Distribución geográfica, historia natural y conservación del hurón menor Galictis cuja (Carnivora: Mustelidae en la Patagonia central, Argentina Geographic distribution, natural history and conservation of the lesser grison Galictis cuja (Carnivora: Mustelidae from Central Patagonia, Argentina

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Marcelo Carrera

2012-12-01

Full Text Available El hurón menor, Galictis cuja, tiene una amplia distribución en el territorio patagónico extraandino, aunque sus registros puntuales son escasos. Este trabajo se desarrolló en la provincia del Chubut, Patagonia Central, Argentina. Aquí se aportan nuevas localidades de registro de G. cuja para esta región; se discuten aspectos de su distribución geográfica y conservación en el Área Natural Protegida Península Valdés (ANP-PV; Patrimonio Natural de la Humanidad y brevemente se explora la representación de G. cuja en los ensambles de carnívoros del ANP-PV desde el Holoceno tardío hasta la actualidad. Se adicionaron 18 nuevos registros de G. cuja en Patagonia central. Se detectó un conflicto entre los pobladores y hurones, que motiva la caza de estos últimos. Se verificó un aparente incremento de abundancia de G. cuja en los últimos miles de años, concomitante con la extinción regional o dramática disminución de Lyncodon patagonicus (Carnivora, Mustelidae.The Lesser Grison, Galictis cuja, is a species widely distributed in extra-Andean Patagonia, although its records are scarce. This work was carried out in Chubut province, Central Patagonia, Argentina. Here we report new occurrence localities of G. cuja for this region; we discuss aspects of their geographical distribution and conservation in the Área Natural Protegida Península Valdés (ANP-PV; World Heritage Site and briefly explores the representation of G. cuja in carnivore assemblages of ANP-PV, since the late Holocene to the present. We added 18 new records of G. cuja in Central Patagonia. We detected a conflict between the rural residents and the Lesser Grison, which motivates the hunting of the latter. There was an apparent increase in abundance of G. cuja in the last thousands of years, concomitant with regional extinction or dramatic reduction of Lyncodon patagonicus (Carnivora, Mustelidae.

Sexual dimorphism in the mandible of the armadillo Chaetophractus villosus (Desmarest, 1804) (Dasypodidae) from northern Patagonia, Argentina

OpenAIRE

Squarcia, SM.; Sidorkewicj, NS.; Camina, R.; Casanave, EB.

2009-01-01

The aim of this study was to study the sexual dimorphism in adult Chaetophractus villosus (Desmarest, 1804), from northern Patagonia, Argentina. Eight mandibular traits were measured in 37 males and 34 females. Univariate and multivariate morphometric analysis were applied to the data set. Results showed that C. villosus was sexually dimorphic, with higher absolute values corresponding to females. The total length of the mandible was the most important variable to discriminate sexes, followed...

Polen de las Mieles de la Patagonia Andina (Chubut-Argentina Pollen of honeys from the Andean Patagonia (Chubut-Argentina

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Alicia Forcone

2006-07-01

Full Text Available Se describen e ilustran mediante fotomicrografías tomadas con MO y MEB, 30 tipos polínicos, determinados en las mieles producidas en la región andina de Chubut (Patagonia Argentina. Los tipos morfológicos descriptos pertenecen a las siguientes familias: Alstroemeriaceae, Apiaceae, Buddlejaceae, Caryophyllaceae, Caprifoliaceae, Celastraceae, Clusiaceae, Convolvulaceae, Ericaceae, Elaeocarpaceae, Fabaceae, Fagaceae, Lamiaceae, Papaveraceae, Polemoniaceae, Polygalaceae, Proteaceae, Ranunculaceae, Rosaceae, Saxifragaceae, Solanaceae, Thymelaceae y Verbenaceae. La mayoría de los tipos polínicos descriptos fueron hallados en las mieles como polen de menor importancia o traza con excepción de Aristotelia chilensis y Escallonia sp., que alcanzaron la categoría de polen dominante, y de Lomatia hirsuta, hallada como polen secundario.Thirty pollen types identified in the honeys from the Andean region of Chubut are described and illustrated by means of LM and SEM photomicrographs. Pollen types belong to the following families: Alstroemeriaceae, Apiaceae, Buddlejaceae, Caryophyllaceae, Caprifoliaceae, Celastraceae, Clusiaceae, Convolvulaceae, Ericaceae, Elaeocarpaceae, Fabaceae, Fagaceae, Lamiaceae, Papaveraceae, Polemoniaceae, Polygalaceae, Proteaceae, Ranunculaceae, Rosaceae, Saxifragaceae, Solanaceae, Thymelaceae, and Verbenaceae. Most pollen types described were found in the honeys as minor important pollen or traces, except Aristotelia chilensis, Escallonia sp., which reached the category of dominant pollen, and Lomatia hirsuta, which was found as secondary pollen.

A new species of Parapsectrocladius Cranston (Diptera: Chironomidae: Orthocladiinae) from Patagonia, Argentina.

Science.gov (United States)

Donato, Mariano; Mauad, Melina; Fuentes, María Cecilia

2015-01-21

Parapsectrocladius setosus sp. n. is described and figured as pupa and male imago, based on material collected in Patagonia, Argentina. The male of the new species groups with P. escondido Cranston & Añón Suárez by having the anal point tapering triangular; inferior volsella simple, rounded, without any dorsal ridge and apically blunt. It can be distinguished from P. escondido by the possession of strong setae on the inner margin of inferior volsella. New material of Parapsectrocladius belonging from several localities allows us to emend the generic diagnosis of the adult male, female and larva of Parapsectrocladius, discuss its phylogenetic position and to expand the geographic distribution of P. acuminatus Cranston, P. escondido and P. reissi. Cranston. 

A Gigantic, Exceptionally Complete Titanosaurian Sauropod Dinosaur from Southern Patagonia, Argentina

Science.gov (United States)

Lacovara, Kenneth J.; Lamanna, Matthew C.; Ibiricu, Lucio M.; Poole, Jason C.; Schroeter, Elena R.; Ullmann, Paul V.; Voegele, Kristyn K.; Boles, Zachary M.; Carter, Aja M.; Fowler, Emma K.; Egerton, Victoria M.; Moyer, Alison E.; Coughenour, Christopher L.; Schein, Jason P.; Harris, Jerald D.; Martínez, Rubén D.; Novas, Fernando E.

2014-01-01

Titanosaurian sauropod dinosaurs were the most diverse and abundant large-bodied herbivores in the southern continents during the final 30 million years of the Mesozoic Era. Several titanosaur species are regarded as the most massive land-living animals yet discovered; nevertheless, nearly all of these giant titanosaurs are known only from very incomplete fossils, hindering a detailed understanding of their anatomy. Here we describe a new and gigantic titanosaur, Dreadnoughtus schrani, from Upper Cretaceous sediments in southern Patagonia, Argentina. Represented by approximately 70% of the postcranial skeleton, plus craniodental remains, Dreadnoughtus is the most complete giant titanosaur yet discovered, and provides new insight into the morphology and evolutionary history of these colossal animals. Furthermore, despite its estimated mass of about 59.3 metric tons, the bone histology of the Dreadnoughtus type specimen reveals that this individual was still growing at the time of death. PMID:25186586

Root proliferation in native perennial grasses of arid Patagonia, Argentina

Institute of Scientific and Technical Information of China (English)

Yanina A. TORRES; Mara M. MUJICA; Sandra S. BAIONI; Jos ENTO; Mara N. FIORETTI; Guillermo TUCAT; Carlos A. BUSSO; Oscar A. MONTENEGRO; Leticia ITHURRART; Hugo D. GIORGETTI; Gustavo RODRGUEZ; Diego BENTIVEGNA; Roberto E. BREVEDAN; Osvaldo A. FERNNDEZ

2014-01-01

Pappophorum vaginatum is the most abundant C4 perennial grass desirable to livestock in rangelands of northeastern Patagonia, Argentina. We hypothesized that (1) defoliation reduce net primary productivity, and root length density and weight in the native species, and (2) root net primary productivity, and root length density and weight, are greater in P. vaginatum than in the other, less desirable, native species (i.e., Aristida spegazzinii, A. subulata and Sporobolus cryptandrus). Plants of all species were either exposed or not to a severe defoliation twice a year during two growing seasons. Root proliferation was measured using the cylinder method. Cylindrical, iron structures, wrapped up using nylon mesh, were buried diagonally from the periphery to the center on individual plants. These structures, initially filled with soil without any organic residue, were dug up from the soil on 25 April 2008, after two successive defoliations in mid-spring 2007. During the second growing season (2008-2009), cylinders were destructively harvested on 4 April 2009, after one or two defoliations in mid-and/or late-spring, respectively. Roots grown into the cylinders were obtained after washing the soil manually. Defoliation during two successive years did reduce the study variables only after plants of all species were defoliated twice, which supported the first hypothesis. The greater root net primary productivity, root length den-sity and weight in P. vaginatum than in the other native species, in support of the second hypothesis, could help to explain its greater abundance in rangelands of Argentina.

Insectos acuáticos de la Meseta del Somuncura, Patagonia, Argentina. Inventario preliminar

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Javier MUZÓN

2005-01-01

Full Text Available Se brinda un inventario preliminar de los insectos acuáticos de la Meseta del Somuncura y su área de influencia (Patagonia, Argentina realizado sobre la base de colecciones y registros previos de especies pertenecientes a los órdenes Ephemeroptera, Odonata, Hemiptera (Heteroptera, Trichoptera, Diptera (familias Ceratopogonidae, Culicidae y Psychodidae y Coleoptera. Se han relevado diversos tipos de ambientes en 14 localidades. El número de especies registrado asciende a 78, agrupadas en 51 géneros y 26 familias, de las cuales 33 se citan por primera vez del área. De los taxa registrados 83% de los géneros corresponden a grupos de amplia distribución (neotropicales, americanos o cosmopolitas, mientras que 41% de las especies presentan una distribución patagónica o andina.

Plan de comercialización Heliraid Patagonia

OpenAIRE

Mella, Natalia

2012-01-01

La Patagonia Argentina Austral, es considerada un icono a nivel mundial, reúne un conjunto de provincias y aspectos naturales únicos en el mundo1. La Cordillera de los Antes, sus paisajes, su geografía, y su historia. Muchos han sido los aventureros que dieron su vida por explorar y conocer esta zona. Y no todos vivieron para contarlo. Tradicionalmente, la Patagonia se caracterizaba por un escaso desarrollo comercial a raíz de los altos costos y su inaccesibilidad geográfica. Hoy, el desarrol...

APOROCOTYLE MARIACHRISTINAE N. SP., AND A. YMAKARA VILLALBA & FERNANDEZ, 1986 (DIGENEA: APOROCOTYLIDAE) OF THE PINK CUSK-EEL, GENYPTERUS BLACODES (OPHIDIIFORMES: OPHIDIIDAE) FROM PATAGONIA, ARGENTINA

Czech Academy of Sciences Publication Activity Database

Hernandez-Orts, J.S.; Alama-Bermejo, Gema; Carillo, J.M.; García, N.A.; Crespo, E.A.; Raga, J. A.; Montero, E. E.

2012-01-01

Roč. 19, č. 4 (2012), s. 319-330 ISSN 1252-607X R&D Projects: GA ČR GBP505/12/G112 Institutional support: RVO:60077344 Keywords : Aporocotylidae * Aporocotyle * A. mariachristinae n. sp. * A. ymakara * Genypterus blacodes * Ophidiidae * Patagonia * Argentina * rDNA sequences Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.116, year: 2012

Soñar con el futuro. Proyectos inmigratorios para la Patagonia argentina en Teodoro Alemann y Roberto J. Payró

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Jennifer M. Valko

2014-06-01

Taking into account recent studies on journalistic travel and Argentine nation building, this article examines the profile of a type of reporter that has been studied to a lesser degree, the immigrant journalist. It analyzes two travel chronicles about Patagonia published in Buenos Aires in 1898: Ein Ausflug nach dem Chubut-Territorium [An Excursion to the Chubut Territory] by Swiss journalist Theodor Alemann, published in the German-language newspaper Argentinisches Tageblatt [Argentine Daily], and La australia argentina, by Roberto J. Payró which appeared in La Nación. In both chronicles the narration of the trip to Patagonia is interrupted at a key moment by the telling of a dream regarding the future of the region. This essay demonstrates that these oneiric digressions reveal political and economic interests contrary to the official Argentine plans for the development of the region, the role of immigrants and their relationship with European powers.

A large Cretaceous theropod from Patagonia, Argentina, and the evolution of carcharodontosaurids

Science.gov (United States)

Novas, Fernando E.; Valais, Silvina; Vickers-Rich, Pat; Rich, Tom

2005-05-01

The Cretaceous Carcharodontosauridae is the latest clade of carnosaurs, including the largest predatory dinosaurs yet recorded. Albeit spectacular for their size, the skeletal anatomy of these theropods remains poorly-known, and their diversity was until recently restricted to two Cenomanian species: the highly derived Giganotosaurus carolinii, from southern South America, and the incompletely known Carcharodontosaurus saharicus, from northern Africa. Here we describe an older and basal member of the group, Tyrannotitan chubutensis gen. et sp. nov., from Aptian strata of Patagonia, Argentina. The new taxon gives new insights into the systematics and evolution of carcharodontosaurids and offers a better understanding of the evolution of Southern theropod faunas. We suggest that carcharodontosaurids radiated in Gondwana sharing with spinosaurids the role of top-predators until their extinction in Cenomanian Turonian times. During this interval, the diplodocoid sauropods and giant titanosaurians went extinct (probably as part of a global-scale crisis), and the smaller abelisaurid theropods took dominance, reigning until the end of the Cretaceous. Electronic Supplementary Material is available.

Cystobasidiomycetes yeasts from Patagonia (Argentina): description of Rhodotorula meli sp. nov. from glacial meltwater.

Science.gov (United States)

Libkind, Diego; Sampaio, José Paulo; van Broock, Maria

2010-09-01

A basidiomycetous yeast, strain CRUB 1032(T), which formed salmon-pink colonies, was isolated from glacial meltwater in Patagonia, Argentina. Morphological, physiological and biochemical characterization indicated that this strain belonged to the genus Rhodotorula. Molecular taxonomic analysis based on the 26S rDNA D1/D2 domain and internal transcribed spacer region sequences showed that strain CRUB 1032(T) represents an undescribed yeast species, for which the name Rhodotorula meli sp. nov. is proposed (type strain is CRUB 1032(T)=CBS 10797(T)=JCM 15319(T)). Phylogenetic analysis showed that Rhodotorula lamellibrachii was the closest known species, which, together with R. meli, formed a separate cluster related to the Sakaguchia clade within the Cystobasidiomycetes. Additional Patagonian yeast isolates of the class Cystobasidiomycetes are also investigated in the present work.

The impact of Chilean migration on employment in Patagonia.

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Cariola Sanz, L

1989-06-01

This paper discusses the employment situation of Chilean migrant workers, their impact on labor markets in Patagonia, Argentina, and the government's past and projected responses to this phenomenon. In 1980, Chilean inhabitants of patagonia comprised 11% of the area's population. Chilean migration to patagonia was closely linked to economic activities that began to flourish in the 20th century, such as livestock raising, fruit and vegetable cultivation, and mining for coal and petroleum. No Chilean migrants work in a wide range of sectors. In Patagonia's southern provinces availability and ability to withstand rigorous climate conditions are the main factors which account for the prevalence of Chilean manpower. Chilean migrants do not in general displace local manpower. Legislation and the permeability of the border ensure that most workers enter the country as tourists. Clandestine migration is not an issue. Illegal migrants have provoked negative reactions for several reasons: 1) they comprise a marginal population without formal citizenship; 2) being employed as clandestine workers, they pay no social security, nor do their employers; 3) being illegal, they are obliged to accept lower wages and inferior working conditions which creates unfair competition within labor markets; and 4) as a result of these conditions, xenophobic and endophobic attitudes in relations with Argentine nationalists are reinforced. The government has attempted to solve these problems through various measures. Beginning in 1934, most foreigners entered Argentina with a tourist visa, becoming illegal when they stayed beyond authorized limits. Several measures over the years provided amnesty to illegal migrants. Currently, the law promotes immigration, monitors the admission of foreigners to the country and stipulates their rights and obligations. The law lists 115 articles on immigration promotion and on regulation of the movements of foreigners. Because of the present economic crisis in

Climatology of hail in Argentina

Science.gov (United States)

Mezher, Romina N.; Doyle, Moira; Barros, Vicente

2012-10-01

The annual cycle, annual and seasonal frequency and geographical distribution of hail in Argentina during the 1960-2008 period are examined. Eight regions covering the whole territory were defined based on the correlation of the mean annual hail frequency between all weather stations. Regions lying between 30° and 40°S as well as those dominated by mountains present the highest hail frequencies in Argentina. The eastern and coastal areas of the country experience hail events mainly during springtime but they may start in late winter and continue through the beginning of summer. Events in western and central Argentina also predominate in spring but the maximum frequencies are observed during summer months. Trends in the annual number of hail events calculated for each region indicate that events in northwestern and northeastern Argentina have been increasing as well as in southern Patagonia. On the other hand, in central Argentina, southern Buenos Aires-La Pampa, northern Buenos Aires-Litoral and northern Patagonia trends are negative and statistically significant in the first two regions, basically by the decrease of events during spring and summer.

Condiciones productivas y exigencias de calidad en la fruticultura de la Patagonia argentina

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Belén Alvaro

2013-01-01

Full Text Available La producción alimentaria está regida, a partir de los años noventa, por requerimientos de calidad e inocuidad que modifican sustancialmente las condiciones productivas del eslabón primario, en el marco de una reestructuración del sistema agroalimentario mundial. El caso en estudio aborda la conformación social de la cadena frutícola localizada en el norte de la Patagonia argentina, donde estos requerimientos se formalizan, entre otros, en las buenas prácticas agrícolas, abordadas como dispositivos de control que interpelan y vuelven complejas las condiciones de reproducción social de los chacareros, como productores independientes en la cadena, con impactos en sus trayectorias vitales y productivas. Se consultaron fuentes secundarias, y se realizó el relevamiento primario de casos. Las conclusiones se inscriben en las tensiones entre configuraciones productivas locales y avances de los controles del capital concentrado.

Do native grazers from Patagonia, Argentina, consume the invasive kelp Undaria pinnatifida? ¿Pueden los pastoreadores nativos de Patagonia, Argentina, consumir al alga invasora Undaria pinnatifida?

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S. Valeria Teso

2009-06-01

Full Text Available The invasive kelp Undaria pinnatifida (Phaeophyceae, Laminariales was first reported in Golfo Nuevo in 1992 and since then it has spread widely over more than 170 km, all along the northern Patagonian coast, Argentina. Field observations in the region have indicated the potential role of invertebrate grazers, like the sea urchins Arbacia dufresnii and Pseudechinus magellanicus and the gastropod Tegula patagonica, in controlling algal density. Laboratory experiments were conducted to ascertain whether, and if so, to what extent these grazers actually feed on the algae. The studied sea urchins fed on the alga, whereas the snail scraped off biofouling adhered to its surface. Higher densities of grazers were observed on the kelp during summer and might be attributed to increasing in metabolism with increasing temperature, and degradation of blades and sporophylls, which possibly increase their palatability.El alga invasora Undaria pinnatifida (Phaeophyceae, Laminariales fue reportada por primera vez en Golfo Nuevo en 1992, dispersándose ampliamente a lo largo de 170 km de costa en el norte de la Patagonia, Argentina. Observaciones de campo hechas en los erizos de mar Arbacia dufresnii y Pseudechinus magellanicus y en el gasterópodo Tegula patagonica evidenciaron que son posibles consumidores de Undaria pinnatifida en la población local. Se realizaron experimentos de laboratorio con el objetivo de probar si estos pastoreadores eran capaces de consumir el alga. Los erizos de mar estudiados consumen el alga, mientras que el gasterópodo ramonea los epibiontes presentes sobre su superficie. Altas densidades de ramoneadores fueron encontradas sobre el alga durante el verano y podrían ser atribuidas a un aumento del su metabolismo con el aumento de la temperatura y a la degradación de las láminas y esporofilos, lo cual posiblemente aumente la palatabilidad del alga.

UVR-induced photoinhibition of summer marine phytoplankton communities from Patagonia

NARCIS (Netherlands)

Villafane, Virginia E.; Janknegt, Paul J.; de Graaff, Marco; Visser, Ronald J. W.; de Poll, Willem H. van; Buma, Anita G. J.; Helbling, E. Walter

During austral summer 2006, experiments were carried out to evaluate the effects of ultraviolet radiation (UVR, 280-400 nm) on carbon fixation of natural phytoplankton assemblages from Patagonia (Argentina). Surface water samples were collected (ca. 100 m offshore) at mid morning using an

Geomorphological evidences of Quaternary tectonic activities in the Santa Cruz river valley, Patagonia, Argentina

International Nuclear Information System (INIS)

Massabie, A.; Sanguinetti, A.; Nestiero, O.

2007-01-01

From Argentin lake, at west on Andean hills, to Puerto Santa Cruz on Atlantic coast, Santa Cruz river cross eastward Santa Cruz province over 250 km in Patagonia at southern Argentina. Present bed of the river has a meandering outline with first order meanders of great ratio bends and second order meanders of minor ratio bends. Principal wanderings are 45 to 55 km spaced from near Estancia La Julia or Rio Bote at west to Comandante Luis Piedrabuena at east. On river's bed middle sector these great curvatures are located at Estancia Condor Cliff and Estancia Rincon Grande. Regional and partial detailed studies allow to recognize structural control on river's bed sketch and valley s geomorphology that relates first order bends with reactivated principal faults. These faults fit well with parallel system of northwest strike of Austral Basin.On geological, geomorphologic and structural evidences recognized in Santa Cruz river, quaternary tectonic activity, related to Andean movements in southern Patagonian foreland, is postulated. (author)

A tale of three hydros - post-privatisation in Patagonia

International Nuclear Information System (INIS)

Smith, H.F.

1994-01-01

When Argentina's state-owned utility, operating in northern Patagonia, sold off hydro-electric generating plants in 1993, they were bought by several North American utility companies. This article looks at the problems these companies encountered and examines whether the enterprise has shown itself to be economically valuable. (UK)

Investigación sobre manejo forestal a largo plazo en Patagonia Sur -Argentina: Lecciones del pasado, desafíos del presente Long-term forest management research in South Patagonia - Argentina: Lessons from the past, challenges from the present

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GUILLERMO J MARTÍNEZ-PASTUR

2010-03-01

Full Text Available Argentina ha basado su economía en la agricultura y el ganado, donde el bosque ha sido visto como un obstáculo para el desarrollo. La cosecha forestal en Patagonia Sur ha sido una actividad basada en la colonización y explotación de nuevas áreas. Esta se realiza principalmente en bosques primarios sin ningún manejo silvícola posterior. A pesar de que el manejo actual no es sustentable, la investigación científica ha definido las bases para conservar, proteger y mejorar las propuestas de manejo forestal para los bosques nativos de Patagonia Sur. Las primeras parcelas de estudio a largo plazo (1965-1966 basaron su monitoreo en parámetros económicos y estructura forestal, estableciéndose cerca de veinte parcelas en bosques fiscales de Tierra del Fuego. La mayoría fueron destruidas o discontinuadas debido a la falta de planificación del uso de la tierra, escaso interés social en la investigación, falta de compromiso de instituciones, y poca colaboración con empresas forestales. Posteriormente, un segundo grupo de nueve parcelas se estableció en Patagonia Sur (1993-2004 basado en la colaboración entre empresas privadas e instituciones nacionales. Los objetivos incluyeron parámetros económicos y ecológicos. Las parcelas se establecieron en tierras privadas conjuntamente con empresas privadas y estancieros, mediante la firma de acuerdos y proyectos de investigación. Los principales problemas encontrados fueron: falta de compromiso de las administraciones forestales, ausencia de proyectos financiados a largo plazo, y que la responsabilidad de las parcelas continúa bajo la iniciativa personal de los investigadores participantes. El estudio de las parcelas permitió: (i proponer nuevos sistemas de regeneración basados en la maximización del rendimiento y el mejoramiento del valor de conservación de los bosques manejados (e.g., retención variable y sistemas silvopastoriles, (ii determinar la factibilidad económica de aplicaci

Sexual dimorphism in the mandible of the armadillo Chaetophractus villosus (Desmarest, 1804) (Dasypodidae) from northern Patagonia, Argentina Dimorfismo sexual da mandíbula do tatu Chaetophractus villosus (Desmarest, 1804) (Dasypodidae) do norte da Patagônia Argentina

OpenAIRE

SM. Squarcia; NS. Sidorkewicj; R. Camina; EB. Casanave

2009-01-01

The aim of this study was to study the sexual dimorphism in adult Chaetophractus villosus (Desmarest, 1804), from northern Patagonia, Argentina. Eight mandibular traits were measured in 37 males and 34 females. Univariate and multivariate morphometric analysis were applied to the data set. Results showed that C. villosus was sexually dimorphic, with higher absolute values corresponding to females. The total length of the mandible was the most important variable to discriminate sexes, followed...

Caracterización y modelación del transporte preferencial de plaguicidas organofosforados en suelos productivos bajo riego. Aplicación al Distrito Colonia Centenario, Patagonia Argentina.

OpenAIRE

DUFILHO, ANA CECILIA AMALIA

2016-01-01

[EN] In this thesis, transport and fate of organophosphate pesticides - azinphos-methyl and chlorpyrifos- in productive soils from the valley of the Neuquén River in the Patagonia Argentina are analysed. Climate of the region is arid, so traditional fruit production is under flood irrigation. The soils in the floodplain are predominant Aridisols with textures from sandy loam to clay loam. Methodologically, the thesis was based on: field experiments and data and information processing condu...

Marine pollution effects on the southern surf crab Ovalipes trimaculatus (Crustacea: Brachyura: Polybiidae) in Patagonia Argentina.

Science.gov (United States)

Lezcano, Aníbal Hernán; Rojas Quiroga, María Laura; Liberoff, Ana Laura; Van der Molen, Silvina

2015-02-28

We compared the carapace shape and thickness as well as the energy density of Ovalipes trimaculatus inhabiting areas comprising a gradient of marine pollution: high, moderate and undetected, in the Nuevo gulf (Patagonia Argentina). The carapace shape was evaluated by means of individual asymmetry scores (=fluctuating asymmetry) whereas the carapace thickness was assessed by measuring the carapace dry weight. The energy density was analyzed through its negative relationship with water content in muscle tissue. The individual asymmetry scores as well as the percentage of water content in muscle tissue were proportional to the marine pollution gradient, whereas the carapaces thickness did not differ among sampling sites. Our results are consistent with previous findings and demonstrate the direct effect of marine pollution on other taxa different from gastropods, cephalopods and polyplacophora and add to long-standing concerns about detrimental effects caused by marine pollution on the benthic community of the Nuevo gulf. Copyright © 2014 Elsevier Ltd. All rights reserved.

Volcanic nutrient inputs and trophic state of Lake Caviahue, Patagonia, Argentina

Science.gov (United States)

Pedrozo, Fernando L.; Temporetti, Pedro F.; Beamud, Guadalupe; Diaz, Mónica M.

2008-12-01

The strategies for eutrophication control, remediation, and policy management are often defined for neutral to alkaline freshwater systems, as they are most suitable for human use. The influence of nutrients on eutrophication in a naturally-acidic lake is poorly known. The main purpose of the present work is to evaluate the significance of volcanic nutrients in the control of the trophic state of the acidic Lake Caviahue, located at North Patagonia, Argentina. Acidic water systems were most studied on artificial acidified lakes, such as mining lakes in Germany or pit lakes in the United States. Lake Caviahue received a very high P load (42-192 ton P/yr) and low N load (14 ton N/yr), mainly as ammonium with quite low N:P ratios (Copahue volcano represents the main natural contribution of nutrients and acidity to the Lake Caviahue. The lake is oligotrophic in terms of CHLa. Neither the transparency nor the nutrient, dissolved or particulate, contents are to date representative of the trophic state of the lake. High P loads do not imply the eutrophication of the lake. We suggest that nitrogen and not phosphorus represents the key control nutrient in volcanically acidified lakes as TON was better related to CHLa observed (0.13-0.36 mg/m 3) in the lake. The pH increased around one unit (pH 2.0-3.0) during the last five years suggesting that the lake has not yet returned to a stable state.

Diversity, distribution and floral specificity of tangle-veined flies (Diptera: Nemestrinidae in north west Patagonia, Argentina Diversidad, distribución y especificidad floral de nemestrínidos (Diptera en el noroeste de la Patagonia, Argentina

Directory of Open Access Journals (Sweden)

MARIANO DEVOTO

2006-03-01

Full Text Available Tangle-veined flies (Nemestrinidae constitute a primitive and rather widespread family among Diptera. The genus Trichophthalma occurs in Australia and South America and is the only one in the family with a typically Gondwanian, disjoint distribution. The ecology and distribution of most southern South American species of this genus remains virtually unknown. We studied the diversity, distribution and flower specificity of flower-visiting species of the genus Trichophthalma in the temperate forests of southern South America in ten sites along an east-west rainfall gradient (37-40°S on the eastern slope of the Andes. We recorded nine species of Trichophthalma, which showed an overlapped distribution along the gradient and different degrees of floral specificity. Three species are reported for Argentina for the first time and three are first recorded as flower visitors to the local flora. Our results show that while in southern Africa tangle-veined flies are engaged in highly specialized pollination interactions with long-tubed species, the Trichophthalma spp. of Patagonia share their flowers with a diverse and rather unspecialized visitor fauna among which several species of flies, bees and birds are presentLos nemestrínidos constituyen una familia de Dípteros primitiva y de amplia distribución. El género Trichophthalma se encuentra en Australia y Sudamérica y es el único en la familia con una distribución disjunta típicamente gondwánica. La ecología y distribución de la mayoría de las especies sudamericanas permanecen virtualmente desconocidas. Estudiamos la diversidad, distribución y especificidad floral de las especies del género Trichophthalma de los bosques templados del sur de Sudamérica en diez sitios ubicados a lo largo de un gradiente de precipitación este-oeste (37-40°S sobre la vertiente occidental de los Andes. Registramos nueve especies de Trichophthalma, las cuales mostraron una distribución superpuesta a lo largo

Morfometría externa y reparto de recursos en zorros simpátricos (Pseudalopex culpaeus y P. griseus) en el sureste de la Patagonia Argentina

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Zapata, Sonia C.; Procopio, Diego E.; Martínez-Peck, Rolando; Zanón, Juan I.; Travaini, Alejandro

2008-01-01

Estudios previos han demostrado que el tamaño corporal de zorros grises o chillas (Pseudalopex griseus) y colorados o culpeos (P. culpaeus) es similar en alopatría, y que en simpatría se produce una divergencia en el tamaño de ambos zorros. El aumento en la diferencia del tamaño corporal entre las dos especies hacia la porción más austral de su distribución (Patagonia Argentina y sur de Chile) permitiría una especialización hacia diferentes recursos favoreciendo su coexistencia. Sin embargo, ...

A Water Resources Management Model to Evaluate Climate Change Impacts in North-Patagonia, Argentina

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Bucciarelli, L. F.; Losano, F. T.; Marizza, M.; Cello, P.; Forni, L.; Young, C. A.; Girardin, L. O.; Nadal, G.; Lallana, F.; Godoy, S.; Vallejos, R.

2014-12-01

Most recently developed climate scenarios indicate a potential future increase in water stress in the region of Comahue, located in the North-Patagonia, Argentina. This region covers about 140,000 km2 where the Limay River and the Neuquén River converge into the Negro River, constituting the largest integrated basins in Argentina providing various uses of water resources: a) hydropower generation, contributing 15% of the national electricity market; b) fruit-horticultural products for local markets and export; c) human and industrial water supply; d) mining and oil exploitation, including Vaca Muerta, second world largest reserves of shale gas and fourth world largest reserves of shale-oil. The span of multiple jurisdictions and the convergence of various uses of water resources are a challenge for integrated understanding of economically and politically driven resource use activities on the natural system. The impacts of climate change on the system could lead to water resource conflicts between the different political actors and stakeholders. This paper presents the results of a hydrological simulation of the Limay river and Neuquén river basins using WEAP (Water Evaluation and Planning) considering the operation of artificial reservoirs located downstream at a monthly time step. This study aims to support policy makers via integrated tools for water-energy planning under climate uncertainties, and to facilitate the formulation of water policy-related actions for future water stress adaptation. The value of the integrated resource use model is that it can support local policy makers understand the implications of resource use trade-offs under a changing climate: 1) water availability to meet future growing demand for irrigated areas; 2) water supply for hydropower production; 3) increasing demand of water for mining and extraction of unconventional oil; 4) potential resource use conflicts and impacts on vulnerable populations.

A single haplotype hyposensitive to light and requiring strong vernalization dominates Arabidopsis thaliana populations in Patagonia, Argentina.

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Kasulin, Luciana; Rowan, Beth A; León, Rolando J C; Schuenemann, Verena J; Weigel, Detlef; Botto, Javier F

2017-07-01

The growing collection of sequenced or genotyped Arabidopsis thaliana accessions includes mostly individuals from the native Eurasian and N. African range and introduced North American populations. Here, we describe the genetic and phenotypic diversity, along with habitats and life history, of A. thaliana plants collected at the southernmost end of its worldwide distribution. Seed samples were harvested from plants growing in four sites within a ~3500-km 2 -area in Patagonia, Argentina, and represent the first germplasm to be collected in South America for this species. Whole-genome resequencing revealed that plants from the four sites and a Patagonia herbarium specimen collected in 1967 formed a single haplogroup (Pat), indicating that the phenotypic variation observed in the field reflected plastic responses to the environment. admixture and principal components analyses suggest that the ancestor of the Pat haplogroup either came from Italy or the Balkan/Caucasus regions of Eurasia. In the laboratory, plants from the Pat haplogroup were hyposensitive to continuous red (Rc) and shade light, with corresponding changes in the expression of phytochrome signalling genes. Pat had higher PIF3 and PIF5 and lower HY5 expression under Rc light; and lower expression of PIL1, ATHB2 and HFR1 under shade compared to Col-0. In addition, Pat plants had a strong vernalization requirement associated with high levels of FLC expression. We conclude that including Pat in studies of natural variation and in comparison with other introduced populations will provide additional information for association studies and allow for a more detailed assessment of the demographic events following colonization. © 2017 John Wiley & Sons Ltd.

NREL technical assistance to Argentina

Energy Technology Data Exchange (ETDEWEB)

Lilienthal, P. [National Renewable Energy Lab., Golden, CO (United States)

1997-12-01

This paper describes assistance to Argentina from the National Renewable Energy Laboratory which has touched on four programs: tariff analysis for rural concessions programs; wind/diesel hybrid retrofits in Patagonia; small hybrid systems designs for rural schools; an assessment of wind resources. The paper expands briefly on the first two points.

A new species of Ascocotyle (Trematoda: Heterophyidae) from the South American sea lion, Otaria flavescens, off Patagonia, Argentina.

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Hernández-Orts, Jesús Servando; Montero, Francisco Esteban; Crespo, Enrique Alberto; García, Néstor Aníbal; Raga, Juan Antonio; Aznar, Francisco Javier

2012-08-01

We describe a new heterophyid species, Ascocotyle (Ascocotyle) patagoniensis n. sp., based on specimens collected from the intestines of the South American sea lion Otaria flavescens from Patagonia (Argentina). Ascocotyle (A.) patagoniensis n. sp. is distinguished from the other species of the subgenus by the number of circumoral spines, which are arranged in 2 rows of 18 to 23. The new species also differs from the other species in having a gonotyl without papillae. The specimens exhibited the widest seminal receptacle described for a species of this subgenus. Species of the subgenus Ascocotyle usually infect fish-eating birds or mammals in freshwater or brackish habitats. Ascocotyle (A.) patagoniensis n. sp. is the first species of the subgenus described from a marine mammal. However, no metacercariae of Ascocotyle spp. were found in 542 marine teleosts from 20 species collected in the same locality. The life cycle of the marine species from the Ascocotyle -complex infecting pinnipeds remains elusive.

Solapamiento trófico entre el lobo marino de un pelo Otaria flavescens y la pesquería de arrastre demersal del golfo San Matías, Patagonia, Argentina Trophic overlap between the South American sea lion Otaria flavescens and the demersal trawl fishery in San Matías Gulf, Patagonia, Argentina

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María Alejandra Romero

2011-07-01

Full Text Available A nivel internacional, paralelo a la declinación y al colapso de pesquerías de gran escala, surgió un interés creciente por el estudio de las interacciones entre mamíferos marinos y pesquerías. El golfo San Matías (Patagonia, Argentina es considerado un ecosistema pesquero independiente de las aguas de la Plataforma Continental Argentina, con condiciones oceanográficas y biológicas particulares. La condición de sistema semi-cerrado podría generar escenarios particulares para la interacción entre la flota pesquera de arrastre de fondo y la población de lobos marinos de un pelo Otaria flavescens. En el presente trabajo se caracterizó la dieta del predador y la composición de las capturas pesqueras a fin de evaluar el solapamiento trófico entre ambos componentes. A partir de este análisis y la comparación de las tallas de las presas consumidas, se encontró que la posibilidad de una interacción competitiva entre la flota pesquera y los lobos marinos, a partir de la utilización de recursos similares, sería baja en el ecosistema del golfo San Matías.As world fisheries began to decline and massive collapses were observed, the competition between marine mammals and fisheries became an issue of growing concern. San Matías Gulf (Patagonia, Argentina is considered to be a fishery ecosystem independent of the Argentine Continental Shelf waters, with particular oceanographic and biological properties. As a semi-enclosed ecosystem, this gulf may generate particular scenarios for interactions between the demersal trawl fishery fleet and the population of South American sea lions Otaria flavescens. In this paper, the diet of the top predator and the composition of fishery catches were characterized in order to assess the trophic overlap between these two components. This analysis and a comparison of the sizes of prey consumed revealed a low probability of competition for similar resources between the fishing fleet and the marine mammals

Relative Paleointensity of the Geomagnetic Field 12-20 kyr. From Sediment Cores, Lake Moreno (Patagonia, Argentina)

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Gogorza, C. S.; Irurzun, M. A.; Chaparro, M. A.; Lirio, J. M.; Nunez, H.; Sinito, A. M.

2007-05-01

, M.A.E. Chaparro, J.M. Lirio, H. Nunez, P.G. Bercoff, A.M. Sinito. Relative paleointensity of the geomagnetic field over the last 21,000 years BP from sediment cores, Lake El Trébol (Patagonia, Argentina). Earth Planet Space. 58: 1323-1332, 2006.

Cuatro nuevas especies del género Liolaemus (Iguania: Liolaemidae, pertenecientes al grupo boulengeri, de la Patagonia, Argentina

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Abdala, Cristian Simón

2003-12-01

Full Text Available Se describen cuatro nuevas especies del género Liolaemus, pertenecientes al grupo boulengeri, caracterizado por la presencia de un parche femoral de escamas agrandadas en la parte posterior del fémur. Una especie fue colectada en el sur de la provincia de Neuquén y las otras tres en el suroeste, centro y este de la provincia de Río Negro, en la Patagonia Argentina. Dentro del grupo las nuevas especies están relacionadas fenéticamente a Liolaemus boulengeri. Se estudiaron 98 caracteres morfológicos externos, referidos principalmente a caracteres de lepidosis, patrón de coloración y proporciones corporales, corrientemente estudiados en Liolaemus. Las diferencias más significativas entre estas especies y Liolaemus boulengeri se dan principalmente en el patrón de coloración y en algunos caracteres de escamación. Estas especies ocupan parte de las tres regiones patagónicas que se diferencian con base en la orografía y vegetación asociada. Las nuevas especies del centro y suroeste de la provincia de Río Negro, soportan grandes diferencias de temperatura diarias y estacionales. Las cuatro especies que se describen aquí se alimentan principalmente de insectos. Four new species of Liolaemus are described from the Patagonia region of southern Argentina. One species was collected in southern Neuquén Province and the other three are from Río Negro Province. Each of the new species has a patch of enlarged scales on the posterior surface of the thighs, indicating their relationship to members of the boulengeri group. Within this group, the four new species are morphologically most similar, and may be most closely related to, Liolaemus boulengeri. A total of 98 external morphological characters, principally squamation, color pattern, and body proportions, were recorded for these new members of the boulengeri group and compared with those for Liolaemus boulengeri. Significant differences between the new species and Liolaemus boulengeri were

Estado del conocimiento taxonómico de la fauna de Chironomidae (Diptera: Nematocera de la Patagonia Current state of the taxonomic knowledge of the Chironomidae fauna (Diptera: Nematocera from Patagonia

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Mariano Donato

2009-06-01

Full Text Available La familia Chironomidae (Diptera: Nematocera es uno de los grupos de insectos más ampliamente distribuidos y abundantes en cuerpos de agua dulce. Los representantes de esta familia pueden explotar áreas con amplios gradientes ambientales. La información que se presenta está basada en la recopilación de datos distribucionales bibliográficos, del estudio del material tipo de las especies de Chironomidae depositadas en el Natural History Museum (UK y del material de colección del Museo de La Plata (Argentina. En la Patagonia, se registran 9 subfamilias, la subfamilia monotípica Chilenomyiinae es endémica de esta área. Dentro de estas subfamilias, 53 de los 111 géneros conocidos para América del Sur están presentes en la Patagonia. Del total de géneros de la Patagonia, el 20 % es endémico y 7 de ellos muestran relaciones transantárticas. En la Patagonia, se registran 177 especies de Chironomidae, el 98% de éstas son endémicas, el 3 % son consideradas nomina dubia y el 17% requiere revisión ya que su ubicación sistemática es dudosa. Las descripciones originales de las especies patagónicas de Chironomidae están basadas principalmente sobre machos (n=58 y machos y hembras (n=43, ambas representan el 57% del total; el resto de las especies han sido descriptas con diferentes combinaciones de estadios del ciclo de desarrollo.The Chironomidae (Diptera: Nematocera family is one of the most widely distributed group of insects and often the most abundant in freshwater environments. Representatives of this family can exploit a wide range of environmental gradients. The information here presented is based on the compilation of distributional data obtained from bibliography, the study of the type material deposited in the Natural History Museum (UK and the collection material from Museo de La Plata (Argentina. Nine subfamilies are recorded from Patagonia, being the monotypic subfamily Chilenomyiinae endemic for the area. From the 111 known

Late Cretaceous paleosols as paleoclimate proxies of high-latitude Southern Hemisphere: Mata Amarilla Formation, Patagonia, Argentina

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Varela, Augusto N.; Raigemborn, M. Sol; Richiano, Sebastián; White, Tim; Poiré, Daniel G.; Lizzoli, Sabrina

2018-01-01

Although there is general consensus that a global greenhouse climate characterized the mid-Cretaceous, details of the climate state of the mid-Cretaceous Southern Hemisphere are less clearly understood. In particular, continental paleoclimate reconstructions are scarce and exclusively derived from paleontological records. Using paleosol-derived climofunction studies of the mid- to Upper Cretaceous Mata Amarilla Formation, southern Patagonia, Argentina, we present a reconstruction of the mid-Cretaceous climate of southern South America. Our results indicate that at 60° south paleolatitude during the Cenomanian-Santonian stages, the climate was subtropical temperate-warm (12 °C ± 2.1 °C) and humid (1404 ± 108 mm/yr) with marked rainfall seasonality. These results are consistent with both previous estimations from the fossil floras of the Mata Amarilla Formation and other units of the Southern Hemisphere, and with the previous observations of the displacement of tropical and subtropical floras towards the poles in both hemispheres. The data presented here show a more marked seasonality and slightly lower mean annual precipitation and mean annual temperature values than those recorded at the same paleolatitudes in the Northern Hemisphere.

Reproductive biology of Sympterygia bonapartii (Chondrichthyes: Rajiformes: Arhynchobatidae in San Matías Gulf, Patagonia, Argentina

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María L. Estalles

2017-04-01

Full Text Available ABSTRACT This study estimates and analyses the reproductive parameters and cycle of Sympterygia bonapartii in San Matías Gulf, northern Patagonia, Argentina. A total of 827 males and 1,299 females were analysed. Males ranged from 185 to 687 mm of total length (TL and females from 180 to 742 mm TL. Sexual dimorphism was detected; females were larger, heavier, exhibited heavier livers, wider discs and matured at lager sizes than males. Immature females ranged from 180 to 625 mm TL, maturing females from 408 to 720 mm TL, mature ones from 514 to 742 mm TL and females with egg capsules from 580 to 730 mm TL. Immature males ranged from 185 to 545 mm TL, maturing ones from 410 to 620 mm TL and mature males from 505 to 687 mm TL. Size at which 50% of the skates reached maturity was estimated to be 545 mm TL for males and 594 mm TL for females. According to the reproductive indexes analysed, S. bonapartii exhibited a seasonal reproductive pattern. Mating may occur during winter-early spring and the egg-laying season, during spring and summer.

Transboundary protected area proposals along the Southern Andes of Chile and Argentina: Status of current efforts

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Peter Keller

2007-01-01

An evolving network of protected areas along the southern Andes of Chile and Argentina-the heart of Patagonia-are in various stages of evaluation and potential Transboundary Protected Area designations. This paper examines three such efforts. The first proposal is the North Andean-Patagonia Regional Eco-Corridor, which was the subject of a recent bilateral meeting...

Using dental enamel wrinkling to define sauropod tooth morphotypes from the Cañadón Asfalto Formation, Patagonia, Argentina.

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Femke M Holwerda

Full Text Available The early Middle Jurassic is regarded as the period when sauropods diversified and became major components of the terrestrial ecosystems. Not many sites yield sauropod material of this time; however, both cranial and postcranial material of eusauropods have been found in the Cañadón Asfalto Formation (latest Early Jurassic-early Middle Jurassic in Central Patagonia (Argentina, which may help to shed light on the early evolution of eusauropods. These eusauropod remains include teeth associated with cranial and mandibular material as well as isolated teeth found at different localities. In this study, an assemblage of sauropod teeth from the Cañadón Asfalto Formation found in four different localities in the area of Cerro Condor (Chubut, Argentina is used as a mean of assessing sauropod species diversity at these sites. By using dental enamel wrinkling, primarily based on the shape and orientation of grooves and crests of this wrinkling, we define and describe three different morphotypes. With the exception of one taxon, for which no cranial material is currently known, these morphotypes match the local eusauropod diversity as assessed based on postcranial material. Morphotype I is tentatively assigned to Patagosaurus, whereas morphotypes II and III correspond to new taxa, which are also distinguished by associated postcranial material. This study thus shows that enamel wrinkling can be used as a tool in assessing sauropod diversity.

Using dental enamel wrinkling to define sauropod tooth morphotypes from the Cañadón Asfalto Formation, Patagonia, Argentina.

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Holwerda, Femke M; Pol, Diego; Rauhut, Oliver W M

2015-01-01

The early Middle Jurassic is regarded as the period when sauropods diversified and became major components of the terrestrial ecosystems. Not many sites yield sauropod material of this time; however, both cranial and postcranial material of eusauropods have been found in the Cañadón Asfalto Formation (latest Early Jurassic-early Middle Jurassic) in Central Patagonia (Argentina), which may help to shed light on the early evolution of eusauropods. These eusauropod remains include teeth associated with cranial and mandibular material as well as isolated teeth found at different localities. In this study, an assemblage of sauropod teeth from the Cañadón Asfalto Formation found in four different localities in the area of Cerro Condor (Chubut, Argentina) is used as a mean of assessing sauropod species diversity at these sites. By using dental enamel wrinkling, primarily based on the shape and orientation of grooves and crests of this wrinkling, we define and describe three different morphotypes. With the exception of one taxon, for which no cranial material is currently known, these morphotypes match the local eusauropod diversity as assessed based on postcranial material. Morphotype I is tentatively assigned to Patagosaurus, whereas morphotypes II and III correspond to new taxa, which are also distinguished by associated postcranial material. This study thus shows that enamel wrinkling can be used as a tool in assessing sauropod diversity.

Spatial distribution, feeding and length–mass relationships of Diamphipnopsis samali (Plecoptera, Diamphipnoidae in a North Patagonia Andean stream, Argentina

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Guillermo H. OMAD

2015-01-01

Full Text Available RESUMEN. Fueron estudiados algunos aspectos de la biología y ecología (patrones de distribución espacial, hábitos alimenticios y relación largo-masa de una población de Diamphipnopsis samali en un arroyo de primer orden que atraviesa un bosque exótico de pino en el centro-norte de Patagonia (Chubut, Argentina. Dos series de muestreos fueron realizados durante períodos de aguas altas y aguas bajas. Toda la información fue tratada con ANOVAS de dos factores y efectos fijos para evaluar diferencias significativas. El análisis de las piezas bucales de D. samali indica que corresponden a un tipo intermedio entre el tipo carnívoro y herbívoro-detritívoro. El contenido estomacal muestra que esta especie se alimenta de hifas fúngicas y madera, aunque en los estadios tempranos se encuentran restos de insectos. No se hallaron diferencias significativas en la alimentación entre períodos de aguas altas y aguas bajas, sin embargo, existieron diferencias significativas entre la dieta de larvas grandes y pequeñas. Fue clara la preferencia por el sustrato tronco y cascada, y también significativamente diferente entre los tipos pozón y corredera. No hubo diferencias significativas en la elección de hábitat entre los períodos de aguas bajas y aguas altas. Esta especie endémica de Patagonia parece estar bien adaptada a la presencia de un bosque ripario exótico, utilizando los troncos caídos como alimento y refugio.

Fe-Ni Micrometorites from Upper Jurassic Cañadon Asfalto Fm., Patagonia, Argentina

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Matteini, M.; Hauser, N.; Cabaleri, N.; Silva Nieto, D.; Cuadros, F. A.; Reyes, S.

2014-09-01

Microspherules from an upper Jurassic sediments from Patagonia, show mineralogical, geochemical and textural features very similar to those reported for I-type micrometeorites whereas some spherules are interpreted as typical G-type micrometeorites.

Monopolizar la violencia en una frontera colonial. Policías y militares en Patagonia austral (Argentina y Chile, 1870-1922

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Alberto Harambour R.

2016-01-01

Full Text Available Este artículo analiza la monopolización de la violencia en el ciclo inicial de colonización de Patagonia austral para lo cual propone, primero, que la precariedad local de los Estados de Argentina y Chile descansó en la fuerza expansiva de la industria ganadera para la instalación de su sobe- ranía territorial; y segundo, que la clausura de la delimitación fronteriza solo se produjo en el verano de 1922, como resultado de la represión a la insurgencia obrera. A partir de una extensa investigación en fuentes oficiales y empresariales referidas a Santa Cruz, Magallanes y Tierra del Fuego, así como en la prensa local, se investiga y compara la presencia de la fuerza policial y militar en las subdivisiones administrativas del extremo sur; además se examinaron similitudes y diferencias en las estra- tegias de control social.

Desarrollo morfológico y conductual de pollos del aguilucho chico Buteo albigula (Aves: Accipitridae en el noroeste de la Patagonia argentina Morphologic and behavioral development of white-throated hawk Buteo albigula (Aves: Accipitridae nestlings in northwestern Argentine Patagonia

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VALERIA OJEDA

2003-09-01

Full Text Available El desarrollo morfológico y conductual del aguilucho chico (Buteo albigula en el nido fue estudiado en cercanías de San Carlos de Bariloche, al noroeste de la Patagonia argentina. El estudio se basó en el seguimiento de dos pollos producidos en diferentes nidos en la temporada reproductiva 2001-2002, y se lo complementó con datos tomados ad libitum en otros nidos, esa misma y anteriores temporadas. Los pollos permanecieron en el nido por aproximadamente seis semanas. Durante su desarrollo morfológico se evidenciaron diversos cambios; notablemente, la aparición secuencial de dos plumones natales, que solo fue observada entre especies de Buteo neotropicales, para B. brachyurus. La conducta de los pollos se encuadró en los patrones comunes para otras especies de Buteo de tamaño corporal similar. Además, se caracterizó, por primera vez para la Argentina, un juvenil (muerto accidentalmente, y se tomaron medidas y peso (por primera vez para B. albigula de dos adultos anillados cerca de sus nidos. El juvenil fue relativamente similar al descrito en Chile. Los adultos, que serían los primeros aguiluchos chicos en ser anillados, se suman a los escasos ejemplares medidos en el área reproductiva conocida de la especie.The morphological and behavioral development of white-throated hawk (Buteo albigula nestlings was studied near San Carlos de Bariloche, in northwestern Argentine Patagonia. The study was mainly based on the monitoring of two nestlings produced at different nests during 2001-2002 breeding season, and was reinforced with data obtained at libitum in other nests the same and previous breeding seasons. The nestling period extended for approximately 6 weeks. Morphological development was characterized by several changing features, but the most surprising was the development of first and second natal down, which was only known, among Neotropical Buteo species, for B. brachyurus. Nestling behavioral development matched the general

Selected contributions from the 9th International Conference on Tidal Sedimentology, November 2015, Puerto Madryn, Patagonia, Argentina: an introduction

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Scasso, Roberto A.; Cuitiño, José I.

2017-08-01

This special issue of Geo-Marine Letters presents selected contributions from the 9th International Conference on Tidal Sedimentology held on 17-19 November 2015 in Puerto Madryn, Chubut Province, Patagonia, Argentina. The guest editors are the conference organizers Roberto A. Scasso and José I. Cuitiño. Gerardo M. Perillo was the head of the Scientific Committee. The conferences on tidal sedimentology have been traditionally held every 4 years. However, only 3 years separated the last conference held in Caen (France, 2012) from this conference. Increasing numbers of contributions and the growing interest in tidal sedimentation have been the reasons for shortening the inter-conference period. The 2015 conference served as a discussion forum focusing on advances in modern and ancient tidal sedimentation at different locations worldwide. The papers presented in this Special Issue provide a selective view of the latest research results, the main topics dealing with tidal hydrodynamics and sediment transport, tidal coastal morphodynamics, modern and ancient tidal sedimentation, geotechnical processes in tidal environments, and tidal basins, facies and reservoirs.

Difilobotriasis humana en la Patagonia, Argentina

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Semenas Liliana

1997-01-01

Full Text Available OBJETIVO: El objetivo del trabajo fué detectar hospedadores humanos en la zona andino patagónica argentina, teniendo en cuenta las prácticas de pesca desportiva y la importancia de los salmónidos dentro de la zona. MATERIAL Y METODO: Entre 1986 y 1995 se implementaron Campañas de Información en los laboratorios de Análisis Clínicos de la región andinopatagónica argentina, destinadas a lograr una detección más eficiente de la difilobotriasis, a través de análisis coproparasitológicos. RESULTADOS: Adicionalmente, se confeccionaron planillas destinadas a recoger información sobre las características de la infección, del tratamiento y del paciente. Durante este período se detectaron 13 nuevos casos humanos, por identificación directa del parásito o por la presencia de huevos en materia fecal. Las características de las infecciones responden a las descriptas para el género Diphyllobothrium. CONCLUSIONES: En la región, los salmónidos son los peces predilectos en la pesca deportiva. Estos peces, frecuentemente parasitados con larvas, constituyen la principal fuente de contagio para el hombre al ser consumidos insuficientemente cocidos o ahumados en frío.

Difilobotriasis humana en la Patagonia, Argentina

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Liliana Semenas

1997-06-01

Full Text Available OBJETIVO: El objetivo del trabajo fué detectar hospedadores humanos en la zona andino patagónica argentina, teniendo en cuenta las prácticas de pesca desportiva y la importancia de los salmónidos dentro de la zona. MATERIAL Y METODO: Entre 1986 y 1995 se implementaron Campañas de Información en los laboratorios de Análisis Clínicos de la región andinopatagónica argentina, destinadas a lograr una detección más eficiente de la difilobotriasis, a través de análisis coproparasitológicos. RESULTADOS: Adicionalmente, se confeccionaron planillas destinadas a recoger información sobre las características de la infección, del tratamiento y del paciente. Durante este período se detectaron 13 nuevos casos humanos, por identificación directa del parásito o por la presencia de huevos en materia fecal. Las características de las infecciones responden a las descriptas para el género Diphyllobothrium. CONCLUSIONES: En la región, los salmónidos son los peces predilectos en la pesca deportiva. Estos peces, frecuentemente parasitados con larvas, constituyen la principal fuente de contagio para el hombre al ser consumidos insuficientemente cocidos o ahumados en frío.

EXPERIENCIA OBRERA, CONSTRUCCIONES SINDICALES Y OR-GANIZACIONES POLÍTICAS DE LA CLASE OBRERA: LOS TRABA-JADORES DE LA PATAGONIA ARGENTINA DURANTE LA DÉCA-DA DEL ‘80

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Gonzalo Pérez Álvarez

2015-09-01

Full Text Available Exploramos la relación entre experiencia obrera y organización partidaria de los trabajadores, a partir del estudio de la experiencia que desarrolla un conjunto de trabajadores afincados en la Patagonia argentina durante el auge del proyecto de promoción industrial para la región. Para ello describiremos algunas experiencias de organización partidaria de grupos obreros, intentando problematizar la búsqueda que realizan estos trabajadores de construir programas políticos propios, los límites y potencialidades que se expresan y el intento de desarrollar propuestas alternativas a las conducciones sindicales tradicionales. Señalamos los momentos de quiebre de esta experiencia, y la relación que guardan con la transformación en la estructura económica de la región. La consolidación hegemónica del neoliberalismo necesitaba la destrucción de las construcciones que pudiesen plantear proyectos alternativos al del capital financiero.Palabras clave: Experiencia, sindicatos, partidos políticos, clase obrera._________________________We explore the relationship between working experience and party organization of workers, from the study of the experience that develops a set of workers settled in Patagonia Argentina during the rise of industrial promotion project for the region. This will describe some experiences of party organization groups of workers, trying to problematize the search performed by these workers to build own political agendas, the limits and potentialities that are expressed and the attempt to develop al-ternative approaches to traditional union lines. Note the break in time of this experience, and how they relate to the transformation in the economic structure of the region. The hegemonic consolidation of neoliberalism needed destruction of buildings that may pose alternative to finance capital projects.Keywords: Experience, trade unions, political parties, working class.

Especies de Ulva del Golfo San Jorge, Patagonia Argentina: variaciones bioquímicas estacionales - espaciales y su relación con la producción de metabolitos bioactivos

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Analía Verónica Uhrich

Full Text Available Objetivos: Investigar especies de Ulva del Golfo San Jorge, Patagonia Argentina, integrando aspectos bioquímicos, actividad biológica y variaciones estacionales/habitacionales que permitan determinar su potencial aplicación en Salud. Métodos: Las algas se colectaron estacionalmente en playas con y sin contaminación antrópica; se secaron, molieron y extrajeron con etanol. Los extractos se fraccionaron mediante solventes de distinta polaridad. Cada fracción fue caracterizada mediante reacciones químicas cualitativas y cromatografía. Las fracciones ricas en flavonoides se analizaron por HPLC-DAD y los lípidos, por TLC. La actividad biológica se ensayó mediante el test de citotoxicidad de Artemia salina, inhibición de la elongación radicular, inhibición de la xantino oxidasa, actividad antioxidante y antibacteriana. Resultados: Se identificaron Ulva rigida y Ulva lactuca. Ambas evidenciaron flavonoides, taninos, quinonas, lípidos, carbohidratos, esteroides. Los flavonoides resultaron mayoritarios en U. rigida (otoño e invierno y en U. lactuca (primavera e invierno, destacándose kayaflavona. Se detectaron alcaloides en Ulva rigida (verano. Los lípidos fueron mayoritarios en verano; U. lactuca en invierno mostró monogalactosildiacilglicérido y en otoño, digalactosilacilglicérido y fosfatidilcolina. La actividad inhibitoria de la elongación radicular, que presume actividad antitumoral, fue importante y dosis dependiente, destacándose U. rigida de otoño y primavera (DE50= 480 y 520 µg/ml, respectivamente. Las demás bioactividades resultaron escasas o negativas. Conclusiones: Las variaciones metabólicas observadas muestran la importancia de considerar las condiciones espacio - temporales al planificar una colecta de ejemplares para su estudio y/o aplicación. Este primer análisis integral de especies de Ulva de la Patagonia Argentina, evidencia su potencialidad como antitumoral.

Fluid typing and tortuosity analysis with NMR-DE techniques in volcaniclastic reservoirs, Patagonia/Argentina

Energy Technology Data Exchange (ETDEWEB)

Bustos, Ulises Daniel [Schlumberger Argentina S.A., Buenos Aires (Argentina); Breda, Eduardo Walter [Repsol YPF Comodoro Rivadavia, Chubut (Argentina)

2004-07-01

Alternative hydrocarbon-detection techniques are used to differentiate water from hydrocarbon where resistivity-based methods are difficult to apply, such as freshwater reservoirs and complex lithologies. One of these areas is represented by the complex volcaniclastic freshwater reservoirs in the Golfo San Jorge basin, Patagonia Argentina, where water and oil have often identical response on conventional logs. Some advances in hydrocarbon identification based on nuclear magnetic resonance (NMR) techniques were achieved in long T1 environments (very light oils, gas) in the Golfo San Jorge basin by previous NMR fluid typing methods. However, since medium to heavy oils are commonly present in these intervals, hydrocarbon detection by such techniques cannot be properly achieved. In addition, restricted diffusion phenomena recognized in these intervals, constitute further complications in fluid typing since its presence have similar response than native oil. To address this problem, a fluid characterization method using NMR Diffusion-Editing techniques and processing/interpretation with D-T2 maps in a suite of NMR measurements was applied. The technique allowed the detection and evaluation of restricted diffusion in these reservoirs, enabling better hydrocarbon characterization in a broad viscosity range (from light to heavy). The method also improved the petrophysical evaluation because restricted diffusion is related to tortuosity in the reservoir. Since the application of this innovative reservoir evaluation method, fluid prognosis vs well completion results was increased from around 68% to around 88% in Golfo San Jorge basin. Moreover, in some of these areas rates above 95% were recently achieved in 2004. (author)

High abundance and diversity of consumers associated with eutrophic areas in a semi-desert macrotidal coastal ecosystem in Patagonia, Argentina

Science.gov (United States)

Martinetto, Paulina; Daleo, Pedro; Escapa, Mauricio; Alberti, Juan; Isacch, Juan Pablo; Fanjul, Eugenia; Botto, Florencia; Piriz, Maria Luz; Ponce, Gabriela; Casas, Graciela; Iribarne, Oscar

2010-07-01

Here we evaluated the response to eutrophication in terms of abundance and diversity of flora and fauna in a semi-desert macrotidal coastal system (San Antonio bay, Patagonia, Argentina, 40° 48' S) where signs of eutrophication (high nutrient concentration, seaweed blooms, high growth rate of macroalgae) have been reported. We compared abundances and species composition of macroalgae, small infaunal and epifaunal invertebrates, and birds associated with tidal channels of the San Antonio Bay subject to contrasting anthropogenic influence. Macroalgae were more abundant and diverse in the channel closer to human activity where nutrient concentrations were also higher. In contrast to what others have observed in eutrophic sites, small invertebrates and birds were also more abundant and diverse in the channel with macroalgal blooms and high nutrient concentration. The large water flushing during the tidal cycle could prevent anoxic or hypoxic events, making the environment suitable for consumers. Thus, this could be a case in which eutrophication supports high densities of consumers by increasing food availability, rather than negatively affecting the survival of organisms.

Territorio y ganadería en la Patagonia Argentina: desertificación y rentabilidad en la Meseta Central de Santa Cruz

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Larry Andrade

2002-01-01

Full Text Available El artículo revisa brevemente las características que asume el proceso de desertificación en la Patagonia Austral, con énfasis en la provincia de Santa Cruz, Argentina. Se hacen referencias a la ocupación del territorio santacruceño por el ganado ovino, a fines del siglo XIX y con más intensidad a principios del siglo XX, y el impacto que ello conllevó, especialmente el desencadenamiento de un proceso erosivo (desertificación, producido básicamente por el pastoreo constante (sobrepastoreo del pastizal natural. También se encuentran referencias al sector ganadero y su participación en el producto bruto geográfico (PBG de Santa Cruz y, hacia el final, un análisis comparativo de la cantidad de animales que el productor estima que puede sostener en su campo y la cantidad que el Instituto Nacional de Tecnología Agropecuaria (INTA, con base en relevamientos de pastizal, calcula que podría mantener.

Levels of essential and toxic elements in Porphyra columbina and Ulva sp. from San Jorge Gulf, Patagonia Argentina

International Nuclear Information System (INIS)

Perez, Adriana Angela; Farias, Silvia Sara; Strobl, Analia Mabel; Perez, Laura Beatriz; Lopez, Clara Magdalena; Pineiro, Adriana; Roses, Otmaro; Fajardo, Maria Angelica

2007-01-01

Baseline concentration levels of As, B, Ca, Cd, Cr, Cu, Co, Fe, Mg, Mn, Mo, Ni, P, Pb, Se, V, and Zn were determined for Porphyra columbina and Ulva sp. collected from three locations along San Jorge Gulf, in Patagonia Argentina. Elements were quantified by inductively coupled plasma-optical emission spectrometry, with the exception of lead and cadmium in some samples which were determined by electrothermal atomic absorption spectrometry. Three stations with different exposure degree to human activities, Bahia Solano, the mouth of Arroyo La Mata stream and Punta Maqueda, were selected as sampling points. The results showed a wide range of metal retention capacity between the two studied species. Regarding the levels of pollutants found in the researched sites, Punta Maqueda seemed to be less influenced by anthropogenic activities than the other two sites except for Cd. Taking into account their toxicities seasonal variations in Pb and Cd levels were studied in both algae in Punta Maqueda. Maximum concentrations of Cd (9.8 μg g -1 dry wt.) were observed in P. columbina during winter, and maximum levels of Pb (0.82 μg g -1 dry wt.) were detected in Ulva sp. during summer. Legislative and health safety aspects were evaluated for Cd and Pb

Levels of essential and toxic elements in Porphyra columbina and Ulva sp. from San Jorge Gulf, Patagonia Argentina

Energy Technology Data Exchange (ETDEWEB)

Perez, Adriana Angela [Catedras de Toxicologia y Quimica Legal, Biologia y Bromatologia y Nutricion, Universidad Nacional de la Patagonia San Juan Bosco, Chubut (Argentina); Farias, Silvia Sara [Comision Nacional de Energia Atomica, Gerencia de Tecnologia y Medio Ambiente, Buenos Aires (Argentina); Strobl, Analia Mabel [Catedras de Toxicologia y Quimica Legal, Biologia y Bromatologia y Nutricion, Universidad Nacional de la Patagonia San Juan Bosco, Chubut (Argentina); Perez, Laura Beatriz [Catedras de Toxicologia y Quimica Legal, Biologia y Bromatologia y Nutricion, Universidad Nacional de la Patagonia San Juan Bosco, Chubut (Argentina); Lopez, Clara Magdalena [Catedra de Toxicologia y Quimica Legal, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Pineiro, Adriana [Catedra de Toxicologia y Quimica Legal, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Roses, Otmaro [Catedra de Toxicologia y Quimica Legal, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Fajardo, Maria Angelica [Catedras de Toxicologia y Quimica Legal, Biologia y Bromatologia y Nutricion, Universidad Nacional de la Patagonia San Juan Bosco, Chubut (Argentina)]. E-mail: copipat@sinectis.com.ar

2007-04-15

Baseline concentration levels of As, B, Ca, Cd, Cr, Cu, Co, Fe, Mg, Mn, Mo, Ni, P, Pb, Se, V, and Zn were determined for Porphyra columbina and Ulva sp. collected from three locations along San Jorge Gulf, in Patagonia Argentina. Elements were quantified by inductively coupled plasma-optical emission spectrometry, with the exception of lead and cadmium in some samples which were determined by electrothermal atomic absorption spectrometry. Three stations with different exposure degree to human activities, Bahia Solano, the mouth of Arroyo La Mata stream and Punta Maqueda, were selected as sampling points. The results showed a wide range of metal retention capacity between the two studied species. Regarding the levels of pollutants found in the researched sites, Punta Maqueda seemed to be less influenced by anthropogenic activities than the other two sites except for Cd. Taking into account their toxicities seasonal variations in Pb and Cd levels were studied in both algae in Punta Maqueda. Maximum concentrations of Cd (9.8 {mu}g g{sup -1} dry wt.) were observed in P. columbina during winter, and maximum levels of Pb (0.82 {mu}g g{sup -1} dry wt.) were detected in Ulva sp. during summer. Legislative and health safety aspects were evaluated for Cd and Pb.

Toxocariasis in Carnivora from Argentinean Patagonia: Species molecular identification, hosts, and geographical distribution

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R.M. Vega

2018-04-01

Full Text Available Twenty four specimens of seven species belonging to the families Felidae, Mustelidae, and Canidae were obtained in Lanín and Nahuel Huapi National Parks from March 1996 to April 2016. Specimens were processed by necropsy in order to contribute to the knowledge of toxocariasis in wild carnivores of Argentinean Patagonia. The only Puma concolor and the seven Leopardus geoffroyi were positive for Toxocara cati. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP of the ITS-1 region from larval and adult DNA was carried out to confirm parasite species identification. This is the first molecular determination of T. cati from wild felids in Argentina and the study also fill gaps about the spatial distribution and hosts for Toxocara cati. Keywords: Toxocara cati, Puma concolor, Leopardus geoffroyi, Molecular identification, Argentina

Patagonia

DEFF Research Database (Denmark)

O'Rourke, Dara; Strand, Robert

2017-01-01

.” Specifically, this case study focuses on Patagonia’s durable water repellent (DWR) problem. DWR is a highly effective chemical treatment used to waterproof jackets (supporting the quality objective) but has by-products that are toxic and persist in the environment (undermining the sustainability objective......This article examines the tensions that arise when Patagonia simultaneously pursues sustainability and quality objectives embedded within its mission statement: “Build the best product, cause no unnecessary harm, use business to inspire and implement solutions to the environmental crisis......). This case explores the challenges Patagonia has faced and presents some creative solutions to them....

Intestinal helminth fauna of the South American sea lion Otaria flavescens and fur seal Arctocephalus australis from northern Patagonia, Argentina.

Science.gov (United States)

Hernández-Orts, J S; Montero, F E; Juan-García, A; García, N A; Crespo, E A; Raga, J A; Aznar, F J

2013-09-01

We report on the intestinal helminth fauna of 56 South American sea lions, Otaria flavescens, and 5 South American fur seals, Arctocephalus australis, from northern Patagonia, Argentina. A total of 97,325 helminth specimens were collected from sea lions. Gravid individuals were represented by 6 species of parasites: 1 digenean (Ascocotyle (Ascocotyle) patagoniensis), 1 cestode (Diphyllobothrium spp.), 3 nematodes (Uncinaria hamiltoni, Contracaecum ogmorhini s.s., Pseudoterranova cattani) and 1 acanthocephalan (Corynosoma australe). In addition, third-stage larvae of 2 nematodes (Contracaecum sp. and Anisakis sp. type I) and 3 juvenile acanthocephalans (Andracantha sp., Profilicollis chasmagnathi and Corynosoma cetaceum) were also collected. Andracantha sp., C. ogmorhini s.s. and P. chasmagnathi represent new host records. A total of 1516 helminth specimens were collected from fur seals. Gravid individuals were represented by three species of parasites, namely, Diphyllobothrium spp., C. ogmorhini s.s. and C. australe. In addition, larvae of Contracaecum sp. and P. cattani, juveniles of C. cetaceum and immature cestodes (Tetrabothriidae gen. sp.) were also collected. Corynosoma australe was the most prevalent and abundant parasite in both hosts, accounting for >90% of all specimens. Sea lions and furs seals from northern Patagonia harbour the intestinal helminth communities that could be predicted for otariids, i.e. the combination of species of the genera Corynosoma, Diphyllobothrium, Pseudoterranova, Contracaecum and, in pups, Uncinaria. Additionally, both species of otariid are apparently unsuitable hosts (i.e. non-hosts) for as many as five parasite taxa. The inclusion or exclusion of these species affects estimation of species richness at both component community (11 versus 6 species in sea lions; 7 versus 3 species in fur seals) and infracommunity (mean: 3.1 versus 2.6 in sea lions; 2.2 versus 1.7 species) levels. Information about the reproductive status of

ESTIMACIÓN DE EROSIÓN HIDRICA DE SUELOS PARA PLAN DE MANEJO DEL CAMPO FORESTAL AGUAS FRÍAS, PATAGONIA ARGENTINA

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Ana C. Dufilho

2011-12-01

Full Text Available In Argentine Patagonia there exist large extensions of lands degraded by overgrazing, this favours soil water erosion. Two million hectares are eligible for forestation (Gallo et al. 2005, with some environmental limitations that require previous studies to prepare development and sustainability proposals. The study area is located in the right margin of the Litrán River, 25 kms of its estuary in Aluminé Lake (Province of Neuquén. In this area, some Mapuche (araucanian communities carry out stock breeding (mainly goats using a migrating system. This region presents very severe Aeolian and hydrological erosion. The objective of the afforestation management plan of this land, is the design of control measures, to stop erosion, like perimeter close, afforestation and structural measures for controlling erosional gully. It is then necessary, to characterize the actual and potential erosion, that would allow to carry out with measures monitoring to implement controls and mitigation. Paper presents, pedology map by interpreting and georreferencing satellite images by a Geographical Information System. (GIS. The mapping methodology was based in Hierarchical Classification of Landforms, which is the structure of the geopedology focus for mapping soil (Zinck, 1989. The classification of actual erosion was obtained from the method of the Bureau of Land Management (USDI by visual inspection of seven aspects of erosion in surface. The estimation of the potential erosion of the floors of the forest field was carried out utilizing the Universal Soil Lost Equation (USLE and ArcGis 9,2 (ESRI, 2006 to carry out the spatial analysis, obtaining a map of annual soil loss ( tn/has/year with a spatial resolution of 30 m. The application of spatial analysis tools in the study of soil water erosion in Patagonia, Argentina contributes to the objective of defining define a program of development and adequate management, as a function of the state and degree of

Difilobotriosis humana: Un caso en área no endémica de la Argentina Human diphyllobothriosis: A case in a non-endemic area of Argentina

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Diego E. Cargnelutti

2012-02-01

Full Text Available La difilobotriosis es una parasitosis intestinal causada por la infección de cestodos del genero Diphyllobothrium. En la Argentina, la Patagonia Andina es considerada una zona endémica para esta parasitosis. La infección por Diphyllobothrium latum no ha sido previamente notificada en la provincia de Mendoza; en este trabajo comunicamos un caso de esta parasitosis que fue confirmada por el análisis de las características morfológicas de los huevos eliminados con la materia fecal de un paciente infectado. Se destaca la necesidad de información y capacitación de los profesionales de la salud en el diagnóstico y tratamiento de parasitosis no endémicas.Diphyllobothriosis is an intestinal parasitosis caused by cestodes infection of the genus Diphyllobothrium. In Argentina, the Andean Patagonia is considered an endemic area for this parasitosis. Diphyllobothrium latum infection has not been previously reported in the province of Mendoza, Argentina. We are now reporting then the first case. Diphyllobothriosis was confirmed by examination of morphologic characteristics of the eggs eliminated in the patients' feces. These results suggest the requirement of a more specific training of health workers in the diagnosis and treatment of non endemic parasitosis. We want to emphasize the need of health workers' education on diagnosis and treatment of endemic and non-endemic parasitosis.

An Unusual New Theropod with a Didactyl Manus from the Upper Cretaceous of Patagonia, Argentina

Science.gov (United States)

Apesteguía, Sebastián; Smith, Nathan D.; Juárez Valieri, Rubén; Makovicky, Peter J.

2016-01-01

Background Late Cretaceous terrestrial strata of the Neuquén Basin, northern Patagonia, Argentina have yielded a rich fauna of dinosaurs and other vertebrates. The diversity of saurischian dinosaurs is particularly high, especially in the late Cenomanian-early Turonian Huincul Formation, which has yielded specimens of rebacchisaurid and titanosaurian sauropods, and abelisaurid and carcharodontosaurid theropods. Continued sampling is adding to the known vertebrate diversity of this unit. Methodology/ Principal Findings A new, partially articulated mid-sized theropod was found in rocks from the Huincul Formation. It exhibits a unique combination of traits that distinguish it from other known theropods justifying erection of a new taxon, Gualicho shinyae gen. et sp. nov. Gualicho possesses a didactyl manus with the third digit reduced to a metacarpal splint reminiscent of tyrannosaurids, but both phylogenetic and multivariate analyses indicate that didactyly is convergent in these groups. Derived characters of the scapula, femur, and fibula supports the new theropod as the sister taxon of the nearly coeval African theropod Deltadromeus and as a neovenatorid carcharodontosaurian. A number of these features are independently present in ceratosaurs, and Gualicho exhibits an unusual mosaic of ceratosaurian and tetanuran synapomorphies distributed throughout the skeleton. Conclusions/ Significance Gualicho shinyae gen. et sp. nov. increases the known theropod diversity of the Huincul Formation and also represents the first likely neovenatorid from this unit. It is the most basal tetatanuran to exhibit common patterns of digit III reduction that evolved independently in a number of other tetanuran lineages. A close relationship with Deltadromaeus from the Kem Kem beds of Niger adds to the already considerable biogeographic similarity between the Huincul Formation and coeval rock units in North Africa. PMID:27410683

VizieR Online Data Catalog: Vela Junior (RX J0852.0-4622) HESS image (HESS+, 2018)

Science.gov (United States)

H. E. S. S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Andersson, T.; Anguener, E. O.; Arakawa, M.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernloehr, K.; Blackwell, R.; Boettcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Buechele, M.; Bulik, T.; Capasso, M.; Carr, J.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chalme-Calvet, R.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Chretien, M.; Coffaro, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; Dewilt, P.; Dirson, L.; Djannati-Atai, A.; Domainko, W.; Donath, A.; Drury, L. O'c.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Foerster, A.; Funk, S.; Fuessling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzynski, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khelifi, B.; Kieffer, M.; King, J.; Klepser, S.; Klochkov, D.; Kluzniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krueger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemiere, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; Lopez-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Mora, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Niederwanger, F.; Niemiec J.; Oakes, L.; O'Brien, P.; Odaka, H.; Oettl, S.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Paz Arribas, M.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Puehlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; de Los Reyes, R.; Richter, S.; Rieger, F.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Saito, S.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schuessler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, L.; Steenkamp, R.; Stegmann, C.; Stycz, K.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der, Walt D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Voelk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Woernlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Zywucka, N.

2018-03-01

skymap.fit: H.E.S.S. excess skymap in FITS format of the region comprising Vela Junior and its surroundings. The excess map has been corrected for the gradient of exposure and smoothed with a Gaussian function of width 0.08° to match the analysis point spread function, matching the procedure applied to derive the maps in Fig. 1. sp_stat.txt: H.E.S.S. spectral points and fit parameters for Vela Junior (H.E.S.S. data points in Fig. 3 and Tab. A.2 and H.E.S.S. spectral fit parameters in Tab. 4). The errors in this file represent statistical uncertainties at 1 sigma confidence level. The covariance matrix of the fit is also included in the format: c11 c12 c_13 c21 c22 c_23 c31 c32 c_33 where the subindices represent the following parameters of the power-law with exponential cut-off (ECPL) formula in Tab. 2: 1: flux normalization (Phi0) 2: spectral index (Gamma) 3: inverse of the cutoff energy (lambda=1/Ecut) The units for the covariance matrix are the same as for the fit parameters. Notice that, while the fit parameters section of the file shows E_cut as parameter, the fit was done in lambda=1/Ecut; hence the covariance matrix shows the values for lambda in TeV-1. sp_syst.txt: H.E.S.S. spectral points and fit parameters for Vela Junior (H.E.S.S. data points in Fig. 3 and Tab. A.2 and H.E.S.S. spectral fit parameters in Tab. 4). The errors in this file represent systematic uncertainties at 1 sigma confidence level. The integral fluxes for several energy ranges are also included. (4 data files).

Formas terminales de Hippidion (Mammalia, Perissodactyla de los yacimientos del Pleistoceno Tardio-Holoceno de la Patagonia (Argentina y Chile

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Prado, J. L.

1987-04-01

Full Text Available The present study is a revision of the terminal forms of the South-American horses coming from the archeological sites of Patagonia. They are compared with those from the Northwest of Argentine. The study also includes paleoenvironmental and cronological related aspects.El presente estudio comprende una revisión de las formas terminales de caballos sudamericanos recuperados de sitios arqueológicos de la Patagonia. Se comparan con las formas del noroeste argentino. Incluye aspectos paleoambientales y cronológicos relacionados.

Ignition probability of fine dead surface fuels in native Patagonia forests of Argentina

Energy Technology Data Exchange (ETDEWEB)

Bianchi, L.; Defosse, G. E.

2014-06-01

Aim of study: The Canadian Forest Fire Weather Index (FWI) is being implemented all over the world. This index is being adapted to the Argentinean ecosystems since the year 2000. With the objective of calibrating the Fine Fuel Moisture Code (FFMC) of the FWI system to Patagonian forests, we studied the relationship between ignition probability and fine dead surface fuel moisture content (MC) as an indicator of potential fire ignition. Area of study: The study area is located in northwestern Patagonia, Argentina, and comprised two main forest types (cypress and nire) grown under a Mediterranean climate, with a dry summer and precipitations during winter and autumn ({approx}500-800 mm per year). Material and methods: We conducted lab ignition tests fires to determine the threshold of fine dead fuel ignition at different MC levels. Moisture content of dead fine surface fuels in the field was measured every 10-15 days from November to March for three seasons. We calculated the FFMC during these seasons and correlated it with the measured MC by applying a logistic regression model. We combined the results of the ignition tests and of the regressions to suggest FFMC categories for estimating fire danger in Patagonian forests. Main results: The ignition threshold occurred at MC values of 21.5 and 25.0% for cypress and nire sites, respectively. The MC measured varied from 7.3 to 129.6%, and the calculated FFMC varied between 13.4 and 92.6. Highly significant regressions resulted when FFMC was related to MC. The ignition threshold corresponded to a FFMC = 85. We proposed to divide the FFMC scale in three fire danger categories: Low (FFMC {<=} 85), High (85 < FFMC{<=}89) and Extreme (FFMC > 89). Research highlights: Our results provide a useful tool for predicting fire danger in these ecosystems, and are a contribution to the development of the Argentinean Fire Danger Rating and a reference for similar studies in other countries where the FWI is being implemented. (Author)

GeV Detection of HESS J0632+057

Energy Technology Data Exchange (ETDEWEB)

Li, Jian; Torres, Diego F.; Wilhelmi, Emma de Oña [Institute of Space Sciences (CSIC–IEEC), Campus UAB, Carrer de Magrans s/n, E-08193 Barcelona (Spain); Cheng, K.-S. [Department of Physics, University of Hong Kong, Pokfulam Road, Hong Kong (China); Kretschmar, Peter [European Space Astronomy Centre (ESA/ESAC), Science Operations Department, Villanueva de la Cañada (Madrid) (Spain); Hou, Xian [Yunnan Observatories, Chinese Academy of Sciences, 396 Yangfangwang, Guandu District, Kunming 650216 (China); Takata, Jumpei, E-mail: jian@ice.csic.es [School of Physics, Huazhong University of Science and Technology, Wuhan 430074 (China)

2017-09-10

HESS J0632+057 is the only gamma-ray binary that has been detected at TeV energies, but not at GeV energies yet. Based on nearly nine years of Fermi Large Area Telescope (LAT) Pass 8 data, we report here on a deep search for the gamma-ray emission from HESS J0632+057 in the 0.1–300 GeV energy range. We find a previously unknown gamma-ray source, Fermi J0632.6+0548, spatially coincident with HESS J0632+057. The measured flux of Fermi J0632.6+0548 is consistent with the previous flux upper limit on HESS J0632+057 and shows variability that can be related to the HESS J0632+057 orbital phase. We propose that Fermi J0632.6+0548 is the GeV counterpart of HESS J0632+057. Considering the Very High Energy spectrum of HESS J0632+057, a possible spectral turnover above 10 GeV may exist in Fermi J0632.6+0548, as appears to be common in other established gamma-ray binaries.

LAS NORMAS JURÍDICAS Y LAS POLÍTICAS PÚBLICAS SOBRE BOSQUES CULTIVADOS EN LAS REGIONES DEL CENTRO Y DE PATAGONIA EN ARGENTINA

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C. M. MINAVERRY

2017-08-01

Full Text Available El eje central de este trabajo es analizar el nivel de desarrollo de las normas jurídicas, de las políticas públicas, y de la idoneidad de las autoridades de aplicación sobre bosques cultivados, en las regiones del Centro y de la Patagonia en Argentina. Se trata de una investigación de carácter exploratorio, donde se aplicó el método de la hermenéutica jurídica y los indicadores ambientales PER. Se puede concluir que los niveles de desarrollo normativo de las provincias no son uniformes, y que la mayoría de las normas jurídicas y de las políticas públicas tienden a establecer incentivos económicos para aprovechar el efecto del mercado, sin orientarse hacia una protección integral de los ecosistemas boscosos, y que las autoridades de aplicación en su mayoría no son técnicamente adecuadas para eso.

Characterization of leveling problems of Patagonia gamma-ray spectrometry survey, Chubut province (Argentina)

International Nuclear Information System (INIS)

Ford, Kenneth L.; Lopez, Luis E.

1998-01-01

Measuring the radioelement concentrations of the soils along traverses perpendicular to the flight line direction was performed in order to gather useful information in support of the leveling of the airborne gamma-ray spectrometer survey of Patagonia. Two sites were selected as test areas which ground and airborne spectrometric data were systematically compared to asses the nature of the leveling problems. It is suspected that variations in soil moisture may play a significant roll in the leveling variations. (author)

A widespread devonian methamorphic episode in northern Patagonia, Argentina

International Nuclear Information System (INIS)

Ostera, H.A.; Linares, E; Haller, M.J; Cagnoni, M.C.; Lopez de Luchi, M

2001-01-01

One of the greatest difficulties in Rb-Sr dating on metamorphic rocks is the lack of evidences of complete re-homogenization and the assumption of a common initial ratio for all the samples analyzed. The redistribution of parent-daughter elements and the concomitant partial or complete equilibration of the isotopic system could occur on mineral or regional size domains. This fact led to many authors to discard or disapprove the use of this method in metamorphic terranes. However, recent papers suggested that this opinion has been premature and that additional information could be obtained by the Rb-Sr method despite the difficulties that it implies (Patel et al., 1999). Many reports on well fitted Rb-Sr isochrons giving the age of metamorphism in regionally metamorphosed rocks, suggest that the Sr isotopic equilibrium can take place at different scales. This paper presents data and the Rb-Sr system behaviour from a metamorphic unit (Cushamen Formation) in the Northern Patagonia, as a contribution to elucidate the evolution of the North Patagonian Massif (au)

The early Miocene balaenid Morenocetus parvus from Patagonia (Argentina and the evolution of right whales

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Mónica R. Buono

2017-12-01

Full Text Available Balaenidae (right and bowhead whales are a key group in understanding baleen whale evolution, because they are the oldest surviving lineage of crown Mysticeti, with a fossil record that dates back ∼20 million years. However, this record is mostly Pliocene and younger, with most of the Miocene history of the clade remaining practically unknown. The earliest recognized balaenid is the early Miocene Morenocetus parvus Cabrera, 1926 from Argentina. M. parvus was originally briefly described from two incomplete crania, a mandible and some cervical vertebrae collected from the lower Miocene Gaiman Formation of Patagonia. Since then it has not been revised, thus remaining a frequently cited yet enigmatic fossil cetacean with great potential for shedding light on the early history of crown Mysticeti. Here we provide a detailed morphological description of this taxon and revisit its phylogenetic position. The phylogenetic analysis recovered the middle Miocene Peripolocetus as the earliest diverging balaenid, and Morenocetus as the sister taxon of all other balaenids. The analysis of cranial and periotic morphology of Morenocetus suggest that some of the specialized morphological traits of modern balaenids were acquired by the early Miocene and have remained essentially unchanged up to the present. Throughout balaenid evolution, morphological changes in skull arching and ventral displacement of the orbits appear to be coupled and functionally linked to mitigating a reduction of the field of vision. The body length of Morenocetus and other extinct balaenids was estimated and the evolution of body size in Balaenidae was reconstructed. Optimization of body length on our phylogeny of Balaenidae suggests that the primitive condition was a relatively small body length represented by Morenocetus, and that gigantism has been acquired independently at least twice (in Balaena mysticetus and Eubalaena spp., with the earliest occurrence of this trait in the late

The early Miocene balaenid Morenocetus parvus from Patagonia (Argentina) and the evolution of right whales

Science.gov (United States)

Cozzuol, Mario A.; Fitzgerald, Erich M.G.

2017-01-01

Balaenidae (right and bowhead whales) are a key group in understanding baleen whale evolution, because they are the oldest surviving lineage of crown Mysticeti, with a fossil record that dates back ∼20 million years. However, this record is mostly Pliocene and younger, with most of the Miocene history of the clade remaining practically unknown. The earliest recognized balaenid is the early Miocene Morenocetus parvus Cabrera, 1926 from Argentina. M. parvus was originally briefly described from two incomplete crania, a mandible and some cervical vertebrae collected from the lower Miocene Gaiman Formation of Patagonia. Since then it has not been revised, thus remaining a frequently cited yet enigmatic fossil cetacean with great potential for shedding light on the early history of crown Mysticeti. Here we provide a detailed morphological description of this taxon and revisit its phylogenetic position. The phylogenetic analysis recovered the middle Miocene Peripolocetus as the earliest diverging balaenid, and Morenocetus as the sister taxon of all other balaenids. The analysis of cranial and periotic morphology of Morenocetus suggest that some of the specialized morphological traits of modern balaenids were acquired by the early Miocene and have remained essentially unchanged up to the present. Throughout balaenid evolution, morphological changes in skull arching and ventral displacement of the orbits appear to be coupled and functionally linked to mitigating a reduction of the field of vision. The body length of Morenocetus and other extinct balaenids was estimated and the evolution of body size in Balaenidae was reconstructed. Optimization of body length on our phylogeny of Balaenidae suggests that the primitive condition was a relatively small body length represented by Morenocetus, and that gigantism has been acquired independently at least twice (in Balaena mysticetus and Eubalaena spp.), with the earliest occurrence of this trait in the late Miocene�

Variaciones glaciales durante el Holoceno en Patagonia Central, Aisén, Chile: evidencias geomorfológicas Holocene glacial variations in Central Patagonia, Aisén, Chile: geomorphological evidences

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María Mardones

2011-07-01

Full Text Available Durante el Holoceno, avances y retrocesos glaciares geomorfológicamente registrados caracterizan la Patagonia. Este artículo presenta la evolución geomorfológica y las evidencias de fluctuaciones glaciales holocénicas de una región patagónica, que servirán de referencia para el estudio de la evolución paleoclimática Postglacial del extremo sur de Sudamérica. El área de trabajo es la cuenca del río Blanco (45°30'S, en la Patagonia Central (Región de Aisén, Chile. Dataciones radiométricas de sedimentos orgánicos de morrenas terminales aportan antecedentes preliminares de dos avances glaciares: el primero, representado por la morrena frontal del lago Elizalde, arroja una edad inferior a 9.370±50 años 14C AP (10.700 a 10.480 cal. años AP, lo que cronológicamente ubica este evento glaciar en el Holoceno Temprano. Esta progresión del hielo es 100 a 200 años más antigua que aquella observada inmediatamente al sur del área de estudio, en el margen oriental del lago General Carrera (o lago Buenos Aires en Argentina y aproximadamente 100 años más joven, que la registrada en la morrena de Puerto Banderas I (lago Argentino, 50°S. Este resultado sugiere un patrón de comportamiento de los glaciares de Patagonia Central diferente a aquel observado por otros investigadores en la Región de Los Lagos (41°S y en la Región de Magallanes (54°S, donde no se registran huellas de reavances glaciares durante el Holoceno Temprano. Luego de un importante retroceso hacia el oeste, un reavance glaciar más reciente se habría producido en el valle del río Quetro (afluente del río Blanco, a una edad inferior a 2.250±40 AP (2.340 a 2.150 cal. años AP, comparable con el estadio frío del Neoglacial Medio, verificado en distintos puntos de la Patagonia. Confrontando estos resultados con registros palinológicos previamente publicados por otros autores, interpretamos que las causas de ambas fluctuaciones glaciales son variaciones regionales

Ceratopetalum (Cunoniaceae) fruits of Australasian affinity from the early Eocene Laguna del Hunco flora, Patagonia, Argentina.

Science.gov (United States)

Gandolfo, María A; Hermsen, Elizabeth J

2017-03-01

Radially symmetrical, five-winged fossil fruits from the highly diverse early Eocene Laguna del Hunco flora of Chubut Province, Patagonia, Argentina, are named, described and illustrated. The main goals are to assess the affinities of the fossils and to place them in an evolutionary, palaeoecological and biogeographic context. Specimens of fossil fruits were collected from the Tufolitas Laguna del Hunco. They were prepared, photographed and compared with similar extant and fossil fruits using published literature. Their structure was also evaluated by comparing them with that of modern Ceratopetalum (Cunoniaceae) fruits through examination of herbarium specimens. The Laguna del Hunco fossil fruits share the diagnostic features that characterize modern and fossil Ceratopetalum (symmetry, number of fruit wings, presence of a conspicuous floral nectary and overall venation pattern). The pattern of the minor wing (sepal) veins observed in the Patagonian fossil fruits is different from that of modern and previously described fossil Ceratopetalum fruits; therefore, a new fossil species is recognized. An apomorphy (absence of petals) suggests that the fossils belong within crown-group Ceratopetalum . The Patagonian fossil fruits are the oldest known record for Ceratopetalum . Because the affinities, provenance and age of the fossils are so well established, this new Ceratopetalum fossil species is an excellent candidate for use as a calibration point in divergence dating studies of the family Cunoniaceae. It represents the only record of Ceratopetalum outside Australasia, and further corroborates the biogeographic connection between the Laguna del Hunco flora and ancient and modern floras of the Australasian region. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company.

Estado del conocimiento taxonómico de la fauna de Chironomidae (Diptera: Nematocera de la Patagonia

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Mariano DONATO

2009-01-01

Full Text Available La familia Chironomidae (Diptera: Nematocera es uno de los grupos de insectos más ampliamente distribuidos y abundantes en cuerpos de agua dulce. Los representantes de esta familia pueden explotar áreas con amplios gradientes ambientales. La información que se presenta está basada en la recopilación de datos distribucionales bibliográficos, del estudio del material tipo de las especies de Chironomidae depositadas en el Natural History Museum (UK y del material de colección del Museo de La Plata (Argentina. En la Patagonia, se registran 9 subfamilias, la subfamilia monotípica Chilenomyiinae es endémica de esta área. Dentro de estas subfamilias, 53 de los 111 géneros conocidos para América del Sur están presentes en la Patagonia. Del total de géneros de la Patagonia, el 20 % es endémico y 7 de ellos muestran relaciones transantárticas. En la Patagonia, se registran 177 especies de Chironomidae, el 98% de éstas son endémicas, el 3 % son consideradas nomina dubia y el 17% requiere revisión ya que su ubicación sistemática es dudosa. Las descripciones originales de las especies patagónicas de Chironomidae están basadas principalmente sobre machos (n=58 y machos y hembras (n=43, ambas representan el 57% del total; el resto de las especies han sido descriptas con diferentes combinaciones de estadios del ciclo de desarrollo.

Mineralogical association in the zone of argillic advanced alteration in a kaolin deposit of Patagonia Argentina

International Nuclear Information System (INIS)

Rainoldi, A; Oviedo, P.; Maiza, P.; Marfil, S.

2010-01-01

This work is about the mineralogical and petrological relations of the para genetic association of advanced argillic zone in the kaolin deposit in Patagonia.This study allowed to establish the sequence of events that took place in the deposit as well as the conditions under which they were generated

Polen y vegetación en la Patagonia extraandina argentina a 45º S

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Burry, Lidia S.

2005-12-01

Full Text Available Modern pollen dispersal and deposition in relation to vegetation and environmental variables at 45° S was studied in Argentinian Patagonia east of the Andes to build a modern pollen model. This model will serve to identify modern pollen assemblages that are analog of past pollen assemblages. A west-to-east gradient of decreasing precipitation and increasing temperature determines four vegetation units: (1 grass steppe, (2 grass-bush steppe, (3 bush steppe and (4 bush-brush steppe. Pollen samples were analyzed by classification and ordination methods, and correlated to environmental variables. The steppes (a dominated by the functional type grass, (1 grass steppe, and (2 grass-bush steppe located in the more humid and cooler west end of the region were separated from the (b bush-dominated steppes (3 bush steppe and (4 bush-brush steppe occurring in the central and eastern parts of the region, where conditions are drier and warmer. Azonal communities were identified as halophytic bush steppes within different vegetation units along the west-east gradient. Environmental variables related to vegetation distribution are temperature and interannual precipitation variability associated with the precipitation gradient from the cordillera to the coast, and soil salinity in the case of azonal communities.Se investigó la relación de la dispersión-deposición del polen actual con la vegetación y con variables ambientales en la Patagonia extraandina argentina a 45° S con el fin de construir un modelo polínico actual. Este modelo servirá para identificar los conjuntos polínicos actuales que sean análogos de conjuntos polínicos fósiles. En la región hay un gradiente decreciente de precipitación y creciente de temperatura de oeste a este, que determina la existencia de diferentes unidades de vegetación: (1 estepa graminosa; (2 estepa graminosa-arbustiva; (3 estepa arbustiva y (4 estepa arbustiva-matorral. Los datos de polen de muestras de suelo

Un suelo referible al periodo calido medieval en Patagonia Austral y Tierra del Fuego (Argentina. Aspectos cronologicos y paleoclimaticos

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Favier Dubois, C. M.

2002-08-01

Full Text Available Geoarchaeological work done in Southernmost Patagonia and in the north of Tierra del Fuego, have revealed the recurrent presence of a paedogenesis interval represented by a soil of an A-AC-C profile, with a mollic epipedon, in the upper section of eolian and colluvial deposits of the late Holocene. This soil is today buried in the sites that have been analyzed, while it remains exposed in other areas of the landscape. Radiocarbon dates obtained on materials placed below it (maximum ages and those obtained by OCR (Oxidizable Carbon Ratio in the AC horizon of this soil (minimum ages, indicate the beginning of its development around the year 1000 BP. Its chronology and environmental implications suggest a relationship with the medieval climatic fluctuations called Medieval Warm Period or Medieval Optimum in Europe. This period has correlates detected in Patagonia by dendroclimatic studies.Estudios geoarqueológicos realizados en 5 localidades de Patagonia austral y norte Tierra del Fuego han revelado la recurrente presencia de un suelo de perfil A-AC-C, de epipedon mólico, en depósitos eólicos y coluviales del Holoceno tardío. Este suelo se observa sepultado en los yacimientos arqueológicos analizados, mientras que permanece expuesto en otras posiciones del paisaje. Numerosas edades máximas y mínimas obtenidas por 14C y por la técnica de OCR (Oxidizable Carbon Ratio indican el comienzo de su desarrollo hacia el 1000 AP. Su cronología e implicancias ambientales permiten vincularlo con fluctuaciones climáticas desarrolladas durante el denominado Período Cálido Medieval u Optimo Medieval Europeo, con correlatos detectados en Patagonia a través de estudios dendroclimáticos.

Panorama de la familia Asteraceae (= Compositae en la Republica Argentina An overview of the plant family Asteraceae ( = Compositae in Argentina

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Liliana Katinas

2007-07-01

Full Text Available Se presenta un panorama de la familia Asteraceae en la República Argentina , que incluye una breve historia taxonómica, datos numéricos de tribus, géneros y especies, ejemplos de endemismos y daptaciones ecológicas y una reseña sobre la hipótesis del origen de la familia en Patagonia. En la Argentina, las asteráceas representan la familia más numerosa con 227 géneros (cinco son endémicos y ca. 1400 especies (92 son adventicias y 382 son endémicas. En términos de taxones nativos, se hallan representadas en nuestro país todas las tribus de Asteraceae excepto Inuleae (sensu Bremer. Las tribus Arctoteae y Calenduleae están representadas por taxones adventicios exclusivamente y Cardueae posee sólo una especie nativa. Barnadesieae y Mutisieae son las únicas tribus con géneros endémicos de Argentina y también presentan el porcentaje más alto de géneros y especies en el país en comparación con el resto de las tribus. El mayor número de especies nativas, endémicas y no endémicas, se da en las provincias fitogeográficas Altoandina y Patagónica. La tribu más representada en número de géneros es Heliantheae, y en número de especies nativas es Senecioneae.An overview of the family Asteraceae in Argentina that includes a brief taxonomic history, numerical data of tribes, genera and species, examples of endemisms and ecological adaptations, and a discussion on the hypothesis on the origin of the family in Patagonia is given. Asteraceae is the most numerous family in Argentina , with 227 genera (five are endemic and ca. 1400 species (92 are adventitious and 382 are endemic. In relation to the native taxa, all tribes of Asteraceae occur in Argentina excepting Inuleae (sensu Bremer. Tribes Arctoteae and Calenduleae are represented exclusively by adventitious taxa, and Cardueae has only one native species. Barnadesieae and Mutisieae are the only tribes with endemic genera in Argentina and they also present the highest percentage of

Latest Pleistocene and Holocene Glacier Fluctuations in southernmost Patagonia

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Menounos, B.; Maurer, M.; Clague, J. J.; osborn, G.; Ponce, F.; Davis, P. T.; Rabassa, J.; Coronato, A.; Marr, R.

2011-12-01

Summer insolation has been proposed to explain long-term glacier fluctuations during the Holocene. If correct, the record of glacier fluctuations at high latitudes in the Southern Hemisphere should differ from that in the Northern Hemisphere. Testing this insolation hypothesis has been hampered by dating uncertainties of many Holocene glacier chronologies from Patagonia. We report on our ongoing research aimed at developing a regional glacier chronology at the southern end of the Andes north and west of Ushuaia, Argentina. We have found evidence for an advance of cirque glaciers at the end of the Pleistocene; one or locally two closely spaced moraines extend up to 2 km beyond Little Ice Age moraines. Radiocarbon dating of terrestrial macrofossils recovered from basal sediments behind two of these moraines yielded ages of 10,320 ± 25 and 10,330 ± 30 14C yr BP. These moraines may record glacier advances coeval with the Antarctic Cold Reversal; surface exposure dating of these moraines is currently in progress to test this hypothesis. We find no evidence of Holocene moraines older than 6800 14C yr BP, based on the distribution of Hudson tephra of that age. At some sites, there is evidence for an early Neoglacial advance of glaciers slightly beyond (Peru. We have documented multiple wood mats with stumps in growth position separated by till units in a 100 m section of the northeast lateral moraine at Stoppani Glacier (54.78 S, 68.98 W), 50 km west of Ushuaia. Ten radiocarbon ages on these wood mats range in age from 3510 ± 15 to 135 ± 15 14C yr BP. The mats decrease in age up-section; many overlap with published age ranges for Neoglacial advances in western Canada. Taken together, these data: a) do not support the summer insolation hypothesis for Holocene glacier fluctuations in southernmost Patagonia; b) confirm paleobotanical evidence for a warm, dry early Holocene; and c) suggest that many Neoglacial advances in southernmost Patagonia and western North America

First paleoparasitological study of micromammal coprolites from the holocene of the Somuncurá Plateau Protected Natural Area (Patagonia Argentina).

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Beltrame, María Ornela; Bellusci, Agustín; Andrade, Analía

2018-02-27

The Somuncurá Plateau is a Protected Natural Area located in the middle of the northern extra-Andean arid Patagonia. Inhabited by at least 20 small mammal species, is the place with the uppermost species richness in Patagonia. The aim of this study was to examine the parasite remains from micromammal coprolites collected in association with a bone sequence recovered at the east of the Somuncurá Plateau (site "Alero Las Lechuzas"). Coprolites came from the four temporal units previously defined: unit I (4790 ± 100 yrs. 14 C B.P.), unit II, unit III (7840 ± 120 yrs. 14 C B.P.) and unit IV. Each coprolite was processed, rehydrated, homogenized, processed by spontaneous sedimentation and examined using a light microscope. Coprolites and eggs were described, measured and photographed. Samples were positive for two nematode species: Helminthoxys caudatus Freitas, Lent & Almeida, 1937 (Oxyurida, Oxyuridae) and Trichuris spp. (Trichinellida: Trichuridae). This is the first paleoparasitological study developed for the Somuncurá Plateau Protected Area. Moreover, this is the first time that the genus Helminthoxys is reported from ancient times worldwide. Coprolites were attributed to the mountain cavy Microcavia australis (Rodentia, Caviidae).The presence of H. caudatus for the Middle Holocene of northern Patagonia contributes to the study of the history of the histricomorphs and pinworms relationships. Copyright © 2018 Elsevier B.V. All rights reserved.

A Large Accumulation of Avian Eggs from the Late Cretaceous of Patagonia (Argentina) Reveals a Novel Nesting Strategy in Mesozoic Birds

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Fernández, Mariela S.; García, Rodolfo A.; Fiorelli, Lucas; Scolaro, Alejandro; Salvador, Rodrigo B.; Cotaro, Carlos N.; Kaiser, Gary W.; Dyke, Gareth J.

2013-01-01

We report the first evidence for a nesting colony of Mesozoic birds on Gondwana: a fossil accumulation in Late Cretaceous rocks mapped and collected from within the campus of the National University of Comahue, Neuquén City, Patagonia (Argentina). Here, Cretaceous ornithothoracine birds, almost certainly Enanthiornithes, nested in an arid, shallow basinal environment among sand dunes close to an ephemeral water-course. We mapped and collected 65 complete, near-complete, and broken eggs across an area of more than 55 m2. These eggs were laid either singly, or occasionally in pairs, onto a sandy substrate. All eggs were found apparently in, or close to, their original nest site; they all occur within the same bedding plane and may represent the product of a single nesting season or a short series of nesting attempts. Although there is no evidence for nesting structures, all but one of the Comahue eggs were half-buried upright in the sand with their pointed end downwards, a position that would have exposed the pole containing the air cell and precluded egg turning. This egg position is not seen in living birds, with the exception of the basal galliform megapodes who place their eggs within mounds of vegetation or burrows. This accumulation reveals a novel nesting behaviour in Mesozoic Aves that was perhaps shared with the non-avian and phylogenetically more basal troodontid theropods. PMID:23613776

A large accumulation of avian eggs from the late cretaceous of patagonia (Argentina) reveals a novel nesting strategy in mesozoic birds.

Science.gov (United States)

Fernández, Mariela S; García, Rodolfo A; Fiorelli, Lucas; Scolaro, Alejandro; Salvador, Rodrigo B; Cotaro, Carlos N; Kaiser, Gary W; Dyke, Gareth J

2013-01-01

We report the first evidence for a nesting colony of mesozoic birds on Gondwana: a fossil accumulation in Late Cretaceous rocks mapped and collected from within the campus of the National University of Comahue, Neuquén City, Patagonia (Argentina). Here, Cretaceous ornithothoracine birds, almost certainly Enanthiornithes, nested in an arid, shallow basinal environment among sand dunes close to an ephemeral water-course. We mapped and collected 65 complete, near-complete, and broken eggs across an area of more than 55 m(2). These eggs were laid either singly, or occasionally in pairs, onto a sandy substrate. All eggs were found apparently in, or close to, their original nest site; they all occur within the same bedding plane and may represent the product of a single nesting season or a short series of nesting attempts. Although there is no evidence for nesting structures, all but one of the Comahue eggs were half-buried upright in the sand with their pointed end downwards, a position that would have exposed the pole containing the air cell and precluded egg turning. This egg position is not seen in living birds, with the exception of the basal galliform megapodes who place their eggs within mounds of vegetation or burrows. This accumulation reveals a novel nesting behaviour in Mesozoic Aves that was perhaps shared with the non-avian and phylogenetically more basal troodontid theropods.

International Uranium Resources Evaluation Project (IUREP) national favourability studies: Argentina

International Nuclear Information System (INIS)

1977-08-01

Argentina is a predominantly lowland area of 2,789,240 square kilometers. The capital is Buenos Aires. The entire length of Argentina is bordered on the west by the Andes Mountains. Tile Northwest Andes-Piedmont region consists of deep valleys containing salt basins and volcanoes, and is an earthquake zone. Patagonia, in the south, is essentially an arid region of windy plateaus and valleys. The southern Andes are narrower and lower than the northern Andes and in the extreme south contain glaciers and ice fields. The east-central plain (Pampa) of Argentina has dry and humid sectors and contains most of the population. The largest rivers are chiefly in the northeast, many having only seasonal flow. There has been extensive surface and subsurface exploration for uranium in Argentina for over 20 years. Although most of the work has been performed by the CNEA, advisors from the U.S. and from the IAEA have also taken part. Private industry has been involved, but apparently only on a small scale. In the OECD report of 1970, it was stated that 400,000 square kilometers of Argentina appear very favorable for uranium while an additional 900,000 square kilometers offer fair possibilities. Uranium exploration to date suggests that sandstones of Permian and Cretaceous ages exposed in Western Argentina in the Cordillera are very promising for discovery of new deposits. Past CNEA estimates have indicated that there is considerable hope for new discoveries in those areas where reserves are now known. In addition to the known uraniferous provinces which are indeed favorable for further exploration, there are several other large areas that warrant attention. There are, for example, in the Santa Cruz area of about 15,500 square kilometers Cretaceous and Tertiary sediments with favorable facies for uranium deposition. In the Patagonia Cordillera, Jurassic, Cretaceous, and Tertiary sediments are of interest for prospecting, These rocks contain carbonaceous material and have been

Trace elements deposition in the Tierra del Fuego region (south Patagonia) by using lichen transplants after the Puyehue-Cordón Caulle (north Patagonia) volcanic eruption in 2011.

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Conti, Marcelo Enrique; Jasan, Raquel; Finoia, Maria Grazia; Iavicoli, Ivo; Plá, Rita

2016-04-01

Lichen Usnea barbata transplants were tested as a biomonitor of atmospheric deposition in an apparently pristine environment that is Tierra del Fuego region (Patagonia, Argentina). The present survey is connected with the volcanic eruption that started in north Patagonia on June 4, 2011 from the Puyehue-Cordón Caulle volcano, Chile (north Patagonia, at 1700 km of distance of our sampling sites). Lichens were collected in September 2011 (one month of exposure) and September 2012 (1 year of exposure) in 27 sites covering the northern region of the province where trees are not present. The atmospheric deposition of 27 elements by using Neutron Activation Analysis (NAA) was determined in the collected samples. The first aim of the study was to evaluate the influence of the volcanic eruption on the regional atmospheric deposition comparing our results with baseline data we determined in U. barbata in 2006 in the same sites. The second aim was to test possible patterns of bioaccumulation between the two sampling campaigns after the volcanic eruption. With respect to 2006 baseline levels, we found significant higher levels for As, Ba, Co, Cr, Cs, Na, Sb and U in lichens collected after 1 month of exposure (first sampling campaign--2011). Between the two sampling campaigns (2011-2012) after the eruption, lichens reflected the natural contamination by volcanic ashes with significantly higher median levels of Br, Cr, Fe, K, Na, Sc, and Se. Results confirmed the very good aptitude of U. barbata to reflect the levels of elements in the environment at global scale and to reflect the volcanic emissions at distant places. Volcanic eruptions cause the emission in the atmosphere of elevated levels of particulate matter. In this regard, our findings demonstrate the importance to evaluate the metal composition of the particles to avoid possible health effects.

Origin and evolution of the Laguna Potrok Aike maar (Patagonia, Argentina)

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Gebhardt, A. C.; de Batist, M.; Niessen, F.; Anselmetti, F. S.; Ariztegui, D.; Ohlendorf, C.; Zolitschka, B.

2009-04-01

Laguna Potrok Aike, a maar lake in southern-most Patagonia, is located at about 110 m a.s.l. in the Pliocene to late Quaternary Pali Aike Volcanic Field (Santa Cruz, southern Patagonia, Argentina) at about 52°S and 70°W, some 20 km north of the Strait of Magellan and approximately 90 km west of the city of Rio Gallegos. The lake is almost circular and bowl-shaped with a 100 m deep, flat plain in its central part and an approximate diameter of 3.5 km. Steep slopes separate the central plain from the lake shoulder at about 35 m water depth. At present, strong winds permanently mix the entire water column. The closed lake basin contains a sub saline water body and has only episodic inflows with the most important episodic tributary situated on the western shore. Discharge is restricted to major snowmelt events. Laguna Potrok Aike is presently located at the boundary between the Southern Hemispheric Westerlies and the Antarctic Polar Front. The sedimentary regime is thus influenced by climatic and hydrologic conditions related to the Antarctic Circumpolar Current, the Southern Hemispheric Westerlies and sporadic outbreaks of Antarctic polar air masses. Previous studies demonstrated that closed lakes in southern South America are sensitive to variations in the evaporation/precipitation ratio and have experienced drastic lake level changes in the past causing for example the desiccation of the 75 m deep Lago Cardiel during the Late Glacial. Multiproxy environmental reconstruction of the last 16 ka documents that Laguna Potrok Aike is highly sensitive to climate change. Based on an Ar/Ar age determination, the phreatomagmatic tephra that is assumed to relate to the Potrok Aike maar eruption was formed around 770 ka. Thus Laguna Potrok Aike sediments contain almost 0.8 million years of climate history spanning several past glacial-interglacial cycles making it a unique archive for non-tropical and non-polar regions of the Southern Hemisphere. In particular, variations of

Search for cosmic ray origins by the study of supernova remnants associated with molecular clouds with HESS and test of HESS II sampling system

International Nuclear Information System (INIS)

Fiasson, A.

2008-03-01

The H.E.S.S. telescope (High energy Stereoscopic System), located in Namibia, is currently the most efficient for the observation of very high energy (VHE) gamma-ray sources. It is composed of 4 large diameter telescopes working in stereoscopic mode and allows an unequaled survey of the galactic plane at these extreme wavelengths. The H.E.S.S. experiment showed the presence of high energy particles up to 100 TeV within supernova remnant. This astrophysical objects are believed to be the main particle accelerator within the Galaxy. However, the particle nature remains unclear. This thesis presents a new observational approach in order to show hadronic particles acceleration through diffusive shock within supernova remnant. A search of supernova remnant associated with molecular cloud have been led within the HESS source catalog and the H.E.S.S. observations. An analysis of the new VHE gamma-ray source in Monoceros and its interpretation are presented. As well, the analysis and interpretation of new observations of the unidentified source HESS J1745-303 are presented. The multi-wavelength analysis of the new source HESS J1714-385, coincident with the supernova remnant CTB37A is presented. A contribution to the H.E.S.S. phase II building is also presented. This second phase consists in the building of a fifth telescope at the center of the existing system. The series tests of the new camera sampling system are reported. (author)

LA PATAGONIA ORIENTAL SEGÚN UNA REAL CÉDULA de 1570 MENOSPRECIADA POR LA HISTORIOGRAFÍA CHILENA

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MANUEL RAVEST MORA

2005-12-01

Full Text Available Versa este trabajo sobre la Real Cédula de Felipe II que, en 1570, fusionó parte de la Patagonia Oriental con la Provincia del Río de la Plata, origen de la República Argentina, donde, al parecer, supieron del documento treinta años después de finalizado el debate con Chile acerca de los derechos al extremo meridional de América. Descubierta por un diplomático chileno, que informó de ella a su Cancillería en 1876 y la mencionó en un libro publicado en 1903, ha sido sistemáticamente ignorada por los escritores chilenos. Examina este trabajo las posibles causas de ese silencio historiográfico, como también las rectificaciones que la RC introduce en la tesis clásica o fundacional de Chile, formulada a mediados del XIX por Miguel Luis Amunátegui, según la cual ese país siempre ejerció jurisdicción sobre la totalidad de la Patagonia Oriental desde 1554This work deals with a 1570 Phillip the II Decree that fused a section of Atlantic Patagonia with the Rio de la Plata Province, origin of late Argentine Republic, who, apparently, learned about it thirty years after ended the discussion held with Chile in respect the rights of each country towards the southern extreme of America. Found by a chilean diplomat, who informed his Ministry of Foreign Affairs in 1876 and wrote about the document in a book published in 1903, it has been systematically ignored by chilean scholars. The work examines the possible causes for this historiographyc silence, and the rectifications that the Royal Decree introduces in the classical chilean thesis about Patagonia, enounced by Miguel Luis Amunategui in middle XIX century, according to which that whole territory always belonged to Chile since 1554

HESS J1640–465 AND HESS J1641–463: TWO INTRIGUING TeV SOURCES IN LIGHT OF NEW FERMI-LAT OBSERVATIONS

Energy Technology Data Exchange (ETDEWEB)

Lemoine-Goumard, M.; Grondin, M.-H.; Laffon, H.; Reposeur, T. [Centre d' Études Nucléaires de Bordeaux Gradignan, IN2P3/CNRS, Université Bordeaux 1, BP120, F-33175 Gradignan Cedex (France); Acero, F.; Ballet, J., E-mail: lemoine@cenbg.in2p3.fr, E-mail: grondin@cenbg.in2p3.fr [Laboratoire AIM, CEA-IRFU/CNRS/Université Paris Diderot, Service d' Astrophysique, CEA Saclay, F-91191 Gif sur Yvette (France)

2014-10-10

We report on γ-ray analysis of the region containing the bright TeV source HESS J1640–465 and the close-by TeV source HESS J1641–463 using 64 months of observations with the Fermi Large Area Telescope (LAT). Previously only one GeV source was reported in this region and was associated with HESS J1640–465. With an increased data set and the improved sensitivity afforded by the reprocessed data (P7REP) of the LAT, we now report the detection, morphological study, and spectral analysis of two distinct sources above 100 MeV. The softest emission in this region comes from the TeV source HESS J1641–463 which is well fitted with a power law of index Γ = 2.47 ± 0.05 ± 0.06 and presents no significant γ-ray signal above 10 GeV, which contrasts with its hard spectrum at TeV energies. The Fermi-LAT spectrum of the second TeV source, HESS J1640–465 is well described by a power-law shape of index Γ = 1.99 ± 0.04 ± 0.07 that links up naturally with the spectral data points obtained by the High Energy Stereoscopic System (H.E.S.S.). These new results provide new constraints concerning the identification of these two puzzling γ-ray sources.

HESS J1640–465 AND HESS J1641–463: TWO INTRIGUING TeV SOURCES IN LIGHT OF NEW FERMI-LAT OBSERVATIONS

International Nuclear Information System (INIS)

Lemoine-Goumard, M.; Grondin, M.-H.; Laffon, H.; Reposeur, T.; Acero, F.; Ballet, J.

2014-01-01

We report on γ-ray analysis of the region containing the bright TeV source HESS J1640–465 and the close-by TeV source HESS J1641–463 using 64 months of observations with the Fermi Large Area Telescope (LAT). Previously only one GeV source was reported in this region and was associated with HESS J1640–465. With an increased data set and the improved sensitivity afforded by the reprocessed data (P7REP) of the LAT, we now report the detection, morphological study, and spectral analysis of two distinct sources above 100 MeV. The softest emission in this region comes from the TeV source HESS J1641–463 which is well fitted with a power law of index Γ = 2.47 ± 0.05 ± 0.06 and presents no significant γ-ray signal above 10 GeV, which contrasts with its hard spectrum at TeV energies. The Fermi-LAT spectrum of the second TeV source, HESS J1640–465 is well described by a power-law shape of index Γ = 1.99 ± 0.04 ± 0.07 that links up naturally with the spectral data points obtained by the High Energy Stereoscopic System (H.E.S.S.). These new results provide new constraints concerning the identification of these two puzzling γ-ray sources

Marine reptiles from the Late Cretaceous of northern Patagonia

Science.gov (United States)

Gasparini, Z.; Casadio, S.; Fernández, M.; Salgado, L.

2001-04-01

During the Campanian-Maastrichtian, Patagonia was flooded by the Atlantic and reduced to an archipelago. Several localities of northern Patagonia have yielded marine reptiles. Analysis of several assemblages suggests that the diversity and abundance of pelagic marine reptiles in northern Patagonia was higher by the end of the Cretaceous than previously thought. Several plesiosaurids, including Aristonectes parvidens and the polycotylid Sulcusuchus, and the first remains of mosasaurinae have been found. The Cretaceous marine reptile record from South America is scanty. Nevertheless, materials described here suggest that Tethyan and Weddelian forms converged in northern Patagonia, as seen with invertebrates.

Depositional Environments of Late Danian Plant Localities: Chubut Provice, Patagonia, Argentina

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Comer, E.; Slingerland, R. L.; Wilf, P.

2010-12-01

Diverse, well-preserved macroflora are observed within Cretaceous and Paleocene sediments of Chubut Province, Patagonia, Argentina. These macroflora are the most well preserved early Paleocene flora from Gondwana and add new insight into the diversity and environments of that epoch. Two major sites of fossil preservation, Palacio de los Loros and Parque Provincial Ormachea, sit near the top of the Late Danian (65.5-61.7 Ma) Salamanca Formation. Understanding the depositional history of the Salamanca is important in characterizing paleoenvironments in which these flora lived and relating these Patagonian macroflora to concurrent Paleocene flora within the Gondwanan supercontinent. During a two week field season, twenty stratigraphic sections were measured along the outcrop belt at Palacio de los Loros and Ormachea Park as well as two minor sites; Las Flores, and Rancho Grande. Photo mosaics, laser ranger data, and stratigraphic columns were merged with elevated geologic maps and imported into Fledermaus to generate a 3-D visualization of facies relationships. Rock samples were also collected and will be thin sectioned and analyzed for petrography and grain size. The Salamanca Fm. consists of 7 facies, listed here in stratigraphically ascending order: 1)Transgressive sands, 2)Wispy-bedded claystone, 3)Banco Verde, 4)White Cross bedded sandstone, 5)Accretion set siltstone, 6)Transitional silty claystone and 7)Banco Negro. Based on these facies, the Salamanca Fm. is interpreted as a marine-shelf to brackish, tide-dominated, estuarine deposit. The base of the Salamanca Fm. rests on an unconformity representing a marine flooding surface and lower sections of the Salamanca, facies 1 and 2, contain abundant glauconite and fossils indicative of a marine shelf environment. These facies give way upwards to bi-directional trough cross bedded sandstones interspersed with flaser bedded sandy siltstones (facies 3 and 4) indicating a less marine estuary with strong flow regimes

Combined U-Pb SHRIMP and Hf isotope study of the Late Paleozoic Yaminué Complex, Rio Negro Province, Argentina: Implications for the origin and evolution of the Patagonia composite terrane

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Carlos J. Chernicoff

2013-01-01

Combining geological and isotope data, as well as geophysical models, we identify the Yaminué Complex within the La Esperanza-Yaminué crustal block flanked by two other, distinct crustal blocks: the Eastern block which forms part of the Patagonia terrane sensu stricto, located in the eastern Patagonian region, and the Western block forming part of the Southern Patagonia terrane. Their origins and timing of amalgamation to form the Patagonia composite terrane are also discussed.

Cerro Bombero: registro de Hippidion saldiasi Roth, 1899 (Equidae, Perissodactyla en el Holoceno temprano de Patagonia (Santa Cruz, Argentina

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Alberdi, M. T.

2008-06-01

Full Text Available A new record of Hippidion saldiasi with new radiocarbon data referred to early Holocene (8,850 ± 80 year C-14 B.P of Patagonia is reported. Both its peculiar geographic location in a scarcely prospected zone and its radiocarbon age, provide new elements to discuss the previous hypotheses about the extinction of the horses and its relations with the human beings that inhabited the different environments of South America.Presentamos un nuevo registro de Hippidion saldiasi con datación radiocarbónica directa correspondiente al Holoceno temprano de Patagonia (8.850 ± 80 años C-14 AP. Su particular ubicación temporal y geográfica en una zona poco estudiada hasta ahora y su registro reciente, aportan nuevos elementos para discutir las hipótesis previas sobre la extinción de los caballos y su relación con los grupos humanos que colonizaron los diferentes ambientes de América del Sur.

Patagonia: tocando las fibras internas

OpenAIRE

Velasco Tafur, Ximena; Borrero Caldas, Silvio

2013-01-01

El presente caso, está enfocado en Patagonia, una compañía que desde sus inicios ha desarrollado una forma poco convencional en su estilo de hacer negocios. La gerencia de Patagonia considera que muchos errores administrativos obedecen a que las empresas formulan las mismas soluciones para todos los problemas que enfrentan. Además, desde la revolución industrial, tales soluciones han privilegiado las ganancias económicas sobre la sostenibilidad ambiental, y el planeta está pasando factura por...

Silver contamination on abiotic and biotic compartments of Nahuel Huapi National Park lakes, Patagonia, Argentina

International Nuclear Information System (INIS)

Ribeiro Guevara, Sergio; Arribere, Maria; Bubach, Debora; Vigliano, Pablo; Rizzo, Andrea; Alonso, Marcelo; Sanchez, Ricardo

2005-01-01

The Ag contents of abiotic and biotic compartments of different lakes of Nahuel Huapi National Park, Patagonia, Argentina were analyzed. The water bodies studied were lakes Nahuel Huapi, Moreno, Escondido, Espejo Chico and Traful, the latter chosen as a reference lake. The Ag concentration profiles of short sediment cores, dated by 210 Pb and 137 Cs techniques, were analyzed, as well as suspended load collected from three sites of lake Nahuel Huapi. The biota studied were the native mussel Diplodon chilensis (digestive gland and total soft tissues pooled samples) and five species of fish, two native and three introduced (liver and muscle pooled samples). Ag contents were determined by Instrumental Neutron Activation Analysis (INAA). The upper layers of the sediment cores sampled in lake Nahuel Huapi were enriched in Ag contents compared to deep layers in accumulation periods corresponding to the second half of the 20th century, but this enrichment was neither observed in the reference lake Traful, nor in lakes Espejo Chico and Escondido. Ag was enriched over background level (0.1 μg g -1 ) also in suspended load collected in lake Nahuel Huapi. Ag fluxes to sediments were computed for suspended load and enriched sediment core layers. Highest Ag fluxes, from 350 to 470 μg m -2 year -1 , were measured in Nahuel Huapi near the site where the liquid effluents of the Bariloche city sewage treatment plant are released to the lake. The spatial distribution of the other Ag fluxes suggests that this is the main source of Ag to lake Nahuel Huapi and lateral transport occurs within the water body. Ag concentrations on biota samples were consistent with these conclusions. Mussels collected in lake Nahuel Huapi showed higher Ag concentrations than in the other lakes, especially when compared to lake Traful. Ag contents in mussels were strongly associated with sediment intake, but enriched probably due to sediment grain size sorting during the intake processes. Evidence of food

Desarrollo de un proyecto agrícola en la región marginal de la Patagonia Meridional Argentina. El caso de Gobernador Gregores

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María Eugenia Cepparo de Grosso

2012-02-01

Full Text Available Santa Cruz, provincia ubicada en el extremo sur del territorio continental argentino, posee un ambiente fuertemente condicionado por la fragilidad de sus características naturales y una situación socioeconómica tradicionalmente orientada a la monoactividad ganadera en el área rural y a los servicios públicos en los centros urbanos. En ese marco, y durante la década de 1990, surgió una iniciativa apoyada por organismos del Estado y financiada por bancos provinciales para estimular un proyecto agrícola adaptado a las limitadas aptitudes agrícolas de la región. Un reducido número de agricultores, inquietos por generar actividades que diversificaran el tradicional modelo pastoril, experimentaron los dilemas de los comienzos y las crisis de un proyecto de estímulo económico en un territorio marginal. Este trabajo contribuye con una serie de reflexiones acerca de las motivaciones que justifican el estudio de pequeñas sociedades en áreas marginales; de la confrontación entre el marco conceptual de la marginalidad según los países centrales y los periféricos; y del accionar y el compromiso de los actores sociales motivados por una alternativa de desarrollo local en una localidad ubicada en el centro de la Patagonia Meridional Argentina.

Primer registro de Naupactus ruizi (Coleoptera: Curculionoidea asociado con Pinus ponderosa (Gymnospermae: Pinaceae en Patagonia

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Cecilia A. GOMEZ

2006-01-01

Full Text Available Naupactus ruizi (Brèthes es un gorgojo de rostro corto, distribuido en la Argentina y Chile, que habita en ambientes áridos asociado con vegetación xerofítica y alcanza el rango más austral entre los miembros de la tribu Naupactini. Un relevamiento de insectos y de patógenos como plagas potenciales, realizado durante el 2005 en plantaciones de Pinus spp. en la Patagonia andina argentina, resultó en el hallazgo de adultos de N. ruizi que se alimentaban de acículas de Pinus ponderosa Dougl. ex Laws. Este hallazgo es sorprendente dado que las especies de Naupactini, consumen casi exclusivamente angiospermas. Interpretamos que el cambio de huésped, habría ocurrido como consecuencia de una colonización reciente favorecida por la amplia distribución geográfica del gorgojo y su capacidad para sobrevivir en hábitats marginales, donde probablemente las plantas nativas son escasas y el nuevo huésped presenta una gran abundancia local.

Sequence stratigraphic analysis of Cenomanian greenhouse palaeosols: A case study from southern Patagonia, Argentina

Science.gov (United States)

Varela, Augusto N.; Veiga, Gonzalo D.; Poiré, Daniel G.

2012-10-01

The aim of this contribution is to analyse extrinsic (i.e., tectonics, climate and eustasy) and intrinsic (i.e., palaeotopography, palaeodrainage and relative sedimentation rates) factors that controlled palaeosol development in the Cenomanian Mata Amarilla Formation (Austral foreland basin, southwestern Patagonia, Argentina). Detailed sedimentological logs, facies analysis, pedofeatures and palaeosol horizon identification led to the definition of six pedotypes, which represent Histosols, acid sulphate Histosols, Vertisols, hydromorphic Vertisols, Inceptisols and vertic Alfisols. Small- and large-scale changes in palaeosol development were recognised throughout the units. Small-scale or high-frequency variations, identified within the middle section are represented by the lateral and vertical superimposition of Inceptisols, Vertisols and hydromorphic Vertisols. Lateral changes are interpreted as the result of intrinsic factors to the depositional systems, such as the relative position within the floodplain and the distance from the main channels, that condition the nature of parent material, the sedimentation rate and eventually the palaeotopographic position. Vertical stacking of different soil types is linked to avulsion processes and the relatively abrupt change in the distance to main channels as the system aggraded. The large-scale or low-frequency vertical variations in palaeosol type occurring in the Mata Amarilla Formation are related to long-term changes in depositional environments. The lower and upper sections of the studied logs are characterised by Histosols and acid sulphate Histosols, and few hydromorphic Vertisols associated with low-gradient coastal environments (i.e., lagoons, estuaries and distal fluvial systems). At the lower boundary of the middle section, a thick palaeosol succession composed of vertic Alfisols occurs. The rest of the middle section is characterised by Vertisols, hydromorphic Vertisols and Inceptisols occurring on distal and

U-Pb zircon constraints on the age of the Cretaceous Mata Amarilla Formation, Southern Patagonia, Argentina: Its relationship with the evolution of the Austral Basin

International Nuclear Information System (INIS)

Varela, Augusto N; Poire, Daniel G; Martin, Thomas; Gerdes, Axel; Goin, Francisco J; Gelfo, Javier N; Hoffmann, Simone

2012-01-01

Despite the abundant fossil content of the Mata Amarilla Formation (Southern Patagonia, Santa Cruz Province, Argentina), its age has always generated a considerable number of questions and debates. The chronological data provided by invertebrates, dinosaurs, fish, turtles, plesiosaurs and fossil flora are contradictory. In this work, twenty U-Pb spot analyses by laser ablation were carried out on the outer parts of the zoned zircon crystals from a tuff layer of the middle section of the Mata Amarilla Formation, yielding a U-Pb concordia age of 96.23±0.71 Ma, which corresponds to the middle Cenomanian. The deposition of the lower section of the Mata Amarilla Formation marks the onset of the foreland stage of the Austral Basin (also known as Magallanes Basin); this transition is characterized by the west-east shift of the depositional systems, which is consistent with the progradation of the Cretaceous fold-and-thrust belt. Thus, the onset of the foreland stage could have occurred between the upper Albian and lower Cenomanian, as the underlying Piedra Clavada Formation is lower Albian in age. On comparing the data obtained with information from the Ultima Esperanza Province in Chile, it can be suggested that the initiation of the closure of the Rocas Verdes Marginal Basin occurred simultaneously

Sweet cherries from the end of the world: options and constraints for fruit production systems in South Patagonia, Argentina

NARCIS (Netherlands)

Cittadini, E.D.

2007-01-01

In South Patagonia, development of the fruit production sector has been almost exclusively based on the production of sweet cherry, with an area increase from 176 ha in 1997 to 578 ha at the end of 2006. These orchards are designed as intensive systems and oriented to export markets. Even though

Review of the genus Namadytes Hesse, 1969 (Insecta: Diptera: Mydidae: Syllegomydinae

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Torsten Dikow

2014-03-01

Full Text Available The Mydidae genus Namadytes Hesse, 1969 is reviewed. It is known from five species, primarily occurring in Namibia. The study of newly available material from both Namibia and South Africa deposited in several natural history collections results in the recognition of three species and new synonymy of two, i.e., Namadytes pallidus Hesse, 1972 is a new junior synonym of Namadytes maculiventris (Hesse, 1969 and Namadytes prozeskyi Hesse, 1969: 282 is a new junior synonym of Namadytes vansoni Hesse, 1969: 280. All three species are re-described and comments on sexual dimorphism and intraspecific variation are made, a dichotomous key for their identification is presented, and illustrations and photographs are provided to support the descriptions and facilitate future identification. Distribution, occurrence in biodiversity hotspots sensu Conservation International, and seasonal incidence with associated weather and climatic data are discussed for all species. A morphological structure ventral to the halter and posterior to the metathoracic spiracle, the infra-halter sclerite, is here newly termed.

HESS J1741-302: a hidden accelerator in the Galactic plane

Science.gov (United States)

H.E.S.S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Angüner, E. O.; Arakawa, M.; Armand, C.; Arrieta, M.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bonnefoy, S.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Büchele, M.; Bulik, T.; Capasso, M.; Caroff, S.; Carosi, A.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Colafrancesco, S.; Condon, B.; Conrad, J.; Davids, I. D.; Decock, J.; Deil, C.; Devin, J.; Dewilt, P.; Dirson, L.; Djannati-Ataï, A.; Donath, A.; Drury, L. O.'c.; Dyks, J.; Edwards, T.; Egberts, K.; Emery, G.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Funk, S.; Füßling, M.; Gabici, S.; Gallant, Y. A.; Garrigoux, T.; Gaté, F.; Giavitto, G.; Glawion, D.; Glicenstein, J. F.; Gottschall, D.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holch, T. L.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khélifi, B.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lefaucheur, J.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Malyshev, D.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Nakashima, S.; De Naurois, M.; Ndiyavala, H.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poireau, V.; Prokhorov, D. A.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Rauth, R.; Reimer, A.; Reimer, O.; Renaud, M.; De Los Reyes, R.; Rieger, F.; Rinchiuso, L.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Saito, S.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Shiningayamwe, K.; Simoni, R.; Sol, H.; Spanier, F.; Spir-Jacob, M.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Steppa, C.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsirou, M.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Zorn, J.; Żywucka, N.; NANTEN Collaboration; Enokiya, R.; Fukui, Y.; Hayakawa, T.; Okuda, T.; Torii, K.; Yamamoto, H.

2018-04-01

The H.E.S.S. Collaboration has discovered a new very high energy (VHE, E > 0.1 TeV) γ-ray source, HESS J1741-302, located in the Galactic plane. Despite several attempts to constrain its nature, no plausible counterpart has been found so far at X-ray and MeV/GeV γ-ray energies, and the source remains unidentified. An analysis of 145-h of observations of HESS J1741-302 at VHEs has revealed a steady and relatively weak TeV source ( 1% of the Crab Nebula flux), with a spectral index of Γ = 2.3 ± 0.2stat ± 0.2sys, extending to energies up to 10 TeV without any clear signature of a cut-off. In a hadronic scenario, such a spectrum implies an object with particle acceleration up to energies of several hundred TeV. Contrary to most H.E.S.S. unidentified sources, the angular size of HESS J1741-302 is compatible with the H.E.S.S. point spread function at VHEs, with an extension constrained to be below 0.068° at a 99% confidence level. The γ-ray emission detected by H.E.S.S. can be explained both within a hadronic scenario, due to collisions of protons with energies of hundreds of TeV with dense molecular clouds, and in a leptonic scenario, as a relic pulsar wind nebula, possibly powered by the middle-aged (20 kyr) pulsar PSR B1737-30. A binary scenario, related to the compact radio source 1LC 358.266+0.038 found to be spatially coincident with the best fit position of HESS J1741-302, is also envisaged.

Atmospheric monitoring in H.E.S.S.

Directory of Open Access Journals (Sweden)

Hahn J.

2015-01-01

Full Text Available Instruments applying the IACT method, such as H.E.S.S. (High Energy Stereoscopic System, observe VHE (very high energy, E > 100 GeV photons indirectly, using the Earth's atmosphere as a calorimeter. In the H.E.S.S. data reconstruction, the properties of this component are estimated by Monte Carlo simulations of a yearly averaged atmosphere density profile. Deviations of the real atmospheric conditions from this assumed atmospheric model will result in a biased reconstruction of the primary gamma-ray energy and thus the resulting source spectrum. In order to keep the corresponding systematic effects to a minimum, H.E.S.S. operates a set of atmospheric monitoring devices that allows it to characterise the atmospheric conditions during data taking. This information in turn is then used in data selection. Here, a short overview with respect to their usage during source observation and a posteriori analysis data selection will be presented.

210 Pb fluxes in sediment layers sampled from Northern Patagonia lakes

International Nuclear Information System (INIS)

Ribeiro Guevara, S.; Sanchez, R.; Arribere, M.; Rizzo, A.

2003-01-01

Unsupported 210 Pb fluxes were determined from sediment core inventories in lakes located in Northern Patagonia, Argentina. Total 210 Pb, 226 Ra, associated with supported 210 Pb, and 137 Cs specific activity profiles were measured by gamma-ray spectrometry. Unsupported 210 Pb fluxes showed very low values when compared to other regions, with a 12 fold variation, ranging from 4 to 48 Bq m -2 x y -1 . The linear correlation observed between the 210 Pb fluxes and 137 Cs cumulative fluxes in sediment cores sampled from water bodies within a zone with similar precipitation demonstrated that both radioisotopes behave in the same manner in these systems concerning the processes occurred from fallout to sediment deposition, and that there are no appreciable local or regional sources of unsupported 210 Pb. Positive correlation of 210 Pb fluxes with organic matter contents of the uppermost sediment core layers was also observed. (author)

Ventajas competitivas: Una propuesta paso a paso de búsqueda y aplicación de cadena de valor adaptada a empresas aéreas. Caso Patagonia- Argentina

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María Alejandra Gazzera

2005-05-01

Full Text Available El desarrollo del proceso de búsqueda de ventajas competitivas de una empresa se puede plantear como un esfuerzo que se sigue en tres grandes líneas de actuación: la búsqueda centrada en la empresa, centrada en el entorno, y centrada en los competidores. Si bien la búsqueda de ventajas competitivas está estrechamente interrelacionada y vinculada entre las tres líneas, el presente trabajo se centrará en la primera de ellas, es decir al interior de la empresa, sin perder de vista la relación que tienen las empresas con su entorno o mercado, mediante la aplicación de la cadena de valor de Michael Porter (1985 adaptada a las empresas aéreas que operaban desde y hacia la ciudad de Neuquen, puerta de entrada a la Patagonia Argentina Es necesario destacar que no existen al presente, año 2005, estudios de este tipo en el sector mencionado en Argentina, pero en otros sectores productivos y aún en empresas aéreas de otros países, la cadena de valor ha demostrado su utilidad como tecnología de reflexión estratégica para generar valor en el cliente y para dirigir los esfuerzos de la empresa hacia la consolidación o creación de ventajas competitivas sostenibles en el tiempo.

New investigations on the origin of cosmic rays. 1. Hess experiment

International Nuclear Information System (INIS)

Degrange, B.

2005-01-01

Hess is an international experiment on astrophysics settled in altitude in Namibia and whose aim is the study of cosmic radiation sources through the indirect detection of gamma rays whose energy ranges between 100 GeV and a few TeV. Hess is composed of 4 big telescopes located at the 4 summits of a square whose sides are 120 m long. This pattern of telescopes allows the stereoscopic reconstruction of the particles showers issued from the interaction of a cosmic particle with the atmosphere and enables scientists to tell electromagnetic showers from hadronic showers which are broader and more asymmetrical. These 4 telescopes detect the Cherenkov light. Hess has been operating since december 2003. Hess has detected for the first time a binary system in our galaxy. The center of our galaxy has been examined by Hess. The spectrum measured fits a power law well and the contribution of possible neutralinos cannot be prevailing in the very low-sloped spectrum unless neutralinos have a mass greater than 7.5 TeV which is very unlikely. Hess has enabled us to show the shell pattern in the gamma mapping of the remnants of the super-nova RXJ-1713-3946. (A.C.)

U-Pb zircon constraints on the age of the Cretaceous Mata Amarilla Formation, Southern Patagonia, Argentina: its relationship with the evolution of the Austral Basin Edades U-Pb en circones de la Formación Mata Amarilla (Cretácico, Patagonia Austral, Argentina: su relación con la evoluci��n de la Cuenca Austral

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Augusto N Varela

2012-09-01

Full Text Available Despite the abundant fossil content of the Mata Amarilla Formation (Southern Patagonia, Santa Cruz Province, Argentina, its age has always generated a considerable number of questions and debates. The chronological data provided by invertebrates, dinosaurs, fish, turtles, plesiosaurs and fossil flora are contradictory. In this work, twenty U-Pb spot analyses by laser ablation were carried out on the outer parts of the zoned zircon crystals from a tuff layer of the middle section of the Mata Amarilla Formation, yielding a U-Pb concordia age of 96.23±0.71 Ma, which corresponds to the middle Cenomanian. The deposition of the lower section of the Mata Amarilla Formation marks the onset of the foreland stage of the Austral Basin (also known as Magallanes Basin; this transition is characterized by the west-east shift of the depositional systems, which is consistent with the progradation of the Cretaceous fold-and-thrust belt. Thus, the onset of the foreland stage could have occurred between the upper Albian and lower Cenomanian, as the underlying Piedra Clavada Formation is lower Albian in age. On comparing the data obtained with information from the Última Esperanza Province in Chile, it can be suggested that the initiation of the closure of the Rocas Verdes Marginal Basin occurred simultaneously.A pesar del abundante contenido fosilífero de la Formación Mata Amarilla (Patagonia Austral, Provincia de Santa Cruz, Argentina, siempre se generaron abundantes dudas y debates acerca de cuál es la edad de esta formación. Los datos cronológicos aportados por los invertebrados, los dinosaurios, peces, tortugas, plesiosaurios y flora fósil son dispares. En el presente trabajo se obtuvo una edad U-Pb concordia por la metodología de ablación láser aplicada a 20 puntos de la parte externa de circones zonados provenientes de un nivel tobáceo hallado en la sección media de la Formación Mata Amarilla, lo cual arrojó una edad de 96,23±0,71 Ma, que

ON THE PRESENCE OF PYRAMIODONTHERIUM (MAMMALIA, XENARTHRA, MEGATHERIIDAE IN THE LATE MIOCENE OF NORTHEASTERN ARGENTINA AND ITS BIOGEOGRAPHICAL IMPLICATIONS

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DIEGO BRANDONI

2009-03-01

Full Text Available The biochron of the subfamily Megatheriinae, large to very large terrestrial sloths typified by Megatherium Cuvier, in Argentina extends from the middle Miocene of Patagonia to the late Pleistocene-early Holocene. Megatheriines reached their highest diversity in the lower levels (="conglomerado osífero", late Miocene of the Ituzaingó Formation in Entre Ríos Province, northeastern Argentina. Among the four megatheriines that occur in this unit, the genera Promegatherium Ameghino, Eomegatherium Kraglievich and Pliomegatherium Kraglievich represent relatively small to medium-sized taxa. Here we describe new material assigned to Pyramiodontherium, the largest of the four genera from the same bed and comparable in size to some Quaternary species of Megatherium. Three valid species of Pyramiodontherium have been recognized, all distributed mainly in northwestern Argentina, from the late Miocene in Catamarca Province (and probably also in Tucumán Province, and the late Pliocene in La Rioja Province. The presence of this genus in northeastern Argentina extends its known paleobiogeographical distribution. 

Silver contamination on abiotic and biotic compartments of Nahuel Huapi National Park lakes, Patagonia, Argentina

Energy Technology Data Exchange (ETDEWEB)

Ribeiro Guevara, Sergio; Arribere, Maria; Bubach, Debora; Vigliano, Pablo; Rizzo, Andrea; Alonso, Marcelo; Sanchez, Ricardo

2005-01-05

The Ag contents of abiotic and biotic compartments of different lakes of Nahuel Huapi National Park, Patagonia, Argentina were analyzed. The water bodies studied were lakes Nahuel Huapi, Moreno, Escondido, Espejo Chico and Traful, the latter chosen as a reference lake. The Ag concentration profiles of short sediment cores, dated by {sup 210}Pb and {sup 137}Cs techniques, were analyzed, as well as suspended load collected from three sites of lake Nahuel Huapi. The biota studied were the native mussel Diplodon chilensis (digestive gland and total soft tissues pooled samples) and five species of fish, two native and three introduced (liver and muscle pooled samples). Ag contents were determined by Instrumental Neutron Activation Analysis (INAA). The upper layers of the sediment cores sampled in lake Nahuel Huapi were enriched in Ag contents compared to deep layers in accumulation periods corresponding to the second half of the 20th century, but this enrichment was neither observed in the reference lake Traful, nor in lakes Espejo Chico and Escondido. Ag was enriched over background level (0.1 {mu}g g{sup -1}) also in suspended load collected in lake Nahuel Huapi. Ag fluxes to sediments were computed for suspended load and enriched sediment core layers. Highest Ag fluxes, from 350 to 470 {mu}g m{sup -2} year{sup -1}, were measured in Nahuel Huapi near the site where the liquid effluents of the Bariloche city sewage treatment plant are released to the lake. The spatial distribution of the other Ag fluxes suggests that this is the main source of Ag to lake Nahuel Huapi and lateral transport occurs within the water body. Ag concentrations on biota samples were consistent with these conclusions. Mussels collected in lake Nahuel Huapi showed higher Ag concentrations than in the other lakes, especially when compared to lake Traful. Ag contents in mussels were strongly associated with sediment intake, but enriched probably due to sediment grain size sorting during the intake

Hess, Prof. Walter Rudolf

Indian Academy of Sciences (India)

Home; Fellowship. Fellow Profile. Elected: 1966 Honorary. Hess, Prof. Walter Rudolf Nobel Laureate (Medicine) - 1949. Date of birth: 17 March 1881. Date of death: 12 August 1973. YouTube; Twitter; Facebook; Blog. Academy News. IAS Logo. 29th Mid-year meeting. Posted on 19 January 2018. The 29th Mid-year meeting ...

Sedimentología e icnología de la formación río Mayer, cuenca Austral, provincia de Santa Cruz, Argentina

OpenAIRE

Richiano, Sebastián

2012-01-01

El presente trabajo de tesis doctoral se centró en el estudio sedimentológico e icnológico de las sedimentitas marinas de la Formación Río Mayer, depositada en el Cretácico inferior de la Cuenca Austral. Dicha cuenca se ubica en el extremo suroccidental de la Patagonia abarcando un sector de Sudamérica que incluye el sur de Argentina y Chile, y representa una de las más importantes cuencas productoras de hidrocarburos de Argentina. El área de estudio contempla la región entre los lagos San Ma...

The γ-ray sky seen with H.E.S.S

International Nuclear Information System (INIS)

Volpe, F.

2011-01-01

H.E.S.S. is an array of four imaging Cherenkov telescopes located in the Khomas Highlands of Namibia. It has been in operation since December 2003 and detects very-high-energy (VHE) γ-rays with energies ranging from 100 GeV to ∼ 50 TeV. Since 2004, regular observation of the Galactic Plane has yielded wind nebulae (PWN), supernova remnants (SNRs), γ-ray binaries and, more recently, a stellar cluster and molecular clouds in the vicinity of shell-type SNRs. H.E.S.S. has observed fast and intense TeV variability. Highlights of the most recent H.E.S.S. observations are presented and their implications are discussed.

Current situation of the facilities, equipments and human resources in nuclear medicine in Argentina

International Nuclear Information System (INIS)

Chiliutti, Claudia A.

2008-01-01

The current situation of nuclear medicine in Argentina, taking into account the facilities, their equipment and human resources available is presented in this paper. A review and analysis of the equipment, including technical characteristics and a survey of the professionals and technicians of the area, was carried out. In Argentina, there are 266 centers of nuclear medicine distributed all over the country. The operating licenses are granted by the Nuclear Regulatory Authority (Autoridad Regulatoria Nuclear - ARN). Forty four percent of the installed equipment are SPECT of 1 or 2 heads and 39,4 % are gamma camera. Besides, there are eleven PET operating in Argentina. There are 416 nuclear medicine physicians with individual permit for diagnostic purposes and 50% of them has also individual permit for treatment purposes. With the purpose of analyzing the regional distribution of the available resources in nuclear medicine, the country was divided into 7 geographical regions: City of Buenos Aires, Province of Buenos Aires, Pampa, Cuyo, Northeast, Northwest and Patagonia. From the analysis of the gathered information it is possible to conclude that the nuclear medicine equipment as well as the personnel present an irregular distribution, with a major concentration in the City of Buenos Aires and Province of Buenos Aires. The Northeast region presents the lowest number of Nuclear Medicine centers and the Patagonia region has the lowest number of medicine nuclear physicians with individual permits. The number of SPECT and gamma cameras is 7,3 per million of inhabitants. The information about the available resources in nuclear medicine presented in this paper and its comparison with the international information available provide elements for a better planning of the future activities in the area not only for the operators but also from the regulatory point of view. (author)

Estado del conocimiento de humedales del norte patagónico (Argentina: aspectos relevantes e importancia para la conservación de la biodiversidad regional State of the knowledge of north Patagonian wetlands (Argentina: major aspects and importance for regional biodiversity conservation

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MARÍA G PEROTTI

2005-12-01

Full Text Available Las áreas de humedal ocupan casi el 5 % del territorio de la Patagonia argentina. En la zona extrandina y el desierto patagónico estos ecosistemas son esenciales para sostener numerosas especies de fauna y flora silvestre. Además, los humedales del norte patagónico permiten el desarrollo de comunidades acuáticas complejas y constituyen el hábitat crítico de grupos de organismos como los peces y los anfibios incluidos en listados de conservación prioritaria. Estos ecosistemas tienen un funcionamiento complejo que depende estrechamente de las fluctuaciones de las variables meteorológicas y son por lo tanto muy sensibles a los efectos del cambio climático. En la actualidad el uso de la tierra, la introducción de especies y la interacción de estos aspectos con el cambio climático constituyen las variables de mayor impacto sobre estos ambientes patagónicos. En este trabajo se presenta información geográfica, geomorfológica y climática de un número de humedales del norte de la Patagonia argentina. Por otra parte, se sintetiza información sobre la flora y la distribución de peces y anfibios con el propósito de enfatizar la importancia de estos ambientes en el mantenimiento de la biodiversidad regional. Por último, se señalan los procesos que actualmente afectan a estos sistemas poniendo en evidencia la necesidad de obtención de conocimientos básicos para el diseño de planes de manejo y conservación de sus comunidades biológicasAlmost 5 % of the lansdscape of Patagonia is occupied by wetlands. In the extra-andean region and the patagonian desert, wetlands are essential for sustaining biodiversity and wildlife. Besides, North patagonian wetlands present complex aquatic communities and provide habitat for threatened species of fishes and amphibians. These ecosystems have complex dynamics mostly driven by climatic fluctuations which make them vulnerable to the effect of climate change. Nowadays, the main impact on patagonian

Sexual dimorphism in the mandible of the armadillo Chaetophractus villosus (Desmarest, 1804 (Dasypodidae from northern Patagonia, Argentina Dimorfismo sexual da mandíbula do tatu Chaetophractus villosus (Desmarest, 1804 (Dasypodidae do norte da Patagônia Argentina

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SM. Squarcia

2009-05-01

Full Text Available The aim of this study was to study the sexual dimorphism in adult Chaetophractus villosus (Desmarest, 1804, from northern Patagonia, Argentina. Eight mandibular traits were measured in 37 males and 34 females. Univariate and multivariate morphometric analysis were applied to the data set. Results showed that C. villosus was sexually dimorphic, with higher absolute values corresponding to females. The total length of the mandible was the most important variable to discriminate sexes, followed by the height at the level of the last tooth and body length. The percentages of sex discrimination were high, as they were when a new sample (17 males, 13 females was tested. Females have larger mandibles than males independently of their larger cranial size. They also showed a higher degree of correlation between variables, suggesting a more stable shape for the mandible than in males.O presente estudo examinou o dimorfismo sexual dos adultos de Chaetophractus villosus (Desmarest, 1804 do norte da Patagônia Argentina. Oito parâmetros mandibulares foram medidos em 37 machos e 34 fêmeas. Análises morfométricas univariada e multivariada foram aplicadas à série de dados. Os resultados mostraram que C. villosus apresenta dimorfismo sexual, com todos os valores absolutos mais elevados nas fêmeas. O comprimento total da mandíbula foi a variável mais importante para discriminar os sexos, seguidos pela altura no nível dos últimos dentes e pelo comprimento do corpo da mandíbula. As porcentagens de discriminação dos sexos foram elevadas, quando uma amostra nova (17 machos, 13 fêmeas foi testada. As fêmeas têm as mandíbulas maiores que os machos, independentemente de seu tamanho cranial maior. Mostraram também um grau mais elevado de correlação entre variáveis, sugerindo uma forma mais estável para a mandíbula que nos machos.

The diet of the South American sea lion (Otaria flavescens at Río Negro, Patagonia, Argentina, during the winter-spring period Dieta del lobo marino de un pelo sudamericano (Otaria flavescens en Río Negro, Patagonia, Argentina, durante el invierno y primavera

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Raimundo L. Bustos

2012-12-01

Full Text Available The South American sea lion, Otaria flavescens (Shaw, 1800 population is steadily expanding along the Patagonian coast of Argentina in the last decades. However, little is known about the feeding ecology of the species in the area. The aim of this study was to analyze the food habits of O. flavescens from 91 scats collected at Río Negro province, during the winter and spring of 2005. Fish occurred in 96% of scats containing prey remains, followed by cephalopods (26%. Raneya brasiliensis (Kaup, 1856 was the most frequent and abundant species occurring in 58.6% of samples and constituting almost 50% of fish predated. Second in importance were Porichthys porosissimus (Cuvier, 1829 and Cynoscion guatucupa (Cuvier, 1830 in terms of occurrence (%FO 20.7 and numbers (29.6% respectively. The squid Loligo gahi (d'Orbigny, 1835 was the most frequent cephalopod prey (42.1%, whereas Octopus tehuelchus (d'Orbigny, 1834 was the most abundant (77%. The higher amount and diversity of prey found in the spring in comparison with the winter season might be related to a higher feeding activity of seals or to a seasonal increase in food availability in the area.La población del lobo marino de un pelo sudamericano Otaria flavescens (Shaw, 1800 ha experimentado un crecimiento continuo en las ultimas décadas en las costas de la Patagonia Argentina. Sin embargo, poco se conoce sobre la ecología trófica de la especie en el área. El objetivo de este estudio fue analizar los hábitos alimentarios de O. flavescens a partir de 91 fecas colectadas en la provincia de Río Negro, durante el invierno y la primavera del 2005. Los peces estuvieron presentes en el 96% de las fecas que contenían remanentes presas, seguidos por los cefalópodos (26%. Raneya brasiliensis (Kaup, 1856 fue la especie mas frecuente y abundante ocurriendo en el 58.6% de las muestras y constituyendo casi el 50% de los peces predados. Le siguieron en importancia Porichthys porosissimus (Cuvier, 1829 y

The Maritime Cultural Landscape of Northern Patagonia

Science.gov (United States)

Lira, Nicolás

2017-12-01

This article is a contribution to the study of the indigenous navigation and its boats in the region of northern Patagonia. This article also aims to contribute to the understanding of indigenous navigation practices and technologies and their origins from prehistoric times to the mid-twentieth century. It presents and discusses the concept of Westerdahl's Maritime Cultural Landscape in relation to other landscape concepts. This model is applied to northern Patagonia in order to discuss if it is possible to speak of a true maritime culture in the region. For this purpose, archaeological, historical and ethnographic data are presented in an integrative and innovative methodology for the discipline. Finally, the Maritime Cultural Landscape model will allow the integration of aquatic and terrestrial landscapes as routes traveled by native inhabitants of northern Patagonia and southern Chile, and propose an important and diversified maritime, river and lake tradition.

Rehabilitation of oiled magellanic penguins (Spheniscus magellanicus) in Patagonia, Argentina

International Nuclear Information System (INIS)

Clumpner, C.J.

1993-01-01

On September 10, 1991, the International Bird Rescue Research Center (IBRRC) was contacted by Dee Boersma, professor of zoology at the University of Washington. An oil spill from an unknown source had affected large numbers of magellanic penguins (Spheniscus magellanicus) returning to breeding colonies along the coast of southern Argentina. Dr. Boersma had been studying the penguins at Punta Tombo since 1982. It wasn't unusual for some of the penguins to arrive oiled, but this year the numbers of oiled birds were up considerably. In the week of September 14 to 20, a survey of 239 kilometers of coastline (about one-third of the affected area) spotted 16,350 penguins with some degree of oiling

Discovery of the hard spectrum VHE γ-ray source HESS J1641-463

International Nuclear Information System (INIS)

Abramowski, A.; Ait Benkhali, F.

2014-10-01

This letter reports the discovery of a remarkably hard spectrum source, HESS J1641.463, by the High Energy Stereoscopic System (H.E.S.S.) in the very high energy (VHE) domain. HESS J1641.463 remained unnoticed by the usual analysis techniques due to confusion with the bright nearby source HESS J1640.465. It emerged at a significance level of 8.5 standard deviations after restricting the analysis to events with energies above 4 TeV. It shows a moderate flux level of φ (E>1 TeV)=(3.64 ± 0.44 stat ± 0.73 sys ) x 10 -13 cm -2 s -1 , corresponding to 1.8% of the Crab Nebula flux above the same energy, and a hard spectrum with a photon index of Γ=2.07±0.11 stat ±0.20 sys . It is a point-like source, although an extension up to a Gaussian width of σ=3 arcmin cannot be discounted due to uncertainties in the H.E.S.S. point-spread function. The VHE γ-ray flux of HESS J1641.463 is found to be constant over the observed period when checking time binnings from the year-by-year to the 28 minute exposure timescales. HESS J1641.463 is positionally coincident with the radio supernova remnant SNR G338.5+0.1. No X-ray candidate stands out as a clear association; however, Chandra and XMM-Newton data reveal some potential weak counterparts. Various VHE γ-ray production scenarios are discussed. If the emission from HESS J1641.463 is produced by cosmic ray protons colliding with the ambient gas, then their spectrum must extend close to 1 PeV. This object may represent a source population contributing significantly to the galactic cosmic ray flux around the knee.

The H.E.S.S. data acquisition system

CERN Document Server

Balzer, A; Gajdus, M; Göring, D; Lopatin, A; Murach, T; de Naurois, M; Schlenker, S; Schwanke, U; Stegmann, C; Wagner, P

2014-01-01

The High Energy Stereoscopic System (H.E.S.S.) is an array of five Imaging Atmospheric Cherenkov Telescopes located in the Khomas Highland in Namibia. It measures cosmic gamma-rays with very high energies (> 100 GeV) using the Earth's atmosphere as a calorimeter. The H.E.S.S. experiment has entered Phase II in September 2012 with the inauguration of a fifth telescope that is larger and more complex than the other four. The very large mirror area of 600 m(2) in comparison to the 100 m(2) of the smaller telescopes results in a lower energy threshold as well as an increased overall sensitivity of the system. Moreover, the huge effective area, due to the large mirror size, is crucial in the detection of short time scale low energy transient events. This paper will give a brief overview of the design principles of the current H.E.S.S. data acquisition and array control system. Particular emphasis is given to the new Target of Opportunity alert system that has recently been introduced to the array and allows the in...

Molecular characterization of Echinococcus isolates indicates goats as reservoir for Echinococcus canadensis G6 genotype in Neuquén, Patagonia Argentina.

Science.gov (United States)

Soriano, S V; Pierangeli, N B; Pianciola, L; Mazzeo, M; Lazzarini, L E; Saiz, M S; Kossman, A V; Bergagna, H F J; Chartier, K; Basualdo, J A

2010-12-01

Human cystic echinococcosis is a highly endemic zoonotic disease in the province of Neuquén, Patagonia Argentina, although a hydatid control programme has been carried out since 1970. Human infection due to Echinococcus canadensis (G6 genotype) is frequent in Neuquén. However, the reservoir for this species remains undetermined in a region where camels are absent. We investigated the fertility, viability and molecular epidemiology of hydatid cysts obtained from local goats, pigs and sheep in order to identify the possible reservoirs of E. canadensis (G6). We also analyzed isolates from infected dogs. A total of 67 isolates were identified by the DNA sequencing of the mitochondrial cytochrome c oxidase subunit 1 gene. Cysts from sheep (n=16), goats (n=23) and pigs (n=18) and adult worms from 10 infected dogs were analyzed. The fertility of the hydatid cysts was 78.6%; 90.4% and 94.4% for sheep, goats and pigs, respectively. We detected E. canadensis (G6) in 21 of 23 goat samples and in 1 dog isolate, E. canadensis (G7) in all the pig isolates, E. granulosus sensu stricto (G3) in 1 sheep and the G1 genotype in 15 sheep, 2 goats and 9 dog samples. The G1 haplotypes included the common sheep strain sequence and 2 microvariants of this sequence. E. granulosus sensu stricto (G3) is described for the first time in South America. We conclude that goats act as reservoir for E. canadensis (G6) in Neuquén, and that control strategies may have to be adapted to local molecular epidemiology to improve the control of parasite transmission. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

Nacionalismo territorialista en textos escolares: representaciones de la Patagonia en la dictadura militar argentina (1966-1983 Territorialist nationalism in school textbooks: representations of Patagonia in Argentinian military dictatorship (1966-1983

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Jesús Jaramillo

2012-03-01

Full Text Available Los textos escolares desde hace tiempo se han constituido en una de las fuentes primarias para el campo de la Historia de la Educación en tanto son instrumentos de socialización formal básica. Sea considerado registro escrito editorial, herramienta didáctica o registro de memoria escolar, los textos escolares instituyen - y, en ocasiones, eternizan - concepciones e intereses reflejados en sus contenidos "oficiales". Investigaciones recientes en la búsqueda de la realidad escolar han enfatizado la importancia de los mismos en la construcción de las identidades nacionales, pero también de las identidades de grupos socio-culturales, socio-étnicos y regionales. Este artículo, a partir de una indagación historiográfica sobre libros de lectura, intenta reconstruir las diferentes tramas discursivas textuales e iconográficas en que ha sido representada la Patagonia durante los periodos dictatoriales argentinos 1966-1973 y 1976-1983, en escuelas primarias de Río Negro y Neuquén. En principio, puede advertirse un conjunto de relatos de la Patagonia y sus habitantes sobre la base de tres núcleos de sentido: el de territorio indígena, desierto e inculto; el de promisión para el progreso y el turismo; y el de soberanía nacional. A través de sus argumentos daremos cuenta que los libros escolares de edición nacional con rasgos eminentemente políticos pero también étnicos y raciales fueron medios de formación y, sobre todo, dispositivos que coadyuvaron a la conformación de una línea ideológica, política y pedagógica propia del nacionalismo católico militar.School textbooks have long been taken as one of the primary sources for the field of the History of Education, since they are instruments of basic formal socializing. Either as editorial written records, as didactic tools, or as records of school memory, school textbooks institute - and sometimes crystallize - conceptions and interests reflected in their "official" contents

Variations of the Geomagnetic Field During the Holocene-Pleistocene: Relative Paleointensity Records From South-Western Argentina

Science.gov (United States)

Gogorza, C. S.

2008-05-01

I present a review of the research carried out by the Group of Geomagnetism at Universidad Nacional del Centro (Argentina) on paleointensity records from bottom sediments from three lakes: Escondido (Gogorza et al., 2004), Moreno (Gogorza et al., 2006) and El Trébol (Gogorza et al., 2007; Irurzun et al., 2008) (South-Western Argentina, 41° S, 71° 30'W). Based on these studies, we construct a first relative (RPI) stack for South-Western Argentina covering the last 21,000 14C years BP. The degree of down-core homogeneity of magnetic mineral content as well as magnetic mineral concentration and grain sizes vary between all lakes and are quantified by high-resolution rock magnetic measurements. Rock magnetic studies suggest that the main carriers of magnetization are ferrimagnetic minerals, predominantly pseudo-single domain magnetite The remanent magnetization at 20 mT (NRM20mT) was normalized using the anhysteric remanent magnetization at 20mT (ARM20mT), the saturation of the isothermal remanent at 20 mT (SIRM20mT) and the low field magnetic susceptibility {k}. Coherence function analysis indicates that the normalised records are free of environmental influences. Our paleointensity (NRM20mT/ ARM20mT) versus age curve shows a good agreement with published records from other parts of the world suggesting that, in suitable sediments, paleointensity of the geomagnetic field can give a globally coherent, dominantly dipolar signal. References Gogorza, C.S.G., Irurzun, M.A., Chaparro, M.A.E., Lirio, J.M., Nuñez, H., Bercoff, P.G., Sinito, A.M. Relative Paleointensity of the Geomagnetic Field over the last 21,000 years bp from Sediment Cores, Lake El Trébol, (Patagonia, Argentina). Earth, Planets and Space. V58(10), 1323-1332. 2006. Gogorza, C.S.G., Sinito, A.M., Lirio, J.M., Nuñez, H., Chaparro, M.A.E., Bertorello, H.R. Paleointensity Studies on Holocene-Pleistocene Sediments from Lake Escondido, Argentina. Physical of the Earth and Planetary Interiors, Elsevier, ISSN

State-of-the-art of the installations, equipments and human resources of nuclear medicine in Argentina

International Nuclear Information System (INIS)

Chiliutti, Claudia A.

2004-01-01

The current situation of nuclear medicine in Argentina, taking into account the facilities, their equipment and human resources available is presented in this paper. A review and analysis of the equipment, including technical characteristics and a survey of the professionals and technicians of the area, was carried out . In Argentina, there are 292 centers of nuclear medicine distributed all over the country. The operating licenses are granted by the Nuclear Regulatory Authority. Forty percent of the installed equipment are SPECT of 1 or 2 heads and 40 % are gamma camera. Besides, there are two PET operating in Argentina. There are 402 nuclear medicine physicians with individual permit for diagnostic purposes and 50% of them has also individual permit for treatment purposes. With the purpose of analyzing the regional distribution of the available resources in nuclear medicine, the country was divided into 7 geographical regions: City of Buenos Aires, Province of Buenos Aires, Pampeana, Cuyo, Northeast, Northwest and Patagonia. From the analysis of the gathered information it is possible to conclude that the nuclear medicine equipment as well as the personnel presents an irregular distribution, with a major concentration in the City of Buenos Aires and Province of Buenos Aires. The Northeast region presents the lowest number of Nuclear Medicine centers and the Patagonia region has the lowest number of nuclear medicine physicians with individual permits. The number of SPECT and gamma cameras is 8,65 per million of inhabitants. The information about the available resources in nuclear medicine presented in this paper and its comparison with the international available information provide elements for a better planning of the future activities in the area not only for the operators but also from the regulatory point of view. (author)

Densidad de la madera de Pinus ponderosa (Dougl. Ex Laws) en tres localidades de Argentina

OpenAIRE

JOVANOVSKI, A; JARAMILLO, M; LOGUERCIO, G; ANTEQUERA, S

2002-01-01

Se estudió el ancho de anillo, la densidad básica de la madera y su variación y la relación entre ancho de anillo y densidad en Pinus ponderosa (Dougl. Ex. Laws) creciendo en tres localidades de la Patagonia andina argentina. El ancho de anillo obtenido se corresponde con una conífera de rápido crecimiento, mientras que la densidad media es levemente menor que la de la especie creciendo en los sitios de origen en Estados Unidos. Ring-width growth, wood specific gravity and its variation, a...

U-Pb and Lu-Hf zircon geochronology of the Cañadón Asfalto Basin, Chubut, Argentina: Implications for the magmatic evolution in central Patagonia

Science.gov (United States)

Hauser, N.; Cabaleri, N. G.; Gallego, O. F.; Monferran, M. D.; Silva Nieto, D.; Armella, C.; Matteini, M.; Aparicio González, P. A.; Pimentel, M. M.; Volkheimer, W.; Reimold, W. U.

2017-10-01

The Cañadón Asfalto basin, central Chubut, Argentina, comprises a volcano-sedimentary sequence related to the opening of the Atlantic Ocean during Mesozoic times. The Lonco Trapial, Cañadón Asfalto and Cañadón Calcáreo formations are the main units related to the evolution of this basin. The Las Chacritas and Puesto Almada members are distinguished in the Cañadón Asfalto Formation. LA-HR-ICP-MS U-Pb and Lu-Hf data on zircon were obtained on these units. The Lonco Trapial Formation gave a weighted average age of 172.3 ± 1.8 Ma. A pyroclastic level from the Las Chacritas Member gave a weighted average age of 168.2 ± 2.2 Ma. Two U-Pb concordant ages of 160.3 ± 1.7 Ma on a laminated tuffite and 158.3 ± 1.3 Ma on a pyroclastic level were obtained for the Puesto Almada Member. Two maximum depositional ages constrain the sedimentary provenance areas for the basin: 1) A sample from the Sierra de la Manea range, where a controversial unit related either to the Cañadón Asfalto or to the Cañadón Calcáreo formation occurs, gave an age of 176.6 ± 1.0 Ma. Two younger zircon crystals indicate that this unit may be related to the Cañadón Calcáreo Formation. 2) A sandstone with cross-stratification from the Puesto Almada Member gave a maximum depositional age of 173.6 ± 6.4 Ma. In terms of U-Pb and Lu-Hf isotopes, two magmatic events are identified in central Patagonia: the Mamil Choique magmatic event characterized by negative εHf values around -5.0 and representing recycling during Permian times of Mesoproterozoic crust (TDM of ∼1.5 Ga), and the Cañadón Asfalto magmatic event with negative (-8.2) to positive (+4) εHf values and Meso- to Neoproterozoic TDM between 1.5 and 0.8 Ga. The younger event is characterized by three main cycles: C1 related to the Lonco Trapial magmatism, C2 to the Las Chacritas volcanism, and C3 to the Puesto Almada volcanism. These cycles are related with Marifil, Chon Aike and El Quemado formations volcanics events of

Variation in the proximate composition and fatty acid profile recovered from Argentine hake (Merluccius hubbsi waste from Patagonia

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Cretton, M.

2016-03-01

Full Text Available The fish processing operations in Patagonia produce large amounts of waste. The main fishery resource in Argentina is the Argentine hake (Merluccius hubbsi. The ports of the province of Chubut (the most important of which are Puerto Madryn, Rawson and Comodoro Rivadavia, together with Caleta Paula Port (province of Santa Cruz, in the Argentine Patagonia, capture more than 82,000 tons of hake annualy, 80% of which are of M. hubbsi, which is mostly converted into fillets. From this capture, about 2,296 tons of liver would be available for the extraction of oil. To promote the recovery and industrial use of fish oil, in the present study, we determined the variation in the proximate composition and fatty acid profile of Argentine hake waste from the ports mentioned above at different catch times. Proximate composition was determined according of the Official Methods of Analysis (AOAC. Fatty acid profile was analyzed by gas chromatography of the fatty acid methyl esters (FAMEs. A standard mixture of FAMEs was run under identical conditions to identify the compounds on the basis of their retention times. Fatty acids were quantified using heptadecanoic acid (C17:0 as internal standard. The highest lipid recovery (27.0 to 41.8% of total lipids was obtained from the liver fraction. Palmitic acid (C16:0, oleic acid (18:1 n9, docosahexaenoic acid (22:6 n3, eicosapentaenoic acid (20:5 n3 and palmitoleic acid (16:1 were the main constituents. Protein levels in viscera without livers (V-L were higher than those in the liver. The extraction of marine fish oil and the production of fish offal meal from waste from fish factories would contribute to the sustainability of the regional industry, because it would also decrease the volume of waste, with benefits to the environment.El procesamiento de pescados en Patagonia produce gran cantidad de residuos. El recurso de pesca más importante en la Argentina es la merluza argentina (Merluccius hubbsi. En Patagonia

Las especies de Leptohyphidae (Ephemeroptera de las yungas de Argentina y Bolivia: diagnosis, distribución y claves The species of Leptohyphidae (Ephemeroptera from the Argentine and Bolivian Yungas: diagnoses, distribution, and keys

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Carlos Molineri

2010-12-01

Full Text Available Se estudiaron las especies de Leptohyphidae presentes en la selva de neblina de las yungas. Se conocen, de esta región, dieciocho especies en cinco géneros, incluyendo los siguientes nuevos registros: Leptohyphes liniti Wang, Sites & McCafferty, L. maculatus Allen, L. nigripennis Molineri & Zúñiga, L. setosus Allen y Tricorythodes hiemalis Molineri para Bolivia; Leptohyphes hirsutus Allen & Roback y L. petersi Allen para Bolivia y Argentina y Tricorythodes quizeri Molineri para Argentina. Se presentan diagnosis, ilustraciones y claves para distinguir todas las especies tratadas. El estudio de la distribución de las especies presentes en las yungas reveló tres grupos: 1 un grupo formado por cinco especies restringidas a las yungas, 2 un grupo de ocho especies que extienden sus rangos a través de selvas montanas hacia el norte y 3 un grupo de tres especies también presentes en otras áreas hacia el sur (centro de Argentina y norte de la Patagonia.The species of Leptohyphidae occurring in the Yungas cloud forest are studied. Eighteen species from five genera are known from the region, including the following new country records: Leptohyphes liniti Wang, Sites & McCafferty, L. maculatus Allen, L. nigripennis Molineri & Zúñiga, L. setosus Allen, and Tricorythodes hiemalis Molineri from Bolivia; Leptohyphes hirsutus Allen & Roback and L. petersi Allen from Bolivia and Argentina; and Tricorythodes quizeri Molineri from Argentina. Diagnoses, illustrations, and keys to distinguish the treated species are presented. The study of the distribution of these species revealed three different patterns: 1 a group of five species restricted to the Yungas; 2 a group of eight species that extend their ranges toward the montane forest in the north; and 3 a group of three species also present in southern areas (central Argentina and northern Patagonia.

Primer registro de Naupactus ruizi (Coleoptera: Curculionoidea asociado con Pinus ponderosa (Gymnospermae: Pinaceae en Patagonia First record of Naupactus ruizi (Coleoptera: Curculionoidea associated to Pinus ponderosa (Gymnospermae: Pinaceae in Patagonia

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Cecilia A. Gómez

2006-07-01

Full Text Available Naupactus ruizi (Brèthes es un gorgojo de rostro corto, distribuido en la Argentina y Chile, que habita en ambientes áridos asociado con vegetación xerofítica y alcanza el rango más austral entre los miembros de la tribu Naupactini. Un relevamiento de insectos y de patógenos como plagas potenciales, realizado durante el 2005 en plantaciones de Pinus spp. en la Patagonia andina argentina, resultó en el hallazgo de adultos de N. ruizi que se alimentaban de acículas de Pinus ponderosa Dougl. ex Laws. Este hallazgo es sorprendente dado que las especies de Naupactini, consumen casi exclusivamente angiospermas. Interpretamos que el cambio de huésped, habría ocurrido como consecuencia de una colonización reciente favorecida por la amplia distribución geográfica del gorgojo y su capacidad para sobrevivir en hábitats marginales, donde probablemente las plantas nativas son escasas y el nuevo huésped presenta una gran abundancia local.Naupactus ruizi (Brèthes is a broad-nosed weevil recorded from Argentina and Chile , that inhabits arid environments with xerophitic vegetation and reaches the southern most distribution of the tribe Naupactini. A survey of potential insect pests and pathogens of plantations of Pinus spp. and other forest species, conducted during 2005 in Argentinean Patagonian Andean forestations, allowed to find N. ruizi feeding on pine needles of Pinus ponderosa Dougl. ex Laws. This finding was unexpected, since species of Naupactini consume almost exclusively angiosperms. We interpret that the new host association may represent a recent host shift, probably facilitated by the broad range of the weevil, its capacity to survive in marginal habitats where natural hosts are scarce, and the local abundance of the new host.

The upgrade of the H.E.S.S. cameras

Science.gov (United States)

Giavitto, Gianluca; Ashton, Terry; Balzer, Arnim; Berge, David; Brun, Francois; Chaminade, Thomas; Delagnes, Eric; Fontaine, Gerard; Füßling, Matthias; Giebels, Berrie; Glicenstein, Jean-Francois; Gräber, Tobias; Hinton, Jim; Jahnke, Albert; Klepser, Stefan; Kossatz, Marko; Kretzschmann, Axel; Lefranc, Valentin; Leich, Holger; Lüdecke, Hartmut; Lypova, Iryna; Manigot, Pascal; Marandon, Vincent; Moulin, Emmanuel; Naurois, Mathieu de; Nayman, Patrick; Ohm, Stefan; Penno, Marek; Ross, Duncan; Salek, David; Schade, Markus; Schwab, Thomas; Simoni, Rachel; Stegmann, Christian; Steppa, Constantin; Thornhill, Julian; Toussnel, Francois

2017-12-01

The High Energy Stereoscopic System (HESS) is an array of imaging atmospheric Cherenkov telescopes (IACTs) located in the Khomas highland in Namibia. It was built to detect Very High Energy (VHE > 100 GeV) cosmic gamma rays. Since 2003, HESS has discovered the majority of the known astrophysical VHE gamma-ray sources, opening a new observational window on the extreme non-thermal processes at work in our universe. HESS consists of four 12-m diameter Cherenkov telescopes (CT1-4), which started data taking in 2002, and a larger 28-m telescope (CT5), built in 2012, which lowers the energy threshold of the array to 30 GeV . The cameras of CT1-4 are currently undergoing an extensive upgrade, with the goals of reducing their failure rate, reducing their readout dead time and improving the overall performance of the array. The entire camera electronics has been renewed from ground-up, as well as the power, ventilation and pneumatics systems, and the control and data acquisition software. Only the PMTs and their HV supplies have been kept from the original cameras. Novel technical solutions have been introduced, which will find their way into some of the Cherenkov cameras foreseen for the next-generation Cherenkov Telescope Array (CTA) observatory. In particular, the camera readout system is the first large-scale system based on the analog memory chip NECTAr, which was designed for CTA cameras. The camera control subsystems and the control software framework also pursue an innovative design, exploiting cutting-edge hardware and software solutions which excel in performance, robustness and flexibility. The CT1 camera has been upgraded in July 2015 and is currently taking data; CT2-4 have been upgraded in fall 2016. Together they will assure continuous operation of HESS at its full sensitivity until and possibly beyond the advent of CTA. This contribution describes the design, the testing and the in-lab and on-site performance of all components of the newly upgraded HESS

An Assessment of Oil Pollution in the Coastal Zone of Patagonia, Argentina

Science.gov (United States)

Commendatore, Marta Graciela; Esteves, José Luis

2007-11-01

The Patagonian coast is considered a relatively pristine environment. However, studies conducted along coastal Patagonia have showed hydrocarbon pollution mostly concentrated at ports that have fishing, oil loading, general merchant, and/or tourist activities. A high value of total aliphatic hydrocarbons (TAH) was found at the Rawson fishing port (741 μg/g dw). In other ports with and without petroleum-related activities, hydrocarbon values were approximately 100 μg/g dw. The highest values for TAH and total aromatic hydrocarbons (TArH) were found in Faro Aristizábal, north of San Jorge gulf (1304 and 737 μg/g dw, respectively). This is very likely the result of petroleum-related activities at the Comodoro Rivadavia, Caleta Cordova, and Caleta Olivia ports located within this gulf. In other coastal areas away from potential anthropogenic sources, hydrocarbon values were less than 2 and 3 μg/g dw for TAH and TArH, respectively. This review of published and unpublished information suggests that ports are important oil pollution sources in the Patagonian coast. More detailed studies are needed to evaluate the area affected by port activities, to understand the mechanisms of hydrocarbon distribution in surrounding environments, and to assess bioaccumulation in marine organisms. Despite that some regulations exist to control oil pollution derived from port and docked vessel activities, new and stricter management guidelines should be implemented.

Sapling growth and crown expansion in canopy gaps of Nothofagus pumilio (lenga) forests in Chubut, Patagonia, Argentina

Energy Technology Data Exchange (ETDEWEB)

Lopez Bernal, P. M.; Defosse, G. E.; Quinteros, C. P.; Bava, J. O.

2012-07-01

In the province of Chubut in Patagonia, Argentina, Nothofagus pumilio forests (locally known as lenga), are managed through selective cuts, which imply the opening of canopy gaps. This management scheme is carried out without taking into consideration the changes of sapling requirements through either a cutting cycle or the precipitation gradient in which these forests thrive. To analyze these changes, we inferred the facilitation-competition balance between the canopy and regeneration, studying the effects of precipitation levels, gap size and gap age on saplings growth in height on 45 canopy gaps artificially created between 1960 and 1993. Results showed that during the first 20 years since gap opening, growth of regeneration is determined by light availability in mesic sites and by water availability in xeric sites. However, differences due to precipitation levels gradually decrease over time. Moreover, in the period between 20 and 35 years after gap opening, in both mesic and xeric sites, growth is limited by light availability. This indicates that in xeric sites, sapling growth requirements shift from a water-dependent situation to a light-dependent situation. The average closing rate of gaps due to lateral growth of bordering trees is high enough so that within the proposed gap size range, gap healing can occur before regeneration reaches the upper stratum. Consequently, in mesic sites gap opening can be done by a single operation that generates gaps with diameters of approximately twice the average height of the canopy (D/H). While in xeric environments, lenga seedling establishment and initial growth require the cover of small gaps, but advanced regeneration requires bigger gaps to reach the canopy. For this reason, gaps should be opened in two stages: the first gaps should be opened with a D/H between 0.8 and 1, and after a cutting cycle of 35 years, these openings should be enlarged to a D/H between 1.5 and 2. The close relationship maintained between the

Cultural Transmission of Traditional Knowledge in two populations of North-western Patagonia

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Lozada Mariana

2008-12-01

Full Text Available Abstract Background In the present study we have investigated the cultural transmission of two types of traditional plant knowledge in two communities of North-western Patagonia, Argentina. In the Pilcaniyeu community, we studied the transmission of traditional knowledge related to horticultural practices in home-gardens, greenhouses and gardens; while in the community of Cuyin Manzano, we studied wild plant gathering customs. Methods Ethnobotanical fieldwork was conducted by means of semi-structured interviews, in which we investigated which plants are used, at what life history phase was learned, modes of transmission and who the principal transmitters were in childhood and adulthood. In both communities, each of this three aspects related to cultural transmission were categorized and the frequencies of each category were obtained. The total number of species recorded in each community was also calculated. Frequencies were analyzed with the Chi-square test of independence. Results and discussion In both communities, transmission of traditional plant knowledge begins at an early age, as a family custom, in which women play a predominant role. Wild plant use and horticultural knowledge continue to be learned during adulthood. This was particularly registered associated with horticultural learning, which receives greater influence from extension agents who are introducing new practices and technology. This outside influence, which implies novelty, could imply syncretism but also traditional knowledge loss. Conclusion Given the remarkable acculturation processes occurring at present in rural communities of Northwestern Patagonia, it might be of vital importance to document traditional knowledge of ancient practices. Moreover, it could be interesting to share our results with both populations in order to encourage participatory activities within the communities which could enhance traditional knowledge horizontal transmission, particularly among

Probing the local environment of the supernova remnant HESS J1731-347 with CO and CS observations

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Maxted, N.; Burton, M.; Braiding, C.; Rowell, G.; Sano, H.; Voisin, F.; Capasso, M.; Pühlhofer, G.; Fukui, Y.

2018-02-01

The shell-type supernova remnant HESS J1731 - 347 emits TeV gamma-rays, and is a key object for the study of the cosmic ray acceleration potential of supernova remnants. We use 0.5-1 arcmin Mopra CO/CS(1-0) data in conjunction with H I data to calculate column densities towards the HESS J1731 - 347 region. We trace gas within at least four Galactic arms, typically tracing total (atomic+molecular) line-of-sight H column densities of 2-3× 1022 cm-2. Assuming standard X-factor values and that most of the H I/CO emission seen towards HESS J1731 - 347 is on the near-side of the Galaxy, X-ray absorption column densities are consistent with H I+CO-derived column densities foreground to, but not beyond, the Scutum-Crux Galactic arm, suggesting a kinematic distance of ˜3.2 kpc for HESS J1731 - 347. At this kinematic distance, we also find dense, infrared-dark gas traced by CS(1-0) emission coincident with the north of HESS J1731 - 347, the nearby H II region G353.43-0.37 and the nearby unidentified gamma-ray source HESS J1729 - 345. This dense gas lends weight to the idea that HESS J1729 - 345 and HESS J1731 - 347 are connected, perhaps via escaping cosmic-rays.

Patagonia: nature and territories

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Alejandro Fabián Schweitzer

2014-12-01

This paper analyzes the place occupied by Patagonia in today’s fin de siècle scenario of commodities, hegemony crisis and multi-polar world emergence concurring with the convergence of consumerist guidelines, all of which would apparently lead to an in-depth socio-ecological crisis as well as to an accelerated dispute over nature and territory sense.

Paleoecología: el uso de los quironómidos fósiles (Diptera: Chironomidae en reconstrucciones paleoambientales durante el Cuaternario en la Patagonia Paleoecology: the use of fossil chironomids (Diptera: Chironomidae for paleoenvironmental reconstructions in Patagonia

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Julieta Massaferro

2009-06-01

Full Text Available Entre los indicadores biológicos lacustres más utilizados en las reconstrucciones ambientales, se encuentran el polen, los ostrácodos y las diatomeas, y entre los insectos, los coleópteros y los quironómidos. Este grupo ha cobrado gran importancia en los últimos tiempos, debido a los resultados prometedores que se han obtenido en reconstrucciones climáticas realizadas en América del Norte y Europa. En América del Sur, el uso de los quironómidos fósiles en estudios cuaternarios es relativamente limitado, principalmente por su escaso conocimiento taxonómico regional. La mayor parte de estos estudios fueron realizados en lagos glaciares patagónicos de Argentina y Chile. Las larvas de quironómidos constituyen una valiosa herramienta paleolimnológica, por ser un grupo de organismos altamente sensible a cambios ambientales, tanto naturales como artificiales. Además, es un grupo de insectos ampliamente distribuido y con una abundancia y diversidad relativamente altas. Sus cápsulas cefálicas se preservan en los sedimentos lacustres y poseen caracteres importantes que permiten identificar géneros y muchas veces especies. El estudio de los ensambles de quironómidos en sedimentos lacustres puede ser utilizado con distintos objetivos, por ejemplo, para estudios de eutrofización, ya que responden rápidamente a cambios en la concentración de nutrientes, materia orgánica y otros elementos, como metales pesados. No obstante, uno de los potenciales más importantes de este grupo de insectos es su sensibilidad a los cambios de temperatura, por este motivo, la aplicación más importante de su estudio en sedimentos se centra en las reconstrucciones climáticas. Esta contribución es una síntesis de los resultados de los trabajos publicados en la Patagonia argentina y chilena, sobre la base del uso de los quironómidos fósiles en reconstrucciones paleoambientales.Pollen, ostracods, diatoms and insects such as beetles and chironomids are

Sedimentology and paleoenvironments of the Las Chacritas carbonate paleolake, Cañadón Asfalto Formation (Jurassic), Patagonia, Argentina

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Cabaleri, Nora G.; Benavente, Cecilia A.

2013-02-01

The Las Chacritas Member is the lower part of the Cañadón Asfalto Formation (Jurassic). The unit is a completely continental limestone succession with volcanic contributions that were deposited during the development of the Cañadón Asfalto Rift Basin (Chubut province, Patagonia, Argentina). A detailed sedimentological analysis was performed in the Fossati depocenter to determine the paleoenvironments that developed in the context of this rift. The Las Chacritas Member represents a carbonate paleolake system with ramp-shaped margins associated with wetlands that were eventually affected by subaerial exposure and pedogenesis. This process is represented by three main subenvironments: a) a lacustrine setting sensu stricto (lacustrine limestone facies association), represented by Mudstones/Wackestones containing porifera spicules (F1), Intraclastic packstones (F6) and Tabular stromatolites (F10) in which deposition and diagenesis were entirely subaqueous; b) a palustrine setting (palustrine limestone facies association) containing Microbial Mudstones (F2), Intraclastic sandy packstone with ostracode remains (F3), Oncolitic packstone (F5), Brecciated limestone (F7) and Nodular-Mottled limestone (F8) representing shallow marginal areas affected by groundwater fluctuations and minor subaerial exposure; and c) a pedogenic paleoenvironment (pedogenic limestone facies association) including Intraclastic limestone (F4) and Packstones containing Microcodium (F9) facies displaying the major features of subaerial exposure, pedogenic diagenesis and the development of paleosols. The fluvial-palustrine-lacustrine succession shows a general shallow upward trend in which contraction-expansion cycles are represented (delimited by exposure and surface erosion). The variations in the successive formations reflect the responses to fluctuations in a combination of two major controls, the tectonic and local climatic variables. The predominance of the palustrine facies associations was

Uplift of quaternary shorelines in eastern Patagonia: Darwin revisited

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Pedoja, Kevin; Regard, Vincent; Husson, Laurent; Martinod, Joseph; Guillaume, Benjamin; Fucks, Enrique; Iglesias, Maximiliano; Weill, Pierre

2011-04-01

During his journey on the Beagle, Darwin observed the uniformity in the elevation of coastal Eastern Patagonia along more than 2000 km. More than one century later, the sequences of Quaternary shorelines of eastern Patagonia have been described and their deposits dated but not yet interpreted in terms of geodynamics. Consequently, we i) mapped the repartition of the Quaternary coastal sequences in Argentinean Patagonia, ii) secured accurate altitudes of shoreline angles associated with erosional morphologies (i.e. marine terraces and notches), iii) took into account previous chrono-stratigraphical interpretations in order to calculate mean uplift rates since ~ 440 ka (MIS 11) and proposed age ranges for the higher and older features (up to ~ 180 m), and iv) focused on the Last Interglacial Maximum terrace (MIS 5e) as the best constrained marine terrace (in terms of age and altitude) in order to use it as a tectonic benchmark to quantify uplift rates along the entire passive margin of Eastern South America. Our results show that the eastern Patagonia uplift is constant through time and twice the uplift of the rest of the South American margin. We suggest that the enhanced uplift along the eastern Patagonian coast that interested Darwin during his journey around South America on the Beagle could originate from the subduction of the Chile ridge and the associated dynamic uplift.

Wszystko o Ewie. Eva Hesse i postminimalistyczna ironia romantyczna

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Szymański, Wojciech

2014-03-01

Full Text Available Artykuł jest propozycją interpretacyjną twórczości Evy Hesse w kontekście ironii romantycznej. Punkt wyjścia rozważań stanowi jeden z tekstów autorstwa Arthura Danto, w którym amerykański filozof dokonuje pozytywnego przewartościowania prac artystki i odczytuje je jako zabarwione sporym poczuciem humoru połączenie dwóch – nieprzystających na pierwszy rzut oka – tradycji sztuki amerykańskiej XX wieku: abstrakcyjnego ekspresjonizmu i minimalizmu. To, co Danto znajduje zabawnym, autor artykułu uznaje za cechę ironii romantycznej, którą to postawę przypisuje Evie Hesse. W drugiej części artykułu przedstawione zostały dwa konkurencyjne stanowiska interpretacyjne dzieła Evy Hesse: Roberta Pincus-Wittena i Lucy R. Lippard, które jednak, używając pojęcia ironii romantycznej, można uzgodnić, wskazując przy tym na pomijany dotychczas, aczkolwiek istotny, ironiczny aspekt twórczości amerykańskiej artystki.

Oceanography of the Chilean Patagonia

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Pantoja, Silvio; Luis Iriarte, José; Daneri, Giovanni

2011-03-01

Chilean Patagonia is one of the most extended fjord regions in the world that covers nearly 240,000 km 2 with an extremely complex coastline and topography in one of the least densely populated areas of the country (1-8 inhabitants every 10 km 2). In recent years, the area has been undergoing somewhat intense pressure since several commercial projects in hydroelectricity, tourism, and commercial salmon and mytilid cultures have been developed, or are in progress. Concomitantly, several large research programs have been devised to study the physical, chemical, and biological environment of Patagonia, such as the CIMAR FIORDO, and recently COPAS Sur-Austral based at Universidad de Concepcion, that attempts to close the bridge between oceanographic knowledge and its use by society. In this introductory article we summarize the collection of papers comprising this Special Issue of Continental Shelf Research. These papers deal with aspects of regional oceanography and geology, inorganic and organic geochemistry, ecology of pelagic and benthic organisms, and past changes in productivity.

Patagonia, Land of Nomads: A Glance at a Territory Shaped by Displacement

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Pablo Chiuminatto

2016-05-01

Full Text Available By the end of the nineteenth century, as global voyages became popular, and transcontinental empires settled, remote corners of the third world such as Patagonia began to be explored and became the subject of European travel literatures. The opening of this region to the global scenario produced profound transformations in its territorial conformation, poetic imaginary, and local culture. As Patagonia became a land of travellers, local nomads which had inhabited this land for centuries became extinguished. The historical context of this re-shaping is conceptualised in literary theory through notions such as nomadism, elaborated by Gilles Deleuze and its aesthetical counterpart, geo-poetics, by Kenneth White. The travel literature about Patagonia, such as that produced by Charles Darwin, Lady Florence Dixie, and Bruce Chatwin, depicts the difficulties these travellers faced in trying to endow their writings of adequate descriptions and images. Instead, they recurred to images from their homeland, and thus created an imaginary of Patagonia through displacement: their own, and that of images brought by themselves to this land. When Chilean poets like Gabriela Mistral and Pablo Neruda begun to write about Patagonia, they found it already populated by strange images, shaped indeed, by nomads, travellers and dis-located identities.

All about Eve. Eva Hesse and the Post-Minimalist Romantic Irony

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Szymański, Wojciech

2014-03-01

Full Text Available The article employs the category of Romantic irony for an interpretation of Eva Hesse's work. It takes as its starting point one of Arthur Danto's texts, where the American philosopher makes a positive re-evaluation of the artist's work, and reads it as a largely humorous combination of two – seemingly incongruent – traditions of American art of the 20thcentury: Abstract Expressionism and Minimalism. Features that Danto finds humorous, the author of the present article considers exemplary of Romantic irony, an approach that he finds in Eva Hesse's oeuvre. In the second part of the article, two competing interpretations of Eva Hesse's work are presented: Robert Pincus-Witten's and Lucy R. Lippard's. However, with the use of the notion of Romantic irony their standpoints can be reconciled, with a simultaneous indication of a previously dismissed, yet crucial, ironic aspect of the work of the American artist.

Do coastal fronts influence bioerosion patterns along Patagonia? Late Quaternary ichnological tools from Golfo San Jorge

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Richiano, Sebastián; Aguirre, Marina; Castellanos, Ignacio; Davies, Karen; Farinati, Ester

2017-12-01

Late Quaternary marine molluscan skeletal concentrations from Argentina constitute a remarkable record of variations in palaeoceanographical conditions during interglacial times (mainly ca. 125 ka to present). Particularly, the Golfo San Jorge coastal area represents an extraordinary geographical zone to target from different points of view, mainly due to its linkage between northern and southern Patagonia, characterized by particular and contrasting physico-chemical conditions with direct consequences for littoral marine communities, determining their composition and structure. Among varied biological activities controlled by different environmental factors (i.e., substrate nature, sedimentation rates, water depth, sea surface temperature, salinity, nutrients-productivity), bioerosion traces can provide palaeoenvironmental evidence with important implications for palaeoclimate interpretations. In addition, the application of bioerosion patterns regionally and through time is a recent valuable worthy palaeoenvironmental tool not as yet developed for Patagonia. We attempted to characterize, qualitatively/semiquantitatively, the ichnotaxonomic composition of the coastal area of northern Golfo San Jorge since the Late Pleistocene; to compare results with those obtained for other geographical areas along Patagonia and the Bonaerensian coastal sectors; lastly, to evaluate its palaeoenvironmental/palaeoclimatic significance in a clue area in terms of circulation patterns near the Southern Ocean climatic pump. At Bustamante (Northern Patagonia Frontal System) Domichnia traces were dominant during the Late Pleistocene while Praedichnia in the mid-Holocene. Bustamante exhibits the highest ichnodiversity for the whole Argentinean coastal area. Ichnodiversity is not strongly different between Late Pleistocene and mid-Holocene interglacials and compared to present; however, the relative abundance of some ichnotaxa (e.g., Oichnus, Iramena, Pennatichnus, at Camarones; Oichnus

HESS J1640-465 - an exceptionally luminous TeV γ-ray supernova remnant

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Abramowski, A.; Aharonian, F.; Benkhali, F. Ait; Akhperjanian, A. G.; Angüner, E.; Anton, G.; Balenderan, S.; Balzer, A.; Barnacka, A.; Becherini, Y.; Becker Tjus, J.; Bernlöhr, K.; Birsin, E.; Bissaldi, E.; Biteau, J.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Brucker, J.; Brun, F.; Brun, P.; Bulik, T.; Carrigan, S.; Casanova, S.; Cerruti, M.; Chadwick, P. M.; Chalme-Calvet, R.; Chaves, R. C. G.; Cheesebrough, A.; Chrétien, M.; Colafrancesco, S.; Cologna, G.; Conrad, J.; Couturier, C.; Cui, Y.; Dalton, M.; Daniel, M. K.; Davids, I. D.; Degrange, B.; Deil, C.; deWilt, P.; Dickinson, H. J.; Djannati-Ataï, A.; Domainko, W.; Drury, L. O'C.; Dubus, G.; Dutson, K.; Dyks, J.; Dyrda, M.; Edwards, T.; Egberts, K.; Eger, P.; Espigat, P.; Farnier, C.; Fegan, S.; Feinstein, F.; Fernandes, M. V.; Fernandez, D.; Fiasson, A.; Fontaine, G.; Förster, A.; Füßling, M.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Grondin, M.-H.; Grudzińska, M.; Häffner, S.; Hahn, J.; Harris, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hillert, A.; Hinton, J. A.; Hofmann, W.; Hofverberg, P.; Holler, M.; Horns, D.; Jacholkowska, A.; Jahn, C.; Jamrozy, M.; Janiak, M.; Jankowsky, F.; Jung, I.; Kastendieck, M. A.; Katarzyński, K.; Katz, U.; Kaufmann, S.; Khélifi, B.; Kieffer, M.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kneiske, T.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Krayzel, F.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lefaucheur, J.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Lennarz, D.; Lohse, T.; Lopatin, A.; Lu, C.-C.; Marandon, V.; Marcowith, A.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; McComb, T. J. L.; Méhault, J.; Meintjes, P. J.; Menzler, U.; Meyer, M.; Moderski, R.; Mohamed, M.; Moulin, E.; Murach, T.; Naumann, C. L.; de Naurois, M.; Niemiec, J.; Nolan, S. J.; Oakes, L.; Ohm, S.; Wilhelmi, E. de Oña; Opitz, B.; Ostrowski, M.; Oya, I.; Panter, M.; Parsons, R. D.; Arribas, M. Paz; Pekeur, N. W.; Pelletier, G.; Perez, J.; Petrucci, P.-O.; Peyaud, B.; Pita, S.; Poon, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Raue, M.; Reimer, A.; Reimer, O.; Renaud, M.; Reyes, R. de los; Rieger, F.; Rob, L.; Romoli, C.; Rosier-Lees, S.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Sanchez, D. A.; Santangelo, A.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwarzburg, S.; Schwemmer, S.; Sol, H.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stinzing, F.; Stycz, K.; Sushch, I.; Szostek, A.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tluczykont, M.; Trichard, C.; Valerius, K.; van Eldik, C.; van Soelen, B.; Vasileiadis, G.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Völk, H. J.; Volpe, F.; Vorster, M.; Vuillaume, T.; Wagner, S. J.; Wagner, P.; Ward, M.; Weidinger, M.; Weitzel, Q.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Zabalza, V.; Zacharias, M.; Zajczyk, A.; Zdziarski, A. A.; Zech, A.; Zechlin, H.-S.

2014-04-01

The results of follow-up observations of the TeV γ-ray source HESS J1640-465 from 2004 to 2011 with the High Energy Stereoscopic System (HESS) are reported in this work. The spectrum is well described by an exponential cut-off power law with photon index Γ = 2.11 ± 0.09stat ± 0.10sys, and a cut-off energy of E_c = 6.0^{+2.0}_{-1.2} TeV. The TeV emission is significantly extended and overlaps with the northwestern part of the shell of the SNR G338.3-0.0. The new HESS results, a re-analysis of archival XMM-Newton data and multiwavelength observations suggest that a significant part of the γ-ray emission from HESS J1640-465 originates in the supernova remnant shell. In a hadronic scenario, as suggested by the smooth connection of the GeV and TeV spectra, the product of total proton energy and mean target density could be as high as WpnH ˜ 4 × 1052(d/10kpc)2 erg cm-3.

Characterization of black volcanites from the Limay river basin, Patagonia, Argentina, using energy dispersive X-ray fluorescence spectrometry: an aid to infer human group mobility

International Nuclear Information System (INIS)

Palacios, O.M.

2013-01-01

The investigation of hunter-gatherers archaeological sites in the Limay river basin, Patagonia, Argentina, raised questions concerning the lithic technology. The chemical characterization of artifacts, rocks and possible sources of provenances could help to elucidate the hunter-gatherer mobility. In three archaeological sites-Rincon Chico 2 (RCh2/87; 14 C 710 ± 60 BP), Cueva Traful I (CTI; 14 C 9430 ± 230 BP) and Casa de Piedra de Ortega (CPO; 14 C 2840 ± 80 BP), tools and debitage or discarded flakes made in black volcanic rock have been found. Nearby an extensive rock outcrop of black volcanite, Paso Limay quarry (CPL), with similar characteristics was located. Samples coming from these four sites were analyzed by energy dispersive X-ray fluorescence spectrometry. This characterization allowed the geochemical classification of the lithic material and to correlate the samples with the suspected source after a previous statistical analysis. The majority of the samples were classified as dacites and rhyolites. Only samples coming from CPO site, the closest place to CPL were made exclusively with the quarry rocks. A set of five samples from RCh2/87 and two samples from CTI appear to have same chemical composition as CPL in spite of this site is placed in the opposite bank of the Limay river suggesting that hunter-gatherers could accede to the quarry, eventually. Finally, only a set of five samples coming from RCh2/87 and CTI do not group with the quarry. This fact evidences the existence of secondary sources of supply. The information of this research allowed inferring ancient human mobility patterns in the region. (author)

Reptile and rodent parasites in raptor pellets in an archaeological context: the case of Epullán Chica (northwestern Patagonia, Argentina)

Science.gov (United States)

Beltrame, María Ornela; Fernández, Fernando Julián; Sardella, Norma Haydeé

2015-07-01

Paleoparasitology is the study of parasite remains from archaeological and paleontological sites. Raptor pellets can be used as source for paleoparasitological information in archaeological sites. However, this zooarchaeological material has been scarcely studied. Epullán Chica (ECh) is an archaeological site in northwestern Patagonia. This cave yielded remains from more than 2000 years before present. The aim of this paper was to study the parasite remains found in owl pellets from the archaeological site ECh, and to discuss the paleoparasitological findings in an archaeological context. Twenty two raptor pellets were examined for parasites. The pellets were whole processed by rehydration in a 0.5% water solution of trisodium phosphate, followed by homogenization, filtered and processed by spontaneous sedimentation. Eight out of 22 bird pellets examined were positive for parasites from reptiles and rodents. Representatives of 12 parasite taxa were recorded; nine of this parasitic species were reported for the first time from ancient samples from Patagonia. This is the first time that pellets give evidences of ancient reptile parasites from archaeological contexts. It is noteworthy that Late Holocene hunter-gatherers of the upper Limay River basin, could have been exposed to some of these zoonotic parasites. Future paleoparasitological studies on owl pellets may reflect even more the parasitological diversity of all micromammal and reptile species presents in ancient times.

Gamma irradiation as a phytosanitary treatment for fresh pome fruits produced in Patagonia

Science.gov (United States)

Pérez, J.; Lires, C.; Horak, C.; Pawlak, E.; Docters, A.; Kairiyama, E.

2009-07-01

Argentina produces 1.8 million tons/year of apples ( Malus domestica L.) and pears ( Pyrus communis L.) in the Patagonia region. Cydia pomonella, codling moth, and Grapholita molesta, Oriental fruit moth, ( Lepidoptera: Tortricidae) are quarantine pests in pome fruits. Irradiation is a promising phytosanitary treatment because a dose of 200 Gy completely prevents pest adult emergence. A pilot irradiation process of commercially packaged 'Red Delicious' apples and 'Packham's Triumph' pears was performed in an irradiation facility with a Cobalt 60 source. Quality analyses were carried out at 0, 2, 4, 6 and 8 months of storage (1 °C, RH 99%) to evaluate fruit tolerance at 200, 400 and 800 Gy. Irradiation at 200 and 400 Gy had no undesirable effects on fruit quality (pulp firmness, external colour, soluble solids content (SSC), titratable acidity (TA) and sensory evaluations). Irradiation of 'Red Delicious' apples and 'Packham's Triumph' pears can be applied as a commercial quarantine treatment with a minimum absorbed dose of 200 Gy (to control codling moth and Oriental fruit moth) and <800 Gy (according to quality results).

Reptiles of Chubut province, Argentina: richness, diversity, conservation status and geographic distribution maps

Science.gov (United States)

Minoli, Ignacio; Morando, Mariana; Avila, Luciano Javier

2015-01-01

Abstract An accurate estimation of species and population geographic ranges is essential for species-focused studies and conservation and management plans. Knowledge of the geographic distributions of reptiles from Patagonian Argentina is in general limited and dispersed over manuscripts from a wide variety of topics. We completed an extensive review of reptile species of central Patagonia (Argentina) based on information from a wide variety of sources. We compiled and checked geographic distribution records from published literature and museum records, including extensive new data from the LJAMM-CNP (CENPAT-CONICET) herpetological collection. Our results show that there are 52 taxa recorded for this region and the highest species richness was seen in the families Liolaemidae and Dipsadidae with 31 and 10 species, respectively. The Patagónica was the phytogeographic province most diverse in species and Phymaturus was the genus of conservation concern most strongly associated with it. We present a detailed species list with geographical information, richness species, diversity analyses with comparisons across phytogeographical provinces, conservation status, taxonomic comments and distribution maps for all of these taxa. PMID:25931966

VERY LONG BASELINE INTERFEROMETRY SEARCH FOR THE RADIO COUNTERPART OF HESS J1943+213

Energy Technology Data Exchange (ETDEWEB)

Gabanyi, K. E. [Konkoly Observatory, Research Centre for Astronomy and Earth Sciences of the Hungarian Academy of Sciences, P.O. Box 67, Budapest H-1525 (Hungary); Dubner, G.; Giacani, E. [Instituto de Astronomia y Fisica del Espacio (CONICET-UBA), CC 67, Suc. 28, 1428 Buenos Aires (Argentina); Paragi, Z.; Pidopryhora, Y. [Joint Institute for VLBI in Europe, Postbus 2, 7990 AA Dwingeloo (Netherlands); Frey, S., E-mail: gabanyi@konkoly.hu [FOeMI Satellite Geodetic Observatory, P.O. Box 585, H-1592 Budapest (Hungary)

2013-01-01

HESS J1943+213, a TeV point source close to the Galactic plane recently discovered by the H.E.S.S. Collaboration, was proposed to be an extreme BL Lacertae object, though a pulsar wind nebula (PWN) nature could not be completely discarded. To investigate its nature, we performed high-resolution radio observations with the European Very Long Baseline Interferometry Network (EVN) and reanalyzed archival continuum and H I data. The EVN observations revealed a compact radio counterpart of the TeV source. The low brightness temperature and the resolved nature of the radio source are indications against the beamed BL Lacertae hypothesis. The radio/X-ray source appears immersed in a {approx}1' elliptical feature, suggesting a possible galactic origin (PWN nature) for the HESS source. We found that HESS J1943+213 is located in the interior of a {approx}1 Degree-Sign diameter H I feature and explored the possibility of them being physically related.

Argentina chiama Italia: Friuli risponde

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Silvana Serafin

2010-03-01

Full Text Available The study analyzes the migratory waves from Friuli which, from the 1870s up to the post-World War II years, extensively moved towards Argentina, settling in the areas around the cities of Santa Fe, Cordoba, Entre Ríos, Chaco and Buenos Aires, but reaching also regions as far away as Patagonia. The accurate and well diffused net of the Fogolār Furlan, besides its function as friendly society, also provides to the promulgation of ancient traditions and mores among the new generations, transmitting on to them the cultural, linguistic and ethnic memory of the motherland. Epistles, tales, novels and poems form a paideia which is thus constantly being enlivened, eveng among those who assumed Argentinian nationality or were born in the country. Of utmost interest is, therefore, the resulting literary corpus, representing as it does a renewed search for identity in the form of a dialogue with the world, extending itself well beyond the contingency of boundaries and transmitting the universal essence of logos.

Childhood intestinal obstruction from lithobazoar | Hesse | African ...

African Journals Online (AJOL)

AAJ Hesse, W Appeadu-Mensah, J Welbeck, CEO Onuoha, J Boatey. Abstract. No Abstract. African Journal of Paediatric Surgery Vol. 1(2) 2005: 109-111. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT · AJOL African Journals Online. HOW TO USE AJOL.

Traditional Mapuche ecological knowledge in Patagonia, Argentina: fishes and other living beings inhabiting continental waters, as a reflection of processes of change.

Science.gov (United States)

Aigo, Juana; Ladio, Ana

2016-12-07

Understanding how people interpret environmental change and develop practices in response to such change is essential to comprehend human resource use. In the cosmology of the American indigenous peoples, as among the Mapuche people, freshwater systems are considered a living entity, where animals have an enormous role to play in the universe of meaning. However, human adaptive responses to freshwater system dynamics are scarcely examined. In this work a survey is carried out in three Mapuche communities of Argentine Patagonia to assess their traditional knowledge of the fishes and other non-human living beings that inhabit lakes and rivers. Both material and symbolic aspects are included, as are the differences in knowledge and use of the fishes between past and present times. Our methods were based on a quali-quantitative fieldwork approach. In-depth interviews were carried out with 36 individuals from three rural Mapuche populations in Neuquén province (Patagonia, Argentina). Free listing was used for inquiring about fish knowledge and use. Fishes were identified scientifically and ethnotaxonomically. In-depth analysis of the discourses was conducted, documenting the recognition, perception, and cultural significance of fluvial environments and their inhabitants. Quantitative survey results were analyzed with categorical statistical methods. The body of knowledge of the communities studied reflects the socio-environmental changes experienced by Patagonian freshwater bodies. According to local perception, non-human beings live in these water bodies, guarding the environment, and they should not be disturbed. At present, five different fish species are identified, three of which are exotic, having been introduced at the beginning of the 20th century by the white man. These exotic trout (Oncorhynchus mykiss and Salvelinus fontinalis) are considered ill omens, indicators of the white man's presence, and therefore their appearance presages negative events for the

Caracterización de las principales pesquerías del golfo San Jorge Patagonia, Argentina Characterization of the main fisheries in San Jorge Gulf, Patagonia, Argentina

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María Eva Góngora

2012-03-01

Full Text Available En el golfo San Jorge se desarrollan varias actividades económicas de relevancia, entre ellas dos pesquerías industriales: la pesquería de merluza común (Merluccius hubbsi Marini, 1933 y la pesquería de langostino patagónico (Pleoticus muelleri Bate, 1888, ambas se solapan espacial y temporalmente. En la pesquería de merluza del golfo San Jorge opera una flota fresquera de altura, compuesta por unas 20 embarcaciones, y una flota costera, compuesta por unas 30 embarcaciones. En esta pesquería se pesca alrededor del 10% de lo capturado en el stock sur de merluza. En la pesquería de langostino del golfo San Jorge opera una flota congeladora tangonera compuesta por 80 embarcaciones, responsable de más del 75% de los desembarques de langostino realizados en la República Argentina. Ambas pesquerías tienen como principal problema la captura incidental de merluza, en una de sus principales áreas de cría. En el presente trabajo se describe el manejo actual en las pesquerías del golfo San Jorge, el cual consiste principalmente en cierres espaciales y temporales para la pesca de langostino, y zonificaciones por estrato de flota para la merluza. En ninguna de las dos pesquerías descriptas se han tomado medidas que reduzcan eficazmente la captura incidental.In San Jorge Gulf, several important economic activities are developed, including two industrial fisheries: hake (Merluccius hubbsi Marini, 1933 and Argentine red shrimp (Pleoticus muelleri Bate, 1888. Both overlap spatially and temporally. The San Jorge Gulf hake fishery consists of a high-seas ice trawler fleet (n = 20 fishing vessels and a coastal fleet (n = 30 fishing vessels. These fisheries capture about 10% of the catch of the southern hake stock. The Argentine red shrimp fishery consists of a double-beam trawler fleet with 80 freezer vessels, responsible for more than 75% of shrimp landings in Argentina. The main problem of both fisheries is the bycatch of hake in one of its

Is forage productivity of meadows influenced by the afforestation of upstream hillsides? A study in NW Patagonia

Energy Technology Data Exchange (ETDEWEB)

Weigandt, M.; Gyenge, J.; Fernandez, M. E.; Varela, S.; Schlichter, T.

2011-07-01

Meadows are important reserves of water, with a key role in the maintenance of the biodiversity and productivity of ecosystems. In Patagonia, Argentina, afforestation with fast-growing exotic conifers has slowly but continuously increased over recent decades; though unfortunately, knowledge of the effects of afforestation on water resources remains scarce, with no information at all related to its impact on water dynamics and productivity of meadows located down slope to it. The effects of Pinus ponderosa afforestation on water dynamics (soil moisture contents and groundwater level) and productivity (aboveground forage productivity) of Northwest Patagonia meadows under xeric and humid conditions were analyzed. In the humid meadow, gravimetric soil water content, groundwater level and forage productivity were similar down slope of forested and non-forested slopes, with a trend towards higher forage productivity on the forested slope. In the xeric meadow, gravimetric soil water content was always higher down slope of the non-forested slope, with no difference in groundwater level between treatments. Forage productivity was statistically similar between situations (down slope of forested and non-forested slopes), with a trend towards higher productivity in the zone with higher soil water content. The main difference in the latter was related to differences in soil texture between zones. These results suggest that coniferous plantations located upstream of this type of meadow do not produce a direct effect on its aboveground forage productivity. These systems have high complexity linked to precipitation, geomorphology and previous history of land use, which determine primarily soil water dynamics and consequently, forage productivity. (Author) 42 refs.

El origen y evolución temprana de las serpientes : Análisis anatómico y filogenético de los ofidios cretácicos y paleógenos de la Patagonia y Bolivia

OpenAIRE

Scanferla, Carlos Agustín

2010-01-01

Este trabajo de tesis doctoral tiene como objetivo principal el análisis de dos relevantes escamados procedentes del Cretácico Superior de la Patagonia Argentina, Najash rionegrina y Dinilysia patagonica, como así también dos nuevas serpientes avanzadas del grupo de los Macrostomata, (denominados Taxón A y B) procedentes de la localidad del Terciario Inferior (Paleoceno) de Tiupampa, Bolivia. Se realizó un análisis anatómico detallado de estos taxones fósiles en conjunto con un gran número de...

Technology, Utopia and Scholarly Life: Ideals and Realities in the Work of Hermann Hesse

Science.gov (United States)

Roberts, Peter

2009-01-01

This article considers the relationship between technology, utopia and scholarly life in Hermann Hesse's novel, "The Glass Bead Game." In the first part of Hesse's book, the Glass Bead Game and the society of which it is a part, Castalia, are portrayed in idealistic terms. The second part of the novel chronicles the educational life of Joseph…

Exploring the extreme gamma-ray sky with HESS

International Nuclear Information System (INIS)

Sol, Helene

2006-01-01

The international HESS experiment. High Energy Stereoscopic System, fully operational since January 2004, is opening a new era for extreme gamma-ray astronomy. Located in Namibia, it is now the most sensitive detector for cosmic sources of very high energy (VHE) gamma-rays, in the tera-electron-volt (TeV) range. In July 2005, it had already more than double the number of sources detected at such energies, with the discovery of several active galactic nuclei (AGN), supernova remnants and plerions, a binary pulsar system, a microquasar candidate, and a sample of yet unidentified sources. HESS has also provide for the first time gamma-ray images of extended sources with the first astrophysical jet resolved in gamma-rays, and the first mapping of a shell supernova remnant, which proves the efficiency of in situ acceleration of particles up to 100 TeV and beyond

First South American Agathis (Araucariaceae), Eocene of Patagonia.

Science.gov (United States)

Wilf, Peter; Escapa, Ignacio H; Cúneo, N Rubén; Kooyman, Robert M; Johnson, Kirk R; Iglesias, Ari

2014-01-01

Agathis is an iconic genus of large, ecologically important, and economically valuable conifers that range over lowland to upper montane rainforests from New Zealand to Sumatra. Exploitation of its timber and copal has greatly reduced the genus's numbers. The early fossil record of Agathis comes entirely from Australia, often presumed to be its area of origin. Agathis has no previous record from South America. We describe abundant macrofossils of Agathis vegetative and reproductive organs, from early and middle Eocene rainforest paleofloras of Patagonia, Argentina. The leaves were formerly assigned to the New World cycad genus Zamia. Agathis zamunerae sp. nov. is the first South American occurrence and the most complete representation of Agathis in the fossil record. Its morphological features are fully consistent with the living genus. The most similar living species is A. lenticula, endemic to lower montane rainforests of northern Borneo. Agathis zamunerae sp. nov. demonstrates the presence of modern-aspect Agathis by 52.2 mya and vastly increases the early range and possible areas of origin of the genus. The revision from Zamia breaks another link between the Eocene and living floras of South America. Agathis was a dominant, keystone element of the Patagonian Eocene floras, alongside numerous other plant taxa that still associate with it in Australasia and Southeast Asia. Agathis extinction in South America was an integral part of the transformation of Patagonian biomes over millions of years, but the living species are disappearing from their ranges at a far greater rate.

CO2 and CH4 fluxes of contrasting pristine bogs in southern Patagonia (Tierra del Fuego, Argentina)

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Münchberger, Wiebke; Blodau, Christian; Kleinebecker, Till; Pancotto, Veronica

2015-04-01

South Patagonian peatlands cover a wide range of the southern terrestrial area and thus are an important component of the terrestrial global carbon cycle. These extremely southern ecosystems have been accumulating organic material since the last glaciation up to now and are - in contrast to northern hemisphere bogs - virtually unaffected by human activities. So far, little attention has been given to these pristine ecosystems and great carbon reservoirs which will potentially be affected by climate change. We aim to fill the knowledge gap in the quantity of carbon released from these bogs and in what controls their fluxes. We study the temporal and spatial variability of carbon fluxes in two contrasting bog ecosystems in southern Patagonia, Tierra del Fuego. Sphagnum-dominated bog ecosystems in Tierra del Fuego are similar to the ones on the northern hemisphere, while cushion plant-dominated bogs can almost exclusively be found in southern Patagonia. These unique cushion plant-dominated bogs are found close to the coast and their occurrence changes gradually to Sphagnum-dominated bogs with increasing distance from the coast. We conduct closed chamber measurements and record relevant environmental variables for CO2 and CH4 fluxes during two austral vegetation periods from December to April. Chamber measurements are performed on microforms representing the main vegetation units of the studied bogs. Gas concentrations are measured with a fast analyzer (Los Gatos Ultraportable Greenhouse Gas Analyzer) allowing to accurately record CH4 fluxes in the ppm range. We present preliminary results of the carbon flux variability from south Patagonian peat bogs and give insights into their environmental controls. Carbon fluxes of these two bog types appear to be highly different. In contrast to Sphagnum-dominated bogs, cushion plant-dominated bogs release almost no CH4 while their CO2 flux in both, photosynthesis and respiration, can be twice as high as for Sphagnum

Fouling community dominated by Metridium senile (Cnidaria: Anthozoa: Actiniaria in Bahía San Julián (southern Patagonia, Argentina

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Juan Pablo Martin

2015-06-01

Full Text Available The objective of this study is to provide information about a harbour-fouling community dominated by Metridium senile in southern Patagonia. Several steel tubes from the wharf of Puerto San Julián were extracted to perform repair tasks, allowing the attached benthic community to be studied. Sampling was conducted at three levels: lower intertidal, 3-4 m depth and 6-7 m depth. In the lower intertidal, M. senile had a relative abundance of 43%, the most abundant accompanying species being Perumytilus purpuratus, Mytilus edulis platensis and Aulacomya atra atra. At subtidal level, the anemone showed relative abundances of 64% and 65%, and was accompanied by Monocorophium insidiosum at 3-4 m depth and by polychaetes of families Sabellidae and Syllidae at 6-7 m at depth. In the lower intertidal, epibiosis was more frequent on P. purpuratus, A. atra atra and M. edulis platensis, while in the subtidal, the richness of substrate-organisms increased significantly and the anemone was fixed to A. atra atra, M. edulis platensis, Paramolgula gregaria, Crepipatella dilatata, Austromegabalanus psittacus, Hiatella arctica, Polyzoa opuntia, Pyura sp. and Sabellidae tubes. The ability of M. senile to settle on many different organisms, along with other strategies, makes it a colonizer able to displace other species that could compete with it for substratum. Given the cosmopolitan nature of M. senile, the fact that this species has not been previously reported in the coastal zone of the region, and the results of our study, we discuss the possibility that this sea anemone is an invasive alien species in southern Patagonia, or at least a cryptogenic species.

Estado actual del conocimiento de la familia Ceratopogonidae en la Patagonia (Diptera: Nematocera Current knowledge of the family Ceratopogonidae in Patagonia (Diptera: Nematocera

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Gustavo R. Spinelli

2009-06-01

Full Text Available Ceratopogonidae incluye pequeños dípteros nematoceros que crían en hábitats acuáticos o semiacuáticos. Hasta los '80, el conocimiento de su taxonomía en la Patagonia se hallaba limitado a la contribución de los comienzos de los '30 de Ingram y Macfie, sobre la base de material capturado en 1926-27, en el área del Parque Nacional Nahuel Huapi y zonas vecinas de Chile. En los últimos 25 años, se pusieron en marcha diferentes proyectos, resultando la descripción o registro de numerosos taxones para la región. Si se contabilizan los datos publicados, 102 especies habitan en la Patagonia, de las cuales 86 (84,31% son endémicas para la región. Este alto porcentaje es evidente en los bosques de Nothofagus, con 71 especies endémicas de este bioma, nueve lo son de la estepa y seis presentan registros en bosque y estepa. Datos aún no publicados concuerdan con este esquema. Diecinueve géneros están representados en la Patagonia, diez de ellos con amplia distribución, tres de distribución transantártica y seis son endémicos para el área. Para la misma, se hallan publicadas las revisiones de Forcipomyia, Atrichopogon, Borkenthelea, Macrurohelea y Paradasyhelea; se han finalizado y aún no publicado aquellas de Dasyhelea y Palpomyia, está muy avanzada la de Stilobezzia y se prevé comenzar con las de Austrohelea, Austrosphaeromias, Physohelea y Bezzia. Se calcula que estos datos no divulgados contienen al menos 55 especies todavía no descriptas. Con respecto a los aspectos biogeográficos se pueden destacar estudios que tienden a establecer relaciones entre las áreas reconocidas en esquemas biogeográficos propuestos para la región andina.Ceratopogonidae includes small nematoceran Diptera which breed in aquatic and semiaquatic habitats. Until the 80´s its taxonomic knowledge in Patagonia was limited to the early 30´s contribution of Ingram and Macfie, from material collected in 1926-27 in the area of the Nahuel Huapi National

Componentes de tecnologías para la pesca (instrumentos Traful en ambientes lacustres y boscosos andinos norpatagónicos, Argentina

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Alberto Enrique Pérez

2017-12-01

Full Text Available La funcionalidad de los Instrumentos Traful es incierta luego de 70 años de su descripción. A partir de su diseño morfológico, el contexto ambiental y arqueológico asociado, postulamos que son parte de un “instrumento compuesto” especializado en la pesca. Si bien presentan características singulares en el contexto lacustre y rivereño del interior de la Patagonia noroccidental argentina, se asemejan en cuestiones básicas a los pesos de líneas marinos de gran distribución magallánica.

First records of three species of Oxycraspedus Kuschel (Coleóptera: Belidae in Argentina and use of a predictive model to compare their potential distribution with the range of their host-plant, Araucaria araucana Primera cita de las tres especies de Oxycraspedus Kuschel (Coleóptera: Belidae en Argentina y uso de un modelo predictivo para comparar su distribución potencial con el rango de su planta huésped, la Araucaria araucana

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M.S. FERRER

2007-09-01

Full Text Available The first records of the three known species of Oxycraspedus Kuschel (Belidae: Oxycoryninae in Argentina are reported, and added to their known distribution in Chile. These weevils are of interest because of their association with the pehuén or monkey puzzle tree, Araucaria araucana, a species of conservation concern. Their distribution data are of value for the protection of biodiversity in natural areas of Patagonia. The potential distribution of Oxycraspedus, as predicted by a model using bioclimatic variables, is coincident as expected, with the geographic range of the araucaria host-plantSe reportan por primera vez en Argentina las tres especies de Oxycraspedus Kuschel (Belidae: Oxycoryninae y se añaden a su distribución en Chile. Estos gorgojos son de interés debido a su asociación con el pehuén Araucaria araucana, una especie de gran interés en temas de conservación. Los datos sobre su distribución son valiosos para proteger la biodiversidad en áreas de la Patagonia. La distribución potencial de Oxycraspedus predicha por un modelo a partir de variables bioclimáticas, es coincidente, como se esperaba, con el rango geográfico de su planta huésped, la araucaria

75 FR 32210 - United States v. Idaho Orthopaedic Society, Timothy Doerr, Jeffrey Hessing, Idaho Sports Medicine...

Science.gov (United States)

2010-06-07

..., Jeffrey Hessing, Idaho Sports Medicine Institute, John Kloss, David Lamey, and Troy Watkins; Proposed... Sports Medicine Institute, John Kloss, David Lamey, and Troy Watkins, Civil Case No. 10-268. On May 28..., Jeffrey Hessing, Idaho Sports Medicine Institute, John Kloss, David Lamey, and Troy Watkins, Defendants...

Hess Tower field study: sonic measurements at a former building-integrated wind farm site

Science.gov (United States)

Araya, Daniel

2017-11-01

Built in 2010, Hess Tower is a 29-story office building located in the heart of downtown Houston, TX. Unique to the building is a roof structure that was specifically engineered to house ten vertical-axis wind turbines (VAWTs) to partially offset the energy demands of the building. Despite extensive atmospheric boundary layer (ABL) wind tunnel tests to predict the flow conditions on the roof before the building was constructed, the Hess VAWTs were eventually removed after allegedly one of the turbines failed and fell to the ground. This talk presents in-situ sonic anemometry measurements taken on the roof of Hess Tower at the former turbine locations. We compare this wind field characterization to the ABL wind tunnel data to draw conclusions about building-integrated wind farm performance and prediction capability.

The camera of the fifth H.E.S.S. telescope. Part I: System description

Energy Technology Data Exchange (ETDEWEB)

Bolmont, J., E-mail: bolmont@in2p3.fr [LPNHE, Université Pierre et Marie Curie Paris 6, Université Denis Diderot Paris 7, CNRS/IN2P3, 4 Place Jussieu, F-75252 Paris Cedex 5 (France); Corona, P.; Gauron, P.; Ghislain, P.; Goffin, C.; Guevara Riveros, L.; Huppert, J.-F.; Martineau-Huynh, O.; Nayman, P.; Parraud, J.-M.; Tavernet, J.-P.; Toussenel, F.; Vincent, D.; Vincent, P. [LPNHE, Université Pierre et Marie Curie Paris 6, Université Denis Diderot Paris 7, CNRS/IN2P3, 4 Place Jussieu, F-75252 Paris Cedex 5 (France); Bertoli, W.; Espigat, P.; Punch, M. [APC, AstroParticule et Cosmologie, Université Paris Diderot, CNRS/IN2P3, CEA/Irfu, Observatoire de Paris, Sorbonne Paris Cité, 10, rue Alice Domon et Léonie Duquet, F-75205 Paris Cedex 13 (France); Besin, D.; Delagnes, E.; Glicenstein, J.-F. [CEA Saclay, DSM/IRFU, F-91191 Gif-Sur-Yvette Cedex (France); and others

2014-10-11

In July 2012, as the four ground-based gamma-ray telescopes of the H.E.S.S. (High Energy Stereoscopic System) array reached their tenth year of operation in Khomas Highlands, Namibia, a fifth telescope took its first data as part of the system. This new Cherenkov detector, comprising a 614.5 m{sup 2} reflector with a highly pixelized camera in its focal plane, improves the sensitivity of the current array by a factor two and extends its energy domain down to a few tens of GeV. The present part I of the paper gives a detailed description of the fifth H.E.S.S. telescope's camera, presenting the details of both the hardware and the software, emphasizing the main improvements as compared to previous H.E.S.S. camera technology.

Difilobotriosis humana: Un caso en área no endémica de la Argentina

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Diego E. Cargnelutti

2012-02-01

Full Text Available La difilobotriosis es una parasitosis intestinal causada por la infección de cestodos del genero Diphyllobothrium. En la Argentina, la Patagonia Andina es considerada una zona endémica para esta parasitosis. La infección por Diphyllobothrium latum no ha sido previamente notificada en la provincia de Mendoza; en este trabajo comunicamos un caso de esta parasitosis que fue confirmada por el análisis de las características morfológicas de los huevos eliminados con la materia fecal de un paciente infectado. Se destaca la necesidad de información y capacitación de los profesionales de la salud en el diagnóstico y tratamiento de parasitosis no endémicas.

Freshwater fishes of Patagonia: conservation and fisheries.

Science.gov (United States)

Cussac, V E; Habit, E; Ciancio, J; Battini, M A; Riva Rossi, C; Barriga, J P; Baigún, C; Crichigno, S

2016-07-01

The absence of much literature on the Patagonian fish fauna in comparison with that of the neotropics, has previously been blamed on its poor species diversity. Knowledge of the fishes of Patagonia, however, rose sharply at the beginning of the present century, allowing for an understanding of the complex biogeographical history that has led to the present diversity and distribution patterns. There are several new and potential threats to biodiversity and conservation of Patagonian fishes, such as the introduction of exotic species, damming, climate change and changes geared to safeguard economic interests, often acting synergistically. A great amount of new information is now available and the aim of the present review is to articulate this knowledge in a comprehensive way in order to aid in the development of tools to face the increasing challenges posed by environmental change and human activity. Knowledge about fishes of Patagonia has grown at the same time as human actions, and presence. © 2016 The Fisheries Society of the British Isles.

LA GEOPEDOLOGIA COMO BASE PARA ZONIFICAR LA APTITUD FORESTAL EN UNA CUENCA DEL NOROESTE DE LA PATAGONIA ARGENTINA

Directory of Open Access Journals (Sweden)

Maria Cristina Frugoni

2016-12-01

Full Text Available Geopedology at a semi-detailed scale (1:50.000 was carried out in Buta Mallín catchment which includes an area of 21.065ha, in the northwest of Neuquén province, Argentine Patagonia. Geopedology provides a spatial dimension of soil-landscape relations, which are displayed in a map and its legend, showing the geoforms (contours and their soils (content, based on the premise that soil is landscape as well as profile. According to this approach three landscapes were recognized: glacial modeled mountains, plateau and valley. The relief consists mainly of steep to very steep slopes, and valley bottoms with poorly drained soils. Lithology (parent material corresponds to holocene volcanic ash in the western sector of the study area, while the eastern sector is dominated by tuff. Twenty terrain forms and their soils were identified. With this basic information, attribute tables were constructed considering landscape and soil properties. Regarding soils, physical fertility properties were considered, since these are the most correlated ones with Pinus ponderosa (pino ponderosa growth, the main species used in afforestation in Patagonia. Those tables were included and analized with a GIS (Geographic Information System to obtain a forest suitability map. The study area shows four forest suitability classes. Suitable: 37ha; moderately suitable: 4.512ha; marginally suitable: 6.072ha; not suitable: 10.444ha. The main limitations of the area are the very steep slopes, height and the areas dominated by rock outcrops and detrital covers. Nothofagus antarctica (ñire shrubs cover part of the suitable areas; because of conservation criteria of these natural communities, these lands were considered not suitable. On the other side, there are more than 4.000 ha of moderately suitable lands, which can be considered for a more detailed study. Transhumant cattle raising is the main land use system in this catchment, which is an ancient culture of the Northern Neuquian

A Middle Jurassic heterodontosaurid dinosaur from Patagonia and the evolution of heterodontosaurids

Science.gov (United States)

Pol, Diego; Rauhut, Oliver W. M.; Becerra, Marcos

2011-05-01

Heterodontosauridae is a morphologically divergent group of dinosaurs that has recently been interpreted as one of the most basal clades of Ornithischia. Heterodontosaurid remains were previously known from the Early Jurassic of southern Africa, but recent discoveries and studies have significantly increased the geographical and temporal range for this clade. Here, we report a new ornithischian dinosaur from the Middle Jurassic Cañadón Asfalto Formation in central Patagonia, Argentina. This new taxon, Manidens condorensis gen. et sp. nov., includes well-preserved craniomandibular and postcranial remains and represents the only diagnostic ornithischian specimen yet discovered in the Jurassic of South America so far. Derived features of its anatomy indicate that Manidens belongs to Heterodontosauridae, as the sister taxon of Heterodontosaurus and other South African heterodontosaurids. The presence of posterior dentary teeth with high crowns but lacking extensive wear facets in Manidens suggests that this form represents an intermediate stage in the development of the remarkable adaptations to herbivory described for Heterodontosaurus. The dentition of Manidens condorensis also has autapomorphies, such as asymmetrically arranged denticles in posterior teeth and a mesially projected denticle in the posteriormost teeth. At an estimated total length of 60-75 cm, Manidens furthermore confirms the small size of basal heterodontosaurids.

Biometric identification of capillariid eggs from archaeological sites in Patagonia.

Science.gov (United States)

Taglioretti, V; Fugassa, M H; Beltrame, M O; Sardella, N H

2014-06-01

Numerous eggs of capillariid nematodes have been found in coprolites from a wide range of hosts and in raptor pellets in archaeological samples from Patagonia. The structure and sculpture of the eggshell of these nematodes and their biometry are commonly used for identification. The aim of this study was to determine whether eggs of the genus Calodium with similar morphology, found in different archaeological samples from Patagonia, belong to the same species. For this purpose, capillariid eggs (N= 843) with thick walls and radial striations were studied by permutational multivariate analysis of variance (PERMANOVA). Eggs exhibiting similar shape and structure also showed similar biometry, regardless of the zoological origin of coprolites (P= 0.84), host diet (P= 0.19), character of the archaeological sites (P= 0.67) and chronology (P= 0.66). Thus, they were attributed to the same species. We suggest that an unidentified zoonotic species of the genus Calodium occurred in the digestive tract of a wide range of hosts in Patagonia during the Holocene and that both human and animal populations were exposed to this parasite during the Holocene in the study area.

Plankton dynamics and photosynthesis responses in a eutrophic lake in Patagonia (Argentina: influence of grazer abundance and UVR Dinámica del plancton y respuestas fotosintéticas en una laguna eutrófica de Patagonia (Argentina: influencia de la abundancia de herbívoros y RUV

Directory of Open Access Journals (Sweden)

Rodrigo J Gonçalves

2011-01-01

Full Text Available A natural plankton population from the eutrophic lake Cacique Chiquichano, in the Argentine Patagonia, was monitored for one year to evaluate changes in photosynthetic parameters as a result of exposure to ultraviolet radiation (UVR, 280-400 nm, grazer abundance, and the taxonomic composition of the phytoplankton community. Both physical (temperature, solar radiation and biological (grazers, taxonomic composition, photosynthetic parameters variables fluctuated throughout the study. Crustacean zooplankton showed alternating dominance between cladocerans (Daphnia spinulata and copepods (Metacyclops mendocinus. The phytoplankton community underwent concomitant changes throughout the year, with cyanobacteria and diatoms alternately dominating. In addition, although copepod abundance was not significantly related to changes in phytoplankton, the presence of D. spinulata was significant during periods of more transparent water; these periods were dominated by diatoms. On the other hand, cyanobacteria dominated the phytoplankton assemblage when the penetration of solar radiation into the water column was lower. Photosynthetic inhibition due to UVR decreased during the diatom-dominated periods. In contrast, inhibition increased along with the proportion of cyanobacteria, likely as a result of acclimation to low irradiance during the lake's phase of lower transparency. Moreover, the presence of D. spinulata was associated with the increased penetration of solar radiation into the water column, resulting in an indirect increment in the inhibition of cyanobacteria photosynthesis. The results suggest that both solar radiation and grazing abundance strongly influence the dynamics and photosynthetic activity of the phytoplankton in Lake Cacique Chiquichano.Se estudió a lo largo del año una comunidad planctónica natural de la laguna eutrófica Cacique Chiquichano de Patagonia-Argentina, para evaluar los cambios en parámetros fotosintéticos como resultados

Pobreza y migraciones en una ciudad intermedia argentina. Una mirada desde la historia (Neuquén, 1980

Directory of Open Access Journals (Sweden)

Joaquín Perren

2015-01-01

Full Text Available El presente artículo tiene como objetivo estudiar los vínculos entre la pobreza y las migra - ciones en Neuquén (Patagonia, Argentina a principios de la década de 1980. En tér - minos metodológicos, este estudio emplea la información que brinda el Censo Nacional de Población y Vivienda de 1980 por radio censal. Al mismo tiempo, y con el propósito de detallar muchos de los fenómenos que se analizan, se presentan cartografías temáticas que fueron elaboradas utilizando sistemas de información geográfica, y en particular el programa ArcView GIS 3.3.

Chemosensory perception and medicinal plants for digestive ailments in a Mapuche community in NW Patagonia, Argentina.

Science.gov (United States)

Molares, Soledad; Ladio, Ana

2009-06-25

To document the richness of plant species used in gastrointestinal disorders and to investigate about the criteria of aroma and flavor associated with its recognition, classification, selection and use. Ethnobotanical fieldwork consisted of interviews to 30 inhabitants living in a Mapuche community of Northwestern Patagonia; data collected was analyzed by means of non-parametric statistics. This work records 75 ethnospecies, pertaining to 40 botanic families. Lamiaceae, Asteraceae and Chenopodiaceae were the most frequently mentioned and described in terms of smell and taste. Most of species (69%) have notable aroma and/or flavor characteristics. The species presenting highest consensus in the population are positively associated with a higher frequency of organoleptic descriptions. In addition, local people consider these perceptions to be potentially useful in the search for substitutes when species are scarce or disappear from a locality. It is possible to establish a preliminary system of classification of medicinal plants based on their organoleptic characteristics and relate this to their effects on health. Moreover the cultural interpretation of smell and taste is of great heuristic importance to ethnopharmacology, in that it indicates which plants are most likely to contain the main active ingredients sought.

Preandean geological configuration of the eastern North Patagonian Massif, Argentina

Directory of Open Access Journals (Sweden)

Daniel A. Gregori

2013-11-01

Full Text Available The Preandean geological configuration of the eastern North Patagonian Massif is established through the use of geological and geophysical analysis. The positive gravity anomalies located near the Atlantic coast are due to 535 and 540 Ma old rocks belonging to the Pampean Orogeny (Precambrian–middle Cambrian, which are widely recognized in central and northern Argentina. The Famatinian Cycle (Ordovician–Devonian is represented by a Silurian–Devonian marine basin equivalent to those of eastern-central Argentina and South Africa, and which was deformed at the end of the Devonian by an ∼E–W to WNW–ESE compressional event, part of the Famatinian Orogeny. Containing strong gravity gradients, the NW–SE belt is coincident with fault zones which were originated during the Gondwanide Orogeny. This event also produced NW–SE overthrusting of the Silurian–Devonian sequences and strike-slip faults that displaced blocks in the same direction. This deformation event belongs to the Gondwanide Orogeny that includes movements related to a counterclockwise rotation of blocks in northern Patagonia. The strong negative anomalies located in the western part of the area stem from the presence of rocks of the Jurassic Cañadón Asfalto basin interbedded in the Marifil Complex. These volcaniclastic sequences show mild deformation of accommodation zones in a pre-Jurassic paleorelief.

Uncinaria hamiltoni (Nematoda: Ancylostomatidae) in South American Sea Lions, Otaria flavescens, From Northern Patagonia, Argentina

OpenAIRE

Berón-Vera, B.; Crespo, Enrique Alberto; Raga Esteve, Juan Antonio; Pedraza, S. N.

2004-01-01

Thirty-one South American sea lion pups (Otaria flavescens) found dead in Punta León, Argentina, during the summer of 2002, were examined for hookworms (Uncinaria hamiltoni). Parasite parameters were analyzed in 2 locations of the rookery, i.e., a traditional, well-structured breeding area and an expanding area with juveniles and a lax social structure. Prevalence of hookworms was 50% in both localities, and no difference was observed in prevalence between pup sexes (P > 0.05). Hookworms were...

A Tenebrionid beetle's dataset (Coleoptera, Tenebrionidae) from Peninsula Valdés (Chubut, Argentina).

Science.gov (United States)

Cheli, Germán H; Flores, Gustavo E; Román, Nicolás Martínez; Podestá, Darío; Mazzanti, Renato; Miyashiro, Lidia

2013-12-18

The Natural Protected Area Peninsula Valdés, located in Northeastern Patagonia, is one of the largest conservation units of arid lands in Argentina. Although this area has been in the UNESCO World Heritage List since 1999, it has been continually exposed to sheep grazing and cattle farming for more than a century which have had a negative impact on the local environment. Our aim is to describe the first dataset of tenebrionid beetle species living in Peninsula Valdés and their relationship to sheep grazing. The dataset contains 118 records on 11 species and 198 adult individuals collected. Beetles were collected using pitfall traps in the two major environmental units of Peninsula Valdés, taking into account grazing intensities over a three year time frame from 2005-2007. The Data quality was enhanced following the best practices suggested in the literature during the digitalization and geo-referencing processes. Moreover, identification of specimens and current accurate spelling of scientific names were reviewed. Finally, post-validation processes using DarwinTest software were applied. Specimens have been deposited at Entomological Collection of the Centro Nacional Patagónico (CENPAT-CONICET). The dataset is part of the database of this collection and has been published on the internet through GBIF Integrated Publishing Toolkit (IPT) (http://data.gbif.org/datasets/resource/14669/). Furthermore, it is the first dataset for tenebrionid beetles of arid Patagonia available in GBIF database, and it is the first one based on a previously designed and standardized sampling to assess the interaction between these beetles and grazing in the area. The main purposes of this dataset are to ensure accessibility to data associated with Tenebrionidae specimens from Peninsula Valdés (Chubut, Argentina), also to contribute to GBIF with primary data about Patagonian tenebrionids and finally, to promote the Entomological Collection of Centro Nacional Patagónico (CENPAT

Una tortuga Chelidae (Testudines: Pleurodira de cuello largo en el Grupo Neuquén, Río Negro, Argentina: Significado cronológico y paleobiogeográfico A long-necked Chelidae turtle (Testudines: Pleurodira from the Neuquén Group, Río Negro, Argentina: Chronological and paleobiogeographical significance

Directory of Open Access Journals (Sweden)

Marcelo S de la Fuente

2010-07-01

Full Text Available Diferentes restos de una tortuga Chelidae cuellilarga de la Formación Anacleto (Santoniano tardío-Campaniano temprano, aflorante en la localidad de Valle de la Luna Rojo, Provincia de Río Negro, Argentina, son conferidos a la especie Yaminuechelys cf. gasparinii De la Fuente, De Lapparent de Broin y Manera de Bianco, 2001. Ellos representan el registro más antiguo para el género y los Chelidae de cuello largo. Se sugiere que el ancestro común de Yaminuechelys e Hydromedusa habitó en Gondwana meridional con anterioridad a la separación de Australia. La presencia de este taxón en el Cretácico Tardío en Patagonia y algunos de los resultados de los análisis filogenéticos previos apoyan la hipótesis sobre una temprana diferenciación y diversificación de los quélidos en dicha región de Gondwana.A long necked chelid turtle species from the Anacleto Formation (late Santonian-early Campanian cropping out at Valle de La Luna Rojo, Río Negro Province, Argentina, is assigned to Yaminuechelys cf. gasparinii De la Fuente, De Lapparent de Broin and Manera de Bianco, 2001 and it represents the oldest record of a long-necked chelid. We suggest that the common ancestor of Yaminuechelys and Hydromedusa lived in Southern Gondwana before the separation of Australia from the remaining Southern Gondwanan landmasses. The presence of this chelid taxon in the Late Cretaceous of Patagonia and some previous phylogenetic analyses support the hypothesis of an early differentiation and diversification of chelids on Southern Gondwana.

Telón de fondo: Paisajes de desierto y alteridad en la fotografía de la Patagonia (1880-1900 Backdrop: Desert and Alterity Landscapes in the Photography of Patagonia (1880-1900

Directory of Open Access Journals (Sweden)

Carlos Masotta

2009-12-01

Full Text Available El paisaje patagónico construido por la fotografía del período 1880-1900 fue un marco en donde se llevó a cabo el ingreso civilizatorio. Luego de una caracterización general del problema (el paisaje desierto como «escenificación de ausencia» en torno a los primeros álbumes de Estado sobre la región, centro el análisis de este artículo en dos obras que describieron el Territorio de Chubut: Viaje a la Patagonia Austral (1886 del Coronel Luis Fontana y la Excursión a la Patagonia y a los Andes de Aarón Anchorena (1902. Entre ellas puede observarse la articulación de una mirada militar y civil donde el paisaje fotográfico del desierto se involucra en la toma material y simbólica del territorio como un escenario donde se «naturaliza» la actuación de un ingreso civilizatorio y la desaparición de los pueblos indígenas.The Patagonian landscape built up by photography during the 1880-1900 periods was the framework in which the civilizing entrance took action. After a general description of the problem (the deserted landscape as the staging of absence about the first State's albums on the region, I focus the analysis on two works describing the Territory of Chubut: Viaje a la Patagonia Austral (Trip to Southern Patagonia by Coronel Luis Fontana (1886 and Excursion a la Patagonia y a los Andes (Tour to Patagonia and the Andes, de Aaron Anchorena (1902. The articulation of a military and civil glance can be observed between them, where the photographic landscape of the desert is involved in the material and symbolic shot of the territory as a stage where the acting of a civilizing entrance and the disappearance of the indigenous peoples is naturalized.

Unravelling the collapse mechanisms at a Jurassic caldera of the Chon Aike silicic LIP in Southern Patagonia (47 deg. 15 'S, 71 deg. 40'W), Argentina

International Nuclear Information System (INIS)

Sruoga, P; Japas, S; Salani, F; Kleiman, L; Graffigna, M

2008-01-01

La Peligrosa Caldera is located at Sierra Colorada (47 0 15'S, 71 0 40' W) in the Chon-Aike silicic LIP. It represents an unique window to understand the eruptive mechanisms that prevailed throughout the ignimbritic flare-up in Southern Patagonia during middle to late Jurassic times. Key pieces of lithologic and structural evidences are taken into account to reconstruct the volcanic structure.

Unravelling the collapse mechanisms at a Jurassic caldera of the Chon Aike silicic LIP in Southern Patagonia (47° 15 'S, 71° 40'W), Argentina

Science.gov (United States)

Sruoga, P.; Japas, S.; Salani, F.; Kleiman, L.; Graffigna, M.

2008-10-01

La Peligrosa Caldera is located at Sierra Colorada (47° 15'S, 71° 40' W) in the Chon-Aike silicic LIP. It represents an unique window to understand the eruptive mechanisms that prevailed throughout the ignimbritic flare-up in Southern Patagonia during middle to late Jurassic times. Key pieces of lithologic and structural evidences are taken into account to reconstruct the volcanic structure.

Geology and Conceptual Model of the Domuyo Geothermal Area, Patagonia, Argentina

Science.gov (United States)

Fragoso, A. S.; Ferrari, L.; Norini, G.

2017-12-01

Cerro Domuyo is the highest mountain in Patagonia and its western slope is characterized by thermal springs with boiling fluids as well as silicic domes and pyroclastic deposits that suggest the existence of a geothermal reservoir. Early studies proposed that the thermal springs were fault-controlled and the reservoir was located in a graben bounded by E-W normal faults. A recent geochemical study estimated a temperature of 220ºC for the fluid reservoir and a thermal energy release of 1.1 GW, one of the world largest advective heat flux from a continental volcanic center. We carried out a geologic survey and U-Pb and U-Th geochronologic study to elaborate an updated conceptual model for the Domuyo geothermal area. Our study indicates that the Domuyo Volcanic Complex (DVC) is a dome complex overlying an older, Middle Miocene to Pliocene volcanic sequence widely exposed to the southwest and to the north, which in turn covers: 1) the Jurassice-Early Creteacoeus Neuquen marine sedimentary succession, 2) silicic ignimbrites dated at 186.7 Ma and, 3) the Paleozoic metamorphic basement intruded by 288 Ma granite bodies. These pre-Cenozoic successions are involved in dominantly N-S trending folds and thrust faults later displaced by E-W striking normal faults with a right lateral component of motion that underlie the DVC. The volcanic cycle forming the DVC is distinctly bimodal with the emplacement of massive silicic domes but also less voluminous olivine basalts on its southern slope. The central dome underwent a major collapse that produced 0.35 km3 of ash and block flow and associated pyroclastic flows that filled the valley to the southwest up to 30 km from the source. This was followed by a voluminous effusive activity that formed silicic domes dated between 254-322 Ky, which is inferred to overlain a partially molten silicic magma chamber. Integrating the geologic model with magnetotelluric and gravity surveys we developed a conceptual model of the geothermal system

The missing GeV γ-ray binary: searching for HESS J0632+057 with Fermi-LAT

NARCIS (Netherlands)

Caliandro, G.A.; Hill, A.B.; Torres, D.F.; Hadasch, D.; Ray, P.; Abdo, A.; Hessels, J.W.T.; Ridolfi, A.; Possenti, A.; Burgay, M.; Rea, N.; Tam, P.H.T.; Dubois, R.; Dubus, G.; Glanzman, T.; Jogler, T.

2013-01-01

The very high energy (VHE; >100 GeV) source HESS J0632+057 has been recently confirmed as a γ-ray binary, a subclass of the high-mass X-ray binary population, through the detection of an orbital period of 321 d. We performed a deep search for the emission of HESS J0632+057 in the GeV energy range

Green marketing impact on a company’s success : studying the case of Patagonia

OpenAIRE

Ventura, Manuel Robles Machado Simões

2016-01-01

The increased demand for products with low environmental impact has increased the number of green marketing campaigns released during the last years. However, the impact of green marketing in companies’ performance is not clear. It mainly depends on the company’s characteristics and the perceived honesty of their green claims. Thus, the present study aimed to analyze the impact of green marketing in a particular company, Patagonia. Patagonia is recognized as a pioneer in corporate environment...

Saccharomyces uvarum is responsible for the traditional fermentation of apple chicha in Patagonia.

Science.gov (United States)

Rodríguez, Maria E; Pérez-Través, Laura; Sangorrín, Marcela P; Barrio, Eladio; Querol, Amparo; Lopes, Christian A

2017-01-01

Apple chicha is a fresh low alcoholic beverage elaborated by aboriginal communities of Andean Patagonia (Argentina and Chile). In the present work, we identified the yeast microbiota associated with this fermentation, and characterized genetically those belonging to the genus Saccharomyces. Both Saccharomyces cerevisiae and S. uvarum were found in the analyzed fermentations. Phylogenetic and population structure analyses based on genes sequence analysis were carried out for both S. cerevisiae and S. uvarum strains obtained in this study and a set of additional strains from diverse origins. The results demonstrate that S. cerevisiae strains from apple chicha belong to the big group of wine/European strains of this species, while S. uvarum strains were included in the Holartic population of this species. Additionally, some S. uvarum strains from chichas evidenced as an admixture of both pure Holartic and pure South American populations. Our results suggest that Holartic strains could have been introduced in South America together with the domestication of apple trees by Mapuche communities. This Holartic population suffered admixis with the naturally present South American population of this species, originating strains bearing genetic features from the two populations, detectable in both chichas and natural habitats. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

A Tenebrionid beetle’s dataset (Coleoptera, Tenebrionidae from Peninsula Valdés (Chubut, Argentina

Directory of Open Access Journals (Sweden)

German Cheli

2013-12-01

Full Text Available The Natural Protected Area Peninsula Valdés, located in Northeastern Patagonia, is one of the largest conservation units of arid lands in Argentina. Although this area has been in the UNESCO World Heritage List since 1999, it has been continually exposed to sheep grazing and cattle farming for more than a century which have had a negative impact on the local environment. Our aim is to describe the first dataset of tenebrionid beetle species living in Peninsula Valdés and their relationship to sheep grazing. The dataset contains 118 records on 11 species and 198 adult individuals collected. Beetles were collected using pitfall traps in the two major environmental units of Peninsula Valdés, taking into account grazing intensities over a three year time frame from 2005–2007. The Data quality was enhanced following the best practices suggested in the literature during the digitalization and geo-referencing processes. Moreover, identification of specimens and current accurate spelling of scientific names were reviewed. Finally, post-validation processes using DarwinTest software were applied. Specimens have been deposited at Entomological Collection of the Centro Nacional Patagónico (CENPAT-CONICET. The dataset is part of the database of this collection and has been published on the internet through GBIF Integrated Publishing Toolkit (IPT (http://data.gbif.org/datasets/resource/14669/. Furthermore, it is the first dataset for tenebrionid beetles of arid Patagonia available in GBIF database, and it is the first one based on a previously designed and standardized sampling to assess the interaction between these beetles and grazing in the area. The main purposes of this dataset are to ensure accessibility to data associated with Tenebrionidae specimens from Peninsula Valdés (Chubut, Argentina, also to contribute to GBIF with primary data about Patagonian tenebrionids and finally, to promote the Entomological Collection of Centro Nacional Patag

A Tenebrionid beetle’s dataset (Coleoptera, Tenebrionidae) from Peninsula Valdés (Chubut, Argentina)

Science.gov (United States)

Cheli, Germán H.; Flores, Gustavo E.; Román, Nicolás Martínez; Podestá, Darío; Mazzanti, Renato; Miyashiro, Lidia

2013-01-01

Abstract The Natural Protected Area Peninsula Valdés, located in Northeastern Patagonia, is one of the largest conservation units of arid lands in Argentina. Although this area has been in the UNESCO World Heritage List since 1999, it has been continually exposed to sheep grazing and cattle farming for more than a century which have had a negative impact on the local environment. Our aim is to describe the first dataset of tenebrionid beetle species living in Peninsula Valdés and their relationship to sheep grazing. The dataset contains 118 records on 11 species and 198 adult individuals collected. Beetles were collected using pitfall traps in the two major environmental units of Peninsula Valdés, taking into account grazing intensities over a three year time frame from 2005–2007. The Data quality was enhanced following the best practices suggested in the literature during the digitalization and geo-referencing processes. Moreover, identification of specimens and current accurate spelling of scientific names were reviewed. Finally, post-validation processes using DarwinTest software were applied. Specimens have been deposited at Entomological Collection of the Centro Nacional Patagónico (CENPAT-CONICET). The dataset is part of the database of this collection and has been published on the internet through GBIF Integrated Publishing Toolkit (IPT) (http://data.gbif.org/datasets/resource/14669/). Furthermore, it is the first dataset for tenebrionid beetles of arid Patagonia available in GBIF database, and it is the first one based on a previously designed and standardized sampling to assess the interaction between these beetles and grazing in the area. The main purposes of this dataset are to ensure accessibility to data associated with Tenebrionidae specimens from Peninsula Valdés (Chubut, Argentina), also to contribute to GBIF with primary data about Patagonian tenebrionids and finally, to promote the Entomological Collection of Centro Nacional Patag

Study of the sensitivity of the H.E.S.S.2 experiment below 300 GeV and indirect search of dark matter with the H.E.S.S. Data

International Nuclear Information System (INIS)

Masbou, J.

2010-09-01

The H.E.S.S. telescope (High Energy Stereoscopic System) is an experiment of four imaging Cherenkov Telescope looking on gamma rays from 100 GeV to 100 TeV. In 2012, the experiment will be upgraded in a second phase with a fifth telescope of 28 m of diameter in the center of the existing system. At the threshold of 15 GeV, electromagnetic shower will be detected only by this big telescope so a new data analysis is needed. A new method based on a multidimensional analysis has been developed. Therefore, the energy of electromagnetic shower is well reconstructed with a good discrimination down to 30 GeV. At low energy, the sensitivity will be at a few percent of the Crab in 50 hours. This new method has been tested on H.E.S.S. data and is very competitive with respect to the other energy reconstruction methods; an extension for stereoscopic events is also shown. The calibration processes and the results of tests of photomultipliers are described. A propagation model of cosmic rays has been developed to study diffuse gamma ray emission. Protons and helium nuclei have been propagated in the galaxy to estimate the emission of neutral pion decays after an interaction with the interstellar medium. The map production is described from the beginning to the end. I have estimated the sensitivity of H.E.S.S. to the prediction of the model. The Sagittarius dwarf galaxy is studied as a dark matter dominated object. I used the most efficient analysis of the H.E.S.S collaboration and decomposed the data as a function of the zenith angle to decrease the energy threshold. (author)

Airborne laser altimetry survey of Glaciar Tyndall, Patagonia

DEFF Research Database (Denmark)

Keller, K.; Casassa, G.; Rivera, A.

2007-01-01

The first airborne laser altimetry measurements of a glacier in South America are presented. Data were collected in November of 2001 over Glaciar Tyndall, Torres del Paine National Park, Chilean Patagonia, onboard a Twin Otter airplane of the Chilean Air Force. A laser scanner with a rotating...

Micro-environmental changes induced by shape and size of forest openings: effects on Austrocedrus chilensis and Nothofagus dombeyi seedlings performance in a Pinus contorta plantation of Patagonia, Argentina

Energy Technology Data Exchange (ETDEWEB)

Pafundi, L.; Urretavizcaya, M.F.; Defosse, G.E.

2016-07-01

Aim of the study: to analyze, within a Pinus contorta plantation, the effects of artificially created small rectangular and small medium circular canopy gaps on: i) photosynthetic active radiation (PAR), and soil temperature and moisture, and ii) survival and growth of planted Austrocedrus chilensis and Nothofagus dombeyi seedlings, species which formerly composed the natural forest of the area. Study area: A 2 ha stand of a Pinus contorta stand in Los Alerces National Park, Argentina (42°43’S, 71°43’W, 490 m.a.s.l.). Material and methods: The Pinus contorta stand was 25 yr old, 22 m height and 26 cm DBH, presenting 1000 trees ha-1 of density and 53 m2 ha-1 of basal area. In 2009, rectangular and circular gaps were created within the stand and then seedlings were planted. During two growing seasons (2010-2011 and 2011-2012), PAR, soil temperature and moisture were measured in gaps and understory (control), and seedling survival and growth in gaps. Main results: During both seasons, soil temperature did not differ among gaps and control, whereas PAR and soil moisture were lower in control than in gaps. Seedling survival was high in all gaps regardless of species and season. Seedlings showed higher diameter growth in rectangular than in circular gaps. Research highlights: Austrocedrus chilensis and N. dombeyi seedlings survival is high and their growth slightly affected, when planted in differently-sized canopy gaps within a Pinus contorta plantation in Patagonia. However, other gap sizes and stand densities should be tested before recommending which one shows better results for reconverting monocultures into former native forests. Abbreviations used: PAR (Photosynthetic Active Radiation); DBH (Diameter at Breast Height); INTA (Argentinean Institute of Agricultural Technology); IFONA (Argentinean Forest Institute). (Author)

An elastic lidar system for the H.E.S.S. Experiment

Energy Technology Data Exchange (ETDEWEB)

Bregeon, J.; Compin, M.; Rivoire, S.; Sanguillon, M.; Vasileiadis, G., E-mail: george.vasileiadis@lupm.in2p3.fr

2016-05-21

The H.E.S.S. experiment in Namibia, Africa, is a high energy gamma ray telescope sensitive in the energy range from ~100 Gev to a few tens of TeV, via the use of the atmospheric Cherenkov technique. To minimize the systematic errors on the derived fluxes of the measured sources, one has to calculate the impact of the atmospheric properties, in particular the extinction parameter of the Cherenkov light (~300–650 nm) exploited to observe and reconstruct atmospheric particle showers initiated by gamma-ray photons. A lidar can provide this kind of information for some given wavelengths within this range. In this paper we report on the hardware components, operation and data acquisition of such a system installed at the H.E.S.S. site.

GeV Emission in the Region of HESS J1809‑193 and HESS J1813‑178: Is HESS J1809‑193 a Proton Pevatron?

Science.gov (United States)

Araya, Miguel

2018-05-01

HESS J1809‑193 is an unidentified TeV source discovered by the High Energy Stereoscopic System and originally classified as a pulsar wind nebula (PWN) candidate associated with the pulsar PSR J1809‑1917. However, a recent study of deep radio observations and the interstellar medium near the source has found evidence for a hadronic scenario for the gamma-rays. Here, a detailed study of the GeV emission in the region using data from the Fermi-LAT is presented. The GeV emission has an extended morphology in the region of the TeV emission and the overall spectrum can be accounted for by a cosmic-ray population having a simple power-law spectrum with energies extending up to 1 PeV. However, the spectrum at tens of TeV should be observed more deeply in the future to confirm its hadronic nature, and other scenarios involving combinations of leptonic and hadronic emission from several of the known supernova remnants in the region cannot be ruled out. The nearby TeV source HESS J1813‑178, thought to be a PWN, is also studied in detail at GeV energies and we find a region of significant emission that is much more extended than the TeV emission and whose spectrum is softer than expected from a PWN but similar to those seen in several star-forming regions that are believed to accelerate protons. There is marginal evidence for a GeV point source at the location of the X-ray PWN, beside the extended emission.

Variation in the proximate composition and fatty acid profile recovered from Argentine hake (Merluccius hubbsi) waste from Patagonia

Energy Technology Data Exchange (ETDEWEB)

Cretton, M.; Rost, E.; Mazzuca-Sobczuk, T.; Mazzuca, M.

2016-07-01

The fish processing operations in Patagonia produce large amounts of waste. The main fishery resource in Argentina is the Argentine hake (Merluccius hubbsi). The ports of the province of Chubut (the most important of which are Puerto Madryn, Rawson and Comodoro Rivadavia), together with Caleta Paula Port (province of Santa Cruz), in the Argentine Patagonia, capture more than 82,000 tons of hake annualy, 80% of which are of M. hubbsi, which is mostly converted into fillets. From this capture, about 2,296 tons of liver would be available for the extraction of oil. To promote the recovery and industrial use of fish oil, in the present study, we determined the variation in the proximate composition and fatty acid profile of Argentine hake waste from the ports mentioned above at different catch times. Proximate composition was determined according of the Official Methods of Analysis (AOAC). Fatty acid profile was analyzed by gas chromatography of the fatty acid methyl esters (FAMEs). A standard mixture of FAMEs was run under identical conditions to identify the compounds on the basis of their retention times. Fatty acids were quantified using heptadecanoic acid (C17:0) as internal standard. The highest lipid recovery (27.0 to 41.8% of total lipids) was obtained from the liver fraction. Palmitic acid (C16:0), oleic acid (18:1 n9), docosahexaenoic acid (22:6 n3), eicosapentaenoic acid (20:5 n3) and palmitoleic acid (16:1) were the main constituents. Protein levels in viscera without livers (V-L) were higher than those in the liver. The extraction of marine fish oil and the production of fish offal meal from waste from fish factories would contribute to the sustainability of the regional industry, because it would also decrease the volume of waste, with benefits to the environment. (Author)

Optimization of H.E.S.S. instrumental performances for the analysis of weak gamma-ray sources: Application to the study of HESS J1832-092

International Nuclear Information System (INIS)

Laffon, H.

2012-01-01

H.E.S.S. (High Energy Stereoscopic System) is an array of very-high energy gamma-ray telescopes located in Namibia. These telescopes take advantage of the atmospheric Cherenkov technique using stereoscopy, allowing to detect gamma-rays between 100 GeV and a few tens of TeV. The location of the H.E.S.S. telescopes in the Southern hemisphere allows to observe the central parts of our galaxy, the Milky Way. Tens of new gamma-ray sources were thereby discovered thanks to the galactic plane survey strategy. After ten years of fruitful observations with many detections, it is now necessary to improve the detector performance in order to detect new sources by increasing the sensitivity and improving the angular resolution. The aim of this thesis consists in the development of advanced analysis techniques allowing to make sharper analysis. An automatic tool to look for new sources and to improve the subtraction of the background noise is presented. It is optimized for the study of weak sources that needs a very rigorous analysis. A combined reconstruction method is built in order to improve the angular resolution without reducing the statistics, which is critical for weak sources. These advanced methods are applied to the analysis of a complex region of the galactic plane near the supernova remnant G22.7-0.2, leading to the detection of a new source, HESS J1832-092. Multi-wavelength counterparts are shown and several scenarios are considered to explain the origin of the gamma-ray signal of this astrophysical object. (author)

Is the prominent ericoid mycorrhizal fungus Rhizoscyphus ericae absent in the Southern Hemisphere’s Ericaceae? A case study on the diversity of root mycobionts in Gaultheria spp. from northwest Patagonia, Argentina

Czech Academy of Sciences Publication Activity Database

Brusone, M. C.; Fontenla, S. B.; Vohník, Martin

2015-01-01

Roč. 25, č. 1 (2015), s. 25-40 ISSN 0940-6360 R&D Projects: GA MŠk 7AMB12AR014 Institutional support: RVO:67985939 Keywords : ericoid mycorrhiza * Gaultheria * Patagonia Subject RIV: EF - Botanics Impact factor: 3.252, year: 2015

División social del espacio residencial y migraciones: El caso de San Carlos de Bariloche, Argentina

Directory of Open Access Journals (Sweden)

Brenda Matossian

2015-09-01

Full Text Available El espacio intraurbano en las ciudades contemporáneas de América Latina acusa profundas divisiones sociales, dado el tipo de desarrollo que han tenido bajo los modelos neoliberales imperantes. En este artículo se analiza la ciudad como parte de un devenir histórico-político particular, desde un enfoque multidimensional en el que se hace especial énfasis en la relación establecida entre las divisiones territoriales internas y el componente migratorio de la población. San Carlos de Bariloche (Patagonia argentina posee una heterogénea composición étnico-cultural, fruto de diversos flujos migratorios internos e internacionales. Profundas y complejas distancias materiales y simbólicas separan la ciudad turística (la "Suiza argentina" asociada a una elite nutrida por migrantes internos urbanos y europeos, de la ciudad de "El Alto", donde migrantes internos rurales y chilenos se han asentado en barrios populares. La relación clase-origen se entrelaza en una división social del espacio residencial, que se profundiza y produce segregación urbana y refuerza las tensiones.

Checklist of the Discomycetes (Fungi of Patagonia, Tierra del Fuego and adjacent antarctic areas

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Irma J. Gamundí

2004-01-01

Full Text Available La información brindada en este catálogo consiste en registrar las especies de hongos pertenecientes a los órdenes Cyttariales, Helotiales, Ostropales, Pezizales, Rhytismatales y Thelebolales (Discomycetes coleccionadas en Patagonia, Tierra del Fuego y áreas adyacentes antárticas (Patagonia. Además datos sobre sus organismos asociados fueron localizados, resumidos, validados y editados. Las fuentes de información fueron las exsiccatae depositadas en colecciones de Argentina y otros países y de las publicaciones listadas en la bibliografía. Otros registros derivaron de observaciones de campo sobre material fresco y colecciones de referencia. La información fue acumulada en un sistema computarizado relacional de datos taxonómicos, nomenclaturales, bibliográficos, de distribución geográfica y de observaciones biológicas. Este sistema permite la acumulación de datos paralelos en diferentes idiomas, y distingue la información original de la opinión corriente de lo que puede significar esa información. En la Biological Records Database, 5029 registros fueron creados para observaciones sobre la ocurrencia temporal y espacial de los organismos vivos de la región. De éstos, 2613 corresponden a registros de colecciones de Discomycetes de la Patagonia y Tierra del Fuego, con la siguiente distribución: 1854 para a la Argentina, 687 para Chile y 72 para áreas adyacentes antárticas. Excluyendo los sinónimos, los Discomycetes están representados por 361 especies y taxones subespecíficos (160 géneros, 22 familias y 7 órdenes. Los registros remanentes fueron de organismos asociados con los Discomycetes: 163 animales (8 especies, 8 géneros, 6 familias y 5 órdenes; 2 Chromista; 223 hongos (52 especies, 54 géneros, 26 familias y 13 ódenes; 2028 plantas (159 especies, 122 géneros, 59 familias y 39 órdenes. Cada uno de estos taxones (y cada sinónimo conocido está representado por un registro separado en la Base de Datos Taxon

Distribución de macroinvertebrados (Plecoptera y Aeglidae en ecosistemas fluviales de la Patagonia chilena: ¿Muestran señales biológicas de la evolución geomorfológica postglacial? Distribution of macroinvertebrates (Plecoptera and Aeglidae in fluvial ecosystems of the Chilean Patagonia: Do they show biological signals of the postglacial geomorphological evolution?

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CLAUDIO VALDOVINOS

2010-06-01

Full Text Available La Patagonia chilena incluye uno de los sistemas hídricos más complejos de Sudamérica y uno de los menos intervenidos del mundo, los cuales fueron intensamente modelados por la actividad glacial del Cuaternario. El objetivo de este estudio fue determinar si en esta área existen zonas de endemismo de macroinvertebrados bentónicos fluviales y analizar los patrones de diversidad de organismos de alta (Plecoptera y baja vagilidad (Aeglidae. Entre el 2006 y 2009 se muestrearon 183 sitios entre 42°50' y 54°43' S, focalizándose en las principales cuencas. Los muéstreos se realizaron con una red "kicknet", cubriendo una superficie de fondo de 8 m². En toda el área se registraron 30 especies de Plecoptera y dos de Aeglidae. Se identificó una zona de endemismo en la cuenca del río Aysén, sustentada por el plecóptero Ceratoperla fazi y el cangrejo Aegla neuquensis. Esta última especie correspondería a una población relictual procedente de los ríos de la estepa Argentina, que habría quedado atrapada en la Patagonia chilena, luego que se invirtiera el flujo del cauce del río que originalmente fluía hacia el Atlántico. Un marcado cambio latitudinal en la diversidad de especies fue evidente a lo largo del área de estudio (R² = 0.72, P The Chilean Patagonia includes one of the most complex hydrological systems of South America and one of the least modified systems of the world. These systems were intensely modified by the glacial activity of the Quaternary. The objectives of this study were to determine whether or not in this area exists zones of endemic benthic fluvial macroinvertebrates, and to analyze the patterns of diversity of species composed by organisms of high (Plecoptera and low (Aeglidae vagility. A collection of 183 selected sites, located between the latitude 42° 50' and 54°43' S, were sampled during 2006 and 2009. The sampling was focused on the main river basins and a "kicknet" was used to cover a surface of 8 m² at

Rock Magnetic Properties of Laguna Carmen (Tierra del Fuego, Argentina): Implications for Paleomagnetic Reconstruction

Science.gov (United States)

Gogorza, C. G.; Orgeira, M. J.; Ponce, F.; Fernández, M.; Laprida, C.; Coronato, A.

2013-05-01

We report preliminary results obtained from a multi-proxy analysis including paleomagnetic and rock-magnetic studies of two sediment cores of Laguna Carmen (53°40'60" S 68°19'0" W, ~83m asl) in the semiarid steppe in northern Tierra del Fuego island, Southernmost Patagonia, Argentina. Two short cores (115 cm) were sampled using a Livingstone piston corer during the 2011 southern fall. Sediments are massive green clays (115 to 70 cm depth) with irregularly spaced thin sandy strata and lens. Massive yellow clay with thin sandy strata continues up to 30 cm depth; from here up to 10 cm yellow massive clays domain. The topmost 10 cm are mixed yellow and green clays with fine sand. Measurements of intensity and directions of Natural Remanent Magnetization (NRM), magnetic susceptibility, isothermal remanent magnetization, saturation isothermal remanent magnetization (SIRM), back field and anhysteretic remanent magnetization at 100 mT (ARM100mT) were performed and several associated parameters calculated (ARM100mT/k and SIRM/ ARM100mT). Also, as a first estimate of relative magnetic grain-size variations, the median destructive field of the NRM (MDFNRM), was determined. Additionally, we present results of magnetic parameters measured with vibrating sample magnetometer (VSM). The stability of the NRM was analyzed by alternating field demagnetization. The magnetic properties have shown variable values, showing changes in both grain size and concentration of magnetic minerals. It was found that the main carrier of remanence is magnetite with the presence of hematite in very low percentages. This is the first paleomagnetic study performed in lakes located in the northern, semiarid fuegian steppe, where humid-dry cycles have been interpreted all along the Holocene from an aeolian paleosoil sequence (Orgeira et el, 2012). Comparison between paleomagnetic records of Laguna Carmen and results obtained in earlier studies carried out at Laguna Potrok Aike (Gogorza et al., 2012

DISSECTING THE REGION OF 3EG J1837-0423 AND HESS J1841-055 WITH INTEGRAL

International Nuclear Information System (INIS)

Sguera, V.; Masetti, N.; Bassani, L.; Romero, G. E.; Bazzano, A.; Bird, A. J.

2009-01-01

3EG J1837-0423 and HESS J1841-055 are two unidentified and peculiar high-energy sources located in the same region of the sky, separated by ∼1.4 deg. Specifically, 3EG J1837-0423 is a transient MeV object detected by EGRET only once during flaring activity that lasted a few days while HESS J1841-055 is a highly extended TeV source. We attempted to match the high-energy emission from the unidentified sources 3EG J1837-0423 and HESS J1841-055 with X-rays (4-20 keV) and soft γ-rays (20-100 keV) candidate counterparts detected through deep International Gamma-Ray Astrophysics Laboratory observations of the sky region. As a result we propose the Supergiant Fast X-ray Transient (SFXT) AX J1841.0-0536 as a possible candidate counterpart of 3EG J1837-0423, based on spatial proximity and transient behavior. Alternatively, AX J1841.0-0536 could be responsible for at least a fraction of the entire TeV emission from the extended source HESS J1841-055, based on a striking spatial correlation. In either case, the proposed association is also supported from an energetic standpoint by a theoretical scenario where AX J1841.0-0536 is a low magnetized pulsar which, due to accretion of massive clumps from the supergiant companion donor star, undergoes sporadic changes to transient Atoll-states where a magnetic tower can produce transient jets and as a consequence high-energy emission. In either case (by association with 3EG J1837-0423 or alternatively with HESS J1841-055), AX J1841.0-0536 might be the prototype of a new class of Galactic transient MeV/TeV emitters.

Quantifying mass balance processes on the Southern Patagonia Icefield

DEFF Research Database (Denmark)

Schaefer, M.; Machguth, Horst; Falvey, M.

2015-01-01

We present surface mass balance simulations of the Southern Patagonia Icefield (SPI) driven by downscaled reanalysis data. The simulations were evaluated and interpreted using geodetic mass balances, measured point balances and a complete velocity field of the icefield for spring 2004. The high m...

Sedimentología y estratigrafía de alta resolución del subgrupo río Neuquén (Cretácico Superior) departamento confluencia, provincia de Neuquén, Argentina

OpenAIRE

Sánchez,María Lidia; Asurmendi,Estefanía; Armas,Paula

2014-01-01

En el sector centro-este de la cuenca Neuquina, suroeste de Neuquén, Patagonia Argentina, el Subgrupo Río Neuquén de origen continental ha sido dividido en dos secuencias estratigráficas incompletas (SI y SII) sobre la base de discontinuidades que limitan arreglos de litofacies y elementos arquitecturales característicos. Parte de la sucesión (Formación Portezuelo-SI), se formó a partir de sistemas fluviales de baja y alta sinuosidad que drenaban hacia el noreste. La acreción lateral y oblicu...

Relaciones polen-vegetación de algunos taxa de la estepa patagónica (Argentina Pollen-vegetation relationships of some taxa from the Patagonian steppe (Argentina

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LIDIA S. BURRY

2001-06-01

Full Text Available La aplicación de un análisis de regresión lineal simple a datos de lluvia de polen y de vegetación, en una zona de la Patagonia (Provincia de Chubut, Argentina permitió relacionar cuantitativamente los porcentajes de lluvia polínica y de cobertura de la vegetación para los taxa Poaceae, Papilionoideae, tipo Senecio y Mulinum spinosum. Se obtuvo un buen ajuste de las rectas de regresión para cada uno de los taxa considerados, con coeficientes de correlación r de Pearson altos para M. spinosum (0,82 y tipo Senecio (0,81 y coeficientes algo menores en el caso de Poaceae (0,66 y Papilionoideae (0,61. Estas regresiones permitieron inferir la presencia o ausencia de polen regional y el valor predictivo de la presencia de polen en ausencia de la vegetación que lo produce. Al respecto, la lluvia de polen estudiada incluye el aporte regional (excepto Papilionoideae aun cuando M. spinosum tiene una baja contribución. Esta sobrerrepresentación es atribuible al transporte de larga distancia, a través de los vientos que provienen del oeste. Estas relaciones cuantitativas nos permitirán extrapolar cambios vegetacionales pasados en estos taxa a partir de espectros de polen fósil para el área de estudioThe use of simple linear regression to data of pollen rain and vegetation cover in Patagonia (Province of Chubut, Argentina allowed us to develop quantitative relationships between modern pollen rain perecentages and vegetation cover for the taxa Poaceae, Papilionoideae, Senecio type, and Mulinum spinosum. The analysis revealed a good fit of data to regression lines for all taxa, with high Pearson r coefficient values in the case of M. spinosum (0.82 and Senecio type (0.81, and somewhat lower values in the case of Poaceae (0.66 and Papilionoideae (0.61. These regressions allowed us to infer the presence or absence of regional pollen and predict the quantity of pollen in the absence of the vegetation producing it. In this regard, the studied pollen

Genetic characterization of human hydatid cysts shows coinfection by Echinococcus canadensis G7 and Echinococcus granulosus sensu stricto G1 in Argentina.

Science.gov (United States)

Debiaggi, María Florencia; Soriano, Silvia Viviana; Pierangeli, Nora Beatriz; Lazzarini, Lorena Evelina; Pianciola, Luis Alfredo; Mazzeo, Melina Leonor; Moguillansky, Sergio; Farjat, Juan Angel Basualdo

2017-09-01

Human cystic echinococcosis caused by the larval stage of Echinococcus granulosus sensu lato (s.l.) is a highly endemic disease in the province of Neuquén, Patagonia, Argentina. Human infections with E. granulosus sensu stricto (s.s.) G1 and Echinococcus canadensis G6 were reported in Neuquén in previous studies, whereas four genotypes were identified in livestock: G1, G3, G6, and G7. The aim of this study was to identify the genotypes of E. granulosus s.l. isolates from humans of Neuquén province, Patagonia, Argentina, through the 2005-2014 period. Twenty six hydatid cysts were obtained from 21 patients. The most frequent locations were the liver and lungs. Single cysts were observed in 81.0% of patients, and combined infection of liver and lungs was detected in 9.5% of cases. Partial sequencing of mitochondrial cytochrome c oxidase subunit 1 (cox1) and NADH dehydrogenase subunit 1 (nad1) genes identified the presence of E. granulosus s.s. G1 (n = 11; 42.3%) including three different partial sequences; E. canadensis G6 (n = 14; 53.8%) and E. canadensis G7 (n = 1; 3.9%). Coinfection with G1 and G7 genotypes was detected in one patient who harbored three liver cysts. Most of the liver cysts corresponded to G1 and G6 genotypes. This study presents the first report in the Americas of a human infection with E. canadensis G7 and the second worldwide report of a coinfection with two different species and genotypes of E. granulosus s.l in humans. The molecular diversity of this parasite should be considered to redesign or improve the control program strategies in endemic regions.

Where Are Our Greenfields?: A Conversation with Frederick M. Hess

Science.gov (United States)

Perkins-Gough, Deborah

2010-01-01

In an interview with Educational Leadership, Frederick M. Hess talks about greenfield schooling--a policy approach that attempts to knock down the formal and informal barriers that stand in the way of innovation in education. Greenfield schooling, he explains, "doesn't imagine that we should go around razing districts or schools or taking…

Diet composition and feeding habits of the eyespot skate, Atlantoraja cyclophora (Elasmobranchii: Arhynchobatidae, off Uruguay and northern Argentina

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Santiago A. Barbini

Full Text Available ABSTRACT The eyespot skate, Atlantoraja cyclophora, is an endemic species from the southwestern Atlantic, occurring from Rio de Janeiro, Brazil, to northern Patagonia, Argentina. The feeding habits of this species, from off Uruguay and north Argentina, were evaluated using a multiple hypothesis modelling approach. In general, the diet was composed mainly of decapod crustaceans, followed by teleost fishes. Molluscs, mysidaceans, amphipods, isopods, lancelets and elasmobranchs were consumed in lower proportion. The consumption of shrimps drecreased with increasing body size of A. cyclophora. On the other hand, the consumption of teleosts increased with body size. Mature individuals preyed more heavily on crabs than immature individuals. Teleosts were consumed more in the south region (34º - 38ºS and crabs in the north region (38º - 41ºS. Shrimps were eaten more in the warm season than in the cold season. Prey size increased with increasing body size of A. cyclophora , but large individuals also consumed small teleosts and crabs. Atlantoraja cyclophora has demersal-benthic feeding habits, shifts its diet with increasing body size and in response to seasonal and regional changes in prey availability and distribution.

Peasant territoriality in the South of Argentina. Productive and labour changes as forms of resistance

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Mónica Bendini

2014-03-01

Full Text Available In a context of territorial expansion of capital and social changes in rural life, the article addresses the issue of the persistence of peasant producers in northern Patagonia (Argentina and the development of various adaptive strategies as a form of resistance expulsion as producers. The changes are researched not only in households but also in the areas of life and work of those producers who call themselves "crianceros" in two regions of extensive livestock export oriented, wool and mohair hair. The cases show that the territorial expansion of capital involves social dynamics that go beyond productive and institutional transformations. Family strategies are more complex and also generate changes in other levels of rurality, in the mobility, in the habitat, in the activities of the countryside and towns, in the horizons of rural life. 

Argentina against the Allende government, the look of daily Río Negro

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Alfredo Azcoitia

2017-05-01

Full Text Available In the present article we address the news about the Argentine-Chilean ties that circulated through the most influential newspaper of Argentine Norpatagonia during the years of the government of Salvador Allende (1970-1973. Through the tools of discourse analysis we realize the multiple dimensions that conditioned the discourses as well as the meanings acquired by binational relations within the framework of the discourses. We consider that this type of studies contributes to deconstruct the essential glances over the other, giving account of the several edges contained in the representations that circulate through the press. This acquires greater relevance in the case of the Northern Patagonia, it is in a region whose links with Chile set up an as historical as everyday experience In this sense, the discourses that prevailed in the Río Negro built a Chile Its past and present intimately linked it to the future of Argentina and the region.

Helminth communities of two populations of Myotis chiloensis (Chiroptera: Vespertilionidae from Argentinean Patagonia

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Antonella C. Falconaro

2018-04-01

Full Text Available Most of the studies on chiropteran endoparasites in Argentina come from the Central and Northeast regions of the country, and there is only one parasitological study of bats from the Argentinean Patagonia. The aim of this study is to describe the helminth fauna of 42 Myotis chiloensis, comparing the composition and the structure of the endoparasite communities between two populations, inhabiting different environments in Andean humid forest and the ecotone between forest and Patagonian steppe. A total of 697 helminths were recovered from 33 bats: five species of trematodes, Ochoterenatrema sp., Paralecithodendrium sp., Parabascus limatulus, Parabascus sp., and Postorchigenes cf. joannae, two species of cestodes, Vampirolepis sp. 1 and Vampirolepis sp. 2, and three species of nematodes, Allintoshius baudi, Physaloptera sp., and Physocephalus sp. All the helminths, but Physocephalus sp., were recovered from the small and large intestine. This is the first survey of M. chiloensis’ helminth fauna. All the species, but A. baudi, represent new records of helminths in Patagonian bats. There were differences of parasite species richness between localities and both bat populations share almost half of the endoparasite species. Different preferences for intestinal regions were found for three species of trematodes in the bats from the site in the humid forest. Myotis chiloensis serves as both a definitive and intermediate host for endoparasites in the Patagonian ecosystem. Keywords: Bats, Parasites, South America

Unravelling the collapse mechanisms at a Jurassic caldera of the Chon Aike silicic LIP in Southern Patagonia (47 deg. 15 'S, 71 deg. 40'W), Argentina

Energy Technology Data Exchange (ETDEWEB)

Sruoga, P [CONICET-SEGEMAR. Av. J. A. Roca 651. Buenos Aires (Argentina); Japas, S; Salani, F [CONICET-UBA. Depto. Cs. Geologicas, Pabellon II, Ciudad Universitaria, C1428EHA, Buenos Aires (Argentina); Kleiman, L [Gerencia de Exploration de Materias Primas, Comision Nacional de EnergIa Atomica, Avda. del Libertador 8250, 1419, Buenos Aires (Argentina); Graffigna, M [Universidad Nacional de San Juan (Argentina)], E-mail: patysruoga@yahoo.com.ar, E-mail: msjapas@gl.fcen.uba.ar, E-mail: fms@gl.fcen.uba.ar, E-mail: kleiman@cae.cnea.gov.ar

2008-10-01

La Peligrosa Caldera is located at Sierra Colorada (47{sup 0} 15'S, 71{sup 0} 40' W) in the Chon-Aike silicic LIP. It represents an unique window to understand the eruptive mechanisms that prevailed throughout the ignimbritic flare-up in Southern Patagonia during middle to late Jurassic times. Key pieces of lithologic and structural evidences are taken into account to reconstruct the volcanic structure.

The role of natural mineral particles collected at one site in Patagonia as immersion freezing ice nuclei

Science.gov (United States)

López, María Laura; Borgnino, Laura; Ávila, Eldo E.

2018-05-01

This work studies the role of mineral particles collected in the region of Patagonia (Neuquén, Argentina) as ice nuclei particles (INPs) by immersion freezing mode. The particle immersion-freezing ability was analyzed under laboratory conditions by using an established drop-freezing technique. Mineralogical composition was characterized by using X-ray diffraction and electron micro probe analysis. Dynamic light scattering was used to determine the grain size distribution of particles, while the N2 adsorption and methylene blue adsorption methods were applied to determine their specific surface area. Water droplets of different volumes containing different concentrations of particles were cooled until droplets were frozen. For all the analyzed drop volumes, an increase in the freezing temperature of the drops was observed with increasing dust concentration. In the same way, the freezing temperature increased when the drop volume was increased at constant dust concentration. Both behaviors were linked to the availability of active sites in the particles. A plateau in the freezing temperature was observed at high suspension concentration for all the drop volumes. This plateau was related to the aggregation of the particles when the suspension concentration was increased and to the consequent decrease in the number of active sites. The active sites per unit of surface area were calculated and reported. For the studied range of temperature, results are in agreement with those reported for different sites and particles. From the chemical and morphological analysis of the particle components and the results obtained from the literature, it was concluded that even though montmorillonite was the main mineral in the collected sample, the accessory minerals deserve to be analyzed in detail in order to know if they could be responsible for the ability of the collected soil particles to act as INPs. Considering that the region of Patagonia has been identified as an important

Análisis de sistema de conversores fluido-dinámicos de energía renovable para la Patagonia Austral de Argentina

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Carlos Victor Manuel Labriola

2014-06-01

Full Text Available El potencial de energía en mares y océanos se puede clasificar de distintas formas, por ejemplo: * La energía de las mareas ó Mareomotriz * La energía de las corrientes marinas * La energía de las olas ó Undimotriz * La energía térmica oceánica (OTEC. De estas formas de energía oceánica, tres son posibles en la zona Atlántica de nuestra Patagonia Austral, la Mareomotriz, la Undimotriz y la de corrientes marinas. La Energía Mareomotriz se da desde Viedma hasta Tierra del Fuego con amplitudes de mareas de 4m hasta 20m, la Energía de las Olas se da en la costa de Chubut y Santa Cruz con potenciales de 10 a 30kW/m lineal de frente de ola y el aprovechamiento de las corrientes marinas se puede dar en lugares puntuales como ser la desembocadura del río Deseado o la de Río Gallegos. Para estas Fuentes de Energía se está realizando un banco de pruebas de modelos conversores de las mismas a Energía Eléctrica, en la Unidad Académica Caleta Olivia (UACO de la Universidad Nacional de la Patagonia Austral (UNPA. Este banco dispondrá de dos canales de ensayos hidrodinámicos uno para energía de las corrientes marinas y otro para las olas. El primero dispondrá de una bomba de circulación con velocidad de fluido variable entre 0 y 4m/s. El banco para olas tendrá un sistema de batido del agua para producir ondas de amplitud y período variable. Además se están dimensionando dos modelos de conversores de energía oceánica. Uno es una turbina, tipo eólica sumergida y el otro modelo es de tubo electromecánico oscilante como conversor energético de las olas.

Plantas Medicinales en el Parque Nacional los alerces, Chubut, Patagonia Argentina

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Carolina Toledo

2012-12-01

Full Text Available El objetivo de este estudio fue identificar las plantas con valor medicinal empleadas por los antiguos pobladores del Parque Nacional Los Alerces y relacionarlas con la riqueza específica de plantas medicinales presentes en el área. Se entrevistaron 16 pobladores asentados en la Reserva Nacional que tenían conocimiento de las plantas medicinales, más allá de que hicieran uso o no de las mismas. Las entrevistas fueron semiestructuradas, completadas de manera escrita e individual por el entrevistador. Las mismas incluían diez preguntas que recopilaban información respecto a las especies usadas como medicina, modo de preparación y aplicación, frecuencia de uso, localización de las plantas en el ámbito del área protegida, forma de obtención de las especies, y el modo de adquisición de los conocimientos respecto a las plantas. Los pobladores mencionaron el uso de 42 especies con valor medicinal, distribuidas en 24 familias, de las cuales las mejor representadas fueron Lamiaceae (21,4% y Asteraceae (14,2%. En cuanto al origen de las plantas medicinales citadas por los pobladores, el 58, 5% correspondió a especies exóticas. Los usos más frecuentes fueron para trastornos del sistema digestivo, seguido en orden decreciente y en menor proporción para tratar afecciones respiratorias, cardiovasculares y de la piel. Al comparar la riqueza total de especies medicinales presentes en el Parque y las registradas a partir de las entrevistas, se observa que se hace uso de un 28,6% de lo disponible en el área.Medicinal plants in The Alerces National Park, Chubut, Argentinean Patagonia. The aim of this study was to identify the medicinal plants used by the old residents in The Alerces National Park and to relate this information with medicinal species richness in the area. An interview was employed with 16 local people settled in the National Reserve who had knowledge of medicinal plants, past or not to make use of them. The interviews were semi

New records of water mites (Acari: Hydrachnidia, Halacaroidea) from Patagonia (Chile)

NARCIS (Netherlands)

Pešić, V.; Smit, H.; Datry, T.

2010-01-01

New records of water mite species (Acari: Hydrachnidia, Halacaroidea) from Patagonia (Southern Chile) are reported. Four species, Anisitsiellides australis Smit, 2002, Peregrinacarus falklandensis Bartsch, 2001, Lobohalacarus weberi (Romijn & Viets, 1924) and Soldanellonyx monardi Walter, 1919 are

Dietary analysis of Homonota darwini (Squamata: Gekkoni-dae in Northern Patagonia

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Marcelo E. KUN, Carla PIANTONI, John D. KRENZ, Nora R. IBARGÜENGOYTÍA

2010-08-01

Full Text Available Our study investigated the diet of the southernmost gecko in the world, Homonota darwini. Fifty-three specimens were captured during spring and summer in four locations in Patagonia, Argentina. The stomach contents of the specimens were identified, and we found that prey consisted of six main groups: Coleoptera, Hymenoptera, Homoptera and Araneae, and the adults and larvae of moth Lepidoptera. Lepidoptera was the major dietary component. The presence of ants and moths as common prey suggests an ambush feeding strategy. In spring, females consumed more ants than males although no other dietary differences between males and females were evident. We found nine geckos with empty stomachs and six parasitized by nematodes. Presence of empty stomachs corroborates previous observations of other nocturnal geckos and non-gecko lizards. Reduced foraging success of nocturnal lizards could be due to difficulty in prey detection due to dim light, reduced or erratic activity of insect prey at night, or shorter activity times of geckos relative to diurnal success. Sex and season were not associated with the incidence of empty stomachs. Principal component analysis showed that four food alternatives correlated with season. The constraint of nocturnality, coupled with low night-time temperatures restricting feeding to only a few hours after sunset, appear to have caused a generality of diet which may limit energy acquisition. We conclude that H. darwini is an arthropod generalist and likely an ambush forager, as are many other nocturnal gekkonids [Current Zoology 56 (4: 406–410, 2010].

A NEW TeV BINARY: THE DISCOVERY OF AN ORBITAL PERIOD IN HESS J0632+057

International Nuclear Information System (INIS)

Bongiorno, S. D.; Falcone, A. D.; Stroh, M.; Holder, J.; Skilton, J. L.; Hinton, J. A.; Gehrels, N.; Grube, J.

2011-01-01

HESS J0632+057 is a variable, point-like source of very high energy (>100 GeV) gamma rays located in the Galactic plane. It is positionally coincident with a Be star, it is a variable radio and X-ray source, has a hard X-ray spectrum, and has low radio flux. These properties suggest that the object may be a member of the rare class of TeV/X-ray binary systems. The definitive confirmation of this would be the detection of a periodic orbital modulation of the flux at any wavelength. We have obtained Swift X-Ray Telescope observations of the source from MJD 54857 to 55647 (2009 January-2011 March) to test the hypothesis that HESS J0632+057 is an X-ray/TeV binary. We show that these data exhibit flux modulation with a period of 321 ± 5 days and we evaluate the significance of this period by calculating the null hypothesis probability, allowing for stochastic flaring. This periodicity establishes the binary nature of HESS J0632+057.

Ploidy levels and reproductive behaviour in invasive Hieracium pilosella in Patagonia

Czech Academy of Sciences Publication Activity Database

Krahulec, František; Krahulcová, Anna

2011-01-01

Roč. 11, - (2011), s. 25-31 ISSN 1619-0033 R&D Projects: GA ČR GA206/08/0890 Institutional research plan: CEZ:AV0Z60050516 Keywords : Patagonia * ploidy levels * hybridization Subject RIV: EF - Botanics

Back-arc basalts from the Loncopue graben (Province of Neuquen, Argentina)

Science.gov (United States)

Varekamp, J. C.; Hesse, A.; Mandeville, C. W.

2010-11-01

Young basaltic back-arc volcanoes occur east of the main Andes chain at about 37.5°-39°S in the Loncopue graben, Province of Neuquen, Argentina. These olivine-rich basalts and trachybasalts have up to 8% MgO, with high Ni and Cr contents, but highly variable incompatible element concentrations. Mafic lava flows and cinder cones at the southern end of the graben lack phenocrystic plagioclase. The northern samples have relative Ta-Nb depletions and K, Pb and LREE enrichment. These samples strongly resemble rocks of the nearby arc volcanoes Copahue and Caviahue, including their Fe-Ti enrichment relative to the main Andes arc rocks. The Sr, Nd and Pb isotope ratios show that the source regions of these back-arc basalts are enriched in subducted components that were depleted in the aqueous mobile elements such as Cs, Sr and Ba as a result of prior extractions from the subducted complex below the main arc. Some mafic flows show slightly low 206Pb/ 204Pb and 143Nd/ 144Nd values as well as incompatible trace element ratios similar to southern Patagonia plateau back-arc basalts, suggesting contributions from an EM1 mantle source. Geothermometry and barometry suggest that the basalts crystallized and fractionated small amounts of olivine and spinel at ˜ 35 km depth at temperatures of 1170-1220 °C, at about QFM + 0.5 to QFM + 1 with 1-2% H 2O, and then rose rapidly to the surface. The Loncopue graben back-arc basalts are transitional in composition between the South Patagonia back-arc plateau basalts and the Caviahue and Copahue arc volcanoes to the northwest. The EM1 source endmember is possibly the subcontinental lithospheric mantle. Strong variations in incompatible element enrichment and isotopic compositions between closely spaced cinder cones and lava flows suggest a heterogeneous mantle source for the Loncopue graben volcanics.

LA PATAGONIA COMO TERRITORIO EN DISPUTA: TENSIONES ENTRE EL ESTADO, LA IGLESIA Y LA CONGREGACIÓN SALESIANA POR EL ESPACIO MISIONERO

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María Nicoletti

2012-06-01

Full Text Available La Patagonia fue el primer territorio salesiano “ad gentes”. La creación de su administración bajo la figura de un Vicariato y Prefectura apostólica de parte de la Congregación Salesiana y el Colegio de Propaganda Fide, trajo aparejados numerosos conflictos con las Iglesias Argentina y Chilena y con ambos Estados nacionales. Estos conflictos, en el marco histórico de la construcción de las naciones del siglo XIX y principios del siglo XX, fueron acompañados por los planes de evangelización que la Congregación salesiana había formulado para los pueblos originarios. Bajo la gestión y dirección de los dos primeros rectores mayores de la Congregación, Don Bosco y Don Rua, se resolvieron los problemas con las Iglesias y Estados de ambas naciones, cargados de tensiones en la construcción del territorio de evangelización considerado según cada institución como “terra nullius”, “territorio salesiano” o “territorio nacional y diocesano”.

Comparison of a new digital KM screen test with conventional Hess and Lees screen tests in the mapping of ocular deviations.

Science.gov (United States)

Thorisdottir, Rannveig Linda; Sundgren, Johanna; Sheikh, Rafi; Blohmé, Jonas; Hammar, Björn; Kjellström, Sten; Malmsjö, Malin

2018-05-28

To evaluate the digital KM screen computerized ocular motility test and to compare it with conventional nondigital techniques using the Hess and Lees screens. Patients with known ocular deviations and a visual acuity of at least 20/100 underwent testing using the digital KM screen and the Hess and Lees screen tests. The examination duration, the subjectively perceived difficulty, and the patient's method of choice were compared for the three tests. The accuracy of test results was compared using Bland-Altman plots between testing methods. A total of 19 patients were included. Examination with the digital KM screen test was less time-consuming than tests with the Hess and Lees screens (P digital KM screen). Patients found the test with the digital KM screen easier to perform than the Lees screen test (P = 0.009) but of similar difficulty to the Hess screen test (P = 0.203). The majority of the patients (83%) preferred the digital KM screen test to both of the other screen methods (P = 0.008). Bland-Altman plots showed that the results obtained with all three tests were similar. The digital KM screen is accurate and time saving and provides similar results to Lees and Hess screen testing. It also has the advantage of a digital data analysis and registration. Copyright © 2018 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

Discursos de alteridad en la dramaturgia regional de la posdictadura argentina

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Mauricio Tossi

2016-01-01

Full Text Available Las secuelas de la última dictadura militar en Argentina se observan en diversos aspectos culturales, entre otros, en la concepción de “alteridad sospechosa” que el régimen instaló en los campos sociales para justificar sus políticas represivas y genocidas. De este modo, con la reapertura democrática, el arte en general y el teatro en particular, asumieron, con responsabilidad estética, la tarea de resignificar aquellos discursos sobre la otredad ominosa legada. Por consiguiente, en el presente artículo abordaremos las respuestas poé- ticas que la dramaturgia regional ha enunciado como estrategias de resistencia, con el fin de aportar a los nuevos procesos comunitarios e intersubjetivos sobre el pasado reciente. Para indagar en este problema, apelaremos a herramientas hermenéuticas de la literatura comparada y la sociología de la cultura, aplicadas al análisis de las obras teatrales de Alejandro Finzi y Carlos María Alsina, escritas en la Patagonia y el noroeste argentinos, en el periodo1983-2003.

Diplodon shells from Northwest Patagonia as continental proxy archives: Oxygen isotopic results and sclerochronological analyses

Science.gov (United States)

Soldati, A. L.; Beierlein, L.; Jacob, D. E.

2009-04-01

Freshwater mussels of the genus Diplodon (Bivalvia, Hyriidae) are the most abundant bivalve (today and in the past) in freshwater bodies at both sides of the South-Andean Cordillera. There are about 25 different Diplodon genera in Argentina and Chile that could be assigned almost completely to the species Diplodon chilensis (Gray, 1828) and two subspecies: D. ch. chilensis and D. ch. patagonicus; this latter species is found in Argentina between Mendoza (32˚ 52' S; 68˚ 51' W) and Chubut (45˚ 51' S; 67˚ 28' W), including the lakes and rivers of the target area, the Nahuel Huapi National Park (Castellanos, 1960). Despite their wide geographic distribution, Diplodon species have only rarely been used as climate archives in the southern hemisphere. Kaandorp et al. (2005) demonstrated for Diplodon longulus (Conrad 1874) collected from the Peruvian Amazonas that oxygen isotopic patterns in the shells could be used in order to reconstruct the precipitation regime and dry/wet seasonal of the monsoonal system in Amazonia. Although this study demonstrated the potential of Diplodon in climatological and ecological reconstructions in the southern hemisphere, as of yet, no systematic study of Diplodon as a multi-proxy archive has been undertaken for the Patagonian region. In this work we present sclerochronological analyses supported by ^18Oshell in recent mussel of Diplodon chilensis patagonicus (D'Orbigny, 1835) collected at Laguna El Trébol (42°S-71°W, Patagonia Argentina), one of the best studied water bodies in the region for paleoclimate analysis. Water temperature was measured every six hours for one year using a temperature sensor (Starmon mini®) placed at 5m depth in the lake, close to a mussel bank. Additionally, ^18Owater was measured monthly for the same time range.g^18Oshell values obtained by micro-milling at high spatial resolution in the growth increments of three Diplodon shells were compared to these records, and to air temperature and

First occurrence of western corn root worm beetles in the federal states Hesse and Rhineland-Palatinate (Germany, 2011

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Dicke, Dominik

2014-02-01

Full Text Available In 2011, western corn root worm beetles were detected in the federal states Hesse (Groß-Gerau and Rhineland-Palatinate (Bodenheim for the first time. Control measures based on commission decision 2003/766/EG (Byrne, 2003 were conducted after detection in PAL-traps. Focus and safety zones were established. In Hesse, both focus and safety zones were treated with the insecticide Biscaya, due to the high number of 50 beetles which were detected in the PAL-traps. Since in Rhineland-Palatinate, only one beetle had been captured, only the focus zone was treated with the insecticide. After insecticide treatment, new PAL-traps were arranged like a close grid over the infested areas in both federal states. In each maize field in the focus- and safety zone further traps were placed and checked weekly until September 30th by supporting staff. Until the end of the monitoring in 2011 (September 30th further beetles were detected in the south of the area (district of Groß-Gerau, Hesse, were the first infestation had been discovered. However, in Rhineland-Palatinate no further beetles were detected that year. By the end of the monitoring 354 beetles in Hesse and one beetle in Rhineland-Palatinate had been captured in total. Subsequently the demarked zones in Hesse were extended. Taking into account the local circumstances, the new focus zone was delimited to include all the areas where beetles had been detected as well as the surrounding maize fields. In the focus zones the cultivation of maize was forbidden for the consecutive two years and a crop rotation with at least 50 percent maize was established in the safety zones. In 2012 no further beetles were captured in the infested region.

Exact decoupling of the Dirac Hamiltonian. II. The generalized Douglas-Kroll-Hess transformation up to arbitrary order

International Nuclear Information System (INIS)

Reiher, Markus; Wolf, Alexander

2004-01-01

In order to achieve exact decoupling of the Dirac Hamiltonian within a unitary transformation scheme, we have discussed in part I of this series that either a purely numerical iterative technique (the Barysz-Sadlej-Snijders method) or a stepwise analytic approach (the Douglas-Kroll-Hess method) are possible. For the evaluation of Douglas-Kroll-Hess Hamiltonians up to a pre-defined order it was shown that a symbolic scheme has to be employed. In this work, an algorithm for this analytic derivation of Douglas-Kroll-Hess Hamiltonians up to any arbitrary order in the external potential is presented. We discuss how an estimate for the necessary order for exact decoupling (within machine precision) for a given system can be determined from the convergence behavior of the Douglas-Kroll-Hess expansion prior to a quantum chemical calculation. Once this maximum order has been accomplished, the spectrum of the positive-energy part of the decoupled Hamiltonian, e.g., for electronic bound states, cannot be distinguished from the corresponding part of the spectrum of the Dirac operator. An efficient scalar-relativistic implementation of the symbolic operations for the evaluation of the positive-energy part of the block-diagonal Hamiltonian is presented, and its accuracy is tested for ground-state energies of one-electron ions over the whole periodic table. Furthermore, the first many-electron calculations employing sixth up to fourteenth order DKH Hamiltonians are presented

Exact decoupling of the Dirac Hamiltonian. II. The generalized Douglas-Kroll-Hess transformation up to arbitrary order.

Science.gov (United States)

Reiher, Markus; Wolf, Alexander

2004-12-08

In order to achieve exact decoupling of the Dirac Hamiltonian within a unitary transformation scheme, we have discussed in part I of this series that either a purely numerical iterative technique (the Barysz-Sadlej-Snijders method) or a stepwise analytic approach (the Douglas-Kroll-Hess method) are possible. For the evaluation of Douglas-Kroll-Hess Hamiltonians up to a pre-defined order it was shown that a symbolic scheme has to be employed. In this work, an algorithm for this analytic derivation of Douglas-Kroll-Hess Hamiltonians up to any arbitrary order in the external potential is presented. We discuss how an estimate for the necessary order for exact decoupling (within machine precision) for a given system can be determined from the convergence behavior of the Douglas-Kroll-Hess expansion prior to a quantum chemical calculation. Once this maximum order has been accomplished, the spectrum of the positive-energy part of the decoupled Hamiltonian, e.g., for electronic bound states, cannot be distinguished from the corresponding part of the spectrum of the Dirac operator. An efficient scalar-relativistic implementation of the symbolic operations for the evaluation of the positive-energy part of the block-diagonal Hamiltonian is presented, and its accuracy is tested for ground-state energies of one-electron ions over the whole periodic table. Furthermore, the first many-electron calculations employing sixth up to fourteenth order DKH Hamiltonians are presented. (c) 2004 American Institute of Physics.

Recent progress on the HESS experiment

International Nuclear Information System (INIS)

Mayo, R.M.; Barnes, D.C.; Freeman, B.; Henins, I.; Jarboe, T.R.; Platts, D.

1990-01-01

The new objective of the Los Alamos spheromak program is to assess the use of magnetized plasmas as an energy transfer medium to accelerate material objects to hyper-velocities (approx-gt 20 km/s). In meeting this objective, the authors are committed to the subordinate goals of (1) creating high field, long-lived spheromak discharges, (2) examining the technical feasibility of employing High Explosives (HE) to compress seed spheromaks, and (3) investigate the technical requirements involved in forming spheromaks by Mechanical Helicity Injection (HMI) using HE. This paper describes the recent efforts of the CTR-5, M-4, and M-6 groups at Los Alamos in assessing the feasibility of generating magnetic helicity by mechanical means in the High Explosive Spheromak Source (HESS) experiment

Disease Management Project Breast Cancer in Hesse - 5-Year Survival Data: Successful Model of Intersectoral Communication for Quality Assurance.

Science.gov (United States)

Jackisch, C; Funk, A; König, K; Lubbe, D; Misselwitz, B; Wagner, U

2014-03-01

Introduction: The Disease Management Project Breast Cancer (DMP Breast Cancer) was first launched in Hesse in 2004. The project is supported by the health insurance companies in Hesse and the Professional Association of Gynaecologists in Hesse. The aim is to offer structured treatment programmes to all women diagnosed with breast cancer in Hesse by creating intersectoral cooperations between coordinating clinics, associated hospitals and gynaecologists in private practice who registered in the DMP programme. Method: Between 1 January 2005 and 30 June 2011, 13 973 women were enrolled in the DMP programme. Results: After data cleansing, survival rates were calculated for a total of 11 214 women. The 5-year overall survival (OS) rate was 86.3 %; survival rates according to tumour stage on presentation were 92.2 % (pT1) and 82.3 % (pT2), respectively. The impact of steroid hormone receptor status on survival (87.8 % for receptor-positive cancers vs. 78.9 % for receptor-negative cancers) and of age at first diagnosis on survival (≤ 35 years = 91 %) were calculated. Conclusion: The project showed that intersectoral cooperation led to significant improvements in the quality of treatment over time, as measured by quality indicators and outcomes after treatment.

Helosis (Balanophoraceae en Argentina Helosis (Balanophoraceae in Argentina

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José Luis Fontana

2006-07-01

Full Text Available Se cita por primera vez para Argentina Helosis cayennensis (Swartz Sprengel var. cayennensis en base a colecciones hechas por los autores en la Isla argentina de Apipé Grande, Ituzaingó, provincia de Corrientes. Se describe e ilustra la especie, el desarrollo de la planta y su estado de conservación. Esta cita de Helosis corresponde a un género nuevo para la flora argentina.Helosis cayennensis var. cayennensis is reported for the first time for Argentina. The species is described and ilustrated. Developement and ecology are also given. Helosis is also a new generic record for Argentina.

Seasonal determination of trace and ultra-trace content in Macrocystis pyrifera from San Jorge Gulf (Patagonia) by Total Reflection X-ray Fluorescence

Science.gov (United States)

Salomone, Vanesa N.; Riera, Marina; Cerchietti, Luciana; Custo, Graciela; Muniain, Claudia

2017-05-01

Seaweed have a great capacity to accumulate heavy metals in their tissues. The chemical characterization of seaweed is important due to their use in environmental monitoring and human or animal food. The aim of the present study was to evaluate the multi-elemental composition of seaweed from San Jorge Gulf (Patagonia, Argentina) by Total Reflection X-ray Fluorescence (TXRF). The elements As, Br, Cu, Cr, Fe, Mn, Ni, Pb, Rb, Sr, V and Zn were seasonally analyzed and quantified in blades of Macrocystis pyrifera. TXRF showed to be a suitable technique for simultaneous multi-element analysis in this kind of samples. The results revealed seasonal variations in the chemical content for some elements; arsenic content was maximum in summer and autumn, iron concentration increased to the winter and zinc concentration was maximum in autumn. The sum of principal micronutrients (Fe + Zn + Mn + Cu) varied between 114 and 171 mg k- 1 g dw. The total As concentration ranged between 36 and 66 mg kg- 1. Lead, nickel and copper were not detected.

Short note on inhomogeneities in the Hess-Brezowsky catalogue of circulation types

Czech Academy of Sciences Publication Activity Database

Cahynová, Monika; Huth, Radan

2007-01-01

Roč. 10, č. 3 (2007), s. 171-174 ISSN 1335-339X R&D Projects: GA MŠk OC 115; GA AV ČR IAA300420506 Institutional research plan: CEZ:AV0Z30420517 Keywords : atmospheric circulation * Hess-Brezowsky classification * homogeneity Subject RIV: DG - Athmosphere Sciences, Meteorology

Hazardous metal pollution in a protected coastal area from Northern Patagonia (Argentina).

Science.gov (United States)

Marinho, C H; Giarratano, E; Esteves, J L; Narvarte, M A; Gil, M N

2017-03-01

The San Antonio Bay is a protected natural coastal area of Argentina that has been exposed to mining wastes over the last three decades. Iron and trace metals of potential concern to biota and human health (Cd, Pb, Cu, and Zn) were investigated in the sediments from the bay and in the soils of the Pile (mining wastes). Concentrations of Cd (45 mg kg -1 ), Pb (42,853 mg kg -1 ), Cu (24,505 mg kg -1 ), and Zn (28,686 mg kg -1 ) in the soils Pile exceeded guidelines for agricultural, residential, and industrial land uses. Risk assessment due to exposure to contaminated soils (Pile) was performed. Hazard quotients were superior to non-risk (HQ >1) for all trace metals, while accumulative hazard quotient index indicated a high risk for children (HI = 93) and moderate for adults (HI = 9). In the bay, sediments closest to the Pile (mudflat and salt marsh) exceeded sediment quality guidelines for protection of biota. Results of different acid extraction methods suggest that most of the pseudototal content was potentially mobile. Principal component analysis indicated that the sites near the Pile (Encerrado channel) were more polluted than the distal ones. Tissues of Spartina spp. located within Encerrado channel showed the highest metal levels among all studied sites. These results show that the problem still persists and the mining wastes are the sources of the pollution. Furthermore, the Encerrado channel is a highly impacted area, as it is shown by their metal enriched sediments.

Mapuche y ranqueles en la Argentina: relatos sobre su pasado y presente

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Graciana Pérez Zavala

2008-07-01

Full Text Available En este artículo se planteo la reconstrucción de los relatos del pasado por parte de indígenas que viven en el territorio argentino, particularmente los mapuche y ronqueles. Para explicar estos variaciones en la interpretación del pasado por parte de las diferentes organizaciones indigenas, se examina la "Conquista del Desierto" (1878-1885, en tanto acontecimiento nodal en la estructuración de las relaciones interétnicas actuales en Argentina. En primer lugar, se sintetizan varios elementos de la historia de los indígenas de Pampa y Patagonia en los años previos a su sometimiento. Posteriormente, se describen los acontecimientos ligados a la "Conquista del Desierto", teniendo en cuenta al Estado argentino y a las diferentes "tribus". Luego, se caracteriza la situación de los indigenas después de 1885, y para finalizar, se analizan los relatos de los mapuche y ranqueles contemporaneos en el marco de su resurgimiento como pueblos preexistentes al Estado Nacional argentino.

Validating numerical simulations of snow avalanches using dendrochronology: the Cerro Ventana event in Northern Patagonia, Argentina

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A. Casteller

2008-05-01

Full Text Available The damage caused by snow avalanches to property and human lives is underestimated in many regions around the world, especially where this natural hazard remains poorly documented. One such region is the Argentinean Andes, where numerous settlements are threatened almost every winter by large snow avalanches. On 1 September 2002, the largest tragedy in the history of Argentinean mountaineering took place at Cerro Ventana, Northern Patagonia: nine persons were killed and seven others injured by a snow avalanche. In this paper, we combine both numerical modeling and dendrochronological investigations to reconstruct this event. Using information released by local governmental authorities and compiled in the field, the avalanche event was numerically simulated using the avalanche dynamics programs AVAL-1D and RAMMS. Avalanche characteristics, such as extent and date were determined using dendrochronological techniques. Model simulation results were compared with documentary and tree-ring evidences for the 2002 event. Our results show a good agreement between the simulated projection of the avalanche and its reconstructed extent using tree-ring records. Differences between the observed and the simulated avalanche, principally related to the snow height deposition in the run-out zone, are mostly attributed to the low resolution of the digital elevation model used to represent the valley topography. The main contributions of this study are (1 to provide the first calibration of numerical avalanche models for the Patagonian Andes and (2 to highlight the potential of Nothofagus pumilio tree-ring records to reconstruct past snow-avalanche events in time and space. Future research should focus on testing this combined approach in other forested regions of the Andes.

Argentina.

Science.gov (United States)

1986-06-01

This discussion of Argentina covers geography, the people, history and political conditions, government, economy, foreign relations, and relations between the US and Argentina. In 1985, the population of Argentina was estimated to be 30.6 million with an estimated annual growth rate of 1.5%. The infant mortality rate is 34.1/1000, and life expectancy is 70.2 years. Argentina, which shares land borders with Bolivia, Brazil, Chile, Paraguay, and Uruguay, is bounded by the Atlantic and the Antarctic Oceans. Descendants of Italian and Spanish immigrants predominate in Argentina, but many trace their origins to British and West and East European ancestors. In recent years, there has been a substantial influx of immigrants from neighboring Latin American countries. The native Indian population, estimated to be 50,000, is concentrated in the peripheral provinces of the north, northwest, and south. What is now Argentina was discovered in 1516 by the Spanish navigator Juan de Solia. The formal declaration of independence from Spain was made on July 9, 1816. In the late 19th century, 2 forces worked to create the modern Argentine nation: the introduction of modern agricultural techniques and the integration of Argentina into the world economy. Argentina has impressive human and natural resources, but political conflict and uneven economic performance since World War II have impeded full realization of its considerable potential. Yet, it is one of the wealthiest countries in Latin America. Among the reasons for the military coup of March 1976 was the deteriorating economy, caused by declining production and rampant inflation. Under the leadership of the Minister of the Economy, the military government focused attention on those immediate problems, and, in 1978, embarked on a new development strategy focusing on the establishment of a free market economy. There was little improvement in the economy, and a new economic plan was introduced in 1985 which has capped inflation by

OSTEOMETRÍA DE VICUGNA VICUGNA MOLINA, 1782 EN EL PLEISTOCENO FINAL DE PATAGONIA MERIDIONAL CHILENA: IMPLICANCIAS PALEOECOLÓGICAS Y BIOGEOGRÁFICAS / Osteometry of Vicugna vicugna Molina, 1782 in the late Pleistocene of southern chilean Patagonia

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Rafael Labarca Encina

2009-12-01

Full Text Available  Se presenta un análisis osteométrico uni y multivariado con los materiales fósiles -principalmente huesos cortos y falanges- de Vicugna sp. del yacimiento Cueva Lago Sofía 4 (13500 – 11000 AP, ubicado en la provincia de Última Esperanza (Región de Magallanes, Chile. Los resultados indican que los elementos analizados poseen un tamaño compatible con los registrados para Vicugna vicugna, no superando en ningún caso a los especímenes conocidos para Vicugna gracilis del Pleistoceno de la región Pampeana. Esto confirma la información morfológica y de ADN antiguo que indicaba la presencia de Vicugna vicugna en la Patagonia meridional chilena. Se discuten los resultados en términos taxonómicos, biogeográficos y paleoecológicos sugiriendo que la presencia de este taxón fuera de su rango actual de distribución se debió a las condiciones ambientales compartidas entre la Puna y Patagonia austral durante la transición Pleistoceno-Holoceno. La extinción de V. vicugna se habría debido al impacto de los cambios climáticos ocurridos al inicio del Holoceno producto de su dieta pastadora y etología no migratoria y territorial, a lo que se habría sumado una caza por parte de depredadores humanos y no humanos.Palabras clave: género Vicugna, osteometría, Pleistoceno, Patagonia AbstractThis contribution presents the results of single and multi-variable osteometric analyses performed on a sample of short bones and phalanxes assigned to Vicugna sp. from Lago Sofía Cave 4 site (13500 – 11000 BP, Región de Magallanes, Chile. The elements analyzed show a similar size to the reference collections for Vicugna vicugna, and do not exceed the metrics for the pampean pleistocenic specimens of Vicugna gracilis. This confirms the morphological and ancient DNA data that indicated the presence of vicuña in southern Chilean Patagonia. The taxonomic, biogeographic and palaeoecologic discussion of these results, suggests that the presence of this

Indirect searches of dark matter, and the galactic center at very high energy with H.E.S.S

International Nuclear Information System (INIS)

Viana, Aion

2012-01-01

H.E.S.S. (High Energy Stereoscopic System) is an array of four identical imaging atmospheric Cherenkov telescopes, designed to observe very high energy γ-rays (E > 100 GeV). The observation of such γ-rays plays a crucial role in the understanding of extreme non-thermal phenomena in the Universe. These γ-rays can be used for instance to search for annihilations of dark matter particles in dense environments of the Universe. This thesis presents a series of data analysis and phenomenological studies on two main subject of the γ-ray astronomy: the indirect searches of dark matter, and the study of the Galactic Center region. The indirect dark matter searches focus on the study of two classes of targets: dwarf galaxies and galaxy clusters. A detailed study of the H.E.S.S. observations towards the Sculptor and Carina dwarf galaxies, and towards the Fornax galaxy cluster are presented. In the absence, of a significant signal coming from these object, constraints on the annihilation cross section of dark matter particle candidates are derived. Particular consideration is given to different processes from particle physics and astrophysics which might give rise to additional contributions to the signal expected from a dark matter particle annihilation, such as the Sommerfeld effect and dark matter halo substructures. The current H.E.S.S. dark matter constraints towards the Sagittarius are updated in light of recent realistic dark matter halo models. A prospect on the sensitivity of the future generation of Cherenkov telescopes, i.e. CTA (Cherenkov Telescope Array), for the detection of a dark matter annihilation signal and conventional γ-ray emissions are also given. The second subject of this thesis provides a detailed analysis of the VHE γ-ray data from the Galactic Center region observed by H.E.S.S. This was possible thanks to the deep exposure of this region, achieved by the H.E.S.S. experiment throughout the 2004-2011 period. The analysis and spectral

Efecto del agregado de estiércol de gallina en el compostaje de aserrín y cascarilla de arroz

OpenAIRE

Leconte, María Corina

2010-01-01

Fil: Leconte, María Corina. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto Agrotécnico “Pedro M. Fuentes Godo”; Argentina. Fil; Satti, Patricia. Universidad Nacional del Comahue; Argentina. Fil: Mazzarino, María Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Fil: Mazzarino, María Julia. Universidad Naciona...

Aeolian sediment mass fluxes on a sandy soil in Central Patagonia

NARCIS (Netherlands)

Sterk, G.; Parigiani, J.; Cittadini, E.; Peters, P.; Scholberg, J.; Peri, P.

2012-01-01

The climate of Patagonia is semi-arid and characterised by frequent strong winds. Wind erosion is potentially a serious soil degradation process that impacts long-term sustainability of local agricultural systems, but the conditions and the rates of wind erosion in this region have not been

Geochronologic evidence of a large magmatic province in northern Patagonia encompassing the Permian-Triassic boundary

Science.gov (United States)

Luppo, Tomás; López de Luchi, Mónica G.; Rapalini, Augusto E.; Martínez Dopico, Carmen I.; Fanning, Christopher M.

2018-03-01

The Los Menucos Complex (northern Patagonia) consists of ∼6 km thick succession of acidic and intermediate volcanic and pyroclastic products, which has been traditionally assigned to the Middle/Late Triassic. New U/Pb (SHRIMP) zircon crystallization ages of 257 ± 2 Ma at the base, 252 ± 2 Ma at an intermediate level and 248 ± 2 Ma near the top of the sequence, indicate that this volcanic event took place in about 10 Ma around the Permian-Triassic boundary. This volcanism can now be considered as the effusive terms of the neighboring and coeval La Esperanza Plutono-Volcanic Complex. This indicates that the climax of activity of a large magmatic province in northern Patagonia was coetaneous with the end-Permian mass extinctions. Likely correlation of La Esperanza- Los Menucos magmatic province with similar volcanic and plutonic rocks across other areas of northern Patagonia suggest a much larger extension than previously envisaged for this event. Its age, large volume and explosive nature suggest that the previously ignored potential role that this volcanism might have played in climatic deterioration around the Permian-Triassic boundary should be investigated.

Detrital zircon geochronology and provenance of the Chubut Group in the northeast of Patagonia, Argentina

Science.gov (United States)

Navarro, Edgardo L.; Astini, Ricardo A.; Belousova, Elena; Guler, M. Verónica; Gehrels, George

2015-11-01

The Chubut Group constitutes the most widespread sedimentary unit in NE Patagonia, characterized by variable-energy fluvial deposits. U-Pb analysis of detrital zircons from two sections of the Chubut Group constraint the age of the oldest sedimentary rocks in the northeast of the Somuncurá - Cañadón Asfalto Basin. In the Cañadón Williams area, at San Jorge section, 20 km NW of Telsen locality, dating of 56 detrital zircons from a medium to coarse sandstone indicated a maximum depositional age of 109 ± 1 Ma (n = 4). These sandstones were interpreted to represent shallow channels, associated with a lacustrine system. In the Telsen locality, a laser ablation analysis of 115 detrital zircons from a medium to coarse-grained sandstone, from fluvial channel facies, yielded a maximum depositional age of ca. 106 ± 1 Ma (n = 8). Both ages are consistent with volcanic events of the Barremian to Albian age in the central Patagonian Andes Region. Cathodoluminescence images of zircons from the San Jorge sample suggest an igneous origin, which is further supported by Th/U values above 0.5 in most of the grains. The distribution of the statistical modes of the main age populations of detrital zircons for the two samples [182, 185 and 189 Ma for Telsen sample (T2S) and 181 ± 1 Ma for San Jorge sample (SJS)] matches the age of the volcanic Marifil Formation. The rocks of the Marifil Formation of these ages are exposed NE to SE of the study area. The abundance of zircons of similar Jurassic ages (n = 52 for SJS and n = 105 for T2S) and the external morphology of the zircons in the sample SJS, implies a close proximity of the source area. Suggestion that the Marifil Formation was the main provenance source is also supported by northeast-southeasterly paleocurrents measured at the San Jorge and Telsen sections.

Genomic insights into the origin and diversification of late maritime hunter-gatherers from the Chilean Patagonia.

Science.gov (United States)

de la Fuente, Constanza; Ávila-Arcos, María C; Galimany, Jacqueline; Carpenter, Meredith L; Homburger, Julian R; Blanco, Alejandro; Contreras, Paloma; Cruz Dávalos, Diana; Reyes, Omar; San Roman, Manuel; Moreno-Estrada, Andrés; Campos, Paula F; Eng, Celeste; Huntsman, Scott; Burchard, Esteban G; Malaspinas, Anna-Sapfo; Bustamante, Carlos D; Willerslev, Eske; Llop, Elena; Verdugo, Ricardo A; Moraga, Mauricio

2018-04-24

Patagonia was the last region of the Americas reached by humans who entered the continent from Siberia ∼15,000-20,000 y ago. Despite recent genomic approaches to reconstruct the continental evolutionary history, regional characterization of ancient and modern genomes remains understudied. Exploring the genomic diversity within Patagonia is not just a valuable strategy to gain a better understanding of the history and diversification of human populations in the southernmost tip of the Americas, but it would also improve the representation of Native American diversity in global databases of human variation. Here, we present genome data from four modern populations from Central Southern Chile and Patagonia ( n = 61) and four ancient maritime individuals from Patagonia (∼1,000 y old). Both the modern and ancient individuals studied in this work have a greater genetic affinity with other modern Native Americans than to any non-American population, showing within South America a clear structure between major geographical regions. Native Patagonian Kawéskar and Yámana showed the highest genetic affinity with the ancient individuals, indicating genetic continuity in the region during the past 1,000 y before present, together with an important agreement between the ethnic affiliation and historical distribution of both groups. Lastly, the ancient maritime individuals were genetically equidistant to a ∼200-y-old terrestrial hunter-gatherer from Tierra del Fuego, which supports a model with an initial separation of a common ancestral group to both maritime populations from a terrestrial population, with a later diversification of the maritime groups.

The inner 300 parsecs of the Milky Way seen by H.E.S.S.: a Pevatron in the Galactic Centre

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Moulin Emmanuel

2017-01-01

Full Text Available The Galactic Centre region has been observed by the High Energy Stereoscopic System (H.E.S.S. array of ground-based Cherenkov telescopes since 2004 leading to the detection of the very-high-energy γ-ray source HESS J1745-290 spatially coincident with the supermassive black hole Sagittarius A*. Diffuse TeV gamma-ray emission has been detected along the Galactic plane, most likely due to hadronic cosmic-ray interactions with the dense gas of the Central Molecular Zone. The rich 2004-2013 dataset permits detailed spectral and morphological studies of the diffuse emission in the inner 300 pc of the Galactic Centre region. The new results provide an important statement regarding the location and origin of the accelerator of PeV protons. The H.E.S.S. observations of the Pevatron are discussed in the context of the origin of Galactic cosmic rays.

HESS J1427−608: AN UNUSUAL HARD, UNBROKEN γ -RAY SPECTRUM IN A VERY WIDE ENERGY RANGE

Energy Technology Data Exchange (ETDEWEB)

Guo, Xiao-Lei; Gao, Wei-Hong [Department of Physics and Institute of Theoretical Physics, Nanjing Normal University, Nanjing 210046 (China); Xin, Yu-Liang; Liao, Neng-Hui; Yuan, Qiang; He, Hao-Ning; Fan, Yi-Zhong; Liu, Si-Ming, E-mail: yuanq@pmo.ac.cn, E-mail: gaoweihong@njnu.edu.cn, E-mail: liusm@pmo.ac.cn [Key Laboratory of Dark Matter and Space Astronomy, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

2017-01-20

We report the detection of a GeV γ -ray source that spatially overlaps and is thus very likely associated with the unidentified very high energy (VHE) γ -ray source HESS J1427−608 with the Pass 8 data recorded by the Fermi Large Area Telescope . The photon spectrum of this source is best described by a power law with an index of 1.85 ± 0.17 in the energy range of 3–500 GeV, and the measured flux connects smoothly with that of HESS J1427−608 at a few hundred gigaelectronvolts. This source shows no significant extension and time variation. The broadband GeV to TeV emission over four decades of energies can be well fitted by a single power-law function with an index of 2.0, without obvious indication of spectral cutoff toward high energies. Such a result implies that HESS J1427−608 may be a PeV particle accelerator. We discuss the possible nature of HESS J1427−608 according to the multiwavelength spectral fittings. Given the relatively large errors, either a leptonic or a hadronic model can explain the multiwavelength data from radio to VHE γ -rays. The inferred magnetic field strength is a few micro-Gauss, which is smaller than the typical values of supernova remnants (SNRs) and is consistent with some pulsar wind nebulae (PWNe). On the other hand, the flat γ -ray spectrum is slightly different from typical PWNe but is similar to that of some known SNRs.

Observations of the galactic center and search for exotic signals with H.E.S.S

International Nuclear Information System (INIS)

Vivier, M.

2009-06-01

Very high energy γ-ray astronomy is a new and young physics field which aims to study the origin of cosmic rays and their acceleration process inside various astrophysical objects such as pulsars, black holes or supernovae remnants. This is also a promising way to search for exotic high energy phenomena and unknown physics. This dissertation deals with three fundamental physics topics closely connected to very high energy γ-ray astronomy: particle acceleration in the vicinity of a supermassive black hole, primordial black holes evaporation, and indirect searches for (dark matter. Each of these topics is studied with data collected by the H.E.S.S (High Energy Stereoscopic System) instrument, an imaging Cherenkov array dedicated for the detection of very high energy γ-rays above 100 GeV. In the first part of the dissertation, we present a rapid overview of the field of very high energy γ-ray astronomy. A precise description of the H.E.S.S detector is then given as well as the data analysis techniques used to derive the results that are subsequently presented. The first subject is related to black hole astrophysics and concerns observations of the Galactic Center region with H.E.S.S. The source of the γ-ray emission discovered in 2004 toward this region is unidentified. A precise determination of the source energy spectrum and variability with new data is reported here. Results are then compared with models of particle acceleration in the vicinity of Sgr A * , the supermassive black hole located at the dynamical center of the Galaxy. In a second subject, the whole data collected with H.E.S.S is used to search for the signature o f primordial black holes evaporation through their emission of bursts of γ-rays. Primordial black holes are exotic objects that might have formed in the early stages of the Universe. As the bulk of the γ-ray emission is likely to originate from a standard astrophysical mechanism, the Galactic Center is not an ideal target for the

The History of Cosmic Ray Studies after Hess

Energy Technology Data Exchange (ETDEWEB)

Grupen, Claus, E-mail: grupen@physik.uni-siegen.de

2013-06-15

The discovery of cosmic rays by Victor Hess was confirmed with balloon flights at higher altitudes by Kolhörster. Soon the interest turned into questions about the nature of cosmic rays: gamma rays or particles? Subsequent investigations have established cosmic rays as the birthplace of elementary particle physics. The 1936 Nobel prize was shared between Victor Hess and Carl Anderson. Anderson discovered the positron in a cloud chamber. The positron was predicted by Dirac several years earlier. Many new results came now from studies with cloud chambers and nuclear emulsions. Anderson and Neddermeyer saw the muon, which for some time was considered to be a candidate for the Yukawa particle responsible for nuclear binding. Lattes, Powell, Occhialini and Muirhead clarified the situation by the discovery of the charged pions in cosmic rays. Rochester and Butler found V's, which turned out to be short-lived neutral kaons decaying into a pair of charged pions. Λ's, Σ's and Ξ's were found in cosmic rays using nuclear emulsions. After that period, accelerators and storage rings took over. The unexpected renaissance of cosmic rays started with the search for solar neutrinos and the observation of the supernova 1987A and other accelerators in the sky. With the observation of neutrino oscillations one began to look beyond the standard model of elementary particles. After 100 years of cosmic ray research we are again at the beginning of a new era, and cosmic rays may contribute to solve the many open questions, like dark matter and dark energy, by providing energies well beyond those of earth-bound accelerators.

Exploring the plutonic crust at a fast-spreading ridge:new drilling at Hess Deep

Energy Technology Data Exchange (ETDEWEB)

Gillis, Kathryn M. [Univ. of Victoria, BC (Canada). School of Earth and Ocean Sciences; Snow, Jonathan E. [Univ. of Houston, Houston, TX (United States). Earth & Atmospheric Sciences; Klaus, Adam [Texas A & M Univ., College Station, TX (United States). Integrated Ocean Drilling Program (IODP). United States Implementing Organization.; Guerin, Gilles [Lamont-Doherty Earth Observatory of Columbia Univ., Palisades, NY (United States). Borehole Research Group; Abe, Natsue [Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Yokosuka (Japan). Inst. for Research on Earth Evolution (IFREE); Akizawa, Norikatsu [Kanazawa Univ. (Japan). Dept. of Earth Sciences; Ceuleneer, Georges [Univ. Paul Sabatier, Toulouse (France). Observatoire Midi-Pyrenees (UMS 831), CNRS; Cheadle, Michael J. [Univ. of Wyoming, Laramie, WY (United States). Dept. of Geology and Geophysics; Adriao, Alden de Brito [Federal Univ. of Rio Grande do Sul, Porto Alegre (Brazil). Geology Inst. (IGEO); Faak, Kathrin [Ruhr Univ., Bochum (Germany). Geological Inst.; Falloon, Trevor J. [Univ. of Tasmania, Hobart, TAS (Australia). Inst. for Marine and Antarctic Studies; Friedman, Sarah A. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Geology; Godard, Marguerite M. [Univ. Montpellier II (France). Geosciences Montpellier-UMR 5243; Harigane, Yumiko [National Inst. of Advanced Industrial Science and Technology (AIST), Tsukuba (Japan). Marine Geology Dept.; Horst, Andrew J. [Syracuse Univ., NY (United States). Dept. of Earth Science; Hoshide, Takashi [Tohoku Univ., Sendai (Japan). Graduate School of Science; Ildefonse, Benoit [Univ. Montpellier II (France). Lab. de Tectonophysique; Jean, Marlon M. [Northern Illinois Univ., DeKalb, IL (United States). Dept. of Geology and Environmental Geosciences; John, Barbara E. [Univ. of Wyoming, Laramie, WY (United States). Dept. of Geology and Geophysics; Koepke, Juergen H. [Univ. of Hannover (Germany). Inst. of Mineralogy; Machi, Sumiaki [Kanazawa Univ. (Japan). Dept. of Earth Sciences; Maeda, Jinichiro [Hokkaido Univ., Sapporo (Japan). Dept. of Natural History Sciences; Marks, Naomi E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Chemistry and Material Sciences Dept.; McCaig, Andrew M. [Univ. of Leeds (United Kingdom). School of Earth and Environment; Meyer, Romain [Univ. of Bergen (Norway). Dept. of Earth Science and Centre for Geobiology; Morris, Antony [Univ. of Plymouth (United Kingdom). School of Earth, Ocean & Environmental Sciences; Nozaka, Toshio [Okayama Univ. (Japan). Dept. of Earth Sciences; Python, Marie [Hokkaido Univ., Sapporo (Japan). Dept. of Earth and Planetary Sciences; Saha, Abhishek [Indian Inst. of Science (IISC), Bangalore (India). Centre for Earth Sciences; Wintsch, Robert P. [Indiana Univ., Bloomington, IN (United States). Dept. of Geological Sciences

2013-02-28

Integrated Ocean Drilling Program (IODP) Hess Deep Expedition 345 was designed to sample lower crustal primitive gabbroic rocks that formed at the fast-spreading East Pacific Rise (EPR) in order to test models of magmatic accretion and the intensity of hydrothermal cooling at depth. The Hess Deep Rift was selected to exploit tectonic exposures of young EPR plutonic crust, building upon results from ODP Leg 147 as well as more recent submersible, remotely operated vehicle, and near-bottom surveys. The primary goal was to acquire the observations required to test end-member crustal accretion models that were in large part based on relationships from ophiolites, in combination with mid-ocean ridge geophysical studies. This goal was achieved with the recovery of primitive layered olivine gabbros and troctolites with many unexpected mineralogical and textural relationships, such as the abundance of orthopyroxene and the preservation of delicate skeletal olivine textures.

La proyección colonial de Chile a la Patagonia Insular en el siglo XVIII

Directory of Open Access Journals (Sweden)

Urbina Carrasco, María Ximena

2011-12-01

Full Text Available In this article, the geopolitical consequences of the shipwreck of the English frigate Wager and the landfall of the ship Anna into the coasts of the Western Insular Patagonia in 1741 are presented, which were part of the fleet of George Anson. The news reporting the English presence in the deserted and unknown insular and coastal territory southernmost Chiloé, and which had disseminated towards the end of the continent, promoted the deployment of different actions tending to make presence noted, such as military and missionary expeditions, fort establishment and area patrols. None of the latter implied a permanent settlement or effective incorporation of such border, although they indeed involved the creation of a «mobile frontier» for Chiloé and the development of a Western Patagonia image.

Este artículo presenta las consecuencias geopolíticas del naufragio de la fragata inglesa Wager y la recalada de otro barco, el Anna, que formaban parte de la flota de George Anson, en las costas de la Patagonia Occidental Insular en 1741. La noticia de la presencia inglesa en el despoblado y desconocido territorio insular y bordemarino al sur de Chiloé, y que se proyectaba al fin del continente, generó el despliegue de acciones tendentes a marcar presencia, como expediciones militares y misionales, la fundación de un fuerte y el patrullaje por la zona. Nada de esto se tradujo en un asentamiento permanente o incorporación efectiva de dicha frontera, pero si en la conformación de una «frontera móvil» de Chiloé, y la construcción de una imagen de la Patagonia Occidental.

Modulation of Fire Regimes by Vegetation and Site Type in Southwestern Patagonia Since 13 ka

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Patricio I. Moreno

2018-04-01

Full Text Available The degree to which vegetation and site type have influenced fire regimes through the Holocene has not been investigated in detail in the temperate ecosystems of southern Patagonia. Here we present a first attempt using a paired-basin approach to study the evolution of fire regimes in sectors dominated by humid Nothofagus forests and the xeric Patagonian steppe in the Magallanes region of Chilean Patagonia (51°S. We analyzed sediment cores from two small lakes and a bog located within the same climate zone on opposite sides of the forest-steppe ecotone, ~28 km apart. The position of this biological boundary east of the Andes is controlled by the strength and position of the southern westerly winds, which constitute the sole source of precipitation throughout western Patagonia. Our results indicate that fires have occurred in the study region repeated times over the last ~13,000 years at bi- and tridecadal timescales. Sectors currently dominated by Patagonian steppe feature high frequency and low magnitude of local fires, and vice versa in humid forests. Climate-driven expansion of Nothofagus scrubland/woodland into steppe environments over the last ~4,200 years increased the magnitude and lowered the frequency of fire events, culminating with peak Nothofagus abundance, fire magnitude and frequency during the last millennium. We also detect divergences between lake-based vs. bog-based paleofire histories among paired sites located within the Patagonian steppe, ~12 km apart, which we attribute to local burning of the bog at times of lowered water table. This divergence suggests to us that bog-based vegetation and fire histories exacerbate a local, azonal, signal blurring extra-local or regional regimes, thus accounting for some discrepancies in the Quaternary paleovegetation/paleoclimate literature of southern Patagonia.

Modeling the emission of the galactic very high energy γ-ray sources G 1.9+0.3, G 330.2+1.0, HESS J1303-631 and PSR B1259-63/LS 2883 observed with H.E.S.S

International Nuclear Information System (INIS)

Sushch, Iurii

2012-01-01

Recently, imaging atmospheric Cherenkov telescopes (IACTs) have discovered numerous new sources representing various source classes in the very high energy (VHE; E>100 GeV) sky. This work presents studies of representatives of three types of Galactic VHE emitters: the Supernova remnants (SNRs) G1.9+0.3 and G330.2+1.0, the pulsar wind nebula (PWN) HESS J1303.631 and the binary system PSR B1259.63/LS 2883. The analysis of the H.E.S.S. data and the broadband emission modeling are presented. G1.9+0.3 and G330.2+1.0 are synchrotron-dominated SNRs whose non-thermal X-ray emission implies that intensive particle acceleration occurs at their shock fronts. This makes them promising candidates for the detection at VHEs. They were observed by the High Energy Stereoscopic System (H.E.S.S.) yielding no signs of significant VHE γ-ray emission from either SNR. The 99% confidence level upper limits on the TeV flux were determined. For an assumed spectral index of 2.5 the obtained upper limits are F G1.9 (>260 GeV) -13 cm -2 s -1 for G1.9+0.3 and F G330 (>380 GeV) -12 cm -2 s -1 for G330.2+1.0. Upper limits on the VHE emission provide constraints on the interior magnetic field in the context of a leptonic scenario and on the interstellar medium (ISM) density and cosmic-ray (CR) efficiency in a hadronic scenario. Lower limits on the interior magnetic fields were estimated at 15 μG for G1.9+0.3 and 14 μG for G330.2+1.0. In the case of the hadronic scenario, the H.E.S.S. upper limits are two orders of magnitude greater than the flux prediction. Obtained upper limits on the ISM densities are compatible with other estimates of the densities (from the thermal X-ray emission for G330.2+1.0 and from the expansion rate for G1.9+0.3). The CR efficiency cannot be constrained with the current H.E.S.S. upper limits. HESS J1303-631 is an initially unidentified H.E.S.S. source which was recently identified as a PWN associated with the pulsar PSR J1301-6305. The broadband emission of the source

Marcas urbanas y sentidos sociales en disputa. San Carlos de Bariloche, Argentina, 1966-1983

Directory of Open Access Journals (Sweden)

Paula Gabriela Núñez

2013-07-01

Full Text Available San Carlos de Bariloche es la principal localidad turística de la Patagonia argentina. Representa, por su dimensión, a la ciudad más poblada de la provincia de Río Negro y es la tercera en tamaño en la Patagonia. Su crecimiento demográfico ha estado nutrido por diferentes migraciones nacionales y extranjeras. De estas últimas las principales provienen de países latinoamericanos. El artículo apunta a indagar en  la desvalorización de su migración más importante, la chilena, durante la segunda mitad del siglo XX. Esta exclusión se fortaleció entre 1966 y 1983, por las iniciativas estatales que exacerbaron la xenofobia, las persecuciones políticas, la precarización de las condiciones laborales y los cambios en la organización espacial durante los gobiernos dictatoriales del período, esto es, los que se desarrollaron de 1966 a 1973 y de 1976 a 1983. El presente artículo analiza cómo algunos espacios de Bariloche se constituyeron en marcas urbanas que representaron intereses de los sectores más visibles en nombre de la “nación”, al tiempo que revisa dispositivos de resistencia de sectores excluidos de migrantes chilenos, que tuvieron, paralelamente, componentes de construcción espacial. Para este último punto se aborda la construcción de la Capilla Nuestra Señora del Carmen en 1966, construida en el área conocida como “barrio de los chilenos”, que se levantó como una marca alternativa, tanto material como simbólica, para disputar pertenencia, reconocimiento y visibilidad.

The Usefulness of Edible and Medicinal Fabaceae in Argentine and Chilean Patagonia: Environmental Availability and Other Sources of Supply

OpenAIRE

Molares, Soledad; Ladio, Ana

2011-01-01

Fabaceae is of great ethnobotanical importance in indigenous and urban communities throughout the world. This work presents a revision of the use of Fabaceae as a food and/or medicinal resource in Argentine-Chilean Patagonia. It is based on a bibliographical analysis of 27 ethnobotanical sources and catalogues of regional flora. Approximately 234 wild species grow in Patagonia, mainly (60%) in arid environments, whilst the remainder belong to Sub-Antarctic forest. It was found that 12.8% (30 ...

Mammalia, Rodentia, Sigmodontinae, Holochilus brasiliensis (Desmarest, 1819: Distribution extention

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Formoso, A. E.

2010-01-01

Full Text Available We report the southernmost record for the marsh rats Holochilus brasiliensis 20 km S of Pedro Luro on Hwy3, province of Buenos Aires, Argentina (39°41’31.13”S, 62°40’23.5”W extending the range of the species ca. 110 km S.This represents the first contemporaneous record of H. brasiliensis in Patagonia, and also the only species of sigmodontinerodent with amphibious habits reported in Patagonia.

Analysis of admixture and genetic structure of two Native American groups of Southern Argentinean Patagonia.

Science.gov (United States)

Sala, Andrea; Corach, Daniel

2014-03-01

Argentinean Patagonia is inhabited by people that live principally in urban areas and by small isolated groups of individuals that belong to indigenous aboriginal groups; this territory exhibits the lowest population density of the country. Mapuche and Tehuelche (Mapudungun linguistic branch), are the only extant Native American groups that inhabit the Argentinean Patagonian provinces of Río Negro and Chubut. Fifteen autosomal STRs, 17 Y-STRs, mtDNA full length control region sequence and two sets of Y and mtDNA-coding region SNPs were analyzed in a set of 434 unrelated individuals. The sample set included two aboriginal groups, a group of individuals whose family name included Native American linguistic root and urban samples from Chubut, Río Negro and Buenos Aires provinces of Argentina. Specific Y Amerindian haplogroup Q1 was found in 87.5% in Mapuche and 58.82% in Tehuelche, while the Amerindian mtDNA haplogroups were present in all the aboriginal sample contributors investigated. Admixture analysis performed by means of autosomal and Y-STRs showed the highest degree of admixture in individuals carrying Mapuche surnames, followed by urban populations, and finally by isolated Native American populations as less degree of admixture. The study provided novel genetic information about the Mapuche and Tehuelche people and allowed us to establish a genetic correlation among individuals with Mapudungun surnames that demonstrates not only a linguistic but also a genetic relationship to the isolated aboriginal communities, representing a suitable proxy indicator for assessing genealogical background.

Uncinaria hamiltoni (Nematoda: Ancylostomatidae) in South American sea lions, Otaria flavescens, from northern Patagonia, Argentina.

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Berón-Vera, B; Crespo, E A; Raga, J A; Pedraza, S N

2004-08-01

Thirty-one South American sea lion pups (Otaria flavescens) found dead in Punta León, Argentina, during the summer of 2002, were examined for hookworms (Uncinaria hamiltoni). Parasite parameters were analyzed in 2 locations of the rookery, i.e., a traditional, well-structured breeding area and an expanding area with juveniles and a lax social structure. Prevalence of hookworms was 50% in both localities, and no difference was observed in prevalence between pup sexes (P > 0.05). Hookworms were concentrated in the small intestine. Transmammary transmission is assumed because only adult hookworms were found in the pups. The mean intensity of hookworms per pup was 135; the mean intensity in females (92.78) was significantly different (P 0.05) in intensity was found between the 2 breeding areas, although prevalence was higher in the traditional breeding area than in the other area. Location was the only factor affecting hookworm prevalence (P log-linear model: 0.9552; chi2: 1.5629). No apparent trend between body condition and intensity of hookworms was observed.

About dark matter search and diffuse gamma ray emission with the H.E.S.S. experiment

International Nuclear Information System (INIS)

Charbonnier, A.

2010-01-01

Very high energy gamma-ray astronomy (E ≥ 30 GeV), that allows to probe non-thermal processes in the universe, is a rather young field of research. Up to now, most of the objects that have been observed are point-like or have small spatial extensions. However, the interaction of cosmic rays with the interstellar medium is expected to give rise to a diffuse emission at these energies. A preliminary study of the detectability of this diffuse component by the H.E.S.S. telescope array is presented. The latter has been operating since 2004 and detects the Cherenkov light from atmospheric showers that are generated by very high energy photons. The standard On-O background subtraction method is investigated along with the influence of the sky background noise on the recorded event rate. A second theme covered by this thesis is that of the detectability of dark matter by the H.E.S.S. experiment. This is performed using Clumpy, a semi-analytical code developed during this thesis. The Clumpy code calculates the gamma-ray flux from dark matter annihilation from user-defined galactic structure and sub-structure distributions. The H.E.S.S. ∼15 hour long observation of the Carina dwarf spheroidal galaxy has furthermore set an upper limit at 10 -22 cm 3 s -1 for the dark matter annihilation cross section. (author)

Range expansion of Oligoryzomys longicaudatus (Rodentia, Sigmodontinae in Patagonian Chile, and first record of Hantavirus in the region Ampliación del rango de distribución de Oligoryzomys longicaudatus (Rodentia, Sigmodontinae en la Patagonia de Chile y primer registro de Hantavirus en la región

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SEBASTIÁN BELMAR-LUCERO

2009-06-01

Full Text Available At present, 20 species of Oligoryzomys (Rodentia, Sigmodontinae are recognized in the Neotropical region, most of them distinguished by their karyotypes, which fluctuates between 46-70 chromosomes. Two species are currently recognized in Chile, Oligoryzomys longicaudatus (Bennet, 1832; "colilargo" or the long-tailed pygmy rice rat; 2n = 56, which ranges from 27° to approximately 51° S, and O. magellanicus (Bennet, 1836; Magellanic pygmy rice rat; 2n = 54, south of 51° S in the Patagonian region of Chile and Argentina. As part of an ongoing research on the southern Patagonia of Chile, we report the results of small mammal samplings in six localities. We karyotyped 28 specimens and we also sequenced the hypervariable mtDNA region I in 22 individuals, aligning these sequences with an under development phylogeny of O. longicaudatus. We also evaluated the serology and viral charge in all captured specimens to detect the presence of antibodies to Andes virus (ANDV through Strip Immunoblot Assay (SIA, and of viral genome by RT-PCR. The results consistently showed that the karyotype of southern Patagonia specimens was 2n = 56, equal to that of O. longicaudatus, and that individuals from this area do not differentiate phylogenetically from those of the northern range of distribution. In addition, the serology showed the presence of antibodies IgG anti-ANDV and of viral genome in heart, kidney, spleen, and lungs of a single specimen of Oligoryzomys from the locality of Fuerte Bulnes in the Magallanes region. We conclude that all specimens trapped south of 51° S correspond to Oligoryzomys longicaudatus, thus expanding the distribution of this specie! from 51° to at least 55° S. The results also extended the disiribution of the Andes strain of Hantavirus to southernmost Patagonia.Actualmente se reconocen 20 especies de Oligoryzomys (Rodentia, Sigmodontinae en la región Neotropical, la mayoría de ellas distinguidas por sus cariotipos, los que fluct

Eastern Andean environmental and climate synthesis for the last 2000 years BP from terrestrial pollen and charcoal records of Patagonia

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Sottile, G. D.; Echeverria, M. E.; Mancini, M. V.; Bianchi, M. M.; Marcos, M. A.; Bamonte, F. P.

2015-06-01

The Southern Hemisphere Westerly Winds (SWW) constitute an important zonal circulation system that dominates the dynamics of Southern Hemisphere mid-latitude climate. Little is known about climatic changes in the Southern South America in comparison to the Northern Hemisphere due to the low density of proxy records, and adequate chronology and sampling resolution to address environmental changes of the last 2000 years. Since 2009, new pollen and charcoal records from bog and lakes in northern and southern Patagonia at the east side of the Andes have been published with an adequate calibration of pollen assemblages related to modern vegetation and ecological behaviour. In this work we improve the chronological control of some eastern Andean previously published sequences and integrate pollen and charcoal dataset available east of the Andes to interpret possible environmental and SWW variability at centennial time scales. Through the analysis of modern and past hydric balance dynamics we compare these scenarios with other western Andean SWW sensitive proxy records for the last 2000 years. Due to the distinct precipitation regimes that exist between Northern (40-45° S) and Southern Patagonia (48-52° S) pollen sites locations, shifts on latitudinal and strength of the SWW results in large changes on hydric availability on forest and steppe communities. Therefore, we can interpret fossil pollen dataset as changes on paleohydric balance at every single site by the construction of paleohydric indices and comparison to charcoal records during the last 2000 cal yrs BP. Our composite pollen-based Northern and Southern Patagonia indices can be interpreted as changes in latitudinal variation and intensity of the SWW respectively. Dataset integration suggest poleward SWW between 2000 and 750 cal yrs BP and northward-weaker SWW during the Little Ice Age (750-200 cal yrs BP). These SWW variations are synchronous to Patagonian fire activity major shifts. We found an in phase

Le site paléo-indien de Piedra Museo (Patagonie). Sa contribution au débat sur le premier peuplement du continent américainThe palaeo-indian site of Piedra Museo (Patagonia). Its contribution to the debate on the peopling of the Americas.

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Ramirez Rozzi, Fernando V.; d'Errico, Francesco; Zarate, Marcelo

2000-08-01

The Piedra Museo site (Santa Cruz, Argentina), excavated over the past nine years has yielded a rich archaeological record, which contributes to the discussion on the first peopling of the Americas. We present here a new study of the site, based on an analysis of the stratigraphy, spatial distribution of archaeological remains, bone taphonomy, and discussion of new AMS- 14C dates. We conclude that remains of extinct species with cut-marks from the lower levels are contemporaneous of stone tools and cores from the same levels. This demonstrates that humans were present in the southern part of Patagonia around 10 300 and 11 100 years BP and suggests that hunting of large mammals was a part of their subsistence strategies.

Levaduras fermentadoras aisladas de Cyttaria hariotii (Fungi en bosques Andino-Patagónicos (Argentina Fermenting yeasts isolated from Cyttaria hariotii (Fungi in the Andean Patagonic Forest

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José Ulloa

2009-12-01

Full Text Available Las levaduras han estado asociadas al hombre desde épocas muy tempranas. Entre estas se destacan las fermentadoras debido a su importancia en la industria de los alimentos. Las implicancias biotecnológicas de estas levaduras han sido extensamente estudiadas, sin embargo la distribución en la naturaleza y la ecología de estas no se encuentra igualmente documentada. El presente estudio se realizó en el Parque Nacional Nahuel Huapi (Noroeste Patagónico, Argentina sobre Cyttaria hariotii, hongo ascomicético parásito de árboles del género Nothofagus. Mediante el uso de un medio selectivo con etanol 8 % se obtuvieron 72 aislamientos. Los mismos fueron ordenados en cinco grupos en base a pruebas morfológicas y fisiológicas, tres de los cuales fueron asignados a los géneros Saccharomyces, Pichia y Kloeckera. El grupo Saccharomyces presentó el mayor número de aislamientos y se subdividió en tres subgrupos, dos de ellos presentan alta afinidad con S. bayanus y/ó S. uvarum. La totalidad de los aislamientos fueron psicrotolerantes y la temperatura máxima de crecimiento osciló entre 35 y 37 _C. El presente trabajo contribuye al conocimiento de la biodiversidad de levaduras de la Patagonia y representa el primer aislamiento masivo de levaduras sacaromicéticas en ambientes naturales de la región.Yeasts have been associated with mankind from early ages. Among these, fermentative yeasts played the most relevant role, due to its importance in the food industry. The biotechnological implications of these yeasts have been extensively studied. However there is a lack of information about its distribution in nature and ecology. In this study samples of Cyttaria hariotii, ascomycete fungus parasite of trees of the genus Nothofagus, were collected in Nahuel Huapi National Park (Northwestern Patagonia, Argentina. 72 isolates were obtained using a selective culture medium with 8% ethanol. Identification of the isolates was based on morphological and

Modeling the emission of the galactic very high energy {gamma}-ray sources G 1.9+0.3, G 330.2+1.0, HESS J1303-631 and PSR B1259-63/LS 2883 observed with H.E.S.S

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Sushch, Iurii

2012-10-19

Recently, imaging atmospheric Cherenkov telescopes (IACTs) have discovered numerous new sources representing various source classes in the very high energy (VHE; E>100 GeV) sky. This work presents studies of representatives of three types of Galactic VHE emitters: the Supernova remnants (SNRs) G1.9+0.3 and G330.2+1.0, the pulsar wind nebula (PWN) HESS J1303.631 and the binary system PSR B1259.63/LS 2883. The analysis of the H.E.S.S. data and the broadband emission modeling are presented. G1.9+0.3 and G330.2+1.0 are synchrotron-dominated SNRs whose non-thermal X-ray emission implies that intensive particle acceleration occurs at their shock fronts. This makes them promising candidates for the detection at VHEs. They were observed by the High Energy Stereoscopic System (H.E.S.S.) yielding no signs of significant VHE {gamma}-ray emission from either SNR. The 99% confidence level upper limits on the TeV flux were determined. For an assumed spectral index of 2.5 the obtained upper limits are F{sub G1.9}(>260 GeV)<4.6 x 10{sup -13} cm{sup -2}s{sup -1} for G1.9+0.3 and F{sub G330}(>380 GeV)<1.6 x 10{sup -12} cm{sup -2}s{sup -1} for G330.2+1.0. Upper limits on the VHE emission provide constraints on the interior magnetic field in the context of a leptonic scenario and on the interstellar medium (ISM) density and cosmic-ray (CR) efficiency in a hadronic scenario. Lower limits on the interior magnetic fields were estimated at 15 {mu}G for G1.9+0.3 and 14 {mu}G for G330.2+1.0. In the case of the hadronic scenario, the H.E.S.S. upper limits are two orders of magnitude greater than the flux prediction. Obtained upper limits on the ISM densities are compatible with other estimates of the densities (from the thermal X-ray emission for G330.2+1.0 and from the expansion rate for G1.9+0.3). The CR efficiency cannot be constrained with the current H.E.S.S. upper limits. HESS J1303-631 is an initially unidentified H.E.S.S. source which was recently identified as a PWN associated with

ON THE UNDERSTANDING OF AEOLIAN SEQUENCE STRATIGRAPHY: AN EXAMPLE FROM MIOCENE-PLIOCENE DEPOSITS IN PATAGONIA, ARGENTINA

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CARLOS ZAVALA

2001-07-01

Full Text Available Upper Tertiary aeolian strata (Río Negro Formation outcrop in extensive sea cliffs at the Northeast of Patagonia. These outcrops show deposits corresponding to a complete suite of aeolian and aeolian related sub-environments, and also provide excellent exposures to analyse the sedimentology and internal architecture from a sequence stratigraphic point of view. Field studies, supplemented withline-drawings of oblique photographs, allowed the recognition of seven aeolian depositional sequences within the succession, each one bounded by regional super surfaces (or deflation surfaces. Internally these aeolian sequences display a cyclic recurrence in facies, that yields a tentative genetic model for their evolution. As documented from field examples, each basic aeolian depositional sequence was deposited during a single aggradational period, and is bounded by unconformities related to degradational periods. Degradational periods are regional deflationary events, that resulted in deep-scoured to flat surfaces, characterised by erosion / non deposition in which the only recognised accumulation is isolated and large angular blocks of fine-grained aggregates, interpreted as residual remnants of deposits of the previous sequence. Aggradational periods are characterised by a near- continuous accumulations responsible for the sequence building. Differences in the aeolian sediment budget to the area and the rising rate of water table control the related facies types, and allow to discriminateearly and late aggradational sub-periods. Early aggradational sub-periods form under conditions of relatively fast rising water tables associated with moderate aeolian sediment budget, thus resulting in the development of extended wet interduneslaterally associated with aeolian dunes and dry interdunes. During late aggradational sub-periods, the depositional surface outdistanced the water table, and aeolian dunes and dry interdunes tend to predominate. This sub

Precious metal-bearing epithermal deposits in western Patagonia (NE Lago Fontana region), Argentina

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Lanfranchini, Mabel Elena; Etcheverry, Ricardo Oscar; de Barrio, Raúl Ernesto; Recio Hernández, Clemente

2013-04-01

Precious metal-bearing quartz veins occur at the northeastern sector of the Lago Fontana region in southwestern Argentina, within the context of the Andean continental magmatic arc environment. The deposits and their associated alteration zones are spatially related to a Cretaceous calc-alkaline magmatism represented by silicic dikes and hypabyssal intrusions, and hosted by a Late Jurassic to Cretaceous volcano-sedimentary sequence. The veins and related veinlets crop out discontinuously, in general terms in a NW-SE belt. The primary vein mineral assemblage is composed mostly of pyrite ± galena ± chalcopyrite > hematite ± arsenopyrite in silica gangue minerals. Chemical analyses of grab samples from selected quartz veins show as much as 5.7 ppm Au and 224 ppm Ag, as well as elevated Pb, Cu, and Zn. Hydrothermal fluids caused an innermost silicification and adularia-sericite alteration assemblage, and an external propylitic halo. Sulfur isotope values measured for sulfides (δSS from -1.90 to +1.56‰), and oxygen and hydrogen isotopes measured on quartz crystals and extracted primary fluid inclusion waters (δOO = -2.85 to +5.40‰; δDO = -106.0 to -103.4‰) indicate that mineralization probably formed from magmatic fluids, which were mixed with meteoric waters. Also, fluid inclusion data from quartz veins point out that these fluids had low salinity (1.7-4.2 wt% NaCl equiv.), and temperatures of homogenization between 180 and 325 °C. Mineralogical, petrographic and geochemical features for mineralized surface exposures indicate a typical adularia-sericite, low sulfidation epithermal system in the Lago Fontana area that represents a promising target for further exploration programs.

Occurrence and levels of glyphosate and AMPA in shallow lakes from the Pampean and Patagonian regions of Argentina.

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Castro Berman, M; Marino, D J G; Quiroga, María Victoria; Zagarese, Horacio

2018-06-01

Glyphosate (N-(phosphonomethyl)glycine) is a broad-spectrum systemic herbicide used to kill weeds that compete with commercial crops. In Argentina, the use of glyphosate-based herbicides increased dramatically (up to ∼200,000 tons on 2012) since the introduction of glyphosate-resistant crops, such as transgenic soy and resistant corn, and the adoption of non-till practices in the 1990's. Sallow lakes within the Pampa region may be potentially impacted by continuous herbicide usage. We surveyed 52 shallow lakes from the Pampa region (Buenos Aires Province, Argentina) to assess the occurrence and concentrations of glyphosate and its main degradation product (AMPA). For comparison, we also sampled 24 shallow lakes from an area with no agricultural use of glyphosate (Northern Patagonia). Glyphosate and AMPA were analyzed by UPLC-MS/MS ESI (±) in lake water, suspended particulate matter (SPM), and sediment samples. Within the Pampa region, glyphosate residues were detected in >40% of samples. Glyphosate residues were detected more frequently in sediment and surface water than in SPM samples. The mean (maximum) concentrations of glyphosate were 2.11 (4.52) μg l -1 for surface water; 0.10 (0.13) μg l -1 for SPM and 10.47 (20.34) μg kg -1 for sediment samples, respectively. Whereas, mean (maximum) concentrations of AMPA were 0.84 and (0.90) μg l -1 for surface water; 0.07 (0.07) μg l -1 for SPM; and 22.53 (32.89) μg kg -1 for sediment samples. The herbicide was not detected in samples from the Patagonian region. To our knowledge, this is the first study reporting the occurrence and concentrations of the herbicide in freshwater lakes of Argentina. Copyright © 2018 Elsevier Ltd. All rights reserved.

Differential use of the Argentine shelf by wintering adults and juveniles southern giant petrels, Macronectes giganteus, from Patagonia

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Blanco, Gabriela S.; Quintana, Flavio

2014-08-01

To study habitat use and at-sea movements of southern giant petrels (SGP) during non-breeding period, we deployed 15 satellite transmitters (six adults, nine juveniles) at Isla Arce and Isla Gran Robredo colonies in Patagonia, Argentina. Birds were instrumented during 81.4 ± 37 days. Adult birds used 74% of the Argentine shelf concentrating mainly at the shelf break, middle shelf waters, and the surroundings of the colony. After fledging, juveniles spread to the Argentine, Uruguayan and Brazilian shelves within the South Atlantic. Adults alternated at-sea excursions (12 ± 5 days) with periods at the colony of 3 ± 0.3 days. Contrarily, juveniles moved first to the shelf break and then traveled northwards reaching the south of Brazil. There was some spatial overlap between age classes, but only during the first 30 days after juveniles had fledged; thereafter there was not overlap between the areas used by both age classes. The Argentine shelf is widely used by different species offering a suitable environment for foraging; this may be why adults SGP from Patagonian colonies spend all year-round within the Argentine shelf. The identification of used areas of non-breeding SGP fills a gap in the species knowledge contributing not only to the preservation the species, but also to the management of marine areas globally recognized as important for many other Procellariiformes.

Ash resuspension related to the 2011-2012 Cordón Caulle eruption, Chile, in a rural community of Patagonia, Argentina

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Forte, Pablo; Domínguez, Lucia; Bonadonna, Costanza; Gregg, Chris E.; Bran, Donaldo; Bird, Deanne; Castro, Jonathan M.

2018-01-01

The 2011-2012 Cordón Caulle eruption emitted about 1 km3 of rhyodacitic tephra. Dominant westerly winds in the region caused most of the primary tephra to deposit in neighboring Argentina. In addition to the impact of widespread dispersal and fallout of primary tephra during the eruption, Argentina was also significantly affected by remobilization of the primary ash even several years after the climactic phase of the eruption. In this mixed methods study, we combine aspects of natural and social sciences to characterize the ash resuspension events associated with the 2011-2012 Cordón Caulle deposits and assess the impacts on the Argentinian farming community of Ingeniero Jacobacci in the Patagonian Steppe. Our findings show the primary importance of wind, rainfall and ash availability in controlling the occurrence and persistence of ash resuspension events. The role played by these variables was also reflected in the seasonal distribution of events observed. Regarding the impacts, our results complement those of earlier studies and demonstrate that ash resuspension events can exacerbate the negative impact of primary tephra fallout events from the time of deposition to many years after the eruption. Only after five years has the environment and the farming community begun to show signs of recovery. Our findings also highlight the importance of assessing ash resuspension events in multi-hazard scenarios involving volcanic and hydrometeorologic hazards.

Detection of VHE gamma-ray emission from the vicinity of PSR B1706-44 with H.E.S.S.

Energy Technology Data Exchange (ETDEWEB)

Chaves, Ryan C.G.; Ona Wilhelmi, Emma de [Max-Planck-Institut fuer Kernphysik, Heidelberg (Germany); Terrier, Regis [APC, CNRS, Univ. Paris-7 (France); Stegmann, Christian [Universitaet Erlangen-Nuernberg, Erlangen (Germany). Physikalisches Institut; Khelifi, Bruno [LLR, Ecole Polytechnique, CNRS/IN2P3, Palaiseau (France); Jager, Okkie C. de [Unit for Space Physics, North-West Univ., Potchefstroom (South Africa)

2010-07-01

The gamma-ray pulsar PSR B1706-44 and the adjacent supernova remnant (SNR) candidate G343.1-2.3 were observed by H.E.S.S. during a dedicated observational campaign in 2007. A new source of very-high-energy (VHE;E>100 GeV) gamma-ray emission, HESS J1708-443, was discovered with its centroid at RA(J2000.0)=17 h 8 m 10 s and Dec (J2000.0)=-44 d 21{sup '} ({+-}3{sup '} statistical error on each axis). The VHE gamma-ray source is significantly more extended than the H.E.S.S. point-spread function and has an intrinsic Gaussian width of 0.29 {+-}0.04 . Its energy spectrum can be described by a power law with a photon index=2.0{+-}0.1 (stat){+-}0.2 (syst). The integral flux measured between 1 and 10 TeV is {proportional_to}17% of the Crab Nebula flux in the same energy range. The possible associations with the energetic PSR B1706-44, also recently detected in the GeV domain with Fermi/LAT and AGILE, and SNR G343.1-2.3 are discussed.

Fermi-LAT Constraints on the Pulsar Wind Nebula Nature of HESS J1857+026

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Rousseau, R.; Grondin, M.-H.; VanEtten, A.; Lemoine-Goumard, M.; Bogdanov, S.; Hessels, J. W. T.; Kaspi, V. M.; Arzoumanian, Z.; Camilo, F.; Casandjian, J. M.;

PLANTAS AROMÁTICAS CON ÓRGANOS SUBTERRÁNEOS DE IMPORTANCIA CULTURAL EN LA PATAGONIA ARGENTINA: UNA APROXIMACIÓN A SUS USOS DESDE LA ETNOBOTÁNICA, LA PERCEPCIÓN SENSORIAL Y LA ANATOMÍA

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Soledad Molares

2012-01-01

Full Text Available Se analiza la etnobotánica y anatomía de cinco especies aromáticas de uso medicinal y/o comestible altamente valoradas en la Patagonia argentina: Valeriana clarionifolia, V. carnosa (Valerianaceae, Azorella monantha, Osmorhiza chilensis y Eryngium paniculatum (Apiaceae. El principal énfasis ha sido la caracterización de las estructuras secretoras de sus órganos subterráneos y su posible vinculación con las percepciones sensoriales y usos dados por los pobladores. El trabajo etnobotánico se realizó en dos comunidades indígenas Mapuches de la Provincia de Neuquén y en otras dos de la Provincia de Chubut, con un total de 53 entrevistas. El trabajo anatómico consistió en la observación estructural y ultraestructural de las estructuras secretoras. Los informantes indicaron que E. paniculatum es principalmente usada para tratar trastornos digestivos y hepáticos, O. chilensis para problemas de la visión y A. monantha como urinaria y antitusiva; además los órganos subterráneos de estas tres especiesse consumen crudos y/o cocidos. Las especies de Valeriana son usadas principalmente como analgésicas, digestivas, antitusivas y en síndromes culturales. El sabor y el aroma son las principales propiedades sensoriales usadas para reconocer y usar las especies de Valeriana y O. chilensis. A. monantha y E. paniculatum son reconocidas por sus características morfológicas, aunque también se valoranpor su sabor y aroma. Las observaciones microscópicas revelan la presencia de cavidades secretoras esquizógenas en O. chilensis, E. paniculatum y A. monantha y abundante presencia de almidón. En las especies de Valeriana se observa la peridermiscon elevado contenido de aceites esenciales como gotas. Se concluye que estas cinco especies poseen atributos organolépticos originados en estructuras anatómicas especializadas, los que en parte explicarían sus empleos alimenticios y/o medicinales.

[Births prevalence of 27 selected congenital anomalies in 7 geographic regions of Argentina].

Science.gov (United States)

Campaña, Hebe; Pawluk, Mariela S; López Camelo, Jorge S

2010-10-01

The aim of the present work was to estimate the frequency of 27 birth defects in 7 geographical regions of Argentina. Observational, cross-sectional, descriptive design. A sample of 21,844 new born with birth defects was selected, ascertained from 855,220 births, between 1994 and 2007, in 59 hospitals belonging to the ECLAMC network. In order to identify regions of high frequency a Poisson regression was used, adjusted by different hospitals from the same region. The model included a time variable to detect secular trends and 6 dummy variables for 7 predefined geographical regions: Metropolitana (MET); Pampa (PAM); Centro (CEN); Cuyo (CUY); Noroeste (NOA); Nordeste (NEA) and Patagonia (PAT). High frequencies regional analysis showed the following significant results: PAM: severe hypospadias; CEN: spina bifida, microtia, cleft lip with cleft palate, polycystic kidney, postaxial polydactyly and Down syndrome; CUY: postaxial polydactyly; NOA: omphalocele, gastroschisis, cleft lip without cleft palate, cleft lip with cleft palate, anorectal atresia/stenosis, indeterminate sex, preaxial polydactyly and pectoral agenesis; PAT: cleft lip without cleft palate. Out of the 27 congenital anomalies analyzed, fourteen showed a frequency significatively higher in one or more regions.

Nanofósiles calcáreos paleógenos y biostratigrafía para dos pozos en el este de la Cuenca Austral, Patagonia, Argentina Paleogene calcareous nannofossil biostratigraphy for two boreholes in the eastern Austral Basin, Patagonia, Argentina

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Juan Pablo Pérez Panera

2013-01-01

Full Text Available Calcareous nannofossils from two boreholes (Campo Bola and Sur Río Chico in the subsurface of eastern Austral Basin, Santa Cruz Province, Argentina, allowed the identification of Early to Middle Paleocene, Early to Middle Eocene and Late Eocene to Early Oligocene assemblages. These assemblages match the formations logged in the boreholes Campo Bola, Man Aike and Río Leona respectively, and represent three paleogene sedimentary cycles within the basin. These results permitted the reinterpretation of previous data from an adjacent borehole (Cerro Redondo. The southern boreholes (Cerro Redondo and Sur Río Chico yield an Early to Middle Paleocene calcareous nannofossil assemblage and an almost continuous record of nannofossils from Early Eocene to Early Oligocene. A discontinuity is interpreted by the absence of Late Paleocene assemblages. The northern borehole (Campo Bola yield only late Early Eocene to Early Oligocene assemblages. The data also indicates that the Paleogene beds unconformably overlie Upper Cretaceous strata.El estudio de los nanofósiles calcáreos recuperados en muestras de subsuelo de dos pozos de exploración (Campo Bola y Sur Río Chico en el este de la Cuenca Austral, provincia de Santa Cruz, Argentina, permitió reconocer asociaciones del Paleoceno Temprano a Medio, Eoceno Temprano a Medio y Eoceno Tardío a Oligoceno Temprano. Estas asociaciones son coincidentes con las formaciones atravesadas en los sondeos hechos en Campo Bola, Man Aike y Río Leona, respectivamente, y representan tres ciclos sedimentarios paleógenos dentro de la cuenca. Estos resultados permitieron la reinterpretación de datos previos de un pozo adyacente (Cerro Redondo. Los pozos ubicados al sur (Cerro Redondo y Sur Río Chico contienen asociaciones de nanofósiles calcáreos del Paleoceno Temprano a Medio y un registro prácticamente continuo de nanofósiles del Eoceno Temprano al Oligoceno Temprano. Se interpreta una discontinuidad por ausencia de

CHANDRA OBSERVATION OF THE TeV SOURCE HESS J1834-087

International Nuclear Information System (INIS)

Misanovic, Zdenka; Kargaltsev, Oleg; Pavlov, George G.

2011-01-01

Chandra ACIS observed the field of the extended TeV source HESS J1834-087 for 47 ks. A previous XMM-Newton EPIC observation of the same field revealed a point-like source (XMMU J183435.3-084443) and an offset region of faint extended emission. In the low-resolution, binned EPIC images the two appear to be connected. However, the high-resolution Chandra ACIS images do not support the alleged connection. In these images, XMMU J183435.3-084443 is resolved into a point source, CXOU J183434.9-084443 (L 0.5-8keV ≅ 2.3 x 10 33 erg s -1 , for a distance of 4 kpc; photon index Γ ≅ 1.1), and a compact (∼ 0.5-8keV ≅ 4.1 x 10 33 erg s -1 , Γ ≅ 2.7). The nature of the nebula is uncertain. We discuss a dust scattering halo and a pulsar-wind nebula as possible interpretations. Based on our analysis of the X-ray data, we re-evaluate the previously suggested interpretations of HESS J1834-087 and discuss a possible connection to the Fermi Large Area Telescope source 1FGL J1834.3-0842c. We also obtained an upper limit of 3 x 10 -14 erg cm -2 s -1 on the unabsorbed flux of the SGR J1833-0832 (in quiescence), which happened to be in the ACIS field of view.

Deeper H.E.S.S. observations of Vela Junior (RX J0852.0-4622): Morphology studies and resolved spectroscopy

Science.gov (United States)

H.E.S.S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Angüner, E. O.; Arakawa, M.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Büchele, M.; Bulik, T.; Capasso, M.; Carr, J.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chalme-Calvet, R.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Chrétien, M.; Coffaro, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'C.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khélifi, B.; Kieffer, M.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kolitzus, D.; Komin, Nu.; Krakau, S.; Kraus, M.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Öttl, S.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Paz Arribas, M.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Richter, S.; Rieger, F.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Saito, S.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stycz, K.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Żywucka, N.

2018-04-01

Aims: We study γ-ray emission from the shell-type supernova remnant (SNR) RX J0852.0-4622 to better characterize its spectral properties and its distribution over the SNR. Methods: The analysis of an extended High Energy Spectroscopic System (H.E.S.S.) data set at very high energies (E > 100 GeV) permits detailed studies, as well as spatially resolved spectroscopy, of the morphology and spectrum of the whole RX J0852.0-4622 region. The H.E.S.S. data are combined with archival data from other wavebands and interpreted in the framework of leptonic and hadronic models. The joint Fermi-LAT-H.E.S.S. spectrum allows the direct determination of the spectral characteristics of the parent particle population in leptonic and hadronic scenarios using only GeV-TeV data. Results: An updated analysis of the H.E.S.S. data shows that the spectrum of the entire SNR connects smoothly to the high-energy spectrum measured by Fermi-LAT. The increased data set makes it possible to demonstrate that the H.E.S.S. spectrum deviates significantly from a power law and is well described by both a curved power law and a power law with an exponential cutoff at an energy of Ecut = (6.7 ± 1.2stat ± 1.2syst) TeV. The joint Fermi-LAT-H.E.S.S. spectrum allows the unambiguous identification of the spectral shape as a power law with an exponential cutoff. No significant evidence is found for a variation of the spectral parameters across the SNR, suggesting similar conditions of particle acceleration across the remnant. A simple modeling using one particle population to model the SNR emission demonstrates that both leptonic and hadronic emission scenarios remain plausible. It is also shown that at least a part of the shell emission is likely due to the presence of a pulsar wind nebula around PSR J0855-4644. A FITS image of the region of interest and two text files describing the H.E.S.S. spectrum of RX J0852.0-4622 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http

Flavonols, alkaloids, and antioxidant capacity of edible wild berberis species from patagonia.

Science.gov (United States)

Ruiz, Antonieta; Zapata, Moises; Sabando, Constanza; Bustamante, Luis; von Baer, Dietrich; Vergara, Carola; Mardones, Claudia

2014-12-24

There are 20 species of the Berberidaceae family described in Chile, whose fruits are edible and show high anthocyanin and hydroxycinnamic acid levels. Berberis microphylla G. Forst, commonly known as calafate, is the most extensively distributed. Flavonols and alkaloids in seed, pulp, skin, and whole calafate berry extracts and other Berberis were studied using HPLC-DAD-ESI-MS/MS and HPLC with fluorescence detector. Berry samples from different locations in Chilean Patagonia, including different phenological stages, were systematically addressed. Results were compared with other organs of the plant and with other Berberis species. Total flavonol concentration in calafate (n = 65) was 1.33 ± 0.54 μmol/g. Glycosyl metabolites of quercetin and isorhamnetin were the most abundant. Similar profiles were observed in calafate from distinct locations, but important differences were observed for the other edible Berberis species. Calafate pulp and skin have higher flavonol concentrations than seeds, and the maturation process reduced its levels. TEACCUPRAC and TEACABTS of whole calafate extracts and fractions are also explored. Finally, only berberine was detected in the fruit (0.001%), mainly in seeds. Results contribute to the promotion of this berry as a superfruit from Patagonia.

Little Ice Age advance and retreat of Glaciar Jorge Montt, Chilean Patagonia

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A. Rivera

2012-03-01

Full Text Available Glaciar Jorge Montt (48°20' S/73°30' W, one of the main tidewater glaciers of the Southern Patagonian Icefield (SPI, has experienced the greatest terminal retreat observed in Patagonia during the past century, with a recession of 19.5 km between 1898 and 2011. This retreat has revealed trees laying subglacially until 2003. These trees were dated using radiocarbon, yielding burial ages between 460 and 250 cal yrs BP. The presence of old growth forest during those dates indicates that Glaciar Jorge Montt was upvalley of its present position before the commonly recognized Little Ice Age (LIA period in Patagonia. The post-LIA retreat was most likely triggered by climatically induced changes during the 20th century; however, Glaciar Jorge Montt has responded more dramatically than its neighbours. The retreat of Jorge Montt opened a 19.5 km long fjord since 1898, which reaches depths in excess of 390 m. The bathymetry is well correlated with glacier retreat rates, suggesting that dynamic responses of the glacier are at least partially connected to near buoyancy conditions at the ice front, resulting in high calving fluxes, accelerating thinning rates and rapid ice velocities.

Origin and evolution of the Laguna Potrok Aike maar (Southern Patagonia, Argentina) as revealed by seismic data

Science.gov (United States)

Gebhardt, C.; de Batist, M. A.; Niessen, F.; Anselmetti, F.; Ariztegui, D.; Haberzettl, T.; Ohlendorf, C.; Zolitschka, B.

2009-12-01

Seismic reflection and refraction data provide insights into the sedimentary infill and the underlying volcanic structure of Laguna Potrok Aike, a maar lake situated in the Pali Aike Volcanic Field, Southern Patagonia. The lake has a diameter of ~3.5 km, a maximum water depth of ~100 m and a presumed age of ~770 ka. Its sedimentary regime is influenced by climatic and hydrologic conditions related to the Antarctic Circumpolar Current, the Southern Hemispheric Westerlies and sporadic outbreaks of Antarctic polar air masses. Multiproxy environmental reconstructions of the last 16 ka document that this terminal lake is highly sensitive to climate change. Laguna Potrok Aike has recently become a major focus of the International Continental Scientific Drilling Program and was drilled down to 100 m below lake floor in late 2008 within the PASADO project. The sediments are likely to contain a continental record spanning the last ca. 80 kyrs unique in the South American realm. Seismic reflection data show relatively undisturbed, stratified lacustrine sediments at least in the upper ~100 m of the sedimentary infill but are obscured possibly by gas and/or coarser material in larger areas. A model calculated from seismic refraction data reveals a funnel-shaped structure embedded in the sandstone rocks of the surrounding Santa Cruz Formation. This funnel structure is filled by lacustrine sediments of up to 370 m in thickness. These can be separated into two distinct subunits with low acoustic velocities of 1500-1800 m s-1 in the upper subunit pointing at unconsolidated lacustrine muds, and enhanced velocities of 2000-2350 m s-1 in the lower subunit. Below these lacustrine sediments, a unit of probably volcanoclastic origin is observed (>2400 m s-1). This sedimentary succession is well comparable to other well-studied sequences (e.g. Messel and Baruth maars, Germany), confirming phreatomagmatic maar explosions as the origin of Laguna Potrok Aike.

The hydrogeothermal potential of Southern Hesse; Das hydrogeothermische Potential Suedhessens

Energy Technology Data Exchange (ETDEWEB)

Fitzer, C; Fluhrer, S; Sanner, B; Knoblich, K [Giessen Univ. (Germany). Inst. fuer Angewandte Geowissenschaften

1997-12-01

The paper investigates rock series suited as storage media and the temperature distribution in the subsurface of Southern Hesse. It gives an idea of the possibilities for hydrogeothermal energy use in the area. The densily populated Rhein-Main-region provides a good demand potential for geothermal heat. A substantially elevated geothermal gradient of about 60 K/km as compared to the continental average of 30 K/km could be demonstrated in the northern part of the Upper Rhine Graben. Thermal anomalies could be localised. The Rotliegend-layers (Perm) provide the highest geothermal ressources in the region. In more shallow depth, the Hydrobia layers (Teritary) show reasonable values. To the north, the potential of these series decreases. Hence hydrogeothermal energy use should not be considered in the northern part of Southern Hesse. The highest potential can be expected from the Rotliegend layers in the area of Stockstadt and Biebesheim. (orig.) [Deutsch] Die Untersuchung geht auf die moeglichen Speichergesteine und die Temperaturverteilung im Untergrund Suedhessens ein und gibt einen ersten Eindruck von den Moeglichkeiten zur Nutzung der Hydrogeothermie in der Region. Fuer geothermische Waerme besteht im dicht besiedelten Rhein-Main-Gebiet eine gute Abnehmerstruktur. Im noerdlichen Oberrheingraben konnte im Mittel ein deutlich erhoehter Temperaturgradient von etwa 60 K/km gegenueber dem kontinentalen Krustendurchschnittswert von 30 K/km nachgewiesen werden. Waemeanomalien wurden lokalisiert. Die Rotliegendschichten weisen im untersuchten Gebiet eindeutig die hoechsten Ressourcen auf. In geringerer Tiefenlage erzielen die Hydrobienschichten noch beachtliche Werte. Nach Norden nimmt das Potential der Schichten ab. Daher ist von einer Nutzung der Hydrogeothermie im noerdlichen Bereich Suedhessens eher abzuraten. Die hoechsten Ressourcen in Suedhessen sind im Bereich von Stockstadt und Biebesheim in den Rotliegenschichten zu erwarten. (orig.)

The cephalic lateral line system of temperate perches (Perciformes: Percichthyidae from Argentinean Patagonia

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Rocío M. Vega

Full Text Available ABSTRACT The species of Percichthys (Percichthyidae are endemic to southern South America. Some authors have pointed out that the genus includes four valid species, based on the morphology of the head, jaws, and fins. A phylogenetic analysis published by other authors suggests that three of them are morphotypes belonging to the same species, Percichthys trucha (Valenciennes, 1833. The aim of this study is to describe for the first time the morphology of the cephalic seismosensory system of Patagonian perches, and how these characters vary in the three morphotypes, in order to provide morphological elements to analyze the taxonomy of these fish species. Comparisons of the cephalic seismosensory system between juveniles and adults were also conducted. Juvenile and adult specimens were collected in the northwestern Argentinean Patagonia. Specimens were bleached in 5% H2O2 and the canal systems of their cephalic lateral line were filled with hematoxylin. Specimens were deposited in the Museo Argentino de Ciencias Naturales Bernardino Rivadavia, Argentina. The cephalic lateral line of the studied specimens is a widened type of canal systems, is not connected to the trunk lateral line, and consists of preopercular-mandibular canal, infraorbital canal, supraorbital canal, temporal canal, supratemporal canal, and a supraorbital commisure. The number of pores increases during the ontogeny, while their diameters decrease. The number, position and size of infraorbital canal pores showed significant differences among morphotypes and juveniles. The interpopulation variation regarding the number, position, and size of pores seems to signal an ongoing process of speciation, which is the result adaptations to different environmental conditions. Our study contributes to the knowledge of the morphology of percichthids and describes for the first time the seismosensory system of temperate perches.

The energy spectrum of cosmic-ray electrons measured with H.E.S.S

International Nuclear Information System (INIS)

Egberts, Kathrin

2009-01-01

The spectrum of cosmic-ray electrons has so far been measured using balloon and satellite-based instruments. At TeV energies, however, the sensitivity of such instruments is very limited due to the low flux of electrons at very high energies and small detection areas of balloon/satellite based experiments. The very large collection area of ground-based imaging atmospheric Cherenkov telescopes gives them a substantial advantage over balloon/ satellite based instruments when detecting very-high-energy electrons (> 300 GeV). By analysing data taken by the High Energy Stereoscopic System (H.E.S.S.), this work extends the known electron spectrum up to 4 TeV - a range that is not accessible to direct measurements. However, in contrast to direct measurements, imaging atmospheric Cherenkov telescopes such as H.E.S.S. detect air showers that cosmic-ray electrons initiate in the atmosphere rather than the primary particle. Thus, the main challenge is to differentiate between air showers initiated by electrons and those initiated by the hadronic background. A new analysis technique was developed that determines the background with the support of the machine-learning algorithm Random Forest. It is shown that this analysis technique can also be applied in other areas such as the analysis of diffuse γ rays from the Galactic plane. (orig.)

The energy spectrum of cosmic-ray electrons measured with H.E.S.S.

Energy Technology Data Exchange (ETDEWEB)

Egberts, Kathrin

2009-03-30

The spectrum of cosmic-ray electrons has so far been measured using balloon and satellite-based instruments. At TeV energies, however, the sensitivity of such instruments is very limited due to the low flux of electrons at very high energies and small detection areas of balloon/satellite based experiments. The very large collection area of ground-based imaging atmospheric Cherenkov telescopes gives them a substantial advantage over balloon/ satellite based instruments when detecting very-high-energy electrons (> 300 GeV). By analysing data taken by the High Energy Stereoscopic System (H.E.S.S.), this work extends the known electron spectrum up to 4 TeV - a range that is not accessible to direct measurements. However, in contrast to direct measurements, imaging atmospheric Cherenkov telescopes such as H.E.S.S. detect air showers that cosmic-ray electrons initiate in the atmosphere rather than the primary particle. Thus, the main challenge is to differentiate between air showers initiated by electrons and those initiated by the hadronic background. A new analysis technique was developed that determines the background with the support of the machine-learning algorithm Random Forest. It is shown that this analysis technique can also be applied in other areas such as the analysis of diffuse {gamma} rays from the Galactic plane. (orig.)

A major electronics upgrade for the H.E.S.S. Cherenkov telescopes 1-4

CERN Document Server

Giavitto, G; Balzer, A.; Berge, D.; Brun, F.; Chaminade, T.; Delagnes, E.; Fontaine, G.; Füßling, M.; Giebels, B.; Glicenstein, J.F.; Gräber, T.; Hinton, J.A.; Jahnke, A.; Klepser, S.; Kossatz, M.; Kretzschmann, A.; Lefranc, V.; Leich, H.; Lüdecke, H.; Manigot, P.; Marandon, V.; Moulin, E.; de, M.; Nayman, P.; Penno, M.; Ross, D.; Salek, D.; Schade, M.; Schwab, T.; Simoni, R.; Stegmann, C.; Thornhill, J.; Toussenel, F.

2015-01-01

The High Energy Stereoscopic System (H.E.S.S.) is an array of imaging atmospheric Cherenkov telescopes (IACTs) located in the Khomas Highland in Namibia. It consists of four 12-m telescopes (CT1-4), which started operations in 2003, and a 28-m diameter one (CT5), which was brought online in 2012. It is the only IACT system featuring telescopes of different sizes, which provides sensitivity for gamma rays across a very wide energy range, from ~30 GeV up to ~100 TeV. Since the camera electronics of CT1-4 are much older than the one of CT5, an upgrade is being carried out; first deployment was in 2015, full operation is planned for 2016. The goals of this upgrade are threefold: reducing the dead time of the cameras, improving the overall performance of the array and reducing the system failure rate related to aging. Upon completion, the upgrade will assure the continuous operation of H.E.S.S. at its full sensitivity until and possibly beyond the advent of CTA. In the design of the new components, several CTA con...

Mortalidad infantil por malformaciones congénitas y condición socioeconómica: el caso de la Argentina Infant mortality due to congenital malformations and socioeconomic status: the case of Argentina

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Rubén A. Bronberg

2012-06-01

Full Text Available OBJETIVO: Relacionar la tasa de mortalidad infantil por malformaciones congénitas (TMIMC y el porcentaje de muertes por malformaciones congénitas (%MMC con las características sociodemográficas y económicas en la Argentina. MÉTODOS: La población estudiada de la Argentina reside en 511 departamentos de 23 provincias, agrupadas en cinco regiones geográficas (Noroeste, Noreste, Centro, Cuyo y Patagonía. Las variables analizadas fueron la TMLMC y el %MMC calculados a partir de los nacimientos y las defunciones del quinquenio 2002-2006. Además, se utilizaron 21 variables del Censo de Población y Vivienda del 2001 (Instituto Nacional de Estadística y Censos de Argentina para construir el Indicador Sociodemográfico y Económico (ISDE mediante el análisis de componentes principales. Se realizaron pruebas de comparación para valorar si aparecían diferencias significativas entre las distintas regiones y las correlaciones entre indicadores, y de estos con la latitud y longitud departamental. RESULTADOS: La TMIMC no presentó correlación significativa con el ISDE ni con las coor denadas geográficas. El %MMC y el ISDE presentaron una correlación positiva significativa (P OBJECTIVE: Compare the infant mortality rate due to congenital malformations ( IMRCM and the percentage of deaths due to congenital malformations (%DCM with sociodemographic and economic characteristics in Argentina. METHODS: The Argentine study population resided in 511 departments of 23 provinces, grouped into five geographic regions (Northwest, Northeast, Central, Cuyo, and Patagonia. The analyzed variables were the IMRCM and the %DCM calculated on the basis of births and deaths during 2002-2006 period. In addition, 21 variables were used from the 2001 Population and Housing Census (National Census and Statistics Institute of Argentina to construct the Sociodemographic and Economic Indicator (SDEI through the analysis of principal components. Comparison tests were

Petrogenesis of volcanic rocks that host the world-class Agsbnd Pb Navidad District, North Patagonian Massif: Comparison with the Jurassic Chon Aike Volcanic Province of Patagonia, Argentina

Science.gov (United States)

Bouhier, Verónica E.; Franchini, Marta B.; Caffe, Pablo J.; Maydagán, Laura; Rapela, Carlos W.; Paolini, Marcelo

2017-05-01

We present the first study of the volcanic rocks of the Cañadón Asfalto Formation that host the Navidad world-class Ag + Pb epithermal district located in the North Patagonian Massif, Patagonia, Argentina. These volcanic and sedimentary rocks were deposited in a lacustrine environment during an extensional tectonic regime associated with the breakup of Gondwana and represent the mafic to intermediate counterparts of the mainly silicic Jurassic Chon Aike Volcanic Province. Lava flows surrounded by autobrecciated carapace were extruded in subaerial conditions, whereas hyaloclastite and peperite facies suggest contemporaneous subaqueous volcanism and sedimentation. LA-ICPMS Usbnd Pb ages of zircon crystals from the volcanic units yielded Middle Jurassic ages of 173.9 ± 1.9 Ma and 170.8 ± 3 Ma. In the Navidad district, volcanic rocks of the Cañadón Asfalto Formation show arc-like signatures including high-K basaltic-andesite to high-K dacite compositions, Rb, Ba and Th enrichment relative to the less mobile HFS elements (Nb, Ta), enrichment in light rare earth elements (LREE), Ysbnd Ti depletion, and high Zr contents. These characteristics could be explained by assimilation of crustal rocks in the Jurassic magmas, which is also supported by the presence of zircon xenocrysts with Permian and Middle-Upper Triassic ages (281.3 Ma, 246.5, 218.1, and 201.3 Ma) and quartz xenocrysts recognized in these volcanic units. Furthermore, Sr and Nd isotope compositions suggest a contribution of crustal components in these Middle Jurassic magmas. High-K basaltic andesite has initial 87Sr/86Sr ratios of 0.70416-0.70658 and ξNd(t) values of -5.3 and -4. High-K dacite and andesite have initial 87Sr/86Sr compositions of 0.70584-0.70601 and ξNd(t) values of -4,1 and -3,2. The range of Pb isotope values (206Pb/204Pb = 18.28-18.37, 207Pb/204Pb = 15.61-15.62, and 208Pb/204Pb = 38.26-38.43) of Navidad volcanic rocks and ore minerals suggest mixing Pb sources with contributions of

Unusual shell anatomy and osteohistology in a new Late Cretaceous panchelid turtle from northwestern Patagonia, Argentina

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Marcelo S. De La Fuente

2017-09-01

Full Text Available Rionegrochelys caldieroi de la Fuente, Maniel, and Jannello gen. et sp. nov. is a Late Cretaceous turtle from Rio Negro Province, Argentina. The holotype and the referred specimens of this new species show an unusual shell morphology and microanatomy. The proportion between the carapace and plastron and the peculiar morphology of the shell such as the heart shaped carapace, a very deep nuchal notch, peripheral bones 2–11 with strongly gutter, the first vertebral scute twice as wide as long and subrectangular in shape, the posterior margin of vertebral scute 5 is three lobe shaped, and the unexpected osteohistology characterized by a massive structure, with higher compactness (80.6% than other chelids, suggests beyond doubt that this turtle may be considered a new taxon. A semi-aquatic habitat with tendency towards terrestrial environments is inferred for Rionegrochelys caldieroi similar to that of the extant pelomedusid Pelomedusa subrufa among the extant pleurodires. Rionegrochelys caldieroi is recovered as a stem chelid. This new species seems to be closely related to Bonapartemys bajobarrealis and the clade formed by Lomalatachelys neuquina plus Mendozachelys wichmanni.

Distribution and reproductive biology of the Electric ray Discopyge tschudii Heckel, 1846 in San Matías Gulf, Northern Patagonia, Argentina

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Marilú Estalles

2011-01-01

Full Text Available The Electric ray Discopyge tschudii is distributed in the Southwest Atlantic from southern Brazil to southern Argentina and in the Southeast Pacific from Peru to southern Chile. The main threat to this species is fishing. Discopyge tschudii is noncommercial and individuals caught are discarded on board. The present study analyzes the distribution and the morphological and reproductive characteristics of this ray in San Matías Gulf (SMG, Argentina. A total of 1087 individuals were analyzed. The species presented an aggregate distribution, with the main concentrations in the northern and eastern areas of SMG, at depths below 100 m. Males ranged from 9 to 43 cm and females from 11 to 38 cm. The species presented sexual dimorphism. Males were larger and heavier than females and also matured at larger sizes. Size at 50% of maturity was estimated at 30 cm for males and 21 cm for females. A total of 199 embryos were sampled and the proportion of sexes showed no significant differences from the expected 1:1. The number of embryos per female varied from 1 to 12. The most frequent values were 2 and 5. Length at birth was estimated at 82.17 ± 3.87 mm. Based on our findings, we hypothesize that the electric ray D. tschudii completes its reproductive cycle in SMG.La raya eléctrica Discopyge tschudii se distribuye, en el Atlántico Sudoccidental, desde el sur de Brasil hasta el sur de Argentina y en el Pacifico Sudoriental desde Perú al sur de Chile. La principal amenaza para la especie es la pesca. Es una especie sin valor comercial y debido a esto los ejemplares capturados por las embarcaciones pesqueras son descartados a bordo. En el presente estudio se analizan la distribución espacial y las características morfológicas y reproductivas de la especie en el Golfo San Matías (GSM, Argentina. Un total de 1087 ejemplares fueron analizados. La especie presentó una distribución agregada, encontrándose las principales concentraciones en el sector norte

Very High Energy astronomy from H.E.S.S. to CTA. Opening of a new astronomical window on the non-thermal Universe

International Nuclear Information System (INIS)

Naurois, Mathieu de

2012-01-01

The last ten years saw the emergence of Imaging Atmospheric Cherenkov Telescopes as a mature and efficient technique for the study of the Very High Energy Universe, leading to the successful opening, mainly by the HESS experiment, of our understanding of the non-thermal Universe. This Habilitation thesis summaries ten years of research in Very High Energy gamma-ray astronomy with HESS and CTA. In the first part, instrumental aspects such as the experiment conception, its calibration, the reconstruction of the events and the data analysis are presented. The second parts draws a panorama of the main discoveries in the domain. (author)

Evaluating Effectiveness of Modeling Motion System Feedback in the Enhanced Hess Structural Model of the Human Operator

Science.gov (United States)

Zaychik, Kirill; Cardullo, Frank; George, Gary; Kelly, Lon C.

2009-01-01

In order to use the Hess Structural Model to predict the need for certain cueing systems, George and Cardullo significantly expanded it by adding motion feedback to the model and incorporating models of the motion system dynamics, motion cueing algorithm and a vestibular system. This paper proposes a methodology to evaluate effectiveness of these innovations by performing a comparison analysis of the model performance with and without the expanded motion feedback. The proposed methodology is composed of two stages. The first stage involves fine-tuning parameters of the original Hess structural model in order to match the actual control behavior recorded during the experiments at NASA Visual Motion Simulator (VMS) facility. The parameter tuning procedure utilizes a new automated parameter identification technique, which was developed at the Man-Machine Systems Lab at SUNY Binghamton. In the second stage of the proposed methodology, an expanded motion feedback is added to the structural model. The resulting performance of the model is then compared to that of the original one. As proposed by Hess, metrics to evaluate the performance of the models include comparison against the crossover models standards imposed on the crossover frequency and phase margin of the overall man-machine system. Preliminary results indicate the advantage of having the model of the motion system and motion cueing incorporated into the model of the human operator. It is also demonstrated that the crossover frequency and the phase margin of the expanded model are well within the limits imposed by the crossover model.

The uranium potential of the continental Cretaceous of Patagonia

International Nuclear Information System (INIS)

Olsen, H.; Berizzo, J.

1980-01-01

The geological features of the fluvial sedimentation of the Cretaceous of Patagonia - the Grupo Chubut Formation in the provinces of Chubut and Santa Cruz, underlined this environment as one of high favourability for discovering uranium deposits. The area has been explored by the CNEA who found two outstanding levels of fluvial sediments that are today the target of further studies to find new deposits. The general geological features are given, together with the results of the exploration up to date, distribution of radiometric anomalies, deposits discovered and an estimation of the uraniferous potential of the Formation. (author)

Variability of Soil Types in Wetland Meadows in the South of the Chilean Patagonia Variabilidad de Tipos de Suelos en Las Vegas del Sur de la Patagonia Chilena

OpenAIRE

Ladislava Filipová; Radim Hédl; Nilo Covacevich C.

2010-01-01

The wetland meadows and pastures (vegas) of the agricultural zone of the Magallanes Region and the Chilean Patagonia are productive and intensively exploited ecosystems. However, there is scarce data about the typology and the physical and chemical properties of the soils that determine the agricultural potential of vegas sites. Sampling of the main horizons of 47 soil profiles was conducted throughout the area. The profiles were described in the field and consequently classified according to...

El patrimonio industrial petrolero en la Patagonia: Comodoro Rivadavia (Argentina y Cerro Sombrero (Chile. Una perspectiva comparada

Directory of Open Access Journals (Sweden)

Pía Acevedo Méndez

2016-01-01

Full Text Available El hallazgo de petróleo en Comodoro Rivadavia (Chubut, Argentina y en Manantiales (Tierra del Fuego, lado chileno, motivó la construcción de espacios socioproductivos bajo el modelo de Company Towns. En el caso argentino la empresa estatal Yacimientos Petrolíferos Fiscales (Y.P.F creó el Campamento Central y la Empresa Nacional del Petróleo (ENAP creó Cerro Sombrero en Chile, los que en la década de 1970 formaron dos tejidos urbanos (barrio en el caso argentino y pueblo en el caso chileno. En esta dinámica se transformó el modo de habitar de ambos espacios, que se convirtieron en potenciales elementos turísticos, teniendo en cuenta que desde el año 2014 poseen reconocimiento patrimonial relacionado con su pasado petrolero y su arquitectura moderna. El objetivo es comparar cómo ambas empresas petroleras estatales construyeron dichos espacios “urbanos” y sus comunidades sociolaborales e indagar en la relación identidad/ patrimonio de ypefeanos y enapinos.

Ground level and Lidar monitoring of volcanic dust and dust from Patagonia

Science.gov (United States)

Otero, L. A.; Losno, R.; Salvador, J. O.; Journet, E.; Qu, Z.; Triquet, S.; Monna, F.; Balkanski, Y.; Bulnes, D.; Ristori, P. R.; Quel, E. J.

2013-05-01

A combined approach including ground level aerosol sampling, lidar and sunphotometer measurements is used to monitor suspended particles in the atmosphere at several sites in Patagonia. Motivated by the Puyehue volcanic eruption in June 2011 two aerosol monitoring stations with several passive and active instruments were installed in Bariloche and Comodoro Rivadavia. The main goal which is to monitor ground lifted and transported ashes and dust involving danger to civil aviation, is achieved by measuring continuously aerosol concentration at ground level and aerosol vertical distribution using lidar. In addition, starting from December 2011, continuous series of weekly accumulated aerosol concentrations at Rio Gallegos are being measured to study the impact of Patagonian dust over the open ocean on phytoplankton primary productivity and CO2 removal. These measurements are going to be coupled with LIDAR monitoring and a dust optical response models to test if aerosol extrapolation can be done from the ground to the top of the layer. Laboratory chemical analysis of the aerosols will include elemental composition, solubilisation kinetic and mineralogical determination. Expected deliverables for this study is the estimation of the amount of dust exported from Patagonia towards the South Atlantic, its chemical properties, including bioavailability simulation, from model and comparison to experimental measurements.

The Usefulness of Edible and Medicinal Fabaceae in Argentine and Chilean Patagonia: Environmental Availability and Other Sources of Supply

Directory of Open Access Journals (Sweden)

Soledad Molares

2012-01-01

Full Text Available Fabaceae is of great ethnobotanical importance in indigenous and urban communities throughout the world. This work presents a revision of the use of Fabaceae as a food and/or medicinal resource in Argentine-Chilean Patagonia. It is based on a bibliographical analysis of 27 ethnobotanical sources and catalogues of regional flora. Approximately 234 wild species grow in Patagonia, mainly (60% in arid environments, whilst the remainder belong to Sub-Antarctic forest. It was found that 12.8% (30 species, mainly woody, conspicuous plants, are collected for food or medicines. Most of the species used grow in arid environments. Cultivation and purchase/barter enrich the Fabaceae offer, bringing it up to a total of 63 species. The richness of native and exotic species, and the existence of multiple strategies for obtaining these plants, indicates hybridization of knowledge and practices. Only 22% of the total species used are mentioned in bothcontexts of food and medicine, reflecting low-use complementation. This study suggests a significant ecological appearance and a high level of availability in shops and exchange networks in Patagonia, highlighting the need to consider the full set of environmental and socioeconomic factors in research related to the use and cultural importance of plants in regional contexts.

The Usefulness of Edible and Medicinal Fabaceae in Argentine and Chilean Patagonia: Environmental Availability and Other Sources of Supply

Science.gov (United States)

Molares, Soledad; Ladio, Ana

2012-01-01

Fabaceae is of great ethnobotanical importance in indigenous and urban communities throughout the world. This work presents a revision of the use of Fabaceae as a food and/or medicinal resource in Argentine-Chilean Patagonia. It is based on a bibliographical analysis of 27 ethnobotanical sources and catalogues of regional flora. Approximately 234 wild species grow in Patagonia, mainly (60%) in arid environments, whilst the remainder belong to Sub-Antarctic forest. It was found that 12.8% (30 species), mainly woody, conspicuous plants, are collected for food or medicines. Most of the species used grow in arid environments. Cultivation and purchase/barter enrich the Fabaceae offer, bringing it up to a total of 63 species. The richness of native and exotic species, and the existence of multiple strategies for obtaining these plants, indicates hybridization of knowledge and practices. Only 22% of the total species used are mentioned in bothcontexts of food and medicine, reflecting low-use complementation. This study suggests a significant ecological appearance and a high level of availability in shops and exchange networks in Patagonia, highlighting the need to consider the full set of environmental and socioeconomic factors in research related to the use and cultural importance of plants in regional contexts. PMID:22194774

The IAF's Argentine Grantees: Caught in the Crisis. Indigenous Awakening; Self-Help and the Cities; Storm Clouds and Hope on the Pampa.

Science.gov (United States)

Durbin, Paula

2003-01-01

Examines how Inter-American Foundation's grantees in Argentina are coping with the country's economic crisis of 2001. Describes community development projects in Indigenous regions, the role of urban schools as the only functioning public institution providing human services, literacy education in Patagonia, job training and support for…

The Use of Genetics for the Management of a Recovering Population: Temporal Assessment of Migratory Peregrine Falcons in North America

Science.gov (United States)

2010-11-01

Alaska; Tanana River, Alaska; Porcupine River, Alaska; Yukon, Canada. 5Quebec, Newfoundland, and Labrador, Canada. 6Patagonia, Argentina. 7significant Fis...population decline. Biology Letters 2: 316–319. 102. Halbert ND, Derr JN (2008) Patterns of genetic variation in US federal bison herds . Molecular Ecology 17

Study of extragalactic sources with H.E.S.S

International Nuclear Information System (INIS)

Giebels, Berrie

2007-01-01

The field of Very High Energy (VHE) γ-ray emitting extragalactic sources has considerably evolved since the new generation of atmospheric Cerenkov telescopes (ACT) of improved sensitivity, such as H.E.S.S. array and the MAGIC ACT, have started operating. This has led to a wealth of new clues about emission mechanisms at high energy through the discovery of new sources, more accurate spectra and temporal studies of sources known previously, and simultaneous multi-wavelength (MWL) campaigns since broad band variability is a key phenomenon to the underlying physical mechanisms at play. The fact that some of these new sources are located at redshifts close to z ∼ 0.2 makes them powerful probes of the Extragalactic Background Light (EBL) through the attenuation of γ-rays above 100 GeV

Status and conservation of the ruddy-headed goose Chloephaga rubidiceps Sclater (Aves, Anatidae in its wintering grounds (Province of Buenos Aires, Argentina Estado y conservación del cauquén colorado Chloephaga rubidiceps Sclater (Aves, Anatidae en su zona de invernada (Provincia de Buenos Aires, Argentina

Directory of Open Access Journals (Sweden)

DANIEL E BLANCO

2003-03-01

Full Text Available ABSTRACT The mainland population of the ruddy-headed goose (Chloephaga rubidiceps breeds in southern Patagonia and winters in the south of Buenos Aires province (Argentina, with a recent estimated size at around 900 individuals. This population is considered "in danger of extinction", while the Malvinas (Falkland Islands population is in well conservation status, with an estimated size of 40,000 birds. The aim of this work is to contribute with updated information about the ruddy-headed goose's population wintering in southern Buenos Aires province. The specific objectives were to better delimit its wintering area, to look for sites with large numbers, to study its habitat used, and to identify main threats to the species. Two intensive surveys were conducted during the austral winter of 1999. The results: (1 confirm the low abundance of the ruddy-headed goose supporting its critical conservation status, (2 corroborate its very restricted distribution, with more than 80 % of sightings concentrated in an area of 13,000 ha in southern Buenos Aires province, and (3 suggest that changes in the species' habitat use during the wintering season appear to be a response to changes in habitat availability, resulting from the growth of crops and pastures. The overlap between the species wintering distribution and the main wheat cropping areas of Argentina results in serious threats to this goose. Management actions are discussed to contribute to the conservation of this endangered species.La población continental del Cauquén colorado (Chloephaga rubidiceps cría en el sur de la Patagonia e inverna en el sur de la provincia de Buenos Aires (Argentina, con un tamaño poblacional estimado recientemente en alrededor de 900 individuos. Esta población está considerada "en peligro de extinción", mientras la población de las Islas Malvinas se mantiene en buen estado de conservación, con un tamaño estimado en 40.000 individuos. La meta de este trabajo es

NuSTAR Discovery Of A Young, Energetic Pulsar Associated with the Luminous Gamma-Ray Source HESS J1640-465

Science.gov (United States)

Gotthelf, E. V.; Tomsick, J. A.; Halpern, J. P.; Gelfand, J. D.; Harrison, F. A.; Boggs, S. E.; Christensen, F. E.; Craig, W. W.; Hailey, J. C.; Kaspi, V. M.;

Uses of instrumental neutron activation analysis (INAA) for lichen as bio indicators of environmental contamination

International Nuclear Information System (INIS)

Arribere, M.; Guevara, S.R.; Calvelo, S.

1994-01-01

Three species of epiphytic lichens were sampled at NW Patagonia, Argentina, from urban and peripherical forest area environments Sixty lichen samples were analysed individually by Instrumental Neutron Activation Analysis (INAA). The elements present in the samples were determined by parametric methods at the Neutron Activation Laboratory at Centro Atomico Bariloche, Argentina. All concentration values were normalized to Al concentration. The average normalized concentrations for each element, discriminated by species and environment, are presented in this work. (author). 11 refs, 6 tabs

Estado actual del conocimiento de la familia Ceratopogonidae en la Patagonia (Diptera: Nematocera

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Gustavo R. SPINELLI

2009-01-01

Full Text Available Ceratopogonidae incluye pequeños dípteros nematocerosque crían en hábitats acuáticos o semiacuáticos. Hasta los ‘80, el conocimiento de su taxonomía en la Patagonia se hallaba limitado a la contribución de los comienzos de los ‘30 de Ingram y Macfie, sobre la base de material capturado en 1926-27, en el área del Parque Nacional Nahuel Huapi y zonas vecinasde Chile. En los últimos 25 años, se pusieron en marcha diferentes proyectos, resultando la descripción o registro de numerosos taxones para la región. Si se contabilizan los datos publicados, 102 especies habitan en la Patagonia, de las cuales 86 (84,31% son endémicas para la región. Este alto porcentaje es evidente en los bosques de Nothofagus, con 71 especies endémicas de estebioma, nueve lo son de la estepa y seis presentan registros en bosque y estepa. Datos aún no publicados concuerdan con este esquema. Diecinueve géneros están representados en la Patagonia, diez de ellos con amplia distribución,tres de distribución transantártica y seis son endémicos para el área. Para la misma, se hallan publicadas las revisiones de Forcipomyia, Atrichopogon, Borkenthelea, Macrurohelea y Paradasyhelea; se han finalizado y aún no publicado aquellas de Dasyhelea y Palpomyia, está muy avanzada la de Stilobezzia y se prevé comenzar con las de Austrohelea, Austrosphaeromias, Physohelea y Bezzia. Se calcula que estos datos no divulgados contienen al menos 55 especies todavía no descriptas. Con respecto a los aspectos biogeográficos se pueden destacar estudios que tienden a establecer relaciones entre las áreas reconocidas en esquemas biogeográficos propuestos para la región andina.

Is HESS J1912+101 Associated with an Old Supernova Remnant?

Energy Technology Data Exchange (ETDEWEB)

Su, Yang; Zhou, Xin; Yang, Ji; Chen, Xuepeng; Gong, Yan; Zhang, Shaobo [Purple Mountain Observatory and Key Laboratory of Radio Astronomy, Chinese Academy of Sciences, Nanjing 210008 (China); Chen, Yang, E-mail: yangsu@pmo.ac.cn [Department of Astronomy, Nanjing University, Nanjing 210023 (China)

2017-08-10

HESS J1912+101 is a shell-like TeV source that has no clear counterpart in multiwavelength. Using CO and H i data, we reveal that V {sub LSR} ∼ +60 km s{sup −1} molecular clouds (MCs), together with shocked molecular gas and high-velocity neutral atomic shells, are concentrated toward HESS J1912+101. The prominent wing profiles up to V {sub LSR} ∼ +80 km s{sup −1} seen in {sup 12}CO ( J = 1–0 and J = 3–2) data, as well as the high-velocity expanding H i shells up to V {sub LSR} ∼ +100 km s{sup −1}, exhibit striking redshifted-broadening relative to the quiescent gas. These features provide compelling evidences for large-scale perturbation in the region. We argue that the shocked MCs and the high-velocity H i shells may originate from an old supernova remnant (SNR). The distance to the SNR is estimated to be ∼4.1 kpc based on the H i self-absorption method, which leads to a physical radius of 29.0 pc for the ∼(0.7–2.0) × 10{sup 5} years old remnant with an expansion velocity of ≳40 km s{sup −1}. The +60 km s{sup −1} MCs and the disturbed gas are indeed found to coincide with the bright TeV emission, supporting the physical association between them. Naturally, the shell-like TeV emission comes from the decay of neutral pions produced by interactions between the accelerated hadrons from the SNR and the surrounding high-density molecular gas.

Pasado y presente del uso de plantas silvestres con órganos subterráneos de almacenamiento comestibles en la Patagonia

Directory of Open Access Journals (Sweden)

Juan J. Ochoa

2011-07-01

Full Text Available El presente trabajo es la primara aproximación acerca del papel de las plantas con órganos de almacenamiento subterráneos comestibles (POAS en la Patagonia, desde una perspectiva temporal y espacial, al integrar datos etnohistóricos y etnográficos actuales ligados al uso de las POAS. El 75 % de las 54 fuentes analizadas mencionan el uso de POAS en la alimentación humana de la Patagonia. Las POAS silvestres comestibles registradas ascienden a 51 especies, siendo mayor el conjunto de POAS con raíces comestibles. La estepa y zonas ecotonales resultaron las de mayor riqueza de POAS, probablemente vinculado a adaptaciones ecológicas de éstas a la aridez en el primer caso, como a la alta diversidad relativa que presentan los ecotonos, en el segundo. El registro etnohistórico mostró discontinuidades marcadas, siendo pocas las especies presentes por más de un siglo, destacándose la continuidad documental de A. tuberosa desde el siglo XVIII al presente, así como la incorporación reciente de especies exóticas. Las fuentes etnohistóricas revisadas y su contraste con datos etnobotánicos recientes de campo sugieren dinamismo en los patrones de utilización, que a lo largo del tiempo han llevado al abandono del uso de las POAS en la práctica alimentaria de la Patagonia. Las singularidades encontradas respecto a lo temporal y espacial pueden vincularse tanto a los conocimientos locales y específicos desarrollados a lo largo del tiempo por los habitantes de la Patagonia, como también a las circunstancias sociopolíticas y académicas de cada una de las fuentes analizadas.

New foliicolous species of Cladosporium from South America

NARCIS (Netherlands)

Schubert, K.; Greslebin, A.; Groenewald, J.Z.; Crous, P.W.

2009-01-01

Two new species of Cladosporium found on necrotic needles of Pinus ponderosa trees in Patagonia, Argentina, are described as C. chubutense and C. pini-ponderosae. An additional isolate from dead leaves of Cortaderia collected in Colombia, which is a sister taxon to the species occurring on Pinus, is

H.E.S.S. Limits on Linelike Dark Matter Signatures in the 100 GeV to 2 TeV Energy Range Close to the Galactic Center.

Science.gov (United States)

Abdalla, H; Abramowski, A; Aharonian, F; Ait Benkhali, F; Akhperjanian, A G; Andersson, T; Angüner, E O; Arrieta, M; Aubert, P; Backes, M; Balzer, A; Barnard, M; Becherini, Y; Becker Tjus, J; Berge, D; Bernhard, S; Bernlöhr, K; Birsin, E; Blackwell, R; Böttcher, M; Boisson, C; Bolmont, J; Bordas, P; Bregeon, J; Brun, F; Brun, P; Bryan, M; Bulik, T; Capasso, M; Carr, J; Casanova, S; Chakraborty, N; Chalme-Calvet, R; Chaves, R C G; Chen, A; Chevalier, J; Chrétien, M; Colafrancesco, S; Cologna, G; Condon, B; Conrad, J; Couturier, C; Cui, Y; Davids, I D; Degrange, B; Deil, C; Devin, J; deWilt, P; Djannati-Ataï, A; Domainko, W; Donath, A; Drury, L O'C; Dubus, G; Dutson, K; Dyks, J; Dyrda, M; Edwards, T; Egberts, K; Eger, P; Ernenwein, J-P; Eschbach, S; Farnier, C; Fegan, S; Fernandes, M V; Fiasson, A; Fontaine, G; Förster, A; Funk, S; Füßling, M; Gabici, S; Gajdus, M; Gallant, Y A; Garrigoux, T; Giavitto, G; Giebels, B; Glicenstein, J F; Gottschall, D; Goyal, A; Grondin, M-H; Grudzińska, M; Hadasch, D; Hahn, J; Hawkes, J; Heinzelmann, G; Henri, G; Hermann, G; Hervet, O; Hillert, A; Hinton, J A; Hofmann, W; Hoischen, C; Holler, M; Horns, D; Ivascenko, A; Jacholkowska, A; Jamrozy, M; Janiak, M; Jankowsky, D; Jankowsky, F; Jingo, M; Jogler, T; Jouvin, L; Jung-Richardt, I; Kastendieck, M A; Katarzyński, K; Katz, U; Kerszberg, D; Khélifi, B; Kieffer, M; King, J; Klepser, S; Klochkov, D; Kluźniak, W; Kolitzus, D; Komin, Nu; Kosack, K; Krakau, S; Kraus, M; Krayzel, F; Krüger, P P; Laffon, H; Lamanna, G; Lau, J; Lees, J-P; Lefaucheur, J; Lefranc, V; Lemière, A; Lemoine-Goumard, M; Lenain, J-P; Leser, E; Liu, R; Lohse, T; Lorentz, M; Lypova, I; Marandon, V; Marcowith, A; Mariaud, C; Marx, R; Maurin, G; Maxted, N; Mayer, M; Meintjes, P J; Meyer, M; Mitchell, A M W; Moderski, R; Mohamed, M; Morå, K; Moulin, E; Murach, T; de Naurois, M; Niederwanger, F; Niemiec, J; Oakes, L; O'Brien, P; Odaka, H; Ohm, S; Ostrowski, M; Öttl, S; Oya, I; Padovani, M; Panter, M; Parsons, R D; Paz Arribas, M; Pekeur, N W; Pelletier, G; Perennes, C; Petrucci, P-O; Peyaud, B; Pita, S; Poon, H; Prokhorov, D; Prokoph, H; Pühlhofer, G; Punch, M; Quirrenbach, A; Raab, S; Reimer, A; Reimer, O; Renaud, M; de Los Reyes, R; Rieger, F; Romoli, C; Rosier-Lees, S; Rowell, G; Rudak, B; Rulten, C B; Sahakian, V; Salek, D; Sanchez, D A; Santangelo, A; Sasaki, M; Schlickeiser, R; Schüssler, F; Schulz, A; Schwanke, U; Schwemmer, S; Settimo, M; Seyffert, A S; Shafi, N; Shilon, I; Simoni, R; Sol, H; Spanier, F; Spengler, G; Spies, F; Stawarz, Ł; Steenkamp, R; Stegmann, C; Stinzing, F; Stycz, K; Sushch, I; Tavernet, J-P; Tavernier, T; Taylor, A M; Terrier, R; Tibaldo, L; Tluczykont, M; Trichard, C; Tuffs, R; van der Walt, J; van Eldik, C; van Soelen, B; Vasileiadis, G; Veh, J; Venter, C; Viana, A; Vincent, P; Vink, J; Voisin, F; Völk, H J; Vuillaume, T; Wadiasingh, Z; Wagner, S J; Wagner, P; Wagner, R M; White, R; Wierzcholska, A; Willmann, P; Wörnlein, A; Wouters, D; Yang, R; Zabalza, V; Zaborov, D; Zacharias, M; Zdziarski, A A; Zech, A; Zefi, F; Ziegler, A; Żywucka, N

2016-10-07

A search for dark matter linelike signals iss performed in the vicinity of the Galactic Center by the H.E.S.S. experiment on observational data taken in 2014. An unbinned likelihood analysis iss developed to improve the sensitivity to linelike signals. The upgraded analysis along with newer data extend the energy coverage of the previous measurement down to 100 GeV. The 18 h of data collected with the H.E.S.S. array allow one to rule out at 95% C.L. the presence of a 130 GeV line (at l=-1.5°, b=0° and for a dark matter profile centered at this location) previously reported in Fermi-LAT data. This new analysis overlaps significantly in energy with previous Fermi-LAT and H.E.S.S. No significant excess associated with dark matter annihilations was found in the energy range of 100 GeV to 2 TeV and upper limits on the gamma-ray flux and the velocity weighted annihilation cross section are derived adopting an Einasto dark matter halo profile. Expected limits for present and future large statistics H.E.S.S. observations are also given.

Argentina

International Nuclear Information System (INIS)

Tanis, S.; Ramberg, B.

1990-01-01

Argentina has embarked on an ambitious domestic nuclear research and energy program. The venture promises to provide the nation with the infrastructure to play an important role in the nuclear export market in the years ahead. Buenos Aires built its program on a foundation of international support and assistance that overlay an emerging sophisticated industrial and scientific establishment. The foreign contribution sensitized Argentina to opportunities in the global market. This paper reports that Argentina operates two heavy-water/natural uranium reactors, Atucha I and Embalse. Producing, respectively, 320 MW(e) and 600 MW(e), they supply roughly 10 percent of the country's electricity. With a capacity factor of 84 percent, Atucha I is among the best operated plants in the world. Plans call for a third, 745 MW(e) power plant, Atucha II, to go on line in the early 1990s. During this period, construction also may begin on three 300 MW(e) plants, although the country's foreign indebtedness plus cost overruns in earlier construction will place a heavy burden on these plans

Hydroclimatic conditions trigger record harmful algal bloom in western Patagonia (summer 2016)

OpenAIRE

León-Muñoz, Jorge; Urbina, Mauricio A.; Garreaud, René; Iriarte, José Luis

2018-01-01

A harmful algal bloom (HAB) of the raphidophyta alga Pseudochattonella cf. verruculosa during the 2016 austral summer (February-March) killed nearly 12% of the Chilean salmon production, causing the worst mass mortality of fish and shellfish ever recorded in the coastal waters of western Patagonia. The HAB coincided with a strong El Niño event and the positive phase of the Southern Annular Mode that altered the atmospheric circulation in southern South America and the adjacent Pacific Ocean. ...

Bernard J. Wood Receives 2013 Harry H. Hess Medal: Response

Science.gov (United States)

Wood, Bernard J.

2014-01-01

President Finn, friends, and colleagues, I am truly delighted to accept the Hess Medal for 2013. It is difficult to express one's feelings adequately on receipt of such a prestigious award, but a mixture of pride, humility, and thankfulness for a long and lucky career all occur. It did not start propitiously as my high school grades would only ensure undergraduate entry into the Northern Polytechnic, a second-tier institution in London. Nevertheless, I was enthused by several great teachers, including John Charalambous (inorganic chemistry) and Stephen Morel, a field geologist who had worked for many years in Malawi. They pushed me into trying for graduate school, and I was fortunate to find the eclectic Roger Strens my supervisor at Newcastle.

OPTICAL FLOW APPLIED TO TIME-LAPSE IMAGE SERIES TO ESTIMATE GLACIER MOTION IN THE SOUTHERN PATAGONIA ICE FIELD

Directory of Open Access Journals (Sweden)

E. Lannutti

2016-06-01

Full Text Available In this work, we assessed the feasibility of using optical flow to obtain the motion estimation of a glacier. In general, former investigations used to detect glacier changes involve solutions that require repeated observations which are many times based on extensive field work. Taking into account glaciers are usually located in geographically complex and hard to access areas, deploying time-lapse imaging sensors, optical flow may provide an efficient solution at good spatial and temporal resolution to describe mass motion. Several studies in computer vision and image processing community have used this method to detect large displacements. Therefore, we carried out a test of the proposed Large Displacement Optical Flow method at the Viedma Glacier, located at South Patagonia Icefield, Argentina. We collected monoscopic terrestrial time-lapse imagery, acquired by a calibrated camera at every 24 hour from April 2014 until April 2015. A filter based on temporal correlation and RGB color discretization between the images was applied to minimize errors related to changes in lighting, shadows, clouds and snow. This selection allowed discarding images that do not follow a sequence of similarity. Our results show a flow field in the direction of the glacier movement with acceleration in the terminus. We analyzed the errors between image pairs, and the matching generally appears to be adequate, although some areas show random gross errors related to the presence of changes in lighting. The proposed technique allowed the determination of glacier motion during one year, providing accurate and reliable motion data for subsequent analysis.

LA CUEVA ALIHUÉN, NUEVOS REGISTROS DE PINTURAS RUPESTRES EN LA VEGA DE MAIPÚ (SAN MARTÍN DE LOS ANDES, PATAGONIA, ARGENTINA (The Alihuén Cave, New Records of Cave Paintings in the Maipú Valley (San Martín de los Andes, Patagonia, Argentina

Directory of Open Access Journals (Sweden)

Alberto Enrique Pérez

2014-06-01

Full Text Available Se presenta el resultado de las nuevas investigaciones de pinturas rupestres en la vega Maipú, San Martín de los Andes, Neuquén, Argentina; donde se destaca la presencia de motivos zoomorfos, especialmente camélidos, de escasa representación hasta la fecha en el registro zooarqueológico local. El sitio Cueva Alihuén amplía la diversidad de motivos y técnicas de las pinturas rupestres de la vega Maipú, lo que nos permite plantear aspectos tanto biogeográficos respecto a la fauna como sobre la circulación de información y movilidad. Ambos aspectos nos permiten, nuevamente, aunar ambas vertientes de la cordillera de los Andes, compartiendo, integrando y complementando cada vez más características con el resto de los sitios que componen la cuenca hidrográfica de Valdivia, cuyo sector inferior constituye nuestra área de estudio. ENGLISH: New results from research on the cave paintings of the Maipú Valley, San Martín de los Andes, Neuquén, Argentina, highlight the presence of zoomorphic motifs, especially camelids which have been underrepresented in the local zooarchaeological record. The Alihuén cave site expands the range of motifs and techniques known from the cave paintings of the Maipú Valley that allows us to raise issues regarding both biogeographic wildlife, and on the flow of information and human mobility. These aspects allow us to share and integrate the increasingly complementary features on both sides of the Andes with the rest of the sites that comprise the Valdivia River basin, whose lower section composed our study area.

The H.E.S.S. Galactic plane survey

Science.gov (United States)

H. E. S. S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Benkhali, F. Ait; Angüner, E. O.; Arakawa, M.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Tjus, J. Becker; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bonnefoy, S.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Büchele, M.; Bulik, T.; Capasso, M.; Carrigan, S.; Caroff, S.; Carosi, A.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Colafrancesco, S.; Condon, B.; Conrad, J.; Davids, I. D.; Decock, J.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'C.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Emery, G.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gallant, Y. A.; Garrigoux, T.; Gast, H.; Gaté, F.; Giavitto, G.; Giebels, B.; Glawion, D.; Glicenstein, J. F.; Gottschall, D.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holch, T. L.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khélifi, B.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Malyshev, D.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Ndiyavala, H.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Paz Arribas, M.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poireau, V.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Rauth, R.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Rieger, F.; Rinchiuso, L.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Safi-Harb, S.; Sahakian, V.; Saito, S.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schandri, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Shiningayamwe, K.; Simoni, R.; Sol, H.; Spanier, F.; Spir-Jacob, M.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Steppa, C.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsirou, M.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Zorn, J.; Żywucka, N.

2018-04-01

We present the results of the most comprehensive survey of the Galactic plane in very high-energy (VHE) γ-rays, including a public release of Galactic sky maps, a catalog of VHE sources, and the discovery of 16 new sources of VHE γ-rays. The High Energy Spectroscopic System (H.E.S.S.) Galactic plane survey (HGPS) was a decade-long observation program carried out by the H.E.S.S. I array of Cherenkov telescopes in Namibia from 2004 to 2013. The observations amount to nearly 2700 h of quality-selected data, covering the Galactic plane at longitudes from ℓ = 250° to 65° and latitudes |b|≤ 3°. In addition to the unprecedented spatial coverage, the HGPS also features a relatively high angular resolution (0.08° ≈ 5 arcmin mean point spread function 68% containment radius), sensitivity (≲1.5% Crab flux for point-like sources), and energy range (0.2-100 TeV). We constructed a catalog of VHE γ-ray sources from the HGPS data set with a systematic procedure for both source detection and characterization of morphology and spectrum. We present this likelihood-based method in detail, including the introduction of a model component to account for unresolved, large-scale emission along the Galactic plane. In total, the resulting HGPS catalog contains 78 VHE sources, of which 14 are not reanalyzed here, for example, due to their complex morphology, namely shell-like sources and the Galactic center region. Where possible, we provide a firm identification of the VHE source or plausible associations with sources in other astronomical catalogs. We also studied the characteristics of the VHE sources with source parameter distributions. 16 new sources were previously unknown or unpublished, and we individually discuss their identifications or possible associations. We firmly identified 31 sources as pulsar wind nebulae (PWNe), supernova remnants (SNRs), composite SNRs, or gamma-ray binaries. Among the 47 sources not yet identified, most of them (36) have possible

Exploration for uranium in Argentina: New policies of reactivation

International Nuclear Information System (INIS)

Bianchi, R.E.

2009-01-01

Full text: The policy established by the National Government of Argentina in August 2006 related to resuming the Nuclear activity in the country, lead the CNEA trough the Exploration of Raw Materials Manager (ERMM) to establish working strategies for the next 10 years. These strategies together with the assignment of an adequate budget will contribute to define new uranium resources, which together with the already known ones, will be used to supply the requirements of Nuclear Power and Research Plants in the future. Thus, the ERMM is applying a policy of human resources hiring new personnel in order to count with the minimum necessary workforce to reach these tasks. In Argentina known U resources are related to sedimentary, igneous and metamorphic environments. Considering the geology of the different regions, Argentina has been divided into 57 units in which the geological, geochemical, mineralogical and structural information is evaluated in order to estimate the uranium geological favorability of each unit. The final pursuit of this regional study is to circumscribe new areas with anomalous uranium contents in which prospection and exploration should be carried out. These studies together with prospection and exploration works are performed in the country by four exploration centers based in Salta (RN), Cordoba (R.Ce), Mendoza (R.Cu) and Trelew (RP). The works planned for each exploration center includes: Regional Noroeste, Mina Franca Deposit: peri-granitic vein- type mineralization: 25% of surface exploration has been performed. Mineralized areas: Istataco and San Buenaventura correspond to an igneous-metamorphic environment, Sierra de Vaqueria to a sedimentary one: Prospection stage. Regional Centro, Mineralized areas: El Gallo: drilling stage and Donato: prospection stage, correspond to an igneous-metamorphic environment with intra and peri-granitic anomalies. Noya: prospection stage, sedimentary environment. Regional Cuyo, Mineralized area: Western Sierra

Dynamic Analysis of a Hybrid Energy Storage System (H-ESS Coupled to a Photovoltaic (PV Plant

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Linda Barelli

2018-02-01

Full Text Available Nowadays energy storage is strongly needed to allow grid safety and stability due to the wide penetration of renewable plants. Mainly economic and technological issues impede a relevant integration of conventional storage devices in the energy system. In this scenario, the hybridization of different storage technologies can be a techno-economic solution useful to overcome these issues and promote their diffusion. Hybridization allows multi-operation modes of the Energy Storage System (ESS, merging the positive features of base-technologies and extending their application ranges. This paper provides a dynamic analysis of a hybrid energy storage system (H-ESS consisting of a flywheel and a battery pack coupled to a photovoltaic generation plant and a residential load up to 20 kW. A dynamic model of the overall micro-grid (MG was developed implementing the H-ESS preliminary sizing and a suitable management algorithm. The instantaneous behavior of each component was evaluated. A brief summary of the MG performance at different weather and load conditions was provided together with a characterization of the impact of power fluctuations on the battery current and on the power exchange with the grid.

Deep H.E.S.S. observations of the supernova remnant RX J0852.0-4622

Science.gov (United States)

Sushch, Iurii; Paz Arribas, Manuel; Komin, Nukri; Schwanke, Ullrich

2016-06-01

The largest TeV source, RX J0852.0-4622 (Vela Jr.), is one of the few supernova remnants (SNRs) with well resolved shell-like morphology at very-high-energy (VHE; E>100 GeV) gamma-rays. Strong non-thermal emission across the electromagnetic spectrum from radio to VHE gamma-rays, young age and proximity of the remnant makes it one of the prime objects for the study of particle acceleration aiming to test the paradigm of SNRs being sources of Galactic cosmic rays. Here we present deep H.E.S.S. observations of RX J0852.0-4622 with roughly doubled exposure comparing to previously published results. Improved statistics together with new analysis techniques result in a firm determination of the cut-off in the gamma-ray spectrum and allow the spatially resolved spectroscopy studies. A smooth connection of the H.E.S.S. spectrum to the spectrum at GeV energies as reported by Fermi/LAT provides an exciting opportunity to recover the present-time parent particle population in both leptonic and hadronic scenarios directly from the gamma-ray data alone. These new observations provide us a deeper insight and better understanding of the physical processes in SNRs.

Mio-Pliocene glaciations of Central Patagonia: New evidence and tectonic implications Glaciaciones mio-pliocenas en Patagonia central: nueva evidencia e implicancias tectónicas

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Yves Lagabrielle

2010-07-01

Full Text Available Patagonia is well known for spectacular oceurrences of a variety of glacial-derived landforms and deposits and for a long history of ancient glaciations. In this paper, we first review the diverse evidence that demonstrates the development of glacial-related sedimentary units within the Central Patagonian Cordillera since 7 Ma. Well preserved glacial landforms at the top surface of mesetas on both sides of the Lago General Carrera-Buenos Aires are described: the Meseta Guenguel to the north, and the volcanic Meseta del Lago Buenos Aires to the south. The latter meseta corresponds to a 3 Ma old, morphologically inverted paleo-piedmont, based on Ar/Ar dates of the uppermost lava flows. It shows evidence of glacier advances to the NE direction. Over a distance of 20 km, glacial landforms observed by remote sensing data and digital elevation model define glacial tongues that were fed by the Cordillera reliefs to the west. These lobes are now beheaded from their westward sources along a morpho-structural corridor that bounds the Meseta del Lago Buenos Aires to the west. These remnants can be correlated with the oldest glacial landforms recognized north of Lago General Carrera-Buenos Aires, on the Meseta Guenguel that form the Chipanque moraine system. From these features it is concluded that the glacial drainage network of Central Patagonia has been strongly modified following relief inversion in response to erosion processes and to tectonic causes. Changes occurred after 3 Ma, from a smooth piedmont surface covered by an extensive ice mantle ending with ampie glacial lobes, to the current series of deeply incised glacial valleys such as the Lago General Carrera-Buenos Aires depression. These new data bear important con-straints on the history and development of the first glaciations in southern South America.Patagonia es bien conocida por una espectacular geomorfología glacial y por una larga historia de antiguas glaciaciones. En este art

NPP Grassland: Pampa De Leman, Argentina, 1980-1982, R1

Data.gov (United States)

National Aeronautics and Space Administration — This data set contains two ASCII files (.txt format). One file contains monthly productivity data measured on an arid dwarf-shrub steppe in northern Patagonia,...

Inter-subjectivity and Domestication in the Making of a Global Region: Territorialization of Salmon in the Chilean Patagonia.

NARCIS (Netherlands)

Blanco, Gustavo; Arce, A.M.G.; Fisher, E.F.

2016-01-01

This article examines transformations in the Chilean Patagonia, a region that has become a world leader in Salmon production for global markets. Employing ethnographic methods, this study examines the possibilities of considering inter-subjectivities in the processes of conforming important regions

Living in an estuary: Commerson's dolphin (Cephalorhynchus commersonii (Lacépède, 1804, habitat use and behavioural pattern at the Santa Cruz River, Patagonia, Argentina

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Rocio Loizaga de Castro

2013-11-01

Full Text Available Commerson's dolphins, Cephalorhynchus commersonii, suffer bycatch in fisheries and are target of dolphin-watching activities along Patagonia. Here we described dolphins' habitat use and behavioural pattern at the estuary of Santa Cruz River. Behavioural observations were made from vantage points using a spotting scope. Boat surveys were conducted randomly from Puerto Santa Cruz to the mouth of the river to analyze the habitat use. The survey area was divided into 1 km² cells and characterized with depth and benthic slope. The described behaviours for the Commerson's dolphin were: travelling, slow travelling, milling, resting, socializing, stationary swimming and diving. A new behavioural context was assigned to diving, a behaviour that showed a high frequency during downing tide, suggesting a benthic foraging strategy. Additionally, we found a strong influence of the tide on Commerson's dolphin behaviour. Habitat use models indicated that dolphins prefer shallow water inside the estuary. The knowledge of the behavioural patterns and the habitat use of these endemic species, in this unexplored area, provide tools for management and conservation purposes.

PKS 2005-489 at VHE: four years of monitoring with HESS and simultaneous multi-wavelength observations

Science.gov (United States)

H.E.S.S. Collaboration; Acero, F.; Aharonian, F.; Akhperjanian, A. G.; Anton, G.; Barres de Almeida, U.; Bazer-Bachi, A. R.; Becherini, Y.; Behera, B.; Benbow, W.; Bernlöhr, K.; Bochow, A.; Boisson, C.; Bolmont, J.; Borrel, V.; Brucker, J.; Brun, F.; Brun, P.; Bühler, R.; Bulik, T.; Büsching, I.; Boutelier, T.; Chadwick, P. M.; Charbonnier, A.; Chaves, R. C. G.; Cheesebrough, A.; Chounet, L.-M.; Clapson, A. C.; Coignet, G.; Costamante, L.; Dalton, M.; Daniel, M. K.; Davids, I. D.; Degrange, B.; Deil, C.; Dickinson, H. J.; Djannati-Ataï, A.; Domainko, W.; O'C. Drury, L.; Dubois, F.; Dubus, G.; Dyks, J.; Dyrda, M.; Egberts, K.; Eger, P.; Espigat, P.; Fallon, L.; Farnier, C.; Fegan, S.; Feinstein, F.; Fiasson, A.; Förster, A.; Fontaine, G.; Füßling, M.; Gabici, S.; Gallant, Y. A.; Gérard, L.; Gerbig, D.; Giebels, B.; Glicenstein, J. F.; Glück, B.; Goret, P.; Göring, D.; Hauser, M.; Heinz, S.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hinton, J. A.; Hoffmann, A.; Hofmann, W.; Hofverberg, P.; Holleran, M.; Hoppe, S.; Horns, D.; Jacholkowska, A.; de Jager, O. C.; Jahn, C.; Jung, I.; Katarzyński, K.; Katz, U.; Kaufmann, S.; Kerschhaggl, M.; Khangulyan, D.; Khélifi, B.; Keogh, D.; Klochkov, D.; Kluźniak, W.; Kneiske, T.; Komin, Nu.; Kosack, K.; Kossakowski, R.; Lamanna, G.; Lenain, J.-P.; Lohse, T.; Marandon, V.; Martineau-Huynh, O.; Marcowith, A.; Masbou, J.; Maurin, D.; McComb, T. J. L.; Medina, M. C.; Méhault, J.; Moderski, R.; Moulin, E.; Naumann-Godo, M.; de Naurois, M.; Nedbal, D.; Nekrassov, D.; Nicholas, B.; Niemiec, J.; Nolan, S. J.; Ohm, S.; Olive, J.-F.; de Oña Wilhelmi, E.; Orford, K. J.; Ostrowski, M.; Panter, M.; Paz Arribas, M.; Pedaletti, G.; Pelletier, G.; Petrucci, P.-O.; Pita, S.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raubenheimer, B. C.; Raue, M.; Rayner, S. M.; Renaud, M.; Rieger, F.; Ripken, J.; Rob, L.; Rosier-Lees, S.; Rowell, G.; Rudak, B.; Rulten, C. B.; Ruppel, J.; Sahakian, V.; Santangelo, A.; Schlickeiser, R.; Schöck, F. M.; Schwanke, U.; Schwarzburg, S.; Schwemmer, S.; Shalchi, A.; Sikora, M.; Skilton, J. L.; Sol, H.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stinzing, F.; Superina, G.; Szostek, A.; Tam, P. H.; Tavernet, J.-P.; Terrier, R.; Tibolla, O.; Tluczykont, M.; van Eldik, C.; Vasileiadis, G.; Venter, C.; Venter, L.; Vialle, J. P.; Vincent, P.; Vivier, M.; Völk, H. J.; Volpe, F.; Wagner, S. J.; Ward, M.; Zdziarski, A. A.; Zech, A.

2010-02-01

Aims: Our aim is to study the very high energy (VHE; E>100 GeV) γ-ray emission from BL Lac objects and the evolution in time of their broad-band spectral energy distribution (SED). Methods: VHE observations of the high-frequency peaked BL Lac object PKS 2005-489 were made with the High Energy Stereoscopic System (HESS) from 2004 through 2007. Three simultaneous multi-wavelength campaigns at lower energies were performed during the HESS data taking, consisting of several individual pointings with the XMM-Newton and RXTE satellites. Results: A strong VHE signal, ~17σ total, from PKS 2005-489 was detected during the four years of HESS observations (90.3 h live time). The integral flux above the average analysis threshold of 400 GeV is ~3% of the flux observed from the Crab Nebula and varies weakly on time scales from days to years. The average VHE spectrum measured from ~300 GeV to ~5 TeV is characterized by a power law with a photon index, Γ = 3.20± 0.16_stat± 0.10_syst. At X-ray energies the flux is observed to vary by more than an order of magnitude between 2004 and 2005. Strong changes in the X-ray spectrum (ΔΓX ≈ 0.7) are also observed, which appear to be mirrored in the VHE band. Conclusions: The SED of PKS 2005-489, constructed for the first time with contemporaneous data on both humps, shows significant evolution. The large flux variations in the X-ray band, coupled with weak or no variations in the VHE band and a similar spectral behavior, suggest the emergence of a new, separate, harder emission component in September 2005. Supported by CAPES Foundation, Ministry of Education of Brazil.Now at Harvard-Smithsonian Center for Astrophysics, Cambridge, USA.Now at W.W. Hansen Experimental Physics Laboratory & Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, Stanford, USA.

Glaciers in Patagonia: Controversy and prospects

Science.gov (United States)

Kargel, J. S.; Alho, P.; Buytaert, W.; Célleri, R.; Cogley, J. G.; Dussaillant, A.; Guido, Z.; Haeberli, W.; Harrison, S.; Leonard, G.; Maxwell, A.; Meier, C.; Poveda, G.; Reid, B.; Reynolds, J.; Rodríguez, C. A. Portocarrero; Romero, H.; Schneider, J.

2012-05-01

Lately, glaciers have been subjects of unceasing controversy. Current debate about planned hydroelectric facilities—a US7- to 10-billion megaproject—in a pristine glacierized area of Patagonia, Chile [Romero Toledo et al., 2009; Vince, 2010], has raised anew the matter of how glaciologists and global change experts can contribute their knowledge to civic debates on important issues. There has been greater respect for science in this controversy than in some previous debates over projects that pertain to glaciers, although valid economic motivations again could trump science and drive a solution to the energy supply problem before the associated safety and environmental problems are understood. The connection between glaciers and climate change—both anthropogenic and natural—is fundamental to glaciology and to glaciers' practical importance for water and hydropower resources, agriculture, tourism, mining, natural hazards, ecosystem conservation, and sea level [Buytaert et al., 2010; Glasser et al., 2011]. The conflict between conservation and development can be sharper in glacierized regions than almost anywhere else. Glaciers occur in spectacular natural landscapes, but they also supply prodigious exploitable meltwater.

Regionalización de los días secos en Argentina: Un enfoque metodológico Regionalization of dry days in Argentina: A methodological approach

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María L Bettolli

2010-12-01

Full Text Available La regionalización de diferentes variables climáticas ha sido llevada a cabo en diversas zonas del mundo, dado que para distintos propósitos es conveniente dividir espacialmente la climatología de una variable en un número de áreas cuasi-homogéneas. El objetivo de este trabajo es la obtención de una regionalización objetiva de las distintas variabilidades temporales de las cantidades de días secos en la República Argentina durante el trimestre de verano. Con el fin de lograr regiones con similar variabilidad temporal en las cantidades de días secos se exploraron dos métodos: Análisis de Componentes Principales (ACP y el algoritmo de agrupamiento no-jerárquico de k-means. En base a una evaluación de los patrones espaciales, la regionalización obtenida mediante el método de k-means aplicado sobre las componentes principales rotadas más importantes, es más apropiada en comparación con la determinada por el método de ACP rotadas. Mediante este método, el territorio nacional presenta seis regiones principales: las regiones Centro- Este; Noreste; Centro y Sur Bonaerense; Noroeste; Centro-Oeste y Patagónica, las cuales son climáticamente coherentes.Objective regionalizations of different climatic variables have been performed in many regions of the World. For different purposes is convenient to make a spatial regionalization to find quasi-homogeneous climatic regions. The main objective of this work is to identify spatially homogeneous regions of dry days in Argentina with different temporal variabilities during summer season. In order to achieve regions with similar temporal variability in the amount of dry days, two methods are explored: principal component analysis (PCA and k-means nonhierarchical cluster method. By means of a spatial patterns examination, the regionalization derived by k-means on the most important rotated principal components extracted is more adequate in comparison with the proposed by PCA method. Through

Respiratory function in voluntary participating Patagonia sea lions in sternal recumbency

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Andreas Fahlman

2016-11-01

Full Text Available We measured esophageal pressures (n=4, respiratory flow rates (n=5, and expired O2 and CO2 (n=4 in five adult Patagonia sea lions (Otaria flavescens, body mass range 94.3-286.0 kg during voluntary breaths while laying down. The data were used to estimate the dynamic specific lung compliance (sCL, cmH2O-1, the O2 consumption rate (VO2 and CO2 production rates (VCO2 during rest. Our results indicate that the resting tidal volume in Patagonia sea lions is approximately 47-73% of the estimated total lung capacity. The esophageal pressures indicated that expiration is passive during voluntary breaths. The average sCL of dolphins was 0.41±0.11 cmH2O−1, which is similar to those measured in anesthetized sea lions and awake cetaceans, and significantly higher as compared with humans (0.08 cmH2O−1. The average estimated and using breath-by-breath respirometry were 1.023 ± 0.327 L O2 min-1 (range: 0.695-1.514 L O2 min−1 and 0.777 ± 0.318 L CO2 min-1, (range: 0.510-1.235 L CO2 min-1, respectively, which is similar to previously published metabolic measurements from California and Steller sea lions using conventional flow-through respirometry. Our data provide end-tidal gas composition and provide novel data for respiratory physiology in pinnpeds, which may be important for clinical medicine and conservation efforts.

Lateglacial and Holocene climatic changes in south-eastern Patagonia inferred from carbonate isotope records of Laguna Potrok Aike (Argentina)

Science.gov (United States)

Oehlerich, M.; Mayr, C.; Gussone, N.; Hahn, A.; Hölzl, S.; Lücke, A.; Ohlendorf, C.; Rummel, S.; Teichert, B. M. A.; Zolitschka, B.

2015-04-01

First results of strontium, calcium, carbon and oxygen isotope analyses of bulk carbonates from a 106 m long sediment record of Laguna Potrok Aike, located in southern Patagonia are presented. Morphological and isotopic investigations of μm-sized carbonate crystals in the sediment reveal an endogenic origin for the entire Holocene. During this time period the calcium carbonate record of Laguna Potrok Aike turned out to be most likely ikaite-derived. As ikaite precipitation in nature has only been observed in a narrow temperature window between 0 and 7 °C, the respective carbonate oxygen isotope ratios serve as a proxy of hydrological variations rather than of palaeotemperatures. We suggest that oxygen isotope ratios are sensitive to changes of the lake water balance induced by intensity variations of the Southern Hemisphere Westerlies and discuss the role of this wind belt as a driver for climate change in southern South America. In combination with other proxy records the evolution of westerly wind intensities is reconstructed. Our data suggest that weak SHW prevailed during the Lateglacial and the early Holocene, interrupted by an interval with strengthened Westerlies between 13.4 and 11.3 ka cal BP. Wind strength increased at 9.2 ka cal BP and significantly intensified until 7.0 ka cal BP. Subsequently, the wind intensity diminished and stabilised to conditions similar to present day after a period of reduced evaporation during the "Little Ice Age". Strontium isotopes (87Sr/86Sr ratio) were identified as a potential lake-level indicator and point to a lowering from overflow conditions during the Glacial (∼17 ka cal BP) to lowest lake levels around 8 ka cal BP. Thereafter the strontium isotope curve resembles the lake-level curve which is stepwise rising until the "Little Ice Age". The variability of the Ca isotope composition of the sediment reflects changes in the Ca budget of the lake, indicating higher degrees of Ca utilisation during the period with

Paleoecología: el uso de los quironómidos fósiles (Diptera: Chironomidae en reconstrucciones paleoambientales durante el Cuaternario en la Patagonia

Directory of Open Access Journals (Sweden)

Julieta MASSAFERRO

2009-01-01

Full Text Available Entre los indicadores biológicos lacustres más utilizados en las reconstrucciones ambientales, se encuentran el polen, los ostrácodos y las diatomeas, y entre los insectos, los coleópteros y los quironómidos. Este grupo ha cobrado gran importancia en los últimos tiempos, debido a los resultados prometedores que se han obtenido en reconstrucciones climáticas realizadas en América del Norte y Europa. En América del Sur, el uso de los quironómidos fósiles en estudios cuaternarios es relativamente limitado, principalmente por su escaso conocimiento taxonómico regional. La mayor parte de estos estudios fueron realizados en lagos glaciares patagónicos de Argentina y Chile. Las larvas de quironómidos constituyen una valiosa herramienta paleolimnológica, por ser un grupo de organismos altamente sensible a cambios ambientales, tanto naturales como artificiales. Además, es un grupo de insectos ampliamente distribuido y con una abundancia y diversidad relativamente altas. Sus cápsulas cefálicas se preservan en los sedimentos lacustres y poseen caracteres importantes que permiten identificar géneros y muchas veces especies. El estudio de los ensambles de quironómidos en sedimentos lacustres puede ser utilizado con distintos objetivos, por ejemplo, para estudios de eutrofización, ya que responden rápidamente a cambios en la concentración de nutrientes, materia orgánica y otros elementos, como metales pesados. No obstante, uno de los potenciales más importantes de este grupo de insectos es su sensibilidad a los cambios de temperatura, por este motivo, la aplicación más importante de su estudio en sedimentos se centra en las reconstrucciones climáticas. Esta contribución es una síntesis de los resultados de los trabajos publicados en la Patagonia argentina y chilena, sobre la base del uso de los quironómidos fósiles en reconstrucciones paleoambientales.

Estado, sociedad civil y prácticas corporales en la construcción de la nacionalidad : San Carlos de Bariloche, 1920-1945

OpenAIRE

Lusetti, Liliana; Podlubne, Adriana; Sacarelo, Cristina

2009-01-01

Finalizada la campaña militar contra el indígena en la Patagonia, el Estado nacional incorporó los territorios del sur a la órbita nacional en la figura de los Territorios Nacionales, creados por ley en 1884. Estos territorios no tenían autonomía política y fueron concebidos por la dirigencia argentina como espacios donde era imperioso construir la nacionalidad argentina. Fue en las escuelas de los Territorios donde estos discursos tuvieron mayor impacto, debido a que la población chilena e i...

NuSTAR discovery of a young, energetic pulsar associated with the luminous gamma-ray source HESS J1640–465

Energy Technology Data Exchange (ETDEWEB)

Gotthelf, E. V.; Halpern, J. P.; Hailey, J. C. [Columbia Astrophysics Laboratory, Columbia University, 550 West 120th Street, New York, NY 10027-6601 (United States); Tomsick, J. A.; Boggs, S. E.; Craig, W. W. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Gelfand, J. D. [NYU Abu Dhabi, PO Box 129188, Abu Dhabi (United Arab Emirates); Harrison, F. A. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Christensen, F. E. [DTU Space-National Space Institute, Technical University of Denmark, Elektrovej 327, 2800 Lyngby (Denmark); Kaspi, V. M. [Department of Physics, McGill University, Montreal, QC H3A 2T8 (Canada); Stern, D. K. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Zhang, W. W., E-mail: eric@astro.columbia.edu [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2014-06-20

We report the discovery of a 206 ms pulsar associated with the TeV γ-ray source HESS J1640–465 using the Nuclear Spectroscopic Telescope Array (NuSTAR) X-ray observatory. PSR J1640–4631 lies within the shell-type supernova remnant (SNR) G338.3–0.0, and coincides with an X-ray point source and putative pulsar wind nebula (PWN) previously identified in XMM-Newton and Chandra images. It is spinning down rapidly with period derivative P-dot = 9.758(44) × 10{sup –13}, yielding a spin-down luminosity E-dot = 4.4 × 10{sup 36} erg s{sup –1}, characteristic age τ{sub c}≡P/2 P-dot = 3350 yr, and surface dipole magnetic field strength B{sub s} = 1.4 × 10{sup 13} G. For the measured distance of 12 kpc to G338.3–0.0, the 0.2-10 TeV luminosity of HESS J1640–465 is 6% of the pulsar's present E-dot . The Fermi source 1FHL J1640.5–4634 is marginally coincident with PSR J1640–4631, but we find no γ-ray pulsations in a search using five years of Fermi Large Area Telescope (LAT) data. The pulsar energetics support an evolutionary PWN model for the broadband spectrum of HESS J1640–465, provided that the pulsar's braking index is n ≈ 2, and that its initial spin period was P {sub 0} ∼ 15 ms.

Episodic Jurassic to Lower Cretaceous intraplate compression in Central Patagonia during Gondwana breakup

Science.gov (United States)

Navarrete, César; Gianni, Guido; Echaurren, Andrés; Kingler, Federico Lince; Folguera, Andrés

2016-12-01

From Lower Jurassic to Lower Cretaceous, several intraplate compression events affected discrete sectors of Central Patagonia, under a general context of crustal extension associated with Gondwana breakup. This was demonstrated by means of 2D and 3D seismic and borehole data, which show partial inversion of Lower and Middle Jurassic extensional structures of the Chubut and Cañadón Asfalto basins, during the earliest stages of breakup. A comparison with surrounding areas in Patagonia, where similar Jurassic intraplate compression was described, allowed the discrimination of three discrete pulses of subtle compression (C1: ∼188-185 Ma; C2: ∼170-163; C3: ∼157-136? Ma). Interestingly, episodic intraplate compressional events are closely followed by high flux magmatic events linked to the westward expansion of the Karoo-Ferrar thermal anomaly, which impacted on the lithosphere of southwest Gondwana in Lower Jurassic. In addition, we determined the approximate direction of the main compressive strain (σ1) compatible with other Jurassic intraplate belts of South America. These observations led us to propose a linkage between a thermo mechanically weakened continental crust due to LIPs activity, changes in plate motions and ridge-push forces generated by the opening of the Weddell Sea, in order to explain intraplate shortening, interrupted while Karoo LIPs magmatic invigoration took place.

Hallazgo de restos de la serpiente Dinilysia patagonica Smith-Woodward 1901 en una nueva localidad del Santoniano de Patagonia, Argentina

Directory of Open Access Journals (Sweden)

Triviño, L. N.

2015-12-01

Full Text Available In this study, we describe new remains of the cretaceous snake Dinilysia patagonica from beds of the locality Barreales Norte, Bajo de la Carpa Formation (Upper Santonian, Neuquén province, Argentina. The material comprises the back of a partially preserved skull, articulated with a fragment of the compound bone, atlas and axis. Additionally, six fragments of precloacal vertebrae have been preserved. The assignation to Dinilysia patagonica is based on: large skull, otooccipital with long paraoccipital process adjacent to an elongate supratemporal that extends farther the level of the occipital condyle; well developed sagital crest of parietal bone, continuously joined with the supraoccipital crest; italics I-like prootic; wide, short and robust vertebrae; prezygapophyses long and highly inclined above the horizontal; triangular section of vertebral centrum; reduced prezygapophyseal process; flattened neural arches with straight posterior edge. This material adds a new Upper Cretaceous location for the distribution of the species at the north of the Neuquén River.En este trabajo se describen nuevos restos de la serpiente cretácica Dinilysia patagonica recuperados en la localidad Barreales Norte, Formación Bajo de la Carpa (Santoniano superior, provincia del Neuquén, Argentina. El material comprende la parte posterior de un cráneo parcialmente conservado y articulado con un fragmento del hueso compuesto, atlas y axis. Además, se preservaron seis secciones de columna vertebral con vértebras precloacales. La asignación a Dinilysia patagonica se basa en: cráneo de tamaño grande, otooccipital con largo proceso paraoccipital adosado a un elongado supratemporal que se extiende más allá del nivel del cóndilo occipital; cresta sagital del parietal bien desarrollada y continua con la cresta del supraoccipital; proótico en forma de I cursiva; vértebras anchas, cortas y robustas; prezigapófisis largas y muy inclinadas sobre la horizontal

Argentina: Background and U.S. Relations

Science.gov (United States)

2008-11-05

Comercio Internacional, Y Culto, Comunicado de la Cancillería Argentina, September 11, 2008. 43 A. Rebossio, "Fernández Acusa al FBI de Desestablizar...Argentina," El País (Madrid), September 13, 2008. 44 “Argentina Slams Witness in Cash Suitcase Scandal,” Associated Press Newswires, November 4, 2008

Rainforest conifers of Eocene Patagonia: attached cones and foliage of the extant Southeast Asian and Australasian genus Dacrycarpus (Podocarpaceae).

Science.gov (United States)

Wilf, Peter

2012-03-01

Eocene caldera-lake beds at Laguna del Hunco (LH, ca. 52.2 Ma) and Río Pichileufú (RP, ca. 47.7 Ma) in Argentine Patagonia provide copious information about the biological history of Gondwana. Several plant genera from these sites are known as fossils from southern Australia and New Zealand and survive only in Australasian rainforests. The potential presence of Dacrycarpus (Podocarpaceae) holds considerable interest due to its extensive foliage-fossil record in Gondwana, its remarkably broad modern distribution in Southeast Asian and Australasian rainforests, its high physiological moisture requirements, and its bird-dispersed seeds. However, the unique seed cones that firmly diagnose Dacrycarpus were not previously known from the fossil record. I describe and interpret fertile (LH) and vegetative (LH and RP) material of Dacrycarpus and present a nomenclatural revision for fossil Dacrycarpus from South America. Dacrycarpus puertae sp. nov. is the first fossil occurrence of the unusual seed cones that typify living Dacrycarpus, attached to characteristic foliage, and of attached Dacrycarpus pollen cones and foliage. Dacrycarpus puertae is indistinguishable from living D. imbricatus (montane, Burma to Fiji). Dacrycarpus chilensis (Engelhardt) comb. nov. is proposed for Eocene vegetative material from Chile. Modern-aspect Dacrycarpus was present in Eocene Patagonia, demonstrating an astonishingly wide-ranging paleogeographic history and implying a long evolutionary association with bird dispersers. Dacrycarpus puertae provides the first significant Asian link for Eocene Patagonian floras, strengthens the biogeographic connections from Patagonia to Australasia across Antarctica during the warm Eocene, and indicates high-rainfall paleoenvironments.

An archaeological predictive model for locating rock shelter sites in Hesse Germany) that contain both Final Palaeolithic archaeology and Laacher See tephra

DEFF Research Database (Denmark)

Sauer, Florian Rudolf; Hoggard, Christian Steven; Zernack, Anke Verena

of foragers and the Late Glacial environment there. In contrast, in the medial zone in Hesse only a small number of surface scatters of lithic artefacts are known. No Late Glacial sites, particularly not rock shelter and cave locations, have been excavated in this region. Yet, it is precisely such locations...... of human impacts following the eruption, a dataset of c. 800 rock shelter locations throughout the state of Hesse was used to generate an archaeological predictive model (APM). The database was compiled in the early 1990 for the purpose of discovering new and well-stratified sites (Hofbauer, 1995......). In the project presented here, a landscape-archaeological approach in GIS was employed to estimate the correspondence of the local topography of rock shelter features with the topographic and cultural framework of known Late Palaeolithic sites. Typical parameters like rock shelter orientation and distance...

Operating practical experience at Argentina; Experiencia practica operativa en la Argentina

Energy Technology Data Exchange (ETDEWEB)

Quihillalt, Oscar [Nucleoelectria Argentina S.A., Buenos Aires (Argentina)

1998-12-31

Operating experiences of Atucha-1 and Embalse Nuclear Power Plants were discussed in this work. The technical and economic aspects, such as reliability, availability, personnel training, operating costs, prices and market, which exercise influence upon Argentina nuclear energy policy, mainly on the power electric generation by nuclear power plants were considered. Finally the current status of the nucleoelectric sector in Argentina and forecasting were analysed. 3 figs., 5 tabs.

NuSTAR discovery of a young, energetic pulsar associated with the luminous gamma-ray source Hess J1640-465

DEFF Research Database (Denmark)

Gotthelf, E. V.; Tomsick, J. A.; Halpern, J. P.

2014-01-01

We report the discovery of a 206 ms pulsar associated with the TeV γ-ray source HESS J1640-465 using the Nuclear Spectroscopic Telescope Array (NuSTAR) X-ray observatory. PSR J1640-4631 lies within the shell-type supernova remnant (SNR) G338.3-0.0, and coincides with an X-ray point source...... and putative pulsar wind nebula (PWN) previously identified in XMM-Newton and Chandra images. It is spinning down rapidly with period derivative 9.758(44) × 10-13, yielding a spin-down luminosity 4.4 × 1036 erg s-1, characteristic age 3350 yr, and surface dipole magnetic field strength Bs = 1.4 × 1013 G....... For the measured distance of 12 kpc to G338.3-0.0, the 0.2-10 TeV luminosity of HESS J1640-465 is 6% of the pulsar's present . The Fermi source 1FHL J1640.5-4634 is marginally coincident with PSR J1640-4631, but we find no γ-ray pulsations in a search using five years of Fermi Large Area Telescope (LAT) data...

Ikaite precipitation in a lacustrine environment - implications for palaeoclimatic studies using carbonates from Laguna Potrok Aike (Patagonia, Argentina)

Science.gov (United States)

Oehlerich, Markus; Mayr, Christoph; Griesshaber, Erika; Lücke, Andreas; Oeckler, Oliver M.; Ohlendorf, Christian; Schmahl, Wolfgang W.; Zolitschka, Bernd

2013-07-01

The monoclinic mineral ikaite (CaCO3 · 6H2O) and its pseudomorphs are potentially important archives for palaeoenvironmental reconstructions. Natural ikaite occurs in a small temperature range near freezing point and is reported mainly from marine and only rarely from continental aquatic environments. Ikaite transforms to more stable anhydrous forms of CaCO3 after an increase in temperature or when exposed to atmospheric conditions. The knowledge about conditions for natural ikaite formation, its stable isotope fractionation factors and isotopic changes during transformation to calcite is very restricted. Here, for the first time, primary precipitation of idiomorphic ikaite and its calcite pseudomorphs are reported from a subsaline lake, Laguna Potrok Aike, in southern Argentina. The calculated stable oxygen isotope fractionation factor between lake water and ikaite-derived calcite (αPAI = 1.0324 at a temperature of 4.1 °C) is close to but differs from that of primarily inorganically precipitated calcite. Pseudomorphs after ikaite rapidly disintegrate into calcite powder that is indistinguishable from μm-sized calcite crystals in the sediment record of Laguna Potrok Aike suggesting an ikaite origin of sedimentary calcites. Therefore, the Holocene carbonates of Laguna Potrok Aike have the potential to serve as a recorder of past hydrological variation.

Treating residual water according to the demands of its ulterior use: case of Neuquen river, Patagonia, Argentina; Optimizacion de requisitos de tratamiento de aguas residuales basado en la calidad del agua de acuerdo con el uso del cuerpo receptor: caso rio Neuquen, Patagonia, Argentina

Energy Technology Data Exchange (ETDEWEB)

Polla, Gabriela Maria; Dufilho, Ana Cecilia; Horne, Federico [Universidad Nacional del Comahue (Argentina)

2006-07-15

A developed methodology allows making a regional pacification based on the river's water quality and their guide levels for different uses. To get this methodology it was used an optimization model that allows obtaining the best combination of town and industrial liquid treatments of the region, which can make cheaper their construction and maintenance costs. The established regional stages of economical development, were simulated with the QUAL2E model, from this model was obtained the restriction coefficients of the optimization model. More over, this model allowed to prognosticate the behavior of the principal water quality components (dissolved and biochemical demand of oxygen, nitrogen, phosphorus and others) for different proposed stages. This methodology was applied over a section of Neuquen River (Argentina) which receives urban, industrial and farming effluents of three cities Centenario (Plant 1), Cinco Saltos (Plant 2) and Parque Industrial (Plant 3). From results, it can be affirmed that under present situation, there is not contamination hazard. However, under future scenarios, advanced and secondary treatment is required to assure meeting the quality standards, particularly when river discharge approach it annual minimum. [Spanish] Se desarrollo una metodologia que permite hacer una planificacion regional basada en la calidad de agua del rio y sus niveles guias para distintos usos. Para ello se utilizo un modelo de optimizacion que permite obtener la mejor combinacion de tratamientos de liquidos municipales e industriales de la region que minimicen sus costos de construccion y mantenimiento. Los escenarios de desarrollo economico regional planteados se simularon con el modelo QUAL2E, de donde se obtuvieron los coeficientes de las restricciones del modelo de optimizacion. El modelo de simulacion permitio, ademas, pronosticar el comportamiento de los principales componentes de calidad del agua (oxigeno disuelto, demanda bioquimica de oxigeno

Epidemiological investigations into multiple sclerosis in southern Hesse. II. The distribution of cases in relation to exogenous features.

Science.gov (United States)

Lauer, K; Firnhaber, W

1984-10-01

In order to discover possible exogenous variables associated with a higher multiple sclerosis risk, the distribution of cases with definite and probable multiple sclerosis ascertained in the course of a micro-epidemiologic study in Southern Hesse was evaluated and compared with some environmental factors. The prevalence in 1980, the prevalence of cases with disease-onset within the region according to locality of onset and the rate of native Southern Hesse patients according to childhood residence all showed a similar geographical distribution, with the highest values in the south-eastern, mountainous part of the region. This district has a lower annual mean temperature, more annual snow-days and a higher annual precipitation compared to the remaining area. A statistical comparison revealed no association with industrial or agricultural activities, with a particular type of land use, with cattle, pig- or horse-breeding, or with sanitary or housing standards. On the other hand, a slight association with the soil type could be demonstrated, with higher rates on loam and clay subsoils when compared to predominantly sandy regions. Whether this finding has any significance or not remains to be clarified.

Biología reproductiva, crecimiento y dieta del caracol ciego Buccinanops cochlidium (Dillwyn, 1817) (Gastropoda: Nassariidae) en el golfo San José, Patagonia Argentina

OpenAIRE

Averbuj, Andrés

2009-01-01

El genero Buccinanops (dŽOrbigny, 1841) (Caenogastropoda, Nassariidae) es endémico del océano Atlántico sudoccidental, y su nombre significa "sin ojos", debido a su ausencia en los adultos. El caracol Buccinanops cochlidium (Dillwyn, 1817) se distribuye en aguas someras de las costas desde el paralelo 19ºS (Brasil) hasta el golfo San Matias (43º44ŽS) en Argentina, a profundidades entre 5 y 50m. En el golfo San José habita aguas someras en fondos de sedimento fino. Se realizo un estudio de la ...

Medical revolution in Argentina.

Science.gov (United States)

Ballarin, V L; Isoardi, R A

2010-01-01

The paper discusses the major Argentineans contributors, medical physicists and scientists, in medical imaging and the development of medical imaging in Argentina. The following are presented: history of medical imaging in Argentina: the pioneers; medical imaging and medical revolution; nuclear medicine imaging; ultrasound imaging; and mathematics, physics, and electronics in medical image research: a multidisciplinary endeavor.

POTENCIAL TURÍSTICO DE MOQUEHUE, PATAGONIA ARGENTINA

Directory of Open Access Journals (Sweden)

Martín Capel

2016-12-01

Full Text Available El lago Moquehue es un espejo de agua ubicado en el departamento Aluminé, provincia del Neuquén, en plena cordillera de los Andes. Se encuentra a 148 km de la localidad de Zapala por ruta provincial No 13 y a 230 km por ruta provincial No 23. El área mencionada se encuentra a casi 400 Km de Neuquén Capital, enclavado a 1.200 msnm. (Figura 1. El topónimo de su nombre, ciertamente desconocido, referiría a un posible origen en Mongueln-Hue (Lugar donde se da vida o Neque–Hue (Sitio de Lechuzas o de Pesadillas (Erize, 1990.

Conflictos ecoterritoriales transfronterizos y megaproyectos extractivistas en cuencas compartidas de la Patagonia; Conflitos ecoterritoriais transfronteiriços e megaprojetos extrativistas nas bacias da Patagônia; Cross-border Eco-territorial Conflicts and Extractivist Megaprojects in the Patagonia River Basins

Directory of Open Access Journals (Sweden)

Bárbara Jerez Henríquez

2015-01-01

Full Text Available Resumen: Las cuencas transfronterizas de la Patagonia Andina argentino- chilena en los útimos 15 años se ha convertido en un espacio transnacional en el que aterrizan megaproyectos de minería y represas hidroeléctricas que conllevan importantes impactos en los ecosistemas, economías y culturas locales, como parte de una tendencia en América Latina orientada al avance de las territorialidades extractivistas hacia zonas fronterizas que además significa transgredir marcos legales previos para el manejo de cuencas compartidas. En ese contexto emergen fuertes procesos de resistencia desde diversas narrativas que en su conjunto reivindican otras territorialidades en estas cuencas abarcando escalas locales y transfronterizas que plantean nuevos debates y desafíos para discutir los conflictos ecoterritoriales que emergen en zonas de fronteras.     Palabras clave: extractivismo, cuencas, fronteras, territorialidades, Patagonia.       Resumo: As bacias transfronteiriças da Patagônia Andina Argentino-chilena nos últimos 15 anos se converteram em um espaço transnacional em que aterrissam mega-projetos de mineração e represas hidroelétricas que conduzem importantes impactos nos ecossistemas, economias e culturas locais, como parte de uma tendência na América Latina de avanço das territorialidades extrativistas em direção a zonas fronteiriças que, além de tudo, significam transgredir marcos legais para o manejo de bacias divididas. Nesse       contextos emergem fortes processos de resistência desde diversas narrativas que em seu conjunto reivindicam outras territorialidades nestas bacias cobrindo escalas locais e transfronteiriças que colocam novos debates e desafios para se discutir os conflitos ecoterritoriais que emergem nas zonas de fronteira.     Palavras-chave: extrativismo, bacias, fronteiras, territorialidade, Patagônia.       Abstract: The cross-border river basins of the Argentine-Chilean Andean Patagonia have

Liolaemus lizards (Squamata: Liolaemidae) as hosts for the nymph of Amblyomma parvitarsum (Acari: Ixodidae), with notes on Rickettsia infection.

Science.gov (United States)

Muñoz-Leal, Sebastián; Tarragona, Evelina L; Martins, Thiago F; Martín, Claudia M; Burgos-Gallardo, Freddy; Nava, Santiago; Labruna, Marcelo B; González-Acuña, Daniel

2016-10-01

Adults of Amblyomma parvitarsum are common ectoparasites of South American camelids of the genera Lama and Vicugna, occuring in highlands of Argentina, Bolivia, Chile, Peru and also in Argentinean Patagonia. Whereas larval stages of this tick are known to feed on small lizards, host records for the nymphal instar have remained unreported. Supported by morphological and molecular analyses, herein we report A. parvitarsum nymphs parasitizing two Liolaemus species (Reptilia: Squamata) in the Andean Plateau of Argentina and Chile. Additionally, by a PCR screening targetting gltA and ompA genes, DNA of Rickettsia was detected in one of the collected nymphs. Obtained sequences of this agent were identical to a recent Rickettsia sp. described infecting adults of this tick species in Chile and Argentina.

De Patagonia a Budapest: caminos europeos de fósiles santacrucenses (1845-1956)

OpenAIRE

Vizcaíno, Sergio Fabián; Bargo, M. Susana

2013-01-01

A fines del siglo XIX y principios del XX, acicateados por los descubrimientos de los hermanos Ameghino, los paleontólogos evolucionistas de América del Norte y Europa posaron sus ojos en los mamíferos fósiles de Patagonia. Mientras los primeros organizaron expediciones, los europeos se valieron mayormente de otras formas comunes en la época para hacer colecciones de historia natural, como el intercambio y la compra. En el viejo continente, el devenir de los fósiles patagónicos no escapó a la...

TAFONOMÍA DE RESTOS ÓSEOS PROVENIENTES DE EGAGRÓPILAS DE CORAGYPS ATRATUS (JOTE DE CABEZA NEGRA EN EL NOROESTE DE LA PATAGONIA ARGENTINA/Taphonomy of bones remains from pellets of Coragyps Atratus (black vulture in the northwest of the argentinian Patag

Directory of Open Access Journals (Sweden)

Fernando Ballejo

2012-11-01

Full Text Available Existen diversos estudios actualísticos en tafonomía sobre restos de presas de diferentes especies de aves raptoras. Sin embargo, este tipo de trabajos en aves carroñeras ha sido escasamente considerado hasta el momento en Argentina, a pesar que ellas cumplen un papel fundamental en la alteración y transporte de cadáveres. Coragyps atratus (jote de cabeza negra tiene la particularidad de formar posaderos comunales cercanos a áreas de actividades humanas y de alimentarse de animales de todos los tamaños, por lo que pueden interferir en la formación de sitios arqueológicos. El objetivo de este trabajo es realizar un análisis tafonómico sobre los restos óseos recuperados de egagrópilas de C. atratus en el Noroeste patagónico, con el fin de generar herramientas que permitan identificar a estas aves como posibles agentes acumuladores. Se recolectaron 469 egagrópilas distribuidas en tres posaderos del Noroeste patagónico. Se identificaron los elementos recuperados y se evaluaron los grados de alteraciones por ácidos gástricos. Lepus europaeus y Ovis aries dominaron las muestras. Los elementos más representativos pertenecen al autopodio, principalmente falanges. Todos ellos muestran signos de digestión, que van desde porosidades superficiales, perforaciones y fracturas, con la desaparición de la médula en el caso de varias falanges; denotando diferencias en relación al tamaño de la presa consumida. Abstract There are several actualistic taphonomic studies regarding different species of birds of prey. However, the studies focus on scavenger birds have been scarcely considered in Argentina, despite the fact that they play a fundamental role in the alteration and transportation of carcasses. A peculiar characteristic of Coragyps atratus (black vulture is that it builds communal roosts near places where human activities are developed and it feeds on animals of varying size, which may interfere with the formation of archaeological

Contabilidad y profesión: la evolución de la profesión de contador público y de las instituciones de enseñanza de la contabilidad en la República Argentina (1794-1960. Particularidades de la región patagónica

Directory of Open Access Journals (Sweden)

Walter Carrizo

2016-08-01

Full Text Available La profesión de Contador Público en Argentina ha sufrido grandes transformaciones. Desde los últimos años del siglo XVIII, cuando se advirtió que quienes fueran a desempeñarse en la administración pública o en el comercio debían tener instrucción contable, pasando por las simples prácticas contables que se acreditaban mediante exámenes específicos durante el siglo XIX, hasta la regulación del título habilitante que permitía su ejercicio, a mediados del siglo XX. Esta evolución va de la mano con los cambios económicos experimentados por el país a partir de la década de 1860 y que posibilitó la aparición de instituciones dedicadas a la enseñanza dela contabilidad. Esevidente por cierto, que para entender la evolución de la profesión contable es necesario revisar también cuál ha sido el devenir de la enseñanza de la contabilidad. Si bien internacionalmente se cuenta con material que atestigua el desarrollo de las instituciones dedicadas a la enseñanza de la contabilidad, es reconocido por los propios historiadores en Argentina, un vacío en este tema, más aún en el nivel universitario. Ha sido también escaso  el material encontrado sobre la evolución de la profesión, a pesar de tener una fuerte regulación y presencia en la sociedad argentina. Es así que a través de este  trabajo se buscar comprender cuál ha sido la evolución de la profesión contable y de los estudios de la contabilidad en Argentina entre fines del siglo XVIII y mediados del siglo XX, un período que si bien puede parecer extenso, se considera pertinente su estudio, a raíz de las lagunas investigativas observadas. Se realiza un apartado especial a las consideraciones de la profesión en la Patagonia argentina y en especial en la ciudad de Comodoro Rivadavia[1], dadas sus características de aislamiento y tardío afianzamiento poblacional.   Para la realización de este escrito, se ha recurrido a la revisión bibliográfica del material

Argentina's nuclear red herring

International Nuclear Information System (INIS)

Perera, J.

1983-01-01

The article deals with Argentina's nuclear power programme over the last 30 years, including the country's efforts to be nuclear independent of the United States, as well as its aspirations to be a nuclear supplier to latin America. The latter policy on economic, rather than military grounds for nuclear weapons, has led to Argentina's decision to build a uranian enrichment plant. (U.K.)

History of radiobiology in Argentina

International Nuclear Information System (INIS)

Mayo, Jose

2004-01-01

Radiobiology is a multidisciplinary science dealing with ionising radiation effects on biological material. The history of Radiobiology begins in Germany and France around 1886. Radiobiology was introduced in Argentina in 1926 at the Institute of Oncology Angel H. Roffo as a biomedical research branch. Later on in 1957 was incorporated at the National Atomic Energy Commission (CNEA) of Argentina as a result of the newly started nuclear activities in Argentina. Prior that time no Radiobiology research existed in Argentina. To fill this need a Project to create new laboratories was elaborated by the CNEA. New laboratories in Radiobiodosimetry, Cellular Radiobiology, Radiopathology, Radiomicrobiology, Genetics and Somatic Effects were created. Human resources on different areas of Radiobiology were formed with the assistance of IAEA. With professional and technical personnel specialized in Radiobiology at the beginning of the 1970 decade, the transference of fundamental and applied research to others laboratories started. (author)

A 17-year Record of Meteorological Observations Across the Gran Campo Nevado Ice Cap in Southern Patagonia, Chile, Related to Synoptic Weather Types and Climate Modes

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Stephanie S. Weidemann

2018-05-01

Full Text Available The network of long-term meteorological observations in Southernmost Patagonia is still sparse but crucial to improve our understanding of climatic variability, in particular in the more elevated and partially glaciated Southernmost Andes. Here we present a unique 17-year meteorological record (2000–2016 of four automatic weather stations (AWS across the Gran Campo Nevado Ice Cap (53°S in the Southernmost Andes (Chile and the conventional weather station Jorge Schythe of the Instituto de la Patagonia in Punta Arenas for comparison. We revisit the relationship between in situ observations and large-scale climate models as well as mesoscale weather patterns. For this purpose, a 37-year record of ERA Interim Reanalysis data has been used to compute a weather type classification based on a hierarchical correlation-based leader algorithm. The orographic perturbation on the predominantly westerly airflow determines the hydroclimatic response across the mountain range, leading to significant west-east gradients of precipitation, air temperature and humidity. Annual precipitation sums heavily drop within only tens of kilometers from ~7,500 mm a−1 to less than 800 mm a−1. The occurrence of high precipitation events of up to 620 mm in 5 days and wet spells of up to 61 consecutive days underscore the year-around wet conditions in the Southernmost Andes. Given the strong link between large-scale circulation and orographically controlled precipitation, the synoptic-scale weather conditions largely determine the precipitation and temperature variability on all time scales. Major synoptic weather types with distinct low-pressure cells in the Weddell Sea or Bellingshausen Sea, causing a prevailing southwesterly, northwesterly or westerly airflow, determine the weather conditions in Southernmost Patagonia during 68% of the year. At Gran Campo Nevado, more than 80% of extreme precipitation events occur during the persistence of these weather types. The

Chronological study of the pre-jurassic basement rocks of southern Patagonia

International Nuclear Information System (INIS)

Pankhurst, R.J; Rapela, C.W; Loske, W.P; Fanning, C.M

2001-01-01

Southern Patagonia east of the Andes was the site of extensive rhyolite volcanism during the Jurassic rifting of Gondwana and subsequent shallow marine basin formation during the Cretaceous. Thus exposures of pre-Jurassic basement are extremely sparse. Nevertheless, extraction of the maximum amount of information from these scattered outcrops of granite and metamorphic rocks is crucial to assessment of the Palaeozoic and earliest Mesozoic history and crustal structure of the Pacific margin of the supercontinent. In particular, the identification and possible correlation of early terrane accretion on this margin depends on comparison of pre-Jurassic igneous and metamorphic events with adjacent areas. This is a preliminary report on work now in progress to this end (au)

Crisis de la prensa Argentina

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Federico Rey Lennon

2015-01-01

Full Text Available La magnitud de la crisis económica Argentina es enorme y difícil saber hasta cuando se extenderá, agravada por una situación política frágil. La actual recesión ha hecho caer la inversión publicitaria a los niveles más bajos de los últimos años. De 1997 al 2001 la circulación de la prensa Argentina cayó en el 36 por ciento. El riesgo en Argentina es la eventual extranjerización de casi todos los medios de comunicación.

Paleontology, sedimentology and paleoenvironment of a new fossiliferous locality of the Jurassic Cañadón Asfalto Formation, Chubut Province, Argentina

Science.gov (United States)

Gallego, Oscar F.; Cabaleri, Nora G.; Armella, Claudia; Volkheimer, Wolfgang; Ballent, Sara C.; Martínez, Sergio; Monferran, Mateo D.; Silva Nieto, Diego G.; Páez, Manuel A.

2011-02-01

A new Late Jurassic assemblage of “conchostracans”, ostracods, bivalves and caddisfly cases from the locality “Estancia La Sin Rumbo”, Chubut Province (Patagonia, Argentina) is recorded. The fossils occur in the upper part of an outcropping 45 m thick volcaniclastic lacustrine sequence of yellowish tuffs and tuffites of the Puesto Almada Member, which is the upper member of the Cañadón Asfalto Formation with U/Pb age of 161 ± 3 Ma. The sequence represents one sedimentary cycle composed of a (lower) hemicycle of expansion and a (higher) hemicycle of contraction of the water body. The invertebrates lived in small freshwater bodies during the periods of expansion of the lake. The occurrence of a great number of small spinicaudatans, associated with mud-cracks, is evidence of dry climatic conditions and suggests several local mortality events. The spinicaudatan record of the fushunograptid-orthestheriid (component of the Eosestheriopsis dianzhongensis fauna) and the presence of Congestheriella rauhuti Gallego and Shen, suggest a Late Jurassic (Oxfordian to Tithonian) age. Caddisfly cases are recorded for the first time in the Cañadón Asfalto Basin.

Coccocypselum pulchellum (Rubiaceae, nuevo registro para Argentina

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Elsa L. Cabral

2007-01-01

Full Text Available Se cita Coccocypselum pulchellum por primera vez para Argentina, en Predio Guaraní, Misiones. Esta es la tercera especie de Coccocypselum registrada para la flora de Argentina junto con C. hasslerianum y C. lanceolatum. Se incluyen descripciones, ilustraciones y una clave para reconocer las tres especies argentinas de Coccocypselum.

Charcoal kiln sites, associated landscape attributes and historic forest conditions: DTM-based investigations in Hesse (Germany

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Marcus Schmidt

2016-03-01

Full Text Available Background An examination of the distribution of ancient charcoal kiln sites in the forest landscape seems to be worthwhile, since general trends in the selection of suitable kiln site locations in the past might become obvious. In this way forest landscape elements with a more intense usage by charcoal burning can be identified. By doing this, we can expect to gain information on the former condition and tree species composition of woodland. Investigations on the spatial distribution of charcoal kiln sites in relation to landscape attributes are sparse, however, probably due to the high on-site mapping effort. The outstanding suitability of LiDAR-derived digital terrain models (DTMs for the detection of charcoal kiln sites has been recently proved. Hence, DTM-based surveys of charcoal kiln sites represent a promising attempt to fill this research gap. Methods Based on DTM-based surveys, we analyzed the spatial distribution of charcoal kiln sites in two forest landscapes in the German federal state of Hesse: Reinhardswald and Kellerwald-Edersee National Park. In doing so, we considered the landscape attibutes "tree species composition", “water supply status”, “nutrient supply status”, “soil complex classes”, “altitude”, “exposition”, and “inclination”. Results We found that charcoal kiln sites were established preferably on hillside locations that provided optimal growing and regeneration conditions for European beech (Fagus sylvatica due to their acidic brown soils and sufficient water supply. These results are in line with instructions for the selection of appropriate kiln site locations, found in literature from the 18th to the 19th century. Conclusions We conclude that there were well-stocked, beech-dominated deciduous forest stands in northern Hesse before 1800, particularly at poorly accessible hillside locations. These large stocks of beech wood were utilized by the governments of the different Hessian territories

Saccharomyces eubayanus and Saccharomyces uvarum associated with the fermentation of Araucaria araucana seeds in Patagonia.

Science.gov (United States)

Rodríguez, M Eugenia; Pérez-Través, Laura; Sangorrín, Marcela P; Barrio, Eladio; Lopes, Christian A

2014-09-01

Mudai is a traditional fermented beverage, made from the seeds of the Araucaria araucana tree by Mapuche communities. The main goal of the present study was to identify and characterize the yeast microbiota responsible of Mudai fermentation as well as from A. araucana seeds and bark from different locations in Northern Patagonia. Only Hanseniaspora uvarum and a commercial bakery strain of Saccharomyces cerevisiae were isolated from Mudai and all Saccharomyces isolates recovered from A. araucana seed and bark samples belonged to the cryotolerant species Saccharomyces eubayanus and Saccharomyces uvarum. These two species were already reported in Nothofagus trees from Patagonia; however, this is the first time that they were isolated from A. araucana, which extends their ecological distribution. The presence of these species in A. araucana seeds and bark samples, led us to postulate a potential role for them as the original yeasts responsible for the elaboration of Mudai before the introduction of commercial S. cerevisiae cultures. The molecular and genetic characterization of the S. uvarum and S. eubayanus isolates and their comparison with European S. uvarum strains and S. eubayanus hybrids (S. bayanus and S. pastorianus), allowed their ecology and evolution us to be examined. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Nuclear Activities in Argentina, 2010

International Nuclear Information System (INIS)

Ferreri, J.C.; Ferreri, J.C.; Clausse, A.; Clausse, A.; Clausse, A.; Ordonez, J.P.; Mazzantini, O.A.

2011-01-01

Nuclear activities in Argentina are restarted. After almost two decades of near stagnation, the governments political decision of August 2006 regarding electrical energy production, considered the nuclear option as a valid one to solve the problems of the growing demand of electrical energy. This decision triggered again the activities related to the finalization of the third nuclear power reactor (Atucha-II), now actively progressing, the construction of a prototype of the CAREM integral advanced reactor, the life extension of the Embalse CANDU nuclear power plant (NPP) and the studies for the emplacement of a fourth NPP in an appropriate site. In all those years of near stagnation, there were notable exceptions related to the design and construction of experimental and radioisotope production reactors, led by INVAP, a state-owned industry, which exported its production. The accompanying industries of nuclear fuel elements production also remained active, given the demand of the two active NPPs. Meanwhile, the National Atomic Energy Commission of Argentina continued the efforts on research and development that were at the base of the technological achievements of the nuclear activities in Argentina. Nuclear safety studies associated with Atucha II and Embalse NPPs and radiological safety were also a substantive part of the continued efforts by Nucleo-Electrica de Argentina SA and the Nuclear Regulatory Authority of Argentina

Argentina [Country report

International Nuclear Information System (INIS)

Ferreyra, R.

2005-01-01

The airborne geophysical surveys developed in Argentina are described. They have got more than 500.000 km 2 acquiring data for U, Th, K and total background activity. Other types of published data are also mentioned (satellite imagery, seismic hazard, climate, soil distributions, etc.). The availability of maps with the abundances of elements analyzed at the country and also at laboratories from Canada is described, as well as data of analysis of several elements at two study areas proposed at the outset of the project. The availability of process rate data and epidemiological data is also explained. Argentina intended fully to participate in the CRP at the outset of the project. Due, however, to external resource constraints imposed on the participating organization (Comision Nacional de Energia Atomica, CNEA), the level of participation had to be significantly reduced. Nonetheless, in the first period of the CRP, Argentina undertook to collate existing geological and geochemical information within the country, and began to define potential areas for site specific natural systems safety indicator studies. (author)

La familia Cyatheaceae (Pteridophyta en Argentina The family Cyatheaceae (Pteridophyta in Argentina

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Gonzalo J Marquez

2010-06-01

Full Text Available La familia Cyatheaceae comprende alrededor de 500 especies de helechos arborescentes. Su distribución es pantropical y en Argentina se encuentra representada por 4 especies, reunidas en los géneros Alsophila y Cyathea: A. setosa, A. odonelliana, C. atrovirens y C. delgadii. En este trabajo se presenta una actualización de la información disponible hasta el momento referente a estas especies. Se exponen microfotografías de las esporas, que presentan la superficie con lomos en Alsophila y con cordones en Cyathea. Se ilustran los indusios y escamas de la base de los pecíolos, que son de importancia fundamental para la diferenciación de las especies estudiadas. Asimismo se presenta un mapa de distribución y una clave de las especies que crecen en Argentina.The family Cyatheaceae comprises about 500 species of tree ferns. Their distribution is pantropical and in Argentina is represented by four species, grouped in genera Alsophila y Cyathea: A. setosa, A. odonelliana, C. atrovirens and C. delgadii. In this paper, an update of the available information of the mentioned species is presented. A key to diferentiate the species growing in Argentina, their descriptions and a distribution map are also given. Spores are ridged in Alsophila and with rodlets in Cyathea. Indusia and scales of petiole basis are also illustrated.

La proyección colonial de Chile a la Patagonia Insular en el siglo XVIII

OpenAIRE

Urbina Carrasco, María Ximena

2011-01-01

In this article, the geopolitical consequences of the shipwreck of the English frigate Wager and the landfall of the ship Anna into the coasts of the Western Insular Patagonia in 1741 are presented, which were part of the fleet of George Anson. The news reporting the English presence in the deserted and unknown insular and coastal territory southernmost Chiloé, and which had disseminated towards the end of the continent, promoted the deployment of different actions tending to make presence no...

Alien invasions and the game of hide and seek in Patagonia.

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Martin Lindegren

Full Text Available The introduction, establishment and spread of alien species is a major threat to biodiversity and the provision of ecosystem services for human wellbeing. In order to reduce further loss of biodiversity and maintain productive and sustainable ecosystems, understanding the ecological mechanisms underlying species invasions and avoiding potentially harmful effects on native communities is urgently needed, but largely lacking. We here demonstrate, by means of hydroacoustics and advanced spatial modelling, how native fish species as a result of previous exposure to native predators may successfully respond to invasive novel predators through a complicated game of hide and seek, minimizing spatio-temporal overlap with predators, and potentially facilitating coexistence between native prey species (Galaxiids and introduced novel predators (Salmonids in a deep Andean lake, Patagonia.

Respuesta dietaria de tres rapaces frente a una presa introducida en Patagonia Dietary response of three raptor species to an introduced prey in Patagonia

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ANA L. MONSERRAT

2005-09-01

Full Text Available Los depredadores de marcada respuesta funcional pueden poseer la capacidad de estabilizar las poblaciones de sus presas, lo cual es destacable en el caso de presas introducidas, que suelen causar impactos negativos en los ecosistemas nativos y las actividades agropecuarias. La situación actual de la Patagonia es crítica respecto a la introducción de especies. Estudios previos indican que los depredadores nativos exhiben un cambio general en sus dietas debido a la introducción de presas exóticas que están reemplazando a sus presas originales. Determinamos los hábitos alimenticios del águila (Geranoaetus melanoluecus, el búho magallánico (Bubo magellanicus y el aguilucho común (Buteo polyosoma, tres de las principales aves depredadoras de la liebre europea (Lepus europaeus, introducida en el noroeste de Patagonia. Para esto analizamos 321, 115 y 78 egagrópilas de águila, búho y aguilucho respectivamente. Evaluamos las respuestas funcionales a la densidad de liebre europea y comparamos las dietas entre sitios diferentes. Las principales presas del aguilucho y del búho fueron los roedores sigmodontinos y en segundo lugar los tuco-tucos (Ctenomys spp.. El águila consumió principalmente liebres y en segundo lugar tuco-tucos, presentando una respuesta funcional significativa para la presa introducida. La dieta de este rapaz fue diferente entre sitios con alta y baja densidad de liebres. Para los otros dos rapaces no encontramos una respuesta funcional significativa para la liebre europea, pero la dieta del aguilucho varió en función del sitio geográfico. Concluimos que tanto el águila mora como el aguilucho se alimentan de manera generalista, siendo el búho el único de los tres rapaces con tendencia especialista sobre pequeños roedores. Por otra parte, la variación de la dieta del águila en función de la densidad de liebre europea le brinda el potencial de contribuir a la regulación de las poblaciones de la misma

Mida õpetab Argentina finantskriis? / Karsten Staehr

Index Scriptorium Estoniae

Staehr, Karsten, 1962-

2002-01-01

Norra majandusanalüütik kirjeldab Argentina majanduspoliitikat, analüüsib tehtud vigu ning hoiatab avatud majandusega Eestit võimalike tulevaste välisshokkide eest. Diagramm: SKP kasv ja üleüldine riigieelarve tasakaal 1991-2001 Argentinas

Stereo-scopy of {gamma}-ray air showers with the H.E.S.S. telescopes: first images of the supernova remnants at TeV; Stereoscopie de gerbes de {gamma} avec les telescopes H.E.S.S.: premieres images de vestiges de supernovae au TeV

Energy Technology Data Exchange (ETDEWEB)

Lemoine-Goumard, Marianne [Ecole Polytechnique, 91128 Palaiseau Cedex (France)

2006-05-15

The H.E.S.S. (High Energy Stereoscopic System) experiment in gamma-ray Astronomy consists of four imaging atmospheric Cherenkov telescopes devoted to the observation of the gamma-ray sky in the energy domain above 100 GeV and extending up to several tens of TeV. This thesis presents a new reconstruction method of gamma-ray induced air showers which takes full advantage of the stereo-scopy and of the fine-grain imaging of the H.E.S.S. cameras. This new method provides an angular resolution better than 0.1 angle, an energy resolution of about 15% at zenith and a very efficient hadronic rejection based on a cut on the lateral spread of the electromagnetic shower which does not depend on simulations. A new background subtraction method, well adapted to the study of extended sources, was also developed. No assumption, either on the distribution of gamma-rays in the field of view, or on the distribution of hadrons are necessary. It provides two sky maps obtained from a maximum likelihood fit: one for {gamma}-rays and the other for hadrons. These two analysis methods were applied to the study of the shell-type supernova remnants RX J1713.7-3946 and RX J0852.0-4622 (Vela Junior), allowing for the first time to resolve their morphology in the gamma-ray domain. The study of these sources should answer the question: 'can shell-type supernova remnants accelerate cosmic-rays up to the knee (5 x 10{sup 15} eV)?'. A morphological and spectral study of these sources combined with a comparison of a simple model of emission processes (from electrons and protons accelerated in supernova remnants) provides some constraints on the parameters of the leptonic process. Nevertheless, this scenario cannot be excluded. The different results obtained are discussed and compared with a third shell-type supernova remnant observed by H.E.S.S. but not detected: SN 1006. (author)

Insights from gas and water chemistry on the geothermal system of the Domuyo volcanic complex (Patagonia, Argentina)

Science.gov (United States)

Tassi, F.; Liccioli, C.; Chiodini, G.; Agusto, M.; Caselli, A. T.; Caliro, S.; Vaselli, O.; Pecoraino, G.

2015-12-01

This study focuses on the geochemistry of geothermal fluids discharging from the western flank of the Domuyo volcanic complex (Argentina), which is hosted within an extensional basins that interrupts the Andes at latitudes comprises between 35° and 39°S. The analytical results of gas and water samples collected during three sampling campaigns (2013, 2014 and 2015) are presented and discussed in order to: i) evaluate the equilibrium temperature(s) of the main fluid reservoir, ii) provide information on the origin of the fluid discharges and the secondary processes controlling their chemistry. Geothermometry based on the chemical composition of thermal waters indicates a maximum equilibrium temperature of 220 °C. This temperature, coupled with the measured amount of discharged Cl, suggest that the total energy released from this system is 1.1±0.2 GW. Atmospheric gases from a thick shallow aquifer contaminate most gas emissions, masking the chemical features of the deep fluid component, with the only exception of a jet fumarole located at 3,000 m a.s.l. (Bramadora). The H2O-CO2-CH4-H2-CO-C3H6-C3H8 composition of this gas emission was used to construct a geochemical conceptual model showing that the hydrothermal reservoir is liquid-dominated and thermally stratified, with temperatures ranging from 180 to 270 °C. The helium isotopic ratios (up to 6.8 Ra) and the δ13C-CO2 values (from -7.05 to -7.75 ‰ V-PDB) indicate that mantle degassing represents the dominant primary source for this dormant volcano. These results highlight the huge potential of this system as energy resource for the region. Accordingly, the regional authorities have recently planned and approved an investigation project aimed to provide further insights into the fluid geochemistry and the geostructural assessment in this promising area.

Communications received from Argentina and Brazil

International Nuclear Information System (INIS)

1989-01-01

The document reproduces the Joint Statement on Nuclear Policy signed by the President of Argentina and the President of Brazil on 29 November 1988 at Ezeiza, Argentina, concerning the decision of the two countries to undertake a joint fast breeder reactor project

Argentina

International Nuclear Information System (INIS)

2001-04-01

This economical study summarizes the energy situation of Argentina: energy institutions and policy, energy companies (oil, electricity, gas, coal), energy supplies (resources, power production, petroleum, natural gas), prices and tariffs, consumption, economical stakes and perspectives (investments, agreements, projects). Energy data for the 1971-1999 period are summarized in graphs and tables. (J.S.)

Argentina: a mature urbanization pattern.

Science.gov (United States)

Rofman, A B

1985-02-01

"This article describes the historical development of Argentina's cities, pointing out the traditional dominance of the 'centre-litoral' region and...[of] Buenos Aires. Recent trends such as the population increase in the southern region are described and demographic trends are related to economic developments. The article concludes by examining Argentina's contemporary urban patterns, including the current low rate of urbanization." excerpt

Argentina's radioactive waste disposal policy

International Nuclear Information System (INIS)

Palacios, E.

1986-01-01

The Argentina policy for radioactive waste disposal from nuclear facilities is presented. The radioactive wastes are treated and disposed in confinement systems which ensure the isolation of the radionucles for an appropriate period. The safety criteria adopted by Argentina Authorities in case of the release of radioactive materials under normal conditions and in case of accidents are analysed. (M.C.K.) [pt

LDC nuclear power: Argentina

International Nuclear Information System (INIS)

Tweedale, D.L.

1982-01-01

Argentina's 31-year-old nuclear research and power program makes it a Third World leader and the preeminent Latin American country. Easily accessible uranium fuels the heavy water reactor, Atucha I, which provides 10% of the country's electric power. Atucha II and III are under construction. Several domestic and international factors combined to make Argentina's program succeed, but achieving fuel-cycle independence and the capacity to divert fissionable material to military uses is a cause for some concern. 60 references

How many populations set foot through the Patagonian door? Genetic composition of the current population of Bahía Blanca (Argentina) based on data from 19 Alu polymorphisms.

Science.gov (United States)

Resano, M; Esteban, E; González-Pérez, E; Vía, M; Athanasiadis, G; Avena, S; Goicoechea, A; Bartomioli, M; Fernández, V; Cabrera, A; Dejean, C; Carnese, F; Moral, P

2007-01-01

The city of Bahía Blanca occupies a strategic place in Argentina south of the Pampean region in the north-east corner of the Patagonia. Since 1828, this city has been the historical and political border between Amerindian lands in the south, and the lands of European colonists. Nowadays, Bahía Blanca is an urban population mainly composed by descendents of immigrants from Spain and other European countries with apparently low admixture with Amerindians. In view of the unexpectedly high Amerindian admixture levels (about 46.7%) suggested by mtDNA data, and protein markers (19.5%), we analyzed a set of 19 Alu polymorphisms (18 autosomal, 1 of Chromosome Y) in a well-documented genealogical sample from Bahía Blanca. The genotyped sample was made up of 119 unrelated healthy individuals whose birth place and grandparent origins were fully documented. According to available genealogical records, the total sample has been subdivided into two groups: Bahía Blanca Original (64 individuals with all 4 gandparents born in Argentina) and Bahía Blanca Mix (55 individuals with one to three grandparents born out of Argentina). Allele frequencies and gene diversity values in Bahía Blanca fit well into the European ranges. Population relationships have been tested for 8 Alu markers, whose variation has been described in several Amerindian and European samples. Reynolds genetic distances underline the significant genetic similarity of Bahía Blanca to Europeans (mean distance 0.044) and their differentiation from Amerindians (0.146). Interestingly enough, when the general sample is divided, Bahía Blanca Original appears slightly closer to Amerindians (0.127) in contrast to Bahía Blanca Mix (0.161). Furthermore, the genetic relationships depicted through a principal components analysis emphasize the relative similarity of Bahía Blanca Original to Amerindians. A thorough knowledge of the sample origins has allowed us to make a subtle distinction of the genetic composition of

A promising location in Patagonia for paleoclimate and paleoenvironmental reconstructions revealed by shallow firn core from Monte San Valentin (Northern patagonia Icefield, Chile)

DEFF Research Database (Denmark)

Vimeux, F.; de Angelis, M.; Ginot, P.

2008-01-01

temperature is -11.9°C at 10-m depth allowing to expect well preserved both chemical and isotopic signals, unperturbed by water percolation. The dating of the core, on the basis of a multi-proxy approach combining annual layer counting and radionuclide measurements, shows that past environment and climate can......The study of past climate variability from ice core investigations has been largely developed both in polar areas over the past decades and, more recently, in tropical regions, specifically along the South American Andes between 0° and 20°S. However a large gap still remains at mid......-latitudes in the Southern Hemisphere. In this framework, a 15.3-m long shallow firn core has been extracted in March 2005 from the summit plateau of Monte San Valentín (3747 m, 46°35'S, 73°19'W) in the Northern Patagonia Icefield to test its potential for paleoclimate and paleoenvironmental reconstructions. The firn...

Distribución del ictioplancton en la Patagonia austral de Chile: potenciales efectos del deshielo de Campos de Hielo Sur Ichthyoplankton distribution in South Patagonia, Chile: potential effects of ice melting from the Southern Ice Field

Directory of Open Access Journals (Sweden)

Mauricio F Landaeta

2011-07-01

Full Text Available Durante octubre-noviembre de 2009 se realizó un crucero oceanográfico entre 50 y 53°S de Chile austral, en las cercanías del glaciar Campos de Hielo Sur. Las estaciones cercanas al glaciar presentaron baja temperatura (1-3°C y salinidad ( 0,1 ciclos s-1. Los principales taxa del ictioplancton fueron huevos y larvas de sardina fueguina Sprattus fuegensis, pez hacha Maurolicus parvipinnis, Macrouridae y merluza austral Merluccius australis. El desove principal de S. fuegensis (~ 8000 huevos 10 m-2 ocurrió en zonas mezcladas de la plataforma continental adyacente, mientras que el desove de M. parvipinnis ocurrió en canales intermedios asociado a valores intermedios de estabilidad (N~0,06 ciclos s-1. Se observó una nula o baja abundancia de huevos y larvas de peces en las cercanías del glaciar, y la abundancia de huevos de M. parvipinnis estuvo relacionada positivamente con la temperatura y salinidad de la columna de agua y negativamente con la estabilidad de la columna de agua. Además, hubo una relación negativa entre la densidad del agua de mar y el diámetro de los huevos de S. fuegensis. La relación entre deshielo e ictioplancton podría tener consecuencias en el transporte advectivo y mortalidad masiva de huevos y larvas de peces y el acople pelágico-bentónico en la Patagonia austral de Chile. Como el cambio climático global ha incrementado los deshielos de glaciares en latitudes altas, y el aumento del ingreso de aguas de baja temperatura y salinidad podría tener consecuencias en el ictioplancton de la Patagonia chilena.In October-November 2009, an oceanographic survey was carried out between 50 and 53°S off southern Chile, near the Southern Ice Field. The stations near the glacier showed low temperatures (1-3°C and salinity ( 0.1 cycles s-1. Main ichthyoplankton taxa were eggs and larvae of southern sprat Sprattus fuegensis, lightfish Maurolicus parvipinnis, Macrouridae, and southern hake Merluccius australis. The main

A new sauropodomorph dinosaur from the Early Jurassic of Patagonia and the origin and evolution of the sauropod-type sacrum.

Directory of Open Access Journals (Sweden)

Diego Pol

2011-01-01

Full Text Available The origin of sauropod dinosaurs is one of the major landmarks of dinosaur evolution but is still poorly understood. This drastic transformation involved major skeletal modifications, including a shift from the small and gracile condition of primitive sauropodomorphs to the gigantic and quadrupedal condition of sauropods. Recent findings in the Late Triassic-Early Jurassic of Gondwana provide critical evidence to understand the origin and early evolution of sauropods.A new sauropodomorph dinosaur, Leonerasaurus taquetrensis gen. et sp. nov., is described from the Las Leoneras Formation of Central Patagonia (Argentina. The new taxon is diagnosed by the presence of anterior unserrated teeth with a low spoon-shaped crown, amphicoelous and acamerate vertebral centra, four sacral vertebrae, and humeral deltopectoral crest low and medially deflected along its distal half. The phylogenetic analysis depicts Leonerasaurus as one of the closest outgroups of Sauropoda, being the sister taxon of a clade of large bodied taxa composed of Melanorosaurus and Sauropoda.The dental and postcranial anatomy of Leonerasaurus supports its close affinities with basal sauropods. Despite the small size and plesiomorphic skeletal anatomy of Leonerasaurus, the four vertebrae that compose its sacrum resemble that of the large-bodied primitive sauropods. This shows that the appearance of the sauropod-type of sacrum predated the marked increase in body size that characterizes the origins of sauropods, rejecting a causal explanation and evolutionary linkage between this sacral configuration and body size. Alternative phylogenetic placements of Leonerasaurus as a basal anchisaurian imply a convergent acquisition of the sauropod-type sacrum in the new small-bodied taxon, also rejecting an evolutionary dependence of sacral configuration and body size in sauropodomorphs. This and other recent discoveries are showing that the characteristic sauropod body plan evolved gradually

Operating practical experience at Argentina

International Nuclear Information System (INIS)

Quihillalt, Oscar

1997-01-01

Operating experiences of Atucha-1 and Embalse Nuclear Power Plants were discussed in this work. The technical and economic aspects, such as reliability, availability, personnel training, operating costs, prices and market, which exercise influence upon Argentina nuclear energy policy, mainly on the power electric generation by nuclear power plants were considered. Finally the current status of the nucleoelectric sector in Argentina and forecasting were analysed

Boll weevil invasion process in Argentina

Science.gov (United States)

The boll weevil, Anthonomus grandis grandis Boheman, is the most destructive cotton pest in the Western Hemisphere. In 1993, the pest was reported in Argentina, and in 1994 boll weevils were captured in cotton fields in the Formosa Province on the border between Argentina and Paraguay. The pest ha...

Revisión de la distribución de Hyalella Smith, 1874 (Crustacea, Amphipoda) en la Patagonia e islas adyacentes Revision of the distribution of Hyalella Smith, 1874 (Crustacea, Amphipoda) in Patagonia and adjacent islands

OpenAIRE

Patricio De los Ríos-Escalante; Andrés Mansilla; Christopher B Anderson

2012-01-01

Se realiza una revisión de las especies de anfípodos del género Hyalella en aguas continentales de la Patagonia, isla Tierra del Fuego, Reserva de la Biosfera de Cabo de Hornos e islas adyacentes (38-54°S). Esta zona austral presenta numerosos tipos de ambientes acuáticos continentales como lagos, humedales y arroyos, y las principales especies en ambientes bentónicos corresponden a anfípodos del género Hyalella. La bibliografía menciona la presencia de H. costera, H. chiloensis, H. falklande...

Foraging Behavior Interactions Between Two non-Native Social Wasps, Vespula germanica and V. vulgaris (Hymenoptera: Vespidae): Implications for Invasion Success?

OpenAIRE

Pereira, Ana Julia; Pirk, Gabriela I.; Corley, Juan C.

2016-01-01

Vespula vulgaris is an invasive scavenging social wasp that has very recently arrived in Patagonia (Argentina), a territory previously invaded ? 35 yrs earlier ? by another wasp, Vespula germanica. Although V. vulgaris wasps possess features that could be instrumental in overcoming obstacles through several invasion stages, the presence of preestablished populations of V. germanica could affect their success. We studied the potential role played by V. germanica on the subsequent invasion proc...

Un primitivo Notonychopidae (Litopterna del Paleoceno inferior de Punta Peligro, Chubut, Argentina

Directory of Open Access Journals (Sweden)

Morales, J.

1997-12-01

Full Text Available The discovery of a new ungulate species, Requisia vidmari gen. nov., nov. sp. in the lower Paleocene of Punta Peligro, Chubut (Argentine represents the earliest known record of Litopterna. The dental morphology of this new genus is very similar to that known for Notonychops powelli Soria, 1989, differing mainly by its more primitive M3, which is less elongated and less selenodont. Requisia vidmari, together with Wainka tshotshe Simpson, 1948, can be included in the family Notonychopidae, which appear to represent an ancestral grade in the evolution of Litopterna. Because cladogenesis of South American ungulates clearly took place prior to the Punta Peligro fauna and was apparently rapid, phylogenetic interpretation is difficult.Se comunica un nuevo ungulado con dentición pre-selenodonta del Paleoceno inferior, Peligrense, de Patagonia, Argentina. Su morfología dentaria es muy similar a la de Notonychops powelli Soria, 1989, pero con caracteres más primitivos. La morfología de las cúspides, el tipo de desgaste y los caracteres crescentiformes del M3 indican que Requisia vidmari gen. nov., sp. nov. presenta fuertes evidencias del desarrollo de caracteres selenodontos, por lo que se lo considera como el más primitivo representante del orden Litopterna. Requisia vidmari y probablemente Wainka tshotshe Simpson, 1948, son primitivos en relación a Notonychops, pero su similitud morfológica justificaría su inclusión en la misma familia Notonychopidae. Se considera que la radiación adaptativa de los ungulados paleocenos de América del Sur fue precoz, eventualmente rápida, lo que dificulta encontrar un modelo filogenético suficientemente explicativo.

Very high energy gamma-ray astronomy with H.E.S.S. Development of a multivariate analysis and application to study of pulsar wind nebulae

International Nuclear Information System (INIS)

Dubois, Florent

2009-01-01

H.E.S.S. (High Energy Stereoscopic System) is one of the leading systems of four Imaging Atmospheric Cherenkov Telescopes that investigates very high energy (VHE) cosmic gamma-rays in the 100 GeV to 100 TeV energy range. H.E.S.S. is located in Namibia, near the Gamsberg mountain and operational since December 2003. The H.E.S.S. experiment is mainly aimed to the observation of the southern sky including the galactic plan and the numerous astrophysics sources therein. Three analysis methods have been developed using various properties of the electromagnetic showers generated by the interaction of primary cosmic gamma-rays within the Earth atmosphere. The first goal of this thesis was to combine the information from these methods for the selection and the energy and direction reconstruction of gamma-ray events. The new analysis called X eff improves significantly the quality of the selection and the precision of the reconstruction. This analysis has been afterwards applied to the study of pulsar wind nebulae like Vela X, G0.9+0.1 and MSH 15-52. New results were found concerning the source extension (Vela X) or spectral analysis (G0.9+0.1 and MSH 15-52) at TeV energies, thanks to additional data and to the improved efficiency of the new method. In 2010, a new phase will begin with the achievement of a fifth telescope dedicated to gamma-ray observation from tens GeV. The calibration processes of the photomultipliers equipping the camera of the new telescope, as well as the results of the tests, are also described in this thesis. (author)

Argentina

International Nuclear Information System (INIS)

Masters, R.

1997-01-01

This article provides information on the energy resources, government, electricity supply, nuclear industry and fuel cycle of Argentina. About 12% of electric power produced is generated from nuclear power plants. The operating capacity, history and partial privatisation of the nuclear industry are covered, and fuel cycle facilities described. These include uranium mining and processing, enrichment, fuel fabrication and heavy water production. (UK)

Relativistic density functional theory with picture-change corrected electron density based on infinite-order Douglas-Kroll-Hess method

Science.gov (United States)

Oyama, Takuro; Ikabata, Yasuhiro; Seino, Junji; Nakai, Hiromi

2017-07-01

This Letter proposes a density functional treatment based on the two-component relativistic scheme at the infinite-order Douglas-Kroll-Hess (IODKH) level. The exchange-correlation energy and potential are calculated using the electron density based on the picture-change corrected density operator transformed by the IODKH method. Numerical assessments indicated that the picture-change uncorrected density functional terms generate significant errors, on the order of hartree for heavy atoms. The present scheme was found to reproduce the energetics in the four-component treatment with high accuracy.

Long-term landscape evolution of the South Atlantic "passive" continental margin in Eastern Argentina using apatite fission-track thermochronology

Science.gov (United States)

Pfister, Sabrina; Kollenz, Sebastian; Glasmacher, Ulrich A.

2015-04-01

spontaneous fission-tracks and were used to test geological t-T models against the AFT data set. These models will lead to a more detailed insight on the cooling history and tectonic activities in the research area. In addition there will be an outlook on further models including AFT, ZrFT and ZrHe data, which show that the Sierras Septentrionales seems to be influenced by the folding and wrenching of the neighboring Sierras Australes (Rosello et al. 1997). References Cingolani, C. A. The Tandilia System of Argentina as a southern extension of the Río de la Plata craton: an overview. International Journal of Earth Sciences 100, 221-242 (2011). Demoulin, A., Zarate, M., Rabassa, J. Longterm landscape development: a perspective from the southern Buenos Aires ranges of east central Argentina. Journal of South American Earth Sciences 19, 193-204 (2005). Ketcham, R. A. Forward and inverse modeling of low-temperature thermochronometry data, in Low-Temperature Thermochronology: Techniques, Interpretations, and Applications (eds. by Reiners, P. W. & Ehlers, T. A.) 275-314 (Mineralogical Society of America/Geochemical Society Reviews in Mineralogy and Geochemistry, Chantilly, Virginia, 2005). Ketcham, R. A., et al. Improved modeling of fission-track annealing in apatite. American Mineralogist, 92, 789-798 (2007). Ketcham, R. A., Donelick, R. A., Balestrieri, M. L., Zattin, M. Reproducibility of apatite fission-track length data and thermal history reconstruction, Earth and Planetary Science Letters 284, 504-515 (2009). Rossello, E.A.; Massabie, C.; Lopez- Gamundi, O.R.; Cobbold, P.R.; Gapais, d.; 1997: Late Paleozoic transpression in Buenos Aires and northeast Patagonia ranges, Argentina Journal of South American Earth Sciences, 10 (5-6), pp.389-402. Zalba, P. E., Manassero, M., La Verret, E., Beaufort, D., Meunier, A., Morosi, M., Segovia, L. Middle Permian telodiagenetic processes in Neoproterozoic sequences, Tandilia System, Argentina. Int. J. of Sed. Res. 77, 525-538 (2007).

Diccionario del español de Argentina

OpenAIRE

Haensch, Günther

2000-01-01

Diccionario del español de Argentina : español de Argentina - español de España / Günther Haensch ; Reinhold Werner. Madrid : Gredos, 2000. - LI, 729 S. - (Diccionarios contrastivos del español de América)

Characterising the VHE diffuse emission in the central 200 parsecs of our Galaxy with H.E.S.S.

Science.gov (United States)

H.E.S.S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Andersson, T.; Angüner, E. O.; Arakawa, M.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bonnefoy, S.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Büchele, M.; Bulik, T.; Capasso, M.; Carr, J.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Coffaro, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'C.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holch, T. L.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khélifi, B.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Rauth, R.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Richter, S.; Rieger, F.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Saito, S.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stycz, K.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Żywucka, N.

2018-04-01

The diffuse very high-energy (VHE; >100 GeV) γ-ray emission observed in the central 200 pc of the Milky Way by H.E.S.S. was found to follow dense matter distribution in the central molecular zone (CMZ) up to a longitudinal distance of about 130 pc to the Galactic centre (GC), where the flux rapidly decreases. This was initially interpreted as the result of a burst-like injection of energetic particles 104 yr ago, but a recent more sensitive H.E.S.S. analysis revealed that the cosmic-ray (CR) density profile drops with the distance to the centre, making data compatible with a steady cosmic PeVatron at the GC. In this paper, we extend this analysis to obtain, for the first time, a detailed characterisation of the correlation with matter and to search for additional features and individual γ-ray sources in the inner 200 pc. Taking advantage of 250 h of H.E.S.S. data and improved analysis techniques, we perform a detailed morphology study of the diffuse VHE emission observed from the GC ridge and reconstruct its total spectrum. To test the various contributions to the total γ-ray emission, we used an iterative 2D maximum-likelihood approach that allows us to build a phenomenological model of the emission by summing a number of different spatial components. We show that the emission correlated with dense matter covers the full CMZ and that its flux is about half the total diffuse emission flux. We also detect some emission at higher latitude that is likely produced by hadronic collisions of CRs in less dense regions of the GC interstellar medium. We detect an additional emission component centred on the GC and extending over about 15 pc that is consistent with the existence of a strong CR density gradient and confirms the presence of a CR accelerator at the very centre of our Galaxy. We show that the spectrum of full ridge diffuse emission is compatible with that previously derived from the central regions, suggesting that a single population of particles fills the

The supernova remnant W49B as seen with H.E.S.S. and Fermi-LAT

Science.gov (United States)

H. E. S. S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Benkhali, F. Ait; Akhperjanian, A. G.; Andersson, T.; Angüner, E. O.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Tjus, J. Becker; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Bulik, T.; Capasso, M.; Carr, J.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chalme-Calvet, R.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Chrétien, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'C.; Dubus, G.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hadasch, D.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holler, M.; Horns, D.; Ivascenko, A.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katz, U.; Kerszberg, D.; Khélifi, B.; Kieffer, M.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krayzel, F.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Naurois, M. de; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Öttl, S.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; los Reyes, R. de; Rieger, F.; Romoli, C.; Rosier-Lees, S.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stinzing, F.; Stycz, K.; Sushch, I.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; Eldik, C. van; Rensburg, C. van; Soelen, B. van; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Żywucka, N.; Fermi-LAT Collaboration; Katsuta, J.

2018-04-01

The supernova remnant (SNR) W49B originated from a core-collapse supernova that occurred between one and four thousand years ago, and subsequently evolved into a mixed-morphology remnant, which is interacting with molecular clouds (MC). Gamma-ray observations of SNR-MC associations are a powerful tool to constrain the origin of Galactic cosmic rays, as they can probe the acceleration of hadrons through their interaction with the surrounding medium and subsequent emission of non-thermal photons. We report the detection of a γ-ray source coincident with W49B at very high energies (VHE; E > 100 GeV) with the H.E.S.S. Cherenkov telescopes together with a study of the source with five years of Fermi-LAT high-energy γ-ray (0.06-300 GeV) data. The smoothly connected, combined source spectrum, measured from 60 MeV to multi-TeV energies, shows two significant spectral breaks at 304 ± 20 MeV and 8.4-2.5+2.2 GeV; the latter is constrained by the joint fit from the two instruments. The detected spectral features are similar to those observed in several other SNR-MC associations and are found to be indicative of γ-ray emission produced through neutral-pion decay. The H.E.S.S. gamma-ray excess map (see Fig. 1, in FITS format) of the W49 region is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/612/A5

Argentina

International Nuclear Information System (INIS)

Anon.

1992-01-01

This paper reports that like so many other countries, Argentina is in the throes of privatization and restructuring of its economic programs. This has had a direct effect on the LPG industry. Argentina is a country with many natural resources. However, natural gas and crude, while present, are not in abundance. Imports of these and their associated products are needed to satisfy the growing need of the population from time to time. This is especially true with LPGs. Production of the fuel averages about 1 million tons, not enough to satisfy internal needs in the winter but enough to permit some exports in the summer to nearby Brazil. The Country's Congress approved a plan to sell-off or lease parts of the natural gas distribution network and other businesses of Gas del Estado. Subsequent new legislation has called for ten new natural gas distribution zones. Included in the sell-off is the company's propane distribution division. What is left of Gas del Estado and YPF will become a corporation in the true sense of the word. Stocks in YPF are to be sold to the public

Reactor catastrophe in Chernobyl and the consequences in the area of Eastern Hesse. Reaktorkatastrophe in Tschernobyl und die Folgen in der osthessischen Region

Energy Technology Data Exchange (ETDEWEB)

Diel, F; Meier-Ploeger, A

1986-01-01

In this booklet a short assessment of the reactor accident and the resulting radioactive contamination in the area of Eastern Hesse is described. The authors are referring for the most part to results of an investigation carried out by the Umwelt- und Diagnoselabor Fulda (ULF) with the help of the population of Fulda in May 1986.

A Cambrian mixed carbonate-siliciclastic platform in SW Gondwana: evidence from the Western Sierras Pampeanas (Argentina) and implications for the early Paleozoic paleogeography of the proto-Andean margin

Science.gov (United States)

Ramacciotti, Carlos D.; Casquet, César; Baldo, Edgardo G.; Galindo, Carmen; Pankhurst, Robert J.; Verdecchia, Sebastián O.; Rapela, Carlos W.; Fanning, Mark

2018-05-01

The Western Sierras Pampeanas (WSP) of Argentina record a protracted geological history from the Mesoproterozoic assembly of the Rodinia supercontinent to the early Paleozoic tectonic evolution of SW Gondwana. Two well-known orogenies took place at the proto-Andean margin of Gondwana in the Cambrian and the Ordovician, i.e., the Pampean (545-520 Ma) and Famatinian (490-440 Ma) orogenies, respectively. Between them, an extensive continental platform was developed, where mixed carbonate-siliciclastic sedimentation occurred. This platform was later involved in the Famatinian orogeny when it underwent penetrative deformation and metamorphism. The platform apparently extended from Patagonia to northwestern Argentina and the Eastern Sierras Pampeanas, and has probable equivalents in SW Africa, Peru, and Bolivia. The WSP record the outer (deepest) part of the platform, where carbonates were deposited in addition to siliciclastic sediments. Detrital zircon U-Pb SHRIMP ages from clastic metasedimentary successions and Sr-isotope compositions of marbles from the WSP suggest depositional ages between ca. 525 and 490 Ma. The detrital zircon age patterns further suggest that clastic sedimentation took place in two stages. The first was sourced mainly from re-working of the underlying Neoproterozoic metasedimentary rocks and the uplifted core of the early Cambrian Pampean orogen, without input from the Paleoproterozoic Río de la Plata craton. Sediments of the second stage resulted from the erosion of the still emerged Pampean belt and the Neoproterozoic Brasiliano orogen in the NE with some contribution from the Río de la Plata craton. An important conclusion is that the WSP basement was already part of SW Gondwana in the early Cambrian, and not part of the exotic Precordillera/Cuyania terrane, as was previously thought.

The diet of the South American sea lion (Otaria flavescens at Río Negro, Patagonia, Argentina, during the winter-spring period

Directory of Open Access Journals (Sweden)

Raimundo L. Bustos

2012-12-01

Full Text Available The South American sea lion, Otaria flavescens (Shaw, 1800 population is steadily expanding along the Patagonian coast of Argentina in the last decades. However, little is known about the feeding ecology of the species in the area. The aim of this study was to analyze the food habits of O. flavescens from 91 scats collected at Río Negro province, during the winter and spring of 2005. Fish occurred in 96% of scats containing prey remains, followed by cephalopods (26%. Raneya brasiliensis (Kaup, 1856 was the most frequent and abundant species occurring in 58.6% of samples and constituting almost 50% of fish predated. Second in importance were Porichthys porosissimus (Cuvier, 1829 and Cynoscion guatucupa (Cuvier, 1830 in terms of occurrence (%FO 20.7 and numbers (29.6% respectively. The squid Loligo gahi (d'Orbigny, 1835 was the most frequent cephalopod prey (42.1%, whereas Octopus tehuelchus (d'Orbigny, 1834 was the most abundant (77%. The higher amount and diversity of prey found in the spring in comparison with the winter season might be related to a higher feeding activity of seals or to a seasonal increase in food availability in the area.

Regional Extinctions and Quaternary Shifts in the Geographic Range of Lestodelphys halli, the Southernmost Living Marsupial: Clues for Its Conservation.

Directory of Open Access Journals (Sweden)

Anahí E Formoso

Full Text Available The Patagonian opossum (Lestodelphys halli, the southernmost living marsupial, inhabits dry and open environments, mainly in the Patagonian steppe (between ~32 °S and ~49 °S. Its rich fossil record shows its occurrence further north in Central Argentina during the Quaternary. The paleoenvironmental meaning of the past distribution of L. halli has been mostly addressed in a subjective framework without an explicit connection with the climatic "space" currently occupied by this animal. Here, we assessed the potential distribution of this species and the changes occurred in its geographic range during late Pleistocene-Holocene times and linked the results obtained with conservation issues. To this end, we generated three potential distribution models with fossil records and three with current ones, using MaxEnt software. These models showed a decrease in the suitable habitat conditions for the species, highlighting a range shift from Central-Eastern to South-Western Argentina. Our results support that the presence of L. halli in the Pampean region during the Pleistocene-Holocene can be related to precipitation and temperature variables and that its current presence in Patagonia is more related to temperature and dominant soils. The models obtained suggest that the species has been experiencing a reduction in its geographic range since the middle Holocene, a process that is in accordance with a general increase in moisture and temperature in Central Argentina. Considering the findings of our work and the future scenario of global warming projected for Patagonia, we might expect a harsh impact on the distribution range of this opossum in the near future.

Regional Extinctions and Quaternary Shifts in the Geographic Range of Lestodelphys halli, the Southernmost Living Marsupial: Clues for Its Conservation

Science.gov (United States)

Formoso, Anahí E.; Martin, Gabriel M.; Teta, Pablo; Carbajo, Aníbal E.; Sauthier, Daniel E. Udrizar; Pardiñas, Ulyses F. J.

2015-01-01

The Patagonian opossum (Lestodelphys halli), the southernmost living marsupial, inhabits dry and open environments, mainly in the Patagonian steppe (between ~32°S and ~49°S). Its rich fossil record shows its occurrence further north in Central Argentina during the Quaternary. The paleoenvironmental meaning of the past distribution of L. halli has been mostly addressed in a subjective framework without an explicit connection with the climatic “space” currently occupied by this animal. Here, we assessed the potential distribution of this species and the changes occurred in its geographic range during late Pleistocene-Holocene times and linked the results obtained with conservation issues. To this end, we generated three potential distribution models with fossil records and three with current ones, using MaxEnt software. These models showed a decrease in the suitable habitat conditions for the species, highlighting a range shift from Central-Eastern to South-Western Argentina. Our results support that the presence of L. halli in the Pampean region during the Pleistocene-Holocene can be related to precipitation and temperature variables and that its current presence in Patagonia is more related to temperature and dominant soils. The models obtained suggest that the species has been experiencing a reduction in its geographic range since the middle Holocene, a process that is in accordance with a general increase in moisture and temperature in Central Argentina. Considering the findings of our work and the future scenario of global warming projected for Patagonia, we might expect a harsh impact on the distribution range of this opossum in the near future. PMID:26203650

Cross-sectional survey in pig breeding farms in Hesse, Germany: seroprevalence and risk factors of infections with Toxoplasma gondii, Sarcocystis spp. and Neospora caninum in sows

DEFF Research Database (Denmark)

Damriyasa, I.M.; Bauer, C.; Edelhofer, R.

2004-01-01

A cross-sectional survey was performed to estimate the prevalences of antibodies to Toxoplasma gondii (ELISA, IFAT), Sarcocystis spp. (ELISA, using S. miescheriana as antigen) and Neospora caninum (ELISA, immunoblotting) in sows from breeding farms in southern Hesse, Germany. A total of 2041 plas...

Diacronía y sincronía del contacto lingüístico en Patagonia sur

OpenAIRE

Virkel, Ana Ester

2012-01-01

Desde su integración al Estado argentino, la región patagónica fue receptora de inmigrantes de muy diversas procedencias, quienes, integrándose con las etnias aborígenes preexistentes, configuraron un contexto multiétnico y multicultural, con la consiguiente diversidad lingüística. El propósito de este trabajo es trazar un esquemático itinerario a través de la historia lingüística de Chubut, Patagonia sur, focalizando el interés en una serie de procesos migratorios que impactan de modo sus...

The System of Mountain Refuges in National Park Nahuel Huapi: contributions to sustainable development of Bariloche [Argentina

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Verónica Skavarca

2010-12-01

Full Text Available The Nahuel Huapi National Park, located at the northwest of the Andean Patagonia in Argentina, has a Mountain Refuge System composed of natural and cultural heritage assets, of heritage and landscape value. Analyzed as regards the socio-territorial identity, to reflect on its value as a cultural asset, it sets out a series of actions for citizen participation in its value as a local heritage in common and as a tourism resource for the generation of an ethical commitment to promote a balanced management. In order to make recommendations for use as a resource for local development, it examines the economic profile of the city and the statements of Sustainable Development and the Sustainable Tourism Charter. Under the current framework, we analyze the endogenous factors and encourages the implementation of a Management Plan, -to be considered in a Territorial Local Development Plan- which embraces the appropriation of this heritage and to provide environmental transfer tools through education and architecture, pondering its dissemination to all users of information. This particular system and the Circuit of the Four Shelters, is promoted as a living model of transfer of good practices in sustainable tourism and local development factor, considering the mechanism to rationally manage natural capital and the local heritage, to so that the community can continue to benefit from the goods and services of this ecosystem in a rational and enduring way

Does Nature and Persistence of Substrate at a Mesohabitat Scale Matter for Chironomidae Assemblages? a Study of Two Perennial Mountain Streams in Patagonia, Argentina

Science.gov (United States)

Epele, Luis Beltrán; Miserendino, María Laura; Brand, Cecilia

2012-01-01

of the Chironomidae assemblage at the habitat scale is significant for conservation purposes and for the management of low order streams in Patagonia. PMID:22947060

Does nature and persistence of substrate at a mesohabitat scale matter for Chironomidae assemblages? A study of two perennial mountain streams in Patagonia, Argentina.

Science.gov (United States)

Epele, Luis Beltrán; Miserendino, María Laura; Brand, Cecilia

2012-01-01

Chironomidae assemblage at the habitat scale is significant for conservation purposes and for the management of low order streams in Patagonia.

Genetic background and climatic droplet keratopathy incidence in a Mapuche population from Argentina.

Science.gov (United States)

Schurr, Theodore G; Dulik, Matthew C; Cafaro, Thamara A; Suarez, María F; Urrets-Zavalia, Julio A; Serra, Horacio M

2013-01-01

To determine whether the incidence of and susceptibility to climatic droplet keratopathy (CDK), an acquired, often bilateral degenerative corneal disease, is influenced by the genetic background of the individuals who exhibit the disorder. To determine whether the disease expression was influenced by the genetic ancestry of CDK cases in native Mapuche of the northwest area of Patagonia in Argentina, we examined mitochondrial DNA and Y-chromosome variation in 53 unrelated individuals. Twenty-nine of them were part of the CDK (patient) population, while 24 were part of the control group. The analysis revealed the maternal and paternal lineages that were present in the two study groups. This analysis demonstrated that nearly all persons had a Native American mtDNA background, whereas 50% of the CDK group and 37% of the control group had Native American paternal ancestry, respectively. There was no significant difference in the frequencies of mtDNA haplogroups between the CDK patient and control groups. Although the Y-chromosome data revealed differences in specific haplogroup frequencies between these two groups, there was no statistically significant relationship between individual paternal genetic backgrounds and the incidence or stage of disease. These results indicate a lack of correlation between genetic ancestry as represented by haploid genetic systems and the incidence of CDK in Mapuche populations. In addition, the mtDNA appears to play less of a role in CDK expression than for other complex diseases linked to bioenergetic processes. However, further analysis of the mtDNA genome sequence and other genes involved in corneal function may reveal the more precise role that mitochondria play in the expression of CDK.

The health crisis in Argentina.

Science.gov (United States)

Escudero, José Carlos

2003-01-01

The health crisis in Argentina is part of the larger crisis that has resulted from a collapse in the country's economic and political systems. After a brief review of the country's history over the last century, from international success story to economic failure, the author explains the health crisis in particular and the social crisis in general in terms of failed neoliberal policies imposed on Argentina by the United States and International Monetary Fund through the mediation of the country's political class.

Novedades en la Distribución de las Cyatheaceae (Pteridophyta en Argentina Novelties in the distribution of Cyatheaceae (Pteridophyta of Argentina

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Gonzalo J. Marquez

2006-12-01

Full Text Available Cyathea atrovirens (Langsd. & Fisch. Domin se cita por primera vez para la provincia de Corrientes (Argentina. De esta manera se extiende su área de distribución hacia el sudoeste. Además se confirma la presencia de Alsophila odonelliana (Alston M. Lehnert en la provincia de Jujuy (Argentina. En este estudio los caracteres de las esporas resultaron diagnósticos para la determinación genérica de los taxa.Cyathea atrovirens (Langsd. & Fisch. Domin is reported for the first time for Corrientes province (Argentina. Thus, its area of distribution is extended southwest. The presence of Alsophila odonelliana (Alston M. Lehnert is confirmed for Jujuy province (Argentina. In this study the spore features were diagnostic in order to determine these taxa.

Guanaco’s diet and forage preferences in Nothofagus forest environments of Tierra del Fuego, Argentina

Energy Technology Data Exchange (ETDEWEB)

Quinteros, C.P.; Bava, J.; Gobbi, M.E.; Defossé, G.E.

2017-11-01

Aim of study: Guanaco (Lama guanicoe Müller), is a South American native ungulate widely distributed in Patagonia, which in the island of Tierra del Fuego (TF), extends its habitat into Nothofagus spp. forests. Within these forests, guanacos consume lenga (Nothofagus pumilio) leaves and twigs, and other understory species. The aim of this work was to determine: 1) the spring and summer diet of free ranging guanacos, and 2) which plants, grown in the forest understory, guanacos do prefer, or avoid, in these seasons of great forage abundance. Area of study: Tierra del Fuego (Argentina), on three representative areas which combined Nothofagus forests and adjacent meadows (vegas). Material and Methods: uanacos’ diet was determined by comparing epidermal and non-epidermal plant fragments with micro-histological analyses of feces. The analysis was made from composite samples of fresh feces, collected at the seasons of maximum forage productivity (spring and summer). Main results: During spring, 48% of guanacos’ diet was composed of lenga leaves, 30% of grass-like species, 15% of grasses, and less than 7% of herbs, shrubs, and lichens. In summer, 40% of the diet was composed of grasses, 30% of lenga leaves, 25% of grass-like species and the rest corresponded to herbs, shrubs, and lichens. Within the forest understory, guanaco selected lenga leaves and twigs, grass species were consumed according to their availability (or sometimes rejected), while other herbs were not consumed at all. Research highlights: Guanacos’ consumption preference for lenga, even considering the high availability of other forages, could adversely affect forest regeneration.

Guanaco’s diet and forage preferences in Nothofagus forest environments of Tierra del Fuego, Argentina

International Nuclear Information System (INIS)

Quinteros, C.P.; Bava, J.; Gobbi, M.E.; Defossé, G.E.

2017-01-01

Aim of study: Guanaco (Lama guanicoe Müller), is a South American native ungulate widely distributed in Patagonia, which in the island of Tierra del Fuego (TF), extends its habitat into Nothofagus spp. forests. Within these forests, guanacos consume lenga (Nothofagus pumilio) leaves and twigs, and other understory species. The aim of this work was to determine: 1) the spring and summer diet of free ranging guanacos, and 2) which plants, grown in the forest understory, guanacos do prefer, or avoid, in these seasons of great forage abundance. Area of study: Tierra del Fuego (Argentina), on three representative areas which combined Nothofagus forests and adjacent meadows (vegas). Material and Methods: uanacos’ diet was determined by comparing epidermal and non-epidermal plant fragments with micro-histological analyses of feces. The analysis was made from composite samples of fresh feces, collected at the seasons of maximum forage productivity (spring and summer). Main results: During spring, 48% of guanacos’ diet was composed of lenga leaves, 30% of grass-like species, 15% of grasses, and less than 7% of herbs, shrubs, and lichens. In summer, 40% of the diet was composed of grasses, 30% of lenga leaves, 25% of grass-like species and the rest corresponded to herbs, shrubs, and lichens. Within the forest understory, guanaco selected lenga leaves and twigs, grass species were consumed according to their availability (or sometimes rejected), while other herbs were not consumed at all. Research highlights: Guanacos’ consumption preference for lenga, even considering the high availability of other forages, could adversely affect forest regeneration.

Respuesta del microfitoplancton a la adición de nitrato y ácido silícico en fiordos de la Patagonia chilena

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Pamela Labbé-Ibáñez

2015-03-01

Full Text Available La Patagonia chilena está experimentando un aumento del uso del suelo y océano costero y el acelerado derretimiento de algunos glaciares, por lo que uno de los escenarios a futuro es que los fiordos adyacentes reciban cantidades variables de agua dulce y nutrientes inorgánicos. Se estudió la respuesta de ensambles de fitoplancton de los fiordos Reloncaví en invierno y Comau en primavera, a la adición de nitrato y ácido silícico en experimentos de microcosmos. Los ensambles fitoplanctónicos estudiados respondieron a la adición de nutrientes con incrementos en la abundancia celular biomasa autotrófica (clorofila-a y cambios en la composición específica, destacando el cambio de dominancia de especies de diatomeas pennadas a céntricas formadoras de cadenas. Estos resultados dan indicios acerca de los factores que afectan a las comunidades microalgales en un escenario de cambio climático e intervención antrópica de los fiordos de la Patagonia Norte.

Noble gas composition of subcontinental lithospheric mantle: An extensively degassed reservoir beneath Southern Patagonia

Science.gov (United States)

Jalowitzki, Tiago; Sumino, Hirochika; Conceição, Rommulo V.; Orihashi, Yuji; Nagao, Keisuke; Bertotto, Gustavo W.; Balbinot, Eduardo; Schilling, Manuel E.; Gervasoni, Fernanda

2016-09-01

Patagonia, in the Southern Andes, is one of the few locations where interactions between the oceanic and continental lithosphere can be studied due to subduction of an active spreading ridge beneath the continent. In order to characterize the noble gas composition of Patagonian subcontinental lithospheric mantle (SCLM), we present the first noble gas data alongside new lithophile (Sr-Nd-Pb) isotopic data for mantle xenoliths from Pali-Aike Volcanic Field and Gobernador Gregores, Southern Patagonia. Based on noble gas isotopic compositions, Pali-Aike mantle xenoliths represent intrinsic SCLM with higher (U + Th + K)/(3He, 22Ne, 36Ar) ratios than the mid-ocean ridge basalt (MORB) source. This reservoir shows slightly radiogenic helium (3He/4He = 6.84-6.90 RA), coupled with a strongly nucleogenic neon signature (mantle source 21Ne/22Ne = 0.085-0.094). The 40Ar/36Ar ratios vary from a near-atmospheric ratio of 510 up to 17700, with mantle source 40Ar/36Ar between 31100-6800+9400 and 54000-9600+14200. In addition, the 3He/22Ne ratios for the local SCLM endmember, at 12.03 ± 0.15 to 13.66 ± 0.37, are higher than depleted MORBs, at 3He/22Ne = 8.31-9.75. Although asthenospheric mantle upwelling through the Patagonian slab window would result in a MORB-like metasomatism after collision of the South Chile Ridge with the Chile trench ca. 14 Ma, this mantle reservoir could have remained unhomogenized after rapid passage and northward migration of the Chile Triple Junction. The mantle endmember xenon isotopic ratios of Pali-Aike mantle xenoliths, which is first defined for any SCLM-derived samples, show values indistinguishable from the MORB source (129Xe/132Xe =1.0833-0.0053+0.0216 and 136Xe/132Xe =0.3761-0.0034+0.0246). The noble gas component observed in Gobernador Gregores mantle xenoliths is characterized by isotopic compositions in the MORB range in terms of helium (3He/4He = 7.17-7.37 RA), but with slightly nucleogenic neon (mantle source 21Ne/22Ne = 0.065-0.079). We

The blue land planarian Caenoplana coerulea, an invader in Argentina La planaria terrestre azul Caenoplana coerulea, un invasor en Argentina

Directory of Open Access Journals (Sweden)

Lisandro Héctor Luis-Negrete

2011-03-01

Full Text Available The blue land planarian Caenoplana coerulea is reported from Argentina (Buenos Aires province. We found C. coerulea in the east central region of Argentina in anthropic environments. The specimens that we found have the characteristic of the species found in others regions; that is, a bluish dorsal surface with a yellow mid-dorsal stripe and eyes forming a single row around the anterior tip, clustered laterally. This is the first record of this species from the Neotropical Region, and together with Bipalium kewense are the only 2 species of exotic terrestrial planarians so far recorded in Argentina.La planaria terrestre azul Caenoplana coerulea se registra para el centro este de Argentina (provincia de Buenos Aires, en ambientes antropizados. Los ejemplares encontrados presentan las características de la especie registrada en otras regiones, con una superficie dorsal azulada y una hilera medio dorsal amarilla, y ojos formando una hilera alrededor del extremo anterior, agrupados lateralmente. Es la primera vez que se cita dicha especie en la Región Neotropical, y junto a Bipalium kewense son las únicas planarias terrestres exóticas registradas en Argentina.

de la sociedad argentina

Directory of Open Access Journals (Sweden)

Diego Galeano

2007-01-01

Full Text Available Este artículo trata sobre un período de la historia argentina en el cual la "mirada médica", a través de un grupo de prestigiosos intelectuales, se convirtió en una clave de interpretación de la sociedad argentina. El análisis gira en torno a la obra de uno de los médicos higienistas más influyentes, José María Ramos Mejía, deteniéndose especialmente en su libro más famoso: Las multitudes argentinas (1899. La hipótesis principal que recorre el texto es la siguiente: la medicalización de la sociedad, acentuada luego de las epidemias de cólera y fiebre amarilla de mediados del siglo XIX, ofreció a las elites públicas la posibilidad de construir dominios legítimos de intervención estatal. Intromisiones del Estado en la vida privada que, además de ser algo resistidas por la población, entraban en tensión con los principios teóricos del liberalismo que los propios miembros de la elite defendían.

Argentina

Energy Technology Data Exchange (ETDEWEB)

1999-09-01

This report presents a brief overview of the socio-economic, energy and environmental context in which climate change mitigation actions in Argentina shall be inserted. To that end, the dynamic of the Argentine economic development, its influence on the energy system and environmental impacts is summarised. From the environmental standpoint, emphasis shall only be made on the impact of economic development patterns and energy policies on GHG emission. (au) 73 refs.

Crisis cambiaria en Argentina

OpenAIRE

Féliz, Mariano

2009-01-01

El análisis de la articulación entre el proceso de valorización exitosa de capital y la tendencia a la desvalorización de las mercancías se aplica a una de las manifestaciones de la crisis argentina: la devaluación del peso. Se estudia la relación entre la determinación del tipo de cambio y la valorización del capital. Se discuten las tendencias concretas de la economía argentina en la década de 1990 y se muestra cómo la devaluación de 2001-2002 fue producto necesario del propio proceso de va...

Control of nuclear materials and materials in Argentina

International Nuclear Information System (INIS)

Arbor G, A.; Fernandes M, S.

1988-01-01

A general view about the safeguards activities in Argentina is presented. The national system of accounting for and control of nuclear materials is described. The safeguards agreement signed by Argentina are presented. (E.G.) [pt

Argentina to fully privatize state owned YPF

International Nuclear Information System (INIS)

Anon.

1992-01-01

Argentina's Congress has voted to fully privatize state petroleum company Yacimientos Petroliferos Fiscales (YPF), a move the government expects to net at least $8 billion. Despite some political opposition, the vote was 119-10 in favor, with one abstention and opposition party members refusing to participate in the vote. Argentina's President Carlos Menem had threatened to authorize YPF privatization by decree if there was no quorum for a vote. YPF is responsible for 40% of Argentina's oil production. The country h as been self-sufficient in crude since 1982. Current production is 563,472 b/d, and proved reserves of oil and gas are valued at $7 billion

Nueva especie de Planorbidae (Gastropoda: Basommatophora en la Patagonia chilena: Biomphalaria cristiani sp. nov. First record of Planorbidae (Mollusca: Basommatophora in Chilean Patagonia: Biomphalaria cristiani sp. nov.

Directory of Open Access Journals (Sweden)

Carmen Fuentealba

2012-11-01

Full Text Available En Chile la familia Planorbidae está representada por el género Biomphalaria Preston, 1910, compuesta por siete especies distribuidas desde Isluga hasta el río Puelo. De estas especies, solo B.peregrina, ampliamente distribuida en el neotrópico, y Biomphalaria aymara de Isluga, han sido reconocidas sobre la base de la morfología del sistema reproductor y la rádula, caracteres que fueron utilizados en el presente estudio para diferenciar a Biomphalaria cristiani como nueva especie del grupo y primer registro de la familia en la Patagonia chilena, ampliando su actual rango de distribución. Los caracteres que permiten la diagnosis de B. cristiani son el saco vaginal vestigial truncado, ausencia del desarrollo de los músculos suspensores del pene, vaina del pene corta en relación al prepucio, oviducto largo en relación al espermioducto y vaso deferente más delgado y largo que la vaina del pene, de tamano similar al prepucio. La localidad tipo de Biomphalaria cristiani sp. nov. es Laguna Cisnes (47°7'10.02"S, 72°27'40.65"W, región de Aysén.The family Planorbidae in Chile is represented by the genus Biomphalaria Preston, 1910, consisting of seven species distributed from Isluga to Puelo River. Of these species, only Biomphalaria peregrina widely distributed in the neotropical and Biomphalaria aymara from Isluga are recognized based on the morphology of the reproductive system and radula, characters that were used in the following study to differentiate Biomphalaria cristiani as a new species of this group and first record of the family in Chilean Patagonia, extending its current distribution range. The characters for the diagnosis of B. cristiani are: truncated vestigial vaginal pouch, lack of development of the penis retractor muscles, penis sheath shorter than the prepuce, oviduct longer than the spermiduct and vas deferens thinner and longer than the penis sheath, similar size to the prepuce. The type locality of B. cristiani nov. sp

Hess Deep Interactive Lab: Exploring the Structure and Formation of the Oceanic Crust through Hands-On Models and Online Tools

Science.gov (United States)

Kurtz, N.; Marks, N.; Cooper, S. K.

2014-12-01

Scientific ocean drilling through the International Ocean Discovery Program (IODP) has contributed extensively to our knowledge of Earth systems science. However, many of its methods and discoveries can seem abstract and complicated for students. Collaborations between scientists and educators/artists to create accurate yet engaging demonstrations and activities have been crucial to increasing understanding and stimulating interest in fascinating geological topics. One such collaboration, which came out of Expedition 345 to the Hess Deep Rift, resulted in an interactive lab to explore sampling rocks from the usually inacessible lower oceanic crust, offering an insight into the geological processes that form the structure of the Earth's crust. This Hess Deep Interactive Lab aims to explain several significant discoveries made by oceanic drilling utilizing images of actual thin sections and core samples recovered from IODP expeditions. . Participants can interact with a physical model to learn about the coring and drilling processes, and gain an understanding of seafloor structures. The collaboration of this lab developed as a need to explain fundamental notions of the ocean crust formed at fast-spreading ridges. A complementary interactive online lab can be accessed at www.joidesresolution.org for students to engage further with these concepts. This project explores the relationship between physical and on-line models to further understanding, including what we can learn from the pros and cons of each.

Etnobotánica, anatomía y caracterización físico-química del aceite esencial de Baccharis obovata Hook. et Arn. (Asteraceae: Astereae Ethnobotany, anatomy and physicochemical characterization of essential oil of Baccharis obovata Hook. et Arn. (Asteraceae: Astereae

Directory of Open Access Journals (Sweden)

Soledad Molares

2009-06-01

Full Text Available Baccharis obovata Hook. et Arn. es una especie aromática conocida como "wautro", y forma parte destacada de la herbolaria Mapuche de la Patagonia Argentina. Los objetivos fueron investigar la etnobotánica, la anatomía del vástago, y caracterizar físicoquímicamente el aceite esencial presente en el mismo. Se realizaron entrevistas a pobladores de dos comunidades Mapuches del noroeste de la Patagonia Argentina, y se colectó material vegetal para su observación al microscopio óptico y de barrido ambiental, como así también, para la hidrodestilación del aceite esencial. Los informantes indicaron que la planta es utilizada en forma consensuada para el tratamiento de alopecia, caspa, diversas dermatitis, y cefaleas. Las principales características de la hoja son: mesofilo isobilateral, estomas anomocíticos, tricomas glandulares pluricelulares, y cavidades esquizógenas secretoras de aceites esenciales. El tallo primario presenta tricomas y cavidades secretoras semejantes a los de las hojas, colénquima en las costillas, clorénquima en los valles interrumpido por espacios de aire, cilindro vascular continuo, endodermis uniseriada y por sectores biseriada, esclerénquima discontinuo, y cristales aciculares en células periféricas de médula. Las determinaciones físico-químicas que se aportan son rendimiento medio anual, tiempo óptimo de destilación, densidad relativa, rotación específica e índice de refracción. B. obovata es una especie cosmecéutica de interés, este trabajo contribuye a su conocimiento general, aportando información para futuras tareas de control de calidad y para su conservación biocultural.Baccharis obovata Hook. et Arn. is an aromatic species known as "wautro", and is an important part of the Mapuche herbolarium of Patagonia Argentina. The objectives were to investigate its ethnobotany and shoot anatomy, as well as to characterize physically and chemically its essential oil. Rural informant-interviews were

On the intrinsic spectrum of PKS 2155-304 from H.E.S.S. 2003 data

International Nuclear Information System (INIS)

Costamante, L.; Benbow, W.; Horns, D.; Reimer, A.; Reimer, O.

2005-01-01

In 2003, PKS 2155-304 has been significantly detected by H.E.S.S. at Very High Energies (VHE), with an average spectrum of Γ = 3.3. Due to absorption by the Extragalactic Background Light (EBL), the intrinsic spectrum is heavily modified both in shape and intensity. To correct for this effect, and locate the Inverse Compton (IC) peak of the Spectral Energy Distribution (SED), we used three EBL models (representatives of three different flux levels for the stellar peak component). The resulting TeV spectrum has a peak around 1 TeV for stellar peak fluxes above the Primack (2001) calculation, while the spectrum is steeper than Γ = 2 (thus locating the IC peak 19 (for historical SED fluxes and 2 hours variability timescale)

Argentina; Argentine

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-04-01

This economical study summarizes the energy situation of Argentina: energy institutions and policy, energy companies (oil, electricity, gas, coal), energy supplies (resources, power production, petroleum, natural gas), prices and tariffs, consumption, economical stakes and perspectives (investments, agreements, projects). Energy data for the 1971-1999 period are summarized in graphs and tables. (J.S.)

Measurements of atmospheric fallout in Argentina; Determinacion del fallout atmosferico en la Republica Argentina

Energy Technology Data Exchange (ETDEWEB)

Canoba, A C; Lopez, F O; Bruno, H A

1998-11-01

With the purpose of studying the radioactive fallout present in Argentina from atmospheric nuclear explosions tests that have been conducted recently, an environmental monitoring program, outside the influence of nuclear facilities of Argentina, was undertaken during 1996 and 1997. The levels of Cs-137 and Sr-90 were analysed in samples of air, deposited material (rainwater), milk, an average meal of a standard man and food. During this period, a total of 630 radiochemical analysis were performed on 325 samples of the different matrices described. The concentration levels of the radionuclides analysed in the different environmental matrices are presented and are compared with the values obtained in the environmental monitoring program done during the period 1960-1981. (author) 3 refs., 9 tabs. [Espanol] Con el proposito de estudiar la precipitacion radiactiva presente en la Republica Argentina, debido al ensayo de armas nucleares en la atmosfera realizadas en el pasado, se implemento el muestreo ambiental fuera de la zona de influencia de las instalaciones nucleares de la Argentina durante los anios 1996 y 1997. Se determinaron las concentraciones de cesio 137 y estroncio 90 en muestras de aire, deposito de material radiactivo (agua de lluvia), leche, dieta promedio de un individuo estandar y en alimentos varios. Se realizaron, durante el periodo mencionado, un total de 630 determinaciones radioquimicas sobre 325 muestras de las diferentes matrices mencionadas. Se presentan los niveles de concentracion de los radionucleidos analizados en las distintas matrices ambientales y se comparan los valores obtenidos en los monitoreos realizados durante el periodo 1960-1981. (autor)

Aportes de los "intermediarios culturales" en la conformación de los paisajes fronterizos del norte de la patagonia a fines del siglo XVIII

Directory of Open Access Journals (Sweden)

Laura Aylén Enrique

2012-12-01

Full Text Available A fines del siglo XVIII la Corona española envió expedicionarios a reconocer el norte de la Patagonia, un territorio dominado por grupos indígenas pero de importancia estratégica para los hispanocriollos. Los funcionarios del Virreinato del Río de la Plata que llevaron a cabo dichas exploraciones registraron sus impresiones en diarios de viaje que analizamos con el objetivo de examinar los modos en que el paisaje norpatagónico fue construido simbólicamente. Consideramos que dicho paisaje se constituyó en base a las luchas desplegadas tanto por hispanocriollos como por indígenas buscando dar sentido al territorio. Sostenemos que, en este contexto, los personajes que se desempeñaban como intérpretes ejercían un rol fundamental en la configuración del territorio, dada la ambigüedad de su posición de intermediarios en las relaciones interétnicas.By late eighteen century the Spanish Crown sent expedition to recognize north Patagonia, a territory dominated by indigenous groups but also of strategic importance to the Hispanic-Creole population. River Plate Viceroyalty officials in charge of the above-mentioned explorations registered their impressions in travel diaries that are thoroughly analyzed in order to discover the ways this landscape of north Patagonia was symbolically constructed. We think this mestizo landscape was the result of struggles maintained between Hispanic-Creoles and natives searching to convey meaning to the territory. Moreover, we state that in this context, the actors who served as interpreters developed a key role in the territorial configuration, given the ambiguity of their position as intermediaries of interethnic relations.

Lama guanicoe remains from the Chaco ecoregion (Córdoba, Argentina): An osteological approach to the characterization of a relict wild population.

Science.gov (United States)

Costa, Thiago; Barri, Fernando

2018-01-01

Guanacos (Lama guanicoe) are large ungulates that have been valued by human populations in South America since the Late Pleistocene. Even though they were very abundant until the end of the 19th century (before the high deforestation rate of the last decades), guanacos have nearly disappeared in the Gran Chaco ecoregion, with relicts and isolated populations surviving in some areas, such as the shrubland area near the saline depressions of Córdoba province, Argentina. In this report, we present the first data from a locally endangered guanaco wild population, through the study of skeletal remains recovered in La Providencia ranch. Our results showed that most of the elements belonged to adults aged between 36 and 96 months; sex evaluation showed similar numbers of males and females. Statistical analysis of the body size of modern samples from Córdoba demonstrated that guanacos from the Chaco had large dimensions and presented lower size variability than the modern and archaeological specimens in our database. Moreover, they exhibited dimensions similar to those of modern guanacos from Patagonia and San Juan, and to archaeological specimens from Ongamira and Cerro Colorado, although further genetic studies are needed to corroborate a possible phylogenetic relationship. Finally, we used archaeozoological techniques to provide a first characterization of a relict guanaco population from the Chaco ecoregion, demonstrating its value to the study of modern skeletal remains and species conservation biology.

Modelling Soil Carbon Content in South Patagonia and Evaluating Changes According to Climate, Vegetation, Desertification and Grazing

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Pablo Luis Peri

2018-02-01

Full Text Available In Southern Patagonia, a long-term monitoring network has been established to assess bio-indicators as an early warning of environmental changes due to climate change and human activities. Soil organic carbon (SOC content in rangelands provides a range of important ecosystem services and supports the capacity of the land to sustain plant and animal productivity. The objectives in this study were to model SOC (30 cm stocks at a regional scale using climatic, topographic and vegetation variables, and to establish a baseline that can be used as an indicator of rangeland condition. For modelling, we used a stepwise multiple regression to identify variables that explain SOC variation at the landscape scale. With the SOC model, we obtained a SOC map for the entire Santa Cruz province, where the variables derived from the multiple linear regression models were integrated into a geographic information system (GIS. SOC stock to 30 cm ranged from 1.38 to 32.63 kg C m−2. The fitted model explained 76.4% of SOC variation using as independent variables isothermality, precipitation seasonality and vegetation cover expressed as a normalized difference vegetation index. The SOC map discriminated in three categories (low, medium, high determined patterns among environmental and land use variables. For example, SOC decreased with desertification due to erosion processes. The understanding and mapping of SOC in Patagonia contributes as a bridge across main issues such as climate change, desertification and biodiversity conservation.

Presence of Arctotherium (Carnivora, Ursidae, Tremarctinae in a pre-cultural level of Baño Nuevo-1 cave (Central Patagonia, Chile

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López Mendoza, P.

2015-12-01

Full Text Available The description of an I3 assigned to Arctotherium sp. obtained from the Baño Nuevo-1 site (Central Patagonia, Chile is presented. The finding was recovered from Layer 5 and it is associated to Macrauchenia sp., Lama guanicoe, Felidae, Camelidae, Equidae and Mylodontidae, within a sterile deposit of cultural material, dated between ca. 13.500 and 11.200 BP. Despite the fact that it is only a single specimen, such finding extends the known distribution for the genus in Chile.Se presenta la descripción de un I3 asignado a Arctotherium sp. proveniente del sitio Baño Nuevo-1 (Patagonia Central, Chile. El hallazgo fue realizado en la Capa 5 y está asociado a restos de Macrauchenia sp., Lama guanicoe, Felidae, Camelidae, Equidae y Mylodontidae dentro de un depósito estéril de material cultural, datado entre los ca. 13.500 y 11.200 años AP. Aunque se trata de un único espécimen, amplía el rango de distribución conocido para este género en Chile.

The regulatory control of radioactive sources in Argentina

International Nuclear Information System (INIS)

Rojkind, Roberto Hector

1997-01-01

Argentina has been conducting nuclear activities for more than forty years, and as early as in 1956 established a Regulatory Authority. Procedures for compliance monitoring and enforcement have been in use in the regulatory control of radioactive sources, and regulatory standards and regulations had been set in Argentina, before the accident in Goiania. The conclusions drawn from that accident encouraged in Argentina the improvement of some regulatory procedures and helped to enhance the quality of the regulatory process. Therefore, the effectiveness of the control of spent radioactive sources has gradually increased, and enforcement actions to prevent radioactive sources ending up in the public domain improved. Some lessons learned in Argentina from the accident in Goiania and the main characteristics of an effective enforcement program helpful to prevent radiological accidents in industrial, medical, research and teaching uses of radioactive sources are presented. (author)

Stereo-scopy of γ-ray air showers with the H.E.S.S. telescopes: first images of the supernova remnants at TeV

International Nuclear Information System (INIS)

Lemoine-Goumard, Marianne

2006-05-01

The H.E.S.S. (High Energy Stereoscopic System) experiment in gamma-ray Astronomy consists of four imaging atmospheric Cherenkov telescopes devoted to the observation of the gamma-ray sky in the energy domain above 100 GeV and extending up to several tens of TeV. This thesis presents a new reconstruction method of gamma-ray induced air showers which takes full advantage of the stereo-scopy and of the fine-grain imaging of the H.E.S.S. cameras. This new method provides an angular resolution better than 0.1 angle, an energy resolution of about 15% at zenith and a very efficient hadronic rejection based on a cut on the lateral spread of the electromagnetic shower which does not depend on simulations. A new background subtraction method, well adapted to the study of extended sources, was also developed. No assumption, either on the distribution of gamma-rays in the field of view, or on the distribution of hadrons are necessary. It provides two sky maps obtained from a maximum likelihood fit: one for γ-rays and the other for hadrons. These two analysis methods were applied to the study of the shell-type supernova remnants RX J1713.7-3946 and RX J0852.0-4622 (Vela Junior), allowing for the first time to resolve their morphology in the gamma-ray domain. The study of these sources should answer the question: 'can shell-type supernova remnants accelerate cosmic-rays up to the knee (5 x 10 15 eV)?'. A morphological and spectral study of these sources combined with a comparison of a simple model of emission processes (from electrons and protons accelerated in supernova remnants) provides some constraints on the parameters of the leptonic process. Nevertheless, this scenario cannot be excluded. The different results obtained are discussed and compared with a third shell-type supernova remnant observed by H.E.S.S. but not detected: SN 1006. (author)

Inorganic mercury (Hg2+ uptake by different plankton fractions of Andean Patagonian lakes (Argentina

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Diéguez M.C.

2014-07-01

Full Text Available The species composition and the size structure of natural planktonic food webs may provide essential information to understand the fate of mercury and, in particular, the bioaccumulation pattern of Hg2+ in the water column of lake ecosystems. Heterotrophic and autotrophic picoplankton and phytoplankton are the most important entry points for Hg in aquatic ecosystems since they concentrate Hg2+ and MeHg from ambient water, making them available to planktonic consumers at higher trophic levels of lake food webs. In this investigation we studied the uptake of 197Hg2+ in natural plankton assemblages from four Andean lakes (Nahuel Huapi National Park, Patagonia, Argentina, comprised in the size fractions 0.2-2.7 μm (picoplankton, 0.2-20 μm (pico and nanoplankton and 20-50 μm (microplankton through experiments using Hg2+ labeled with 197Hg2+. The experimental results showed that the uptake of Hg2+ was highest in the smallest plankton fractions (0.2-2.7 μm and 0.2-20 μm compared to the larger fraction comprising microplankton (20-50 um. This pattern was consistent in all lakes, reinforcing the idea that among pelagic organisms, heterotrophic and autotrophic bacteria with the contribution of nanoflagellates and dinoflagellates constitute the main entry point of Hg2+ to the pelagic food web. Moreover, a significant direct relationship was found between the Hg2+ uptake and surface index of the planktonic fractions (SIf. Thus, the smaller planktonic fractions which bore the higher SI were the major contributors to the Hg2+ passing from the abiotic to the biotic pelagic compartments of these Andean lakes.

Primer registro de Vespula vulgaris (Hymenoptera: Vespidae en la Argentina First record of Vespula vulgaris (Hymenoptera: Vespidae in Argentina

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Maité Masciocchi

2010-12-01

Full Text Available Vespula vulgaris (Linnaeus es un véspido social nativo de la región Holártica. En este trabajo reportamos la primera detección de esta especie en Argentina. Obreras de esta avispa fueron capturadas cerca de la ciudad de San Carlos de Bariloche (Argentina en Febrero de 2010, mientras se tomaban muestras de otra avispa invasora, Vespula germanica (Fabricius o chaqueta amarilla, de morfología externa y hábitos similares a la anteriormente mencionada. Además, detallamos algunos caracteres de identificación y características biológicas.Vespula vulgaris (Linnaeus is a social vespid native to the Holarctic region. The first detection of this species in Argentina is here reported. Workers were captured close to San Carlos de Bariloche (Argentina during February 2010, while sampling for another successful invader, the German wasp or Yellowjacket, Vespula germanica (Fabricius. Both these wasp species are very similar morphologically and share a number of common habits. Also, some identification features and biological characters are here explained.

A window on stochastic processes and gamma-ray cosmology through spectral and temporal studies of AGN observed with H.E.S.S

International Nuclear Information System (INIS)

Biteau, J.

2013-01-01

Fifty years after the discovery that quasars are extragalactic sources, their bright cores (AGN) and the jets that some of them exhibit still have plenty of secrets to share, particularly through observations in the gamma-ray band. Above 100 GeV, Cherenkov telescopes such as H.E.S.S. have detected 50 AGN, mostly blazars, objects whose jets are pointed toward the observer. The detection of two faint ones, 1ES 1312-423 and SHBL J001355.9-185406, is described in this thesis. Their multiwavelength spectra are reproduced with a synchrotron self-Compton model. The γ rays emitted by blazars are partly absorbed by the extragalactic background light (EBL), the second most intense cosmological background, which carries the integrated history of star formation. The first detection of this absorption above 100 GeV is performed, enabling the measurement of the EBL peak-amplitude in the optical band at the 20% level. In addition to these spectral studies, the fast flux-variations of blazars are investigated using the outbursts of PKS 2155-304 seen by H.E.S.S.. The observation of a skewed flux distribution and of an R.M.S.-flux correlation are interpreted within a kinematic model, where the emission is a realization of a stochastic process. (author)

Unemployment Assistance and Transition to Employment in Argentina

NARCIS (Netherlands)

A. Iturriza (Ana); A.S. Bedi (Arjun Singh); R.A. Sparrow (Robert)

2007-01-01

textabstractIn 2001-02, Argentina experienced a wrenching economic crisis. Plan Jefes, implemented in May 2002, was Argentina's institutional response to the increases in unemployment and poverty triggered by the crisis. The program provided a social safety net and appears to have successfully

Tabaquismo durante el embarazo en Argentina y Uruguay Smoking during pregnancy in Argentina and Uruguay

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Fernando Althabe

2008-02-01

Full Text Available Argentina y Uruguay están entre los países con mayor proporción de mujeres jóvenes fumadoras. Se desconoce cuál es la proporción exacta de ellas que fuman durante el embarazo así como las características de las que dejan de fumar y las que continúan fumando durante el embarazo. Realizamos una encuesta administrada por un/a entrevistador/a a 1512 mujeres embarazadas de 18 años o mayores (796 en Argentina; 716 en Uruguay, que concurrían a control prenatal en hospitales públicos de grandes conglomerados urbanos. 44% de las mujeres en Argentina y 53% en Uruguay habían sido o eran fumadoras. Durante el embarazo, 11% de las mujeres en Argentina y 18% en Uruguay continuaron fumando. En ambos países, la proporción de mujeres que vive con fumadores, permite fumar en el hogar y regularmente o siempre se encuentra en lugares cerrados con personas que estén fumando fue 49%, 46% y 20% entre las mujeres que nunca fumaron, 67%, 60% y 32% entre las que dejaron, y 78%, 75% y 52% entre las que continuaron fumando respectivamente. El estudio confirma un importante problema de salud pública y documenta que la exposición ambiental persiste en subgrupos de mujeres, aun en aquéllas que dejaron de fumar. Es importante que el sector de salud pública provea acceso a programas efectivos para dejar de fumar durante el embarazo. Cualquier nueva intervención a desarrollar que intente tener un éxito al menos moderado y sostenible, debiera incluir componentes que actúen sobre el entorno fumador de la mujer embarazada que fuma.Argentina and Uruguay are among the countries in which a large proportion of young women smoke. The rate of smokers during pregnancy in both countries is not well known, and data on the characteristics of women who quit smoking during pregnancy compared to those who continue smoking are not available. We conducted a survey including 1512 pregnant women >18 years old (796 in Argentina; 716 in Uruguay, during antenatal visits in

The bloodsucking biting midges of Argentina (Diptera: Ceratopogonidae

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Gustavo R Spinelli

2005-04-01

Full Text Available A key is presented for the identification of the adults of 54 species of bloodsucking ceratopogonids, 51 of which are known inhabitants of Argentina, and Culicoides uruguayensis Ronderos, C. pifanoi Ortiz, and C. trilineatus Fox, which are known to occur in bordering Uruguay and Paraguay. Wing photographs are provided of females of the 45 species of Culicoides. Three new species of Culicoides Latreille from Northeastern Argentina are described and illustrated: C. austroparaensis Spinelli, C. bachmanni Spinelli, and C. williamsi Spinelli. The following six species are recorded for the first time from Argentina and/or bordering localities in Paraguay: Leptoconops brasiliensis (Lutz, C. gabaldoni Ortiz, C. ginesi Ortiz, C. pifanoi Ortiz, C. pseudocrescentis Tavares and Luna Dias, and C. trilineatus; and C. estevezae Ronderos and Spinelli is newly recorded from Misiones province of Argentina. C. lopesi Barretto is excluded from the Argentinean ceratopogonid fauna.

A 2D hydrodynamic-sedimentological model for gravel-bed rivers. Part I: theory and validation

OpenAIRE

Gabriel Kaless; Mario A. Lenzi; Luca Mao

2013-01-01

This paper presents a novel 2D-depth average model especially developed for gravel-bed rivers, named Lican-Leufú (Lican=pebble and Leufu=river, in Mapuche’s language, the native inhabitants of Central Patagonia, Argentina). The model consists of three components: a hydrodynamic, a sedimentological, and a morphological model. The flow of water is described by the depth-averaged Reynolds equations for unsteady, free-surface, shallow water flows. It includes the standard k-e model for turbulence...

Can the Trinidad and Tobago Defence Force be Used Successfully as an Instrument of Nation Building in Trinidad and Tobago

Science.gov (United States)

1994-06-03

nations face. Like Lundberg and Martin, they believe that humanitarian assistance, to needy nations, in the form of providing food, shelter , and clothing...there is the flat to rolling plateau of Patagonia which has many sheep ranches. To the west of Argentina is the Cordillera of the Andes and to the...constructing nesting islands and wildlife shelters .20 ’ Assistance was given to the Grazing Service by the CCC. Its members constructed springs and reservoirs in

Nuevas citas de Coleoptera acuáticos y Megaloptera para la provincia de Chubut (Argentina New records of aquatic Coleoptera and Megaloptera from Chubut province (Argentina

Directory of Open Access Journals (Sweden)

Miguel Archangelsky

2004-12-01

Full Text Available Se informa acerca de nuevos hallazgos de coleópteros acuáticos, de Dytiscidae, Gyrinidae, Hydrophilidae y Elmidae para la provincia de Chubut (Argentina. También se cita por primera vez a las Sialidae (Megaloptera, género Protosialis Weele, para la República Argentina.New records of aquatic Coleoptera, in the families Dytiscidae, Gyrinidae, Hydrophilidae and Elmidae, are reported for the Chubut province (Argentina. The Sialidae (Megaloptera, genus Protosialis Weele, is reported for the first time in Argentina.

Atlas de Tupinambis rufescens (Squamata: Teiidae. Anatomía externa, osteología y bibliografía

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Montero, Ricardo

2004-07-01

Full Text Available Los lagartos que en Argentina se conocen como "iguana roja" o "caraguay" pertenecen al género Tupinambis, uno de los saurios de mayor talla del continente; tienen importancia económica, tanto por su cuero como por su carne. Se reconocen seis especies actuales, que se distribuyen en América del Sur desde Colombia hasta el norte de la Patagonia, Argentina (Cei, 1993. Por su amplia distribución y abundancia son utilizados como animales de laboratorio por lo que es importante el conocimiento detallado de su anatomía. Es por ello que aquí presentamos en un Atlas fotográfico la morfología externa y osteología de Tupinambis rufescens.

Search for tiny or transient sources in the Galaxy's central regions with H.E.S.S. - Application to the study of supernova W49B's remnant region

International Nuclear Information System (INIS)

Brun, F.

2011-09-01

H.E.S.S. (High Energy Stereoscopic System) is an array of four very-high energy (VHE) gamma-ray telescopes located in Namibia. These telescopes use the atmospheric Cherenkov imaging technique to detect gamma-rays between 100 GeV and a few tens of TeV. The H.E.S.S. cameras, each composed of 960 photomultiplier tubes and a fast electronics, need an accurate calibration of the shower to electronic signal conversion. A spurious capacitive coupling between the photomultiplier tubes and the data acquisition system (the common modes) was revealed and corrected during this thesis, resulting in data of better quality. H.E.S.S. is ideally located to observe the inner regions of the Galactic plane. Hence, the Galactic Plane Survey has been one of the primary goal since the beginning of the array operation in 2004 and led to unveiling the diversity of the VHE gamma-ray sources. This thesis presents the search for VHE gamma-ray sources in the inner regions of the Galactic plane using the most sensitive semi-analytical model based analysis currently available. A search for transient sources was also performed for these regions using powerful methods based on the time difference between consecutive events. These methods have been precisely characterized by simulation and didn't lead to the detection of significant variable sources. The very-high energy gamma-ray emission from the W49 region and the supernova remnant W49B in particular has been revealed during this thesis. The analysis of this region and the implications of this discovery are described in detail in this manuscript. (author)

Horizontalidad, autogestión y protagonismo en Argentina

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Marina Sitrin

2010-02-01

Full Text Available Este artículo trata los movimientos sociales autónomos que surgieron después de la crisis económica y la posterior rebelión popular en Argentina en diciembre de 2001. Los movimientos autónomos en la Argentina, como tantos movimientos en el mundo de hoy, son movimientos basados en la creación de nuevas relaciones sociales y comunidades ahora, al mismo tiempo que proyectan nuevas sociedadesy las relaciones en y para el futuro. Son movimientos con una concepción diferente del tiempo y el espacio. Son movimientos queentienden lo individual y lo colectivo como vinculados entre sí. Hay mucho en común entre la experiencia en la Argentina y las prácticas eideas anarquistas. Eso no significa que los que están creando nuevas relaciones y comunidades en la Argentina sean anarquistas. Lo que este artículo intenta hacer es basarse en las experiencias de los movimientos sociales argentinos para iniciar una reflexión sobre lasprácticas e ideas que los anarquistas pueden prestar a los distintos movimientos y comunidades autónomas; y, a su vez, sobre lo que los movimientos autónomos en la Argentina puede dar a las ideas y prácticas anarquistas.

Paleoparasitological finding of eggs of nematodes in rodent coprolites dated at the early Holocene from the archaeological site Cerro Casa de Piedra 7, Santa Cruz, Argentina.

Science.gov (United States)

Sardella, N H; Fugassa, M H

2011-12-01

The aim of the present study was to examine the parasite remains present in rodent coprolites collected from the archaeological site Cerro Casa de Piedra 7 (CCP7), located in the Perito Moreno National Park (47°57'S, 72°05'W), Santa Cruz Province, Argentina. Eight coprolites obtained from the layer 17, dated at 10,620 ± 40 to 9,390 ± 40 yr B.P., were examined for parasites. Feces were processed whole, rehydrated, homogenized, subjected to spontaneous sedimentation, and examined via light microscopy. Eggs of parasites were measured and photographed. Seven of 8 coprolites possessed 199 eggs of 2, probably new, species of nematodes, including 43 eggs of Heteroxynema sp. Hall, 1916 (Cavioxyura sp. Quentin, 1975) (Oxyurida, Heteroxynematidae), and 156 eggs of Trichuris sp. Roederer, 1761 (Trichinellida, Trichuridae). Heteroxynema sp. is cited for the first time from ancient material worldwide. The finding of Trichuris spp. in both rodents and other host samples from the area under study is indicative of the stability of the biological and environmental conditions for this nematode genus to establish in the Patagonian Early Holocene. The rodent host was assigned to an unknown species of Caviomorpha (Hystricognathi) that lived during the Pleistocenic transition in Patagonia.

The regulatory control of radioactive sources in Argentina

Energy Technology Data Exchange (ETDEWEB)

Rojkind, Roberto Hector [Autoridade Regulatoria Nuclear, Buenos Aires (Argentina)

1997-12-31

Argentina has been conducting nuclear activities for more than forty years, and as early as in 1956 established a Regulatory Authority. Procedures for compliance monitoring and enforcement have been in use in the regulatory control of radioactive sources, and regulatory standards and regulations had been set in Argentina, before the accident in Goiania. The conclusions drawn from that accident encouraged in Argentina the improvement of some regulatory procedures and helped to enhance the quality of the regulatory process. Therefore, the effectiveness of the control of spent radioactive sources has gradually increased, and enforcement actions to prevent radioactive sources ending up in the public domain improved. Some lessons learned in Argentina from the accident in Goiania and the main characteristics of an effective enforcement program helpful to prevent radiological accidents in industrial, medical, research and teaching uses of radioactive sources are presented. (author) 9 refs; e-mail: rrojkind at sede.arn.gov.br

Control of gaseous emissions in central Costanera S.A. of Argentina; Control de emisiones gaseosas en central Costanera S. A. de Argentina

Energy Technology Data Exchange (ETDEWEB)

Brabenec, Edgardo [Unidad de Negocios Central Costanera, S. A., (Argentina)

1997-12-31

A description is presented of the equipment utilized at the Central Costanera, S.A. of Argentina, the requirements and the Environmental Management established for this Power Station, and the Standards and the resolutions and law instruments on Environmental issues. Also it is presented the Environmental Management plan of the Ente Nacional Regulador de Electricidad of Argentina as well as the controls and environmental corrective actions implemented at the Central Costanera, S.A. [Espanol] Se presenta una descripcion del equipo utilizado en la Central Costanera S.A. de Argentina, los requerimientos de gestion ambiental establecidos para esta central y las normas, resoluciones e instrumentos juridicos en materia ambiental. Se presenta ademas el plan de gestion ambiental del Ente Nacional Regulador de la Electricidad de Argentina asi como los controles y acciones correctivas ambientales implantadas en la Central Costanera S. A.

Control of gaseous emissions in central Costanera S.A. of Argentina; Control de emisiones gaseosas en central Costanera S. A. de Argentina

Energy Technology Data Exchange (ETDEWEB)

Brabenec, Edgardo [Unidad de Negocios Central Costanera, S. A., (Argentina)

1996-12-31

A description is presented of the equipment utilized at the Central Costanera, S.A. of Argentina, the requirements and the Environmental Management established for this Power Station, and the Standards and the resolutions and law instruments on Environmental issues. Also it is presented the Environmental Management plan of the Ente Nacional Regulador de Electricidad of Argentina as well as the controls and environmental corrective actions implemented at the Central Costanera, S.A. [Espanol] Se presenta una descripcion del equipo utilizado en la Central Costanera S.A. de Argentina, los requerimientos de gestion ambiental establecidos para esta central y las normas, resoluciones e instrumentos juridicos en materia ambiental. Se presenta ademas el plan de gestion ambiental del Ente Nacional Regulador de la Electricidad de Argentina asi como los controles y acciones correctivas ambientales implantadas en la Central Costanera S. A.

Prospect for Development of Open Access in Argentina

Science.gov (United States)

Miguel, Sandra; Bongiovani, Paola C.; Gomez, Nancy D.; Bueno-de-la-Fuente, Gema

2013-01-01

This perspective article presents an overview of the Open Access movement in Argentina, from a global and regional (Latin American) context. The article describes the evolution and current state of initiatives by examining two principal approaches to Open Access in Argentina: "golden" and "green roads". The article will then…

Influence of precipitation, landscape and hydrogeomorphic lake features on pelagic allochthonous indicators in two connected ultraoligotrophic lakes of North Patagonia

International Nuclear Information System (INIS)

Queimaliños, Claudia; Reissig, Mariana; Diéguez, María del Carmen; Arcagni, Marina; Ribeiro Guevara, Sergio; Campbell, Linda; Soto Cárdenas, Carolina; Rapacioli, Raúl

2012-01-01

We investigated the terrestrial influence on two chained deep ultraoligotrophic lakes of North Patagonia (Argentina) through the seasonal analysis of two pelagic allochthonous indicators: i) water color, as a proxy of allochthonous dissolved organic matter in lakes; and ii) the color to chlorophyll a ratio (Color:Chla), as an indicator of the relationship between allochthonous and autochthonous carbon pools. We also evaluated the potential transfer pathways of the allochthonous dissolved organic matter into the pelagic food webs of these deep lakes, including the natural zooplankton δ 13 C in the analysis. The dynamics of the allochthonous indicators were related to the precipitation regime, water level fluctuations, and hydrogeomorphic and catchment features of lakes Moreno East and Moreno West. The water color (absorbance at 440 nm) was extremely low ( −1 ) in both lakes regardless of the season. However, precipitation and snowmelt regimes drove the increase and decrease of water color, respectively. A significant positive relationship between the zooplankton bulk δ 13 C with the water color would suggest an input of allochthonous organic carbon into the pelagic consumers. The incorporation of the dissolved allochthonous material into higher trophic levels is likely favored by the bacterivorous behavior of planktonic organisms, mixotrophic flagellates and ciliates, which dominate the pelagic food webs of these Patagonian lakes. Morphometric aspects, mainly the higher water residence time, led to lower values of allochthony in Moreno East compared to Moreno West, probably accentuated by its upper position in the lake chain. Overall, our results suggest that these allochthonous signals can bring insight into the magnitude of the interaction between terrestrial environments and lake ecosystems, even in extremely clear and ultraoligotrophic systems, such as the Andean Patagonian lakes. - Highlights: ► Pelagic allochthonous indicators were detected in two

Estado actual de las investigaciones tafonómicas naturalistas en Punta Entrada y Monte León (patagonia meridional)

OpenAIRE

Muñoz, Sebastián Ramón; Cruz, Isabel

2017-01-01

Se presentan los resultados de las investigaciones tafonómicas naturalistas realizadas desde 2005 en la desembocadura del río Santa Cruz y el parque Nacional Monte león (Patagonia Meridional) dirigidas a conocer los modos en que tiene lugar el reciclado de restos de vertebrados en un mismo contexto ambiental, la estepa costera patagónica. Se resume el conocimiento generado sobre: el tiempo involucrado en la desarticulación de carcasas de vertebrados; los procesos y actores intervinientes y ...

Diel changes in metal concentrations in a geogenically acidic river: Rio Agrio, Argentina

Science.gov (United States)

Parker, Stephen R.; Gammons, Christopher H.; Pedrozo, Fernando L.; Wood, Scott A.

2008-12-01

Rio Agrio in Patagonia, Argentina is a geogenically acidic stream that derives its low-pH waters from condensation of acidic gases near its headwaters on the flanks of the active Copahue Volcano. This study reports the results of three diel (24-h) water samplings in three different pH regimes (3.2, 4.4 and 6.3) along the river. Changes in the concentration and speciation of Fe dominated the diel chemical changes at all three sites, although the timing and intensity of these cycles were different in each reach. At the two acidic sampling sites, total dissolved Fe and dissolved Fe(III) concentrations decreased during the day and increased at night, whereas dissolved Fe(II) showed the reverse pattern. These cycles are explained by Fe(III) photoreduction, as well as enhanced rates of precipitation of hydrous ferric oxide (HFO) during the warm afternoon hours. A strong correlation was observed between Fe(III) and As at the furthest upstream (pH 3.2) site, most likely due to co-precipitation of As with HFO. At the downstream (pH 6.3) location, Fe(II) concentrations increased at night, as did concentrations of rare earth elements and dissolved Al. Photoreduction does not appear to be an important process at pH 6.3, although it may be indirectly responsible for the observed diel cycle of Fe(II) due to advection of photochemically produced Fe(II) from acidic upstream waters. The results of this study of a naturally-acidic river are very similar to diel trends recently obtained from mining-impacted streams receiving acid rock drainage. The results are also used to explore the link between geochemistry and microbiology in acidic eco-systems. For example, Fe(III) photoreduction produces chemical potential energy (in the form of metastable Fe 2+) that helps support the bacterial community in this unique extreme environment.

Economy-wide impacts of biofuels in Argentina

International Nuclear Information System (INIS)

Timilsina, Govinda R.; Chisari, Omar O.; Romero, Carlos A.

2013-01-01

Argentina is one of the world's largest biodiesel producers and the largest exporter, using soybeans as feedstock. Using a computable general equilibrium model that explicitly represents the biofuel industry, this study carries out several simulations on two sets of issues: (i) international markets for biofuel and feedstock, such as an increase in prices of soybean, soybean oil, and biodiesel, and (ii) domestic policies related to biofuels, such as an introduction of biofuel mandates. Both sets of issues can have important consequences to the Argentinean economy. The simulations indicate that increases in international prices of biofuels and feedstocks would increase Argentina's gross domestic product and social welfare. Increases in international prices of ethanol and corn also can benefit Argentina, but to a lesser extent. The domestic mandates for biofuels, however, would cause small losses in economic output and social welfare because they divert part of biodiesel and feedstock from exports to lower-return domestic consumption. An increase in the export tax on either feedstock or biodiesel also would lead to a reduction in gross domestic product and social welfare, although government revenue would rise. - Highlights: ► Argentina is one of the largest biodiesel producer and exporter using soybeans. ► Economy-wide impacts are assessed using a CGE model for Argentina. ► Policies simulated are feedstock and biodiesel price change, and domestic mandates. ► Increases in international prices of biofuels and feedstock benefit the country. ► Domestic mandates for biofuels cause small losses in economic output

Application of the Hess-Brezowsky classification to the identification of weather patterns causing heavy winter rainfall in Brittany (France

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O. Planchon

2009-07-01

Full Text Available An accurate knowledge of the weather patterns causing winter rainfall over the Scorff watershed in western Brittany (W. France was developed prior to studies of the impact of the climate factor on land use management, and of the hydrological reponses to rain-producing weather patterns. These two studies are carried out in the context of the climate change. The identification of rainy air-circulation types was realized using the objective computational version of the 29-type Hess and Brezowsky Grosswetterlagen system of classifying European synoptic regimes, for the cold season (November-March of the 1958–2005 period at the reference weather station of Lorient, and 13 other stations located in western and southern Brittany, including a more detailed study for the wet 2000–2001 cold season for three reference stations of the Scorff watershed (Lorient, Plouay and Plouray. The precipitation proportion (including the days with rainfall ≥20 mm was calculated by major air-circulation type (GWT: see Appendix A and by individual air-circulation subtype (GWL: see Appendix A for the studied time-period. The most frequently occurrence of rainy days associated with westerly and southerly GWL confirmed well-known observations in western Europe and so justify the use of the Hess-Brezowsky classification in other areas outside Central Europe. The southern or south-western exposure of the watershed with a hilly inland area enhanced the heavy rainfall generated by the SW and S circulation types, and increased the difference between the rainfall amounts of coastal and inland stations during the wettest days.

Estudos de cetáceos no Oceano Atlântico Sul Ocidental e a falta de uma política de conservação e manejo no Brasil

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Maria Cristina Pinedo

1980-12-01

Full Text Available Studies on cetaceans at Argentina, Uruguay and Brazil can be divided in three periods. During the first one (1861-1963, studies of the Argentines Burmeister, Gallardo, Lahille and Marelli were done on dolphin and porpoise osteology, occasionally on whales, these wire followed by those of Miranda Ribeiro and Carvalho in Brazil. The second period (1969-1976 begins with the studies of the North Américan Gilmore (1969 in Patagonia. From this year on, numerous forcing expeditions came to Argentina and Uruguay, to study the right whale, Eubalaena australis behavior in Patagonia and the La Plata river dolphin. Pontoporia blainvillei biology at Punta del Diablo, Uruguay. These expeditions have contributed to a better knowledge of whales and dolphins, not only in South if not also, abroad. During thin period studies on bekzvior, bioacustics, population dynamics and bio-ecological studies ; began. Simultaneously it is observed that Latin Americm researches, specially those of Uruguay and Brazil, become interested ind doing cetological research on systematic aspects. The third period (1976- it is characterized by an increased effort on this field and also by a better exchange of information between the three S. W. Atlantic countries. In Brazil, during the last two years, a gret interest on the minke whale conservation problem has developed, not only at the public opinion, but also at the government level.

Tareas que realizan los bibliotecarios universitarios en Argentina

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Werner Agazzi

2011-08-01

Full Text Available El presente estudio es una investigación descriptiva que pretende conocer las tareas que realizan los bibliotecarios en las bibliotecas universitarias argentinas, abordando el tema desde la perspectiva de las competencias laborales y el actual perfil del bibliotecario universitario. Mediante la utilización de un cuestionario enviado a las direcciones de e-mail de bibliotecas universitarias argentinas se compilaron datos sobre las tareas que realizan los bibliotecarios en esas instituciones. A través de este proceso también se compilaron datos relacionados con las tareas de comunicación vía e-mail por parte de las bibliotecas universitarias argentinas.

Computing and Education in Argentina, Uruguay and Paraguay.

Science.gov (United States)

Sadowsky, Manuel

Although the report is specifically about Argentina, Uruguay and Paraguay, the considerations presented are valid for all of Latin America. In September, 1969, Argentina had approximately 200 electronic computers. The annual growth is estimated at 15-20% and the implementation of teleprocessing and time-sharing systems have made evident the…

O percurso de Sidarta e o problema da identidade um estudo transdisciplinar do romance de Hermann Hesse

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Luiz Eduardo da Silva e Souza

2008-06-01

Full Text Available O presente trabalho pretende discutir o problema da identidade pessoal com base na narrativa de Sidarta, de Hermann Hesse. A história de vida do personagem central do romance é analisada à luz da teoria junguiana do processo de individuação e contextualizada com base nas perspectivas histórico-etnológicas de Mircea Eliade e Joseph Campbell. Num momento posterior, o estudo integra também a perspectiva sociológica sobre o problema da auto-identidade desenvolvida por Anthony Giddens. Em última instância, o trabalho procura circunscrever a questão da auto-identidade apostando na possibilidade de uma abordagem transdisciplinar.

The nuclear research centre at Bariloche, Argentina

International Nuclear Information System (INIS)

Abriata, J.P.

2001-01-01

The nuclear research centre at Bariloche (CAB) is one of the four centres under the Atomic Energy Commission of Argentina (CNEA). The research programme of CAB addresses various issues like nuclear reactor development, nuclear fuel and fuel cycle, applications of radioisotopes and radiation, and waste management. There is also a basic nuclear science component. The human resource development in the areas of physics and nuclear engineering is done in an associated Balseiro Institute which has undergraduate and graduate programmes as well as doctoral and postdoctoral research. The Centre interacts well with the society and provides services in the nuclear area. It has a close interaction with the nuclear sector of Argentina as also with many international organisations. Regulatory control over the Centre is carried out by the Nuclear Regulatory Authority of Argentina. (author)

La evolución del espacio social y urbano en la capital de la Patagonia chilena. Punta Arenas

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Luis Inostroza Pino

2008-05-01

Razones del contexto mundial apoyadas por adecuadas decisiones a nivel local, son las que permitieron el desarrollo de la Patagonia y de la ciudad de Punta Arenas fundamentalmente hasta fines del siglo XIX. La iniciación del tráfico regular entre Europa y el Pacífico, con recalada obligada en la colonia, y las medidas de Puerto libre y de incentivo a la inmigración de colonos nacionales y extranjeros, influirán decisivamente en ese desarrollo. El modesto pueblo se transforma en un importante centro urbano.

Myiasis gastrointestinal humana por Eristalis tenax Gastrointestinal human myiasis for Eristalis tenax

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Marcelo Kun

1998-08-01

Full Text Available Son caracterizadas las myiasis registradas en Bariloche y establecidas las condiciones probables bajo las cuales se produjeron las infestaciones. Las larvas obtenidas a partir de heces de 2 pacientes fueron identificadas como Eristalis tenax (Diptera: Syrphidae de acuerdo a las claves de Hartley (1961 y Organización Panamericana de la Salud (1962. Estos 2 casos de myiasis gastrointestinal humana constituyen los primeros registrados en Bariloche (Patagonia, Argentina y sus características responden a las registradas para esta especie de Díptera en otras partes del mundo. La falta de control específico en el sistema domiciliario de suministro de agua ha sido la causa más probable de la infestación. Este registro extiende la distribución de E. tenax y de las myiasis gastrointestinales humanas en América del Sur hasta los 41º 03' S.Foram caracterizadas as miasis registradas em Bariloche (Patagonia, Argentina e estabelecidas as prováveis condições sob as quais são produzidas as infestações. As larvas obtidas a partir das fezes de dois pacientes foram identificadas como Eristalis tenax (Diptera: Syrphdae. Esses dois casos de miasis gastrointestinal humana foram os primeiros registrados em Bariloche, Argentina, e suas características respondem às registradas para esta espécie de Diptera em outras partes do mundo. A falta de controle específico no sistema domiciliário de abastecimento de água tem sido a causa mais provável de infestação. Este registro amplia a distribuição de E. tenax e das miasis gastrointestinais humanas em América do Sul até os 41º 03's.The myiasis observed in Bariloche are characterized and the probable conditions under which the infestations took place established. The larvae obtained from faeces of 2 patients were identified as Eristalis tenax (Diptera: Syrphidae according to Hartley (1961 and Organización Panamericana de la Salud keys (1962. These 2 cases of human gastrointestinal myiasis were the

The energy sector in Argentina

International Nuclear Information System (INIS)

2016-01-01

This article first outlines that Argentina produces an important part of its hydrocarbon consumption and comment various aspects of this production: hydrocarbons are at the heart of the Argentinian energetic model; conventional hydrocarbon reserves are however decreasing; the public operator remains the main actor even though the market is opened to multinational companies. The article then describes the crisis faced by this energetic model: the energy balance is now a burden; the increasing unbalance between production and consumption can be explained by supply-related as well as demand-related factors; authorities must intervene on hydrocarbon prices and subsidize the oil price on the domestic market. It appears that the future for hydrocarbons in Argentina relies on non-conventional hydrocarbons. Bio-fuels, a key sector of the Argentinian economy, are a matter of trade dispute with the EU and the USA. Apart from hydroelectricity (some new projects are planned), renewable energies are very few developed in Argentina. Appendices propose a graph of the distribution of energy consumption among the different sources, a map indicating locations of the main exploited hydrocarbon deposits, a presentation of mechanisms implemented to subsidize hydrocarbon production

Nuclear safeguards in Brazil and Argentina: 25 years of ABACC

Science.gov (United States)

Kassenova, Togzhan

2017-11-01

As possessors of advanced nuclear technology, Brazil and Argentina bear special responsibility for helping the international community and neighbors in their region feel confident that their nuclear programs are peaceful, secure, and safe. Over the past 25 years, the Brazilian-Argentine Agency for Accounting and Control of Nuclear Materials (ABACC) has played an indispensable role in strengthening such confidence by implementing nuclear safeguards in the two countries. Today, ABACC carries out safeguards inspections at a total of 76 nuclear facilities in Brazil and Argentina. This article describes how Brazil and Argentina view trends in the global nonproliferation regime and international nuclear safeguards, and explains how these trends relate to unique challenges and opportunities facing Brazil, Argentina, and ABACC.

Communications received from Argentina and Brazil

International Nuclear Information System (INIS)

1988-05-01

The document reproduces the Joint Declaration on Nuclear Policy signed by the Presidents of Argentina and Brazil on 30 November 1985, the Protocol on Nuclear Co-operation between Argentina and Brazil signed on 10 December 1986, the Joint Declaration on Nuclear Policy signed by the two Presidents on 10 December 1986, the Joint Declaration on Nuclear Policy signed by the two Presidents on 17 July 1987 and the Joint Declaration on Nuclear Policy (IPERO Declaration) signed by the two Presidents on 8 April 1988

Brasil, Argentina e América do Sul

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Paulo Nogueira Batista Jr.

2005-12-01

Full Text Available ESTE trabalho discute alguns aspectos da evolução econômica recente do Brasil, da Argentina e de outros países da América do Sul. Tendências econômicas e intelectuais perigosas, tais como a "globalização", o chamado Consenso de Washington, a dolarização e as negociações da Alca (Área de Livre Comércio das Américas, perderam ímpeto e a América do Sul está se movendo gradualmente na direção de um posicionamento mais independente na condução das suas política econômicas e internacionais. As mudanças foram muito mais significativas na Argentina do que no Brasil e isso se tornou fonte de alguma tensão entre os dois principais países sul-americanos. Não obstante, uma aliança estratégica entre Argentina e Brasil continua sendo a pedra angular da integração da América do Sul.THIS PAPER discusses some aspects of the recent economic evolution of Brazil, Argentina and other South American countries. Dangerous economic and intellectual trends, such as "globalization", the so-called Washington Consensus, dollarization, and FTAA (Free Trade Area of the Americas negotiations, have lost momentum and South America is moving gradually towards a more independent stance in the conduct of its economic and foreign policies. Changes have been much more significant in Argentina than in Brazil and this has become a source of some tension between the two major South American countries. Nevertheless, a strategic alliance between Argentina and Brazil remains the corner stone of South American integration.

A Maastrichtian microbial reef and associated limestones in the Roca Formation of Patagonia (Neuquén Province, Argentina

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W. Kiessling

2006-08-01

Full Text Available We describe a small microbial reef and associated limestones occurring in a Maastrichtian transgressive succession of mixed carbonate-siliciclastic lithologies at Sierra Huantraico near Chos Malal (Neuquén, Argentina. Strontium isotope data suggest that the reef is of earliest Maastrichtian age. The small reef (0.8 m thick, 2 m wide is mostly composed of peloidal bindstone, dense stromatolite-cement crusts and thrombolite. Except for some ostracods, no metazoan fossils were found in the reef structure, although the majority of peloids are fecal pellets, probably of larger crustaceans. Small foraminifers with calcite tests and probable green algae have also been noted. Sedimentological data and fossils within and immediately above the reef suggest that the reef was formed in a transgressive systems tract under freshwater to brackish-water conditions. Limestones above the reef are serpulid-bryozoan packstones and intraclast-ooid grainstones. These limestones yield a mixture of typical non-tropical (common serpulids and bryozoans and typical tropical aspects (common dasycladaceans and ooids. This mosaic is explained by salinity fluctuations, which in our case dominate over temperature in determining the grain associations. Wir beschreiben ein kleines mikrobielles Riff, das in der Sierra Hunatraico (Neuquén, Argentinien in einer transgressiven, gemischt siliziklastisch-kalkigen Abfolge gefunden wurde. Nach Strontiumisotopen-Datierung ist das Riff in das unterste Maastrichtium zu stellen. Das kleine Riff (0,8 m Mächtigkeit, 2 m Breite besteht überwiegend aus peloidalem Bindstone, dichten Stromatolith-Zement-Krusten und Thrombolith. Mit Ausnahme von Ostrakoden konnten keine Metazoen in der Riffstruktur nachgewiesen werden, obwohl die Mehrzahl der Peloide als Kotpillen zu interpretieren sind, die vermutlich auf größere Krebse zurückgehen. Kleine Foraminiferen und mögliche Grünalgen sind die einzigen zusätzlich nachweisbaren Eukaryoten

LAS ESPECIES DE MUHLENBERGIA (POACEAE: CHLORIDOIDEAE DE ARGENTINA

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Peterson Paul

2011-06-01

Full Text Available Se presenta un estudio taxonómico de las especies nativas argentinas del géneroMuhlenbergia, basado en el análisis de los especímenes depositados en 48 herbarios.Se analizan diversos aspectos relativos a la clasifi cación, la nomenclatura y lavariación morfológica de los caracteres. Muhlenbergia está representado enArgentina por 18 especies nativas. Se proporcionan claves para reconocer lasespecies presentes en el país, así como también descripciones de éstas, sinónimos,ilustraciones, distribución geográfica y algunos comentarios morfológicos yecológicos. Muhlenbergia breviaristata (Hack. Parodi y Muhlenbergia holwayorumHitchc., se reducen como sinónimos del híbrido Muhlenbergia angustata (J. PreslKunth × M. rigida (Kunth Kunth. Muhlenbergia diversiglumis Trin. se cita porprimera vez para la Argentina. Por otra parte, las especies Muhlenbergia tenella(Kunth Trin. y Muhlenbergia tenuissima (J. Presl Kunth se excluyen de la fl orade Argentina.

Late Pleistocene and Holocene landscape formation in a gully catchment area in Northern Hesse, Germany

DEFF Research Database (Denmark)

Döhler, Susanne; Damm, Bodo; Terhorst, Birgit

2015-01-01

the differentiation between Pleistocene and Holocene landforms. Radiocarbon and optically stimulated luminescence dating are applied to add numerical data to the relative ages of the sediments and landforms. The gully channels are oriented along Pleistocene depressions that are built up of periglacial cover beds...... and intercalated reworked loess. As the gully channels cut through the periglacial cover beds, especially the upper layer, the gully system is of Holocene age. At least two phases of gully erosion are identified in the alluvial fan sediments. The initial gully erosion is dated to the time span between the Late......Permanent gully channels under forest are common geomorphological features in Central European low mountain areas. In the Rehgraben/Fuchslöchergraben gully catchment in Northern Hesse, Germany the Late Pleistocene landscape formation is reconstructed based on periglacial cover beds. In addition...

Paleomagnetism of Jurassic and Cretaceous rocks in central Patagonia: a key to constrain the timing of rotations during the breakup of southwestern Gondwana?

Science.gov (United States)

Geuna, Silvana E.; Somoza, Rubén; Vizán, Haroldo; Figari, Eduardo G.; Rinaldi, Carlos A.

2000-08-01

A paleomagnetic study in Jurassic and Cretaceous rocks from the Cañadón Asfalto basin, central Patagonia, indicates the occurrence of about 25-30° clockwise rotation in Upper Jurassic-lowermost Cretaceous rocks, whereas the overlying mid-Cretaceous rocks do not show evidence of rotation. This constrains the tectonic rotation to be related to a major regional unconformity in Patagonia, which in turn seems to be close in time with the early opening of the South Atlantic Ocean. The sense and probably the timing of this rotation are similar to those of other paleomagnetically detected rotations in different areas of southwestern Gondwana, suggesting a possible relationship between these and major tectonic processes related with fragmentation of the supercontinent. On the other hand, the mid-Cretaceous rocks in the region yield a paleopole located at Lat. 87° South, Long. 159° East, A95=3.8°. This pole position is consistent with coeval high-quality paleopoles of other plates when transferred to South American coordinates, implying it is an accurate determination of the Aptian (circa 116 Ma) geomagnetic field in South America.

Biodiversity information system of the national parks administration of Argentina

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Leonidas Lizarraga

2014-06-01

Full Text Available Introduction The Biodiversity Information System (BIS of the National Parks Administration of Argentina (NPA was launched in 2002, with the support of the Global Environmental Fund (GEF through the Biodiversity Conservation Project in Argentina. The BIS consists of a set of thematic databases and Geographic Information System (GIS set to support management decisions, and to provide information to the general public on the national protected areas of Argentina. Currently, the BIS-NPA progr...

Update on women in physics in Argentina

Science.gov (United States)

Brudny, Vera; Lagorio, Cecilia; Frechero, Marisa; Tamarit, Francisco

2013-03-01

Data collected 10 years ago in Argentina concluded that women in physics were underrepresented in many instances and that a "crystal ceiling" was firmly in place. We have collected updated data for several indicators and compared them with those obtained 10 years ago. Although there is not a clear conclusion to be drawn from this comparison, we try to explain the results within the framework of the changes in scientific policies in Argentina.

Transnational Crime Fictions and Argentina's Criminal State

OpenAIRE

Caballero, Juan

2013-01-01

My dissertation, titled "Transnational Crime Fictions and Argentina's Criminal State," proposes a new understanding of the dictatorship novels of Ricardo Piglia, Juan José Saer, and Manuel Puig grounded in their shared appropriation from popular crime fiction. Across the 1940's, 50's, and 60's, a wide range of popular crime fiction was translated, written, theorized, printed and reprinted in Argentina, and these popular genres grew steadily in readership, visibility, and cultural legitimacy....

China, Argentina agree to further strategic ties

Institute of Scientific and Technical Information of China (English)

2011-01-01

According to Xinhua,China and Argentina have agreed to further enhance mutual trust and their strategic partnership as the two emerging economies are playing an increasingly important role in the world arena.“China will work with Argentina to strengthen strategic mutual trust,expand cooperation and coordination within multilateral frameworks in order to promote bilateral ties and benefit the two peoples,” Vice President Xi Jinping told Argentine Foreign Minister Hector Timerman on September 9.

All projects related to Argentina | Page 7 | IDRC - International ...

International Development Research Centre (IDRC) Digital Library (Canada)

Region: Americas, Argentina, South America. Program: Climate Change. Total Funding: CA$ 995,000.00. Youth Smoking in Stressed Environments : Determinants and Resiliency (Argentina, Colombia, Palestine). Project. Numerous studies have shown that the earlier an individual starts smoking, the harder it is to give it up.

Crecimiento anual de cuatro especies arbóreas con yemas desnudas nativas de los bosques templados húmedos de Patagonia

OpenAIRE

Sosa, Claudia M; Puntieri, Javier G

2016-01-01

Las especies vegetales que habitan en regiones con bajo nivel de estacionalidad en el clima suelen presentar rasgos morfo-arquitecturales que ocurren con menor frecuencia en especies de regiones con clima estacional. El objetivo de este estudio fue evaluar el crecimiento primario en vivero de cuatro especies leñosas típicas de los bosques templados húmedos de Patagonia, conocidos como selva valdiviana, donde el grado de estacionalidad es menos marcado que en otros bosques patagónicos. Las esp...

Nuclear Energy Stakeholders in Argentina

International Nuclear Information System (INIS)

Gadano, Julian

2017-01-01

Mr Gadano, Undersecretary for Nuclear Energy, Argentina spoke from the perspective of a country looking forward to becoming a member of the NEA. He reviewed the place of nuclear energy in his country's energy mix and called attention to its role in positively addressing the global challenges of climate change and energy security. Mr Gadano also described the federal system which governs Argentina. Drawing on his expertise as a lawmaker and nuclear regulator but also as an academic sociologist, he stressed that reaching agreement on siting initiatives for example requires a sustainable relation with stakeholders, including regional governments. This is important because in the end, 'the best project is the one you can finish'

Argentina set for privatization

International Nuclear Information System (INIS)

Chynoweth, E.

1992-01-01

Buyers are lining up for Argentina's two big state-controlled petrochemical groups, Buenos Aires-based Petroquimica General Mosconi (PGM) and Petroquimica Bahia Blance (PBB). However, feedstock supply contracts with government-owned oil group Yacientos Petroliferos Fiscales (YPG) and gas group Gas del Estado hold the key to both sales. Shell Compania Argentina Petroleo SA (CAPSA), Perez Companc, and Global Petroleum have already bought PGM tender documentation. Shell says it will bid for PGM if the feedstock contract with YPF is acceptable. In addition to price and volume, Shell says the length is critical; it wants a 15-year deal, but would settle for 11. YPF initially sought a five-year contract. PGM, which produces 300,000 m.t./year of aromatics, plus oxo alcohols, methanol, and methyl tert-butyl ether, has sales of $150 million/year

Miocene block uplift and basin formation in the Patagonian foreland: The Gastre Basin, Argentina

Science.gov (United States)

Bilmes, A.; D'Elia, L.; Franzese, J. R.; Veiga, G. D.; Hernández, M.

2013-08-01

The intraplate fault-block mountains and intermontane deposits of the Gastre Basin, which are recorded more than 550 km east of the Andean trench in central Patagonia, Argentina, are analyzed. The Gastre Basin is one of the largest Patagonian intermontane basins, limited by uplifted blocks strongly oblique to the Andean chain. It was originated by reverse faulting and inversion of pre-existing normal faults associated with a Mesozoic rift basin and defined by older crustal heterogeneities. The deformational event occurred during the middle Miocene, related to a short contractional episode (16.1-14.86 Ma), probably in response to an eastward migration of the Andean fold and thrust belt. During Pliocene to Quaternary times, neither younger fault-block uplifts nor reconfigurations of the basin occurred. Similarities between the study area and other parts of the Patagonian foreland - such as the presence of Miocene reverse or inversion tectonics, as well as the accommodation of the Miocene sedimentary successions - suggest that the Gastre Basin is part of a major late early to middle Miocene broken foreland system (i.e. the Patagonian broken foreland) that exhumed discrete fault-block mountains and generated contemporary basins along more than 950 km parallel to the Andean trench (i.e. between 40°00' and 48°00' south latitude). Based on recent studies on the southern Andean Margin, this continental-scale contractional episode may be the result of a flat-slab subduction segment. Nevertheless, such a hypothesis is very difficult to support when analyzing such a large flat subduction segment along the entire Patagonian trench. This suggests the need to consider alternative flat-slab trigger mechanisms or other factors in the generation of broken foreland systems.

Factors related to the attraction of flies at a biosolids composting facility (Bariloche, Argentina)

International Nuclear Information System (INIS)

Laos, F.; Semenas, L.; Labud, V.

2004-01-01

The composting process is used to treat biosolids from the Wastewater Treatment Plant of Bariloche (NW Patagonia, Argentina). Since 1998, an odourless, innocuous and stable organic amendment has been produced at the Biosolids Composting Plant of Bariloche. However, volatile compounds produced during this process, attract different vectors, mainly insects belonging to the Order Diptera, particularly in summer. To evaluate factors associated with the attraction of Diptera to composting windrows, volatile compounds, wind velocity, ambient and windrow temperatures were measured and their relationships with the taxa of flies found were determined. Sampling was conducted several months on newly formed windrows during 3 weeks of the thermophilic composting period. Composite samples from each windrow were taken on the first day of each sampling week, from November 1999 to March 2000 to analyze volatile compounds using an 'electronic nose'. Windrow and ambient temperatures and wind velocity were recorded on three consecutive days of each week, from January to March 2000; also the capture of flies was performed in this period. A weekly mean value was calculated for each environmental variable. Canonical Correspondence Analysis was employed to determine relationships between taxa of flies and the studied factors. The electronic nose discriminated among odours emitted, differentiating windrows by the bulking agent employed and by week of the thermophilic composting period. Ambient temperatures increased slightly during the sampling weeks; the highest values of wind velocity were registered during the second sampling week while windrow temperatures were sustained approximately 60 degree sign C. Canonical Correspondence Analysis showed that attraction of flies to composting windrows was related to minimum and maximum ambient temperatures and volatile compounds for Muscina stabulans, Fannia sp. and Acaliptratae and to wind velocity for Ophyra sp., Sarcophaga sp., Cochliomyia

Hydroclimatic conditions trigger record harmful algal bloom in western Patagonia (summer 2016).

Science.gov (United States)

León-Muñoz, Jorge; Urbina, Mauricio A; Garreaud, René; Iriarte, José Luis

2018-01-22

A harmful algal bloom (HAB) of the raphidophyta alga Pseudochattonella cf. verruculosa during the 2016 austral summer (February-March) killed nearly 12% of the Chilean salmon production, causing the worst mass mortality of fish and shellfish ever recorded in the coastal waters of western Patagonia. The HAB coincided with a strong El Niño event and the positive phase of the Southern Annular Mode that altered the atmospheric circulation in southern South America and the adjacent Pacific Ocean. This led to very dry conditions and higher than normal solar radiation reaching the surface. Using time series of atmospheric, hydrologic and oceanographic data we show here that an increase in surface water temperature and reduced freshwater input resulted in a weakening of the vertical stratification in the fjords and sounds of this region. This allowed the advection of more saline and nutrient-rich waters, ultimately resulting in an active harmful algal bloom in coastal southern Chile.

Ethical and Civic Education. Difficulties during the Curricular Reform in Argentine Patagonia

Directory of Open Access Journals (Sweden)

Isabelino Siede

2015-04-01

Full Text Available DOI: http://dx.doi.org/10.17227/01234870.41folios51.68 What type of ethical and civic education is effectively provided at school? This article analyzes the curricular prescriptions of Ethical and Citizenship Education in primary schools of the Argentine Patagonia, as well as its relations and contradictions with the school practices of moral education It inquires the process of definition of the area in the context of the Educational Reform in the 90s. Also, it pursuits to remake the way it was incorporated in the provincial curriculum design. Throughout focus groups and interviews to teachers from different public and private schools of three towns from de north of Santa Cruz, we analyze the descriptions and expectative of the teachers about their teaching practice in the moral area, as well as the possible causes of the differences and the contradictions between the policies of the curricular statement and educational proposals offered at school.

Una vuelta a la “casa bonita”. Un bricolage interpretativo de las fuentes documentales sobre los rituales de menarquía de los pueblos originarios de la Patagonia argentina (Siglos XIX y XX

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Graciela Hernández

2015-12-01

Full Text Available El principal objetivo de este trabajo es proponer un nuevo análisis del texto del británico Georges Musters, de su descripción de una ceremonia de menarquía (a la que denominó “casa bonita” observada entre tehuelches de la Patagonia en 1869, para contextualizarla históricamente y desde una perspectiva de género.Desde la metodología cualitativa hemos armado un bricolage que se expresa en un recorrido articulado por una genealogía de fuentes documentales del siglo XIX, por testimonios producidos en trabajos antropológicos y lingüísticos en la segunda mitad del siglo XX, y por registros etnográficos de nuestros trabajos en historia oral que focalizan en  rituales para propiciar el hilado.La triangulación de fuentes de los documentos seleccionados nos lleva a pensar en la hipótesis que en las ceremonias de primera menstruación, del siglo XIX en adelante, se propiciaba el apego al hilado y tejido,  en sociedades que también  ritualizaron toda la esfera del trabajo textil.

The other immigration to Argentina: the case of Adolf Eichmann

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Christian Cwik

2014-01-01

Full Text Available Adolf Eichmann llegó a la Argentina como otros 500 Nazis forajidos a través de una red de traficantes ilegales de migrantes entre 1945 y 1955. Esta red fue el resuldado del interés de la República de Argentina, la Cruz Roja, la Caritas y el Vaticano por un lado y por el otro los delincuentes. Eichmann la cara de la ‘banalidad del mal’, como Hannah Arendt escribió en su libro “Eichmann en Jerusalén: un estudio sobre la banalidad del mal”(2ª. edición, traducción de Carlos Ribalta, Barcelona, Lumen, 1999 tuvo bastantes problemas para integrarse en la sociedad argentina y por ende, fracasó. Adolf Eichmann nacido en 1906 en Solingen/Alemania personificó un caractér típico de la sociedad en la posguerra austriaca-alemana, lo que hizo que fracasara en su vida laboral varias veces durante los veintes y los inicios de los treinta del siglo XX.Palabras Clave: Adolf Eichmann;  Holocausto; Tráfico Ilegal de Migrantes; Inmigración en Argentina; Peronismo; Tribunales Internacionales. La otra inmigración a Argentina: El caso de Adolf EichmannAbstractAdolf Eichmann arrived to Argentina along with other 500 runaway Nazis thorugh a smuggling network between 1945 and 1955. This network was the result of the interest shown by the The Republic of Argentina, the Red Cross, Caritas and the Vatican in one hand; in the other, the criminals of war. Eichmann, the face of Hanna Arendt’s t “Banality of Evil” had numerous troubles to integrate to argentinian society, failing as a result.Adolf Eichmann, born in 1906 in Solingen, Germany, personified a typical Austrian-german postwar character, a fact that conduced to his laboral failure in the twentys and early thirties of the twentieth century.Keywords:Adolf Eichmann; Holocaust; Nazi Criminals; Trafficking of migrants; Post War Period; Immigration to Argentina; Peronism; Mossad; International Tribunal. 

Population structure and reticulate evolution of Saccharomyces eubayanus and its lager-brewing hybrids.

Science.gov (United States)

Peris, David; Sylvester, Kayla; Libkind, Diego; Gonçalves, Paula; Sampaio, José Paulo; Alexander, William G; Hittinger, Chris Todd

2014-04-01

Reticulate evolution can be a major driver of diversification into new niches, especially in disturbed habitats and at the edges of ranges. Industrial fermentation strains of yeast provide a window into these processes, but progress has been hampered by a limited understanding of the natural diversity and distribution of Saccharomyces species and populations. For example, lager beer is brewed with Saccharomyces pastorianus, an alloploid hybrid of S. cerevisiae and S. eubayanus, a species only recently discovered in Patagonia, Argentina. Here, we report that genetically diverse strains of S. eubayanus are readily isolated from Patagonia, demonstrating that the species is well established there. Analyses of multilocus sequence data strongly suggest that there are two diverse and highly differentiated Patagonian populations. The low nucleotide diversity found in the S. eubayanus moiety of hybrid European brewing strains suggests that their alleles were drawn from a small subpopulation that is closely related to one of the Patagonian populations. For the first time, we also report the rare isolation of S. eubayanus outside Patagonia, in Wisconsin, USA. In contrast to the clear population differentiation in Patagonia, the North American strains represent a recent and possibly transient admixture of the two Patagonian populations. These complex and varied reticulation events are not adequately captured by conventional phylogenetic methods and required analyses of Bayesian concordance factors and phylogenetic networks to accurately summarize and interpret. These findings show how genetically diverse eukaryotic microbes can produce rare but economically important hybrids with low genetic diversity when they migrate from their natural ecological context. © 2014 John Wiley & Sons Ltd.

El IDRC en Argentina

International Development Research Centre (IDRC) Digital Library (Canada)

comercio capaces de sostener el crecimiento y reducir la pobreza. ... Rosario, en Argentina, se ha convertido en un ejemplo internacional para la agricultura urbana gracias a la ... para evaluar los riesgos y beneficios de esta tecnología para ...

Activities with Argentina

International Nuclear Information System (INIS)

1999-01-01

In 1989, the US Department of Energy (DOE) responded to the need to redirect resources from weapons production to environmental restoration and waste management by establishing the Office of Environmental Management (EM) and delegated to this office the responsibility of cleaning up the US nuclear weapons complex. Now in its eight year, EM's mission has three central facets: (1) to assess, remediate, and monitor contaminated sites and facilities; (2) to store, treat, and dispose of waste from past and current operations; and (3) to develop and implement innovative technologies for environmental cleanup. To this end, EM has established domestic and international cooperative technology development programs, including one with the Republic of Argentina. Cooperating with Argentine scientific institutes and industries meets US cleanup objectives by: (1) identifying and accessing Argentine EM-related technologies, thereby leveraging investments and providing cost-savings; (2) improving access to technical information, scientific expertise, and technologies applicable to EM needs; and (3) fostering the development of innovative environmental technologies by increasing US private sector opportunities in Argentina in EM-related areas

«Hay que argentinizar la Patagonia». Miradas sobre la Nación y la Ciudadanía en tiempos de cambio (1916-1930

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Ruffini, Martha

2011-12-01

Full Text Available The Goverment of Civic Radical Union (1916-1930 encourage politicals and socials transformations, that for the National territories could implyed a modification on its marginal politic. The expressions of the leadership supported this perception, but the concepts of Nation and citizenship were redefined as considering the Patagonia a place to argentinized. The argentinization was introduced as priority ,because of rural worker conflictivity,determinating the extension from politic rights to orders validity, security and social control.

El gobierno de la Unión Cívica Radical (1916-1930 alentó transformaciones políticas y sociales que para los Territorios Nacionales podían implicar la modificación de su marginalidad política. Las expresiones de la dirigencia avalaron esta percepción pero los conceptos de Nación y Ciudadanía fueron resignificados al pensar la Patagonia como espacio a «argentinizar». La argentinización del sur se presentó como prioridad debido a la conflictividad obrera-rural, condicionando la ampliación de los derechos políticos a la vigencia del orden, la seguridad y el control social.

Primer registro paleoparasitológico de Trichuris SP (nematoda, capilariidae en muestras asociadas a restos humanos del Holoceno tardío de Patagonia septentrional

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Fugassa, Martín H.

2009-01-01

Full Text Available En el marco de los estudios paleoepidemiológicos que se realizan en restos arqueológicos asignados a poblaciones de cazadores-recolectores de Patagonia, este trabajo presenta información novedosa acerca de la presencia de parásitos en muestras de sedimento de las cavidades pélvicas correspondientes a individuos que habitaron la costa norte de Patagonia durante el Holoceno Tardío. Fueron analizados 3 casos de diferente cronología y en dos de ellos, los de menor antigüedad relativa, los resultados fueron positivos para la presencia de Trichuris trichiura. Es interesante mencionar al respecto que para el período que involucra a los dos casos positivos, la información arqueológica registra un proceso de intensificación en el que se explota una mayor diversidad de fauna y se incrementan los artefactos de molienda en los sitios. Entre las posibles causas propuestas para este proceso se encuentran el aumento demográfico y/o el nucleamiento poblacional en espacios favorables que comienzan a saturarse, hecho consistente con la evidencia cultural obtenida al momento y con la presencia de Trichuris sp.

Vacuna contra la fiebre hemorrágica argentina Candid#1 producida en la Argentina: Inmunogenicidad y seguridad

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Delia A. Enria

2010-06-01

Full Text Available Se realizó un estudio clínico en 946 voluntarios humanos sanos, donde se comparó la vacuna Candid#1 producida en Argentina con la elaborada en EE.UU., que había sido utilizada en estudios previos. Como objetivo primario se evaluó la equivalencia en la eficacia utilizando como marcador subrogante a la inmunogenicidad medida por detección de anticuerpos neutralizantes. Como objetivo secundario se evaluó la equivalencia en inocuidad comparando las tasas de reacciones adversas. Ambas vacunas mostraron una tasa equivalente de inmunogenicidad ligeramente superior al 95.5%, que es la eficacia estimada para Candid #1 en estudios previos. No se observaron eventos adversos graves relacionados con la vacuna. Los eventos adversos generales considerados relacionados fueron de escasa significación clínica y de resolución espontánea o con tratamiento sintomático; se presentaron en los receptores de ambas vacunas en tasas equivalentes (29.9% para la vacuna fabricada en la Argentina y 35.0% para la fabricada en EE.UU., e incluyeron: cefalea, decaimiento, mialgias, plaquetopenia leve (< 150 000 plaquetas/mm³, náuseas y/o vómitos, leucopenia leve (< 4 000 blancos/mm³, fiebre, dolor retroocular, mareos, microhematuria, lumbalgia y exantema. Estos resultados indican que la vacuna Candid #1 elaborada en la Argentina es equivalente a la elaborada en los EE.UU. Este estudio permitió el registro del biológico producido en la Argentina ante la autoridad regulatoria del país (ANMAT.

A Argentina depois da conversibilidade: um caso de novo-desenvolvimentismo?

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André Moreira Cunha

2009-03-01

Full Text Available This paper analyses the economic recovery in post-Convertibility Argentina. We try to identify if there are evidences to support the suggestion that Argentina could be an example of the so-called "new developmentalism".

A Combined Observational and Modeling Approach to Study Modern Dust Transport from the Patagonia Desert to East Antarctica

Science.gov (United States)

Gasso, S.; Stein, A.; Marino, F.; Castellano, E.; Udisti, R.; Ceratto, J.

2010-01-01

The understanding of present atmospheric transport processes from Southern Hemisphere (SH) landmasses to Antarctica can improve the interpretation of stratigraphic data in Antarctic ice cores. In addition, long range transport can deliver key nutrients normally not available to marine ecosystems in the Southern Ocean and may trigger or enhance primary productivity. However, there is a dearth of observational based studies of dust transport in the SH. This work aims to improve current understanding of dust transport in the SH by showing a characterization of two dust events originating in the Patagonia desert (south end of South America). The approach is based on a combined and complementary use of satellite retrievals (detectors MISR, MODIS, GLAS ,POLDER, OMI,), transport model simulation (HYSPLIT) and surface observations near the sources and aerosol measurements in Antarctica (Neumayer and Concordia sites). Satellite imagery and visibility observations confirm dust emission in a stretch of dry lakes along the coast of the Tierra del Fuego (TdF) island (approx.54deg S) and from the shores of the Colihue Huapi lake in Central Patagonia (approx.46deg S) in February 2005. Model simulations initialized by these observations reproduce the timing of an observed increase in dust concentration at the Concordia Station and some of the observed increases in atmospheric aerosol absorption (here used as a dust proxy) in the Neumayer station. The TdF sources were the largest contributors of dust at both sites. The transit times from TdF to the Neumayer and Concordia sites are 6-7 and 9-10 days respectively. Lidar observations and model outputs coincide in placing most of the dust cloud in the boundary layer and suggest significant de- position over the ocean immediately downwind. Boundary layer dust was detected as far as 1800 km from the source and approx.800 km north of the South Georgia Island over the central sub-Antarctic Atlantic Ocean. Although the analysis suggests the

Overview and perspectives for Open Access development in Argentina

Directory of Open Access Journals (Sweden)

Sandra Miguel

2013-04-01

Full Text Available This paper provides an overview and perspectives for development of the Open Access movement in Argentina, within the global and regional (Latin American context. It outlines the evolution and current state of initiatives around the two main approaches to Open Access, the golden and green roads. The main Open Access policies and support of OA movement by governments in Latin American region, and particularly in Argentina, are highlighted, while recent studies on publishing practices and authors’ positions regarding Open Access are presented. The paper concludes that the prospects for development of OA in Argentina, both through golden and green roads are favorable, with their strengths and shortcomings

Radiation vulcanization in Argentina

International Nuclear Information System (INIS)

Ferenaz, Guillermo W.; Smolko, Eduardo E.

1999-01-01

The possibilities of using in Argentina the radiation process to vulcanize natural latex are analyzed. Experimental studies to define the irradiation conditions have been carried out and the preliminary elaboration of an irradiation device that includes the chemical reactor has been started. (author)

78 FR 46610 - Lemon Juice From Argentina and Mexico

Science.gov (United States)

2013-08-01

... Argentina and Mexico Determination On the basis of the record \\1\\ developed in the subject five-year reviews... determines that termination of the suspended antidumping duty investigation on lemon juice from Mexico would...), entitled Lemon Juice from Argentina and Mexico: Investigation Nos. 731-TA-1105-1106 (Review). By order of...

78 FR 47006 - Lemon Juice From Argentina and Mexico

Science.gov (United States)

2013-08-02

... Argentina and Mexico Determination On the basis of the record \\1\\ developed in the subject five-year reviews... determines that termination of the suspended antidumping duty investigation on lemon juice from Mexico would...), entitled Lemon Juice from Argentina and Mexico: Investigation Nos. 731-TA-1105-1106 (Review). By order of...

FORMACIÓN Y EDUCACIÓN AMBIENTAL. UNA EXPERIENCIA INTEGRADORA DE APRENDIZAJE BASADO EN LOS PROBLEMAS DEL TERRITORIO

OpenAIRE

Ana María Raimond; José Gutiérrez Pérez; F. Javier Perales Palacios

2012-01-01

La formación de recursos humanos en carreras universitarias de corte ambiental es relativamente reciente en la Argentina. Puede decirse que las ofertas se inician promediando la década de los 90, de manera incipiente, fortaleciéndose luego a partir del inicio del siglo XXI. El caso que nos ocupa corresponde a una de esas ofertas de grado denominada Licenciatura en Gestión Ambiental, que pertenece a la Facultad de Humanidades y Ciencias Sociales de la Universidad Nacional de la Patagonia San J...

Update on women in physics in Argentina

OpenAIRE

Brudny, Vera Leonor; Lagorio, Cecilia; Frechero, Marisa Alejandra; Tamarit, Francisco

2016-01-01

Data collected 10 years ago in Argentina concluded that women in physics were underrepresented in many instances and that a “crystal ceiling” was firmly in place. We have collected updated data for several indicators and compared them with those obtained 10 years ago. Although there is not a clear conclusion to be drawn from this comparison, we try to explain the results within the framework of the changes in scientific policies in Argentina. Fil: Brudny, Vera Leonor. Universidad de Buenos...

Education and Dictatorship in Argentina 1976-1983

OpenAIRE

Kaufmann, Carolina

2000-01-01

Este artículo señala aspectos generales del autodenominado “Proceso” acaecido en Argentina (1976-1983). Se ofrecen evidencias de censura e imposición autoritaria en el sistema educativo. Asimismo, se explicitan elementos constitutivos de la educación personalizada perennialista y de la pedagogía de los valores que fue adoptada durante aquellos años. This article indicates general aspects of the self-styled "Process" occurred in Argentina (1976-1983). Evidence of censorship and authoritar...