerales puros muy difundidos por las diversas formaciones geologicas. La presencia de iones de calcio, incluso en pequena cantidad, reduce considerablemente el grado de absorcion del radioestroncio. Sin embargo, segun su composicion -siempre que las demas condiciones sean iguales - otras sustancias pueden absorber el estroncio en cantidades mas elevadas que el calcio. Verificando in situ la absorcion y la migracion del radioestroncio se ha podido comprobar que la filtracion de las soluciones radiactivas puede revestir dos formas diferentes. En el primer caso, si las soluciones se vierten en terrenos que resisten a la accion de las corrientes de agua, el radioestroncio queda retenido por las rocas. En el segundo caso, cuando los elementos radiactivos penetran directamente en las capas acuiferas, el radioestroncio es arrastrado por las corrientes subterraneas y penetra tambien en las rocas, en las que su migracion se combina con un proceso de absorcion y desorcion. (author) [Russian] Ispol'zuja process ustanovivshejsja fil'tracii, bylo provedeno issledovanie sorbcii radiojelementov v prirodnyh uslovijah. S momenta ustanovlenija fil'tracii v rastvor vvodilis' radiojelementy, i process prodolzhalsja v techenie 4h mesjacev. Zatem posredstvom burenija otbiralis' proby grunta s razlichnyh glubin i analizirovalis' na soderzhanie radiojelementov. Rasprostranenie radioizotopov nabljudalos' do glubiny ne

  17. U-Pb geochronology of Martín García, Sola, and Dos Hermanas Islands (Argentina and Uruguay): Unveiling Rhyacian, Statherian, Ectasian, and Stenian of a forgotten area of the Río de la Plata Craton

    Science.gov (United States)

    Santos, João O. S.; Chernicoff, Carlos J.; Zappettini, Eduardo O.; McNaughton, Neal J.; Greau, Y.

    2017-12-01

    The Río de la Plata Craton is one of the three major cratons of South America. The craton is largely covered by sedimentary basins where its most exposed area is Buenos Aires-Piedra Alta Province (Chernicoff et al., 2014). This province includes the Martín García Island in the confluence of Uruguay River and the Río de la Plata estuary. Despite to be a reference area for the craton the Martín García Island lacks modern geological investigation. We present U-Pb SIMS (secondary ion mass spectrometer) geochronological data on zircon and titanite, as well as Hf isotope determinations on zircon, from rocks of Martín García Island (Argentina), Sola and Dos Hermanas Islands (Uruguay) and from Paso Severino Formation (Uruguay). We investigated: 1) Rhyacian intermediate-to acidic plutonic, arc-type rocks of the Florida Belt dated between 2090 Ma and 2115 Ma, derived from juvenile Neoarchean crust (TDMHf: 2.52 Ga; average εHf: +3.62); 2) Rhyacian metadacite (San José metamorphic belt) of 2127 Ma; 3) Statherian metagabbros of 1724-1734 Ma, with Transplatense inheritance; 4) Early Ectasian metagabbro of 1392 Ma, with Rhyacian inheritance; and 5) Stenian metagabbros of 1193 Ma (TDMHf: 2.00 Ga, εHf: 0.1). Most of the dated orthogneisses show Brasilian-age (from 778 to 550 Ma) Pb loss in the zircons, interpreted to be caused by shearing or uplifting during Neoproterozoic. The results show that the area is not exclusively Rhyacian in age but encompasses Statherian, Ectasian, and Stenian gabbros. The last two are interpreted as distal intrusions associated to the Sunsás Orogen. All post-Transplatense metagabbros have geochemical signature of island arc basalt derived from primitive mantle with enrichment of LILE and depletion of HFSE. These characteristics point to the recurrence of magma chambers intermittently active during the Rhyacian, Statherian, Ectasian, and Stenian, all with a similar source. The term "Transplatense" is used to replace "Trans-Amazonian" events

  18. Imaginarios en disputa o sobre la territorialización de un conflicto urbano. El caso de “La Canchita de los Bomberos” (Mar del Plata, Argentina

    Directory of Open Access Journals (Sweden)

    María Laura Canestraro

    2015-05-01

    Full Text Available Apenas transcurridos tres meses de la creación del “Programa Crédito Argentino del Bicentenario para la Vivienda Única Familiar”, el Municipio de General Pueyrredón anuncia las tierras disponibles para comprometer en su implementación; entre ellas, el predio conocido como “Canchita de los Bomberos” de la ciudad de Mar del Plata. Frente a ello, se conforma un grupo de vecinos autoconvocados en defensa de su utilización como espacio público-verde, llevando a cabo diversas estrategias cuyo objetivo es evitar la construcción de viviendas en esa zona. Paralelamente, otras personas manifiestan su parecer en relación a la ejecución del programa y desarrollan prácticas que cuestionan la legitimidad de las demandas sostenidas por aquellos vecinos. El propósito del artículo es analizar las formas de apropiación simbólica que se refuerzan y/o modifican en función de la disputa; lo que Melé (2003 llama “el proceso de territorialización del conflicto”. Se argumenta que, aunque se produce un choque de imaginarios (Hiernaux; 2008a, emerge un imaginario dominante que logra imponerse y legitimar el uso y disfrute del espacio a su favor.

  19. Una metodología sistemática para el análisis de los espacios públicos. El caso de la ciudad de La Plata

    Directory of Open Access Journals (Sweden)

    Silvina Adriana Moro

    2011-06-01

    Full Text Available La sociedad moderna vive un intenso proceso de transformaciones sociales que, en la ciudad de La Plata, se vienen produciendo desde principios de la década de los años 90. Estas transformaciones están relacionadas con el aumento de la población y con el crecimiento urbano, resultando así necesidad de contar con espacios abiertos adecuados, que permitan el descanso, la distracción y el recreo familiar.En este sentido y desde el punto de vista del paisaje construido, la ciudad es objeto de permanentes cambios a lo largo del tiempo, que responden tanto a procesos endógenos como así también a procesos exógenos, formando parte de un proceso más amplio que se caracteriza por el acelerado crecimiento de la población urbana. Estos procesos de transformación, siempre en alguna medida afectan a la memoria de los habitantes, a las actividades del lugar y la vida colectiva de la ciudad. Son procesos complejos donde la idea es enlazar las exigencias funcionales de la ciudad de hoy con la historia de la misma ciudad. Además estos mismos procesos generalmente emplean intervenciones de carácter físico que ordenan el espacio y contribuyen con nuevas perspectivas de desarrollo.

  20. Jóvenes en partidos políticos de La Plata. Una mirada sobre los estudios de los jóvenes y la práctica política

    Directory of Open Access Journals (Sweden)

    Marcos Mutuverria

    2011-06-01

    Full Text Available Normal 0 21 false false false MicrosoftInternetExplorer4 El presente informe manifiesta los recorridos teóricos iniciales de la tesis doctoral “Jóvenes en partidos políticos tradicionales en la región La Plata”, que se propone indagar cuál es la construcción de subjetividad, prácticas y trayectorias de los y las jóvenes pertenecientes a partidos políticos tradicionales argentinos en la ciudad de La Plata. En este sentido, el artículo refleja un mapeo en el campo de los estudios que relacionan a los jóvenes con la política (y el rol de los jóvenes en partidos políticos con las primeras consideraciones del tesista para avanzar con el análisis en sus lógicas de acción partidarias, como parte de grupalidades con disputas de poder, y en clave reflexiva sobre condiciones de género y clase en vínculo con lo etáreo al interior de los propios partidos políticos.

  1. Estudio comparativo de efectividad de un apósito de plata nanocristalina frente a sulfadiazina argéntica en el tratamiento de pacientes quemados Comparative study on the effectiveness of a dressing of nanocrystalline silver opposite to the use of silver sulfadiazine in burned patients treatment

    Directory of Open Access Journals (Sweden)

    J.F. Salvador Sanz

    2011-09-01

    Full Text Available La plata es un producto utilizado como agente antimicrobiano desde la antigüedad y ya a finales del siglo XIX se empezaron a utilizar compuestos de plata con finalidades médicas. La utilización tópica de la crema de sulfadiazina argéntica al 1 % se considera mayoritariamente como tratamiento de elección para las quemaduras a fin de tratar o prevenir la infección local. El objetivo de este artículo es comparar el tratamiento con Acticoat® (plata nanocristalina 15 nanómetros frente al tratamiento con sulfadiazina argéntica, ambos regímenes en igualdad de condiciones y un mismo centro de quemados. También se realiza una revisión de la literatura reciente sobre los factores de riesgo para la infección en quemaduras, las medidas que se utilizan para prevenirla y su importancia en la disminución de la morbi-mortalidad.Silver is a product that has been used as antimicrobial agent from ancient times; at the end of the XIXth century silver compounds were used with medical purposes. The use of silver sulfadiazine to 1 % cream is considered as gold standard for local treatment of burns in order to prevent or to treat local infection We compare treatment with Acticoat® (nanocrystalline silver 15 nanometers and silver sulfadiazine, both sistems on equal terms and in the same medical burned center. We review recent literature of risk factors for burn infection, methods to prevent it and to dininish morbimortality in burned patients.

  2. Análisis comparativo de diferentes métodos de picado automático de fases en terremotos registrados en la Estación Sismológica de La Plata (LPA

    Directory of Open Access Journals (Sweden)

    Juan I Sabbione

    2011-12-01

    Full Text Available Analizamos ocho métodos de detección y picado automático de fases internas de terremotos. Entre ellos, tres son métodos convencionales, dos son métodos nuevos desarrollados a partir de mejoras a los métodos convencionales, y los otros tres son adaptaciones a métodos originalmente concebidos para picado de primeros arribos en datos de sísmica de exploración. Para analizar los métodos, seleccionamos once registros de una hora de duración obtenidos en la Estación Sismológica de la Plata (LPA correspondientes a terremotos regionales y telesísmicos con magnitudes mayores a 6 (Mw y diversas distancias epicentrales y profundidades de foco. Los registros elegidos fueron previamente picados manualmente por un analista. Se buscó picar de manera automática un total de 30 fases, de las cuales 25 habían sido originalmente observadas por el analista. Las otras 5 fases, fueron detectadas a partir de la aplicación de los métodos automáticos, y luego corroboradas mediante el modelo IASP91. Se estudió la eficiencia de los métodos a partir del porcentaje de detecciones obtenidas y del porcentaje de picados falsos generados. Se analizaron también los errores en los picados desde un enfoque estadístico para estimar las exactitudes y precisiones de los métodos propuestos. Este análisis permitió realizar una valoración relativa de los ocho métodos de picado automático propuestos. Los resultados obtenidos revelan que algunos de los métodos exhiben ventajas significativas por sobre otros. Estos métodos que muestran mejor desempeño serían apropiados para realizar sistemáticamente el picado automático, tanto para estudios de sismología global como para estudios de sismicidad, especialmente cuando se cuenta con un gran volumen de datos.We analyzed eight methods of detection and automatic body phase picking. Three of them are conventional methods, two are new methods developed from improvements to conventional methods, and the other

  3. Selección de sonidos para in curso de inmersión de español como lengua segunda y extranjera (ELSE para angloparlantes: caso de aplicación en el programa de español para extranjeros de la Universidad Nacional de Mar del Plata, Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Sofía Romanelli

    2013-03-01

    Full Text Available Aquest article té tres objectius: proposar una metodologia per a la selecció dels sons de l’espanyol com a llengua segona i estrangera (ELSE per a ensenyar en un curs d’immersió, presentar una anàlisi contrastiva dels sons vocàlics i consonàntics de l’espanyol del Riu de la Plata (ERP i de l’anglès americà general (AAG, i elaborar un inventari dels sons de l’ERP que haurien de ser tractats en una classe d’ELSE.

  4. Implementación del Examen Clínico Objetivo Estructurado para la evaluación de competencias clínicas en el curso de Semiología de la carrera de Medicina Veterinaria de la Universidad Nacional de La Plata

    OpenAIRE

    Cánepa, Paula Analía

    2013-01-01

    El proyecto de intervención académica que aquí se desarrolla, consiste en implementar el examen clínico objetivo estructurado para la evaluación de habilidades y competencias clínicas (en adelante OSCE), en el curso de Semiología de la carrera de Ciencias Veterinarias de la Universidad Nacional de la Plata. Entendiendo por competencia, a la capacidad de poner en práctica destrezas, aptitudes y conocimientos necesarios para la construcción de la mirada clínica del futuro profesional. Dichas co...

  5. Determinación del potencial genotóxico de las nanopartículas de plata mediante el análisis del ciclo celular, la apoptosis y el ensayo del cometa en la línea celular beas-2b

    OpenAIRE

    Vela Romero, Lourdes Amparo

    2012-01-01

    El uso de nanomateriales en productos de consumo diario está incrementándose rápidamente. Por lo tanto, dadas las propiedades de las nanopartículas, su exposición puede representar un riesgo para la salud de los trabajadores de la industria y de la población en general. Entre los nanomateriales, debido a su capacidad antimicrobiana, las nanopartículas de plata muestran un gran potencial en las aplicaciones médicas y así su uso cada vez más extendido. Dada la escasa información existente...

  6. Cinema Queer Latinoamericano: diálogos e entrelaçamentos em gênero e (homosexualidades por meio dos filmes “Plata Quemada” e “Morango e Chocolate”

    Directory of Open Access Journals (Sweden)

    Sulivan Charles Barros

    2015-12-01

    Full Text Available As narrativas cinematográficas exercem grande poder sobre o público. Elas veiculam e constroem relações de gênero e sexualidades o que torna de extrema relevância a investigação dos discursos/práticas/efeitos do cinema na constituição de valores e representações sociais e também contribuem para delimitar os papéis dicotômicos entre homem/mulher, masculino/feminino, hetero/homo, bem como investigar abordagens que problematizem as sexualidades de forma interseccional. O cinema foi priorizado aqui como um lócus de criação marcado pela experiência das identidades de gênero e pela possibilidade de ser o cinema um recurso que possibilita a construção do conhecimento histórico, pois o cinema possui mensagens fílmicas individuais e múltiplas, mensagens que trazem valores culturais, sociais e ideológicos de uma sociedade. Neste sentido, foi analisado os filmes Plata Quemada de Marcelo Piñero e Morango e Chocolate de Tomás Gutiérrez Alea. Estes filmes, no meu entendimento, estão centrados em subjetividades queer que podem contribuir para a crítica cultural às sociedades patriarcais, machistas e sexistas, propiciando outros sentidos para o imaginário social. Buscou-se conferir também nesta pesquisa às práticas discursivas queer esboçadas em parte no cinema, embora tenha claro que elas não são lineares, nem uniformes. Palavras-Chave: Cinema; América Latina; Gênero; Sexualidades. *** Abstract: Cinematographic narratives have great power over the public. They convey and to build gender relations and sexuality which makes it extremely important to investigate the discourse / practices / film effects in the formation of values and social representations and also contribute to delimit the dichotomous roles between male / female, male / female, hetero / homo and investigate approaches that problematize the sexualities of intersectional way. The film was prioritized here as a locus of creation marked by the experience of

  7. Neutron activation analysis of ancient silver coins; Analyse d'anciennes pieces d'argent par activation neutronique; Nejtronozyj aktivatsionnyj analiz starinnykh serebryanykh monet; Analisis de antiguas monedas de plata por activacion neutronica

    Energy Technology Data Exchange (ETDEWEB)

    Aitken, Martin J; Emeleus, Vera M; Hall, Edward T [Research Laboratory for Archaeology and the History of Art, University of Oxford (United Kingdom); Kraay, Colin M [Heberden Coin Room, Ashmolean Museum, University of Oxford (United Kingdom)

    1962-01-15

    0,884 MeV emis par l'argent-110m (253 jours). Des mesures de la desintegration ont permis un controle d'identite. La methode qui utilise en elles-memes les courbes de desintegration de l'activite gamma totale n'est pas suffisamment precise. On souligne l'importance d'etalons a peu pres identiques aux pieces etudiees pour obtenir des resultats de haute precision. (author) [Spanish] Los autores han determinado cuantitativamente el oro y el cobre presentes como impurezas en 500 monedas de plata griegas del siglo U antes de Cristo. Despues de activar los componentes por irradiacion neutronica, los determinaron con ayuda de un espectrometro gamma. Estudiaron monedas procedentes de ocho ciudades y reinos distintos. Encontraron que el contenido de oro para diferentes grupos de monedas oscila entre 0,02 y 0,3 por ciento, en tanto que el de cobre varia entre 0,1 y 10 por ciento. Los autores han podido demostrar la existencia de relaciones comerciales entre las distintas ciudades y han encontrado pruebas de que ciertas monedas habian sido falsificadas deliberadamente rebajando su contenido de plata. Han descubierto asimismo que algunas de las monedas estaban enchapadas, dato que se ignoraba. Determinaron el contenido de oro midiendo la intensidad de los rayos gamma de 0,411 MeV emitidos por el {sup 198}Au (2,69 dias); para el cobre emplearon la radiacion de 0,511 MeV que el {sup 64}Cu (12,8) emite por aniquilacion de positrones y para la plata, la radiacion gamma de 0,884 MeV de la {sup 110m}Ag (253 dias). Como comprobacion de identidad, los autores efectuaron mediciones de la desintegracion. La tecnica que emplea las curvas mismas de desintegracion total por actividad gamma no posee una sensibilidad suficiente. Los autores recalcan la conveniencia de utilizar facsimiles patron aproximados para alcanzar resultados de cierta precision. (author) [Russian] Kolichestvo zolota i medi, soderzhashchikhsya v kachestve primesi v 500 grecheskikh serebryanykh monetakh V veka do nashej

  8. Characterization of the interaction layer in diffusion couples U-Mo-Zr/Al and U-Mo-Zr/Al-A356 at 550 C degrees; Caracterizacion de la zona de interaccion en pares de difusion a 550 grados C U-Mo-Zr/Al y U-Mo-Zr/Al-A356

    Energy Technology Data Exchange (ETDEWEB)

    Komar Varela, Carolina; Arico, Sergio; Mirandou, Marcela; Balart, Silvia; Gribaudo, Luis [Comision Nacional de Energia Atomica, General San Martin (Argentina). Dept. de Materiales; com, carolinakomar@gmail

    2007-07-01

    Out-of-pile diffusion experiments were performed between U-7 wt.% Mo-1 wt.% Zr and Al or Al A356 (7,1 wt.% Si) at 550 C degrees. In this work morphological characterization and phase identification on both interaction layers are presented. They were carried out by the use of different techniques: optical and scanning electron microscopy, X-ray diffraction and WDS microanalysis. In the interaction layer U-7 wt.% Mo-1 wt.% Zr/Al, the phases UAl{sub 3}, UAl{sub 4}, Al{sub 20}Mo{sub 2}U and Al{sub 43}Mo{sub 4}U{sub 6} were identified. Similar results in the interaction layer of the U-7 % Mo/Al at 580 C degrees were previously obtained. In the interaction layer U-7 wt.% Mo-1 wt.% Zr/Al A356, the phases U(Al,Si){sub 3} with 25 at.% Si and Si{sub 5}U{sub 3} were identified. This last phase, with a higher Si concentration, was identified with X-ray diffraction synchrotron radiation performed at the National Synchrotron Light Laboratory, Campinas, Brazil. (author) [Spanish] Se realizaron experiencias fuera de reactor en pares de difusion quimica U-7 % Mo-1 % Zr/Al y U-7 % Mo-1 % Zr/Al A356. En este trabajo se presentan los resultados de la caracterizacion morfologica e identificacion de fases presentes en la zona de interaccion que se forma al ser sometidos a un tratamiento isotermico de 1,5 h a 550 grados C. Las tecnicas utilizadas fueron: microscopia optica y electronica de barrido, difraccion de rayos X y microanalisis cuantitativo por sonda electronica. En la zona de interaccion correspondiente al par U-7 % Mo-1 % Zr/Al se identificaron las fases UAl{sub 3}, UAl{sub 4}, Al{sub 20}Mo{sub 2}U y Al{sub 43}Mo{sub 4}U{sub 6}. Estas cuatro fases fueron identificadas en pares U-7 % Mo/Al a 580 grados C en trabajos anteriores. En la zona de interaccion correspondiente al par U-7 % Mo-1 % Zr/Al A356 se identificaron las fases U(Al,Si){sub 3} (con una concentracion de 25 %at.Si) y Si{sub 5}U{sub 3}. Este compuesto rico en Si solo pudo ser identificado mediante la utilizacion de

  9. Characterization of the voltage control systems and speed of a synchronous machine of high power for short circuit testing; Caracterizacion de los sistemas de control de voltaje y velocidad de una maquina sincrona de alta potencia para pruebas de corto circuito

    Energy Technology Data Exchange (ETDEWEB)

    Segura Ozuna, Victor Octavio; Hernandez Rodriguez, Isaura Victoria; Alcaide Godinez, Indira Xochiquetzal; Garduno Ramirez, Raul; Montero Cervantes, Julio Cesar [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Ruiz Rodriguez, Genaro; Martinez Torres; Ricardo [CFE-LAPEM, Irapuato, Guanajuato (Mexico)

    2012-07-01

    This paper introduces a characterization of the behavior of the speed and voltage control systems of a special purpose synchronous machine (GCC) based on measuring and monitoring physical signals, and recording of the sampled waveforms. Basically, the GCC supplies the energy to perform high-power short-circuits tests to certify electrical equipment and components, as required by the Comision Federal de Electricidad (CFE) in Mexico. The GCC operates alternately as motor and generator. With the GCC operating as motor, speed control during startup, acceleration, re-acceleration and braking is carried out by a static frequency converter (SFC). Complementary, the voltage controller manipulates excitation power to control terminal voltage when the GCC operates as generator and regulates excitation current when the GCC operates as motor. Compared to conventional voltage regulation systems, which must go off in case of short-circuit, the GCC voltage regulator must keep controlling field excitation to maintain the required line current and terminal voltage during short-circuit tests. Monitoring of physical signals was carried out with a portable data acquisition system based on SCXI and PXI digital platforms. A total of 78 signals were monitored with a 6 kHz sampling rate that was enough to obtain detailed signal waveforms. Data captured was processed and plotted for analysis. The signal graphs show the current real behavior of both, the voltage control system and the speed control system, and constitute a precise characterization of their behavior. [Spanish] Este documento presenta una caracterizacion del comportamiento de los sistemas de control de velocidad y voltaje de una maquina sincrona de proposito especial (GCC) basada en la medicion y monitoreo de senales fisicas, asi como en el registro de las formas de onda muestreadas. Basicamente, la GCC suministra la energia para efectuar pruebas de corto circuito de alta potencia para certificar equipo y componentes

  10. Impacto de la envolvente en la demanda de energía en calefacción residencial de la región metropolitana de La Plata, tomando como caso testigo el reciclado energético de una vivienda

    Directory of Open Access Journals (Sweden)

    María de la Paz Diulio

    Full Text Available Resumen El área metropolitana de La Plata representa el 1,6% de las viviendas de la Argentina. A partir del análisis del reciclado de una vivienda se construyen indicadores básicos con el fin de proponer una metodología que facilite la extrapolación, a nivel regional, del impacto que causaría un programa de eficiencia energética en viviendas. Se exponen desde el nivel micro a macro los resultados obtenidos en un contexto de carestía energética y recurrentes crisis en la oferta de combustibles y electricidad en la Argentina. La mejora en la resistencia térmica de muros y techos en todo el parque residencial de La Plata conllevaría a una reducción del 12% de la energía consumida en calefacción, y un ahorro de 30.000 TEP/año. Se concluye que la incidencia que implica la colocación de aislación adicional respecto del costo de la construcción justifica su uso, resolviendo parcialmente la falta de combustibles en el país, reduciendo gastos fijos en la vivienda, otorgando confort térmico a los usuarios y generando reactivación del sector de la construcción.

  11. Determinación de las constantes ópticas de películas delgadas de óxido de estaño y de plata para su utilización en recubrimientos multicapa de baja emisividad

    Directory of Open Access Journals (Sweden)

    Martín Palma, R. J.

    2000-08-01

    Full Text Available The determination of the values of the optical constants (n, refractive index and k, extinction coefficient in the visible range of both silver (Ag and tin oxide (SnO2 films is a necessary condition to predict the behaviour of a SnO2/Ag/SnO2 multilayer for low emissivity coatings, improving the visual comfort. For this purpose, thin films of Ag and SnO2 with a thickness similar to that of multilayer coatings (90 Å and 380 Å respectively were used in order to avoid the thickness dependence of the optical constants. A simulation computational program based on the matrix method was employed to estimate the values of the optical constants of these films in the visible range. It has been also determined the dependence on the wavelength of the absorption coefficient (α, as well as the value of the energy gap, and the nature of the optical transitions.

    La determinación de los valores de las constantes ópticas (n, índice de refracción y k, coeficiente de extinción en el espectro visible de películas tanto de plata (Ag como de óxido de estaño (SnO2, es una condición necesaria para predecir el comportamiento de un recubrimiento multicapa de baja emisividad con la estructura SnO2/Ag/SnO2 en relación al confort visual. Para este propósito, se han caracterizado láminas delgadas de Ag y de SnO2 con un espesor similar al que tienen en los recubrimientos multicapa (90 Å y 380 Å respectivamente, evitando así la dependencia con el espesor de las constantes ópticas. Se ha utilizado un programa informático de simulación basado en el método matricial para determinar los valores de las constantes ópticas de dichas películas en el espectro visible. Ha sido determinada asimismo la dependencia del coeficiente de absorción (α con la longitud de onda, así como el valor del ancho de banda prohibida del óxido de estaño, y la naturaleza de la transición óptica.

  12. Short-term toxicity of hexavalent-chromium to epipsammic diatoms of a microtidal estuary (Río de la Plata): Responses from the individual cell to the community structure

    International Nuclear Information System (INIS)

    Licursi, M.; Gómez, N.

    2013-01-01

    Highlights: •Diatom's nuclear abnormalities were significantly higher as consequence of chromium exposure. •Diatoms and chlorophytes increased in treatment microcosms. •Nitzschia palea proportion increased significantly in the treatment microcosms. -- Abstract: Diatoms are an integral and often dominant component of the benthic microalgal assemblage in estuarine and shallow coastal environments. Different toxic substances discharged into these ecosystems persist in the water, sediments, and biota for long periods. Among these pernicious agents, the toxicity in diatoms by metal is linked to different steps in the transmembrane and internal movements of the toxicant, causing perturbations in the normal structural and functional cellular components. These changes constitute an early, nontaxonomic warning signal that could potentially serve as an indicator of this type of pollution. The aim of this work was to study the environment-reflecting short-term responses at different levels of organization of epipsammic diatoms from the Río de la Plata estuary, Argentina that had been exposed to hexavalent chromium within experimental microcosms. To this end we monitored: (i) changes in the proportion of the diatoms in relation to other algal groups at the biofilm community level; (ii) shifts in species composition at the diatom-assemblage level; (iii) projected changes in the densities of the most representative species at the population level through comparison of relative growth rates and generation times; and (iv) the cytological changes at the cellular and subcellular levels as indicated by the appearance of teratological effects on individuals and nuclear alterations. The epipsammic biofilms were exposed for 96 h to chromium at a concentration similar to that measured in highly impacted sites along the coast (80 μg L −1 ). Chromium pollution, at this concentration and short exposure time did not affect the algal biomass and density of these mature biofilms. The

  13. Short-term toxicity of hexavalent-chromium to epipsammic diatoms of a microtidal estuary (Río de la Plata): Responses from the individual cell to the community structure

    Energy Technology Data Exchange (ETDEWEB)

    Licursi, M., E-mail: malena@ilpla.edu.ar; Gómez, N.

    2013-06-15

    Highlights: •Diatom's nuclear abnormalities were significantly higher as consequence of chromium exposure. •Diatoms and chlorophytes increased in treatment microcosms. •Nitzschia palea proportion increased significantly in the treatment microcosms. -- Abstract: Diatoms are an integral and often dominant component of the benthic microalgal assemblage in estuarine and shallow coastal environments. Different toxic substances discharged into these ecosystems persist in the water, sediments, and biota for long periods. Among these pernicious agents, the toxicity in diatoms by metal is linked to different steps in the transmembrane and internal movements of the toxicant, causing perturbations in the normal structural and functional cellular components. These changes constitute an early, nontaxonomic warning signal that could potentially serve as an indicator of this type of pollution. The aim of this work was to study the environment-reflecting short-term responses at different levels of organization of epipsammic diatoms from the Río de la Plata estuary, Argentina that had been exposed to hexavalent chromium within experimental microcosms. To this end we monitored: (i) changes in the proportion of the diatoms in relation to other algal groups at the biofilm community level; (ii) shifts in species composition at the diatom-assemblage level; (iii) projected changes in the densities of the most representative species at the population level through comparison of relative growth rates and generation times; and (iv) the cytological changes at the cellular and subcellular levels as indicated by the appearance of teratological effects on individuals and nuclear alterations. The epipsammic biofilms were exposed for 96 h to chromium at a concentration similar to that measured in highly impacted sites along the coast (80 μg L{sup −1}). Chromium pollution, at this concentration and short exposure time did not affect the algal biomass and density of these mature

  14. Trans-Amazonian U-Th-Pb monazite ages and P-T-d exhumation paths of garnet-bearing leucogranite and migmatitic country rock of the southeastern Tandilia belt, Rio de la Plata craton in Argentina

    Science.gov (United States)

    Martínez, Juan Cruz; Massonne, Hans-Joachim; Frisicale, María Cristina; Dristas, Jorge A.

    2017-03-01

    A garnet-bearing leucogranite and two country rocks from the Transamazonian Tandilia belt of the Rio de la Plata craton were studied in detail. The leucogranite contains garnet with homogeneous composition of pyr6(gros + andr)2spes5alm87. In a garnet-biotite migmatite, the core and rim compositions of garnet are pyr1.7(gros + andr)5spes5.6alm87.7 and pyr1.2(gros + andr)5.5spes6.7alm86.6, respectively. These compositions in a sillimanite-garnet-muscovite migmatite are pyr4(gros + andr)2.7spes2.7alm90.6 and pyr2.7(gros + andr)4spes3.2alm90.1, respectively. We used this information to decipher the P-T evolution of the rocks applying P-T and T-H2O pseudosections with the PERPLE_X computer software package taking into consideration deformational microstructures. The leucogranite records an isothermal decompression from 5.3 to 3.8 kbar at 665 °C. The garnet-biotite migmatite was exhumed from 5.5 kbar at 630 °C to 4.3 kbar at 615 °C and the sillimanite-garnet-muscovite migmatite from supersolidus conditions of 670 °C and 3.6 kbar to 625 °C at 2.4 kbar. Late andalusite formed in this rock. Seventy four analyses of 28 monazite grains of the country rocks yielded three groups of U-Th-Pb ages which were related to a collisional event (I: ca. 2.13-2.14 Ga.), a postcollisional thermal overprint (II: ca. 2.01 Ga) and slow cooling of the orogen (III: 1.80-1.90 Ga). Inherited ages of 2.28 and 2.25 Ga could refer to an early accretionary stage of the orogen. An age of 2.41 Ga indicates the presence of recycled Siderian continental crust. Synkinematic crystallization of melts and the subsolidus development of an S2-foliation, demonstrated by deformational microstructures, occurred during the exhumation of the studied area from depths of 18 km to 8 km in the time interval 2.01-1.90 Ga.

  15. Resurrección y recreación de Dafnis y Cloe en la Edad de Plata (1868-1936: moral, filología y espacio literario

    Directory of Open Access Journals (Sweden)

    Hualde Pascual, Pilar

    2011-12-01

    Full Text Available The aim of this paper is to search for the impact that the Greek novel Daphnis and Chloe had in several authors of the Silver Age of the Spanish culture, on the basis of a chronological compilation and critical interpretation of the data. In this way, this paper will try to demonstrate that, from the time of Juan Valera’s translation onwards, some writers of the late 19th century resort to mentioning the characters of Longus’ novel as a mere aesthetic resource imposed by fashion, while others look at its plot to find the inventio of the subject of their novels. Also, this paper will try to demostrate that certain authors, belonging already to the Generations of ’98 and ’27 and with more or less knowledge of Greek, rediscover Las Pastorales and use them to polarize their opinions about sexuality, in the framework of the so-called lyric novel. Finally, the paper will highlight the resort to Daphnis and Chloe made by certain writers of the Generation of ’27, either with a symbolic function, either to deconstruct a classic by introducing it into the aesthetics of modernity.El trabajo pretende rastrear los ecos que la novela griega Dafnis y Cloe ha dejado en diversos autores de la Edad de Plata de la cultura española, partiendo de una recopilación cronológica y de una interpretación crítica de los datos. De esta manera se intentará demostrar que, a partir de la traducción de Juan Valera, algunos escritores de finales del XIX recurren a la mención de los personajes de la novela de Longo como mero recurso estético impuesto por la moda, mientras que otros buscan en su trama la inventio del asunto de sus novelas. Intentaremos demostrar, asimismo, que ciertos autores, pertenecientes ya a las generaciones del 98 y del 14, con una formación mayor o menor en la lengua griega, redescubren Las Pastorales y las utilizan para polarizar en torno a ellas sus ideas respecto a la sexualidad, en el marco de la llamada novela lírica. Finalmente se

  16. Depreciación de la plata, políticas públicas y desarrollo empresarial. Las pequeñas y medianas empresas mineras mexicanas de Pachuca y Real del Monte

    Directory of Open Access Journals (Sweden)

    Uribe Salas, José Alfredo

    2011-08-01

    Full Text Available This article studies the business strategies and capacity of small and medium-sized mining enterprises that operated in the Pachuca-Real del Monte mining district in Mexico in the late 19th century. In a regional economic context dominated by the monopoly of the Compañía de Minas Real del Monte y Pachuca, small and medium-sized enterprises managed to obtain advantages from both the silver depreciation in the international currency markets and the Mexican public policies focused precisely on mitigating the fall in the price of silver after 1873. The way that some minor and medium-sized local entrepreneurs injected new life into mining activities in the region, thereby actually benefiting from the international circumstances, is analysed. In sum, it was the small and medium-sized mining companies that supported the productive and business development that characterized the period of mining growth in the district during the dictatorship of President Porfirio Díaz.

    Se estudian las estrategias empresariales y la capacidad de las pequeñas y medianas empresas mineras que operaron en el Distrito de Real del Monte y Pachuca para obtener ventajas relativas tanto de la depreciación de la plata en los mercados internacionales como de las políticas públicas establecidas por los gobiernos mexicanos después de 1873 para paliar la caída del valor argentífero, en un contexto de monopolio minero-metalúrgico promovido por la Compañía de Minas Pachuca y Real del Monte. Se analiza cómo algunos pequeños y medianos empresarios locales dieron nuevos bríos a la actividad minera y cómo se vieron beneficiados con la situación internacional. Se concluye que fueron las pequeñas y medianas empresas las que sustentaron el desarrollo productivo y empresarial que caracterizó el auge minero en la región de estudio durante periodo porfirista en México.

  17. Mitigación del riesgo de inundación a partir de la planificación del paisaje. Caso: Arroyo del Gato. Gran la Plata (Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Daniela Vanesa Rotger

    2018-05-01

    Full Text Available El siguiente trabajo pone en discusión el papel que desempeña la planificación del paisaje fluvial en la mitigación del riesgo hídrico, a través del análisis de un proyecto desarrollado para la Cuenca del Arroyo del Gato, en el marco del conglomerado urbano denominado como Gran La Plata. A nivel mundial las estrategias de mitigación del riesgo de inundaciones han incorporado la mirada paisajística, dejando de lado progresivamente el enfoque basado únicamente en obras defensivas y dando lugar a acciones preventivas que se basan en la consideración de las dinámicas del medio natural y fomentan la sensibilidad hacia los sistemas hídricos. En el caso que se analiza prima aún el enfoque basado en las obras de ingeniería hidráulica, así como un escaso reconocimiento del valor ecológico y paisajístico asociado al curso de agua. Siendo la Cuenca del Arroyo del Gato la más densificada de la región, como también una de las más afectadas por elevados niveles de riesgo hídrico, la planificación del paisaje puede contribuir a las estrategias de mitigación de dicho riesgo. En concreto, se realiza aquí un trabajo de carácter cualitativo, basado en el relevamiento y sistematización de estrategias de mitigación del riesgo asociadas al paisaje, exponiendo su aplicación en un proyecto desarrollado para la Cuenca del Arroyo del Gato y considerando su aplicación a nivel metropolitano. El desarrollo de una estrategia de espacios públicos con diferentes funciones según los distintos sectores de la cuenca, demuestra que es posible asociar planificación del paisaje y mitigación del riesgo, lo que representa un abordaje innovador en una región en la que no existe apreciación del paisaje fluvial, ni integralidad en la gestión del riesgo.

  18. Overcoming dualisms: socio-productive trayectories in the analysis of horticultural social structure's transformations in La Plata Superando dualismos: trayectorias socio-productivas en el abordaje de las transformaciones en la estructura social hortícola platense

    Directory of Open Access Journals (Sweden)

    María Alejandra Waisman

    2011-01-01

    Full Text Available The present article presents the main guidelines of the theorical and methodological strategy used in the underway investigation about horticultural social structure's transformations in La Plata's city in the last 20 years. This approach tries to overcome the dualism action-structure and individual-society, thinking them as being complementary aspects in the analysis of social reality. The contributions and limitations of two paradigms which are pronounced as antagonistic in explaining social behavior and the theories seeking to reconcile both approachs are analized. The trajectory concept is proposed as mediating concept used to bring together the historical process, the structural constrictions and the human agency. Linked to the teorical approach a qualitative metodological strategy was implemented based on semi-structured interviews and participant observation. Finally, this article argues that the major transformations that took place during the '90s in the social space investigated , affected the social status of horticultural producer.En el presente artículo se presentan los principales lineamientos de la estrategia teórico-metodológica que se está implementando en la investigación en curso, en la que se busca dar cuenta de las transformaciones en la estructura social hortícola platense, acaecida en los últimos 20 años. Este enfoque busca superar los dualismos acción y estructura e individuo y sociedad, pensándolos como aspectos complementarios en el abordaje de la realidad social. En este sentido, se revisan los aportes y limitaciones de dos paradigmas que se pronuncian como antagónicos en la explicación de la conducta social, como así también los aportes teóricos que buscan reconciliar ambas posturas. Se propone el concepto de trayectorias como concepto mediador, que permite reunir en el análisis tanto la historicidad de los procesos sociales, las constricciones estructurales y la agencia de las sujetos. A su vez

  19. Sedimentary petrology of oil well rock cores; Petrologia sedimentaria de nucleos de rocas de pozos petroleros

    Energy Technology Data Exchange (ETDEWEB)

    Izquierdo M, Georgina; Paredes S, Adriana [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2001-07-01

    At the request of PEMEX Exploration and Production (PEP), in the area of Geology of the Gerencia de Geotermia, the necessary methodology has been integrated to carry out the geologic characterization of cores obtained during the oil well drilling. The integrated studies have been of utility for PEMEX, because they provide detailed information on the processes, conditions of deposition and diagenesis that occur in sedimentary rocks. On the other hand, this geologic information contributes to the update of the geologic model of the field in study. [Spanish] A solicitud de PEMEX Exploracion y Produccion (PEP), en el area de Geologia de la Gerencia de Geotermia, se ha integrado la metodologia necesaria para llevar a cabo la caracterizacion geologica de nucleos obtenidos durante la perforacion de pozos petroleros. Los estudios integrados han sido de utilidad para PEMEX, pues proporcionan informacion detallada sobre los procesos, condiciones de depositacion y diagenesis que ocurren en rocas sedimentarias. Por otro lado, esta informacion geologica contribuye a la actualizacion del modelo geologico del campo en estudio.

  20. Social classes in La Plataïs horticulture: Exercise of theorizing, historicizing and empirical analysis Las clases sociales en la horticultura platense: Ejercicio de teorización, historización y análisis empírico

    Directory of Open Access Journals (Sweden)

    Soledad Lemmi

    2011-01-01

    Full Text Available This article provides a characterization of the social relations that prevail in vegetable production in La Plata. The work is based on the tenets of Marxism, which are used for understanding and description of the society. In the first section, a brief theoretical description of the capitalist logic of production is made following the historical materialism methodology, and proposed a designation of the subject of horticulture in the classic formulation of Marxism to capitalist social relations: landowners, bourgeois and salaried. Then empirical data is displayed on the sector that accounts of the historical formation of social classes in it. This information emerges from the analysis and study of the historical shape of La Plata horticultural land, the 1998 and 2005 horticultural census results, the confrontation and conflict register brought on by the different subjects of production over the last 50 years and ends with several contributions arising from oral histories taken from interviews. Finally, some conclusions are systematized.En este artículo se realiza una caracterización de las relaciones sociales que priman en la producción de hortalizas en La Plata. El trabajo parte de los postulados del marxismo para el entendimiento y descripción de la sociedad. En el primer apartado se realiza una breve descripción teórica de la lógica capitalista de producción siguiendo la metodología del materialismo histórico y se propone una denominación de los sujetos de la horticultura bajo la formulación clásica del marxismo para las relaciones sociales capitalistas: terratenientes, burguesía y asalariados. Luego se despliega información empírica sobre el sector que da cuenta de la conformación histórica de las clases sociales en el mismo. Esta información surge del análisis y estudio de la conformación histórica del territorio hortícola platense, los resultados de los censos hortícolas de 1998 y 2005, del registro de los

  1. Summary of Current Geological Research in the United States of America Pertinent to Radioactive Waste Disposal on Land; Bilan des Recherches Geologiques Actuelles aux Etats-Unis, du Point de Vue de l'Elimination des Dechets Radioactifs dans le Sol; 041a 0420 0414 ; Resena de las Investigaciones Geologicas que Actualmente se Efectuan en los Estados Unidos Sobre la Evacuacion de Desechos Radiactivos en el Subsuelo

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, E. S. [Geologist, US Geological Survey, Washington, DC (United States)

    1960-07-01

    radioactivite des solides organiques et inorganiques se trouvant dans les courants ; d) Action, sur le transport des radionuclides, des sediments en suspension et des matieres constituant le lit des rivieres. (author) [Spanish] Atendiendo al grado de confinamiento que los desechos radiactivos exigen para que su evacuacion se ajuste a las normas generalmente aceptadas en materia de seguridad y de proteccion de la salud, las investigaciones geologicas efectuadas con relacion a esa evacuacion pueden dividirse en tres categorias. I. Los medios que ofrecen un confinamiento maximo podran utilizarse pata retener por espacio de siglos o de milenios practicamente la totalidad de los materiales de desecho en ellos acumulados. Se estan estudiando medios de dos tipos generales: los yacimientos de sal y las formaciones permeables profundas. Sobre unos y otros se estan llevando a cabo diversos experimentos de laboratorio para estudiar la accion reciproca entre las soluciones de desechos y los materiales adecuados del subsuelo y, en el caso de los yacimientos de sal, se procede actualmente a un experimento sobre el terreno utilizando soluciones simuladas de desechos de elevada intensidad (no radiactivos). II. Los medios que ofrecen un confinamiento medio podran utilizarse para reducir considerablemente la movilidad de los desechos radiactivos a fin de que transcurra tiempo suficiente para que se produzca su desintegracion radiactiva antes de que entren en contacto con el hombre o con su cadena alimentaria. Entre los ejemplos de confinamiento medio cabe mencionar la evacuacion a poca profundidad de desechos envasados y la descarga de desechos liquidos no envasados en fosos de infiltracion. Se estan realizando investigaciones para estudiar el efecto combinado del transporte de los radionuclidos por las aguas subterraneas y de la retencion de los radionuclidos, por sorcion, en los materiales del subsuelo. III. Los medios que ofrecen un confinamiento nulo son aquellos en que los radionuclidos

  2. Académico Alberto Albornoz Plata

    Directory of Open Access Journals (Sweden)

    Alberto Albornoz Plata

    1990-04-01

    Full Text Available

    La aparición del No. 21 de la Revista “MEDICINA”, órgano de la Academia Nacional de Medicina de Colombia, marca una fecha memorable para nuestra Institución, ya que un buen amigo, buen colombiano, admirador de la obra desarrollada por la Academia, en forma gentil y generosa, se ha encargado de la financiación total de nuestra publicación, en forma trimestral y en la que se editarán 7000 ejemplares para cada número los cuales se distribuirán también por cuenta de ITALMEX a los médicos colombianos. De esta forma, es un aporte indirecto a la medicina de Colombia, pues tendremos un buen número de lectores los cuales por sus comentarios a “MEDICINA”, nos suministrarán muchas ideas útiles. También este No. 21 tendrá un aspecto distinto en la carátula: su color pasará del negro, posiblemente algo triste, a recordar los colores del escudo de la Academia, dorado y verde, que han sido los tradicionales.

    Se trata del Dr. Joaquín Ordoñez S., ampliamente conocido no sólo en el cuerpo médico, sino también en el mundo de las finanzas. Director General de un importante laboratorio farmacéutico, de mucha antiguedad, gran prestigio y que goza de la confianza de todos los médicos: ITALMEX.

    Debo recordar que hace varios años, también el Dr. Ordóñez financió en su totalidad la publicación del libro “TEMAS MEDICaS”, órgano oficial de la Academia, de los tomos VII al XI, libro que ha obtenido mucha acogida científica, y hace parte de las bibliotecas de muchos colegas. Nuevamente hoy se vincula a la Academia con nuestra Revista, el Dr. Ordóñez sea bienvenido!

    Es importante conocer algunos datos sobre la vida y actividad de nuestro patrocinador: su gran personalidad es su tarjeta de presentación. Una marcada disciplina que en todas sus labores transmite a su grupo de trabajo; todo debe ser perfecto y en las fechas acordadas; muy buen madrugador, con amabilidad, educación y dinámica permanentes, sus colabordadores encuentran siempre al jefe y al amigo. Además, las situaciones difíciles, las arregla con un particular sentido de equilibrio y sabiduría. Cualquier punto de vista de su equipo de trabajo lo oye, lo estudia y acepta si es razonable y siempre previendo el futuro. Es un verdadero guía de Alta Gerencia y así lo reconoció la UNIVERSIDAD DE NEW YORK, al otorgarle el doctorado Honoris Causa de Alta Gerencia el 31 de septiembre de 1978, en ceremonia especial; es sencillamente el reconocimiento a su actividad laboral, iniciada el 14 de agosto de 1943, en la industria farmacéutica colombiana, la cual lo llevó a la Presidencia de AFlDRO no hace muchos años, yen donde desarrolló gran labor en pro de la Farmacología y Economía, otra de las predilecciones de su estudio permanente, junto con las Ciencias de la Administración, y por eso ha podido actuar con gran éxito como consejero de muchos personajes colombianos. Además de esas cualidades, es un ferviente creyente católico, sin querer nunca imponer sus puntos de vista, pues conoce también la humildad para hacer el bien de muchos necesitados, siguiendo el ejemplo de Cristo. Por esa gran cualidad humana obtuvo del VATICANO y de manos de su Santidad Juan Pablo II, el título de Caballero Comendador de la Orden de San Gregario Magno, en Roma el 29 de mayo de 1979. Finalmente, tiene un especial don para la Publicidad que parece nació con él. Ejemplo de ésto, es la Colección de Médicos Célebres colombianos 1 Etapa, entregada el Día Panamericano del Médico, en una fiesta memorable, ofrecida al cuerpo médico el pasado 10 de diciembre de 1989, en el Salón Rojo del Hotel Tequendama.

    Sólo podemos decirle a nuestro siempre elegante y pulcro promotor de “MEDlCIN A”: j Muchas gracias!

  3. De clasistas a burócratas: el devenir de una traición. Acerca de la construcción moral del enemigo político en un sindicato de la industria del pescado (Mar del Plata - Argentina, 1997-2007

    Directory of Open Access Journals (Sweden)

    Guillermo José Colombo

    2011-01-01

    Full Text Available La noción de burocracia sindical es usualmente utilizada para describir el accionar de determinados líderes gremiales a los que se caracteriza como reformistas, poco democráticos, defensores de sus propios intereses y proclives a la integración con el Estado. La categoría ha sido generalmente usada más para condenar que para explicar. Este trabajo se basa en el análisis de las contiendas gremiales en un sindicato de la industria pesquera en Mar del Plata, Argentina. A través de trabajo de archivo y trabajo de campo, indagué el concepto de burocracia a partir del significado que ocupa en las batallas sindicales, en las que recurrentemente se construye al enemigo no solo como burócrata sino también como traidor.

  4. Apertura democrática, gobierno local y políticas urbanas. Nueva apuesta a la construcción de Mar del Plata Balnearia en la década del '80: el caso del complejo balneario La Perla

    OpenAIRE

    Cicalese, Guillermo

    2001-01-01

    La década del 80 significó para la Argentina la vuelta al sistema democrático luego de siete años de dictadura militar. Mar del Plata como el "balneario nacional" de la Argentina no escapó a los impactos sociales del modelo aperturista de la dictadura y al iniciarse la década se hacía sentir una crisis económica que sólo había sido paleada en parte por las inversiones públicas. Los cuantiosos fondos habían llegado para preparar la ciudad como sede del Mundial de Fútbol Internacional en 1978, ...

  5. La Capacitación de Recursos Humanos y los Servicios Tecnológicos como Herramienta para la Mejora Competitiva: El caso de la Región Mar del Plata, Argentina (Human resources training and technological services as tools for competitive improvement

    Directory of Open Access Journals (Sweden)

    Fernando Manuel Graña

    2012-12-01

    Full Text Available El caso presentado muestra los elementos más relevantes de la intervención de la OIT en la Región Mar del Plata. Esta tiene por objeto la generación de trabajo decente y la mejora competitiva del entramado productivo local. Los principales logros son, la constitución de 5 mesas de concertación; la definición e implementación de sus acciones estratégicas; el fortalecimiento de instituciones empresariales, sindicales, científicas, tecnológicas, de formación técnica y universitaria. La creación de 3 centros de servicios tecnológicos (naval, indumentaria, TIC y de 2 asociaciones empresarias (Indumentaria y TIC, la instalación de más de 100 máquinas industriales en escuelas técnicas, la capacitación de más de 80 formadores y más de 1800 desocupados, la recalificación de más de 100 ocupados y la formación de más de 500 técnicos, profesionales y empresarios.   ABSTRACT This case shows the most important elements in the OIT’s intervention in the Mar del Plata region. It has the goal to provide decent jobs generation and the competitive improvement of the local productive framework. Its main achievements are: the setting up of 5 discussion boards; the definition and running of strategic actions; the strengthening of entrepreneurial, labor union, scientific and technological institutions (naval, garment, TICs, and of 2 entrepreneurial associations (Garment and TICs; the installation of over a 100 industrial machines in vocational schools; the training of over 80 teachers and 1,800 jobless individuals; the requalification of more than 100 workers and training of over 500 technicians, professionals and entrepreneurs.

  6. Impacto de la aplicación de la Ley 13059 de Eficiencia Energética en relación a la nueva Ordenanza de Usos del Suelo de la ciudad de La Plata y la Norma IRAM 11900 de Etiquetado de Edificios

    Directory of Open Access Journals (Sweden)

    Carolina Soledad Vagge

    Full Text Available El crecimiento urbano introduce permanente presión a las áreas metropolitanas. En países periféricos la demanda de energía crece a mayor velocidad que el crecimiento poblacional y la oferta, creando crisis y escasez. El objetivo principal de este trabajo es prever el impacto que tendrá la Ley 13059 de Eficiencia Energética en relación a la nueva Ordenanza de Usos del Suelo de la ciudad de La Plata y la Norma de Etiquetado de Edificios (IRAM 11900. Esta norma establece una metodología simplificada para el cálculo del nivel de eficiencia energética de las envolventes de los edificios susceptibles de ser calefaccionados. Todavía, es evidente que existe una importante falta de adecuación entre los objetivos teóricos formulados para el desarrollo de la ciudad y las conflictivas estrategias técnicas propuestas para satisfacerlos. En cuanto a la aplicación de la ley de eficiencia energética al modelo de edificio de construcción usual en La Plata, no verifica sus valores de transmitancia térmica K. Tampoco verifica el riesgo de condensación ni el coeficiente global de pérdidas G. Del mismo modo, cuando se aplica el protocolo de etiquetado de eficiencia energética que plantea la norma IRAM 11900, el edifico clasifica como H. Se puede ver que el impacto de ahorro potencial en la demanda de energía anual para calefacción, si se comienza a implementar la Ley de Eficiencia Energética sería de un 46%.

  7. Manifestaciones iniciales de la representación en el Río de la Plata: la revolución en la laboriosa búsqueda de la autonomía del individuo (1810-1812

    Directory of Open Access Journals (Sweden)

    Garavaglia, Juan Carlos

    2004-08-01

    Full Text Available Following the track of a number of studies on the early forms of representation in Iberian America, we will show how a detailed anaylisis of the first elections in the Rio de la Plata may contribute to widen our knowledge of «political representation» and «citizenship» during the two first revolutionary years. Setting off from the vacatio regis, it will be analysed in which way the Buenos Aires elites made efforts to keep the independent process under control. While this aim was achieved, the price paid for it would entangle serious consequences for the later evolution of the Rio de la Plata area.

    Siguiendo el camino trazado por una serie de estudios sobre historia de las formas primigenias de representación en América ibérica, trataremos de mostrar de qué forma un análisis pormenorizado de primeras elecciones rioplatenses puede contribuir a enriquecer nuestro acercamiento al tema de la «representación política» y de la «ciudadanía» durante los dos años iniciales post revolucionarios. Partiendo evidentemente de la «vacatio regis», tratamos de ver en este trabajo de qué modo las elites de Buenos Aires, que estaban conduciendo el único proceso que se mantuvo en forma independiente durante ese periodo, hicieron todo lo posible para que éste no escapara a su control. Efectivamente, lo consiguieron pero, a un precio que acarrearía graves consecuencias en la evolución posterior del área rioplatense.

  8. Multiphase flow and enhanced biodegradation of dense non-aqueous phase liquids. Geologica Ultraiectina (303)

    NARCIS (Netherlands)

    Langevoort, M.

    2009-01-01

    Soil and groundwater pollution by chlorinated solvents, such as tetrachloroethylene (PCE) are common throughout the industrialized world. These so called DNAPLs pose environmental health risks and sites contaminated with DNAPLs often require remediation. One of the most effective and economically

  9. Palaeoceanographic and biotic response during early Eocene extreme global warming events. Geologica Ultraiectina (328)

    NARCIS (Netherlands)

    Stap, H.L.

    2010-01-01

    Studying past intervals of abrupt global warming and massive carbon release can improve our knowledge in ways relevant to understanding future climate change. Possible paleo-analogues for future climate change are the early Paleogene hyperthermal events, such as the Paleocene-Eocene Thermal Maximum

  10. Uranium prospecting and geological favour ability in Uruguay; Prospeccion uranifera y favorabilidad geologica en el Uruguay

    Energy Technology Data Exchange (ETDEWEB)

    Goso, H [Comision Nacional de Energia Atomica, Montevideo (Uruguay)

    1981-07-01

    Uranium prospecting carried out in Uruguay since 1976 is described. On the basis of literature available and of an analysis of the large structural units pertinent to Uruguay's geology, the prospecting performed in general in the northeast of the country, and in particular in the districts of Cerro Largo and Las Canas, is described. Some information is presented on uranium favour ability in Uruguay related to sedimentary formations: Devonian (Cerrezuelo Formation) and Gondwana (San Gregorio and Tres Islas Formations), and to the Crystalline formations of the centre and Southwest (1700-2000 m.y.) and of the east and southeast (500-700 m.y.)

  11. The Middle Miocene Climate Transition in the Central Mediterranean. Geologica Ultraiectina (326)

    NARCIS (Netherlands)

    Mourik, A.A.|info:eu-repo/dai/nl/304849383

    2010-01-01

    The Middle Miocene Climate Transition (~15-13.7 Ma) is one of the major steps in Cenozoic climate evolution. The rapid expansion of the East Antarctic Ice Sheet at ~13.9 – 13.7 Ma caused important climate changes on a global scale. The aim of this PhD research has been to study the effects of the

  12. Compaction of granular carbonates under conditions relevant to diagenesis and fault sealing. Geologica Ultraiectina (332)

    NARCIS (Netherlands)

    Zhang, X.

    2010-01-01

    Carbonate reservoir rocks contain more than 60% of the world’s oil reserves and 40% of its gas reserves. The evolution of the reservoir quality, i.e. their porosity and permeability, is for a large part controlled by compaction due to pressure solution (chemical compaction). Pressure solution also

  13. Compaction of granular carbonates under conditions relevant to diagenesis and fault sealing. Geologica Ultraiectina (332)

    OpenAIRE

    Zhang, X.

    2010-01-01

    Carbonate reservoir rocks contain more than 60% of the world’s oil reserves and 40% of its gas reserves. The evolution of the reservoir quality, i.e. their porosity and permeability, is for a large part controlled by compaction due to pressure solution (chemical compaction). Pressure solution also forms an efficient mechanism of fault sealing in carbonate rocks. Moreover, during hydrocarbons production, and after injection of CO2 into carbonate reservoirs, pressure solution may lead to vertic...

  14. The Messinian Salinity Crisis: chronology and paleoenvironment in the (circum-) Mediterranean area. Geologica Ultraiectina (317)

    NARCIS (Netherlands)

    Snel, E.

    2010-01-01

    During the Messinian salinity crisis (MSC, 5.96-5.33 million years ago (Ma)), Atlantic–Mediterranean connections became stepwise restricted and interrupted. Massive evaporites were deposited in the Mediterranean Basin, which - after water levels dropped ~1km (5.59-5.5 Ma) - was partially refilled

  15. A new chronology for the late Triassic to early Jurassic. Geologica Ultraiectina (323)

    NARCIS (Netherlands)

    Deenen, M.H.L.

    2010-01-01

    Throughout geological history of life, a small number of mass extinctions have forever changed the path of evolution. The two main mechanisms that account for these dramatic events are asteroid impacts and massive volcanic eruptions of Large Igneous Provinces (LIP’s). The interplay between

  16. Redox-dependent phosphorus burial in modern and ancient marine sediments. Geologica Ultraiectina (334)

    NARCIS (Netherlands)

    Kraal, P.

    2011-01-01

    Phosphorus (P) is an essential nutrient in Earth’s biosphere that helps regulate marine primary productivity. Burial in sediments is the only pathway for long-term removal of P from the marine reservoir, the efficiency of which depends strongly on the redox state of the bottom waters;

  17. The upper mantle beneath the Gulf of California from surface wave dispersion. Geologica Ultraiectina (299)

    NARCIS (Netherlands)

    Zhang, X.

    2009-01-01

    This thesis is a study on upper mantle shear velocity structure beneath the Gulf of California. Surface wave interstation dispersion data were measured in the Gulf of California area and vicinity to obtain a 3-D shear velocity structure of the upper mantle. This work has particular significance for

  18. The immiscibles: Capillarity effects in porous media - Pore-network modelling. Geologica Ultraiectina (318)

    NARCIS (Netherlands)

    Joekar Niasar, V.

    2010-01-01

    Current theories of two-phase flow in porous media are based on the so-called extended Darcy’s law, and an algebraic relationship between capillary pressure and saturation. Both of these equations have been challenged in recent years, primarily based on theoretical works using a thermodynamic

  19. Microstructural evolution and seismic anisotropy of upper mantle rocks in rift zones. Geologica Ultraiectina (300)

    NARCIS (Netherlands)

    Palasse, L.N.

    2008-01-01

    This thesis investigates field-scale fragments of subcontinental upper mantle rocks from the ancient Mesozoic North Pyrenean rift and Plio-Pleistocene xenoliths from the active Baja California rift, in order to constrain the deformation history of the uppermost mantle. The main focus of the study is

  20. Probabilistic tomography using body wave, normal-mode and surface wave data. Geologica Ultraiectina (325)

    NARCIS (Netherlands)

    Mosca, I.

    2010-01-01

    Over the last three decades a vast number of tomographic images has been produced, but the quantitative assessment of their accuracy and uniqueness has only just started. A relatively recent technique in this direction has been made by (Trampert et al., 2004) using probabilistic tomography. It is

  1. USO DE NUEVAS METODOLOGÍAS EN LA PRÁCTICA CLÍNICA: ESTUDIO DE LA AMPLIFICACIÓN DEL ONCOGÉN HER2 CON HIBRIDACIÓN IN SITU CROMOGÉNICA Y CON PLATA (DUAL ISH EN EL CÁNCER DE MAMA

    Directory of Open Access Journals (Sweden)

    Luz Fernanda Sua

    2014-10-01

    Full Text Available Introducción: La determinación del oncogén HER2 es crítica en las pacientes que responderán al anticuerpo monoclonal humanizado Trastuzumab. La técnica de hibridación in situ cromogénica y con plata (Dual ISH ha sido exitosamente probada en la detección de la amplificación del gen HER2, un importante biomarcador del cáncer de mama que combina las ventajas de la automatización y la microscopía de luz, mejorando el flujo de trabajo en el laboratorio. Objetivos: verificar si la metodología automatizada de hibridización in situ cromogénica y con plata (Dual ISH realizada en el equipo Benchmark XT de Ventana Medical Systems® puede ser comparable con la hibridización in situ fluorescente (FISH en casos de la Fundación Valle del Lili. Metodología: Previa aprobación del Comité de Ética de la Fundación Valle del Lili, evaluamos un total de 42 casos, encontrando 98.1% con un nivel de concordancia total, tanto de la hibridización in situ fluorescente (FISH y de la inmunohistoquímica (IHQ con el ISH Dual. Determinamos un nivel de concordancia del 94.4% en el estudio del nivel de amplificación del gen HER2 por FISH y por ISH Dual. La concordancia entre la determinación de la expresión de la proteína HER2 por IHQ y por ISH Dual fue del 100%. Al evaluar nuestro coeficiente Kappa este fue de 0.97 y nuestro coeficiente de correlación intraclases en referencia con el FISH fue casi perfecto 0.85. Conclusión: nosotros observamos una reducción del tiempo de procesamiento con la técnica Dual ISH al ser una metodología automatizada (Equipo BenchMark XT de Ventana® cuando la comparamos con el protocolo FISH. La técnica Dual ISH permite la evaluación morfológica y estudia simultáneamente el centrómero del cromosoma 17 y el oncogén HER2. Esta metodología se estudia en el microscopio de luz (60x, es cuantitativa, se puede archivar y se encuentra aprobada por la Administración de Drogas y Alimentos de los Estados Unidos (FDA.

  2. Synthesis and characterization of RUM catalysts (M=SE,MO,W,SN) applied in ORR for a PEMFC fuel battery; Sintesis y caracterizacion de catalizadores RUM (M=SE,MO,W,SN) aplicados en la RRO para una pila de combustible PEMFC

    Energy Technology Data Exchange (ETDEWEB)

    Ezeta-Mejia, A.; Arce Estrada, E.M. [Instituto Politecnico Nacional, Mexico, D.F. (Mexico)]. E-mail: araceli-ezeta@hotmail.com; earce@ipn.mx

    2009-09-15

    baja temperatura y ofrecen una alta combinacion entre densidad de potencia y alta eficiencia en la conversion de energia, lo que las hace adecuadas para aplicaciones portatiles. Sin embargo, la reaccion de reduccion de oxigeno, RRO, que se lleva a cabo en el catodo de la pila, juega un papel determinante debido a que es la reaccion limitante del proceso, por lo que se requiere el empleo de electrocatalizadores mas eficientes. El electrocatalizador optimo para esta reaccion es el Pt, pero debido a su costo elevado se han tenido que buscar electrocatalizadores alternativos que conjuguen una alta actividad, estabilidad y bajo costo. Muchas investigaciones han mostrado que los catalizadores binarios base Pt tales como Pt-M (M= Co, Fe, etc.) presentan una buena actividad electrocatalitica para la RRO; otros estudios demuestran que los catalizadores base Ru (RuSe, RuSe,Mo, RuSeRh) tambien poseen una adecuada actividad para esta reaccion. En este estudio, se reporta la sintesis por aleado mecanico a diferentes tiempos de molienda (0, 20 y 40 h) de electrocatalizadores nanoparticulados de tipo RuPt{sub x}M (x=0, 0.6% y M=Se,Mo,W,Sn). Los materiales sintetizados por aleado mecanico se caracterizaron por microscopia electronica de barrido y por difraccion de rayos X, obteniendose particulas aglomeradas y dispersas entre 1 y 30 {mu}m. La caracterizacion electrocatalitica se llevo a cabo mediante las tecnicas de VC y EDR en una solucion de H{sub 2}SO{sub 4} 0.5 M a temperatura ambiente. Los sistemas presentan un orden de reaccion de 1, respecto a la RRO y una transferencia global multielectronica de 4e{sup -} para la formacion de agua. Se realizo una comparacion de la actividad electrocatalitica en presencia y ausencia de Pt, mostrando que el Pt incrementa la actividad catalitica de los materiales en al menos un orden de magnitud.

  3. State policy and monetary circulation in the Seventeenth Century Crown of Aragon: The depreciation of silver currency Política estatal y circulación monetaria en la Corona de Aragón durante el siglo XVII: la depreciación de la moneda de plata

    Directory of Open Access Journals (Sweden)

    José Antonio Mateos Royo

    2012-03-01

    Full Text Available This paper looks at the state policy applied to silver in the Spanish territories of the Crown of Aragon in the seventeenth century, where increasing demand for silver coins with a lower intrinsic than market value opened up debate on the depreciation of the domestic silver coinage. The monarchy was weaker in the Crown of Aragon than in Castile, and it was therefore obliged to negotiate these measures with the elites and institutionsof each kingdom. The paper examines the fiscal and monetary reasons forreforms, as well as the extent of political support achieved in each kingdom.Este artículo estudia la política estatal aplicada a la plata en los territorios hispánicos de la Corona de Aragón en el siglo XVII. La creciente demanda de moneda con menor valor intrínseco por el mercado abrió un debate sobre la depreciación de las monedas domésticas en la Corona. Debido a su menor poder que en Castilla, la monarquía hispánica tuvo que negociar esta medida con elites e instituciones de cada reino. El artículo analiza las razones fiscales o monetarias de estas reformas, así como el grado de apoyo político alcanzado en cada territorio.

  4. Characterization of Mexican zeolite minerals; Caracterizacion de minerales zeoliticos mexicanos

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez C, M.J

    2005-07-01

    50% of the Mexican territory is formed by volcanic sequences of the Pliocene type, which appear extensively in the northwest states (Sonora, Sinaloa, Chihuahua, Durango) and west of Mexico (Jalisco and Nayarit), in central Mexico (Zacatecas, Guanajuato, San Luis Potosi, Queretaro, Hidalgo) and south of Mexico (Guerrero, Oaxaca); therefore, it is to be expected that in our country big locations of natural zeolites exist in its majority of the clinoptilolite type. The present study was focused toward the characterization of two Mexican natural zeolite rocks presumably of the clinoptilolite and filipsite types, one of them comes from the state of Chihuahua and the other of a trader company of non metallic minerals, due that these materials are not characterized, its are not known their properties completely and therefore, the uses that can be given to these materials. In this investigation work it was carried out the characterization of two Mexican zeolite rocks, one coming from the Arroyo zone, municipality of La Haciendita, in the state of Chihuahua; and the other one was bought to a trader company of non metallic minerals. The two zeolites so much in their natural form as conditioned with sodium; they were characterized by means of X-ray diffraction, scanning electron microscopy of high vacuum and elementary microanalysis (EDS), surface area analysis (BET), thermal gravimetric analysis. To differentiate the heulandite crystalline phase of the other clinoptilolite rock, its were carried out thermal treatments. The quantification of Al, Na, Ca, K, Mg, Fe was carried out in solution, by means of atomic absorption spectroscopy and the quantity of Si was determined by gravimetry. The zeolite rocks presented for the major part the crystalline heulandite and clinoptilolite phases for the most part, and it was found that the zeolite coming from the state of Chihuahua possesses a bigger content of heulandite and the denominated filipsite it is really a zeolite clinoptilolite type. When comparing the obtained results of the elementary composition of the natural Mexican zeolites with those of zeolites clinoptilolite type from other places of the world it was found that the composition is similar as for its components and different as for its concentration. (Author)

  5. Characterization of clay minerals; Caracterizacion de minerales arcillosos

    Energy Technology Data Exchange (ETDEWEB)

    Diaz N, C.; Olguin, M.T.; Solache R, M.; Alarcon H, T.; Aguilar E, A. [Gerencia de Ciencias Basicas, Direccion de Investigacion Cientifica, Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2002-07-01

    The natural clays are the more abundant minerals on the crust. They are used for making diverse industrial products. Due to the adsorption and ion exchange properties of these, a great interest for developing research directed toward the use of natural clays for the waste water treatment has been aroused. As part of such researches it is very important to carry out previously the characterization of the interest materials. In this work the results of the mineral and elemental chemical composition are presented as well as the morphological characteristics of clay minerals from different regions of the Mexican Republic. (Author)

  6. Avaliação microbiológica de coberturas com sulfadiazina de prata a 1%, utilizadas em queimaduras Evaluación microbiológica de coberturas con sulfadiazina de plata al 1% Microbiological evaluation of 1% silver sulfadiazine dressings

    Directory of Open Access Journals (Sweden)

    Alessandra Cristina Olhan Ragonha

    2005-08-01

    Full Text Available Os objetivos foram avaliar a condição microbiológica e atividade antimicrobiana de coberturas com sulfadiazina de prata a 1%, utilizadas em queimaduras, preparadas e estocadas de 12 a 60 horas antes do uso. A avaliação microbiológica foi realizada por semeadura de três alíquotas preparadas em diferentes tempos no meio de cultura Letheen Bloth (Difco e incubadas a 32-35°C, durante 20 dias. A atividade antimicrobiana foi avaliada pela difusão de uma alíquota da cobertura frente às cepas hospitalares com incubação em temperatura ambiente até 37°C, por 18-24 horas. As três alíquotas de tempos 12, 36 e 60 horas foram negativas. Quanto à atividade antimicrobiana, observou-se "halo" de inibição de 2,25mm para S. aureus, 2,65mm para P. aeruginosa e 2,95mm para E. coli. Coberturas com sulfadiazina de prata a 1% podem ser pré-preparadas e armazenadas com segurança e têm como vantagens redução do tempo dos profissionais na realização do curativo e, conseqüentemente, da exposição do paciente.La finalidad fue evaluar la condición microbiológica y la actividad antimicrobiana de coberturas con sulfadiazina de plata al 1%, preparadas y almacenadas 12-60 horas antes del uso. La evaluación microbiológica fue realizada por la siembra de tres proporciones preparadas en diferentes tiempos en el medio de cultivo Letheen Broth (Difco y incubada a 32-35°C, durante 20 días. La actividad antimicrobiana fue evaluada por la difusión de una proporción ante las cepas hospitalarias, inicialmente con incubación en temperatura ambiente y después en 370C por 18-24 horas. Todos los tres cultivos de 12, 36 y 60 horas fueron negativos. Cuanto a la actividad antimicrobiana, las zonas de inhibición fueron de 2,25mm para S.aureus, 2,65mm para P. aeriginosa y 2,95mm para E coli. Coberturas con sulfadiazina de plata al 1% pueden ser preparadas y almacenadas con seguridad, y tiene como beneficio la reducción del tiempo de los profesionales en la

  7. ESTUDIO DE LAS CONDICIONES DE CALIDAD DE VIDA EN LOS ESPACIOS URBANOS Y PERIURBANOS DEL SUR DE LA CIUDAD DE MAR DEL PLATA (ARGENTINA A PARTIR DE LA ELABORACIÓN Y ANÁLISIS ESPACIAL DE UN ÍNDICE SINTÉTICO SOCIOAMBIENTAL

    Directory of Open Access Journals (Sweden)

    Laura Zulaica

    2008-01-01

    Full Text Available Las ciudades, entendidas como una forma particular de relación sociedad-naturaleza, refl ejan problemas socioambientales que influyen diferencialmente en la calidad de vida de la población urbana y periurbana. El presente estudio, desarrollado en un sector situado al sur del tejido urbano de Mar del Plata, plantea como objetivo la elaboración de un índice de calidad de vida que incorpora en su concepción aspectos ambientales, denominado Índice de Calidad de Vida Socioambiental (ICVSA. La construcción del ICVSA, que considera los radios censales como unidad de referencia espacial, surge de la integración de indicadores sociales y ambientales, mediante la aplicación de un procedimiento metodológico desarrollado para ese fin. El análisis de los indicadores agrupados en cinco dimensiones (educación, salud, habitacional, pobreza y ambiental, demostró la existencia de una clara diferenciación entre el sector urbano y periurbano, manifestando este último una mayor heterogeneidad espacial y situaciones más críticas de calidad de vida socioambiental. Asimismo, la aplicación de una técnica de correlación espacial geográfi ca permitió profundizar en la distribución territorial del índice. De esta manera, se detectaron zonas, con un alto nivel de detalle, que requieren medidas para afrontar sus problemáticas socioambientales existentes y emergentes.

  8. Efecto de inhibidores de etileno en la longevidad floral del clavel (Dianthus caryophyllus L. como probables sustitutos del tiosulfato de plata (STS Effect of ethylene inhibitors in extending the vase life of camation iDianthus caryophyllus L. cut flowers as substitutes of silver thiosulfate (STS

    Directory of Open Access Journals (Sweden)

    Cubillos Eliberto

    2001-12-01

    Full Text Available En Colombia el sector de flores de corte para exportación se
    ha constituido en un renglón de gran importancia económica.
    Sin embargo, los altos costos de producción y los bajos precios han hecho que la rentabilidad de esta industria haya
    decaído en los últimos años. El tiosulfato de plata (STS es
    uno de los productos más empleados en poscosecha de flores, pero en la actualidad es visto como un posible contaminante ambiental. Con el objetivo de comparar la respuesta de productos tradicionales en poscosecha, cuyo ingrediente principal es el ion Ag", con otros de mayor degradabilidad, se llevó a cabo un ensayo con clavel estándar de la variedad 'Nelson '. Los tallos florales fueron cosechados en cultivo bajo condiciones de invernadero en una finca comercial de la Sabana de Bogotá, seleccionados y sometidos a diferentes soluciones de poscosecha para prolongar la vida en florero. Posteriormente, se les realizó la simulación de transporte durante un periodo de diez días y, en seguida, llevados al laboratorio de Fisiología de Cultivos de la Universidad Nacional de Colombia, Sede Bogotá, en donde, se monto el ensayo para realizar las respectivas mediciones. En el laboratorio, los tallos se mantuvieron hidratados en agua destilada, en condiciones de 12 h de fotoperiodo (luz artificial de 6 a.m. a 6 p.m. y con ventilación de 30 min en las horas de la mañana para evitar la acumulación del etileno. Las condiciones ambientales promedio del laboratorio fueron de 19°C y H. R. de 75%. Los productos comerciales empleados fueron Tiosulfato de Plata (STS elaborado en la finca, l-Metilciclopropano (1-MCP, Chrysal AVB, Chrysal EVB, Florissima 125, Florissima 135 y Florissant 100. Los mejores resultados en longevidad floral se obtuvieron con la combinación de 1-MCP + Florissima 135 (22 días, Florissima 125 (21, 7 días y STS finca (21 ,5 días. Se comprobó que algunos productos que no contienen el ion Ag (Florissima 135 y

  9. Spectral analysis of uneven time series of geological variables; Analisis espectral de series temporales de variables geologicas con muestreo irregular

    Energy Technology Data Exchange (ETDEWEB)

    Pardo-Iguzquiza, E.; Rodriguez-Tovar, F. J.

    2013-06-01

    In geosciences the sampling of a time series tends to afford uneven results, sometimes because the sampling itself is random or because of hiatuses or even completely missing data or due to difficulties involved in the conversion of data from a spatial to a time scale when the sedimentation rate was not constant. Whatever the case, the best solution does not lie in interpolation but rather in resorting to a method that deals with the irregular data. We show here how the use of the smoothed Lomb-Scargle periodogram is both a practical and efficient choice. We describe the effects on the estimated power spectrum of the type of irregular sampling, the number of data, interpolation, and the presence of drift. We propose the permutation test as being an efficient way of calculating statistical confidence levels. By applying the Lomb-Scargle periodogram to a synthetic series with a known spectral content we are able to confirm the validity of this method in the face of the difficulties mentioned above. A case study with real data, including hiatuses, representing the thickness of the annual banding in a stalagmite, is chosen to demonstrate an application using the statistical and physical interpretation of spectral peaks. (Author)

  10. Dissolution of biogenic silica: Roles of pH, salinity, pressure, electrical charging and reverse weathering. Geologica Ultraiectina (302)

    NARCIS (Netherlands)

    Loucaides, S.

    2009-01-01

    The recycling of biogenic silica (bSiO2) produced by diatoms is a vital process sustaining a significant fraction of primary production in the oceans. The efficiency with which bSiO2 dissolves controls the availability of nutrient silicon in the water column, and modulates the export of organic

  11. Reconstruction of the Arctic Ocean environment during the Eocene Azolla interval using geochemical proxies and climate modeling. Geologica Ultraiectina (331)

    NARCIS (Netherlands)

    Speelman, E.N.

    2010-01-01

    With the realization that the Arctic Ocean was covered with enormous quantities of the aquatic floating fern Azolla 49 Myrs ago, new questions regarding the Eocene conditions facilitating these blooms arose. This dissertation describes the reconstruction of paleo-environmental conditions

  12. The global marine phosphorus cycle: Response to climate change and feedbacks on ocean biogeochemistry. Geologica Ultraiectina (329)

    NARCIS (Netherlands)

    Tsandev, I.

    2010-01-01

    This thesis focuses on the marine phosphorus (P) cycle and its response to changing environmental conditions, particularly those associated with glacial-interglacial cycles of the late Pleistocene and Ocean Anoxic Events in the Cretaceous. From a box model of the ocean phosphorus, organic carbon and

  13. Coupled models of free methane gas and anaerobic oxidation of methane : from core to regional scales. Geologica Ultraiectina (339)

    NARCIS (Netherlands)

    Mogollón, J.M.

    2011-01-01

    Methane is a potent greenhouse gas that is produced in marine sediments containing high amounts of degrading organic carbon. It is therefore not surprising that marine sediments contain vast amounts of methane (500-5000 gigatons) present in dissolved (aqueous), free gas (gaseous), and solid

  14. Seismic and geological characteristics of the Gioia Tauro site; Caratterizzazione sismica e geologica del sito di Gioia Tauro

    Energy Technology Data Exchange (ETDEWEB)

    Capocecera, P; Carillo, A; Fels, A; Gorelli, V; Iacurto, O; Marzi, C; Musmeci, F; Paciello, A; Vitiello, F [ENEA - Dipartimento Protezione Ambientale e Salute dell' Uomo, Centro Ricerche Energia, Casaccia (Italy)

    1990-01-15

    ENEA is developing some important projects for the design and installation of local seismic arrays. This research project, named 'the Gioia Tauro Project', covers design and installation of a local accelerometric network having special characteristics in the area where some earthquakes might occur in the next future. Aim of the network is to collect information on the variability of the ground motion characteristics both on the ground surface and at different depths of soft soil deposits. (author)

  15. Caracterização geologica e geofisica da estrutura de impacto Domo de Vargeão, SC

    OpenAIRE

    Cesar Kazzuo Vieira

    2009-01-01

    Resumo: O Domo de Vargeão (SC), com 12,4km de diâmetro, é uma estrutura de impacto do tipo complexa parcialmente erodida, formada sobre os derrames vulcânicos da Formação Serra Geral, na bacia do Paraná. Em seu interior afloram, de forma anômala, arenitos atribuídos ás formações Botucatu e Pirambóia, normalmente situados a cerca de 1km abaixo da superfície atual. O objetivo principal deste estudo foi a caracterização geológica e geofísica do Domo de Vargeão, em superfície e em subsuperfície, ...

  16. Mining reservation X IV. Present state of geological researchs; Reserva Minera XIV estado actual de las investigaciones geologicas

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Rifas, C; Tabo, F

    1991-07-01

    The mining reservation includes the aerial photo of Cerro Chato, Valentines, Chileno and Rossell y Rius. The main objective of this work is the regional metals characterization in special basic metals such as gold.

  17. Structure and properties of fluid-filled grain boundaries under stress in geological materials. Geologica Ultraiectina (290)

    NARCIS (Netherlands)

    van Noort, R.

    2008-01-01

    Two of the three processes making up the deformation mechanism of intergranular pressure solution, being dissolution and diffusion, take place in the grain boundary fluid phase. Hence, the structure and physical properties of wet grain boundaries under stress can be expected to influence the

  18. Geological uncertainties in the estimates of royalties; As incertezas geologicas na previsao de receitas de 'royalties'

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Jose Otavio; Chaves, Hernani A. Fernandes [Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Dept. de Estratigrafia e Paleontologia. Geologia do Petroleo, Gas Natural e Carvao; Fundacao Carlos Chagas Filho de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ), Rio de Janeiro, RJ (Brazil); Centro de Informacoes de Petroleo e Gas Natural (CIPEG), Rio de Janeiro, RJ (Brazil)

    2008-07-01

    In the economic analysis of oil basins, several variables are involved, such as: reserves, exploration risk, technology, production, price, among others. In the present we will focus on the variables reserves, production and prices. The geologic uncertainties in the analysis of petroleum basins start with the quantification of the reserves, which present diverse classifications and varied concepts. Within the geologic uncertainties, the production is one of the variables which influence the payment of royalties, due to the fluctuations that occur in the production cycle during the useful life of a producing field. To arrive at the production phase, the production chain indicates exploration, evaluation and development, stages which must be overcome so the final objective can be reached, which is the extraction of oil. The peculiar characteristics of the industry and the production chain, composed of several phases, besides the political and financial risk inherent to the petroleum activity, mean that high investments are necessary in order to maintain increasing production to meet the consumption requirements. First the reserves, then the development, exploration and, finally, the production are evaluated. The price is one of the components in the calculation of oil royalties, being influenced by diverse internal and external factors, which will be shown during the course of this work. (author)

  19. Dynamics of subduction and continental collision: Influence of the nature of the plate contact. Geologica Ultraiectina (284)

    NARCIS (Netherlands)

    De Franco, R.

    2008-01-01

    At convergent plate boundaries, the properties of the actual plate contact are important for the overall dynamics. Convergent plate boundaries both mechanically decouple and link tectonic plates and accommodate large amounts of strain. We investigate two fundamental physical states of the subduction

  20. Composition and Vacancy Flux Effects in Tracer Diffusion in Silver-Gold Alloys; Effets de la Composition et du Flux de Lacunes sur la Diffusion des Indicateurs dans les Alliages d'Or et d'Argent; Vliyanie sostava i potoka vakansij pri diffuzii indikatorov v splavakh serebra i zolota; Efectos de la Composicion y del Flujo de Huecos Sobre la Difusion de Indicadores en Aleaciones Plata-Oro

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, R. O.; Slifkin, L. [University of North Carolina, Chapel Hill, NC (United States)

    1966-02-15

    'interface a quelques microns pres. Les resultats obtenus jusqu'en fevrier 1965 indiquent que les deplacements du centre de la distribution de l'or indicateur sont d'environ 20 microns vers l'extremite riche en argent. (author) [Spanish] Los estudios de autodifusion en aleaciones plata-oro muestran que las energias de activacion disminuyen monotonamente al aumentar la concentracion del segundo metal. Las teorias basadas en los estados correspondientes en los efectos del tamafio o en los calores de solucion, no alcanzan a explicar dichos resultados; en cambio, la ampliacion introducida por LeClaire en la teoria electrostatica de Lazarus brinda una concordancia semicuantitativa. La disminucion de los factores preexponenciales al aumentar la concentracion de oro indica que la entropia de la migracion de huecos decrece en forma proporcional a la composicion, a razon de 1,5 R, desde plata pura hasta oro puro. Para ambos indicadores a una temperatura fija, el coeficiente de difusion D, en funcion de la composicion, presenta un minimo aplanado. Utilizando estos datos para verificar las teorias sobre la interaccion huecos-impurezas, solo las de Manning y Lidiard dan resultados satisfactorios y concordantes. El agregado del metal mas movil -plata- al menos movil -oro- produce en la practica una disminucion de D para ambos indicadores; el analisis indica que la presencia de un atomo de plata junto a un hueco y a un atomo de oro reduce en un factor de 0,4 aproximadamente la frecuencia del salto correspondiente a este ultimo. La presencia de un minimo aplanado en la curva representativa de D en funcion de la composicion, permite investigar el efecto del flujo de huecos sobre la difusion del indicador. Se prepara un par de Kirkendall con composiciones desplazadas simetricamente respecto del minimo. La interfase contiene una capa delgada de indicador de oro y esta marcada con particulas finas de oxido de hafnio radiactivo. Durante el recocido por difusion, el flujo de huecos produce un

  1. Polymerization of Ethylene in Aqueous Silver-Salt Solution by Cobalt-60 Gamma Radiation; Polymerisation de l'ethylene dans une solution aqueuse de sel d'argent par des rayons gamma du cobalt-60; Polimerizatsiya ehtilena v vodnom rastvore serebryanoj soli pod dejstviem gamma-izlucheniya kobal'ta-60; Polimerizacion del etileno en solucion acuosa de sales de plata por los rayos gamma del cobalto-60.

    Energy Technology Data Exchange (ETDEWEB)

    Rosinger, S.; Mullner, S. [Farbwerke Hoechst AG, Hoechst (Germany)

    1963-11-15

    reagissant pour 100 eV d'energie absorbee) de 0,6 x 10{sup 5} pour le systeme global et superieure a 0,5 x 10{sup 6} pour l'ethylene dissoute. La formation de polymeres augmente lorsque la pression de l'ethylene et la concentration du sel d'argent croissent. La solution de sel d'argent peut etre reutilisee sans que le rendement diminue. La reaction est inhibee par des traces d'oxygene. Le rendement en polymere est proportionnel a la dose absorbee si l e debit de dose est constant. La variation du rendement en fonction du debit de dose J est egale a J{sup 0,5-0,6}. La temperature optimum se situe entre 20 et 30{sup o}C, Au-dessous de 0{sup o}C, la reaction ne se produit pas. La vitesse d'agitation n'a aucune influence sur le rendement. Le poids specifique des produits est d'environ 0,94g /cm{sup 3}; les points de fusion se situent entre 126 et 131{sup o}C. Des etudes sur l'absorption infrarouge n'ont revele aucune double liaison C-C ni aucun groupe C-O-H ou C=O; on a decele un petit nombre de liaisons C-O-C. La proportion de groupes methyles est de 0,3%; les polymeres ont probablement de longues chaines ramifiees et leur vicsocite varie entre 5 et 10. (author) [Spanish] El etileno, las mezclas de etileno y propeno y el propeno polimerizan por irradiacion en solucion acuosa de sales de plata a presiones moderadas. Mientras que el propeno forma aceites y ceras, el etileno da origen a polimeros solidos de elevado peso molecular. Los rendimientos obtenidos fueron superiores a 25g de polietileno por litro y hora. Para una intensidad de dosis de 7,1 x 10{sup 3} rad/h, esto corresponde a un valor G (numero de moleculas que reaccionan por 100 eV de energia absorbida) de 0,6 x 10{sup 5} por el sistema global y superior a 0,5 x 10{sup 6} para el etileno disuelto. La formacion del polimero aumenta con la presion del etileno y la concentracion de las sales de plata. La solucion de sales de plata puede volverse a utilizar sin disminucion del rendimiento. La reaccion es inhibida por

  2. AISLAMIENTO Y CARACTERIZACION DE UNA LEVADURA FLOCULANTE PARA PRODUCIR ETANOL DEL BANANO DE RECHAZO

    Directory of Open Access Journals (Sweden)

    CARLOS GUEVARA-BRAVO

    Full Text Available Fue aislada y caracterizada una cepa de levadura Saccharomycescerevisiae LEG-06, con características floculantes para fermentar jugo de banano extraído bajo condiciones básicas. Los rendimientos de etanol fueron comparados con levaduras comerciales y además fueron evaluados los efectos del pH y del agente neutralizante. Adicionalmente se evaluó el efecto sobre la eficiencia de 10 fermentaciones sucesivas usando la misma levadura. Finalmente, se escaló la fermentación a 40 L en reactor tubular con agitación mecánica y se determinaron los parámetros cinéticos de la levadura. Las condiciones ideales fueron: pH 5,5 utilizando ácido cítrico como neutralizante, 23,8 g/L de levadura, 14,5°Brix. La eficiencia estuvo entre 82-84% y el pH óptimo de floculación entre 5,5 y 6,0. La concentración de etanol obtenido en las mejores condiciones alcanzó el 7,5%. Estos resultados demuestran la levadura como la metodología usada, presentan las características adecuadas y deseadas para desarrollar un proceso a nivel de planta piloto para la producción de etanol a partir de banano de rechazo.

  3. Characterization of radioactive orphan sources by gamma spectrometry; Caracterizacion de fuentes huerfanas radiactivas por espectrometria gamma

    Energy Technology Data Exchange (ETDEWEB)

    Cruz W, H., E-mail: wcruz@ipen.gob.pe [Instituto Peruano de Energia Nuclear (PGRR/IPEN), Lima (Peru). Planta de Gestion de Residuos Radiactivos

    2013-07-01

    The sealed radioactive sources are widely applicable in industry. They must have a permanent control and must be registered with the Technical Office of the National Authority (OTAN). However, at times it has identified the presence of abandoned sealed sources unknown to the owner. These sources are called 'orphan sources'. Of course these sources represent a high potential risk because accidents can trigger dire consequences depending on your activity and chemical form in which it presents the radioisotope. This paper describes the process and the actions taken to characterize two orphan radioactive sources from the smelter a Aceros Arequipa. For characterization we used a gamma spectrometry system using a detector NaI(Tl) 3″ x 3″ with a multichannel analyzer Nucleus PCA-II. The radioisotope identified was cesium - 137 ({sup 137}Cs) in both cases. Fortunately, the sources maintained their integrity would otherwise have generated significant pollution considering the chemical form of the radioisotope and easy dispersion. (author)

  4. Synthesis and characterization of poly iodine anilines by plasma; Sintesis y caracterizacion de poliyodoanilinas por plasma

    Energy Technology Data Exchange (ETDEWEB)

    Enriquez P, M A

    2003-07-01

    The polymers and organic materials present a numberless quantity of applications. However, it has not been but until recent times that it has been found that some of these materials can possess semiconductor properties. This has generated a great interest for the investigation in the area of semiconductor polymers. The poly aniline (Pan) it is one of the main semiconductor polymers because their electric properties change depending on the doping and of the state of oxidation to the one the molecules are subjected. The synthesis of this material has been carried out by means of chemical oxidation or electrochemistry. In this work a study is presented on the formation of poly aniline polymers with halogens chemically united to the aniline ring, poly(m-iodine aniline) (m-PAnI) and poly(m-chloroaniline) (m-PAnCI) for plasma. The plasma is generated by means of discharges of splendor with an r f amplifier to 13.5 MHz to drops pressures (10{sup -2} mbar). The synthesized polymers were obtained in form of thin film in the walls of the reactor and in the substrate introduced in the one. The electric properties of the polymers were evaluated in function of the time of reaction. Also, the conductivity of the polymers was compared synthesized in this work with reported data of synthesized poly aniline and doped with iodine for plasma. The highest values in conductivity are obtained in the poly aniline where the halogens are chemically connected to the ring that if it is doped with iodine. The atomic proportion in the surface of the polymers was analyzed by dispersive energy spectroscopy with which is deduced that the halogens come off of the molecules of the monomers or of the polymer in formation and that the atoms of iodine get lost more easily than those of chlorine. Other techniques that were used to characterize to the poly aniline were scanning electron microscopy, infrared spectroscopy, thermal gravimetric analysis and X-ray diffraction. The results are presented in function of the time of reaction that is one of the variables that there is shown to be very significant to promote inter crossing and ramification in the materials synthesized by plasma. The content of this thesis work is presented in six chapters: in the Chapter 1 the generalities of the polymers are described as their classification and the different polymerization techniques, as well as some concepts on the plasma, polymerization for plasma and like it is generated. In the Chapter 2 the importance is described that has the poly aniline like semiconductor material in its pure form and doped. Also the mechanism of electric conduction that is carried out in the polymers is discussed. The Chapter 3 narrate the theoretical foundation of the analytic techniques that were used to characterize to the synthesized polymers. Also, the experimental arrangement is explained that was used in the measurement of the electric conductivity of the polymers. In the Chapter 4 the synthesis of the polymers is described which includes the m-iodine aniline synthesis and m-chloroaniline for plasma and the chemical conditions under which were carried out the syntheses. The results that they were obtained when characterizing the polymers for: measurement of thickness, scanning electron microscopy, infrared spectroscopy, X-ray diffraction, thermogravimetry and electric conductivity are presented in the Chapter 5 of this work. At the end the conclusions of this work are presented. (Author)

  5. Generation and characterization of microcracks in structural materials; Generacion y Caracterizacion de Microgrietas en materiales estructurales

    Energy Technology Data Exchange (ETDEWEB)

    Menendez, E.; Frutos, J. de

    2012-07-01

    In this paper, we study how to generate and accelerate, expansive phenomena within cementitious composites, considering elements of addiction using both fly ash and slag. We present results of monitoring of these processes from the beginning and characterize chemical, microstructural, and crystallographic by X-ray diffraction, backscattering electron microscopy, X-ray dispersive energy and mercury porosimetry. These data are supplemented with values of mechanical behavior of materials to determine their functionality. As a result of these studies, we propose a model for the generation and progression of microcracks for each alteration processes studied. (Author) 7 refs.

  6. Sintesis y caracterizacion microestructural de aluminas obtenidas a partir de un precursor no convencional

    Science.gov (United States)

    Fillali, Laila

    The rampant success of quantum theory is the result of applications of the 'new' quantum mechanics of Schrodinger and Heisenberg (1926-7), the Feynman-Schwinger-Tomonaga Quantum Electro-dynamics (1946-51), the electro-weak theory of Salaam, Weinberg, and Glashow (1967-9), and Quantum Chromodynamics (1973-); in fact, this success of 'the' quantum theory has depended on a continuous stream of brilliant and quite disparate mathematical formulations. In this carefully concealed ferment there lie plenty of unresolved difficulties, simply because in churning out fabulously accurate calculational tools there has been no sensible explanation of all that is going on. It is even argued that such an understanding is nothing to do with physics. A long-standing and famous illustration of this is the paradoxical thought-experiment of Einstein, Podolsky and Rosen (1935). Fundamental to all quantum theories, and also their paradoxes, is the location of sub-microscopic objects; or, rather, that the specification of such a location is fraught with mathematical inconsistency. This project encompasses a detailed, critical survey of the tangled history of Position within quantum theories. The first step is to show that, contrary to appearances, canonical quantum mechanics has only a vague notion of locality. After analysing a number of previous attempts at a 'relativistic quantum mechanics', two lines of thought are considered in detail. The first is the work of Wan and students, which is shown to be no real improvement on the iisu.al 'nonrelativistic' theory. The second is based on an idea of Dirac's - using backwards-in-time light-cones as the hypersurface in space-time. There remain considerable difficulties in the way of producing a consistent scheme here. To keep things nicely stirred up, the author then proposes his own approach - an adaptation of Feynman's QED propagators. This new approach is distinguished from Feynman's since the propagator or Green's function is not obtained by Feynman's rule. The type of equation solved is also different: instead of an initial-value problem, a solution that obeys a time-symmetric causality criterion is found for an inhomogeneous partial differential equation with homogeneous boundary conditions. To make the consideration of locality more precise, some results of Fourier transform theory are presented in a form that is directly applicable. Somewhat away from the main thrust of the thesis, there is also an attempt to explain, the manner in which quantum effects disappear as the number of particles increases in such things as experimental realisations of the EPR and de Broglie thought experiments.

  7. Sampling and characterization of radioactive liquid wastes; Muestreo y caracterizacion de desechos liquidos radiactivos

    Energy Technology Data Exchange (ETDEWEB)

    Zepeda R, C.; Monroy G, F.; Reyes A, T.; Lizcano, D. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Cruz C, A. C., E-mail: carla.zepeda@inin.gob.mx [SEP, Instituto Tecnologico de Orizaba, Av. Oriente 9, Col. Emiliano Zapata, 94320 Orizaba, Veracruz (Mexico)

    2017-09-15

    To define the management of radioactive liquid wastes stored in 200 L drums, its isotope and physicochemical characterization is essential. An adequate sampling, that is, representative and homogeneous, is fundamental to obtain reliable analytical results, therefore, in this work, the use of a sampling mechanism that allows collecting homogenous aliquots, in a safe way and minimizing the generation of secondary waste is proposed. With this mechanism, 56 drums of radioactive liquid wastes were sampled, which were characterized by gamma spectrometry, liquid scintillation, and determined the following physicochemical properties: ph, conductivity, viscosity, density and chemical composition by gas chromatography. 67.86% of the radioactive liquid wastes contains H-3 and of these, 47.36% can be released unconditionally, since it presents activities lower than 100 Bq/g. 94% of the wastes are acidic and 48% have viscosities <50 MPa s. (Author)

  8. Background characterization in a liquid scintillation spectrometer; Caracterizacion del fondo de un espectrometro de centelleo liquido

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Barquero, L.; Los Arcos, J.M.; Jimenez de Mingo, A.

    1995-07-01

    An alternate procedure for background count rate estimation in a liquid scintillation spectrometer is presented, which does not require to measure a blank with similar composition, volume and quench, to the problem sample. The procedure is based on a double linear parameterization which was obtained from a systematic study of the background observed with glass vials, in three different windows, 0 - 20 KeV, 0 - 800 KeV and 0 - 2 MeV, for volume between 2 and 20 mi of three commercial scintillators, Hisafe II, Ultima-Gold and Instagel, and quenching degree in the interval equivalent to 50% - 3% tritium efficiency. This procedure was tested with standard samples of 3H, and led to average discrepancies less than 10% for activity {>=}0,6 Bq, against conventional methods for which the discrepancies are twice on average. (Author) 10 refs.

  9. CARACTERIZACION DE UN MINERAL DE COBRE EN ARGENTINA PARA LA PRODUCCION DE MATTE.

    Directory of Open Access Journals (Sweden)

    VANESA BAZÁN

    2011-01-01

    Full Text Available Argentina, posee minerales cuyas reservas la potencian para constituirse en un fuerte abastecedor regional. Actualmente, se han realizado proyectos de exploraciones y explotación de minerales de cobre que poseen una ley entre 0,5% y 0,8% generalmente libre de impurezas como Sb, As, Pb, Bi y Hg. [1, 2, 3, 4] Este hecho indicaría que puede existir un gran potencial para el desarrollo de la pirometalurgia del cobre, dado que hasta el momento no existen avances en este sentido. En este trabajo se presentan resultados de un estudio realizado sobre un mineral de baja ley de Cu, en el cual se identifi can sus fases mediante microscopía óptica, ensayos de fl otación contemplando diferentes condiciones, con el objetivo de obtener concentrados de distintas calidades. Finalmente, para comprender aspectos del proceso de obtención del cobre se realiza una simulación del proceso de fusión en el horno fl ash basado en balances de masa y energía.

  10. CARACTERIZACION DE LA PRODUCTIVIDAD PESQUERA DESARROLLADA EN LA COCHA JACINTO, RESERVA NACIONAL PACAYA SAMIRIA

    Directory of Open Access Journals (Sweden)

    Javier del Águila Chávez

    2011-12-01

    Full Text Available El presente estudio describe las características de la productividad pesquera por un periodo de cuatro años  en la “cocha Jacinto”. La “cocha Jacinto” está ubicada en la Reserva Nacional Pacaya Samiria (RNPS (coordenadas UTM E 0623314 y N 9495909, Loreto, Perú. Los datos fueron recolectados a partir de fichas de registro de pesca llenadas por el propio pescador. La productividad pesquera se estimó por el número de individuos con mayor captura, captura por unidad de esfuerzo (CPUE  y biomasa bruta según consumo (BBC. Los datos fueron digitados y analizados utilizando el programa Microsoft Excel v. 2000.Durante el periodo 2006 – 2009: a Los individuos con mayor captura fueron la “Carachama” (Fam. Loricaridae, “sardina” (Fam. Characidae, “Fasaco” (Fam. Erythrinidae y “Shuyo” (Fam. Erythrinidae; b con respecto a la CPUE: 0.16 kg/hora,  0.15 kg/hora, 0.38 kg/hora y 0.65 kg/hora; y c la BBC osciló entre 56.85 kg, 45.81 kg, 202.04 kg y  81.63 kg, según respectivo año. Las diferencias de la CPUE indican un probable incremento de la producción pesquera. Sin embargo se necesitan mayores estudios para evaluar las dinámicas de la producción pesquera y evaluar factores sociales.  Limitación a considerar es la calidad de los datos recolectados

  11. CARACTERIZACION MOLECULAR DE LOS HAPIOGRUPOS DE DNA MITOCONDRIAL EN LA ENFERMEDAD CELIACA

    OpenAIRE

    PARADA DAZA, ALEJANDRA CRISTINA

    2010-01-01

    La enfermedad celiaca (EC), es un desorden autoinmune intestinal crónico con un fuerte componente genético, asociado a genes HLA-002 o HLA-008. La prevalencia en Europa de la EC se estima en el 1%, sin embargo en América del Sur no hay una estimación de la prevalencia de EC y no se conoce si la étina se relaciona con la baja frecuencia de la enfermedad o simplemente es el reflejo del subdiagóstico en la zona. El análisis de la presencia de genes nativos se puede realizar a través de la búsque...

  12. Synthesis and characterization of porous calcium phosphate; Sintesis y caracterizacion del fosfato de calcio poroso

    Energy Technology Data Exchange (ETDEWEB)

    Granados C, F.; Serrano G, J.; Bonifacio M, J. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico)]. e-mail: fgc@nuclear.inin.mx

    2007-07-01

    The porous calcium phosphate was prepared by the continuous precipitation method using Ca(NO{sub 3}){sub 2}.4H{sub 2}O and NH{sub 4}H{sub 2}PO{sub 4} salts. The synthesized material was structurally and superficially characterized using the XRD, BET, IR TGA and SEM techniques. The obtained inorganic material was identified as calcium phosphate that presents a great specific area for what can be efficiently used as adsorbent material for adsorption studies in the radioactive wastes treatment present in aqueous solution. (Author)

  13. Characterization of the detectability of an intraoperative minigammacamera; Caracterizacion de la detectabilidad de una minigammacamara intraoperatoria

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Jimenez, J.; Nunez Martinez, L. M. R.; Morillas Ruiz, J.; Pizarro Trigo, F.; Crespo Mesa, S.; Ros Lorda, M.A.

    2011-07-01

    Screening of the sentinel node is a technique which is widely used in Nuclear Medicine Services for its ability to reduce the morbidity associated lymphadenectomy. This intervention is particularly important that accurate detection of the probe uptake, The aim of this study is to evaluate all the factors that influence the detection image by introducing the contributions of intraoperative minigammacamera systems. (Author)

  14. Caracterizacion de musculos artificiales con capacidades sensores/actuadores e intercambio mayoritario de cationes

    Science.gov (United States)

    Valero Conzuelo, Laura Luz

    Over the past decade scientific research has been looking for new biomimetic materials able to imitate human organs behaviour, in such a way that is possible to apply them on different technologies: low cost ones, scalable ones, low energy consumption ones and on those with high potentialities in areas such as health, robotics, artificial nerves and muscles, among others. Most of the studied materials mimic the extracellular matrix (ECM) of living cells and its physical functions. Now, and for the first time, conducting polymers, and other electroactive materials exchange ions and water through electrochemical reactions: the material becomes a dense electroactive gel. The content of mentioned gel and the reactions happening in it mimic, by the first time in the history of science, the composition (in its simplest expression) and reactions taking place in the reactive intracellular matrix of the functional cells of living beings. During the chemical reactions (oxidation or reduction) the gel relative composition (polymer-ion-water) shifts, in a reversible way, by several orders of magnitude. Along with it several composition-dependent properties of the material change simultaneously. The reversible variation of the material volume driven by the reactions mimics the natural muscles behaviour: artificial polymeric muscles, or polymeric electrochemical actuators, based on this property are being developed. With the material composition the consumed energy change as a function thermal, chemical or mechanical conditions. This fact is used for the development of sensors and biosensors. The material volume and the material potential shift, simultaneously, during the reaction. Here the possibility to develop dual sensing-actuators is explored: two elements working concurrently in the same, physically uniform, device mimicking haptic muscles. In this thesis the electrochemical synthesis of thick polypyrrole/DBS films is described. The electrochemical behaviour of the polymer film, used as a self-supported electrode, is characterized assuming the exchange of cations during its oxidation/reduction. For the electrochemical characterization of biomimetic films of polypyrrole/DBS, different electrochemical techniques are used and under different experimental conditions with the view to understanding the sensing potentialities of the material reactions. The study and electrochemical characterization of the motion of pPy/DBS//tape bilayer bending actuators corroborates that the reaction is driven by the expulsion of cations from the conducting polymer to the electrolyte during oxidation and its entrance during reduction, in the full potential range studied. The actuator is a faradaic device controlled by the electrochemical reaction driving the movement: the rate of the angular movement is a linear function (easy control of the velocity) of the applied current and the described angle by the displacement is a linear function of the consumed charge (it also provides another easy control of the displacement). The evolution of the muscle potential and that of the consumed electrical energy during the reaction senses the energetic working conditions: chemical energy (electrolyte concentration), thermal energy (working temperature) or electric energy (applied current). The polymeric motor senses, while working, environmental conditions. The sensing calibration curves were attained for the different sensors. They have been constructed and characterized triple-layer artificial muscles pPy/DBS//Tape//pPy/DBS, corroborating again the exchange of cations during the reaction, the faradic nature of the device and the ability of the device to sense, while moving, its environmental working conditions mimicking natural haptic muscles. The actuator (current and charge) and sensing (muscle potential and involved energy) signals are simultaneously present in only two connecting wires, mimicking brain-muscle intercommunication. The study of polymeric materials with cationic and/or ionic exchange opens the possibility of working in a future, using also anion-exchange materials, to develop new soft, wet, biomimetic and multifunctional tools and robots. Ionic, chemical, thermal and mechanical signals can be transformed into electrical ones and the involved information is transported using just two wires, simplifying in that way their connection to computers: the design of devices and robots having them heralds a more efficient technology.

  15. CARACTERIZACION DE LA PRODUCTIVIDAD PESQUERA DESARROLLADA EN LA COCHA JACINTO, RESERVA NACIONAL PACAYA SAMIRIA

    Directory of Open Access Journals (Sweden)

    Javier del Águila Chávez

    2011-12-01

    Full Text Available El presente estudio describe las características de la productividad pesquera por un periodo de cuatro años  en la “cocha Jacinto”. La “cocha Jacinto” está ubicada en la Reserva Nacional Pacaya Samiria (RNPS (coordenadas UTM E 0623314 y N 9495909, Loreto, Perú. Los datos fueron recolectados a partir de fichas de registro de pesca llenadas por el propio pescador. La productividad pesquera se estimó por el número de individuos con mayor captura, captura por unidad de esfuerzo (CPUE  y biomasa bruta según consumo (BBC. Los datos fueron digitados y analizados utilizando el programa Microsoft Excel v. 2000. Durante el periodo 2006 – 2009: a Los individuos con mayor captura fueron la “Carachama” (Fam. Loricaridae, “sardina” (Fam. Characidae, “Fasaco” (Fam. Erythrinidae y “Shuyo” (Fam. Erythrinidae; b con respecto a la CPUE: 0.16 kg/hora,  0.15 kg/hora, 0.38 kg/hora y 0.65 kg/hora; y c la BBC osciló entre 56.85 kg, 45.81 kg, 202.04 kg y  81.63 kg, según respectivo año. Las diferencias de la CPUE indican un probable incremento de la producción pesquera. Sin embargo se necesitan mayores estudios para evaluar las dinámicas de la producción pesquera y evaluar factores sociales.  Limitación a considerar es la calidad de los datos recolectados.

  16. Characterization of nitrides in an AISI 1010 steel; Caracterizacion de nitruros en un acero AISI 1010

    Energy Technology Data Exchange (ETDEWEB)

    Naquid G, C. [Instituto Nacional de Investigaciones Nucleares, Gerencia de Ciencia de Materiales, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1998-07-01

    It was characterized the phase formation in the 1010 carbon steel nitrided in a plasma reactor nearby to eutectoid point. The microstructure and identification of these ones were evaluated by Optical microscopy (OM), Dilatometry and X-ray diffraction (XRD). (Author)

  17. ENZIMAS LIPOLITICAS DE KRILL ANTARTICO: PURIFICACION Y CARACTERIZACION, ENZIMAS ADAPTADAS AL FRIO?.

    OpenAIRE

    BARRIGA GONZALEZ, ANDRES ANTONIO; BARRIGA GONZALEZ, ANDRES ANTONIO

    2006-01-01

    La temperatura es uno de los factores ambientales más importantes para la vida, siendo los ambientes fríos los que presentan la mayor distribución en la biosfera. Diferentes organismos han desarrollado diversas estrategias de tolerancia y adaptación al fr 160p.

  18. Characterization of radioactive organic liquid wastes; Caracterizacion de desechos liquidos organicos radiactivos

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez A, I.; Monroy G, F.; Quintero P, E.; Lopez A, E.; Duarte A, C., E-mail: ivonne-arce@hotmail.com [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    With the purpose of defining the treatment and more appropriate conditioning of radioactive organic liquid wastes, generated in medical establishments and research centers of the country (Mexico) and stored in drums of 208 L is necessary to characterize them. This work presents the physical-chemistry and radiological characterization of these wastes. The samples of 36 drums are presented, whose registrations report the presence of H-3, C-14 and S-35. The following physiochemical parameters of each sample were evaluated: ph, conductivity, density and viscosity; and analyzed by means of gamma spectrometry and liquid scintillation, in order to determine those contained radionuclides in the same wastes and their activities. Our results show the presence of H-3 (61%), C-14 (13%) and Na-22 (11%) and in some drums low concentrations of Co-60 (5.5%). In the case of the registered drums with S-35 (8.3%) does not exist presence of radioactive material, so they can be liberated without restriction as conventional chemical wastes. The present activities in these wastes vary among 5.6 and 2312.6 B g/g, their ph between 2 and 13, the conductivities between 0.005 and 15 m S, the densities among 1.05 and 1.14, and the viscosities between 1.1 and 39 MPa. (Author)

  19. CARACTERIZACION FISICOQUIMICA DEL MANGO COMUN (Mangifera indica L. DURANTE SU PROCESO DE MADURACION

    Directory of Open Access Journals (Sweden)

    VICTOR QUINTERO C

    Full Text Available El proceso de maduración del mango está gobernado bajo una serie de reacciones bioquímicas al interior del fruto que se caracterizan por cambios en la textura, color, en el contenido de azúcares, ácidos, aromas, entre otros. Las sustancias acumuladas durante el desarrollo se transforman de manera lenta y progresiva hasta que el fruto alcanza las condiciones de aroma y jugosidad que permita clasificarlo como maduro. Se realizó una cinética de maduración durante nueve días, determinando parámetros físicos y químicos como color en pulpa y en cáscara, textura, actividad de agua, sólidos solubles, pH y acidez titulable. Se modeló cinéticamente el comportamiento de cada una estas variables y se pudo determinar que los sólidos solubles tienen una tendencia explicada con un modelo de regresión multiplicativo y la actividad de agua con un modelo de regresión reciproco de X mientras el pH y la acidez con una ecuación de regresión de raíz cuadrada de X, de la misma manera el cambio de color en cáscara y en pulpa presento una regresión reciproca de X. Por último en el caso de la textura se observó y se ajustó modelos lineales tanto para cáscara como para pulpa.

  20. Medida y caracterizacion de la pobreza en la Region de Murcia.

    Directory of Open Access Journals (Sweden)

    Lafuente Lechuga, Matilde

    2008-01-01

    Full Text Available Esta comunicación pretende servir de acercamiento al fenómeno de la exclusión social, mediante la evaluación de la pobreza en la Región de Murcia y su alcance en relación con el conjunto nacional. Se aborda la medición y caracterización de la pobreza monetaria, haciendo referencia a su sentido más restringido, o en términos de escasez de renta. Para este estudio se utiliza la Encuesta de Condiciones de Vida (ECV relativa al año 2004.

  1. Tecnicas avanzadas de medida en intensimetria acustica para la caracterizacion de materiales aislantes

    Science.gov (United States)

    Munuera Saura, Gregorio

    The measurement rate of acoustic reduction (R) in an insulating material is determined in special designed enclosures according to UNE EN ISO 140-1 standard. The construction of a testing room that complies with the standards requires a significant financial investment, that too often can not be provided by general machinery manufacturers. The outdoor machines have to be designed considering the noise emission limits established in the European Directive 2000/14, making the installment of insulating materials in enclosures of machines necessary. Suppliers of insulating materials for industrial use does not normally provide the insulating properties of their products, which are often obtained from rock wool, polyethylene, polyurethane, synthetic rubber, etc. It is difficult to test these materials that are characterized by low density surface in a room standardized test procedure that is based on the measurement of sound pressure. The main problem is getting the validation of the measurement when the rate of acoustic reduction is relatively low, as in the case of materials mentioned above. An alternative procedure is proposed in this Doctoral Thesis based on the measurement of sound intensity. The vector nature of this parameter allows just the flow of energy through a given surface to be measured. The validation of the measurement is achieved with the highest degree of accuracy by applying the criteria included in the standard UNE EN ISO 9614. A steel plate 6 mm thick incorporated with a sound source for amplification of a pink noise signal is designed for carrying out the tests. Faced with the source is placed a piece of material to test. The source is connected and the transmitted sound intensity is measured with a probe consisting of two microphones located opposite one another. Previously it has been determined the flow of acoustic energy that impinges on the piece. The difference between the two measures provides directly the rate of acoustic reduction. The main advantage of the described test procedure is that it can be done in a room with normal dimensions and without specific conditioning. The vibroacoustic behaviour of the testing box and its influence on the measures is another important aspect to be considered. A test of modal analysis has been carried out with a steel plate similar to the enclosures of the box. A mathematical model based on the Statistical Energy Analysis SEA has been developed to estimate the paths of energy transmission from the sound source to the point of measurement with the sound intensity probe. The commercial software AUTOSEA2 LT is used. General conclusions regarding the alternative method of measurement and specific ones related to the capacity of insulation of the tested materials have been obtained. As for the general conclusions, the limitations of measuring with the intensity probe at low and high frequencies have been proved, validating measurements with an accuracy of 0.5 dB according to the criteria set forth in the standard UNE EN ISO 9614 Part 3 have been obtained, and a new test procedure for easy determination of the rate of acoustic reduction of an insulating material with low density surface has been established. Finally, the devised procedure allows future developments in the field of vibroacoustics, such as the application of the principle of reciprocity and the determination of acoustic impedance of materials by application of techniques for measuring of acoustics intensity.

  2. Caracterizacion de materiales magnetoelasticos y su aplicacion al control de vibraciones

    Science.gov (United States)

    Morales Robredo, Angel Luis

    The characterization and application of magnetoelastic materials to problems of vibration control is tackled in this thesis. Although this subject has been thoroughly studied since the nineteenth century, and despite the fact that this type of material is currently of topical interest due to their use as smart materials in several fields of science and engineering, there is room for further research in this field, specially in topics concerning measurement and application of DeltaE- and DeltaΨ- effects. Throughout this work, several contributions can be found. First, a new experimental system for measuring both DeltaE- and DeltaΨ- effects, simultaneously, has been developed with new or improved features. Second, this new experimental system has been used to characterize in depth the three classical ferromagnetic materials, nickel, cobalt and iron, and also Terfenol-D, a special alloy which shows a great magnetoelastic response. Third, the influence of internal stresses on both DeltaE- and DeltaΨ- effects has been studied by means of different heat treatments applied to nickel specimens. And fourth, the more suitable materials regarding their DeltaE- and DeltaΨ- effects were selected and applied to novel ways of vibration control. The results obtained in the different parts of this thesis are, in our humble opinion, very valuable. Regarding the new experimental system, the improvements endow the method with notable advantages over other techniques, such as lack of mechanical or magnetic interaction with the specimen, high accuracy and resolution in magnetic field, speed of measurement, no need for sample preparation, possibility of studying stress dependence, full automation and integration of the measurement and post-processing stages. Regarding the measurement of DeltaE- and DeltaΨ- effects, our results agree with the literature but provide better accuracy. Terfenol-D shows the highest DeltaE-effect (95%), followed at a great distance by nickel (3.75%), cobalt (0.60%) and iron (0.22%), whereas the DeltaΨ-effect is high in all cases (40% in most cases, 80% in nickel). Regarding the influence of internal stress, it is stated that annealing treatments leading to lower internal stresses maximize the magnetoelastic behaviour of the material, as in the instance of nickel were the DeltaE- and DeltaΨ- effects were maximized from 3.75% to 13.00% and from 80% to 99.99%, respectively. Finally, regarding the vibration control problem, two different strategies were tested: passive control and adaptative-passive control. Both methods showed excellent results in terms of reduction of the establishing time in free vibration (63% with annealed nickel) and in terms of reduction of the magnification factor in forced vibration (34% with annealed nickel and 64% with Terfenol-D).

  3. Modelizacion, simulacion y caracterizacion acustica de materiales para su uso en acustica arquitectonica

    Science.gov (United States)

    Julia Sanchis, Ernesto

    The global objective of this thesis consists on evaluating the viability of applying new sound absorbent materials that attempt, on one hand, to be an alternative to those materials classically used (as mineral wools) and, on the other hand, to offer a solution to one of the most important problems: the use of waste products of the textile industries by means of the recycled. For carrying out this study, some of the parameters that allow to characterize the acoustic behaviour of sound absorbent materials (such as the acoustic impedance, the acoustic absorption coefficient and the flow resistivity, among other) have been studied. Different experimental methods used to obtain these acoustic parameters have also been described. Among the methods presented in this work, the attention has been focused in those based on the acoustic impedance tube (Kundt tube). This technique presents advantages, for example, that only a small space in the laboratory is required as well as the samples of the testing materials are of small dimensions. The study has settled on three fundamental pillars: mathematical modelization, acoustic characterization of materials and numerical simulation. In the first place, after reviewing the main models and theories used in the acoustic evaluation of the porous and fibrous sound absorbent materials, a new mathematical model has been proposed and its validity is demonstrated for the type of studied materials. With regard to the acoustic characterization, diverse campaigns of measurements have been carried out with the purpose of obtaining the acoustic absorption coefficient and the flow resistivity of different type of materials. Finally, by means of a computer program based on the finite element method, the technique of the numerical simulation has been applied with the purpose of contrasting the obtained results experimentally, as well as for the evaluation of one of the most significant industrial applications from the acoustic point of view: the acoustic filters, that are devices designed to reduce the acoustic emission in a tube (as the expansion chambers in the exhaust pipes of the combustion engines). In a first phase of the study, it is observed that the obtained results agree with the experience and, in a second phase, a parametric study to evaluate the efficiency of this type of components is carried out. The numerical simulation presents the advantage of carrying out these studies without necessity of building the real models, with the saving in cost and time that this supposes. In this work, it has been sought to contribute to the knowledge of the acoustic behaviour of different type of materials and devices that are used to improve the acoustic isolation and acoustic conditioning.

  4. CARACTERIZACION MORFOMETRICA DE LA GERMINACION DE CHLORAEA CRISPA LINDL. (ORCHIDACEAE) USANDO UN ANALISIS DE IMAGEN

    OpenAIRE

    Verdugo, Gabriela; Marchant, Jorge; Cisternas, Mauricio; Calderón, Ximena; Peñaloza, Patricia

    2007-01-01

    Mediante la técnica de análisis de imagen se evaluó las etapas de germinación de un lote de semillas de Chloraea crispa Lindl. Se pudo observar las cuatro etapas de germinación propuestas por Mitchell. La etapa cero corresponde a semillas sin germinar, éstas son alargadas, curvadas en uno de sus extremos, y alcanzan un largo promedio de 0,5 mm. En la etapa uno se aprecia un incremento sólo en ancho debido al crecimiento del embrión, en la etapa dos hay cambios tanto en la forma como en el aum...

  5. Characterization of nano structured metallic materials; Caracterizacion de materiales metalicos nanoestructurados

    Energy Technology Data Exchange (ETDEWEB)

    Marin A, M.; Gutierrez W, C.; Cruz C, R.; Angeles C, C. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    1997-07-01

    Nowadays the search of new materials with specific optical properties has carried out to realize a series of experiments through the polymer synthesis [(C{sub 3}N{sub 3}){sub 2} (NH){sub 3}]{sub n} doped with gold metallic nanoparticles. The thermal stability of a polymer is due to the presence of tyazine rings contained in the structure. The samples were characterized by High Resolution Transmission Electron Microscopy, X-ray diffraction by the Powder method, Ft-infrared and its thermal properties by Differential Scanning Calorimetry (DSC) and Thermogravimetry (TGA). One of the purposes of this work is to obtain nano structured materials over a polymeric matrix. (Author)

  6. Volumetric and superficial characterization of carbon activated; Caracterizacion volumetrica y superficial de carbon activado

    Energy Technology Data Exchange (ETDEWEB)

    Carrera G, L.M.; Garcia S, I.; Jimenez B, J.; Solache R, M.; Lopez M, B.; Bulbulian G, S.; Olguin G, M.T. [Departamento de Quimica, Gerencia de Ciencias Basicas, Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    The activated carbon is the resultant material of the calcination process of natural carbonated materials as coconut shells or olive little bones. It is an excellent adsorbent of diluted substances, so much in colloidal form, as in particles form. Those substances are attracted and retained by the carbon surface. In this work is make the volumetric and superficial characterization of activated carbon treated thermically (300 Centigrade) in function of the grain size average. (Author)

  7. METODOLOGIA DE CARACTERIZACION CONCEPTUAL POR CONDICIONAMIENTOS SUCESIVOS. UNA APLICACION A SISTEMAS MEDIOAMBIENTALES.

    OpenAIRE

    PEREZ BONILLA, ALEJANDRA

    2009-01-01

    En clasificación automática se buscan perfiles subyacentes a la estructura de un dominio que ayude a comprenderlo y permita una mejor toma de decisiones. Por ello comprender el significado de las clases resulta fundamental. Por otro lado la validación de un cluster sigue siendo un problema abie~to por no haberse encontrado aún un criterio objetivo para determinar la calidad de un conjunto de clases en el contexto del clusteríng (Hand 1996), que se aplica en situaciones en las que no hay un bu...

  8. Caracterizacion dosimetrica del equipo de Terapia Superficial Therapax del Hospital Mexico

    International Nuclear Information System (INIS)

    Bernui De Vivanco, Maria Giselle; Rojas Rivas, Jorge; Cardenas Retuerto, Augusto

    2007-01-01

    The Servicio de Radioterapia of the Hospital Mexico in San Jose, Costa Rica has a Superficial Therapy equipment Therapax model DXT 300. It describes the measurements for the dosimetric characterization of the configurations 100 kVp, 25 mA and filter of 2.4 mm of Al, and 250 kVp, 10 mA and filter of 2.5 mm of Cu, taking into account that the uncertainties in the measurements of the superficial therapy equipment are higher than in the rank of the megavoltage [es

  9. Caracterizacion y optimizacion electroquimica de dispositivos electrocromicos duales basados en polimeros conductores

    Science.gov (United States)

    Padilla Martinez, Javier

    The aim of this thesis is to emphasize the existing relations between electrochemical processes, or electrochemical magnitudes, and colour changes. The work is focused on two aspects: individual spectroelectrochemical characterization of the constituent materials followed by an electrochemical and optical study of the performance of the dual system constructed with those materials. The objective is the optimization of both electrochemical and optical processes in dual conducting polymer systems, obtaining experimental methodologies able to characterize, predict, and finally design optimal dual electrochromic devices. The first part of the study is focused on the development of the proper methodology to obtain an optical characterization of any electrochromic material as a function of its electrochemical properties. Materials used were poly((3,4-ethylenedioxy)thiophene) (PEDOT) and poly-(3,6-bis(2-(3,4-ethylenedioxy)thienyl)-N-methylcarbazole) (PBEDOT-NMCz). PEDOT films are coloured under reduction, while PBEDOT-NMCz are coloured under oxidation, showing complementary colouration, and so they can be used to construct a dual electrochromic device. Based on the obtained experimental results, a theoretical study was undertaken to establish the optical responses of a system comprising several electrochromic layers. The theoretically obtained relations were experimentally proved. Relations obtained allow the prediction of the maximum contrast configuration for a dual system, as a function of the individual electrochemical properties of each constituent material. The system studied was PEDOT/PBEDOT-NMCz. The third chapter deals with the proposal and development of a new experimental methodology able to register the individual oxidation states of each electrode during operation of a dual device, obtaining then direct information about device performance. This methodology allows the study of the influence of different physical and chemical variables, like ratio of redox charge between both constituent films, applied potential to the device and initial oxidation state of the constituent polymer films, on the device performance. The final objective of this work is the construction of electrochromic devices that can be use in real applications out of research or academic contexts. It is necessary then, for safety purposes, to use solid electrolytes in the cell. For final applications it is also required to construct devices of appropriate dimensions. In the fourth chapter, the construction and study of large dimensions and solid state devices for the system PEDOT/PBEDOT-NMCz was carried out. The information obtained in previous sections was used to determine maximum contrast combinations. Problems related to electrodeposition of conducting polymers on large surfaces (around 30 cm2) are discussed, together with the optimization of switching speeds when a solid electrolyte is used. Finally the ability to tune colour states and retain them in the absence of an external potential applied was studied and discussed. The last section deals with the study of two new cathodically colouring polymers, poly(3-(Biphenyl-4-ylmethoxymethyl)-3,4-dihydro-2H-thieno(3,4-b)-(1,2)dioxepine) (BPMOM-ProDOT) and poly-dibenzylProDOT (PDiBz-ProDOT), which have been reported to show larger contrasts than PEDOT. For this reason, dual cells were constructed and checked by combination of these two polymers with PBEDOT-NMCz. The methodology previously developed and used to characterize PEDOT and PBEDOT-NMCz was applied to these polymers. The developed theoretical equations were used to determine the maximum contrast for both systems. Finally, the use of standard optical magnitudes as photopic values is emphasized. Photopic values are standardized by the Commission Internationale de l'Eclairage (CIE), and correspond to real sensations perceived by the human eye, whose sensitivity is different for each wavelength. In this sense the use of photopic values, instead of values corresponding to a single wavelength, is encouraged. (Abstract shortened by UMI.)

  10. Importance of the planning activities, cutting, handling and analysis of the nuclei of oil well drilling; Importancia de las actividades de planificacion, corte, manejo y analisis de los nucleos de perforacion de pozos petroleros

    Energy Technology Data Exchange (ETDEWEB)

    Contreras L, Enrique A; Garcia M, Pablo [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2007-07-01

    , recipientes de almacenamiento de hidrocarburos, agua y energia calorifica, asi como barreras impermeables y medios de transporte de la energia y de los fluidos. Entre las propiedades mas importantes que se utilizan para describir estas funciones se encuentran la porosidad, la permeabilidad, la compresibilidad del volumen de poros, el factor de resistividad de la formacion, el exponente de saturacion, la velocidad de las ondas acusticas P y S, las permeabilidades relativas, las presiones capilares, las constantes elasticas y otras propiedades mecanicas, el coeficiente de dilatacion termica, la conductividad termica, la difusividad termica y el calor especifico. La ejecucion de una amplia variedad de actividades relacionadas con las etapas de exploracion, localizacion, evaluacion y desarrollo de los yacimientos petroleros, depende fuertemente de que se tenga un buen conocimiento de la magnitud y de la variabilidad espacial de estas propiedades. Tanto la factibilidad tecnica como la economica de desarrollar un prospecto de yacimiento petrolero, dependen de que las rocas que intervienen exhiban una combinacion adecuada de sus propiedades, para asi constituir una estructura geologica confinante y almacenadora de hidrocarburos, que sea factible de desarrollarse tecnicamente, a la vez que tenga el potencial de redituar un beneficio economico. En este contexto, desde la plataforma de experiencia que se tiene sobre el tema en el Laboratorio de Yacimientos del Instituto de Investigaciones Electricas. En el presente articulo se aborda la relevancia que tienen las actividades de corte, manejo y analisis de laboratorio de los nucleos de perforacion de pozos petroleros, para la evaluacion de las formaciones geologicas, en relacion con la caracterizacion, la evaluacion y el aprovechamiento de los yacimientos petroleros.

  11. Geologic and petrophysic analysis of a travertine block as hydrocarbon reservoir analogue; Analise geologica e petrofisica de um bloco de travertino como analogo de reservatorio de hidrocarbonetos

    Energy Technology Data Exchange (ETDEWEB)

    Basso, Mateus; Kuroda, Michelle Chaves; Vidal, Alexandre Campane, E-mail: mbstraik@gmail.com, E-mail: ckuroda@ige.unicamp.br, E-mail: vidal@ige.unicamp.br [Universidade Estadual de Campinas (CEPETRO/UNICAMP), SP (Brazil). Centro de Estudos do Petroleo

    2017-04-15

    Microbialitic limestones are gaining space in petroleum geology due to the existence of many reservoirs composed of these lithologies in the pre-salt producing fields. Travertine, calcareous tufa and stromatolites figure among the rocks proposed as analogous for the microbialitic rocks. This work conduces the study of geological, petrophysical and geophysical parameters of a travertine block measuring 1,60 x 1,60 x 2,70 m, weighing 21,2 tons and available in the Centro de Estudo do Petroleo (CEPETRO) at the Universidade Estadual de Campinas. The Italian block, named T-block, corresponds to the representative elementary volume of its original formation and allows the study in an intermediate scale between the hand sample and the outcrop scale. Permeability tests and gamma ray spectrometry measurements were conducted and the porosity was calculated by image analysis. Models were generated from the obtained data and then associated with descriptive geology of the block. A reduction in permeability, porosity and concentration of elements potassium (K), uranium (U) and thorium (Th) was recorded, following a gradient towards the top of the T-block accompanying the reduction in the degree of development of the rock fabric. (author)

  12. Orbital forcing of the late Pleistocene boreal summer monsoon: Links to North Atlantic cold events and El Nino; Southern Oscillation. Geologica Ultraiectina (313)

    NARCIS (Netherlands)

    Ziegler, M.

    2009-01-01

    This thesis revolves about the timing of precession-related variations in the boreal summer monsoon and the impact of North Atlantic cold events and the El Nino Southern Oscillation on this timing. Transient climate modelling experiments indicate that the intensity of the Northern Hemisphere summer

  13. Statistical analysis of the potassium concentration obtained through; Analise estatistica da concentracao de potassio obtida por aerolevantamentos geofisicos em diferentes formacoes geologicas na regiao de Santa Maria, RS

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Joao Eduardo da Silva [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Dept. de Estatistica]. E-mail: jesp61@gmail.com; Silva, Jose Luiz Silverio da; Pires, Carlos Alberto da Fonseca [Universidade Federal de Santa Maria (UFSM), RS (Brazil). Lab. de Hidrogeologia; Strieder, Adelir Jose [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Lab. de Modelagem Geologica e Ambiental

    2007-07-01

    The present work was developed in outcrops of Santa Maria region, southern Brazil, Rio Grande do Sul State. Statistic evaluations were applied in different rock types. The possibility to distinguish different geologic units, sedimentary and volcanic (acid and basic types) by means of the statistic analyses from the use of airborne gamma-ray spectrometry integrating potash radiation emissions data with geological and geochemistry data is discussed. This Project was carried out at 1973 by Geological Survey of Brazil/Companhia de Pesquisas de Recursos Minerais. The Camaqua Project evaluated the behavior of potash concentrations generating XYZ Geosof 1997 format, one grid, thematic map and digital thematic map files from this total area. Using these data base, the integration of statistics analyses in sedimentary formations which belong to the Depressao Central do Rio Grande do Sul and/or to volcanic rocks from Planalto da Serra Geral at the border of Parana Basin was tested. Univariate statistics model was used: the media, the standard media error, and the trust limits were estimated. The Tukey's Test was used in order to compare mean values. The results allowed to create criteria to distinguish geological formations based on their potash content. The back-calibration technique was employed to transform K radiation to percentage. Inside this context it was possible to define characteristic values from radioactive potash emissions and their trust ranges in relation to geologic formations. The potash variable when evaluated in relation to geographic Universal Transverse Mercator coordinates system showed a spatial relation following one polynomial model of second order, with one determination coefficient. The statistica 7.1 software Generalist Linear Models produced by Statistics Department of Federal University of Santa Maria/Brazil was used. (author)

  14. Radioactivity of rocks from the geological formations belonging to the Tibagi River hydrographic basin; Radioatividade de rochas provenientes das formacoes geologicas pertencentes a bacia hidrografica do Rio Tibagi

    Energy Technology Data Exchange (ETDEWEB)

    Bastos, Rodrigo Oliveira

    2008-07-01

    This work is a study of the {sup 40}K and the {sup 238}U and {sup 232}Th series radioactivity in rocks measured with high resolution gamma ray spectrometry. The rocks were taken from the geologic formations in the region of the Tibagi river hydrographic basin. The course of this river cuts through the Paleozoic and Mesozoic stratigraphic sequences of the Parana sedimentary basin. In order to take into account the background radiation attenuation by the samples, a technique was developed that eliminated the need to measure a blank sample. The effects of the radiation's self-attenuation in the sample matrix were taken into account by using a gamma ray direct transmission method. The results for 87 rock samples, taken from 14 distinct formations, and their corresponding radioactivity variations are presented and discussed according to the possible geological processes from which they originated. Among the most discussed results are: an outcrop that profiles shale, limestone and rhythmite in the Irati Formation; a sandstone and siltstone sequence from the Rio do Rasto Formation; and a profile sampled in a coal mine located in the Rio Bonito Formation. The calculations of the rocks' contributions to the outdoor gamma radiation dose rate agree with the values presented by other authors for similar rocks. The highest dose values were obtained from felsic rocks (rhyolite of the Castro group, 129.8 {+-} 3.7 nGy.h{sup -1}, and Cunhaporanga granite, 167 {+-} 37 nGy.h{sup -1}). The other highest values correspond to the shale rocks from the Irati Formation (109 {+-} 16 nGy.h{sup -1}) and the siltic shale rocks from the Ponta Grossa Formation (107.9 {+-} 0.7 nGy.h{sup -1}). The most recent geological formations presented the lowest dose values (e.g. the Botucatu sandstone, 3.3 {+-} 0.6 nGy.h{sup -1}). The average value for sedimentary rocks from seven other formations is equal to 59 {+-} 26 nGy.h{sup -1}. The Rio Bonito Formation presented the highest dose value (334 {+-} 193 nGy.h{sup -1}) mainly due to the anomalous {sup 226}Ra concentration in the samples. The Ra{sub eq} parameter and the activity concentration index for environmental radioactivity monitoring were calculated for rocks used as building materials. Only one sample reached a Ra{sub eq} value higher than 370 Bq.kg{sup -1}. In relation to the activity concentration index ali results are lower than two, satisfying the most rigorous dose criterion (0.3 mSv.a{sup -1}) for materials with restricted use (e.g. tiles and coverings). When materials used in bulk amounts are considered (e.g. bricks, sand, gravel), the Castro group and the Cunhaporanga granite samples do not satisfy the less rigorous dose criterion (1 mSv.a{sup -1}). This indicates that there is a radiological protection concern when these materials are used as concrete gravel. This result warrants a more detailed analysis using dose assessments based in the scenarios where these rocks are typically used. (author)

  15. Risk and geological uncertainties in carbonate reservoirs in Santos Basin; Incertezas geologicas e risco em reservatorios carbonaticos na Bacia de Santos

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Makoto; Cortez, Marcella M.M. [Queiroz Galvao Perfuracoes S.A., Rio de Janeiro, RJ (Brazil); Mendes, Marcos Huber

    2004-07-01

    The Lower Albian in the south part of Santos Basin is composed mainly of oolitic calcarenites and calcilutites organized in shoaling upward cycles. The calcarenites from the top of the sequence constitute a package of reservoir zones and sub-zones with regional distribution along which are located mature, producing and development phase oil fields. In this work the main factors with major impact in reserves estimation are interpreted and quantified in a probabilistic approach giving support for the development plan phase of a field of the carbonatic trend. The regional stratigraphic and structural interpretations provided information about extension, external geometry, and continuity of the reservoir zones for reserves risk computation. The porosity probability density functions were defined according to stratigraphic position, seismic reflection pattern of calcarenites and also information from the discovery and the appraisal wells. The Decision Tree methodology with Monte Carlo Simulation was used to better understand the impact of geological uncertainties in reserves computation and also as a first step for risk management. The Monte Carlo simulation allows the Multivariate Sensibility and Scenario Analysis, Probabilistic Technical and Economic Evaluation and Optimal Portfolio Stochastic Simulation. (author)

  16. Geologic mapping around Mahoma mining. San Jose mining company;Carta geologica de los alrededores de Mina Mahoma, Compania Minera San Jose

    Energy Technology Data Exchange (ETDEWEB)

    Techera, J; Arrighetii, R

    1993-07-01

    This study has as main objective carry out a geological mapping as well as the structural analysis , in 1.5.000 scale in the zone where the gold benefit plant of San Jose mining company is settled (Mahoma Mining). From this study has been marked many drillings.

  17. Bayesian inversion of surface wave data for discontinuities and velocity structure in the upper mantle using Neural Networks. Geologica Ultraiectina (287)

    NARCIS (Netherlands)

    Meier, U.

    2008-01-01

    We present a neural network approach to invert surface wave data for discontinuities and velocity structure in the upper mantle. We show how such a neural network can be trained on a set of random samples to give a continuous approximation to the inverse relation in a compact and computationally

  18. Perseverance of pikas in the Miocene : Interplay of climate and competition in the evolution of Spanish Ochotonidae (Lagomorpha, Mammalia). Geologica Ultraiectina (333)

    NARCIS (Netherlands)

    Hordijk, K.

    2010-01-01

    The sedimentary succession near the village of Villafeliche in the Calatayud-Montalbán Basin (Spain) is well known for its very rich, densely sampled and well dated fossil mammal record of Miocene age and roughly spans the time interval between 17 and 10 million years ago. The exceptional quality of

  19. Subsurface impact of CO2: Response of carbonate rocks and wellbore cement to supercritical CO2 injection and long-term storage. Geologica Ultraiectina (310)

    NARCIS (Netherlands)

    Liteanu, E.

    2009-01-01

    Capture of CO2 at fossil fuel power station coupled with geological storage in empty oil and gas reservoirs is widely viewed as the most promising option for reducing CO2 emissions to the atmosphere, i.e. for climate change mitigation. Injection of CO2 into such reservoirs will change their chemical

  20. Sulfur isotopes as a tracer for biogenic sulfate reduction in natural environments: A link between modern and ancient ecosystems. Geologica Ultraiectina (316)

    NARCIS (Netherlands)

    Stam, M.C.

    2010-01-01

    Sulfur isotopes have been widely used to trace the activity of sulfate reducing prokaryotes in modern and ancient geochemical settings and to estimate the role of this microbial metabolism in global sulfur cycling. Extensive pure culture data provide detailed insight into cellular mechanisms

  1. Seismic, gravimetric and geological interpretation of an Andean transect in Venezuela; Interpretacion sismica, gravimetrica y geologica de un perfil transandino venezolano

    Energy Technology Data Exchange (ETDEWEB)

    Jacome R, Maria Ines; Audemard, Felipe; Gratero, Victor [Universidad Simon Bolivar, Caracas (Venezuela)

    1995-12-31

    The combination of seismic, gravimetric and geologic data allowed the construction of a crustal model from the Venezuela Andes. This model is aiming to improve the knowledge from this problematic region. The profile is 160 Km long and it cuts perpendicularly the Andes, across the Soledad, Celoso, Bocono, Virtudes and Gavilan faults. The interpreted reflexions seismic profiles lie both flanks of the Venezuelan Andes. Bouguer anomaly lows do not occurs along the central axis but on the satellite basins located along the Northwestern and Southeastern flanks. The contours tend to group on these flanks reflecting a system related to reverse faults. It was also observed a density contrast separating the Cretaceous-Tertiary from the basement lying at depths greater than 5 Km in the northern Barinas Basin. The same contrast was detected around 10 km along the southern Lake Maracaibo area. The Venezuelan Andes is an asymmetric northern vergent Neogene structure generated under compression, transmitted along basement involved thrusts dipping Southeast. In consequence the tectonic transport is from the Southeast to the Northwest. (author). 7 refs., 5 figs., 2 tabs

  2. "Carta geologica totius Poloniae, Moldaviae, Transilvaniae et partis Hungariae et Valachiae" by S. Staszic and its importance for European geology and geological cartography

    Czech Academy of Sciences Publication Activity Database

    Czarniecki, S.; Grigelis, A.; Kozák, Jan; Narebski, W.; Wójcik, Z.

    -, č. 6 (2008), s. 81-101 ISSN 1507-0557 Institutional research plan: CEZ:AV0Z30120515 Keywords : history of geology * geological cartography * Stanislaw Wawrzyniec Staszic Subject RIV: DB - Geology ; Mineralogy

  3. Land Use, Biofuels and Rural Development in the La Plata Basin ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Yet the environmental, social and economic impacts on the basin remain largely unknown and ... Argentina, South America, Bolivia, Brazil, Paraguay, Uruguay, North and Central America ... IDRC at the ICLEI Resilient Cities 2018 conference.

  4. Espacialidad y trabajo: los cartoneros en la ciudad de La Plata

    Directory of Open Access Journals (Sweden)

    María Eugenia Rausky

    2016-04-01

    Full Text Available En el trabajo que aquí presentamos se aborda la forma que asume el vínculo espacio-trabajo para quienes viven de la recolección de basura, cartón, papel y afines, es decir, los cartoneros –niños y adultos-. Nos preguntamos por el modo en que una actividad que se desarrolla en el espacio público, es vivida por los sujetos que la practican: ¿Qué particularidades asume el trabajo que se lleva a cabo en las calles? ¿Cómo es vivida, sentida y practicada la ciudad por los trabajadores que despliegan sus actividades laborales en la vía pública? ¿Qué tipo de sociabilidad se desarrolla en el espacio de trabajo? ¿Qué vínculos tejen con el centro de la ciudad aquellos habitantes que viven en los márgenes? Nos interesa caracterizar los modos que tienen de practicar y representar el espacio laboral, analizando las repercusiones de ello en los sentidos que los sujetos le asignan a su trabajo. La estrategia de investigación empleada es cualitativa y está basada en entrevistas en profundidad y observación participante.

  5. Effective mitigation of debris flows at Lemon Dam, La Plata County, Colorado

    Science.gov (United States)

    deWolfe, V.G.; Santi, P.M.; Ey, J.; Gartner, J.E.

    2008-01-01

    To reduce the hazards from debris flows in drainage basins burned by wildfire, erosion control measures such as construction of check dams, installation of log erosion barriers (LEBs), and spreading of straw mulch and seed are common practice. After the 2002 Missionary Ridge Fire in southwest Colorado, these measures were implemented at Knight Canyon above Lemon Dam to protect the intake structures of the dam from being filled with sediment. Hillslope erosion protection measures included LEBs at concentrations of 220-620/ha (200-600% of typical densities), straw mulch was hand spread at concentrations up to 5.6??metric tons/hectare (125% of typical densities), and seeds were hand spread at 67-84??kg/ha (150% of typical values). The mulch was carefully crimped into the soil to keep it in place. In addition, 13 check dams and 3 debris racks were installed in the main drainage channel of the basin. The technical literature shows that each mitigation method working alone, or improperly constructed or applied, was inconsistent in its ability to reduce erosion and sedimentation. At Lemon Dam, however, these methods were effective in virtually eliminating sedimentation into the reservoir, which can be attributed to a number of factors: the density of application of each mitigation method, the enhancement of methods working in concert, the quality of installation, and rehabilitation of mitigation features to extend their useful life. The check dams effectively trapped the sediment mobilized during rainstorms, and only a few cubic meters of debris traveled downchannel, where it was intercepted by debris racks. Using a debris volume-prediction model developed for use in burned basins in the Western U.S., recorded rainfall events following the Missionary Ridge Fire should have produced a debris flow of approximately 10,000??m3 at Knight Canyon. The mitigation measures, therefore, reduced the debris volume by several orders of magnitude. For comparison, rainstorm-induced debris flows occurred in two adjacent canyons at volumes within the range predicted by the model. ?? 2007 Elsevier B.V. All rights reserved.

  6. Las desventuras de Nora en el Río de la Plata

    Directory of Open Access Journals (Sweden)

    Tania Diz

    2012-04-01

    Full Text Available En este artículo se analizan dos obras teatrales: Dos mujeres- El amo del mundo (1927, de Alfonsina Storni, y Las descentradas (1929, de Salvadora Medina Onrubia. En sendas obras, las autoras oponen las formas de la subjetividad femenina hegemónica y contra hegemónica, hipotetizando sobre las causas y consecuencias que afectan a los personajes femeninos transgresores. Desde este punto de partida, se indaga acerca de los procedimientos que ponen en evidencia una lógica feminista, capaz de transgredir los estereotipos sexuados del falogocentrismo.

  7. CONFLICTO Y VIOLENCIA FAMILIAR EN EL RIO DE LA PLATA 1770-1810

    Directory of Open Access Journals (Sweden)

    JOSÉ LUIS MORENO

    2011-10-01

    Full Text Available La estabilidad del imperio español en América no sólo dependía de una economía organizada para sostener la metrópolis y sus dominios, sino también de una serie de condiciones políticas, sociales, religiosas y culturales, sin las cuales el orden imperial podía correr el riesgo de disgregarse en la extensión de su abigarrada geografía, y del no menos complejo caleidoscopio social, etnocultural y político. Uno de los pilares fundamentales del sistema imperial era la familia constituida a través del matrimonio religioso. El matrimonio en América, como ocurrió en Europa, fue el núcleo institucional fundamental y más estable, a pesar de las transformaciones sufridas en el tiempo, y base de la familia. Los conflictos y violencias familiares desafiaban constantemente la solidez de esa construcción social. De hecho, ciertos fenómenos comunes contribuyeron mucho más a esa disgregación social: las castas, es decir, los diferentes grupos étnicos, se mezclaban y constituían parejas dentro de las pautas religiosas y fuera de ellas, y para colmo sus demandas también llegaban a la autoridad o a la justicia. Si desde el punto de vista de la legitimidad social y política se impulsaba la relación matrimonial clásica o «connubio», en la realidad de los distintos estratos sociales se registraban situaciones de la clase de «contubernio»[1] (relaciones libres, concubinato.

  8. Natural resources economical activities in coastal area of Rio de la Plata: report

    International Nuclear Information System (INIS)

    Fernandez, V.; Garibotto, S.; Gorfinkiel, D.; Pena, C.; Resnichenko, Y.

    2011-01-01

    The integrated management of coastal zone covers multiple problems, often conflicts on the use of coastal resources that is different productive capacities, the presence of a variety of important actors a degree of relationship with the river and its surroundings, this is due to the pressures on coastal resources in a given area may be higher due to the activities that take place outside this area. Colonia, San Jose, Canelones and Maldonado are the departments of the Oriental Republic of Uruguay to which they have studied the impact on the national economy, economic characteristics of the population, business, mining, farming, tourism fores tal activities.

  9. Perfil de radiaciones electromagnéticas no ionizantes de la ciudad de La Plata

    OpenAIRE

    Vernieri, Julieta Z.; Rodríguez, Guillermo; Bava, José Alberto; Garavaglia, Mario J.

    2013-01-01

    El desarrollo tecnológico de los últimos años en el área de las comunicaciones ha incrementado el uso de ondas de radio de altas frecuencias en servicio que emplean WiFi o Bluetooth, teléfonos inalámbricos y celulares, por sólo citar algunas de las posibles fuentes. En consecuencia, vivimos inmersos en un nuevo tipo de polución intangible e inmaterial, denominada “contaminación electromagnética”. Esto ha producido una creciente preocupación en la población, en los ámbitos académicos y los ...

  10. Skate, espacios urbanos y jóvenes en la ciudad de La Plata

    OpenAIRE

    Saraví, Jorge Ricardo

    2012-01-01

    El objetivo general que nos hemos planteado fue analizar la práctica del skate que llevan adelante los y las jóvenes en la ciudad. Por otro lado, nuestros objetivos específicos fueron: 1) relevar y describir acciones, características, particularidades, lugares, que asumen las diferentes prácticas del skate en la ciudad; 2) conocer las representaciones que acerca de esa práctica tienen los propios jóvenes y la sociedad; 3) profundizar en las implicancias sociales que tiene una práctica corpora...

  11. ICON - Puerto Plata 2015 Meteorological and Oceanographic Observations (NCEI Accession 0156578)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Atlantic Oceanographic and Meteorological Laboratory (AOML) of OAR is conducting research on the influence of meteorological and oceanographic factors upon coral...

  12. Roasting of refractory gold and silver concentrate; Tostacion de un concentrado refractario de oro y plata

    Energy Technology Data Exchange (ETDEWEB)

    Coraonado, J. H.; Encinas, M. A.; Leyva, M. A.; Valenzuela, J. L.; Valenzuela, A.; Munive, G. T.

    2012-11-01

    In processing of precious metal ores with high pyrite content, refractory concentrates are obtained, which are difficult to process. A refractory gold and silver concentrate was leached with sodium cyanide. Results show low extraction percentages, being 34 % of gold and 40 % of silver. A roasting method to oxidize the concentrate was used, making it more susceptible to cyanidation, hence a more efficient way to extract precious metals. The variables include roasting temperature and roasting and cyanidation time. In addition, the hot calcine was added to the leaching solution at room temperature to analyze the effect on particle size and recovery. The best results, although not entirely satisfactory (50 % of gold and 61 % of silver) were obtained by roasting the concentrate for 4 h at 600 degree centigrade, followed by cyanidation for 20 h. The lime consumption to raise the pH to about 11.3 was increased markedly to 25 kg/m{sup 3}. (Author) 11 refs.

  13. La banda del Pata: sociabilidad y membrecías en la UOCRA La Plata

    OpenAIRE

    Farace, Rafael

    2016-01-01

    El presente trabajo pretende realizar una recuperación del enfoque etnográfico con el objetivo de reflexionar sobre sus aportes para el estudio de las organizaciones y las prácticas sindicales. Desde esta perspectiva, la reconstrucción dinámica de las relaciones cotidianas establecidas por los miembros de la UOCRA puede constituir una alternativa a las investigaciones que también desde un enfoque crítico enfatizaron la “reproducción” o la “resistencia” de las organizaciones de los trabajadore...

  14. Los Pinos River and Fountain Creek Hydraulic Evaluation and Floodplain Mapping, La Plata County, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Recent developments in digital terrain and geospatial database management technology make it possible to protect this investment for existing and future projects to...

  15. Junction Creek Hydraulic Evaluation and Floodplain Mapping, La Plata County, USA

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — Recent developments in digital terrain and geospatial database management technology make it possible to protect this investment for existing and future projects to...

  16. Silver precipitation from electrolytic effluents; Precipitacion de plata de efluentes electroliticos

    Energy Technology Data Exchange (ETDEWEB)

    Rivera, I.; Patino, F.; Cruells, M.; Roca, A.; Vinals, J.

    2004-07-01

    The recovery of silver contained in electrolytic effluents is attractive due to its high economic value. These effluents are considered toxic wastes and it is not possible to dump them directly without any detoxification process. One of the most important way for silver recovery is the precipitation with sodium ditionite, sodium borohidride or hydrazine monohidrate. In this work, the most significant aspects related to the use of these reagents is presented. Results of silver precipitation with sodium ditionite from effluents containing thiosulfate without previous elimination of other species are also presented. silver concentration in the final effluents w <1 ppm. (Author) 15 refs.

  17. La santé du rio de la Plata | CRDI - Centre de recherches pour le ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    15 juil. 2011 ... Parmi les partenaires, nous comptions la Faculté des sciences de la Universidad de la República de l'Uruguay, le Servicio de Oceanografia, Hidrografia y Meteorología de la Armada (SOHMA), el Instituto Nacional de Pesca (INAPE) et REDES — Amigos de la Tierra, une organisation non gouvernementale ...

  18. Esculturas de Hipócrates, Galeno y Manuel Plata Azuero

    Directory of Open Access Journals (Sweden)

    Alberto Albornoz Plata

    1996-08-01

    Full Text Available

    Dos agradables y emotivas sorpresas hemos experimentado en la tarde de hoy:

    Bellas obras de arte son las esculturas de Hipócrates y Galeno, que parecen saludar a todos los visitantes de la Academia al penetrar al salón principal. Por eso he querido recordar brevemente lo que estos personajes representan en la historia de la Medicina mundial y nacional.

    I. Hipócrates.

    Hipócrates.Nació en la isla griega de Cos, en el mar Egeo, en el año 4,60 A.c. Estudió medicina en Selymbria y sus maestros fueron Gorgias de Leontini y Demócrates. Muere en Tesalia a los 85 años. Fue muy distinguido por Platón y Aristóteles y es considerado universalmente como el Padre de la Medicina.

    Laennec, el famoso clínico francés del siglo XIX, lo consideró como genial por haber descrito tanto la sucusión torácica como la facies de los moribundos: ambas, en su honor, llevan el calificativo de “hipocráticas”. Hipócrates sostenía que la misma naturaleza cura las enfermedades. El “Corpus Hipocraticum”, que llegó hasta el Renacimiento por vía de los romanos y de los árabes, compendia el conocimiento médico de toda la antigüedad.

    El Juramento Hipocrático es su gran legado para los médicos: todos nosotros hemos prometido cumplirlo fielmente...

  19. Oraciones en plata: estudio de la obra inédita de Jacobo Pecul Montenegro

    Directory of Open Access Journals (Sweden)

    Canedo Barreiro, María

    2015-12-01

    Full Text Available The purpose of this research is the study and attribution of new pieces to Jacobo Pecul Monte negro (1753-1817 a silversmith from Santiago de Compostela. His production reflects an aesthetic clearly influenced by French forms which he learnt from his father Claudio Pecul. But also Galician artists´ work, such as Ferreiro or Simón Rodríguez, had an impact on Montenegro's own creations. Twenty four new pieces have been selected from parish crosses, holy chalices, ciboriums, censers, “navetas” and monstrances, which are referenced in Pecul's manuscript “Libro de Caja”. They were extracted by Couselo Bouzas in his Galicia Artística, and catalogued in the Diocesan Archive of the Catholic Church. These pieces have been studied and attributed to Jacobo Pecul Montenegro by the guidelines set by José Manuel López Vázquez, who has studied the work of this silversmith in depth. This article attempts to make a brief study of both the author and the silversmithing typologies in the shift from the baroque style to the neoclassical style. And at the same time this study also aims to draw attention to Galician silversmithing, which is a patrimony of our popular imagery, and more often than not highly neglected.La presente investigación tiene como objetivo el estudio y atribución de nuevas piezas al orfebre compostelano Jacobo Pecul Montenegro (1753-1817, cuya producción refleja una estética influida por una parte de las formas francesas aprendidas de su padre, Claudio Pecul, y por otra de los artistas gallegos, cómo Ferreiro o Simón Rodríguez. Se han seleccionado veinticuatro nuevas piezas entre cruces parroquiales, cálices, copones, incensarios, navetas y ostensorios, las cuales aparecen referenciadas en el Libro de Caja de Pecul, extractado por Couselo Bouzas en su Galicia Artística, y catalogadas en el Archivo Diocesano de la Iglesia Católica. Dichas obras han sido estudiadas y atribuidas a Jacobo Pecul siguiendo las directrices marcadas por José Manuel López Vázquez, quién ha tratado en profundidad la obra de este platero. En estas páginas se realiza un breve análisis del autor así como de las tipologías de orfebrería religiosa del cambio del barroco al neoclásico en Galicia, pretendiendo así mismo ser una llamada de atención sobre la platería gallega, un patrimonio que forma parte de nuestra imaginería popular y que a menudo queda en el olvido. [gl] A presente investigación ten como obxectivo o estudo e atribución de novas pezas ó orfebre compostelán Jacobo Pecul Montenegro (1753-1817, cuxa produción reflexa unha estética influída, por unha parte das formas francesas aprendidas de seu pai, Claudio Pecul, e pola outra dos artistas galegos, como Ferreiro ou Simón Rodríguez. Seleccionáronse vinte e catro novas pezas entre cruces parroquiais, cálices, copóns, incensarios, navetas e ostensorios, as cales aparecen referenciadas no Libro de Caixa de Pecul, extractado por Couselo Bouzas en Galicia Artística, e catalogadas no Arquivo Diocesano da Igrexa Católica. Ditas obras foron estudiadas e atribuídas a Jacobo Pecul seguindo as directrices marcadas por José Manuel López Vázquez, quen tratou en profundidade a obra deste prateiro. Nestas páxinas realizase unha breve análise do autor, así como das tipoloxías de ourivería relixiosa no cambio do barroco ó neoclásico en Galicia, pretendendo ó mesmo tempo ser unha chamada de atención sobre a pratería galega, un patrimonio que forma parte da nosa imaxinería popular e que a miúdo permanece esquecida.

  20. ¿Dónde está la plata para los empresarios colombianos?

    Directory of Open Access Journals (Sweden)

    Orlando Salinas Gómez

    2002-07-01

    Full Text Available Parte del espíritu emprendedor consiste en saber encontrar el dinero y saber cumplir con los requisitos que exigen las instituciones financieras. Se ofrece una relación de las principales fuentes de financiación a donde pueden recurrir nuestros emprendedores

  1. La santé du rio de la Plata | IDRC - International Development ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    15 juil. 2011 ... Parmi les partenaires, nous comptions la Faculté des sciences de la Universidad de la República de l'Uruguay, le Servicio de Oceanografia, Hidrografia y Meteorología de la Armada (SOHMA), el Instituto Nacional de Pesca (INAPE) et REDES — Amigos de la Tierra, une organisation non gouvernementale ...

  2. Servicios bibliotecarios accesibles para personas con discapacidad visual en la Universidad Nacional de La Plata, Argentina

    Directory of Open Access Journals (Sweden)

    María Cecilia Corda

    2014-01-01

    Full Text Available El trabajo, de tipo descriptivo exploratorio, pretende conocer cuál es el estado en que se encuentran algunas de las bibliotecas universitarias de la UNLP para ofrecer un servicio accesible a personas con discapacidad visual. Se anal iza qué servicios de este tipo poseen actualmente, con qué barreras se enfrentan los usuarios y qué soluciones se han implementado. A tal fin se indagará, por un lado, cómo están diseñados los sitios web de las bibliotecas elegidas, y por otro, cómo integr an estas bibliotecas en sus servicios y productos documentales a estas personas, esto es, si cuentan con material bibliográfico y servicios accesibles. Por último, se esbozan algunas propuestas para superar la situación actual en estas bibliotecas universi tarias.

  3. Servicios bibliotecarios accesibles para personas con discapacidad visual en la Universidad Nacional de La Plata, Argentina

    Directory of Open Access Journals (Sweden)

    María Cecilia Corda

    2014-01-01

    Full Text Available El trabajo, de tipo descriptivo exploratorio, pretende conocer cuál es el estado en que se encuentran algunas de las bibliotecas universitarias de la UNLP para ofrecer un servicio accesible a personas con discapacidad visual. Se analiza qué servicios de este tipo poseen actualmente, con qué barreras se enfrentan los usuarios y qué soluciones se han implementado. A tal fin se indagará, por un lado, cómo están diseñados los sitios web de las bibliotecas elegidas, y por otro, cómo integran estas bibliotecas en sus servicios y productos documentales a estas personas, esto es, si cuentan con material bibliográfico y servicios accesibles. Por último, se esbozan algunas propuestas para superar la situación actual en estas bibliotecas universitarias.

  4. ESI-PR16, Central La Plata, Puerto Rico 2000 (Environmental Sensitivity Index Map)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Environmental Sensitivity Index (ESI) maps are an integral component in oil-spill contingency planning and assessment. They serve as a source of information in the...

  5. Characterization of pre-hispanic pigments by modern analytical techniques; Caracterizacion de pigmentos prehispanicos por tecnicas analiticas modernas

    Energy Technology Data Exchange (ETDEWEB)

    Ortega A, M

    2003-07-01

    In this work, the study of mural painting pigments from two archaeological sites (The Great Temple in Mexico city and Cacaxtla) was performed to know their materials composition, identify their structural characteristics and properties by using modern analytical techniques. Blue, ochre, red and black pigments of Mexica culture (1325-1521 a.C. / late Post Classic period); blue, ochre, red, brown, pink, green and white of Olmeca- Xicalanca culture (700-900 a.C. / Epiclassic period) were studied. Data about materials used, technological evolution, mineralogical background, cultural interchange and origin was obtained. Environmental exposition of these paintings since their discovering has produced changes and damage on their materials. Therefore, stability of some pigments has been notorious, ''Maya Blue'' specially presents extraordinary resistance to diluted and concentrated acids and alkalis including boiling condition, acqua regia, solvents, oxidant and reducing agents, moderate heat and biocorrosi6n; for that reason its study was emphasized. ''Maya Blue'' pigment was synthesized in laboratory using the processes described by historic sources (with indigophera suffruticosa leaves and synthetic indigo) up to obtain a stable pigment including acqua regia action. Clay matrix sorbs nearly 0.4 weight percent of organic dye, which cover 79% of palygorskita surface area. (Author)

  6. Electrical characterization of a laminar manganese oxide type birnessite; Caracterizacion electrica de un oxido de manganeso laminar tipo birnesita

    Energy Technology Data Exchange (ETDEWEB)

    Arias, N. P.; Becerra, M. E.; Giraldo, O., E-mail: ohgiraldoo@unal.edu.co [Universidad Nacional de Colombia, Sede Manizales, Facultad de Ciencias Exactas y Naturales, Laboratorio de Materiales Nanoestructurados y Funcionales, Carrera 27 No. 64-60, 170004 Manizales (Colombia)

    2015-07-01

    This paper records the characterization of a manganese oxide synthesized by solid state routes which is analogous to natural mineral called birnessite. The analysis of X-ray diffraction and average oxidation state of manganese show that the material has a lamellar structure containing manganese in oxidation states (+4) and (+3). The results of electron microscopy along with surface area and pore size measurements reveal the presence of micro and meso pores in the material. Impedance spectroscopy suggests that high frequency electrical conduction occurs in the volume and on the border of the aggregates; in contrast, ionic conductivity at low frequencies was associated with potassium ions located in the interlaminar region. Ac conductivity values at low frequencies were 1.599 x 10{sup -6} Ω{sup -1} cm{sup -1} and 6.416 x 10{sup -5} Ω{sup -1} cm{sup -1} at high frequencies. These values are associated with an increased probability of electron jumping as frequency increases. These findings contribute to the understanding of electrical conduction processes and provides important information about its potential applications. As a result, this research will prove relevant in the field of batteries, super capacitors and heterogeneous catalysis, among others. (Author)

  7. Applications of the Raman spectroscopy in the materials characterization; Aplicaciones de la espectroscopia Raman en la caracterizacion de materiales

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez S, S. (ed.) [IPN, Centro de Investigacion y de Estudios Avanzados, Unidad Queretaro, Libramiento Norponiente No. 2000, Fracc. Real de Juriquilla, 76230 Queretaro (Mexico); Escobar A, L. (ed.) [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Camacho L, M. A. (ed.) [Universidad Autonoma del Estado de Mexico, Instituto Literario No. 100, Col. Centro, 50000 Toluca, Estado de Mexico (Mexico)

    2011-07-01

    The study field of the science and technology of surfaces and materials have been of primordial importance in the last years due to the impact that they have the knowledge that it generates in diverse areas. For this reason, the Mexican Society of Science and Technology of Surfaces and Materials has focused a good part of their investigation activities toward the materials science and technology development. Inside the investigation fields carried out by members of this Society, are the following: semiconductors, thin films, hard coatings, deposit techniques, plasmas, biomaterials, Ab-initio calculations, characterization techniques, photo-thermal properties, solar cells, nano science, magnetism, superconductivity and related topics. Among the techniques used for this purpose is the Raman Spectroscopy (Rs), which has demonstrated to be a powerful and versatile tool in the materials study. In the last three congresses that the Society has organized, an average of 42 works related with this topic have been presented, what gave the rule to prepare this book whose objective is on one hand diffusing part of the works that carry out different groups integrated with members of the Society that use the Rs like an important tool in its investigation work. A second objective is that it can serve like support to the students that begin to be involved, or that they are already involved, in topics where the Rs can have a decisive paper in the development of its projects. It is also expected that some of the topics included in the book are of utility for professors and researches that already uses the Rs, or that it can be of help for those who are beginning in this technique as alternative or like complementary analysis tool. (Author)

  8. Quantitative Characterization of Phosphor Detector for Fusion Plasmas; Caracterizacion Cuantitativa de Detectores Luminiscentes para Plasmas de Fusion

    Energy Technology Data Exchange (ETDEWEB)

    Baciero, A; Zurro, B; McCarthy, K J

    2004-07-01

    Experiments made to characterize phosphor screens with application as broadband radiation detectors, are described. Several radiation sources, covering the spectral range between the ultraviolet and X ray, were used. In addition, details are given of three original phosphor-screen-based detectors that were designed for use as broadband detectors in magnetically confined fusion devices. The first measurements obtained with these detectors in plasmas created in the TJ-II stellarator device are presented together with the analysis performed. (Author)

  9. CARACTERIZACION DE LAS CONCEPCIONES SOBRE MEDIO AMBIENTE EN ESTUDIANTES Y PROFESORES DE UN PROGRAMA DE FORMACION INICIAL

    Directory of Open Access Journals (Sweden)

    Sergio Andres Yepes Conde

    2015-12-01

    Full Text Available El trabajo se desarrolla como una propuesta de modalidad de grado para obtener el título de Licenciatura en Ciencias Naturales: Física, Química y Biología en la Universidad Surcolombiana. Se aborda la investigación de las concepciones sobre medio ambiente en estudiantes de practica I, II y profesores de la Licenciatura en Ciencias Naturales, con el propósito de realizar una caracterización y proponer recomendaciones acerca de las concepciones que se presenta. Para lograrlo se proponen unas fases en la investigación, las cuales evidencian las diferentes etapas que se deben cumplir para la realización del trabajo y alcanzar el objetivo de caracterizar las concepciones sobre medio ambiente. El trabajo se hará tomando una población de aproximadamente 30 personas, las cuales comprenden estudiantes de práctica del periodo de estudio 2015-B, y los profesores de planta y catedráticos de la licenciatura.

  10. Synthesis and characterization of the natural and burned hydrotalcite; Sintesis y caracterizacion de la hidrotalcita natural y calcinada

    Energy Technology Data Exchange (ETDEWEB)

    Granados C, F. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2006-07-01

    The synthesis and the structural and surface properties of the natural and burned hydrotalcite using salts of AlCl{sub 3} and MgCl{sub 2}.6H{sub 2}O its were studied. Its were used those analysis of BET, IR, XRD, TGA and SEM to characterize these materials. The obtained product was identified as the natural or carbonated hydrotalcite of chemical formula Mg{sub 6}Al{sub 2}(OH){sub 16}CO{sub 3}.4H{sub 2}O. The hydrotalcite was roasted at 500 C during 5 h and the was obtained roasted hydrotalcite (HTC) that is a material of high selectivity toward the anions that it can be efficiently used as adsorbent material in studies of adsorption for the treatment of anionic radioactive waste present in watery solution. (Author)

  11. CARACTERIZACION DE GENES DESHIDRINA EN EUCALYPTUS GLOBULUS CUYA EXPRESION ES INDUCIDA POR LA ACLIMATACION A BAJA TEMPERATURA

    OpenAIRE

    FERNANDEZ REYES, MARTA ALEJANDRA

    2011-01-01

    Eucalyptus globulus es una especie importante para la producción de pulpa de madera en Chile, sin embargo presenta una gran sensibilidad a temperaturas de congelamiento. Durante los últimos años, muchos estudios han enfocado sus esfuerzos en dilucidar los mecanismos que regulan la respuesta de las plantas a baja temperatura, mediante el análisis de la expresión génica. En el presente trabajo se estudia la expresión de genes deshidrina durante el proceso de aclimatación a baja temperatura y...

  12. CARACTERIZACION DE GENES DESHIDRINA EN EUCALYPTUS GLOBULUS CUYA EXPRESION ES INDUCIDA POR LA ACLIMATACION A BAJA TEMPERATURA

    OpenAIRE

    FERNANDEZ REYES ; MARTA ALEJANDRA; FERNANDEZ REYES ; MARTA ALEJANDRA

    2011-01-01

    Eucalyptus globulus es una especie importante para la producción de pulpa de madera en Chile, sin embargo presenta una gran sensibilidad a temperaturas de congelamiento. Durante los últimos años, muchos estudios han enfocado sus esfuerzos en dilucidar los mecanismos que regulan la respuesta de las plantas a baja temperatura, mediante el análisis de la expresión génica. En el presente trabajo se estudia la expresión de genes deshidrina durante el proceso de aclimatación a baja temperatura y la...

  13. SINTESIS, CARACTERIZACION Y ELECTRO-OXIDACION DE 2,2- DITIENIL DERIVADOS, EFECTO DE LA FUNCIONALIZACION SOBRE LAS PROPIEDADES ELECTRICAS

    OpenAIRE

    BROVELLI SEPULVEDA, FRANCISCO ANTONIO

    2002-01-01

    Desde el descubrimiento de la conducción eléctrica en sistemas poliméricos, se han realizado muchos esfuerzos con el propósito de mejorar tanto la conductividad como la resistencia mecánica de estos materiales, sin embargo, en la última década, se ha manifestado un gran interés por los sistemas semiconductores para el desarrollo de nuevos dispositivos, como por ejemplo, diodos emisores de luz (OLED). Debido a la versatilidad estructural que presentan los polímeras, se ha propuesto la sí...

  14. Morphometric characterization in basins affected by the mining industry; Caracterizacion morfometrica en cuencas hidrologicas afectadas por la mineria

    Energy Technology Data Exchange (ETDEWEB)

    Moreno Bortons, J.; Alonso Sarria, F.; Romero Diaz, A.; Belmonte Serrato, F.

    2009-07-01

    The intensive exploitation in the mining district of Cartagena la Union during recent centuries has generated a huge amount of waste scattered throughout the Sierra Minera. These debris act a dangerous pollution agent in the drainage network because the generated runoff erodes and disperse these wastes that are highly contaminated by heavy metals. In this way, the drainage networks of the study area been characterized to assess the production of runoff in basins which are sterile deposits, using the method of the Geomorphologic Unit Hydrography (GUH). The peak flows that have been obtained, taking into account the erodibility of soils, are capable of carrying large amounts of pollutants into the two main outlet areas (Mar Menor and Mediterranean Sea), meaning an important source of pollution int two sites of high ecological value. (Author) 6 refs.

  15. Dosimetric characterization of computerized tomography of 64 channels; Sobre la caracterizacion dosimetrica de un tomografo computarizado de 64 cortes

    Energy Technology Data Exchange (ETDEWEB)

    Gimeno-Fernandez, V.; Sotil-Baylos, J.; Garcia-Pazos, M.; Garcia-Pena, P.

    2006-07-01

    As a first step in the evaluation of effective dose to patients in Computed Tomography (CT) examinations, the purpose of this work was the assessment of the dose delivered by a new multislice scanner of 64 channels (Philips Brilliance 64c). This was done through the measurement of the CT Dose Index free in air, normalized to the unit of applied charge, using different beam collimations and tube voltages. Fitting nonlinear models to the observed data, kilo voltage and over beaming (penumbra) parameters have been elicited. The kilo voltage exponent of the relationship between CT dose index and kilo voltage varies from 2,84 to 2,88. The obtained penumbra with was 2,04 nm. Finally, corrections factors that must be applied to the measured dose indexes as a function of the applied collimation have been established from the estimated analytical relationships. (Author)

  16. Experimental Setup to Characterize Bentonite Hydration Processes; Diseno experimental para la caracterizacion de los procesos de hidratacion de la bentonita

    Energy Technology Data Exchange (ETDEWEB)

    Bru, A.; Casero, D.; Pastor, J.M.

    2001-07-01

    We present an experimental setup to follow-up the hydration process of a bentonite. Clay samples, of 2 cm x 12 cm x 12 cm, were made and introduced in a Hele-Shaw cell with two PMM windows and two steel frames. In hydration experiments, a fluid enters by an orifice in the frame, located both at the top and the bottom of the cell, to perform hydration in both senses. To get a uniform hydration we place a diffuser near the orifice. Volume influxes in hydration cells are registered in time. The evolution of the developed interface was recorded on a videotape. The video cameras was fixed to a holder so that the vertical direction in the monitor was the same as the direction of the larger extension of the cell. (Author) 6 refs.

  17. Characterization of AMC commercial bricks with different alumina qualities; Caracterizacion de ladrillos comerciales AMC con diferentes calidades de alumina

    Energy Technology Data Exchange (ETDEWEB)

    Muñoz, V.; Camerucci, Maria A.; Martinez, A.G. Tomba [Instituto de Investigaciones en Ciencia y Tecnologia de Materiales (INTEMA), CONICET - Fac. de Ingenieria (UNMdP), Mar del Plata (Argentina)

    2011-07-01

    The study of commercial bricks Al{sub 2}O{sub 3}-MgO-C (AMC) has some advantages over the analysis of materials prepared in the laboratory, but requires a complete characterization. This paper presents the results of the characterization of commercial bricks AMC with different types of alumina aggregates used in ladles floor. The same is done by several complementary techniques: XRD, DTA / TGA, EPR, volume density and apparent porosity, dilatometric analysis, microstructural analysis by low magnification and scanning electron microscopy (SEM) coupled with analysis Energy dispersive X-ray (EDX) and determination of mechanical properties at room temperature (Young's modulus, stress and strain at fracture). The main characteristics and differences in the composition and microstructure, essential data for further analysis of the mechanical behavior and resistance to slag attack of these refractories, are determined. (author)

  18. ¿Crisis o transición? Caracterizaciones intelectuales. Del dualismo argentino en la apertura democrática

    Directory of Open Access Journals (Sweden)

    Visacovsky, Sergio E

    2005-06-01

    Full Text Available This article presents an analysis of the conceptual organization of the "democratic transition" model, through which an important sector of social scientists represented the military dictatorship crisis in Argentina in 1982, and interpreted its advent and ending, to guide the society towards its definitive democratization. This model was based on ideas and conceptual structures produced and used in the Argentine society to describe and to interpret the political process. We will explain that the notion of "crisis" was replaced for the democratic transition model; this paradigm was made according to the classic frames of Argentine thinking, and for this reason it was not only an interpretative frame to the inauguration of a new era and the final overcoming of the democratic instability, but also a perspective on political past and the causes of “authoritarianism”.

    Este trabajo presenta un análisis de la organización conceptual del modelo de “transición a la democracia” mediante el cual un amplio sector de científicos sociales conceptualizó la crisis de la última dictadura militar en la Argentina en 1982, e interpretaron su advenimiento y desenlace, para guiar a la sociedad hacia su definitiva democratización. Este modelo estaba sustentado en nociones y estructuras conceptuales producidas y empleadas en la sociedad argentina para describir e interpretar el proceso político. La noción de “crisis” revirtió en una aplicación del modelo de transición a la democracia que, aún cuando se propuso como un marco interpretativo volcado a la inauguración de una nueva era y a la superación definitiva de las interrupciones democráticas, conllevó una perspectiva sobre el pasado político y, en especial, sobre las causas del “autoritarismo”, que se forjó dentro de los moldes clásicos del pensamiento argentino.

  19. CARACTERIZACION DE RIZOBACTERIAS PROMOTORAS DEL ENRAIZAMIENTO DE ESTACAS DE EUCALYPTUS GLOBULUS LABILL. : MECANISMOS DE ACCION Y FLUCTUACION POBLACIONAL

    OpenAIRE

    DIAZ PERALTA, KATY PAULINA; DIAZ PERALTA, KATY PAULINA

    2009-01-01

    Las plantaciones de Eucalyptus spp en Chile, son altamente valoradas en el mercado mundial, su producción se basa en la propagación vegetativa de plantas en viveros, a través de estacas y miniestacas; sin embargo, ex iste una variabilidad en el potencial del enraizamiento entre clones de especies e híbridos del género, lo cual no permite obtener el total de plantas en los programas de producción clonal. Diversos estudios han demostrado que bacterias rizosféricas denominadas bacterias promotor...

  20. Glass characterization to assess the airborne sound isolation; Caracterizacion de vidrios para la evaluacion del aislamiento acustico a ruido aereo

    Energy Technology Data Exchange (ETDEWEB)

    Alba Fernandez, J.; Rey Tormos, R. del; Ramis Soriano, J.; Berto Carbo, L.

    2012-11-01

    The main contribution of this paper is the formulation of an alternative to experimental determination of loss factor and, consequently, to improve the predictions of airborne sound insulation for any type of monolithic or laminated glass. In addition, a review of the standards related to measurement of mechanical parameters of glass is carried out, with particular interest in laminated glass Indeed, one of the problems that arise in the current context of building acoustics is to meet the requirements of facades airborne sound insulation of existing Building Technical Code (BTC). It is known that the blind and the hollow part of the facade should be distinguished. The weakest part regarding to airborne sound insulation is the empty one (consisting of glass, woodwork and other elements). Choosing an adequate woodwork makes the glass surface become the limiting factor. The Constructive Elements Catalog (CEC) of the BTC, the UNE-EN 12758:2011 standard, as well as some, increasingly, data vendors provide information about airborne sound insulation for monolithic glass, laminated glass and double glazing. In the case of laminated glass, these data are limited only to those with a single intermediate layer, and also nonacoustic. Can therefore be said that there is a gap of knowledge in this regard. To obtain reliable predictions of airborne sound insulation of multilayer partitions, such as laminated glass, mechanical characteristics must be known, being loss factor one of the most important. (Author) 7 refs.

  1. Chemical characterisation of zircon-cadmium sulfoselenide ceramic pigments; Caracterizacion quimica de pigmentos ceramicos a base de sulfoseleniuro de cadmio

    Energy Technology Data Exchange (ETDEWEB)

    Gazulla Barreda, M. F.; Rodrigo Edo, M.; Blasco Roca, E.; Orduna Cordero, M.

    2013-07-01

    The present paper addresses the development of a methodology that allows the complete chemical characterisation of zircon cadmium sulfoselenide ceramic pigments including minor and major elements. To develop the methodology, five zircon-cadmium sulfoselenide pigments with different hues were selected, studying the different measurement process steps, from sample preparation to the optimisation of the measurement of the different components of the pigments by spectroscopic techniques (WD-XRF and elemental analysis by combustion and IR detection). The chemical characterisation method developed was validated with synthetic standards prepared from the mixture of certified reference materials and pure oxides because no certified referenced materials of this type of pigments were commercially available. The developed method can be used for a complete chemical characterization of zircon-cadmium sulfoselenide ceramic pigments with a very low uncertainty for all the elements analysed. (Author)

  2. Clinicoepidemiologic characterization and endoscopy in patients with colorectal cancer; Caracterizacion clinico-epidemiologica y endoscopica en pacientes con cancer colorrectal

    Energy Technology Data Exchange (ETDEWEB)

    Hano Garcia, Olga Marina; Wood Rodriguez, Lisette; Villa Jimenez, Oscar Manuel, E-mail: olga.hano@infomed.sld.c [Instituto Nacional de Gastroenterologia, La Habana (Cuba)

    2010-07-01

    Colorectal carcinoma is recognized as the second death cause from cancer in most of developed countries; the increasing exposure to risk factor such as smoking, changes in diet, in lifestyles, as well as environmental and infectious factors is conductive to its morbidity and mortality increase. A prospective and descriptive study was conducted in 65 patients older than 18 years seen from April, 2007 to April, 2008 in the Endoscopy Service of the National Institute of Gastroenterology, diagnosed with colorectal carcinoma by colonoscopy and histology. In collection form were registered: sex, age, personal backgrounds of colon cancer, polyps, intestinal inflammatory disease and cholecystectomy; family backgrounds of colon cancer or another location; toxic habits: smoking and alcoholism; diet as regards: vegetal fiber ingestion and animal fat; anatomic location of cancer and histology. We conclude that there was predominance of female sex, the more frequent diagnosis age was between 60 and 70 years. The personal background of colon polyp and the family background of colon cancer were the more frequent. There was also predominance of smokers and heavy drinkers with or without effect. There was a great ingestion of animal fat and few ingestion of vegetal fiber. The more frequent anatomical location was the rectosygmoid, where the histological colon adenocarcinoma had the greater frequency

  3. Clinic-surgical characterization of the colorectal cancer in inpatients;Caracterizacion clinico quirurgica del cancer colorrectal en pacientes ingresados

    Energy Technology Data Exchange (ETDEWEB)

    Alejo Concepcion, Osvaldo; Castillo Lamas, Libardo; Umpierrez Garcia, Ibis [Hospital Militar Docente ' Dr Mario Munnoz Monroy' , Matanzas (Cuba)

    2009-07-01

    The colorectal cancer presents high incidence. This pathology occupies the fifth place among the neoplasias in both sexes in Cuba. With the objective of characterizing this disease we carried out a descriptive transversal study at the service of General Surgery of the University Military Hospital of Matanzas 'Dr. Mario Munnoz Monroy', in the period from January 2001 to January 2005, studying age, sex, familiar oncological antecedents, presentation form, localization and diagnosis of the tumor, and also the surgical technique used in the treatment. The results showed predominance of the male sex in ages between 60 and 69 years old, different symptoms depending on the localization, predominance of the rectal cancer, and others. It was concluded that there is a delay between the beginning of the symptoms and the diagnosis, considerably diminishing the healing possibilities and survival

  4. Characterization and packaging of disused sealed radioactive sources; Caracterizacion y acondicionamiento de fuentes radiactivas selladas en desuso

    Energy Technology Data Exchange (ETDEWEB)

    Aguilar, S.L. [Instituto Boliviano de Ciencia y Tecnologia Nuclear (IBTEN), La Paz (Bolivia, Plurinational State of)

    2013-07-01

    In Bolivia are generated disused sealed sources and radioactive waste resulting from the use of radioactive materials in industrial, research and medicine. The last includes the diagnosis and treatment. Whereas exposure to ionizing radiation is a potential hazard to personnel who applies it, to those who benefit from its use or for the community at large, it is necessary to control the activities in this field. The Instituto Boliviano de Ciencia y Tecnologia Nuclear - IBTEN is working on a regional project from International Atomic Energy Agency - IAEA, RLA/09/062 Project - TSA 4, Strengthening the National Infrastructure and Regulatory Framework for the Safe Management of Radioactive waste in Latin America. This Project has strengthened the regulatory framework regarding the safe management of radioactive waste. The aim of this work was focused primarily on the security aspects in the safe management of disused sealed sources. The tasks are listed below: 1. Characterization of disused sealed sources 2. Preparation for transport to temporary storage 3. Control of all disused radioactive sources. (author)

  5. Preparation and characterisation of mixed silicon oxycarbide materials; Preparacion y caracterizacion de materiales de oxicarburo de silicio mixtos

    Energy Technology Data Exchange (ETDEWEB)

    Tellez, L.; Tamayo, A.; Mazo, M. A.; Rubio, F.; Rubio, J.

    2010-07-01

    In this work different mixed Silicon oxicarbide materials have been prepared. Si, Si-Ti, Si-Zr and Si-Al oxicarbide materials have been obtained from pyrolisis at 1000 degree centigrade and 1300 degree centigrade of the respective preceramic materials. After pyrolisis X, D and T units of the oxycarbide structure have been observed in such materials. They show the presence of Si-C and Si-O bonds in a given material. The characterization has been carried out by means of FT-IR, Raman NMR {sup 2}9Si, NMR {sup 1}3C and XRD. The formation of Si-Ti, Si-Zr and Si-Al bonds has been estimated in accordance with the decrease of the Si-O-Si wave number observed in the FT-IR spectra. Si and Si-Ti oxycarbide materials do not lead to crystallisation after pyrolisis at highest temperatures, however for Si-Zr and Si-Al oxycarbide materials different crystalline phases have been observed. All pyrolised materials present free and carbidic carbon. After pyrolisis at 1300 degree centigrade the free carbon reacts with Si-O bonds to form SiC{sub 4} groups which must be assigned to nucleus of the {beta}-SiC crystals. (Author)

  6. Characterization of the Novillo Tokamak in main discharge regime; Caracterizacion del Tokamak Novillo en regimen de descarga principal

    Energy Technology Data Exchange (ETDEWEB)

    Lopez C, R.; Melendez L, L.; Chavez A, E.; Colunga S, S.; Valencia A, R.; Gaytan G, E

    1992-07-15

    The analytical procedure to carry out the establishment of the discharge in a Tokamak including: a) Ionization, b) Diffusion losses, recombination, union, drift speed, spurious fields, and c) Electric field is presented. In an experimental way a procedure settles down by means of which it is characterized the plasma, specially a new characteristic discharge parameter is settled down and it is the plasma current by the duration of the (I{sub p}t) discharge. (Author)

  7. Characterization dosimetry of applicators Valencia using different techniques; Caracterizacion dosimetrica de los aplicadores Valencia mediante diferentes tecnicas

    Energy Technology Data Exchange (ETDEWEB)

    Ferrer Garcia, C.; Huertas, C.; Huerga Cabrerizo, C.; Corredoira Silva, E.; Serrada Hierro, A.

    2013-07-01

    Valencia applicators, connected to a charging system deferred micro Selectron-HDR (Elekta-Nucletron), are used for treating small skin lesions, being an alternative to treatments with electron beams or orthovoltage equipment of X ray. These applicators are a modification of Leipzig applicators, consisting of a flatter filter, which flattens the dose distribution in the area of treatment [1,2]. In the present study are considered applicators with diameters of 2 and 3 cm (VH2 and ht5), with the parallel to the treatment area source. Due to the electronic pollution on the walls of the applicator, treatments are performed with a plastic cap. In this study are commissions Valencia applicators, checking the various options proposed in the literature. (Author)

  8. Characterization of pre-hispanic pigments by modern analytical techniques; Caracterizacion de pigmentos prehispanicos por tecnicas analiticas modernas

    Energy Technology Data Exchange (ETDEWEB)

    Ortega A, M

    2003-07-01

    In this work, the study of mural painting pigments from two archaeological sites (The Great Temple in Mexico city and Cacaxtla) was performed to know their materials composition, identify their structural characteristics and properties by using modern analytical techniques. Blue, ochre, red and black pigments of Mexica culture (1325-1521 a.C. / late Post Classic period); blue, ochre, red, brown, pink, green and white of Olmeca- Xicalanca culture (700-900 a.C. / Epiclassic period) were studied. Data about materials used, technological evolution, mineralogical background, cultural interchange and origin was obtained. Environmental exposition of these paintings since their discovering has produced changes and damage on their materials. Therefore, stability of some pigments has been notorious, ''Maya Blue'' specially presents extraordinary resistance to diluted and concentrated acids and alkalis including boiling condition, acqua regia, solvents, oxidant and reducing agents, moderate heat and biocorrosi6n; for that reason its study was emphasized. ''Maya Blue'' pigment was synthesized in laboratory using the processes described by historic sources (with indigophera suffruticosa leaves and synthetic indigo) up to obtain a stable pigment including acqua regia action. Clay matrix sorbs nearly 0.4 weight percent of organic dye, which cover 79% of palygorskita surface area. (Author)

  9. Characterization and morphology of solids suspended in rain water; Caracterizacion y morfologia de solidos suspendidos en agua de lluvia

    Energy Technology Data Exchange (ETDEWEB)

    Iturbe G, J.L.; Lopez M, B.E.; Torre O, J. De la [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, Mexico D.F. (Mexico)

    2000-07-01

    This work presents the results obtained from the analysis of rain water in Mexico. The study treats over the characterization and morphology of the solids suspended in form of particles in the atmosphere. The solids suspended were obtained of the pluvial precipitations after these have been centrifuged. Subsequently of the separation, the particulate matter was analysed by Sem and X-ray dispersive energy.

  10. Microstructural characterization of copper based alloys produced by reactive milling; caracterizacion microestructural de aleaciones base cobre obtenidas mediante molienda reactiva

    Energy Technology Data Exchange (ETDEWEB)

    Palma, R.; Sepulveda, A.; Zuniga, A.; Donoso, E.; Dianez, M. J.; Criado, J. M.

    2010-07-01

    The micro and nano structure of Cu-Al, Cu-V and Cu-Ti alloys produced by reactive milling were analyzed using X-ray diffraction (XRD) and transmission electron microscopy (TEM). Samples with different milling times (t= 0, 10, 20 and 30 h) were considered. The grain size, dislocation density and residual micro strain were evaluated form the XRD data using the Williamson-Hall and Klug-Alexander methods. The evolution of texture as a function of milling time was also studied using XRD. It was found, using TEM, that the grain size and dispersoid size were nano metric in all three alloys considered. (Author) 12 refs.

  11. Introduction to materials science: Preparation and characterization techniques. Introduccion a la ciencia de los materiales: tecnicas de preparacion y caracterizacion

    Energy Technology Data Exchange (ETDEWEB)

    Albella, J.M.; Cintas, A.M.; Miranda, T.

    1993-01-01

    The materials science in this book is analyzed. Through 18 chapters the materials type, their structure, chemical reactions, mechanical properties are studied. Also optical properties of materials, magnetic properties, thin films, electronic microscopy and electric optic spectroscopy are analyzed.

  12. Synthesis by plasma and characterization of compounds derived from polyacetylene; Sintesis por plasma y caracterizacion de compuestos derivados del poliacetileno

    Energy Technology Data Exchange (ETDEWEB)

    Vasquez O, M

    2004-07-01

    This work presents a study on, the synthesis by plasma and the characterization of an aliphatic conjugated polymer, polyacetylene-chlorinated (Pac), and two aromatic polymers, Poly pyrrole (P Py-Cl) and Poly thiophene (Pth-Cl) synthesized with chlorine and the electrical conductivity. The last two polymers were synthesized to compare the chlorine-polymer interaction in aliphatic and aromatic polymers synthesized by plasma and their repercussion on the electrical transport of charges in the material. The structure and morphology of the polymers were studied using scanning electron microscopy (Sem), energy dispersive spectroscopy (EDS), infrared spectroscopy (Ft-IR), conductivity analysis and X-Ray photon spectroscopy (XPS). The results showed that Pac is soluble in acetone and other organic solvents, which indicates a low proportion of crosslinking in the polymers. This point is important because the crosslinking reduces the electrical conductivity in the material. The Pac conductivity is in the range of 1 x 10{sup -12} to 6 x 10{sup -4} S/cm in the internal of 35- 90% of relative humidity. A possible mechanism for the transport of electrical charges in Pac is by means of the double and simple conjugated bonds in the polymers. Pth-Cl and P Py-Cl present electric conductivity in the interval of 9 x 10{sup -5} to 1 x 10{sup -2} S/cm and show a great dependence on the relative humidity. The chlorine addition in these polymers was through simultaneous polymerization with chloroform. This last compound can decompose if the energy of the plasma is relatively high, and the fragments can link to the polymer in a hybrid process of copolymerization. An important point of this work is that the polymer is soluble, a difference of the obtained via plasma as the poli aniline, P Py-CI and Pth-Cl both studied in this work. If took in account that the Pac is single the monomer and that P Py-Cl and Pth-CI is affected by the chlorine that modifies the conductivity of the material, then Pac presents an electrical conductivity greater that P Py-Cl and Pth-Cl. (Author)

  13. Hydrogeological characterization of the Nador Plio-Quaternary aquifer, Tipaza (Algeria); Caracterizacion hidrogeologica del acuifero pliocuaternario de Nador, Tipaza (Argelia)

    Energy Technology Data Exchange (ETDEWEB)

    Bouderbala, A.; Remini, B.; Pulido-Bosch, A.

    2014-06-01

    This paper focuses on the hydrogeological and hydrochemical knowledge of the Nador Plio-Quaternary aquifer in Tipaza, situated along the Algerian coastline. It includes the identification of the hydrodynamic aquifer, hydrogeological and piezometric characteristics and, finally, an overview of the hydro-geochemistry of the area. We carried out this study between 2008 and 2013, with piezometric and hydrochemical monitoring of 24 wells in the study area. The physicochemical analysis of water shows that 25 % of the wells in the coastal zone have values of electrical conductivity greater than 3000 μS/cm The Mg{sup 2}+/Ca{sup 2}+ ratio is also higher than one and there are sodium chloride facies due to the mix of freshwater with seawater exceeding 10 % in some places. However, the comparison of the salinity of the groundwater during the period 2008-2013 with 1988-2004 indicates that there is a low dilution due to the reduction of pumping in the aquifer after the construction of the Boukourdane dam. There has also been a more rainy period and a possible return flow from irrigation in the area. (Author)

  14. Theoretical characterization of the spatial resolution intra-operative probes; Caracterizacion teorica de la resolucion espacial de sondas intraoperatorias

    Energy Technology Data Exchange (ETDEWEB)

    Agramunt Chaler, S.; Jurado Bruggeman, D.; Munoz Montplet, C.

    2013-07-01

    This work intends to check that the characterization of the spatial profiles obtained by a an intraoperative probe in the presence of a point source is possible enough making use only of the parameters down time sensitivity and opening of the collimator. (Author)

  15. Experimental characterization. Thermal and solar performance of houses built; Caracterizacion experimental. comportamiento termico y solar de viviendas construidas

    Energy Technology Data Exchange (ETDEWEB)

    Carrilo, A.; Jurado, L.; Molina, J. C.; Druet, L.

    2011-07-01

    In this communication we describe the calibration of a simulation model of a house. is the Energy Plus simulation program, and the experimental procedure is based on the method PSTAR (Subbarao, 1988) which are obtained adjustment factors that provide a quantitative interpretation of the discrepancies. (Author)

  16. Characterization of Pt catalysts supported in mixed oxides; Caracterizacion de catalizadores de Pt soportado en oxidos mixtos

    Energy Technology Data Exchange (ETDEWEB)

    Perez H, R.; Garcia C, M.A.; Gomez C, A.; Diaz, G. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2000-07-01

    The catalytic supports TiO{sub 2}, ZrO{sub 2} and TiO{sub 2}-ZrO{sub 2} were prepared by the sol-gel technique. The incorporation of Pt to the supports was by the classical impregnation method. The catalytic materials were characterized (Pt/TiO{sub 2}, Pt/ZrO{sub 2} and Pt/TiO{sub 2}-ZrO{sub 2}) by diverse techniques to determine: the texture (BET), evolution of the catalytic materials synthesised after drying and calcination (Infrared spectroscopy) and by Thermogravimetric analysis. (Author)

  17. Influence of Ce(III/Ce(IV - supplements on the Characteristics of Humidity Sensors with TiO2 Films Prepared via a Sol-gel Method

    Directory of Open Access Journals (Sweden)

    Kozhukharov, S.

    2013-04-01

    Full Text Available Humidity sensors have been prepared via a sol-gel method to deposit TiO2 films with additions of Ce-compounds on alumina substrates, with interdigitated silver palladium electrodes. Observations by scanning electron microscopy (SEM were performed in order to determine the surface morphology of the respective layers. Structural and compositional characterization was done by X-ray diffraction analysis (XRD, and energy dispersive X-ray spectroscopy (EDX for investigation of the relation between the film structures and the parameters of the respective sensors. The influence of Ce-compounds on the electrical characteristics of the samples as humidity sensing elements has been evaluated by an impedance analyzer.Los sensores de humedad han sido desarrollados mediante el método sol-gel para depositar películas superficiales basadas en TiO2 con adiciones de compuestos de cerio sobre sustratos de corindón y electrodos de aleación de plata y paladio. Se han realizado observaciones mediante el Microscopio Electrónico de Barrido (MEB para determinar la morfología superficial de las capas respectivas. Las caracterizaciones de la estructura y composición han sido realizadas mediante Difracción de Rayos X (DRX y espectroscopía de dispersión energética de rayos X (EDERX, con el fin de investigar la relación entre la estructura de las capas y los parámetros de los sensores respectivos. La influencia de los compuestos de cerio sobre las características eléctricas de los sensores de humedad obtenidos se ha evaluado mediante el análisis de impedancia eléctrica.

  18. Integrated stratigraphy, astronomical dating and proxy records of the Ain el Beida and Loulja sections (NW Morocco). Implications for regional climate change, glacial history and the Messinian Salinity Crisis. Geologica Ultraiectina (324)

    NARCIS (Netherlands)

    van der Laan, E.

    2010-01-01

    This Ph.D. thesis aims to provide a better understanding of the origin of sedimentary colour cycles in the Bou Regreg area in NW Morocco. Sediments were deposited during the late Miocene and early Pliocene at times that the Mediterranean was isolated from the Atlantic during the Messinian salinity

  19. Evolução geologica do pre-cambriano da porção centro-leste da serra do Espigão meridional e metalogenese associada

    OpenAIRE

    Luiz Guilherme Knauer

    1990-01-01

    Resumo: A porção centro-leste da Serra do. Espinhaço Meridional é caracterizada principalmente por terrenos de idade Pré-Cambriana, incluindo seqüências do Arqueano (Complexo de Gouveia, de alto grau metamórfico, e Grupo Pedro Pereira, de baixo grau) e do Proterozóico (todas de baixo grau metamórfico: Grupo Costa Sena, Supergrupo Espinhaço sensu stricto, Seqüência Itapanhoacanga, Seqüência Serra do Sapo, Seqüência Jacem e Seqüência Serro), alem de diques e sills básicos metamorfisados em fáci...

  20. Fotointerpretation and geological integration of San Diego-El Naranjo thermal zone in the Nayarit State, Mexico; Fotointerpretacion e integracion geologica de la zona termal de San Diego-El Naranjo, Nayarit, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Castillo H, Daniel [Gerencia de Proyectos Geotermoelectricos de la Comision Federal de Electricidad, Morelia (Mexico)

    1996-01-01

    The lithological, structural and thermal characteristics of a zone located in the State of Nayarit, Mexico between the Sierra Madre Occidental (SMO) and the Llanura Costera del Pacifico (PCP) are presented. The SMO is constituted by both extrusive and intrusive rocks of Oligo-Miocene age whereas the PCP is formed by conglomerates and erosional products derived from the disintegration of these rocks. Nine thermal superficial manifestations were observed at the site, with temperatures ranging from 35 degrees celsius to 80 degrees celsius. The chemical nature of these geothermal fluids is sodium-sulfate with estimated deep temperatures of 185 degrees celsius. From the structural view point, the zone is affected by faults and fractures aligned NE-SW and NW-SE; these structural trends control the thermalism. On the other hand, a 20 x 20 km ring-shaped geologic feature was identified within the area, which may be associated with the SMO. [Espanol] Se presentan las caracteristicas litologicas, estructurales y termales de una zona del Estado de Nayarit, comprendida entre las Provincias de la Sierra Madre Occidental (SMO) y la Llanura Costera del Pacifico (PCP). La primera comprende rocas igneas, intrusivas y extrusivas, de edad oligomiocenica. La segunda agrupa productos erosivos y conglomeraticos producidos por la desintegracion de las rocas; su edad se considera del Cuaternario. En la zona existen nueve localidades termales con un intervalo de temperatura de 35 grados celsius a 80 grados celsius, y un caracter quimico sulfatado-sodico. Por geotermometria se obtuvo una temperatura de 185 grados celsius. Estructuralmente dominan las fallas y fracturas NE-SW y NW-SE, que afectan a todas las rocas expuestas y controlan tambien al termalismo. Dentro del area se identifico una geoforma circular de 20 x 20 km, que se considera asociada y controlada geneticamente por la SMO.

  1. Genetic and geological classification wetlands proposed. Application to the spanish wetlands included in the Ramsar convention; Propuesta de clasificacion genetico-geologica de humedales. Aplicacion a los humedales espanoles incluidos en el Convenio de Ramsar

    Energy Technology Data Exchange (ETDEWEB)

    Duran Valsero, J. J.; Garcia de Domingo, A.; Robledo Ardila, P.

    2009-07-01

    The classification represents the first step in the research of the wetlands. There are several types of classifications established according different criteria: geographic, genetic, geologic, functional, hydric, biologic and others. In this work we considered the genetic and geologic classifications criteria are the more suitable because the criteria used are very concrete, descriptive and its application should be easier to put into practice. Every group established in this type of classification determines the develop naturals conditions allowing us to establish the evolution guidelines and same main management lines. The criteria used to develop this classification have been fundamentally: geologic, geomorphologic, tectonics, stratigraphic, and hydrogeologic because these determine greatly the physical wetland characteristics (geometric parameters, hydric nourishment system, hydrochemical characteristics and others). The general characteristics, guidelines behavior of the wetland, and the early evolution of every group of wetland could be essentials to detect and identified those actuations modifying the natural evolution in each concrete wetland. In this work we are applying these classification criteria to the Spanish wetlands included in the Ramsar Convention (until February 2006), defining twelve types of basic wetlands according the geologic and genetic characteristics. (Author) 19 refs.

  2. Experimental methodology to study radionuclide sorption and migration in geological formations and engineered barriers of waste repositories; Metodologia experimental para estudios de sorcion y migracion de radionucleidos en formaciones geologicas y barreras de almacenamientos de residuos

    Energy Technology Data Exchange (ETDEWEB)

    Rojo Sanz, H.

    2010-07-01

    In Spain, the waste management options include either the possibility of a final storage in a deep geological repository (DGR) or the centralized temporal surface disposal (CTS). DGRs are based in a multi-barrier concept with the geological barrier and including the vitrified waste, the metal containers and engineered barriers such as compacted bentonite and cement-based materials. On the other hand, CTS mainly considers concrete and cement to confine the metal canisters containing the waste. Radionuclide migration will mainly take place by the existence of chemical concentration gradients being thus diffusion the main transport mechanism or by the existence of hydraulic gradients due to the existence of water-conductive fractures. Radionuclide sorption/retention on the materials composing the natural and engineered barriers is the fundamental process controlling contaminant migration. The evaluation of sorption parameters and the understanding of the different mechanisms leading to radionuclide retention are very important issues. The study of diffusion processes is very relevant as well. This paper describes the main experimental methodologies applied to analyse radionuclide transport in the different barriers of radioactive repositories. Particularly we focused on obtaining of retention parameters as distribution coefficients, kd, or retardation factors, Rf, and diffusion coefficients of radionuclides. (Author) 6 refs.

  3. HIPEROSTOSIS ESQUELÉTICA DIFUSA IDIOPÁTICA EN UNA COLECCIÓN OSTEOLÓGICA CONTEMPORÁNEA (LA PLATA, BUENOS AIRES, ARGENTINA / Difusse Idiopathic Skeletal Hyperostosis in a contemporary osteological collection (La Plata, Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Marcos Plischuk

    2015-06-01

    Full Text Available La Hiperostosis Esquelética Difusa Idiopática (DISH es una enfermedad caracterizada por provocar anquilosis entre cuerpos vertebrales, sumada a la osificación masiva de ligamentos y tendones en el resto del sistema esqueletal. El objetivo del presente trabajo es establecer la prevalencia de DISH en una colección osteológica documentada contemporánea y discutir rasgos patognomónicos y factores de riesgo asociados. A fin de establecer un diagnóstico se relevó, en 100 individuos adultos, la formación de bloques óseos de al menos tres vertebras fusionadas por la osificación de ligamento vertebral anterior. Se consideró además que no estuvieran comprometidos los espacios intervertebrales y la articulación sacroilíaca. En la zona extra espinal se registraron como evidencia complementaria la presencia de entesopatías. Como resultado del análisis se observaron seis individuos con DISH, sin diferencias significativas entre ambos sexos. El segmento vertebral principalmente afectado fue el torácico, los espacios intervertebrales no se vieron comprometidos en ningún caso y la articulación sacroilíaca tampoco presentó señales de osificación patológica; a la vez que se relevaron numerosas entesopatías. Las prevalencias observadas se deberían a la avanzada edad de los individuos analizados y las características nutricionales de la población de referencia.  Abstract  The diffuse idiopathic skeletal hyperostosis (DISH is a disease characterized by vertebral ankylosis, with massive ligaments and tendons ossification in the rest of the skeletal system. The aim of this study is to establish the prevalence of DISH in a well-documented and contemporary osteological collection, and to discuss pathognomonic features and associated risk factors. In order to establish the diagnosis, we registered, in 100 adults, the formation of bone blocks, with at least three fused vertebrae by ossification of the anterior vertebral ligament. It was also considered that were not compromise of the intervertebral spaces and sacroiliac joint. The extra-spinal area was analyzed as additional evidence because of enthesopathies.The results showed six individuals with DISH, with no significant differences between the sexes. The thoracic segment was the most affected, intervertebral spaces were not compromised in any way and the sacroiliac joint did not provide signs of ossification, while numerous enthesopathies were detected. The prevalences observed are due to the advanced age of the individuals analyzed and the nutritional characteristics of the reference population.

  4. Resuena el cuerpo: hacia una etnografía con cantantes de música popular en La Plata

    OpenAIRE

    Magri, María Gisela

    2013-01-01

    En este trabajo, exploraremos algunas líneas de análisis en torno a los primeros avances en el trabajo de campo que me encuentro desarrollando para mi proyecto de doctorado "Cantantes contemporáneos de música popular latinoamericana en La Plata”, cuyo objetivo general es analizar las prácticas y los procesos de construcción de identidades, corporalidad y voz, en cantantes varones y mujeres dentro del circuito de músicos populares de la ciudad. A partir del material, surgido en entrevistas rea...

  5. Estudio poblacional de prevalencia de anemia ferropénica en La Plata y sus factores condicionantes

    OpenAIRE

    Marín, Gustavo Horacio

    2006-01-01

    La anemia es una de las mayores causales de muerte en la población mundial, y constituye el problema nutricional más grave en el mundo. La anemia y la deficiencia de hierro afectan a aproximadamente mil ochocientos millones de personas. Entre los grupos más afectados figuran las mujeres en edad fértil debido a las pérdidas de sangre en las menstruaciones; las embarazadas, ya que tienen un aumento en las demandas de sangre que determina que los requerimientos de hierro de su organismo no pueda...

  6. Síntesis, estructura y propiedades de transporte de nuevos óxidos complejos de cobre, plata y plomo

    Directory of Open Access Journals (Sweden)

    Tejada-Rosales, E. M.

    2002-02-01

    Full Text Available A solid solution of formula Ag5Pb2-xCuxO6, (x = 0, 0.1, 0.3, 0.5 is reported. The synthesis was carried out by coprecipitation of Ag(I, Pb(II and Cu(II nitrates in alkaline media. The structure of the series is that of the parent Ag5Pb2O6, with Cu(II occupying part of the octahedral Pb(IV sites. This substitution induces interesting changes in the transport properties of the different members of the series, which range from metallic conductivity to semiconducting behavior. From Rietveld analysis for Ag5Pb1.5Cu0.5O6, the best fit is obtained for a model with Pb and Cu disordered occupying the octahedral site (Pm1, a = 5.8306(9 Å, c = 6.3430(6 Å, V = 187.37 Å3.

    Se presenta la síntesis y caracterización de la serie de disolución sólida Ag5Pb2-xCuxO6, (x = 0, 0.1, 0.3, 0.5. La síntesis se llevó a cabo mediante coprecipitación de los nitratos de Ag(I, Pb(II y Cu(II en medio básico. La estructura de la serie es la del óxido Ag5Pb2O6, con el Cu(II ocupando parcialmente los sitios octaédricos del Pb(IV. Esta sustitución induce cambios interesantes en las propiedades de transporte eléctrico de los miembros de la serie, que van desde conductividad metálica a comportamiento semiconductor. El análisis Rietveld para el óxido Ag5Pb1.5Cu0.5O6, mostró un modelo estructural óptimo en el que Pb y Cu comparten el sitio octaédrico en una distribución desordenada (Pm1, a = 5.8306(9 Å, c = 6.3430(6 Å, V = 187.37 Å3.

  7. Coalescence of silver unidimensional structures by molecular dynamics simulation; Coalescencia de estructuras unidimensionales de plata por simulacion dinamica molecular

    Energy Technology Data Exchange (ETDEWEB)

    Perez A, M.; Gutierrez W, C.E.; Mondragon, G. [ININ, 52750 La Marquesa, Estado de Mexico (Mexico); Arenas, J. [IFUNAM, 04510 Mexico D.F. (Mexico)

    2007-07-01

    The study of nanoparticles coalescence and silver nano rods phenomena by means of molecular dynamics simulation under the thermodynamic laws is reported. In this work we focus ourselves to see the conditions under which the one can be given one dimension growth of silver nano rods for the coalescence phenomenon among two nano rods or one nano rod and one particle; what allows us to study those structural, dynamic and morphological properties of the silver nano rods to different thermodynamic conditions. The simulations are carried out using the Sutton-Chen potentials of interaction of many bodies that allow to obtain appropriate results with the real physical systems. (Author)

  8. Género, turismo y exportación: ¿llamando a la plata en el Perú?

    Directory of Open Access Journals (Sweden)

    Jane Henrici

    2007-12-01

    Full Text Available El siguiente artículo es una descripción breve del caso de algunas mujeres de la región de Cusco, en Perú, involucradas en la producción o en la venta de objetos étnicos para el mercado turístico y para la exportación. El análisis muestra que, mientras que en su discurso sobre el turismo y el comercio los actores enfatizan la equivalencia y el intercambio cultural, en la práctica la participación en estoscircuitos tiende a reforzar las desigualdades existentes, tanto económicas como políticas.---This article offers a brief description of the cases of some women living in the region of Cusco, Peru, who are involved in the production or sale of ethnic objects for the tourist and the export markets. The analysis shows that, while social agents usually emphasize cultural equality and exchange in their discourse, in practice their participation in these circuits tends to reinforce economic and political inequalities.

  9. Unidades ambientales urbano-turísticas de Mar del Plata: apuntes para su identidad y caracterización

    OpenAIRE

    Dosso, Ricardo

    2001-01-01

    La identificación y caracterización de la vocación esencial en función turístico ambiental de áreas, sendas, hitos o núcleos componentes del escenario urbano turístico recreacional de centros urbanos permitirá codificar un sistema referencial de unidades susceptibles de puesta en valor de los recursos en el mercado de la oferta de atractivos, donde sus condiciones de identidad y carácter favorecerán su singularización en función de consolidar submarcas diferenciales, no obstante integrar una ...

  10. Dilemas y tensiones en torno al Trabajo Social en ciudad de La Plata en los primeros setenta

    OpenAIRE

    Arrúa, Néstor Nicolás

    2016-01-01

    En este trabajo buscaremos dar cuenta de los debates intelectuales y tensiones políticas en torno al Trabajo Social en los espacios de formación profesional de gestión pública en tiempos de una acelerada politización de sectores juveniles de las clases medias. Nos hemos circunscrito a los debates intelectuales en relación a los significados de la disciplina, en torno a los intentos de presentar una definición y moviliza fuerzas y tensiones en los distintos colectivos profesionales. Abordaremo...

  11. Prenatal lead exposure and relationship with maternal exposure determinants in a public maternity hospital of La Plata, Argentina.

    Science.gov (United States)

    Martins, Enrique; Varea, Ana; Apezteguía, María; González, Horacio F; Girardelli, Ana; Caro, Laura Sanchez; Lobisuto, Mario; Delgado, Griselda; Disalvo, Liliana

    2014-03-01

    Prenatal lead exposure is a health hazard that may cause cognitive development impairments and other adverse effects in children. We conducted a cross sectional study analyzing cord blood lead levels (CBLL) of newborns and their relationship with maternal determinants of lead exposure. Mothers answered a questionnaire about socio-demographic, lifestyle habits and environmental characteristics. We used Mann-Whitney's test to compare CBLL geometrical means (GM) corresponding to the presence or absence of each lead exposure determinant, and Chi square test to study the relationship between CBLL and maternal lead exposure determinants. A total of 159 newborns participated in the study. CBLL GM was 2.1 μg/dL; and 25% of the participants had a measurable CBLL (LOQ=3.3 μg/dl). Although the participants had several determinants of lead exposure, we only found a significant relationship with inside household determinants, such as presence of lead piping (p=0.026), unplastered walls (p=0.046) and peeling paint (p=0.048). Our results show that CBLL GM was similar to that reported in several studies conducted around the world. However, 25% of the participants might have some degree of risk for lead poisoning. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Estudio exploratorio de la oferta de bebidas sin alcohol en comercios mayoristas y minoristas de ciudad de La Plata

    OpenAIRE

    Papalardo, Brenda; García, Silvia; Prestes, Mariana; Fasano, María Victoria; Olmedo, Luciana; Henning, María Florencia; Malpeli, Agustina; Bisceglia, María Gabriela; Pellón Maisón, Magalí

    2017-01-01

    Los hábitos de consumo alimentario actuales promueven el sobrepeso y la obesidad. Se consiguen alimentos a menores precios, particularmente aquellos con una alta densidad energética y con mayor grado de procesamiento, como las bebidas endulzadas con edulcorantes calóricos. La Argentina se posiciona como uno de los líderes del mercado y como uno de los mayores consumidores a nivel mundial de este tipo de bebidas. Los objetivos de este trabajo fueron: -Explorar el contenido total de hidra...

  13. Police, anthropometry, and fingerprinting: the transnational history of identification systems from Rio de la Plata to Brazil.

    Science.gov (United States)

    Ferrari, Mercedes García; Galeano, Diego

    2016-12-01

    The article explores the transnational circulation of methods for identifying people in South America. It analyzes both the implementation of the anthropometric system at police departments in Argentina, Uruguay, and Brazil starting in the 1890s, as well as the criticisms that were aimed at this method when fingerprinting took hold in the region in the early twentieth century. In a context of a heavy worldwide flow of ideas, experts, and technologies in policing, "bertillonage" was discussed and underwent hybridization in Latin America. The history of the anthropometric system in these three countries involved many travels by physicians, jurists, and police agents to Paris, debates over its suitability to local contexts, and an open controversy about identification techniques.

  14. Ferromagnetism in manganite s substituted with silver of perovskite structure; Ferromagnetismo en manganitas sustituidas con plata de estructura perovskita

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, N.; Hernandez, T.; Dzul, I.; Pena, Y., E-mail: thernang@yahoo.co [Universidad Autonoma de Nuevo Leon, Facultad de Ciencias Quimicas, Laboratorio de Materiales I, Ciudad Universitaria, Av. Pedro de Alba s/n, 66450 San Nicolas de los Garza, Nuevo Leon (Mexico)

    2011-07-01

    A series of mixed oxides of general formula Sm{sub 1-x}Ag{sub x}MnO{sub 3} with perovskite structure were prepared by first by conventional solid-state reaction processing. The structure, morphology and magnetism of the samples are investigated. The X-ray diffraction patterns show that the x=0.1 sample is a single perovskite structure, while x{>=} 0.2, samples consist of a ferromagnetic perovskite phase and two nonmagnetic phases, Ag and Ag{sub 1.8}Mn{sub 8}O{sub 16}. The ferromagnetic behavior of Sm{sub 1-x}Ag{sub x}MnO{sub 3} decrease with increase of Ag composition. The Sem analysis when x=0.1 revealed that the random distribution of morphology and size of particles result of preparation method. The samples of Sm{sub 1-x}Ag{sub x}MnO{sub 3} by x between 0.1 and 0.5 show that applying 10 T fields these cannot reach a saturation value. (Author)

  15. Hurto, consumo y género en el servicio doméstico (Mar del Plata, 1950-1980

    Directory of Open Access Journals (Sweden)

    Inés Pérez

    2016-12-01

    Full Text Available Las ciencias sociales han discutido largamente sobre el papel del intercambio de bienes, valores culturales y pautas de consumo en el marco del servicio doméstico. En ese contexto, los hurtos de las trabajadoras domésticas a sus empleadores han sido leídos como parte de formas de resistencia hacia las desigualdades experimentadas en el marco de su trabajo. Retomando esos aportes, este artículo se centra en los objetos hurtados, muchas veces de escaso valor monetario pero de un alto valor simbólico, asociados a la feminidad. A partir del análisis de diecinueve expedientes de hurto, se sostiene que el hecho de que este tipo de objetos estuvieran involucrados de manera recurrente en casos de robo responde a una forma particular de definir la justicia, anclada en el acceso a ciertos bienes. La centralidad de estos bienes muestra, además, la circulación de distintos modelos de feminidad entre trabajadoras y empleadoras.

  16. El Río de la Plata a comienzos del siglo XVIII: estrategias y propuestas en tiempos de guerra

    OpenAIRE

    González Mezquita, María Luz

    2015-01-01

    El interés despertado por la Guerra de Sucesión Española y los procesos vinculados a ella en los últimos años, aunque muchos temas merecen aún investigaciones exhaustivas, ha mejorado su conocimiento a partir de los resultados de reuniones cient�

  17. Género, turismo y exportación: ¿llamando a la plata en el Perú?

    Directory of Open Access Journals (Sweden)

    Jane Henrici

    2007-12-01

    Full Text Available El siguiente artículo es una descripción breve del caso de algunas mujeres de la región de Cusco, en Perú, involucradas en la producción o en la venta de objetos étnicos para el mercado turístico y para la exportación. El análisis muestra que, mientras que en su discurso sobre el turismo y el comercio los actores enfatizan la equivalencia y el intercambio cultural, en la práctica la participación en estos circuitos tiende a reforzar las desigualdades existentes, tanto económicas como políticas.

  18. Cuatro miradas bibliotecarias desde el Río de la Plata = Four librarian views from River Plate

    Directory of Open Access Journals (Sweden)

    Alejandro E. Parada

    2000-12-01

    Full Text Available La primera mirada del autor identifica y enumera las publicaciones periódicas argentinas especializadas en Bibliotecología existentes en 2000, más la mención a algunas ya cesadas. En su análisis deja de lado los criterios de excelencia aplicables a la edición científica para echar una segunda mirada sobre la realidad bibliotecológica argentina, panorama localizado en un país con bajos niveles de desarrollo, donde las bibliotecas son pobres e insuficientes y carente de un potente sistema de información, es por eso que la aparición de un número importante de títulos de periódicas aporta entusiasmo y optimismo respecto de una realidad tan complicada. La tercera mirada enfoca en los ideales bibliotecarios argentinos y americanos, en la investigación bibliotecológica, en las nuevas orientaciones y en los paradigmas tanto existentes como los que desafiarán el statu quo. La cuarta mirada se centra en las virtudes de escribir sobre lo que se investiga, sobre lo que se hace en las bibliotecas y sobre lo que se espera porque ningún título podrá perdurar sin la contribución constante de los bibliotecólogos = The first look of the author identifies and lists the current Argentine specialized periodicals in in 2000, over the mention of some already ceased. In his analysis ignores the excellence criteria applicable to scientific publishing to take a second look at the reality of librarianship in Argentina, located in a developing country, where libraries are poor and insufficient and without a powerful information system, which is why the emergence of a number of periodical titles brings enthusiasm and optimism in front of a complicated reality. The third view focuses on the ideals Argentine and Latin American librarians, in the library research, and in new directions and paradigms in both existing and those who challenge the status quo. The fourth eye focuses on the virtues of writing about the research done, on what is done in the libraries labor, and what is expected, because no title will remain without the constant contribution of librarians.

  19. Avances en los métodos de recuperación de oro y plata de minerales refractarios

    OpenAIRE

    Parga, J. R.; Carrillo, F. R.

    1996-01-01

    Recent research work in hydrometallurgical processes for precious metals recovery from refractory ores is analyzed. Advantages and applications are discussed. Likewise, two methods, one stage direct pressure oxidation/cyanidation and pyrometallurgical recovery, are also described. In the first one, gold and silver oxidation and recovery can be carried out in the same reactor simultaneously. A higher than 96 % recovery in less than 90 min can be achieved. As for the pyrometallurgical recovery ...

  20. Commercial policies in frontier reductions: Models, reappropriations and disputes (Río de la Plata, 18th century

    Directory of Open Access Journals (Sweden)

    Lía Quarleri

    2018-01-01

    Full Text Available The aim of this paper is an analysis of the commercial policy implemented by the colonial bureaucracy on the Guarani Reductions, also the adaptations, responses and conflicts this process originated. The historical sources are analyzed from an anthropological perspective. First, the colonial commercial policies applied on the Guarani missions are put in context. Second, the controversies within the colonial administration are interpreted. Finally, indications of indigenous participation in this trade is described. The bias found in the official documents is a limitation of this study. Its value, however, lies in an analysis which brings together regulations, conflicts and indigenous agency. It is concluded that the political mediation designed to hinder the missionary population’s free access to the new commercial system had the opposite effect.

  1. ICON - 2015 Meteorological and Oceanographic Observations: Puerto Plata, Catuan Wreck, Little Cayman, Angel's Reef, and Port Everglades (NCEI Accession 0156578)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Atlantic Oceanographic and Meteorological Laboratory (AOML) of OAR is conducting research on the influence of meteorological and oceanographic factors upon coral...

  2. Geologic characterization of paleoproterozoics rocks in middle south of Uruguay (PIEDRA ALTA terrains - Craton of Rio de la Plata)

    International Nuclear Information System (INIS)

    Oyhantcabal, P.; Spoturno, J.; Loureiro, J.

    2007-01-01

    An updated synthesis of the Units of the Precambrian Basement (Piedra Alta Terrane; Paleoproterozoic; Transamazonian Cycle) of Montevideo, Canelones, San Jose and southern Florida is presented. This review is based on data from a mapping project (CONICYT 6019) of the area at 1:100 000 scale. Two metamorphic successions are recognised in the San Jose Belt: Paso Severino and Montevideo formations (low and medium grade respectively) and an significant bimodal magmatism recorded in syn- as well as postoregenic intrusions. A system of conjugated shear zones (ENE and NNW; sinistral and dextral respectively) determine the architecture of the Basement. (author)

  3. Patos Lagoon Outflow Within the Rio de la Plata Plume Using an Airborne Salinity Mapper: Observing an Embedded Plume

    Science.gov (United States)

    2008-01-01

    19 February 2004. Meteorological observations were also re- depths of several meters. In spite of the apparent inaccuracy, we corded manually from the...Brigada de Mantenimiento , Servicio Application of data from near-coincident airborne and in-situ de Sensores Remotos y Aeroespaciales, and Escuadr6n

  4. Base de datos estadísticos de las bibliotecas de la Universidad Nacional de La Plata : una experiencia cooperativa

    OpenAIRE

    Fushimi, Marcela-S; Pichinini, Mariana; Archuby, Gustavo; Mangiaterra, Norma

    2008-01-01

    In October 2001, there were formed the Interlibraries Task Forces (ITF) in the field of libraries of the UNLP with the idea of moving in various joint projects and form a network, whose face visible is Portal ROBLE (www.roble.unlp.edu.ar). Among the teams, the ITF Evaluation of Information Units, was established with the aim of developing "management indicators applicable to all libraries of the UNLP in order to measure and diagnose them, facilitating decision making and processes of co...

  5. Surgimiento, dinámica y rol de las plantineras en el aglomerado hortícola de La Plata

    Directory of Open Access Journals (Sweden)

    Matías García

    2016-12-01

    Full Text Available RESUMEN La caracterización de la actual dinámica del Cinturón Hortícola Platense tendría un mejor ajuste si se interpreta desde el enfoque de economías de aglomeración. Así, una actividad que se caracterizó históricamente por su producción atomizada y descentralizada, ahora muestra una concentración espacial y cercana articulación con los eslabones de aprovisionamiento de insumos y comercialización. El objetivo del trabajo es desarrollar la influencia y dependencia de un servicio existente en la zona hortícola platense: las plantineras. Se busca identificar las razones de su surgimiento, su evolución y actual importancia y dependencia. También describir su interrelación con las semilleras y agronomías. Finalmente, se caracteriza el rol de las plantineras en el aglomerado de empresas que conforma la horticultura platense. Se concluye que las plantineras pueden considerarse un caso de economía externa, causa y consecuencia a su vez del incremento de la competitividad en este espacio productivo. ABSTRACT The current dynamics of La Plata’s Horticultural Belt seem to fit better if interpreted from the agglomeration economies perspective. Thus, an activity historically characterized by its fragmented and decentralized production nowadays shows a spatial concentration and close coordination with the links in supply of inputs and marketing. The aim of this work is to develop the influence and dependence on an existing service in La Plata’s horticultural zone: the nursery garden. It seeks to identify the reasons for its emergence, evolution and current importance and dependence. Also to describe their interrelationships with seed companies and agrochemical shops. Finally, the nursery garden role in horticultural agglomerate of La Platais characterized. It is concluded that nursery garden could be considered a case of external economy, cause and consequence of increasing competitiveness in the productive space.

  6. Calixarene receptors in the selective separation of alachlor. Characterization of the separated complexes; Receptores calixarenicos en la separacion selectiva de alaclor. Caracterizacion de los complejos separados

    Energy Technology Data Exchange (ETDEWEB)

    Garcia G, M C

    2004-07-01

    Pesticides have been necessary in the agriculture since the plagues control have been remedied thanks to them but it has also provoked pollution. Nowadays, there are several methods which help to decrease or remedy such a pollution provoked. Unfortunately, any of them work out the environmental problem totally. Therefore, alternatives have to be found. The organic and tri dimensional characteristics of these macrocycles afford them a high versatility in such a way that these hosts can interact with organic guests selectively. Alachlor is a chlorinated organic herbicide useful in the plagues control of annual grasses and many broad-leave weeds which grow in maize, peanuts and soyabean. The ability of calixarenes to host organic guests with chemical characteristics similar to pesticides let them to be good candidates to compete with others methods which are used presently to separate organic pesticides. In this direction one of the advantages of proposing the use of calixarenes is, its facility of being modified in the lower and/or upper rims, to adapt them to aqueous, organic, gaseous and aqueous-organic media. Once the characteristics of reagents informed in the literature were confirmed and complemented with others found in this work, we studied, in solution, the interaction of the calixarenes with alachlor using 1 x 10{sup -5} to 1 x 10{sup -3} M solutions in acetonitrile for calixarenes fitted with phosphinoyl pendant arms in the lower rim, B{sub n}bL{sup n}, n= 4, 6) and in chloroform for parents calixarenes (H{sub n}bL{sup n} n = 4, 6, 8). Meticulous studies monitored by UV-Vis and luminescence were carried out, and the best stoichiometry to be used in further studies resulted to be 1(host): 1(alachlor). Therefore, we chose the 1 x 10{sup -4} M concentration to find how long the host-guest should be interacting in order to guarantee the formation in solution of the calixarene-alachlor species. It was found 168 h for the alachlor-B{sub n}bL{sup n} interaction while 165 h were necessary with H{sub n}bL{sup n} in dilute as concentrate solutions, solvents as chloroform and acetonitrile did not interfere in the formation of the species. At the same time and based on the structure of the reactants and information from the scientific literature related to this particular topic, using the M M3, CONFLEX and MOPAC/PM5/COSMO procedures, we calculated the optimized geometry which rendered the most stable molecular structures of reactants and products, this means those with the lowest minimum energies, the lowest energies of the most stable conformers and the heat of formation of the most stable conformational structures of the calixarene-substrate species. The latter were those formed by hydrogen bonding and {pi}-{pi} interactions. Species formed with H{sub n}bL{sup n} stabilized by hydrogen bonding through CH{sub 2}-Cl interaction of alachlor with OH groups of the calixarenes. Concerning the phosphinoylated calixarenes, the P=O groups immobilize the alachlor by hydrogen bonding with the benzyl of the acetanilide. However, the species formed with alachlor and parents or functionalized calixarenes demanded a second interaction between calixarene phenyl-{pi}-{pi}-benzyl-alachlor to be stabilised. Heat of formation of reactants and products allowed to calculate the heat o reaction associated to the formation of the hosts...guest species, these results were surprising in line with the experimental results. Based on the solution and computational results we synthesized and isolated the calixarene---alachlor complexes in sizeable amounts. The latter were characterized by spectroscopic techniques like IR, UV-Vis, luminescence and elemental analysis. The results from the solution and solid studies of the reagents and products as molar absorption coefficients, the features of the luminescence and IR spectra, luminescence lifetimes and minimum formulae of the isolated complexes are in good agreement with the parameters and tendencies of the minimum energies of the geometrical and conformational structures found. With respect to the separation of alachlor of aqueous medium studies, the found results are noteworthy since they indicate that the studied calixarenes could be useful for water treatment in a future, taking into account that the treatment of real wastewater imply. Under our experimental conditions, the distribution coefficients were found to be between 0.89 - 1.06 for H{sub n}bL{sup n} (in chloroform) and with B{sub n}bL{sup n}, between 0.23 - 0.96. In general we propose that the pH control could be important in the separation of alachlor with phosphinoylated pt-butylcalix [4, 6]arenes in order to get reproducibility of the results but it is not necessary for parents pt-butylcalix [4, 6, 8]arenes. The B{sub 4}bL{sup 4} requires pH control to manage a extraction up to 81 % but the B{sub 6}bL{sup 6} did not, because it extracts 95 % to the pH of deionised water. However, at pH =3, B{sub 4}bL{sup 4} extracts 92 % of alachlor while B{sub 6}bL{sup 6} extracts only 23 %, this was interpreted as a good selectivity of B{sub 4}bL{sup 4} for the alachlor. In the case of the parents calixarenes, the H{sub 4}bL{sup 4} shows larger extraction capability towards the alachlor. (Author)

  7. CARACTERIZACION FENOTIPICA Y TIPIFICACION MOLECULAR DE CEPAS DE CRYPTOCOCCUS NEOFORMANS AISLADAS DE MUESTRAS CLINICAS EN HOSPITALES TERCIARIOS DEL SUR DE CHILE

    OpenAIRE

    BARRIA I., YOLANDA B.

    2012-01-01

    Criptococosis es una micosis sistémica oportunista causada por dos especies levaduriformes capsuladas, C. neoformans causan infecciones en individuos immunodeprimidos ptincipalmente y Criptococcus gattii lo hace tanto en immunocompetentes como en personas inmunodeprimidas. C. neoformans es comúnmente asociado a excretas de palomas mientras que la especie C. gattii es encontrado en especies arbóreas como eucaliptos, ficus y otras. C neoformcms se subdivide en dos variedades distintas neofor...

  8. Preparation and characterization of alpha sources as standards in the actinides separation; Preparacion y caracterizacion de fuentes alfa como estandares en la separacion de actinidos

    Energy Technology Data Exchange (ETDEWEB)

    Monroy G, F.; Escobar A, L.; Zepeda R, C. P.; Balcazar, M., E-mail: fabiola.monroy@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2017-09-15

    The radioisotopes Am-243, Cm-244, Pu-242 and U-232 are used as radioactive tracers in the processes of separation and quantification of the radioisotopes of Am, Cm, Pu and U contained in radioactive and nuclear wastes, with the purpose of determining the efficiency of said processes. For this, in this work, alpha sources of Am-243, Cm-244, Pu-242 and U-232 standards were prepared by two methods: evaporation and electro-deposition, and they were analyzed by means of alpha spectrometry to verify the properties of these radioactive standards. The alpha sources prepared by electro-deposition were analyzed by Raman spectrometry to determine the chemical form in which the actinide was deposited; the good homogeneity in the distribution of the deposit was determined with solid nuclear trace detectors. The resolution of the alpha spectra obtained with surface barrier detectors of the standards is greater when deposited by electro-deposition. The FWHM of the alpha sources prepared by electro-deposition is always lower than that prepared by evaporation. Actinides are electrodeposited in the form of hydroxides and oxo compounds. (Author)

  9. Application of the techniques of Multivariate analysis in the characterization of germplasm of Quinua; Aplicacion de tecnicas de Analisis multivariado en la caracterizacion de germoplasma de Quinua

    Energy Technology Data Exchange (ETDEWEB)

    Garcia A, J.M.; Torres de la Cruz, E. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: jmga@nuclear.inin.mx

    2004-07-01

    Its were evaluated 20 lines of Chenopodium quinoa respect characters of agronomical interest finding that nine lines overcame the witness highlighting the lines: 20R1-41, 20R1-10, 20R2-27 that presented near yield to 1.5 ton/ha. The multivariate analysis of main components generated a dendrogram in that is appreciated that at an Euclidean distance of 0.75 its were formed seven groups according to its morphological characteristics and of yield, it highlights the formation of two big groups at a distance of 1.125, that they separate according to the radiation dose (200 and 250 Gy). (Author)

  10. Investigations on the nature and physical concentration of Spanish uraniferous quartzites; Estudios de caracterizacion y concentracion fisica de cuarcitas uraniferas espanolas

    Energy Technology Data Exchange (ETDEWEB)

    Lora, F de [Direccion de Plantas Piloto e Industriales, Junta de Energia Nuclear, Madrid (Spain)

    1967-06-15

    A study was made of a sample of radioactive material from Santa Elena (Jaen) containing 130 ppm U{sub 3}O{sub 8}, 300 ppm ThO{sub 2}, 4.96% ZrO{sub 2} and 14.29% TiO{sub 2}. Over 150 million tons of material were examined. In the light of the studies carried out the material can be defined as a rutilo-zirconiferous quartzite with a double radioactivity source due to the uranium enclosed in the zircon lattice structure and to the presence of monazite. The possibility of brannerite or davidite being present can be discarded. There is likewise no conclusive evidence of the presence of sphene, rutile being the most abundant titanium mineral. The author determined the features of the ore with a view to its physical concentration and applied magnetic and gravimetric separation and the flotation process. The use of oleic acid as collector has permitted good zircon recovery. (author) [Spanish] Se ha estudiado una muestra de material radiactivo procedente de Santa Elena (Jaen) con 130 ppm de U{sub 3}O{sub 8}, 600 ppm de ThO{sub 2}, 4,96% de ZrO{sub 2} y 14,29% de TiO{sub 2}. El material examinado es considerable: mas de 150 millones de toneladas. De acuerdo con los estudios realizados se puede definir como una cuarcita rutilo-circonifera con dos fuentes de radiactividad debidas al uranio englobado en la red del circon y a la presencia de monacita. Se descarta la posibilidad de existencia de brannerita o davidita. Tampoco existen pruebas concluyentes de que contenga esfena, siendo el ratilo el mineral de titanio mas abundante. Se han determinado las caracteristicas de la mena con vistas a su concentracion fisica. Se ha ensayado la separacion magnetica, gravimetrica y flotacion. El empleo de acido oleico, como colector, ha dado buenas recuperaciones de circon. (author)

  11. Characterization of tuna cooking effluents generated in seafood canning industries; Caracterizacion de los efluentes de coccion de atum generados en la industrias conserveras de productos marinos

    Energy Technology Data Exchange (ETDEWEB)

    Mendez Paz, D.; Torres Ayaso, A. B.; Vieites Baptista de Sousa, J. M.

    2006-07-01

    Tuna cooking effluents from different factories were analyzed, in this work. It has been analyzed effluents form water cooking and steam cooking processes. Steam cooking effluents are more appropriate for protein recovery due to the higher protein concentrations (up to 10 g/l, in some cases) and lower volume. Besides, steam cooking effluents, chemical oxygen demand (COD) and total Kjeldahl nitrogen (TKN) were up to 50 and 5 g/l, respectively. Different correlations between the main parameters the main parameters have been found, for example protein and TKN concentrations of a tuna cooking effluent can be estimated from COD concentrations. (Author) 9 refs.

  12. CARACTERIZACION DE LA PROTEINA QUINASA CK2 EN ARABIDOPSIS THALIANA Y SU PAPEL EN LA RESPUESTA DE DEFENSA A ESTRES OXIDATIVO.

    OpenAIRE

    SALINAS SALVO, PAULA ANDREA; SALINAS SALVO, PAULA ANDREA

    2006-01-01

    CK2 es una proteína quinasa heterotetramérica compuesta de dos subunidades catalíticas a y dos subunidades reguladoras P. CK2 es esencial, esta presente en todos los organismos eucariontes y regula una gran cantidad de procesos celulares como por ejemplo 180p.

  13. Preparation and structural characterization of the thermoluminescent material CaSO{sub 4}: Dy; Preparacion y caracterizacion estructural del material termoluminiscente CaSO{sub 4}: Dy

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez R, A.; Azorin, J. [UAM-I, 09340 Mexico D.F. (Mexico); Gonzalez M, P.R. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Rivera, T. [CICATA-IPN, Legaria 694, 11500 Mexico D.F. (Mexico)

    2005-07-01

    The grade of crystallinity of a material is important so that the one is presented the thermoluminescence phenomenon; for what is necessary to study those structural characteristic of a TL material and to correlate them with its TL response when being irradiated with ionizing radiation. The calcium sulfate activated with Dysprosium (CaSO{sub 4}: Dy) it is a material that has demonstrated its efficiency in the dosimetry of the ionizing radiation for the thermoluminescence method. In this work the structural characterization of this prepared material for the recrystallization method by means of the evaporation of the solvent and their relationship with their TL response is presented. The results showed that the best material to be used in thermoluminescent dosimetry presents a crystalline structure in orthorhombic phase and a particle size in the interval of 80 {mu}m to 200 {mu}m. (Author)

  14. Characterization of agua de Ramon marbles, Cordoba Province, Argentina; Caracterizacion de los marmoles de agua de Ramon Provincia de Cordoba, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Tourn, S; Castro, L. [Departamento de Ciencias Geologicas, Facultad de Ciencias Exactas y Naturales, Universidad de buenos Aires, (Argentina)]. E mail: selvia@fcen.uba.ar, lilianacastro@fibertel.com.ar

    2004-09-01

    Agua de Ramon district is located in the NW of Cordoba, Argentina, between 3 49' and 30{sup 0}52' S and 65{sup 0}21' and 65{sup 0}24' W, in the Eastern Pampean Range setting. It was a very important tungsten district until the end of 1950'decade when tungsten mining became of no economic interest. The objective is to report for the first time the petrological, mineralogical and geochemical characteristics of several marble lenses located in the sourthern of the area. Marble outcrops are lenticular ranging from 1 m to 80 m in length and 0.50 m to 20 m width. They appear massive, fine-grained and in light colors (white, pale green, very light brown and pale gray). These last varieties show a distinct banded structure due to little differences in color. These marbles are mainly composed of magnesian calcite accompanied by minor amounts of dolomite, forsterite, humite group minerals, tremolite, talc, serpentine and clinochlore, and scheelite, sphene, apatite and opaque minerals like hematite, magnetite, illmenite, pirrothite and pyrite as accessory minerals. Major chemical analyses indicate a relatively high SiO2 and MgO content, and minor CaO, in comparison with marbles of this type. Mineral paragenesis was useful to evaluate metamorphism conditions in this area. [Spanish] El distrito Agua de Ramon se localiza en el departamento de Minas al noroeste de la provincia de Cordoba, Argentina, entre los paralelos 30{sup 0}49' y 30{sup 0}52' de latitud sur y los meridianos 65{sup 0}21' y 65{sup 0}24' de longitud oeste, en el ambito de las Sierras Pampeanas Orientales. En el pasado constituyo un importante distrito de explotacion wolframifera, pero dicha actividad se halla paralizada desde fines de la decada del '50. El objetivo de este trabajo es hacer conocer por primera vez las caracteristicas de los marmoles localizados en el sector sur desde el punto de vista petrografico, mineralogico y geoquimico de manera que permita realizar un analisis petrogenetico. Los cuerpos son de formas lenticulares, con potencias y longitudes variables (0.50 m a 20 m y 1 m a 80 m). Los marmoles son de color blanco y estructura maciza o bien en tonalidades verdosas, castanas y grises, dando paso a una estructura bandeada no marcada; la textura es de grano fino a mediano. Su composicion es esencialmente calcitica con contenidos de magnesio elevados en relacion con su mineralogia, que consiste en calcita, dolomita, forsterita, grupo de la humita, tremolita, talco, serpentina y clinocloro. Los accesorios son scheelita, titanita, apatita y minerales opacos como magnetita, ilmenita, hematita, pirrotina y pirita. Los analisis quimicos mayoritarios indican contenidos relativamente elevados de SiO2 y MgO y menores de CaO en comparacion con valores de la literatura. La paragenesis registrada en estos marmoles permitio evaluar las condiciones de metamorfismo imperantes en el area.

  15. The study of cultural objects by nuclear and conventional techniques; Estudio de bienes culturales con tecnicas de caracterizacion nucleares y convencionales

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, Tulio A [Comision Nacional de Energia Atomica, General San Martin (Argentina). Centro Atomico Constituyentes

    2000-07-01

    A survey is given of the techniques that are used at the National Atomic Energy Commission of Argentina for the characterization and study of cultural and archaeological specimens. A short history of these activities is also given. (author)

  16. Synthesis, characterization and application of calcium oxides for the adsorption of carbon dioxide; Sintesis, caracterizacion y aplicacion de oxidos de calcio para la adsorcion de dioxido de carbono

    Energy Technology Data Exchange (ETDEWEB)

    Granados P, A.

    2016-07-01

    In this research, calcium oxide (Ca O), nanocrystalline calcium oxide and their Fe and Ni nano composites were synthesized by solution combustion and high-energy ball-milling processes respectively, in order to study their CO{sub 2} adsorption behavior under different pressure and temperature conditions. The obtained materials were characterized by different analytical techniques: XRD, Sem-EDS and N{sub 2} physisorption measurements. CO{sub 2} adsorption experiments on adsorbents at different temperatures and pressures, were carried in a stainless steel Parr type high vacuum reactor. The CO{sub 2} adsorbed on the materials was determined by thermogravimetric analysis and mass spectrophotometry. The results showed that the synthesis methods, solution combustion and high energy ball milling allowed to improve the materials textural and structural properties such as specific surface area, total pore volume, pore size distribution and nano crystallinity, which played an important effect on the CO{sub 2} adsorption behavior. It was found that the Ca O obtained by solution combustion and milled during 2.5 h, showed the maximum CO{sub 2} adsorption capacity per gram of material (9.311 mmol/g) at ambient temperature and pressure, by chemisorption as adsorption mechanism, due CaCO{sub 3} formation, which was confirmed by infrared spectroscopy, X-ray diffraction and X photoelectron spectroscopy studies. In general, the investigation results show the potential benefits of these materials efficient use, based on Ca O obtained by solution combustion and treated by high-energy ball milling, as well as that will mitigate environmental problems posed by global warming and reduce the negative impacts to the environment and living beings. (Author)

  17. Liquid radioactive wastes characterizing obtained of {sup 99} Mo production by fission; Caracterizacion de residuos liquidos radiactivos provenientes de la produccion de {sup 99} Mo por fision

    Energy Technology Data Exchange (ETDEWEB)

    Devida, Claudio; Bouza, Edgardo; Gil, Daniel; Neuringer, Silvia [Comision Nacional de Energia Atomica, Buenso Aires (Argentina). Centro Atomico Ezeiza. Unidad de Actividad Materiales y Combustibles Nucleares; Ramallo, Telma [Comision Nacional de Energia Atomica, Buenos Aires (Argentina). Centro Atomico Ezeiza. Unidad de Actividad gestion de Residuos Radiactivos

    1999-11-01

    Among its facilities, the National Atomic Energy Commission of Argentina has a {sup 99} Mo by Fission Production Plant, which generates, among others, low and medium activity liquid waste. The characterization of the waste aims at obtaining the array of data that is necessary to carry out the processed which lead to obtain an acceptable product for its storage and final disposal. The Analytical Chemistry Laboratory faced the development, adjustment and execution of the necessary analytical procedures to achieve the physico-chemical characterization of the main liquid waste. Given the complexity and activity of the waste, high sensitivity instrumental analytical techniques were chose and the equipment was adapted to work in radiochemical hoods. In a first stage, simulated solutions were used in order to adjust the methods and techniques and to carry out studies about interference and results statistics. Afterwards, physico-chemical analysis were performed on real waste samples yielding satisfactory results as regards precision required for this kind of waste. (author) 6 refs., 4 figs., 5 tabs.

  18. Characterization of contaminated soils using a x-ray fluorescence equipment; Caracterizacion de suelos contaminados mediante un equipo portatil de fluorescencia de rayos X

    Energy Technology Data Exchange (ETDEWEB)

    Quindos, L. S.; Fuente, I.; Sainz, C.; Queral, I.

    2006-07-01

    Fast and accurate material identification is required in many areas of the metal industry as well as surveillance of contaminated areas. The portable X-ray analyzer described in this paper consists of a hand-held probe and electronic unit. The system is configured with three excitation sources, such as ''241 Am, ''109Cd and ''55 Fe, which provides excellent performance for common elements to be controlled in contaminated soils. Data about measurements developed with this device in field as well as in the laboratory are shown in this paper. (Author)

  19. Synthesis and structural characterization of amorphous alloys of the Fe-Ni-B type; Sintesis y caracterizacion estructural de aleaciones amorfas del tipo Fe-Ni-B

    Energy Technology Data Exchange (ETDEWEB)

    Cabral P, A.; Jimenez B, J.; Garcia S, I. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)

    2004-07-01

    It was prepared the alloy FeNiB for chemical reduction, using four p H values (5, 6, 7 and 7.5). To p H=6 partially oxidized particles were obtained, between 16 and 20%. In the synthesis to other p H values, the obtained particles were highly oxidized (65-90%) according to the X-ray diffraction results, in all the preparations the particles were partially crystallized, with crystal size that varied between 4 and 10 nm. The structure of these particles can be consider that they are formed by a nucleus due to the alloy and an oxide armor recovering it. (Author)

  20. Synthesis and characterization of nanoparticles of nickel obtained by laser ablation; Sintesis y caracterizacion de nanoparticulas de niquel obtenidas por ablacion laser

    Energy Technology Data Exchange (ETDEWEB)

    Aviles, R.; Escobar A, L.; Camps, E.; Santiago, P. [ININ, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Ascencio, J.A.; Von, H. [Instituto Mexicano del Petroleo, Mexico D.F. (Mexico)

    2002-07-01

    The result of the formation of nickel nanoparticles by the laser ablation technique with a size less or equal to 1.3 nm is reported, also the formation of agglomerates of tens of nanometers is shown. Under the experimental conditions used a high particle density (around 10{sup 5} particles/{mu}m{sup 2}) is obtained. The stability of the particles in function of its atom quantity, for less or equal sizes to 2 nm is studied, finding that the most stable structure is the icosahedron. (Author)