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Sample records for south america western

  1. Cretaceous paleogeography and depositional cycles of western South America

    Science.gov (United States)

    Macellari, C. E.

    The western margin of South America was encroached upon by a series of marine advances that increased in extent from the Early Cretaceous to a maximum in the early Late Cretaceous for northern South America (Venezuela to Peru). In southern South America, however, the area covered by the marine advances decreased from a maximum in the Early Cretaceous to a minimum during mid-Cretaceous time, followed by a widespread advance at the end of the period. A series of unconformity-bounded depositional cycles was recognized in these sequences: five cycles in northern South America, and six (but not exactly equivalent) cycles in the Cretaceous back-arc basins of southern South America (Neuquén and Austral, or Magallanes, Basins). Both widespread anoxic facies and maximum flooding of the continent in northern South America coincide in general terms with recognized global trends, but this is not the case in southern South America. Here, anoxic facies are restricted to the Lower Cretaceous and seem to be controlled by local aspects of the basin evolution and configuration. The contrasts observed between northern and southern South America can be explained by differences in tectonic setting and evolution. To the north, sediments were deposited around the tectonically stable Guayana-Brazilian Massifs, and thus registered global "signals" such as anoxic events and major eustatic changes. The southern portion of the continent, on the contrary, developed in an active tectonic setting. Here, the mid-Cretaceous Peruvian Orogeny overprinted, to a large extent, world-wide trends and only the earliest and latest Cretaceous conform to global depositional patterns.

  2. Palm harvest impacts in north-western South America

    DEFF Research Database (Denmark)

    Balslev, Henrik

    2011-01-01

    Tropical forests harbor thousands of useful plants that are harvested and used in subsistence economies or traded in local, regional or international markets. The effect on the ecosystem is little known, and the forests resilience is badly understood. Palms are the most useful group of plants...... in tropical American forests. This paper introduces a cross-disciplinary study of the effects of harvesting palm products from the tropical forests in north-western South America. The size of the resource is estimated through palm community studies in the different forest formations that determines the number...... of species and individuals of all palm species. The genetic structure of useful palm species is studied to determine how much harvesting of the species contributes to genetic erosion of its populations, and whether extraction can be made without harm. Almost all palm species are used in rural communities...

  3. North-South precipitation patterns in western North America on interannual-to-decadal timescales

    Science.gov (United States)

    Dettinger, M.D.; Cayan, D.R.; Diaz, Henry F.; Meko, D.M.

    1998-01-01

    The overall amount of precipitation deposited along the West Coast and western cordillera of North America from 25??to 55??N varies from year to year, and superimposed on this domain-average variability are varying north-south contrasts on timescales from at least interannual to interdecadal. In order to better understand the north-south precipitation contrasts, their interannual and decadal variations are studied in terms of how much they affect overall precipitation amounts and how they are related to large-scale climatic patterns. Spatial empirical orthogonal functions (EOFs) and spatial moments (domain average, central latitude, and latitudinal spread) of zonally averaged precipitation anomalies along the westernmost parts of North America are analyzed, and each is correlated with global sea level pressure (SLP) and sea surface temperature series, on interannual (defined here as 3-7 yr) and decadal (>7 yr) timescales. The interannual band considered here corresponds to timescales that are particularly strong in tropical climate variations and thus is expected to contain much precipitation variability that is related to El Nino-Southern Oscillation; the decadal scale is defined so as to capture the whole range of long-term climatic variations affecting western North America. Zonal EOFs of the interannual and decadal filtered versions of the zonal-precipitation series are remarkably similar. At both timescales, two leading EOFs describe 1) a north-south seesaw of precipitation pivoting near 40??N and 2) variations in precipitation near 40??N, respectively. The amount of overall precipitation variability is only about 10% of the mean and is largely determined by precipitation variations around 40??-45??N and most consistently influenced by nearby circulation patterns; in this sense, domain-average precipitation is closely related to the second EOF. The central latitude and latitudinal spread of precipitation distributions are strongly influenced by precipitation

  4. Gastroptychus Cavimurus sp. nov., a new Chirostylid (Crustacea, Decapoda, Anomura) from off the western coast of South America

    NARCIS (Netherlands)

    Baba, K.

    1977-01-01

    During the second cruise of the Japanese Research Vessel "Kaiyo Maru" to the western coast of South America in 1968-69, Dr. Osame Tabeta of the Shimonoseki University of Fisheries, then on the staff of the Kyushu University, collected a number of galatheids off the northern Peruvian coast. All of

  5. Correlation of proterozoic sediments of Western and Central Africa and South America based upon radiochronological and paleontological data

    International Nuclear Information System (INIS)

    Bonhomme, M.G.

    1982-01-01

    Nearly 70 new Rb-Sr isochron ages and many K-Ar conventional ages have been determined between 1975 and 1980 on Proterozoic sedimentary or metasedimentary sequences in western and Central Africa and South America. Some stratigraphic results have been established: (1) five formations have been dated of the Lower Proterozoic; (2) a long sedimentation gap occurs, mainly in western Africa and in some regions of Central Africa and South America between nearly 1600 and 1100 Ma; (3) the upper Riphean assemblages of stromatolites have been dated and compared to those of the Eurasian craton; (4) two main glacial events have been dated, the first one placed at ca. 950 Ma, the second during the Vendian, at ca. 650-620 Ma; (5) it can be stated that, when applied to Precambrian sequences, all stratigraphic methods must be used together. (Auth.)

  6. Geographic disparities of asthma prevalence in south-western United States of America

    Directory of Open Access Journals (Sweden)

    Lung-Chang Chien

    2014-11-01

    Full Text Available Asthma is one of the most prevalent chronic diseases in the United States of America (USA, and many of its risk factors have so far been investigated and identified; however, evidence is limited on how spatial disparities impact the disease. The purpose of this study was to provide scientific evidence on the location influence on asthma in the four states of south- western USA (California, Arizona, New Mexico and Texas which, together, include 360 counties. The Behavioral Risk Factor Surveillance System database for these four states covering the period of 2000 to 2011 was used in this analysis, and a Bayesian structured additive regression model was applied to analyse by a geographical information system. After adjusting for individual characteristics, socioeconomic status and health behaviour, this study found higher odds associated with asth- ma and a likely cluster around the Bay Area in California, while lower odds appeared in several counties around the larger cities of Texas, such as Dallas, Houston and San Antonio. The significance map shows 43 of 360 counties (11.9% to be high-risk areas for asthma. The level of geographical disparities demonstrates that the county risk of asthma prevalence varies significantly and can be about 19.9% (95% confidence interval: 15.3-25.8 higher or lower than the overall asthma prevalence. We provide an efficient method to utilise and interpret the existing surveillance data on asthma. Visualisation by maps may help deliver future interventions on targeted areas and vulnerable populations to reduce geographical disparities in the burden of asthma.

  7. Freshwater fish faunas, habitats and conservation challenges in the Caribbean river basins of north-western South America.

    Science.gov (United States)

    Jiménez-Segura, L F; Galvis-Vergara, G; Cala-Cala, P; García-Alzate, C A; López-Casas, S; Ríos-Pulgarín, M I; Arango, G A; Mancera-Rodríguez, N J; Gutiérrez-Bonilla, F; Álvarez-León, R

    2016-07-01

    The remarkable fish diversity in the Caribbean rivers of north-western South America evolved under the influences of the dramatic environmental changes of neogene northern South America, including the Quechua Orogeny and Pleistocene climate oscillations. Although this region is not the richest in South America, endemism is very high. Fish assemblage structure is unique to each of the four aquatic systems identified (rivers, streams, floodplain lakes and reservoirs) and community dynamics are highly synchronized with the mono-modal or bi-modal flooding pulse of the rainy seasons. The highly seasonal multispecies fishery is based on migratory species. Freshwater fish conservation is a challenge for Colombian environmental institutions because the Caribbean trans-Andean basins are the focus of the economic development of Colombian society, so management measures must be directed to protect aquatic habitat and their connectivity. These two management strategies are the only way for helping fish species conservation and sustainable fisheries. © 2016 The Fisheries Society of the British Isles.

  8. Arboviral Etiologies of Acute Febrile Illnesses in Western South America, 2000–2007

    Science.gov (United States)

    Forshey, Brett M.; Guevara, Carolina; Laguna-Torres, V. Alberto; Cespedes, Manuel; Vargas, Jorge; Gianella, Alberto; Vallejo, Efrain; Madrid, César; Aguayo, Nicolas; Gotuzzo, Eduardo; Suarez, Victor; Morales, Ana Maria; Beingolea, Luis; Reyes, Nora; Perez, Juan; Negrete, Monica; Rocha, Claudio; Morrison, Amy C.; Russell, Kevin L.; J. Blair, Patrick; Olson, James G.; Kochel, Tadeusz J.

    2010-01-01

    Background Arthropod-borne viruses (arboviruses) are among the most common agents of human febrile illness worldwide and the most important emerging pathogens, causing multiple notable epidemics of human disease over recent decades. Despite the public health relevance, little is know about the geographic distribution, relative impact, and risk factors for arbovirus infection in many regions of the world. Our objectives were to describe the arboviruses associated with acute undifferentiated febrile illness in participating clinics in four countries in South America and to provide detailed epidemiological analysis of arbovirus infection in Iquitos, Peru, where more extensive monitoring was conducted. Methodology/Findings A clinic-based syndromic surveillance system was implemented in 13 locations in Ecuador, Peru, Bolivia, and Paraguay. Serum samples and demographic information were collected from febrile participants reporting to local health clinics or hospitals. Acute-phase sera were tested for viral infection by immunofluorescence assay or RT-PCR, while acute- and convalescent-phase sera were tested for pathogen-specific IgM by ELISA. Between May 2000 and December 2007, 20,880 participants were included in the study, with evidence for recent arbovirus infection detected for 6,793 (32.5%). Dengue viruses (Flavivirus) were the most common arbovirus infections, totaling 26.0% of febrile episodes, with DENV-3 as the most common serotype. Alphavirus (Venezuelan equine encephalitis virus [VEEV] and Mayaro virus [MAYV]) and Orthobunyavirus (Oropouche virus [OROV], Group C viruses, and Guaroa virus) infections were both observed in approximately 3% of febrile episodes. In Iquitos, risk factors for VEEV and MAYV infection included being male and reporting to a rural (vs urban) clinic. In contrast, OROV infection was similar between sexes and type of clinic. Conclusions/Significance Our data provide a better understanding of the geographic range of arboviruses in South

  9. Anaglyph, South America

    Science.gov (United States)

    2003-01-01

    This anaglyph (stereoscopic view) of South America was generated with data from the Shuttle Radar Topography Mission (SRTM). It is best viewed at or near full resolution with anaglyph glasses. For this broad view the resolution of the data was first reduced to 30 arcseconds (about 928 meters north-south but variable east-west), matching the best previously existing global digital topographic data set called GTOPO30. The data were then resampled to a Mercator projection with approximately square pixels (about one kilometer, or 0.6 miles, on each side). Even at this decreased resolution the variety of landforms comprising the South American continent is readily apparent.Topographic relief in South America is dominated by the Andes Mountains, which extend all along the Pacific Coast. These mountains are created primarily by the convergence of the Nazca and South American tectonic plates. The Nazca Plate, which underlies the eastern Pacific Ocean, slides under western South America resulting in crustal thickening, uplift, and volcanism. Another zone of plate convergence occurs along the northwestern coast of South America where the Caribbean Plate also slides under the South American Plate and forms the northeastern extension of the Andes Mountains.East of the Andes, much of northern South America drains into the Amazon River, the world's largest river in terms of both watershed area and flow volume. Topographic relief is very low in much of the Amazon Basin but SRTM data provide an excellent detailed look at the basin's three-dimensional drainage pattern, including the geologic structural trough (syncline) that hosts the eastern river channel.North of the Amazon, the Guiana Highlands commonly stand in sharp contrast to the surrounding lowlands, indeed hosting the world's tallest waterfall, Angel Falls (979 meters or 3212 feet). Folded and fractured bedrock structures are distinctive in the topographic pattern.South of the Amazon, the Brazilian Highlands show a mix of

  10. Mesozoic–Cenozoic Evolution of the Western Margin of South America: Case Study of the Peruvian Andes

    Directory of Open Access Journals (Sweden)

    Laura Gonzalez

    2013-06-01

    Full Text Available Based on the structural style and physiographic criteria, the Central Andes of Peru can be divided into segments running parallel to the Pacific coast. The westernmost segment, the Coastal Belt, consists of a Late Jurassic–Cretaceous volcanic arc sequence that was accreted to the South American craton in Cretaceous times. The Mesozoic strata of the adjacent Western Cordillera represent an ENE-vergent fold-and-thrust belt that formed in Eocene times. Tight upright folds developed above a shallow detachment horizon in the West, while more open folds formed above a deeper detachment horizon towards the East and in the neighboring Central Highlands. A completely different style with steeply dipping reverse faults and open folds affecting the Neoproterozoic crystalline basement is typical for the Eastern Cordillera. The Subandean Zone is characterized by mainly NE-vergent imbricate thrusting which occurred in Neogene times. A quantitative estimate of the shortening of the orogen obtained from balanced cross-sections indicates a total shortening of 120–150 km (24%–27%. This shortening was coevel with the Neogene westward drift of South America, occurred at rates between 3 and 4.7 mm/year and was responsible for the high elevation of the Peruvian Andes.

  11. Structural signatures of water-soluble organic aerosols in contrasting environments in South America and Western Europe.

    Science.gov (United States)

    Duarte, Regina M B O; Matos, João T V; Paula, Andreia S; Lopes, Sónia P; Pereira, Guilherme; Vasconcellos, Pérola; Gioda, Adriana; Carreira, Renato; Silva, Artur M S; Duarte, Armando C; Smichowski, Patricia; Rojas, Nestor; Sanchez-Ccoyllo, Odon

    2017-08-01

    This study describes and compares the key structural units present in water-soluble organic carbon (WSOC) fraction of atmospheric aerosols collected in different South American (Colombia - Medellín and Bogotá, Peru - Lima, Argentina - Buenos Aires, and Brazil - Rio de Janeiro, São Paulo, and Porto Velho, during moderate (MBB) and intense (IBB) biomass burning) and Western European (Portugal - Aveiro and Lisbon) locations. Proton nuclear magnetic resonance ( 1 H NMR) spectroscopy was employed to assess the relative distribution of non-exchangeable proton functional groups in aerosol WSOC of diverse origin, for the first time to the authors' knowledge in South America. The relative contribution of the proton functional groups was in the order H-C > H-C-C= > H-C-O > Ar-H, except in Porto Velho during MBB, Medellín, Bogotá, and Buenos Aires, for which the relative contribution of H-C-O was higher than that of H-C-C=. The 1 H NMR source attribution confirmed differences in aging processes or regional sources between the two geographic regions, allowing the differentiation between urban combustion-related aerosol and biological particles. The aerosol WSOC in Aveiro, Lisbon, and Rio de Janeiro during summer are more oxidized than those from the remaining locations, indicating the predominance of secondary organic aerosols. Fresh emissions, namely of smoke particles, becomes important during winter in Aveiro and São Paulo, and in Porto Velho during IBB. The biosphere is an important source altering the chemical composition of aerosol WSOC in South America locations. The source attribution in Medellín, Bogotá, Buenos Aires, and Lima confirmed the mixed contributions of biological material, secondary formation, as well as urban and biomass burning emissions. Overall, the information and knowledge acquired in this study provide important diagnostic tools for future studies aiming at understanding the water-soluble organic aerosol problem, their sources and

  12. Neosporosis in South America.

    Science.gov (United States)

    Moore, D P

    2005-01-20

    This work gathers reports about Neospora-infections in South America. Neospora-infections have been reported from Argentina, Brazil, Chile, Paraguay, Peru and Uruguay. Evidence of exposure to N. caninum was mentioned in cattle, goats, sheep, dogs, cats, water buffaloes, alpacas, llamas, South American opossums, wolves and other wild canids. No antibodies were found in horses. Interesting epidemiological and pathological data were described. Two isolations were performed from dogs, one from cattle, and recently five from water buffaloes. Since the cattle industry is important in South America and reproductive losses caused by Neospora-infection have been identified, more investigations are needed in order to understand its epidemiology and control the disease.

  13. Influence of the stratospheric humidity and methane on the ozone column depletion over the western side of South America

    International Nuclear Information System (INIS)

    Da Silva, L.; Morales, L.; Cordero, R.R.

    2009-01-01

    The ozone column depletion over the western side of South America has been previously explained as a consequence of winds in the area of the depletion, which lead to the compression and thinning of the ozone layer. However, humidity and methane (originated in the Amazon forest and the Pacific Ocean) transported by these winds toward the stratosphere may also have a role in the ozone depletion. Oxidation of methane generates additional humidity, which in turn reacts with ozone, destroying it. Humidity and methane levels were measured by NASA and HALOE during an ozone depletion event (January 1998) that occurred along with El Nino. By analyzing these measurements, we found that, at different altitudes, changes in the humidity seem to be associated with changes in the ozone such that an increment of humidity may lead to an ozone depletion. Moreover, we found that during the event, the sum 2CH4+H2O was roughly constant only at altitudes lower than 50 km; the ratio CH4/H2O exhibited an exponential decay with the altitude that may allow assessing the generation mechanism of stratospheric humidity from methane.

  14. Geographic disparities of asthma prevalence in south-western United States of America.

    Science.gov (United States)

    Chien, Lung-Chang; Alamgir, Hasanat

    2014-11-01

    Asthma is one of the most prevalent chronic diseases in the United States of America (USA), and many of its risk factors have so far been investigated and identified; however, evidence is limited on how spatial disparities impact the disease. The purpose of this study was to provide scientific evidence on the location influence on asthma in the four states of southwestern USA (California, Arizona, New Mexico and Texas) which, together, include 360 counties. The Behavioral Risk Factor Surveillance System database for these four states covering the period of 2000 to 2011 was used in this analysis, and a Bayesian structured additive regression model was applied to analyse by a geographical information system. After adjusting for individual characteristics, socioeconomic status and health behaviour, this study found higher odds associated with asthma and a likely cluster around the Bay Area in California, while lower odds appeared in several counties around the larger cities of Texas, such as Dallas, Houston and San Antonio. The significance map shows 43 of 360 counties (11.9%) to be high-risk areas for asthma. The level of geographical disparities demonstrates that the county risk of asthma prevalence varies significantly and can be about 19.9% (95% confidence interval: 15.3-25.8) higher or lower than the overall asthma prevalence. We provide an efficient method to utilise and interpret the existing surveillance data on asthma. Visualisation by maps may help deliver future interventions on targeted areas and vulnerable populations to reduce geographical disparities in the burden of asthma.

  15. Characters and phylogenetic relationships of nectar-feeding bats, with descriptions of new Lonchophylla from western South America (Mammalia: Chiroptera: Phyllostomidae: Lonchophyllini)

    Science.gov (United States)

    Woodman, N.; Timm, R.M.

    2006-01-01

    The Neotropical Lonchophyllini (Chiropter: Phyllostomidae) currently comprise four genera and thirteen species of nectar-feeding bats. These species often are separated into larger-bodied (eight species) and smaller-bodied (five species) forms to aid in identification. Our morphological and morphometrical analyses of the smaller Lonchophyllini revealed the existence of two distinctive, previously undescribed species of bats of the genus Lonchophylla from western South America. We describe a new form from Amazonian Peru as Lonchophylla pattoni and one from western Colombia as Lonchophylla cadenai. Phyllogenetic analysis of the Lonchophyllini based primarily on morphological characters indicates that these two new species are closely related to Lonchophylla thomasi.

  16. Literacy in South America.

    Science.gov (United States)

    Hornberger, Nancy H.

    1991-01-01

    Literacy in South America must be understood in terms of the linguistic diversity there, where only 2 of 14 nations and territories are monolingual. Oral traditions, standardization of indigenous languages, nonstandard varieties of colonial languages, bilingual education and mother tongue literacy, literacy teaching, and politics are discussed.…

  17. Monograph of the Genus Elodea (Hydrocharitaceae: Part 2. The species found in the Andes and Western South America Monograph of the Genus Elodea (Hydrocharitaceae: Part 2. The species found in the Andes and Western South America

    Directory of Open Access Journals (Sweden)

    St. John Harold

    1964-12-01

    Full Text Available The genus Elodea Richard in Michaux was first published in 1803 (Fl. Bor.-Am. 1: 20, 1803, based upon the single species. E. Canadensis from Montreal, Quebec, Canada. Though this was stated to have perfect flowers, it is now certain that the holotype specimens and the plants in nature are dioecious. Very abundant are plants bearing pistillate flowers with three stigmas and three acicular staminodia. Staminate plants are rare, but occur throughout the natural range of the species. Their flowers have nine stamens, but no trace of a gynoecium. Two well known species are now separated and placed in the genus Egeria Planch., a group just monographed by the writer. Left in Elodea are seventeen species. These are to be found in two broad areas, the northern ones in the United States and southern Canada; the southern ones in South America. As yet there is no evidence of any indigenous species of Elodea in Central America.The genus Elodea Richard in Michaux was first published in 1803(Fl. Bor.-Am. 1: 20, 1803, based upon the single species. E. Canadensis from Montreal, Quebec, Canada. Though this was stated to have perfect flowers, it is now certain that the holotype specimens and the plants in nature are dioecious. Very abundant are plants bearing pistillate flowers with three stigmas and three acicular staminodia. Staminate plants are rare, but occur throughout the natural range of the species. Their flowers have nine stamens, but no trace of a gynoecium. Two well known species are now separated and placed in the genus Egeria Planch., a group just monographed by the writer. Left in Elodeaare seventeen species. These are to be found in two broad areas, the northern ones in the United Statesand southern Canada; the southern ones in South America. As yet there is no evidence of any indigenous species of Elodea in Central America.

  18. The Africa South America Intercontinental Teleconnection.

    Science.gov (United States)

    Cook, K. H.; Hsieh, J.-S.; Hagos, S. M.

    2004-07-01

    The influence of heating over Africa on the South American precipitation climatology, and the influence of South America on Africa, is examined through the application of GCM simulations with idealized boundary conditions and perpetual solstice (January and July) conditions.The presence of Africa is associated with a pronounced (up to 4 mm day-1) decrease in precipitation in Brazil's Nordeste region during austral summer. Low-level moisture divergence and dry-air advection associated with the downbranch of a Walker circulation induced by heating over southern Africa is amplified over the Nordeste due to the response of the land surface. The response is much smaller during austral winter due to differences in the heat source over Africa and a reduced sensitivity in the surface heat balance over tropical South America. Forcing from South America in January shifts the position of the South Indian convergence zone (SICZ) to the southwest over southern Africa in association with the formation of the South Atlantic convergence zone (SACZ). In July, a Rossby wave train generated over South America induces a response in the surface temperature of Africa that leads to stronger precipitation in central and western Africa.This study suggests a zonal mode of variability for South American and African circulation and precipitation fields. The resulting perturbations depend as much on land surface atmosphere interactions as on the direct forcing from the adjacent continent, and the mechanisms are highly nonlinear.

  19. Biogeographic links between southern Atlantic Forest and western South America: Rediscovery, re-description, and phylogenetic relationships of two rare montane anole lizards from Brazil.

    Science.gov (United States)

    Prates, Ivan; Melo-Sampaio, Paulo Roberto; Drummond, Leandro de Oliveira; Teixeira, Mauro; Rodrigues, Miguel Trefaut; Carnaval, Ana Carolina

    2017-08-01

    Data on species ranges and phylogenetic relationships are key in historical biogeographical inference. In South America, our understanding of the evolutionary processes that underlie biodiversity patterns varies greatly across regions. Little is known, for instance, about the drivers of high endemism in the southern montane region of the Atlantic Rainforest. In this region, former biogeographic connections with other South American ecosystems have been invoked to explain the phylogenetic affinities of a number of endemic taxa. This may also be the case of the montane anole lizards Anolis nasofrontalis and A. pseudotigrinus, known from few specimens collected more than 40years ago. We combine new genetic data with published sequences of species in the Dactyloa clade of Anolis to investigate the phylogenetic relationships of A. nasofrontalis and A. pseudotigrinus, as well as estimate divergence times from their closest relatives. Based on newly sampled and previously overlooked specimens, we provide a taxonomic re-description of those two taxa. Our phylogenetic analysis recovered six main clades within Dactyloa, five of which were previously referred to as species series (aequatorialis, heterodermus, latifrons, punctatus, roquet). A sixth clade clustered A. nasofrontalis and A. pseudotigrinus with A. dissimilis from western Amazonia, A. calimae from the Andes, A. neblininus from the Guiana Shield, and two undescribed Andean taxa. We therefore define a sixth species series within Dactyloa: the neblininus series. Close phylogenetic relationships between highly disjunct, narrowly-distributed anoles suggest that patches of suitable habitat connected the southern Atlantic Forest to western South America during the Miocene, in agreement with the age of former connections between the central Andes and the Brazilian Shield as a result of Andean orogeny. The data also support the view of recurrent evolution (or loss) of a twig anole-like phenotype in mainland anoles, in

  20. Rediscovering South America

    National Research Council Canada - National Science Library

    Ray, Charles; Shearer, Thomas D; Staszak, Michael

    1997-01-01

    In presenting the U.S. National Security Strategy of Engagement and Enlargement the Clinton Administration states that, "The unprecedented triumph of democracy and market economies throughout the (Latin America...

  1. Breaking away to South America

    CERN Multimedia

    Anaïs Schaeffer

    2011-01-01

    In December 2010, Peter Dreesen of CERN’s Technology Department (TE) returned from a long trip to South America. In four months he traversed the entire Andean range, from the equator to a latitude of 55 degrees south—on a bicycle!   Peter Dreesen on the Salar de Uyuni Lake, Bolivia. 11 000 kilometres is one long bike ride! And yet, that’s what Peter Dreesen did, travelling from Quito, Ecuador to Ushuaia, Argentina. Peter, an engineer in the TE Department, is no novice: the year before, he cycled from Paris to Peking, a distance of 13 500 kilometres, in just over four months. His latest voyage began last August, when he loaded his bicycle and boarded a plane for South America. In the saddle. After a week of acclimatisation at three thousand metres altitude, Peter left Quito on 6 August 2010. He arrived in Ushuaia (el fin del mundo, the end of the world, as it’s known in South America) on 12 December 2010. He recounts: “It was a bizarre sensation...

  2. Impact craters in South America

    CERN Document Server

    Acevedo, Rogelio Daniel; Ponce, Juan Federico; Stinco, Sergio G

    2015-01-01

    A complete and updated catalogue of impact craters and structures in South America from 2014 is presented here. Approximately eighty proven, suspected and disproven structures have been identified by several sources in this continent. All the impact sites of this large continent have been exhaustively reviewed: the proved ones, the possible ones and some very doubtful. Many sites remain without a clear geological ""in situ"" confirmation and some of them could be even rejected. Argentina and Brazil are leading the list containing almost everything detected. In Bolivia, Chile, Colombia, Guyana,

  3. South America, Shaded Relief and Colored Height

    Science.gov (United States)

    2003-01-01

    This image of South America was generated with data from the Shuttle Radar Topography Mission (SRTM). For this broad view the resolution of the data was first reduced to 30 arcseconds (about 928 meters north-south but variable east-west), matching the best previously existing global digital topographic data set called GTOPO30. The data were then resampled to a Mercator projection with approximately square pixels (about one kilometer, or 0.6 miles, on each side). Even at this decreased resolution the variety of landforms comprising the South American continent is readily apparent.Topographic relief in South America is dominated by the Andes Mountains, which extend all along the Pacific Coast. These mountains are created primarily by the convergence of the Nazca and South American tectonic plates. The Nazca Plate, which underlies the eastern Pacific Ocean, slides under western South America resulting in crustal thickening, uplift, and volcanism. Another zone of plate convergence occurs along the northwestern coast of South America where the Caribbean Plate also slides under the South American Plate and forms the northeastern extension of the Andes Mountains.East of the Andes, much of northern South America drains into the Amazon River, the world's largest river in terms of both watershed area and flow volume. Topographic relief is very low in much of the Amazon Basin but SRTM data provide an excellent detailed look at the basin's three-dimensional drainage pattern, including the geologic structural trough (syncline) that hosts the eastern river channel.North of the Amazon, the Guiana Highlands commonly stand in sharp contrast to the surrounding lowlands, indeed hosting the world's tallest waterfall, Angel Falls (979 meters or 3212 feet). Folded and fractured bedrock structures are distinctive in the topographic pattern.South of the Amazon, the Brazilian Highlands show a mix of landforms, including some broad areas of consistent topographic patterns that indicate the

  4. Gravity derived Moho for South America

    NARCIS (Netherlands)

    van der Meijde, M.; Julia, J.; Assumpcao, M.

    2013-01-01

    Crustal structure in South America is one of the least understood among the Earth's continental areas. Variations in crustal thickness are still poorly constrained over large portions of the continent because of scarce or unevenly distributed crustal thickness estimates throughout South America. To

  5. SOUTH AMERICA: INDUSTRIAL ROUNDWOOD SUPPLY POTENTIAL

    Directory of Open Access Journals (Sweden)

    Ronalds W. Gonzalez

    2008-02-01

    Full Text Available South America has substantial potential to expand its forest plantations and raw material supply. From 1997 to 2005, South America had a high annual growth rate in the production of industrial roundwood, with Brazil and Chile being the most important countries. In the same period, Asia had the only negative regional production growth rate in the world, and China became the largest round wood importer in the world. This paper summarizes the status of production, consumption, imports, and exports of industrial roundwood and forest products in South America. Produc-tion and exports from South America have continually increased at annual growth rates exceeding the forestry sector in general and the U.S. in particular. Based on timber growing investments to date, a strong timber production and forest products manufacturing sector has developed in the Southern Cone countries of Chile, Brazil, Argentina, and Uruguay, and is increasing in other countries in Latin America. There will be continued opportunities for forest plantations and new manufacturing facilities throughout South America, tempered somewhat by perceived country financial and political risks. These opportunities will allow South America to increase its share of world production and increase imports to North America and to Asia.

  6. Browning boreal forests of western North America

    Science.gov (United States)

    Verbyla, David

    2011-12-01

    , suggesting that direct temperature stress might be a factor in some species. Since warm growing seasons are also typically dry growing seasons, direct temperature stress and moisture stress could occur simultaneously. For example, 2004 was the warmest summer in over 200 years in boreal Alaska (Barber et al 2004) but it was also during a drought with less than 50 mm of summer precipitation recorded in Fairbanks. In Fairbanks, the length of the growing season, as defined as the period above freezing, has increased by 45 per cent over the past 100 years, with no significant increase in precipitation (Wendler and Shulski 2009). Regional winter runoff has increased, likely associated with permafrost thawing (Brabets and Walvoord 2009), while surface water has decreased, likely associated with increased evapotranspiration (Riordan et al 2006, Anderson et al 2007, Berg et al 2009). The mean annual air temperature in boreal Alaska has increased by over 1.5 °C during the past 50 years (Stafford et al 2000), and is projected to increase by 3-7 °C by end of this century (Walsh et al 2008). Thus, it would be surprising if a declining NDVI trend was not occurring in the western boreal region of North America as the climate continues to warm. Insects and disease in the North American boreal forest may also affect the NDVI browning trends (Malmström and Raffa 2000), as the life histories of damaging insects may be linked to a warming boreal climate. For example, warmer temperatures contributed to the spruce beetle outbreaks in Alaska with a reduction in the beetle life cycle from two years to one year (Berg et al 2006). Thus, as the boreal climate continues to warm, tree growth reduction and mortality from insects and diseases may become more substantial. In boreal Alaska, recent alder dieback and mortality is likely to be related to alder's susceptibility to a canker-causing fungus in drought years (Ruess et al 2009). Recent widespread and prolonged outbreaks of aspen leaf miner and a

  7. The thrust belts of Western North America

    Energy Technology Data Exchange (ETDEWEB)

    Moulton, F.C.

    1993-08-01

    Most of the Basin and Range physiographic province of western North America is now believed to be part of the overthrust. The more obvious overthrust belt along the eastern edge of the Basin and Range Province is named the Sevier orogenic belt, where older rocks are observed thrust onto younger rocks. More detailed surface geological mapping, plus deep multiple-fold geophysical work and many oil and gas wildcat wells, have confirmed an east-vergent shortened and stacked sequence is present in many places in the Basin and Range. This western compressive deformed area in east central Nevada is now named the Elko orogenic belt by the U.S. Geological Survey. This older compressed Elko orogenic belt started forming approximately 250 m.y. ago when the North American plate started to move west as the Pangaea supercontinent started to fragment. The North American plate moved west under the sediments of the Miogeocline that were also moving west. Surface-formed highlands and oceanic island arcs on the west edge of the North American plate restricted the westward movement of the sediments in the Miogeocline, causing east-vergent ramp thrusts to form above the westward-moving North American plate. The flat, eastward-up-cutting thrust assemblages moved on the detachment surfaces.

  8. Energy market integration in South America

    International Nuclear Information System (INIS)

    Hammons, T.J.; Franco, N. de; Sbertoli, L.V.; Khelil, C.; Rudnick, H.; Clerici, A.; Longhi, A.

    1997-01-01

    This article is a summary of presentations made during the 1997 Winter Meeting panel session on Power and Natural Gas in Latin America: Towards an Integrated Market. Reregulation and demand for energy resources to support economic growth are driving international natural gas and electricity exchange initiatives. Panelists focused on the gas and electric power industry in Latin America in terms of the: transport of gas or transmission of electricity; energy market integration in the southern cone of South America; and issues on gas use for electricity generation in South America countries. Countries such as Argentina, Bolivia, and Peru will export natural gas to Brazil, Uruguay, Paraguay and Chile, an the energy matrices of these countries will change

  9. SOUTH AMERICA: Looking for partners

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    A Regional Meeting on Fundamental Physics organized at the CIF International Physics Centre in Bogota, Colombia, in April, looked at future international collaboration possibilities for physicists from the South American Andean region in general, and from Colombia in particular

  10. Status of radiation curing in South America

    International Nuclear Information System (INIS)

    Machado, L.D.B.; Rotta, A.C.; Petrie, I.

    2007-01-01

    In August 2006, an agreement between the Rad tech International North America and the ATBCR, the Brazillian Technical Association for Radiation cure, turns ATCBR into RadTech South America. This new institution starts with already 10 years of history and pioneering technical experience and achievements in UV and EB radiation cure. Both RadTech institutions have asserted a whole cooperation and information exchange to continue with the initial ATBCR compromise in promoting UV and EB curing technology and to make it available to professionals, enterprise and other organizations. The RadTech South America has it's headquarter at the Energy and Nuclear Research Institute, IPEN, in Sao Paulo, Brazil, from whom also gets sponsorship. (Author)

  11. Fish biodiversity and conservation in South America.

    Science.gov (United States)

    Reis, R E; Albert, J S; Di Dario, F; Mincarone, M M; Petry, P; Rocha, L A

    2016-07-01

    The freshwater and marine fish faunas of South America are the most diverse on Earth, with current species richness estimates standing above 9100 species. In addition, over the last decade at least 100 species were described every year. There are currently about 5160 freshwater fish species, and the estimate for the freshwater fish fauna alone points to a final diversity between 8000 and 9000 species. South America also has c. 4000 species of marine fishes. The mega-diverse fish faunas of South America evolved over a period of >100 million years, with most lineages tracing origins to Gondwana and the adjacent Tethys Sea. This high diversity was in part maintained by escaping the mass extinctions and biotic turnovers associated with Cenozoic climate cooling, the formation of boreal and temperate zones at high latitudes and aridification in many places at equatorial latitudes. The fresh waters of the continent are divided into 13 basin complexes, large basins consolidated as a single unit plus historically connected adjacent coastal drainages, and smaller coastal basins grouped together on the basis of biogeographic criteria. Species diversity, endemism, noteworthy groups and state of knowledge of each basin complex are described. Marine habitats around South America, both coastal and oceanic, are also described in terms of fish diversity, endemism and state of knowledge. Because of extensive land use changes, hydroelectric damming, water divergence for irrigation, urbanization, sedimentation and overfishing 4-10% of all fish species in South America face some degree of extinction risk, mainly due to habitat loss and degradation. These figures suggest that the conservation status of South American freshwater fish faunas is better than in most other regions of the world, but the marine fishes are as threatened as elsewhere. Conserving the remarkable aquatic habitats and fishes of South America is a growing challenge in face of the rapid anthropogenic changes of the 21

  12. Population structures of Astragalus filipes collections from western North America

    Science.gov (United States)

    B. Shaun Bushman; Kishor Bhattarai; Douglas A. Johnson

    2010-01-01

    The majority of species used for revegetation in semi-arid western rangelands of North America are grasses, with few forbs and nearly no legumes. Astragalus filipes (Torr. Ex A. Gray) is a western North American legume and a promising candidate for use in rangeland revegetation, but assessments of plant species diversity and structure are necessary to determine which...

  13. Re-ordering the Region? China, Latin America and the Western Hemisphere

    Directory of Open Access Journals (Sweden)

    Nicola Philips

    2011-04-01

    Full Text Available – China in Latin America: The Whats and Wherefores, by R. Evan Ellis. Boulder, CO: Lynne Rienner, 2009.– Latin America Facing China: South-South Relations beyond the Washington Consensus, edited by Alex E. Fernández Jilberto and Barbara Hogenboom. New York & Oxford: Berghahn Books, 2010.– The Dragon in the Room: China and the Future of Latin American Industrialization, by Kevin P. Gallagher and Roberto Porzecanski. Stanford, CA: Stanford University Press, 2010.– China and Latin America: Economic Relations in the Twenty-First Century, edited by Rhys Jenkins and Enrique Dussel Peters. Bonn: Deutsches Institut für Entwicklungspolitik, 2009.– China’s Expansion into the Western Hemisphere: Implications for Latin America and the United States, edited by Riordan Roett and Guadalupe Paz. Washington, DC: The Brookings Institution, 2008.

  14. Potential for Conflict in South America

    Science.gov (United States)

    1988-06-01

    34Anglo-Argentine War." 2 Dov S. Zakheim, "The South Atlantic Conflict: Strategic, Military, and Technological Lessons", in Alberto Coll and Anthony Arendt...For example, Brazil’s period of greatest military growth after the war was during the civilian qovernment or Juscelino Kubitschek (1956-61); Joao ...W. Goodman and Juan Riel, eds., Civil Military Relations in Latin America: The Military ana Fower, c. August 1987. Coll, Alberto , and Anthony Arendt

  15. Agriculture, Rio Sao Francisco, Brazil, South America

    Science.gov (United States)

    1988-01-01

    The large field patterns in this view of the Rio Sao Francisco basin, Brazil, South America, (11.5S, 43.5W) indicate a commercial agriculture venture; family subsistence farms are much smaller and laid out in different patterns. Land clearing in Brazil has increased at an alarming rate in recent years and preliminary estimates suggest a 25 to 30% increase in deforestation since 1984. The long term impact on the ecological processes are still unknown.

  16. Geological-uraniferous favourability of South America

    International Nuclear Information System (INIS)

    Stipanicic, P.N.

    1984-01-01

    The South American continent includes several metallogenic provinces some of which have excellent uranium possibilities. Basically, two types of lithological complex have contributed to this favourability: the large Precambrian shields covering about 5,500,000 km 2 and the crystalline Hercynian nesocratons with about 300,000 km 2 as source rocks. Only in Argentina and Brazil has continuous uranium exploration in South America been carried out, with moderate budgets, during the last twenty-five years. In the rest of South America the search for uranium has been performed intermittently and with limited resources. However, during recent years interest has increased and more continuous operation has been recorded in some countries (Bolivia, Colombia, Chile, Peru). It can be estimated that only 20% of the favourable areas have been explored fairly intensively in Argentina and Brazil, the two most advanced uraniferous countries. Nevertheless, the uranium possibilities of South America are proved by the resources of 250,000 t U already defined (in Argentina and Brazil) for the category of production cost below US $130/kg U. The speculative uranium potential of the continent was estimated by the International Uranium Resources Evaluation Project as between 770,000 and 1,500,000 t U. Within the South American geostructural framework, five main uraniferous geological areas have been defined on the basis of the geotectonic evolution of the continent, the succession of sedimentary and magmatic processes, and the participation in them of the endogenous and exogenous phases of the uranium geochemical cycle. In this paper the principal uranium metallogenic models occurring in the above five main areas are studied together with the uranium potential of each area. The possibility of uranium recovery from these sources in relation to the respective costs of production is briefly discussed

  17. Water reuse in South America: A Chilean study

    Energy Technology Data Exchange (ETDEWEB)

    Piero, M.D.

    1998-07-01

    The driest desert in the western hemisphere is the source of the largest and most lucrative copper mining and processing business in South America. The newest, most explosive capitalist economy in South America is fueled by an industry whose ancient water supply is on the verge of collapse. Farther south, a textbook example of 1950's industrial pollution continues to be dumped in the Bio Bio River, the water supply of the country's third largest city. In the temperate Central Valley, public health advisories regularly warn consumers against consuming vegetables irrigated with river water containing raw sewage. In the warm summer months, hepatitis and cholera epidemics are frequent and deadly. In the last 5 years, these areas have initiated major sewage treatment plant and system improvements with significant reuse components. The technologies and reuse applications of reclaimed water that are now being used in Chile are being monitored and evaluated by Peru, Argentina, and Brazil. Major efforts at environmental cleanups are now being combined with new strategies to sue reclaimed water to meet the needs of South American in the 21st century.

  18. Brazilian Hybrid Security in South America

    Directory of Open Access Journals (Sweden)

    Rafael Duarte Villa

    2017-10-01

    Full Text Available Abstract Existing research on security governance in South America functions on dichotomous lines. Analysis of Brazil’s security practices is a case in point. On the one hand, scholars point out the balance of power and hegemonic institutions as the main discourse in the security practices between Brazil and its South American neighbors. On the other hand, some other emphasize the importance of democracy, cooperation on defense and security, and peaceful conflict resolution between states in the region as indicators for the emergence of a security community between Brazil and its neighbors in the South American region. The way in which multiple orders coexist is not given adequate attention in empirical research. This article seeks to overcome this dichotomy. By foregrounding Brazil’s regional security practices, particularly during the Lula and Rousseff administration, I show the hybrid and sometimes ambivalent security governance system in Brazil, where mechanisms of balance of power and security community overlap in important ways.

  19. Zebragryllus Desutter-Grandcolas & Cadena-Casteñada, n.gen. a new Gryllinae genus from Eastern and Western Amazonia, South America (Orthoptera, Grylloidea, Gryllidae).

    Science.gov (United States)

    Desutter-Grandcolas, Laure; Cadena-Castañeda, Oscar J; Jaiswara, Ranjana; Anso, Jeremy

    2014-02-24

    We describe a new genus of grylline cricket, Zebragryllus Desutter-Grandcolas & Cadena-Casteñada n. gen., from the Neotropical Region, using characters of morphology and male genitalia; genitalic characters clearly show that Zebragryllus n. gen. is closely related to Anurogryllus Saussure, 1878. Six species are described as new to science, originax">ting from western (Peru, Colombia) and eastern (French Guiana) Amazonia: Zebragryllus fuscus Desutter-Grandcolas, n. sp., Z. guianensis Desutter-Grandcolas, n. sp., Z. intermedius Desutter-Grandcolas, n. sp., Zebragryllus nauta Desutter-Grandcolas, n. sp., Zebragryllus nouragui Desutter-Grandcolas, n. sp., and Zebragryllus wittoto Desutter-Grandcolas and Cadena-Casteñada, n. sp., type species of the genus. They are characterized by their size, coloration (shining black, most often with white patterns of coloration, hence the genus name), and male and female genitalia. The calling songs of Z. guianensis Desutter-Grandcolas, n. sp., Z. intermedius Desutter-Grandcolas, n. sp., Z. nouragui Desutter-Grandcolas, n. sp., and Z. wittoto Desutter-Grandcolas and Cadena-Casteñada, n. sp. are described. An identification key is proposed for both males and females.

  20. Correlation of uranium geology between South America and Africa

    International Nuclear Information System (INIS)

    1986-01-01

    Acting upon the recommendation of an Advisory Group Meeting held in 1980, the IAEA organized a Working Group on the Correlation of the Uranium Geology between South America and Africa because of the tremendous geological potential for uranium and the interest showed by the Member States of the regions concerned. The report of this Working Group is now presented. The aim of this report is to provide the nuclear industry and, in particular, the countries of the region with a broad but updated outline of current development in the uranium geology and the uranium potential of Africa and South America. The scope is such that it will provide, for those not directly involved in uranium exploration in the area, a general technical summary on the regional geology and tectonics of these two continents in order that the geodynamic setting of their uranium occurrences may be correlated. With respect to the area to be covered and bearing in mind the purpose of this study, the Working Group surveyed the most relevant parts of western Gondwanaland, of which the two continents form a part. The area covered by the report extends from north of the West African Craton and the Guiana Shield to the southern end of South America and Africa; from the Amazonian Province in western Brazil and western Argentina to the central part of the West African Craton, Congo-Kasai Craton. The Andean Chain in South America and the Atlas Mountains in North Africa, which were formed by continental accretion in recent geological time and post-dated the split and drift of the two land masses, were not considered. Some of the inner portions of those cratons distant from the coastlines and for which the correlation features do not apply have also been omitted. However, certain areas of important uranium mineralization outside the main study area have been described in order to offer comparative models for future exploration elsewhere. The subject of the report is discussed under six headings: cratonic areas

  1. Analysis of late Jurassic-recent paleomagnetic data from active plate margins of South America

    Science.gov (United States)

    Beck, Myrl E.

    Paleomagnetic results for rocks of late Mesozoic and Cenozoic age from South America are analyzed and interpreted. Emphasis is placed on the active margins of the continent. Some important conclusions are reached, with varying degrees of certainty: (1) The reference APW path for stable South America is fairly well defined for the Late Jurassic and Cretaceous, and is not much different from the present rotation axis. (2) The so-called "Bolivian orocline" involved counterclockwise rotations in Peru and northernmost Chile and clockwise rotations in Chile south of about latitude 18.5S. These rotations probably are a result of in situ small-block rotations in response to shear, not actual oroclinal bending. (3) The Bonaire block of northern Venezuela and Colombia has been rotated clockwise relative to the stable interior of South America by about 90°. It also seems to have drifted northward relative to the craton by as much as 1600 km. It probably represents a true accreted terrane, one of very few recognized in South America so far. (4) The "Magellanes orocline" at the southern tip of South America apparently involves some counterclockwise rotation of paleomagnetic vectors, but this too is probably the result of distributed shear. (5) Tectonic processes have very thoroughly "rearranged" the rocks making up the active margins of South America. "Rearrange" here denotes displacement of crustal blocks relative to their surroundings, without significant internal deformation By analogy with North America "rearrangement" might entail in situ block rotation, translation of crustal blocks along the continental margin, and accretion of exotic "tectonostratigraphic terranes". However, in western South America "rearrangement" seems to have consisted dominantly of block rotations that were essentially in situ. For the parts of the Andes investigated so far, late Mesozoic and Cenozoic accretion of exotic terranes and large-scale translation of crustal slivers, as found in western

  2. Catalogue of meteorites from South America

    CERN Document Server

    Acevedo, Rogelio Daniel; García, Víctor Manuel

    2014-01-01

    The first Catalogue of Meteorites from South America includes new specimens never previously reported, while doubtful cases and pseudometeorites have been deliberately omitted.The falling of these objects is a random event, but the sites where old meteorites are found tend to be focused in certain areas, e.g. in the deflation surfaces in Chile's Atacama Desert, due to favorable climate conditions and ablation processes.Our Catalogue provides basic information on each specimen like its provenance and the place where it was discovered (in geographic co-ordinates and with illustrative maps), its

  3. Conservation of native Pacific trout diversity in Western North America

    Science.gov (United States)

    Brooke E. Penaluna; Alicia Abadía-Cardoso; Jason B. Dunham; Francisco J. García-Dé León; Robert E. Gresswell; Arturo Ruiz Luna; Eric B. Taylor; Bradley B. Shepard; Robert Al-Chokhachy; Clint C. Muhlfeld; Kevin R. Bestgen; Kevin Rogers; Marco A. Escalante; Ernest R. Keeley; Gabriel M. Temple; Jack E. Williams; Kathleen R. Matthews; Ron Pierce; Richard L. Mayden; Ryan P. Kovach; John Carlos Garza; Kurt D. Fausch

    2016-01-01

    Pacific trout Oncorhynchus spp. in western North America are strongly valued in ecological, socioeconomic, and cultural views, and have been the subject of substantial research and conservation efforts. Despite this, the understanding of their evolutionary histories, overall diversity, and challenges to their conservation is incomplete. We review...

  4. Bark beetle outbreaks in western North America: Causes and consequences

    Science.gov (United States)

    Bentz, Barbara; Logan, Jesse; MacMahon, James A.; Allen, Craig D.; Ayres, Matt; Berg, Edward E; Carroll, Allan; Hansen, Matt; Hicke, Jeff H.; Joyce, Linda A.; Macfarlane, Wallace; Munson, Steve; Negron, Jose; Paine, Tim; Powell, Jim; Raffa, Kenneth; Regniere, Jacques; Reid, Mary; Romme, Bill; Seybold, Steven J.; Six, Diana; Vandygriff, Jim; Veblen, Tom; White, Mike; Witcosky, Jeff; Wood, David J. A.

    2005-01-01

    Since 1990, native bark beetles have killed billions of trees across millions of acres of forest from Alaska to northern Mexico. Although bark beetle infestations are a regular force of natural change in forested ecosystems, several of the current outbreaks, which are occurring simultaneously across western North America, are the largest and most severe in recorded history.

  5. The Dorstenia species (Moraceae) of north-western tropical America

    NARCIS (Netherlands)

    Berg, C.C.; Leeuwen, van R.W.J.

    1982-01-01

    Four new species of Dorstenia are described: D. panamensis C.C. Berg, D. boliviana C.C. Berg, D. peruviana C.C. Berg, and D. belizensis C.C. Berg. A list of and a key to the 21 Dorstenia species distinguished in north-western tropical America are presented, together with synonyms and distributions.

  6. The palms of South America: diversity, distribution and evolutionary history

    Directory of Open Access Journals (Sweden)

    Jean-Christophe Pintaud

    2014-03-01

    Full Text Available This article presents an inventory of South American palms including 457 species and 50 genera. The distribution of palms within seven phytogeographical entities is analyzed. Factors which influence the evolution of palms in South America are discussed.

  7. Hepatitis e virus: Western Cape, South Africa

    NARCIS (Netherlands)

    R.G. Madden (Richie); Wallace, S. (Sebastian); M. Sonderup; Korsman, S. (Stephen); Chivese, T. (Tawanda); Gavine, B. (Bronwyn); Edem, A. (Aniefiok); Govender, R. (Roxy); English, N. (Nathan); Kaiyamo, C. (Christy); Lutchman, O. (Odelia); A.A. Eijck (Annemiek); S.D. Pas (Suzan); Webb, G.W. (Glynn W); Palmer, J. (Joanne); Goddard, E. (Elizabeth); Wasserman, S. (Sean); H.R. Dalton (Harry); C.W. Spearman

    2016-01-01

    textabstractAIM To conduct a prospective assessment of anti-hepatitis E virus (HEV) IgG seroprevalence in the Western Cape Province of South Africa in conjunction with evaluating risk factors for exposure. METHODS Consenting participants attending clinics and wards of Groote Schuur, Red Cross

  8. Seismic hazard, risk, and design for South America

    Science.gov (United States)

    Petersen, Mark D.; Harmsen, Stephen; Jaiswal, Kishor; Rukstales, Kenneth S.; Luco, Nicolas; Haller, Kathleen; Mueller, Charles; Shumway, Allison

    2018-01-01

    We calculate seismic hazard, risk, and design criteria across South America using the latest data, models, and methods to support public officials, scientists, and engineers in earthquake risk mitigation efforts. Updated continental scale seismic hazard models are based on a new seismicity catalog, seismicity rate models, evaluation of earthquake sizes, fault geometry and rate parameters, and ground‐motion models. Resulting probabilistic seismic hazard maps show peak ground acceleration, modified Mercalli intensity, and spectral accelerations at 0.2 and 1 s periods for 2%, 10%, and 50% probabilities of exceedance in 50 yrs. Ground shaking soil amplification at each site is calculated by considering uniform soil that is applied in modern building codes or by applying site‐specific factors based on VS30">VS30 shear‐wave velocities determined through a simple topographic proxy technique. We use these hazard models in conjunction with the Prompt Assessment of Global Earthquakes for Response (PAGER) model to calculate economic and casualty risk. Risk is computed by incorporating the new hazard values amplified by soil, PAGER fragility/vulnerability equations, and LandScan 2012 estimates of population exposure. We also calculate building design values using the guidelines established in the building code provisions. Resulting hazard and associated risk is high along the northern and western coasts of South America, reaching damaging levels of ground shaking in Chile, western Argentina, western Bolivia, Peru, Ecuador, Colombia, Venezuela, and in localized areas distributed across the rest of the continent where historical earthquakes have occurred. Constructing buildings and other structures to account for strong shaking in these regions of high hazard and risk should mitigate losses and reduce casualties from effects of future earthquake strong ground shaking. National models should be developed by scientists and engineers in each country using the best

  9. Alien conifer invasions in South America: short fuse burning?

    CSIR Research Space (South Africa)

    Richardson, DM

    2007-01-01

    Full Text Available conifers has a much shorter history in South America, and invasions are a recent phenomenon. A workshop was convened in Argentina in May 2007 to discuss the rapid emergence of problems with invasive conifers in South America. Workshop delegates agreed that...

  10. Migratory Fishes of South America : Biology, Fisheries, and ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Migratory Fishes of South America : Biology, Fisheries, and Conservation Status. Couverture du livre Migratory Fishes of South America : Biology, Fisheries, and Conservation Status. Directeur(s) : Joachim Carolsfield, Brian Harvey, Carmen Ross et Anton Baer. Maison(s) d'édition : World Fisheries Trust, Banque mondiale, ...

  11. Holocene glacial fluctuations in southern South America

    Science.gov (United States)

    Reynhout, S.; Sagredo, E. A.; Kaplan, M. R.; Aravena, J. C.; Martini, M. A.; Strelin, J. A.; Schaefer, J. M.

    2016-12-01

    Understanding the timing and magnitude of former glacier fluctuations is critical to decipher long-term climatic trends and to unravel both natural cycles and human impact on the current glacial behavior. Despite more than seven decades of research efforts, a unifying model of Holocene glacial fluctuations in Southern South America remains elusive. Here, we present the state-of-the-art regarding the timing of Holocene glacial fluctuation in southern Patagonia-Tierra del Fuego, with a focus on a new generation of high-resolution radiocarbon and 10Be surface exposure dating chronologies. Recently acquired evidence suggest that after receding from advanced Late Glacial positions, Patagonian glaciers were for the most part close to, or even behind, present ice margins during the Early Holocene. On the other hand, emerging chronologies indicate that in some areas there were extensive expansions (century scale?) that punctuated the warm interval. Subsequently, we have evidence of multiple millennial timescale glacial advances starting in the middle Holocene. Several glacial maxima are defined by moraines and other landforms from 7000 years ago to the 19th century, with a gap sometime between 4,500 and 2,500 years ago. The last set of advances began around 800-600 years ago. Although glacial activity is documented in Patagonia at the same time as the European Little Ice Age, the extent of these glacial events are less prominent than those of the mid-Holocene. The causes that may explain these glacial fluctuations remain elusive. Finally, we discuss ongoing efforts to better define the timing and extent of Holocene glaciations in southern South America, and to establish the basis to test competing hypothesis of regional Holocene climate variability.

  12. Taxonomy of interstate conflicts: is South America a peaceful region?

    Directory of Open Access Journals (Sweden)

    Tássio Franchi

    2017-08-01

    Full Text Available This article revisits theoretical efforts to classify interstate conflicts. It analyses South America and discuss the adequacy of influential interpretations about the intensity of interstate conflicts in the region as compared to global or other regions ones. The literature takes for granted that South America is a peaceful region. Such interpretation results from the indicators adopted. We argue that traditional indicators do not fully capture latent tensions and the actual level of conflicts in the region. The article suggests an alternative taxonomy that better fits the South America context and argues that a research agenda on the extent and nature of interstate conflics is needed.

  13. Shifting Pacific storm tracks as stressors to ecosystems of western North America.

    Science.gov (United States)

    Dannenberg, Matthew P; Wise, Erika K

    2017-11-01

    Much of the precipitation delivered to western North America arrives during the cool season via midlatitude Pacific storm tracks, which may experience future shifts in response to climate change. Here, we assess the sensitivity of the hydroclimate and ecosystems of western North America to the latitudinal position of cool-season Pacific storm tracks. We calculated correlations between storm track variability and three hydroclimatic variables: gridded cool-season standardized precipitation-evapotranspiration index, April snow water equivalent, and water year streamflow from a network of USGS stream gauges. To assess how historical storm track variability affected ecosystem processes, we derived forest growth estimates from a large network of tree-ring widths and land surface phenology and wildfire estimates from remote sensing. From 1980 to 2014, cool-season storm tracks entered western North America between approximately 41°N and 53°N. Cool-season moisture supply and snowpack responded strongly to storm track position, with positive correlations to storm track latitude in eastern Alaska and northwestern Canada but negative correlations in the northwestern U.S. Ecosystems of the western United States were greener and more productive following winters with south-shifted storm tracks, while Canadian ecosystems were greener in years when the cool-season storm track was shifted to the north. On average, larger areas of the northwestern United States were burned by moderate to high severity wildfires when storm tracks were displaced north, and the average burn area per fire also tended to be higher in years with north-shifted storm tracks. These results suggest that projected shifts of Pacific storm tracks over the 21st century would likely alter hydroclimatic and ecological regimes in western North America, particularly in the northwestern United States, where moisture supply and ecosystem processes are highly sensitive to the position of cool-season storm tracks.

  14. Feline Immunodeficiency Virus in South America

    Directory of Open Access Journals (Sweden)

    Bruno M. Teixeira

    2012-03-01

    Full Text Available The rapid emergence of AIDS in humans during the period between 1980 and 2000 has led to extensive efforts to understand more fully similar etiologic agents of chronic and progressive acquired immunodeficiency disease in several mammalian species. Lentiviruses that have gene sequence homology with human immunodeficiency virus (HIV have been found in different species (including sheep, goats, horses, cattle, cats, and several Old World monkey species. Lentiviruses, comprising a genus of the Retroviridae family, cause persistent infection that can lead to varying degrees of morbidity and mortality depending on the virus and the host species involved. Feline immunodeficiency virus (FIV causes an immune system disease in domestic cats (Felis catus involving depletion of the CD4+ population of T lymphocytes, increased susceptibility to opportunistic infections, and sometimes death. Viruses related to domestic cat FIV occur also in a variety of nondomestic felids. This is a brief overview of the current state of knowledge of this large and ancient group of viruses (FIVs in South America.

  15. The buffalo in Southern South America

    Directory of Open Access Journals (Sweden)

    M. Zava

    2010-02-01

    Full Text Available The number of buffaloes in the American continent is growing at the explosive rate of 12.7 % a year, well above all other continents. Within this context the different situations of the southern part of South America are described, those countries that two hundred years ago were part of the River Plate Viceroyship and the Chile General Command, both of them part of the Spanish empire. The first steps of buffaloes in Paraguay, Bolivia and Uruguay. The expansion of buffaloes in Argentina and their recent start up in Chile. The production systems in the region are described, principally Argentina and Paraguay. The major changes and expansion of agriculture in Argentina are displacing cattle production from the North towards the Tropics, where buffalo has proven to be very superior in productivity compared to cattle production thanks to its very good adaptation to the local conditions. In Paraguay, a totally subtropical country, something very similar is happening. Paraguay has consolidated its sales of buffalo hides and beef. Argentina is well on its way to having a very efficient buffalo beef marketing competing with cattle of the highest quality. Buffalo milk production is still not mature in these countries, although there are several projects underway in Uruguay, Bolivia and Argentina.

  16. Feline immunodeficiency virus in South America.

    Science.gov (United States)

    Teixeira, Bruno M; Hagiwara, Mitika K; Cruz, Juliano C M; Hosie, Margaret J

    2012-03-01

    The rapid emergence of AIDS in humans during the period between 1980 and 2000 has led to extensive efforts to understand more fully similar etiologic agents of chronic and progressive acquired immunodeficiency disease in several mammalian species. Lentiviruses that have gene sequence homology with human immunodeficiency virus (HIV) have been found in different species (including sheep, goats, horses, cattle, cats, and several Old World monkey species). Lentiviruses, comprising a genus of the Retroviridae family, cause persistent infection that can lead to varying degrees of morbidity and mortality depending on the virus and the host species involved. Feline immunodeficiency virus (FIV) causes an immune system disease in domestic cats (Felis catus) involving depletion of the CD4+ population of T lymphocytes, increased susceptibility to opportunistic infections, and sometimes death. Viruses related to domestic cat FIV occur also in a variety of nondomestic felids. This is a brief overview of the current state of knowledge of this large and ancient group of viruses (FIVs) in South America.

  17. Icacinaceae from the eocene of Western North America.

    Science.gov (United States)

    Allen, Sarah E; Stull, Gregory W; Manchester, Steven R

    2015-05-01

    The Icacinaceae are a pantropical family of trees, shrubs, and climbers with an extensive Paleogene fossil record. Our improved understanding of phylogenetic relationships within the family provides an excellent context for investigating new fossil fruit and leaf material from the Eocene of western North America. We examined fossils from early and middle Eocene sediments of western Wyoming, northeastern Utah, northwestern Colorado, and Oregon and compared them with extant species of Iodes and other icacinaceous genera as well as previously described fossils of the family. Three new fossil species are described, including two based on endocarps (Iodes occidentalis sp. nov. and Icacinicaryites lottii sp. nov.) and one based on leaves (Goweria bluerimensis sp. nov.). The co-occurrence of I. occidentalis and G. bluerimensis suggests these might represent detached organs of a single species. A new genus, Biceratocarpum, is also established for morphologically distinct fossil fruits of Icacinaceae previously placed in Carpolithus. Biceratocarpum brownii gen. et comb. nov. resembles the London Clay species "Iodes" corniculata in possessing a pair of subapical protrusions. These fossils increase our knowledge of Icacinaceae in the Paleogene of North America and highlight the importance of the Northern Hemisphere in the early diversification of the family. They also document interchange with the Eocene flora of Europe and biogeographic connections with modern floras of Africa and Asia, where Icacinaceae are diverse today. The present-day restriction of this family to tropical regions offers ecological implications for the Eocene floras in which they occur. © 2015 Botanical Society of America, Inc.

  18. Ecosystem Demography Model: Scaling Vegetation Dynamics Across South America

    Data.gov (United States)

    National Aeronautics and Space Administration — This model product contains the source code for the Ecosystem Demography Model (ED version 1.0) as well as model input and output data for a portion of South America...

  19. Invasion by a Japanese marine microorganism in western North America

    Science.gov (United States)

    McGann, M.; Sloan, D.; Cohen, A.N.

    2000-01-01

    The earliest record in western North America of Trochammina hadai Uchio, a benthic foraminifer common in Japanese estuaries, is from sediment collected in Puget Sound in 1971. It was first found in San Francisco Bay in sediment samples taken in 1983, and since 1986 has been collected at 91% of the sampled sites in the Bay, constituting up to 93% of the foraminiferal assemblage at individual sites. The species is also present in recent sediment samples from 12 other sites along the west coast of North America. The evidence indicates that T. hadai is a recent introduction to San Francisco Bay, and is probably also not native to the other North American sites. Trochammina hadai was probably transported from Japan in ships' ballast tanks, in mud associated with anchors, or in sediments associated with oysters imported for mariculture. Its remarkable invasion of San Francisco Bay suggests the potential for massive, rapid invasions by other marine microorganisms.

  20. Introduction: seismology and earthquake engineering in Central and South America.

    Science.gov (United States)

    Espinosa, A.F.

    1983-01-01

    Reports the state-of-the-art in seismology and earthquake engineering that is being advanced in Central and South America. Provides basic information on seismological station locations in Latin America and some of the programmes in strong-motion seismology, as well as some of the organizations involved in these activities.-from Author

  1. South America's energy integration overshadows Venezuela-US confrontational posture

    International Nuclear Information System (INIS)

    Abrantes, Dayse

    2006-01-01

    Venezuela's plans of a 10 000 km gas pipeline project spanning Latin America is presented. A brief analysis of Venezuela's petroleum industry is provided. President Hugo Chavez' main ambitions include reducing oil sales to the USA and to spark South America's energy integration

  2. Paleohydrology Reconstruction of the Tropical South America for the Past 1.6 Million Years.

    Science.gov (United States)

    Oliveira, A. S.; Baker, P. A.; Silva, C. G.; Dwyer, G. S.; Rigsby, C. A.; Chiessi, C. M.

    2016-12-01

    The western Atlantic equatorial margin has been recognized as an important part of global climate change. It is responsible for the transfer of moisture to South America and, heat and fresh water to the northern hemisphere. It might hold answers to past and present global climate. We reconstructed the last 1.6 million years of the paleoclimatic record of the Tropical South American to assess a long period of oceanic and atmospheric variability, which still remains unknown to science. Paleoclimate reconstructions of the Tropical South American are determined on a sediment core located on the Brazilian continental slope. High-resolution XRF analyses of Fe, Ti, K and Ca are used to define the paleohydrologic evolution. Here we present elemental ratios of Ti/Ca and Fe/K, to determine variability in Tropical South America. Differences in sediment input observed on Fe/K and Ti/Ca ratios suggest periods of increased chemical weathering and precipitation. Comparison of our data with the Cariaco basin Molybdenum (Mo) records, suggests that the Intertropical Convergence Zone (ITCZ) is triggering wet periods on Tropical South America, distinguishing a clear North-South anti-phase over the last 600 ka. Southward displacement of the ITCZ in the Mid-Pleistocene Transition, indicates changes in the variability mode of the ITCZ N-S excursion, modulating the precipitation over Tropical South America. We also show that extensive northward migration of Antarctic Polar Front induces a drastic change in the Tropical South America hydrological system, triggering long periods of drought, potentially driven by cooler sea surface temperature of the South Atlantic. This study is funded by Capes- IODP 38/2014 and the Duke University.

  3. Conservation of native Pacific trout diversity in western North America

    Science.gov (United States)

    Penaluna, Brooke E.; Abadía-Cardoso, Alicia; Dunham, Jason B.; García de León, Francisco J; Gresswell, Robert E.; Luna, Arturo Ruiz; Taylor, Eric B.; Shepard, Bradley B.; Al-Chokhachy, Robert K.; Muhlfeld, Clint C.; Bestgen, Kevin R.; Rogers, Kevin H.; Escalante, Marco A; Keeley, Ernest R; Temple, Gabriel; Williams, Jack E.; Matthews, Kathleen; Pierce, Ron; Mayden, Richard L.; Kovach, Ryan; Garza, John Carlos; Fausch, Kurt D.

    2016-01-01

    Pacific trout Oncorhynchus spp. in western North America are strongly valued in ecological, socioeconomic, and cultural views, and have been the subject of substantial research and conservation efforts. Despite this, the understanding of their evolutionary histories, overall diversity, and challenges to their conservation is incomplete. We review the state of knowledge on these important issues, focusing on Pacific trout in the genus Oncorhynchus. Although most research on salmonid fishes emphasizes Pacific salmon, we focus on Pacific trout because they share a common evolutionary history, and many taxa in western North America have not been formally described, particularly in the southern extent of their ranges. Research in recent decades has led to the revision of many hypotheses concerning the origin and diversification of Pacific trout throughout their range. Although there has been significant success at addressing past threats to Pacific trout, contemporary and future threats represented by nonnative species, land and water use activities, and climate change pose challenges and uncertainties. Ultimately, conservation of Pacific trout depends on how well these issues are understood and addressed, and on solutions that allow these species to coexist with a growing scope of human influences.

  4. Highly specialized mammalian skulls from the Late Cretaceous of South America.

    Science.gov (United States)

    Rougier, Guillermo W; Apesteguía, Sebastián; Gaetano, Leandro C

    2011-11-02

    Dryolestoids are an extinct mammalian group belonging to the lineage leading to modern marsupials and placentals. Dryolestoids are known by teeth and jaws from the Jurassic period of North America and Europe, but they thrived in South America up to the end of the Mesozoic era and survived to the beginnings of the Cenozoic. Isolated teeth and jaws from the latest Cretaceous of South America provide mounting evidence that, at least in western Gondwana, dryolestoids developed into strongly endemic groups by the Late Cretaceous. However, the lack of pre-Late Cretaceous dryolestoid remains made study of their origin and early diversification intractable. Here we describe the first mammalian remains from the early Late Cretaceous of South America, including two partial skulls and jaws of a derived dryolestoid showing dental and cranial features unknown among any other group of Mesozoic mammals, such as single-rooted molars preceded by double-rooted premolars, combined with a very long muzzle, exceedingly long canines and evidence of highly specialized masticatory musculature. On one hand, the new mammal shares derived features of dryolestoids with forms from the Jurassic of Laurasia, whereas on the other hand, it is very specialized and highlights the endemic, diverse dryolestoid fauna from the Cretaceous of South America. Our specimens include only the second mammalian skull known for the Cretaceous of Gondwana, bridging a previous 60-million-year gap in the fossil record, and document the whole cranial morphology of a dryolestoid, revealing an unsuspected morphological and ecological diversity for non-tribosphenic mammals.

  5. New views on American colonization: critical tests from South America

    Directory of Open Access Journals (Sweden)

    O'Rourke, Dennis

    2007-01-01

    Full Text Available The traditional view of colonization of the Americas as a migration across Beringia and subsequent dispersal southward following the last glacial maximum is being increasingly questioned. In North America, archaeological links to Siberia are tenuous and genetic data are more consistent with an earlier entry of people into the Americas, from Central rather than Northeast Siberia. An entry of populations into the Americas prior to the last glacial maximum forces a reconsideration not only of timing, but also geographic points of entry and speed of dispersal, based on ecological theory. A number of emerging alternative hypotheses on the colonization of the Americas predict early entry and dispersal of people into South America - earlier than, or coeval with, initial dispersal in North America. The study of genetic, morphological, and archaeological variation across South America is critical to testing these new, alternative hypotheses of Native American origins. I will review the evidence for emerging, alternative views of American Colonization, and suggest ways in which data from South American populations and prehistory will be crucial in testing them.

  6. Global evolution of Equidae and Gomphotheriidae from South America.

    Science.gov (United States)

    Prado, José L; Alberdi, María T

    2014-08-01

    The contemporary South American mammalian communities were determined by the emergence of the Isthmus of Panama and by the profound climatic oscillations during the Pleistocene. Horses and gomphotheres were 2 very conspicuous groups of immigrant mammals from North America that arrived in South America during the Pleistocene. The present study compiles updated data on the phylogeny, systematics and ecology of both groups in South America. The horses in South America are represented by 2 genera, Hippidion and Equus, as are the gomphotheres, represented by Cuvieronius and Stegomastodon. Both genera of horses include small (Hippidion devillei, H. saldiasi, E. andium and E. insulatus) and large forms (Equus neogeus and H. principale), which dispersed into South America using 2 different routes. The possible model for this dispersion indicates that the small forms used the Andes corridor, while larger horses dispersed through the eastern route and through some coastal areas. In the case of gomphotheres, Cuvieronius and Stegomastodon reached South America in 2 independent dispersal events, and Cuvieronius dispersed across the Andean corridor, while large Stegomastodon spread along the eastern route. Horses and gomphotheres present values of δ(13) C from woodlands to C4 grasslands. Hippidion present lower values of δ(13) C than Equus in the late Pleistocene, whereas the gomphotheres diverge from value of δ(18) O, reflecting that Cuvieronius inhabited the Andean corridor and Stegomastodon dispersed through eastern plains. The gomphothere and horse species recorded in South America became extinct around the time that humans arrived. © 2013 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  7. Energy security in South America and Southern Africa: synthesis report

    International Nuclear Information System (INIS)

    Kiratu, Sheila

    2011-01-01

    In developing countries, the ability to provide adequate and reliable energy supplies is a key to sustainable economic development. The aim of this report is to study the energy supply security in both Southern Africa and South America and how these regions can participate in the international effort to combat climate change. This report showed that South Africa's energy sector mostly relies on carbon intensive coal while Brazil is mainly supplied by hydroelectricity. It was found that in both countries energy needs will increase significantly due to rising demand both internally and at a regional scale. However it was also shown that both Southern Africa and South America have important hydro, solar and wind renewable resources which could enhance their electricity security while minimizing their environmental impacts. This study demonstrated that Southern Africa and South America can enhance their electricity security through the use of renewable energies but that technology and financing is needed to develop the sector.

  8. Phylodynamic analysis of avian infectious bronchitis virus in South America.

    Science.gov (United States)

    Marandino, Ana; Pereda, Ariel; Tomás, Gonzalo; Hernández, Martín; Iraola, Gregorio; Craig, María Isabel; Hernández, Diego; Banda, Alejandro; Villegas, Pedro; Panzera, Yanina; Pérez, Ruben

    2015-06-01

    Infectious bronchitis virus (IBV) is a coronavirus of chickens that causes great economic losses to the global poultry industry. The present study focuses on South American IBVs and their genetic relationships with global strains. We obtained full-length sequences of the S1 coding region and N gene of IBV field isolates from Uruguay and Argentina, and performed Phylodynamic analysis to characterize the strains and estimate the time of the most recent common ancestor. We identified two major South American genotypes, which were here denoted South America I (SAI) and Asia/South America II (A/SAII). The SAI genotype is an exclusive South American lineage that emerged in the 1960s. The A/SAII genotype may have emerged in Asia in approximately 1995 before being introduced into South America. Both SAI and A/SAII genotype strains clearly differ from the Massachusetts strains that are included in the vaccine formulations being used in most South American countries. © 2015 The Authors.

  9. Potential for small-diameter sawtimber utilization by the current sawmill industry in western North America.

    Science.gov (United States)

    Francis G. Wagner; Charles E. Keegan; Roger D. Fight; Susan. Willits

    1998-01-01

    New silvicultural prescriptions for ecosystem management on both public and private timberlands in western North America will likely result in an influx of relatively small-diameter sawtimber for processing. Since sawmills currently process a majority of sawtimber harvested in western North America (more than 80% in some regions), this study concentrated on...

  10. Projected future suitable habitat and productivity of Douglas-fir in western North America

    Science.gov (United States)

    Aaron R. Weiskittel; Nicholas L. Crookston; Gerald E. Rehfeldt

    2012-01-01

    Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) is one of the most common and commercially important species in western North America. The species can occupy a range of habitats, is long-lived (up to 500 years), and highly productive. However, the future of Douglas-fir in western North America is highly uncertain due to the expected changes in climate conditions....

  11. Environmental pollution research in South America

    International Nuclear Information System (INIS)

    Miguel, A.H.

    1991-01-01

    This article provides and account of published research in environmental pollution carried out in South American institutions within the past 10 years. Because of the broadness of the topic, the continental dimensions of the assignment, and limitations of space and time, the article focuses on environmental research related to air, water, food, and soil. Thus, it is not a complete record, but rather a sample of published pollution research activities. The information here was obtained primarily from Dialog's electronic search of the Pollution Abstracts Database. The article also identifies other environmental problems that need the attention of South American researchers

  12. Greening South America, one business at a time | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2016-09-06

    Sep 6, 2016 ... An employee at a print shop in Peru carries a stack of paper on his head ... medium-sized businesses across South America are learning more about. ... The 48th Asian Development Bank (ADB) annual meeting was held in ...

  13. Timber production in selectively logged tropical forests in South America.

    Science.gov (United States)

    Michael Keller; Gregory P. Asner; Geoffrey Blate; Frank McGlocklin; John Merry; Marielos Peña-Claros; Johan Zweede

    2007-01-01

    Selective logging is an extensive land-use practice in South America. Governments in the region have enacted policies to promote the establishment and maintenance of economically productive and sustainable forest industries.However, both biological and policy constraints threaten to limit the viability of the industry over the long term.Biological constraints, such as...

  14. Asia and South America: A Quasi-Common Economy Approach

    OpenAIRE

    Canuto, Otaviano; Sharma, Manu

    2011-01-01

    The Asian style of regional integration may be seen as a 'quasi-common economy' that eschews a formal linkup in political or monetary terms, but manages to generate similar results by strong physical integration and distributed chains of production and service delivery. This note proposes the Asian quasi-common economy as a benchmark for South America's regional integration efforts because...

  15. Migratory Fishes of South America: Biology, Fisheries, and ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2004-01-01

    Jan 1, 2004 ... Fish species that migrate within the great rivers of South America support important local fisheries but are little known outside their native range. This book represents the first collection of the work of local scientific experts on these remarkable fish. The authors cover the Upper Paraná, Paraguay-Paraná, ...

  16. Living in South America. Young Discovery Library: No. 28.

    Science.gov (United States)

    Henry-Biabaud, Chantal

    Part of an international series of amply illustrated, colorful, small-sized books for children ages 5 to 10, this volume is designed to enhance learning and serve as an educational resource. The history, geography, customs, people, flora, and fauna of the countries of South America are described. Illustrations appear throughout the book. (DB)

  17. LEONA for TLE and HEET Research in South America

    Science.gov (United States)

    São Sabbas, F.; Souza, J. R. D.; Guerra, E. M.; Filho, A. C. J.; Galvão, R. M. O.; Branco, R.; Kherani, E. A.; Naccarato, K. P.; Federico, C. A.; Pazianotto, M. T.; Gatto, R. C.; Cisotto, M. V.; Brito, A. F. D.; Fontes, N. R.; Camargo, I. H.; Silva, A. L. G. D.

    2017-12-01

    In 2014 the core of LEONA, which is the "Transient Luminous Event and Thunderstorm High Energy Emission Collaborative Network in Latin America", was established in Brazil with 4 ground stations equipped to perform Transient Luminous Events - TLEs. This year a neutron detector was also installed to collect data on neutron flashes produced by lightning and thunderstorms themselves. Neutrons are one of the several types of High Energy Emissions from Thunderstorms - HEETs. The TLE stations are operated remotely via internet, by users logged in LEONA website, and the HEET station is continuously and automatically operated. Now a proposal to expand LEONA to have 12 TLE ground stations, 2 HEET ground stations (for neutrons, gamma and X rays) and 1 HEET mobile station (for gamma and X rays) is currently under evaluation by the Brazilian São Paulo Research Foundation - FAPESP, and if funded will start to be carried out in early 2018. The expanded version of LEONA will cover the Central Region of South America, including Southeast and Southern Brazil, Northern Argentina, Paraguay and Uruguay, which compose the most electrically active Region of South America. It will also have one TLE station in the Amazon and Northeast Regions of Brazil. South America is one of the most active thunderstorm regions of the world, with extremely large and long lived thunderstorms. Due to the South Atlantic Magnetic Anomaly - SAMA, covering most of its territory, scientific satellites routinely turn off their equipment while flying over South America, therefore a ground network like LEONA is the only way to make consistent long term measurements of TLEs and HEET in this important region of the world. This paper will present LEONA in detail, its current operational status and its expansion plan over the next 4 years. It will also highlight the main results of the different TLE observations performed from Brazil up to date by the Atmospheric and Space Electrodynamical Coupling - ACATMOS group at

  18. Southeast Asia-South America interregionalism: a complement to bilateralism

    Directory of Open Access Journals (Sweden)

    M. Florencia Rubiolo

    2016-09-01

    Full Text Available Inter-state relations between the countries of South America and Southeast Asia (SEA have blossomed in the past 15 years, arousing the interest of a growing number of academics. Their interregional relations, on the other hand, have been less well examined, due, probably, to the fact that their development remains incipient, as well as sporadic and poorly institutionalised. The starting point for this work is the premise that in the case of non-central regions this level of connection complements and works as a feedback mechanism for bilateral links and encourages State-State, State-region and region-region rapprochement. It introduces notions of South American regionalism and centres on concepts related to non-triadic interregionalism in the initiatives between South America and SEA since 1999.

  19. Malaria in South America: a drug discovery perspective.

    Science.gov (United States)

    Cruz, Luiza R; Spangenberg, Thomas; Lacerda, Marcus V G; Wells, Timothy N C

    2013-05-24

    The challenge of controlling and eventually eradicating malaria means that new tools are urgently needed. South America's role in this fight spans both ends of the research and development spectrum: both as a continent capable of discovering and developing new medicines, and also as a continent with significant numbers of malaria patients. This article reviews the contribution of groups in the South American continent to the research and development of new medicines over the last decade. Therefore, the current situation of research targeting malaria control and eradication is discussed, including endemicity, geographical distribution, treatment, drug-resistance and diagnosis. This sets the scene for a review of efforts within South America to discover and optimize compounds with anti-malarial activity.

  20. Oil supply in Central and South America

    International Nuclear Information System (INIS)

    Aguilera, Roberto F.

    2009-01-01

    This paper estimates a cumulative supply curve for conventional oil in the Central and South American (CSA) region. The curve includes volumes from provinces not previously assessed by other organizations, as well as reserve growth. Volumes for the previously unassessed provinces are estimated using a variable shape distribution (VSD) model. Then the volumes are allocated to CSA countries based on each country's share of proved reserves. Figures provided by the cumulative supply curve are stock variables for all time, unlike the traditional supply curve where they are flow variables that can continue from one period to the next. In this study, the fixed stock approach is used since it provides practical information with respect to the concerns that some have expressed about oil scarcity in the near future. Results indicate that Central and South American oil is more abundant than often assumed, and can be produced at costs below current market oil prices, and substantially below mid-2008 prices.

  1. Updated Estimates of Glacier Mass Change for Western North America

    Science.gov (United States)

    Menounos, B.; Gardner, A. S.; Howat, I.; Berthier, E.; Dehecq, A.; Noh, M. J.; Pelto, B. M.

    2017-12-01

    Alpine glaciers are critical components in Western North America's hydrologic cycle. We use varied remotely-sensed datasets to provide updated mass change estimates for Region 2 of the Randolf Glacier Inventory (RGI-02 - all North American glaciers outside of Alaska). Our datasets include: i) aerial laser altimetry surveys completed over many thousands of square kilometers; and ii) multiple Terabytes of high resolution optical stereo imagery (World View 1-3 and Pleiades). Our data from the period 2014-2017 includes the majority of glaciers in RGI-02, specifically those ice masses in the Rocky Mountains (US and Canada), Interior Ranges in British Columbia and the Cascade Mountains (Washington). We co-registered and bias corrected the recent surface models to the Shuttle Radar Topographic Mapping (SRTM) data acquired in February, 2000. In British Columbia, our estimates of mass change are within the uncertainty estimates obtained for the period 1985-2000, but estimates from some regions indicate accelerated mass loss. Work is also underway to update glacier mass change estimates for glaciers in Washington and Montana. Finally, we use re-analysis data (ERA interim and ERA5) to evaluate the meteorological drivers that explain the temporal and spatial variability of mass change evident in our analysis.

  2. Mercury and methylmercury in aquatic sediment across western North America

    Science.gov (United States)

    Fleck, Jacob; Marvin-DiPasquale, Mark C.; Eagles-Smith, Collin A.; Ackerman, Joshua T.; Lutz, Michelle A; Tate, Michael T.; Alpers, Charles N.; Hall, Britt D.; Krabbenhoft, David P.; Eckley, Chris S.

    2016-01-01

    Large-scale assessments are valuable in identifying primary factors controlling total mercury (THg) and monomethyl mercury (MeHg) concentrations, and distribution in aquatic ecosystems. Bed sediment THg and MeHg concentrations were compiled for > 16,000 samples collected from aquatic habitats throughout the West between 1965 and 2013. The influence of aquatic feature type (canals, estuaries, lakes, and streams), and environmental setting (agriculture, forest, open-water, range, wetland, and urban) on THg and MeHg concentrations was examined. THg concentrations were highest in lake (29.3 ± 6.5 μg kg− 1) and canal (28.6 ± 6.9 μg kg− 1) sites, and lowest in stream (20.7 ± 4.6 μg kg− 1) and estuarine (23.6 ± 5.6 μg kg− 1) sites, which was partially a result of differences in grain size related to hydrologic gradients. By environmental setting, open-water (36.8 ± 2.2 μg kg− 1) and forested (32.0 ± 2.7 μg kg− 1) sites generally had the highest THg concentrations, followed by wetland sites (28.9 ± 1.7 μg kg− 1), rangeland (25.5 ± 1.5 μg kg− 1), agriculture (23.4 ± 2.0 μg kg− 1), and urban (22.7 ± 2.1 μg kg− 1) sites. MeHg concentrations also were highest in lakes (0.55 ± 0.05 μg kg− 1) and canals (0.54 ± 0.11 μg kg− 1), but, in contrast to THg, MeHg concentrations were lowest in open-water sites (0.22 ± 0.03 μg kg− 1). The median percent MeHg (relative to THg) for the western region was 0.7%, indicating an overall low methylation efficiency; however, a significant subset of data (n > 100) had percentages that represent elevated methylation efficiency (> 6%). MeHg concentrations were weakly correlated with THg (r2 = 0.25) across western North America. Overall, these results highlight the large spatial variability in sediment THg and MeHg concentrations throughout western North America and underscore the important roles that landscape and land

  3. Calculating investment potential in South America

    International Nuclear Information System (INIS)

    Smith, J.L.

    1995-01-01

    Taxes and licensing provisions typically increase overall costs for private investors, and therefore impede private investment. In addition, the design and structure of tax systems in each country affect the extent to which financial risks are borne by private investors, rather than by the host government. Tax systems that increase perceived financial risks stemming from unpredictable oil prices, development costs and physical characteristics of undiscovered or undeveloped oil fields raise further impediments to private investment. This analysis focuses on both aspects of the investment climate--risk and return--and the way that investment incentives within three South American countries are influenced by tax and licensing regimes

  4. Lynch syndrome in South America: past, present and future.

    Science.gov (United States)

    Vaccaro, Carlos A; Sarroca, Carlos; Rossi, Benedito; Lopez-Kostner, Francisco; Dominguez, Mev; Calo, Natalia Causada; Cutait, Raul; Valle, Adriana Della; Nuñez, Lina; Neffa, Florencia; Alvarez, Karin; Gonzalez, Maria Laura; Kalfayan, Pablo; Lynch, Henry T; Church, James

    2016-07-01

    After decades of unawareness about Lynch syndrome, the medical community in South America is increasingly interested and informed. The visits and support of mentors like H. T. Lynch had been crucial to this awakening. Several countries have at least one registry with skilled personnel in genetic counseling and research. However, this only represents a very restricted resource for the region. According to the GETH, there are 27 hereditary cancer care centers in South America (21 in Brazil, 3 in Argentina, 1 in Uruguay, 1 in Chile and 1 in Peru). These registries differ in fundamental aspects of function, capabilities and funding, but are able to conduct high quality clinical, research and educational activities due to the dedication and personal effort of their members, and organizational support. More support from the governments as well as the participation of the community would boost the initiatives of people leading these groups. Meantime, the collaboration among the South American registries and the involvement of registries and leaders from developed countries will allow to maximize the efficiency in caring for affected patients and their families. The aim of this article is to describe how the knowledge of LS began to be spread in South America, how the first registries were organized and to summarize the current state of progress. In addition, we will provide an update of the clinical and molecular findings in the region.

  5. Protoparmelia capitata (Ascomycota: Parmeliaceae: new record for South America

    Directory of Open Access Journals (Sweden)

    André Aptroot

    2013-09-01

    Full Text Available The sterile corticolous crustose lichen Protoparmelia capitata (Ascomycota: Parmeliaceae, recently described for southeastern North America, is reported as a new record for South America in the Serra da Jiboia mountain range, near the municipality of Santa Teresinha, in the state of Bahia, in northeastern Brazil. This species is locally common and is probably closely related to P. isidiata, which has the same pigmentation and medullary chemistry, P. capitata differing from P. isidiata in that the former features soredia rather than isidia.

  6. Domestication and human demographic history in South America.

    Science.gov (United States)

    Perez, S Ivan; Postillone, María Bárbara; Rindel, Diego

    2017-05-01

    The early groups of hunter-gatherers who peopled South America faced significant ecological changes in their trophic niche for a relatively short period after the initial peopling. In particular, the incorporation of cultigens during the Holocene led to a wider trophic niche and probably to an increased carrying capacity of the environment. Here, we study the relationship between the incorporation of domestic resources during the Holocene and the demographic dynamics of human populations at a regional scale in South America. We employ mitochondrial DNA (mtDNA), radiocarbon data and Bayesian methods to estimate differences in population size, human occupation and explore the demographic changes of human populations in three regions (i.e., South-Central Andes, Northwest, and South Patagonia). We also use archaeological evidence to infer the main diet changes in these regions. The absolute population size during the later Late Holocene was fifteen times larger in the South-Central Andes than in Northwest Patagonia, and two times larger in the latter region than in South Patagonia. The South-Central Andes display the earlier and more abrupt population growth, beginning about 9000 years BP, whereas Northwest Patagonia exhibits a more slow growth, beginning about 7000-7500 years BP. South Patagonia represents a later and slower population increase. In this work we uncovered a well-supported pattern of the demographic change in the populations from South-Central Andes and Patagonia, obtained on the basis of different data and quantitative approaches, which suggests that the incorporation of domestic resources was paramount for the demographic expansion of these populations during the Holocene. © 2017 Wiley Periodicals, Inc.

  7. Knowledge exchange for climate adaptation planning in western North America

    Science.gov (United States)

    Garfin, Gregg; Orr, Barron

    2015-04-01

    In western North America, the combination of sustained drought, rapid ecosystem changes, and land use changes associated with urban population growth has motivated concern among ecosystem managers about the implications of future climate changes for the landscapes which they manage. Through literature review, surveys, and workshop discussions, we assess the process of moving from concern, to planning, to action, with an emphasis on questions, such as: What are the roles of boundary organizations in facilitating knowledge exchange? Which practices lead to effective interactions between scientists, decision-makers, and knowledge brokers? While there is no "one size fits all" science communication method, the co-production of science and policy by research scientists, science translators, and decision-makers, as co-equals, is a resource intensive, but effective practice for moving adaptation planning forward. Constructive approaches make use of alliances with early adopters and opinion leaders, and make strong communication links between predictions, impacts and solutions. Resource managers need information on the basics of regional climate variability and global climate change, region-specific projections of climate changes and impacts, frank discussion of uncertainties, and opportunities for candid exploration of these topics with peers and subject experts. Research scientists play critical roles in adaptation planning discussions, because they assist resource managers in clarifying the cascade of interactions leading to potential impacts and, importantly, because decision-makers want to hear the information straight from the scientists conducting the research, which bolsters credibility. We find that uncertainty, formerly a topic to avoided, forms the foundation for constructive progress in adaptation planning. Candid exploration of the array of uncertainties, including those due to modeling, institutional, policy and economic factors, with practitioners, science

  8. South Africa : an opportunity for Western Europe ?

    International Nuclear Information System (INIS)

    Fischer, D.

    1989-01-01

    Of the six threshold countries (Argentina, Brazil, India, Israel, Pakistan, and South Africa), South Africa is the only one that, by a judicious application of pressures and incentives might be induced to accede the Non-Proliferation Treaty. There are several reasons for this, which derive chiefly from South Africa's political isolation and economic vulnerability and the absence of any credible military threat from beyond the country's borders. (author)

  9. Saver.net lidar network in southern South America

    Directory of Open Access Journals (Sweden)

    Ristori Pablo

    2018-01-01

    Full Text Available The South American Environmental Risk Management Network (SAVER-Net is an instrumentation network, mainly composed by lidars, to provide real-time information for atmospheric hazards and risk management purposes in South America. This lidar network have been developed since 2012 and all its sampling points are expected to be fully implemented by 2017. This paper describes the network’s status and configuration, the data acquisition and processing scheme (protocols and data levels, as well as some aspects of the scientific networking in Latin American Lidar Network (LALINET. Similarly, the paper lays out future plans on the operation and integration to major international collaborative efforts.

  10. Saver.net lidar network in southern South America

    Science.gov (United States)

    Ristori, Pablo; Otero, Lidia; Jin, Yoshitaka; Barja, Boris; Shimizu, Atsushi; Barbero, Albane; Salvador, Jacobo; Bali, Juan Lucas; Herrera, Milagros; Etala, Paula; Acquesta, Alejandro; Quel, Eduardo; Sugimoto, Nobuo; Mizuno, Akira

    2018-04-01

    The South American Environmental Risk Management Network (SAVER-Net) is an instrumentation network, mainly composed by lidars, to provide real-time information for atmospheric hazards and risk management purposes in South America. This lidar network have been developed since 2012 and all its sampling points are expected to be fully implemented by 2017. This paper describes the network's status and configuration, the data acquisition and processing scheme (protocols and data levels), as well as some aspects of the scientific networking in Latin American Lidar Network (LALINET). Similarly, the paper lays out future plans on the operation and integration to major international collaborative efforts.

  11. Ionospheric TEC Weather Map Over South America

    Science.gov (United States)

    Takahashi, H.; Wrasse, C. M.; Denardini, C. M.; Pádua, M. B.; de Paula, E. R.; Costa, S. M. A.; Otsuka, Y.; Shiokawa, K.; Monico, J. F. Galera; Ivo, A.; Sant'Anna, N.

    2016-11-01

    Ionospheric weather maps using the total electron content (TEC) monitored by ground-based Global Navigation Satellite Systems (GNSS) receivers over South American continent, TECMAP, have been operationally produced by Instituto Nacional de Pesquisas Espaciais's Space Weather Study and Monitoring Program (Estudo e Monitoramento Brasileiro de Clima Especial) since 2013. In order to cover the whole continent, four GNSS receiver networks, (Rede Brasileiro de Monitoramento Contínuo) RBMC/Brazilian Institute for Geography and Statistics, Low-latitude Ionospheric Sensor Network, International GNSS Service, and Red Argentina de Monitoreo Satelital Continuo, in total 140 sites, have been used. TECMAPs with a time resolution of 10 min are produced in 12 h time delay. Spatial resolution of the map is rather low, varying between 50 and 500 km depending on the density of the observation points. Large day-to-day variabilities of the equatorial ionization anomaly have been observed. Spatial gradient of TEC from the anomaly trough (total electron content unit, 1 TECU = 1016 el m-2 (TECU) 80) causes a large ionospheric range delay in the GNSS positioning system. Ionospheric plasma bubbles, their seeding and development, could be monitored. This plasma density (spatial and temporal) variability causes not only the GNSS-based positioning error but also radio wave scintillations. Monitoring of these phenomena by TEC mapping becomes an important issue for space weather concern for high-technology positioning system and telecommunication.

  12. Clusters of sirenomelia in South America.

    Science.gov (United States)

    Orioli, Iêda M; Mastroiacovo, Pierpaolo; López-Camelo, Jorge S; Saldarriaga, Wilmar; Isaza, Carolina; Aiello, Horacio; Zarante, Ignacio; Castilla, Eduardo E

    2009-02-01

    One hospital in the city of Cali, Colombia, of the ECLAMC (Latin-American Collaborative Study of Congenital Malformations) network, reported the unusual occurrence of four cases of sirenomelia within a 55-day period. An ECLAMC routine for cluster evaluation (RUMOR) was followed that included: calculations of observed/expected ratios, site visits, comparison with comprehensively collected local, South American, and worldwide data, cluster analysis, and search for risk factors. All four Cali sirenomelia cases were born to mothers living in a 2 km(2) area, in neighboring communes, within the municipality of Cali. Considering the total births of the city of Cali as the denominator, and based on ECLAMC baseline birth prevalence rates (per 100,000) for sirenomelia (2.25, 95% CI: 2.66, 3.80), the cluster for this congenital abnormality was unlikely to have occurred by chance (observed/expected ratio = 5.77; 95% CI: 1.57-14.78; p = .002). No consistent common factor was identified, but vicinity to an open landfill as the cause could not be rejected. Another ECLAMC hospital in San Justo, Buenos Aires, Argentina, reported three further cases but these did not seem to constitute a nonrandom cluster. The methodology used to evaluate the two possible clusters of sirenomelia determined that the Cali sirenomelia cluster was unlikely to have occurred by chance whereas the sirenomelia cluster from San Justo seemed to be random. . (c) 2008 Wiley-Liss, Inc.

  13. Central and South America GPS geodesy - CASA Uno

    Science.gov (United States)

    Kellogg, James N.; Dixon, Timothy H.

    1990-01-01

    In January 1988, scientists from over 25 organizations in 13 countries and territories cooperated in the largest GPS campaign in the world to date. A total of 43 GPS receivers collected approximately 590 station-days of data in American Samoa, Australia, Canada, Colombia, Costa Rica, Ecuador, New Zealand, Norway, Panama, Sweden, United States, West Germany, and Venezuela. The experiment was entitled CASA Uno. Scientific goals of the project include measurements of strain in the northern Andes, subduction rates for the Cocos and Nazca plates beneath Central and South America, and relative motion between the Caribbean plate and South America. A second set of measurements are planned in 1991 and should provide preliminary estimates of crustal deformation and plate motion rates in the region.

  14. Intravitreal Angiostrongylus cantonensis: first case report in South America

    Directory of Open Access Journals (Sweden)

    Gabriel Costa de Andrade

    Full Text Available ABSTRACT This study reports the first case of intravitreal angiostrongyliasis in South America treated with posterior worm removal via pars plana vitrectomy. This was a retrospective, observational case study. Data from medical charts, wide-field digital imaging, ocular ultrasound, and visual evoked potential studies were reviewed. A 20-month-old boy presented with eosinophilic meningitis and right eye exotropia. Polymerase chain reaction analysis of the cerebrospinal fluid showed a positive result for Angiostrongylus cantonensis. Fundus examination revealed a pale optic disc, subretinal tracks, vitreous opacities, peripheral tractional retinal detachment, and a dead worm in the vitreous cavity. The patient underwent pars plana vitrectomy with worm removal. This case report illustrates the first case of intravitreal angiostrongyliasis in South America, possibly related to the uncontrolled spread of an exotic invasive species of snail.

  15. Perspectivs and challenges of phenology research on South America

    Science.gov (United States)

    Patrícia Morellato, Leonor

    2017-04-01

    Detecting plant responses to environmental changes across the Southern Hemisphere is an important question in the global agenda, as there is still a shortage of studies addressing phenological trends related to global warming. Here I bring a fresh perspective on the current knowledge of South America's phenology, and discusss the challenges and future research agendas for one of the most diverse regions of the world. I will syntethize: (i) What is the current focus of contemporany phenological research in South America? (ii) Is phenology contributing to the detection of trends and shifts related to climate or antropogenic changes? (iii) How has phenology been integrated to conservation, restoration, and management of natural vegetation and endangered species? (iv) What would be the main challenges and new avenues for South American phenological research in the 21st century? (v) Can we move towards phenology monitoring networks, linked to citizen science and education? My perspective is based on recent reviews addressing the Southeastern Hemisphere, South America, and Neotropical phenology; and on reviews and essays on the contribution of phenological research to biodiversity conservation, management, and ecological restoration, emphasizing tropical, species-rich ecosystems. Phenological research has grown at an unprecedented rate in the last 20 years, surpassing 100 articles per year after 2010. There is still a predominance of short-term studies (2-3 years) describing patterns and drivers for reproduction and leaf exchange. Only 10 long-term studies were found, based on direct observations or plant traps, and this number did not add much to the previous surveys. Therefore, we remain in need of more long-term studies to enhance the contribution of phenology to climate change research in South America. It is also mandatory to bring conservation issues to phenology research. The effects of climatic and antropogenic changes on plant phenology have been addressed

  16. Changes in atmospheric rivers and moisture transport over the Northeast Pacific and western North America in response to ENSO diversity

    Science.gov (United States)

    Kim, Hye-Mi; Zhou, Yang; Alexander, Michael A.

    2017-03-01

    The year-to-year changes in atmospheric rivers (ARs) and moisture transport over the northeast Pacific and western North America are investigated during December to February (DJF) from 1979/80 to 2015/16. Changes in AR frequency, intensity, and landfall characteristics are compared between three ENSO phases: central Pacific El Niño (CPEN), eastern Pacific El Niño (EPEN), and La Niña (NINA). During EPEN events, the subtropical jet extends to the south and east with an anomalous cyclonic flow around a deeper Aleutian Low. More moisture is transported towards North America and AR frequency is increased over western North America. In CPEN events, the Aleutian low shifts further southward relative to its position in EPEN, resulting in an increase in the frequency and intensity of landfalling ARs over the southwestern US. In NINA events, the landfalling AR frequency is reduced associated with anomalous anticyclonic circulation over the eastern North Pacific. We diagnose the contribution of multiple factors to the seasonal mean moisture transport using moisture budgets. During the three ENSO phases, the change in low-frequency circulation (dynamical process) is the leading contributor to the seasonal mean moisture flux divergence, while the contributions of the synoptic anomalies and the change in moisture anomaly (thermodynamic process) are not significant along the west coast of North America.

  17. Evaluation of Water Resources in Bolivia, South America

    Science.gov (United States)

    1991-01-01

    liters/second demanded). Because of the effects of the drought, SEMAPA (Servicio Municipal de Agua Potables y Alcantarillado, the area water supply...departments of Potosi and Cochabamba and is in the eastern range of the Andes mountains. The western edge of the department borders Chile and is in the...Cochabamba to the east, Potosi to the south and Chile to the West. Encompassing 53,588 square kilometers, Oruro ranks fifth in size out of the seven

  18. Measures to Facilitate Necessity Entrepreneurship : Western Cape South Africa

    OpenAIRE

    Macura, Alexander; Sjölund, John

    2005-01-01

    Problem- In the townships and rural areas of the Western Cape province of South Africa unemployment can be as high as 60%. For many, starting a business is the only viable option to survive. There are many organizations seeking to help entrepreneurs to successfully start and manage a business, but services are significantly lacking. We therefore wish to determine what business service providers in the Western Cape are doing today to help necessity entrepreneurs succeed, and what can be done b...

  19. [Ritual use of Anadenanthera seeds among South America natives].

    Science.gov (United States)

    Carod-Artal, F J; Vázquez Cabrera, C B

    2007-01-01

    Several South-American native societies snuff psychoactive seeds in magic-religious rituals since ancient times. To describe archeological, historical and ethnographical evidences regarding the ritual use of vilca or yopo (Anadenanthera sp). Anadenanthera seeds were used in South America 3,000 years ago. Archeological studies found vilca seeds in funerary tombs from 1,000 BC in the north of Chile and Argentina; ceramics and snuff tubes were found in San Pedro de Atacama archeological sites from the same data, and in Tiwanaku ceremonial center in Bolivian Altiplano. Today, Anadenanthera sp is used by several native groups in Orinoco basin, where is known as yopo, and in the Brazilian and Colombian Amazon. Hallucinogenic effect is due to the presence of methyl-tryptamine derivatives. Most snuff is prepared from the roasted and powdered seeds, vegetable ash and/or lime obtained from shells. Archeological and ethnographical data suggest that vilca was used and is still used by native shamans as a sacred seed in South America, due to its hallucinogenic effects.

  20. Regional simulation of interannual variability over South America

    Science.gov (United States)

    Misra, V.; Dirmeyer, P. A.; Kirtman, B. P.; Juang, H.-M. Henry; Kanamitsu, M.

    2002-08-01

    Three regional climate simulations covering the austral summer season during three contrasting phases of the El Niño-Southern Oscillation cycle were conducted with the Regional Spectral Model (RSM) developed at the National Centers for Environmental Prediction (NCEP). The simulated interannual variability of precipitation over the Amazon River Basin, the Intertropical Convergence Zone, the Pacific and Atlantic Ocean basins, and extratropical South America compare reasonably well with observations. The RSM optimally filters the peturbations about a time-varying base field, thereby enhancing the information content of the global NCEP reanalysis. The model is better than the reanalysis in reproducing the observed interannual variability of outgoing longwave radiation at both high frequencies (3-30 days) and intraseasonal (30-60 days) scales. The low-level jet shows a peak in its speed in 1998 and a minimum in the 1999 simulations. The lag correlation of the jet index with convection over various areas in continental South America indicates that the jet induces precipitation over the Pampas region downstream. A detailed moisture budget was conducted over various subregions. This budget reveals that moisture flux convergence determines most of the interannual variability of precipitation over the Amazon Basin, the Atlantic Intertropical Convergence Zone, and the Nordeste region of Brazil. However, both surface evaporation and surface moisture flux convergence were found to be critical in determining the interannual variability of precipitation over the southern Pampas, Gran Chaco area, and the South Atlantic Convergence Zone.

  1. Seasonal influence of ENSO on the Atlantic ITCZ and equatorial South America

    Science.gov (United States)

    Münnich, M.; Neelin, J. D.

    2005-11-01

    In late boreal spring, especially May, a strong relationship exists in observations among precipitation anomalies over equatorial South America and the Atlantic intertropical convergence zone (ITCZ), and eastern equatorial Pacific and central equatorial Atlantic sea surface temperature anomalies (SSTA). A chain of correlations of equatorial Pacific SSTA, western equatorial Atlantic wind stress (WEA), equatorial Atlantic SSTA, sea surface height, and precipitation supports a causal chain in which El Niño/Southern Oscillation (ENSO) induces WEA stress anomalies, which in turn affect Atlantic equatorial ocean dynamics. These correlations show strong seasonality, apparently arising within the atmospheric links of the chain. This pathway and the influence of equatorial Atlantic SSTA on South American rainfall in May appear independent of that of the northern tropical Atlantic. Brazil's Nordeste is affected by the northern tropical Atlantic. The equatorial influence lies further to the north over the eastern Amazon and the Guiana Highlands.

  2. Peterjamesia circumscripta (Leight.) D. Hawksw. (Roccellaceae: Ascomycota): First record to continental South America

    OpenAIRE

    Gumboski, Emerson; Eliasaro, Sionara

    2012-01-01

    Peterjamesia circumscripta, previously known from Australia, Europe, North Africa, North and Central America, and Galapagos Islands was collected in southern Brazil. This is the first record of this species in continental South America.

  3. Impact of Asian Soft Power in Latin America - China and South Korea as Emerging Powers in the Subcontinent

    OpenAIRE

    Milanowitsch, Bianca Katharina; Derichs, Claudia (Prof. Dr.)

    2018-01-01

    Has the use of soft power as a strategic foreign policy tool enabled China and South Korea to position themselves as emerging powers in Latin America? This study operationalizes and conceptualizes the concept of soft power by measuring it through specific categories within a case study and offers an extended definition of emerging powers. The concept of soft power has been defined by IR theory as a tool only available to hegemonic or strong powers, which has perpetuated an inherent western bi...

  4. Dynamic Downscaling of Seasonal Simulations over South America.

    Science.gov (United States)

    Misra, Vasubandhu; Dirmeyer, Paul A.; Kirtman, Ben P.

    2003-01-01

    In this paper multiple atmospheric global circulation model (AGCM) integrations at T42 spectral truncation and prescribed sea surface temperature were used to drive regional spectral model (RSM) simulations at 80-km resolution for the austral summer season (January-February-March). Relative to the AGCM, the RSM improves the ensemble mean simulation of precipitation and the lower- and upper-level tropospheric circulation over both tropical and subtropical South America and the neighboring ocean basins. It is also seen that the RSM exacerbates the dry bias over the northern tip of South America and the Nordeste region, and perpetuates the erroneous split intertropical convergence zone (ITCZ) over both the Pacific and Atlantic Ocean basins from the AGCM. The RSM at 80-km horizontal resolution is able to reasonably resolve the Altiplano plateau. This led to an improvement in the mean precipitation over the plateau. The improved resolution orography in the RSM did not substantially change the predictability of the precipitation, surface fluxes, or upper- and lower-level winds in the vicinity of the Andes Mountains from the AGCM. In spite of identical convective and land surface parameterization schemes, the diagnostic quantities, such as precipitation and surface fluxes, show significant differences in the intramodel variability over oceans and certain parts of the Amazon River basin (ARB). However, the prognostic variables of the models exhibit relatively similar model noise structures and magnitude. This suggests that the model physics are in large part responsible for the divergence of the solutions in the two models. However, the surface temperature and fluxes from the land surface scheme of the model [Simplified Simple Biosphere scheme (SSiB)] display comparable intramodel variability, except over certain parts of ARB in the two models. This suggests a certain resilience of predictability in SSiB (over the chosen domain of study) to variations in horizontal

  5. Using Remote Sensing Products for Environmental Analysis in South America

    Directory of Open Access Journals (Sweden)

    Fabrício Brito Silva

    2011-09-01

    Full Text Available Land cover plays a major role in many biogeochemical models that represent processes and connections with terrestrial systems; hence, it is a key component for public decisions in ecosystems management. The advance of remote sensing technology, combined with the emergence of new operational products, offers alternatives to improve the accuracy of environmental monitoring and analysis. This work uses the GLOBCOVER, the Vegetation Continuous Field (VCF, MODIS Fire Radiative Power (FRP and the Tropical Rainfall Measuring Mission (TRMM remotely sensed databases to analyze the biomass burning distribution, the land use and land cover characteristics and the percent of tree cover in South America during the years 2000 to 2005. Initially, GLOBCOVER was assessed based on VCF product, and subsequently used for quantitative analysis of the spatial distribution of the South America fires with the fire radiative power (FRP. The results show that GLOBCOVER has a tendency to overestimate forest classes and to underestimate urban and mangroves areas. The fire quantification based on GLOBCOVER product shows that the highest incidence of fires can be observed in the arc of deforestation, located in the Amazon forest border, with vegetation cover composed mainly of broadleaved evergreen or semi-deciduous forest. A time series analysis of FRP database indicates that biomass burning occurs mainly in areas of broadleaved evergreen or semi-deciduous forest and in Brazilian Cerrado associated with grassland management, agricultural land clearing and with the deforestation of Amazon tropical rainforest. Also, variations in FRP intensity and spread can be attributed to rainfall anomalies, such as in 2004, when South America had a positive anomaly rainfall.

  6. Earth - South America (first frame of Earth Spin Movie)

    Science.gov (United States)

    1990-01-01

    This color image of the Earth was obtained by Galileo at about 6:10 a.m. Pacific Standard Time on Dec. 11, 1990, when the spacecraft was about 1.3 million miles from the planet during the first of two Earth flybys on its way to Jupiter. The color composite used images taken through the red, green and violet filters. South America is near the center of the picture, and the white, sunlit continent of Antarctica is below. Picturesque weather fronts are visible in the South Atlantic, lower right. This is the first frame of the Galileo Earth spin movie, a 500- frame time-lapse motion picture showing a 25-hour period of Earth's rotation and atmospheric dynamics.

  7. Quality assessment of published health economic analyses from South America.

    Science.gov (United States)

    Machado, Márcio; Iskedjian, Michael; Einarson, Thomas R

    2006-05-01

    Health economic analyses have become important to healthcare systems worldwide. No studies have previously examined South America's contribution in this area. To survey the literature with the purpose of reviewing, quantifying, and assessing the quality of published South American health economic analyses. A search of MEDLINE (1990-December 2004), EMBASE (1990-December 2004), International Pharmaceutical Abstracts (1990-December 2004), Literatura Latino-Americana e do Caribe em Ciências da Saúde (1982-December 2004), and Sistema de Informacion Esencial en Terapéutica y Salud (1980-December 2004) was completed using the key words cost-effectiveness analysis (CEA), cost-utility analysis (CUA), cost-minimization analysis (CMA), and cost-benefit analysis (CBA); abbreviations CEA, CUA, CMA, and CBA; and all South American country names. Papers were categorized by type and country by 2 independent reviewers. Quality was assessed using a 12 item checklist, characterizing scores as 4 (good), 3 (acceptable), 2 (poor), 1 (unable to judge), and 0 (unacceptable). To be included in our investigation, studies needed to have simultaneously examined costs and outcomes. We retrieved 25 articles; one duplicate article was rejected, leaving 24 (CEA = 15, CBA = 6, CMA = 3; Brazil = 9, Argentina = 5, Colombia = 3, Chile = 2, Ecuador = 2, 1 each from Peru, Uruguay, Venezuela). Variability between raters was less than 0.5 point on overall scores (OS) and less than 1 point on all individual items. Mean OS was 2.6 (SD 1.0, range 1.4-3.8). CBAs scored highest (OS 2.8, SD 0.8), CEAs next (OS 2.7, SD 0.7), and CMAs lowest (OS 2.0, SD 0.5). When scored by type of question, definition of study aim scored highest (OS 3.0, SD 0.8), while ethical issues scored lowest (OS 1.5, SD 0.9). By country, Peru scored highest (mean OS 3.8) and Uruguay had the lowest scores (mean OS 2.2). A nonsignificant time trend was noted for OS (R2 = 0.12; p = 0.104). Quality scores of health economic analyses

  8. Continent at a Crossroads: Prosperity, Justice, and Security in South America

    National Research Council Canada - National Science Library

    Scott, Frances K

    2006-01-01

    This Special Bibliography Series, Number 107, "Continent at the Crossroads: Prosperity, Justice, and Security in South America," was developed by Social Sciences Bibliographer and Reference Librarian Frances K...

  9. Cancer distribution pattern in south-western Nigeria | Awodele ...

    African Journals Online (AJOL)

    The burden of cancer in Nigeria is appreciable with about 100,000 new cancer cases been reported in the country each year. This study aimed to determine the level of occurrence and pattern of distribution of different cancer types in two major functional cancer registries in south-western Nigeria. A desk review of the level ...

  10. Reconstruction of caribou evolutionary history in Western North America and its implications for conservation.

    Science.gov (United States)

    Weckworth, Byron V; Musiani, Marco; McDevitt, Allan D; Hebblewhite, Mark; Mariani, Stefano

    2012-07-01

    The role of Beringia as a refugium and route for trans-continental exchange of fauna during glacial cycles of the past 2million years are well documented; less apparent is its contribution as a significant reservoir of genetic diversity. Using mitochondrial DNA sequences and 14 microsatellite loci, we investigate the phylogeographic history of caribou (Rangifer tarandus) in western North America. Patterns of genetic diversity reveal two distinct groups of caribou. Caribou classified as a Northern group, of Beringian origin, exhibited greater number and variability in mtDNA haplotypes compared to a Southern group originating from refugia south of glacial ice. Results indicate that subspecies R. t. granti of Alaska and R. t. groenlandicus of northern Canada do not constitute distinguishable units at mtDNA or microsatellites, belying their current status as separate subspecies. Additionally, the Northern Mountain ecotype of woodland caribou (presently R. t. caribou) has closer kinship to caribou classified as granti or groenlandicus. Comparisons of mtDNA and microsatellite data suggest that behavioural and ecological specialization is a more recently derived life history characteristic. Notably, microsatellite differentiation among Southern herds is significantly greater, most likely as a result of human-induced landscape fragmentation and genetic drift due to smaller population sizes. These results not only provide important insight into the evolutionary history of northern species such as caribou, but also are important indicators for managers evaluating conservation measures for this threatened species. © 2012 Blackwell Publishing Ltd.

  11. Working towards residential Radon survey in South America

    International Nuclear Information System (INIS)

    Zielinski, Jan M.; University of Ottawa, ON; Canoba, Analia C.; Shilnikova, Natalia S.; Veiga, Lene H. S.

    2008-01-01

    Information about residential radon levels in low and middle income countries is very sparse. In response to the World Health Organization initiative in the International Radon Project, we propose a research project that will address this knowledge gap in South America by conducting a residential radon survey. Following initial in vitro and in vivo studies of radon and studies of uranium miners exposed to radon, over twenty large case-control studies of lung cancer risk from exposure to residential radon have been completed worldwide by year 2004. Recently pooled data from these individual studies have been analyzed. These collaborative analyses of the indoor studies in Europe, North America, and China provide strong direct evidence that radon is causing a substantial number of lung cancers in the general population. To reduce radon lung cancer risk, national authorities must have methods and tools based on solid scientific evidence to develop sound public health policies. We propose to conduct a survey in ten South American countries using the distribution and analysis of passive alpha tracking detectors in houses selected at random in pre-selected cities in each participating country. We also present an approach to estimate the cost of carrying out such a survey and the radon laboratory infrastructure needed. The results of the proposed survey will allow to conduct assessment of the exposure to residential radon in the populations of South American countries and to assess the health impact of this exposure. The results of the project will also help national health authorities in developing national residential radon action levels and regulations, as well as provide public health guidance for radon awareness and mitigation. (author)

  12. Systematics, Phylogeny, and Distribution of Acer (maples) in the Cenozoic of Western North America

    OpenAIRE

    Wolfe, Jack A.; Tanai, Toshimasa

    1987-01-01

    The known fossil fruits and leaves of Acer from western North America represent 91 species and 28 sections, 12 of which are extinct and are described as new sections of Acer. Sixty-four species are described as new, 2 new combinations are proposed, and 6 species are left unnamed; 21 have been previously described. The most diverse sections of Acer in the Tertiary of western North America are the extinct Glabroidea (at least 13 species), Negundo (9 species), Macrophylla (8 species), and Erioca...

  13. Economic aspects for South America energy integration; Aspectos economicos para a integracao energetica da America do Sul

    Energy Technology Data Exchange (ETDEWEB)

    Vela, Jorge Alberto Alcala; Cardozo, Fernando Simoes [ELETROBRAS, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    Expansion of the internal market and external, production on a large scale and more dynamic economic growth would be the consequences of a regional integration in South America. However, due to the specific characteristics of South America this process did not occur. Many attempts were made through the years with the creation of institutions that tried to promote the integration of different forms of South America. This article analyses the current economic conditions in which this initiative is to achieve an energy integration, which seems feasible given the provision expresses the presidents of South American countries before a possible rationing of energy. Through analysis of the results it may be concluded that there is a growing demand for energy in all countries, which should be resolved first in order not to cut the development of South America. The main economic aspects which affect the process of integrating energy are the commercial structures of energy, the energy complementarities, the degree of development of infrastructure for interconnection, the industrial structure and conformation electric business. However, an immediate solution would be to boost bilateral integration energy projects and construction of transmission lines that interconnect the regional stations for the supply of electric energy. Moreover, as the conditions are not improved political and economic and there is no compatible models between technical institutions and legal and administrative, will not be achieved significant progress in the process of regional energy integration of South America. (author)

  14. 137Cs in the western South Pacific Ocean

    International Nuclear Information System (INIS)

    Yamada, Masatoshi; Wang Zhongliang

    2007-01-01

    The 137 Cs activities were determined for seawater samples from the East Caroline, Coral Sea, New Hebrides, South Fiji and Tasman Sea (two stations) Basins of the western South Pacific Ocean by γ spectrometry using a low background Ge detector. The 137 Cs activities ranged from 1.4 to 2.3 Bq m -3 over the depth interval 0-250 m and decreased exponentially from the subsurface to 1000 m depth. The distribution profiles of 137 Cs activity at these six western South Pacific Ocean stations did not differ from each other significantly. There was a remarkable difference for the vertical profiles of 137 Cs activity between the East Caroline Basin station in this study and the GEOSECS (Geochemical Ocean Sections Study) station at the same latitude in the Equatorial Pacific Ocean; the 137 Cs inventory over the depth interval 100-1000 m increased from 400 ± 30 Bq m -2 to 560 ± 30 Bq m -2 during the period from 1973 to 1992. The total 137 Cs inventories in the western South Pacific Ocean ranged from 850 ± 70 Bq m -2 in the Coral Sea Basin to 1270 ± 90 Bq m -2 in the South Fiji Basin. Higher 137 Cs inventories were observed at middle latitude stations in the subtropical gyre than at low latitude stations. The 137 Cs inventories were 1.9-4.5 times (2.9 ± 0.7 on average) and 1.7-4.3 times (3.1 ± 0.7 on average) higher than that of the expected deposition density of atmospheric global fallout at the same latitude and that of the estimated 137 Cs deposition density in 10 o latitude by 10 deg. longitude grid data obtained by Aoyama et al. [Aoyama M, Hirose K, Igarashi Y. Re-construction and updating our understanding on the global weapons tests 137 Cs fallout. J Environ Monit 2006;8:431-438], respectively. The possible processes for higher 137 Cs inventories in the western South Pacific Ocean than that of the expected deposition density of atmospheric global fallout may be attributable to the inter-hemisphere dispersion of the atmospheric nuclear weapons testing 137 Cs from

  15. Multistation digisonde observations of equatorial spread F in South America

    Directory of Open Access Journals (Sweden)

    B. W. Reinisch

    2004-09-01

    Full Text Available Directional ionogram and F-region drift observations were conducted at seven digisonde stations in South America during the COPEX campaign from October to December 2002. Five stations in Brazil, one in Argentina, and one in Peru, monitored the ionosphere across the continent to study the onset and development of F-region density depletions that cause equatorial spread F (ESF. New ionosonde techniques quantitatively describe the prereversal uplifting of the F layer at the magnetic equator and the eastward motion of the depletions over the stations. Three of the Brazilian stations were located along a field line with a 350-km apex over the equator to investigate the relation of the occurrence of ESF and the presence of sporadic E-layers at the two E-region intersections of the field line. No simple correlation was found.

  16. Crash and rebound of indigenous populations in lowland South America

    Science.gov (United States)

    Hamilton, Marcus J.; Walker, Robert S.; Kesler, Dylan C.

    2014-04-01

    Lowland South America has long been a battle-ground between European colonization and indigenous survival. Initial waves of European colonization brought disease epidemics, slavery, and violence that had catastrophic impacts on indigenous cultures. In this paper we focus on the demography of 238 surviving populations in Brazil. We use longitudinal censuses from all known indigenous Brazilian societies to quantify three demographic metrics: 1) effects of European contact on indigenous populations; 2) empirical estimates of minimum viable population sizes; and 3) estimates of post-contact population growth rates. We use this information to conduct population viability analysis (PVA). Our results show that all surviving populations suffered extensive mortality during, and shortly after, contact. However, most surviving populations exhibit positive growth rates within the first decade post-contact. Our findings paint a positive demographic outlook for these indigenous populations, though long-term survival remains subject to powerful externalities, including politics, economics, and the pervasive illegal exploitation of indigenous lands.

  17. Pleistocene changes in the fauna and flora of South america.

    Science.gov (United States)

    Vuilleumier, B S

    1971-08-27

    forest elements (40) now justify the conclusion that the floras and faunas of these areas were also greatly affected by Pleistocene climatic shifts. In the broad region of South America that lies within the tropics, a series of humid-arid cycles (Appendix, 6, 8-10) drastically and repeatedly altered vegetation patterns during the Quaternary. Both montane and lowland rainforests were fragmented during dry periods and were able to reexpand during humid phases. Speciation of forest elements was initiated-and sometimes completed-in isolated patches of the fragmented forest. Secondary contact, with hybridization or reunition of populations that did not become reproductively isolated, occurred in periods of reexpansion. These biological data, combined with supportive geological evidence (Appendix, 1-11), show that climatic events during the last million or so years have affected the biota of South America as much as the Pleistocene glacial changes affected the biotas of Eurasia and North America. Since most of South America lies within tropical latitudes, it is suggested here that part of the diversity of species in the tropical areas of this continent is due to two historical factors: the lack of wholesale elimination of species (compared with northern and high latitudes), and ample opportunity for speciation in successive periods of ecological isolation. The apparent paradox of the wealth of species in the "stable tropics" is partially explained by the fact that the tropics have probably been quite unstable, from the point of view of their biotas, during the Pleistocene and perhaps part of the Tertiary.

  18. Fossorial snake genus Apostolepis from South America (Serpentes: Colubridae: Elapomorphinae

    Directory of Open Access Journals (Sweden)

    De Lema, Thales

    2001-07-01

    Full Text Available An update commented list of the snake genus Apostolepis from South America, with keys for identification of the species. They are fossorial snakes that present different coloration according their distribution: (a 7 to 3 dark stripes coloration, without light nuchal collar (if present, vestigial, with snout not projected beyond jaws - in Amazonian and enclaves within Caatinga domain; (b 5 dark striped dorsal pattern, snout projected, usually without white nuchal collars — from region of contact between Cerrado and Chaco domains; (c dorsal pattern coloration uniformly red, with nucho-cervical collars, snout usually projected — in Cerrado with dispersion to Chaco and Caatinga; (d 2 or none dark stripes dorsally, venter immaculate or with black blotches, snout projecting: (e an aberrant pattern with oblique black dorsal stripes, without collars, head black and snout projecting — one species in an enclave within Caatinga, with 17 rows of scales instead of 15.

  19. The burden of oesophageal cancer in Central and South America.

    Science.gov (United States)

    Barrios, Enrique; Sierra, Monica S; Musetti, Carina; Forman, David

    2016-09-01

    Oesophageal cancer shows marked geographic variations and is one of the leading causes of cancer death worldwide. We described the burden of this malignancy in Central and South America. Regional and national level incidence data were obtained from 48 population-based cancer registries in 13 countries. Mortality data were obtained from the WHO mortality database. Incidence of oesophageal cancer by histological subtype were available from high-quality population-based cancer registries. Males had higher incidence and mortality rates than females (male-to-female ratios: 2-6:1 and 2-5:1). In 2003-2007, the highest rates were in Brazil, Uruguay, Argentina and Chile. Mortality rates followed the incidence patterns. Incidence of oesophageal squamous cell carcinoma (SCC) was higher than adenocarcinoma (AC), except in females from Cuenca (Ecuador). SCC and AC incidence were higher in males than females, except in the Region of Antofagasta and Valdivia (Chile), Manizales (Colombia) and Cuenca (Ecuador). Incidence and mortality rates tended to decline in Argentina, Chile, Brazil (incidence) and Costa Rica from 1997 to 2008. The geographic variation and sex disparity in oesophageal cancer across Central and South America may reflect differences in the prevalence of tobacco smoking and alcohol consumption which highlights the need to implement and/or strengthen tobacco and alcohol control policies. Maté consumption, obesity, diet and Helicobacter pylori infection may also explain the variation in oesophageal cancer rates but these relationships should be evaluated. Continuous monitoring of oesophageal cancer rates is necessary to provide the basis for cancer prevention and control in the region. Copyright © 2015 International Agency for Research on Cancer. Published by Elsevier Ltd.. All rights reserved.

  20. Growing Brazilian demand to spur gas network in South America

    International Nuclear Information System (INIS)

    Deffarges, E.H.; Maurer, L.I.A.

    1993-01-01

    A recent combination in South America of economic and geopolitical factors is prompting development of a new integrated gas-pipeline network in the continent's Southern Cone. The crucial factors include privatization, regional integration, economic growth, and environmental concerns. The area, Latin America's largest regional entity, includes Brazil (population 150 million and a 1990 GNP of about $375 billion, 9th largest in the world), Argentina (population 32 million and the third largest Latin American economy after Brazil and Mexico), Bolivia, Chile, Paraguay, and Uruguay. Argentina, Brazil, Paraguay, and Uruguay are members of the MercoSur economic bloc whose objective is to develop free trade in the region. There are very few integrated pipeline networks in the world. Besides the giant North American system, with hundreds of producers and pipelines, there is only one other large integrated network. It connects continental European countries to their outside suppliers such as Norway, the C.I.S., and Algeria. The emergence of a new pipeline system is therefore important for the natural-gas industry worldwide and even more so if it occurs in a region now growing rapidly after a decade of economic difficulties

  1. The Current State of European Studies in North America and of Scholarly Publishing in Western Europe.

    Science.gov (United States)

    Hacken, Richard

    1998-01-01

    Relates how scholarly publishing in Western Europe feeds into North America. Discusses globalization, regionalism, and particularism; new models and research methodology; Biblio-Darwinism (survival of the fittest publishing languages) and the language of the imprint; differing academic infrastructures of Europe; booming scholarly-title production;…

  2. Effects of livestock grazing on neotropical migratory landbirds in western North America

    Science.gov (United States)

    Carl E. Bock; Victoria A. Saab; Terrell D. Rich; David S. Dobkin

    1993-01-01

    Livestock grazing is a widespread and important influence on neotropical migratory birds in four major ecosystems in western North America: grasslands of the Great Plains and Southwest, riparian woodlands, Intermountain shrubsteppe, and open coniferous forests. We have reviewed available literature on avian responses to grazing in these habitats. Among 35 plains...

  3. New species of Braggia (Hemiptera: Aphididae) on buckwheat in western North America

    Science.gov (United States)

    K. S. Pike; G. Graf; R. G. Foottit; H. E. L. Maw; P. Stary; R. Hammon; D. G. Miller

    2009-01-01

    Species of Braggia Gillette and Palmer (Hemiptera: Aphididae: Aphidinae: Aphidini) feed on various buckwheat, Eriogonum Michx. (Polygonaceae), species in western North America. Two new species, Braggia columbiana Pike n. sp. from Washington and Oregon and Braggia longicauda Pike n. sp. from Washington, Oregon, and northern California, are proposed. Descriptions,...

  4. Ecology and management of morels harvested from the forests of western North America.

    Science.gov (United States)

    David Pilz; Rebecca McLain; Susan Alexander; Luis Villarreal-Ruiz; Shannon Berch; Tricia L. Wurtz; Catherine G. Parks; Erika McFarlane; Blaze Baker; Randy Molina; Jane E. Smith

    2007-01-01

    Morels are prized edible mushrooms that fruit, sometimes prolifically, in many forest types throughout western North America. They are collected for personal consumption and commercially harvested as valuable special (nontimber) forest products. Large gaps remain, however, in our knowledge about their taxonomy, biology, ecology, cultivation, safety, and how to manage...

  5. Threats to riparian ecosystems in western North America: An analysis of existing literature

    Science.gov (United States)

    Boris Poff; Karen A. Koestner; Dan Neary; Victoria Henderson

    2011-01-01

    A total of 453 journal articles, reports, books, and book chapters addressing threats to riparian ecosystems in western North America were analyzed to identify, quantify, and qualify the major threats to these ecosystems as represented in the existing literature. Publications were identified either as research, policy, literature review, historical comparison, or...

  6. Global warming and stress complexes in forests of western North America

    Science.gov (United States)

    Donald McKenzie; David L. Peterson; Jeremy J. Littell

    2009-01-01

    A warmer climate in western North America will likely affect forests directly through soil moisture stress and indirectly through increased extent and severity of disturbances. We propose that stress complexes, combinations of biotic and abiotic stresses, compromise the vigor and ultimate sustainability of forest ecosystems. Across...

  7. Quinoa cultivation in western North America: lessons learned and the path forward

    Science.gov (United States)

    Quinoa (Chenopodium quinoa Willd) is a relatively new crop to farmers in North America; however recent interest in domestic cultivation of quinoa has skyrocketed due to a rapid, worldwide increase in demand for this nutritious and delicious Andean crop. Researchers at five western U.S. universities ...

  8. Explaining ecological clusters of maternal depression in South Western Sydney.

    Science.gov (United States)

    Eastwood ED, John; Kemp, Lynn; Jalaludin, Bin

    2014-01-24

    The aim of the qualitative study reported here was to: 1) explain the observed clustering of postnatal depressive symptoms in South Western Sydney; and 2) identify group-level mechanisms that would add to our understanding of the social determinants of maternal depression. Critical realism provided the methodological underpinning for the study. The setting was four local government areas in South Western Sydney, Australia. Child and Family practitioners and mothers in naturally occurring mothers groups were interviewed. Using an open coding approach to maximise emergence of patterns and relationships we have identified seven theoretical concepts that might explain the observed spatial clustering of maternal depression. The theoretical concepts identified were: Community-level social networks; Social Capital and Social Cohesion; "Depressed community"; Access to services at the group level; Ethnic segregation and diversity; Supportive social policy; and Big business. We postulate that these regional structural, economic, social and cultural mechanisms partially explain the pattern of maternal depression observed in families and communities within South Western Sydney. We further observe that powerful global economic and political forces are having an impact on the local situation. The challenge for policy and practice is to support mothers and their families within this adverse regional and global-economic context.

  9. Explaining ecological clusters of maternal depression in South Western Sydney

    Science.gov (United States)

    2014-01-01

    Background The aim of the qualitative study reported here was to: 1) explain the observed clustering of postnatal depressive symptoms in South Western Sydney; and 2) identify group-level mechanisms that would add to our understanding of the social determinants of maternal depression. Methods Critical realism provided the methodological underpinning for the study. The setting was four local government areas in South Western Sydney, Australia. Child and Family practitioners and mothers in naturally occurring mothers groups were interviewed. Results Using an open coding approach to maximise emergence of patterns and relationships we have identified seven theoretical concepts that might explain the observed spatial clustering of maternal depression. The theoretical concepts identified were: Community-level social networks; Social Capital and Social Cohesion; "Depressed community"; Access to services at the group level; Ethnic segregation and diversity; Supportive social policy; and Big business. Conclusions We postulate that these regional structural, economic, social and cultural mechanisms partially explain the pattern of maternal depression observed in families and communities within South Western Sydney. We further observe that powerful global economic and political forces are having an impact on the local situation. The challenge for policy and practice is to support mothers and their families within this adverse regional and global-economic context. PMID:24460690

  10. Notes from the field: chikungunya virus spreads in the Americas - Caribbean and South America, 2013-2014.

    Science.gov (United States)

    Fischer, Marc; Staples, J Erin

    2014-06-06

    In December 2013, the World Health Organization reported the first local transmission of chikungunya virus in the Western Hemisphere, with autochthonous cases identified in Saint Martin. Since then, local transmission has been identified in 17 countries or territories in the Caribbean or South America (Anguilla, Antigua and Barbuda, British Virgin Islands, Dominica, Dominican Republic, French Guiana, Guadeloupe, Guyana, Haiti, Martinique, Puerto Rico, Saint Barthelemy, Saint Kitts and Nevis, Saint Lucia, Saint Martin, Saint Vincent and the Grenadines, and Sint Maarten). As of May 30, 2014, a total of 103,018 suspected and 4,406 laboratory-confirmed chikungunya cases had been reported from these areas. The number of reported cases nearly doubled during the previous 2 weeks. More than 95% of the cases have been reported from five jurisdictions: Dominican Republic (38,656 cases), Martinique (30,715), Guadeloupe (24,428), Haiti (6,318), and Saint Martin (4,113). The highest incidences have been reported from Saint Martin (115 cases per 1,000 population), Martinique (76 per 1,000), Saint Barthelemy (74 per 1,000), and Guadeloupe (52 per 1,000). Further expansion of these outbreaks and spread to other countries in the region is likely.

  11. Field Evaluations of Topical Arthropod Repellents in North, Central, and South America

    Science.gov (United States)

    2014-09-01

    De La Rocque et al. 2011) and their spread into higher elevations of Africa, Latin America , and Asia (Epstein 2001). Dengue fever and...denguehemorrhagic fever have resurgeddramatically in Latin America (Zell 2004). In North America ,West Nile virus has impacted signiÞcantly the health and welfare of...VECTOR CONTROL, PEST MANAGEMENT, RESISTANCE, REPELLENTS Field Evaluations of Topical Arthropod Repellents in North, Central , and South America KENDRA

  12. Palm harvest impacts in north-western South America

    DEFF Research Database (Denmark)

    Balslev, Henrik

    2011-01-01

    Tropical forests harbor thousands of useful plants that are harvested and used in subsistence economies or traded in local, regional or international markets. The effect on the ecosystem is little known, and the forests resilience is badly understood. Palms are the most useful group of plants in ...

  13. Predicting grizzly bear density in western North America.

    Science.gov (United States)

    Mowat, Garth; Heard, Douglas C; Schwarz, Carl J

    2013-01-01

    Conservation of grizzly bears (Ursus arctos) is often controversial and the disagreement often is focused on the estimates of density used to calculate allowable kill. Many recent estimates of grizzly bear density are now available but field-based estimates will never be available for more than a small portion of hunted populations. Current methods of predicting density in areas of management interest are subjective and untested. Objective methods have been proposed, but these statistical models are so dependent on results from individual study areas that the models do not generalize well. We built regression models to relate grizzly bear density to ultimate measures of ecosystem productivity and mortality for interior and coastal ecosystems in North America. We used 90 measures of grizzly bear density in interior ecosystems, of which 14 were currently known to be unoccupied by grizzly bears. In coastal areas, we used 17 measures of density including 2 unoccupied areas. Our best model for coastal areas included a negative relationship with tree cover and positive relationships with the proportion of salmon in the diet and topographic ruggedness, which was correlated with precipitation. Our best interior model included 3 variables that indexed terrestrial productivity, 1 describing vegetation cover, 2 indices of human use of the landscape and, an index of topographic ruggedness. We used our models to predict current population sizes across Canada and present these as alternatives to current population estimates. Our models predict fewer grizzly bears in British Columbia but more bears in Canada than in the latest status review. These predictions can be used to assess population status, set limits for total human-caused mortality, and for conservation planning, but because our predictions are static, they cannot be used to assess population trend.

  14. Predicting grizzly bear density in western North America.

    Directory of Open Access Journals (Sweden)

    Garth Mowat

    Full Text Available Conservation of grizzly bears (Ursus arctos is often controversial and the disagreement often is focused on the estimates of density used to calculate allowable kill. Many recent estimates of grizzly bear density are now available but field-based estimates will never be available for more than a small portion of hunted populations. Current methods of predicting density in areas of management interest are subjective and untested. Objective methods have been proposed, but these statistical models are so dependent on results from individual study areas that the models do not generalize well. We built regression models to relate grizzly bear density to ultimate measures of ecosystem productivity and mortality for interior and coastal ecosystems in North America. We used 90 measures of grizzly bear density in interior ecosystems, of which 14 were currently known to be unoccupied by grizzly bears. In coastal areas, we used 17 measures of density including 2 unoccupied areas. Our best model for coastal areas included a negative relationship with tree cover and positive relationships with the proportion of salmon in the diet and topographic ruggedness, which was correlated with precipitation. Our best interior model included 3 variables that indexed terrestrial productivity, 1 describing vegetation cover, 2 indices of human use of the landscape and, an index of topographic ruggedness. We used our models to predict current population sizes across Canada and present these as alternatives to current population estimates. Our models predict fewer grizzly bears in British Columbia but more bears in Canada than in the latest status review. These predictions can be used to assess population status, set limits for total human-caused mortality, and for conservation planning, but because our predictions are static, they cannot be used to assess population trend.

  15. Performance of salmon fishery portfolios across western North America.

    Science.gov (United States)

    Griffiths, Jennifer R; Schindler, Daniel E; Armstrong, Jonathan B; Scheuerell, Mark D; Whited, Diane C; Clark, Robert A; Hilborn, Ray; Holt, Carrie A; Lindley, Steven T; Stanford, Jack A; Volk, Eric C

    2014-12-01

    Quantifying the variability in the delivery of ecosystem services across the landscape can be used to set appropriate management targets, evaluate resilience and target conservation efforts. Ecosystem functions and services may exhibit portfolio-type dynamics, whereby diversity within lower levels promotes stability at more aggregated levels. Portfolio theory provides a framework to characterize the relative performance among ecosystems and the processes that drive differences in performance. We assessed Pacific salmon Oncorhynchus spp. portfolio performance across their native latitudinal range focusing on the reliability of salmon returns as a metric with which to assess the function of salmon ecosystems and their services to humans. We used the Sharpe ratio (e.g. the size of the total salmon return to the portfolio relative to its variability (risk)) to evaluate the performance of Chinook and sockeye salmon portfolios across the west coast of North America. We evaluated the effects on portfolio performance from the variance of and covariance among salmon returns within each portfolio, and the association between portfolio performance and watershed attributes. We found a positive latitudinal trend in the risk-adjusted performance of Chinook and sockeye salmon portfolios that also correlated negatively with anthropogenic impact on watersheds (e.g. dams and land-use change). High-latitude Chinook salmon portfolios were on average 2·5 times more reliable, and their portfolio risk was mainly due to low variance in the individual assets. Sockeye salmon portfolios were also more reliable at higher latitudes, but sources of risk varied among the highest performing portfolios. Synthesis and applications . Portfolio theory provides a straightforward method for characterizing the resilience of salmon ecosystems and their services. Natural variability in portfolio performance among undeveloped watersheds provides a benchmark for restoration efforts. Locally and regionally

  16. Performance of salmon fishery portfolios across western North America

    Science.gov (United States)

    Griffiths, Jennifer R; Schindler, Daniel E; Armstrong, Jonathan B; Scheuerell, Mark D; Whited, Diane C; Clark, Robert A; Hilborn, Ray; Holt, Carrie A; Lindley, Steven T; Stanford, Jack A; Volk, Eric C

    2014-01-01

    Quantifying the variability in the delivery of ecosystem services across the landscape can be used to set appropriate management targets, evaluate resilience and target conservation efforts. Ecosystem functions and services may exhibit portfolio-type dynamics, whereby diversity within lower levels promotes stability at more aggregated levels. Portfolio theory provides a framework to characterize the relative performance among ecosystems and the processes that drive differences in performance. We assessed Pacific salmon Oncorhynchus spp. portfolio performance across their native latitudinal range focusing on the reliability of salmon returns as a metric with which to assess the function of salmon ecosystems and their services to humans. We used the Sharpe ratio (e.g. the size of the total salmon return to the portfolio relative to its variability (risk)) to evaluate the performance of Chinook and sockeye salmon portfolios across the west coast of North America. We evaluated the effects on portfolio performance from the variance of and covariance among salmon returns within each portfolio, and the association between portfolio performance and watershed attributes. We found a positive latitudinal trend in the risk-adjusted performance of Chinook and sockeye salmon portfolios that also correlated negatively with anthropogenic impact on watersheds (e.g. dams and land-use change). High-latitude Chinook salmon portfolios were on average 2·5 times more reliable, and their portfolio risk was mainly due to low variance in the individual assets. Sockeye salmon portfolios were also more reliable at higher latitudes, but sources of risk varied among the highest performing portfolios. Synthesis and applications. Portfolio theory provides a straightforward method for characterizing the resilience of salmon ecosystems and their services. Natural variability in portfolio performance among undeveloped watersheds provides a benchmark for restoration efforts. Locally and regionally

  17. Cottonwood Tree Rings and Climate in Western North America

    Science.gov (United States)

    Friedman, J. M.; Edmondson, J.; Griffin, E. R.; Meko, D. M.; Merigliano, M. F.; Scott, J. A.; Scott, M. L.; Touchan, R.

    2012-12-01

    In dry landscapes of interior western USA, cottonwood (Populus spp.) seedling establishment often occurs only close to river channels after floods. Where winter is sufficiently cold, cottonwoods also have distinct annual rings and can live up to 370 years, allowing us to reconstruct the long-term history of river flows and channel locations. We have analyzed the annual rate of cottonwood establishment along streams in Montana, Wyoming, Colorado, North Dakota and Idaho. Because the trees germinate next to the river, establishment rates are strongly correlated with the rate of channel migration driven by floods. Along large rivers dominated by snowmelt from the mountains, interannual variation in peak flows and cottonwood establishment is small, and century-scale variation driven by climate change is apparent. The upper Snake, Yellowstone and Green rivers all show a strong decrease in cottonwood establishment beginning in the late 1800s and continuing to the present, indicating a decrease in peak flows prior to flow regulation by large dams. This is consistent with published tree-ring studies of montane conifers showing decreases in snowpack at the same time scale. In contrast, beginning in the late 1800s cottonwood ring widths along the Little Missouri River, North Dakota show an increase in annual growth that continues into the present. Because annual growth is strongly correlated with April-July flows (r=0.69) the ring-width data suggest an increase in April-July flows at the same time tree establishment dates suggest a decrease in peak flows. These results may be reconciled by the hypothesis that increases in low temperatures have decreased snowpack while lengthening the growing season.

  18. A synthesis of ENSO effects on drylands in Australia, North America and South America

    Directory of Open Access Journals (Sweden)

    M. Holmgren

    2006-01-01

    Full Text Available Fundamentally, El Niño Southern Oscillation (ENSO is a climatic and oceanographic phenomenon, but it has profound effects on terrestrial ecosystems. Although the ecological effects of ENSO are becoming increasingly known from a wide range of terrestrial ecosystems (Holmgren et al., 2001, their impacts have been more intensively studied in arid and semiarid systems. In this brief communication, we summarize the main conclusions of a recent symposium on the effects of ENSO in these ecosystems, which was convened as part of the First Alexander von Humboldt International Conference on the El Niño Phenomenon and its Global Impact, in Guayaquil, Ecuador, from 16–20 May 2005. Participants in the symposium shared results and perspectives from research conducted in North and South America and Australia, regions where the ecological effects of ENSO have been studied in depth. Although the reports covered a wide array of organisms and ecological systems (Fig. 1, a recurring theme was the strong increase in rainfall associated with ENSO events in dry ecosystems (during the El Niño phase of the oscillation in the Americas and the La Niña phase in Australia. Because inter-annual variability in precipitation is such a strong determinant of productivity in arid and semiarid ecosystems, increased ENSO rainfall is crucial for plant recruitment, productivity and diversity in these ecosystems. Several long-term studies show that this pulse in primary productivity causes a subsequent increase in herbivores, followed by an increase in carnivores, with consequences for changes in ecosystem structure and functioning that can be quite complex.

  19. Improving precipitation simulation from updated surface characteristics in South America

    Science.gov (United States)

    Pereira, Gabriel; Silva, Maria Elisa Siqueira; Moraes, Elisabete Caria; Chiquetto, Júlio Barboza; da Silva Cardozo, Francielle

    2017-07-01

    Land use and land cover maps and their physical-chemical and biological properties are important variables in the numerical modeling of Earth systems. In this context, the main objective of this study is to analyze the improvements resulting from the land use and land cover map update in numerical simulations performed using the Regional Climate Model system version 4 (RegCM4), as well as the seasonal variations of physical parameters used by the Biosphere Atmosphere Transfer Scheme (BATS). In general, the update of the South America 2007 land use and land cover map, used by the BATS, improved the simulation of precipitation by 10 %, increasing the mean temporal correlation coefficient, compared to observed data, from 0.84 to 0.92 (significant at p Atlantic convergence zone (SACZ) positioning, presenting a spatial pattern of alternated areas with higher and lower precipitation rates. These important differences occur due to the replacement of tropical rainforest for pasture and agriculture and the replacement of agricultural areas for pasture, scrubland, and deciduous forest.

  20. Lowland tapir distribution and habitat loss in South America

    Directory of Open Access Journals (Sweden)

    Jose Luis Passos Cordeiro

    2016-09-01

    Full Text Available The development of species distribution models (SDMs can help conservation efforts by generating potential distributions and identifying areas of high environmental suitability for protection. Our study presents a distribution and habitat map for lowland tapir in South America. We also describe the potential habitat suitability of various geographical regions and habitat loss, inside and outside of protected areas network. Two different SDM approaches, MAXENT and ENFA, produced relative different Habitat Suitability Maps for the lowland tapir. While MAXENT was efficient at identifying areas as suitable or unsuitable, it was less efficient (when compared to the results by ENFA at identifying the gradient of habitat suitability. MAXENT is a more multifaceted technique that establishes more complex relationships between dependent and independent variables. Our results demonstrate that for at least one species, the lowland tapir, the use of a simple consensual approach (average of ENFA and MAXENT models outputs better reflected its current distribution patterns. The Brazilian ecoregions have the highest habitat loss for the tapir. Cerrado and Atlantic Forest account for nearly half (48.19% of the total area lost. The Amazon region contains the largest area under protection, and the most extensive remaining habitat for the tapir, but also showed high levels of habitat loss outside protected areas, which increases the importance of support for proper management.

  1. Lowland tapir distribution and habitat loss in South America.

    Science.gov (United States)

    Cordeiro, Jose Luis Passos; Fragoso, José M V; Crawshaw, Danielle; Oliveira, Luiz Flamarion B

    2016-01-01

    The development of species distribution models (SDMs) can help conservation efforts by generating potential distributions and identifying areas of high environmental suitability for protection. Our study presents a distribution and habitat map for lowland tapir in South America. We also describe the potential habitat suitability of various geographical regions and habitat loss, inside and outside of protected areas network. Two different SDM approaches, MAXENT and ENFA, produced relative different Habitat Suitability Maps for the lowland tapir. While MAXENT was efficient at identifying areas as suitable or unsuitable, it was less efficient (when compared to the results by ENFA) at identifying the gradient of habitat suitability. MAXENT is a more multifaceted technique that establishes more complex relationships between dependent and independent variables. Our results demonstrate that for at least one species, the lowland tapir, the use of a simple consensual approach (average of ENFA and MAXENT models outputs) better reflected its current distribution patterns. The Brazilian ecoregions have the highest habitat loss for the tapir. Cerrado and Atlantic Forest account for nearly half (48.19%) of the total area lost. The Amazon region contains the largest area under protection, and the most extensive remaining habitat for the tapir, but also showed high levels of habitat loss outside protected areas, which increases the importance of support for proper management.

  2. Mining and development: are they compatible in South America

    Energy Technology Data Exchange (ETDEWEB)

    Page, W

    1976-12-01

    Mining operations will require new methods and policies if they are to be of positive benefit to Third World countries. A review of experiences in South America reveals that few jobs were created in spite of intensive capital costs. Concentration of political power in a small elite group, such as miners, tends to counter efforts to improve working conditions and bring about better income distribution to the general population. Foreign exchange earnings and central government revenues benefit disproportionately to the social and economic needs of the people. More appropriate policies for developing countries will (1) seek mining opportunities with lower capital and higher labor intensity, (2) reduce foreign mining expenditures in favor of local input, and (3) reassess the government and mining-sector relationship as it applies to investment of mining surpluses. Any new policy directions will have to cope with the reluctance of miners to accept changes that are not in their direct interest and with those incompatible with tribal ancestral land use. Countries with a large investment in mining operations will be reluctant to change policies, particularly those recommended by outsiders. (24 references) (DCK)

  3. The first hypothelminorheic Crustacea (Amphipoda, Dogielinotidae, Hyalella from South America

    Directory of Open Access Journals (Sweden)

    Stella Rodrigues

    2012-11-01

    Full Text Available Most of known troglobiotic species occur in caves and subterranean environments from great depths. However, recently more attention has been given to other subterranean environments, such as the hypothelminorheic habitats. It comprises the most superficial among all subterranean habitats. This kind of environment is characterized by the constant presence of wet spots, absence of light and very particular abiotic characteristics, comprising unique species. The first hypothelminorheic Amphipoda from South America is here described, a new species of the genus Hyalella which occurs in a wetland on Southern Brazil. The new species differs from other troglobiotics of the genus by the presence of a curved seta on the inner ramus of uropod 1 and elongation of appendices, as the first pair of antennae and peraeopods 6 and 7. However, human impacts in the area where the new species occurs have changed heavily their habitat, which may have led the species to a critical level of threat or even extinction, demonstrating the fragility of this environment.a

  4. Opportunities and challenges in developing gas markets in South America

    Energy Technology Data Exchange (ETDEWEB)

    Duarte, Cristiano Boaventura [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The article has the objective of identifying and analyzing the key market levers and drivers, emerging issues and challenges in developing the gas markets in South America. In section 1, the paper provides an overview of the most relevant indicators in the natural gas markets of the region. Data such as natural gas proven reserves; production; consumption; trade movements (by pipeline and LNG) and main aspects of regulatory framework are shown. In section 2, some of the key challenges and opportunities in developing gas markets in the region are identified, including those relating to market integration, political aspects and the main players' investments. In section 3, possible strategies from governments and enterprises to overcome those challenges, and seize the potential opportunities of the region are examined. In section 4, the conclusions point to the potential of developing the gas markets as a means to diversify the energy sources in the region, fostering a successful process of economic growth and political integration in the area. (author)

  5. Cystic echinococcosis in South America: a call for action

    Directory of Open Access Journals (Sweden)

    Carlos F. Pavletic

    2017-08-01

    Full Text Available ABSTRACT Cystic echinococcosis (CE or hydatidosis, a parasitic zoonosis caused by a cestode of the family Taeniidae, species Echinococcus granulosus, is endemic in Argentina, Chile, Peru, Uruguay, and southern Brazil. This report presents CE figures for these five countries in 2009 – 2014 and proposes indicators to measure national control programs. Nearly 5 000 new CE cases were diagnosed annually in the five countries during the study period. The average case fatality rate was 2.9%, which suggests that CE led to approximately 880 deaths in these countries during the 6-year period. CE cases that required secondary or tertiary health care had average hospital stays of 10.6 days, causing a significant burden to health systems. The proportion of new cases (15% in children less than 15 years of age suggests ongoing transmission. Despite figures showing that CE is not under control in South America, the long-standing implementation of national and local control programs in three of the five countries has achieved reductions in some of the indicators. The Regional Initiative for the Control of CE, which includes the five countries and provides a framework for networking and collaboration, must intensify its efforts.

  6. Robotic-assisted partial Nephrectomy: initial experience in South America

    Directory of Open Access Journals (Sweden)

    Gustavo C. Lemos

    2011-08-01

    Full Text Available OBJECTIVE:To report the initial outcomes of robotic-assisted partial nephrectomy in a tertiary center in South America. MATERIAL AND METHODS: From 11/2008 to 12/2009, a total of 16 transperitoneal robotic-assisted partial nephrectomies were performed in 15 patients to treat 18 kidney tumors. One patient with bilateral tumor had two procedures, while two patients with two synchronous unilateral tumors had a single operation to remove them. Eleven (73% patients were male and the right kidney was affected in 7 (46% patients. The median patient age and tumor size were 57 years old and 30 mm, respectively. Five (28% tumors were hilar and/or centrally located. RESULTS: The median operative time, warm ischemia time and estimated blood loss was 140 min, 27 min and 120 mL, respectively. Blood transfusion was required in one patient with bilateral tumor, and one additional pyelolithotomy was performed due to a 15mm stone located in the renal pelvis. The histopathology analysis showed 15 (83% malignant tumors, which 10 (67% were clear cell carcinoma. The median hospital stay was 72 hrs and no major complication was observed. CONCLUSION: Robotic-assisted partial nephrectomy is safe and represents a valuable option to perform minimally invasive nephron-sparing surgery.

  7. Distributed ice thickness and glacier volume in southern South America

    Science.gov (United States)

    Carrivick, Jonathan L.; Davies, Bethan J.; James, William H. M.; Quincey, Duncan J.; Glasser, Neil F.

    2016-11-01

    South American glaciers, including those in Patagonia, presently contribute the largest amount of meltwater to sea level rise per unit glacier area in the world. Yet understanding of the mechanisms behind the associated glacier mass balance changes remains unquantified partly because models are hindered by a lack of knowledge of subglacial topography. This study applied a perfect-plasticity model along glacier centre-lines to derive a first-order estimate of ice thickness and then interpolated these thickness estimates across glacier areas. This produced the first complete coverage of distributed ice thickness, bed topography and volume for 617 glaciers between 41°S and 55°S and in 24 major glacier regions. Maximum modelled ice thicknesses reach 1631 m ± 179 m in the South Patagonian Icefield (SPI), 1315 m ± 145 m in the North Patagonian Icefield (NPI) and 936 m ± 103 m in Cordillera Darwin. The total modelled volume of ice is 1234.6 km3 ± 246.8 km3 for the NPI, 4326.6 km3 ± 865.2 km3 for the SPI and 151.9 km3 ± 30.38 km3 for Cordillera Darwin. The total volume was modelled to be 5955 km3 ± 1191 km3, which equates to 5458.3 Gt ± 1091.6 Gt ice and to 15.08 mm ± 3.01 mm sea level equivalent (SLE). However, a total area of 655 km2 contains ice below sea level and there are 282 individual overdeepenings with a mean depth of 38 m and a total volume if filled with water to the brim of 102 km3. Adjusting the potential SLE for the ice volume below sea level and for the maximum potential storage of meltwater in these overdeepenings produces a maximum potential sea level rise (SLR) of 14.71 mm ± 2.94 mm. We provide a calculation of the present ice volume per major river catchment and we discuss likely changes to southern South America glaciers in the future. The ice thickness and subglacial topography modelled by this study will facilitate future studies of ice dynamics and glacier isostatic adjustment, and will be important for projecting water resources and

  8. First Detection of Bat White-Nose Syndrome in Western North America.

    Science.gov (United States)

    Lorch, Jeffrey M; Palmer, Jonathan M; Lindner, Daniel L; Ballmann, Anne E; George, Kyle G; Griffin, Kathryn; Knowles, Susan; Huckabee, John R; Haman, Katherine H; Anderson, Christopher D; Becker, Penny A; Buchanan, Joseph B; Foster, Jeffrey T; Blehert, David S

    2016-01-01

    White-nose syndrome (WNS) is an emerging fungal disease of bats caused by Pseudogymnoascus destructans. Since it was first detected near Albany, NY, in 2006, the fungus has spread across eastern North America, killing unprecedented numbers of hibernating bats. The devastating impacts of WNS on Nearctic bat species are attributed to the likely introduction of P. destructans from Eurasia to naive host populations in eastern North America. Since 2006, the disease has spread in a gradual wavelike pattern consistent with introduction of the pathogen at a single location. Here, we describe the first detection of P. destructans in western North America in a little brown bat (Myotis lucifugus) from near Seattle, WA, far from the previously recognized geographic distribution of the fungus. Whole-genome sequencing and phylogenetic analyses indicated that the isolate of P. destructans from Washington grouped with other isolates of a presumed clonal lineage from the eastern United States. Thus, the occurrence of P. destructans in Washington does not likely represent a novel introduction of the fungus from Eurasia, and the lack of intensive surveillance in the western United States makes it difficult to interpret whether the occurrence of P. destructans in the Pacific Northwest is disjunct from that in eastern North America. Although there is uncertainty surrounding the impacts of WNS in the Pacific Northwest, the presence of the pathogen in western North America could have major consequences for bat conservation. IMPORTANCE White-nose syndrome (WNS) represents one of the most consequential wildlife diseases of modern times. Since it was first documented in New York in 2006, the disease has killed millions of bats and threatens several formerly abundant species with extirpation or extinction. The spread of WNS in eastern North America has been relatively gradual, inducing optimism that disease mitigation strategies could be established in time to conserve bats susceptible

  9. First detection of bat white-nose syndrome in western North America

    Science.gov (United States)

    Lorch, Jeffrey M.; Palmer, Jonathan M.; Lindner, Daniel L.; Ballmann, Anne; George, Kyle; Griffin, Kathryn M.; Knowles, Susan N.; Huckabee, John R.; Haman, Katherine H.; Anderson, Christopher D.; Becker, Penny A.; Buchanan, Joseph B.; Foster, Jeffrey T.; Blehert, David

    2016-01-01

    White-nose syndrome (WNS) is an emerging fungal disease of bats caused by Pseudogymnoascus destructans. Since it was first detected near Albany, NY, in 2006, the fungus has spread across eastern North America, killing unprecedented numbers of hibernating bats. The devastating impacts of WNS on Nearctic bat species are attributed to the likely introduction of P. destructans from Eurasia to naive host populations in eastern North America. Since 2006, the disease has spread in a gradual wavelike pattern consistent with introduction of the pathogen at a single location. Here, we describe the first detection of P. destructans in western North America in a little brown bat (Myotis lucifugus) from near Seattle, WA, far from the previously recognized geographic distribution of the fungus. Whole-genome sequencing and phylogenetic analyses indicated that the isolate of P. destructans from Washington grouped with other isolates of a presumed clonal lineage from the eastern United States. Thus, the occurrence of P. destructans in Washington does not likely represent a novel introduction of the fungus from Eurasia, and the lack of intensive surveillance in the western United States makes it difficult to interpret whether the occurrence of P. destructans in the Pacific Northwest is disjunct from that in eastern North America. Although there is uncertainty surrounding the impacts of WNS in the Pacific Northwest, the presence of the pathogen in western North America could have major consequences for bat conservation.

  10. Simulated bat populations erode when exposed to climate change projections for western North America.

    Directory of Open Access Journals (Sweden)

    Mark A Hayes

    Full Text Available Recent research has demonstrated that temperature and precipitation conditions correlate with successful reproduction in some insectivorous bat species that live in arid and semiarid regions, and that hot and dry conditions correlate with reduced lactation and reproductive output by females of some species. However, the potential long-term impacts of climate-induced reproductive declines on bat populations in western North America are not well understood. We combined results from long-term field monitoring and experiments in our study area with information on vital rates to develop stochastic age-structured population dynamics models and analyzed how simulated fringed myotis (Myotis thysanodes populations changed under projected future climate conditions in our study area near Boulder, Colorado (Boulder Models and throughout western North America (General Models. Each simulation consisted of an initial population of 2,000 females and an approximately stable age distribution at the beginning of the simulation. We allowed each population to be influenced by the mean annual temperature and annual precipitation for our study area and a generalized range-wide model projected through year 2086, for each of four carbon emission scenarios (representative concentration pathways RCP2.6, RCP4.5, RCP6.0, RCP8.5. Each population simulation was repeated 10,000 times. Of the 8 Boulder Model simulations, 1 increased (+29.10%, 3 stayed approximately stable (+2.45%, +0.05%, -0.03%, and 4 simulations decreased substantially (-44.10%, -44.70%, -44.95%, -78.85%. All General Model simulations for western North America decreased by >90% (-93.75%, -96.70%, -96.70%, -98.75%. These results suggest that a changing climate in western North America has the potential to quickly erode some forest bat populations including species of conservation concern, such as fringed myotis.

  11. Environmental imperatives reconsidered: demographic crises in western North America during the medieval climatic anomaly.

    Science.gov (United States)

    Jones, T L; Brown, G M; Raab, L M; McVickar, J L; Spaulding, W G; Kennett, D J; York, A; Wlaker, P L

    1999-04-01

    Review of late Holocene paleoenvironmental and cultural sequences from four regions of western North America show striking correlations between drought and changes in subsistence, population, exchange, health, and interpersonal violence during the Medieval Climatic Anomaly (A.D. 800-1350). While ultimate causality is difficult to identify in the archaeological record, synchrony of the environmental and cultural changes and the negative character of many human responses--increased interpersonal violence, deterioration of long-distance exchange relationships, and regional abandonments--suggest widespread demographic crises caused by decreased environmental productivity. The medieval droughts occurred at a unique juncture in the demographic history of western North America when unusually large populations of both hunter-gathers and agriculturalists had evolved highly intensified economies that put them in unprecedented ecological jeopardy. Long-term patterns in the archaeological record are inconsistent with the predicted outcomes of simple adaptation or continuous economic intensification, suggesting that in this instance environmental dynamics played a major role in cultural transformations across a wide expanse of western North America among groups with diverse subsistence strategies. These events suggest that environment should not be overlooked as a potential cause of prehistoric culture change.

  12. Holocene climate variability and oceanographic changes off western South Africa

    Science.gov (United States)

    Zhao, Xueqin; Dupont, Lydie; E Meadows, Michael; Schefuß, Enno; Bouimetarhan, Ilham; Wefer, Gerold

    2017-04-01

    South Africa is located at a critical transition zone between subtropical and warm-temperate climate zones influenced by the Indian and Atlantic oceans. Presently, the seasonal changes of atmospheric and oceanic systems induce a pronounced rainfall seasonality comprised of two different rainfall zones over South Africa. How did this seasonality develop during the Holocene? To obtain a better understanding of how South African climates have evolved during the Holocene, we conduct a comprehensive spatial-temporal approach including pollen and dinoflagellate cyst records from marine sediment samples retrieved from the Namaqualand mudbelt, a Holocene terrigenous mud deposit on the shelf of western South Africa. The representation of different vegetation communities in western South Africa is assessed through pollen analysis of surface sediments. This approach allows for climate reconstructions of the summer rainfall zone (SRZ) using Group 1 (Poaceae, Cyperaceae, Phragmites-type and Typha) and winter rainfall zone (WRZ) using Group 2 (Restionaceae, Ericaceae, Anthospermum, Stoebe/Elytropappus-type, Cliffortia, Passerina, Artemisia-type and Pentzia-type) from a single marine archive. The fossil pollen data from gravity core GeoB8331-4 indicate contrasting climate patterns in the SRZ and WRZ especially during the early and middle Holocene. The rainfall amount in the SRZ is dominated by insolation forcing, while in the WRZ it is mainly attributed to the latitudinal position of the southern westerlies. Dinoflagellate cyst data show significantly different oceanographic conditions associated with climate changes on land. High percentages of autotrophic taxa like Operculodinium centrocarpum and Spiniferites spp. indicate warm and stratified conditions during the early Holocene, suggesting reduced upwelling. In contrast, the middle Holocene is characterized by a strong increase in heterotrophic taxa in particular Lejeunecysta paratenella and Echinidinium spp., indicating cool

  13. Natural gas commercialization in South America and its role as a regional integration factor

    International Nuclear Information System (INIS)

    Stanton, Ed; Rotte, Jooste

    1994-01-01

    This paper reviews the development of the existing natural gas businesses in various parts of the world. Lessons that have been learnt are used as pointers to assist in further development of the gas potential in South America. The healthy prospects for gas in South America are reviewed together with the provisions that are essential for gas business development in the future. (author). 1 fig

  14. Natural gas commercialization in South America and its role as a regional integration factor

    Energy Technology Data Exchange (ETDEWEB)

    Stanton, Ed; Rotte, Jooste [Shell International Gas (Brazil)

    1994-12-31

    This paper reviews the development of the existing natural gas businesses in various parts of the world. Lessons that have been learnt are used as pointers to assist in further development of the gas potential in South America. The healthy prospects for gas in South America are reviewed together with the provisions that are essential for gas business development in the future. (author). 1 fig.

  15. Phylogenetic evidence of a new canine distemper virus lineage among domestic dogs in Colombia, South America.

    Science.gov (United States)

    Espinal, Maria A; Díaz, Francisco J; Ruiz-Saenz, Julian

    2014-08-06

    Canine distemper virus (CDV) is a highly contagious viral disease of carnivores affecting both wild and domestic populations. The hemagglutinin gene, encoding for the attachment protein that determines viral tropism, shows high heterogeneity among strains, allowing for the distinction of ten different lineages distributed worldwide according to a geographic pattern. We obtained the sequences of the full-length H gene of 15 wild-type CDV strains circulating in domestic dog populations from the Aburrá Valley, Colombia. A phylogenetic analysis of H gene nucleotide sequences from Colombian CDV viruses along with field isolates from different geographic regions and vaccine strains was performed. Colombian wild-type viruses formed a distinct monophyletic cluster clearly separated from the previously identified wild-type and vaccine lineages, suggesting that a novel genetic variant, quite different from vaccines and other lineages, is circulating among dog populations in the Aburrá Valley. We propose naming this new lineage as "South America 3". This information indicates that there are at least three different CDV lineages circulating in domestic and wild carnivore populations in South America. The first one, renamed Europe/South America 1, circulates in Brazil and Uruguay; the second, South America 2, appears to be restricted to Argentina; and the third, South America 3, which comprises all the strains characterized in this study, may also be circulating in other northern countries of South America. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Radon exposure in abandoned metalliferous mines of South America

    International Nuclear Information System (INIS)

    Silva, A.A.R. da; Umisedo, N.; Yoshimura, E.M.; Anjos, R.M.; Valladares, D.L.; Velasco, H.; Rizzotto, M.

    2011-01-01

    Since the days of the Spanish and Portuguese conquerors, South America has been closely associated with the metalliferous ore mining. Gold, silver, tin, lead, tungsten, nickel, copper, and palladium ores have been explored over the last centuries. In addition, there has also been the development and promotion of other economic activities related to mining, as the underground mine tourism. A few works have been published on radon levels in the South American mining. In this study, we investigated the radon transport process and its health hazard in two exhausted and abandoned mines in San Luis Province, Argentina. These mines were chosen because they have different physical configurations in their cavities, features which can affect the air flow patterns and radon concentrations. La Carolina gold mine (32 deg 48' 0'' S, 66 deg 60' 0'' W) is currently a blind end system, corresponding to a horizontal excavation into the side of a mountain, with only a main adit. Los Condores wolfram mine (32 deg 33' 25'' S, 65 deg 15' 20'' W) is also a horizontal excavation into the side of a mountain, but has a vertical output (a shaft) at the end of the main gallery. Three different experimental methodologies were used. Radon concentration measurements were performed by CR-39 nuclear track detectors. The distribution of natural radionuclide activities ( 40 K, 232 Th and 238 U) was determined from rock samples collected along their main adits, using in laboratory gamma-ray spectrometry. The external gamma dose rate was evaluated using thermoluminescent dosimeters and a portable survey meter. The values for the 222 Rn concentration ranged from 0.43 ± 0.04 to 1.48 ± 0.12 kBq/m 3 in the Los Condores wolfram mine and from 1.8 ± 0.1 to 6.0±0.5 kBq/m 3 in the La Carolina gold mine, indicating that, in this mine, the radon levels exceed up to four times the action level of 1.5 kBq/m 3 recommended by the ICRP. The patterns of the radon transport process revealed that the La Carolina

  17. Stomach cancer burden in Central and South America.

    Science.gov (United States)

    Sierra, Monica S; Cueva, Patricia; Bravo, Luis Eduardo; Forman, David

    2016-09-01

    Stomach cancer mortality rates in Central and South America (CSA) are among the highest in the world. We describe the current burden of stomach cancer in CSA. We obtained regional and national-level cancer incidence data from 48 population-based registries (13 countries) and nation-wide cancer deaths from WHO's mortality database (18 countries). We estimated world population age-standardized incidence (ASR) and mortality (ASMR) rates per 100,000 and estimated annual percent change to describe time trends. Stomach cancer was among the 5 most frequently diagnosed cancers and a leading cause of cancer mortality. Between CSA countries, incidence varied by 6-fold and mortality by 5-6-fold. Males had up to 3-times higher rates than females. From 2003 to 2007, the highest ASRs were in Chile, Costa Rica, Colombia, Ecuador, Brazil and Peru (males: 19.2-29.1, females: 9.7-15.1). The highest ASMRs were in Chilean, Costa Rican, Colombian and Guatemalan males (17.4-24.6) and in Guatemalan, Ecuadorian and Peruvian females (10.5-17.1). From 1997 to 2008, incidence declined by 4% per year in Brazil, Chile and Costa Rica; mortality declined by 3-4% in Costa Rica and Chile. 60-96% of all the cancer cases were unspecified in relation to gastric sub-site but, among those specified, non-cardia cancers occurred 2-13-times more frequently than cardia cancers. The variation in rates may reflect differences in the prevalence of Helicobacter pylori infection and other risk factors. High mortality may additionally reflect deficiencies in healthcare access. The high proportion of unspecified cases calls for improving cancer registration processes. Copyright © 2015 International Agency for Research on Cancer. Published by Elsevier Ltd.. All rights reserved.

  18. Prostate cancer burden in Central and South America.

    Science.gov (United States)

    Sierra, Mónica S; Soerjomataram, Isabelle; Forman, David

    2016-09-01

    The incidence of prostate cancer has increased in Central and South America (CSA) in the last few decades. We describe the geographical patterns and trends of prostate cancer in CSA. We obtained regional and national-level cancer incidence data from 48 population-based registries in 13 countries and nation-wide cancer deaths from the WHO mortality database for 18 countries. We estimated world population age-standardized incidence (ASR) and mortality (ASMR) rates per 100,000 person-years for 2003-2007 and the estimated annual percent change (EAPC) to describe time trends. Prostate cancer was the most common cancer diagnosis and one of the leading causes of cancer deaths among males in most CSA countries. From 2003-2007, ASRs varied between countries (6-fold) and within countries (Brazil: 3-6-fold). French Guyana (147.1) and Brazil (91.4) had the highest ASRs whereas Mexico (28.9) and Cuba (24.3) had the lowest. ASMRs varied by 4-fold. Belize, Uruguay and Cuba (24.1-28.9) had the highest ASMRs while Peru, Nicaragua, and El Salvador (6.8-9.7) had the lowest. In Argentina, Brazil, Chile and Costa Rica prostate cancer incidence increased by 2.8-4.8% annually whereas mortality remained stable between 1997 and 2008. The geographic and temporal variation of prostate cancer rates observed in CSA may in part reflect differences in diagnostic and registration practices, healthcare access, treatment and death certification, and public awareness. The incidence of prostate cancer is expected to increase given recent early detection activities and increased public awareness; however, the impact of these factors on mortality remains to be elucidated. Copyright © 2016 International Agency for Research on Cancer. Published by Elsevier Ltd.. All rights reserved.

  19. Evaluation Metrics for Simulations of Tropical South America

    Science.gov (United States)

    Gallup, S.; Baker, I. T.; Denning, A. S.; Cheeseman, M.; Haynes, K. D.; Phillips, M.

    2017-12-01

    The evergreen broadleaf forest of the Amazon Basin is the largest rainforest on earth, and has teleconnections to global climate and carbon cycle characteristics. This region defies simple characterization, spanning large gradients in total rainfall and seasonal variability. Broadly, the region can be thought of as trending from light-limited in its wettest areas to water-limited near the ecotone, with individual landscapes possibly exhibiting the characteristics of either (or both) limitations during an annual cycle. A basin-scale classification of mean behavior has been elusive, and ecosystem response to seasonal cycles and anomalous drought events has resulted in some disagreement in the literature, to say the least. However, new observational platforms and instruments make characterization of the heterogeneity and variability more feasible.To evaluate simulations of ecophysiological function, we develop metrics that correlate various observational products with meteorological variables such as precipitation and radiation. Observations include eddy covariance fluxes, Solar Induced Fluorescence (SIF, from GOME2 and OCO2), biomass and vegetation indices. We find that the modest correlation between SIF and precipitation decreases with increasing annual precipitation, although the relationship is not consistent between products. Biomass increases with increasing precipitation. Although vegetation indices are generally correlated with biomass and precipitation, they can saturate or experience retrieval issues during cloudy periods.Using these observational products and relationships, we develop a set of model evaluation metrics. These metrics are designed to call attention to models that get "the right answer only if it's for the right reason," and provide an opportunity for more critical evaluation of model physics. These metrics represent a testbed that can be applied to multiple models as a means to evaluate their performance in tropical South America.

  20. Diabetes in South and Central America: an update.

    Science.gov (United States)

    Aschner, Pablo; Aguilar-Salinas, Carlos; Aguirre, Loreto; Franco, Laercio; Gagliardino, Juan Jose; de Lapertosa, Sylvia Gorban; Seclen, Segundo; Vinocour, Mary

    2014-02-01

    The estimated population of the South and Central America (SACA) Region is 467.6 million and 64% is in the age range of 20-79 years but the population pyramid and age distribution are changing. The average prevalence of diabetes in the Region is 8.0% and is expected to reach 9.8% by the year 2035. Prevalence is much lower in rural settings than in urban and the differences attributed to lifestyle changes may be a target for intervention. The indigenous population is a particularly vulnerable group needing special attention. On average, 24% of the adult cases with diabetes are undiagnosed but in some countries this is still as high as 50%. Health expenditure due to diabetes in the Region is around 9% of the global total. Inadequate glycemic control, defined as HbA1c >7%, is a strong predictor of chronic complications which increase resource use in the Region and less than half of the patients enrolled in diabetes care programmes are at target. Fifty percent or more of the adult population is overweight/obese and around one third of the adult population has metabolic syndrome using regional cutoffs for waist circumference. The number of people with IGT is almost equal to those with diabetes presenting an additional challenge for prevention. Children with type 1 diabetes represent only 0.2% of the total population with diabetes but the incidence may be increasing. In many places they have limited access to insulin, and even when available, it is not used appropriately. The available epidemiological data provide the background to act in developing national diabetes programmes which integrate diabetes care with cardiovascular prevention and promote diabetes prevention as well. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  1. Successful adaptation of a research methods course in South America.

    Science.gov (United States)

    Tamariz, Leonardo; Vasquez, Diego; Loor, Cecilia; Palacio, Ana

    2017-01-01

    South America has low research productivity. The lack of a structured research curriculum is one of the barriers to conducting research. To report our experience adapting an active learning-based research methods curriculum to improve research productivity at a university in Ecuador. We used a mixed-method approach to test the adaptation of the research curriculum at Universidad Catolica Santiago de Guayaquil. The curriculum uses a flipped classroom and active learning approach to teach research methods. When adapted, it was longitudinal and had 16-hour programme of in-person teaching and a six-month follow-up online component. Learners were organized in theme groups according to interest, and each group had a faculty leader. Our primary outcome was research productivity, which was measured by the succesful presentation of the research project at a national meeting, or publication in a peer-review journal. Our secondary outcomes were knowledge and perceived competence before and after course completion. We conducted qualitative interviews of faculty members and students to evaluate themes related to participation in research. Fifty university students and 10 faculty members attended the course. We had a total of 15 groups. Both knowledge and perceived competence increased by 17 and 18 percentage points, respectively. The presentation or publication rate for the entire group was 50%. The qualitative analysis showed that a lack of research culture and curriculum were common barriers to research. A US-based curriculum can be successfully adapted in low-middle income countries. A research curriculum aids in achieving pre-determined milestones. UCSG: Universidad Catolica Santiago de Guayaquil; UM: University of Miami.

  2. Performance of a multi-RCM ensemble for South Eastern South America

    Energy Technology Data Exchange (ETDEWEB)

    Carril, A.F.; Menendez, C.G.; Salio, P. [Ciudad Universitaria, Ciudad Autonoma de Buenos Aires, Centro de Investigaciones del Mar y la Atmosfera (CIMA), CONICET-UBA, Buenos Aires (Argentina); Universidad de Buenos Aires, Departamento de Ciencias de la Atmosfera y los Oceanos (DCAO), FCEN, Buenos Aires (Argentina); UMI IFAECI/CNRS, Buenos Aires (Argentina); Remedio, A.R.C.; Jacob, D.; Pfeifer, S. [Max Planck Institute for Meteorology (MPI-M), Hamburg (Germany); Robledo, F.; Tencer, B. [Universidad de Buenos Aires, Departamento de Ciencias de la Atmosfera y los Oceanos (DCAO), FCEN, Buenos Aires (Argentina); Soerensson, A.; Zaninelli, P. [Ciudad Universitaria, Ciudad Autonoma de Buenos Aires, Centro de Investigaciones del Mar y la Atmosfera (CIMA), CONICET-UBA, Buenos Aires (Argentina); UMI IFAECI/CNRS, Buenos Aires (Argentina); Boulanger, J.P. [LOCEAN, UMR CNRS/IRD/UPMC, Paris (France); Castro, M. de; Sanchez, E. [Universidad de Castilla-La Mancha (UCLM), Toledo (Spain); Le Treut, H.; Li, L.Z.X. [Sciences de l' Environnement en Ile de France, Laboratoire de Meteorologie Dynamique (LMD), Institut-Pierre-Simon-Laplace et Ecole Doctorale, Paris (France); Penalba, O.; Rusticucci, M. [Universidad de Buenos Aires, Departamento de Ciencias de la Atmosfera y los Oceanos (DCAO), FCEN, Buenos Aires (Argentina); UMI IFAECI/CNRS, Buenos Aires (Argentina); Samuelsson, P. [Swedish Meteorological and Hydrological Institute (SMHI), Norrkoeping (Sweden)

    2012-12-15

    The ability of four regional climate models to reproduce the present-day South American climate is examined with emphasis on La Plata Basin. Models were integrated for the period 1991-2000 with initial and lateral boundary conditions from ERA-40 Reanalysis. The ensemble sea level pressure, maximum and minimum temperatures and precipitation are evaluated in terms of seasonal means and extreme indices based on a percentile approach. Dispersion among the individual models and uncertainties when comparing the ensemble mean with different climatologies are also discussed. The ensemble mean is warmer than the observations in South Eastern South America (SESA), especially for minimum winter temperatures with errors increasing in magnitude towards the tails of the distributions. The ensemble mean reproduces the broad spatial pattern of precipitation, but overestimates the convective precipitation in the tropics and the orographic precipitation along the Andes and over the Brazilian Highlands, and underestimates the precipitation near the monsoon core region. The models overestimate the number of wet days and underestimate the daily intensity of rainfall for both seasons suggesting a premature triggering of convection. The skill of models to simulate the intensity of convective precipitation in summer in SESA and the variability associated with heavy precipitation events (the upper quartile daily precipitation) is far from satisfactory. Owing to the sparseness of the observing network, ensemble and observations uncertainties in seasonal means are comparable for some regions and seasons. (orig.)

  3. Avian mercury exposure and toxicological risk across western North America: A synthesis

    Science.gov (United States)

    Ackerman, Joshua T.; Eagles-Smith, Collin A.; Herzog, Mark; Hartman, Christopher; Peterson, Sarah; Evers, David C.; Jackson, Allyson K.; Elliott, John E.; Vander Pol, Stacy S.; Bryan, Colleen E.

    2016-01-01

    Methylmercury contamination of the environment is an important issue globally, and birds are useful bioindicators for mercury monitoring programs. The available data on mercury contamination of birds in western North America were synthesized. Original data from multiple databases were obtained and a literature review was conducted to obtain additional mercury concentrations. In total, 29219 original bird mercury concentrations from 225 species were compiled, and an additional 1712 mean mercury concentrations, representing 19998 individuals and 176 species, from 200 publications were obtained. To make mercury data comparable across bird tissues, published equations of tissue mercury correlations were used to convert all mercury concentrations into blood-equivalent mercury concentrations. Blood-equivalent mercury concentrations differed among species, foraging guilds, habitat types, locations, and ecoregions. Piscivores and carnivores exhibited the greatest mercury concentrations, whereas herbivores and granivores exhibited the lowest mercury concentrations. Bird mercury concentrations were greatest in ocean and salt marsh habitats and lowest in terrestrial habitats. Bird mercury concentrations were above toxicity benchmarks in many areas throughout western North America, and multiple hotspots were identified. Additionally, published toxicity benchmarks established in multiple tissues were summarized and translated into a common blood-equivalent mercury concentration. Overall, 66% of birds sampled in western North American exceeded a blood-equivalent mercury concentration of 0.2 μg/g wet weight (ww; above background levels), which is the lowest-observed effect level, 28% exceeded 1.0 μg/g ww (moderate risk), 8% exceeded 3.0 μg/g ww (high risk), and 4% exceeded 4.0 μg/g ww (severe risk). Mercury monitoring programs should sample bird tissues, such as adult blood and eggs, that are most-easily translated into tissues with well-developed toxicity benchmarks and that

  4. What Do We Know about the Development of Creativity in South America?

    Science.gov (United States)

    Preiss, David D.; Grau, Valeska; Ortiz, Dominga; Bernardino, Michelle

    2016-01-01

    We review recent research about the development of creativity in South America focusing on studies of individual differences in creativity and educational and developmental studies of children and adolescents' creativity. Most South American researchers are influenced by mainstream psychometric approaches, although computational and cultural…

  5. Hydrovatus caraibus Sharp, 1882 (Dytiscidae, Hydroporinae, Hydrovatini new for the fauna of South America

    Directory of Open Access Journals (Sweden)

    Benetti, C. J.

    2003-11-01

    Full Text Available The species Hydrovatus caraibus Sharp, 1882 is recorded for the first time for South America, after the recollection of specimens of this species in the municipality of Gramado, State of Rio Grande do Sul, Brazil. The range of distribution of the species, previously restricted to the Caribbean, is now extended to the latitude 29º 26’ South, approximately.

  6. 7 CFR 319.56-26 - Melon and watermelon from certain countries in South America.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Melon and watermelon from certain countries in South... and Vegetables § 319.56-26 Melon and watermelon from certain countries in South America. (a) Cantaloupe and watermelon from Ecuador. Cantaloupe (Cucumis melo) and watermelon (fruit) (Citrullus lanatus...

  7. The Paleo-Indian Entry into South America According to Mitogenomes.

    Science.gov (United States)

    Brandini, Stefania; Bergamaschi, Paola; Cerna, Marco Fernando; Gandini, Francesca; Bastaroli, Francesca; Bertolini, Emilie; Cereda, Cristina; Ferretti, Luca; Gómez-Carballa, Alberto; Battaglia, Vincenza; Salas, Antonio; Semino, Ornella; Achilli, Alessandro; Olivieri, Anna; Torroni, Antonio

    2018-02-01

    Recent and compelling archaeological evidence attests to human presence ∼14.5 ka at multiple sites in South America and a very early exploitation of extreme high-altitude Andean environments. Considering that, according to genetic evidence, human entry into North America from Beringia most likely occurred ∼16 ka, these archeological findings would imply an extremely rapid spread along the double continent. To shed light on this issue from a genetic perspective, we first completely sequenced 217 novel modern mitogenomes of Native American ancestry from the northwestern area of South America (Ecuador and Peru); we then evaluated them phylogenetically together with other available mitogenomes (430 samples, both modern and ancient) from the same geographic area and, finally, with all closely related mitogenomes from the entire double continent. We detected a large number (N = 48) of novel subhaplogroups, often branching into further subclades, belonging to two classes: those that arose in South America early after its peopling and those that instead originated in North or Central America and reached South America with the first settlers. Coalescence age estimates for these subhaplogroups provide time boundaries indicating that early Paleo-Indians probably moved from North America to the area corresponding to modern Ecuador and Peru over the short time frame of ∼1.5 ka comprised between 16.0 and 14.6 ka. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  8. Heritage and the Development of Stellenbosch, Western Cape, South Africa

    Directory of Open Access Journals (Sweden)

    Fabio Todeschini

    2017-06-01

    Full Text Available The jurisdiction of Stellenbosch, located adjacent to, but outside of, the Cape Town metropolitan area in the Western Cape Province of South Africa, comprises over one thousand square kilometers of landscapes spanning: spectacular mountain wilderness areas; many productive rural valleys that are an integral part of the celebrated Cape Winelands; and a number of historic, characterful urban centres founded during the 17th century. Overall, this blend of domains attracts increasing numbers of tourists, while the places are also home to a growing population. The pressures for change and growth are significant: so is the need for appropriate policies and plans in the longer-term public interest. The authors report on a three-year project they are conducting for the local authority that focuses on the definition of the natural and cultural heritage and, in principle, on how development should be channelled.

  9. Genomic Insights into the Ancestry and Demographic History of South America

    Science.gov (United States)

    Homburger, Julian R.; Moreno-Estrada, Andrés; Gignoux, Christopher R.; Nelson, Dominic; Sanchez, Elena; Ortiz-Tello, Patricia; Pons-Estel, Bernardo A.; Acevedo-Vasquez, Eduardo; Miranda, Pedro; Langefeld, Carl D.; Gravel, Simon; Alarcón-Riquelme, Marta E.; Bustamante, Carlos D.

    2015-01-01

    South America has a complex demographic history shaped by multiple migration and admixture events in pre- and post-colonial times. Settled over 14,000 years ago by Native Americans, South America has experienced migrations of European and African individuals, similar to other regions in the Americas. However, the timing and magnitude of these events resulted in markedly different patterns of admixture throughout Latin America. We use genome-wide SNP data for 437 admixed individuals from 5 countries (Colombia, Ecuador, Peru, Chile, and Argentina) to explore the population structure and demographic history of South American Latinos. We combined these data with population reference panels from Africa, Asia, Europe and the Americas to perform global ancestry analysis and infer the subcontinental origin of the European and Native American ancestry components of the admixed individuals. By applying ancestry-specific PCA analyses we find that most of the European ancestry in South American Latinos is from the Iberian Peninsula; however, many individuals trace their ancestry back to Italy, especially within Argentina. We find a strong gradient in the Native American ancestry component of South American Latinos associated with country of origin and the geography of local indigenous populations. For example, Native American genomic segments in Peruvians show greater affinities with Andean indigenous peoples like Quechua and Aymara, whereas Native American haplotypes from Colombians tend to cluster with Amazonian and coastal tribes from northern South America. Using ancestry tract length analysis we modeled post-colonial South American migration history as the youngest in Latin America during European colonization (9–14 generations ago), with an additional strong pulse of European migration occurring between 3 and 9 generations ago. These genetic footprints can impact our understanding of population-level differences in biomedical traits and, thus, inform future medical

  10. Genomic Insights into the Ancestry and Demographic History of South America.

    Science.gov (United States)

    Homburger, Julian R; Moreno-Estrada, Andrés; Gignoux, Christopher R; Nelson, Dominic; Sanchez, Elena; Ortiz-Tello, Patricia; Pons-Estel, Bernardo A; Acevedo-Vasquez, Eduardo; Miranda, Pedro; Langefeld, Carl D; Gravel, Simon; Alarcón-Riquelme, Marta E; Bustamante, Carlos D

    2015-12-01

    South America has a complex demographic history shaped by multiple migration and admixture events in pre- and post-colonial times. Settled over 14,000 years ago by Native Americans, South America has experienced migrations of European and African individuals, similar to other regions in the Americas. However, the timing and magnitude of these events resulted in markedly different patterns of admixture throughout Latin America. We use genome-wide SNP data for 437 admixed individuals from 5 countries (Colombia, Ecuador, Peru, Chile, and Argentina) to explore the population structure and demographic history of South American Latinos. We combined these data with population reference panels from Africa, Asia, Europe and the Americas to perform global ancestry analysis and infer the subcontinental origin of the European and Native American ancestry components of the admixed individuals. By applying ancestry-specific PCA analyses we find that most of the European ancestry in South American Latinos is from the Iberian Peninsula; however, many individuals trace their ancestry back to Italy, especially within Argentina. We find a strong gradient in the Native American ancestry component of South American Latinos associated with country of origin and the geography of local indigenous populations. For example, Native American genomic segments in Peruvians show greater affinities with Andean indigenous peoples like Quechua and Aymara, whereas Native American haplotypes from Colombians tend to cluster with Amazonian and coastal tribes from northern South America. Using ancestry tract length analysis we modeled post-colonial South American migration history as the youngest in Latin America during European colonization (9-14 generations ago), with an additional strong pulse of European migration occurring between 3 and 9 generations ago. These genetic footprints can impact our understanding of population-level differences in biomedical traits and, thus, inform future medical

  11. Genomic Insights into the Ancestry and Demographic History of South America.

    Directory of Open Access Journals (Sweden)

    Julian R Homburger

    2015-12-01

    Full Text Available South America has a complex demographic history shaped by multiple migration and admixture events in pre- and post-colonial times. Settled over 14,000 years ago by Native Americans, South America has experienced migrations of European and African individuals, similar to other regions in the Americas. However, the timing and magnitude of these events resulted in markedly different patterns of admixture throughout Latin America. We use genome-wide SNP data for 437 admixed individuals from 5 countries (Colombia, Ecuador, Peru, Chile, and Argentina to explore the population structure and demographic history of South American Latinos. We combined these data with population reference panels from Africa, Asia, Europe and the Americas to perform global ancestry analysis and infer the subcontinental origin of the European and Native American ancestry components of the admixed individuals. By applying ancestry-specific PCA analyses we find that most of the European ancestry in South American Latinos is from the Iberian Peninsula; however, many individuals trace their ancestry back to Italy, especially within Argentina. We find a strong gradient in the Native American ancestry component of South American Latinos associated with country of origin and the geography of local indigenous populations. For example, Native American genomic segments in Peruvians show greater affinities with Andean indigenous peoples like Quechua and Aymara, whereas Native American haplotypes from Colombians tend to cluster with Amazonian and coastal tribes from northern South America. Using ancestry tract length analysis we modeled post-colonial South American migration history as the youngest in Latin America during European colonization (9-14 generations ago, with an additional strong pulse of European migration occurring between 3 and 9 generations ago. These genetic footprints can impact our understanding of population-level differences in biomedical traits and, thus, inform

  12. Conservation of placentation during the tertiary radiation of mammals in South America

    DEFF Research Database (Denmark)

    Carter, Anthony Michael; Mess, Andrea Maria

    2013-01-01

    The eutherian placenta is considered to possess great plasticity, but it is not clear how this variation reflects adaptation to different ecological niches. Because South America was isolated for most of the Tertiary, it represents a natural laboratory to examine this question. We here describe...... placentation in three South American groups: Xenarthra have been part of the fauna from at least the mid-Paleocene whereas caviomorph rodents and Neotropical primates are each derived from a single founder that reached South America in the Eocene and Oligocene, respectively. The common ancestor of Xenarthra....... This pattern was present before arrival of these rodents in South America and enabled a successful radiation especially during the spread of grasslands. Neotropical primates have haemochorial, trabecular placentas with a specialized maternal blood supply; a pattern that contrasts with that of Old World monkeys...

  13. Neurocysticercosos in South-Central America and the Indian Subcontinent: a comparative evaluation

    Directory of Open Access Journals (Sweden)

    Gagandeep Singh

    1997-09-01

    Full Text Available Neurocysticercosis is an important public health problem in South-Central America and South Asia. A review of the differences in epidemiological and clinical attributes of cysticercosis and taeniasis in South Central America and India, respectively, is undertaken in the present communication. Intestinal taeniasis is hyperendemic in several American countries. In comparison, the prevalence of Taenia solium infestation is lower in India. The clinical manifestations in several American neurocysticercosis series comprise epilepsy, intracranial hypertension and meningeal - racemose cysticercosis, in roughly equal proportions. An overwhelming majority of the Indian subjects present with seizures. The commonest pathological substrate of the disorder in Indian patients is the solitary parenchymal degenerating cyst. The reasons for the predominance of solitary forms in India, and of multilesional forms in South Central America are discussed. The magnitude of Taenia solium infestation and the frequency of pork consumption in a given population appear to influence the quantum of cyst load in affected individuals.

  14. Radon exposure in abandoned metalliferous mines of South America

    Energy Technology Data Exchange (ETDEWEB)

    Silva, A.A.R. da; Umisedo, N.; Yoshimura, E.M. [Universidade de Sao Paulo (IF/USP), SP (Brazil). Inst. de Fisica. Lab. de Dosimetria; Anjos, R.M. [Universidade Federal Fluminense (LARA/UFF), Niteroi, RJ (Brazil). Inst. de Fisica. Lab. de Radioecologia; Valladares, D.L.; Velasco, H.; Rizzotto, M. [Universidad Nacional de San Luis (UNSL) (Argentina). Inst. de Matematica Aplicada San Luis

    2011-07-01

    Since the days of the Spanish and Portuguese conquerors, South America has been closely associated with the metalliferous ore mining. Gold, silver, tin, lead, tungsten, nickel, copper, and palladium ores have been explored over the last centuries. In addition, there has also been the development and promotion of other economic activities related to mining, as the underground mine tourism. A few works have been published on radon levels in the South American mining. In this study, we investigated the radon transport process and its health hazard in two exhausted and abandoned mines in San Luis Province, Argentina. These mines were chosen because they have different physical configurations in their cavities, features which can affect the air flow patterns and radon concentrations. La Carolina gold mine (32 deg 48' 0'' S, 66 deg 60' 0'' W) is currently a blind end system, corresponding to a horizontal excavation into the side of a mountain, with only a main adit. Los Condores wolfram mine (32 deg 33' 25'' S, 65 deg 15' 20'' W) is also a horizontal excavation into the side of a mountain, but has a vertical output (a shaft) at the end of the main gallery. Three different experimental methodologies were used. Radon concentration measurements were performed by CR-39 nuclear track detectors. The distribution of natural radionuclide activities ({sup 40}K, {sup 232}Th and {sup 238}U) was determined from rock samples collected along their main adits, using in laboratory gamma-ray spectrometry. The external gamma dose rate was evaluated using thermoluminescent dosimeters and a portable survey meter. The values for the {sup 222}Rn concentration ranged from 0.43 {+-} 0.04 to 1.48 {+-} 0.12 kBq/m{sup 3} in the Los Condores wolfram mine and from 1.8 {+-} 0.1 to 6.0{+-}0.5 kBq/m{sup 3} in the La Carolina gold mine, indicating that, in this mine, the radon levels exceed up to four times the action level of 1.5 kBq/m{sup 3

  15. Past climate change and plant evolution in Western North America: a case study in Rosaceae.

    Science.gov (United States)

    Töpel, Mats; Antonelli, Alexandre; Yesson, Chris; Eriksen, Bente

    2012-01-01

    Species in the ivesioid clade of Potentilla (Rosaceae) are endemic to western North America, an area that underwent widespread aridification during the global temperature decrease following the Mid-Miocene Climatic Optimum. Several morphological features interpreted as adaptations to drought are found in the clade, and many species occupy extremely dry habitats. Recent phylogenetic analyses have shown that the sister group of this clade is Potentilla section Rivales, a group with distinct moist habitat preferences. This has led to the hypothesis that the ivesioids (genera Ivesia, Horkelia and Horkeliella) diversified in response to the late Tertiary aridification of western North America. We used phyloclimatic modeling and a fossil-calibrated dated phylogeny of the family Rosaceae to investigate the evolution of the ivesioid clade. We have combined occurrence- and climate data from extant species, and used ancestral state reconstruction to model past climate preferences. These models have been projected into paleo-climatic scenarios in order to identify areas where the ivesioids may have occurred. Our analysis suggests a split between the ivesioids and Potentilla sect. Rivales around Late Oligocene/Early Miocene (∼23 million years ago, Ma), and that the ivesioids then diversified at a time when summer drought started to appear in the region. The clade is inferred to have originated on the western slopes of the Rocky Mountains from where a westward range expansion to the Sierra Nevada and the coast of California took place between ∼12-2 Ma. Our results support the idea that climatic changes in southwestern North America have played an important role in the evolution of the local flora, by means of in situ adaptation followed by diversification.

  16. Past climate change and plant evolution in Western North America: a case study in Rosaceae.

    Directory of Open Access Journals (Sweden)

    Mats Töpel

    Full Text Available Species in the ivesioid clade of Potentilla (Rosaceae are endemic to western North America, an area that underwent widespread aridification during the global temperature decrease following the Mid-Miocene Climatic Optimum. Several morphological features interpreted as adaptations to drought are found in the clade, and many species occupy extremely dry habitats. Recent phylogenetic analyses have shown that the sister group of this clade is Potentilla section Rivales, a group with distinct moist habitat preferences. This has led to the hypothesis that the ivesioids (genera Ivesia, Horkelia and Horkeliella diversified in response to the late Tertiary aridification of western North America. We used phyloclimatic modeling and a fossil-calibrated dated phylogeny of the family Rosaceae to investigate the evolution of the ivesioid clade. We have combined occurrence- and climate data from extant species, and used ancestral state reconstruction to model past climate preferences. These models have been projected into paleo-climatic scenarios in order to identify areas where the ivesioids may have occurred. Our analysis suggests a split between the ivesioids and Potentilla sect. Rivales around Late Oligocene/Early Miocene (∼23 million years ago, Ma, and that the ivesioids then diversified at a time when summer drought started to appear in the region. The clade is inferred to have originated on the western slopes of the Rocky Mountains from where a westward range expansion to the Sierra Nevada and the coast of California took place between ∼12-2 Ma. Our results support the idea that climatic changes in southwestern North America have played an important role in the evolution of the local flora, by means of in situ adaptation followed by diversification.

  17. Drought variation of western Chinese Loess Plateau since 1568 and its linkages with droughts in western North America

    Science.gov (United States)

    Fang, Keyan; Guo, Zhengtang; Chen, Deliang; Linderholm, Hans W.; Li, Jinbao; Zhou, Feifei; Guo, Guoyang; Dong, Zhipeng; Li, Yingjun

    2017-12-01

    Understanding long-term drought variations in the past can help to evaluate ongoing and future hydroclimate change in the arid western Chinese Loess Plateau (WCLP), a region with increasing demand for water resources due to the increasing population and socioeconomic activities. Here we present a new tree-ring chronology inform the WCLP, which shows coherent interannual variations with tree-ring chronologies from 7 neighboring areas across the WCLP, suggesting a common regional climate control over tree growth. However, considerable differences are observed among their interdecadal variations, which are likely due to growth disturbances at interdecadal timescales. To deal with this issue, we use a frequency based method to develop a composite tree-ring chronology from 401 tree-ring series from these 8 sites, which shows more pronounced interdecadal variability than a chronology developed using traditional methods. The composite tree-ring chronology is used to reconstruct the annual precipitation from previous August to current July from 1568 to 2012, extending about 50 years longer than the previous longest tree-ring reconstruction from the region. The driest epoch of our reconstruction is found in the 1920s-1930s, which matches well with droughts recorded in historical documents. Over the past four centuries, a strong resemblance between drought variability in the WCLP and western North America (WNA) is evident on multidecadal timescales, but this relationship breaks down on timescales shorter than about 50 years.

  18. Climate Risk Modelling of Balsam Woolly Adelgid Damage Severity in Subalpine Fir Stands of Western North America.

    Science.gov (United States)

    Hrinkevich, Kathryn H; Progar, Robert A; Shaw, David C

    2016-01-01

    The balsam woolly adelgid (Adelges piceae (Ratzeburg) (Homoptera: Adelgidae)) (BWA) is a nonnative, invasive insect that threatens Abies species throughout North America. It is well established in the Pacific Northwest, but continues to move eastward through Idaho and into Montana and potentially threatens subalpine fir to the south in the central and southern Rocky Mountains. We developed a climatic risk model and map that predicts BWA impacts to subalpine fir using a two-step process. Using 30-year monthly climate normals from sites with quantitatively derived BWA damage severity index values, we built a regression model that significantly explained insect damage. The sites were grouped into two distinct damage categories (high damage and mortality versus little or no mortality and low damage) and the model estimates for each group were used to designate distinct value ranges for four climatic risk categories: minimal, low, moderate, and high. We then calculated model estimates for each cell of a 4-kilometer resolution climate raster and mapped the risk categories over the entire range of subalpine fir in the western United States. The spatial variation of risk classes indicates a gradient of climatic susceptibility generally decreasing from the Olympic Peninsula in Washington and the Cascade Range in Oregon and Washington moving eastward, with the exception of some high risk areas in northern Idaho and western Montana. There is also a pattern of decreasing climatic susceptibility from north to south in the Rocky Mountains. Our study provides an initial step for modeling the relationship between climate and BWA damage severity across the range of subalpine fir. We showed that September minimum temperature and a metric calculated as the maximum May temperature divided by total May precipitation were the best climatic predictors of BWA severity. Although winter cold temperatures and summer heat have been shown to influence BWA impacts in other locations, these

  19. A habitat overlap analysis derived from Maxent for Tamarisk and the South-western Willow Flycatcher

    Science.gov (United States)

    Patricia York; Paul Evangelista; Sunil Kumar; James Graham; Curtis Flather; Thomas Stohlgren

    2011-01-01

    Biologic control of the introduced and invasive, woody plant tamarisk (Tamarix spp, saltcedar) in south-western states is controversial because it affects habitat of the federally endangered South-western Willow Flycatcher (Empidonax traillii extimus). These songbirds sometimes nest in tamarisk where floodplain-level invasion replaces native habitats. Biologic control...

  20. Thermodynamic and Dynamic Causes of Pluvial Conditions During the Last Glacial Maximum in Western North America

    Science.gov (United States)

    Morrill, Carrie; Lowry, Daniel P.; Hoell, Andrew

    2018-01-01

    During the last glacial period, precipitation minus evaporation increased across the currently arid western United States. These pluvial conditions have been commonly explained for decades by a southward deflection of the jet stream by the Laurentide Ice Sheet. Here analysis of state-of-the-art coupled climate models shows that effects of the Laurentide Ice Sheet on the mean circulation were more important than storm track changes in generating wet conditions. Namely, strong cooling by the ice sheet significantly reduced humidity over land, increasing moisture advection in the westerlies due to steepened humidity gradients. Additionally, the removal of moisture from the atmosphere by mass divergence associated with the subtropical high was diminished at the Last Glacial Maximum compared to present. These same dynamic and thermodynamic factors, working in the opposite direction, are projected to cause regional drying in western North America under increased greenhouse gas concentrations, indicating continuity from past to future in the mechanisms altering hydroclimate.

  1. A primer on the phylogeography of Lagothrix lagotricha (sensu Fooden) in northern South America.

    Science.gov (United States)

    Botero, Sergio; Stevenson, Pablo R; Di Fiore, Anthony

    2015-01-01

    The taxonomic history of the genus Lagothrix is complex, with molecular and morphological assessments giving conflicting results for the separation between its taxa. Phylogeographic studies of the most widely distributed species, Lagothrix lagotricha, have only been attempted recently and are limited to few individuals per collection site, many of which were captive making their geographical origin dubious. There is debate regarding the possibility of raising subspecies of Lagothrix lagotricha to the species level, therefore the geographical origin of samples is particularly relevant. In the present work we revisit the intraspecific phylogeography of L. lagotricha from northwestern South America, including the subspecies L. l. poeppiggi, L. l. lagotricha and L. l. lugens (sensu Fooden, 1963), using DNA sequence data from hypervariable region I of the mitochondrial control region (D-loop HVI). Our results suggest a complex picture in which there are well delimited evolutionary units that, nonetheless, do not correlate well with the morphological variation used to support the current delimitation of taxa. Additionally, we corroborate previous results showing a lack of reciprocal monophyly between the putative subspecies of Lagothrix lagotricha, and we propose that this may be due to ancestral polymorphism that has been maintained following the recent spread of woolly monkeys throughout the western Amazonian lowlands and into the inter-Andean region of Colombia. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. A history of Proterozoic terranes in southern South America: From Rodinia to Gondwana

    Directory of Open Access Journals (Sweden)

    C. Casquet

    2012-03-01

    Full Text Available The role played by Paleoproterozoic cratons in southern South America from the Mesoproterozoic to the Early Cambrian is reconsidered here. This period involved protracted continental amalgamation that led to formation of the supercontinent Rodinia, followed by Neoproterozoic continental break-up, with the consequent opening of Clymene and Iapetus oceans, and finally continental re-assembly as Gondwana through complex oblique collisions in the Late Neoproterozoic to Early Cambrian. The evidence for this is based mainly on a combination of precise U-Pb SHRMP dating and radiogenic isotope data for igneous and metamorphic rocks from a large area extending from the Rio de la Plata craton in the east to the Argentine Precordillera in the west and as far north as Arequipa in Peru. Our interpretation of the paleogeographical and geodynamic evolution invokes a hypothetical Paleoproterozoic block (MARA embracing basement ultimately older than 1.7 Ga in the Western Sierras Pampeanas (Argentina, the Arequipa block (Peru, the Rio Apa block (Brazil, and probably also the Paraguaia block (Bolivia.

  3. Presence of stratospheric humidity in the ozone column depletion on the west coast of South America

    International Nuclear Information System (INIS)

    Da Silva, M. Luis; Gutierrez, O. Luis; Morales, S. Luis; Universidad de Chile, Santiago; Torres, C. Arnaldo

    2006-01-01

    The ozone column depletion over the western coast of South America has been previously explained, based on the existence of winds in the area of the depletion, which cause compression and thinning of the ozone layer. However, the presence of humidity and methane transported by these winds to the stratosphere where the ozone depletion is present gives evidence that these compounds also participate in the depletion of the ozone layer. These two compounds, humidity and methane, are analysed during the ozone depletion of January, 1998. It is observed that when humidity presents fluctuations, ozone has fluctuations too. A maximum of humidity corresponds to a minimum of ozone, but there is a shift in altitude between them. This shift is observed in the stratosphere and upper troposphere and corresponds to approximately 500 m. It is important to point out that during this event El Nino was present and the sources of methane are the Amazon forest and the Pacific Ocean. The data for this study was obtained from NASA and HALOE

  4. Conservation of placentation during the tertiary radiation of mammals in South America.

    Science.gov (United States)

    Carter, Anthony Michael; Mess, Andrea Maria

    2013-05-01

    The eutherian placenta is considered to possess great plasticity, but it is not clear how this variation reflects adaptation to different ecological niches. Because South America was isolated for most of the Tertiary, it represents a natural laboratory to examine this question. We here describe placentation in three South American groups: Xenarthra have been part of the fauna from at least the mid-Paleocene whereas caviomorph rodents and Neotropical primates are each derived from a single founder that reached South America in the Eocene and Oligocene, respectively. The common ancestor of Xenarthra had a villous, haemochorial placenta, from which the labyrinthine, endotheliochorial placenta of sloths later evolved. Placentation in Caviomorpha follows an extraordinary stable pattern, characterized by a haemomonochorial, labyrinthine and highly lobed structure with specialized growing areas. This pattern was present before arrival of these rodents in South America and enabled a successful radiation especially during the spread of grasslands. Neotropical primates have haemochorial, trabecular placentas with a specialized maternal blood supply; a pattern that contrasts with that of Old World monkeys and may have been present in the founder generation on arrival in South America. In conclusion, there is a dichotomy within Xenarthra but otherwise the ancient South American mammals do not show much variation in principal placental characters. Thus, the successful radiation of these three groups, and their adaptation to diverse ecological niches, did not require substantial alterations in placentation. Copyright © 2013 Wiley Periodicals, Inc.

  5. Mid-Holocene to Present Climate Transition in Tropical South America

    Science.gov (United States)

    Turcq, B.; Cordeiro, R.; Sifeddine, A.; Braconnot, P.; Dias, P. S.; Costa, R.; Jorgetti, T.

    2008-12-01

    The classical illustration of Holocene climate changes in tropical South America is the huge rising of Titicaca lake level from 4400 to 4000 cal BP. Because the Amazon basin is the source of Andean rainfalls we have explored Amazonian data of climate changes during the Holocene to better understand the cause of this abrupt transition. Amazonian data confirm the existence of mid-Holocene dryness: (1) lacustrine level studies show a lower precipitation/evaporation budget than present, with the lowest lake levels between 8500 and 6800 cal BP; (2) although the dominant Holocene vegetation has always been the rainforest in the heart of Amazonia, this forest expanded towards the northwestern and southwestern regions from 6800 to 1550 cal BP, moreover, pioneer elements of the rainforest developed during the mid-Holocene and the best example is those of Cecropia, between 9000 and 5000 cal BP. (3) soil d13C indicates a forest expansion over savannas areas in Roraima (north), Mato Grosso and Rondonia (southwest), during the Holocene. (4) the mid-Holocene (8000- 4000 cal BP) is characterized by repeated occurrences of forest fires, marked by the presence of charcoals in soils and lacustrine sediments. However these different records are not characterized by abrupt transitions at the end of the Middle Holocene in Amazonia. In the Andean records there is a clear north-south shift in the timing of the transition. Analysis of coupled Ocean Atmosphere Model simulations suggest that convection in Amazon basin is directly controlled by insolation leading to an almost linear response of local climate to the global forcing. Differently, in the eastern and south-western regions where the rain is brought by the South American Monsoon, the climate transition appears more abrupt. It may be because the involved climate mechanisms are more complex and depend on Ocean/Atmosphere/Vegetation coupled process (ITCZ position, ZCAS formation, etc.). Tectonic movements or threshold links to

  6. Depositional Record of the Bagua Basin, Northern Peru: Implications for Climate and Tectonic Evolution of Tropical South America

    Science.gov (United States)

    Moreno, F.; George, S. W. M.; Williams, L. A.; Horton, B. K.; Garzione, C. N.

    2015-12-01

    The Andes Mountains exert critical controls on the climate, hydrology, and biodiversity of South America. The Bagua Basin, a low elevation (400-600 m) intermontane basin in northern Peru, offers a unique opportunity to study the ecological, climatic, and structural evolution of the western topographic boundary of the Amazonian foreland. Situated between the Marañon fold-thrust belt of the Western Cordillera and basement block uplifts of the Eastern Cordillera, the Bagua region contains a protracted, semi-continuous record of Triassic through Pleistocene sedimentation. Whereas Triassic-Cretaceous marine deposits were potentially related to extension and regional thermal subsidence, a Paleocene-Eocene shift to shallow marine and fluvial systems marks the onset of foreland basin conditions. Oligocene-Miocene sedimentation corresponds to a braided-meandering fluvial system with exceptional development of paleosols. In this study, we use new detrital zircon U-Pb geochronologic and oxygen stable isotopic datasets to establish a chronology of pre-Andean and Andean processes within the Bagua Basin. Detrital zircon geochronology provides constraints on when the Western and Eastern cordilleras shed sediments into the basin. Syndepositional zircons within Eocene, Oligocene and Miocene strata provide key age control for a previously poorly constrained depositional chronology. Preliminary results suggest a dramatic provenance shift in which Paleocene deposits contain almost exclusively cratonic populations (500-1600 Ma) whereas Eocene deposits show a mix of syndepositional zircons from the magmatic arc, recycled Mesozoic zircons, and cratonic zircon populations. Oxygen stable isotopes (δ18O) of carbonate nodules from Neogene paleosols will help elucidate when the Eastern Cordillera became an orographic barrier intercepting moisture from the Amazon basin to the east. Together, these records will help uncover the history of tectonics and climate interaction in tropical South

  7. Climate change and runoff in south-western Australia

    Science.gov (United States)

    Silberstein, R. P.; Aryal, S. K.; Durrant, J.; Pearcey, M.; Braccia, M.; Charles, S. P.; Boniecka, L.; Hodgson, G. A.; Bari, M. A.; Viney, N. R.; McFarlane, D. J.

    2012-12-01

    SummaryThis paper presents the results of computer simulations of runoff from 13 major fresh and brackish river basins in south-western Australia (SWA) under climate projections obtained from 15 GCMs with three future global warming scenarios equivalent to global temperature rises of 0.7 °C, 1.0 °C and 1.3 °C by 2030. The objective was to apply an efficient methodology, consistent across a large region, to examine the implications of the best available projections in climate trends for future surface water resources. An ensemble of rainfall-runoff models was calibrated on stream flow data from 1975 to 2007 from 106 gauged catchments distributed throughout the basins of the study area. The sensitivity of runoff to projected changes in mean annual rainfall is examined using the climate 'elasticity' concept. Averaged across the study area, all 15 GCMs project declines in rainfall under all global warming scenarios with a median decline of 8% resulting in a median decline in runoff of 25%. Such uniformity in projections from GCMs is unusual. Over SWA the average annual runoff under the 5th wettest and 5th driest of the 45 projections of the 2030 climate declines by 10 and 42%, respectively. Under the 5th driest projection the runoff decline ranges from 53% in the northern region to 40% in the southern region. Strong regional variations in climate sensitivity are found with the proportional decline in runoff greatest in the northern region and the greatest volumetric declines in the wetter basins in the south. Since the mid 1970s stream flows into the major water supply reservoirs in SWA have declined by more than 50% following a 16% rainfall reduction. This has already had major implications for water resources planning and for the preservation of aquatic and riparian ecosystems in the region. Our results indicate that this reduction in runoff is likely to continue if future climate projections eventuate.

  8. Projected future changes in vegetation in western North America in the 21st century

    Science.gov (United States)

    Xiaoyan, Jiang; Rauscher, Sara A.; Ringler, Todd D.; Lawrence, David M.; Williams, A. Park; Allen, Craig D.; Steiner, Allison L.; Cai, D. Michael; McDowell, Nate G.

    2013-01-01

    Rapid and broad-scale forest mortality associated with recent droughts, rising temperature, and insect outbreaks has been observed over western North America (NA). Climate models project additional future warming and increasing drought and water stress for this region. To assess future potential changes in vegetation distributions in western NA, the Community Earth System Model (CESM) coupled with its Dynamic Global Vegetation Model (DGVM) was used under the future A2 emissions scenario. To better span uncertainties in future climate, eight sea surface temperature (SST) projections provided by phase 3 of the Coupled Model Intercomparison Project (CMIP3) were employed as boundary conditions. There is a broad consensus among the simulations, despite differences in the simulated climate trajectories across the ensemble, that about half of the needleleaf evergreen tree coverage (from 24% to 11%) will disappear, coincident with a 14% (from 11% to 25%) increase in shrubs and grasses by the end of the twenty-first century in western NA, with most of the change occurring over the latter half of the twenty-first century. The net impact is a ~6 GtC or about 50% decrease in projected ecosystem carbon storage in this region. The findings suggest a potential for a widespread shift from tree-dominated landscapes to shrub and grass-dominated landscapes in western NA because of future warming and consequent increases in water deficits. These results highlight the need for improved process-based understanding of vegetation dynamics, particularly including mortality and the subsequent incorporation of these mechanisms into earth system models to better quantify the vulnerability of western NA forests under climate change.

  9. Two Millennia of Pb Pollution Related to Altiplano Metallurgical Activities and Leaded Gasoline in South America from Illimani Ice Core

    Science.gov (United States)

    Eichler, A.; Gramlich, G.; Kellerhals, T.; Tobler, L.; Schwikowski, M.

    2014-12-01

    The exploitation of the extended polymetallic deposits of the Altiplano in South America led to significant emissions of the neurotoxic Pb into the atmosphere already since pre-Colonial times. Long-term histories of Pb pollution in Eastern and Western Europe, Asia, and North America suggest that within the Northern Hemisphere emissions from metallurgy and coal combustion are minor compared to that from leaded gasoline during the second half of the 20th century. However, there is no equivalent data for Southern America. Here we present the first comprehensive, high-resolution two millennia Pb emission history for South America, based on an ice core record from Illimani glacier in Bolivia. Illimani is the highest mountain of the eastern Bolivian Andes and is located at the northeastern margin of the Bolivian Altiplano. The 2000 year ice-core based decadal Pb deposition history revealed highest Pb Enrichment Factors (EFs) during the period 1965-85. Metallurgical processing for silver production during periods of the Tiwanaku culture (400-900 AD), the Inca empire (1450-1532 AD), colonial times (1532-1900 AD), and the tin production at the beginning of the 20th century were identified as major sources for enhanced Pb EFs before the 1960s. Gasoline related Pb emissions in 1965-85, however, led to a threefold increase of the Pb EFs compared to the emission level from metal production, considerably preceding those of the past 2000 years. This finding is complementary to the local air pollution signal preserved in lake sediments and in good agreement with various studies from the Northern Hemisphere.

  10. Contingent Pacific-Atlantic Ocean influence on multicentury wildfire synchrony over western North America.

    Science.gov (United States)

    Kitzberger, Thomas; Brown, Peter M; Heyerdahl, Emily K; Swetnam, Thomas W; Veblen, Thomas T

    2007-01-09

    Widespread synchronous wildfires driven by climatic variation, such as those that swept western North America during 1996, 2000, and 2002, can result in major environmental and societal impacts. Understanding relationships between continental-scale patterns of drought and modes of sea surface temperatures (SSTs) such as El Niño-Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and Atlantic Multidecadal Oscillation (AMO) may explain how interannual to multidecadal variability in SSTs drives fire at continental scales. We used local wildfire chronologies reconstructed from fire scars on tree rings across western North America and independent reconstructions of SST developed from tree-ring widths at other sites to examine the relationships of multicentury patterns of climate and fire synchrony. From 33,039 annually resolved fire-scar dates at 238 sites (the largest paleofire record yet assembled), we examined forest fires at regional and subcontinental scales. Since 1550 CE, drought and forest fires covaried across the West, but in a manner contingent on SST modes. During certain phases of ENSO and PDO, fire was synchronous within broad subregions and sometimes asynchronous among those regions. In contrast, fires were most commonly synchronous across the West during warm phases of the AMO. ENSO and PDO were the main drivers of high-frequency variation in fire (interannual to decadal), whereas the AMO conditionally changed the strength and spatial influence of ENSO and PDO on wildfire occurrence at multidecadal scales. A current warming trend in AMO suggests that we may expect an increase in widespread, synchronous fires across the western U.S. in coming decades.

  11. An Evaluation of the Predictability of Austral Summer Season Precipitation over South America.

    Science.gov (United States)

    Misra, Vasubandhu

    2004-03-01

    In this study predictability of austral summer seasonal precipitation over South America is investigated using a 12-yr set of a 3.5-month range (seasonal) and a 17-yr range (continuous multiannual) five-member ensemble integrations of the Center for Ocean Land Atmosphere Studies (COLA) atmospheric general circulation model (AGCM). These integrations were performed with prescribed observed sea surface temperature (SST); therefore, skill attained represents an estimate of the upper bound of the skill achievable by COLA AGCM with predicted SST. The seasonal runs outperform the multiannual model integrations both in deterministic and probabilistic skill. The simulation of the January February March (JFM) seasonal climatology of precipitation is vastly superior in the seasonal runs except over the Nordeste region where the multiannual runs show a marginal improvement. The teleconnection of the ensemble mean JFM precipitation over tropical South America with global contemporaneous observed sea surface temperature in the seasonal runs conforms more closely to observations than in the multiannual runs. Both the sets of runs clearly beat persistence in predicting the interannual precipitation anomalies over the Amazon River basin, Nordeste, South Atlantic convergence zone, and subtropical South America. However, both types of runs display poorer simulations over subtropical regions than the tropical areas of South America. The examination of probabilistic skill of precipitation supports the conclusions from deterministic skill analysis that the seasonal runs yield superior simulations than the multiannual-type runs.

  12. South America and the proliferation of biological weapons

    OpenAIRE

    Tatiana Coutto

    2013-01-01

    This article focuses on the role of regional institutions and political practices in strengthening multilateral disarmament and non-proliferation regimes. Particular attention is devoted to coordination between Brazil and Argentina with a view to forging a "South American position" vis-à-vis the Biological and Toxins Weapons Convention (BTWC). Empirical evidence suggests that informal arrangements between the two countries were capable of involving other South American leaders and promoting t...

  13. Fire Ants (Solenopsis spp.) and Their Natural Enemies in Southern South America

    OpenAIRE

    Briano, Juan; Calcaterra, Luis; Varone, Laura

    2012-01-01

    We review the fire ant research conducted by the ARS-South American Biological Control Laboratory (SABCL) since 1987 to find a complex of natural enemies in southern South America and evaluate their specificity and suitability for field release as self-sustaining biological control agents. We also include those studies conducted by the ARS-Center for Medical, Agriculture, and Veterinary Entomology in the United States with the SABCL collaboration. Ecological and biological information is repo...

  14. Are diamond-bearing Cretaceous kimberlites related to shallow-angle subduction beneath western North America?

    Science.gov (United States)

    Currie, C. A.; Beaumont, C.

    2009-05-01

    The origin of deep-seated magmatism (in particular, kimberlites and lamproites) within continental plate interiors remains enigmatic in the context of plate tectonic theory. One hypothesis proposes a relationship between kimberlite occurrence and lithospheric subduction, such that a subducting plate releases fluids below a continental craton, triggering melting of the deep lithosphere and magmatism (Sharp, 1974; McCandless, 1999). This study provides a quantitative evaluation of this hypothesis, focusing on the Late Cretaceous- Eocene (105-50 Ma) kimberlites and lamproites of western North America. These magmas were emplaced along a corridor of Archean and Proterozoic lithosphere, 1000-1500 km inboard of the plate margin separating the subducting Farallon Plate and continental North America Plate. Kimberlite-lamproite magmatism coincides with tectonic events, including the Laramide orogeny, shut-down of the Sierra Nevada arc, and eastward migration of volcanism, that are commonly attributed to a change in Farallon Plate geometry to a shallow-angle trajectory (subduction that places the Farallon Plate beneath the western edge of the cratonic interior of North America. This geometry is consistent with the observed continental dynamic subsidence that lead to the development of the Western Interior Seaway. The models also show that the subducting plate has a cool thermal structure, and subducted hydrous minerals (serpentine, phengite and phlogopite) remain stable to more than 1200 km from the trench, where they may break down and release fluids that infiltrate the overlying craton lithosphere. This is supported by geochemical studies that indicate metasomatism of the Colorado Plateau and Wyoming craton mantle lithosphere by an aqueous fluid and/or silicate melt with a subduction signature. Through Cretaceous shallow-angle subduction, the Farallon Plate was in a position to mechanically and chemically interact with North American craton lithosphere at the time of

  15. Health outcomes among HIV-positive Latinos initiating antiretroviral therapy in North America versus Central and South America

    Science.gov (United States)

    Cesar, Carina; Koethe, John R; Giganti, Mark J; Rebeiro, Peter; Althoff, Keri N; Napravnik, Sonia; Mayor, Angel; Grinsztejn, Beatriz; Wolff, Marcelo; Padgett, Denis; Sierra-Madero, Juan; Gotuzzo, Eduardo; Sterling, Timothy R; Willig, James; Levison, Julie; Kitahata, Mari; Rodriguez-Barradas, Maria C; Moore, Richard D; McGowan, Catherine; Shepherd, Bryan E; Cahn, Pedro

    2016-01-01

    Introduction Latinos living with HIV in the Americas share a common ethnic and cultural heritage. In North America, Latinos have a relatively high rate of new HIV infections but lower rates of engagement at all stages of the care continuum, whereas in Latin America antiretroviral therapy (ART) services continue to expand to meet treatment needs. In this analysis, we compare HIV treatment outcomes between Latinos receiving ART in North America versus Latin America. Methods HIV-positive adults initiating ART at Caribbean, Central and South America Network for HIV (CCASAnet) sites were compared to Latino patients (based on country of origin or ethnic identity) starting treatment at North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) sites in the United States and Canada between 2000 and 2011. Cox proportional hazards models compared mortality, treatment interruption, antiretroviral regimen change, virologic failure and loss to follow-up between cohorts. Results The study included 8400 CCASAnet and 2786 NA-ACCORD patients initiating ART. CCASAnet patients were younger (median 35 vs. 37 years), more likely to be female (27% vs. 20%) and had lower nadir CD4 count (median 148 vs. 195 cells/µL, p<0.001 for all). In multivariable analyses, CCASAnet patients had a higher risk of mortality after ART initiation (adjusted hazard ratio (AHR) 1.61; 95% confidence interval (CI): 1.32 to 1.96), particularly during the first year, but a lower hazard of treatment interruption (AHR: 0.46; 95% CI: 0.42 to 0.50), change to second-line ART (AHR: 0.56; 95% CI: 0.51 to 0.62) and virologic failure (AHR: 0.52; 95% CI: 0.48 to 0.57). Conclusions HIV-positive Latinos initiating ART in Latin America have greater continuity of treatment but are at higher risk of death than Latinos in North America. Factors underlying these differences, such as HIV testing, linkage and access to care, warrant further investigation. PMID:26996992

  16. Satellite-Enhanced Regional Downscaling for Applied Studies: Extreme Precipitation Events in Southeastern South America

    Science.gov (United States)

    Nunes, A.; Gomes, G.; Ivanov, V. Y.

    2016-12-01

    Frequently found in southeastern South America during the warm season from October through May, strong and localized precipitation maxima are usually associated with the presence of mesoscale convective complexes (MCCs) travelling across the region. Flashfloods and landslides can be caused by these extremes in precipitation, with damages to the local communities. Heavily populated, southeastern South America hosts many agricultural activities and hydroelectric production. It encompasses one of the most important river basins in South America, the La Plata River Basin. Therefore, insufficient precipitation is equally prejudicial to the region socio-economic activities. MCCs are originated in the warm season of many regions of the world, however South American MCCs are related to the most severe thunderstorms, and have significantly contributed to the precipitation regime. We used the hourly outputs of Satellite-enhanced Regional Downscaling for Applied Studies (SRDAS), developed at the Federal University of Rio de Janeiro in Brazil, in the analysis of the dynamics and physical characteristics of MCCs in South America. SRDAS is the 25-km resolution downscaling of a global reanalysis available from January 1998 through December 2010. The Regional Spectral Model is the SRDAS atmospheric component and assimilates satellite-based precipitation estimates from the NOAA/Climate Prediction Center MORPHing technique global precipitation analyses. In this study, the SRDAS atmospheric and land-surface variables, global reanalysis products, infrared satellite imagery, and the physical retrievals from the Atmospheric Infrared Sounder (AIRS), on board of the NASA's Aqua satellite, were used in the evaluation of the MCCs developed in southeastern South America from 2008 and 2010. Low-level circulations and vertical profiles were analyzed together to establish the relevance of the moisture transport in connection with the upper-troposphere dynamics to the development of those MCCs.

  17. Molecular typing of canine distemper virus strains reveals the presence of a new genetic variant in South America.

    Science.gov (United States)

    Sarute, Nicolás; Pérez, Ruben; Aldaz, Jaime; Alfieri, Amauri A; Alfieri, Alice F; Name, Daniela; Llanes, Jessika; Hernández, Martín; Francia, Lourdes; Panzera, Yanina

    2014-06-01

    Canine distemper virus (CDV, Paramyxoviridae, Morbillivirus) is the causative agent of a severe infectious disease affecting terrestrial and marine carnivores worldwide. Phylogenetic relationships and the genetic variability of the hemagglutinin (H) protein and the fusion protein signal-peptide (Fsp) allow for the classification of field strains into genetic lineages. Currently, there are nine CDV lineages worldwide, two of them co-circulating in South America. Using the Fsp-coding region, we analyzed the genetic variability of strains from Uruguay, Brazil, and Ecuador, and compared them with those described previously in South America and other geographical areas. The results revealed that the Brazilian and Uruguayan strains belong to the already described South America lineage (EU1/SA1), whereas the Ecuadorian strains cluster in a new clade, here named South America 3, which may represent the third CDV lineage described in South America.

  18. Ice core based Pb pollution from gasoline in South America in the context of a 2000 year metallurgical history

    Science.gov (United States)

    Eichler, Anja; Gramlich, Gabriela; Kellerhals, Thomas; Tobler, Leonhard; Schwikowski, Margit

    2015-04-01

    Lead (Pb) is highly neurotoxic and, in contrast to many other heavy metals including cobalt, copper, and zinc, it has no beneficial effects to humans even at low concentrations. The introduction of leaded gasoline in the 1920s initiated a period of unabated growth in the global emissions of Pb. Prior to the onset of leaded gasoline phase-out in the 1970s, atmospheric Pb levels increased dramatically. Long-term histories of Pb pollution in Eastern and Western Europe, Asia, and North America suggest that emissions from leaded gasoline within the Northern Hemisphere are dominant compared to that from metallurgy and coal combustion during the second half of the 20th century. However, there is no equivalent data for Southern America. Although exploitation of the extensive polymetallic deposits of the Andean Altiplano in South America since pre-colonial times has caused substantial emissions of neurotoxic Pb into the atmosphere, its historical significance compared to recent Pb pollution from leaded gasoline is not yet resolved. Here we present the first comprehensive, high-resolution two millennia Pb emission history for South America, based on ice core records of Pb concentrations, Pb enrichment factors (EFs), and Pb isotope ratios from Illimani glacier in Bolivia. Complementary to local air pollution recorded in lake sediments, ice cores from mid latitude glaciers provide information about more extended source areas. Illimani is the highest mountain of the eastern Bolivian Andes and is located at the northeastern margin of the Bolivian Altiplano. The ice core Pb deposition history revealed enhanced Pb EFs due to metallurgical processing for silver production during periods of the Tiwanaku/Wari culture (AD 450-950), the Inca empires (AD 1450-1532), colonial times (AD 1532-1900), and tin production at the beginning of the 20th century. After the 1960s 208Pb/207Pb ratios decreased significantly, whereas Pb EFs increased by a factor of three compared to the emission level

  19. Plague bacterium as a transformer species in prairie dogs and the grasslands of western North America

    Science.gov (United States)

    Eads, David A.; Biggins, Dean E.

    2015-01-01

    Invasive transformer species change the character, condition, form, or nature of ecosystems and deserve considerable attention from conservation scientists. We applied the transformer species concept to the plague bacterium Yersinia pestis in western North America, where the pathogen was introduced around 1900. Y. pestis transforms grassland ecosystems by severely depleting the abundance of prairie dogs (Cynomys spp.) and thereby causing declines in native species abundance and diversity, including threatened and endangered species; altering food web connections; altering the import and export of nutrients; causing a loss of ecosystem resilience to encroaching invasive plants; and modifying prairie dog burrows. Y. pestis poses an important challenge to conservation biologists because it causes trophic-level perturbations that affect the stability of ecosystems. Unfortunately, understanding of the effects of Y. pestis on ecosystems is rudimentary, highlighting an acute need for continued research.

  20. Alpine treeline of western North America: Linking organism-to-landscape dynamics

    Science.gov (United States)

    Malanson, George P.; Butler, David R.; Fagre, Daniel B.; Walsh, Stephen J; Tomback, Diana F.; Daniels, Lori D.; Resler, Lynn M.; Smith, William K.; Weiss, Daniel J.; Peterson, David L.; Bunn, Andrew G.; Hiemstra, Christopher A.; Liptzin, Daniel; Bourgeron, Patrick S.; Shen, Zehao; Millar, Constance I.

    2007-01-01

    Although the ecological dynamics of the alpine treeline ecotone are influenced by climate, it is an imperfect indicator of climate change. Mechanistic processes that shape the ecotone—seed rain, seed germination, seedling establishment and subsequent tree growth form, or, conversely tree dieback—depend on microsite patterns. Growth forms affect wind and snow, and so develop positive and negative feedback loops that create these microsites. As a result, complex landscape patterns are generated at multiple spatial scales. Although these mechanistic processes are fundamentally the same for all forest-tundra ecotones across western North America, factors such as prior climate, underlying geology and geomorphology, and genetic constraints of dominant tree species lead to geographic differences in the responses of particular ecotones to climate change.

  1. Anatexis and metamorphism in tectonically thickened continental crust exemplified by the Sevier hinterland, western North America

    Science.gov (United States)

    Patino Douce, Alberto E.; Humphreys, Eugene D.; Johnston, A. Dana

    1990-01-01

    This paper presents a thermal and petrologic model of anatexis and metamorphism in regions of crustal thickening exemplified by the Sevier hinterland in western North America, and uses the model to examine the geological and physical processes leading to crustally derived magmatism. The results of numerical experiments show that anatexis was an inevitable end-product of Barrovian metamorphism in the thickened crust of the late Mesozoic Sevier orogenic belt and that the advection of heat across the lithosphere, in the form of mantle-derived mafic magmas, was not required for melting of metasedimentary rocks. It is suggested that, in the Sevier belt, as in other intracontinental orogenic belts, anatexis occurred in the midcrust and not at the base of the crust.

  2. Plague bacterium as a transformer species in prairie dogs and the grasslands of western North America.

    Science.gov (United States)

    Eads, David A; Biggins, Dean E

    2015-08-01

    Invasive transformer species change the character, condition, form, or nature of ecosystems and deserve considerable attention from conservation scientists. We applied the transformer species concept to the plague bacterium Yersinia pestis in western North America, where the pathogen was introduced around 1900. Y. pestis transforms grassland ecosystems by severely depleting the abundance of prairie dogs (Cynomys spp.) and thereby causing declines in native species abundance and diversity, including threatened and endangered species; altering food web connections; altering the import and export of nutrients; causing a loss of ecosystem resilience to encroaching invasive plants; and modifying prairie dog burrows. Y. pestis poses an important challenge to conservation biologists because it causes trophic-level perturbations that affect the stability of ecosystems. Unfortunately, understanding of the effects of Y. pestis on ecosystems is rudimentary, highlighting an acute need for continued research. © 2015 Society for Conservation Biology.

  3. Position paper: Inland waterways classification for South America : Core concepts and initial proposals

    NARCIS (Netherlands)

    Jaimurzina, A.; Koedijk, O.C.; Wilmsmeier, G.; Dohms, A.; Montiel, D.; Pauli, G.; Rigo, P; Spengler, T.; Wens, F.

    2016-01-01

    South America, as of yet, has not been able to take full advantage of its extensive system of naturally navigable waterways and in making them an integrated part of the region’s transport network to cater for the ever increasing demand for cargo and human mobility. Infrastructure limitations are one

  4. Characterizing Temperature Variability and Associated Large Scale Meteorological Patterns Across South America

    Science.gov (United States)

    Detzer, J.; Loikith, P. C.; Mechoso, C. R.; Barkhordarian, A.; Lee, H.

    2017-12-01

    South America's climate varies considerably owing to its large geographic range and diverse topographical features. Spanning the tropics to the mid-latitudes and from high peaks to tropical rainforest, the continent experiences an array of climate and weather patterns. Due to this considerable spatial extent, assessing temperature variability at the continent scale is particularly challenging. It is well documented in the literature that temperatures have been increasing across portions of South America in recent decades, and while there have been many studies that have focused on precipitation variability and change, temperature has received less scientific attention. Therefore, a more thorough understanding of the drivers of temperature variability is critical for interpreting future change. First, k-means cluster analysis is used to identify four primary modes of temperature variability across the continent, stratified by season. Next, composites of large scale meteorological patterns (LSMPs) are calculated for months assigned to each cluster. Initial results suggest that LSMPs, defined using meteorological variables such as sea level pressure (SLP), geopotential height, and wind, are able to identify synoptic scale mechanisms important for driving temperature variability at the monthly scale. Some LSMPs indicate a relationship with known recurrent modes of climate variability. For example, composites of geopotential height suggest that the Southern Annular Mode is an important, but not necessarily dominant, component of temperature variability over southern South America. This work will be extended to assess the drivers of temperature extremes across South America.

  5. Migration of Computer Science Graduates from South Asia to Europe and North America

    Science.gov (United States)

    Khan, W. A.; Siddiqi, A. B.; Ahmed, F.

    2006-01-01

    This paper addresses the influx of computer science graduates from South Asia into Europe and North America. It analyses the need and supply chains between two points and identifies the pros and cons of the education imparted to these graduates. The effects of social disorder due to migrations are addressed. The resulting technological vacuum in…

  6. Conserving the grassland Important Bird Areas (IBAs) of southern South America: Argentina, Uruguay, Paraguay, and Brazil

    Science.gov (United States)

    Adrian S. Di Giacomo; Santiago Krapovickas

    2005-01-01

    In the southern part of South America, knowledge about bird species distribution is still not used as a tool for land use planning and conservation priority-setting. BirdLife International’s Important Bird Areas (IBA) Program is an appropriate vehicle for analyzing existing information about birds, and to generate new data where necessary. IBA inventories...

  7. Overseas Educational Developments, 1981: Mexico, South America, Southeast Asia. A World Higher Education Communique Special Report.

    Science.gov (United States)

    Institute of International Education, New York, NY.

    Educational developments in Mexico, South America, and Southeast Asia are covered in five seminar papers. In addition, country educational profiles are presented on Mexico, Hong Kong, Malaysia, the Philippines, Singapore, Thailand, and Indonesia. In "International Students from Southeast Asia," John F. Brohm considers the following…

  8. Gilles de la Tourette Syndrome—A Case Report from Guyana in South America

    Directory of Open Access Journals (Sweden)

    V. Eapen

    1992-01-01

    Full Text Available A case of the Gilles de la Tourette syndrome from Guyana in South America is presented. The patient had a positive family history as well as coprolalia, echolalia, and attention deficit disorder with hyperactivity. The family history and cross-cultural similarity emphasise the biological factors in the aetiology of the syndrome.

  9. Book review: Vetter, H. 2005. Terralog. Turtles of the World. Vol. 3. Central and South America

    Directory of Open Access Journals (Sweden)

    2006-12-01

    Full Text Available Book review: Vetter, H. 2005. Terralog. Turtles of the World. Vol. 3. Central and South America/Schildkröten der Welt Band 3. Mittel- und Südamerika: 1-128, color pictures 606 + 9. Edition Chimaira, Frankfurt, Germany.ISBN 3-930612-82-8; 29.7 x 20.8 cm

  10. Parallel diversifications of Cremastosperma and Mosannona (Annonaceae), tropical rainforest trees tracking Neogene upheaval of South America

    NARCIS (Netherlands)

    Pirie, M.D.; Maas, P.J.M.; Wilschut, R.A.; Melchers-Sharrott, H.; Chatrou, L.W.

    2018-01-01

    Much of the immense present day biological diversity of Neotropical rainforests originated from the Miocene onwards, a period of geological and ecological upheaval in South America. We assess the impact of the Andean orogeny, drainage of Lake Pebas and closure of the Panama isthmus on two clades of

  11. Parallel diversifications of Cremastosperma and mosannona (annonaceae), tropical rainforest trees tracking neogene upheaval of South America

    NARCIS (Netherlands)

    Pirie, Michael D.; Maas, Paul J.M.; Wilschut, Rutger A.; Melchers-Sharrott, Heleen; Chatrou, Lars W.

    2018-01-01

    Much of the immense present day biological diversity of Neotropical rainforests originated from the Miocene onwards, a period of geological and ecological upheaval in South America. We assess the impact of the Andean orogeny, drainage of Lake Pebas and closure of the Panama isthmus on two clades of

  12. Land use change and ecosystem service provision in Pampas and Campos grasslands of southern South America

    NARCIS (Netherlands)

    Modernel Hristoff, Pablo; Rossing, W.A.H.; Corbeels, M.; Dogliotti, S.; Picasso, V.; Tittonell, P.

    2016-01-01

    New livestock production models need to simultaneously meet the increasing global demand for meat and preserve biodiversity and ecosystem services. Since the 16th century beef cattle has been produced on the Pampas and Campos native grasslands in southern South America, with only small amounts of

  13. Long-term trends and interannual variability of forest, savanna and agricultural fires in South America

    NARCIS (Netherlands)

    Chen, Y.; Morton, D. C.; Yin, Y. F.; Collatz, G. J.; Kasibhatla, P. S.; van der Werf, G.R.; DeFries, R. S.; Randerson, J. T.

    2013-01-01

    Background: Landscape fires in South America have considerable impacts on ecosystems, air quality and the climate system. We examined long-term trends and interannual variability of forest, savanna and agricultural fires for the continent during 2001-2012 using multiple satellite-derived fire

  14. Multilocus genotypes indicate differentiation among Puccinia psidii populations from South America and Hawaii

    Science.gov (United States)

    R. N. Graca; A. C. Alfenas; A. L. Ross-Davis; Ned Klopfenstein; M. -S. Kim; T. L. Peever; P. G. Cannon; J. Y. Uchida; C. Y. Kadooka; R. D. Hauff

    2011-01-01

    Puccinia psidii is the cause of rust disease of many host species in the Myrtaceae family, including guava (Psidium spp.), eucalypt (Eucalyptus spp.), rose apple (Syzygium jambos), and 'ohi'a (Metrosideros polymorpha). First reported in 1884 on guava in Brazil, the rust has since been detected in South America (Argentina, Brazil, Colombia, Paraguay, Uruguay,...

  15. The sexual history of the global South: sexual politics in Africa, Asia and Latin America

    NARCIS (Netherlands)

    Wieringa, S.; Sívori, H.

    2013-01-01

    The Sexual History of the Global South explores the gap between sexuality studies and post-colonial cultural critique. Featuring twelve case studies, based on original historical and ethnographic research from countries in Africa, Asia, and Latin America, the book examines the sexual investments

  16. Spatiotemporal patterns of mercury accumulation in lake sediments of western North America

    Science.gov (United States)

    Drevnick, Paul; Cooke, Colin A.; Barraza, Daniella; Blais, Jules M.; Coale, Kenneth; Cumming, Brian F.; Curtis, Chris; Das, Biplob; Donahue, William F.; Eagles-Smith, Collin A.; Engstrom, Daniel R.; Fitzgerald, William F.; Furl, Chad V.; Gray, John R.; Hall, Roland I.; Jackson, Togwell A.; Laird, Kathleen R.; Lockhart, W. Lyle; Macdonald, Robie W.; Mast, M. Alisa; Mathieu, Callie; Muir, Derek C.G.; Outridge, Peter; Reinemann, Scott; Rothenberg, Sarah E.; Ruiz-Fernandex, Ana Carolina; St. Louis, V.L.; Sanders, Rhea; Sanei, Hamed; Skierszkan, Elliott; Van Metre, Peter C.; Veverica, Timothy; Wiklund, Johan A.; Wolfe, Brent B.

    2016-01-01

    For the Western North America Mercury Synthesis, we compiled mercury records from 165 dated sediment cores from 138 natural lakes across western North America. Lake sediments are accepted as faithful recorders of historical mercury accumulation rates, and regional and sub-regional temporal and spatial trends were analyzed with descriptive and inferential statistics. Mercury accumulation rates in sediments have increased, on average, four times (4×) from 1850 to 2000 and continue to increase by approximately 0.2 μg/m2 per year. Lakes with the greatest increases were influenced by the Flin Flon smelter, followed by lakes directly affected by mining and wastewater discharges. Of lakes not directly affected by point sources, there is a clear separation in mercury accumulation rates between lakes with no/little watershed development and lakes with extensive watershed development for agricultural and/or residential purposes. Lakes in the latter group exhibited a sharp increase in mercury accumulation rates with human settlement, stabilizing after 1950 at five times (5×) 1850 rates. Mercury accumulation rates in lakes with no/little watershed development were controlled primarily by relative watershed size prior to 1850, and since have exhibited modest increases (in absolute terms and compared to that described above) associated with (regional and global) industrialization. A sub-regional analysis highlighted that in the ecoregion Northwestern Forest Mountains, mercury deposited to watersheds is delivered to lakes. Research is warranted to understand whether mountainous watersheds act as permanent sinks for mercury or if export of “legacy” mercury (deposited in years past) will delay recovery when/if emissions reductions are achieved.

  17. Hg concentrations in fish from coastal waters of California and Western North America

    Science.gov (United States)

    Davis, Jay; Ross, John; Bezalel, Shira; Sim, Lawrence; Bonnema, Autumn; Ichikawa, Gary; Heim, Wes; Schiff, Kenneth C; Eagles-Smith, Collin A.; Ackerman, Joshua T.

    2016-01-01

    The State of California conducted an extensive and systematic survey of mercury (Hg) in fish from the California coast in 2009 and 2010. The California survey sampled 3483 fish representing 46 species at 68 locations, and demonstrated that methylHg in fish presents a widespread exposure risk to fish consumers. Most of the locations sampled (37 of 68) had a species with an average concentration above 0.3 μg/g wet weight (ww), and 10 locations an average above 1.0 μg/g ww. The recent and robust dataset from California provided a basis for a broader examination of spatial and temporal patterns in fish Hg in coastal waters of Western North America. There is a striking lack of data in publicly accessible databases on Hg and other contaminants in coastal fish. An assessment of the raw data from these databases suggested the presence of relatively high concentrations along the California coast and in Puget Sound, and relatively low concentrations along the coasts of Alaska and Oregon, and the outer coast of Washington. The dataset suggests that Hg concentrations of public health concern can be observed at any location on the coast of Western North America where long-lived predator species are sampled. Output from a linear mixed-effects model resembled the spatial pattern observed for the raw data and suggested, based on the limited dataset, a lack of trend in fish Hg over the nearly 30-year period covered by the dataset. Expanded and continued monitoring, accompanied by rigorous data management procedures, would be of great value in characterizing methylHg exposure, and tracking changes in contamination of coastal fish in response to possible increases in atmospheric Hg emissions in Asia, climate change, and terrestrial Hg control efforts in coastal watersheds.

  18. Patterns of species richness in sandy beaches of South America ...

    African Journals Online (AJOL)

    The middle shore is primarily occupied by cirolanids and bivalves, and hippid crabs, bivalves and amphipods dominate the lower beach. Generally, species richness increases from upper to lower beach levels. Studies carried out on exposed sandy beaches of south-central Chile (ca. 40°S) show that different beach states ...

  19. The Utilization of Historical Data and Geospatial Technology Advances at the Jornada Experimental Range to Support Western America Ranching Culture

    Directory of Open Access Journals (Sweden)

    Kris Havstad

    2011-09-01

    Full Text Available By the early 1900s, concerns were expressed by ranchers, academicians, and federal scientists that widespread overgrazing and invasion of native grassland by woody shrubs were having severe negative impacts upon normal grazing practices in Western America. Ranchers wanted to reverse these trends and continue their way of life and were willing to work with scientists to achieve these goals. One response to this desire was establishment of the USDA Jornada Experimental Range (783 km2 in south central New Mexico by a Presidential Executive Order in 1912 for conducting rangeland investigations. This cooperative effort involved experiments to understand principles of proper management and the processes causing the woody shrub invasion as well as to identify treatments to eradicate shrubs. By the late 1940s, it was apparent that combining the historical ground-based data accumulated at Jornada Experimental Range with rapidly expanding post World War II technologies would yield a better understanding of the driving processes in these arid and semiarid ecosystems which could then lead to improved rangeland management practices. One specific technology was the use of aerial photography to interpret landscape resource conditions. The assembly and utilization of long-term historical aerial photography data sets has occurred over the last half century. More recently, Global Positioning System (GPS techniques have been used in a myriad of scientific endeavors including efforts to accurately locate historical and contemporary treatment plots and to track research animals including livestock and wildlife. As an incredible amount of both spatial and temporal data became available, Geographic Information Systems have been exploited to display various layers of data over the same locations. Subsequent analyses of these data layers have begun to yield new insights. The most recent technological development has been the deployment of Unmanned Aerial Vehicles (UAVs

  20. Spatial Analysis of the Effects of the Anomalous Winter of 2014/15 on 157 Ski Resorts Located in Western North America

    Science.gov (United States)

    Bahbahani, K. M.; Pidwirny, M. J.

    2017-12-01

    The winter of 2014/2015 was one of the warmest in recent history for many locations in western North America. The cause of this climate irregularity was the development of extremely warm ocean surface waters (The Blob) over much of the eastern North Pacific Ocean. During this winter season, many ski resorts in western Canada and the United States either did not open or were forced to close their ski season early. Here, we examine climate data from 157 ski resorts to develop a picture of where the effected locations were in western North America. Using the climate database software ClimateBC and ClimateNA, high quality downscaled historical data was generated for the winter season (December, January, and February) for the variables mean temperature, snowfall, and rainfall. Values for winter of 2014/15 were statistically compared to the 30-year normal period from 1981-2010. Z-scores were calculated for 2014/15 relative to the selected 30-year normal period. These Z-score values were then mapped using ArcGIS. From the mean winter temperature map, it is apparent that abnormally warm temperatures influenced many ski resorts in California, Nevada, western Oregon, Washington, Arizona, Utah, southern Idaho, and parts of southern British Columbia. The winter snowfall map shows anomalous below normal conditions only at two resorts in south-central British Columbia and a single above normal situation at one site in central Colorado. The winter rainfall map displays that many ski resorts in New Mexico, Arizona, southern Utah, Colorado, Wyoming, Montana, Idaho, western Washington, and southwestern British Columbia experienced exceptional above normal winter season rainfalls. It is highly likely that the next Blob will be forecasted many months in advance of its occurrence. The results of this study have identified which ski resorts could be climatically influenced by such an event. This information may help reduce potential financial losses to ski resorts and their associated

  1. Radiotherapy in the Barwon South Western Region: a rural perspective

    International Nuclear Information System (INIS)

    Henry, Margaret J.; Jones, Phil; Coory Michael; Chapman, Adam; Morrissy, Kate; Matheson, Leigh M.; Pitson, Graham; Lynch, Rod; Healy, Pat; Ashley, David

    2014-01-01

    Cancer-related mortality rates are higher in rural areas compared with urban regions. Whether there are corresponding geographical variations in radiotherapy utilisation rates (RURs) is the subject of this study. RURs for the regional centre of Geelong and rural areas of the Barwon South Western Region were calculated using a population-based database (2009). Lower RURs were observed for rural patients compared with the Geelong region for prostate cancer (15.7% vs 25.8%, P=0.02), rectal cancer (32.8% vs 44.7%, P=0.11), lymphoma (9.4% vs 26.2%, P=0.05), and all cancers overall (25.6% vs 28.9%, P=0.06). This lower rate was significant in men (rural, 19.9%; Geelong, 28.3%; P=0.00) but not in women (rural, 33.6%; Geelong, 29.7%; P=0.88). Time from diagnosis to radiotherapy was not significantly different for patients from the two regions. Tumour staging within the rural and Geelong regions was not significantly different for the major tumour streams of rectal, prostate and lung cancer (P=0.61, P=0.79, P=0.43, respectively). A higher proportion of tumours were unstaged or unstageable in the rural region for lung (44% vs 18%, P<0.01) and prostate (73% vs 57%, P<0.01) cancer. Lower RURs were observed in our rural region. Differences found within tumour streams and in men suggest a complexity of relationships that will require further study.

  2. Hybrid warfare of the USA in South America

    Directory of Open Access Journals (Sweden)

    A. V. Budaev

    2015-01-01

    Full Text Available Washington’s hybrid warfare in Latin American region differs by its inventive and sophisticated methods and in fact represents a complex and multidimensional phenomenon including symbiosis of the “soft” and “hard” power as well as their combination in the form of the “smart power”. The increasing importance of hybrid warfare technologies in the US foreign policy in Latin America predetermines the necessity of thorough studies and analysis of this phenomenon for providing Russian interests.

  3. Four decades of water recycling in Atlantis (Western Cape, South Africa): Past, present and future

    CSIR Research Space (South Africa)

    Bugan, Richard DH

    2016-10-01

    Full Text Available The primary aquifer at Atlantis (Western Cape, South Africa) is ideally suited for water supply and the indirect recycling of urban stormwater runoff and treated domestic wastewater for potable purposes. The relatively thin, sloping aquifer requires...

  4. [Power and health in South America: international sanitary conferences, 1870-1889].

    Science.gov (United States)

    Chaves, Cleide de Lima

    2013-06-01

    This article analyzes the international sanitary conferences that were held in South America in 1873 and 1887, involving the Brazilian Empire and the Republics of Argentina and Uruguay, as an integral part of a series of similar events that took place in Europe and North America starting in the second half of the nineteenth century. The interests of the countries involved, namely trade relations and immigration from Europe - both directly affected by the epidemics - are discussed, and the repercussions of these sanitary agreements on the other countries in the Americas are indicated. The American health conventions in the late nineteenth century represented the first initiatives in the Americas to solve international public health problems.

  5. South America and the proliferation of biological weapons

    Directory of Open Access Journals (Sweden)

    Tatiana Coutto

    2013-04-01

    Full Text Available This article focuses on the role of regional institutions and political practices in strengthening multilateral disarmament and non-proliferation regimes. Particular attention is devoted to coordination between Brazil and Argentina with a view to forging a "South American position" vis-à-vis the Biological and Toxins Weapons Convention (BTWC. Empirical evidence suggests that informal arrangements between the two countries were capable of involving other South American leaders and promoting the exchange of information among different groups of states, most notably during the 2006 BTWC review conference. This paper also sheds light on the identification of specific features that allow for increasing visibility and actorness of regional powers in promoting universality of multilateral security regimes (MSR, as well as the limitations faced by these players.

  6. Taxonomic review of the species of Mugil (Teleostei: Perciformes: Mugilidae) from the Atlantic South Caribbean and South America, with integration of morphological, cytogenetic and molecular data.

    Science.gov (United States)

    Menezes, Naércio A; Nirchio, Mauro; De Oliveira, Cláudio; Siccharamirez, Raquel

    2015-01-10

    Analysis of morphological, molecular and cytological data helped to define and more precisely characterize the species of Mugil from the Atlantic coasts of South Caribbean and South America, allowing a correction of prior misidentifications and distributional ranges. A new species from Venezuela is described and all the species from the area are redescribed. It is demonstrated that the apparent similarity in morphological traits, which contradicted the results from recent molecular studies, is the result of the misuse of traditional morphological characters, and thus both the molecular and cytological data instead are congruent with the morphological differences that are found among mullet species. The presence of Mugil hospes Jordan & Culver in the western south Atlantic is refuted based on the comparison of type material of this species with specimens from this area that also indicated a very significant morphological difference, what on the other hand justifies the recognition of these specimens as Mugil brevirostris (Ribeiro). The distribution of Mugil incilis Hancock is restricted and the similarities among the species formerly depicted in a prior dendrogram is modified following the inclusion of recently obtained molecular data for Mugil curvidens Valenciennes.

  7. Governance, agricultural intensification, and land sparing in tropical South America

    OpenAIRE

    CEDDIA Michele Graziano; BARDSLEY N. O.; GOMEZ Y PALOMA Sergio; SEDLACEK S

    2014-01-01

    In this paper we address two topical questions: How do the quality of governance and agricultural intensification impact on spatial expansion of agriculture? Which aspects of governance are more likely to ensure that agricultural intensification allows sparing land for nature? Using data from the Food and Agriculture Organization, the World Bank, the World Database on Protected Areas, and the Yale Center for Environmental Law and Policy, we estimate a panel data model for six South A...

  8. Patterns of species richness in sandy beaches of South America

    African Journals Online (AJOL)

    beaches with rdkctive and dissip:1tive characteristics (sensu. R eprodu ced by Sabin et G atew ay u n der licen ce gran ted by th e P u blish er (dated 2009). ... beach intertidal communities WaS reviewed, (b) location of len sam.!y beaches studied in south-central Chile, imd (c) location of two sandy beaches studied on the ...

  9. Phylogeography and spatial structure of the lowland tapir (Tapirus terrestris, Perissodactyla: Tapiridae) in South America.

    Science.gov (United States)

    Ruiz-García, Manuel; Vásquez, Catalina; Sandoval, Sergio; Kaston, Franz; Luengas-Villamil, Kelly; Shostell, Joseph Mark

    2016-07-01

    We sequenced the mitochondrial cytochrome b gene of 141 lowland tapirs (Tapirus terrestris) - representing the largest geographical distribution sample of this species studied across of South America to date. We compare our new data regard to two previous works on population structure and molecular systematics of T. terrestris. Our data agree with the Thoisy et al.'s work in (1) the Northern Western Amazon basin was the area with the highest gene diversity levels in T. terrestris, being probably the area of initial diversification; (2) there was no clear association between haplogroups and specific geographical areas; (3) there were clear population decreases during the last glacial maximum for the different haplogroups detected, followed by population expansions during the Holocene; and (4) our temporal splits among different T. terrestris haplogroups coincided with the first molecular clock approach carried out by these authors (fossil calibration). Nevertheless, our study disagreed regard to other aspects of the Thoisy et al.'s claims: (1) meanwhile, they detected four relevant clades in their data, we put forward six different relevant clades; (2) the Amazon River was not a strong barrier for haplotype dispersion in T. terrestris; and (3) we found reciprocal monophyly between T. terrestris and T. pinchaque. Additionally, we sequenced 42 individuals (T. terrestris, T. pinchaque, T. bairdii, and the alleged "new species", T. kabomani) for three concatenated mitochondrial genes (Cyt-b, COI, and COII) agreeing quite well with the view of Voss et al., and against of the claims of Cozzuol et al. Tapirus kabomani should be not considered as a full species with the results obtained throughout the mitochondrial sequences.

  10. Mechanism of climate change over South America during the LGM in coupled Ocean- Atmosphere model simulations

    Science.gov (United States)

    Khodri, M.

    2006-12-01

    On a regional perspective the database of proxy information for South America during the Last Glacial Maximum (LGM) shows large and regionally extensive changes of the mean climate and vegetation types over the Amazon basin. In some instances these changes were associated with decrease in the mean precipitation amount (and most probably in moist deep convection) over the Amazonian and South East Brazil monsoon regions and wetter mean conditions in present day drought-prone regions such as Northeast of Brazil (Nordeste). These changes have been interpreted as local responses to shift in the mean position and intensity of the Atlantic ITCZ due to glacial extratropical forcings or to changes in the South American Monsoons. However there are still two issues is the path to further understand the mechanism of climate change over South America during the LGM. The first is incomplete knowledge in both the modeling and observational communities of how the moist deep convection over the Amazonian region respond to glacial boundary condition and how this changes might interact with the meridional shift of rainfall over Nordeste and Atlantic Ocean. The second is our understanding of how ocean-atmosphere changes that do occur in the tropical Pacific region influence the climate of the remainder of the planet and on a regional way over South America. Using PMIP-2 coupled Ocean-Atmosphere simulations for LGM and comparison to paleodata we show that hydrological cycle changes over the Amazon basin might be independent of their Atlantic Ocean counterpart, while teleconnections with Pacific Ocean might have played a significant role in the observed changes over tropical South America.

  11. Current status, distribution, and conservation of the Burrowing Owl (Speotyto cunicularia) in midwestern and western North America

    Science.gov (United States)

    Steven R. Sheffield

    1997-01-01

    The Burrowing Owl (Speotyto cunicularia) inhabits open prairie grassland habitat in the midwestern and western US and Canada. For several years now, numbers of this species in North America have been declining at an alarming rate. Currently, Burrowing Owls are listed as endangered in Canada and threatened in Mexico. In the United States, the...

  12. Cryptolepiota, a new sequestrate genus in the Agaricaceae with evidence for adaptive radiation in western North America

    Science.gov (United States)

    Bradley R. Kropp; Steve Albee-Scott; Michael A. Castellano; James M. Trappe

    2012-01-01

    Phylogenetic analyses based on nLSU and ITS sequence data indicate that the sequestrate genus Gigasperma is polyphyletic. Gigasperma cryptica, which is known only from New Zealand, has affinities with the Cortinariaceae whereas G. americanum and two additional undescribed taxa from western North America are...

  13. Strategies, tools, and challenges for sustaining and restoring high elevation five-needle white pine forests in western North America

    Science.gov (United States)

    Robert E. Keane; Anna W. Schoettle

    2011-01-01

    Many ecologically important, five-needle white pine forests that historically dominated the high elevation landscapes of western North America are now being heavily impacted by mountain pine beetle (Dendroctonus spp.) outbreaks, the exotic disease white pine blister rust (WPBR), and altered high elevation fire regimes. Management intervention using specially designed...

  14. Influence of forest and rangeland management on anadromous fish habitat in Western North America: water transportation and storage of logs.

    Science.gov (United States)

    J.R. Sedell; W.S. Duval

    1985-01-01

    Environmental effects of water transportation of logs in western North America include the historical driving of logs in rivers and streams, and the current dumping, sorting, transportation, and storage of logs in rivers and estuaries in British Columbia and southeastern Alaska. The historical discussion focuses on habitat losses and volumes of...

  15. Acculturation Strategies Among South Asian Immigrants: The Mediators of Atherosclerosis in South Asians Living in America (MASALA) Study.

    Science.gov (United States)

    Needham, Belinda L; Mukherjee, Bhramar; Bagchi, Pramita; Kim, Catherine; Mukherjea, Arnab; Kandula, Namratha R; Kanaya, Alka M

    2017-04-01

    In the past, epidemiologic research on acculturation and health has been criticized for its conceptual ambiguity and simplistic measurement approaches. This study applied a widely-used theoretical framework from cross-cultural psychology to identify acculturation strategies among South Asian immigrants in the US and to examine sociodemographic correlates of acculturation strategies. Data were from the Mediators of Atherosclerosis in South Asians Living in America study. We used latent class analysis to identify groups of individuals that were similar based on cultural attitudes and behaviors. We used latent class regression analysis to examine sociodemographic correlates of acculturation strategies. We found that South Asian immigrants employed three acculturation strategies, including separation (characterized by a relatively high degree of preference for South Asian culture over US culture), assimilation (characterized by a relatively high degree of preference for US culture over South Asian culture), and integration (characterized by a similar level of preference for South Asian and US cultures). Respondents with no religious affiliation, those with higher levels of income, those who lived a greater percentage of their lives in the US, and those who spoke English well or very well were less likely to use the separation strategy than the assimilation or integration strategies. Using epidemiologic cohort data, this study illustrated a conceptual and methodological approach that addresses limitations of previous research on acculturation and health. More work is needed to understand how the acculturation strategies identified in this study affect the health of South Asian immigrants in the US.

  16. Paleosecular Type Curves for South America Based on Holocene-Pleistocene Lake Sediments Studies

    Science.gov (United States)

    Gogorza, C. S.

    2007-05-01

    Most of the high-resolution paleomagnetic secular variation (PSV) results were obtained from records on sediments from the Northern Hemisphere. Experimental results from South America are scarce. The first results were obtained by Creer et al. (1983) and have been continued since few years ago by the author and collaborators. This review deals with studies of PSV records from bottom sediments from three lakes: Escondido, Moreno and El Trébol (south-western Argentina, 41° S, 71° 30'W). Measurements of directions (declination D and inclination I) and intensity of natural remanent magnetization (NRM), magnetic susceptibility at low and high frequency (specific, X and volumetric, k), isothermal remanent magnetization (IRM), saturation isothermal remanent magnetization (SIRM), and back field were carried out. Stability of the NRM was investigated by alternating-field demagnetization. Rock magnetic studies suggest that the main carriers of magnetization are ferrimagnetic minerals, predominantly pseudo single domain magnetite. The correlation between cores was based on magnetic parameters as X and NRM. The tephra layers were identified from the lithologic profiles and also from the magnetic susceptibility logs. Due to their different chronological meaning and their rather bad behavior as magnetic recorder, these layers were removed from the sequence and the gaps that were produced along the profiles by the removal were closed, obtaining a "shortened depth". Radiocarbon age estimates from these cores and from earlier studies allow us to construct paleosecular variation records for the past 22,000 years. Inclination and declination curves (Gogorza et al., 2000a; Gogorza et al., 2002; Irurzun et al., 2006) show trends that are similar to a paleomagnetic secular variation curve for SW of Argentina (Gogorza et al., 2000b). References Creer, K.M., Tucholka, P. and Barton, C.E. 1983. Paleomagnetism of lake sediments, in Geomagnetism of Baked Clays and Recent Sediments, edited

  17. CYP1A1 Genetic Polymorphisms in Ecuador, South America

    Directory of Open Access Journals (Sweden)

    César Paz-y-Miño

    2005-01-01

    Full Text Available A total of 108 individuals from the Ecuadorian population from rural and urban places were analyzed for two CYP1A1 gene polymorphisms. The frequency of the val allele at codon 462 was 0.50, while the frequency of the Msp I restriction site, m2 allele at the T6235C position was 0.70. These polymorphisms in Ecuador have higher frequencies if we compare with others around the world, with the exception of some South American population in Brazil and Chile.

  18. GLOBAL WARMING AND CLIMATE CHANGE IN SOUTH AMERICA

    Directory of Open Access Journals (Sweden)

    PATRICK PATERSON

    2017-12-01

    Full Text Available Global warming presents one of the most serious threats to South American nations. Countries in the region are at risk of a variety of climate change related problems: rising sea levels, diminishing potable water supplies, forest res, intense storms and ooding, heat waves and the spread of diseases. These disasters are occurring more frequently in the region and will likely increase in intensity also. The armed forces in the region are the only government departments with both the capacity and the manpower to respond to these massive catastrophes. Military support to civilian authorities will be required more frequently and under more severe conditions as climate change conditions worsen.

  19. Assessing the seismic risk potential of South America

    Science.gov (United States)

    Jaiswal, Kishor; Petersen, Mark D.; Harmsen, Stephen; Smoczyk, Gregory M.

    2016-01-01

    We present here a simplified approach to quantifying regional seismic risk. The seismic risk for a given region can be inferred in terms of average annual loss (AAL) that represents long-term value of earthquake losses in any one year caused from a long-term seismic hazard. The AAL are commonly measured in the form of earthquake shaking-induced deaths, direct economic impacts or indirect losses caused due to loss of functionality. In the context of South American subcontinent, the analysis makes use of readily available public data on seismicity, population exposure, and the hazard and vulnerability models for the region. The seismic hazard model was derived using available seismic catalogs, fault databases, and the hazard methodologies that are analogous to the U.S. Geological Survey’s national seismic hazard mapping process. The Prompt Assessment of Global Earthquakes for Response (PAGER) system’s direct empirical vulnerability functions in terms of fatality and economic impact were used for performing exposure and risk analyses. The broad findings presented and the risk maps produced herein are preliminary, yet they do offer important insights into the underlying zones of high and low seismic risks in the South American subcontinent. A more detailed analysis of risk may be warranted by engaging local experts, especially in some of the high risk zones identified through the present investigation.

  20. CRUSTAL THICKNESS VARIATIONS AND SEISMICITY OF NORTHWESTERN SOUTH AMERICA

    Directory of Open Access Journals (Sweden)

    Woo Kim Jeong

    2007-06-01

    Full Text Available Any uncompensated mass of the northern Andes Mountains is presumably under pressure to adjust within the Earth to its ideal state of isostatic equilibrium. Isostasy is the ideal state that any
    uncompensated mass seeks to achieve in time. These pressures interact with the relative motions between adjacent plates that give rise to earthquakes along the plate boundaries. By combining the
    gravity MOHO estimates and crustal discontinuities with historical and instrumental seismological catalogs the correlation between isostatically disturbed terrains and seismicity has been established.
    The thinner and thicker crustal regions were mapped from the zero horizontal curvature of the crustal thickness estimates. These boundaries or edges of crustal thickness variations were compared to
    crustal discontinuities inferred from gravity and magnetic anomalies and the patterns of seismicity that have been catalogued for the last 363 years. The seismicity is very intense along the Nazca-North
    Andes, Caribbean-North American and North Andes-South American collision zones and associated with regional tectonic compressional stresses that have locally increased and/or diminished by
    compressional and tensional stress, respectively, due to crustal thickness variations. High seismicity is also associated with the Nazca-Cocos diverging plate boundary whereas low seismicity is associated with the Panama-Nazca Transform Fault and the South American Plate.

  1. Biogeographic range expansion into South America by Coccidioides immitis mirrors New World patterns of human migration

    Science.gov (United States)

    Fisher, Matthew C.; Koenig, Gina L.; White, Thomas J.; San-Blas, Gioconda; Negroni, Ricardo; Alvarez, Isidro Gutiérrez; Wanke, Bodo; Taylor, John W.

    2001-01-01

    Long-distance population dispersal leaves its characteristic signature in genomes, namely, reduced diversity and increased linkage between genetic markers. This signature enables historical patterns of range expansion to be traced. Herein, we use microsatellite loci from the human pathogen Coccidioides immitis to show that genetic diversity in this fungus is geographically partitioned throughout North America. In contrast, analyses of South American C. immitis show that this population is genetically depauperate and was founded from a single North American population centered in Texas. Variances of allele distributions show that South American C. immitis have undergone rapid population growth, consistent with an epidemic increase in postcolonization population size. Herein, we estimate the introduction into South America to have occurred within the last 9,000–140,000 years. This range increase parallels that of Homo sapiens. Because of known associations between Amerindians and this fungus, we suggest that the colonization of South America by C. immitis represents a relatively recent and rapid codispersal of a host and its pathogen. PMID:11287648

  2. Institutional Status of BRICS and Pragmatic Cooperation:The Case of South America

    Directory of Open Access Journals (Sweden)

    Ernani Contipelli

    2015-05-01

    Full Text Available As a group formed by emerging powers, the BRICS is characterized by its particular profile: a pragmatic politic strategythat presents contradictory actions between its members. Internal cooperation among the BRICS members is becomingmore “institutional” with the creation of its financial institutions, the New Development Bank (NDB and the ContingencyReserve Agreement (CRA. These have led the group to a next stage in its history without changing its essence. The NDBhas been created to mobilize resources for infrastructure and sustainable development projects in emerging and developingcountries, and the CRA has been established to provide liquidity to countries experiencing difficulties in their balance ofpayment and to head off future economic crises. Many developing countries are closely observing these financial institutions.South America appears particularly interested to take advantage of them by attracting investments and obtainingloans from BRICS members in order to develop infrastructure in their countries and to build more informal relationshipswith foreign partners with reduced political commitments. For South America, the BRICS is an example of a pragmaticformula for cooperation in contrast to the modus operandi of traditional powers. In other words, poor countries would havean alternative to the International Monetary Fund and World Bank. Relations between the BRICS and South America arecharacterized by a pragmatic approach that reflects the “way of being” of the group and the necessities of modernization ofthe region. This article analyzes the particular relationship that BRICS is establishing with the countries of South Americausing its institutional status and pragmatic approach.

  3. Eocene primates of South America and the African origins of New World monkeys

    Science.gov (United States)

    Bond, Mariano; Tejedor, Marcelo F.; Campbell, Kenneth E.; Chornogubsky, Laura; Novo, Nelson; Goin, Francisco

    2015-04-01

    The platyrrhine primates, or New World monkeys, are immigrant mammals whose fossil record comes from Tertiary and Quaternary sediments of South America and the Caribbean Greater Antilles. The time and place of platyrrhine origins are some of the most controversial issues in primate palaeontology, although an African Palaeogene ancestry has been presumed by most primatologists. Until now, the oldest fossil records of New World monkeys have come from Salla, Bolivia, and date to approximately 26 million years ago, or the Late Oligocene epoch. Here we report the discovery of new primates from the ?Late Eocene epoch of Amazonian Peru, which extends the fossil record of primates in South America back approximately 10 million years. The new specimens are important for understanding the origin and early evolution of modern platyrrhine primates because they bear little resemblance to any extinct or living South American primate, but they do bear striking resemblances to Eocene African anthropoids, and our phylogenetic analysis suggests a relationship with African taxa. The discovery of these new primates brings the first appearance datum of caviomorph rodents and primates in South America back into close correspondence, but raises new questions about the timing and means of arrival of these two mammalian groups.

  4. Oroya fever and verruga peruana: bartonelloses unique to South America.

    Directory of Open Access Journals (Sweden)

    Michael F Minnick

    2014-07-01

    Full Text Available Bartonella bacilliformis is the bacterial agent of Carrión's disease and is presumed to be transmitted between humans by phlebotomine sand flies. Carrión's disease is endemic to high-altitude valleys of the South American Andes, and the first reported outbreak (1871 resulted in over 4,000 casualties. Since then, numerous outbreaks have been documented in endemic regions, and over the last two decades, outbreaks have occurred at atypical elevations, strongly suggesting that the area of endemicity is expanding. Approximately 1.7 million South Americans are estimated to be at risk in an area covering roughly 145,000 km2 of Ecuador, Colombia, and Peru. Although disease manifestations vary, two disparate syndromes can occur independently or sequentially. The first, Oroya fever, occurs approximately 60 days following the bite of an infected sand fly, in which infection of nearly all erythrocytes results in an acute hemolytic anemia with attendant symptoms of fever, jaundice, and myalgia. This phase of Carrión's disease often includes secondary infections and is fatal in up to 88% of patients without antimicrobial intervention. The second syndrome, referred to as verruga peruana, describes the endothelial cell-derived, blood-filled tumors that develop on the surface of the skin. Verrugae are rarely fatal, but can bleed and scar the patient. Moreover, these persistently infected humans provide a reservoir for infecting sand flies and thus maintaining B. bacilliformis in nature. Here, we discuss the current state of knowledge regarding this life-threatening, neglected bacterial pathogen and review its host-cell parasitism, molecular pathogenesis, phylogeny, sand fly vectors, diagnostics, and prospects for control.

  5. Quality of asthma care: Western Cape Province, South Africa | Mash ...

    African Journals Online (AJOL)

    Background. Asthma is the eighth leading contributor to the burden of disease in South Africa, but has received less attention than other chronic diseases. The Asthma Guidelines Implementation Project (AGIP) was established to improve the impact of the South African guidelines for chronic asthma in adults and ...

  6. The institutional foundations of energetic integration at the South America; Os fundamentos institucionais na integracao energetica da America do Sul

    Energy Technology Data Exchange (ETDEWEB)

    Suarez, Lizett Paola Lopez; Guerra, Sinclair Mallet-Guy [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Energia]. E-mails: lizlosu@fem.unicamp.br, sguerra@fem.unicamp.br; Udaeta, Miguel Edgar Morales [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Eletrotecnica e Energia (IEE)]. E-mail: udaeta@pea.usp.br

    2006-07-01

    From the revision and analysis of the energy integration process in South America, the present article goals to show which are the institutional basis that endorse the process, once these entities act directly with questions related to the energy sector or to the wider economic integration where the energy integration is inserted. Thus, the Regional entities, that can be associations, organizations and commissions, like ALADI, ARPEL, CEPAL, CIER, OLADE and others are mentioned and analyzed. The analysis points out that these entities constitute the institutional basis for support the decision making of the region countries, considering the achieved studies, the promoted debates, the establishment of norms and information treatment. Finally, it is emphasized that these entities can not and should not have decide and execute, since are the governments (politic will) the responsible for the planning and coordination role for having the integration project effectively implemented. (author)

  7. Governance, agricultural intensification, and land sparing in tropical South America

    Science.gov (United States)

    Ceddia, Michele Graziano; Bardsley, Nicholas Oliver; Gomez-y-Paloma, Sergio; Sedlacek, Sabine

    2014-01-01

    In this paper we address two topical questions: How do the quality of governance and agricultural intensification impact on spatial expansion of agriculture? Which aspects of governance are more likely to ensure that agricultural intensification allows sparing land for nature? Using data from the Food and Agriculture Organization, the World Bank, the World Database on Protected Areas, and the Yale Center for Environmental Law and Policy, we estimate a panel data model for six South American countries and quantify the effects of major determinants of agricultural land expansion, including various dimensions of governance, over the period 1970–2006. The results indicate that the effect of agricultural intensification on agricultural expansion is conditional on the quality and type of governance. When considering conventional aspects of governance, agricultural intensification leads to an expansion of agricultural area when governance scores are high. When looking specifically at environmental aspects of governance, intensification leads to a spatial contraction of agriculture when governance scores are high, signaling a sustainable intensification process. PMID:24799696

  8. The Brasiliano collage in South America: a review

    Directory of Open Access Journals (Sweden)

    Benjamim Bley de Brito Neves

    Full Text Available Analysis of recent geological and geochronological data from the basement of the South American platform indicates that the Brasiliano orogenic collage took place in four distinct pulses: a Early Cryogenian (ca. 800 - 740Ma; b Late Cryogenian-Early Ediacaran (ca. 660 - 610 Ma; c Early-Middle Ediacaran (c. 590 - 560 Ma; and d Late Cambrian (520 - 500 Ma. The first three pulses are well represented in most Neoproterozoic structural provinces in West Gondwana. The youngest orogenic phase/pulse, however, is only seen in Argentina (Pampean Orogeny and Brazil, in eastern Rio de Janeiro State (Búzios Orogeny. The period between ca. 750 and 500 Ma is comparable to that reported for the amalgamation of various continental fragments in East (Arabian-Nubian, Mozambique, Kuunga and North Gondwana (Cadomian. However, important differences in the nature and ages of events are recognized, which can be expected in view of the magnitude of Gondwana agglutination and the diversity of paleogeographic and tectonic scenarios. West Gondwana shows an interesting peculiarity: lithologically and tectonically diversified Tonian terranes underlie Brasiliano orogenic buildups. They were strongly reworked during most of the orogenic pulses. The Tonian terranes (1000 - 900 Ma and their relation with Rodinia or with the processes of Gondwana fusion remains an open question. Indications of their presence in East Gondwana are still poorly documented.

  9. Status of nuclear power programs in South America

    International Nuclear Information System (INIS)

    Spitalnik, J.

    2010-10-01

    Analysis of nuclear power plants construction in four South American countries - Argentina, Brazil, Chile and Uruguay - is made based on programs set up by government specialized agencies. In Argentina, in a time-span up to 2023, the nuclear power program considers a five-fold increase of the current installed capacity reaching some 5,000 M We. The Brazilian reference scenario will install additional 4,000 M We, up to 2030, to reach a total installed capacity of about 6,000 M We. Other scenarios could bring this total to some 8,000 - 10,000 M We. Chile and Uruguay have started strategic studies to place the nuclear power option in the future energy matrix of the country. The government of Chile set up, in 2007, a Task Group to determine whether nuclear power could be considered a viable option. This Group concluded that nuclear power is a mature, safe competitive, and low carbon emitter technology that could be considered a viable option. A Nuclear Advisory Group was created who made studies to install a nuclear power plant in the 2016-2021 time-span. In December 2008, the Uruguayan Government created a high level Working Group to establish the feasibility conditions for Nuclear Power Generation in the country. (Author)

  10. Governance, agricultural intensification, and land sparing in tropical South America.

    Science.gov (United States)

    Ceddia, Michele Graziano; Bardsley, Nicholas Oliver; Gomez-y-Paloma, Sergio; Sedlacek, Sabine

    2014-05-20

    In this paper we address two topical questions: How do the quality of governance and agricultural intensification impact on spatial expansion of agriculture? Which aspects of governance are more likely to ensure that agricultural intensification allows sparing land for nature? Using data from the Food and Agriculture Organization, the World Bank, the World Database on Protected Areas, and the Yale Center for Environmental Law and Policy, we estimate a panel data model for six South American countries and quantify the effects of major determinants of agricultural land expansion, including various dimensions of governance, over the period 1970-2006. The results indicate that the effect of agricultural intensification on agricultural expansion is conditional on the quality and type of governance. When considering conventional aspects of governance, agricultural intensification leads to an expansion of agricultural area when governance scores are high. When looking specifically at environmental aspects of governance, intensification leads to a spatial contraction of agriculture when governance scores are high, signaling a sustainable intensification process.

  11. High level of molecular and phenotypic biodiversity in Jatropha curcas from Central America compared to Africa, Asia and South America

    Science.gov (United States)

    2014-01-01

    Background The main bottleneck to elevate jatropha (Jatropha curcas L.) from a wild species to a profitable biodiesel crop is the low genetic and phenotypic variation found in different regions of the world, hampering efficient plant breeding for productivity traits. In this study, 182 accessions from Asia (91), Africa (35), South America (9) and Central America (47) were evaluated at genetic and phenotypic level to find genetic variation and important traits for oilseed production. Results Genetic variation was assessed with SSR (Simple Sequence Repeat), TRAP (Target Region Amplification Polymorphism) and AFLP (Amplified fragment length polymorphism) techniques. Phenotypic variation included seed morphological characteristics, seed oil content and fatty acid composition and early growth traits. Jaccard’s similarity and cluster analysis by UPGM (Unweighted Paired Group Method) with arithmetic mean and PCA (Principle Component Analysis) indicated higher variability in Central American accessions compared to Asian, African and South American accessions. Polymorphism Information Content (PIC) values ranged from 0 to 0.65. In the set of Central American accessions. PIC values were higher than in other regions. Accessions from the Central American population contain alleles that were not found in the accessions from other populations. Analysis of Molecular Variance (AMOVA; P jatropha oil significantly differed (P < 0.05) between regions. Conclusions The pool of Central American accessions showed very large genetic variation as assessed by DNA-marker variation compared to accessions from other regions. Central American accessions also showed the highest phenotypic variation and should be considered as the most important source for plant breeding. Some variation in early growth traits was found within a group of accessions from Asia and Africa, while these accessions did not differ in a single DNA-marker, possibly indicating epigenetic variation. PMID:24666927

  12. Maps showing geology, oil and gas fields, and geological provinces of South America

    Science.gov (United States)

    Schenk, C. J.; Viger, R.J.; Anderson, C.P.

    1999-01-01

    This digitally compiled map includes geology, geologic provinces, and oil and gas fields of South America. The map is part of a worldwide series on CD-ROM by World Energy Project released of the U.S. Geological Survey . The goal of the project is to assess the undiscovered, technically recoverable oil and gas resources of the world and report these results by the year 2000. For data management purposes the world is divided into eight energy regions corresponding approximately to the economic regions of the world as defined by the U.S. Department of State. South America (Region 6) includes Argentina, Bolivia, Brazil, Chile, Columbia, Ecuador, Falkland Islands, French Guiana, Guyuna, Netherlands, Netherlands Antilles, Paraguay, Peru, Suriname, Trinidad and Tobago, Uruguay, and Venezuela.

  13. Breakup of pangaea and isolation of relict mammals in australia, South america, and madagascar.

    Science.gov (United States)

    Fooden, J

    1972-02-25

    The composition of aboriginal land mammal faunas in Australia and New Guinea (prototherians and metatherians), South America (metatherians and eutherians) and Madagascar (eutherians only) is reconsidered in light of continental drift reconstructions of Mesozoic-Tertiary world paleogeography It is proposed that these three faunas represent successively detached samples of the evolving world mammal fauna as it existed when each of these land masses became faunally isolated from the rest of the world as a result of the progressive fragmentation of Pangaea. Isolation of aboriginal prototherians and metatherians in Australia and New Guinea may date from the Upper JurassicLower Cretaceous; isolation of aboriginal metatherians and eutherians in South America may date from the Middle Cretaceous-Upper Cretaceous; isolation of aboriginal eutherians in Madagascar may date from the Paleocene-Eocene.

  14. Homologous Recombination and Xylella fastidiosa Host-Pathogen Associations in South America.

    Science.gov (United States)

    Coletta-Filho, Helvécio D; Francisco, Carolina S; Lopes, João R S; Muller, Christiane; Almeida, Rodrigo P P

    2017-03-01

    Homologous recombination affects the evolution of bacteria such as Xylella fastidiosa, a naturally competent plant pathogen that requires insect vectors for dispersal. This bacterial species is taxonomically divided into subspecies, with phylogenetic clusters within subspecies that are host specific. One subspecies, pauca, is primarily limited to South America, with the exception of recently reported strains in Europe and Costa Rica. Despite the economic importance of X. fastidiosa subsp. pauca in South America, little is known about its genetic diversity. Multilocus sequence typing (MLST) has previously identified six sequence types (ST) among plant samples collected in Brazil (both subsp. pauca and multiplex). Here, we report on a survey of X. fastidiosa genetic diversity (MLST based) performed in six regions in Brazil and two in Argentina, by sampling five different plant species. In addition to the six previously reported ST, seven new subsp. pauca and two new subsp. multiplex ST were identified. The presence of subsp. multiplex in South America is considered to be the consequence of a single introduction from its native range in North America more than 80 years ago. Different phylogenetic approaches clustered the South American ST into four groups, with strains infecting citrus (subsp. pauca); coffee and olive (subsp. pauca); coffee, hibiscus, and plum (subsp. pauca); and plum (subsp. multiplex). In areas where these different genetic clusters occurred sympatrically, we found evidence of homologous recombination in the form of bidirectional allelic exchange between subspp. pauca and multiplex. In fact, the only strain of subsp. pauca isolated from a plum host had an allele that originated from subsp. multiplex. These signatures of bidirectional homologous recombination between endemic and introduced ST indicate that gene flow occurs in short evolutionary time frames in X. fastidiosa, despite the ecological isolation (i.e., host plant species) of genotypes.

  15. Special challenges in the conservation of fishes and aquatic environments of South America.

    Science.gov (United States)

    Costa, M F; Barletta, M

    2016-07-01

    In South America, the conservation of natural resources, particularly in relation to water and aquatic fauna, is an often-discussed issue. Unfortunately, there is still a large gap between thoughts and action. Scientists from different countries of the continent have however, produced a significant body of literature that should finally become the basis of emerging managerial models. © 2016 The Fisheries Society of the British Isles.

  16. A Cutaneous Ulcer Resulting from Mycobacterium ulcerans—Leishmania braziliensis Coinfection in South America

    Science.gov (United States)

    Mougin, Benjamin; Avenel-Audran, Martine; Hasseine, Lilia; Martin, Ludovic; Cottin, Jane; Pomares, Christelle; Delaunay, Pascal; Marty, Pierre; Ravel, Christophe; Chabasse, Dominique; Abgueguen, Pierre

    2011-01-01

    Buruli ulcer is a tropical skin disease caused by Mycobacterium ulcerans. Its mode of transmission is not yet clearly understood. We report here a cutaneous ulcer in a European traveler in South America resulting from a coinfection detected specifically for Mycobacterium ulcerans and Leishmania braziliensis DNA with real-time polymerase chain reaction. This observation of a unique cutaneous ulcer raises the issue about possible modes of transmission of those two pathogens by the same vector. PMID:22049045

  17. Microturbine applications for the oil and gas industries of South America

    Energy Technology Data Exchange (ETDEWEB)

    Richards, Lee [Capstone Turbine Corp., Chatsworth, CA (United States); Vescovo, Edgardo [Capstone Turbine Corp. South America (Colombia)

    2008-07-01

    This paper will describe the application of power generation by the use of microturbine technology by Capstone Turbine Corporation throughout South America. The purpose of this paper is to describe the technology and the experience gained over the last six years. The microturbines are power generation systems that produce energy from a diverse range of liquid or gaseous fuels. The generator is driven by a small gas turbine with a common shaft for the rotors of the generator and the engine. (author)

  18. Marine fronts at the continental shelves of austral South America - Physical and ecological processes

    Science.gov (United States)

    Acha, Eduardo M.; Mianzan, Hermes W.; Guerrero, Raúl A.; Favero, Marco; Bava, José

    2004-01-01

    Neritic fronts are very abundant in austral South America, covering several scales of space and time. However, this region is poorly studied from a systemic point of view. Our main goal is to develop a holistic view of physical and ecological patterns and processes at austral South America, regarding frontal arrangements. Satellite information (sea surface temperature and chlorophyll concentration), and historical hydrographic data were employed to show fronts. We compiled all existing evidence (physical and biological) about fronts to identify regions defined by similar types of coastal fronts and to characterize them. Fronts in austral South America can be arranged in six zones according to their location, main forcing, key physical variables, seasonality, and enrichment mechanisms. Four zones, the Atlantic upwelling zone; the temperate estuarine zone; the Patagonian tidal zone and the Argentine shelf-break zone, occupy most of the Atlantic side. The Chile-Peru upwelling zone, on the Pacific, is the largest and best-known region. The Patagonian cold estuarine zone encompasses the tip of South America, connecting the Pacific and Atlantic oceans, and remains poorly studied. When observed at a continental scale, the Pacific coast dominated by two large frontal zones appears simplest than the Atlantic coast in terms of frontal richness. The extension of the continental shelf in the Atlantic coast allows for the development of a great diversity of mesoscale fronts. Though frontal zones we defined are extensive areas of the continental shelves, fronts inside the zones are comparatively small areas. Even so, they play a paramount role in ecological processes, allowing for high biological production; offering feeding and/or reproductive habitats for fishes, squids, and birds; acting as retention areas for larvae of benthic species; and promoting establishment of benthic invertebrates that benefit from the organic production in the frontal area.

  19. Arrival of Paleo-Indians to the southern cone of South America: new clues from mitogenomes.

    Directory of Open Access Journals (Sweden)

    Michelle de Saint Pierre

    Full Text Available With analyses of entire mitogenomes, studies of Native American mitochondrial DNA (MTDNA variation have entered the final phase of phylogenetic refinement: the dissection of the founding haplogroups into clades that arose in America during and after human arrival and spread. Ages and geographic distributions of these clades could provide novel clues on the colonization processes of the different regions of the double continent. As for the Southern Cone of South America, this approach has recently allowed the identification of two local clades (D1g and D1j whose age estimates agree with the dating of the earliest archaeological sites in South America, indicating that Paleo-Indians might have reached that region from Beringia in less than 2000 years. In this study, we sequenced 46 mitogenomes belonging to two additional clades, termed B2i2 (former B2l and C1b13, which were recently identified on the basis of mtDNA control-region data and whose geographical distributions appear to be restricted to Chile and Argentina. We confirm that their mutational motifs most likely arose in the Southern Cone region. However, the age estimate for B2i2 and C1b13 (11-13,000 years appears to be younger than those of other local clades. The difference could reflect the different evolutionary origins of the distinct South American-specific sub-haplogroups, with some being already present, at different times and locations, at the very front of the expansion wave in South America, and others originating later in situ, when the tribalization process had already begun. A delayed origin of a few thousand years in one of the locally derived populations, possibly in the central part of Chile, would have limited the geographical and ethnic diffusion of B2i2 and explain the present-day occurrence that appears to be mainly confined to the Tehuelche and Araucanian-speaking groups.

  20. Lithium Geopolitics in South America and the divergents national public policies

    Directory of Open Access Journals (Sweden)

    Bernardo Salgado Rodrigues

    2016-12-01

    Full Text Available This article seeks to address the geopolitics of lithium in South America from the analysis of Argentine, Bolivian and Chilean public policies. Our hypothesis is that there is an institutional divergence between these countries with different projects related to this natural resource. From a geostrategic vision, we argued that regional integration can play a key role in the sovereignty of lithium for countries and their societies.

  1. A multi-criteria decision analysis approach to assessing malaria risk in northern South America

    Directory of Open Access Journals (Sweden)

    Temitope O. Alimi

    2016-03-01

    Full Text Available Abstract Background Malaria control in South America has vastly improved in the past decade, leading to a decrease in the malaria burden. Despite the progress, large parts of the continent continue to be at risk of malaria transmission, especially in northern South America. The objectives of this study were to assess the risk of malaria transmission and vector exposure in northern South America using multi-criteria decision analysis. Methods The risk of malaria transmission and vector exposure in northern South America was assessed using multi-criteria decision analysis, in which expert opinions were taken on the key environmental and population risk factors. Results Results from our risk maps indicated areas of moderate-to-high risk along rivers in the Amazon basin, along the coasts of the Guianas, the Pacific coast of Colombia and northern Colombia, in parts of Peru and Bolivia and within the Brazilian Amazon. When validated with occurrence records for malaria, An. darlingi, An. albimanus and An. nuneztovari s.l., t-test results indicated that risk scores at occurrence locations were significantly higher (p < 0.0001 than a control group of geographically random points. Conclusion In this study, we produced risk maps based on expert opinion on the spatial representation of risk of potential vector exposure and malaria transmission. The findings provide information to the public health decision maker/policy makers to give additional attention to the spatial planning of effective vector control measures. Therefore, as the region tackles the challenge of malaria elimination, prioritizing areas for interventions by using spatially accurate, high-resolution (1 km or less risk maps may guide targeted control and help reduce the disease burden in the region.

  2. The first Triassic dipteran (Insecta) from South America, with review of Hennigmatidae.

    Science.gov (United States)

    Lara, María Belén; Lukashevich, Elena D

    2013-01-01

    The first Triassic dipteran from South America is described based on an isolated wing from the lower Upper Triassic deposits of Argentina (Mendoza Province, Potrerillos Formation, Quebrada del Durazno locality). Trihennigma zavattierii gen. et sp. nov. is a member of the Mesozoic family Hennigmatidae, previously recorded only from Eurasia. A key for the genera and species of Hennigmatidae is provided and systematic position of the taxa is discussed.

  3. THE MILITARY STATE IN SOUTH AMERICA: INTERVENTIONISM, CAUDILLOS AND ARMED FORCES

    OpenAIRE

    PEDRO RIVAS NIETO

    2018-01-01

    In this work the author analyzes the elements of the Military State, which was the result of National Security Regimes. They ruled South America during the last third of the 20th century. The behaviour of the Armed Forces is compared with that of the classic caudillos. The Armed Forces-Civil Society relationship is studied too. And, of course, the intervention in political issues by the military and their relationship with political parties is also analyzed, as well. The conclusion ends with ...

  4. First report of Raoiella indica Hirst (Acari: Tenuipalpidae) in South America

    International Nuclear Information System (INIS)

    Vasquez, Carlos; Quiros de G, Magally; Aponte, Orlando; Sandoval, D. Maria F.

    2008-01-01

    The presence of the red palm mite, Raoiella indica Hirst is recorded for the first time in South America. High populations and severe damages caused by this new invasive mite were found on coconut and banana leaves in Sucre (10 deg 27' 47 N and 64 deg 10' 38 W ) and Monagas (9 deg 46'60 N and 63 deg 12'0 W ) states in northeastern Venezuela. (author)

  5. Cornerstones of a renewable energy law for emerging markets in South America

    International Nuclear Information System (INIS)

    Kissel, Johannes M.; Hanitsch, Rolf; Krauter, Stefan C.W.

    2009-01-01

    Since 1990, effective support schemes for renewable energies have been introduced mainly in European countries. In this article, the authors explain which consequences different general conditions could have on the design and functioning of feed-in laws. Cornerstones for an adjusted feed-in law to the particular general conditions of emerging and developing countries in South America will be drawn, which should give support to the decision-makers for designing an attuned and well-functioning feed-in legislation.

  6. Insecta, Coleoptera, Cerambycidae, Cerambycinae, Trachyderini: New state and country records from South America

    Directory of Open Access Journals (Sweden)

    Quintino, H. Y. S.

    2010-01-01

    Full Text Available Based on the revision of the collections of the Museu Nacional, Universidade Federal do Rio de Janeiro andthe National Museum of Natural History, Smithsonian Institution, the current work provides new localities for 32 speciesand two subspecies of Trachyderini from South America. Thirteen new country records from Argentina, Brazil, Colombia,Ecuador, Peru, Surinam and Venezuela and 35 new state records from Brazil are registered.

  7. Multiscale perspectives of fire, climate and humans in western North America and the Jemez Mountains, USA.

    Science.gov (United States)

    Swetnam, Thomas W; Farella, Joshua; Roos, Christopher I; Liebmann, Matthew J; Falk, Donald A; Allen, Craig D

    2016-06-05

    Interannual climate variations have been important drivers of wildfire occurrence in ponderosa pine forests across western North America for at least 400 years, but at finer scales of mountain ranges and landscapes human land uses sometimes over-rode climate influences. We reconstruct and analyse effects of high human population densities in forests of the Jemez Mountains, New Mexico from ca 1300 CE to Present. Prior to the 1680 Pueblo Revolt, human land uses reduced the occurrence of widespread fires while simultaneously adding more ignitions resulting in many small-extent fires. During the 18th and 19th centuries, wet/dry oscillations and their effects on fuels dynamics controlled widespread fire occurrence. In the late 19th century, intensive livestock grazing disrupted fuels continuity and fire spread and then active fire suppression maintained the absence of widespread surface fires during most of the 20th century. The abundance and continuity of fuels is the most important controlling variable in fire regimes of these semi-arid forests. Reduction of widespread fires owing to reduction of fuel continuity emerges as a hallmark of extensive human impacts on past forests and fire regimes.This article is part of the themed issue 'The interaction of fire and mankind'. © 2016 The Authors.

  8. A robust null hypothesis for the potential causes of megadrought in western North America

    Science.gov (United States)

    Ault, T.; St George, S.; Smerdon, J. E.; Coats, S.; Mankin, J. S.; Cruz, C. C.; Cook, B.; Stevenson, S.

    2017-12-01

    The western United States was affected by several megadroughts during the last 1200 years, most prominently during the Medieval Climate Anomaly (MCA: 800 to 1300 CE). A null hypothesis is developed to test the possibility that, given a sufficiently long period of time, these events are inevitable and occur purely as a consequence of internal climate variability. The null distribution of this hypothesis is populated by a linear inverse model (LIM) constructed from global sea-surface temperature anomalies and self-calibrated Palmer Drought Severity Index data for North America. Despite being trained only on seasonal data from the late 20th century, the LIM produces megadroughts that are comparable in their duration, spatial scale, and magnitude as the most severe events of the last 12 centuries. The null hypothesis therefore cannot be rejected with much confidence when considering these features of megadrought, meaning that similar events are possible today, even without any changes to boundary conditions. In contrast, the observed clustering of megadroughts in the MCA, as well as the change in mean hydroclimate between the MCA and the 1500-2000 period, are more likely to have been caused by either external forcing or by internal climate variability not well sampled during the latter half of the Twentieth Century. Finally, the results demonstrate the LIM is a viable tool for determining whether paleoclimate reconstructions events should be ascribed to external forcings, "out of sample" climate mechanisms, or if they are consistent with the variability observed during the recent period.

  9. Large projected increases in rain-on-snow flood potential over western North America

    Science.gov (United States)

    Musselman, K. N.; Ikeda, K.; Barlage, M. J.; Lehner, F.; Liu, C.; Newman, A. J.; Prein, A. F.; Mizukami, N.; Gutmann, E. D.; Clark, M. P.; Rasmussen, R.

    2017-12-01

    In the western US and Canada, some of the largest annual flood events occur when warm storm systems drop substantial rainfall on extensive snow-cover. For example, last winter's Oroville dam crisis in California was exacerbated by rapid snowmelt during a rain-on-snow (ROS) event. We present an analysis of ROS events with flood-generating potential over western North America simulated at high-resolution by the Weather Research and Forecasting (WRF) model run for both a 13-year control time period and re-run with a `business-as-usual' future (2071-2100) climate scenario. Daily ROS with flood-generating potential is defined as rainfall of at least 10 mm per day falling on snowpack of at least 10 mm water equivalent, where the sum of rainfall and snowmelt contains at least 20% snowmelt. In a warmer climate, ROS is less frequent in regions where it is historically common, and more frequent elsewhere. This is evidenced by large simulated reductions in snow-cover and ROS frequency at lower elevations, particularly in warmer, coastal regions, and greater ROS frequency at middle elevations and in inland regions. The same trend is reflected in the annual-average ROS runoff volume (rainfall + snowmelt) aggregated to major watersheds; large reductions of 25-75% are projected for much of the U.S. Pacific Northwest, while large increases are simulated for the Colorado River basin, western Canada, and the higher elevations of the Sierra Nevada. In the warmer climate, snowmelt contributes substantially less to ROS runoff per unit rainfall, particularly in inland regions. The reduction in snowmelt contribution is due to a shift in ROS timing from warm spring events to cooler winter conditions and/or from warm, lower elevations to cool, higher elevations. However, the slower snowmelt is offset by an increase in rainfall intensity, maintaining the flood potential of ROS at or above historical levels. In fact, we report large projected increases in the intensity of extreme ROS events

  10. Burden of colorectal cancer in Central and South America.

    Science.gov (United States)

    Sierra, Monica S; Forman, David

    2016-09-01

    The colorectal cancer (CRC) burden is increasing in Central and South American due to an ongoing transition towards higher levels of human development. We describe the burden of CRC in the region and review the current status of disease control. We obtained regional- and national-level incidence data from 48 population-based cancer registries in 13 countries, as well as cancer deaths from the WHO mortality database for 18 countries. We estimated world population age-standardized incidence (ASR) and mortality (ASMR) rates per 100,000 person-years for 2003-2007 and the estimated annual percentage change for 1997-2008. The CRC rate in males was 1-2 times higher than that in females. In 2003-2007, the highest ASRs were seen in Uruguayan, Brazilian and Argentinean males (25.2-34.2) and Uruguayan and Brazilian females (21.5-24.7), while El Salvador had the lowest ASR in both sexes (males: 1.5, females: 1.3). ASMRs were<10 for both sexes, except in Uruguay, Cuba and Argentina (10.0-17.7 and 11.3-12.0). CRC incidence is increasing in Chilean males. Most countries have national screening guidelines. Uruguay and Argentina have implemented national screening programs. Geographic variation in CRC and sex gaps may be explained by differences in the prevalence of obesity, physical inactivity, diet, smoking and alcohol consumption, early detection, and cancer registration practices. Establishing optimal CRC screening programs is challenging due to lack of healthcare access and coverage, funding, regional differences and inadequate infrastructure, and may not be feasible. Given the current status of CRC in the region, data generated by population-based cancer registries is crucial for cancer control planning. Copyright © 2015 International Agency for Research on Cancer. Published by Elsevier Ltd.. All rights reserved.

  11. South America: Brazil leads the way in offshore drilling

    Energy Technology Data Exchange (ETDEWEB)

    1975-08-15

    Brazil has found more than 600 million barrels of oil in the Campos basin and made other strikes to the north, offshore Sergipe, Alagoas, and Rio Grande do Norte states. Argentina's government recently gave the state oil company (YPF) permission to prospect in the Falkland Islands area about 200 miles east of Argentina's southern tip. YPF also is expected to accelerate work offshore Tierra del Fuego next year. The nationalization of petroleum in Venezuela is discussed. Drilling activity has slowed to 67 percent of the level of 1974. The goal for 1975 is about 875 million barrels. Chile has revised its oil law to permit foreign companies to explore, develop and produce the country's resources via contracts. Despite spotty successes, Peru has not given up on the northeastern jungle area, just south of Ecuador's fields. Occidental Petroleum and Petroperu have been the only companies to find commercial oil in the four-year exploration period. Their reserves are put at 464 million barrels. Eighteen foreign companies signed 14 contracts covering more than 50,000 square miles in Bolivia since the country asked for outside help in 1972. Ecuador's output reached an all-time high of 244,000 bpd and then slowed down to a 27,000 bpd dribble when the Trans-Ecuador pipeline broke. The government decreed that production from the Texaco and Gulf fields in the Oriente must rise to 210,000 bopd and that the two companies must drill their unexplored and undeveloped acreage or lose it. Ecuador cut 43 cents from the price of oil by reducing the production tax. Colombia abolished all oil concessions this year in an attempt to stem steadily slipping production. Exploration activities in Uruguay and Paraguay are discussed. (MCW)

  12. Widespread occurrence of bd in French Guiana, South America.

    Directory of Open Access Journals (Sweden)

    Elodie A Courtois

    Full Text Available The amphibian chytrid fungus Batrachochytrium dendrobatidis (Bd is a purported agent of decline and extinction of many amphibian populations worldwide. Its occurrence remains poorly documented in many tropical regions, including the Guiana Shield, despite the area's high amphibian diversity. We conducted a comprehensive assessment of Bd in French Guiana in order to (1 determine its geographical distribution, (2 test variation of Bd prevalence among species in French Guiana and compare it to earlier reported values in other South American anuran species (http://www.bd-maps.net; 123 species from 15 genera to define sentinel species for future work, (3 track changes in prevalence through time and (4 determine if Bd presence had a negative effect on one selected species. We tested the presence of Bd in 14 species at 11 sites for a total of 1053 samples (306 in 2009 and 747 in 2012. At least one Bd-positive individual was found at eight out of 11 sites, suggesting a wide distribution of Bd in French Guiana. The pathogen was not uniformly distributed among the studied amphibian hosts, with Dendrobatidae species displaying the highest prevalence (12.4% as compared to Bufonidae (2.6 % and Hylidae (1.5%. In contrast to earlier reported values, we found highest prevalence for three Dendrobatidae species and two of them displayed an increase in Bd prevalence from 2009 to 2012. Those three species might be the sentinel species of choice for French Guiana. For Dendrobates tinctorius, of key conservation value in the Guiana Shield, smaller female individuals were more likely to be infected, suggesting either that frogs can outgrow their chytrid infections or that the disease induces developmental stress limiting growth. Generally, our study supports the idea that Bd is more widespread than previously thought and occurs at remote places in the lowland forest of the Guiana shield.

  13. Potential distribution of the invasive freshwater dinoflagellate Ceratium furcoides (Levander) Langhans (Dinophyta) in South America.

    Science.gov (United States)

    Meichtry de Zaburlín, Norma; Vogler, Roberto E; Molina, María J; Llano, Víctor M

    2016-04-01

    Dinoflagellates of the genus Ceratium are predominantly found in marine environments, with a few species in inland waters. Over the last decades, the freshwater species Ceratium hirundinella and Ceratium furcoides have colonized and invaded several South American basins. The purpose of this study was to create a distribution model for the invasive dinoflagellate C. furcoides in South America in order to further investigate the basins at potential risk, as well as the environmental conditions that influence its expansion. This species is known to develop blooms due to its mobility, resistance to sedimentation, and optimized use of resources. Although nontoxic, blooms of the species cause many problems to both the natural ecosystems and water users. Potential distribution was predicted by using a maximum entropy algorithm (MaxEnt). Model was run with 101 occurrences obtained from the scientific literature, and climatic, hydrological and topographic variables. The developed model had a very good performance for the study area. The most susceptible areas identified were mainly concentrated in the basins between southeastern Brazil and northeastern Argentina. Besides already affected regions, new potentially suitable areas were identified in temperate regions of South America. The information generated here will be useful for authorities responsible for water and watershed management to monitor the spread of this species and address problems related to its establishment in new environments. © 2015 Phycological Society of America.

  14. Predicting geographic distributions of Phacellodomus species (Aves: Furnariidae in South America based on ecological niche modeling

    Directory of Open Access Journals (Sweden)

    Maria da Salete Gurgel Costa

    2014-08-01

    Full Text Available Phacellodomus Reichenbach, 1853, comprises nine species of Furnariids that occur in South America in open and generally dry areas. This study estimated the geographic distributions of Phacellodomus species in South America by ecological niche modeling. Applying maximum entropy method, models were produced for eight species based on six climatic variables and 949 occurrence records. Since highest climatic suitability for Phacellodomus species has been estimated in open and dry areas, the Amazon rainforest areas are not very suitable for these species. Annual precipitation and minimum temperature of the coldest month are the variables that most influence the models. Phacellodomus species occurred in 35 ecoregions of South America. Chaco and Uruguayan savannas were the ecoregions with the highest number of species. Despite the overall connection of Phacellodomus species with dry areas, species such as P. ruber, P. rufifrons, P. ferrugineigula and P. erythrophthalmus occurred in wet forests and wetland ecoregions.

  15. South America electric power integration: an utopia or a reality?; Integracao eletrica sul-americana: utopia ou realidade?

    Energy Technology Data Exchange (ETDEWEB)

    Velez, Jaime

    2007-07-01

    The aim of this chapter is the discussing on the economic and institutional conditions necessary to the South America electric power integration in the context of the changes in the electric industry initiated on the 1980's years.

  16. The extreme 2014 flood in south-western Amazon basin: the role of tropical-subtropical South Atlantic SST gradient

    International Nuclear Information System (INIS)

    Espinoza, Jhan Carlo; Marengo, José Antonio; Ronchail, Josyane; Carpio, Jorge Molina; Flores, Luís Noriega; Guyot, Jean Loup

    2014-01-01

    Unprecedented wet conditions are reported in the 2014 summer (December–March) in South-western Amazon, with rainfall about 100% above normal. Discharge in the Madeira River (the main southern Amazon tributary) has been 74% higher than normal (58 000 m 3 s −1 ) at Porto Velho and 380% (25 000 m 3 s −1 ) at Rurrenabaque, at the exit of the Andes in summer, while levels of the Rio Negro at Manaus were 29.47 m in June 2014, corresponding to the fifth highest record during the 113 years record of the Rio Negro. While previous floods in Amazonia have been related to La Niña and/or warmer than normal tropical South Atlantic, the 2014 rainfall and flood anomalies are associated with warm condition in the western Pacific-Indian Ocean and with an exceptionally warm Subtropical South Atlantic. Our results suggest that the tropical and subtropical South Atlantic SST gradient is a main driver for moisture transport from the Atlantic toward south-western Amazon, and this became exceptionally intense during summer of 2014. (letter)

  17. Calculation of paleohydraulic parameters of a fluvial system under spatially variable subsidence, of the Ericson sandstone, South western Wyoming

    Science.gov (United States)

    Snyder, H.; Leva-Lopez, J.

    2017-12-01

    During the late Campanian age in North America fluvial systems drained the highlands of the Sevier orogenic belt and travelled east towards the Western Interior Seaway. One of such systems deposited the Canyon Creek Member (CCM) of the Ericson Formation in south-western Wyoming. At this time the fluvial system was being partially controlled by laterally variable subsidence caused by incipient Laramide uplifts. These uplifts rather than real topographic features were only areas of reduced subsidence at the time of deposition of the CCM. Surface expression at that time must have been minimum, only minute changes in slope and accommodation. Outcrops around these Laramide structures, in particular both flanks of the Rock Springs Uplift, the western side of the Rawlins uplift and the north flank of the Uinta Mountains, have been sampled to study the petrography, grain size, roundness and sorting of the CCM, which along with the cross-bed thickness and bar thickness allowed calculation of the hydraulic parameters of the rivers that deposited the CCM. This study reveals how the fluvial system evolved and responded to the very small changes in subsidence and slope. Furthermore, the petrography will shed light on the provenance of these sandstones and on the relative importance of Sevier sources versus Laramide sources. This work is framed in a larger study that shows how incipient Laramide structural highs modified the behavior, style and architecture of the fluvial system, affecting its thickness, facies characteristics and net-to-gross both down-dip and along strike across the basin.

  18. Brazilian foreign affairs: social capital and the democratic discourse in South America

    Directory of Open Access Journals (Sweden)

    Rafael Duarte Villa

    2007-01-01

    Full Text Available Brazilian elites as well as foreign policy-makers have long shared a common belief that the ideas of democracy and democratization should serve as some "road map" to foreign policy-making. In areas such as security, regional integration, and disarmament, the goal has been to generate a positive social capital as well as to build trusting relations with Brazilian neighbors in South America. Therefore, under the impact of ideas brought about by new world visions, Brazilian foreign policy has changed a domestic policy feature - the democratic rearrangement of the political system - into a condition and resource for foreign policy-making towards South America. The result has been a fine improvement of Brazilian image and credibility in the regional South American scenario. In other words, there has been a significant increment in "trust" towards Brazil. This argument has been developed based on extracts and transcripts from official diplomatic speeches from Brazilian foreign policy-makers as well as a historical reconstruction of Brazil's diplomatic relations with two South American countries. Our study was based on two cases: Brazilian-Venezuelan and Brazilian-Argentine relations in the 80's and the 90's.

  19. Latitudinal variation in photoperiodic response of the three-spined stickleback Gasterosteus aculeatus in western North America

    Science.gov (United States)

    Yeates-Burghart, Q. S.; O’Brien, C.; Cresko, W. A.; Holzapfel, C. M.; Bradshaw, W. E.

    2014-01-01

    Reproductive maturation in both male and female three-spined stickleback Gasterosteus aculeatus was strongly photoperiodic in a northern population (Alaska, 61° N) but not in a southern population (Oregon, 43° N) from western North America. Increasing reliance on photoperiod with increasing latitude is a general phenomenon among vertebrates, and is probably due to the anticipation of a narrower window of opportunity for reproduction and development at higher latitudes. PMID:20738673

  20. Mercury in western North America: A synthesis of environmental contamination, fluxes, bioaccumulation, and risk to fish and wildlife

    Science.gov (United States)

    Eagles-Smith, Collin A.; Wiener, James G.; Eckley, Chris S.; Willacker, James J.; Evers, David C.; Marvin-DiPasquale, Mark C.; Obrist, Daniel; Fleck, Jacob; Aiken, George R.; Lepak, Jesse M.; Jackson, Allyson K.; Webster, Jackson; Stewart, Robin; Davis, Jay; Alpers, Charles N.; Ackerman, Joshua T.

    2016-01-01

    Western North America is a region defined by extreme gradients in geomorphology and climate, which support a diverse array of ecological communities and natural resources. The region also has extreme gradients in mercury (Hg) contamination due to a broad distribution of inorganic Hg sources. These diverse Hg sources and a varied landscape create a unique and complex mosaic of ecological risk from Hg impairment associated with differential methylmercury (MeHg) production and bioaccumulation. Understanding the landscape-scale variation in the magnitude and relative importance of processes associated with Hg transport, methylation, and MeHg bioaccumulation requires a multidisciplinary synthesis that transcends small-scale variability. The Western North America Mercury Synthesis compiled, analyzed, and interpreted spatial and temporal patterns and drivers of Hg and MeHg in air, soil, vegetation, sediments, fish, and wildlife across western North America. This collaboration evaluated the potential risk from Hg to fish, and wildlife health, human exposure, and examined resource management activities that influenced the risk of Hg contamination. This paper integrates the key information presented across the individual papers that comprise the synthesis. The compiled information indicates that Hg contamination is widespread, but heterogeneous, across western North America. The storage and transport of inorganic Hg across landscape gradients are largely regulated by climate and land-cover factors such as plant productivity and precipitation. Importantly, there was a striking lack of concordance between pools and sources of inorganic Hg, and MeHg in aquatic food webs. Additionally, water management had a widespread influence on MeHg bioaccumulation in aquatic ecosystems, whereas mining impacts where relatively localized. These results highlight the decoupling of inorganic Hg sources with MeHg production and bioaccumulation. Together the findings indicate that developing

  1. Mercury content of shark from south-western Australian waters

    Energy Technology Data Exchange (ETDEWEB)

    Caputi, N.; Edmonds, J.S.; Heald, D.I.

    1979-11-01

    Muscle samples from four species of commercially sought sharks off the Western Australia coast were analyzed for total mercury. While substantial amounts of mercury were accumulated by sharks, as by other marine fish, the lack of polluting industry on the coast indicates that such mercury levels probably are natural. Mercury concentrations generally increased with fish size. (4 graphs, 1 map, 8 references, 2 tables)

  2. Tuberculosis drug resistance in the Western Cape | Weyer | South ...

    African Journals Online (AJOL)

    Objectives: Drug resistance is a serious problem in the treatment of tuberculosis and a threat to successful tuberculosis control programmes. Local health workers have expressed concern that the increasing tuberculosis epidemic in the Western Cape is partly attributable to drug resistance. The aim of this study was to ...

  3. Yersinia enterocolitica in the Western Cape | Finlayson | South ...

    African Journals Online (AJOL)

    Yersinia enterocolitica, serotype 3, phage type 9a, has been isolated for the first time in the Western Cape. Sera from 59 abattoir workers were investigated for the presence of 0 and H agglutinins. These were present in one sample, suggesting a past infection. Sera from 115 Nama-speaking adults of the Kuboes area ...

  4. Cutaneous adornment in the Yoruba of south-western Nigeria - past and present.

    Science.gov (United States)

    George, Adekunle O; Ogunbiyi, Adebola O; Daramola, Olaniyi O M

    2006-01-01

    The traditional practice of cutaneous adornment is rich and vast amongst the Yoruba in the south-western part of Nigeria. There are varieties of traditionally made products, such as oils, soaps, fragrances, and beads, that have been employed over the years to enhance body beauty. This rich cultural heritage, however, has more or less given way to the values of Western culture, together with the disadvantages of the latter, manifesting as sequelae on the skin.

  5. Disruption of ecosystem processes in western North America by invasive species

    Directory of Open Access Journals (Sweden)

    Jeffrey S. Dukes

    2004-09-01

    Full Text Available Many ecosystems of western North America have been dramatically changed by non-native species. Here, we review ecological impacts of 56 plant, animal, fungus, and protist species that were brought to this region by humans. We discuss characteristics of invasive species that can lead to major ecosystem impacts, and explore how invasive species alter many different attributes of ecosystems. Specifically, we include examples of invasive species that affect geomorphology, fire regimes, hydrology, microclimate, atmospheric composition, nutrient cycling, and productivity. Finally, we review the direct consequences of biological invasions for some native species. We summarize examples from this paper in Appendix 1. Our examples illustrate how, as invasive species have become dominant across large areas of western North America's grassland, shrubland, dune, riparian, and estuarine ecosystems, the properties and functioning of these systems have changed. To date, some systems in this region, such as its forests, remain relatively unaffected by invasive species. However, recent attacks of forest pathogens highlight the potential vulnerability of these ecosystemsMuchos ecosistemas de Norteamérica occidental han cambiado dramáticamente a causa del efecto producido por especies no autóctonas. Aquí se muestra una revisión del impacto ecológico producido por 56 especies diferentes de plantas, animales y hongos, y especies de protistas que fueron traídos a esta región por humanos. Discutimos las características de las especies invasoras que pueden producir un gran impacto en el ecosistema, y exploramos cómo las especies invasoras pueden alterar de forma muy diferente los atributos de un ecosistema. Específicamente, incluimos ejemplos de especies invasoras que afectan a la geomorfología, a los regímenes del fuego, a la hidrología, al microclima, a la composición atmosférica, al ciclo de nutrientes, y a la productividad. Finalmente, revisamos las

  6. Contrasting evidence of Holocene ice margin retreat, south-western Greenland

    DEFF Research Database (Denmark)

    Levy, L. B.; Larsen, N. K.; Davidson, T. A.

    2017-01-01

    Constraining the Greenland Ice Sheet's (GrIS) response to Holocene climate change provides calibrations for ice sheet models that hindcast past ice margin fluctuations. Ice sheet models predict enhanced ice retreat in south-western Greenland during the middle Holocene; however, few geological...... observations corroborating the extensive retreat are available. We present new data from lake sediment cores from the Isua region, south-western Greenland, which provide constraints on Holocene fluctuations of the GrIS margins. Our data indicate that the main GrIS margin was 30 km west of its present...

  7. Yersinia enterocolitica in the Western Cape | Finlayson | South ...

    African Journals Online (AJOL)

    South African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 47, No 1 (1973) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

  8. Brucellosis in childhood in the Western Cape | Hendricks | South ...

    African Journals Online (AJOL)

    South African Medical Journal. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 85, No 3 (1995) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register · Download this PDF file. The PDF file you selected should ...

  9. The impact of bark beetle infestations on monoterpene emissions and secondary organic aerosol formation in western North America

    Directory of Open Access Journals (Sweden)

    A. R. Berg

    2013-03-01

    Full Text Available Over the last decade, extensive beetle outbreaks in western North America have destroyed over 100 000 km2 of forest throughout British Columbia and the western United States. Beetle infestations impact monoterpene emissions through both decreased emissions as trees are killed (mortality effect and increased emissions in trees under attack (attack effect. We use 14 yr of beetle-induced tree mortality data together with beetle-induced monoterpene emission data in the National Center for Atmospheric Research (NCAR Community Earth System Model (CESM to investigate the impact of beetle-induced tree mortality and attack on monoterpene emissions and secondary organic aerosol (SOA formation in western North America. Regionally, beetle infestations may have a significant impact on monoterpene emissions and SOA concentrations, with up to a 4-fold increase in monoterpene emissions and up to a 40% increase in SOA concentrations in some years (in a scenario where the attack effect is based on observed lodgepole pine response. Responses to beetle attack depend on the extent of previous mortality and the number of trees under attack in a given year, which can vary greatly over space and time. Simulated enhancements peak in 2004 (British Columbia and 2008 (US. Responses to beetle attack are shown to be substantially larger (up to a 3-fold localized increase in summertime SOA concentrations in a scenario based on bark-beetle attack in spruce trees. Placed in the context of observations from the IMPROVE network, the changes in SOA concentrations due to beetle attack are in most cases small compared to the large annual and interannual variability in total organic aerosol which is driven by wildfire activity in western North America. This indicates that most beetle-induced SOA changes are not likely detectable in current observation networks; however, these changes may impede efforts to achieve natural visibility conditions in the national parks and wilderness

  10. MECO Warming Changes Continental Rainfall Patterns in Eocene Western North America

    Science.gov (United States)

    Methner, K.; Mulch, A.; Fiebig, J.; Wacker, U.; Gerdes, A.; Graham, S. A.; Chamberlain, C. P.

    2016-12-01

    Eocene hyperthermals represent temperature extremes superimposed on an existing warm climate. They dramatically affected the marine and terrestrial biosphere, but still remain among the most enigmatic phenomena of Cenozoic climate dynamics. To evaluate the impacts of global warm periods on terrestrial temperature and rainfall records in continental interiors, we sampled a suite of middle Eocene ( 40 Ma) paleosols from a high-elevation mammal fossil locality in the hinterland of the North American Cordillera (Sage Creek Basin, Montana, USA) and integrated laser ablation U-Pb dating of pedogenic carbonate, stable isotope (δ18O) and clumped isotope temperature (Δ47) records. Δ47 temperature data of soil carbonates progressively increase from 23 °C ±3 °C to peak temperatures of 32 °C ±3 °C and subsequently drop to 21 °C ±2 °C and delineate a rapid +9/-11 °C temperature excursion in the paleosol record. This hyperthermal event is accompanied by large and rapid shifts towards low δ18O values and reduced pedogenic CaCO3 contents. U-Pb geochronology of the paleosol carbonate confirms a middle Eocene age for soil carbonate formation (39.5 ±1.4 Ma and 40.1 ±0.8 Ma). Based on U-Pb geochronology, magneto- and biostratigraphy we suggest that the recorded Δ47 temperature excursion reflects peak warming during the Middle Eocene Climatic Optimum (MECO). The MECO in continental western North America appears to be characterized by warmer and wetter (sub-humid) conditions in this high-elevation site. Shifts in δ18O values of precipitation and pedogenic CaCO3 contents parallel temperature changes and require modification of mid-latitude rainfall patterns, indicating a profound impact of the MECO on the hydrological cycle and consequently on atmospheric circulation patterns in the hinterland of the North American Cordillera.

  11. Regional-Scale Declines in Productivity of Pink and Chum Salmon Stocks in Western North America

    Science.gov (United States)

    Malick, Michael J.; Cox, Sean P.

    2016-01-01

    Sockeye salmon (Oncorhynchus nerka) stocks throughout the southern part of their North American range have experienced declines in productivity over the past two decades. In this study, we tested the hypothesis that pink (O. gorbuscha) and chum (O. keta) salmon stocks have also experienced recent declines in productivity by investigating temporal and spatial trends in productivity of 99 wild North American pink and chum salmon stocks. We used a combination of population dynamics and time series models to quantify individual stock trends as well as common temporal trends in pink and chum salmon productivity across local, regional, and continental spatial scales. Our results indicated widespread declines in productivity of wild chum salmon stocks throughout Washington (WA) and British Columbia (BC) with 81% of stocks showing recent declines in productivity, although the exact form of the trends varied among regions. For pink salmon, the majority of stocks in WA and BC (65%) did not have strong temporal trends in productivity; however, all stocks that did have trends in productivity showed declining productivity since at least brood year 1996. We found weaker evidence of widespread declines in productivity for Alaska pink and chum salmon, with some regions and stocks showing declines in productivity (e.g., Kodiak chum salmon stocks) and others showing increases (e.g., Alaska Peninsula pink salmon stocks). We also found strong positive covariation between stock productivity series at the regional spatial scale for both pink and chum salmon, along with evidence that this regional-scale positive covariation has become stronger since the early 1990s in WA and BC. In general, our results suggest that common processes operating at the regional or multi-regional spatial scales drive productivity of pink and chum salmon stocks in western North America and that the effects of these process on productivity may change over time. PMID:26760510

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

    Science.gov (United States)

    Mattingly, Kyle S.; Mote, Thomas L.

    2017-01-01

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

  13. Dietary intake and habits of South Asian immigrants living in Western countries.

    Science.gov (United States)

    LeCroy, Madison N; Stevens, June

    2017-06-01

    Previous reviews have indicated that immigration from South Asian to Western countries leads to unhealthy changes in diet; however, these reviews have been limited by the methods used in some included studies. This critical narrative review summarizes findings from original research articles that performed appropriate statistical analyses on diet data obtained using culturally appropriate diet assessment measures. All studies quantitatively compared the diets of South Asian immigrants with those of residents of Western or South Asian countries or with those of South Asian immigrants who had varying periods of time since immigration. Most studies examined total energy and nutrient intake among adults. Total energy intake tended to decrease with increasing duration of residence and immigrant generation, and immigrants consumed less protein and monounsaturated fat compared with Westerners. However, findings for intakes of carbohydrate, total fat, saturated fat, polyunsaturated fat, and micronutrients were mixed. Studies that examine food group intake and include South Asians living in South Asia as a comparison population are needed. © The Author(s) 2017. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  14. Gangnam-Style Plastic Surgery: The Science of Westernized Beauty in South Korea.

    Science.gov (United States)

    Leem, So Yeon

    2017-10-01

    New beauty ideals and particular types of plastic surgery beauty have emerged in South Korea from the early twenty-first century. By defining Gangnam-style plastic surgery as a hybrid of old Westernized beauty ideals and a new science of beauty with variations and contradictions, I intend to twist the simplistic understanding of non-Western plastic surgery as an effort to resemble the white westerner's body. I also draw political implications from a case of monstrous Gangnam-style beauty made by excessive plastic surgery.

  15. Genetic Differentiation within the Puccinia triticina Population in South America and Comparison with the North American Population Suggests Common Ancestry and Intercontinental Migration

    Science.gov (United States)

    Leaf rust, caused by Puccinia triticina is the most prevalent and widespread disease of wheat in South America. The objective of this study was to determine the number of genetically differentiated groups of P. triticina that are currently present in South America, and to compare the South American ...

  16. Summer precipitation variability over Southeastern South America in a global warming scenario

    Energy Technology Data Exchange (ETDEWEB)

    Junquas, C. [UPMC/CNRS, Laboratoire de Meteorologie Dynamique, Institut Pierre Simon Laplace, Ecole Polytechnique, Paris (France); UMI-IFAECI CNRS-CONICET-UBA, Centro de Investigaciones del Mar y la Atmosfera (CIMA), DCAO/FCEyN, Buenos Aires (Argentina); Vera, C. [UMI-IFAECI CNRS-CONICET-UBA, Centro de Investigaciones del Mar y la Atmosfera (CIMA), DCAO/FCEyN, Buenos Aires (Argentina); Li, L.; Le Treut, H. [UPMC/CNRS, Laboratoire de Meteorologie Dynamique, Institut Pierre Simon Laplace, Ecole Polytechnique, Paris (France)

    2012-05-15

    December-January-February (DJF) rainfall variability in southeastern South America (SESA) is studied in 18 coupled general circulation models from the WCRP/CMIP3 dataset, for present climate and the SRES-A1B climate change scenario. The analysis is made in terms of properties of the first leading pattern of rainfall variability in the region, characterized by a dipole-like structure with centers of action in the SESA and South Atlantic Convergence Zone (SACZ) regions. The study was performed to address two issues: how rainfall variability in SESA would change in a future climate and how much of that change explains the projected increasing trends in the summer mean rainfall in SESA identified in previous works. Positive (negative) dipole events were identified as those DJF seasons with above (below) normal rainfall in SESA and below (above) normal rainfall in the SACZ region. Results obtained from the multi-model ensemble confirm that future rainfall variability in SESA has a strong projection on the changes of seasonal dipole pattern activity, associated with an increase of the frequency of the positive phase. In addition, the frequency increase of positive dipole phase in the twenty first century seems to be associated with an increase of both frequency and intensity of positive SST anomalies in the equatorial Pacific, and with a Rossby wave train-like anomaly pattern linking that ocean basin to South America, which regionally induces favorable conditions for moisture transport convergence and rainfall increase in SESA. (orig.)

  17. Climate change and American Bullfrog invasion: what could we expect in South America?

    Directory of Open Access Journals (Sweden)

    Javier Nori

    Full Text Available BACKGROUND: Biological invasion and climate change pose challenges to biodiversity conservation in the 21(st century. Invasive species modify ecosystem structure and functioning and climatic changes are likely to produce invasive species' range shifts pushing some populations into protected areas. The American Bullfrog (Lithobates catesbeianus is one of the hundred worst invasive species in the world. Native from the southeast of USA, it has colonized more than 75% of South America where it has been reported as a highly effective predator, competitor and vector of amphibian diseases. METHODOLOGY/PRINCIPAL FINDINGS: We modeled the potential distribution of the bullfrog in its native range based on different climate models and green-house gases emission scenarios, and projected the results onto South America for the years of 2050 and 2080. We also overlaid projected models onto the South American network of protected areas. Our results indicate a slight decrease in potential suitable area for bullfrog invasion, although protected areas will become more climatically suitable. Therefore, invasion of these sites is forecasted. CONCLUSION/SIGNIFICANCE: We provide new evidence supporting the vulnerability of the Atlantic Forest Biodiversity Hotspot to bullfrog invasion and call attention to optimal future climatic conditions of the Andean-Patagonian forest, eastern Paraguay, and northwestern Bolivia, where invasive populations have not been found yet. We recommend several management and policy strategies to control bullfrog invasion and argue that these would be possible if based on appropriate articulation among government agencies, NGOs, research institutions and civil society.

  18. Fire Ants (Solenopsis spp. and Their Natural Enemies in Southern South America

    Directory of Open Access Journals (Sweden)

    Juan Briano

    2012-01-01

    Full Text Available We review the fire ant research conducted by the ARS-South American Biological Control Laboratory (SABCL since 1987 to find a complex of natural enemies in southern South America and evaluate their specificity and suitability for field release as self-sustaining biological control agents. We also include those studies conducted by the ARS-Center for Medical, Agriculture, and Veterinary Entomology in the United States with the SABCL collaboration. Ecological and biological information is reported on local fire ants and their microsporidia, nematodes, viruses, phorid flies, eucharitid wasps, strepsiptera, and parasitic ants. Their biology, abundance, distribution, detrimental effect, field persistence, specificity, and phenology are discussed. We conclude that the objectives of the ARS program in South America are being achieved and that the pioneering studies have served to encourage further investigations in the United States and other countries and advanced the implementation of biological control programs to decrease imported fire ant densities and damage. Still, several promising organisms should be further investigated for eventual field release in the near future.

  19. Antimicrobial resistance among Enterobacteriaceae in South America: history, current dissemination status and associated socioeconomic factors.

    Science.gov (United States)

    Bonelli, Raquel Regina; Moreira, Beatriz Meurer; Picão, Renata Cristina

    2014-04-01

    South America exhibits some of the higher rates of antimicrobial resistance in Enterobactericeae worldwide. This continent includes 12 independent countries with huge socioeconomic differences, where the ample access to antimicrobials, including counterfeit ones, coexists with ineffective health systems and sanitation problems, favoring the emergence and dissemination of resistant strains. This work presents a literature review concerning the evolution and current status of antimicrobial resistance threats found among Enterobacteriaceae in South America. Resistance to β-lactams, fluoroquinolones and aminoglycosides was emphasized along with description of key epidemiological studies that highlight the success of specific resistance determinants in different parts of the continent. In addition, a discussion regarding political and socioeconomic factors possibly related to the dissemination of antimicrobial resistant strains in clinical settings and at the community is presented. Finally, in order to assess the possible sources of resistant bacteria, we compile the current knowledge about the occurrence of antimicrobial resistance in isolates in South American' food, food-producing animals and off-hospitals environments. By addressing that intensive intercontinental commerce and tourism neutralizes the protective effect of geographic barriers, we provide arguments reinforcing that globally integrated efforts are needed to decelerate the emergence and dissemination of antimicrobial resistant strains. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Going like gangbusters: transnational tobacco companies "making a killing" in South America.

    Science.gov (United States)

    Stebbins, K R

    2001-06-01

    This article reports on the recent growth of transnational tobacco companies (TTCs) in South America. Although some scholarly attention has been directed toward such growth in Asia and eastern Europe, South America has also been targeted by the TTCs' aggressive expansionist practices in recent years. Fighting "Big Tobacco" is entirely different from combating most public health problems. Unlike cigarettes, most infectious diseases and maternal and child health problems never provide profits to transnational corporations and governments. Also, most public health problems (with alcohol being another notable exception) are not exacerbated by extensive advertising campaigns that promote the cause of the health problems. Supported by data gathered during three months of fieldwork in Ecuador, Peru, Chile, and Argentina in 1997, this article suggests that the TTCs' marketing strategies override cultural differences in the choices people make regarding smoking and health. Combining critical medical anthropology and public health, this article concludes that unless dramatic actions are taken, an avoidable outbreak of tobacco-related diseases will eventually reach epidemic proportions on the South American continent. It is also a "call to arms" for more medical anthropologists to investigate tobacco-related matters around the world.

  1. The collision of rights and its impact on access to essential medicines: Challenges for South America

    Directory of Open Access Journals (Sweden)

    Raúl Allard Soto

    2018-05-01

    Full Text Available The collision between intellectual property rights and the right to health due to obligations assumed simultaneously –the WTO trips Agreement and the United Nations International Covenant on Economic, Social and Cultural Rights– by the twelve countries of South America, has had a profound impact regarding their populations access to essential medicines. The paper reports this situation in the region, while placing it in the context of the debate on trade and human rights, which has been particularly strong since the beginning of this century in the field of public health. The need for South American countries to strengthen intraregional cooperation as well as the promotion of South-South cooperation in access to essential medicines, taking into account the prevalence of pharmaceutical patents held by private laboratories in the northern hemisphere, is underlined. The advances made in this direction by the South American Health Council of Unasur, together with its actions as a regional bloc at the WTO meetings, are promising steps that must be complemented by the development of joint drug production capabilities.

  2. Oxygen isotope records of Globigerina bulloides across a north-south transect in the south-western Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Khare, N.; Chaturvedi, S.K.; Saraswat, R

    , Washington, D.C). Lutjeharms, J.R.E., N.M. Walters and B.R. Allanson. 1985. Oceanic frontal systems and biologicalenhancement. p.11-21. In: Antarctic Nutrient Cycles and Food Webs. ed. by W.R. Siegfried et al., Springer-Verlag, NewYork. Matsumoto, K., J...: Ocean Sci. J.: 44(2); 2009; 117-123 OXYGEN ISOTOPE RECORDS OF GLOBIGERINA BULLOIDES ACROSS A NORTH-SOUTH TRANSECT IN THE SOUTH-WESTERN INDIAN OCEAN N. Khare 1* , S. K. Chaturvedi 2 and R. Saraswat 3 1. Ministry of Earth Sciences, Block...

  3. The first peopling of South America: new evidence from Y-chromosome haplogroup Q.

    Science.gov (United States)

    Battaglia, Vincenza; Grugni, Viola; Perego, Ugo Alessandro; Angerhofer, Norman; Gomez-Palmieri, J Edgar; Woodward, Scott Ray; Achilli, Alessandro; Myres, Natalie; Torroni, Antonio; Semino, Ornella

    2013-01-01

    Recent progress in the phylogenetic resolution of the Y-chromosome phylogeny permits the male demographic dynamics and migratory events that occurred in Central and Southern America after the initial human spread into the Americas to be investigated at the regional level. To delve further into this issue, we examined more than 400 Native American Y chromosomes (collected in the region ranging from Mexico to South America) belonging to haplogroup Q - virtually the only branch of the Y phylogeny observed in modern-day Amerindians of Central and South America - together with 27 from Mongolia and Kamchatka. Two main founding lineages, Q1a3a1a-M3 and Q1a3a1-L54(xM3), were detected along with novel sub-clades of younger age and more restricted geographic distributions. The first was also observed in Far East Asia while no Q1a3a1-L54(xM3) Y chromosome was found in Asia except the southern Siberian-specific sub-clade Q1a3a1c-L330. Our data not only confirm a southern Siberian origin of ancestral populations that gave rise to Paleo-Indians and the differentiation of both Native American Q founding lineages in Beringia, but support their concomitant arrival in Mesoamerica, where Mexico acted as recipient for the first wave of migration, followed by a rapid southward migration, along the Pacific coast, into the Andean region. Although Q1a3a1a-M3 and Q1a3a1-L54(xM3) display overlapping general distributions, they show different patterns of evolution in the Mexican plateau and the Andean area, which can be explained by local differentiations due to demographic events triggered by the introduction of agriculture and associated with the flourishing of the Great Empires.

  4. Romantic Experiences of Homeland and Diaspora South Asian Youth: Westernizing Processes of Media and Friends

    Science.gov (United States)

    Dhariwal, Amrit; Connolly, Jennifer

    2013-01-01

    The current study examined 1316 South Asian youth socialized in progressively Westernized contexts: "traditional" Indian homeland single-sex schools, "transitional" Indian homeland co-educational schools, and the immigrant "diaspora" in Canadian schools. Results showed youth in the three contexts were similar on…

  5. Cervical HPV natural history among young Western Cape, South African women: The randomized control EVRI Trial

    NARCIS (Netherlands)

    Sudenga, Staci L.; Torres, B. Nelson; Botha, Matthys H.; Zeier, Michele; Abrahamsen, Martha E.; Glashoff, Richard H.; Engelbrecht, Susan; Schim van der Loeff, Maarten F.; van der Laan, Louvina E.; Kipping, Siegfried; Taylor, Douglas; Giuliano, Anna R.

    2016-01-01

    The objective of this analysis was to assess human papillomavirus (HPV) infection persistence and incidence 7-months post-enrollment by HPV vaccine study arm (vaccine or placebo). HIV-negative, sexually active women aged 16-24 years in the Western Cape, South Africa, were enrolled in the EVRI Trial

  6. Predictors of Mortality in a Critical Care Unit in South Western Kenya

    African Journals Online (AJOL)

    Abstract. Background: Critical care in developing countries has been ... which may impact the quality of care. Hospitals also ... and referral facility located in South Western Kenya in Bomet .... p=0.01). As regards end of life care; 40.4% of those.

  7. Description of a new moss frog from the south-western Cape (Anura ...

    African Journals Online (AJOL)

    A new species of moss frog, genus Arthroleptella, is described from the Kleinrivier mountains of the south-western Cape. It is morphologically indistinguishable from the other three species in the area. The four Cape species are allopatric, each has a unique male advertisement call, and preliminary molecular data shows ...

  8. How do we know how much groundwater is stored in south-western Cape mountains?

    CSIR Research Space (South Africa)

    Midgley, JJ

    2001-07-01

    Full Text Available Isotopes of water (D, O-18) in rain and streams were used to obtain an estimate of the amount of ground water in the south-western Cape Mountains. It was assumed that the groundwater reservoir is well-mixed and that the water isotope signals...

  9. HIV/AIDS: Knowledge and attitudes of dentists in South-Western ...

    African Journals Online (AJOL)

    Objective: The purpose of this study was to assess the knowledge and attitudes of dentists in South-Western Nigeria in relation to HIV/AIDS. Materials and methods: A questionnaire survey of 164 dentists in Lagos, Ibadan and Benin The data was analyzed using Epi-info statistical software. Results: The modes of ...

  10. The birds of the alien Acacia thickets of the South-western Cape

    African Journals Online (AJOL)

    About 1876, the Cape Superintendent of Plantations began using the Australian Acacia cyanophylla and A. ... Strandveld; but 38 % of all nests recorded in the South-western Cape are in Acacia. S. senegalensis is .... of mixed exotic trees, often including some Acacia but also Eucalyptus, Pinus, Quercus,. Populus and other ...

  11. Principals' Leadership Skills and School Effectiveness: The Case of South Western Nigeria

    Science.gov (United States)

    Bolanle, Akinola Oluwatoyin

    2013-01-01

    The study sought to find out the leadership skills possessed by Principals of public secondary schools in south western Nigeria and the relationship between these leadership skills and school effectiveness in terms of student academic achievement. The descriptive survey research design was employed for the study. 154 Principals and 770 teachers,…

  12. Education and Countering Violent Extremism: Western Logics from South to North?

    Science.gov (United States)

    Novelli, Mario

    2017-01-01

    This paper explores the way education and conflict have become entangled during the post-9/11 "war on terror" response to "radical Islam" at home and abroad. The paper charts the complex ways that education has been deployed to serve Western military and security objectives in multiple locations in the global south and how…

  13. Syntaxonomy and zonation patterns in coastal salt marshes of the Uilkraals Estuary, Western Cape (South Africa)

    NARCIS (Netherlands)

    Mucina, L.; Janssen, J.A.M.; O'Callaghan, M.

    2003-01-01

    Vegetation on salt marshes of the Uilkraals Estuary (near Gansbaai, Western Cape, South Africa) is described and classified into 11 associations and/or rank-less plant communities (further subdivided into a number of sub-units). These communities were grouped into 6 high-rank syntaxa (alliances and

  14. South Indian "Solkattu" and Western Music Pedagogy: Creating New Rhythmic Perspectives

    Science.gov (United States)

    Wood, Brandon Keith

    2013-01-01

    Part of the classical music tradition of South India, "solkattu" reinforces the statement "If you can say it, you can play it." This system of percussive syllables can help young musicians approach rhythm training in a way not usually available to students in Western countries. This article offers applications for a music…

  15. Non-metropolitan residential gated developments in the Western Cape Province, South Africa

    CSIR Research Space (South Africa)

    Spocter, M

    2011-07-01

    Full Text Available -metropolitan locale and the topic is also unexplored in the South African context. This research attempts to address this research gap by investigating the locations of gated developments in non-metropolitan towns of varying sizes in the Western Cape...

  16. Multi-year GNSS monitoring of atmospheric IWV over Central and South America for climate studies

    Science.gov (United States)

    Mendoza, Luciano; Bianchi, Clara; Fernández, Laura; Natali, María Paula; Meza, Amalia; Moirano, Juan

    2017-04-01

    Atmospheric water vapour has been acknowledged as an essential climate variable. Weather prediction and hazard assessment systems benefit from real-time observations, whereas long-term records contribute to climate studies. Nowadays, ground-based GNSS products have become widely employed, complementing satellite observations over the oceans. Although the past decade has seen a significant development of the GNSS infrastructure in Central and South America, its potential for atmospheric water vapour monitoring has not been fully exploited. With this in mind, we have performed a regional, seven-year long and homogeneous analysis, comprising 136 GNSS tracking stations, obtaining high-rate and continuous observations of column integrated water vapour and troposphere zenith total delay (Bianchi et al. 2016). As preliminary application for this data set, we have estimated local water vapour trends, their significance, and their relation with specific climate regimes. We have found evidence of drying at temperate regions in South America, at a rate of about 2% per decade, while a slow moistening of the troposphere over tropical regions is also weakly suggested by our results. Furthermore, we have assessed the regional performance of the empirical model GPT2w to blindly estimate troposphere delays. The model fairly reproduces the observed mean delays, including their annual and semi-annual variations. Nevertheless, a long-term evaluation has shown systematical biases, up to 20 mm, probably inherited form the underling atmospheric reanalysis. Additionally, the complete data set has been made openly available at a scientific repository (doi:10.1594/PANGAEA.858234). References: C. Bianchi, L. Mendoza, L. Fernandez, M. P. Natali, A. Meza, J. F. Moirano, Multi-year GNSS monitoring of atmospheric IWV over Central and South America for climate studies, Ann. Geophys., ISSN 0992-7689, eISSN 1432-0576, 34 (7), 623-639 (doi:10.5194/angeo-34-623-2016).

  17. Storm-time total electron content and its response to penetration electric fields over South America

    Directory of Open Access Journals (Sweden)

    P. M. de Siqueira

    2011-10-01

    Full Text Available In this work the response of the ionosphere due to the severe magnetic storm of 7–10 November 2004 is investigated by analyzing GPS Total Electron Content (TEC maps constructed for the South America sector. In order to verify the disturbed zonal electric fields in South America during the superstorm, ionospheric vertical drift data obtained from modeling results are used in the analysis. The vertical drifts were inferred from ΔH magnetometer data (Jicamarca-Piura following the methodology presented by Anderson et al. (2004. Also used were vertical drifts measured by the Jicamarca ISR. Data from a digisonde located at São Luís, Brazil (2.33° S, 44.2° W, dip latitude 0.25° are presented to complement the Jicamarca equatorial data. Penetration electric fields were observed by the comparison between the equatorial vertical drifts and the Interplanetary Electric Field (IEF. The TEC maps obtained from GPS data reflect the ionospheric response over the South America low-latitude and equatorial region. They reveal unexpected plasma distributions and TEC levels during the main phase of the superstorm on 7 November, which is coincident with the local post-sunset hours. At this time an increase in the pre-reversal enhancement was expected to develop the Equatorial Ionization Anomaly (EIA but we observed the absence of EIA. The results also reveal well known characteristics of the plasma distributions on 8, 9, and 10 November. The emphasized features are the expansion and intensification of EIA due to prompt penetration electric fields on 9 November and the inhibition of EIA during post-sunset hours on 7, 8, and 10 November. One important result is that the TEC maps provided a bi-dimensional view of the ionospheric changes offering a spatial description of the electrodynamics involved, which is an advantage over TEC measured by isolated GPS receivers.

  18. Linking the basement geology along the Africa-South America coasts in the South Atlantic

    Czech Academy of Sciences Publication Activity Database

    Konopásek, J.; Sláma, Jiří; Košler, J.

    2016-01-01

    Roč. 280, July (2016), s. 221-230 ISSN 0301-9268 Institutional support: RVO:67985831 Keywords : Gondwana reconstruction * South Atlantic Ocean * Plate tectonics * Kaoko Belt * Dom Feliciano Belt Subject RIV: DB - Geology ; Mineralogy Impact factor: 3.843, year: 2016

  19. An alternative model for the early peopling of southern South America revealed by analyses of three mitochondrial DNA haplogroups.

    Science.gov (United States)

    de Saint Pierre, Michelle; Bravi, Claudio M; Motti, Josefina M B; Fuku, Noriyuki; Tanaka, Masashi; Llop, Elena; Bonatto, Sandro L; Moraga, Mauricio

    2012-01-01

    After several years of research, there is now a consensus that America was populated from Asia through Beringia, probably at the end of the Pleistocene. But many details such as the timing, route(s), and origin of the first settlers remain uncertain. In the last decade genetic evidence has taken on a major role in elucidating the peopling of the Americas. To study the early peopling of South America, we sequenced the control region of mitochondrial DNA from 300 individuals belonging to indigenous populations of Chile and Argentina, and also obtained seven complete mitochondrial DNA sequences. We identified two novel mtDNA monophyletic clades, preliminarily designated B2l and C1b13, which together with the recently described D1g sub-haplogroup have locally high frequencies and are basically restricted to populations from the extreme south of South America. The estimated ages of D1g and B2l, about ~15,000 years BP, together with their similar population dynamics and the high haplotype diversity shown by the networks, suggests that they probably appeared soon after the arrival of the first settlers and agrees with the dating of the earliest archaeological sites in South America (Monte Verde, Chile, 14,500 BP). One further sub-haplogroup, D4h3a5, appears to be restricted to Fuegian-Patagonian populations and reinforces our hypothesis of the continuity of the current Patagonian populations with the initial founders. Our results indicate that the extant native populations inhabiting South Chile and Argentina are a group which had a common origin, and suggest a population break between the extreme south of South America and the more northern part of the continent. Thus the early colonization process was not just an expansion from north to south, but also included movements across the Andes.

  20. Effects of projected climate (2011–50) on karst hydrology and species vulnerability—Edwards aquifer, south-central Texas, and Madison aquifer, western South Dakota

    Science.gov (United States)

    Mahler, Barbara J.; Stamm, John F.; Poteet, Mary F.; Symstad, Amy J.; Musgrove, MaryLynn; Long, Andrew J.; Norton, Parker A.

    2015-12-22

    Karst aquifers—formed by the dissolution of soluble rocks such as limestone—are critical groundwater resources in North America, and karst springs, caves, and streams provide habitat for unique flora and fauna. Springflow and groundwater levels in karst terrane can change greatly over short time scales, and therefore are likely to respond rapidly to climate change. How might the biological communities and ecosystems associated with karst respond to climate change and accompanying changes in groundwater levels and springflow? Sites in two central U.S. regions—the Balcones Escarpment of south-central Texas and the Black Hills of western South Dakota (fig. 1)—were selected to study climate change and its potential effects on the local karst hydrology and ecosystem. The ecosystems associated with the Edwards aquifer (Balcones Escarpment region) and Madison aquifer (Black Hills region) support federally listed endangered and threatened species and numerous State-listed species of concern, including amphibians, birds, insects, and plants. Full results are provided in Stamm and others (2014), and are summarized in this fact sheet.

  1. Cornerstones of a renewable energy law for emerging markets in South America

    Energy Technology Data Exchange (ETDEWEB)

    Kissel, Johannes M. [Department of Renewable Energies, Institute for Energy and Control Technology, Technical University Berlin (TUB), Sec. EM 4, Einsteinufer 11, D-10587 Berlin (Germany); Instituto IDEAL (World Council for Renewable Energy, Latin America), Rua Lauro Linhares, 2123 Torre A Sala 503, Trindade, CEP 88036-003/SC, Florianopolis (Brazil); Hanitsch, Rolf [Department of Renewable Energies, Institute for Energy and Control Technology, Technical University Berlin (TUB), Sec. EM 4, Einsteinufer 11, D-10587 Berlin (Germany); PI Photovoltaik-Institut Berlin AG, Module Technology: Testing, Consulting, Research, Einsteinufer 25, D-10587 Berlin (Germany); Krauter, Stefan C.W. [Department of Renewable Energies, Institute for Energy and Control Technology, Technical University Berlin (TUB), Sec. EM 4, Einsteinufer 11, D-10587 Berlin (Germany); PI Photovoltaik-Institut Berlin AG, Module Technology: Testing, Consulting, Research, Einsteinufer 25, D-10587 Berlin (Germany); Biberach University of Applied Sciences, P.O. Box 1260, 88382 Biberach (Germany)

    2009-09-15

    Since 1990, effective support schemes for renewable energies have been introduced mainly in European countries. In this article, the authors explain which consequences different general conditions could have on the design and functioning of feed-in laws. Cornerstones for an adjusted feed-in law to the particular general conditions of emerging and developing countries in South America will be drawn, which should give support to the decision-makers for designing an attuned and well-functioning feed-in legislation. (author)

  2. Drevnyaya astronomiya Yuzhnoj Ameriki %t Ancient astronomy of the South America

    Science.gov (United States)

    Yurevich, V. A.

    The article portrays our knowledge of the astronomy of the South America before its discovery by European. The archeoastronomical monuments display that the astronomy was the basis for the calendar, and its probable reconstruction is proposed. The author demonstrated that all solar and moon directions of the horizon astronomy were used in it. First chronicles and ethnographic data give information about the cosmological ideas of native-Americans, their worships of the celestial objects (the Sun, Moon), implication of astronomical phenomena in their religious rituals and feasts.

  3. Radon in groundwaters from Guarany aquifer, South America: environmental and exploration implications

    International Nuclear Information System (INIS)

    Bonotto, D.M.; Caprioglio, L.

    2002-01-01

    Groundwater and sandstone samples were analyzed for radon in Guarany aquifer, Parana sedimentary basin, South America. The dissolved radon ranged between 3 and 3303 pCi/l, being lognormally distributed, with a modal value of 1315 pCi/l, and a median value of 330 pCi/l. 222 Rn leakage experiments for sandstones yielded a theoretical value of 1390 pCi/l for 222 Rn in water, showing that theoretical modeling can reliably be used to interpret laboratory and field data

  4. COELIAC DISEASE IN CENTRAL AND SOUTH AMERICA: time for a concerted approach to its epidemiology

    Directory of Open Access Journals (Sweden)

    Affifa FARRUKH

    2015-06-01

    Full Text Available Central and South America offer an opportunity to resolve some of the current controversies that surround the epidemiology of celiac disease. Through a concerted action which brings together clinicians, researchers and patients there is an opportunity to establish robust data sets which will allow detailed analysis of environmental and genetic factors. In this review available data from the continent together with data from Spain and Italy are drawn together to give a current picture in the hope that it will stimulate further research.

  5. Monotypic no longer: a new species of Panca Evans (Lepidoptera: Hesperiidae: Hesperiinae: Moncini) from South America.

    Science.gov (United States)

    Dolibaina, Diego Rodrigo; Carneiro, Eduardo; Mielke, Olaf Hermann Hendrik; Casagrande, Mirna Martins; Lamas, Gerardo

    2017-05-19

    A new species belonging to the previously monotypic genus Panca Evans, 1955, P. moseri Dolibaina, Carneiro & O. Mielke sp. nov., from grasslands areas of Peru, Bolivia and Brazil is described. Adults and male and female genitalia of the new species are illustrated, described in detail, and compared with the type species of the genus, Lerodea subpunctuli Hayward, 1934, and with its externally most similar and sympatric species, Vidius mictra Evans, 1955. The systematic position of the genus Panca and its association with lowland open natural habitats of South America are discussed.

  6. Rearming and Low Perception of International Threat in South America: Is that Coexistence Possible?

    Directory of Open Access Journals (Sweden)

    Jorge M. Battaglino

    2010-01-01

    Full Text Available The purpose of this article is to critically analyze the use of the concept of rearmament to explain the purchases of arms in South America. The use of this term has not only contributed to the conceptual confusion but also to a risky political use of it. The concept rearmament has a specific historical meaning which is often link to situations of acute perceptions of threat among states and to the imminent break of war. From a theoretical and empirical perspective, neither the historical understanding of the concept nor its empirical referents are present in the region.

  7. Maintenance of Austral Summertime Upper-Tropospheric Circulation over Tropical South America: The Bolivian High-Nordeste Low System.

    Science.gov (United States)

    Chen, Tsing-Chang; Weng, Shu-Ping; Schubert, Siegfried

    1999-07-01

    Using the NASA/GEOS reanalysis data for 1980-95, the austral-summer stationary eddies in the tropical-subtropical Southern Hemisphere are examined in two wave regimes: long and short wave (wave 1 and waves 2-6, respectively). The basic structure of the Bolivian high-Nordeste low (BH-NL) system is formed by a short-wave train across South America but modulated by the long-wave regime. The short-wave train exhibits a monsoonlike vertical phase reversal in the midtroposphere and a quarter-wave phase shift relative to the divergent circulation. As inferred from (a) the spatial relationship between the streamfunction and velocity potential and (b) the structure of the divergent circulation, the short-wave train forming the BH-NL system is maintained by South American local heating and remote African heating, while the long-wave regime is maintained by western tropical Pacific heating.The maintenance of the stationary waves in the two wave regimes is further illustrated by a simple diagnostic scheme that includes the velocity-potential maintenance equation (which links velocity potential and diabatic heating) and the streamfunction budget (which is the inverse Laplacian transform of the vorticity equation). Some simple relationships between streamfunction and velocity potential for both wave regimes are established to substantiate the links between diabatic heating and streamfunction; of particular interest is a Sverdrup balance in the short-wave regime. This simplified vorticity equation explains the vertical structure of the short-wave train associated with the BH-NL system and its spatial relationship with the divergent circulation.Based upon the diagnostic analysis of its maintenance a simple forced barotropic model is adopted to simulate the BH-NL system with idealized forcings, which imitates the real 200-mb divergence centers over South America, Africa, and the tropical Pacific. Numerical simulations demonstrate that the formation of the BH-NL system is affected

  8. Study physico-chemical of the sand of the western ERG (Western South Algeria)

    Energy Technology Data Exchange (ETDEWEB)

    Allam, M.; Tafraoui, A. [Faculty of sciences and technology, University of Bechar (Algeria)], email: allammessaouda@yahoo.fr

    2011-07-01

    Silica is gaining increasing importance as it is the base for the production of pure silicon, for which several applications are under development in the electronic and solar energy sectors. The aim of this study is to characterize the sand taken from the Western Erg of Algeria to determine the percentage of silicon it contains. Characterization was done through physical analysis to determine the granulometry of the sand. A chemical analysis was next performed, using diffraction of X-rays and a scanning electron microscope to determine the chemical composition of the sand. Results showed that the sand is mainly made of quartz in the form of rounded and subbarrondis grains and that silicon is prevalent, accounting for 98% of the composition. This study demonstrated that sand from the Western Erg of Algeria is rich in silicon and could be used for silicon production.

  9. Radioactive mineral potential of carbonatites in western parts of the South American shields

    International Nuclear Information System (INIS)

    Premoli, C.; Kroonenberg, S.B.

    1984-01-01

    During the last eight years at least six carbonatites or clusters of carbonatites have been discovered in the western parts of the South American cratons. In contrast to the carbonatites of the eastern part of the South American shields, which have been well studied and placed in a tectonic context together with the West African carbonatite provinces, those of the western part of the South American cratons have received litte attention. This paper is a compilation of published and original data on these occurrences, their geology, geochemistry, structural setting and radioactive mineral potential. An exploration strategy is devised based on experiences in this rainforest-clad area and the peculiar genetic aspect of carbonatites. Some details of a possibly new uranium mineral encountered in Cerro Cora carbonatite are given. (author)

  10. [Tobacco advertisement exposure and tobacco consumption among youths in South America].

    Science.gov (United States)

    Plamondon, Geneviève; Guindon, G Emmanuel; Paraje, Guillermo

    2017-01-01

    To assesses the statistical association between exposure to tobacco marketing and tobacco consumption among adolescents in South America, by using data from the Global Youth Tobacco Survey. Using data from the Global Youth Tobacco Survey (GYTS), the exposure to tobacco marketing at the school level was studied from advertising in TV, radio, massive public events and street advertisement. Tobacco behaviour was considered. The total pooled sample used was 134 073 youths from Argentina, Bolivia, Chile, Peru, Brazil, Uruguay, Suriname, Colombia, Guyana, Ecuador, Paraguay and Venezuela. The exposure to tobacco marketing is positively and significantly associated to the probability of youths experimenting with tobacco (at least once in their lifetime). For regular smokers, exposure to tobacco marketing is positively and significantly associated to smoking intensity. These results call for the implementation of strong restrictions on tobacco advertisement of various types in South American countries.

  11. Tobacco advertisement exposure and tobacco consumption among youths in South America

    Directory of Open Access Journals (Sweden)

    Geneviéve Plamondon

    2017-03-01

    Full Text Available Objective. To assesses the statistical association between exposure to tobacco marketing and tobacco consumption among adolescents in South America, by using data from the Global Youth Tobacco Survey. Materials and methods. Using data from the Global Youth Tobacco Survey (GYTS, the exposure to tobacco marketing at the school level was studied from advertising in TV, radio, massive public events and street advertisement. Tobacco behaviour was considered. The total pooled sample used was 134 073 youths from Argentina, Bolivia, Chile, Peru, Brazil, Uruguay, Suriname, Colombia, Guyana, Ecuador, Paraguay and Venezuela. Results. The exposure to tobacco marketing is positively and significantly associated to the probability of youths experimenting with tobacco (at least once in their lifetime. For regular smokers, exposure to tobacco marketing is positively and significantly associated to smoking intensity. Conclusions. These results call for the implementation of strong restrictions on tobacco advertisement of various types in South American countries.

  12. Marine biodiversity in the Atlantic and Pacific coasts of South America: knowledge and gaps.

    Science.gov (United States)

    Miloslavich, Patricia; Klein, Eduardo; Díaz, Juan M; Hernández, Cristián E; Bigatti, Gregorio; Campos, Lucia; Artigas, Felipe; Castillo, Julio; Penchaszadeh, Pablo E; Neill, Paula E; Carranza, Alvar; Retana, María V; Díaz de Astarloa, Juan M; Lewis, Mirtha; Yorio, Pablo; Piriz, María L; Rodríguez, Diego; Yoneshigue-Valentin, Yocie; Gamboa, Luiz; Martín, Alberto

    2011-01-31

    The marine areas of South America (SA) include almost 30,000 km of coastline and encompass three different oceanic domains--the Caribbean, the Pacific, and the Atlantic--ranging in latitude from 12∘N to 55∘S. The 10 countries that border these coasts have different research capabilities and taxonomic traditions that affect taxonomic knowledge. This paper analyzes the status of knowledge of marine biodiversity in five subregions along the Atlantic and Pacific coasts of South America (SA): the Tropical East Pacific, the Humboldt Current,the Patagonian Shelf, the Brazilian Shelves, and the Tropical West Atlantic, and it provides a review of ecosystem threats and regional marine conservation strategies. South American marine biodiversity is least well known in the tropical subregions (with the exception of Costa Rica and Panama). Differences in total biodiversity were observed between the Atlantic and Pacific oceans at the same latitude. In the north of the continent, the Tropical East Pacific is richer in species than the Tropical West Atlantic, however, when standardized by coastal length, there is very little difference among them. In the south, the Humboldt Current system is much richer than the Patagonian Shelf. An analysis of endemism shows that 75% of the species are reported within only one of the SA regions, while about 22% of the species of SA are not reported elsewhere in the world. National and regional initiatives focusing on new exploration, especially to unknown areas and ecosystems, as well as collaboration among countries are fundamental to achieving the goal of completing inventories of species diversity and distribution.These inventories will allow accurate interpretation of the biogeography of its two oceanic coasts and latitudinal trends,and will also provide relevant information for science based policies.

  13. Fish and aquatic habitat conservation in South America: a continental overview with emphasis on neotropical systems.

    Science.gov (United States)

    Barletta, M; Jaureguizar, A J; Baigun, C; Fontoura, N F; Agostinho, A A; Almeida-Val, V M F; Val, A L; Torres, R A; Jimenes-Segura, L F; Giarrizzo, T; Fabré, N N; Batista, V S; Lasso, C; Taphorn, D C; Costa, M F; Chaves, P T; Vieira, J P; Corrêa, M F M

    2010-06-01

    Fish conservation in South America is a pressing issue. The biodiversity of fishes, just as with all other groups of plants and animals, is far from fully known. Continuing habitat loss may result in biodiversity losses before full species diversity is known. In this review, the main river basins of South America (Magdalena, Orinoco, Amazon and Paraná-La Plata system), together with key aquatic habitats (mangrove-fringed estuaries of the tropical humid, tropical semi-arid and subtropical regions) are analysed in terms of their characteristics and main concerns. Habitat loss was the main concern identified for all South American ecosystems. It may be caused by damming of rivers, deforestation, water pollution, mining, poor agricultural practice or inadequate management practice. Habitat loss has a direct consequence, which is a decrease in the availability of living resources, a serious social and economic issue, especially for South American nations which are all developing countries. The introduction of exotic species and overfishing were also identified as widespread across the continent and its main freshwater, coastal and marine ecosystems. Finally, suggestions are made to find ways to overcome these problems. The main suggestion is a change of paradigm and a new design for conservation actions, starting with integrated research and aiming at the co-ordinated and harmonized management of the main transboundary waters of the continent. The actions would be focused on habitat conservation and social rescue of the less well-off populations of indigenous and non-indigenous peoples. Energy and freshwater demands will also have to be rescaled in order to control habitat loss.

  14. Land cover characterization and mapping of South America for the year 2010 using Landsat 30 m satellite data

    Science.gov (United States)

    Giri, Chandra; Long, Jordan

    2014-01-01

    Detailed and accurate land cover and land cover change information is needed for South America because the continent is in constant flux, experiencing some of the highest rates of land cover change and forest loss in the world. The land cover data available for the entire continent are too coarse (250 m to 1 km) for resource managers, government and non-government organizations, and Earth scientists to develop conservation strategies, formulate resource management options, and monitor land cover dynamics. We used Landsat 30 m satellite data of 2010 and prepared the land cover database of South America using state-of-the-science remote sensing techniques. We produced regionally consistent and locally relevant land cover information by processing a large volume of data covering the entire continent. Our analysis revealed that in 2010, 50% of South America was covered by forests, 2.5% was covered by water, and 0.02% was covered by snow and ice. The percent forest area of South America varies from 9.5% in Uruguay to 96.5% in French Guiana. We used very high resolution (change database of South America with additional land cover classes is needed. The results from this study are useful for developing resource management strategies, formulating biodiversity conservation strategies, and regular land cover monitoring and forecasting.

  15. Changes in snowmelt runoff timing in western North America under a 'business as usual' climate change scenario

    Science.gov (United States)

    Stewart, I.T.; Cayan, D.R.; Dettinger, M.D.

    2004-01-01

    Spring snowmelt is the most important contribution of many rivers in western North America. If climate changes, this contribution may change. A shift in the timing of springtime snowmelt towards earlier in the year already is observed during 1948-2000 in many western rivers. Streamflow timing changes for the 1995-2099 period are projected using regression relations between observed streamflow-timing responses in each river, measured by the temporal centroid of streamflow (CT) each year, and local temperature (TI) and precipitation (PI) indices. Under 21st century warming trends predicted by the Parallel Climate Model (PCM) under business-as-usual greenhouse-gas emissions, streamflow timing trends across much of western North America suggest even earlier springtime snowmelt than observed to date. Projected CT changes are consistent with observed rates and directions of change during the past five decades, and are strongest in the Pacific Northwest, Sierra Nevada, and Rocky Mountains, where many rivers eventually run 30-40 days earlier. The modest PI changes projected by PCM yield minimal CT changes. The responses of CT to the simultaneous effects of projected TI and PI trends are dominated by the TI changes. Regression-based CT projections agree with those from physically-based simulations of rivers in the Pacific Northwest and Sierra Nevada.

  16. Genetic diversity and structure of western white pine (Pinus monticola) in North America: A baseline study for conservation, restoration, and addressing impacts of climate change

    Science.gov (United States)

    Mee-Sook Kim; Bryce A. Richardson; Geral I. McDonald; Ned B. Klopfenstein

    2010-01-01

    Western white pine (Pinus monticola) is an economically and ecologically important species in western North America that has declined in prominence over the past several decades, mainly due to the introduction of Cronartium ribicola (cause of white pine blister rust) and reduced opportunities for regeneration. Amplified fragment length polymorphism (AFLP) markers were...

  17. The first Oligocene sea turtle (Pan-Cheloniidae record of South America

    Directory of Open Access Journals (Sweden)

    Edwin Cadena

    2018-03-01

    Full Text Available The evolution and occurrence of fossil sea turtles at the Pacific margin of South America is poorly known and restricted to Neogene (Miocene/Pliocene findings from the Pisco Formation, Peru. Here we report and describe the first record of Oligocene (late Oligocene, ∼24 Ma Pan-Cheloniidae sea turtle remains of South America. The fossil material corresponds to a single, isolated and well-preserved costal bone found at the Montañita/Olón locality, Santa Elena Province, Ecuador. Comparisons with other Oligocene and extant representatives allow us to confirm that belongs to a sea turtle characterized by: lack of lateral ossification, allowing the dorsal exposure of the distal end of ribs; dorsal surface of bone sculptured, changing from dense vermiculation at the vertebral scute region to anastomosing pattern of grooves at the most lateral portion of the costal. This fossil finding shows the high potential that the Ecuadorian Oligocene outcrops have in order to explore the evolution and paleobiogeography distribution of sea turtles by the time that the Pacific and the Atlantic oceans were connected via the Panama basin.

  18. Environmental and Human Controls of Ecosystem Functional Diversity in Temperate South America

    Directory of Open Access Journals (Sweden)

    Domingo Alcaraz-Segura

    2013-01-01

    Full Text Available The regional controls of biodiversity patterns have been traditionally evaluated using structural and compositional components at the species level, but evaluation of the functional component at the ecosystem level is still scarce. During the last decades, the role of ecosystem functioning in management and conservation has increased. Our aim was to use satellite-derived Ecosystem Functional Types (EFTs, patches of the land-surface with similar carbon gain dynamics to characterize the regional patterns of ecosystem functional diversity and to evaluate the environmental and human controls that determine EFT richness across natural and human-modified systems in temperate South America. The EFT identification was based on three descriptors of carbon gain dynamics derived from seasonal curves of the MODIS Enhanced Vegetation Index (EVI: annual mean (surrogate of primary production, seasonal coefficient of variation (indicator of seasonality and date of maximum EVI (descriptor of phenology. As observed for species richness in the southern hemisphere, water availability, not energy, emerged as the main climatic driver of EFT richness in natural areas of temperate South America. In anthropogenic areas, the role of both water and energy decreased and increasing human intervention increased richness at low levels of human influence, but decreased richness at high levels of human influence.

  19. Unprecedented drought over tropical South America in 2016: significantly under-predicted by tropical SST.

    Science.gov (United States)

    Erfanian, Amir; Wang, Guiling; Fomenko, Lori

    2017-07-19

    Tropical and sub-tropical South America are highly susceptible to extreme droughts. Recent events include two droughts (2005 and 2010) exceeding the 100-year return value in the Amazon and recurrent extreme droughts in the Nordeste region, with profound eco-hydrological and socioeconomic impacts. In 2015-2016, both regions were hit by another drought. Here, we show that the severity of the 2015-2016 drought ("2016 drought" hereafter) is unprecedented based on multiple precipitation products (since 1900), satellite-derived data on terrestrial water storage (since 2002) and two vegetation indices (since 2004). The ecohydrological consequences from the 2016 drought are more severe and extensive than the 2005 and 2010 droughts. Empirical relationships between rainfall and sea surface temperatures (SSTs) over the tropical Pacific and Atlantic are used to assess the role of tropical oceanic variability in the observed precipitation anomalies. Our results indicate that warmer-than-usual SSTs in the Tropical Pacific (including El Niño events) and Atlantic were the main drivers of extreme droughts in South America, but are unable to explain the severity of the 2016 observed rainfall deficits for a substantial portion of the Amazonia and Nordeste regions. This strongly suggests potential contribution of non-oceanic factors (e.g., land cover change and CO2-induced warming) to the 2016 drought.

  20. Water vapour trends at several tropospheric levels over South America between 1973 and 2003

    International Nuclear Information System (INIS)

    Morales, L.; Mattar, C.; Da-Silva, L.; Abarca, R.

    2009-01-01

    In this paper water vapour trends were analyzed at several tropospheric levels over South America between 1973 and 2003. It was carried out using in situ values retrieved by 15 radiosonde stations and NCEP NCAR Reanalysis data (NNR). NNR and radiosonde water vapour data were linked to Koeppen-Geiger climatic zones to calculate anomalies, trends, and the non-parametric statistical significance for each mandatory level. A methodology used to process radiosonde data is shown. Water vapour trends in tropical climates presented positive decadal trends. This is statistically significant for the first mandatory levels retrieved by radiosonde. The highest values are presented in average with NNR; the decadal magnitude for climate Af being 0.15 g kg -1 for 1000 and 925 h Pa, and for climate As 0.27 g kg -1 for 925 and 850 h Pa. For non-tropical climates the magnitude trends of specific humidity are affected by the spatial resolution of NNR, which is seen when comparing the results received by the radiosondes. Finally, this paper shows the initial results of water vapour content trends in the last three decades over South America. Strong climatic events and synoptic oscillations were not commented upon.

  1. Measuring vulnerability to shocks in the gas market in South America

    International Nuclear Information System (INIS)

    Reymond, Mathias

    2012-01-01

    With a strong global demand for some 30 years, natural gas is a particular challenge for countries of South and Central America since each cubic meter of natural gas that is consumed is produced in this continent. It therefore seems appropriate to consider the risk of a collision gas and its effects on the countries most dependent on gas (either as producers or as consumers). Thus, in this paper, we study the vulnerability of gas in several countries on four ratios developed by Cabalu (2010). Once calculated from empirical data, these ratios helped to determine indicators and to classify countries according to their vulnerability in the event of a gas shock (sudden rise in prices). A picture emerges which represents an indicative classification of the countries. - Highlights: ► In this paper, we study the vulnerability of gas with four indicators. ► We focus on eight countries in South America and Central. ► These indicators helped to classify countries according to their vulnerability. ► The least vulnerable country is Bolivia. ► The most vulnerable countries are Chile and Venezuela.

  2. Hot continent: South America is open for fast growth in the natural gas sector

    International Nuclear Information System (INIS)

    Reinsch, A. E.

    1997-01-01

    Opportunities for participation in the rapid expansion of the natural gas sector in South America following privatization and deregulation initiatives, were examined on a country-by-country basis. In Colombia and Venezuela opportunities exist primarily in domestic development of the gas sector, whereas in the countries of the southern cone - Argentina, Bolivia, Brazil, Chile, Paraguay, Peru and Uruguay - the situation is said to be ripe for energy sector integration. Currently, a second regional pipeline link, with a capacity of 129 Bcf/year, is nearing completion, which will carry gas from west Argentina to Santiago, Chile, to supplement the 77 Bcf/year pipeline carrying gas from Bolivia to the Argentine border, where it connects with a trunk line to supply the Buenos Aires market. A Canadian Energy Research Institute study, to be published in the summer of 1997, focuses on the various pipeline links being put forward to integrate the gas resources in the southern cone with existing and potential gas markets. The integration scenarios examined are predicted to reveal both economic and commercial merit for the pipeline corridors. Canadian energy and pipeline companies are said to be well positioned to take advantage of the opportunities resulting from these initiatives, and to help making the vision of an integrated gas pipeline network in the southern cone of South America a reality

  3. The environmental paradox in generation: How South America is gradually becoming more dependent on thermal generation

    International Nuclear Information System (INIS)

    Arango, Santiago; Larsen, Erik R.

    2010-01-01

    There has been an increasing focus on global warming, emission of green house gases (GHG), and the problems this might create. In this article, we review the trend in sustainable and renewable electricity generation in South America, where the generation portfolio increasingly depends on thermal generation, in particular gas. South America is a region that has relatively low emissions, but the current development is not desirable in environmental terms. We analyze the underlying reasons for this development, which is related to security of supply, deregulation, and the cost of renewable energy. We review and discuss the policies to promote renewables in the region. We analyze the potential advantages and drawbacks of different types of market interventions, such as direct subsidies that create potentially strong market distortions, more sophisticated market interventions that might be less intrusive but not necessarily as effective as, e.g. firm energy markets. We also review market-based solutions such as the Clean Market Mechanism and its potential, and the use of renewable electricity in non-interconnected zones, which might be one of the most economically attractive applications of renewables. However, without a stronger and more aggressive intervention from the governments in the region it is unlikely that the increase in thermal generation can be stopped. (author)

  4. Mast fruiting is a frequent strategy in woody species of eastern South America.

    Directory of Open Access Journals (Sweden)

    Natalia Norden

    Full Text Available BACKGROUND: It is thought that mast seeding is a rare reproductive strategy in the tropics, since tropical climates are less variable, and fruit consumers tend to be more generalist in these regions. However, previous tests of this hypothesis were based on only few tropical datasets, and none from tropical South America. Moreover, reproductive strategies have been quantified based on the coefficient of variation of interannual seed production, an index that potentially confounds masting and high interannual variability in seed production. METHODOLOGY/PRINCIPAL FINDINGS: We developed a new approach to model the monthly variability in seed production for 28 tree species, and 20 liana species monitored during 5 years in a tropical forest of Central French Guiana. We found that 23% of the species showed a masting pattern, 54% an annual fruiting pattern, and 23% an irregular fruiting pattern. The majority of masting species were trees (8 out of 11, most of them animal-dispersed. The classification into reproductive strategies based on the coefficient of variation was inconsistent with our results in nearly half of the cases. CONCLUSIONS/SIGNIFICANCE: Our study is the first to clearly evidence the frequency of the masting strategy in a tropical forest community of Eastern South America. The commonness of the masting strategy in tropical plants may promote species coexistence through storage dynamics.

  5. [Infection by hepatitis virus among the indigenous populations of South America: a review of the problem].

    Science.gov (United States)

    Echevarría, J M; Blitz-Dorfman, L; Pujot, F H

    1996-09-01

    After the report of the epidemic outbreak of delta hepatitis among the Yukpa amerindians in the early 80s, the viral hepatitis arose as an important health problem in all the Amerindian communities from the north of South America and the Amazonian Basin. Despite the few data available, the results obtained in different communities from Venezuela (Yukpa, Barí, Yanomami) have shown a high endemicity of hepatitis B and D virus infections and a significant prevalence of hepatitis E virus-specific antibody among their members. By contrast, the infection by hepatitis C virus, which is present in all the urban areas from South America, seems uncommon, or even absent among some Amerindian populations. At the moment, a satisfactory explanation for this findings has not yet been arised. However, it could be possible that the margination of these populations regarding the health care system has been keeping them free of an infection largely linked worldwide to iatrogeny. Vaccination of Amerindian populations against hepatitis B should be taken as a priority of the health care programs. Moreover, such programs should consider the iatrogenic transmission of the HCV as a matter of concern regarding such populations, since parenterally transmitted hepatitis viruses seems to spread quickly among their members once they are introduced, giving rise to serious health problems.

  6. A diplodocid sauropod survivor from the early cretaceous of South America.

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    Pablo A Gallina

    Full Text Available Diplodocids are by far the most emblematic sauropod dinosaurs. They are part of Diplodocoidea, a vast clade whose other members are well-known from Jurassic and Cretaceous strata in Africa, Europe, North and South America. However, Diplodocids were never certainly recognized from the Cretaceous or in any other southern land mass besides Africa. Here we report a new sauropod, Leikupal laticauda gen. et sp. nov., from the early Lower Cretaceous (Bajada Colorada Formation of Neuquén Province, Patagonia, Argentina. This taxon differs from any other sauropod by the presence of anterior caudal transverse process extremely developed with lateroventral expansions reinforced by robust dorsal and ventral bars, very robust centroprezygapophyseal lamina in anterior caudal vertebra and paired pneumatic fossae on the postzygapophyses in anterior-most caudal vertebra. The phylogenetic analyses support its position not only within Diplodocidae but also as a member of Diplodocinae, clustering together with the African form Tornieria, pushing the origin of Diplodocoidea to the Middle Jurassic or even earlier. The new discovery represents the first record of a diplodocid for South America and the stratigraphically youngest record of this clade anywhere.

  7. Antimicrobial Activity and Chemical Composition of Essential Oils from Verbenaceae Species Growing in South America

    Directory of Open Access Journals (Sweden)

    Cristina M. Pérez Zamora

    2018-03-01

    Full Text Available The Verbenaceae family includes 2600 species grouped into 100 genera with a pantropical distribution. Many of them are important elements of the floras of warm-temperature and tropical regions of America. This family is known in folk medicine, and its species are used as digestive, carminative, antipyretic, antitussive, antiseptic, and healing agents. This review aims to collect information about the essential oils from the most reported species of the Verbenaceae family growing in South America, focusing on their chemical composition, antimicrobial activity, and synergism with commercial antimicrobials. The information gathered comprises the last twenty years of research within the South American region and is summarized taking into consideration the most representative species in terms of their essential oils. These species belong to Aloysia, Lantana, Lippia, Phyla, and Stachytarpheta genera, and the main essential oils they contain are monoterpenes and sesquiterpenes, such as β-caryophyllene, thymol, citral, 1,8-cineole, carvone, and limonene. These compounds have been found to possess antimicrobial activities. The synergism of these essential oils with antibiotics is being studied by several research groups. It constitutes a resource of interest for the potential use of combinations of essential oils and antibiotics in infection treatments.

  8. Mycobacterium tuberculosis strains of the Beijing genotype are rarely observed in tuberculosis patients in South America.

    Science.gov (United States)

    Ritacco, Viviana; López, Beatriz; Cafrune, Patricia I; Ferrazoli, Lucilaine; Suffys, Philip N; Candia, Norma; Vásquez, Lucy; Realpe, Teresa; Fernández, Jorge; Lima, Karla V; Zurita, Jeannete; Robledo, Jaime; Rossetti, Maria L; Kritski, Afranio L; Telles, Maria A; Palomino, Juan C; Heersma, Herre; van Soolingen, Dick; Kremer, Kristin; Barrera, Lucía

    2008-08-01

    The frequency of the Beijing genotype of Mycobacterium tuberculosis as a cause of tuberculosis (TB) in South America was determined by analyzing genotypes of strains isolated from patients that had been diagnosed with the disease between 1997 and 2003 in seven countries of the subcontinent. In total, 19 of the 1,202 (1.6%) TB cases carried Beijing isolates, including 11 of the 185 patients from Peru (5.9%), five of the 512 patients from Argentina (1.0%), two of the 252 Brazilian cases (0.8%), one of the 166 patients from Paraguay (0.6%) and none of the samples obtained from Chile (35), Colombia (36) and Ecuador (16). Except for two patients that were East Asian immigrants, all cases with Beijing strains were native South Americans. No association was found between carrying a strain with the Beijing genotype and having drug or multi-drug resistant disease. Our data show that presently transmission of M. tuberculosis strains of the Beijing genotype is not frequent in Latin America. In addition, the lack of association of drug resistant TB and infection with M. tuberculosis of the Beijing genotype observed presently demands efforts to define better the contribution of the virulence and lack of response to treatment to the growing spread of Beijing strains observed in other parts of the world.

  9. Mycobacterium tuberculosis strains of the Beijing genotype are rarely observed in tuberculosis patients in South America

    Directory of Open Access Journals (Sweden)

    Viviana Ritacco

    2008-08-01

    Full Text Available The frequency of the Beijing genotype of Mycobacterium tuberculosis as a cause of tuberculosis (TB in South America was determined by analyzing genotypes of strains isolated from patients that had been diagnosed with the disease between 1997 and 2003 in seven countries of the subcontinent. In total, 19 of the 1,202 (1.6% TB cases carried Beijing isolates, including 11 of the 185 patients from Peru (5.9%, five of the 512 patients from Argentina (1.0%, two of the 252 Brazilian cases (0.8%, one of the 166 patients from Paraguay (0.6% and none of the samples obtained from Chile (35, Colombia (36 and Ecuador (16. Except for two patients that were East Asian immigrants, all cases with Beijing strains were native South Americans. No association was found between carrying a strain with the Beijing genotype and having drug or multi-drug resistant disease. Our data show that presently transmission of M. tuberculosis strains of the Beijing genotype is not frequent in Latin America. In addition, the lack of association of drug resistant TB and infection with M. tuberculosis of the Beijing genotype observed presently demands efforts to define better the contribution of the virulence and lack of response to treatment to the growing spread of Beijing strains observed in other parts of the world.

  10. Modelling tree ring cellulose δ18O variations in two temperature-sensitive tree species from North and South America

    Directory of Open Access Journals (Sweden)

    A. Lavergne

    2017-11-01

    Full Text Available Oxygen isotopes in tree rings (δ18OTR are widely used to reconstruct past climates. However, the complexity of climatic and biological processes controlling isotopic fractionation is not yet fully understood. Here, we use the MAIDENiso model to decipher the variability in δ18OTR of two temperature-sensitive species of relevant palaeoclimatological interest (Picea mariana and Nothofagus pumilio and growing at cold high latitudes in North and South America. In this first modelling study on δ18OTR values in both northeastern Canada (53.86° N and western Argentina (41.10° S, we specifically aim at (1 evaluating the predictive skill of MAIDENiso to simulate δ18OTR values, (2 identifying the physical processes controlling δ18OTR by mechanistic modelling and (3 defining the origin of the temperature signal recorded in the two species. Although the linear regression models used here to predict daily δ18O of precipitation (δ18OP may need to be improved in the future, the resulting daily δ18OP values adequately reproduce observed (from weather stations and simulated (by global circulation model δ18OP series. The δ18OTR values of the two species are correctly simulated using the δ18OP estimation as MAIDENiso input, although some offset in mean δ18OTR levels is observed for the South American site. For both species, the variability in δ18OTR series is primarily linked to the effect of temperature on isotopic enrichment of the leaf water. We show that MAIDENiso is a powerful tool for investigating isotopic fractionation processes but that the lack of a denser isotope-enabled monitoring network recording oxygen fractionation in the soil–vegetation–atmosphere compartments limits our capacity to decipher the processes at play. This study proves that the eco-physiological modelling of δ18OTR values is necessary to interpret the recorded climate signal more reliably.

  11. Geographically Sourcing Cocaine’s Origin - Delineation of the Nineteen Major Coca Growing Regions in South America

    Science.gov (United States)

    Mallette, Jennifer R.; Casale, John F.; Jordan, James; Morello, David R.; Beyer, Paul M.

    2016-03-01

    Previously, geo-sourcing to five major coca growing regions within South America was accomplished. However, the expansion of coca cultivation throughout South America made sub-regional origin determinations increasingly difficult. The former methodology was recently enhanced with additional stable isotope analyses (2H and 18O) to fully characterize cocaine due to the varying environmental conditions in which the coca was grown. An improved data analysis method was implemented with the combination of machine learning and multivariate statistical analysis methods to provide further partitioning between growing regions. Here, we show how the combination of trace cocaine alkaloids, stable isotopes, and multivariate statistical analyses can be used to classify illicit cocaine as originating from one of 19 growing regions within South America. The data obtained through this approach can be used to describe current coca cultivation and production trends, highlight trafficking routes, as well as identify new coca growing regions.

  12. Origin of samples of Cannabis sativa through insect fragments associated with compacted hemp drug in South America

    Directory of Open Access Journals (Sweden)

    Marcos Patrício Macedo

    2013-06-01

    Full Text Available Origin of samples of Cannabis sativa through insect fragments associated with compacted hemp drug in South America. Insects associated with a seizure of Cannabis sativa L. may indicate the origin of the illicit drug. Nevertheless, no work regarding this subject has been previously published for South America. In the present investigation, seven kilograms of vegetal material (C. sativa were inspected for insect fragments. Three species were identified and used to test the origin of the seizure of cannabis plant material: Euschistus heros (Fabricius, 1794, Thyanta perditor (Fabricius, 1794 (Heteroptera, Pentatomidae, and Cephalotes pusillus (Klug, 1824 (Hymenoptera, Formicidae. These insect species restricted the geographic origin of the drug to the Neotropical region, and their distribution patterns showed an overlap of the State of Mato Grosso (Brazil, Argentina, and Paraguay. Based on this information, two of the three major C. sativa growing areas in South America were excluded: (1 the Colombian territory and (2 northeastern Brazil.

  13. Ancient mitochondrial DNA reveals convergent evolution of giant short-faced bears (Tremarctinae) in North and South America

    OpenAIRE

    Mitchell, Kieren J.; Bray, Sarah C.; Bover, Pere; Soibelzon, Leopoldo; Schubert, Blaine W.; Prevosti, Francisco; Prieto, Alfredo; Martin, Fabiana; Austin, Jeremy J.; Cooper, Alan

    2016-01-01

    The Tremarctinae are a subfamily of bears endemic to the New World, including two of the largest terrestrial mammalian carnivores that have ever lived: the giant, short-faced bears Arctodus simus from North America and Arctotherium angustidens from South America (greater than or equal to 1000 kg). Arctotherium angustidens became extinct during the Early Pleistocene, whereas Arctodus simus went extinct at the very end of the Pleistocene. The only living tremarctine is the spectacled bear (Trem...

  14. Recent population size, trends, and limiting factors for the double-crested Cormorant in Western North America

    Science.gov (United States)

    Adkins, Jessica Y.; Roby, Daniel D.; Lyons, Donald E.; Courtot, Karen N.; Collis, Ken; Carter, Harry R.; Shuford, W. David; Capitolo, Phillip J.

    2014-01-01

    The status of the double-crested cormorant (Phalacrocorax auritus) in western North America was last evaluated during 1987–2003. In the interim, concern has grown over the potential impact of predation by double-crested cormorants on juvenile salmonids (Oncorhynchusspp.), particularly in the Columbia Basin and along the Pacific coast where some salmonids are listed for protection under the United States Endangered Species Act. Recent re-evaluations of double-crested cormorant management at the local, flyway, and federal level warrant further examination of the current population size and trends in western North America. We collected colony size data for the western population (British Columbia, Washington, Oregon, Idaho, California, Nevada, Utah, Arizona, and the portions of Montana, Wyoming, Colorado and New Mexico west of the Continental Divide) by conducting aircraft-, boat-, or ground-based surveys and by cooperating with government agencies, universities, and non-profit organizations. In 2009, we estimated approximately 31,200 breeding pairs in the western population. We estimated that cormorant numbers in the Pacific Region (British Columbia, Washington, Oregon, and California) increased 72% from 1987–1992 to circa 2009. Based on the best available data for this period, the average annual growth rate (λ) of the number of breeding birds in the Pacific Region was 1.03, versus 1.07 for the population east of the Continental Divide during recent decades. Most of the increase in the Pacific Region can be attributed to an increase in the size of the nesting colony on East Sand Island in the Columbia River estuary, which accounts for about 39% of all breeding pairs in the western population and is the largest known breeding colony for the species (12,087 breeding pairs estimated in 2009). In contrast, numbers of breeding pairs estimated in coastal British Columbia and Washington have declined by approximately 66% during this same period. Disturbance at breeding

  15. One-year mortality of HIV-positive patients treated for rifampicin- and isoniazid-susceptible tuberculosis in Eastern Europe, Western Europe, and Latin America.

    Science.gov (United States)

    2017-01-28

    The high mortality among HIV/tuberculosis (TB) coinfected patients in Eastern Europe is partly explained by the high prevalence of drug-resistant TB. It remains unclear whether outcomes of HIV/TB patients with rifampicin/isoniazid-susceptible TB in Eastern Europe differ from those in Western Europe or Latin America. One-year mortality of HIV-positive patients with rifampicin/isoniazid-susceptible TB in Eastern Europe, Western Europe, and Latin America was analysed and compared in a prospective observational cohort study. Factors associated with death were analysed using Cox regression modelsRESULTS:: Three hundred and forty-one patients were included (Eastern Europe 127, Western Europe 165, Latin America 49). Proportions of patients with disseminated TB (50, 58, 59%) and initiating rifampicin + isoniazid + pyrazinamide-based treatment (93, 94, 94%) were similar in Eastern Europe, Western Europe, and Latin America respectively, whereas receipt of antiretroviral therapy at baseline and after 12 months was lower in Eastern Europe (17, 39, 39%, and 69, 94, 89%). The 1-year probability of death was 16% (95% confidence interval 11-24%) in Eastern Europe, vs. 4% (2-9%) in Western Europe and 9% (3-21%) in Latin America; P Eastern Europe were at nearly 3-fold increased risk of death compared with those in Western Europe/Latin America (aHR 2.79 (1.15-6.76); P = 0.023). Despite comparable use of recommended anti-TB treatment, mortality of patients with rifampicin/isoniazid-susceptible TB remained higher in Eastern Europe when compared with Western Europe/Latin America. The high mortality in Eastern Europe was only partially explained by IDU, use of ART and CD4 cell count. These results call for improvement of care for TB/HIV patients in Eastern Europe.

  16. Water and Forest Health: Drought Stress as a Core Driver of Forest Disturbances and Tree Mortality in Western North America

    Science.gov (United States)

    Allen, C. D.; Williams, P.

    2012-12-01

    Increasing warmth and dry climate conditions have affected large portions of western North America in recent years, causing elevated levels of both chronic and acute forest drought stress. In turn, increases in drought stress amplify the incidence and severity of the most significant forest disturbances in this region, including wildfire, drought-induced tree mortality, and outbreaks of damaging insects and diseases. Regional patterns of drought stress and various forest disturbances are reviewed, including interactions among climate and the various disturbance processes; similar global-scale patterns and trends of drought-amplified forest die-off and high-severity wildfire also are addressed. New research is presented that derives a tree-ring-based Forest Drought Stress Index (FDSI) for the three most widespread conifer species (Pinus edulis, Pinus ponderosa, and Pseudotsuga menziesii) in the southwestern US (Arizona, New Mexico), demonstrating nonlinear escalation of FDSI to levels unprecedented in the past 1000 years, in response to both drought and especially recent warming. This new work further highlights strong correlations between drought stress and amplified forest disturbances (fire, bark beetle outbreaks), and projects that by ca. 2050 anticipated regional warming will cause mean FDSI levels to reach extreme levels that may exceed thresholds for the survival of current tree species in large portions of their current range. Given recent trends of forest disturbance and projections for substantially warmer temperatures and greater drought stress for much of western North America in coming years, the growing risks to western forest health are becoming clear. This emerging understanding suggests an urgent need to determine potentials and methods for managing water on-site to maintain the vigor and resilience of western forests in the face of increasing levels of climate-induced water stress.

  17. Simulation of the summer circulation over South America by two regional climate models. Part I: Mean climatology

    Science.gov (United States)

    Fernandez, J. P. R.; Franchito, S. H.; Rao, V. B.

    2006-09-01

    This study investigates the capabilities of two regional models (the ICTP RegCM3 and the climate version of the CPTEC Eta model - EtaClim) in simulating the mean climatological features of the summer quasi-stationary circulations over South America. Comparing the results with the NCEP/DOE reanalysis II data it is seen that the RegCM3 simulates a weaker and southward shifted Bolivian high (BH). But, the Nordeste low (NL) is located close to its climatological position. In the EtaClim the position of the BH is reproduced well, but the NL is shifted towards the interior of the continent. To the east of Andes, the RegCM3 simulates a weaker low level jet and a weaker basic flow from the tropical Atlantic to Amazonia while they are stronger in the EtaClim. In general, the RegCM3 and EtaClim show, respectively a negative and positive bias in the surface temperature in almost all regions of South America. For both models, the correlation coefficients between the simulated precipitation and the GPCP data are high over most of South America. Although the RegCM3 and EtaClim overestimate the precipitation in the Andes region they show a negative bias in general over the entire South America. The simulations of upper and lower level circulations and precipitation fields in EtaClim were better than that of the RegCM3. In central Amazonia both models were unable to simulate the precipitation correctly. The results showed that although the RegCM3 and EtaClim are capable of simulating the main climatological features of the summer climate over South America, there are areas which need improvement. This indicates that the models must be more adequately tuned in order to give reliable predictions in the different regions of South America.

  18. Potential role of vegetation dynamics on recent extreme droughts over tropical South America

    Science.gov (United States)

    Wang, G.; Erfanian, A.; Fomenko, L.

    2017-12-01

    Tropical South America is a drought hot spot. In slightly over a decade (2005-2016), the region encountered three extreme droughts (2005, 2010, and 2016). Recurrent extreme droughts not only impact the region's eco-hydrology and socio-economy, but are also globally important as they can transform the planet's largest rainforest, the Amazon, from a carbon sink to a carbon source. Understanding drought drivers and mechanisms underlying extreme droughts in tropical South America can help better project the fate of the Amazon rainforest in a changing climate. In this study we use a regional climate model (RegCM4.3.4) coupled with a comprehensive land-surface model (CLM4.5) to study the present-day hydroclimate of the region, focusing specifically on what might have caused the frequent recurrence of extreme droughts. In the context of observation natural variability of the global oceanic forcing, we tackle the role of land-atmosphere interactions and ran the model with and without dynamic vegetation to study how vegetation dynamics and carbon-nitrogen cycles may have influenced the drought characteristics. Our results demonstrate skillful simulation of the South American climate in the model, and indicate substantial sensitivity of the region's hydroclimatology to vegetation dynamics. This presentation will compare the role of global oceanic forcing versus regional land surface feedback in the recent recurrent droughts, and will characterize the effects of vegetation dynamics in enhancing the drought severity. Preliminary results on future projections of the regional ecosystem and droughts perspective will be also presented.

  19. Head and neck cancer burden and preventive measures in Central and South America.

    Science.gov (United States)

    Perdomo, Sandra; Martin Roa, Guillermo; Brennan, Paul; Forman, David; Sierra, Mónica S

    2016-09-01

    Central and South America comprise one of the areas characterized by high incidence rates for head and neck cancer. We describe the geographical and temporal trends in incidence and mortality of head and neck cancers in the Central and South American region in order to identify opportunities for intervention on the major identified risk factors: tobacco control, alcohol use and viral infections. We obtained regional- and national-level incidence data from 48 population-based cancer registries in 13 countries and cancer deaths from the WHO mortality database for 18 countries. Age-standardized incidence (ASR) and mortality (ASMR) rates per 100,000 person-years were estimated. Brazil had the highest incidence rates for oral and pharyngeal cancer in the region for both sexes, followed by Cuba, Uruguay and Argentina. Cuba had the highest incidence and mortality rates of laryngeal cancer in the region for males and females. Overall, males had rates about four times higher than those in females. Most countries in the region have implemented WHO recommendations for both tobacco and alcohol public policy control. Head and neck squamous-cell cancer (HNSCC) incidence and mortality rates in the Central and South America region vary considerably across countries, with Brazil, Cuba, French Guyana, Uruguay and Argentina experiencing the highest rates in the region. Males carry most of the HNSCC burden. Improvement and implementation of comprehensive tobacco and alcohol control policies as well as the monitoring of these factors are fundamental to prevention of head and neck cancers in the region. Copyright © 2015 International Agency for Research on Cancer. Published by Elsevier Ltd.. All rights reserved.

  20. Polychaeta Orbiniidae from Antarctica, the Southern Ocean, the Abyssal Pacific Ocean, and off South America.

    Science.gov (United States)

    Blake, James A

    2017-01-12

    The orbiniid polychaetes chiefly from Antarctic and subantarctic seas and off South America are described based on collections of the National Museum of Natural History and new material from surveys conducted by the United States Antarctic Program and other federal and privately funded sources as well as participation in international programs. A total of 44 species of Orbiniidae distributed in 10 genera are reported from the Pacific Ocean and waters off South America and Antarctica. Twenty-one species are new to science; one species is renamed. Berkeleyia heroae n. sp., B. abyssala n. sp., B. weddellia n. sp.; B. hadala n. sp., Leitoscoloplos simplex n. sp., L. plataensis n. sp., L. nasus n. sp., L. eltaninae n. sp., L. phyllobranchus n. sp., L. rankini n. sp., Scoloplos bathytatus n. sp., S. suroestense n. sp., Leodamas hyphalos n. sp., L. maciolekae n. sp., L. perissobranchiatus n. sp., Califia bilamellata n. sp., Orbinia orensanzi n. sp., Naineris antarctica n. sp., N. argentiniensis n. sp., Orbiniella spinosa n. sp., and O. landrumae n. sp. are new to science. A new name, Naineris furcillata, replaces N. chilensis Carrasco, 1977, a junior homonym of N. dendtritica chilensis Hartmann‑Schröder, 1965, which is raised to full species status. Leodamas cochleatus (Ehlers, 1900) is removed from synonymy and redescribed. A neotype is established for Leodamas verax Kinberg, 1966, the type species. A general overview of Leodamas species is provided. The Leitoscoloplos kerguelensis (McIntosh, 1885) complex is reviewed and partially revised. Definitions of the genera of the Orbiniidae are updated to conform to recently described taxa. Several new synonymies are proposed following a reexamination of previously described type specimens. The morphological characters used to identify and classify orbiniids are reviewed. The biogeographic and bathymetric distributions of the South American and Southern Ocean orbiniid fauna are reviewed.

  1. Distributional changes in the western Burrowing Owl (Athene cunicularia hypugaea) in North America from 1967 to 2008

    Science.gov (United States)

    Macias-Duarte, Alberto; Conway, Courtney J.

    2015-01-01

    The quantification of shifts in bird distributions in response to climate change provides an opportunity to gain a deeper understanding of the processes that influence species persistence. We used data from the North American Breeding Bird Survey (BBS) to document changes in the distributional limits of the western Burrowing Owl (Athene cunicularia hypugaea) from 1967 to 2008. We used logistic regression to model presence probability (p) as a function of longitude, latitude, and year. We modeled a linear trend in logit(p) through time with slope and intercept modeled as a double Fourier series of longitude and latitude. We found that the western Burrowing Owl has experienced an intriguing southward shift in the northern half of its breeding range, contrary to what is predicted by most species niche models and what has been observed for many other species in North America. The breeding range of the Burrowing Owl has been shrinking near its northern, western, and eastern edges. Our model detected the population declines that were observed in California and eastern Washington, in locations where maps based on route-specific estimating equations had predicted significant population increases. We suggest that the northern boundary of the breeding distribution of the western Burrowing Owl has contracted southward and the southern boundary of the species' breeding distribution has expanded southward into areas of northern Mexico that were formerly used only by wintering migrants.

  2. ACADEMIC DEPENDENCY ON WESTERN DISCIPLINARY KNOWLEDGE AND CAPTIVE MIND AMONG SOUTH ASIAN SOCIOLOGISTS: A CRITIQUE

    Directory of Open Access Journals (Sweden)

    Siri Gamage

    2016-10-01

    Full Text Available This paper examines how academic dependency of South Asia on the West has resulted in what has been termed ‘captive mind’, and its impact on the knowledge production process of South Asia. To this end, it observes that the relationship between Western centres of Social Science teaching and learning vs. those of the global South, in particular Asia, is an unequal one that stems from the colonial past, leading to the treatment of Western methods and types of knowledge production as superior and therefore worthy of imitation. The application of American and European methods of studying the Social Sciences to Asian settings without due adaptation, it argues, has rendered South Asian Sociology largely incapable of generating original knowledge to contribute to the growth of an emancipatory sociological imagination that will function for the benefit of the populace. Therefore it appeals to South Asian Sociologists – and other Social Scientists – to abandon the practice of studying regional social institutions as if these are exotic phenomena, practices, norms and ritual, and evolve their disciplinary framework in more critical, creative, and relevant ways.

  3. Some preliminary results of a worldwide seismicity estimation: a case study of seismic hazard evaluation in South America

    Directory of Open Access Journals (Sweden)

    C. V. Christova

    2000-06-01

    Full Text Available Global data have been widely used for seismicity and seismic hazard assessment by seismologists. In the present study we evaluate worldwide seismicity in terms of maps of maximum observed magnitude (Mmax, seismic moment (M 0 and seismic moment rate (M 0S. The data set used consists of a complete and homogeneous global catalogue of shallow (h £ 60 km earthquakes of magnitude MS ³ 5.5 for the time period 1894-1992. In order to construct maps of seismicity and seismic hazard the parameters a and b derived from the magnitude-frequency relationship were estimated by both: a the least squares, and b the maximum likelihood, methods. The values of a and b were determined considering circles centered at each grid point 1° (of a mesh 1° ´1° and of varying radius, which starts from 30 km and moves with a step of 10 km. Only a and b values which fulfill some predefined conditions were considered in the further procedure for evaluating the seismic hazard maps. The obtained worldwide M max distribution in general delineates the contours of the plate boundaries. The highest values of M max observed are along the circum-Pacific belt and in the Himalayan area. The subduction plate boundaries are characterized by the largest amount of M 0 , while areas of continental collision are next. The highest values of seismic moment rate (per 1 year and per equal area of 10 000 km 2 are found in the Southern Himalayas. The western coasts of U.S.A., Northwestern Canada and Alaska, the Indian Ocean and the eastern rift of Africa are characterized by high values of M 0 , while most of the Pacific subduction zones have lower values of seismic moment rate. Finally we analyzed the seismic hazard in South America comparing the predicted by the NUVEL1 model convergence slip rate between Nazca and South America plates with the average slip rate due to earthquakes. This consideration allows for distinguishing between zones of high and low coupling along the studied convergence

  4. Annual ryegrass toxicity in Thoroughbred horses in Ceres in the Western Cape Province, South Africa

    Directory of Open Access Journals (Sweden)

    J.D. Grewar

    2009-05-01

    Full Text Available An outbreak of annual ryegrass toxicity occurred on a Thoroughbred stud in Ceres in the Western Cape Province of South Africa. This is the 1st report of annual ryegrass toxicity in horses in South Africa, although the condition has been reported in cattle and sheep populations in the past. Annual ryegrass toxicity is characterised by a variety of neurological signs including tremors, convulsions, recumbency and in many cases death. The description of the outbreak includes the history, clinical presentation and treatment protocol administered during the outbreak. Various epidemiological variables and their influence in the outbreak are also considered.

  5. Stable carbon isotopic assessment of prehistoric diets in the south-western Cape, Cape Town, South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Sealy, J C

    1984-01-01

    This thesis consists of a stable carbon isotopic assessment of the diets of the Holocene human inhabitants of the south-western Cape, South-Africa. Samples of the foods these people ate were collected from each of the four major physiographic zones in the area, and their /sup 13/C//sup 12/C ratios measured. A total of more than 200 such analyses enabled the estimation of the average delta /sup 13/C values of prehistoric human diets in each zone. This information is used to interpret delta /sup 13/C measurements on a series of archaeological human skeletons. The results are consistent with a model of prehistoric subsistence behaviour in which people living at the coast made intensive use of marine food resources throughout the Holocene, consuming such a large proportion of these foods that they must have spent much, if not all of their time at the coast. Inland skeletons reflect an almost entirely terrestrial diet. These results contradict hypotheses about seasonal population movements between the coast and the interior generated from excavated archaeological material. Considerable changes in many of our current views of the Late Stone Age of the south-western Cape will have to be made in order to accommodate these data.

  6. Meteorological and oceanographic aspects of a winter storm over the south-western Cape Province, South Africa

    International Nuclear Information System (INIS)

    Jury, M.R.; Shillington, F.A.; Prestidge, G.; Maxwell, C.D.

    1986-01-01

    In May the southern hemisphere circumpolar jet stream accelerates in response to a growing temperature gradient between the pole and equator. Initially, the jet stream may 'spin up' in pulses, causing the upper air current to become unstable and to meander equatorwards out of the higher latitudes (40-50 degrees S). Winter storms induced by the jet stream and which move, from west to east, to the south of the African continent are then guided by the upper air currents further north. Between 15 and 17 May 1984, such a sequence of synoptic weather events developed and the south-western Cape came under the influence of the 'roaring 40's'. In this article a chronology of the storm and its meteorological effects are described using data collected at the Koeberg nuclear power station, the Cape Town Airport Weather Office and across the south-western Cape. The destructive effects of the storm, particularly felt along the coast as a result of large swells and a significant storm surge, are discussed

  7. First case of New Delhi metallo-β-lactamase in Klebsiella pneumoniae from Ecuador: An update for South America

    Directory of Open Access Journals (Sweden)

    Daniel Romero-Alvarez

    2017-12-01

    Full Text Available Objectives: To describe a clinical case of Klebsiella pneumoniae harboring a New Delhi metallo-β-lactamase (NDM plasmid in Ecuador and to present a map of reports of NDM isolates in South America. Methods: The modified Hodge test, carbapenem inactivation method, imipenem–EDTA disk method (synergy, and Rapidec Carba NP test were used to identify antibiotic resistance mechanisms. The presence of resistance genes was explored with a conjugation assay, and molecular confirmation of NDM was performed by PCR and DNA sequencing. Plasmid characterization was conducted by PCR-based replicon typing. A literature review was performed in Google Scholar and PubMed to identify reports from South America. Results: An HIV-infected patient, who had never traveled abroad, developed a bloodstream infection caused by K. pneumoniae ST147 harboring the NDM-1 resistance gene in a plasmid from the IncA/C group. Local circulation of NDM has also been described in other South American countries, in particular in Colombia and Brazil, although published scientific records were not found for other countries. Conclusions: This report presents the first evidence of autochthonous circulation of the NDM-1 resistance gene harbored by an IncA/C plasmid isolated from a K. pneumoniae ST147 in Ecuador. Efforts should be implemented to monitor and characterize the spatial and temporal distribution of NDM in Ecuador and other countries of South America. Keywords: NDM, South America, Klebsiella pneumoniae, Antibiotic resistance, Plasmid

  8. Philorhizus occitanus sp. n. from the South-Western Alps (Piedmont, Italy (Coleoptera: Carabidae, Dromiini

    Directory of Open Access Journals (Sweden)

    Gianni Allegro

    2015-12-01

    Full Text Available Philorhizus occitanus sp. n. from the South-Western Alps (Ellero Valley and Maira Valley is described. This new species is similar to P. crucifer and P. notatus as far as the external morphology is concerned, but it is distinguished by the color pattern and the shape of elytra, as well as by the features of the median lobe of aedeagus. P. liguricus, which is easily distinguished from P. occitanus sp. n. by the external morphology, was already recorded from the South-Western Alps and from the Ligurian Apennines. P. occitanus sp. n. is a likely close relative of P. notatus, although the affinities of this relict flightless new species remain uncertain.

  9. Prevalence of Legionella spp. in water systems of hospitals and hotels in South Western Greece.

    Science.gov (United States)

    Fragou, K; Kokkinos, P; Gogos, C; Alamanos, Y; Vantarakis, A

    2012-01-01

    The aim of the present study was to determine the prevalence of Legionella spp. in water systems of hospitals and hotels located in South Western Greece, to study the molecular epidemiology of the isolated strains and their possible association with bacterial contamination (total count and Pseudomonas aeruginosa), the water pH, and temperature. A prevalence survey for Legionella spp. by culturing techniques in water distribution systems of eight hospitals and nine hotels occurred in South Western Greece. Water sampling and microbiological analysis were carried out following the ISO methods. Legionella pneumophila was detected in 33% and 36% of the distribution systems of hospitals and hotels, respectively. Our survey results suggest a frequent prevalence of elevated concentrations of Legionella spp. in water systems of hospitals and hotels. Our investigation has confirmed the need to regularly monitor the microbiological condition of water systems in hospitals and hotels.

  10. The carbon balance of South America: a review of the status, decadal trends and main determinants

    Directory of Open Access Journals (Sweden)

    M. Gloor

    2012-12-01

    Full Text Available We summarise the contemporary carbon budget of South America and relate it to its dominant controls: population and economic growth, changes in land use practices and a changing atmospheric environment and climate. Component flux estimate methods we consider sufficiently reliable for this purpose encompass fossil fuel emission inventories, biometric analysis of old-growth rainforests, estimation of carbon release associated with deforestation based on remote sensing and inventories, and agricultural export data. Alternative methods for the estimation of the continental-scale net land to atmosphere CO2 flux, such as atmospheric transport inverse modelling and terrestrial biosphere model predictions, are, we find, hampered by the data paucity, and improved parameterisation and validation exercises are required before reliable estimates can be obtained. From our analysis of available data, we suggest that South America was a net source to the atmosphere during the 1980s (~ 0.3–0.4 Pg C a−1 and close to neutral (~ 0.1 Pg C a−1 in the 1990s. During the latter period, carbon uptake in old-growth forests nearly compensated for the carbon release associated with fossil fuel burning and deforestation.

    Annual mean precipitation over tropical South America as inferred from Amazon River discharge shows a long-term upward trend. Although, over the last decade dry seasons have tended to be drier, with the years 2005 and 2010 in particular experiencing strong droughts. On the other hand, precipitation during the wet seasons also shows an increasing trend. Air temperatures have also increased slightly. Also with increases in atmospheric CO2 concentrations, it is currently unclear what effect these climate changes are having on the forest carbon balance of the region. Current indications are that the forests of the Amazon Basin have acted as a substantial long-term carbon sink, but with the most recent

  11. Aspects of governmental job-creation efforts in Western Europe and North America.

    OpenAIRE

    Hollister RG

    1986-01-01

    ILO pub-WEP pub. Working paper, comparison of employment policies for employment creation in Western Europe and the USA - covers job creation measures, target groups, financing, and the relationships between job creation and economic policy and social policies (esp. Social security); looks at problems of design implementation and evaluation of employment creation projects; discusses obstacles to employment creation in the context of economic recession in Western Europe, and in a developing co...

  12. Changes in the forest ecosystems in areas impacted by aridization in south-western Romania

    OpenAIRE

    Pravalie, Remus; Sîrodoev, Igor; Peptenatu, Daniel

    2014-01-01

    Background In the past few decades, global climate change has accentuated the intensification of aridization in South-Western Romania, with direct and indirect consequences on the quality of forest ecosystems. In addition to qualitative deterioration, the quantitative changes brought about by intensive anthropic deforestation have created the conditions for a decline in the size of forest areas on vast tracts of land. The paper aims to analyze the qualitative and quantitative changes in the f...

  13. First report of Pineus strobi (Hartig, 1839) (Hemiptera: Adelgidae) in western North America

    Science.gov (United States)

    Molly Darr; Scott Salom; Rachel K. Brooks; Robert G. Foottit; Gary L. Miller; Nathan P. Havill

    2018-01-01

    The pine bark adelgid, Pineus strobi (Hartig, 1839) (Hempitera: Adelgidae), is native to eastern North America and is found throughout the natural range of its main host species, eastern white pine, Pinus strobus L. (Pinaceae), which stretches from the Atlantic coast, west to Ontario and Minnesota (Drooz 1985). For the first...

  14. First report of Pineus strobi (Hartig) (Hemiptera: Adelgidae) in western North America

    Science.gov (United States)

    The pine bark adelgid, Pineus strobi (Hartig, 1839) (Hempitera: Adelgidae), is native to eastern North America. Its main host species is eastern white pine, Pinus strobus L. Pineus strobi is reported here for the first time from Washington, Colorado, Saskatchewan and tentatively Oregon by identifica...

  15. A simple tool for estimating throughfall nitrogen deposition in forests of western North America using lichens

    Science.gov (United States)

    Heather T. Root; Linda H. Geiser; Mark E. Fenn; Sarah Jovan; Martin A. Hutten; Suraj Ahuja; Karen Dillman; David Schirokauer; Shanti Berryman; Jill A. McMurray

    2013-01-01

    Anthropogenic nitrogen (N) deposition has had substantial impacts on forests of North America. Managers seek to monitor deposition to identify areas of concern and establish critical loads, which define the amount of deposition that can be tolerated by ecosystems without causing substantial harm. We present a new monitoring approach that estimates throughfall inorganic...

  16. The Luzula comosa complex (Luzula section Luzula, Juncaceae) in western North America

    Czech Academy of Sciences Publication Activity Database

    Zika, P. F.; Wilson, B. A.; Kirschner, Jan

    2015-01-01

    Roč. 192, č. 4 (2015), s. 201-229 ISSN 1179-3155 Institutional research plan: CEZ:AV0Z60050516 Institutional support: RVO:67985939 Keywords : Luzula * Pacific North America * taxonomy Subject RIV: EF - Botanics Impact factor: 1.087, year: 2015

  17. A new GPS velocity field in the south-western Balkans: insights for continental dynamics

    Science.gov (United States)

    D'Agostino, N.; Avallone, A.; Duni, L.; Ganas, A.; Georgiev, I.; Jouanne, F.; Koci, R.; Kuka, N.; Metois, M.

    2017-12-01

    The Balkans peninsula is an area of active distributed deformation located at the southern boundary of the Eurasian plate. Relatively low strain rates and logistical reasons have so far limited the characterization and definition of the active tectonics and crustal kinematics. The increasing number of GNSS stations belonging to national networks deployed for scientific and cadastral purposes, now provides the opportunity to improve the knowledge of the crustal kinematics in this area and to define a cross-national velocity field that illuminates the active tectonic deformation. In this work we homogeneously processed the data from the south western Balkans and neighbouring regions using available rinex files from scientific and cadastral networks (ALBPOS, EUREF, HemusNET, ITALPOS, KOPOS, MAKPOS, METRICA, NETGEO, RING, TGREF). In order to analyze and interpret station velocities relative to the Eurasia plate and to reduce the common mode signal, we updated the Eurasian terrestrial reference frame described in Métois et al. 2015. Starting from this dataset we present a new GPS velocity field covering the south western part of the Balkan Peninsula. Using this new velocity field, we derive the strain rate tensor to analyze the regional style of the deformation. Our results (1) improve the picture of the general southward flow of the crust characterizing the south western Balkans behind the contractional belt at the boundary with Adriatic and (2) provide new key elements for the understanding of continental dynamics in this part of the Eurasian plate boundary.

  18. Land Cover Characterization and Mapping of South America for the Year 2010 Using Landsat 30 m Satellite Data

    Directory of Open Access Journals (Sweden)

    Chandra Giri

    2014-10-01

    Full Text Available Detailed and accurate land cover and land cover change information is needed for South America because the continent is in constant flux, experiencing some of the highest rates of land cover change and forest loss in the world. The land cover data available for the entire continent are too coarse (250 m to 1 km for resource managers, government and non-government organizations, and Earth scientists to develop conservation strategies, formulate resource management options, and monitor land cover dynamics. We used Landsat 30 m satellite data of 2010 and prepared the land cover database of South America using state-of-the-science remote sensing techniques. We produced regionally consistent and locally relevant land cover information by processing a large volume of data covering the entire continent. Our analysis revealed that in 2010, 50% of South America was covered by forests, 2.5% was covered by water, and 0.02% was covered by snow and ice. The percent forest area of South America varies from 9.5% in Uruguay to 96.5% in French Guiana. We used very high resolution (<5 m satellite data to validate the land cover product. The overall accuracy of the 2010 South American 30-m land cover map is 89% with a Kappa coefficient of 79%. Accuracy of barren areas needs to improve possibly using multi-temporal Landsat data. An update of land cover and change database of South America with additional land cover classes is needed. The results from this study are useful for developing resource management strategies, formulating biodiversity conservation strategies, and regular land cover monitoring and forecasting.

  19. Relative influence of human harvest, carnivores, and weather on adult female elk survival across western North America

    Science.gov (United States)

    Brodie, Jedediah; Johnson, Heather; Mitchell, Michael; Zager, Peter; Proffitt, Kelly; Hebblewhite, Mark; Kauffman, Matthew; Johnson, Bruce; Bissonette, John; Bishop, Chad; Gude, Justin; Herbert, Jeff; Hersey, Kent R.; Hurley, Mark; Lukacs, Paul M.; McCorquodale, Scott; McIntire, Eliot; Nowak, Josh; Sawyer, Hall; Smith, Douglas; White, P.J.

    2013-01-01

    Well-informed management of harvested species requires understanding how changing ecological conditions affect demography and population dynamics, information that is lacking for many species. We have limited understanding of the relative influence of carnivores, harvest, weather and forage availability on elk Cervus elaphus demography, despite the ecological and economic importance of this species. We assessed adult female survival, a key vital rate for population dynamics, from 2746 radio-collared elk in 45 populations across western North America that experience wide variation in carnivore assemblage, harvest, weather and habitat conditions. Proportional hazard analysis revealed that 'baseline' (i.e. not related to human factors) mortality was higher with very high winter precipitation, particularly in populations sympatric with wolves Canis lupus. Mortality may increase via nutritional stress and heightened vulnerability to predation in snowy winters. Baseline mortality was unrelated to puma Puma concolor presence, forest cover or summer forage productivity. Cause-specific mortality analyses showed that wolves and all carnivore species combined had additive effects on baseline elk mortality, but only reduced survival by baseline adult female elk mortality from wolves in years with high winter precipitation could affect elk abundance as winters across the western US become drier and wolves recolonize portions of the region. In the absence of human harvest, wolves had additive, although limited, effects on mortality. However, human harvest, and its apparent use by managers to offset predation, primarily controls overall variation in adult female mortality. Altering harvest quotas is thus a strong tool for offsetting impacts of carnivore recolonization and shifting weather patterns on elk across western North America.

  20. Twenty-five years of violence: the epidemiology of terrorism in South America.

    Science.gov (United States)

    Báez, Amado Alejandro; Sztajnkrycer, Matthew D; Zane, Richard; Giräldez, Ediza

    2008-01-01

    Terrorism is a global public health burden. South Americans have been victims of terrorism for many decades. While the causes vary, the results are the same: death, disability, and suffering. The objective of this study was to perform a comprehensive, epidemiological, descriptive study of terrorist incidents in South America. This is a cross-sectional, descriptive study. Data from January 1971 to July 2006 was selected using the RAND Terrorism Chronology 1968-1997 and RAND-Memorial Institute for Prevention of Terrorism (MIPT) Terrorism Incident database (1998-Present). Statistical significance was set at 0.05. The database reported a total of 2,997 incidents in South American countries that resulted in 3,435 victims with injuries (1.15 per incident) and 1,973 fatalities (0.66 per incident). The overall case fatality ratio (CFR) was 35.8%. Colombia had the majority of incidents with 57.9% (1,734 of 2,997), followed by Peru with 363 (12.1%), and Argentina with 267 (8.9%). The highest individual CFR occurred in Paraguay (83.3%), and the lowest in Chile with 4.8%. Of the total injuries and deaths, Colombia had 66.1% (2,269 of 2,997) of all injuries and 75.2% (1,443 out of 1,920) of all deaths. Living in the country of Colombia was associated with a 16 times greater likelihood of becoming a victim of terrorist violence [odds ratio (OR) 16.15; 95% CI 13.45 to 19.40; p < 0.0001]. The predominant method of choice for terrorist incidents was the use of conventional explosives with 2,543 of2,883 incidents (88.2%). Terrorist incidents in South America have accounted for nearly 2,000 deaths, with conventional explosive devices as the predominant method of choice. Understanding the nature of terrorist attacks and the medical consequences assist emergency preparedness and disaster management officials in allocating resources and preparing for potential future events.

  1. Biostratigraphy of the upper Bajocian-middle Callovian (Middle Jurassic), South America

    Science.gov (United States)

    Riccardi, A. C.; Westermann, G. E. G.; Elmi, S.

    The biostratigraphic division of the upper Bajocian-middle Callovian of South America is based on ammonites from different sections of the following provinces and regions: Neuquén, Mendoza, and San Juan in Argentina; Malleco, Linares, Talca, Atacama, Antofagasta, and Tarapacá in Chile. The complete upper Bajocian-middle Callovian succession includes the following biostratigraphic units: the Megasphaeroceras magnum assemblage zone, lowermost upper Bajocian; the Cadomites-Tulitidae mixed assemblages, (?lower) middle and upper Bathonian; the Steinmanni zone, index Lilloettia steinmanni (Spath), uppermost Bathonian, with two local horizons— Stenocephalites gerthi horizon (Argentina) and Choffatia jupiter horizon (northern Chile); the Vergarensis zone, index Eurycephalites vergarensis (Burck.), near the Bathonian-Callovian boundary; the Bodenbenderi zone, index Neuqueniceras (Frickites) bodenbenderi (Tornq.), lower Callovian; the Proximum zone, index Hecticoceras proximum Elmi, uppermost lower Callovian; and the Rehmannia (Loczyceras) patagoniensis horizon, middle Callovian.

  2. Doses from 222Rn, 226Ra, and 228Ra in groundwater from Guarani aquifer, South America.

    Science.gov (United States)

    Bonotto, D M

    2004-01-01

    Groundwater samples were analysed for 222Rn, 226Ra, and 228Ra in Guarani aquifer spreading around 1 million km2 within four countries in South America, and it was found that their activity concentrations are lognormally distributed. Population-weighted average activity concentration for these radionuclides allowed to estimate a value either slightly higher (0.13 mSv/year) than 0.1 mSv for the total effective dose or two times higher (0.21 mSv/year) than this limit, depending on the choice of the dose conversion factor. Such calculation adds useful information for the appropriate management of this transboundary aquifer that is socially and economically very important to about 15 million inhabitants living in Brazil, Argentina, Uruguay and Paraguay.

  3. Doses from 222Rn, 226Ra, and 228Ra in groundwater from Guarani aquifer, South America

    International Nuclear Information System (INIS)

    Bonotto, D.M.

    2004-01-01

    Groundwater samples were analysed for 222 Rn, 226 Ra, and 228 Ra in Guarani aquifer spreading around 1 million km 2 within four countries in South America, and it was found that their activity concentrations are lognormally distributed. Population-weighted average activity concentration for these radionuclides allowed to estimate a value either slightly higher (0.13 mSv/year) than 0.1 mSv for the total effective dose or two times higher (0.21 mSv/year) than this limit, depending on the choice of the dose conversion factor. Such calculation adds useful information for the appropriate management of this transboundary aquifer that is socially and economically very important to about 15 million inhabitants living in Brazil, Argentina, Uruguay and Paraguay

  4. A contribution to the subdivision of the precambrian in South America

    International Nuclear Information System (INIS)

    Brito Neves, B.B. de; Teixeira, W.; Tassinari, C.C.G.; Kawashita, K.

    1990-01-01

    On the shield areas of the South America continent (about 5,000,000 km 2 large) there are about 17,000 geochronological determinations available. More than 75% of this amount has been carried out in the Centro de Pesquisas Geocronologicas da Universidade de Sao Paulo, CPGeo-USP, in the last 25 years. The majority of these data were accomplished through Rb-Sr (ca.60%) and K-Ar (ca.40%) methods. The author tried to work this amount of data on a coherent way according to the progress observed in the geologic and geotectonic knowledge during the last two decades. One of the fundamental goals was to outline an up-to-date subdivision for the Precambrian of this continent, having in mind a contribution to the International Commission on Stratigraphy (ICS), Subcommission of Precambrian Stratigraphy (SPS) of the IUGS. (author)

  5. ITS-2 sequences-based identification of Trichogramma species in South America

    Directory of Open Access Journals (Sweden)

    R. P. Almeida

    Full Text Available Abstract ITS2 (Internal transcribed spacer 2 sequences have been used in systematic studies and proved to be useful in providing a reliable identification of Trichogramma species. DNAr sequences ranged in size from 379 to 632 bp. In eleven T. pretiosum lines Wolbachia-induced parthenogenesis was found for the first time. These thelytokous lines were collected in Peru (9, Colombia (1 and USA (1. A dichotomous key for species identification was built based on the size of the ITS2 PCR product and restriction analysis using three endonucleases (EcoRI, MseI and MaeI. This molecular technique was successfully used to distinguish among seventeen native/introduced Trichogramma species collected in South America.

  6. LATTES: a new gamma-ray detector concept for South America

    Directory of Open Access Journals (Sweden)

    Assis P.

    2017-01-01

    Full Text Available Currently the detection of Very High Energy gamma-rays for astrophysics rely on the measurement of the Extensive Air Showers (EAS either using Cherenkov detectors or EAS arrays with larger field of views but also larger energy thresholds. In this talk we present a novel hybrid detector concept for a EAS array with an improved sensitivity in the lower energies (~ 100 GeV. We discuss its main features, capabilities and present preliminary results on its expected perfomances and sensitivities.This wide field of view experiment is planned to be installed at high altitude in South America making it a complementary project to the planned Cherenkov telescope experiments and a powerful tool to trigger further observations of variable sources and to detect transients phenomena.

  7. [Health, globalization and interculturalism: an anthropological approach to the situation of indigenous peoples in South America].

    Science.gov (United States)

    Hita, Susana Ramírez

    2014-10-01

    This article reflects upon the impact of globalization and interculturalism on the living conditions of indigenous peoples in South America. Through two examples - Bolivia and Argentina - it is seen how health interculturalism has transformed into a discourse and a practice that both global organizations and most Latin American countries have used to assimilate and attract indigenous communities. Traditional medicine is respected and valued without proposing changes to improve the living conditions of these population groups. This is especially true in those areas where land is being expropriated or contaminated with the extraction of gas, oil, minerals and the construction of dams, along with indiscriminate deforestation of the rainforest. Health/illness cannot be separated from the territorial conditions of these peoples since environmental health is critical for their survival.

  8. Acoustic regulations for housing and schools in Europe and South America

    DEFF Research Database (Denmark)

    Machimbarrena, Maria; Rasmussen, Birgit

    2017-01-01

    Acoustic regulations for housing and schools exist in most countries in Europe, the main reasons being protection of health of citizens in their homes and optimizing learning and work conditions in schools. Comparative studies in Europe have shown a high diversity of descriptors and limit values...... for acoustic requirements. Considering globalization and noise as a health issue, it is important to extend attention to other parts of the world and establish dialogue and cooperation. As a pilot study, acoustic regulations in three countries in South America, namely Argentina, Brazil and Chile, have been...... awareness among authorities and building industry and to exchange experience about construction solutions. The paper includes examples of specific acoustic requirements on airborne and impact sound insulation, noise from traffic and from service equipment for housing and schools and in addition...

  9. Satellite-based detection of volcanic sulphur dioxide from recent eruptions in Central and South America

    Directory of Open Access Journals (Sweden)

    D. Loyola

    2008-01-01

    Full Text Available Volcanic eruptions can emit large amounts of rock fragments and fine particles (ash into the atmosphere, as well as several gases, including sulphur dioxide (SO2. These ejecta and emissions are a major natural hazard, not only to the local population, but also to the infrastructure in the vicinity of volcanoes and to aviation. Here, we describe a methodology to retrieve quantitative information about volcanic SO2 plumes from satellite-borne measurements in the UV/Visible spectral range. The combination of a satellite-based SO2 detection scheme and a state-of-the-art 3D trajectory model enables us to confirm the volcanic origin of trace gas signals and to estimate the plume height and the effective emission height. This is demonstrated by case-studies for four selected volcanic eruptions in South and Central America, using the GOME, SCIAMACHY and GOME-2 instruments.

  10. An enigmatic aquatic snake from the Cenomanian of Northern South America

    Directory of Open Access Journals (Sweden)

    Adriana Albino

    2016-05-01

    Full Text Available We report the first record of a snake from the Cretaceous of northern South America. The remains come from the La Luna Formation (La Aguada Member, Cenomanian of Venezuela and consist of several vertebrae, which belong to the precloacal region of the vertebral column. Comparisons to extant and extinct snakes show that the remains represent a new taxon, Lunaophis aquaticus gen. et sp nov. An aquatic mode of life is supported by the ventral position of the ribs, indicating a laterally compressed body. The systematic relationships of this new taxon are difficult to determine due to the scarcity of fossil material; it is, however, a representative of an early lineage of snakes that exploited tropical marine pelagic environments, as reflected by the depositional conditions of the La Aguada Member. Lunaophis is also the first aquatic snake from the Cenomanian found outside of the African and European Tethyan and Boreal Zones.

  11. Checklist of helminths from lizards and amphisbaenians (Reptilia, Squamata of South America

    Directory of Open Access Journals (Sweden)

    RW Ávila

    2010-01-01

    Full Text Available A comprehensive and up to date summary of the literature on the helminth parasites of lizards and amphisbaenians from South America is herein presented. One-hundred eighteen lizard species from twelve countries were reported in the literature harboring a total of 155 helminth species, being none acanthocephalans, 15 cestodes, 20 trematodes and 111 nematodes. Of these, one record was from Chile and French Guiana, three from Colombia, three from Uruguay, eight from Bolivia, nine from Surinam, 13 from Paraguay, 12 from Venezuela, 27 from Ecuador, 17 from Argentina, 39 from Peru and 103 from Brazil. The present list provides host, geographical distribution (with the respective biome, when possible, site of infection and references from the parasites. A systematic parasite-host list is also provided.

  12. Preliminary report on osteochondrosis in cattle in the north-western parts of South Africa

    Directory of Open Access Journals (Sweden)

    Leon Prozesky

    2016-07-01

    Full Text Available The north-western part of South Africa, in particular, is well known for mineral imbalances. Aphosphorosis, resulting in rickets and osteomalacia, received a lot of attention at the turn of the nineteenth century (1882–1912. This was followed in 1997 by research on Vryburg hepatosis, another area-specific mineral imbalance–related disease in young calves reared on manganese-rich soil derived from the weathering of dolomitic (carbonate rock formations. In 1982, a totally new syndrome (osteochondrosis manifested in, amongst others, areas in South Africa where aphosphorosis was rife. Osteochondrosis was also identified in the south-western parts of Namibia as well as southern Botswana and other areas in South Africa. Osteochondrosis has a multifactorial aetiology and this study focused on the role of minerals, particularly phosphorus, in the development of the disease. A significant improvement in the clinical signs in experimental animals and a reduction of osteochondrosis occurred on farms where animals received bioavailable trace minerals and phosphorus as part of a balanced lick. An increase in the occurrence of the disease on farms during severe drought conditions in 2012–2013 prompted researchers to investigate the possible role of chronic metabolic acidosis in the pathogenesis of the disease.

  13. Agricultural impacts of glyphosate-resistant soybean cultivation in South America.

    Science.gov (United States)

    Cerdeira, Antonio L; Gazziero, Dionsio L P; Duke, Stephen O; Matallo, Marcus B

    2011-06-08

    In the 2009/2010 growing season, Brazil was the second largest world soybean producer, followed by Argentina. Glyphosate-resistant soybeans (GRS) are being cultivated in most of the soybean area in South America. Overall, the GRS system is beneficial to the environment when compared to conventional soybean. GRS resulted in a significant shift toward no-tillage practices in Brazil and Argentina, but weed resistance may reduce this trend. Probably the highest agricultural risk in adopting GRS in Brazil and South America is related to weed resistance due to use of glyphosate. Weed species in GRS fields have shifted in Brazil to those that can more successfully withstand glyphosate or to those that avoid the time of its application. Five weed species, in order of importance, Conyza bonariensis (L.) Cronquist, Conyza canadensis (L.) Cronquist, Lolium multiflorum Lam., Digitaria insularis (L.) Mez ex Ekman, and Euphorbia heterophylla L., have evolved resistance to glyphosate in GRS in Brazil. Conyza spp. are the most difficult to control. A glyphosate-resistant biotype of Sorghum halepense L. has evolved in GRS in Argentina and one of D. insularis in Paraguay. The following actions are proposed to minimize weed resistance problem: (a) rotation of GRS with conventional soybeans in order to rotate herbicide modes of action; (b) avoidance of lower than recommended glyphosate rates; (c) keeping soil covered with a crop or legume at intercrop intervals; (d) keeping machinery free of weed seeds; and (d) use of a preplant nonselective herbicide plus residuals to eliminate early weed interference with the crop and to minimize escapes from later applications of glyphosate due to natural resistance of older weeds and/or incomplete glyphosate coverage.

  14. Review of mammalogical research in the Guianas of northern South America.

    Science.gov (United States)

    Lim, Burton K

    2016-03-01

    Research on mammals in the Guianas of northern South America has had a checkered history. In this review, I summarize the notable contributions to mammalogical study in Guyana, Suriname and French Guiana. These studies began in the mid-18th century with the binomial nomenclature system of scientific classification created by the Swedish naturalist Carl Linnaeus, who described 23 species new to science based on holotype specimens from the Guianas. Notwithstanding popular accounts by amateur naturalists visiting this region, over the next 7 decades there was only sporadic taxonomic work done on Guianan mammals primarily by researchers at European museums. The first comprehensive biological exploration took place in the 1840s during a geographic survey of the boundaries of British Guiana. However, it was not until almost half a century later that scientific publications began to regularly document the increasing species diversity in the region, including the prodigious work of Oldfield Thomas at the British Museum of Natural History in London. Another lull in the study of mammals occurred in the mid-1910s to the early 1960s after which foreign researchers began to rediscover the Guianas and their pristine habitats. This biological renaissance is still ongoing and I give a prospectus on the direction of future research in one of the last frontiers of tropical rainforest. An initiative that would be greatly beneficial is the establishment of a university network in the Guianas with graduate-based research to develop a cadre of professional experts on biodiversity and evolution as seen in other countries of South America. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  15. The Role of Satellite Imagery to Improve Pastureland Estimates in South America

    Science.gov (United States)

    Graesser, J.

    2015-12-01

    Agriculture has changed substantially across the globe over the past half century. While much work has been done to improve spatial-temporal estimates of agricultural changes, we still know more about the extent of row-crop agriculture than livestock-grazed land. The gap between cropland and pastureland estimates exists largely because it is challenging to characterize natural versus grazed grasslands from a remote sensing perspective. However, the impasse of pastureland estimates is set to break, with an increasing number of spaceborne sensors and freely available satellite data. The Landsat satellite archive in particular provides researchers with immense amounts of data to improve pastureland information. Here we focus on South America, where pastureland expansion has been scrutinized for the past few decades. We explore the challenges of estimating pastureland using temporal Landsat imagery and focus on key agricultural countries, regions, and ecosystems. We focus on the suggested shift of pastureland from the Argentine Pampas to northern Argentina, and the mixing of small-scale and large-scale ranching in eastern Paraguay and how it could impact the Chaco forest to the west. Further, the Beni Savannahs of northern Bolivia and the Colombian Llanos—both grassland and savannah regions historically used for livestock grazing—have been hinted at as future areas for cropland expansion. There are certainly environmental concerns with pastureland expansion into forests; but what are the environmental implications when well-managed pasture systems are converted to intensive soybean or palm oil plantation? Tropical, grazed grasslands are important habitats for biodiversity, and pasturelands can mitigate soil erosion when well managed. Thus, we must improve estimates of grazed land before we can make informed policy and conservation decisions. This talk presents insights into pastureland estimates in South America and discusses the feasibility to improve current

  16. Future hydroclimatological changes in South America based on an ensemble of regional climate models

    Science.gov (United States)

    Zaninelli, Pablo G.; Menéndez, Claudio G.; Falco, Magdalena; López-Franca, Noelia; Carril, Andrea F.

    2018-05-01

    Changes between two time slices (1961-1990 and 2071-2100) in hydroclimatological conditions for South America have been examined using an ensemble of regional climate models. Annual mean precipitation (P), evapotranspiration (E) and potential evapotranspiration (EP) are jointly considered through the balances of land water and energy. Drying or wetting conditions, associated with changes in land water availability and atmospheric demand, are analysed in the Budyko space. The water supply limit (E limited by P) is exceeded at about 2% of the grid points, while the energy limit to evapotranspiration (E = EP) is overall valid. Most of the continent, except for the southeast and some coastal areas, presents a shift toward drier conditions related to a decrease in water availability (the evaporation rate E/P increases) and, mostly over much of Brazil, to an increase in the aridity index (V = EP/P). These changes suggest less humid conditions with decreasing surface runoff over Amazonia and the Brazilian Highlands. In contrast, Argentina and the coasts of Ecuador and Peru are characterized by a tendency toward wetter conditions associated with an increase of water availability and a decrease of aridity index, primarily due to P increasing faster than both E and EP. This trend towards wetter soil conditions suggest that the chances of having larger periods of flooding and enhanced river discharges would increase over parts of southeastern South America. Interannual variability increases with V (for a given time slice) and with climate change (for a given aridity regimen). There are opposite interannual variability responses to the cliamte change in Argentina and Brazil by which the variability increases over the Brazilian Highlands and decreases in central-eastern Argentina.

  17. Evaluating uncertainties in regional climate simulations over South America at the seasonal scale

    Energy Technology Data Exchange (ETDEWEB)

    Solman, Silvina A. [Centro de Investigaciones del Mar y la Atmosfera CIMA/CONICET-UBA, DCAO/FCEN, UMI-IFAECI/CNRS, CIMA-Ciudad Universitaria, Buenos Aires (Argentina); Pessacg, Natalia L. [Centro Nacional Patagonico (CONICET), Puerto Madryn, Chubut (Argentina)

    2012-07-15

    This work focuses on the evaluation of different sources of uncertainty affecting regional climate simulations over South America at the seasonal scale, using the MM5 model. The simulations cover a 3-month period for the austral spring season. Several four-member ensembles were performed in order to quantify the uncertainty due to: the internal variability; the definition of the regional model domain; the choice of physical parameterizations and the selection of physical parameters within a particular cumulus scheme. The uncertainty was measured by means of the spread among individual members of each ensemble during the integration period. Results show that the internal variability, triggered by differences in the initial conditions, represents the lowest level of uncertainty for every variable analyzed. The geographic distribution of the spread among ensemble members depends on the variable: for precipitation and temperature the largest spread is found over tropical South America while for the mean sea level pressure the largest spread is located over the southeastern Atlantic Ocean, where large synoptic-scale activity occurs. Using nudging techniques to ingest the boundary conditions reduces dramatically the internal variability. The uncertainty due to the domain choice displays a similar spatial pattern compared with the internal variability, except for the mean sea level pressure field, though its magnitude is larger all over the model domain for every variable. The largest spread among ensemble members is found for the ensemble in which different combinations of physical parameterizations are selected. The perturbed physics ensemble produces a level of uncertainty slightly larger than the internal variability. This study suggests that no matter what the source of uncertainty is, the geographical distribution of the spread among members of the ensembles is invariant, particularly for precipitation and temperature. (orig.)

  18. Subduction zone locking, strain partitioning, intraplate deformation and their implications to Seismic Hazards in South America

    Science.gov (United States)

    Galgana, G. A.; Mahdyiar, M.; Shen-Tu, B.; Pontbriand, C. W.; Klein, E.; Wang, F.; Shabestari, K.; Yang, W.

    2014-12-01

    We analyze active crustal deformation in South America (SA) using published GPS observations and historic seismicity along the Nazca Trench and the active Ecuador-Colombia-Venezuela Plate boundary Zone. GPS-constrained kinematisc models that incorporate block and continuum techniques are used to assess patterns of regional tectonic deformation and its implications to seismic potential. We determine interplate coupling distributions, fault slip-rates, and intraplate crustal strain rates in combination with historic earthquakes within 40 seismic zones crust to provide moment rate constraints. Along the Nazca subduction zone, we resolve a series of highly coupled patches, interpreted as high-friction producing "asperities" beneath the coasts of Ecuador, Peru and Chile. These include areas responsible for the 2010 Mw 8.8 Maule Earthquake and the 2014 Mw 8.2 Iquique Earthquake. Predicted tectonic block motions and fault slip rates reveal that the northern part of South America deforms rapidly, with crustal fault slip rates as much as ~20 mm/a. Fault slip and locking patterns reveal that the Oca Ancón-Pilar-Boconó fault system plays a key role in absorbing most of the complex eastward and southward convergence patterns in northeastern Colombia and Venezuela, while the near-parallel system of faults in eastern Colombia and Ecuador absorb part of the transpressional motion due to the ~55 mm/a Nazca-SA plate convergence. These kinematic models, in combination with historic seismicity rates, provide moment deficit rates that reveal regions with high seismic potential, such as coastal Ecuador, Bucaramanga, Arica and Antofagasta. We eventually use the combined information from moment rates and fault coupling patterns to further constrain stochastic seismic hazard models of the region by implementing realistic trench rupture scenarios (see Mahdyiar et al., this volume).

  19. Rock art at the pleistocene/holocene boundary in Eastern South America.

    Science.gov (United States)

    Neves, Walter A; Araujo, Astolfo G M; Bernardo, Danilo V; Kipnis, Renato; Feathers, James K

    2012-01-01

    Most investigations regarding the first americans have primarily focused on four themes: when the New World was settled by humans; where they came from; how many migrations or colonization pulses from elsewhere were involved in the process; and what kinds of subsistence patterns and material culture they developed during the first millennia of colonization. Little is known, however, about the symbolic world of the first humans who settled the New World, because artistic manifestations either as rock-art, ornaments, and portable art objects dated to the Pleistocene/Holocene transition are exceedingly rare in the Americas. Here we report a pecked anthropomorphic figure engraved in the bedrock of Lapa do Santo, an archaeological site located in Central Brazil. The horizontal projection of the radiocarbon ages obtained at the north profile suggests a minimum age of 9,370 ± 40 BP, (cal BP 10,700 to 10,500) for the petroglyph that is further supported by optically stimulated luminescence (OSL) dates from sediment in the same stratigraphic unit, located between two ages from 11.7 ± 0.8 ka BP to 9.9 ± 0.7 ka BP. These data allow us to suggest that the anthropomorphic figure is the oldest reliably dated figurative petroglyph ever found in the New World, indicating that cultural variability during the Pleistocene/Holocene boundary in South America was not restricted to stone tools and subsistence, but also encompassed the symbolic dimension.

  20. Effects of mapped variation in soil conditions on estimates of soil carbon and nitrogen stocks for South America

    NARCIS (Netherlands)

    Batjes, N.H.

    2000-01-01

    Organic carbon and total nitrogen stocks for South America are computed using four 1:5,000,000 scale soil data sets of different spatial resolution. These are the 60' by 60' resolution Zobler soil data file, the 30' by 30' resolution World Inventory of Soil Emission Potentials (WISE) database, a 5'

  1. Economic prospects and policy framework of forest biotechnology in the Southern U.S.A. and South America

    Science.gov (United States)

    Frederick W. Cubbage; David N. Wear; Zohra Bennadji

    2005-01-01

    An economic framework is presented for analyzing forest biotechnology with a focus on the case of transgenic forest trees in the southeastern U.S., Uruguay, and South America. Prospective economic benefits of forest biotechnology could reach hundreds of millions of dollars per year, but greatly increased research expenditures will also be required to achieve this...

  2. Environmental controls on the distribution and diversity of lentic Chironomidae (Insecta: Diptera) across an altitudinal gradient in tropical South America

    NARCIS (Netherlands)

    Matthews-Bird, F.; Gosling, W.D.; Coe, A.L.; Bush, M.; Mayle, F.E.; Axford, Y.; Brooks, S.J.

    To predict the response of aquatic ecosystems to future global climate change, data on the ecology and distribution of keystone groups in freshwater ecosystems are needed. In contrast to mid- and high-latitude zones, such data are scarce across tropical South America (Neotropics). We present the

  3. The presence of species of Pseudochironomus Malloch 1915 (Diptera: Chironomidae) in watercourses of Chaco Serrano Ecoregion (Argentina, South America).

    Science.gov (United States)

    Paggi, Analía C; Rodriguez Garay, Gretel N

    2015-05-15

    Male imagos of Pseudochironomus viridis (Kieffer) are redescribed, the immature stages are described and figured for the first time. During this study, larva and pupal exuviae associated to P. richardsoni (Malloch) were recorded for the first time for South America. The specimens were collected from a stream and a river in the Pampasic Hills System in the Chaco Serrano ecoregion of Argentina.

  4. CULTURE STUDIES ON THE LIFE-HISTORY OF CHORDARIA-LINEARIS (PHAEOPHYCEAE) FROM TIERRA-DEL-FUEGO, SOUTH-AMERICA

    NARCIS (Netherlands)

    PETERS, AF

    1992-01-01

    Studies of laboratory cultures of Chordaria linearis (Hooker et Harvey) Cotton from southernmost South America revealed that this species has an obligate sexual life history in which a macroscopic sporophyte alternates with a monoecious microscopic gametophyte. Sexual reproduction is isogamous and

  5. Overweight and obesity: a review of their relationship to metabolic syndrome, cardiovascular disease, and cancer in South America.

    Science.gov (United States)

    Aballay, Laura R; Eynard, Aldo R; Díaz, María del Pilar; Navarro, Alicia; Muñoz, Sonia E

    2013-03-01

    Socioeconomic and demographic transformations are occurring very rapidly in some areas of the world, especially in South America, and are accompanied by changes in lifestyle, dietary patterns, and the epidemiological profile of prevalent diseases. This review examines whether obesity and overweight are related to metabolic syndrome, cardiovascular disease, and cancer in South America. Research carried out in more than 6,000 cases and controls was evaluated, along with most of the available publications related to South America. In South America, obesity and risk factors for cardiovascular disease are related mainly to aging, ethnicity effects, and preventable risky lifestyle conditions. Most of the studies that found an association between cancer and obesity are from the Southern Cone, the geographic area most affected by this pathology. Overall, the prevalence of metabolic syndrome was highest in Chile, followed in decreasing order by Colombia, Peru, Argentina, and Ecuador, with differences noted between urban and rural areas or between urban and periurban areas. Obesity and cancer may be preventable, at least in part, by healthy behavior; hence, exercise, weight control, and healthy dietary habits are important to reduce the risk of these major chronic diseases. © 2013 International Life Sciences Institute.

  6. Climate variability and human impact on the environment in South America during the last 2000 years: synthesis and perspectives

    NARCIS (Netherlands)

    Flantua, S.G.A.; Hooghiemstra, H.; Vuillle, M.; Behling, H.; Carson, J.F.; Gosling, W.D.; Hoyos, I.; Ledru, M.P.; Montoya, E.; Mayle, F.; Maldonado, A.; Rull, V.; Tonello, M.S.; Whiyney, B.S.; González-Arango, C.

    2015-01-01

    An improved understanding of present-day climate variability and change relies on high-quality data sets from the past two millennia. Global efforts to reconstruct regional climate modes are in the process of validating and integrating paleo-proxies. For South America, however, the full potential of

  7. Ranking Business and Economics Journals in South America Using the Scientific Electronic Library Online (SciELO)

    Science.gov (United States)

    Alexander, Jennifer K.; Pradenas, Lorena; Parada, Victor; Scherer, Robert F.

    2012-01-01

    Access to published research for knowledge creation and education in the administrative science disciplines in South America has been enhanced since the introduction of the Scientific Electronic Library Online (SciELO). Although SciELO has been available as an online journal indexing and publication service since 1998, there have been no…

  8. Brazilian peppertree (Schinus terebinthifolius) in Florida and South America: Evidence of a possible niche shift driven by hybridization

    Science.gov (United States)

    Brazilian peppertree (Schinus terebinthifolius Raddi, Anacardiaceae) was introduced into Florida from South America in the 1800s and commercialized as an ornamental plant. Based on herbaria records and available literature, it began to escape cultivation and invade ruderal and natural habitats in t...

  9. Over-harvesting driven by consumer demand leads to population decline: big-leaf mahogany in South America

    Science.gov (United States)

    James Grogan; Arthur G. Blundell; R. Matthew Landis; Ani Youatt; Raymond E. Gullison; Martha Martinez; Roberto Kometter; Marco Lentini; Richard E. Rice

    2010-01-01

    Consumer demand for the premier neotropical luxury timber, big-leaf mahogany (Swietenia macrophylla), has driven boom-and-bust logging cycles for centuries, depleting local and regional supplies from Mexico to Bolivia. We revise the standard historic range map for mahogany in South America and estimate the extent to which commercial stocks have been depleted using...

  10. Virtually full-length subtype F and F/D recombinant HIV-1 from Africa and South America

    NARCIS (Netherlands)

    Laukkanen, T.; Carr, J. K.; Janssens, W.; Liitsola, K.; Gotte, D.; McCutchan, F. E.; Op de Coul, E.; Cornelissen, M.; Heyndrickx, L.; van der Groen, G.; Salminen, M. O.

    2000-01-01

    For reliable classification of HIV-1 strains appropriate reference sequences are needed. The HIV-1 genetic subtype F has a wide geographic spread, causing significant epidemics in South America, Africa, and some regions of Europe. Previously only two full-length sequences of each of the HIV-1

  11. Molecular paleoparasitological diagnosis of Ascaris sp. from coprolites: new scenery of ascariasis in pre-Colombian South America times

    Directory of Open Access Journals (Sweden)

    Daniela Leles

    2008-02-01

    Full Text Available Paleoparasitological studies using microscopy showed that Ascarisand Trichuris trichiura are the human intestinal parasites most found in archaeological sites. However, in pre-Columbian South American archaeological sites, Ascaris is rare. In this work we standardized a molecular methodology for Ascaris diagnosis directly from ancient DNA retrieved from coprolites. Using cythochrome b gene (142 bp target, ancient DNA sequences were retrieved from South American samples, negative by microscopy. Moreover, the methodology applied was sensitive enough to detect ancient DNA extracted from 30 Ascaris eggs from an European coprolite. These results revealed a new scenery for the paleodistribution of Ascaris in South America.

  12. Benefits of Sharing Information: Supermodel Ensemble and Applications in South America

    Science.gov (United States)

    Dias, P. L.

    2006-05-01

    A model intercomparison program involving a large number of academic and operational institutions has been implemented in South America since 2003, motivated by the SALLJEX Intercomparison Program in 2003 (a research program focused on the identification of the role of the Andes low level jet moisture transport from the Amazon to the Plata basin) and the WMO/THORPEX (www.wmo.int/thorpex) goals to improve predictability through the proper combination of numerical weather forecasts. This program also explores the potential predictability associated with the combination of a large number of possible scenarios in the time scale of a few days to up to 15 days. Five academic institutions and five operational forecasting centers in several countries in South America, 1 academic institution in the USA, and the main global forecasting centers (NCEP, UKMO, ECMWF) agreed to provide numerical products based on operational and experimental models. The metric for model validation is concentrated on the fit of the forecast to surface observations. Meteorological data from airports, synoptic stations operated by national weather services, automatic data platforms maintained by different institutions, the PIRATA buoys etc are all collected through LDM/NCAR or direct transmission. Approximately 40 models outputs are available on a daily basis, twice a day. A simple procedure based on data assimilation principles was quite successful in combining the available forecasts in order to produce temperature, dew point, wind, pressure and precipitation forecasts at station points in S. America. The procedure is based on removing each model bias at the observational point and a weighted average based on the mean square error of the forecasts. The base period for estimating the bias and mean square error is of the order of 15 to 30 days. Products of the intercomparison model program and the optimal statistical combination of the available forecasts are public and available in real time (www

  13. Adapting to Climate Change: Reconsidering the Role of Protected Areas and Protected Organisms in Western North America

    Science.gov (United States)

    Graumlich, L. J.; Cross, M. S.; Hilty, J.; Berger, J.

    2007-12-01

    With the recent publication of the 2007 Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), little doubt remains among scientists that the global climate system is changing due to human influence and that climate change will have far-reaching and fundamental impacts on ecosystems and biodiversity. Arguably the best-documented evidence linking 20th Century warming trends to changes in physical and biological systems comes from the mountains of western North America (e.g., Figure SPM1 in Summary of Working Group 11 Report). In the West, ecosystem impacts include changes in the distribution of species as well as changing functional linkages between species such as the synchrony between flower emergence and pollinating insects. These climate impacts, when combined with other environmental stressors (e.g., altered disturbance regimes, land-use change and habitat fragmentation) portend an amplification of species extinction rates. One of the great challenges in adapting to climate change is developing and implementing policies that enhance ecological resilience in the face of these change. Clearly, the current system of nature reserves in Western North America is a fundamental asset for maintaining biodiversity and ecosystem services. However, the fixed- boundary nature of these protected areas presents a problem as species' ranges shift with future climate change. The loss of species whose ranges move outside of fixed park boundaries and the arrival of other species that move into protected areas could lead to significant turnover of species diversity, new species assemblages, and altered functionality. In short, reserves that were designed to protect particular species or communities may no longer serve their intended purpose under a changing climate. In this talk, we use case studies from the Greater Yellowstone Ecosystem and the Sonoran Desert Ecosystem to define strategies for enhancing ecological resilience to climate change at

  14. Review of literature on climate change and forest diseases of western North America

    Science.gov (United States)

    John T. Kliejunas; Brian W. Geils; Jessie Micales Glaeser; Ellen Michaels Goheen; Paul Hennon; Mee-Sook Kim; Harry Kope; Jeff Stone; Rona Sturrock; Susan J. Frankel

    2009-01-01

    A summary of the literature on relationships between climate and various types of tree diseases, and the potential effects of climate change on pathogens in western North American forests is provided. Climate change generally will lead to reductions in tree health and will improve conditions for some highly damaging pathogens. Sections on abiotic diseases, declines,...

  15. An air quality assessment in the industrialised western Bushveld Igneous Complex, South Africa

    Directory of Open Access Journals (Sweden)

    Andrew D. Venter

    2012-09-01

    Full Text Available South Africa has the largest industrialised economy in Africa, with significant mining and metallurgical activities. A large fraction of the South African mineral assets is concentrated in the Bushveld Igneous Complex (BIC, with the western limb being the most exploited. Because the majority of the world’s platinum is produced in the BIC, this area is also of international interest. There are some indications that the western BIC should be considered an air pollution hotspot; however, inadequate data exist to substantiate these claims scientifically. To partially address this knowledge gap, a comprehensive air quality monitoring station was operated for more than 2 years in this area. Meteorological parameters, trace gas concentrations and total mass concentration of particulate matter up to 10 µm in size (PM10 were measured. Compared with South African and European ambient air quality standards, SO2, NO2 and CO concentrations were generally acceptable. The major sources of SO2 were identified as high-stack industry emissions, while household combustion from semi-formal and informal settlements was identified as the predominant source of NO2 and CO. In contrast, O3 exceeded the 8-h moving average more than 322 times per year. The main contributing factor was identified to be the influx of regional air masses, with high O3 precursor concentrations. PM10 exceeded the current South African 24-h standard 6.6 times per year, the future (2015 standard 42.3 times per year and the European standard more than 120 times per year. The main source of PM10 was identified as household combustion from semi-formal and informal settlements. The findings clearly indicate that atmospheric O3 and PM10 levels in the western BIC need to be addressed to avoid negative environmental and human health impacts.

  16. Fossil woods of Detarioideae subfamily (Fabaceae) from El Palmar Formation (Late Pleistocene) in South America

    Science.gov (United States)

    Ramos, R. Soledad; Brea, Mariana; Kröhling, Daniela M.

    2017-11-01

    The main aim of the present paper is to describe the first Detarioideae fossil woods from El Palmar Formation (Late Pleistocene) in the Uruguay River Basin (Entre Ríos, Argentina). This study is based on five silicified wood specimens preserved in fluvial deposits, which were transported from their growth site. Two new genera and species are described: Paraoxystigma concordiensis gen. nov and sp. nov. has medium-sized vessels, paratracheal axial parenchyma, heterocellular and multiseriate rays, and diffuse axial canals similar in size and shape to vessels, and Gossweilerodendroxylon palmariensis gen. nov and sp. nov. has medium-sized vessels, alternate intervessel pits, paratracheal and apotracheal axial parenchyma, homocellular and uni to-multiseriate rays, and small diffuse axial canals. These Detarioideae fossil records in south-eastern South America support the existence of a very old relationship with the extant West African forests. Eco-anatomical features observed in these fossil woods, along with the climatic information available from the Nearest Living Relatives (NLRs) comparison, suggest warm and humid climatic conditions for the upper-middle basin of the Uruguay River during some periods of the Late Pleistocene.

  17. [Can informal employment be compared in South America? Analysis of its definition, measurement and classification].

    Science.gov (United States)

    Ruiz, Marisol E; Tarafa Orpinell, Gemma; Jódar Martínez, Pere; Benach, Joan

    2015-01-01

    To characterize and analyze the situation of informal employment with regard to its definition, measurement and classification in South American countries. A literature review was conducted from four databases and grey literature through a scoping review, which included reports from international organizations and from the 12 countries in South America. The data were analyzed by evaluating content and establishing similarities among countries. The data reviewed showed a disparity in the definitions used, although many countries define informal employment as workers with no contract. Most countries measured informal employment through household surveys, but due to the differences in classifications, the information found was heterogeneous, with little standardization among registries. Therefore, the data could not be compared at a regional level. The definition of the International Labour Organization was not useful to study informal employment in the countries studied. The definition should include protected and unprotected workers. An appropriate and specific definition of informal employment would allow nuances to be studied within the concept, revealing the loopholes faced by most of the population working informally. The key to meaningful comparisons within the study region is to incorporate common indicators among local registration systems (measurement) in order to determine the public health impact in the informally employed population. Copyright © 2014 SESPAS. Published by Elsevier Espana. All rights reserved.

  18. A Taxonomic Update of Small Mammal Plague Reservoirs in South America.

    Science.gov (United States)

    Bonvicino, Cibele R; Oliveira, João A; Cordeiro-Estrela, Pedro; D'andrea, Paulo S; Almeida, Alzira M P

    2015-10-01

    Plague is a disease of epidemic potential that may emerge with discontinuous outbreaks. In South America, 50 wild rodent species have been identified as plague reservoirs, in addition to one lagomorph and two marsupials. To review the nomenclature of plague reservoirs, we examined specimens collected in plague foci, carried out new surveys in Brazilian plague regions, and re-evaluated the nomenclature of South American reservoirs on the basis of the current literature. Five of the 15 species involved with plague in Argentina, three of 10 species involved with plague in Bolivia, three of the seven species involved with plague in Peru, five of the nine species involved with plague in Ecuador, and six of the nine species involved with plague in Brazil have undergone taxonomic changes. In the last 20 years, plague cases were recorded in Bolivia, Brazil, Ecuador, and Peru. These four countries have a high rodent species richness in plague foci, a fact that may be decisive for the maintenance of plague in the wild.

  19. Restructuring the oil segment in South America: public policy, private capital and energy integration

    International Nuclear Information System (INIS)

    Fiorotti, A.; Tiomno Tolmasquim, M.; Tiomno Tolmasquim, M.; Alveal, C.

    2006-01-01

    The World Oil Industry (WOI) developed through two types of economic organization, built up around vertically integrated and internationalized enterprises: the US model, based on private international firms, and the model centered on setting up State-run enterprises, initially in the United Kingdom, Argentina and Mexico. However, from the first oil crisis (1973) onwards, the World Oil Industry has gradually been un-bundled through nationalization and the loss of control over the reserves by the oil majors. With this new configuration of the industry, from the 1980's onwards, the strategies of the major international oil companies focused on developing the spot market, while lowering investment and operating costs, introducing correlated diversification strategies, and enhancing industrial concentration through mergers and acquisitions and/or cooperation agreements between companies. The core purpose of these strategic shifts is to obtain control over new oil field areas. The restructuring processes of national oil industries all over the world - particularly in South America - constituted an important drive aligned with these new guidelines, headed up by the global oil operators. This paper analyzes the changes in the South American oil sector during the 1990's, analyzing aspects involved in awarding mineral rights in the upstream segment. Despite similar policies, market deregulation processes follow different patterns. However, the most significant aspect is an increase in the presence of international private capital in the dynamics of this sector, mainly in regional energy integration processes. (authors)

  20. Extreme rainfall, vulnerability and risk: a continental-scale assessment for South America

    Science.gov (United States)

    Vorosmarty, Charles J.; de Guenni, Lelys Bravo; Wollheim, Wilfred M.; Pellerin, Brian A.; Bjerklie, David M.; Cardoso, Manoel; D'Almeida, Cassiano; Colon, Lilybeth

    2013-01-01

    Extreme weather continues to preoccupy society as a formidable public safety concern bearing huge economic costs. While attention has focused on global climate change and how it could intensify key elements of the water cycle such as precipitation and river discharge, it is the conjunction of geophysical and socioeconomic forces that shapes human sensitivity and risks to weather extremes. We demonstrate here the use of high-resolution geophysical and population datasets together with documentary reports of rainfall-induced damage across South America over a multi-decadal, retrospective time domain (1960–2000). We define and map extreme precipitation hazard, exposure, affectedpopulations, vulnerability and risk, and use these variables to analyse the impact of floods as a water security issue. Geospatial experiments uncover major sources of risk from natural climate variability and population growth, with change in climate extremes bearing a minor role. While rural populations display greatest relative sensitivity to extreme rainfall, urban settings show the highest rates of increasing risk. In the coming decades, rapid urbanization will make South American cities the focal point of future climate threats but also an opportunity for reducing vulnerability, protecting lives and sustaining economic development through both traditional and ecosystem-based disaster risk management systems.

  1. USING SRTM TO QUANTIFY SIZE PARAMETERS AND SPATIAL DISTRIBUTION OF ENDORHEIC BASINS IN SOUTHERN SOUTH AMERICA

    Directory of Open Access Journals (Sweden)

    Ralf Hesse

    2008-08-01

    Full Text Available The SRTM data set is the highest resolution DEM with global or continental coverage. It is therefore theDEM of choice for continental-scale geomorphological mapping and quantitative analysis. In this study,SRTM data are used for the identification and characterisation of endorheic basins in southern SouthAmerica (south of 19°S. The results show the feasibility of continental-scale quantitative geomorphologybased on SRTM data and provide insights into the distribution of closed basins. The largest endorheicbasin is located in the Puna region and consists of several interconnected sub-basins. This basin accountsfor 38.6 % (7877 km3 of the total volume of the endorheic basins identified in this study. Analyses of thegeographic distribution show a narrow longitudinal distribution between 64.5 and 71.5° W and a multimodallatitudinal distribution which is characterised by two groups of basins at 22.5–27.5°S and 37.5–50.0° Sand an almost complete absence of basins between 27.5 and 37.5° S. Problems and sources ofmisinterpretation arising from data quality and resolution are discussed. Further research, targeting in particularthe genesis and potential for paleoenvironmental reconstruction of closed basins in southern Argentina, iscalled for.

  2. Extreme rainfall, vulnerability and risk: a continental-scale assessment for South America.

    Science.gov (United States)

    Vörösmarty, Charles J; Bravo de Guenni, Lelys; Wollheim, Wilfred M; Pellerin, Brian; Bjerklie, David; Cardoso, Manoel; D'Almeida, Cassiano; Green, Pamela; Colon, Lilybeth

    2013-11-13

    Extreme weather continues to preoccupy society as a formidable public safety concern bearing huge economic costs. While attention has focused on global climate change and how it could intensify key elements of the water cycle such as precipitation and river discharge, it is the conjunction of geophysical and socioeconomic forces that shapes human sensitivity and risks to weather extremes. We demonstrate here the use of high-resolution geophysical and population datasets together with documentary reports of rainfall-induced damage across South America over a multi-decadal, retrospective time domain (1960-2000). We define and map extreme precipitation hazard, exposure, affectedpopulations, vulnerability and risk, and use these variables to analyse the impact of floods as a water security issue. Geospatial experiments uncover major sources of risk from natural climate variability and population growth, with change in climate extremes bearing a minor role. While rural populations display greatest relative sensitivity to extreme rainfall, urban settings show the highest rates of increasing risk. In the coming decades, rapid urbanization will make South American cities the focal point of future climate threats but also an opportunity for reducing vulnerability, protecting lives and sustaining economic development through both traditional and ecosystem-based disaster risk management systems.

  3. Historical Biogeography of Five Characidium Fish Species: Dispersal from the Amazon Paleobasin to Southeastern South America.

    Science.gov (United States)

    Poveda-Martínez, Daniel; Sosa, Chrystian C; Chacón-Vargas, Katherine; García-Merchán, Víctor Hugo

    2016-01-01

    Characidium is a Neotropical fish genus. Its distribution ranges from eastern Panama to northern Argentina, and it is an important component of the Neotropical ichthyofauna present in the major rivers of South America. We here provide an approximation to the dispersal and historical distributions of Characidium. The biogeographic history of five species of the genus was analyzed through nuclear RAG-2 and mitochondrial 16S genes and a time-calibrated phylogenetic analysis using three outgroup species. A biogeographical reconstruction was performed to estimate ancestral geographic ranges and infer the historical events that impacted the geographic distributions of Characidium species. Our results showed Characidium as a monophyletic group. The molecular clock suggests that the most recent common ancestor of Characidium originated during the Eocene, about 50.2 Mya. In addition, different dispersion and vicariance events could be inferred, which possibly gave rise to the present geographical distribution of the genus. Our results point to the rise of the Andean mountains and sea fluctuations as being important events in the formations and delimitation of different rivers, which influenced the distribution of South American ichthyofauna.

  4. Hans Kelsen – The Reception of “Pure Theory” in South America, Particularly in Brazil

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo de Abreu Boucault

    2015-12-01

    Full Text Available This article aims to examine the reception of « Pure theory of Law », of Hans Kelsen in some South-American countries, throughout institutional approaches and also the diffusion of this theory as well its acceptance by cultural agents who represented academic and professional law environment, in Uruguay, Colombia, Argentina and Brazil. The historical period of this study concerns the early times of 40 till our days. Although the reference of Kelsen’s thought about theory of law may appear as a constant feature on South-American jurists, mainly till the decade of 1980, actually we can identify real problems that claim for a falsehood about the guidelines of the pure theory of law and ambiguities in connection to theoretical issues within positivist traditions in face of authoritarian governments in Latin America.

  5. Ancient mitochondrial DNA reveals convergent evolution of giant short-faced bears (Tremarctinae) in North and South America.

    Science.gov (United States)

    Mitchell, Kieren J; Bray, Sarah C; Bover, Pere; Soibelzon, Leopoldo; Schubert, Blaine W; Prevosti, Francisco; Prieto, Alfredo; Martin, Fabiana; Austin, Jeremy J; Cooper, Alan

    2016-04-01

    The Tremarctinae are a subfamily of bears endemic to the New World, including two of the largest terrestrial mammalian carnivores that have ever lived: the giant, short-faced bears Arctodus simus from North America and Arctotherium angustidens from South America (greater than or equal to 1000 kg). Arctotherium angustidens became extinct during the Early Pleistocene, whereas Arctodus simus went extinct at the very end of the Pleistocene. The only living tremarctine is the spectacled bear (Tremarctos ornatus), a largely herbivorous bear that is today only found in South America. The relationships among the spectacled bears (Tremarctos), South American short-faced bears (Arctotherium) and North American short-faced bears (Arctodus) remain uncertain. In this study, we sequenced a mitochondrial genome from an Arctotherium femur preserved in a Chilean cave. Our molecular phylogenetic analyses revealed that the South American short-faced bears were more closely related to the extant South American spectacled bear than to the North American short-faced bears. This result suggests striking convergent evolution of giant forms in the two groups of short-faced bears (Arctodus and Arctotherium), potentially as an adaptation to dominate competition for megafaunal carcasses. © 2016 The Author(s).

  6. A new perspective on the regional hydrologic cycle over North and South America

    Science.gov (United States)

    Weng, Shu-Ping

    The GEOS-1 vertically-integrated 3-hr moisture flux reanalyses and hourly-gridded United States station precipitation plus a satellite-based, 6-hr global precipitation estimate were employed to investigate the impacts of nocturnal low-level jets (LLJs) on the regional hydrological cycle over the central United States (Part I) and the subtropical plains of South America (Part II). Research stressed the influences of upper-level synoptic-scale waves (i.e., synoptic-scale forcings) upon the regional hydrologic processes, which were explored by the impacts associated with the occurrence of LLJ. Besides the conventional budget analysis, the adopted `synoptic-forcing approach' was proven illustrative in describing these impacts through the down-scaling process of LLJs. In Part 1, the major findings include: (1)the seasonal-averaged hydrological cycle over the Great Plains is strongly affected by the occurrence of GPLLJ, (2)the synoptic-scale forcing provided by the upper-level propagating jet (ULJ) streams is essential in generating the large-scale precipitation after the GPLLJ forms from the diurnal boundary layer process, (3)without the dynamic coupling between the ULJ and LLJ, the impact of LLJ on the hydrological cycle is demonstrated to be less important, and (4)the importance of synoptic-scale forcings in preconditioning the setting of wet/dry seasons in the interannual variability of rainfall anomaly is further illustrated by examining the changes of intensity as well as the occurrence frequency between the different types of LLJ. In Part II of this study, it was found that the occurrence of Andean LLJ represents a transient episode that detours the climatic rainfall activity along the South Atlantic Convergent Zone (SACZ) to the subtropical plains (Brazilian Nordeste) in its southwestern (northeastern) flank. The appearance of a seesaw pattern in the rainfall and flux convergence anomalies along the southeastern portion of South America, which is spatially in

  7. Psychiatric hospital beds and prison populations in South America since 1990: does the Penrose hypothesis apply?

    Science.gov (United States)

    Mundt, Adrian P; Chow, Winnie S; Arduino, Margarita; Barrionuevo, Hugo; Fritsch, Rosemarie; Girala, Nestor; Minoletti, Alberto; Mitkiewicz, Flávia; Rivera, Guillermo; Tavares, María; Priebe, Stefan

    2015-02-01

    In 1939, English mathematician, geneticist, and psychiatrist Lionel Sharples Penrose hypothesized that the numbers of psychiatric hospital beds and the sizes of prison populations were inversely related; 75 years later, the question arises as to whether the hypothesis applies to recent developments in South America. To explore the possible association of changes in the numbers of psychiatric hospital beds with changes in the sizes of prison populations in South America since 1990. We searched primary sources for the numbers of psychiatric hospital beds in South American countries since 1990 (the year that the Latin American countries signed the Caracas Declaration) and compared these changes against the sizes of prison populations. The associations between the numbers of psychiatric beds and the sizes of prison populations were tested using fixed-effects regression of panel data. Economic variables were considered as covariates. Sufficiently reliable and complete data were obtained from 6 countries: Argentina, Bolivia, Brazil, Chile, Paraguay, and Uruguay. The numbers of psychiatric beds and the sizes of prison populations. Since 1990, the numbers of psychiatric beds decreased in all 6 countries (ranging from -2.0% to -71.9%), while the sizes of prison populations increased substantially (ranging from 16.1% to 273.0%). Panel data regression analysis across the 6 countries showed a significant inverse relationship between numbers of psychiatric beds and sizes of prison populations. On average, the removal of 1 bed was associated with 5.18 more prisoners (95% CI, 3.10-7.26; P = .001), which was reduced to 2.78 prisoners (95% CI, 2.59-2.97; P prison populations remained practically unchanged when income inequality was considered as a covariate (-4.28 [95% CI, -5.21 to -3.36]; P prison populations have increased against a background of strong economic growth. The changes appear to be associated because the numbers of beds decreased more extensively when and

  8. Imaging the lithosphere and underlying mantle of the South Atlantic, South America and Africa using waveform tomography with massive datasets

    Science.gov (United States)

    Celli, N. L.; Lebedev, S.; Schaeffer, A. J.; Ravenna, M.; Gaina, C.

    2017-12-01

    Recent growth in global seismic station coverage has created dense data sampling of the previously poorly constrained lithosphere and underlying mantle beneath the South Atlantic, South America and Africa. The new data enable us to image the vast region at a new level of detail and address important open questions regarding its lithospheric architecture and mantle dynamics. In order to fully exploit the data sampling, we use an efficient, multimode waveform tomography scheme that enables the extraction of structural information from millions of seismograms and use the inherent data redundancy to minimize effects of errors in the data. Our tomographic model is constrained by waveform fits of over 1.2 million vertical-component seismograms, computed using the Automated Multimode Inversion of surface, S- and multiple S-waves. Each successful seismogram fit provides a set of linear equations describing 1D average velocity perturbations within approximate sensitivity volumes, with respect to a 3D reference model. We then combine all equations into a large linear system and invert jointly for a model of S- and P-wave speeds and azimuthal anisotropy within the lithosphere and underlying mantle. We are now able to image the detailed structure of various African shields. For example, in West Africa, two clearly separate high-velocity units underlay the Reguibat and Man-Léo Shields; in the Congo area, a single high-velocity body, formed by three main units correspond to the Gabon-Cameroon, Bomu-Kibali and Kasai Shields. Strong low-velocity anomalies underlay the Afar Hotspot and the East African Rift; pronounced low velocities are also seen beneath parts of the Sahara Desert. We discuss the shape of the deep Afar anomaly and its possible relationships with the Saharan volcanism and the neighboring Tanzania Craton. In the South Atlantic, we retrieve fine-scale velocity structure along the Mid-Atlantic Ridge (MAR), indicative of hotspot-ridge interactions. Major hotspots show

  9. Warm and Dry Spells (WDS in Austral Winter over Central South America

    Directory of Open Access Journals (Sweden)

    P. Satyamurty

    2007-06-01

    Full Text Available The horizontal and vertical structure of unusually warm and dry spells (WDS over the central parts of South America during the winter and post-winter months (JJAS are studied. During WDS the mean temperature and humidity anomalies over central Brazil are about +4.1°C and −13.2%, respectively. The mean duration of WDS is 11 days and their mean frequency is less than one per year during the months of JJAS. Apparently, WDS have no preference for the phase of ENSO. Widespread and persistent subsidence in the middle troposphere is observed in tropical Brazil during WDS, which renders the lower tropospheric air warm and dry. The negative anomalies of the specific humidity are observed to be associated with the subsidence regions. A strong, slow moving ridge in the eastern South Pacific and a low-pressure center in northern Argentina are important surface characteristics during the WDS. A more detailed investigation of two specific WDS events, a strong event (August–September 1999 and a moderate one (June 2002, shows a blocking-like situation in the 500-hPa geopotential and surface pressure fields in the Pacific. The South Atlantic subtropical high somewhat approaches the continent. Strong northerlies over the central and eastern parts of Brazil are also observed in the lower troposphere. During WDS the regional circulation acquires summertime characteristics, except for the absence of precipitation, and the circulation in the meridional plane is in the opposite sense from the Hadley circulation. A frontal system, supported by a 500-hPa trough, advances into central Brazil, causing the dissipation of the anomalous situation.

  10. Australian doctors and the visual arts. Part 5. Doctor-artists in South Australia, Tasmania, Western Australia and Queensland.

    Science.gov (United States)

    Hamilton, D G

    1986-11-17

    The contributions of Australian doctors to the visual arts are being described in a series of six articles. Work from doctors in New South Wales and Victoria has been covered previously. Now activities in South Australia, Tasmania, Western Australia, Queensland and the Northern Territory are presented.

  11. Comparison of population genetic patterns in two widespread freshwater mussels with contrasting life histories in western North America.

    Science.gov (United States)

    Mock, K E; Brim Box, J C; Chong, J P; Furnish, J; Howard, J K

    2013-12-01

    We investigate population genetic structuring in Margaritifera falcata, a freshwater mussel native to western North America, across the majority of its geographical range. We find shallow rangewide genetic structure, strong population-level structuring and very low population diversity in this species, using both mitochondrial sequence and nuclear microsatellite data. We contrast these patterns with previous findings in another freshwater mussel species group (Anodonta californiensis/A. nuttalliana) occupying the same continental region and many of the same watersheds. We conclude that differences are likely caused by contrasting life history attributes between genera, particularly host fish requirements and hermaphroditism. Further, we demonstrate the occurrence of a 'hotspot' for genetic diversity in both groups of mussels, occurring in the vicinity of the lower Columbia River drainage. We suggest that stream hierarchy may be responsible for this pattern and may produce similar patterns in other widespread freshwater species. © 2013 John Wiley & Sons Ltd.

  12. Extreme working hours in Western Europe and North America: A new aspect of polarization

    OpenAIRE

    Burger, Anna S.

    2015-01-01

    This paper analyzes the trends and root causes of extreme working hours in sixteen Western European countries, Canada, and the United States between 1970 and 2010. Earlier literature has revealed increasing trends in extreme working hours in the United States and recognized the negative repercussions of this new aspect of labor market polarization. As European average working hours have declined over the past decades, scholars have turned little attention to the analysis of extreme working ho...

  13. Regional programme for the eradication of the Carambola fruit fly in South America

    International Nuclear Information System (INIS)

    Malavasi, Aldo; Sauers-Muller, Alies van; Midgarden, David; Kellman, Victorine; Didelot, Dominique; Caplong, Phillippe; Ribeiro, Odilson

    2000-01-01

    Bactrocera carambolae Drew and Hancock, the Carambola fruit fly (CFF), was probably introduced into Suriname from Indonesia in the 1960s or 1970s. The most likely mechanism of introduction was people arriving at Suriname from Indonesia by air, through Amsterdam. Any other method of transport would be too lengthy. Air travel was not commonly available to the general Surinamese population before the 1960s. About one-fifth of the Surinamese population is of Indonesian origin, and many strong ties remained between the countries. These ties are loosening with the increasing number of generations after immigration, which occurred in the late nineteenth and early twentieth century. The first recorded Bactrocera found in Suriname was in 1975, when flies were reared from a market fruit and preserved unidentified in the Ministry of Agriculture's insect collection. Bactrocera were not recorded again until 1986, when infested fruits were brought to the attention of the Ministry by a homeowner. These specimens were sent to the United States for identification and were identified as Dacus dorsalis. B. carambolae was formally described in 1994 as a species belonging to the B. dorsalis complex (Drew and Hancock 1994). At that time, in 1986, little importance was given to the finding in the United States, perhaps because the identifier was unaware that Suriname is in South America rather than Asia. The international community would only become aware of the establishment of a Dacus/Bactrocera species in the Americas four years later. The population of flies in the Guyanas has now been identified as B. carambolae, and its establishment in South America is a threat to the production and marketing of fruits throughout the tropical and subtropical Americas and the Caribbean (Hancock 1989). It might be expected that the newly established B. carambolae would move rapidly into the tropical forests where there are many species of the native Anastrepha fruit flies and, presumably, many

  14. Interannual variability of western North Pacific SST anomalies and its impact on North Pacific and North America

    Science.gov (United States)

    Park, Jae-Heung; An, Soon-Il; Kug, Jong-Seong

    2017-12-01

    In this study, the interannual variability of sea surface temperature (SST) and its atmospheric teleconnection over the western North Pacific (WNP) toward the North Pacific/North America during boreal winter are investigated. First, we defined the WNP mode as the first empirical orthogonal function (EOF) mode of SST anomalies over the WNP region (100-165°E, 0-35°N), of which the principle component time-series are significantly correlated with several well-known climate modes such as the warm pool mode which is the second EOF mode of the tropical to North Pacific SST anomalies, North Pacific oscillation (NPO), North Pacific gyre oscillation (NPGO), and central Pacific (CP)-El Niño at 95% confidence level, but not correlated with the eastern Pacific (EP)-El Niño. The warm phase of the WNP mode (sea surface warming) is initiated by anomalous southerly winds through reduction of wind speed with the background of northerly mean winds over the WNP during boreal winter, i.e., reduced evaporative cooling. Meanwhile, the atmospheric response to the SST warming pattern and its diabatic heating further enhance the southerly wind anomaly, referred to the wind-evaporation-SST (WES) feedback. Thus, the WNP mode is developed and maintained through winter until spring, when the northerly mean wind disappears. Furthermore, it is also known that anomalous upper-level divergence associated with WNP mode leads to the NPO-like structure over the North Pacific and the east-west pressure contrast pattern over the North America through Rossby wave propagation, impacting the climate over the North Pacific and North America.

  15. Parallel Epidemics of Community-Associated Methicillin-Resistant Staphylococcus aureus USA300 Infection in North and South America.

    Science.gov (United States)

    Planet, Paul J; Diaz, Lorena; Kolokotronis, Sergios-Orestis; Narechania, Apurva; Reyes, Jinnethe; Xing, Galen; Rincon, Sandra; Smith, Hannah; Panesso, Diana; Ryan, Chanelle; Smith, Dylan P; Guzman, Manuel; Zurita, Jeannete; Sebra, Robert; Deikus, Gintaras; Nolan, Rathel L; Tenover, Fred C; Weinstock, George M; Robinson, D Ashley; Arias, Cesar A

    2015-12-15

    The community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) epidemic in the United States is attributed to the spread of the USA300 clone. An epidemic of CA-MRSA closely related to USA300 has occurred in northern South America (USA300 Latin-American variant, USA300-LV). Using phylogenomic analysis, we aimed to understand the relationships between these 2 epidemics. We sequenced the genomes of 51 MRSA clinical isolates collected between 1999 and 2012 from the United States, Colombia, Venezuela, and Ecuador. Phylogenetic analysis was used to infer the relationships and times since the divergence of the major clades. Phylogenetic analyses revealed 2 dominant clades that segregated by geographical region, had a putative common ancestor in 1975, and originated in 1989, in North America, and in 1985, in South America. Emergence of these parallel epidemics coincides with the independent acquisition of the arginine catabolic mobile element (ACME) in North American isolates and a novel copper and mercury resistance (COMER) mobile element in South American isolates. Our results reveal the existence of 2 parallel USA300 epidemics that shared a recent common ancestor. The simultaneous rapid dissemination of these 2 epidemic clades suggests the presence of shared, potentially convergent adaptations that enhance fitness and ability to spread. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  16. The metallogenic role of east-west fracture zones in South America with regard to the motion of lithospheric plates (with an example from Brazil)

    Science.gov (United States)

    Kutina, J.; Carter, William D.; Lopez, F.X.

    1978-01-01

    The role of east-west fracture zones in South America is discussed with regard to global fracturing and the motion of lithospheric plates. A set of major NW-trending lineaments has been derived which show a tendency to be spaced equidistantly and may correspond to a set of east-west fractures in the "pre-drift" position of the South American plate. Statistical analysis of linears in the ERTS-mosaics shows that NW-fractures are also among the most important ones in the Andes region, suggesting that the above major lineaments extend into the basement of the Andes. Some of the old major fractures, trending east-west in the present orientation of South America, are discussed and their NE orientation in the pre-drift position of the plate is considered. An example of structural control of ore deposition in the Brazilian Shield is presented, using the maps of the RADAM Project. It is concluded that the small tin-bearing granitic bodies concentrated in the region of Sao Felix do Xingu in the state of Para represent upper parts of an unexposed granitoid massif which is controlled by the intersection of a major east-west fracture zone probably represents westward extension of the Patos Lineament of the easternmost part of Brazil, connected with the east-west fracture zone of the Para state through the basement of the Maranhao Basin (Sineclise do Maranhao-Piaui). It is expected that the proposed "Patos-Para Lineament" extends further westward and may similarly control, at intersections with fractures of other trends, some mineralization centers in the western part of the state of Para and in the state of Amazonas.

  17. Goals and means of a sustainable energy development in Brazil and South America

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, J R [Secretariat of Science and Technology, Federal Government of Brazil (BR)

    1991-07-01

    The discussion presented in this paper deals with the amount of energy which will be necessary to guarantee South American development in a sustainable way. This issue must be considered as a compromise between the supply and demand market and significant efforts in energy planning will be necessary if a better future shall be expected for the population. We assume that 1.5 kW of energy per capita (commercial and non commercial) can be available in the region by the year 2010 and that such energy will be used with better efficiency than today. As a consequence, the average South-American's standard of living is equvalent to the standard of living of the average Western European citizen of the 1970's. Our energy forecast implies a small energy growth rate as compared with historical values for the region, but even so the amount of money required for this investment probably will not be available if a business-as-usual energy supply program will be followed. The possibility of some less cost-intensive opportunities to provide more energy will be discussed. (author).

  18. Regional and Seasonal Diet of the Western Burrowing Owl in South-Central Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Derek B. Hall, Paul D. Greger, Jeffrey R. Rosier

    2009-04-01

    We examined diets of Western Burrowing Owls (Athene cunicularia hypugaea) based on contents of pellets and large prey remains collected year-round at burrows in each of the 3 regions in south central Nevada (Mojave Desert, Great Basin Desert, and Transition region). The most common prey items, based on percent frequency of occurrence, were crickets and grasshoppers, beetles, rodents, sun spiders, and scorpions. The most common vertebrate prey was kangaroo rats (Dipodomys spp.). True bugs (Hemiptera), scorpions, and western harvest mice (Reithrodontomys megalotis) occurred most frequently in pellets from the Great Basin Desert region. Kangaroo rats (Dipodomys spp.) and pocket mice (Perognathinae) were the most important vertebrate prey items in the Transition and Mojave Desert regions, respectively. Frequency of occurrence of any invertebrate prey was high (>80%) in samples year-round but dropped in winter samples, with scorpions and sun spiders exhibiting the steepest declines. Frequency of occurrence of any vertebrate prey peaked in spring samples, was intermediate for winter and summer samples, and was lowest in fall samples. With the possible exception of selecting for western harvest mice in the Great Basin Desert region, Western Burrowing Owls in our study appeared to be opportunistic foragers with a generalist feeding strategy.

  19. A Q fever cluster among workers at an abattoir in south-western Sydney, Australia, 2015

    Directory of Open Access Journals (Sweden)

    Heidi Lord

    2016-11-01

    Full Text Available Background: In September 2015, the Public Health Unit of the South Western Sydney Local Health District was notified of two possible Q fever cases. Case investigation identified that both cases were employed at an abattoir, and both cases advised that co-workers had experienced similar symptoms. Public Health Unit staff also recalled interviewing in late 2014 at least one other Q fever case who worked at the same abattoir. This prompted an outbreak investigation. Methods: The investigation incorporated active case finding, microbiological analysis, field investigation and a risk factor survey. Included cases were laboratory definitive or suspected cases occurring from October 2014 to October 2015, residing or working in south-western Sydney. A suspected case had clinically compatible illness, high-risk exposure and was epidemiologically linked to another confirmed case. A confirmed case included laboratory detection of C. burnetii. Results: Eight cases met the case definition with seven confirmed (including a deceased case and one suspected. The eight cases were all males who had been employed at an abattoir in south-western Sydney during their incubation period; symptom onset dates ranged from November 2014 to September 2015. Field investigation identified multiple potential risk factors at the abattoir, and the majority (75% of employees were not vaccinated against Q fever despite this high-risk setting. Conclusion: This cluster of Q fever in a single abattoir confirms the significance of this zoonotic disease as an occupational hazard among persons working in high-risk environments. Implementation of Q fever vaccination programmes should eliminate Q fever in high-risk occupational settings.

  20. Landsat TM inventory and assessment of waterbird habitat in the southern altiplano of South America

    Science.gov (United States)

    Boyle, T.P.; Caziani, S.M.; Waltermire, R.G.

    2004-01-01

    The diverse set of wetlands in southern altiplano of South America supports a number of endemic and migratory waterbirds. These species include endangered endemic flamingos and shorebirds that nest in North America and winter in the altiplano. This research developed maps from nine Landsat Thematic Mapper (TM) images (254,300 km2) to provide an inventory of aquatic waterbird habitats. Image processing software was used to produce a map with a classification of wetlands according to the habitat requirements of different types of waterbirds. A hierarchical procedure was used to, first, isolate the bodies of water within the TM image; second, execute an unsupervised classification on the subsetted image to produce 300 signatures of cover types, which were further subdivided as necessary. Third, each of the classifications was examined in the light of field data and personal experience for relevance to the determination of the various habitat types. Finally, the signatures were applied to the entire image and other adjacent images to yield a map depicting the location of the various waterbird habitats in the southern altiplano. The data sets referenced with a global positioning system receiver were used to test the classification system. Multivariate analysis of the bird communities censused at each lake by individual habitats indicated a salinity gradient, and then the depth of the water separated the birds. Multivariate analysis of the chemical and physical data from the lakes showed that the variation in lakes were significantly associated with difference in depth, transparency, latitude, elevation, and pH. The presence of gravel bottoms was also one of the qualities distinguishing a group of lakes. This information will be directly useful to the Flamingo Census Project and serve as an element for risk assessment for future development.

  1. ATLANTIC BATS: a data set of bat communities from the Atlantic Forests of South America.

    Science.gov (United States)

    Muylaert, Renata D L; Stevens, Richard D; Esbérard, Carlos E L; Mello, Marco A R; Garbino, Guilherme S T; Varzinczak, Luiz H; Faria, Deborah; Weber, Marcelo D M; Kerches Rogeri, Patricia; Regolin, André L; Oliveira, Hernani F M D; Costa, Luciana D M; Barros, Marília A S; Sabino-Santos, Gilberto; Crepaldi de Morais, Mara Ariane; Kavagutti, Vinicius S; Passos, Fernando C; Marjakangas, Emma-Liina; Maia, Felipe G M; Ribeiro, Milton C; Galetti, Mauro

    2017-12-01

    Bats are the second most diverse mammal order and they provide vital ecosystem functions (e.g., pollination, seed dispersal, and nutrient flux in caves) and services (e.g., crop pest suppression). Bats are also important vectors of infectious diseases, harboring more than 100 different virus types. In the present study, we compiled information on bat communities from the Atlantic Forests of South America, a species-rich biome that is highly threatened by habitat loss and fragmentation. The ATLANTIC BATS data set comprises 135 quantitative studies carried out in 205 sites, which cover most vegetation types of the tropical and subtropical Atlantic Forest: dense ombrophilous forest, mixed ombrophilous forest, semideciduous forest, deciduous forest, savanna, steppe, and open ombrophilous forest. The data set includes information on more than 90,000 captures of 98 bat species of eight families. Species richness averaged 12.1 per site, with a median value of 10 species (ranging from 1 to 53 species). Six species occurred in more than 50% of the communities: Artibeus lituratus, Carollia perspicillata, Sturnira lilium, Artibeus fimbriatus, Glossophaga soricina, and Platyrrhinus lineatus. The number of captures divided by sampling effort, a proxy for abundance, varied from 0.000001 to 0.77 individuals·h -1 ·m -2 (0.04 ± 0.007 individuals·h -1 ·m -2 ). Our data set reveals a hyper-dominance of eight species that together that comprise 80% of all captures: Platyrrhinus lineatus (2.3%), Molossus molossus (2.8%), Artibeus obscurus (3.4%), Artibeus planirostris (5.2%), Artibeus fimbriatus (7%), Sturnira lilium (14.5%), Carollia perspicillata (15.6%), and Artibeus lituratus (29.2%). © 2017 by the Ecological Society of America.

  2. Avian Influenza Virus Isolated in Wild Waterfowl in Argentina: Evidence of a potentially unique phylogenetic lineage in South America

    Science.gov (United States)

    Pereda, Ariel J.; Uhart, Marcela; Perez, Alberto A.; Zaccagnini, Maria E.; La Sala, Luciano; Decarre, Julieta; Goijman, Andrea; Solari, Laura; Suarez, Romina; Craig, Maria I.; Vagnozzi, Ariel; Rimondi, Agustina; König, Guido; Terrera, Maria V.; Kaloghlian, Analia; Song, Haichen; Sorrell, Erin M.; Perez, Daniel R.

    2008-01-01

    Avian Influenza (AI) viruses have been sporadically isolated in South America. The most recent reports are from an outbreak in commercial poultry in Chile in 2002 and its putative ancestor from a wild bird in Bolivia in 2001. Extensive surveillance in wild birds was carried out in Argentina during 2006-2007. Using RRT-PCR, 12 AI positive detections were made from cloacal swabs. One of those positive samples yielded an AI virus isolated from a wild kelp gull (Larus dominicanus) captured in the South Atlantic coastline of Argentina. Further characterization by nucleotide sequencing reveals that it belongs to the H13N9 subtype. Phylogenetic analysis of the 8 viral genes suggests that the 6 internal genes are related to the isolates from Chile and Bolivia. The analysis also indicates that a cluster of phylogenetically related AI viruses from South America may have evolved independently, with minimal gene exchange, from influenza viruses in other latitudes. The data produced from our investigations are valuable contributions to the study of AI viruses in South America. PMID:18632129

  3. First case of New Delhi metallo-β-lactamase in Klebsiella pneumoniae from Ecuador: An update for South America.

    Science.gov (United States)

    Romero-Alvarez, Daniel; Reyes, Jorge; Quezada, Viviana; Satán, Carolina; Cevallos, Nelson; Barrera, Sofía; Trueba, Gabriel; Escobar, Luis E; Villacís, José E

    2017-12-01

    To describe a clinical case of Klebsiella pneumoniae harboring a New Delhi metallo-β-lactamase (NDM) plasmid in Ecuador and to present a map of reports of NDM isolates in South America. The modified Hodge test, carbapenem inactivation method, imipenem-EDTA disk method (synergy), and Rapidec Carba NP test were used to identify antibiotic resistance mechanisms. The presence of resistance genes was explored with a conjugation assay, and molecular confirmation of NDM was performed by PCR and DNA sequencing. Plasmid characterization was conducted by PCR-based replicon typing. A literature review was performed in Google Scholar and PubMed to identify reports from South America. An HIV-infected patient, who had never traveled abroad, developed a bloodstream infection caused by K. pneumoniae ST147 harboring the NDM-1 resistance gene in a plasmid from the IncA/C group. Local circulation of NDM has also been described in other South American countries, in particular in Colombia and Brazil, although published scientific records were not found for other countries. This report presents the first evidence of autochthonous circulation of the NDM-1 resistance gene harbored by an IncA/C plasmid isolated from a K. pneumoniae ST147 in Ecuador. Efforts should be implemented to monitor and characterize the spatial and temporal distribution of NDM in Ecuador and other countries of South America. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  4. U.S. response to a report of infectious salmon anemia virus in Western North America

    Science.gov (United States)

    Amos, Kevin H; Gustafson, Lori; Warg, Janet; Whaley, Janet; Purcell, Maureen K.; Rolland, Jill B.; Winton, James R.; Snekvik, Kevin; Meyers, Theodore; Stewart, Bruce; Kerwin, John; Blair, Marilyn; Bader, Joel; Evered, Joy

    2014-01-01

    Federal, state, and tribal fishery managers, as well as the general public and their elected representatives in the United States, were concerned when infectious salmon anemia virus (ISAV) was suspected for the first time in free-ranging Pacific Salmon collected from the coastal areas of British Columbia, Canada. This article documents how national and regional fishery managers and fish health specialists of the U.S. worked together and planned and implemented actions in response to the reported finding of ISAV in British Columbia. To date, the reports by Simon Fraser University remain unconfirmed and preliminary results from collaborative U.S. surveillance indicate that there is no evidence of ISAV in U.S. populations of free-ranging or marine-farmed salmonids on the west coast of North America.

  5. Microfossils in the Ordovician erratic boulders from South-western Finland

    Directory of Open Access Journals (Sweden)

    Nõlvak, J.

    1995-12-01

    Full Text Available Chitinozoans, ostracods and acritarchs found in four glacially transported limestone boulders from the south-western coast of Finland have been studied in order to test the usefulness of these microfossil groups in age determinations. Also rare specimens of conodonts, inarticulated brachiopods and foraminifers were found. Baltic limestone (or Östersjö limestone was the most problematic, because only fossils with calcitic or phosphatic shells are preserved. It is concluded that the boulders identified correlate with the Uhaku and Rakvere stages of the Middle Ordovician.

  6. Status and challenges for conservation of small mammal assemblages in South America.

    Science.gov (United States)

    Kelt, Douglas A; Meserve, Peter L

    2014-08-01

    South America spans about 44° latitude, covers almost 18 million km(2) , and is second only to Africa in continental mammal species richness. In spite of this richness, research on the status of this fauna and on the nature and magnitude of contemporary threats remains limited. Distilling threats to this diverse fauna at a continental scale is challenging, in part because of the limited availability of rigorous studies. Recognizing this constraint, we summarize key threats to small mammals in South America, emphasizing the roles of habitat loss and degradation, direct persecution, and the increasing threat of climate change. We focus on three regional 'case studies': the tropical Andes, Amazonia and adjacent lowland regions, and the southern temperate region. We close with a brief summary of recent findings at our long-term research site in north-central Chile as they pertain to projected threats to this fauna. Habitat alteration is a pervasive threat that has been magnified by market forces and globalization (e.g. extensive agricultural development in Amazonia), and threatens increasing numbers of populations and species. Climate change poses even greater threats, from changes in rainfall and runoff regimes and resulting changes in vegetative structure and composition to secondary influences on fire dynamics. It is likely that many changes have yet to be recognized, but existing threats suggest that the future may bring dramatic changes in the distribution of many mammal taxa, although it is not clear if key habitat elements (vegetation) will respond as rapidly as climatic factors, leading to substantial uncertainty. Climate change is likely to result in 'winners' and 'losers' but available information precludes detailed assessment of which species are likely to fall into which category. In the absence of long-term monitoring and applied research to characterize these threats more accurately, and to develop strategies to reduce their impacts, managers already are

  7. Total electron content responses to HILDCAAs and geomagnetic storms over South America

    Science.gov (United States)

    Mara de Siqueira Negreti, Patricia; Rodrigues de Paula, Eurico; Nicoli Candido, Claudia Maria

    2017-12-01

    Total electron content (TEC) is extensively used to monitor the ionospheric behavior under geomagnetically quiet and disturbed conditions. This subject is of greatest importance for space weather applications. Under disturbed conditions the two main sources of electric fields, which are responsible for changes in the plasma drifts and for current perturbations, are the short-lived prompt penetration electric fields (PPEFs) and the longer-lasting ionospheric disturbance dynamo (DD) electric fields. Both mechanisms modulate the TEC around the globe and the equatorial ionization anomaly (EIA) at low latitudes. In this work we computed vertical absolute TEC over the low latitude of South America. The analysis was performed considering HILDCAA (high-intensity, long-duration, continuous auroral electrojet (AE) activity) events and geomagnetic storms. The characteristics of storm-time TEC and HILDCAA-associated TEC will be presented and discussed. For both case studies presented in this work (March and August 2013) the HILDCAA event follows a geomagnetic storm, and then a global scenario of geomagnetic disturbances will be discussed. Solar wind parameters, geomagnetic indices, O / N2 ratios retrieved by GUVI instrument onboard the TIMED satellite and TEC observations will be analyzed and discussed. Data from the RBMC/IBGE (Brazil) and IGS GNSS networks were used to calculate TEC over South America. We show that a HILDCAA event may generate larger TEC differences compared to the TEC observed during the main phase of the precedent geomagnetic storm; thus, a HILDCAA event may be more effective for ionospheric response in comparison to moderate geomagnetic storms, considering the seasonal conditions. During the August HILDCAA event, TEC enhancements from ˜ 25 to 80 % (compared to quiet time) were observed. These enhancements are much higher than the quiet-time variability observed in the ionosphere. We show that ionosphere is quite sensitive to solar wind forcing and

  8. Disaster resilience assessment and the global agenda: A journey from India to South America

    Science.gov (United States)

    Fanchiotti, Margherita; Torres, Jair; Burton, Christopher; Makarigakis, Alexandros

    2016-04-01

    Governments and stakeholders worldwide are placing great emphasis on fostering the resilience of communities to natural hazards and disasters. This is partially because communities that can increase their resilience are in a better position to withstand the adverse effects of damaging hazard events when they occur. With disaster risk reduction having emerged as a global challenge, the Sendai Framework for Disaster Risk Reduction 2015-2030 has recognised the need to invest in enhancing disaster resilience as a priority on the international agenda. In order to successfully build community resilience to natural hazards, it then becomes essential to first understand, identify and assess all sets of conditions that contribute to resilience. The ability to measure resilience is increasingly being identified as a key step towards disaster risk reduction as a result. Relatively few studies, however, have been conducted to develop guidelines for measuring the concept, and more research is needed to develop effective tools for assessment of resilience in developing countries. This is because various environmental, built-environment, and social factors will operate and interact differentially across disaster and development contexts. This paper presents preliminary findings from two large projects in which the authors have been involved, namely the 'Enhancing Natural HAzards resilience iN South America' (ENHANS) and 'Deltas, Vulnerability & Climate Change: Migration & Adaptation' (DECCMA) projects. In collaboration with the Global Earthquake Model (GEM), the Understanding and Managing Extremes (UME) School of the Institute for Advanced Study (IUSS) of Pavia and the University of Southampton, UNESCO is working on the development of methods for disaster resilience measurement in developing nations. The studies build on the available literature to provide an ad-hoc conceptual framework for the quantification of community resilience in each study site by means of a bottom

  9. Total electron content responses to HILDCAAs and geomagnetic storms over South America

    Directory of Open Access Journals (Sweden)

    P. M. de Siqueira Negreti

    2017-12-01

    Full Text Available Total electron content (TEC is extensively used to monitor the ionospheric behavior under geomagnetically quiet and disturbed conditions. This subject is of greatest importance for space weather applications. Under disturbed conditions the two main sources of electric fields, which are responsible for changes in the plasma drifts and for current perturbations, are the short-lived prompt penetration electric fields (PPEFs and the longer-lasting ionospheric disturbance dynamo (DD electric fields. Both mechanisms modulate the TEC around the globe and the equatorial ionization anomaly (EIA at low latitudes. In this work we computed vertical absolute TEC over the low latitude of South America. The analysis was performed considering HILDCAA (high-intensity, long-duration, continuous auroral electrojet (AE activity events and geomagnetic storms. The characteristics of storm-time TEC and HILDCAA-associated TEC will be presented and discussed. For both case studies presented in this work (March and August 2013 the HILDCAA event follows a geomagnetic storm, and then a global scenario of geomagnetic disturbances will be discussed. Solar wind parameters, geomagnetic indices, O ∕ N2 ratios retrieved by GUVI instrument onboard the TIMED satellite and TEC observations will be analyzed and discussed. Data from the RBMC/IBGE (Brazil and IGS GNSS networks were used to calculate TEC over South America. We show that a HILDCAA event may generate larger TEC differences compared to the TEC observed during the main phase of the precedent geomagnetic storm; thus, a HILDCAA event may be more effective for ionospheric response in comparison to moderate geomagnetic storms, considering the seasonal conditions. During the August HILDCAA event, TEC enhancements from  ∼  25 to 80 % (compared to quiet time were observed. These enhancements are much higher than the quiet-time variability observed in the ionosphere. We show that ionosphere is quite sensitive to

  10. Detection of non-natural springtime precipitation change over northern South America

    Science.gov (United States)

    Barkhordarian, A.; Behrangi, A.; Mechoso, C. R.

    2017-12-01

    Here we determine whether the climate over South America has changed as a result of human activity since the beginning of the industrial revolution. To this end, we assess whether the observed changes are likely to have been due to natural (internal) variability alone, and if not, whether they are consistent with what models simulate as response to anthropogenic and natural forcing. Internal variability is estimated using 12,000-year control runs derived from CMIP5 archive. Results indicate that, in the past decades, trends in springtime (ASO, August-October) precipitation over South America have a magnitude that is beyond the estimated range due to natural (internal) variability or natural forcings alone. Evidence for the presence of an external driving factor is clearly detectable in the observed precipitation record (with less than 5% risk of error). The regression results illustrate the concerted emergence of an anthropogenic signal consistent with greenhouse gas (GHG) in observed decreasing 30-year trends of precipitation ending in 1998 and later on. In addition, the fingerprint of land-use-change signal is detectable in the observed precipitation decrease over 1983-2012. While the influence of GHG signal is detectable in precipitation, an observed decrease up to 10 mm/decade drying over the Amazon region, is much larger than the changes simulated by global and regional climate models as response to GHG forcing. We further show that the projected increasing trend of vapor pressure deficit (VPD), an indicator of background aridity, by the climate models with GHG forcing is much smaller than that observed over the Amazon rainforest. This may imply that models may underestimate the resulting reductions in forest CO2 uptake that could function as a positive feedback to rising temperature and reducing precipitation. Taking the ensemble of 23 IPCC models as a crude metric of probabilities, we further show that with 19 out of 24 models the effect of GS signal

  11. The extinction of Equidae and Proboscidea in South America. A test using Carbon isotope data

    Directory of Open Access Journals (Sweden)

    Prado, J. L.

    2011-12-01

    Full Text Available Carbon isotopes, preserved in 166 samples of fossil teeth and bone, provide key data for understanding the ecology of extinct horses and gomphotheres during the Plio-Pleistocene in South America. To analyze the patterns of dietary partitioning throughout this time we divided the samples into 19 groups, taking into account the genus and the age of the corresponding localities. In this study, the diets of both groups are assessed to test extinction hypotheses. The strong resource partitioning among herbivores assumed under Co-evolutionary disequilibrium hypothesis is supported by isotopic data of horses from latest Pleistocene. Hippidon and Equus had very different diets. In contrast, species of gomphotheres from late Pleistocene in South America seem to have had less specialized diets containing a broad mix of both C3 and C4 plants, which is in line with the dietary assumptions of the mosaic-nutrient hypothesis, but does not support the assumptions of Co-evolutionary disequilibrium hypothesis.

    Los isótopos del carbono preservados en 166 muestras de dientes y huesos fósiles son un dato clave para entender la ecología de los de caballos y gonfoterios durante el Plio-Pleistoceno en América del Sur. Para analizar los cambios en las reconstrucciones de la dieta durante este lapso temporal hemos dividido las muestras en 19 grupos, teniendo en cuenta la sistemática y la cronología de cada localidad. En este estudio, las dietas de ambos grupos son evaluadas para probar las hipótesis sobre su extinción. El alto fraccionamiento en el uso de los recursos entre los herbívoros que asume la hipótesis del desequilibrio co-evolutivo es sustentada por los datos isotópicos de los caballos del Pleistoceno tardío. Hippidion y Equus tenían una dieta muy diferente. En contraste, las especies de gonfoterios de finales del Pleistoceno parecen tener una dieta menos especializada con una combinación de

  12. Inorganic nitrogenous air pollutants, atmospheric nitrogen deposition and their potential ecological impacts in remote areas of western North America (Invited)

    Science.gov (United States)

    Bytnerowicz, A.; Fenn, M. E.; Fraczek, W.; Johnson, R.; Allen, E. B.

    2013-12-01

    , satellite-derived leaf area index and landscape cover. Ion exchange resin throughfall collectors and atmospheric simulation models have provided complementary data critical to better understanding of ecosystem responses to Nr in western North America. Such deposition data and maps have been used to set N deposition critical loads (CL) and to map areas of exceedance for a variety of ecosystem and biological effects. Empirical CL and exceedance areas have been established for many Western ecosystems including forest, desert, shrub, grassland, subalpine and aquatic habitats, thus providing an important management tool for protection of key ecosystems and the services they provide. An important finding is that biodiversity and community responses of sensitive elements of several Western aquatic and terrestrial ecosystems respond to relatively low levels of atmospheric N deposition (e.g., 3-6 kg N/ha/yr).

  13. Relative influence of human harvest, carnivores, and weather on adult female elk survival across western North America

    Science.gov (United States)

    Brodie, Jedediah; Johnson, Heather; Mitchell, Michael; Zager, Peter; Proffitt, Kelly; Hebblewhite, Mark; Kauffman, Matthew; Johnson, Bruce; Bissonette, John; Bishop, Chad; Gude, Justin; Herbert, Jeff; Hersey, Kent R.; Hurley, Mark; Lukacs, Paul M.; McCorquodale, Scott; McIntire, Eliot; Nowak, Josh; Sawyer, Hall; Smith, Douglas; White, P.J.

    2013-01-01

    Well-informed management of harvested species requires understanding how changing ecological conditions affect demography and population dynamics, information that is lacking for many species. We have limited understanding of the relative influence of carnivores, harvest, weather and forage availability on elk Cervus elaphus demography, despite the ecological and economic importance of this species. We assessed adult female survival, a key vital rate for population dynamics, from 2746 radio-collared elk in 45 populations across western North America that experience wide variation in carnivore assemblage, harvest, weather and habitat conditions. Proportional hazard analysis revealed that 'baseline' (i.e. not related to human factors) mortality was higher with very high winter precipitation, particularly in populations sympatric with wolves Canis lupus. Mortality may increase via nutritional stress and heightened vulnerability to predation in snowy winters. Baseline mortality was unrelated to puma Puma concolor presence, forest cover or summer forage productivity. Cause-specific mortality analyses showed that wolves and all carnivore species combined had additive effects on baseline elk mortality, but only reduced survival by <2%. When human factors were included, ‘total’ adult mortality was solely related to harvest; the influence of native carnivores was compensatory. Annual total mortality rates were lowest in populations sympatric with both pumas and wolves because managers reduced female harvest in areas with abundant or diverse carnivores. Mortality from native carnivores peaked in late winter and early spring, while harvest-induced mortality peaked in autumn. The strong peak in harvest-induced mortality during the autumn hunting season decreased as the number of native carnivore species increased. Synthesis and applications. Elevated baseline adult female elk mortality from wolves in years with high winter precipitation could affect elk abundance as

  14. Surface-air mercury fluxes across Western North America: A synthesis of spatial trends and controlling variables

    Energy Technology Data Exchange (ETDEWEB)

    Eckley, Chris S., E-mail: eckley.chris@epa.gov [US Environmental Protection Agency, Region-10, Seattle, WA 98101 (United States); Tate, Mike T. [US Geological Survey, Middleton, WI 53562 (United States); Lin, Che-Jen [Center for Advances on Water and Air quality, Lamar University, Beaumont, TX 77710 (United States); Gustin, Mae [Department of Natural Resources & Environmental Science, University of Nevada, Reno, NV 89557 (United States); Dent, Stephen [CDM Smith, Portland, OR 97205 (United States); Eagles-Smith, Collin [US Geological Survey, Corvallis, OR 97331 (United States); Lutz, Michelle A. [US Geological Survey, Middleton, WI 53562 (United States); Wickland, Kimberly P. [US Geological Survey Boulder, CO 80303 (United States); Wang, Bronwen [US Geological Survey, Anchorage, AK 99508 (United States); Gray, John E. [US Geological Survey, Denver, CO 80225 (United States); Edwards, Grant C. [Department of Environment and Geography, Macquarie University, North Ryde, NSW 2109 (Australia); Krabbenhoft, Dave P. [US Geological Survey, Middleton, WI 53562 (United States); Smith, David B. [US Geological Survey, Denver, CO 80225 (United States)

    2016-10-15

    Mercury (Hg) emission and deposition can occur to and from soils, and are an important component of the global atmospheric Hg budget. This paper focuses on synthesizing existing surface-air Hg flux data collected throughout the Western North American region and is part of a series of geographically focused Hg synthesis projects. A database of existing Hg flux data collected using the dynamic flux chamber (DFC) approach from almost a thousand locations was created for the Western North America region. Statistical analysis was performed on the data to identify the important variables controlling Hg fluxes and to allow spatiotemporal scaling. The results indicated that most of the variability in soil-air Hg fluxes could be explained by variations in soil-Hg concentrations, solar radiation, and soil moisture. This analysis also identified that variations in DFC methodological approaches were detectable among the field studies, with the chamber material and sampling flushing flow rate influencing the magnitude of calculated emissions. The spatiotemporal scaling of soil-air Hg fluxes identified that the largest emissions occurred from irrigated agricultural landscapes in California. Vegetation was shown to have a large impact on surface-air Hg fluxes due to both a reduction in solar radiation reaching the soil as well as from direct uptake of Hg in foliage. Despite high soil Hg emissions from some forested and other heavily vegetated regions, the net ecosystem flux (soil flux + vegetation uptake) was low. Conversely, sparsely vegetated regions showed larger net ecosystem emissions, which were similar in magnitude to atmospheric Hg deposition (except for the Mediterranean California region where soil emissions were higher). The net ecosystem flux results highlight the important role of landscape characteristics in effecting the balance between Hg sequestration and (re-)emission to the atmosphere. - Highlights: • Soil-air Hg fluxes are an important component of the

  15. Surface-air mercury fluxes across Western North America: A synthesis of spatial trends and controlling variables

    International Nuclear Information System (INIS)

    Eckley, Chris S.; Tate, Mike T.; Lin, Che-Jen; Gustin, Mae; Dent, Stephen; Eagles-Smith, Collin; Lutz, Michelle A.; Wickland, Kimberly P.; Wang, Bronwen; Gray, John E.; Edwards, Grant C.; Krabbenhoft, Dave P.; Smith, David B.

    2016-01-01

    Mercury (Hg) emission and deposition can occur to and from soils, and are an important component of the global atmospheric Hg budget. This paper focuses on synthesizing existing surface-air Hg flux data collected throughout the Western North American region and is part of a series of geographically focused Hg synthesis projects. A database of existing Hg flux data collected using the dynamic flux chamber (DFC) approach from almost a thousand locations was created for the Western North America region. Statistical analysis was performed on the data to identify the important variables controlling Hg fluxes and to allow spatiotemporal scaling. The results indicated that most of the variability in soil-air Hg fluxes could be explained by variations in soil-Hg concentrations, solar radiation, and soil moisture. This analysis also identified that variations in DFC methodological approaches were detectable among the field studies, with the chamber material and sampling flushing flow rate influencing the magnitude of calculated emissions. The spatiotemporal scaling of soil-air Hg fluxes identified that the largest emissions occurred from irrigated agricultural landscapes in California. Vegetation was shown to have a large impact on surface-air Hg fluxes due to both a reduction in solar radiation reaching the soil as well as from direct uptake of Hg in foliage. Despite high soil Hg emissions from some forested and other heavily vegetated regions, the net ecosystem flux (soil flux + vegetation uptake) was low. Conversely, sparsely vegetated regions showed larger net ecosystem emissions, which were similar in magnitude to atmospheric Hg deposition (except for the Mediterranean California region where soil emissions were higher). The net ecosystem flux results highlight the important role of landscape characteristics in effecting the balance between Hg sequestration and (re-)emission to the atmosphere. - Highlights: • Soil-air Hg fluxes are an important component of the

  16. Genetic conservation planning for forest tree species in Western North America under future climate change: Employing a novel approach to identify conservation gaps

    Science.gov (United States)

    L.K. Gray; E.J. Russell; Q.E. Barber; A. Hamann

    2017-01-01

    Among the 17 provinces, territories, and states that comprise western North America, approximately 18 percent of the 8.4 million km2 of forested land base is designated as protected areas to ensure the in situ conservation of forest biodiversity. Jurisdictions vary substantially however, in their responsibilities, protected area coverage, and conservation policies....

  17. Use of a constucted wetland to reduce nonpoint-source pesticide contamination of the Lourens River, South America

    Science.gov (United States)

    Ralf Schulz

    2000-01-01

    The Lourens River, Western Cape, South Africa, and its tributaries situated in an intensively cultivated orchard area receive pesticide contamination during rainfall-induced runoff and during spraydrift. A 0.44-ha constructed wetland, built in 1991 in one of the tributaries (summer flow 0.03 m3 per second), was studied in order to assess its effectiveness in reducing...

  18. Variations of Sea Surface Temperature, Wind Stress, and Rainfall over the Tropical Atlantic and South America.

    Science.gov (United States)

    Nobre, Paulo; Srukla, J.

    1996-10-01

    Empirical orthogonal functions (E0Fs) and composite analyses are used to investigate the development of sea surface temperature (SST) anomaly patterns over the tropical Atlantic. The evolution of large-scale rainfall anomaly patterns over the equatorial Atlantic and South America are also investigated. 71e EOF analyses revealed that a pattern of anomalous SST and wind stress asymmetric relative to the equator is the dominant mode of interannual and longer variability over the tropical Atlantic. The most important findings of this study are as follows.Atmospheric circulation anomalies precede the development of basinwide anomalous SST patterns over the tropical Atlantic. Anomalous SST originate off the African coast simultaneously with atmospheric circulation anomalies and expand westward afterward. The time lag between wind stress relaxation (strengthening) and maximum SST warming (cooling) is about two months.Anomalous atmospheric circulation patterns over northern tropical Atlantic are phase locked to the seasonal cycle. Composite fields of SLP and wind stress over northern tropical Atlantic can be distinguished from random only within a few months preceding the March-May (MAM) season. Observational evidence is presented to show that the El Niño-Southern Oscillation phenomenon in the Pacific influences atmospheric circulation and SST anomalies over northern tropical Atlantic through atmospheric teleconnection patterns into higher latitudes of the Northern Hemisphere.The well-known droughts over northeastern Brazil (Nordeste) are a local manifestation of a much larger-scale rainfall anomaly pattern encompassing the whole equatorial Atlantic and Amazon region. Negative rainfall anomalies to the south of the equator during MAM, which is the rainy season for the Nordeste region, are related to an early withdrawal of the intertropical convergence zone toward the warm SST anomalies over the northern tropical Atlantic. Also, it is shown that precipitation anomalies

  19. Effect of the lithospheric thermal state on the Moho interface: A case study in South America

    Science.gov (United States)

    Bagherbandi, Mohammad; Bai, Yongliang; Sjöberg, Lars E.; Tenzer, Robert; Abrehdary, Majid; Miranda, Silvia; Alcacer Sanchez, Juan M.

    2017-07-01

    Gravimetric methods applied for Moho recovery in areas with sparse and irregular distribution of seismic data often assume only a constant crustal density. Results of latest studies, however, indicate that corrections for crustal density heterogeneities could improve the gravimetric result, especially in regions with a complex geologic/tectonic structure. Moreover, the isostatic mass balance reflects also the density structure within the lithosphere. The gravimetric methods should therefore incorporate an additional correction for the lithospheric mantle as well as deeper mantle density heterogeneities. Following this principle, we solve the Vening Meinesz-Moritz (VMM) inverse problem of isostasy constrained by seismic data to determine the Moho depth of the South American tectonic plate including surrounding oceans, while taking into consideration the crustal and mantle density heterogeneities. Our numerical result confirms that contribution of sediments significantly modifies the estimation of the Moho geometry especially along the continental margins with large sediment deposits. To account for the mantle density heterogeneities we develop and apply a method in order to correct the Moho geometry for the contribution of the lithospheric thermal state (i.e., the lithospheric thermal-pressure correction). In addition, the misfit between the isostatic and seismic Moho models, attributed mainly to deep mantle density heterogeneities and other geophysical phenomena, is corrected for by applying the non-isostatic correction. The results reveal that the application of the lithospheric thermal-pressure correction improves the RMS fit of the VMM gravimetric Moho solution to the CRUST1.0 (improves ∼ 1.9 km) and GEMMA (∼1.1 km) models and the point-wise seismic data (∼0.7 km) in South America.

  20. The Archeomagnetic field in South America: Present status and perspectives (Invited)

    Science.gov (United States)

    Hartmann, G. A.; Trindade, R. I.; Gallet, Y.; Poletti, W.; Begnini, G. S.; Genevey, A.; Legoff, M.

    2013-12-01

    Geomagnetic field variations over decadal to millennial timescales can be determined from direct (i.e. observatory) and indirect (e.g. from archeological artifacts and volcanics) sources. Before the observatory era, the recovery of these variations is however still strongly penalized by the very uneven both geographical and temporal distributions of the available archeo/paleomagnetic dataset. In particular, the southern hemisphere contributes with only ~3% of the global archeomagnetic database. Moreover, most of these data present restrictions due to their poor experimental reliability and to the lack of good age control. Therefore, new intensity and directional data from the southern hemisphere are strongly requested for the next generation of archeomagnetic field models. In this presentation, we will report on intensity and inclination results obtained from different regions in Brazil. A collection of twenty-three site-mean archeointensity data were obtained by our team from architectural brick fragments dated to the past 500 years from Northeast and Southeast Brazil. This dataset was complemented by a series of new results from South Brazil. In addition, we also obtained inclination data, after reconstructing the firing position of the ancient bricks from modern analogs of historical brickyards. Thirteen site-mean inclination results dated to between 1790 AD and 1950 AD and five inclination results spanning the 1590-1920 AD time interval were so determined from Southeast and Northeast Brazil, respectively. Altogether, our data, which are geographically distributed over more than 20 degrees in latitude, allow us to discuss the large-scale influence in Brazil and South America of non-dipolar features of the geomagnetic field during the past few centuries.

  1. Discovery of an alien species of mayfly in South America (Ephemeroptera).

    Science.gov (United States)

    Salles, Frederico F; Gattolliat, Jean-Luc; Angeli, Kamila B; De-Souza, Márcia R; Gonçalves, Inês C; Nessimian, Jorge L; Sartori, Michel

    2014-01-01

    Despite its wide, almost worldwide distribution, the mayfly genus Cloeon Leach, 1815 (Ephemeroptera: Baetidae) is restricted in the Western hemisphere to North America, where a single species is reported. In the Neotropics, except for some species wrongly attributed to the genus in the past, there are no records of Cloeon. Recently, however, specimens of true Cloeon were collected along the coast of Espírito Santo, Southeastern Brazil. In order to verify the hypothesis that this species was recently introduced to Brazil, our aim was to identify the species based on morphological and molecular characters and to confirm the presence of true representatives of the genus in the Neotropics. Our results revealed that the specimens found in Brazil belong to the Afrotropical species C. smaeleni Lestage, 1924. The identity of the species, its distribution, along with its previous absence in regularly sampled sites, is a clear sign that the specimens of C. smaeleni found in Espírito Santo are introduced, well established, and that the colonization took place very recently.

  2. Insight conference reports : western Canada oil sands summit : meeting North America's energy needs

    International Nuclear Information System (INIS)

    2004-01-01

    This conference focused on exploration and development of oil sands in western Canada, with particular reference to market opportunities and challenges for oil sands exploitation in Alberta, risk management in large resource development projects, pipeline issues, investment issues, and asset life cycle management. Some presentations also addressed regulatory regimes, royalty regimes, taxes, resource potential, research activities, environmental impacts, and offshore prospects. Both industry and government have an interest in ensuring resources are developed in a sustainable manner. The influence of the Kyoto Protocol on oil sands development and the greenhouse gas emissions market was also addressed along with joint venture issues and a comparison of extra-heavy crude oil projects in Venezuela and Canada. The conference featured 20 presentations, of which 8 have been indexed separately for inclusion in this database. refs., tabs., figs

  3. First record of Annonaceae wood for the Neogene of South America, Amazon Basin, Brazil

    Directory of Open Access Journals (Sweden)

    Emilio Alberto Amaral Soares

    Full Text Available ABSTRACT: The relief of the regions of Manaus and Itacoatiara, Central Amazon, is supported by Neogene siliciclastic rocks, bounded at the base and top by lateritic paleosols and covered by quaternary sedimentary deposits from the Solimões-Amazon river system. This unit is informally assigned to the Novo Remanso Formation, consists of usually reddish and ferruginized sandstones, conglomerates and pelites, with few identified fossil records, a fact that has hindered its stratigraphic position, and the paleoenvironmental reconstruction of the last phase of the Amazon Basin settling. This study describes, for the first time, the occurrence of fossil wood in outcroppings of the left bank of the Amazon River, where anatomical and morphological data has enabled its characterization to the species level. Thus, the data marks the record of the Annonaceae in South America, as well as the depositional processes related to incorporation of organic material in the sandy layer and the fossilization processes that allowed its preservation. In an unprecedented way, this study has described Duguetiaxylon amazonicum nov. gen and sp. and provided information on the anatomical and systematic character, as well as data on plant-insect interaction, and a better understanding of the family.

  4. Solar ultraviolet radiation: properties, characteristics and amounts observed in Brazil and South America.

    Science.gov (United States)

    Corrêa, Marcelo de Paula

    2015-01-01

    The beneficial and harmful effects of human exposure to solar ultraviolet radiation (UV-R) are topics that arouse great interest not only among physicians and scientists, but also the general public and the media. Currently, discussions on vitamin D synthesis (beneficial effect) are confronted with the high and growing number of new cases of non-melanoma skin cancer and other diseases of the skin and eyes (harmful effect) diagnosed each year in Brazil. However, the lack of scientific knowledge on the UV-R in Brazil and South America leads to adoption of protective measures based on studies conducted in Europe and USA, where the amounts of UV-R available at surface and the sun-exposure habits and characteristics of the population are significantly different from those observed in Brazil. In order to circumvent this problem, the Brazilian Society of Dermatology recently published the Brazilian Consensus of Photoprotection based on recent studies performed locally. The main goal of this article is to provide detailed educational information on the main properties and characteristics of UV-R and UV index in a simple language. It also provides: a) a summary of UV-R measurements recently performed in Brazil; b) a comparison with those performed in Europe; and, c) an evaluation to further clarify the assessment of potential harm and health effects owing to chronic exposures.

  5. Report on the results of the ninth medical examination of atomic bomb survivors in South America

    International Nuclear Information System (INIS)

    Ohta, Michiya; Hiyama, Keiko; Matsuo, Kakaru; Yamamoto, Hiroki; Nishida, Masashi; Sasaki, Yoshinobu

    2001-01-01

    The results of the ninth medical examination are reported. Atomic bomb survivors who had emigrated to South America as of November 2000 totaled 180 (153 to Brazil, 4 to Paraguay, 7 to Bolivia, 13 to Argentina, and 3 to Peru). Eighty persons (44.4%) were examined (62 in Brazil, 2 in Paraguay, 6 in Bolivia, 7 in Argentina, and 3 in Peru). The mean age of the males was 71.3 years, and the mean age of the females was 69.7 years. They had hypertension (24.1%), diabetes (10.1%), cancer (8.9%), heart disease (7.6%), and thyroid disease (2.5%). The most common manifestations of illness were fatigue (69.6%), loss of vigor (65.8%), taking medicine (55.7%), and heat intolerance (53.2%). The incident rates of electrocardiographic abnormalities and urine, blood, and biochemical tests abnormalities were almost the same as at the previous examination, and there was no change in the percentage of those who required detailed tests and treatment. When independence in daily life was judged by the criteria of the nursing care insurance system, 68 persons were judged ''independent'', and 7 persons ''handicapped.'' (K.H.)

  6. Report on the results of the ninth medical examination of atomic bomb survivors in South America

    Energy Technology Data Exchange (ETDEWEB)

    Ohta, Michiya [Hiroshima Atomic Bomb Hospital (Japan); Hiyama, Keiko; Matsuo, Kakaru; Yamamoto, Hiroki; Nishida, Masashi; Sasaki, Yoshinobu

    2001-06-01

    The results of the ninth medical examination are reported. Atomic bomb survivors who had emigrated to South America as of November 2000 totaled 180 (153 to Brazil, 4 to Paraguay, 7 to Bolivia, 13 to Argentina, and 3 to Peru). Eighty persons (44.4%) were examined (62 in Brazil, 2 in Paraguay, 6 in Bolivia, 7 in Argentina, and 3 in Peru). The mean age of the males was 71.3 years, and the mean age of the females was 69.7 years. They had hypertension (24.1%), diabetes (10.1%), cancer (8.9%), heart disease (7.6%), and thyroid disease (2.5%). The most common manifestations of illness were fatigue (69.6%), loss of vigor (65.8%), taking medicine (55.7%), and heat intolerance (53.2%). The incident rates of electrocardiographic abnormalities and urine, blood, and biochemical tests abnormalities were almost the same as at the previous examination, and there was no change in the percentage of those who required detailed tests and treatment. When independence in daily life was judged by the criteria of the nursing care insurance system, 68 persons were judged ''independent'', and 7 persons ''handicapped.'' (K.H.)

  7. Mercury in environmental samples from a waterbody contaminated by gold mining in Colombia, South America.

    Science.gov (United States)

    Olivero, J; Solano, B

    1998-06-30

    Environmental samples from a marsh, which receives mercury discharges from a gold mine in Colombia (South America), were evaluated for total mercury content. Mercury concentrations were analyzed in sediments, macrophytes and fish species from different trophic levels. The Mean mercury levels in sediments oscillated between 140 and 355 micrograms/kg whereas in the macrophyte Eichornia crassipes levels were between 219 and 277 microgram/kg with practically no interseasonal variations. The mercury content in the muscle of fish varied depending on the position in the trophic chain and the feeding habits of each species, oscillating between non-detectable (< 7.4 microgram/kg) and 1084 micrograms/kg. Seasonal variations were only observed in fish species whose habitats are mostly the bottom sediment. The presence of mercury in some fish appeared to be the result of bioaccumulation rather than a biomagnification processes. This was clearly evidenced in the detritivorous species Triportheus magdalenae which obtain their food within the sediments and whose mercury concentrations were significantly higher when compared to the other species including carnivorous. The relatively low mercury concentrations found in fish may be due to both the dispersion of the contaminant once it reaches the waterbody and the migrational characteristics of the fish species.

  8. Monitoring strategy for eight amphibian species in French Guiana, South America.

    Directory of Open Access Journals (Sweden)

    Elodie A Courtois

    Full Text Available Although dramatic amphibian declines have been documented worldwide, only few of such events have been quantitatively documented for the tropical forests of South America. This is due partly to the fact that tropical amphibians are patchily distributed and difficult to detect. We tested three methods often used to monitor population trends in amphibian species in a remote lowland tropical forest of French Guiana. These methods are capture-mark-recapture (CMR, estimation of the number of calling males with repeated counts data and distance sampling, and rates of occupancy inferred by presence/absence data. We monitored eight diurnal, terrestrial amphibian species including five Dendrobatidae and three Bufonidae. We found that CMR, the most precise way of estimating population size, can be used only with two species in high density patches where the recapture rate is high enough. Only for one of the species (Dendrobates tinctorius, a low coefficient of variation (CV = 0.19 can be achieved with 15 to 20 capture events. For dendrobatid species with day-calling males, audio surveys yield a better probability of detection with only 8 audio surveys needed; quantitative estimates can be achieved by computing the number of calling males inferred from audio counts or distance sampling analysis. We therefore suggest that an efficient monitoring protocol for Neotropical amphibian species should include a combination of sighting and audio techniques, and we discuss the need of implementing a large-scale monitoring in order to provide a baseline for comparison with future changes.

  9. Sustainable management of the Gran Chaco of South America: Ecological promise and economic constraints

    Energy Technology Data Exchange (ETDEWEB)

    Bucher, E.H.; Huszar, P.C.

    1999-10-01

    The vast plain known as the Gran Chaco is a natural region of more than 1--3 million square kilometers, the second largest natural biome in south America, with only the Amazon region being larger. It extends over parts of Argentina, Bolivia, Paraguay and, marginally, Brazil. The original landscape of the region was mostly a park land with patches of hardwoods intermingled with grasslands. Increasing human encroachment, largely by poor campesinos, with associated overgrazing, excessive timber harvesting, charcoal production and over-exploitation of wildlife, is transforming the region into a dense and unproductive shrub land and is contributing to increasing rural poverty. A management system for the sustainable use of the Chaco has been developed based on a multiple-species ranching system that includes beef, timber, charcoal and wildlife production. An evaluation of the management system finds that it is capable of protecting and enhancing the resource base, while providing higher economic returns in a sustainable manner. However, high initial costs, as well as a divergence between the best interests of campersinos and society, jeopardize the feasibility of the managed system.

  10. Care of patients with Huntington's disease in South America: a survey

    Directory of Open Access Journals (Sweden)

    Ricardo Oliveira Horta Maciel

    2013-06-01

    Full Text Available Huntington's disease (HD is a rare neurodegenerative disease with a multitude of symptoms, which requires access to specialized multidisciplinary care for adequate management. The aim of this study was to survey the characteristics of care in various HD centers in South America (SA. Methods A questionnaire was sent to 24 centers involved in the care for HD patients in SA. Results Of the total 24 centers, 19 (79.2% are academic units. The majority of centers (62.5% are general movement disorders clinics. Multidisciplinary care is available in 19 (79.2% centers and in 20 (83.3% care is provided free of charge. Genetic testing and counseling are available in 25 and 66.6% of centers, respectively. The majority of centers (83.3% have no institutional support for end-stage care. Conclusions Although HD centers in SA are committed to providing multidisciplinary care, access to genetic counseling and end-stage care are lacking in most centers.

  11. Moho map of South America from receiver functions and surface waves

    Science.gov (United States)

    Lloyd, Simon; van der Lee, Suzan; FrançA, George Sand; AssumpçãO, Marcelo; Feng, Mei

    2010-11-01

    We estimate crustal structure and thickness of South America north of roughly 40°S. To this end, we analyzed receiver functions from 20 relatively new temporary broadband seismic stations deployed across eastern Brazil. In the analysis we include teleseismic and some regional events, particularly for stations that recorded few suitable earthquakes. We first estimate crustal thickness and average Poisson's ratio using two different stacking methods. We then combine the new crustal constraints with results from previous receiver function studies. To interpolate the crustal thickness between the station locations, we jointly invert these Moho point constraints, Rayleigh wave group velocities, and regional S and Rayleigh waveforms for a continuous map of Moho depth. The new tomographic Moho map suggests that Moho depth and Moho relief vary slightly with age within the Precambrian crust. Whether or not a positive correlation between crustal thickness and geologic age is derived from the pre-interpolation point constraints depends strongly on the selected subset of receiver functions. This implies that using only pre-interpolation point constraints (receiver functions) inadequately samples the spatial variation in geologic age. The new Moho map also reveals an anomalously deep Moho beneath the oldest core of the Amazonian Craton.

  12. Southern promises: a snapshot of the microbiology research landscape in South America based on bibliometric data.

    Science.gov (United States)

    Nai, Corrado

    2017-09-01

    Scientists have a single currency for productivity and impact: published articles. In an effort to map the global research landscape in microbiology, and to obviate the current lack of bibliometric analysis in the field, FEMS-the Federation of European Microbiological Societies-generated a dataset encompassing an exhaustive, worldwide list of microbiology studies for 2013-14, which further includes information as author affiliation, funding agency and number of citations. The manually curated database is useful in assessing the impact and regional productivity of microbiology research at different levels. Here, the data for microbiology research in South America are presented and discussed in detail. Based on the analysis, it emerged that despite great degrees of variation between number of published articles among the countries, a more levelled research productivity was observed when considering further dimensions like population size or number of research institutes. Normalised productivity and impact increase in countries with a 'central research hub', i.e. an institute or university producing a substantial portion of the national output (15% or more). From these observations, a possible strategy to increase impact and productivity in (microbiology) research for emerging countries is outlined. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. A scenario elicitation methodology to identify the drivers of electricity infrastructure cost in South America

    Science.gov (United States)

    Moksnes, Nandi; Taliotis, Constantinos; Broad, Oliver; de Moura, Gustavo; Howells, Mark

    2017-04-01

    Developing a set of scenarios to assess a proposed policy or future development pathways requires a certain level of information, as well as establishing the socio-economic context. As the future is difficult to predict, great care in defining the selected scenarios is needed. Even so it can be difficult to assess if the selected scenario is covering the possible solution space. Instead, this paper's methodology develops a large set of scenarios (324) in OSeMOSYS using the SAMBA 2.0 (South America Model Base) model to assess long-term electricity supply scenarios and applies a scenario-discovery statistical data mining algorithm, Patient Rule Induction Method (PRIM). By creating a multidimensional space, regions related to high and low cost can be identified as well as their key driver. The six key drivers are defined a priori in three (high, medium, low) or two levers (high, low): 1) Demand projected from GDP, population, urbanization and transport, 2) Fossil fuel price, 3) Climate change impact on hydropower, 4) Renewable technology learning rate, 5) Discount rate, 6) CO2 emission targets.

  14. Solar ultraviolet radiation: properties, characteristics and amounts observed in Brazil and South America*

    Science.gov (United States)

    Corrêa, Marcelo de Paula

    2015-01-01

    The beneficial and harmful effects of human exposure to solar ultraviolet radiation (UV-R) are topics that arouse great interest not only among physicians and scientists, but also the general public and the media. Currently, discussions on vitamin D synthesis (beneficial effect) are confronted with the high and growing number of new cases of non-melanoma skin cancer and other diseases of the skin and eyes (harmful effect) diagnosed each year in Brazil. However, the lack of scientific knowledge on the UV-R in Brazil and South America leads to adoption of protective measures based on studies conducted in Europe and USA, where the amounts of UV-R available at surface and the sun-exposure habits and characteristics of the population are significantly different from those observed in Brazil. In order to circumvent this problem, the Brazilian Society of Dermatology recently published the Brazilian Consensus of Photoprotection based on recent studies performed locally. The main goal of this article is to provide detailed educational information on the main properties and characteristics of UV-R and UV index in a simple language. It also provides: a) a summary of UV-R measurements recently performed in Brazil; b) a comparison with those performed in Europe; and, c) an evaluation to further clarify the assessment of potential harm and health effects owing to chronic exposures. PMID:26131858

  15. Investigations on mechanical biological treatment of waste in South America: Towards more sustainable MSW management strategies

    International Nuclear Information System (INIS)

    Bezama, Alberto; Aguayo, Pablo; Konrad, Odorico; Navia, Rodrigo; Lorber, Karl E.

    2007-01-01

    This work presents an analysis on the suitability of mechanical biological treatment of municipal solid waste in South America, based on two previous experimental investigations carried out in two different countries. The first experiment was performed for determining the mass and volume reduction of MSW in the province of Concepcion (Chile). The implemented bench-scale process consisted of a manual classification and separation stage, followed by an in-vessel biological degradation process. The second experiment consisted of a full-scale experiment performed in the city of Estrela (Brazil), where the existing municipal waste management facility was adapted to enhance the materials sorting and separation. Expressed in wet weight composition, 85.5% of the material input in the first experiment was separated for biological degradation. After 27 days of processing, 60% of the initial mass was reduced through degradation and water evaporation. The final fraction destined for landfilling equals 59% of the total input mass, corresponding to about 50% of the initial volume. In the second experiment, the fraction destined to landfill reaches 46.6% of the total input waste mass, whilst also significantly reducing the total volume to be disposed. These results, and the possible recovery of material streams suitable for recycling or for preparing solid recovered fuels, are the main advantages of the studied process

  16. Projected precipitation changes in South America: a dynamical downscaling within CLARIS

    Energy Technology Data Exchange (ETDEWEB)

    Soerensson, Anna A. [Centra de Investigaciones del Mar y la Atmosfera, CONICET/UBA, Buenos Aires (Argentina); Menendez, Claudio G. [Centra de Investigaciones del Mar y la Atmosfera, CONICET/UBA, Buenos Aires (Argentina); Dept. de Ciencias de la Atmosfera y los Oceanos, FCEN, UBA, Buenos Aires (Argentina); Ruscica, Romina; Alexander, Peter [Dept. de Fisica, FCEN, UBA, Buenos Aires (Argentina); Samuelsson, Patrick; Willen, Ulrika [Rossby Centre, SMHI, Norrkoeping (Sweden)

    2010-06-15

    Responses of precipitation seasonal means and extremes over South America in a downscaling of a climate change scenario are assessed with the Rossby Centre Regional Atmospheric Model (RCA). The anthropogenic warming under A1B scenario influences more on the likelihood of occurrence of severe extreme events like heavy precipitation and dry spells than on the mean seasonal precipitation. The risk of extreme precipitation increases in the La Plata Basin with a factor of 1.5-2.5 during all seasons and in the northwestern part of the continent with a factor 1.5-3 in summer, while it decreases in central and northeastern Brazil during winter and spring. The maximum amount of 5-days precipitation increases by up to 50% in La Plata Basin, indicating risks of flooding. Over central Brazil and the Bolivian lowland, where present 5-days precipitation is higher, the increases are similar in magnitude and could cause less impacts. In southern Amazonia, northeastern Brazil and the Amazon basin, the maximum number of consecutive dry days increases and mean winter and spring precipitation decreases, indicating a longer dry season. In the La Plata Basin, there is no clear pattern of change for the dry spell duration. (orig.)

  17. Implications of differences in bioanalytical regulations between Canada, USA and South America.

    Science.gov (United States)

    Arnold, Mark E

    2011-02-01

    To complete globally, pharmaceutical companies desire to use bioanalytical data and reports as a single version for all filings; not revising for specific countries or regions. Historically, this meant following the US FDA and International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use guidance/guidelines; finding them sufficient to achieve global acceptance. However, a growing challenge of the past decade has been additional country-specific and regional regulations that have been released. The differences between the bioanalytical regulations among countries have been recognized as a challenge to the pharmaceutical industry and its CRO partners. Harmonization of the regulations at a global level has been the subject of a number of recent articles and editorials, and the topic has been vigorously discussed at several conferences over the past year. Since all have been in agreement about the need to harmonize regulations, this article will not focus on harmonization but rather it will provide a comparison of the USA/Canadian regulations versus those of South America, in particular Brazil, noting the additional work needed to achieve compliance with country-specific regulations. All countries discussed have specific guidance or regulations on clinical bioequivalence studies, and due to the higher standards for these studies, the regulations for bioequivalence studies will be used as the basis for comparison in the article.

  18. El Dorado : Peru is trying to catch Colombia as the must go jurisdiction in South America

    International Nuclear Information System (INIS)

    Stastny, R.P.

    2010-01-01

    Peru has vast and largely untapped reserves of crude and natural gas, but it wants foreign help to increase oil production to 500,000 barrels per day in 4 years from the current level of 140,000 barrels per day. Perupetro is a state company in Peru responsible for promoting investment in the petroleum sector. Peru hopes to lure nearly $2 billion in oil investment to its northern Amazon region through 2013. Companies operating in South America have been attracted to Peru in recent years by its exploration potential and one of the best fiscal regimes in the world, at a 5 percent minimum royalty and a 20 percent maximum royalty. However, the government has changed the rules for the blocks offered in the 2010 bid process, increasing the minimum royalty to 15 percent and the maximum to 35 percent. The intent was to bring the higher royalties more in line with Colombia's. However, some analysts claim that Peru lacks the critical mass to justify the increase in royalties. Other challenges facing resource development in Peru include lack of infrastructure and a slow regulatory system. Twenty-five blocks of land are up for bid in 2010, mostly early stage properties. The bidding process will indicate how companies will respond to the new economics of these blocks. 1 tab.

  19. Last Glacial mammals in South America: a new scenario from the Tarija Basin (Bolivia)

    Science.gov (United States)

    Coltorti, M.; Abbazzi, L.; Ferretti, M. P.; Iacumin, P.; Rios, F. Paredes; Pellegrini, M.; Pieruccini, P.; Rustioni, M.; Tito, G.; Rook, L.

    2007-04-01

    The chronology, sedimentary history, and paleoecology of the Tarija Basin (Bolivia), one of the richest Pleistocene mammalian sites in South America, are revised here based on a multidisciplinary study, including stratigraphy, sedimentology, geomorphology, paleontology, isotope geochemistry, and 14C geochronology. Previous studies have indicated a Middle Pleistocene age for this classic locality. We have been able to obtain a series of 14C dates encompassing all the fossil-bearing sequences previously studied in the Tarija Basin. The dated layers range in age from about 44,000 to 21,000 radiocarbon years before present (BP), indicating that the Tarija fauna is much younger than previously thought. Glacial advances correlated to marine isotopic stages (MIS) 4 and 2 (ca. 62 and 20 ka BP, respectively) are also documented at the base and at the very top of the Tarija Padcaya succession, respectively, indicating that the Bolivian Altiplano was not dry but sustained an ice cap during the Last Glacial Maximum. The results of this multidisciplinary study enable us to redefine the chronological limits of the Tarija sequence and of its faunal assemblage and to shift this paleontological, paleoclimatological, and paleoecological framework to the time interval from MIS 4 to MIS 2.

  20. Ecology, livelihoods, and management of the Mauritia flexuosa palm in South America

    Directory of Open Access Journals (Sweden)

    Arika Virapongse

    2017-04-01

    Full Text Available Mauritia flexuosa is a key ecological and economic palm found throughout tropical South America. To inform improved management of M. flexuosa, we conducted a systematic review of published information about the ecology, livelihoods, and management of M. flexuosa, synthesized the information and identified knowledge gaps, and analyzed the spatial distribution of publications. A total of 143 documents (primary research, literature reviews, and grey literature were reviewed. Most published information originates from Peru and Brazil, with a disproportionate number of documents based in the Loreto Department of Peru. Significant geographical gaps in published information exist, especially in the northern portion of the species range. Existing literature emphasizes M. flexuosa fruit, although leaves, oil, and other products play important roles economically. To improve M. flexuosa management, we recommend that future research focuses on: (1 M. flexuosa availability; (2 harvest and cultivation; (3 development of consistent methods and standards; (4 landscape-level issues like land use change; (5 M. flexuosa within broader systems; (6 spatial gaps in research; (7 long-term research; and (8 multi- and interdisciplinary approaches.

  1. Southern Annular Mode drives multicentury wildfire activity in southern South America.

    Science.gov (United States)

    Holz, Andrés; Paritsis, Juan; Mundo, Ignacio A; Veblen, Thomas T; Kitzberger, Thomas; Williamson, Grant J; Aráoz, Ezequiel; Bustos-Schindler, Carlos; González, Mauro E; Grau, H Ricardo; Quezada, Juan M

    2017-09-05

    The Southern Annular Mode (SAM) is the main driver of climate variability at mid to high latitudes in the Southern Hemisphere, affecting wildfire activity, which in turn pollutes the air and contributes to human health problems and mortality, and potentially provides strong feedback to the climate system through emissions and land cover changes. Here we report the largest Southern Hemisphere network of annually resolved tree ring fire histories, consisting of 1,767 fire-scarred trees from 97 sites (from 22 °S to 54 °S) in southern South America (SAS), to quantify the coupling of SAM and regional wildfire variability using recently created multicentury proxy indices of SAM for the years 1531-2010 AD. We show that at interannual time scales, as well as at multidecadal time scales across 37-54 °S, latitudinal gradient elevated wildfire activity is synchronous with positive phases of the SAM over the years 1665-1995. Positive phases of the SAM are associated primarily with warm conditions in these biomass-rich forests, in which widespread fire activity depends on fuel desiccation. Climate modeling studies indicate that greenhouse gases will force SAM into its positive phase even if stratospheric ozone returns to normal levels, so that climate conditions conducive to widespread fire activity in SAS will continue throughout the 21st century.

  2. Uranium-series disequilibrium studies in phosphorite nodules from the west coast of South America

    International Nuclear Information System (INIS)

    Burnett, W.C.; Veeh, H.H.

    1977-01-01

    Sedimentary phosphorites occurring on the sea floor off Peru and Chile have been analyzed for U and Th isotopes, to establish their ages and hence obtain clues for their mode of formation. Fission-track distribution studies indicate that the U is primarily associated with the apatite fraction. Uranium-series disequilibrium methods, therefore, should be applicable, if the U incorporation is syngenetic with the apatite. The fractionation of U isotopes between oxidation states in the relatively young phosphorites from South America is low compared to that in older deposits. This supports the contention of Kolodny et al., (Geochim.Cosmochim.Acta;34:3 (1970)) that the major mechanism of 234 U/ 238 U fractionation is displacement of 234 U atoms into sites where they are more 'oxidizable' than the 238 U parent. Age estimates based on 234 U(IV) and 230 Th contents are internally consistent and range from late Pleistocene to Recent. The results indicate that marine phosphorites are currently forming in this area of intense oceanic upwelling. The age pattern during the last 150,000 yr suggests a correlation with eustatic high sea level stands and implies that conditions were more favourable for apatite genesis in this area during interglacials rather than during glacial times. (author)

  3. Spatial and temporal uplift history of South America from calibrated drainage analysis

    Science.gov (United States)

    Rodríguez Tribaldos, V.; White, N. J.; Roberts, G. G.; Hoggard, M. J.

    2017-06-01

    A multidisciplinary approach is used to analyze the Cenozoic uplift history of South America. Residual depth anomalies of oceanic crust abutting this continent help to determine the pattern of present-day dynamic topography. Admittance analysis and crustal thickness measurements indicate that the elastic thickness of the Borborema and Altiplano regions is ≤10 km with evidence for sub-plate support at longer wavelengths. A drainage inventory of 1827 river profiles is assembled and used to investigate landscape development. Linear inverse modeling enables river profiles to be fitted as a function of the spatial and temporal history of regional uplift. Erosional parameters are calibrated using observations from the Borborema Plateau and tested against continent-wide stratigraphic and thermochronologic constraints. Our results predict that two phases of regional uplift of the Altiplano plateau occurred in Neogene times. Regional uplift of the southern Patagonian Andes also appears to have occurred in Early Miocene times. The consistency between observed and predicted histories for the Borborema, Altiplano, and Patagonian plateaux implies that drainage networks record coherent signals that are amenable to simple modeling strategies. Finally, the predicted pattern of incision across the Amazon catchment constrains solid sedimentary flux at the Foz do Amazonas. Observed and calculated flux estimates match, suggesting that erosion and deposition were triggered by regional Andean uplift during Miocene times.

  4. Cryptococcus gattii: Emergence in Western North America: Exploitation of a Novel Ecological Niche

    Directory of Open Access Journals (Sweden)

    Kausik Datta

    2009-01-01

    Full Text Available The relatively uncommon fungal pathogen Cryptococcus gattii recently emerged as a significant cause of cryptococcal disease in human and animals in the Pacific Northwest of North America. Although genetic studies indicated its possible presence in the Pacific Northwest for more than 30 years, C. gattii as an etiological agent was largely unknown in this region prior to 1999. The recent emergence may have been encouraged by changing conditions of climate or land use and/or host susceptibility, and predictive ecological niche modeling indicates a potentially wider spread. C. gattii can survive wide climatic variations and colonize the environment in tropical, subtropical, temperate, and dry climates. Long-term climate changes, such as the significantly elevated global temperature in the last 100 years, influence patterns of disease among plants and animals and create niche microclimates habitable by emerging pathogens. C. gattii may have exploited such a hitherto unrecognized but clement environment in the Pacific Northwest to provide a wider exposure and risk of infection to human and animal populations.

  5. Evolution and trends of the dietetics profession in the United States of America and in Argentina: north and south united by similar challenges.

    Science.gov (United States)

    Defranchi, Romina L Barritta de; Nelson, Jennifer K

    2009-06-01

    Since the early stages the profession of dietetics has been characterized as a multifaceted discipline and influenced by scientific and social changes. Today, health and nutrition-related diseases are becoming more global--as is the dietetics profession. The aim of this article is to review the history, education, work and challenges for dietetic practitioners in North and South America, specifically in the United States and in the Argentinean Republic. It was in Argentina where the first Latin American dietetics school was established. Both countries have since shaped the profession creating standards for education and practice in response to advances in the biopsychosocial sciences and economic and environmental changes. Reviewing both the past and current diversities in both Americas contributes to a better understanding of professional strengths and weaknesses, and can prepare dietetics specialists to meet today's needs. Regardless of local disparities, it is interesting that current and future challenges for the dietetics profession are similar between the two countries, such as growing rates of obesity, limited access to and choice of healthy diets among various income groups, busy lifestyles and decline of family meals. These common issues and the availability of Internet tools offer a unique opportunity for partnership and research that can lead to successful creative nutrition interventions and programs. In turn, such joint initiatives will confirm the essential role for the profession--not only in the western hemisphere--but also globally.

  6. Long-Term Seasonal and Interannual Patterns of Marine Mammal Strandings in Subtropical Western South Atlantic

    Science.gov (United States)

    Prado, Jonatas H. F.; Mattos, Paulo H.; Silva, Kleber G.; Secchi, Eduardo R.

    2016-01-01

    Understanding temporal patterns of marine mammal occurrence is useful for establishing conservation strategies. We used a 38 yr-long dataset spanning 1976 to 2013 to describe temporal patterns and trends in marine mammal strandings along a subtropical stretch of the east coast of South America. This region is influenced by a transitional zone between tropical and temperate waters and is considered an important fishing ground off Brazil. Generalized Additive Models were used to evaluate the temporal stranding patterns of the most frequently stranded species. Forty species were documented in 12,540 stranding events. Franciscana (n = 4,574), South American fur seal, (n = 3,419), South American sea lion (n = 2,049), bottlenose dolphins (n = 293) and subantarctic fur seal (n = 219) were the most frequently stranded marine mammals. The seasonality of strandings of franciscana and bottlenose dolphin coincided with periods of higher fishing effort and strandings of South American and subantarctic fur seals with post-reproductive dispersal. For South American sea lion the seasonality of strandings is associated with both fishing effort and post-reproductive dispersal. Some clear seasonal patterns were associated with occurrence of cold- (e.g. subantarctic fur seal) and warm-water (e.g. rough-toothed dolphin) species in winter and summer, respectively. Inter-annual increases in stranding rate were observed for franciscana and South American fur seal and these are likely related to increased fishing effort and population growth, respectively. For subantarctic fur seal the stranding rate showed a slight decline while for bottlenose dolphin it remained steady. No significant year to year variation in stranding rate was observed for South American sea lion. The slight decrease in frequency of temperate/polar marine mammals and the increased occurrence of subtropical/tropical species since the late 1990s might be associated with environmental changes linked to climate change

  7. Long-Term Seasonal and Interannual Patterns of Marine Mammal Strandings in Subtropical Western South Atlantic.

    Directory of Open Access Journals (Sweden)

    Jonatas H F Prado

    Full Text Available Understanding temporal patterns of marine mammal occurrence is useful for establishing conservation strategies. We used a 38 yr-long dataset spanning 1976 to 2013 to describe temporal patterns and trends in marine mammal strandings along a subtropical stretch of the east coast of South America. This region is influenced by a transitional zone between tropical and temperate waters and is considered an important fishing ground off Brazil. Generalized Additive Models were used to evaluate the temporal stranding patterns of the most frequently stranded species. Forty species were documented in 12,540 stranding events. Franciscana (n = 4,574, South American fur seal, (n = 3,419, South American sea lion (n = 2,049, bottlenose dolphins (n = 293 and subantarctic fur seal (n = 219 were the most frequently stranded marine mammals. The seasonality of strandings of franciscana and bottlenose dolphin coincided with periods of higher fishing effort and strandings of South American and subantarctic fur seals with post-reproductive dispersal. For South American sea lion the seasonality of strandings is associated with both fishing effort and post-reproductive dispersal. Some clear seasonal patterns were associated with occurrence of cold- (e.g. subantarctic fur seal and warm-water (e.g. rough-toothed dolphin species in winter and summer, respectively. Inter-annual increases in stranding rate were observed for franciscana and South American fur seal and these are likely related to increased fishing effort and population growth, respectively. For subantarctic fur seal the stranding rate showed a slight decline while for bottlenose dolphin it remained steady. No significant year to year variation in stranding rate was observed for South American sea lion. The slight decrease in frequency of temperate/polar marine mammals and the increased occurrence of subtropical/tropical species since the late 1990s might be associated with environmental changes linked to

  8. Climate and humans set the place and time of Proboscidean extinction in late Quaternary of South America

    DEFF Research Database (Denmark)

    Lima-Ribeiro, Matheus Souza; Nogues, David Bravo; Terribile, Levi Carina

    2013-01-01

    of human hunting, but if climatic conditions were suitable like in Last Glacial Maximum (LGM), the time-for-extinction would be at least 3 times longer under the same human hunting pressures. Thus, our findings support the ``Broken Zig-Zag'' model and show that South American Proboscideans might have been...... (ENMs) and modeled the timing for extinction under human hunting scenario, and both variables were used to explain the extinction dynamics of Proboscideans during a full interglacial/glacial cycle (from 126 ka to 6 ka) in South America. We found a large contraction in the geographic range size of two...

  9. The coexistence of peace and conflict in South America: toward a new conceptualization of types of peace

    Directory of Open Access Journals (Sweden)

    Jorge Mario Battaglino

    2012-12-01

    Full Text Available South America's predominant democratic regimes and its increasing interdependence on regional trade have not precluded the emergence of militarized crises between Colombia and Venezuela or the revival of boundary claims between Chile and Peru. This way, how can we characterize a zone that, in spite of its flourishing democracy and dense economic ties, remain involved in territorial disputes for whose resolution the use of force has not yet been discarded? This article contends that existing classifications of zones of peace are not adequate to explain this unusual coexistence. Thus, its main purpose is to develop a new analytical category of regional peace for assessing this phenomenon: the hybrid peace. It aims to research the evolution of security systems in South America during the previous century and build a new, threefold classification of peace zones: negative peace zones, hybrid peace zones, and positive peace zones.

  10. Morphological and cytological diversity of goldenrods (Solidago L. and Euthamia Nutt. from south-western Poland

    Directory of Open Access Journals (Sweden)

    Szymura Magdalena

    2015-06-01

    Full Text Available Correlations between the morphology and cytology of invasive species and the effectiveness of invasion are among the most interesting questions in invasion ecology. Amongst exceptionally successful worldwide plant invaders, species of goldenrod (Solidago and Euthamia are considered. The main aim of the study was to compare the morphology (concerning life traits and cytology of the selected goldenrods occurring in south-western Poland with the effectiveness of their invasion. The results of the study, conducted in south-western Poland, showed that life traits of invasive Solidago and Euthamia taxa were clearly not connected with the effectiveness of invasion. The most widespread species, S. gigantea and S. altissima, had the highest ramets and uncommon species such as Euthamia graminifolia and S. virgaurea had short ramets. However, S. canadensis, which is tall, is also uncommon. The most frequent species (S. gigantea produced smaller inflorescence than less frequent species (S. altissima, S. canadensis and Euthamia graminifolia. The spread of particular taxa was also not connected with the ploidy level and DNA content.

  11. Lichens in the Urban Environment within South-East of Western Siberia, Russia

    Directory of Open Access Journals (Sweden)

    Ekaterina V. Romanova

    2013-12-01

    Full Text Available Lichen species diversity and trend of their distribution were studied in two big cities and fi ve towns in south-east of Western Siberia. In total of 348 species from 46 families and 98 genera were found in all studied urban and suburban areas. All local checklists are characterized by high degree of the lichen species similarity between each other and smaller lists are included in bigger ones on to 64-100%. Epiphytic lichens were the largest group in all studied areas and almost half of them were occupied two and more substrates. Crustose life-form and mesophytes prevailed everywhere. Share of sensitive lichens exceeded percent of tolerant ones in big cities and was lower than tolerant ones in smaller towns. The sixteen species were the most tolerant, commonly present everywhere and have been recognized as the key species for urban lichen synusiae within south-east of Western Siberia. Five zones have been determined with IP-mapping (mapping on the base of index of air pollution tolerance in studied areas: IP=3-5 is a “normal zone”, IP=5-7 is a “moderate exposure zone”, IP=7-9 is a “mixed zone”, IP=9-10 is a “struggle zone”, and fi nally – lichen-free zone. The most studied urban areas had got quite extensive lichen-free zone (up to 35% of their areas.

  12. Survey of blindness and low vision in Egbedore, South-Western Nigeria.

    Science.gov (United States)

    Kolawole, O U; Ashaye, A O; Adeoti, C O; Mahmoud, A O

    2010-01-01

    Developing efficient and cost-effective eye care programmes for communities in Nigeria has been hampered by inadequate and inaccurate data on blindness and low vision. To determine the prevalence and causes of blindness and low vision among adults 50 years and older in South-Western Nigeria in order to develop viable eye care programme for the community. Twenty clusters of 60 subjects of age 50 years and older were selected by systematic random cluster sampling. Information was collected and ocular examinations were conducted on each consenting subject. Data were recorded in specially designed questionnaire and analysed using descriptive statistical methods. Out of the 1200 subjects enrolled for the study, 1183(98.6%) were interviewed and examined. Seventy five (6.3%)) of the 1183 subjects were bilaterally blind and 223(18.9%) had bilateral low vision according to WHO definition of blindness and low vision. Blindness was about 1.6 times commoner in men than women. Cataract, glaucoma and posterior segment disorders were major causes of bilateral blindness. Bilateral low vision was mainly due to cataract, refractive errors and posterior segment disorders. The prevalence of blindness and low vision in this study population was high. The main causes are avoidable. Elimination of avoidable blindness and low vision calls for attention and commitment from government and eye care workers in South Western Nigeria.

  13. Reproductive and population parameters of spiny dogfish Squalus acanthias in the south-western Atlantic Ocean.

    Science.gov (United States)

    Colonello, J H; Cortés, F; Belleggia, M; Massa, A M

    2016-05-01

    The objective of this study was to estimate reproductive and population parameters of the spiny dogfish Squalus acanthias for the south-western Atlantic Ocean. In total, 2714 specimens (1616 males and 1098 females) were collected from surveys carried out using research vessels. Males ranged from 225 to 861 mm total length (LT ) and females from 235 to 925 mm LT . The size at maturity of females (651 mm) was significantly greater than that of males (565 mm). The maximum proportion of mature individuals (Pmax ) of the gestation ogive was 156 mm). The temporal and spatial co-occurrence of non-gravid adult females at different stages of ovarian development, as well as gravid females at all embryonic development stages would indicate that the female reproductive cycle in the south-western Atlantic Ocean is asynchronous. The results indicate that S. acanthias is susceptible to fishing pressure on account of its length at maturity, extended reproductive cycles and low fecundity. © 2016 The Fisheries Society of the British Isles.

  14. A check list of the spider fauna of the Western Soutpansberg, South Africa (Arachnida: Araneae

    Directory of Open Access Journals (Sweden)

    S.H. Foord

    2002-12-01

    Full Text Available By virtue of its geological history and geographical location the Soutpansberg constitutes a refuge for a high diversity of organisms. The Western Soutpansberg forms part of the Savanna Biome and is presently the area with the highest concentration of Natural Heritage Sites in South Africa. A unique private initiative is under way to improve its national and international conservation status in a bid to conserve the mountain. A checklist of the spider species of the Western Soutpansberg collected over a five-year period is presented. Forty-six families, represented by 109 genera and 127 species have been collected. Of the species collected, 81 (64 % were wandering spiders and 46 (36 % web builders. The Thomisidae have the highest number of species (15 followed by the Araneidae and the Salticidae with 10 species each. Ninety-six genera are represented by a single species. Ninety six percent of the species collected are new records for the area. This survey is the first for the area and forms part of the South African National Survey of Arachnida (SANSA.

  15. Health risk behaviours of stroke patients in the Western Cape, South Africa

    Directory of Open Access Journals (Sweden)

    D. Biggs

    2008-01-01

    Full Text Available Stroke is a leading cause of death and a major cause of disability globally. Individuals with physical disabilities, including thosewho have suffered a stroke are at risk of secondary complications due to the impact of their disability, which may be exacerbated by their lifestylechoices. The aim of the present study was to determine the health riskbehaviours and factors that influence these behaviours of stroke patients inthe Metropole Region of the Western Cape, South Africa. A cross – sectionalsurvey, utilizing a self-administered questionnaire on a convenient sampleof 417 stroke patients, was used to collect data. A sub-sample of 10 parti-cipants was purposively selected for in-depth, face-to-face interviews.Approximately forty percent (40.3% of the participants did not engage in physical exercise. While 30.2% smoked only9% abused alcohol. A significant association was found between age and smoking (p<0.002. Information gathered in the in-depth interviews revealed factors that influenced the behaviours of the participants. These factors includedlack of financial resources and lack of access to information. As participants were found to be at risk of secondarycomplications because of poor lifestyle choices, there is a clear need to implement health promotion programmes topromote well-ness enhancing behaviours in order to enhance the quality of health of patients who have suffered astroke in the Western Cape, South Africa.

  16. Ocean deformation processes at the Caribbean-North America-South America triple junction: Initial results of the 2007 ANTIPLAC marine survey

    Science.gov (United States)

    Benard, F.; Deville, E.; Le Drezen, E.; Loubrieu, B.; Maltese, L.; Patriat, M.; Roest, W.; Thereau, E.; Umber, M.; Vially, R.

    2007-12-01

    Marine geophysical data (multibeam and seismic lines) acquired in 2007 (ANTIPLAC survey) in the North-South Americas-Caribbean triple point (Central Atlantic, Barracuda and Tiburon ridges area), provide information about the structure, the tectonic processes and the timing of the deformation in this large diffuse zone of polyphase deformation. The deformation of the plate boundary between the north and south Americas is distributed on several structures located in the Atlantic plain, at the front of the Barbados accretionary prism. In this area of deformation of the Atlantic oceanic lithosphere, the main depressions and transform troughs are filled by Late Pliocene-Pleistocene turbidite sediments, especially in the Barracuda trough, north of Barracuda ridge. These sediments are not issued from the Lesser Antilles volcanic arc but they are sourced from the East, probably by the Orinoco turbidite distal system, through channels transiting in the Atlantic abyssal plain. These Late Pliocene- Quaternary sediments show locally spectacular evidences of syntectonic deformation. It can be shown notably that Barracuda ridge includes a pre-existing transform fault system which has been folded and uplifted very recently during Pleistocene times. This recent deformation has generate relieves up to 2 km high with associated erosion processes notably along the northern flank the Barracuda ridge. The subduction of these recently deformed ridges induces deformation of earlier structures within the Barbados accretionary prism. These asperities within the Atlantic oceanic lithosphere which is subducted in the Lesser Antilles active margin are correlated with the zone of intense seismic activity below the volcanic arc.

  17. Phylogeography and Sex-Biased Dispersal across Riverine Manatee Populations (Trichechus inunguis and Trichechus manatus) in South America

    OpenAIRE

    Satiz?bal, Paula; Mignucci-Giannoni, Antonio A.; Duch?ne, Sebasti?n; Caicedo-Herrera, Dalila; Perea-Sicchar, Carlos M.; Garc?a-D?vila, Carmen R.; Trujillo, Fernando; Caballero, Susana J.

    2012-01-01

    Phylogeographic patterns and sex-biased dispersal were studied in riverine populations of West Indian (Trichechus manatus) and Amazonian manatees (T. inunguis) in South America, using 410bp D-loop (Control Region, Mitochondrial DNA) sequences and 15 nuclear microsatellite loci. This multi-locus approach was key to disentangle complex patterns of gene flow among populations. D-loop analyses revealed population structuring among all Colombian rivers for T. manatus, while microsatellite data sug...

  18. A review of the nutritional content and technological parameters of indigenous sources of meat in South America.

    Science.gov (United States)

    Saadoun, A; Cabrera, M C

    2008-11-01

    Meat yields, proximate compositions, fatty acids compositions and technological parameters are reviewed for species which might be further developed as indigenous sources of meat in South America. These include the alpaca (Lama pacos), capybara (Hydrochoerus hydrochaeris), guanaco (Lama guanicoe), llama (Lama glama), nutria (Myocastor coypus), collared peccary (Tayassu tajacu), greater rhea (Rhea americana), lesser rhea (Rhea pennata), yacare (Caiman crocodilus yacare), tegu lizard (Tupinambis merianae) and green iguana (Iguana iguana).

  19. First case of New Delhi metallo-β-lactamase in Klebsiella pneumoniae from Ecuador: An update for South America

    OpenAIRE

    Daniel Romero-Alvarez; Jorge Reyes; Viviana Quezada; Carolina Satán; Nelson Cevallos; Sofía Barrera; Gabriel Trueba; Luis E. Escobar; José E. Villacís

    2017-01-01

    Objectives: To describe a clinical case of Klebsiella pneumoniae harboring a New Delhi metallo-β-lactamase (NDM) plasmid in Ecuador and to present a map of reports of NDM isolates in South America. Methods: The modified Hodge test, carbapenem inactivation method, imipenemâEDTA disk method (synergy), and Rapidec Carba NP test were used to identify antibiotic resistance mechanisms. The presence of resistance genes was explored with a conjugation assay, and molecular confirmation of NDM was per...

  20. Glaciation and Hydrologic Variability in Tropical South America During the Last 400,000 Years

    Science.gov (United States)

    Fritz, S. C.; Baker, P. A.; Seltzer, G. O.; Ekdahl, E. J.; Ballantyne, A.

    2005-12-01

    The expansion and contraction of northern continental ice sheets is a fundamental characteristic of the Quaternary. However, the extent of tropical glaciation is poorly constrained, particularly for periods prior to the Last Glacial Maximum (LGM). Similarly, the magnitude and timing of hydrologic variation in tropical South America is not clearly defined over multiple glacial cycles. Thus, the relative roles of global temperature change and insolation control of the South American Summer Monsoon (SASM) are unclear. We have reconstructed the timing of glaciation and precipitation variability in the tropical Andes of South America from drill cores from Lake Titicaca, Bolivia/Peru. The longest core (site LT01-2B, 235 m water depth) is 136 m and consists of four major silt-dominated units with high magnetic susceptibility, low organic carbon concentration, and no carbonate, which are indicative of extensive glacial activity in the cordillera surrounding the lake. These units alternate with laminated low-susceptibility units, with high carbonate and organic carbon concentrations, which reflect times when detrital input from the watershed was low and lake-level was lowered to below the outlet threshold, driving carbonate precipitation. Thus, the stratigraphy suggests that the core spans four major periods of glaciation and the subsequent interstadials. Core chronology is based on radiocarbon in the uppermost 25m, U-series dates on aragonite laminae, and tuning of the calcium carbonate stratigraphy in the lowermost sediments to the Vostok CO2 record. High-resolution (ca. 100 yr) sampling of sediments spanning the last glacial stage shows distinct millennial-scale variability from 20 - 65 kyr BP. This variability is evident in the periodic deposition of turbidites, which are characterized by low biogenic silica concentrations, elevated benthic diatom abundances, heavy carbon isotopic values, high C/N ratios, and an increase in mean grain size - a composite signal