Barcoding the butterflies of southern South America: Species delimitation efficacy, cryptic diversity and geographic patterns of divergence.

Science.gov (United States)

Lavinia, Pablo D; Núñez Bustos, Ezequiel O; Kopuchian, Cecilia; Lijtmaer, Darío A; García, Natalia C; Hebert, Paul D N; Tubaro, Pablo L

2017-01-01

Because the tropical regions of America harbor the highest concentration of butterfly species, its fauna has attracted considerable attention. Much less is known about the butterflies of southern South America, particularly Argentina, where over 1,200 species occur. To advance understanding of this fauna, we assembled a DNA barcode reference library for 417 butterfly species of Argentina, focusing on the Atlantic Forest, a biodiversity hotspot. We tested the efficacy of this library for specimen identification, used it to assess the frequency of cryptic species, and examined geographic patterns of genetic variation, making this study the first large-scale genetic assessment of the butterflies of southern South America. The average sequence divergence to the nearest neighbor (i.e. minimum interspecific distance) was 6.91%, ten times larger than the mean distance to the furthest conspecific (0.69%), with a clear barcode gap present in all but four of the species represented by two or more specimens. As a consequence, the DNA barcode library was extremely effective in the discrimination of these species, allowing a correct identification in more than 95% of the cases. Singletons (i.e. species represented by a single sequence) were also distinguishable in the gene trees since they all had unique DNA barcodes, divergent from those of the closest non-conspecific. The clustering algorithms implemented recognized from 416 to 444 barcode clusters, suggesting that the actual diversity of butterflies in Argentina is 3%-9% higher than currently recognized. Furthermore, our survey added three new records of butterflies for the country (Eurema agave, Mithras hannelore, Melanis hillapana). In summary, this study not only supported the utility of DNA barcoding for the identification of the butterfly species of Argentina, but also highlighted several cases of both deep intraspecific and shallow interspecific divergence that should be studied in more detail.

Anaglyph, South America

Science.gov (United States)

2003-01-01

landforms, including some broad areas of consistent topographic patterns that indicate the occurrence of simple erosional processes acting upon fairly uniform bedrock. Very smooth plateaus here are remnants of landforms most likely developed under geologic and environmental conditions much different than those present today. Fractures paralleling the coast are likely related to the opening of the Atlantic Ocean as South America drifted away from Africa, starting about 130 million years ago.To the southwest, broad lowlands host the Gran Chaco and Pampas regions. The depositional Gran Chaco drainages run almost exclusively from west to east from the Andes Mountains to the western edge of the Brazilian Highlands as a result of the much greater sediment supply from the Andes. Geologic processes on the Pampas are much more diverse, with stream erosion, stream deposition, subsidence, and wind processes all evident, even at the one-kilometer resolution shown here.Further south, Patagonia also displays these geologic processes plus more prominent volcanic features, including bumpy mesas, which are lava plateaus with small (and some large) volcanic cones. At its southern tip, of South America breaks into islands that include Tierra del Fuego and the Straits of Magellan.This anaglyph was created by deriving a shaded relief image from the SRTM data, draping it back over the SRTM elevation model, and then generating two differing perspectives, one for each eye. Illumination is from the north (top). When viewed through special glasses, the anaglyph is a vertically exaggerated view of the Earth's surface in its full three dimensions. Anaglyph glasses cover the left eye with a red filter and cover the right eye with a blue filter.Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture

USING SRTM TO QUANTIFY SIZE PARAMETERS AND SPATIAL DISTRIBUTION OF ENDORHEIC BASINS IN SOUTHERN SOUTH AMERICA

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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.

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.

Polychaeta Orbiniidae from Antarctica, the Southern Ocean, the Abyssal Pacific Ocean, and off South America.

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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.

Meteorology of the Southern Global Plume: African and South American Fires Pollute the South Pacific

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Guo, Z.; Chatfield, R. B.

1999-01-01

An immense global plume of CO meanders widely around the world in the Southern Hemisphere. It arises over Southern America and Africa and flows eastward. The first emissions are in tropical Brazil, and the plume circulates around the world to South America again. The plume was largely unexpected until there were aircraft studies made in NASA's Pacific Exploratory Mission - Tropics (Part A). This paper describes the meteorology of the Global Plume, as our simulation, with a synoptic model adapted to global transport, reveals it with a tracer-CO simulation. The observations and their simulation require a particular set of conditions of pollutant accumulation, cumulonimbus venting with required strengths at a narrow range of altitude. Additionally, a particular subtropical conduction region, over the Indian Ocean, Australia, and the westeRNmost South Pacific, relatively free of storms, appears to be a key part of the mechanism. These conclusions are the results of a synoptic reconstruction of the PEMT-A period, September- October, 1996.

Regional simulation of interannual variability over South America

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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.

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

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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.

Phylogeography of screaming hairy armadillo Chaetophractus vellerosus: Successive disjunctions and extinctions due to cyclical climatic changes in southern South America.

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Poljak, Sebastián; Ferreiro, Alejandro M; Chiappero, Marina B; Sánchez, Julieta; Gabrielli, Magalí; Lizarralde, Marta S

2018-01-01

Little is known about phylogeography of armadillo species native to southern South America. In this study we describe the phylogeography of the screaming hairy armadillo Chaetophractus vellerosus, discuss previous hypothesis about the origin of its disjunct distribution and propose an alternative one, based on novel information on genetic variability. Variation of partial sequences of mitochondrial DNA Control Region (CR) from 73 individuals from 23 localities were analyzed to carry out a phylogeographic analysis using neutrality tests, mismatch distribution, median-joining (MJ) network and paleontological records. We found 17 polymorphic sites resulting in 15 haplotypes. Two new geographic records that expand known distribution of the species are presented; one of them links the distributions of recently synonimized species C. nationi and C. vellerosus. Screaming hairy armadillo phylogeographic pattern can be addressed as category V of Avise: common widespread linages plus closely related lineages confined to one or a few nearby locales each. The older linages are distributed in the north-central area of the species distribution range in Argentina (i.e. ancestral area of distribution). C. vellerosus seems to be a low vagility species that expanded, and probably is expanding, its distribution range while presents signs of genetic structuring in central areas. To explain the disjunct distribution, a hypothesis of extinction of the species in intermediate areas due to quaternary climatic shift to more humid conditions was proposed. We offer an alternative explanation: long distance colonization, based on null genetic variability, paleontological record and evidence of alternance of cold/arid and temperate/humid climatic periods during the last million years in southern South America.

Availability of vitamin D photoconversion weighted UV radiation in southern South America.

Science.gov (United States)

Diaz, Susana; Vernet, Maria; Paladini, Alejandro; Fuenzalida, Humberto; Deferrari, Guillermo; Booth, Charles R; Cabrera, Sergio; Casiccia, Claudio; Dieguez, Maria; Lovengreen, Charlotte; Pedroni, Jorge; Rosales, Alejandro; Vrsalovic, Jazmin

2011-12-01

Ultraviolet radiation (UVR) plays a key role in several biological functions, including human health. Skin exposure to UVR is the main factor in vitamin D photoconversion. There is also evidence relating low levels of vitamin D with certain internal cancers, mainly colon, breast and prostate, as well as other diseases. Several epidemiological studies have shown an inverse relationship between the above-mentioned diseases and latitude, in accordance with the ultraviolet radiation latitudinal gradient. The aim of this study is to determine whether UV irradiance levels in the southern South America are sufficient to produce suitable levels of vitamin D year around. For this purpose, vitamin D photoconversion weighted-irradiance was analyzed between S.S. de Jujuy (24.17°S, 65.02°W) and Ushuaia (54° 50'S, 68° 18'W). In addition to irradiance, skin type and area of body exposed to sunlight are critical factors in vitamin D epidemiology. Due to a broad ethnic variability, it was assumed that the skin type in this region varies between II and V (from the most to the less sensitive). All sites except South Patagonia indicate that skin II under any condition of body area exposure and skin V when exposing head, hands, arms and legs, would produce suitable levels of vitamin D year round (except for some days in winter at North Patagonian sites). At South Patagonian sites, minimum healthy levels of vitamin D year round can be reached only by the more sensitive skin II type, if exposing head, hands, arms and legs, which is not a realistic scenario during winter. At these southern latitudes, healthy vitamin D levels would not be obtained between mid May and beginning of August if exposing only the head. Skin V with head exposure is the most critical situation; with the exception of the tropics, sun exposure would not produce suitable levels of vitamin D around winter, during a time period that varies with latitude. Analyzing the best exposure time during the day in order to

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

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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

Landsat TM inventory and assessment of waterbird habitat in the southern altiplano of South America

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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.

The Southern Hemisphere between 30 and 11 cal. kyr B.P.: a comparison between continental records from Africa, South America and Australia

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Sylvestre, F.; Williams, M. A.; Gasse, F.; Chalie, F.; Vincens, A.; David, W.

2006-12-01

The timing and amplitude of climate changes during the Last Glacial Maximum (LGM) and Termination I have led to considerable debate around the mechanisms driving the reorganisation of the global climate system and its regional expression. The LGM over the southern tropics and subtropics is still poorly understood and the interpretation of different proxies sometimes appears controversial. Here, we summarise the best, well-dated continental records spanning the interval 30-11 cal. kyr, from Africa south of the equator, Australia and South America. Due to the scarcity of the usable records, we had to decipher several proxies (pollen-inferred vegetation, diatom-inferred lake level, isotopes, sea-surface temperatures SST- in the surrounding oceans) and to consider all existing types of archives (wetlands, lakes, speleothems, (peri)glacial deposits, dunes and aeolian dusts), to characterize as completely as possible, the major features of the climate variability over the three continents. Regional similarities and divergences are pointed out, especially East-West asymmetry linked with oceanic currents and topography. The processes driving the observed temperature and hydrological changes are discussed focusing on the following questions: -How did monsoonal climates in the southern tropics respond to orbital forcing versus other glacial boundary conditions, e.g., sea-surface conditions, during the LGM? Example: several tropical lakes from southern Africa were low during the LGM probably in response to low SST. -How did the convergence zones (e.g. the Intertropical Convergence Zone ITCZ) have migrated through time and why? Example: in South America, LGM dryness in Amazonia has been associated with a southward migration of the ITCZ. -How did the extratropical, winter rainfall domain expand/retreat in response to meridian shifts of the Subtropical Westerly Jet and of the oceanic Subtropical Front, and to latitudinal thermal gradient in the Southern Ocean? Example: in

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

Phylogeography of screaming hairy armadillo Chaetophractus vellerosus: Successive disjunctions and extinctions due to cyclical climatic changes in southern South America.

Directory of Open Access Journals (Sweden)

Sebastián Poljak

Full Text Available Little is known about phylogeography of armadillo species native to southern South America. In this study we describe the phylogeography of the screaming hairy armadillo Chaetophractus vellerosus, discuss previous hypothesis about the origin of its disjunct distribution and propose an alternative one, based on novel information on genetic variability. Variation of partial sequences of mitochondrial DNA Control Region (CR from 73 individuals from 23 localities were analyzed to carry out a phylogeographic analysis using neutrality tests, mismatch distribution, median-joining (MJ network and paleontological records. We found 17 polymorphic sites resulting in 15 haplotypes. Two new geographic records that expand known distribution of the species are presented; one of them links the distributions of recently synonimized species C. nationi and C. vellerosus. Screaming hairy armadillo phylogeographic pattern can be addressed as category V of Avise: common widespread linages plus closely related lineages confined to one or a few nearby locales each. The older linages are distributed in the north-central area of the species distribution range in Argentina (i.e. ancestral area of distribution. C. vellerosus seems to be a low vagility species that expanded, and probably is expanding, its distribution range while presents signs of genetic structuring in central areas. To explain the disjunct distribution, a hypothesis of extinction of the species in intermediate areas due to quaternary climatic shift to more humid conditions was proposed. We offer an alternative explanation: long distance colonization, based on null genetic variability, paleontological record and evidence of alternance of cold/arid and temperate/humid climatic periods during the last million years in southern South America.

On the differences between Last Glacial Maximum and Mid-Holocene climates in southern South America simulated by PMIP3 models

Science.gov (United States)

Berman, Ana Laura; Silvestri, Gabriel E.; Tonello, Marcela S.

2018-04-01

Differences between climate conditions during the Last Glacial Maximum (LGM) and the Mid-Holocene (MH) in southern South America inferred from the state-of-the-art PMIP3 paleoclimatic simulations are described for the first time in this paper. The aim is to expose characteristics of past climate changes occurred without human influence. In this context, numerical simulations are an indispensable tool for inferring changes in near-surface air temperature and precipitation in regions where proxy information is scarce or absent. The analyzed PMIP3 models describe MH temperatures significantly warmer than those of LGM with magnitudes of change depending on the season and the specific geographic region. In addition, models indicate that seasonal mean precipitation during MH increased with respect to LGM values in wide southern continental areas to the east of the Andes Cordillera whereas seasonal precipitation developed in areas to the west of Patagonian Andes reduced from LGM to MH.

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.

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.

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

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.

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

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

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

South America, Shaded Relief and Colored Height

Science.gov (United States)

2003-01-01

occurrence of simple erosional processes acting upon fairly uniform bedrock. Very smooth plateaus here are remnants of landforms most likely developed under geologic and environmental conditions much different than those present today. Fractures paralleling the coast are likely related to the opening of the Atlantic Ocean as South America drifted away from Africa, starting about 130 million years ago.To the southwest, broad lowlands host the Gran Chaco and Pampas regions. The depositional Gran Chaco drainages run almost exclusively from west to east from the Andes Mountains to the western edge of the Brazilian Highlands as a result of the much greater sediment supply from the Andes. Geologic processes on the Pampas are much more diverse, with stream erosion, stream deposition, subsidence, and wind processes all evident, even at the one-kilometer resolution shown here.Further south, Patagonia also displays these geologic processes plus more prominent volcanic features, including bumpy mesas, which are lava plateaus with small (and some large) volcanic cones. At its southern tip South America breaks into islands that include Tierra del Fuego and the Straits of Magellan.Two visualization methods were combined to produce the image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the northwest-southeast direction, so that northwest slopes appear bright and southeast slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow and tan, to white at the highest elevations.Elevation data used in this image were acquired by the Shuttle Radar Topography Mission aboard the Space Shuttle Endeavour, launched on Feb. 11, 2000. SRTM used the same radar instrument that comprised the Spaceborne Imaging Radar-C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR) that flew twice on the Space Shuttle Endeavour in 1994. SRTM was designed to collect 3-D measurements of

Prevalence of Intimate Partner Violence Among South Asian Women Living in Southern Ontario.

Science.gov (United States)

Madden, Kim; Scott, Taryn; Sholapur, Naushin; Bhandari, Mohit

2016-08-01

Intimate partner violence (IPV) affects 4 in 10 women in North America in their lifetime and 13-27 % in the past year. The basis for estimates stems largely from studies involving Caucasian women. Less is known about other minority populations such as South Asian women. This study aimed to assess the prevalence of IPV in the past year among South Asian women living in Southern Ontario. We conducted a survey of South Asian women living in Southern Ontario. All adult self-identified South Asian women attending a cultural event celebrating South Asian women who could understand English or Punjabi were eligible to participate. The survey contained three IPV prevalence questions adapted from the Woman Abuse Screening Tool. A total of 188 women (45 % of potentially eligible women) participated. Nearly 1 in 5 women reported IPV within the past year (19.3 %, 95 % CI 13.9-26.1 %). In this study single women were significantly more likely to have experienced IPV in the past year compared to married women (p = 0.035). Self-identified immigrant and non-immigrant South Asian women in this sample of women living in Southern Ontario experienced violence in proportions comparable to the general population. Programs for women should ensure accessibility and support of all ethnicities given equivalent rates of violence in the community.

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

Antarctica: Arena for South American Cooperation or Conflict.

Science.gov (United States)

Child, Jack

A number of converging circumstances suggest that Antarctica may be a major object of geopolitical attention in South America in the decade to come. The Malvinas/Falklands crisis focused geopolitical attention on the South Atlantic and the chain of Southern (Austral) Islands which link the southern tip of South America to the Antarctic Peninsula.…

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.

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

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...

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.

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

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, ...

Multiproxy summer and winter surface air temperature field reconstructions for southern South America covering the past centuries

Energy Technology Data Exchange (ETDEWEB)

Neukom, R.; Grosjean, M.; Wanner, H. [University of Bern, Oeschger Centre for Climate Change Research (OCCR), Bern (Switzerland); University of Bern, Institute of Geography, Climatology and Meteorology, Bern (Switzerland); Luterbacher, J. [Justus Liebig University of Giessen, Department of Geography, Climatology, Climate Dynamics and Climate Change, Giessen (Germany); Villalba, R.; Morales, M.; Srur, A. [CONICET, Instituto Argentino de Nivologia, Glaciologia y Ciencias Ambientales (IANIGLA), Mendoza (Argentina); Kuettel, M. [University of Bern, Oeschger Centre for Climate Change Research (OCCR), Bern (Switzerland); University of Bern, Institute of Geography, Climatology and Meteorology, Bern (Switzerland); University of Washington, Department of Earth and Space Sciences, Seattle (United States); Frank, D. [Swiss Federal Research Institute WSL, Birmensdorf (Switzerland); Jones, P.D. [University of East Anglia, Climatic Research Unit, School of Environmental Sciences, Norwich (United Kingdom); Aravena, J.-C. [Centro de Estudios Cuaternarios de Fuego Patagonia y Antartica (CEQUA), Punta Arenas (Chile); Black, D.E. [Stony Brook University, School of Marine and Atmospheric Sciences, Stony Brook (United States); Christie, D.A.; Urrutia, R. [Universidad Austral de Chile Valdivia, Laboratorio de Dendrocronologia, Facultad de Ciencias Forestales y Recursos Naturales, Valdivia (Chile); D' Arrigo, R. [Earth Institute at Columbia University, Tree-Ring Laboratory, Lamont-Doherty Earth Observatory, Palisades, NY (United States); Lara, A. [Universidad Austral de Chile Valdivia, Laboratorio de Dendrocronologia, Facultad de Ciencias Forestales y Recursos Naturales, Valdivia (Chile); Nucleo Cientifico Milenio FORECOS, Fundacion FORECOS, Valdivia (Chile); Soliz-Gamboa, C. [Utrecht Univ., Inst. of Environmental Biology, Utrecht (Netherlands); Gunten, L. von [Univ. of Bern (Switzerland); Univ. of Massachusetts, Climate System Research Center, Amherst (United States)

2011-07-15

We statistically reconstruct austral summer (winter) surface air temperature fields back to ad 900 (1706) using 22 (20) annually resolved predictors from natural and human archives from southern South America (SSA). This represents the first regional-scale climate field reconstruction for parts of the Southern Hemisphere at this high temporal resolution. We apply three different reconstruction techniques: multivariate principal component regression, composite plus scaling, and regularized expectation maximization. There is generally good agreement between the results of the three methods on interannual and decadal timescales. The field reconstructions allow us to describe differences and similarities in the temperature evolution of different sub-regions of SSA. The reconstructed SSA mean summer temperatures between 900 and 1350 are mostly above the 1901-1995 climatology. After 1350, we reconstruct a sharp transition to colder conditions, which last until approximately 1700. The summers in the eighteenth century are relatively warm with a subsequent cold relapse peaking around 1850. In the twentieth century, summer temperatures reach conditions similar to earlier warm periods. The winter temperatures in the eighteenth and nineteenth centuries were mostly below the twentieth century average. The uncertainties of our reconstructions are generally largest in the eastern lowlands of SSA, where the coverage with proxy data is poorest. Verifications with independent summer temperature proxies and instrumental measurements suggest that the interannual and multi-decadal variations of SSA temperatures are well captured by our reconstructions. This new dataset can be used for data/model comparison and data assimilation as well as for detection and attribution studies at sub-continental scales. (orig.)

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.

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

Directory of Open Access Journals (Sweden)

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.

Atmospheric circulation associated with extreme generalized frosts persistence in central-southern South America

Energy Technology Data Exchange (ETDEWEB)

Mueller, Gabriela V. [Centro de Investigaciones Cientificas y Transferencia de Tecnologia a la Produccion, Diamante (CICYTTTP-CONICET), Diamante, Entre Rios (Argentina); Berri, Guillermo J. [Servicio Meteorologico Nacional - CONICET, Buenos Aires (Argentina)

2012-03-15

Generalized frosts (GF) in central-southern South America have a strong impact due to their spatial extension, and they are especially important when they become persistent. This paper aims at identifying the atmospheric circulation features that determine the extreme GF persistence, i.e. very persistent and without persistence, and the differences between them, during the 1961-1990 winters. Since the GF without persistence group outnumbers the other one, two subgroups are composed with events selected from winters with maximum and minimum frequency of GF occurrence, respectively. Additionally, the individual event of July 1988 within the very persistent GF group is analyzed due to its exceptional persistence. GF persistence is mainly conditioned by two large-scale dynamic factors. One is the Rossby wave train propagation across the Pacific Ocean, and the other one is the location with respect to the continent and the magnitude of the confluence in the jet entrance region in subtropical latitudes. A predominantly meridional Rossby wave train propagation with a confluence region to the west of the continent prior to the event favors GF with intermediate (null) persistence depending on the greater (lesser) jet acceleration. This is conditioned by the magnitude of the confluence, which, in turn, depends on the disposition of the wave train propagation pattern. Instead, an essentially zonal propagation with a confluence region to the east of the continent favors the GF persistence for several days, yet if there is no confluence the event does not persist. The greatest persistence of an event combines the confluence/diffluence of the jet entrance/exit region, which depends on the disposition with respect to the continent of the zonally propagating Rossby wave trains. (orig.)

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...

Multi-Decadal to Millennial Scale Holocene Hydrologic Variation in the Southern Hemisphere Tropics of South America

Science.gov (United States)

Ekdahl, E. J.; Fritz, S. C.; Baker, P. A.; Burns, S. J.; Coley, K.; Rigsby, C. A.

2005-12-01

Numerous sites in the Northern Hemisphere show multi-decadal to millennial scale climate variation during the Holocene, many of which have been correlated with changes in atmospheric radiocarbon production or with changes in North Atlantic oceanic circulation. The manifestation of such climate variability in the hydrology of the Southern Hemisphere tropics of South America is unclear, because of the limited number of records at suitably high resolution. In the Lake Titicaca drainage basin of Bolivia and Peru, high-resolution lacustrine records reveal the overall pattern of Holocene lake-level change, the influence of precessional forcing of the South American Summer Monsoon, and the effects of high-frequency climate variability in records of lake productivity and lake ecology. Precessional forcing of regional precipitation is evident in the Lake Titicaca basin as a massive (ca. 85 m) mid-Holocene decline in lake level beginning about 7800 cal yr BP and a subsequent rise in lake level after 4000 cal yr BP. Here we show that multi-decadal to millennial-scale climate variability, superimposed upon the envelope of change at orbital time scales, is similar in timing and pattern to the ice-rafted debris record of Holocene Bond events in the North Atlantic. A high-resolution carbon isotopic record from Lake Titicaca that spans the entire Holocene suggests that cold intervals of Holocene Bond events are periods of increased precipitation, thus indicating an anti-phasing of precipitation variation on the Altiplano relative to the Northern Hemisphere tropics. A similar pattern of variation is also evident in high-resolution (2-30 yr spacing) diatom and geochemical records that span the last 7000 yr from two smaller lakes, Lagos Umayo and Lagunillas, in the Lake Titicaca drainage basin.

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)

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.…

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.

Subduction in the Southern Caribbean

Science.gov (United States)

Levander, A.; Schmitz, M.; Bezada, M.; Masy, J.; Niu, F.; Pindell, J.

2012-04-01

The southern Caribbean is bounded at either end by subduction zones: In the east at the Lesser Antilles subduction zone the Atlantic part of the South American plate subducts beneath the Caribbean. In the north and west under the Southern Caribbean Deformed Belt accretionary prism, the Caribbean subducts under South America. In a manner of speaking, the two plates subduct beneath each other. Finite-frequency teleseismic P-wave tomography confirms this, imaging the Atlantic and the Caribbean subducting steeply in opposite directions to transition zone depths under northern South America (Bezada et al, 2010). The two subduction zones are connected by the El Pilar-San Sebastian strike-slip fault system, a San Andreas scale system. A variety of seismic probes identify where the two plates tear as they begin to subduct (Niu et al, 2007; Clark et al., 2008; Miller et al. 2009; Masy et al, 2009). The El Pilar system forms at the southeastern corner of the Antilles subduction zone by the Atlantic tearing from South America. The deforming plate edges control mountain building and basin formation at the eastern end of the strike-slip system. In northwestern South America the Caribbean plate tears, its southernmost element subducting at shallow angles under northernmost Colombia and then rapidly descending to transition zone depths under Lake Maracaibo (Bezada et al., 2010). We believe that the flat slab produces the Merida Andes, the Perija, and the Santa Marta ranges. The southern edge of the nonsubducting Caribbean plate underthrusts northern Venezuela to about the width of the coastal mountains (Miller et al., 2009). We infer that the underthrust Caribbean plate supports the coastal mountains, and controls continuing deformation.

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.

New insights into deglacial climate variability in tropical South America from molecular fossil and isotopic indicators in Lake Titicaca

Science.gov (United States)

Shanahan, T. M.; Hughen, K. A.; Fornace, K.; Baker, P. A.; Fritz, S. C.

2010-12-01

As one of the main centers of tropical convection, the South American Altiplano plays a crucial role in the long-term climate variability of South America. However, both the timing and the drivers of climate variability on orbital to millennial timescales remain poorly understood for this region. New data from molecular fossil (e.g., TEX86) and compound specific hydrogen isotope (D/H) analyses provide new insights into the climate evolution of this region over the last ~50 kyr. TEX86 temperature reconstructions suggest that the Altiplano warmed as early as 19- 21 kyr ago and proceeded rapidly, consistent with published evidence for an early retreat of LGM glaciers at this time at some locations. The early warming signal observed at Lake Titicaca also appears to be synchronous with continental temperature reconstructions at some sites in tropical Africa, but leads tropical SST changes by several thousands of years. Although the initiation of warming coincided with the peak in southern hemisphere summer insolation, subsequent temperature increases were accompanied by decreases in southern hemisphere insolation, suggesting a northern hemisphere driver for temperature changes in tropical South America. Preliminary D/H ratios from leaf waxes appear to support existing data suggesting that wet conditions prevailed until the late glacial/early Holocene and are broadly consistent with local southern hemisphere summer insolation forcing of the summer monsoon. These data suggest that temperature and precipitation changes during the last deglaciation were decoupled and that both local and extratropical drivers are important for controlling climate change in this region on orbital timescales.

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...

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

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.

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.

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.

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)

The Permo-Triassic uranium deposits of Southern Africa within the African-South American Gondwana framework

International Nuclear Information System (INIS)

Toens, P.D.; Le Roux, J.P.

1981-01-01

The discovery of uranium in the Permo-Triassic Gondwana in South America and Africa has served to highlight the intercontinental correlations. The purpose here is to examine the uranium deposits of Southern Africa in the light of the similarities that exist between the various Gondwana formations of the two continents. This hopefully will assist in gaining some understanding of the genesis of the uranium mineralization and the sedimentary environment in which such deposits are likely to occur. Between the Upper Carboniferous and the Jurassic a tectono-sedimentary terrain existed within Gondwanaland in which broadly similar conditions prevailed over large areas, thus producing numerous partly disconnected basins practically identical in character. The basal formations are composed of glacial tillite followed by a succession of sandstone and shale which attains a thickness of up to 12,000 m. Sedimentological studies confirm that major source areas composed largely of granitic and metamorphic rocks existed to the north and south of central South America and Southern Africa, as also in the divides between the basins. Uranium mineralization occurs sporadically throughout the succession and is usually restricted to palaeoriver channels containing carbon trash. There has been little subsequent enrichment and the Colorado model does not apply. With a few exceptions, the deposits tend to have a low overall uranium tenor and individual deposits are usually not very extensive in size. Collectively, however, they may eventually assume some importance. Uraniferous coals have been recorded from a number of localities and it is suggested that the significance of these deposits has as yet not been fully appreciated or investigated. (author)

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.

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

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

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

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.

Spatio-temporal variability of NDVI-precipitation over southernmost South America: possible linkages between climate signals and epidemics

Energy Technology Data Exchange (ETDEWEB)

Tourre, Y M [METEO-France, Meteopole, 42 Avenue Coriolis, 31057 Toulouse Cedex 1 (France); Jarlan, L [Centre d' Etudes Spatiales de la Biosphere (CESBIO), 18 avenue Edouard Belin, F-31401 Toulouse Cedex 4 (France); Lacaux, J-P [Universite Paul Sabatier (UPS), Observatoire Midi Pyrenees (OMP), 12 Avenue Edouard Belin, 31400 Toulouse (France); Rotela, C H [Instituto de Altos Estudios Espaciales ' Mario Gulich' , Comision Nacional de Actividades Espaciales (CONAE), Universidad Nacional de Cordoba (Argentina); Lafaye, M [CNES, DSP/ARP/AV, 18 Avenue Edouard Belin, F-31401 Toulouse Cedex 4 (France)

2008-10-15

Climate-environment variability affects the rates of incidence of vector-borne and zoonotic diseases and is possibly associated with epidemics outbreaks. Over southernmost South America the joint spatio-temporal evolution of climate-environment is analyzed for the 1982-2004 period. Detailed mapping of normalized difference vegetation index (NDVI) and rainfall variability are then compared to zones with preliminary epidemiological reports. A significant quasi-biennial signal (2.2- to 2.4-year periods, or QB) for joint NDVI-rainfall variability is revealed. From rotated EOFs, dominant NDVI patterns are partitioned according to their lead frequencies: (1) the 'QB group' (2.1-to 3-year periods) includes six modes over southern Brazil, Uruguay, northern-central Argentina (two modes), the southern Paraguay-northern Argentina border, and the Santa Cruz Province; (2) the QB1 (2.4- to 3-year periods) + quasi-quadrennial (QQ) mode over the Misiones Province; and (3) the QB2 (2.1- to 2.5-year periods) + QQ + inter-annual (IA) (3- to 7-year periods) two modes over south-eastern Argentina. Modes within the 'QB group' are positively correlated with global climate signals and SST. The Uruguayan mode is correlated with global ENSO (8-month lag) whilst the southern Entre-Rios/northern Buenos Aires provinces are correlated with central equatorial Pacific SSTs (3-month lag). The Santa Cruz (Patagonia) Province is most correlated with the Pacific South America (PSA) index and SST patterns (3-month lag) along the Antarctica circumpolar current. The spatial distribution of lead NDVI modes includes the Formosa, Misiones, Chaco and Buenos Aires provinces among others, known for being prone to vector-borne epidemics such as dengue fever, malaria, leishmaniasis (American cutaneous leishmaniasis or ACL), hantivirus, chagas and Argentine hemorrhagic fever (AHF). Some provinces also correspond to regions where lead NDVI PCs' modes are associated with high

Spatio-temporal variability of NDVI-precipitation over southernmost South America: possible linkages between climate signals and epidemics

Energy Technology Data Exchange (ETDEWEB)

Tourre, Y M [METEO-France, Meteopole, 42 Avenue Coriolis, 31057 Toulouse Cedex 1 (France); Jarlan, L [Centre d' Etudes Spatiales de la Biosphere (CESBIO), 18 avenue Edouard Belin, F-31401 Toulouse Cedex 4 (France); Lacaux, J-P [Universite Paul Sabatier (UPS), Observatoire Midi Pyrenees (OMP), 12 Avenue Edouard Belin, 31400 Toulouse (France); Rotela, C H [Instituto de Altos Estudios Espaciales ' Mario Gulich' , Comision Nacional de Actividades Espaciales (CONAE), Universidad Nacional de Cordoba (Argentina); Lafaye, M [CNES, DSP/ARP/AV, 18 Avenue Edouard Belin, F-31401 Toulouse Cedex 4 (France)

2008-10-15

Climate-environment variability affects the rates of incidence of vector-borne and zoonotic diseases and is possibly associated with epidemics outbreaks. Over southernmost South America the joint spatio-temporal evolution of climate-environment is analyzed for the 1982-2004 period. Detailed mapping of normalized difference vegetation index (NDVI) and rainfall variability are then compared to zones with preliminary epidemiological reports. A significant quasi-biennial signal (2.2- to 2.4-year periods, or QB) for joint NDVI-rainfall variability is revealed. From rotated EOFs, dominant NDVI patterns are partitioned according to their lead frequencies: (1) the 'QB group' (2.1-to 3-year periods) includes six modes over southern Brazil, Uruguay, northern-central Argentina (two modes), the southern Paraguay-northern Argentina border, and the Santa Cruz Province; (2) the QB1 (2.4- to 3-year periods) + quasi-quadrennial (QQ) mode over the Misiones Province; and (3) the QB2 (2.1- to 2.5-year periods) + QQ + inter-annual (IA) (3- to 7-year periods) two modes over south-eastern Argentina. Modes within the 'QB group' are positively correlated with global climate signals and SST. The Uruguayan mode is correlated with global ENSO (8-month lag) whilst the southern Entre-Rios/northern Buenos Aires provinces are correlated with central equatorial Pacific SSTs (3-month lag). The Santa Cruz (Patagonia) Province is most correlated with the Pacific South America (PSA) index and SST patterns (3-month lag) along the Antarctica circumpolar current. The spatial distribution of lead NDVI modes includes the Formosa, Misiones, Chaco and Buenos Aires provinces among others, known for being prone to vector-borne epidemics such as dengue fever, malaria, leishmaniasis (American cutaneous leishmaniasis or ACL), hantivirus, chagas and Argentine hemorrhagic fever (AHF). Some provinces also correspond to regions where lead NDVI PCs' modes are associated with high-frequency climate signals such as the

Spatio-temporal variability of NDVI-precipitation over southernmost South America: possible linkages between climate signals and epidemics

Science.gov (United States)

Tourre, Y. M.; Jarlan, L.; Lacaux, J.-P.; Rotela, C. H.; Lafaye, M.

2008-10-01

Climate-environment variability affects the rates of incidence of vector-borne and zoonotic diseases and is possibly associated with epidemics outbreaks. Over southernmost South America the joint spatio-temporal evolution of climate-environment is analyzed for the 1982-2004 period. Detailed mapping of normalized difference vegetation index (NDVI) and rainfall variability are then compared to zones with preliminary epidemiological reports. A significant quasi-biennial signal (2.2- to 2.4-year periods, or QB) for joint NDVI-rainfall variability is revealed. From rotated EOFs, dominant NDVI patterns are partitioned according to their lead frequencies: (1) the 'QB group' (2.1-to 3-year periods) includes six modes over southern Brazil, Uruguay, northern-central Argentina (two modes), the southern Paraguay-northern Argentina border, and the Santa Cruz Province; (2) the QB1 (2.4- to 3-year periods) + quasi-quadrennial (QQ) mode over the Misiones Province; and (3) the QB2 (2.1- to 2.5-year periods) + QQ + inter-annual (IA) (3- to 7-year periods) two modes over south-eastern Argentina. Modes within the 'QB group' are positively correlated with global climate signals and SST. The Uruguayan mode is correlated with global ENSO (8-month lag) whilst the southern Entre-Rios/northern Buenos Aires provinces are correlated with central equatorial Pacific SSTs (3-month lag). The Santa Cruz (Patagonia) Province is most correlated with the Pacific South America (PSA) index and SST patterns (3-month lag) along the Antarctica circumpolar current. The spatial distribution of lead NDVI modes includes the Formosa, Misiones, Chaco and Buenos Aires provinces among others, known for being prone to vector-borne epidemics such as dengue fever, malaria, leishmaniasis (American cutaneous leishmaniasis or ACL), hantivirus, chagas and Argentine hemorrhagic fever (AHF). Some provinces also correspond to regions where lead NDVI PCs' modes are associated with high-frequency climate signals such as the

Spatio-temporal variability of NDVI-precipitation over southernmost South America: possible linkages between climate signals and epidemics

International Nuclear Information System (INIS)

Tourre, Y M; Jarlan, L; Lacaux, J-P; Rotela, C H; Lafaye, M

2008-01-01

Climate-environment variability affects the rates of incidence of vector-borne and zoonotic diseases and is possibly associated with epidemics outbreaks. Over southernmost South America the joint spatio-temporal evolution of climate-environment is analyzed for the 1982-2004 period. Detailed mapping of normalized difference vegetation index (NDVI) and rainfall variability are then compared to zones with preliminary epidemiological reports. A significant quasi-biennial signal (2.2- to 2.4-year periods, or QB) for joint NDVI-rainfall variability is revealed. From rotated EOFs, dominant NDVI patterns are partitioned according to their lead frequencies: (1) the 'QB group' (2.1-to 3-year periods) includes six modes over southern Brazil, Uruguay, northern-central Argentina (two modes), the southern Paraguay-northern Argentina border, and the Santa Cruz Province; (2) the QB1 (2.4- to 3-year periods) + quasi-quadrennial (QQ) mode over the Misiones Province; and (3) the QB2 (2.1- to 2.5-year periods) + QQ + inter-annual (IA) (3- to 7-year periods) two modes over south-eastern Argentina. Modes within the 'QB group' are positively correlated with global climate signals and SST. The Uruguayan mode is correlated with global ENSO (8-month lag) whilst the southern Entre-Rios/northern Buenos Aires provinces are correlated with central equatorial Pacific SSTs (3-month lag). The Santa Cruz (Patagonia) Province is most correlated with the Pacific South America (PSA) index and SST patterns (3-month lag) along the Antarctica circumpolar current. The spatial distribution of lead NDVI modes includes the Formosa, Misiones, Chaco and Buenos Aires provinces among others, known for being prone to vector-borne epidemics such as dengue fever, malaria, leishmaniasis (American cutaneous leishmaniasis or ACL), hantivirus, chagas and Argentine hemorrhagic fever (AHF). Some provinces also correspond to regions where lead NDVI PCs' modes are associated with high-frequency climate signals such as the

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

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

Science.gov (United States)

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

2016-11-01

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 external inputs. We synthesised 242 references from peer-reviewed and grey literature published between 1945 and mid-2015 and analysed secondary data to examine the evidence on the ecosystem services provided by this grassland biodiversity hotspot and the way they are affected by land use changes and their drivers. The analysis followed the requirements of systematic review from the PRISMA statement (Moher et al 2009 Acad. Clin. Ann. Intern. Med. 151 264-9). The Pampas and Campos provide feed for 43 million heads of cattle and 14 million sheep. The biome is habitat of 4000 native plant species, 300 species of birds, 29 species of mammals, 49 species of reptiles and 35 species of amphibians. The soils of the region stock 5% of the soil organic carbon of Latin America on 3% of its area. Driven by high prices of soybean, the soybean area increased by 210% between 2000 and 2010, at the expense of 2 million ha (5%) of native grassland, mostly in the Pampas. Intensification of livestock production was apparent in two spatially distinct forms. In subregions where cropping increased, intensification of livestock production was reflected in an increased use of grains for feed as part of feedlots. In subregions dominated by native grasslands, stocking rates increased. The review showed that land use change and grazing regimes with low forage allowances were predominantly associated with negative effects on ecosystem service provision by reducing soil organic carbon stocks and the diversity of plants, birds and mammals, and by increasing soil erosion. We found little quantitative information on changes in the ecosystem services water provision, nutrient cycling and erosion control

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

The spider genus Kukulcania in South America (Araneae: Filistatidae): a redescription of K. brevipes (Keyserling) and new records of K. hibernalis (Hentz).

Science.gov (United States)

Brescovit, Antonio D; Santos, Adalberto J

2013-11-06

Two species of the spider genus Kukulcania are known from South America. Kukulcania brevipes (Keyserling), originally described from Peru, is here diagnosed, illustrated and redescribed, with several new records provided for eastern Peru and northern Chile. The synanthropic Kukulcania hibernalis (Hentz) is illustrated and diagnosed, with several new records extending the distribution of this species from northern Venezuela to southern Brazil.

Southern Forests: a Journal of Forest Science

African Journals Online (AJOL)

Southern Hemisphere Forestry Journal. ... The journal particularly encourages contributions from South America, Africa and tropical/subtropical ... Alternative eucalypts for commercial pulpwood production at moderately dry sites in the warm ...

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.

Regional drought in the southern of South America: physical aspects Seca regional no sul da América do Sul: aspectos físicos

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Juan Leonidas Minetti

2010-03-01

Full Text Available From the indices of monthly and annual climatic drought in six regions in southern South America and their associations with seventeen predictors, the probable physical causes of droughts are analyzed. These indices are used in operational climate monitoring and describe the atmospheric temperature and sea surface temperature (SST near South America. Subtropical anticyclone activity over both coasts of South America is one of the main predictors, together with its interaction with the continental depression and SST at the coast of Brazil. The highest predictability concentrates in November-December-May and the lowest in March, June and August. In the sub regional scale, the main predictors respond to atmospheric pressure anomalies in the Atlantic Ocean for Argentinean Northwest (NOA, SST in the Brazilian coast for Argentinean Northeast (NEA, anticyclonic conditions over the Pacific and Atlantic for the Central West (CO, the latter and their interaction with the continental depression for Humid Pampa (PH, anticyclonic activity over the Pacific for the Patagonia (PAT and trans cordillera circulation for Central Chile and Comahue (CHI.As causas físicas prováveis das secas em seis regiões no sul da América do Sul são analisadas, através de índices da seca climática mensal e em suas associações com dezessete preditores. Esses indices são usados no monitoramento operacional do clima, e descrevem a temperatura atmosférica e a temperatura de superfície do mar (TSM perto de América do Sul. A atividade do anticiclone subtropical sobre ambas as costas de América do Sul é um dos preditores principais, junto com sua interação com a depressão continental e a SST na costa do Brasil. A previsibilidade mais elevada concentra-se nos meses Novembro-Dezembro-Maio e a mais baixa, em março, junho e agosto. Na escala regional secundária, os principais preditores respondem às anomalias da pressão atmosférica sobre o Oceano Atlântico para

South African southern ocean research programme

CSIR Research Space (South Africa)

SASCAR

1987-01-01

Full Text Available This document describes the South African National Antarctic Research Programme's (SANARP) physical, chemical and biological Southern Ocean research programme. The programme has three main components: ecological studies of the Prince Edward Islands...

On the motion od the Caribbean relative to South-America: New results from GPS geodesy 1999-2012

Science.gov (United States)

De La Rosa, R.; Marquez, J.; Bravo, M.; Madriz, Y.; Mencin, D.; Wesnousky, S. G.; Molnar, P. H.; Bilham, R.; Perez, O. J.

2013-05-01

Our previous (1994-2006) collaborative GPS studies in southern Caribbean and northern South-America (SA) show that along its southern boundary in north-central and northeastern Venezuela (Vzla) the Caribbean plate (CP) slips easterly at ~20 mm/a relative to SA, and that in northwestern South-America slip-partitioning takes place resulting in 12 mm/a of dextral motion across the Venezuelan Andes, ~6 mm/a of which occur along the main trace of the NE-trending Bocono fault, and the rest is taken up by SE-subduction of the CP beneath northwestern SA. A series of new velocity vectors obtained in the region from GPS geodesy in 1999-2012 and their corresponding elastic modelings shows that in north-central Vzla part (~3 mm/a) of the C-SA relative dextral shear is taken up by the east-trending continental La Victoria fault, which runs ~50 kms south of San Sebastian fault off-shore and is sub-parallel to it, the later taken up the rest of the motion. The velocity we find for Aruba Is (~20 mm/y due ~east) is consistent with the motion predicted by the Euler pole (61,9° N; 75,7 °W; ω = 0,229 °/Ma) we previously calculated to describe the C-SA relative plate motion. New velocity vectors obtained across the Venezuelan Andes are consistent with a modeled surface velocity due to 12 mm/a of dextral shear below a locking depth of 14 km on one or more vertical N50°E striking faults located within the 100-km wide Andean ranges. The Andes also show a horizontal convergence rate of 2 to 4 mm/a suggesting an uplift rate of ~1.7 mm/a if thrust motion takes place on shallowly dipping faults parallel to the Andes.

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.

Approaching Southern Theory: Explorations of Gender in South African Education

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Epstein, Debbie; Morrell, Robert

2012-01-01

This article draws on the five other papers from South Africa in this issue of "Gender and Education" to consider how Southern theory has been developed and is developing in relation to gender and education in South Africa. We argue that Southern theory is not an on-the-shelf solution to global geopolitical inequalities but a work in…

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.

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...

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.

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.

The fossil record of South American short-faced bears (Ursidae, Tremarctinae)

OpenAIRE

Bond, Mariano; Tonni, Eduardo Pedro; Soibelzon, Leopoldo Héctor

2005-01-01

The present study includes a review of the geographic and stratigraphic distribution of short-faced bears (Ursidae, Tremarctinae) in South America. In addition, the authors discuss biogeographic hypotheses regarding the origin of South American tremarctines. The Tremarctinae subfamily is distributed exclusively in America, from Alaska to southern Patagonia. Its biochron comprises the temporal lapse between Late Miocene and recent times; the first record of Tremarctinae in North America corres...

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

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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.

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.

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.

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.

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.

Moderate climate signature in cranial anatomy of late holocene human populations from Southern South America.

Science.gov (United States)

Paula Menéndez, Lumila

2018-02-01

The aim of this study is to analyze the association between cranial variation and climate in order to discuss their role during the diversification of southern South American populations. Therefore, the specific objectives are: (1) to explore the spatial pattern of cranial variation with regard to the climatic diversity of the region, and (2) to evaluate the differential impact that the climatic factors may have had on the shape and size of the diverse cranial structures studied. The variation in shape and size of 361 crania was studied, registering 62 3D landmarks that capture shape and size variation in the face, cranial vault, and base. Mean, minimum, and maximum annual temperature, as well as mean annual precipitation, but also diet and altitude, were matched for each population sample. A PCA, as well as spatial statistical techniques, including kriging, regression, and multimodel inference were employed. The facial skeleton size presents a latitudinal pattern which is partially associated with temperature diversity. Both diet and altitude are the variables that mainly explain the skull shape variation, although mean annual temperature also plays a role. The association between climate factors and cranial variation is low to moderate, mean annual temperature explains almost 40% of the entire skull, facial skeleton and cranial vault shape variation, while annual precipitation and minimum annual temperature only contribute to the morphological variation when considered together with maximum annual temperature. The cranial base is the structure less associated with climate diversity. These results suggest that climate factors may have had a partial impact on the facial and vault shape, and therefore contributed moderately to the diversification of southern South American populations, while diet and altitude might have had a stronger impact. Therefore, cranial variation at the southern cone has been shaped both by random and nonrandom factors. Particularly, the

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.

Mio-Pliocene aridity in the south-central Andes associated with Southern Hemisphere cold periods.

Science.gov (United States)

Amidon, William H; Fisher, G Burch; Burbank, Douglas W; Ciccioli, Patricia L; Alonso, Ricardo N; Gorin, Andrew L; Silverhart, Perri H; Kylander-Clark, Andrew R C; Christoffersen, Michael S

2017-06-20

Although Earth's climate history is best known through marine records, the corresponding continental climatic conditions drive the evolution of terrestrial life. Continental conditions during the latest Miocene are of particular interest because global faunal turnover is roughly synchronous with a period of global glaciation from ∼6.2-5.5 Ma and with the Messinian Salinity Crisis from ∼6.0-5.3 Ma. Despite the climatic and ecological significance of this period, the continental climatic conditions associated with it remain unclear. We address this question using erosion rates of ancient watersheds to constrain Mio-Pliocene climatic conditions in the south-central Andes near 30° S. Our results show two slowdowns in erosion rate, one from ∼6.1-5.2 Ma and another from 3.6 to 3.3 Ma, which we attribute to periods of continental aridity. This view is supported by synchrony with other regional proxies for aridity and with the timing of glacial ‟cold" periods as recorded by marine proxies, such as the M2 isotope excursion. We thus conclude that aridity in the south-central Andes is associated with cold periods at high southern latitudes, perhaps due to a northward migration of the Southern Hemisphere westerlies, which disrupted the South American Low Level Jet that delivers moisture to southeastern South America. Colder glacial periods, and possibly associated reductions in atmospheric CO 2 , thus seem to be an important driver of Mio-Pliocene ecological transitions in the central Andes. Finally, this study demonstrates that paleo-erosion rates can be a powerful proxy for ancient continental climates that lie beyond the reach of most lacustrine and glacial archives.

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

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.

Environmental records from temperate glacier ice on Nevado Coropuna saddle, southern Peru

Directory of Open Access Journals (Sweden)

J. Herreros

2009-10-01

Full Text Available We investigated past climate variability and the zonal short and long-range transport of air masses in tropical South America using chemical, isotopic and palynological signals from a 42 m-long ice core recovered in 2003 from the saddle of the Nevado Coropuna, southern Peru (72°39´ W; 15°32´ S; 6080 m a.s.l.. We found that precipitation at this site depends mainly on the easterly circulation of air masses originated from the tropical Atlantic Ocean. Nevertheless, sporadic Pacific air masses arrivals, and strong cold waves coming from southern South America reach this altitude site. In spite of post-depositional effects, we were able to identify two strong ENSO (El Niño-Southern Oscillation event signatures (1982–1983 and 1992 and the eruptive activity of the nearby Sabancaya volcano (1994.

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

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

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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

The Solidarity Resettlement Programme, and alternatives, in Latin America

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María José Marcogliese

2017-02-01

Full Text Available For more than a decade, the countries in the Southern Cone of South America have had a regional Solidarity Resettlement Programme. The region’s states are also assessing alternative approaches to support refugee mobility within the framework of current migration agreements.

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,

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.

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

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.

Intravitreal Angiostrongylus cantonensis: first case report in South America

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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.

Natural gas integration in latin america: forward or backwards?

International Nuclear Information System (INIS)

Moutinho Dos Santos, E.; Oxilia Davalos, V.E.; Tadeu Werneck Faga, M.

2006-01-01

Throughout the 1990's to Year 2000, energy integration, and particularly natural gas integration, was seen as a major goal in the Southern Cone of South America, The regional perspective for energy was related to an even more challenging objective - Latin American economic integration, which was quickly moving forward by the constitution of MERCOSUR, the free trade zone built by Argentina, Brazil, Uruguay and Paraguay, and also having Bolivia and Chile as special partners. MERCOSUR was getting stronger and becoming a successful political project. Trade conflicts existed, but they were considered normal and nobody would disagree about the viability of MERCOSUR. By the beginning of the 21. Century, the economic integration process in South America was already advancing timidly as compared to the impetus from the beginning of 1990's. MERCOSUR started facing complex and almost insurmountable challenges after the numerous global financial crises (from 1998 to 2003) which had affected the economic balances in the region. Energy and gas integration in South America has equally lost perspective as fast as the importance of economic integration has declined. The economic crises in the region and poor energy policies have discouraged energy companies to invest. The paper presents this recent history of rising and falling in the concept of economic and energy integration in the Southern Cone of South America. Despite the abundance of energy resources, and particularly the plethora of recently discovered natural gas, the region has been experiencing systematic and important energy shortages, which may threaten its economic recovery. A stronger energy integration policy would help all the partner countries to reduce energy supply risks. Yet, energy (and gas) integration in the Southern Cone is still a complex long-term political project, which must involve all countries, but whose future perspective is unclear. It seems almost impossible to keep pushing forward this project

Leading El-Niño SST Oscillations around the Southern South American Continent

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Yu-Chen Hsu

2018-05-01

Full Text Available The inter-annual variations in the sea surface temperatures (SSTs of the tropical and subtropical Pacific Ocean have been widely investigated, largely due to their importance in achieving the sustainable development of marine ecosystems under a changing climate. The El Niño-Southern Oscillation (ENSO is a widely recognized variability. In the subpolar region in the southern hemisphere, the Antarctic Circumpolar Current (ACC is one of the main sources of the Peru Current. A change in the SST in the Southern Ocean may change the physical properties of the seawater in the tropical and subtropical Pacific Ocean. However, the variations in the SST in the Southern Ocean have rarely been addressed. This study uses a 147-year (1870–2016 dataset from the Met Office Hadley Centre to show that the SST anomalies (SSTAs in the oceans west and east of South America and the Antarctic Peninsula have strong positive (R = 0.56 and negative (R = −0.67 correlations with the Niño 3.4 SSTA, respectively. Such correlations are likely related to the changes in circulations of the ACC. We further show that, statistically, the temporal variations in the SSTAs of the ACC lead the Niño 3.4 SSTA by four to six months. Such findings imply that change in the strength of ENSO or circulation under the changing climate could change the climate in regions at higher latitudes as well.

Pleistocene changes in the fauna and flora of South america.

Science.gov (United States)

Vuilleumier, B S

1971-08-27

In recent years, the view that Pleistocene climatic events played a major role in the evolution of the biotas of southern, primarily tropical continents has begun to displace the previously held conviction that these areas remained relatively stable during the Quaternary. Studies of speciation patterns of high Andean plant and avian taxa (7-14) have led to the conclusion that Pleistocene climatic events were the factors that ultimately shaped the patterns now observed in the paramo-puna and the related Patagonian flora and fauna. The final uplift of the Andes at the end of the Tertiary automatically limits the age of the high Andean habitats and their biotas to the Quaternary. Within this period, the number of ecological fluctuations caused by the glaciations could easily have provided the mechanism behind the patterns now present in these habitats (Appendix, 1; Figs. 1 and 2; Table 1). In glacial periods, when vegetation belts, were lowered, organisms in the paramo-puna habitat were allowed to expand their ranges. In interglacial periods, these taxa were isolated on disjunct peaks, where differentiation could occur. At times of ice expansion, glacial tongues and lakes provided local barriers to gene exchange, whereas in warm, interglacial times, dry river valleys were a major deterrent to the interbreeding of populations on different mountains (Fig. 2; Table 2). A preliminary analysis of about 10 to 12 percent of the total South American avifauna (14), subsequent to the study of the high Andean biota, suggested that the birds of all the major habitats of the continent possess, with about equal frequency, similar stages of speciation. This correspondence in levels of evolution indicated that the avifauna of vegetation zones which were thought to have been more stable (for example, tropical rainforests) are as actively speciating as are those of the more recent paramo-puna habitats. More intensive work on lowland tropical taxa (16, 19-21) and recent work on montane

[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.

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...

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.

Patagonian and southern South Atlantic view of Holocene climate

Science.gov (United States)

Kaplan, M. R.; Schaefer, J. M.; Strelin, J. A.; Denton, G. H.; Anderson, R. F.; Vandergoes, M. J.; Finkel, R. C.; Schwartz, R.; Travis, S. G.; Garcia, J. L.; Martini, M. A.; Nielsen, S. H. H.

2016-06-01

We present a comprehensive 10Be chronology for Holocene moraines in the Lago Argentino basin, on the east side of the South Patagonian Icefield. We focus on three different areas, where prior studies show ample glacier moraine records exist because they were formed by outlet glaciers sensitive to climate change. The 10Be dated records are from the Lago Pearson, Herminita Península-Brazo Upsala, and Lago Frías areas, which span a distance of almost 100 km adjacent to the modern Icefield. New 10Be ages show that expanded glaciers and moraine building events occurred at least at 6120 ± 390 (n = 13), 4450 ± 220 (n = 7), 1450 or 1410 ± 110 (n = 18), 360 ± 30 (n = 5), and 240 ± 20 (n = 8) years ago. Furthermore, other less well-dated glacier expansions of the Upsala Glacier occurred between 1400 and ∼1000 and ∼2300 and ∼2000 years ago. The most extensive glaciers occurred over the interval from ∼6100 to ∼4500 years ago, and their margins over the last ∼600 years were well within and lower than those in the middle Holocene. The 10Be ages agree with 14C-limiting data for the glacier histories in this area. We then link southern South American, adjacent South Atlantic, and other Southern Hemisphere records to elucidate broader regional patterns of climate and their possible causes. In the early Holocene, a far southward position of the westerly winds fostered warmth, small Patagonian glaciers, and reduced sea ice coverage over the South Atlantic. Although we infer a pronounced southward displacement of the westerlies during the early Holocene, these conditions did not occur throughout the southern mid-high latitudes, an important exception being over the southwest Pacific sector. Subsequently, a northward locus and/or expansion of the winds over the Patagonia-South Atlantic sector promoted the largest glaciers between ∼6100 and ∼4500 years ago and greatest sea ice coverage. Over the last few millennia, the South Patagonian Icefield has experienced

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.

Increased drought impacts on temperate rainforests from southern South America: results of a process-based, dynamic forest model.

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Alvaro G Gutiérrez

Full Text Available Increased droughts due to regional shifts in temperature and rainfall regimes are likely to affect forests in temperate regions in the coming decades. To assess their consequences for forest dynamics, we need predictive tools that couple hydrologic processes, soil moisture dynamics and plant productivity. Here, we developed and tested a dynamic forest model that predicts the hydrologic balance of North Patagonian rainforests on Chiloé Island, in temperate South America (42°S. The model incorporates the dynamic linkages between changing rainfall regimes, soil moisture and individual tree growth. Declining rainfall, as predicted for the study area, should mean up to 50% less summer rain by year 2100. We analysed forest responses to increased drought using the model proposed focusing on changes in evapotranspiration, soil moisture and forest structure (above-ground biomass and basal area. We compared the responses of a young stand (YS, ca. 60 years-old and an old-growth forest (OG, >500 years-old in the same area. Based on detailed field measurements of water fluxes, the model provides a reliable account of the hydrologic balance of these evergreen, broad-leaved rainforests. We found higher evapotranspiration in OG than YS under current climate. Increasing drought predicted for this century can reduce evapotranspiration by 15% in the OG compared to current values. Drier climate will alter forest structure, leading to decreases in above ground biomass by 27% of the current value in OG. The model presented here can be used to assess the potential impacts of climate change on forest hydrology and other threats of global change on future forests such as fragmentation, introduction of exotic tree species, and changes in fire regimes. Our study expands the applicability of forest dynamics models in remote and hitherto overlooked regions of the world, such as southern temperate rainforests.

Increased drought impacts on temperate rainforests from southern South America: results of a process-based, dynamic forest model.

Science.gov (United States)

Gutiérrez, Alvaro G; Armesto, Juan J; Díaz, M Francisca; Huth, Andreas

2014-01-01

Increased droughts due to regional shifts in temperature and rainfall regimes are likely to affect forests in temperate regions in the coming decades. To assess their consequences for forest dynamics, we need predictive tools that couple hydrologic processes, soil moisture dynamics and plant productivity. Here, we developed and tested a dynamic forest model that predicts the hydrologic balance of North Patagonian rainforests on Chiloé Island, in temperate South America (42°S). The model incorporates the dynamic linkages between changing rainfall regimes, soil moisture and individual tree growth. Declining rainfall, as predicted for the study area, should mean up to 50% less summer rain by year 2100. We analysed forest responses to increased drought using the model proposed focusing on changes in evapotranspiration, soil moisture and forest structure (above-ground biomass and basal area). We compared the responses of a young stand (YS, ca. 60 years-old) and an old-growth forest (OG, >500 years-old) in the same area. Based on detailed field measurements of water fluxes, the model provides a reliable account of the hydrologic balance of these evergreen, broad-leaved rainforests. We found higher evapotranspiration in OG than YS under current climate. Increasing drought predicted for this century can reduce evapotranspiration by 15% in the OG compared to current values. Drier climate will alter forest structure, leading to decreases in above ground biomass by 27% of the current value in OG. The model presented here can be used to assess the potential impacts of climate change on forest hydrology and other threats of global change on future forests such as fragmentation, introduction of exotic tree species, and changes in fire regimes. Our study expands the applicability of forest dynamics models in remote and hitherto overlooked regions of the world, such as southern temperate rainforests.

George Kubler Shifting South: Architecture History Following Geopolitics

Directory of Open Access Journals (Sweden)

Sousa Santos, Eliana

2016-07-01

Full Text Available This essay aims to present the shifting relations between North America and the South - South America and the South of Europe - through the work of the historian George Kubler. At the beginning of his career as a scholar, Kubler was invited by the Department of State to participate in a conference on inter-American relations. Later, with the positioning of the United States in World War II, the transatlantic relationship between the US and Europe became more prominent. Kubler’s research interests followed this change: His research shift from South America to peripheral Southern Europe reflects an availability of funding given his country's geopolitical interests. So far, artists and other scholars have praised Kubler’s vast work regarding the art and architecture of different 'Souths' mainly as a sign of 'nonalignment' and of his attention to the condition of peripheral countries.

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.

Natural gas integration in Latin America: end of a dream?

International Nuclear Information System (INIS)

Moutinho dos Santos, E.; Oxilia Davalos, V.E.; Tadeu Werneck Faga, M.

2007-01-01

Throughout the 1990's to year 2000, energy integration, and particularly natural gas integration, was seen as a major goal in the southern cone of South America. The regional perspective for energy was related to an even more challenging objective - Latin American economic integration, which was quickly moving forward by the constitution of Mercosur, the free trade zone built by Argentina, Brazil, Uruguay and Paraguay, and also having Bolivia and Chile as special partners. Mercosur was getting stronger and becoming a successful political project. Trade conflicts existed, but they were considered normal and nobody would disagree about the viability of Mercosur. By the beginning of the 21. century, the economic integration process in South America was already advancing timidly as compared to the impetus from the beginning of 1990's. Mercosur started facing complex and almost insurmountable challenges after the numerous global financial crises (from 1998 to 2003) had affected the economic balances in the region. Energy and gas integration in South America has equally lost perspective as fast as the importance of economic integration has declined. The economic crises in the region and poor energy policies have discourage energy companies to invest. The paper presents this recent history of rise and fall in the concept of economic and energy integration in the southern cone of South America. Despite the abundance of energy resources, and particularly the plethora of recently discovered natural gas, the region has been experiencing systematic and important energy shortages, which may threaten its economic recovery. A stronger energy integration policy would help all the partner countries to reduce energy supply risks. Yet, energy (and gas) integration in the southern cone is still a complex long-term political project, which must involve all countries, but whose future perspective is unclear. It seems almost impossible to keep pushing forward this project without

Late Cretaceous-recent tectonic assembly of diverse crustal blocks in Central America, the Nicaraguan Rise, the Colombian Basin and northern South America as seen on a 1600-km-long, geologic and structural transect

Science.gov (United States)

Sanchez, J.; Mann, P.

2015-12-01

We have constructed a 1600-km-long transect from northern Honduras to northern Colombia that crosses northeastward-striking crustal blocks using a combination of offshore seismic data, gravity and magnetic data, well subsidence information, nearby outcrop information, and results from previous thermochronological, geochronological, geochemical and paleostress studies. The transect defines three major crustal and structural provinces: 1) Precambrian-Paleozoic, Chortis continental block whose northern edge is defined by the North America-Caribbean plate boundary. Events in this ~20-25-km-thick province include two major unconformities at the top of the Cretaceous and Eocene, associated southeast-dipping thrust faults related to collision of the Great Arc of the Caribbean (GAC) and Caribbean Large Igneous Province (CLIP) with the Chortis continental block. A third event is Eocene to recent subsidence and transtensional basins formed during the opening of the Cayman trough; 2) Late Cretaceous GAC and CLIP of oceanic arc and plateau origin, whose northern, deformed edge corresponds to the mapped Siuna belt of northern Nicaragua. This crustal province has a ~15-20-km-thick crust and is largely undeformed and extends across the Lower Nicaraguan Rise, Hess fault, to the southern limit of the Colombian basin where about 300 km of this province has been subducted beneath the accretionary wedge of the South Caribbean deformed belt of northwestern South America; and 3) Eocene to recent accretionary prism and intramontane basins on continental crust of northern South America, where Miocene accelerated exhumation and erosion of Paleogene and Cretaceous rocks reflect either shallow subduction of the CLIP or the Panama collisional event to the southwest.

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.

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

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.

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 ...

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.

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, ...

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.

Lead Toxicosis in a Southern Ground Hornbill Bucorvus leadbeateri in South Africa.

Science.gov (United States)

Koeppel, Katja N; Kemp, Lucy V

2015-12-01

The southern ground hornbill (Bucorvus leadbeateri) has been classified as globally vulnerable and, in South Africa, regionally endangered, with a negative population trend. Factors contributing to the population decline in South Africa are poisoning, electrocution, and illegal capture for trade, coupled with slow reproductive rates and extensive habitat requirements. Lead toxicosis is a previously undescribed threat for the population. An adult southern ground hornbill presented with acute lead toxicosis due to lead particles in the gizzard, which required intensive treatment. Two other hornbills were likely exposed. The source of the lead in these cases was likely a carcass of a porcupine that was killed with lead shot. This report highlights the importance of the use of lead-free ammunition within the habitat of the southern ground hornbill in South Africa.

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…

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.

A New Eocene Casquehead Lizard (Reptilia, Corytophanidae from North America.

Directory of Open Access Journals (Sweden)

Jack L Conrad

Full Text Available A new fossil showing affinities with extant Laemanctus offers the first clear evidence for a casquehead lizard (Corytophanidae from the Eocene of North America. Along with Geiseltaliellus from roughly coeval rocks in central Europe, the new find further documents the tropical fauna present during greenhouse conditions in the northern mid-latitudes approximately 50 million years ago (Ma. Modern Corytophanidae is a neotropical clade of iguanian lizards ranging from southern Mexico to northern South America.

Study of changes in the lineament structure, caused by earthquakes in South America by applying the lineament analysis to the Aster (Terra) satellite data

Science.gov (United States)

Arellano-Baeza, A. A.; Zverev, A. T.; Malinnikov, V. A.

The region between Southern Peru and Northern Chile is one of the most seismically and volcanically active regions in South America. This is caused by a constant subduction of the South American Plate, converging with the Nazca Plate in the extreme North of Chile. We used the 15 and 30 m resolution satellite images, provided by the ASTER (VNIR and SWIR) instrument onboard the Terra satellite to study changes in the geological faults close to earthquake epicenters in southern Peru. Visible and infrared spectral bands were analysed using “The Lineament Extraction and Stripes Statistic Analysis” (LESSA) software package to examine changes in the lineament features and stripe density fields caused by seismic activity. We used the satellite images 128 and 48 days before and 73 days after a 5.2 Richter scale magnitude earthquake. The fact that the seasonal variations in the South of Peru and North of Chile are very small, and the vegetation is very limited, allowed us to establish substantial changes in the lineament and the stripe density field features. We develop a methodology that allows to evaluate the seismic risk in this region for the future.

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

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

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...

Mesozoic Compressional Folds of the Nansha Waters, Southern South China Sea

Science.gov (United States)

Zhu, R.; Liu, H.; Yao, Y.; Wang, Y.

2017-12-01

As an important part of the South China Sea, the southern margin of the South China Sea is fundamental to understand the interaction of the Eurasian, Pacific and Indian-Australian plates and the evolution of the South China Sea. Some multi-channel seismic profiles of the Nansha waters together with published drillings and dredge data were correlated for interpretation. The strata of the study region can be divided into the upper, middle and lower structural layers. The upper and middle structural layers with extensional tectonics are Cenozoic; the lower structural layer suffered compression is Mesozoic. Further structural restoration was done to remove the Cenozoic tectonic influence and to calculate the Mesozoic tectonic compression ratios. The results indicate that two diametrically opposite orientations of compressive stress, S(S)E towards N(N)W orientation and N(N)W towards S(S)E orientation respectively, once existed in the lower structural layer of the study area and shared the same variation trend. The compression ratio values gradually decrease both from the north to the south and from the west to the east in each stress orientation. The phenomena may be related to the opening of the proto-South China Sea (then located in south of the Nansha block) and the rate of the Nansha block drifted northward in Late Jurassic to Late Cretaceous, which had pushed the Nansha block drifted northward until it collided and sutured with the Southern China Margin. Thus the opening of the present-day South China Sea may be related to this suture zone, which was tectonically weakness zone.Key words: Mesozoic compression; structural restoration; proto-South China Sea; Nansha waters; Southern South China Sea; Acknowledgements: The work was granted by the National Natural Science Foundation of China (Grant Nos. 41476039, 91328205, 41576068 and 41606080).

[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.

Biogeographic congruence in the south Pacific

DEFF Research Database (Denmark)

Seberg, Ole

1991-01-01

Ever since J. D. Hooker's famous 'Introductory Essay' to Flora NOVE-Zelandise, a classical problem in biogeography has been to give a casual explanation of southern hemisphere distribution patterns. An attempt is made to see whether the cladograms for the circum-Pacific areas (South America, New ...

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.

The Gondwanan connection - Southern temperate Amanita lineages and the description of the first sequestrate species from the Americas.

Science.gov (United States)

Truong, Camille; Sánchez-Ramírez, Santiago; Kuhar, Francisco; Kaplan, Zachary; Smith, Matthew E

2017-08-01

Amanita is a diverse and cosmopolitan genus of ectomycorrhizal fungi. We describe Amanita nouhrae sp. nov., a new hypogeous ('truffle-like') species associated with Nothofagus antarctica in northern Patagonia. This constitutes the first report of a sequestrate Amanita from the Americas. Thick-walled basidiospores ornamented on the interior spore wall ('crassospores') were observed consistently in A. nouhrae and its sister epigeous taxon Amanita morenoi, a rarely collected but apparently common species from northern Patagonia that has sometimes been misidentified as the Australian taxon Amanita umbrinella. Nuclear 18S and 28S ribosomal DNA and mitochondrial 16S and 26S DNA placed these two species in a southern temperate clade within subgenus Amanita, together with other South American and Australian species. Based on a dated genus-level phylogeny, we estimate that the southern temperate clade may have originated near the Eocene/Oligocene boundary (ca. 35 Ma ± 10 Ma). This date suggests a broadly distributed ancestor in the Southern Hemisphere, which probably diversified as a result of continental drift, as well as the initiation of the Antarctic glaciation. By comparison, we show that this clade follows an exceptional biogeographic pattern within a genus otherwise seemingly dominated by Northern Hemisphere dispersal. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.

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)

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.

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

The Pleistocene biogeography of eastern North America: A nonmigration scenario for deciduous forest

Energy Technology Data Exchange (ETDEWEB)

Loehle, C. [Argonne National Lab., IL (United States). Environmental Research Div.; Iltis, H. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Botany

1998-12-31

The current reconstruction of the vegetation of eastern North America at the last glacial maximum postulates a very wide zone of tundra and boreal forest south of the ice. This reconstruction requires that the deciduous forest retreated far to the south. The authors believe that this reconstruction is seriously in error. Geologic evidence for glacial activity or tundra is absent from the southern Appalachians. Positive evidence for boreal forest is based on pollen identifications for Picea, Betula, and Pinus, when in reality southern members of these genera have pollen that cannot be distinguished from that of northern members. Further, pollen of typical southern species such as oaks and hickories occurs throughout profiles that past authors had labeled boreal. Pollen evidence for a far southern deciduous forest refuge is lacking. Data on endemics are particularly challenging for the scenario in which deciduous forest migrated to the south and back. The southern Appalachian region is rife with endemics that are often extreme-habitat specialists unable to migrate. The previously glaciated zone is almost completely lacking in endemics. Outlier populations, range boundaries, and absence of certain hybrids all argue against a large boreal zone. The new reconstruction postulates a cold zone no more than 75--100 miles wide south of the ice in the East.

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.

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.

Andes hantavirus variant in rodents, southern Amazon Basin, Peru.

Science.gov (United States)

Razuri, Hugo; Tokarz, Rafal; Ghersi, Bruno M; Salmon-Mulanovich, Gabriela; Guezala, M Claudia; Albujar, Christian; Mendoza, A Patricia; Tinoco, Yeny O; Cruz, Christopher; Silva, Maria; Vasquez, Alicia; Pacheco, Víctor; Ströher, Ute; Guerrero, Lisa Wiggleton; Cannon, Deborah; Nichol, Stuart T; Hirschberg, David L; Lipkin, W Ian; Bausch, Daniel G; Montgomery, Joel M

2014-02-01

We investigated hantaviruses in rodents in the southern Amazon Basin of Peru and identified an Andes virus variant from Neacomys spinosus mice. This finding extends the known range of this virus in South America and the range of recognized hantaviruses in Peru. Further studies of the epizoology of hantaviruses in this region are warranted.

Andes Hantavirus Variant in Rodents, Southern Amazon Basin, Peru

OpenAIRE

Razuri, Hugo; Tokarz, Rafal; Ghersi, Bruno M.; Salmon-Mulanovich, Gabriela; Guezala, M. Claudia; Albujar, Christian; Mendoza, A. Patricia; Tinoco, Yeny O.; Cruz, Christopher; Silva, Maria; Vasquez, Alicia; Pacheco, Víctor; Ströher, Ute; Guerrero, Lisa Wiggleton; Cannon, Deborah

2014-01-01

We investigated hantaviruses in rodents in the southern Amazon Basin of Peru and identified an Andes virus variant from Neacomys spinosus mice. This finding extends the known range of this virus in South America and the range of recognized hantaviruses in Peru. Further studies of the epizoology of hantaviruses in this region are warranted.

The upper and lower Thvera sedimentary geomagnetic reversal records from southern Sicily

NARCIS (Netherlands)

Hoof, A.A.M. van; Langereis, C.G.

1992-01-01

Detailed paleomagnetic records of the upper and lower Thvera polarity transitions have been determined from Pliocenc marine marls in southern Sicily. The dominant magnetic mineral is fine grained magnetite. The two transitions have VGP paths following a great circle passing South America and the

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.

Convergence of gas and electricity markets in the Southern Cone of Latin America

International Nuclear Information System (INIS)

Offant, P.; Giorno, D.

2002-01-01

Around the world, the growing use of natural gas for electric power generation is leading to an increasing inter-dependency between gas and power markets. This phenomenon, generally known as convergence, has tremendous implications for governments, regulatory agencies, energy companies and consumers. Countries of the Southern Cone of Latin America, which have been precursors in creating competitive electricity markets and opening their power sector to private investments, and which are increasingly relying on natural gas to expand their power generation base, provide a valuable example of how the gas-power convergence process develops in a de-regulated environment, with a beneficial impact for the consumer. This paper provides an overview of the past, present and potential status of the convergence process between the gas and power markets in the Southern Cone of Latin America, and addresses the challenges and opportunities arising from this process. Taking into account a recent slowdown in the regional convergence process, it offers in closing remarks alternative tools to re-dynamize such process. (authors)

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...

SOUTH POL: Revealing the Polarized Southern Sky

Science.gov (United States)

Magalhaes, Antonio Mario Mario; Ramírez, Edgar; Ribeiro, Nadili; Seriacopi, Daiane; Rubinho, Marcelo; Ferrari, Tiberio; Rodrigues, Claudia; Schoenell, William; Herpich, Fabio; Pereyra, Antonio

2018-01-01

SOUTH POL will be a survey of the Southern sky in optical polarized light. It will use a newly built polarimeter for T80-S, an 84 cm robotic telescope installed at Cerro Tololo (CTIO), Chile. It will initially cover the sky South of declination -15 deg with a polarimetric accuracy Solar System.The polarimeter has just been commissioned in mid-November, 2017. The data reduction pipeline has already been built. We will describe the instrument and the data reduction, as well as a few of the science cases. The survey is expected to begin midway through the 1st semester of 2018. Both catalog data and raw images will be made available.

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.

The Influence of Volcanic Eruptions on the Climate of Tropical South America During the Last Millennium in an Isotope-Enabled General Circulation Model

Science.gov (United States)

Colose, Christopher M.; LeGrande, Allegra N.; Vuille, Mathias

2016-01-01

Currently, little is known on how volcanic eruptions impact large-scale climate phenomena such as South American paleo-intertropical Convergence Zone (ITCZ) position and summer monsoon behavior. In this paper, an analysis of observations and model simulations is employed to assess the influence of large volcanic eruptions on the climate of tropical South America. This problem is first considered for historically recent volcanic episodes for which more observations are available but where fewer events exist and the confounding effects of El Niño-Southern Oscillation (ENSO) lead to inconclusive interpretation of the impact of volcanic eruptions at the continental scale. Therefore, we also examine a greater number of reconstructed volcanic events for the period 850 CE to present that are incorporated into the NASA GISS ModelE2-R simulation of the last millennium. An advantage of this model is its ability to explicitly track water isotopologues throughout the hydrologic cycle and simulating the isotopic imprint following a large eruption. This effectively removes a degree of uncertainty associated with error-prone conversion of isotopic signals into climate variables, and allows for a direct comparison between GISS simulations and paleoclimate proxy records. Our analysis reveals that both precipitation and oxygen isotope variability respond with a distinct seasonal and spatial structure across tropical South America following an eruption. During austral winter, the heavy oxygen isotope in precipitation is enriched, likely due to reduced moisture convergence in the ITCZ domain and reduced rainfall over northern South America. During austral summer, however, more negative values of the precipitation isotopic composition are simulated over Amazonia, despite reductions in rainfall, suggesting that the isotopic response is not a simple function of the "amount effect". During the South American monsoon season, the amplitude of the temperature response to volcanic forcing is

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.

The Mysterious Southern Torque

Science.gov (United States)

McDowell, M. S.

2004-05-01

Something weird happened to twist the southern hemisphere out of alignment with the northern, as evidenced by the positions of the mountain ranges of North and South America, the Atlantic MAR, and the closure of West Africa to North America - all smooth were the torque reversed. What happened, and when, and why? We identify a number of global "cracks" of almost exactly the same length and direction, with some, even more peculiarly, turning the same angle, and proceeding an equal distance in the new direction. The Emperor-Hawaiian chain, the Louisville chain and the west coast of North America, as examples, are essentially parallel. Their northerly legs follow the angle of the axis of orbital ellipse. But then they all make equal 45 degree easterly bends, to 17.5 NW, and continue on, still parallel, for very similar distances. It is the same at the north coast of South America, and the mid-section of the MAR from 46W to 12W. It is the distance from the Cameroons to Kenya, from the south end of the Red Sea to the SE Indian Ridge at the Nema Fracture zone, from west to east of the Nazca plate.What is all this? Coincidence? Seeing things? Researchers have attributed plate motion or hot spot motion or both or absolutely none, to all of the above. Geophysicists have dated the surfaces from Archean to Pleistocene by all possible scientific means, certainly no possible correlation can be made. Yet we postulate the physical reality can be demonstrated. It is so global a phenomenon that it is well beyond what a hot spot or a plate could do. Even a really tremendous impact would have trouble making such precise geometric arrangements. So what is it - perhaps the angle of rotation, or the inertia of northern hemisphere mass above the geoid? And if so, then, what changed it? It would seem that some huge imbalance occurred. Suppose the whole bottom blew out of the southern hemisphere, and the center of mass drastically altered. Suppose some unknown universal force changed our

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)

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...

The Cambrian-Ordovician rocks of Sonora, Mexico, and southern Arizona, southwestern margin of North America (Laurentia): chapter 35

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Page, William R.; Harris, Alta C.; Repetski, John E.; Derby, James R.; Fritz, R.D.; Longacre, S.A.; Morgan, W.A.; Sternbach, C.A.

2013-01-01

Cambrian and Ordovician shelf, platform, and basin rocks are present in Sonora, Mexico, and southern Arizona and were deposited on the southwestern continental margin of North America (Laurentia). Cambrian and Ordovician rocks in Sonora, Mexico, are mostly exposed in scattered outcrops in the northern half of the state. Their discontinuous nature results from extensive Quaternary and Tertiary surficial cover, from Tertiary and Mesozoic granitic batholiths in western Sonora, and from widespread Tertiary volcanic deposits in the Sierra Madre Occidental in eastern Sonora. Cambrian and Ordovician shelf rocks were deposited as part of the the southern miogeocline on the southwestern continental margin of North America.

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...

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

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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

The southernmost record of a large erethizontid rodent (Hystricomorpha: Erethizontoidea) in the Pleistocene of South America: Biogeographic and paleoenvironmental implications

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Vezzosi, Raúl I.; Kerber, Leonardo

2018-03-01

The South American porcupines (Erethizontidae) are included in two genera: Chaetomys and Coendou. The latter is a very speciose taxon, with about 13 living species. During at least the late Pliocene-early Pleistocene, erethizontids immigrated to Central and North America during the Great American Biotic Interchange. Although some Pleistocene fossils have been reported, the Quaternary history of this clade is still understudied. The only known extinct species is Coendou magnus. In this work, a fossil of a porcupine is reported from an Upper Pleistocene fluvial sedimentary sequence cropping out in the Northern Pampa geomorphological region, Santa Fe Province, Argentina. Despite this group having different living forms widely distributed in South American Neotropical woodland habitats, the Pleistocene occurrences of Erethizontidae are scarce and limited to Upper Pleistocene deposits from Bolivia, Brazil, and Uruguay. Currently, the specimen here reported represents the only Pleistocene porcupine from Argentina with a stratigraphical context. The morphological characters as well as the dimensions indicate that it is close to the Pleistocene erethizontid Coendou magnus. In this context, the presence of this erethizontid in such a southern locality, together with other taxa recorded from this site and the associated geological and paleoenvironmental evidence, indicates subtropical conditions, compared with the current conditions, which may have allowed a southern displacement of taxa more related to woodlands and xeric subtropical environments.

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.)

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

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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.

Geographically Sourcing Cocaine’s Origin - Delineation of the Nineteen Major Coca Growing Regions in South America

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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.

Ocean transport and variability studies of the South Pacific, Southern, and Indian Oceans

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Church, John A.; Cresswell, G. R.; Nilsson, C. S.; Mcdougall, T. J.; Coleman, R.; Rizos, C.; Penrose, J.; Hunter, J. R.; Lynch, M. J.

1991-01-01

The objectives of this study are to analyze ocean dynamics in the western South Pacific and the adjacent Southern Ocean and the eastern Indian Ocean. Specifically, our objectives for these three regions are, for the South Pacific Ocean: (1) To estimate the volume transport of the east Australian Current (EAC) along the Australian coast and in the Tasman Front, and to estimate the time variability (on seasonal and interannual time scales) of this transport. (2) To contribute to estimating the meridional heat and freshwater fluxes (and their variability) at about 30 deg S. Good estimates of the transport in the western boundary current are essential for accurate estimates of these fluxes. (3) To determine how the EAC transport (and its extension, the Tasman Front and the East Auckland Current) closes the subtropical gyre of the South Pacific and to better determine the structure at the confluence of this current and the Antarctic Circumpolar Current. (4) To examine the structure and time variability of the circulation in the western South Pacific and the adjacent Southern Ocean, particularly at the Tasman Front. For the Indian Ocean: (5) To study the seasonal interannual variations in the strength of the Leeuwin Current. (6) To monitor the Pacific-Indian Ocean throughflow and the South Equatorial and the South Java Currents between northwest Australia and Indonesia. (7) To study the processes that form the water of the permanent oceanic thermocline and, in particular, the way in which new thermocline water enters the permanent thermocline in late winter and early spring as the mixed layer restratifies. For the Southern Ocean: (8) To study the mesoscale and meridional structure of the Southern Ocean between 150 deg E and 170 deg E; in particular, to describe the Antarctic frontal system south of Tasmania and determine its interannual variability; to estimate the exchanges of heat, salt, and other properties between the Indian and Pacific Oceans; and to investigate the

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.

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

Fossil history of the marsh rats of the genus Holochilus and Lundomys (Cricetidae, Sigmodontinae in southern South America

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Teta, P.

2011-06-01

Full Text Available The sister genera Holochilus and Lundomys, plus the extinct forms Carletonomys and Noronhomys and the living Pseudoryzomys, constitute a small clade of amphibious sigmodontine rodents that inhabits in tropical and subtropical environments of the Neotropics. Based on almost all the available fossil evidence recovered in Argentina, Bolivia, southeastern Brazil, and Uruguay we revised the paleontological record of Holochilus and Lundomys in southern South America. Past distributions and chronologies indicate the following occurrences [biochrons] for the study area: Holochilus brasiliensis (Middle Pleistocene-Recent in Argentina, Late Pleistocene-Recent in Brazil, H. chacarius (Late Holocene-Recent in Argentina, Early Holocene-Recent in Bolivia, †H. primigenius (Middle Pleistocene in Bolivia, and Lundomys molitor (Middle Pleistocene-Late Pleistocene in Argentina, Late Pleistocene-Recent in Uruguay. Taking into account the present distributions and environmental requirements of these rodents we hypothesize several expansion/retraction episodes of their populations triggered by the occurrence of moist/dry climatic pulses during Pleistocene-Holocene times.Los géneros hermanos Holochilus y Lundomys, junto con las formas extintas Carletonomys y Noronhomys y la viviente Pseudoryzomys, constituyen un pequeño clado de sigmodontinos de hábitos anfibios, que habitan en ambientes tropicales y subtropicales del Neotrópico. Basándonos en la totalidad de la evidencia fósil disponible para Argentina, Bolivia, sudeste de Brasil y Uruguay se revisó el registro paleontológico de Holochilus y Lundomys de la porción austral de América del Sur. Las distribuciones en el pasado y sus cronologías indican las siguientes ocurrencias para el área de estudio: Holochilus brasiliensis (Pleistoceno Medio-Reciente en Argentina, Pleistoceno Tardío-Reciente en Brasil, H. chacarius (Holoceno Tardío-Reciente en Argentina, Holoceno Temprano-Reciente en Bolivia, �

Detection and follow-up of chronic obstructive pulmonary disease (COPD and risk factors in the Southern Cone of Latin America. the pulmonary risk in South America (PRISA study

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Olivera Héctor

2011-06-01

Full Text Available Abstract Background The World Health Organization has estimated that by 2030, chronic obstructive pulmonary disease will be the third leading cause of death worldwide. Most knowledge of chronic obstructive pulmonary disease is based on studies performed in Europe or North America and little is known about the prevalence, patient characteristics and change in lung function over time in patients in developing countries, such as those of Latin America. This lack of knowledge is in sharp contrast to the high levels of tobacco consumption and exposure to biomass fuels exhibited in Latin America, both major risk factors for the development of chronic obstructive pulmonary disease. Studies have also demonstrated that most Latin American physicians frequently do not follow international chronic obstructive pulmonary disease diagnostic and treatment guidelines. The PRISA Study will expand the current knowledge regarding chronic obstructive pulmonary disease and risk factors in Argentina, Chile and Uruguay to inform policy makers and health professionals on the best policies and practices to address this condition. Methods/Design PRISA is an observational, prospective cohort study with at least four years of follow-up. In the first year, PRISA has employed a randomized three-staged stratified cluster sampling strategy to identify 6,000 subjects from Marcos Paz and Bariloche, Argentina, Temuco, Chile, and Canelones, Uruguay. Information, such as comorbidities, socioeconomic status and tobacco and biomass exposure, will be collected and spirometry, anthropometric measurements, blood sampling and electrocardiogram will be performed. In year four, subjects will have repeat measurements taken. Discussion There is no longitudinal data on chronic obstructive pulmonary disease incidence and risk factors in the southern cone of Latin America, therefore this population-based prospective cohort study will fill knowledge gaps in the prevalence and incidence of

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

Land Cover Characterization and Mapping of South America for the Year 2010 Using Landsat 30 m Satellite Data

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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.

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.

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

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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.

Ancient mitochondrial DNA reveals convergent evolution of giant short-faced bears (Tremarctinae) in North and South America.

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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).

Supplement of: The Influence of Volcanic Eruptions on the Climate of Tropical South America During the Last Millennium in an Isotope-Enabled General Circulation Model

Science.gov (United States)

Colose, Christopher; LeGrande, Allegra N.; Vuille, Mathias

2016-01-01

Currently, little is known on how volcanic eruptions impact large-scale climate phenomena such as South American paleo-intertropical Convergence Zone (ITCZ) position and summer monsoon behavior. In this paper, an analysis of observations and model simulations is employed to assess the influence of large volcanic eruptions on the climate of tropical South America. This problem is first considered for historically recent volcanic episodes for which more observations are available but where fewer events exist and the confounding effects of El NioSouthern Oscillation (ENSO) lead to inconclusive interpretation of the impact of volcanic eruptions at the continental scale. Therefore, we also examine a greater number of reconstructed volcanic events for the period 850CE to present that are incorporated into the NASA GISS ModelE2-R simulation of the last millennium.An advantage of this model is its ability to explicitly track water isotopologues throughout the hydrologic cycle and simulating the isotopic imprint following a large eruption. This effectively removes a degree of uncertainty associated with error-prone conversion of isotopic signals into climate variables, and allows for a direct comparison between GISS simulations and paleoclimate proxy records.Our analysis reveals that both precipitation and oxygen isotope variability respond with a distinct seasonal and spatial structure across tropical South America following an eruption. During austral winter, the heavy oxygen isotope in precipitation is enriched, likely due to reduced moisture convergence in the ITCZ domain and reduced rainfall over northern South America. During austral summer, however, more negative values of the precipitation isotopic composition are simulated over Amazonia, despite reductions in rainfall, suggesting that the isotopic response is not a simple function of the amount effect. During the South American monsoon season, the amplitude of the temperature response to volcanic forcing is larger

Status and challenges for conservation of small mammal assemblages in South America.

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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

Dynamics of the Water Circulations in the Southern South China Sea and Its Seasonal Transports.

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Daryabor, Farshid; Ooi, See Hai; Samah, Azizan Abu; Akbari, Abolghasem

2016-01-01

A three-dimensional Regional Ocean Modeling System is used to study the seasonal water circulations and transports of the Southern South China Sea. The simulated seasonal water circulations and estimated transports show consistency with observations, e.g., satellite altimeter data set and re-analysis data of the Simple Ocean Data Assimilation. It is found that the seasonal water circulations are mainly driven by the monsoonal wind stress and influenced by the water outflow/inflow and associated currents of the entire South China Sea. The intrusion of the strong current along the East Coast of Peninsular Malaysia and the eddies at different depths in all seasons are due to the conservation of the potential vorticity as the depth increases. Results show that the water circulation patterns in the northern part of the East Coast of Peninsular Malaysia are generally dominated by the geostrophic currents while those in the southern areas are due solely to the wind stress because of negligible Coriolis force there. This study clearly shows that individual surface freshwater flux (evaporation minus precipitation) controls the sea salinity balance in the Southern South China Sea thermohaline circulations. Analysis of climatological data from a high resolution Regional Ocean Modeling System reveals that the complex bathymetry is important not only for water exchange through the Southern South China Sea but also in regulating various transports across the main passages in the Southern South China Sea, namely the Sunda Shelf and the Strait of Malacca. Apart from the above, in comparision with the dynamics of the Sunda Shelf, the Strait of Malacca reflects an equally significant role in the annual transports into the Andaman Sea.

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

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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.

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

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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.

Redescription of some South American species of Belonuchus (Coleoptera: Staphylinidae, with a checklist of the southern South American species of the genus Redescripción de algunas especies sudamericanas de Belonuchus (Coleoptera: Staphylinidae, con una lista de las especies del género del sur de América del Sur

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Mariana Chani-Posse

2011-12-01

Full Text Available Six species of Belonuchus Nordmann, 1837 from South America are redescribed and illustrated: B. aluticollis (Bernhauer, 1921, B. castaneus Chani-Posse, 2006, B. flavicoxis (Bernhauer, 1912, B. multipunctatus (Coiffait, 1981, B. richteri (Bernhauer, 1912 and B. weiserianus (Bernhauer, 1921. A checklist of the 23 species of Belonuchus currently known from southern South America is appended. A lectotype is designated for B. richteri Bernhauer, 1922.Seis especies de Belonuchus Nordmann, 1837, de América del Sur se redescriben e ilustran: B. aluticollis (Bernhauer, 1921, B. castaneus Chani-Posse 2006, B. flavicoxis (Bernhauer, 1912, B. multipunctatus (Coiffait, 1981, B. richteri (Bernhauer, 1912 y B. weiserianus (Bernhauer, 1921. Se provee una lista de las 23 especies actualmente conocidas del sur de América del Sur. Se designa el lectotipo de B. richteri Bernhauer, 1922.

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

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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.

Xylella fastidiosa CoDiRO strain associated with the olive quick decline syndrome in southern Italy belongs to a clonal complex of the subspecies pauca that evolved in Central America.

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Marcelletti, Simone; Scortichini, Marco

2016-12-01

Xylella fastidiosa, a xylem-limited bacterium transmitted by xylem-fluid-feeding Hemiptera insects, causes economic losses of both woody and herbaceous plant species. A Xyl. fastidiosa subsp. pauca strain, namely CoDiRO, was recently found to be associated with the 'olive quick decline syndrome' in southern Italy (i.e. Apulia region). Recently, some Xyl. fastidiosa strains intercepted in France from Coffea spp. plant cuttings imported from Central and South America were characterized. The introduction of infected plant material from Central America in Apulia was also postulated even though an ad hoc study to confirm this hypothesis is lacking. In the present study, we assessed the complete and draft genome of 27 Xyl. fastidiosa strains. Through a genome-wide approach, we confirmed the occurrence of three subspecies within Xyl. fastidiosa, namely fastidiosa, multiplex and pauca, and demonstrated the occurrence of a genetic clonal complex of four Xyl. fastidiosa strains belonging to subspecies pauca which evolved in Central America. The CoDiRO strain displayed 13 SNPs when compared with a strain isolated in Costa Rica from Coffea sp. and 32 SNPs when compared with two strains obtained from Nerium oleander in Costa Rica. These results support the close relationships of the two strains. The four strains in the clonal complex contain prophage-like genes in their genomes. This study strongly supports the possibility of the introduction of Xyl. fastidiosa in southern Italy via coffee plants grown in Central America. The data also stress how the current global circulation of agricultural commodities potentially threatens the agrosystems worldwide.

Mortality in patients with HIV-1 infection starting antiretroviral therapy in South Africa, Europe, or North America: a collaborative analysis of prospective studies.

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Andrew Boulle

2014-09-01

Full Text Available High early mortality in patients with HIV-1 starting antiretroviral therapy (ART in sub-Saharan Africa, compared to Europe and North America, is well documented. Longer-term comparisons between settings have been limited by poor ascertainment of mortality in high burden African settings. This study aimed to compare mortality up to four years on ART between South Africa, Europe, and North America.Data from four South African cohorts in which patients lost to follow-up (LTF could be linked to the national population register to determine vital status were combined with data from Europe and North America. Cumulative mortality, crude and adjusted (for characteristics at ART initiation mortality rate ratios (relative to South Africa, and predicted mortality rates were described by region at 0-3, 3-6, 6-12, 12-24, and 24-48 months on ART for the period 2001-2010. Of the adults included (30,467 [South Africa], 29,727 [Europe], and 7,160 [North America], 20,306 (67%, 9,961 (34%, and 824 (12% were women. Patients began treatment with markedly more advanced disease in South Africa (median CD4 count 102, 213, and 172 cells/µl in South Africa, Europe, and North America, respectively. High early mortality after starting ART in South Africa occurred mainly in patients starting ART with CD4 count <50 cells/µl. Cumulative mortality at 4 years was 16.6%, 4.7%, and 15.3% in South Africa, Europe, and North America, respectively. Mortality was initially much lower in Europe and North America than South Africa, but the differences were reduced or reversed (North America at longer durations on ART (adjusted rate ratios 0.46, 95% CI 0.37-0.58, and 1.62, 95% CI 1.27-2.05 between 24 and 48 months on ART comparing Europe and North America to South Africa. While bias due to under-ascertainment of mortality was minimised through death registry linkage, residual bias could still be present due to differing approaches to and frequency of linkage.After accounting for under

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

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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

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

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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 ...

Multiple sclerosis in South America: month of birth in different latitudes does not seem to interfere with the prevalence or progression of the disease

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Yara Dadalti Fragoso

2013-09-01

Full Text Available Objective To assess whether the month of birth in different latitudes of South America might influence the presence or severity of multiple sclerosis (MS later in life. Methods Neurologists in four South American countries working at MS units collected data on their patients' month of birth, gender, age, and disease progression. Results Analysis of data from 1207 MS patients and 1207 control subjects did not show any significant variation in the month of birth regarding the prevalence of MS in four latitude bands (0–10; 11–20; 21–30; and 31–40 degrees. There was no relationship between the month of birth and the severity of disease in each latitude band. Conclusion The results from this study show that MS patients born to mothers who were pregnant at different Southern latitudes do not follow the seasonal pattern observed at high Northern latitudes.

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.

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

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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.

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

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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.

Origin of samples of Cannabis sativa through insect fragments associated with compacted hemp drug in South America

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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.

Mortality in Patients with HIV-1 Infection Starting Antiretroviral Therapy in South Africa, Europe, or North America: A Collaborative Analysis of Prospective Studies

Science.gov (United States)

Boulle, Andrew; Schomaker, Michael; May, Margaret T.; Hogg, Robert S.; Shepherd, Bryan E.; Monge, Susana; Keiser, Olivia; Lampe, Fiona C.; Giddy, Janet; Ndirangu, James; Garone, Daniela; Fox, Matthew; Ingle, Suzanne M.; Reiss, Peter; Dabis, Francois; Costagliola, Dominique; Castagna, Antonella; Ehren, Kathrin; Campbell, Colin; Gill, M. John; Saag, Michael; Justice, Amy C.; Guest, Jodie; Crane, Heidi M.; Egger, Matthias; Sterne, Jonathan A. C.

2014-01-01

Background High early mortality in patients with HIV-1 starting antiretroviral therapy (ART) in sub-Saharan Africa, compared to Europe and North America, is well documented. Longer-term comparisons between settings have been limited by poor ascertainment of mortality in high burden African settings. This study aimed to compare mortality up to four years on ART between South Africa, Europe, and North America. Methods and Findings Data from four South African cohorts in which patients lost to follow-up (LTF) could be linked to the national population register to determine vital status were combined with data from Europe and North America. Cumulative mortality, crude and adjusted (for characteristics at ART initiation) mortality rate ratios (relative to South Africa), and predicted mortality rates were described by region at 0–3, 3–6, 6–12, 12–24, and 24–48 months on ART for the period 2001–2010. Of the adults included (30,467 [South Africa], 29,727 [Europe], and 7,160 [North America]), 20,306 (67%), 9,961 (34%), and 824 (12%) were women. Patients began treatment with markedly more advanced disease in South Africa (median CD4 count 102, 213, and 172 cells/µl in South Africa, Europe, and North America, respectively). High early mortality after starting ART in South Africa occurred mainly in patients starting ART with CD4 count Africa, Europe, and North America, respectively. Mortality was initially much lower in Europe and North America than South Africa, but the differences were reduced or reversed (North America) at longer durations on ART (adjusted rate ratios 0.46, 95% CI 0.37–0.58, and 1.62, 95% CI 1.27–2.05 between 24 and 48 months on ART comparing Europe and North America to South Africa). While bias due to under-ascertainment of mortality was minimised through death registry linkage, residual bias could still be present due to differing approaches to and frequency of linkage. Conclusions After accounting for under-ascertainment of mortality

Southern promises: a snapshot of the microbiology research landscape in South America based on bibliometric data.

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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.

War, religion, and white supremacy in comparative perspective: South Africa and the American South

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R M�ller

2004-10-01

Full Text Available The southern states of the United States of America and South Africa share a number of analogous historical realities. One of these, which is the main subject of� this article,� is� the way in which the memory of a lost war had fused cultural mythology and religious symbolism to provide a foundation for the formation and maintenance of attitudes of white supremacy in both contexts.� This article seeks to achieve a historical� understanding of the complex interrelationship between the development of cultural identity and Protestant Christianity by� focusing on these issues in the histories of the Afrikaner and the white American Southerner in comparative perspective.�

South American natural gas trade: the road ahead

International Nuclear Information System (INIS)

Reinsch, A.E.; Tissot, R.; Peacey, D.

1997-01-01

The current state and future prospects for the natural gas sector in South America were examined, including the ability of the natural gas resource base to meet potential gas demand in the Southern Cone region (Argentina, Bolivia, Brazil, Chile, Paraguay, Peru and Uruguay). The physical, legal, fiscal, regulatory and political developments in the hydrocarbon-producing countries in the Southern Cone region were reviewed. For example, in Colombia, the domestic gas market potential and resource base argue in favor of a closed domestic gas sector development policy. In contrast, Venezuela, a country that already has a well developed domestic gas sector, is pursuing offshore market development through both petrochemical and liquefied natural gas initiatives. Following a comprehensive description of individual gas resources, markets and market potential, and legal, institutional and political environments, the study reports on a number of alternative scenarios concerning natural gas integration in the Southern Cone region, developed by using the South America Natural Gas (SANG) model. The following scenarios were reviewed: (1) closure and confinement, (2) integration and expansion, and (3) gains from technology. It was estimated that potential gas demand in the Southern Cone region is projected to grow from 900 billion cubic feet per year in 1994 to over 5.3 trillion cubic feet in 2021. The majority of growth is expected in Brazil. The overall conclusion of the study was that regardless of the scenario, Southern Core gas sector integration has strong economic and commercial merit, and that the natural gas resource base in the Southern Cone, as represented by the gas reserves database, is more than adequate to service potential demand. 100 refs., 50 tabs., 54 figs

The Southern Ocean and South Pacific Region

OpenAIRE

Kelleher, K.; Warnau, Michel; Failler, Pierre; Pecl, Gretta; Turley, Carol; Boeuf, Gilles; Laffoley, Dan; Parker, Laura; Gurney, Leigh

2012-01-01

The Region comprises three sub-regions (FAO Statistical Areas) with very different characteristics. The South Pacific includes the vast and virtually unpopulated Southern Ocean surrounding the Antarctic. It has the world’s largest fisheries off Peru and Chile and some of the world’s best managed fisheries in Australia and New Zealand. The Region has over 27% of the world’s ocean area and over 98% of the Region’s total area of 91 million km2 is ‘open ocean’. The Region contains less than 5% of...

Subduction and Plate Edge Tectonics in the Southern Caribbean

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Levander, A.; Schmitz, M.; Niu, F.; Bezada, M. J.; Miller, M. S.; Masy, J.; Ave Lallemant, H. G.; Pindell, J. L.; Bolivar Working Group

2013-05-01

The southern Caribbean plate boundary consists of a subduction zone at at either end of a complex strike-slip fault system: In the east at the Lesser Antilles subduction zone, the Atlantic part of the South American plate subducts beneath the Caribbean. In the north and west in the Colombia basin, the Caribbean subducts under South America. In a manner of speaking, the two plates subduct beneath each other. Finite-frequency teleseismic P-wave tomography confirms this, imaging the Atlantic and the Caribbean plates subducting steeply in opposite directions to transition zone depths under northern South America (Bezada et al, 2010). The two subduction zones are connected by the El Pilar-San Sebastian strike-slip fault system, a San Andreas scale system that has been cut off at the Bocono fault, the southeastern boundary fault of the Maracaibo block. A variety of seismic probes identify subduction features at either end of the system (Niu et al, 2007; Clark et al., 2008; Miller et al. 2009; Growdon et al., 2009; Huang et al., 2010; Masy et al, 2011). The El Pilar system forms at the southeastern corner of the Antilles subduction zone with the Atlantic plate tearing from South America. The deforming plate edges control mountain building and basin formation at the eastern end of the strike-slip system. Tearing the Atlantic plate from the rest of South America appears to cause further lithospheric instability continentward. In northwestern South America the Caribbean plate very likely also tears, as its southernmost element subducts at shallow angles under northernmost Colombia but then rapidly descends to the transition zone under Lake Maracaibo (Bezada et al., 2010). We believe that the flat slab controls the tectonics of the Neogene Merida Andes, Perija, and Santa Marta ranges. The nonsubducting part of the Caribbean plate also underthrusts northern Venezuela to about the width of the coastal mountains (Miller et al., 2009). We infer that the edge of the underthrust

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.)

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.

Future change of climate in South America in the late twenty-first century: intercomparison of scenarios from three regional climate models

Science.gov (United States)

Marengo, Jose A.; Ambrizzi, Tercio; Da Rocha, Rosmeri P.; Alves, Lincoln M.; Cuadra, Santiago V.; Valverde, Maria C.; Torres, Roger R.; Santos, Daniel C.; Ferraz, Simone E. T.

2010-11-01

Regional climate change projections for the last half of the twenty-first century have been produced for South America, as part of the CREAS (Cenarios REgionalizados de Clima Futuro da America do Sul) regional project. Three regional climate models RCMs (Eta CCS, RegCM3 and HadRM3P) were nested within the HadAM3P global model. The simulations cover a 30-year period representing present climate (1961-1990) and projections for the IPCC A2 high emission scenario for 2071-2100. The focus was on the changes in the mean circulation and surface variables, in particular, surface air temperature and precipitation. There is a consistent pattern of changes in circulation, rainfall and temperatures as depicted by the three models. The HadRM3P shows intensification and a more southward position of the subtropical Pacific high, while a pattern of intensification/weakening during summer/winter is projected by the Eta CCS/RegCM3. There is a tendency for a weakening of the subtropical westerly jet from the Eta CCS and HadRM3P, consistent with other studies. There are indications that regions such of Northeast Brazil and central-eastern and southern Amazonia may experience rainfall deficiency in the future, while the Northwest coast of Peru-Ecuador and northern Argentina may experience rainfall excesses in a warmer future, and these changes may vary with the seasons. The three models show warming in the A2 scenario stronger in the tropical region, especially in the 5°N-15°S band, both in summer and especially in winter, reaching up to 6-8°C warmer than in the present. In southern South America, the warming in summer varies between 2 and 4°C and in winter between 3 and 5°C in the same region from the 3 models. These changes are consistent with changes in low level circulation from the models, and they are comparable with changes in rainfall and temperature extremes reported elsewhere. In summary, some aspects of projected future climate change are quite robust across this set of

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

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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.

First case of New Delhi metallo-β-lactamase in Klebsiella pneumoniae from Ecuador: An update for South America

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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

The meteorological environment of the tropospheric ozone maximum over the tropical South Atlantic

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Krishnamurti, T N; Fuelberg, H E; Bensman, E L; Sinha, M C; Oosterhof, D; Kumar, V B [Florida State University, Tallahassee, FL (United States). Department of Meteorology

1993-01-01

This paper examines atmospheric flow patterns over the Southern Atlantic Ocean, where a maximum of tropospheric ozone is observed just west of Southern Africa. The climatology of the South Atlantic basin is shown to favour flow off from South America and Africa converging into the area of high tropospheric ozone. This ozone is initially attributable to byproducts of biomass burning over both these continents. A case study, carried out over 6 days during October 1989, was used to determine the effect of a purely advective scheme (no photochemistry) on the distribution of ozone over the basin. The results showed a pattern in which ozone accumulated off the west coast of South Africa within 72 hours after beginning with an homogenous, zonally-symmetric distribution of ozone. 11 refs.

The foot and mouth disease network in the southern cone of South America: an example of regional governance.

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Corrales Irrazábal, H A

2012-08-01

The fact that foot and mouth disease is highly contagious, easily spread and of major commercial importance makes it a redoubtable challenge for animal health in South American countries and the world over. A number of factors impact directly on the effectiveness of national programmes to eradicate foot and mouth disease. Therefore, in order to meet the challenges posed by today's globalised world, it is of the utmost importance that national level eradication programmes be considered state policies and that they be the subject of broad political agreement at the highest level and consolidated as regional programmes between national Veterinary Services. The programmes, agreements and technical cooperation projects established jointly by Member Countries of the Southern Common Market (MERCOSUR) were a key factor in building management capacity to control foot and mouth disease in the area. Another key factor has been a partnership with one of the most sensitive sectors--the private production sector. Its active and responsible participation in operational functions has done much to strengthen and ensure the competitive development of South American countries and consolidate their role as global beef exporters. However, to prevent further outbreaks it is essential to maintain and reinforce the structure of national programmes and to have strong and highly trained Veterinary Services and sufficient funding to ensure efficient and sustainable plans. These plans must enable Veterinary Services, by means of good governance, to implement effective measures in the areas of animal health and international trade in animals and animal products/by-products, thereby achieving rapid and more equitable social and economic development.

Avian Influenza Virus Isolated in Wild Waterfowl in Argentina: Evidence of a potentially unique phylogenetic lineage in South America

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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

Sociology with a Southern Face: Why Are We Sociologists and What Are We Doing about It in the South?

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Wimberley, Ronald C.

2008-01-01

Sociology with a Southern face characterizes Southern sociologists and Southern social issues. This article asks why we are sociologists and what we are doing about it in the South. I posit that many Southern sociologists share common biographical experiences that provide insights for understanding and solving Southern problems. Longstanding…

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

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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

Spatial and temporal uplift history of South America from calibrated drainage analysis

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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.

Transnational entrepreneurship in the Global South: evidence from Southern Africa

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Rogerson Jayne M.

2015-12-01

Full Text Available Transnational entrepreneurship is an evolving field of research which occupies an interface between social and regional sciences. The phenomenon of transnational entrepreneurship is driven by entrepreneurs that migrate from one country to another whilst maintaining business-related linkages with their former country of origin and the adopted country. The most critical distinguishing feature of transnational entrepreneurs is bifocality or the ability to function across two different business environments. Most writings on transnational entrepreneurship concentrate on business individuals from the global South operating enterprises in the global North. Absent are empirical studies of the nature and behaviour of transnational migrant entrepreneurs who operate across or between emerging or developing economies. This South-South gap in international research concerning transnational entrepreneurship is addressed in the paper which provides an exploratory analysis of the nature of transnational entrepreneurship occurring in Southern Africa using evidence of Zimbabwean transnational entrepreneurs based in Johannesburg, South Africa.

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

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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.

Comparison of modern pollen distribution between the northern and southern parts of the South China Sea.

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Luo, Chuanxiu; Chen, Muhong; Xiang, Rong; Liu, Jianguo; Zhang, Lanlan; Lu, Jun

2015-04-01

The authors conducted a palynological analysis based on different number of air pollen samples for the northern and southern parts of the South China Sea, respectively, in order to give a reference to reconstruct the paleoclimate of the area. (1) Fifteen air pollen samples were collected from the northern part of the South China Sea from August to September 2011, and 13 air pollen samples were collected from the southern part of the South China Sea in December 2011. The pollen types were more abundant in the north than in the south. The total pollen number and concentration in the north was 10 times more than that in the south, which may be because of the sampling season. Airborne pollen types and concentrations have a close relationship with wind direction and distance from the sampling point to the continent. (2) Seventy-four samples were collected from surface sediments in the northern part of the South China Sea in the autumn. Thirty-three samples were collected from surface sediments in the southern part of the South China Sea in the winter. Pollen concentrations in the north were nearly 10 times higher than that in the south. This is because trilete spores are transported by rivers from Hainan Island to the sea and also by the summer monsoon-forced marine current. (3) Ten air pollen samples and 10 surface sediments samples were selected for comparison. The pollen and spores in the air were mainly herbaceous and woody pollen, excluding fern spores, having seasonal pollen characteristics. Pollen in the surface sediments were mainly trilete, Pinus, and herbaceous, and may also show a combination of annual pollen characteristics.

Diversity and distribution patterns in high southern latitude sponges.

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Rachel V Downey

Full Text Available Sponges play a key role in Antarctic marine benthic community structure and dynamics and are often a dominant component of many Southern Ocean benthic communities. Understanding the drivers of sponge distribution in Antarctica enables us to understand many of general benthic biodiversity patterns in the region. The sponges of the Antarctic and neighbouring oceanographic regions were assessed for species richness and biogeographic patterns using over 8,800 distribution records. Species-rich regions include the Antarctic Peninsula, South Shetland Islands, South Georgia, Eastern Weddell Sea, Kerguelen Plateau, Falkland Islands and north New Zealand. Sampling intensity varied greatly within the study area, with sampling hotspots found at the Antarctic Peninsula, South Georgia, north New Zealand and Tierra del Fuego, with limited sampling in the Bellingshausen and Amundsen seas in the Southern Ocean. In contrast to previous studies we found that eurybathy and circumpolar distributions are important but not dominant characteristics in Antarctic sponges. Overall Antarctic sponge species endemism is ∼43%, with a higher level for the class Hexactinellida (68%. Endemism levels are lower than previous estimates, but still indicate the importance of the Polar Front in isolating the Southern Ocean fauna. Nineteen distinct sponge distribution patterns were found, ranging from regional endemics to cosmopolitan species. A single, distinct Antarctic demosponge fauna is found to encompass all areas within the Polar Front, and the sub-Antarctic regions of the Kerguelen Plateau and Macquarie Island. Biogeographical analyses indicate stronger faunal links between Antarctica and South America, with little evidence of links between Antarctica and South Africa, Southern Australia or New Zealand. We conclude that the biogeographic and species distribution patterns observed are largely driven by the Antarctic Circumpolar Current and the timing of past continent

Lithium Geopolitics in South America and the divergents national public policies

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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.

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)

Geographical distribution of the association between El Niño South Oscillation and dengue fever in the Americas: a continental analysis using geographical information system-based techniques

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Marcos C. Ferreira

2014-11-01

Full Text Available El Niño South Oscillation (ENSO is one climatic phenomenon related to the inter-annual variability of global meteorological patterns influencing sea surface temperature and rainfall variability. It influences human health indirectly through extreme temperature and moisture conditions that may accelerate the spread of some vector-borne viral diseases, like dengue fever (DF. This work examines the spatial distribution of association between ENSO and DF in the countries of the Americas during 1995-2004, which includes the 1997-1998 El Niño, one of the most important climatic events of 20th century. Data regarding the South Oscillation index (SOI, indicating El Niño-La Niña activity, were obtained from Australian Bureau of Meteorology. The annual DF incidence (AIy by country was computed using Pan-American Health Association data. SOI and AIy values were standardised as deviations from the mean and plotted in bars-line graphics. The regression coefficient values between SOI and AIy (rSOI,AI were calculated and spatially interpolated by an inverse distance weighted algorithm. The results indicate that among the five years registering high number of cases (1998, 2002, 2001, 2003 and 1997, four had El Niño activity. In the southern hemisphere, the annual spatial weighted mean centre of epidemics moved southward, from 6° 31' S in 1995 to 21° 12' S in 1999 and the rSOI,AI values were negative in Cuba, Belize, Guyana and Costa Rica, indicating a synchrony between higher DF incidence rates and a higher El Niño activity. The rSOI,AI map allows visualisation of a graded surface with higher values of ENSO-DF associations for Mexico, Central America, northern Caribbean islands and the extreme north-northwest of South America.

Seismic hazard, risk, and design for South America

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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

Feline immunodeficiency virus in South America.

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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.

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

Effects of Atlantic warm pool variability over climate of South America tropical transition zone

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Ricaurte Villota, Constanza; Romero-Rodríguez, Deisy; Andrés Ordoñez-Zuñiga, Silvio; Murcia-Riaño, Magnolia; Coca-Domínguez, Oswaldo

2016-04-01

Colombia is located in the northwestern corner of South America in a climatically complex region due to the influence processes modulators of climate both the Pacific and Atlantic region, becoming in a transition zone between phenomena of northern and southern hemisphere. Variations in the climatic conditions of this region, especially rainfall, have been attributed to the influence of the El Nino Southern Oscillation (ENSO), but little is known about the interaction within Atlantic Ocean and specifically Caribbean Sea with the environmental conditions of this region. In this work We studied the influence of the Atlantic Warm Pool (AWP) on the Colombian Caribbean (CC) climate using data of Sea Surface Temperature (SST) between 1900 - 2014 from ERSST V4, compared with in situ data SIMAC (National System for Coral Reef Monitoring in Colombia - INVEMAR), rainfall between 1953-2013 of meteorological stations located at main airports in the Colombian Caribbean zone, administered by IDEAM, and winds data between 2003 - 2014 from WindSat sensor. The parameters analyzed showed spatial differences throughout the study area. SST anomalies, representing the variability of the AWP, showed to be associated with Multidecadal Atlantic Oscillation (AMO) and with the index of sea surface temperature of the North-tropical Atlantic (NTA), the variations was on 3 to 5 years on the ENSO scale and of approximately 11 years possibly related to solar cycles. Rainfall anomalies in the central and northern CC respond to changes in SST, while in the south zone these are not fully engage and show a high relationship with the ENSO. Finally, the winds also respond to changes in SST and showed a signal approximately 90 days possibly related to the Madden-Julian Oscillation, whose intensity depends on the CC region being analyzed. The results confirm that region is a transition zone in which operate several forcing, the variability of climate conditions is difficult to attribute only one, as ENSO

LEONA: Transient Luminous Event and Thunderstorm High Energy Emission Collaborative Network in Latin America

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Sao Sabbas, F. T.

2012-12-01

This project has the goal of establishing the Collaborative Network LEONA, to study the electrodynamical coupling of the atmospheric layers signaled by Transient Luminous Events - TLEs and high energy emissions from thunderstorms. We will develop and install a remotely controlled network of cameras to perform TLE observations in different locations in South America and one neutron detector in southern Brazil. The camera network will allow building a continuous data set of the phenomena studied in this continent. The first two trial units of the camera network are already installed, in Brazil and Peru, and two more will be installed until December 2012, in Argentina and Brazil. We expect to determine the TLE geographic distribution, occurrence rate, morphology, and possible coupling with other geophysical phenomena in South America, such as the South Atlantic Magnetic Anomaly - SAMA. We also expect to study thunderstorm neutron emissions in a region of intense electrical activity, measuring neutron fluxes with high time resolution simultaneously with TLEs and lightning for the first time in South America. Using an intensified high-speed camera for TLE observation during 2 campaigns we expect to be able to determine the duration and spatial- temporal development of the TLEs observed, to study the structure and initiation of sprites and to measure the velocity of development of sprite structures and the sprite delay. The camera was acquired via the FAPESP project DEELUMINOS (2005-2010), which also nucleated our research group Atmospheric Electrodynamical Coupling - ACATMOS. LEONA will nucleate this research in other institutions in Brazil and other countries in South America, providing continuity for this important research in our region. The camera network will be an unique tool to perform consistent long term TLE observation, and in fact is the only way to accumulate a data set for a climatological study of South America, since satellite instrumentation turns off in

Energy integration experiences at the Europe, at the Nordic countries and at the Central America: considerations relevant to the South America integration process; Experiencias de integracao energetica na Europa, nos paises nordicos e na America Central: consideracoes relevantes ao processo de integracao Sul-Americana

Energy Technology Data Exchange (ETDEWEB)

Campos, Adriana Fiorotti; Andreza, Fernanda Marques Pereira; Soares, Jeferson Borghetti; Pinheiro, Maria Fernanda Bacile; Oliveira, Ricardo Gorini de [Empresa de Pesquisa Energetica (EPE), Rio de Janeiro, RJ (Brazil)], Emails: adriana.campos@epe.gov.br, fernanda.andreza@epe.gov.br; jeferson.soares@epe.gov.br, maria.pinheiro, ricardo.gorini@epe.gov.br

2010-07-01

In view of institutional/contractual regulatory problems at the South America, some experiences of energy integration at the electrical sectors and natural gas (Nordic countries. European Union and Central America), identifying related vantages and advantageous. Besides, there is an attempt of characterization of the process step of energy integration, and the fitting of regions in these steps, observing that the process of energy integration in the South America it is found in a initial step yet if it is considered the used methodology by the Colombian enterprise Interconexion Electrica S.A.E.S.P. - ISA (2007)

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.)

The impact of the subtropical South Atlantic SST on South American precipitation

Directory of Open Access Journals (Sweden)

A. S. Taschetto

2008-11-01

Full Text Available The Community Climate Model (CCM3 from the National Center for Atmospheric Research (NCAR is used to investigate the effect of the South Atlantic sea surface temperature (SST anomalies on interannual to decadal variability of South American precipitation. Two ensembles composed of multidecadal simulations forced with monthly SST data from the Hadley Centre for the period 1949 to 2001 are analysed.

A statistical treatment based on signal-to-noise ratio and Empirical Orthogonal Functions (EOF is applied to the ensembles in order to reduce the internal variability among the integrations. The ensemble treatment shows a spatial and temporal dependence of reproducibility. High degree of reproducibility is found in the tropics while the extratropics is apparently less reproducible. Austral autumn (MAM and spring (SON precipitation appears to be more reproducible over the South America-South Atlantic region than the summer (DJF and winter (JJA rainfall. While the Inter-tropical Convergence Zone (ITCZ region is dominated by external variance, the South Atlantic Convergence Zone (SACZ over South America is predominantly determined by internal variance, which makes it a difficult phenomenon to predict. Alternatively, the SACZ over western South Atlantic appears to be more sensitive to the subtropical SST anomalies than over the continent.

An attempt is made to separate the atmospheric response forced by the South Atlantic SST anomalies from that associated with the El Niño – Southern Oscillation (ENSO. Results show that both the South Atlantic and Pacific SSTs modulate the intensity and position of the SACZ during DJF. Particularly, the subtropical South Atlantic SSTs are more important than ENSO in determining the position of the SACZ over the southeast Brazilian coast during DJF. On the other hand, the ENSO signal seems to influence the intensity of the SACZ not only in DJF but especially its oceanic branch during MAM. Both local and

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.

First records of Casiornis rufus (Vieillot, 1816) (Aves, Tyrannidae) for the state of Rio Grande do Sul, southern Brazil

DEFF Research Database (Denmark)

Vizentin-Bugoni, Jeferson; Bellagamba-Oliveira, Danielle; Bellagamba, Gina

2015-01-01

The Rufous Casiornis, Casiornis rufus (Vielliot, 1916), is widespread in central South America, reaching its southernmost distribution in northern Argentina and Uruguay. Here we present the first nine records of the species for Rio Grande do Sul state, southern Brazil. The records were documented...

The youngest South American rhynchocephalian, a survivor of the K/Pg extinction.

Science.gov (United States)

Apesteguía, Sebastián; Gómez, Raúl O; Rougier, Guillermo W

2014-10-07

Rhynchocephalian lepidosaurs, though once widespread worldwide, are represented today only by the tuatara (Sphenodon) of New Zealand. After their apparent early Cretaceous extinction in Laurasia, they survived in southern continents. In South America, they are represented by different lineages of Late Cretaceous eupropalinal forms until their disappearance by the Cretaceous/Palaeogene (K/Pg) boundary. We describe here the only unambiguous Palaeogene rhynchocephalian from South America; this new taxon is a younger species of the otherwise Late Cretaceous genus Kawasphenodon. Phylogenetic analysis confirms the allocation of the genus to the clade Opisthodontia. The new form from the Palaeogene of Central Patagonia is much smaller than Kawasphenodon expectatus from the Late Cretaceous of Northern Patagonia. The new species shows that at least one group of rhynchocephalians not related to the extant Sphenodon survived in South America beyond the K/Pg extinction event. Furthermore, it adds to other trans-K/Pg ectotherm tetrapod taxa, suggesting that the end-Cretaceous extinction affected Patagonia more benignly than the Laurasian landmasses. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

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…

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.

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,...

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...

Agro-fuels: southern impacts

International Nuclear Information System (INIS)

Duterme, B.

2011-01-01

At a time of controversies about global warming, agro-fuels production is often presented as a future solution for automotive fuels and as a new way of development for southern countries. However, in Asia, South America and Africa, it very often takes the form of huge mono-culture areas of sugar cane, palm oil and soy bean in the hands of multinational companies of the agriculture and food industry. The consequences of these land, social and environmental impacts in Southern countries is an increase of disequilibria and a threat for the diet of local populations by changing the appropriation of lands. Deforestation, private monopolization of lands, concentration of profits, soils and water pollution, biodiversity impoverishment, exploitation of vulnerable manpower, populations migration, violation of human rights are today the consequences of mass production of agro-fuels in Southern countries. To what conditions a fair re-appropriation and a sustainable development of agro-fuels production and consumption is foreseeable? The solutions require a re-shaping of economical and agricultural politics. The book gathers testimonies and analyses from specialists who have evaluated locally the consequences of these energy choices. (J.S.)

Pb pollution from leaded 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

2015-03-01

Exploitation of the extensive polymetallic deposits of the Andean Altiplano in South America since precolonial times has caused substantial emissions of neurotoxic lead (Pb) into the atmosphere; however, its historical significance compared to recent Pb pollution from leaded gasoline is not yet resolved. We present a comprehensive Pb emission history for the last two millennia for South America, based on a continuous, high-resolution, ice core record from Illimani glacier. Illimani is the highest mountain of the eastern Bolivian Andes and is located at the northeastern margin of the Andean Altiplano. The ice core Pb deposition history revealed enhanced Pb enrichment factors (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, Pb EFs increased by a factor of 3 compared to the emission level from metal production, which we attribute to gasoline-related Pb emissions. Our results show that anthropogenic Pb pollution levels from road traffic in South America exceed those of any historical metallurgy in the last two millennia, even in regions with exceptional high local metallurgical activity.

Pb pollution from leaded 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

2015-01-01

Exploitation of the extensive polymetallic deposits of the Andean Altiplano in South America since precolonial times has caused substantial emissions of neurotoxic lead (Pb) into the atmosphere; however, its historical significance compared to recent Pb pollution from leaded gasoline is not yet resolved. We present a comprehensive Pb emission history for the last two millennia for South America, based on a continuous, high-resolution, ice core record from Illimani glacier. Illimani is the highest mountain of the eastern Bolivian Andes and is located at the northeastern margin of the Andean Altiplano. The ice core Pb deposition history revealed enhanced Pb enrichment factors (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, Pb EFs increased by a factor of 3 compared to the emission level from metal production, which we attribute to gasoline-related Pb emissions. Our results show that anthropogenic Pb pollution levels from road traffic in South America exceed those of any historical metallurgy in the last two millennia, even in regions with exceptional high local metallurgical activity. PMID:26601147

Neotropical mammal diversity and the Great American Biotic Interchange: spatial and temporal variation in South America's fossil record

Science.gov (United States)

Carrillo, Juan D.; Forasiepi, Analía; Jaramillo, Carlos; Sánchez-Villagra, Marcelo R.

2015-01-01

The vast mammal diversity of the Neotropics is the result of a long evolutionary history. During most of the Cenozoic, South America was an island continent with an endemic mammalian fauna. This isolation ceased during the late Neogene after the formation of the Isthmus of Panama, resulting in an event known as the Great American Biotic Interchange (GABI). In this study, we investigate biogeographic patterns in South America, just before or when the first immigrants are recorded and we review the temporal and geographical distribution of fossil mammals during the GABI. We performed a dissimilarity analysis which grouped the faunal assemblages according to their age and their geographic distribution. Our data support the differentiation between tropical and temperate assemblages in South America during the middle and late Miocene. The GABI begins during the late Miocene (~10–7 Ma) and the putative oldest migrations are recorded in the temperate region, where the number of GABI participants rapidly increases after ~5 Ma and this trend continues during the Pleistocene. A sampling bias toward higher latitudes and younger records challenges the study of the temporal and geographic patterns of the GABI. PMID:25601879

Potential for spread of the white-nose fungus (Pseudogymnoascus destructans in the Americas: use of Maxent and NicheA to assure strict model transference

Directory of Open Access Journals (Sweden)

Luis E. Escobar

2014-11-01

Full Text Available Emerging infectious diseases can present serious threats to wildlife, even to the point of causing extinction. White- nose fungus (Pseudogymnoascus destructans is causing an epizootic in bats that is expanding rapidly, both geographically and taxonomically. Little is known of the ecology and distributional potential of this intercontinental pathogen. We address this gap via ecological niche models that characterise coarse resolution niche differences between fungus populations on dif- ferent continents, identifying areas potentially vulnerable to infection in South America. Here we explore a novel approach to identifying areas of potential distribution across novel geographic regions that avoids perilious extrapolation into novel environments. European and North American fungus populations show differential use of environmental space, but rather than niche differentiation, we find that changes are best attributed to climatic differences between the two continents. Suitable areas for spread of the pathogen were identified across southern South America; however caution should be taken to avoid underestimating the potential for spread of this pathogen in South America.

Potential for spread of the white-nose fungus (Pseudogymnoascus destructans) in the Americas: use of Maxent and NicheA to assure strict model transference.

Science.gov (United States)

Escobar, Luis E; Lira-Noriega, Andrés; Medina-Vogel, Gonzalo; Townsend Peterson, A

2014-11-01

Emerging infectious diseases can present serious threats to wildlife, even to the point of causing extinction. Whitenose fungus (Pseudogymnoascus destructans) is causing an epizootic in bats that is expanding rapidly, both geographically and taxonomically. Little is known of the ecology and distributional potential of this intercontinental pathogen. We address this gap via ecological niche models that characterise coarse resolution niche differences between fungus populations on different continents, identifying areas potentially vulnerable to infection in South America. Here we explore a novel approach to identifying areas of potential distribution across novel geographic regions that avoids perilious extrapolation into novel environments. European and North American fungus populations show differential use of environmental space, but rather than niche differentiation, we find that changes are best attributed to climatic differences between the two continents. Suitable areas for spread of the pathogen were identified across southern South America; however caution should be taken to avoid underestimating the potential for spread of this pathogen in South America.

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.

Optimizing Surveillance for South American Origin Influenza A Viruses Along the United States Gulf Coast Through Genomic Characterization of Isolates from Blue-winged Teal (Anas discors).

Science.gov (United States)

Ramey, A M; Walther, P; Link, P; Poulson, R L; Wilcox, B R; Newsome, G; Spackman, E; Brown, J D; Stallknecht, D E

2016-04-01

Relative to research focused on inter-continental viral exchange between Eurasia and North America, less attention has been directed towards understanding the redistribution of influenza A viruses (IAVs) by wild birds between North America and South America. In this study, we genomically characterized 45 viruses isolated from blue-winged teal (Anas discors) along the Texas and Louisiana Gulf Coast during March of 2012 and 2013, coincident with northward migration of this species from Neotropical wintering areas to breeding grounds in the United States and Canada. No evidence of South American lineage genes was detected in IAVs isolated from blue-winged teal supporting restricted viral gene flow between the United States and southern South America. However, it is plausible that blue-winged teal redistribute IAVs between North American breeding grounds and wintering areas throughout the Neotropics, including northern South America, and that viral gene flow is limited by geographical barriers further south (e.g., the Amazon Basin). Surveillance for the introduction of IAVs from Central America and northern South America into the United States may be further optimized through genomic characterization of viruses resulting from coordinated, concurrent sampling efforts targeting blue-winged teal and sympatric species throughout the Neotropics and along the United States Gulf Coast. © Published 2014. This article is a US Government work and is in the public domain in the USA.

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

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

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.

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)

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 ...

Checklist of fossil decapod crustaceans from tropical America. Part I: Anomura and Brachyura

Directory of Open Access Journals (Sweden)

Javier Luque

2017-10-01

Full Text Available Abstract Our knowledge of fossil crustaceans from the tropics has increased considerably during recent decades, thanks to novel findings and the re-examination of museum specimens. However, several previous records have been misidentified, numerous museum specimens have never been reported, and many new discoveries are yet to be published. Here, we present a detailed, up-to-date, and revised checklist for every marine, terrestrial, or freshwater fossil decapod crustacean occurrence from tropical America known to us, including their age, geographic occurrences, and related literature. We recognize the occurrence of at least 32 superfamilies, 69 families, 190 genera, and 415 species of brachyurans (‘true’ crabs, and anomurans (‘false’ crabs, hermit crabs, squat lobsters, and allies, several of them previously unknown. The checklist comprises records from three main geographic regions: 1 northern South America (Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Venezuela; 2 Central America and southern North America (Belize, Costa Rica, Honduras, Panama, Mexico, southern and central Florida; and 3 the Caribbean Islands + Bermuda (Anguilla, Antigua, Aruba, Bahamas, Barbados, Bermuda, Bonaire, Cuba, Curaçao, Dominican Republic, The Grenadines, Haiti, Jamaica, Puerto Rico, Saint Bartélemy, Saint Martin, Trinidad. Previous findings, new occurrences, and the revised systematic placement for several problematic/misidentified records, indicate that the fossil record of anomurans and brachyurans in tropical America is more diverse than previously envisioned, with a considerable degree of endemism at the genus- and species-levels.

Multiple-scale roost habitat comparisons of female Merriam's wild turkeys in the southern Black Hills, South Dakota

Science.gov (United States)

Daniel J. Thompson; Mark A. Rumble; Lester D. Flake; Chad P. Lehman

2009-01-01

Because quantity and quality of roosting habitat can affect Merriam's Wild Turkey (Meleagris gallopavo merriami) distribution, we described habitat characteristics of Merriam's turkey roost sites in the southern Black Hills of South Dakota. Varying proportions of Merriam's turkeys in the southern Black Hills depended on supplemental feed from livestock...

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.

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.

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.

[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.

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.

Evaluation of the UK Met Office's HadGEM3-RA and HadRM3P regional climate models within South America-CORDEX simulations: ENSO related interannual precipitation variability

Science.gov (United States)

Bozkurt, D.; Rojas, M.

2014-12-01

This study aims to investigate and compare the ability of the UK Met Office's HadGEM3-RA and HadRM3P regional climate models (RCMs) to simulate mean and interannual variability of precipitation over South America with a special focus on Chile. The HadGEM3-RA is a regional version of the newly developed HadGEM3 global model and the HadRM3P is based on the earlier HadCM3 global model. The RCMs simulations were carried out at 0.44o x 0.44o degree resolution over South America-CORDEX domain for the period 1989-2008. The initial and boundary conditions were provided by ERA-Interim Reanalysis data available at 6-h intervals with a resolution of 1.5o x 1.5o in the horizontal and 37 pressure levels. We compare the results against a number of observational datasets, including gridded dataset of CRU, UDEL, TRMM and GPCP. Moreover, available station data is derived from Direccion General de Aguas (DGA) mainly for Central Chile, which is the heartland of Chile with the highest population and important economic activities. The analysis is mainly focused on evaluating the abilities of the RCMs in simulating spatial pattern and ENSO related precipitation variability in different subregions of South America-CORDEX domain. In general, both RCMs have a good skill in reproducing spatial pattern and annual cycle of observed precipitation in climatically different subregions. However, both RCMs tend to underestimate precipitation in the Amazon Basin, which is more pronounced in the HadRM3P simulations. On the contrary, the RCMs tend to overestimate the precipitation over the Andes and southern Chile. The overestimation could be related to the physical core of the RCMs, but the discrepancies could also arise due to insufficient station network, especially in the mountainous areas, potentially yielding smaller precipitation quantities in the observed data than the true ones. In terms of interannual variability, the models capture ENSO related wet and dry interannual precipitation

Tectonic evolution of the Caribbean and northwestern South America: The case for accretion of two Late Cretaceous oceanic plateaus

Science.gov (United States)

Kerr, Andrew C.; Tarney, John

2005-04-01

It is widely accepted that the thickened oceanic crust of the Caribbean plate, its basaltic accreted margins, and accreted mafic terranes in northwestern South America represent the remnants of a single ca. 90 Ma oceanic plateau. We review geologic, geochemical, and paleomagnetic evidence that suggests that the Caribbean-Colombian oceanic plateau in fact represents the remnants of two different oceanic plateaus, both dated as ca. 90 Ma. The first of these plateaus, the Caribbean Plateau, formed ca. 90 Ma in the vicinity of the present-day Galapagos hotspot. Northeastward movement of the Farallon plate meant that this plateau collided with the proto Caribbean arc and northwestern South America Gorgona Plateau, formed at 26° 30°S, possibly at the site of the present-day Sala y Gomez hotspot. Over the next ˜45 m.y., this plateau was carried progressively northeastward on the Farallon plate and collided in the middle Eocene with the proto Andean subduction zone in northwestern South America. The recognition of a second ca. 90 Ma Pacific oceanic plateau strengthens the link between plateau formation and global oceanic anoxic events.

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.

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.

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

Trans-pacific glacial response to the Antarctic Cold Reversal in the southern mid-latitudes

Science.gov (United States)

Sagredo, Esteban A.; Kaplan, Michael R.; Araya, Paola S.; Lowell, Thomas V.; Aravena, Juan C.; Moreno, Patricio I.; Kelly, Meredith A.; Schaefer, Joerg M.

2018-05-01

Elucidating the timing and regional extent of abrupt climate events during the last glacial-interglacial transition (∼18-11.5 ka) is critical for identifying spatial patterns and mechanisms responsible for large-magnitude climate events. The record of climate change in the Southern Hemisphere during this time period, however, remains scarce and unevenly distributed. We present new geomorphic, chronological, and equilibrium line altitude (ELA) data from a climatically sensitive mountain glacier at Monte San Lorenzo (47°S), Central Patagonia. Twenty-four new cosmogenic 10Be exposure ages from moraines provide a comprehensive glacial record in the mid-latitudes of South America, which constrain the timing, spatial extent and magnitude of glacial fluctuations during the Antarctic Cold Reversal (ACR, ∼14.5-12.9 ka). Río Tranquilo glacier advanced and reached a maximum extent at 13.9 ± 0.7 ka. Three additional inboard moraines afford statistically similar ages, indicating repeated glacier expansions or marginal fluctuations over the ACR. Our record represents the northernmost robust evidence of glacial fluctuations during the ACR in southern South America, documenting not only the timing of the ACR maximum, but also the sequence of glacier changes within this climate event. Based on ELA reconstructions, we estimate a cooling of >1.6-1.8 °C at the peak of the ACR. The Río Tranquilo record along with existing glacial reconstructions from New Zealand (43°S) and paleovegetation records from northwestern (41°S) and central-west (45°S) Patagonia, suggest an uniform trans-Pacific glacier-climate response to an ACR trigger across the southern mid-latitudes. We posit that the equatorial migration of the southern westerly winds provides an adequate mechanism to propagate a common ACR signal across the Southern Hemisphere.

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)

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.

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.

Emissions from pre-Hispanic metallurgy in the South American atmosphere.

Directory of Open Access Journals (Sweden)

François De Vleeschouwer

Full Text Available Metallurgical activities have been undertaken in northern South America (NSA for millennia. However, it is still unknown how far atmospheric emissions from these activities have been transported. Since the timing of metallurgical activities is currently estimated from scarce archaeological discoveries, the availability of reliable and continuous records to refine the timing of past metal deposition in South America is essential, as it provides an alternative to discontinuous archives, as well as evidence for global trace metal transport. We show in a peat record from Tierra del Fuego that anthropogenic metals likely have been emitted into the atmosphere and transported from NSA to southern South America (SSA over the last 4200 yrs. These findings are supported by modern time back-trajectories from NSA to SSA. We further show that apparent anthropogenic Cu and Sb emissions predate any archaeological evidence for metallurgical activities. Lead and Sn were also emitted into the atmosphere as by-products of Inca and Spanish metallurgy, whereas local coal-gold rushes and the industrial revolution contributed to local contamination. We suggest that the onset of pre-Hispanic metallurgical activities is earlier than previously reported from archaeological records and that atmospheric emissions of metals were transported from NSA to SSA.

Emissions from pre-Hispanic metallurgy in the South American atmosphere.

Science.gov (United States)

De Vleeschouwer, François; Vanneste, Heleen; Mauquoy, Dmitri; Piotrowska, Natalia; Torrejón, Fernando; Roland, Thomas; Stein, Ariel; Le Roux, Gaël

2014-01-01

Metallurgical activities have been undertaken in northern South America (NSA) for millennia. However, it is still unknown how far atmospheric emissions from these activities have been transported. Since the timing of metallurgical activities is currently estimated from scarce archaeological discoveries, the availability of reliable and continuous records to refine the timing of past metal deposition in South America is essential, as it provides an alternative to discontinuous archives, as well as evidence for global trace metal transport. We show in a peat record from Tierra del Fuego that anthropogenic metals likely have been emitted into the atmosphere and transported from NSA to southern South America (SSA) over the last 4200 yrs. These findings are supported by modern time back-trajectories from NSA to SSA. We further show that apparent anthropogenic Cu and Sb emissions predate any archaeological evidence for metallurgical activities. Lead and Sn were also emitted into the atmosphere as by-products of Inca and Spanish metallurgy, whereas local coal-gold rushes and the industrial revolution contributed to local contamination. We suggest that the onset of pre-Hispanic metallurgical activities is earlier than previously reported from archaeological records and that atmospheric emissions of metals were transported from NSA to SSA.

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.

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...

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.

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.

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...

Comparisons of invasive plants in southern Africa originating from southern temperate, northern temperate and tropical regions

Directory of Open Access Journals (Sweden)

L. Henderson

2006-08-01

Full Text Available A subset of invasive alien plant species in southern Africa was analysed in terms of their history of introduction, rate of spread, countries/region of origin, taxonomy, growth forms, cultivated uses, weed status and current distribution in southern Africa, and comparisons made of those originating from south of the tropic of Capricorn, north of the tropic of Cancer and from the tropics. The subset of 233 species, belonging to 58 families, includes all important declared species and some potentially important species. Almost as many species originate from temperate regions (112 as from the tropics (121. Most southern temperate species came from Australia (28/36, most tropical species from tropical America (92/121 and most northern temperate species from Europe (including the Mediterranean and Asia (58/76. Transformers account for 33% of  all species. More transformers are of tropical origin (36 than of northern temperate (24 and southern temperate origin (18. However. 50% of southern temperate species are transformers, compared to 32% of northern temperate and 29% of tropical species. Southern temperate transformer species are mainly woody trees and shrubs that were established on a grand scale as silvicultural crops, barriers (hedges, windbreaks and screens and cover/binders. Most aquatics, herbs, climbers and succulent shrubs an. trom the tropics. Ornamentals are the single largest category of plants from all three regions, the tropics having contributed twice as many species as temperate regions.

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.

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…

Jaguar taxonomy and genetic diversity for southern Arizona, United States, and Sonora, Mexico

Science.gov (United States)

Culver, Melanie; Hein, Alexander Ochoa

2016-06-28

Executive SummaryThe jaguar is the largest Neotropical felid and the only extant representative of the genus Panthera in the Americas. In recorded history, the jaguars range has extended from the Southern United States, throughout Mexico, to Central and South America, and they occupy a wide variety of habitats. A previous jaguar genetic study found high historical levels of gene flow among jaguar populations over broad areas but did not include any samples of jaguar from the States of Arizona, United States, or Sonora, Mexico. Arizona and Sonora have been part of the historical distribution of jaguars; however, poaching and habitat fragmentation have limited their distribution until they were declared extinct in the United States and endangered in Sonora. Therefore, a need was apparent to have this northernmost (Arizona/Sonora) jaguar population included in an overall jaguar molecular taxonomy and genetic diversity analyses. In this study, we used molecular genetic markers to examine diversity and taxonomy for jaguars in the Northwestern Jaguar Recovery Unit (NJRU; Sonora, Sinaloa, and Jalisco, Mexico; and southern Arizona and New Mexico, United States) relative to jaguars in other parts of the jaguar range (Central and South America). The objectives of this study were to:Collect opportunistic jaguar samples (hide, blood, hair, saliva, and scat), from historical and current individuals, that originated in NJRU areas of Arizona, New Mexico, and Sonora;Use these samples to assess molecular taxonomy of NJRU jaguars compared to data from a previous study of jaguars rangewide; andDevelop suggestions for conservation of NJRU jaguars based on the results.

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

South[ern] Africa's "Dar ul-'Ulums": Institutions of Social Change for the Common Good?

Science.gov (United States)

Haron, Muhammed

2014-01-01

Muslim communities in principally non-Muslim nation states (e.g. South Africa, United States of America, the United Kingdom and the Netherlands) established a plethora of Muslim theological institutions. They have done so with the purpose of educating and reinforcing their Muslim identity. These educational structures have given rise to numerous…

Craton Heterogeneity in the South American Lithosphere

Science.gov (United States)

Lloyd, S.; Van der Lee, S.; Assumpcao, M.; Feng, M.; Franca, G. S.

2012-04-01

We investigate structure of the lithosphere beneath South America using receiver functions, surface wave dispersion analysis, and seismic tomography. The data used include recordings from 20 temporary broadband seismic stations deployed across eastern Brazil (BLSP02) and from the Chile Ridge Subduction Project seismic array in southern Chile (CRSP). By jointly inverting Moho point constraints, Rayleigh wave group velocities, and regional S and Rayleigh wave forms we obtain 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 correlation between crustal thickness and geologic age can be 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. We also invert for S velocity structure and estimate the depth of the lithosphere-asthenosphere boundary (LAB) in Precambrian South America. The new model reveals a relatively thin lithosphere throughout most of Precambrian South America (< 140 km). Comparing LAB depth with lithospheric age shows they are overall positively correlated, whereby the thickest lithosphere occurs in the relatively small Saõ Francisco craton (200 km). However, within the larger Amazonian craton the younger lithosphere is thicker, indicating that locally even larger cratons are not protected from erosion or reworking of the lithosphere.

An Investigation of the Migration of Africanized Honey Bees into the Southern United States

Science.gov (United States)

Navarro, Hector

1997-01-01

It is estimated that Apis mellifera scutellata, a honey bee subspecies from Africa, now extends over a 20 million square kilometer range that includes much of South America and practically all of Central America, and recently has been introduced to the southern United States. African honeybees were introduced into Brazil in 1956 by a Brazilian geneticist, Mr. Warwick Kerr. At the insistence of the Brazilian Ministry of Agriculture, in 1957, 26 colonies were accidentally released in a eucalyptus forest outside S5o Paulo. The swelling front of the bees was recorded as traveling between 80 and 500 kilometers a year. David Roubik, one of the original killer bee team members estimated that there were one trillion individual Africanized/African honey bees in Latin America. An estimate that is thought to be conservative.

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.

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

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.

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).

Early German Plans for a Southern Observatory

Science.gov (United States)

Wolfschmidt, Gudrun

As early as the 18th and 19th centuries, French and English observers were active in South Africa. Around the beginning of the 20th century the Heidelberg astronomer Max Wolf (1863-1932) proposed a southern observatory. In 1907 Hermann Carl Vogel (1841-1907), director of the Astrophysical Observatory Potsdam, suggested a southern station in Spain. His ideas for building an observatory in Windhuk for photographing the sky and measuring the solar constant were taken over by the Göttingen astronomers. In 1910 Karl Schwarzschild (1873-1916), after having visited the observatories in America, pointed out the usefulness of an observatory in South West Africa, where it would have better weather than in Germany and also give access to the southern sky. Seeing tests were begun in 1910 by Potsdam astronomers, but WW I stopped the plans. In 1928 Erwin Finlay-Freundlich (1885-1964), inspired by the Hamburg astronomer Walter Baade (1893-1960), worked out a detailed plan for a southern observatory with a reflecting telescope, spectrographs and an astrograph with an objective prism. Paul Guthnick (1879-1947), director of the Berlin observatory, in cooperation with APO Potsdam and Hamburg, made a site survey to Africa in 1929 and found the conditions in Windhuk to be ideal. Observations were started in the 1930s by Berlin and Breslau astronomers, but were stopped by WW II. In the 1950s, astronomers from Hamburg and The Netherlands renewed the discussion in the framework of European cooperation, and this led to the founding of ESO in 1963, as is well described by Blaauw (1991). Blaauw, Adriaan: ESO's Early History. The European Southern Observatory from Concept to Reality. Garching bei München: ESO 1991.

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.

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.

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.

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Région: Americas, Argentina, South America, Asia, India, South and Central Asia, Africa, Kenya, South of Sahara, Mexico, North and Central America, Southern Africa, Global. Programme: Emploi et ... Sujet: DIET, FOOD CROPS, CROP DIVERSIFICATION, MICRONUTRIENTS, BIODIVERSITY. Région: Africa, Benin, South ...

The South-American distribution and southernmost record of Biomphalaria peregrina—a potential intermediate host of schistosomiasis

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Alejandra Rumi

2017-05-01

Full Text Available Schistosomiasis remains a major parasitic disease, endemic in large parts of South America. Five neotropical species of Biomphalaria have been found to act as intermediate hosts of Schistosoma mansoni in natural populations, while others have been shown to be susceptible in experimental infections, although not found infected in the field. Among these potential intermediate hosts, Biomphalaria peregrina represents the most widespread species in South America, with confirmed occurrence records from Venezuela to northern Patagonia. In this study, we report the southernmost record for the species at the Pinturas River, in southern Patagonia, which finding implies a southward reassessment of the limit for the known species of this genus. The identities of the individuals from this population were confirmed through morphological examination, and by means of two mitochondrial genes, cytochrome oxidase subunit I (COI and 16S-rRNA. With both markers, phylogenetic analyses were conducted in order to compare the genetic background of individuals from the Pinturas River with previously genetically characterized strains of B. peregrina from various South-American locations. In addition, we produced a potential distribution model of B. peregrina in South America and identified the environmental variables that best predict that distribution. The model was estimated through a maximum entropy algorithm and run with occurrence points obtained from several sources, including the scientific literature and international databases, along with climatic and hydrographic variables. Different phylogenetic analyses with either the COI or 16S-rRNA sequences did not conflict, but rather gave very similar topological organizations. Two major groups were identified, with sequences from the Pinturas River grouping together with haplotypes from subtropical and temperate regions. The model developed had a satisfactory performance for the study area. We observed that the areas

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

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

2018-01-01

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

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

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

Influence of the May Southern annular mode on the South China Sea summer monsoon

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Liu, Ting; Li, Jianping; Li, YanJie; Zhao, Sen; Zheng, Fei; Zheng, Jiayu; Yao, Zhixiong

2017-07-01

The possible impact of the May Southern Hemisphere (SH) annular mode (SAM) on the following South China Sea (SCS) summer monsoon (SCSSM) is examined. A close inverse relationship between the two is revealed in the observations. The simultaneous South Pacific dipole (SPD), a dipole-like sea surface temperature anomaly pattern in the South Pacific, acts as the "oceanic bridge" to preserve the May SAM signal and prolong it into June-September. Observational evidence and numerical simulations both demonstrate that the SPD communicates its large thermal inertia signal to the atmosphere, regulating the Southern Pacific Subtropical Jet (SPSJ) variability over eastern Australia. Corresponding to the adjustment of circulation associated with the SPSJ is a prominent tripolar cross-Pacific teleconnection pattern stretching from the SH middle-high latitudes into the NH East Asia coastal region, referred to as the South-North Pacific (SNP) teleconnection pattern. Wave ray tracing analysis manifests that the SNP acts as the "atmospheric bridge" to propagate the related wave energy across the equator and into the Maritime Continent and SCS monsoon region, modulating the vertical motion and middle-lower tropospheric flows, and favoring the out-of-phase variation of the SCSSM. Therefore, the "coupled oceanic-atmospheric bridge" process and the related Rossby wave energy transmission are possible mechanisms for the significant influence of the May SAM on the variability of the following SCSSM. Therefore, the May SAM provides a fresh insight into the prediction of the SCSSM from the perspective of the SH high latitudes.

The coexistence of peace and conflict in South America: toward a new conceptualization of types of peace

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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.

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

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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.

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.

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Sujet: Biodiversity, INTELLECTUAL PROPERTY. Région: Asia, China, Far East Asia, India, South ... Région: Americas, Argentina, South America, Asia, India, South and Central Asia, Africa, Kenya, South of Sahara, Mexico, North and Central America, Southern Africa, Global. Programme: Emploi et croissance. Financement ...

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

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…

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

ECLAMC Study: prevalence patterns of hypospadias in South America: multi-national analysis over a 24-year period

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Nicolás Fernández

Full Text Available ABSTRACT Objective To evaluate prevalence trends of hypospadias in South-America it is essential to perform multicenter and multinational studies with the same methodology. Herein we present systematic data as part of an international multicenter initiative evaluating congenital malformations in South America over a 24-year period. Materials and Methods A nested case-control study was conducted using the Latin American Collaborative Study of Congenital Malformations (ECLAMC, between January 1989 and December 2012. Cases were stratified as isolated (IH and non-isolated hypospadias (NIH. Global prevalence was calculated and discriminated by country. Associations between birth weight and gestational age, and NIH distribution by associated abnormality and severity of hypospadias, were analyzed. Results A total of 159 hospitals from six countries participated, reporting surveillance on 4.020.384 newborns. A total of 4.537 hypospadias cases were detected, with a global prevalence of 11.3/10.000 newborns. Trend analyses showed in Chile, Brazil and Uruguay a statistically significant increase in prevalence. Analysis of severity and associated anomalies did not to find an association for distal cases, but did for proximal (RR=1.64 [95% CI=1.33-2.03]. Conclusion This is one of only a few Latin American multicenter studies reporting on the epidemiology of hypospadias in South America in the last two decades. Our data adds to evidence suggesting an increase in some countries in the region at different times. There were also variations in prevalence according to severity. This study adds to literature describing associated anomalies at a hospital-based level.

ECLAMC Study: Prevalence patterns of hypospadias in South America: Multi-national analysis over a 24-year period.

Science.gov (United States)

Fernández, Nicolás; Pérez, Jaime; Monterrey, Pedro; Poletta, Fernando A; Bägli, Darius J; Lorenzo, Armando J; Zarante, Ignacio

2017-01-01

To evaluate prevalence trends of hypospadias in South-America it is essential to perform multicenter and multinational studies with the same methodology. Herein we present systematic data as part of an international multicenter initiative evaluating congenital malformations in South America over a 24-year period. A nested case-control study was conducted using the Latin American Collaborative Study of Congenital Malformations (ECLAMC), between January 1989 and December 2012. Cases were stratified as isolated (IH) and non-isolated hypospadias (NIH). Global prevalence was calculated and discriminated by country. Associations between birth weight and gestational age, and NIH distribution by associated abnormality and severity of hypospadias, were analyzed. A total of 159 hospitals from six countries participated, reporting surveillance on 4.020.384 newborns. A total of 4.537 hypospadias cases were detected, with a global prevalence of 11.3/10.000 newborns. Trend analyses showed in Chile, Brazil and Uruguay a statistically significant increase in prevalence. Analysis of severity and associated anomalies did not to find an association for distal cases, but did for proximal (RR=1.64 [95% CI=1.33-2.03]). This is one of only a few Latin American multicenter studies reporting on the epidemiology of hypospadias in South America in the last two decades. Our data adds to evidence suggesting an increase in some countries in the region at different times. There were also variations in prevalence according to severity. This study adds to literature describing associated anomalies at a hospital-based level. Copyright® by the International Brazilian Journal of Urology.

The MIS 3 maximum of the Torres del Paine and Última Esperanza ice lobes in Patagonia and the pacing of southern mountain glaciation

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García, Juan-Luis; Hein, Andrew S.; Binnie, Steven A.; Gómez, Gabriel A.; González, Mauricio A.; Dunai, Tibor J.

2018-04-01

The timing, structure and termination of the last southern mountain glaciation and its forcing remains unclear. Most studies have focused on the global Last Glacial Maximum (LGM; 26.5-19 ka) time period, which is just part of the extensive time-frame within the last glacial period, including Marine Isotope Stages 3 and 4. Understanding the glacial fluctuations throughout the glacial period is a prerequisite for uncovering the cause and climate mechanism driving southern glaciation and the interhemispheric linkages of climate change. Here, we present an extensive (n = 65) cosmogenic 10Be glacier chronology derived from moraine belts marking the pre-global LGM extent of the former Patagonian Ice Sheet in southernmost South America. Our results show the mountain ice sheet reached its maximum extent at 48.0 ± 1.8 ka during the local LGM, but attained just half this extent at 21.5 ± 1.8 ka during the global LGM. This finding, supported by nearby glacier chronologies, indicates that at orbital time scales, the southern mid-latitude glaciers fluctuated out-of-phase with northern hemisphere ice sheets. At millennial time-scales, our data suggest that Patagonian and New Zealand glaciers advanced in unison with cold Antarctic stadials and reductions in Southern Ocean sea surface temperatures. This implies a southern middle latitudes-wide millennial rhythm of climate change throughout the last glacial period linked to the north Atlantic by the bipolar seesaw. We suggest that winter insolation, acting alongside other drivers such as the strength and/or position of the southern westerlies, controlled the extents of major southern mountain glaciers such as those in southernmost South America.

Nasal mites (Mesostigmata, Rhinonyssidae in Sternidae (Aves: Charadriiformes on the southern Coast of Brazil

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Diego Silva da Silva

2018-02-01

Full Text Available Abstract Six species of birds of the family Sternidae are often found on the southern coast of South America. Sterna trudeaui, S. hirundinacea, Thalasseus maximus, T. acuflavidus and Sternula superciliaris are South American residents and Sterna hirundo, a Nearctic migrant. At least 500 species of nasal mites have been described around the world, and Rhinonyssidae is the most diverse family. These mites are bloodsucking endoparasites that inhabit the respiratory system of birds. This study aimed to report on occurrences of nasal mites in Sternidae on the southern coast of Brazil. Of the 106 birds analyzed, 8.5% (9 birds were parasitized by nasal mites. This report provides the first record in the Neotropical region for two mite species, Sternostoma boydi and Larinyssus orbicularis parasitizing Thalasseus acuflavidus and Sternula superciliaris. No nasal mites were found in Sterna trudeaui or Thalasseus maximus. One host individual (T. acuflavidus was parasitized by two species of nasal mites, S. boydi and L. orbicularis.

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.)

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

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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.

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.

Identity, reproductive potential, distribution, ecology and management of invasive Pomacea maculata in the southern United States

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Burks, Romi L.; Bernatis, Jennifer; Byers, James E.; Carter, Jacoby; Martin, Charles M.; McDowell, William G.; Van Dyke, Jess; Joshi, R. C.; Cowie, R. H.; Sebastian, L. S.

2017-01-01

Established populations of introduced Pomacea maculata, a highly fecund, large species of apple snail native to South America, now occur throughout southeast Asia, in Spain and extensively across the southern United States. Substantial research on nonnative apple snails takes place in Southeast Asia and has frequently identified apple snails as P. canaliculata. That these Asian populations represent at least two Pomacea species, P. canaliculata and P. maculata, has been confirmed through anatomical and genetic

DESIGNING DEMOCRACY IN SOUTH AMERICA Projetando a democracia na América do Sul

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Erinaldo Ferreira Carmo

2012-12-01

Full Text Available Since the 1980s, when South America pulled away the shadow of authoritarianism and again to breathe the air of freedom, the democratization process has been strengthened in the region, within a very dynamic and not uniform among the states. In this chapter we describe the construction of regional democracy and the changes occurring every decade, including the prospects for this ongoing, with reference to the historical and political process of each South American State, including the ostensible expansion of citizenship rights and political involvement of citizen, but 186. GeoTextos, vol. 8, n. 2, dez. 2012. E. Carmo, S. Pacheco. 185-210 without ceasing to understand the fragility of political institutions, the drama of corruption, the obstacles posed by drug trafficking and the guerrilla groups, the constraints to economic growth and rising, but still incipient, organization of the Southern Common Market – Mercosul.Desde a década de 1980, quando a América do Sul afastou a sombra do autoritarismo e voltou a respirar ares de liberdade, o processo de democratização vem se fortalecendo na região, dentro de um dinamismo próprio e sem uniformidade entre os Estados. Neste artigo descrevemos a construção desta democracia regional e as transformações ocorridas a cada década, incluindo as perspectivas em curso, tomando como referência o processo histórico e político de cada Estado sul-americano, compreendendo a ostensiva ampliação dos direitos de cidadania e do envolvimento político do cidadão, mas sem deixar de compreender a fragilidade das instituições políticas, o drama da corrupção, os entraves impostos pelo narcotráfico e pelos grupos guerrilheiros, as limitações ao crescimento econômico e a ascendente, mas ainda incipiente, organização do Mercado Comum do Sul – Mercosul.

Single nucleotide polymorphisms in native South American Atlantic coast populations of smooth shelled mussels: hybridization with invasive European Mytilus galloprovincialis.

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Zbawicka, Małgorzata; Trucco, María I; Wenne, Roman

2018-02-22

Throughout the world, harvesting of mussels Mytilus spp. is based on the exploitation of natural populations and aquaculture. Aquaculture activities include transfers of spat and live adult mussels between various geographic locations, which may result in large-scale changes in the world distribution of Mytilus taxa. Mytilus taxa are morphologically similar and difficult to distinguish. In spite of much research on taxonomy, evolution and geographic distribution, the native Mytilus taxa of the Southern Hemisphere are poorly understood. Recently, single nucleotide polymorphisms (SNPs) have been used to clarify the taxonomic status of populations of smooth shelled mussels from the Pacific coast of South America. In this paper, we used a set of SNPs to characterize, for the first time, populations of smooth shelled mussels Mytilus from the Atlantic coast of South America. Mytilus spp. samples were collected from eastern South America. Six reference samples from the Northern Hemisphere were used: Mytilus edulis from USA and Northern Ireland, Mytilus trossulus from Canada, and Mytilus galloprovincialis from Spain and Italy. Two other reference samples from the Southern Hemisphere were included: M. galloprovincialis from New Zealand and Mytilus chilensis from Chile. Fifty-five SNPs were successfully genotyped, of which 51 were polymorphic. Population genetic analyses using the STRUCTURE program revealed the clustering of eight populations from Argentina (Mytilus platensis) and the clustering of the sample from Ushuaia with M. chilensis from Chile. All individuals in the Puerto Madryn (Argentina) sample were identified as M. platensis × M. galloprovincialis F2 (88.89%) hybrids, except one that was classified as Mediterranean M. galloprovincialis. No F1 hybrids were observed. We demonstrate that M. platensis (or Mytilus edulis platensis) and M. chilensis are distinct native taxa in South America, which indicates that the evolutionary histories of Mytilus taxa along the

The palaeobiogeography of South American gomphotheres

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Spencer G. Lucas

2013-01-01

Full Text Available Gomphotheriid proboscideans reached South America as Late Cenozoic immigrants from North America. However, disagreements over alpha taxonomy, age dating and phylogenetic relationships have produced three competing hypotheses about this immigration: (1 a single gomphothere immigration took place soon after the ~3 Ma closure of the Panamanian isthmus; (2 two separate gomphothere immigrations took place after closure of the isthmus; or (3 an earlier, Late Miocene (before 9 Ma immigration brought gomphotheres into South America. A critical re-evaluation of the alpha taxonomy, age dating and phylogenetic relationships of Neotropical gomphotheres identifies two valid genera of South American gomphotheres, Cuvieronius and Notiomastodon (= “Haplomastodon”, = “Stegomastodon” from South America and recognizes “Amahuacatherium” as an invalid genus likely based on a specimen of Notiomastodon. The oldest well-dated South American gomphothere fossil is Marplatan, ~2.5 Ma, from Argentina. The case for an age of “Amahuacatherium” older than 9 Ma is refuted by mammalian biostratigraphy and a re-evaluation of the relevant magnetostratigraphy. North American Rhynchotherium descended from Gomphotherium during the Late Hemphillian (~5–6 Ma and gave rise to Cuvieronius in North America by the end of the Blancan (~2 Ma time. Notiomastodon evolved from Cuvieronius in South America during the Pleistocene. The case for a close relationship between the Neotropical gomphotheres and Sinomastodon from China is rejected. Central America was not a center of endemic gomphothere evolution and merely acted as a pathway for the immigration of gomphotheres from north to south: Gomphotherium into Central America during the Miocene, Cuvieronius to Central America by Early Pleistocene time and on to South America. After closure of the Panamanian isthmus, Cuvieronius immigrated to South America, where it gave rise to Notiomastodon by Middle Pleistocene time. The

Over-harvesting driven by consumer demand leads to population decline: big-leaf mahogany in South America

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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...

Some preliminary results of a worldwide seismicity estimation: a case study of seismic hazard evaluation in South America

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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

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

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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.

Radiometric ages of some igneous rocks from the southern and southwestern coalfields of New South Wales

International Nuclear Information System (INIS)

Carr, P.F.; Facer, R.A.

1980-01-01

Samples from six igneous rock units of the Southern and Southwestern Coalfields (Sydney Basin) of New South Wales have been dated using the K-Ar radiometric technique. The following ages were determined: a dolerite from Towradgi, 243 +- 10 MY; a dolerite from a diamond-drill hole at Sutton Forest, 202 +- 8 MY; the Bong Bong Basalt, 190 +- 8 MY; the Good Dog Lamprophyre, 101 +- 4 MY; a teschenite from South Bulli coal mine 74.0 +- 3.6 MY; and a dolerite from Robertson, 63.8 +- 3.2 MY. Combination of these new ages wth previously-published ages indicates that igneous activity in the Southern and Southwestern Coalfields occurred during four discrete periods of time - Middle-to-Late Permian; Late Triassic to Early Jurassic; mid-Cretaceous (only the Good Dog Lamprophyre has yielded such an age); and latest Cretaceous to Late Oligocene

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

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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.

LATTES: a new gamma-ray detector concept for South America

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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.

Human immunodeficiency virus, AIDS, and drug consumption in South America and the Caribbean: epidemiological evidence and initiatives to curb the epidemic.

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Hacker, Mariana A; Malta, Monica; Enriquez, Melissa; Bastos, Francisco I

2005-01-01

The paper reviews data on drug use in relation to the spread of human immunodeficiency virus and AIDS in South America and the Caribbean. Information was gathered by thoroughly reviewing major bibliographic databanks, web sites of international institutions and regional networks working with substance misuse or human immunodeficiency virus and AIDS, and abstracts from conferences and meetings. Although some gaps remain, a growing body of evidence documents the significant role of injected cocaine in the Brazilian and Southern Cone epidemics. The Caribbean and the Andean areas have thus far been spared in large part from the spread of injection drug use and its consequences, but the situation has been changing in Southern Cone countries towards a higher prevalence of harmful injection habits. Additional challenges have been posed by the increasing availability of heroin in the Andean Area and the abuse of crack cocaine and its impact on the sexual transmission of human immunodeficiency virus in many cities. Harm reduction strategies have been established in most areas of Brazil and are gaining momentum in Argentina. Other countries in the Region still face serious limitations due to restrictive legislation and lack of broader support. Greater participation of Latin American and Caribbean countries in research protocols and continued debate on both successful and failed experiences should be encouraged in order to minimize existing barriers to the full adoption of effective measures to curb the human immunodeficiency virus and AIDS epidemic in this Region.

Brazilian peppertree (Schinus terebinthifolius) in Florida and South America: Evidence of a possible niche shift driven by hybridization

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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...

George Augustus Sala and the English Middle-Class View of America

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Peter Blake

2009-11-01

Full Text Available In 1850 the journalist George Augustus Sala appealed to the perceived moral superiority of the English middle classes by satirising American slavery and Southern slave-owners. When Sala first visited America in 1863, as Special Correspondent for the 'Daily Telegraph' during the Civil War, his articles were some of the most pro-slavery, pro-Southern and anti-Union pieces the English public had read. Sala attacked all aspects of Northern life, disputed the North’s reasons for war, criticised their treatment of free blacks and maintained that claims of barbarity towards slaves in the South had been grossly exaggerated. Despite his previous pronouncements, Sala returned to America for the 'Telegraph' in 1879 and was greeted favourably wherever he went. He declared that he had been a ‘fool’ for supporting the wrong side during the Civil War but still maintained that African-Americans had been better off under the slave-system and that they were incapable of practising self-government. He observed that America was now ‘a wonderful country and a wonderful people.’ Although hitherto neglected in scholarly debates on Anglo-American relations in the nineteenth century, this paper will highlight Sala’s importance in this context, not least because of the large readership he commanded. As a journalist for the newspaper with the largest daily circulation in the world, Sala’s fluctuating and controversial opinions on America were read by some 250,000 middle class English men and women every day. This essay will also question to what extent Sala’s changing perceptions of America were influenced by the contemporary racial discourse of other middle-class commentators like Thomas Carlyle, Charles Dickens and Richard Burton, and by events like the Governor Eyre Affair. Using recent scholarship in the field of racial theory by critics including Catherine Hall, Robert Young and Tim Barringer, this paper will reassess English middle-class views on

First record of Smilodon fatalis Leidy, 1868 (Felidae, Machairodontinae) in the extra-Andean region of South America (late Pleistocene, Sopas Formation), Uruguay: Taxonomic and paleobiogeographic implications

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Manzuetti, Aldo; Perea, Daniel; Ubilla, Martín; Rinderknecht, Andrés

2018-01-01

The Felidae are known in South America from the Ensenadan Stage/Age onwards. Among them, machairodonts of the genus Smilodon stand out. Three species are recognized, and all three are present on the continent: S. gracilis from the early-middle Pleistocene in north-east Venezuela; S. fatalis, found only in Lujanian sediments on the west side of the Andes (north-west of Peru and south-west of Ecuador); and S. populator, which inhabited the eastern part of the Andes during the Ensenadan and Lujanian. This distribution has led to the suggestion that the last two felids were allopatric during the Lujanian. Here, we report the first evidence of S. fatalis in the eastern part of the continent (Sopas Formation, late Pleistocene of Uruguay), based on an almost complete skull. This finding not only enlarges its distribution in South America but questions the idea of allopatric distribution. It also adds a new component to the mammalian predator trophic level of Uruguay, with the capacity to predate large South American herbivores and megaherbivores. A revision of materials previously assigned to S. populator in the extra-Andean zone of South America will be required.

Korean Investments in Latin America: Current Status and Prospects

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Taik-Hwan Jyoung

1998-06-01

Full Text Available This thesis first took an overall look at the relationship between Asia and Central and South America. Meanwhile, this thesis studied the growth potential of these two continents and the rapid growth trend compared with other areas. Based on these, this thesis emphasized the necessity of the cooperation between Asia and Central and South America, which has been alienated for a long period. Upon studying of this thesis, the reader will track the connection of the overseas investment strategy of Korea to the domestic and overseas economic factors while analyzing its motivation and feature, etc. Also, it analyzes Korea's future investment in Central and South America as comparing with the strategies of Japan and Taiwan. Besides, in this thesis the author is trying to get future-oriented experiences from the analyses in areas such as trade, investment experience, culture difference and personnel exchange, and the prospect of the relationship between Korea and Central and South America. This thesis brought forward the 'blueprint' about promoting the cooperation between Asia and Central and South America, such as to organize the meeting for the new setting summit conference of Asian and Central American leaders, to add members from Central and South America countries to the MERCOSUR of APEC, to expand items in order to promote mutual-communication.

Paleohydrology of tropical South America and paleoceanography of the tropical Atlantic as deduced from two new sediment cores on the Brazilian continental slope

Science.gov (United States)

Nace, T.; Baker, P. A.; Dwyer, G. S.; Silva, C. G.; Hollander, D. J.; Rigsby, C. A.; Giosan, L.; Burns, S. J.

2011-12-01

Paleoclimate/paleoceanographic reconstructions of the Amazon Basin, Brazilian Nordeste, and western equatorial Atlantic have been undertaken on two new sediment cores located on the Brazilian continental slope (Core CDH-5 at 1708 mbsl, 4N, 48W, 32m long, ~30 ka record; Core CDH-86 at 3708 mbsl, 0N/S, 44W, 30m long, ~100ka record). High-resolution XRF analyses of Fe, Ti, and Ca are used to define the paleohydrologic history of the adjacent continent at both sites. Large and abrupt excursions of Ti/Ca ratios are observed in both cores, but are significantly better defined in the southern core, representative of Nordeste conditions. In this core there are a total of 9 Ti/Ca excursions, the oldest recovered dating to ~98ka. These excursions correlate well with Heinrich events from the North Atlantic. High-resolution stable oxygen isotopic analysis and Mg/Ca paleothermometry undertaken on the near-surface-dwelling planktic foraminiferal species Globierinoides ruber provide a picture of paleoceanographic forcings in the western equatorial Atlantic. The northern and southern cores respectively exhibit rapid warming of ~3C and ~3.5C between the last glacial maximum and the early Holocene. Furthermore, in almost all cases, during the last glacial stage, there was a 0.5C to 2C warming of the western equatorial Atlantic during the periods of high Ti/Ca ratios that correlate with Heinrich events. Thus, as observed in some previous studies, the western equatorial Atlantic was warm and the adjacent southern tropical continent was wet at the same time that the high-latitude North Atlantic was cold. The largely accepted paradigm is that Northern hemisphere cold events result in a southward migration of the Intertropical Convergence Zone (ITCZ), contributing to drier conditions at the northern extent of the ITCZ annual range (Cariaco Basin) and increased precipitation in the southern tropics of South America. The ITCZ appears to have been influenced by millennial variability of

Study of southern CHAONAN sag lower continental slope basin deposition character in Northern South China Sea

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Tang, Y.

2009-12-01

Northern South China Sea Margin locates in Eurasian plate,Indian-Australia plate,Pacific Plates.The South China Sea had underwent a complicated tectonic evolution in Cenozoic.During rifting,the continental shelf and slope forms a series of Cenozoic sedimentary basins,including Qiongdongnan basin,Pearl River Mouth basin,Taixinan basin.These basins fill in thick Cenozoic fluviolacustrine facies,transitional facies,marine facies,abyssal facies sediment,recording the evolution history of South China Sea Margin rifting and ocean basin extending.The studies of tectonics and deposition of depression in the Southern Chaonan Sag of lower continental slope in the Norther South China Sea were dealt with,based on the sequence stratigraphy and depositional facies interpretation of seismic profiles acquired by cruises of“China and Germany Joint Study on Marine Geosciences in the South China Sea”and“The formation,evolution and key issues of important resources in China marginal sea",and combining with ODP 1148 cole and LW33-1-1 well.The free-air gravity anomaly of the break up of the continental and ocean appears comparatively low negative anomaly traps which extended in EW,it is the reflection of passive margin gravitational effect.Bouguer gravity anomaly is comparatively low which is gradient zone extended NE-SW.Magnetic anomaly lies in Magnetic Quiet Zone at the Northern Continental Margin of the South China Sea.The Cenozoic sediments of lower continental slope in Southern Chaonan Sag can be divided into five stratum interface:SB5.5,SB10.5,SB16.5,SB23.8 and Hg,their ages are of Pliocene-Quaternary,late Miocene,middle Miocene,early Miocene,paleogene.The tectonic evolution of low continental slope depressions can be divided into rifting,rifting-depression transitional and depression stages,while their depositional environments change from river to shallow marine and abyssa1,which results in different topography in different stages.The topographic evolvement in the study

Ocean deformation processes at the Caribbean-North America-South America triple junction: Initial results of the 2007 ANTIPLAC marine survey

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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.

The past, present and future distribution of a deep-sea shrimp in the Southern Ocean

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Zeenatul Basher

2016-02-01

Full Text Available Shrimps have a widespread distribution across the shelf, slope and seamount regions of the Southern Ocean. Studies of Antarctic organisms have shown that individual species and higher taxa display different degrees of sensitivity and adaptability in response to environmental change. We use species distribution models to predict changes in the geographic range of the deep-sea Antarctic shrimp Nematocarcinus lanceopes under changing climatic conditions from the Last Glacial Maximum to the present and to the year 2100. The present distribution range indicates a pole-ward shift of the shrimp population since the last glaciation. This occurred by colonization of slopes from nearby refugia located around the northern part of Scotia Arc, southern tip of South America, South Georgia, Bouvet Island, southern tip of the Campbell plateau and Kerguelen plateau. By 2100, the shrimp are likely to expand their distribution in east Antarctica but have a continued pole-ward contraction in west Antarctica. The range extension and contraction process followed by the deep-sea shrimp provide a geographic context of how other deep-sea Antarctic species may have survived during the last glaciation and may endure with projected changing climatic conditions in the future.

Molecular paleoparasitological diagnosis of Ascaris sp. from coprolites: new scenery of ascariasis in pre-Colombian South America times

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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.

A review of the genus Orionis Shaw (Hymenoptera: Braconidae: Euphorinae) and first records of the genus from South America and the Oriental Region.

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Bortoni, Marco Aurélio; Shimbori, Eduardo Mitio; Shaw, Scott Richard; Souza-Gessner, Carolina DA Silva; Penteado-Dias, Angélica Maria

2016-12-16

Orionis is a small Neotropical euphorine genus, currently in the tribe Perilitini. Although the biology of the genus is unknown, Orionis eximius (Muesebeck) was described from a single female specimen reared from a cocoon associated with Lantana camara. Here, we present a taxonomic revision of Orionis and the first records of the genus from South America and Thailand, with descriptions of three new species: O. brasiliensis sp. nov., O. ecuadoriensis sp. nov. and O. orientalis sp. nov. We also report the first record of O. eximius from South America (Ecuador). A revised key for the described species is presented.

Seasonal, daily activity, and habitat use by three sympatric pit vipers (Serpentes, Viperidae) from southern Brazil

OpenAIRE

ROCHA, MARCELO C.; HARTMANN, PAULO A.; WINCK, GISELE R.; CECHIN, SONIA Z.

2014-01-01

Viperid snakes are widely distributed in the South America and the greater distribution range of the family is found at the Crotalinae subfamily. Despite the abundance of this snakes along their geographic distribution, some ecological aspects remain unknown, principally at subtropical areas. In the present study, we evaluated the activity (daily and seasonal) and the use of the habitat by Bothrops diporus, B. jararaca andB. jararacussu, in an Atlantic Forest area at southern Brazil. We obser...

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

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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.

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

ITS-2 sequences-based identification of Trichogramma species in South America

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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.

An Initial Meteoroid Stream Survey in the Southern Hemisphere Using the Southern Argentina Agile Meteor Radar (SAAMER)

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Janches, D.; Hormaechea, J. L.; Brunini, C.; Hocking, W.; Fritts, D. C.

2013-01-01

We present in this manuscript a 4 year survey of meteor shower radiants utilizing the Southern Argentina Agile Meteor Radar (SAAMER). SAAMER, which operates at the southern most region of South America, is a new generation SKiYMET system designed with significant differences from typical meteor radars including high transmitted power and an 8-antenna transmitting array enabling large detected rates at low zenith angles. We applied the statistical methodology developed by Jones and Jones (Jones, J., Jones, W. [2006]. Month. Not. R. Astron. Soc. 367, 1050-1056) to the data collected each day and compiled the results into 1 composite representative year at 1 resolution in Solar Longitude. We then search for enhancements in the activity which last for at least 3 days and evolve temporally as is expected from a meteor shower. Using this methodology, we have identified in our data 32 shower radiants, two of which were not part of the IAU commission 22 meteor shower working list. Recently, SAAMER's capabilities were enhanced by adding two remote stations to receive meteor forward scatter signals from meteor trails and thus enable the determination of meteoroid orbital parameters. SAAMER started recording orbits in January 2012 and future surveys will focus on the search for unknown meteor streams, in particular in the southern ecliptic sky.

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

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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.

Agro-fuels: southern impacts; Agrocarburants: impacts au Sud

Energy Technology Data Exchange (ETDEWEB)

Duterme, B.

2011-07-01

At a time of controversies about global warming, agro-fuels production is often presented as a future solution for automotive fuels and as a new way of development for southern countries. However, in Asia, South America and Africa, it very often takes the form of huge mono-culture areas of sugar cane, palm oil and soy bean in the hands of multinational companies of the agriculture and food industry. The consequences of these land, social and environmental impacts in Southern countries is an increase of disequilibria and a threat for the diet of local populations by changing the appropriation of lands. Deforestation, private monopolization of lands, concentration of profits, soils and water pollution, biodiversity impoverishment, exploitation of vulnerable manpower, populations migration, violation of human rights are today the consequences of mass production of agro-fuels in Southern countries. To what conditions a fair re-appropriation and a sustainable development of agro-fuels production and consumption is foreseeable? The solutions require a re-shaping of economical and agricultural politics. The book gathers testimonies and analyses from specialists who have evaluated locally the consequences of these energy choices. (J.S.)

Is increasing industrialization affecting remote ecosystem health in the South Americas? Insights from ocean surface water measurements of As, Sb and Pb from a GEOTRACES transect

Science.gov (United States)

Weiss, Dominik; Salaun, Pascal; Van den Berg, Stan; Bi, Zaoshun

2014-05-01

Continued industrial development of the South Americas with increasing atmospheric emission of toxic trace metals has lead to a growing concern about possible effects on pristine ecosystem health. Concentration measurements of trace metals in ocean surface waters in the North Atlantic have successfully revealed the global extent of atmospheric pollution in the Northern Hemisphere during economical growth in the USA and Europe, suggesting a similar approach can be applied to the Southern Hemisphere. To this end, we determined concentrations of lead (Pb), antimony (Sb) and arsenic (As) using voltammetry in surface water samples of the South Atlantic Ocean collected during the third leg of the GEOTRACES West Atlantic Cruise. These elements are volatile and therefore most likely suitable tracer elements of industrial emissions from South America. The samples were not filtered and the solutions were acidified and UV digested. Total concentrations of Pb were detected. Detected As levels correspond to the sum of inorganic species (AsIII + AsV) plus the mono methyl arsenic acid (MMA) while the dimethyl arsenic acid (DMA) is not detected in such conditions. For Sb, detected levels correspond at least to the sum of inorganic fractions (SbIII + SbV). The measured concentrations for Pb varied from 6 to 23 pM. Concentrations were highest at -35° latitude and lowest at -40° and -50° latitude. We found a decreasing trend from about -35° latitude southwards. The average concentrations of As was 20 nM and of Sb 1.2 nM. Arsenic showed a more significant north to south trend than Sb. Arsenic concentration was highest at -23 ° latitude (21 nM) and the lowest at -43 ° latitude (17.7 nM). Antimony concentration was highest at -31 ° latitude (1.5 nM) and lowest at -35 ° latitude (1.0 nM). Our preliminary data suggests that the major industrial centres in Brazil (i.e., Sao Paolo, Rio de Janeiro) and Argentina (i.e., Buenos Aires) affect atmospheric metal fluxes to remote

Correlations of some Neoproterozoic carbonate-dominated successions in South America based on high-resolution chemostratigraphy

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Alcides Nobrega Sial

Full Text Available ABSTRACT: This report reviews and incorporates new elemental and isotope chemostratigraphic data for correlation of Neoproterozoic carbonate-dominated successions in South America (Argentina, Bolivia, Brazil, Paraguay and Uruguay. These thick mixed carbonate/siliciclastic successions were largely deposited in epicontinental basins or accumulated on passive margins on the edges of cratons (e.g. São Francisco, Amazonia, Rio Apa Block, Pampia and Río de la Plata paleocontinents during extensional events related to the rifting of the Rodinia Supercontinent. From the stratigraphic point of view, these successions occur as three mega-sequences: glaciogenic, marine carbonate platform (above glaciomarine diamictites or rift successions, and dominantly continental to transitional siliciclastics. In the orogenic belts surrounding cratons, carbonate-dominated successions with important volcanoclastic/siliciclastic contribution have been, in most cases, strongly deformed. The precise ages of these successions remain a matter of debate, but recently new paleontological and geochronological data have considerably constrained depositional intervals. Here, we report high-resolution C, O, Sr, and S isotope trends measured in well-preserved sample sets and mainly use Sr and C isotopes in concert with lithostratigraphic/biostratigraphic observations to provide detailed correlations of these successions. The establishing of a high-level and definite chemostratigraphic correlation between Neoproterozoic basins in South America is the main goal of this work.

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...

The trade interchange between Latin America and South Korea: The impact of technological development in the trade integration

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Humberto Merritt Tapia

2010-05-01

Full Text Available Trade relations between Latin America and the Republic of Korea started in the early sixties, but only after the beginning of the new century have become more dynamic, especially for the Asian nation. Behind the Korean export boom is the governmental thrust to science and technology, which has resulted in the production of goods with higher added value. The pattern of trade specialization followed by South Korea has allowed it to become one of the leading exporting nations of high technology goods in the world. On the other hand, Latin American nations have also enjoyed a remarkable growth in exports in the last decade, although their exporting profile contrast with that of Korea because their exports tend to be mainly primary products with low added value and some semi-finished goods . The pattern of specialization in Latin America is explained by its provision of vast natural resources, giving it a comparative advantage in world commodity markets. Unfortunately these advantages have not translated into sustained industrial developments throughout the region. In this context, the purpose of this paper is to illustrate the trade trends between South Korea and Latin America in the last ten years in an attempt to understand the reasons behind the asymmetries in trade flows that have been set in this period. The underlying assumption is that the commercial relationship between both parties depends on the pattern of specialization emerged in recent times and responds to the institutional policies implemented by both South Korea and by Latin American nations. The case of Mexico is highlighted because it is getting historic deficits with the Asian nation.

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'

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

Influence of Surface Processes over Africa on the Atlantic Marine ITCZ and South American Precipitation.

Science.gov (United States)

Hagos, Samson M.; Cook, Kerry H.

2005-12-01

Previous studies show that the climatological precipitation over South America, particularly the Nordeste region, is influenced by the presence of the African continent. Here the influence of African topography and surface wetness on the Atlantic marine ITCZ (AMI) and South American precipitation are investigated.Cross-equatorial flow over the Atlantic Ocean introduced by north south asymmetry in surface conditions over Africa shifts the AMI in the direction of the flow. African topography, for example, introduces an anomalous high over the southern Atlantic Ocean and a low to the north. This results in a northward migration of the AMI and dry conditions over the Nordeste region.The implications of this process on variability are then studied by analyzing the response of the AMI to soil moisture anomalies over tropical Africa. Northerly flow induced by equatorially asymmetric perturbations in soil moisture over northern tropical Africa shifts the AMI southward, increasing the climatological precipitation over northeastern South America. Flow associated with an equatorially symmetric perturbation in soil moisture, however, has a very weak cross-equatorial component and very weak influence on the AMI and South American precipitation. The sensitivity of the AMI to soil moisture perturbations over certain regions of Africa can possibly improve the skill of prediction.

Southern Phosphorus Indices, Water Quality Data, and Modeling (APEX, APLE, and TBET) Results: A Comparison.

Science.gov (United States)

Osmond, Deanna; Bolster, Carl; Sharpley, Andrew; Cabrera, Miguel; Feagley, Sam; Forsberg, Adam; Mitchell, Charles; Mylavarapu, Rao; Oldham, J Larry; Radcliffe, David E; Ramirez-Avila, John J; Storm, Dan E; Walker, Forbes; Zhang, Hailin

2017-11-01

Phosphorus (P) Indices in the southern United States frequently produce different recommendations for similar conditions. We compared risk ratings from 12 southern states (Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Mississippi, North Carolina, Oklahoma, South Carolina, Tennessee, and Texas) using data collected from benchmark sites in the South (Arkansas, Georgia, Mississippi, North Carolina, Oklahoma, and Texas). Phosphorus Index ratings were developed using both measured erosion losses from each benchmark site and Revised Universal Soil Loss Equation 2 predictions; mostly, there was no difference in P Index outcome. The derived loss ratings were then compared with measured P loads at the benchmark sites by using equivalent USDA-NRCS P Index ratings and three water quality models (Annual P Loss Estimator [APLE], Agricultural Policy Environmental eXtender [APEX], and Texas Best Management Practice Evaluation Tool [TBET]). Phosphorus indices were finally compared against each other using USDA-NRCS loss ratings model estimate correspondence with USDA-NRCS loss ratings. Correspondence was 61% for APEX, 48% for APLE, and 52% for TBET, with overall P index correspondence at 55%. Additive P Indices (Alabama and Texas) had the lowest USDA-NRCS loss rating correspondence (31%), while the multiplicative (Arkansas, Florida, Louisiana, Mississippi, South Carolina, and Tennessee) and component (Georgia, Kentucky, and North Carolina) indices had similar USDA-NRCS loss rating correspondence-60 and 64%, respectively. Analysis using Kendall's modified Tau suggested that correlations between measured and calculated P-loss ratings were similar or better for most P Indices than the models. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Multistation digisonde observations of equatorial spread F in South America

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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.

Gallbladder cancer: South American experience.

Science.gov (United States)

Arroyo, Gerardo F; Gentile, Alberto; Parada, Luis A

2016-10-01

Large differences in terms of incidence and mortality due to gallbladder cancer (GBC) have been reported worldwide. Moreover, it seems that GBC has unique characteristics in South America. We surveyed the literature looking for information about the epidemiology, basic and translational research, and clinical trials performed in South America in order to critically analyze the magnitude of this health problem in the region. Compared to other geographic areas, age-standardized mortality rates (ASMR) for GBC in women are very high, particularly in many western areas of South America. Genetic, as well as dietary and environmental factors likely contribute to the pathogenesis of this disease in the area. Compared to other regions the profile of abnormalities of key genes such as KRAS and TP53 in GBC seems to slightly differ in South America, while the clinical behavior appears to be similar with a median overall survival (OS) of 6.5 to 8 months in advanced GBC. In contrast to Europe and USA, prophylactic cholecystectomy is a common practice in western areas of South America. GBC particularly affects women in South America, and represents a significant public health problem. It appears to have peculiarities that pose an urgent need for additional research aimed to discover risk factors, molecular events associated with its development and new treatment options for this lethal disease.

The Araucanian Indian in Chile. IWGIA Document 20.

Science.gov (United States)

Berdichewsky, Bernardo

One of the larger of the native peoples of South America, the Araucanians include different ethnic subgroups, some of which are now extinct. Once geographically spread extensively over the southern cone of South America, at present they are reduced to only two closely related groups: (1) the Mapuche of southern Chile, the largest one; and (2) the…

Precipitation variability in the winter rainfall zone of South Africa during the last 1400 yr linked to the austral westerlies

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J. C. Stager

2012-05-01

Full Text Available The austral westerlies strongly influence precipitation and ocean circulation in the southern temperate zone, with important consequences for cultures and ecosystems. Global climate models anticipate poleward retreat of the austral westerlies with future warming, but the available paleoclimate records that might test these models have been limited to South America and New Zealand, are not fully consistent with each other and may be complicated by influences from other climatic factors. Here we present the first high-resolution diatom and sedimentological records from the winter rainfall region of South Africa, representing precipitation in the equatorward margin of the westerly wind belt during the last 1400 yr. Inferred rainfall was relatively high ∼1400–1200 cal yr BP, decreased until ∼950 cal yr BP, and rose notably through the Little Ice Age with pulses centred on ∼600, 530, 470, 330, 200, 90, and 20 cal yr BP. Synchronous fluctuations in Antarctic ice core chemistry strongly suggest that these variations were linked to changes in the westerlies. Equatorward drift of the westerlies during the wet periods may have influenced Atlantic meridional overturning circulation by restricting marine flow around the tip of Africa. Apparent inconsistencies among some aspects of records from South America, New Zealand and South Africa warn against the simplistic application of single records to the Southern Hemisphere as a whole. Nonetheless, these findings in general do support model projections of increasing aridity in the austral winter rainfall zones with future warming.

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

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

Readings from Asia: Questioning America Again

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Yerim Kim

2013-06-01

Full Text Available Chang Sei-jin. Sangsangdoen America: 1945 nyǒn 8wol ihu Hangukui neisǒn seosanǔn ǒtteoke mandǔleogǒtnǔnga 상상된 아메리카: 1945년 8월 이후 한국의 네이션 서사는 어떻게 만들어졌는가 [Imagined America: How national narratives of Korea have been constructed since August 1945]. Seoul: Purǔn Yeoksa, 2012.Research on U.S.–South Korean relations has continued steadily over the decades, especially in the fields of history and literature, resulting in many notable studies. However, the general tendency of this scholarship has been to introduce and analyze the United States as a discrete entity. While this perspective is useful in some regards, it is also necessary to investigate how this entity was felt, perceived, and constructed by those on the receiving end. By shifting the focus from “what America was in South Korea” to “how America was imagined in South Korea,” Sei-Jin Chang’s Imagined America: How National Narratives of Korea Have Been Constructed since August 1945 provides an insightful approach to this issue of complexity.

Elopomorpha leptocephali from Southern Brazil: a new report of Albula sp. (Albulidae and first record of Elops smithi (Elopidae in Brazilian waters

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Carlos Alberto Santos de Lucena

2012-08-01

Full Text Available http://dx.doi.org/10.5007/2175-7925.2012v25n4p297   Although adult specimens of Albula and Elops have already been captured in the coast of the State of Rio Grande do Sul, Southern Brazil, the occurrence of their larvae leptocepahli is recorded for the first time. Two leptocephali (44.5 and 47.1mm SL of Albula and five (25 to 33mm SL of Elops smithi collected at Tramandai beach, near the estuarine region, are presented. The species E. smithi (known as malacho in its area of occurrence is recorded for the first time in the Brazilian coast, considerably increasing its distribution from northern South America, the Caribbean region, Gulf of Mexico, and along the East Coast of North America to Southern Brazil. It is likely that the records of Elops saurus in Brazil correspond to E. smithi.

A GPS Modeling Study of Earthquakes and Deformation in Northern Central America and along the Middle America Trench: 1999 to 2017

Science.gov (United States)

Ellis, Andria P.

Central America. Doing so was complicated by the occurrence of four M > 7 earthquakes since 2009, which perturbed the velocities of many of the GPS sites. To extract the interseismic velocity field from position time-series, we use TDEFNODE software to simultaneously model source parameters for coseismic rupture and transient afterslip from the 2012 El Salvador (M w = 7.3), 2012 Guatemala (Mw = 7.4), and 2009 Swan Islands (Mw = 7.3) earthquakes. The resulting, corrected best-fitting GPS site velocities are used in my third and final chapter. Finally, I address a variety of questions regarding several major faults that are the root of natural hazard studies in northern Central America. The 200+ site GPS velocity field derived in Chapter 2 far exceeds any previous velocity field for this region and represents a new standard for studying the tectonics of northern Central America. An inversion of the new velocity field using an eight-block elastic model gives the following unique or improved results with respect to previous work: 1) First evidence for a nearly rigid Chortis block south of the Motagua fault; 2) Evidence for southward transfer of slip from the western Motagua fault into the Guatemala City graben and other nearby normal faults; 3) A well-bounded estimate on partitioning of plate boundary slip on the Motagua and Polochic faults; 4) A first plate tectonic estimate of Cocos plate subduction below the Central America forearc sliver; 5) The first geodetic estimate of slip rate variations along the Central America volcanic arc, including the first slip rate estimate for the poorly-understood Jalpatagua fault in southern Guatemala; 6) The first geodetic estimate of distributed deformation in the Chiapas Tectonic Province; 7) Evidence for stronger locking offshore southern Mexico and even weaker shallow locking offshore Guatemala and El Salvador than previously estimated; 8) A refined estimate of how extension is distributed across the grabens of western Honduras and

A Southern Hemisphere atmospheric history of carbon monoxide from South Pole firn air

Science.gov (United States)

Verhulst, K. R.; Aydin, M.; Novelli, P. C.; Holmes, C. D.; Prather, M. J.; Saltzman, E. S.

2013-12-01

Carbon monoxide (CO) is a reactive trace gas and is important to tropospheric photochemistry as a major sink of hydroxyl radicals (OH). Major sources of CO are fossil fuel combustion, linked mostly to automotive emissions, biomass burning, and oxidation of atmospheric methane. Understanding changes in carbon monoxide over the past century will improve our understanding of man's influence on the reactivity of the atmosphere. Little observational information is available about CO levels and emissions prior to the 1990s, particularly for the Southern Hemisphere. The NOAA global flask network provides the most complete instrumental record of CO, extending back to 1988. Annually averaged surface flask measurements suggest atmospheric CO levels at South Pole were relatively stable from 2004-2009 at about 51 nmol mol-1 [Novelli and Masarie, 2013]. In this study, a 20th century atmospheric history of CO is reconstructed from South Pole firn air measurements, using a 1-D firn air diffusion model. Firn air samples were collected in glass flasks from two adjacent holes drilled from the surface to 118 m at South Pole, Antarctica during the 2008/2009 field season and CO analysis was carried out by NOAA/CCG. Carbon monoxide levels increase from about 45 nmol mol-1 in the deepest firn sample at 116 m to 52 nmol mol-1 at 107 m, and remain constant at about 51-52 nmol mol-1 at shallower depths. Atmospheric histories based on the firn air reconstructions suggest that CO levels over Antarctica increased by roughly 40% (from about 36 to 50 nmol mol-1) between 1930-1990, at a rate of about 0.18 nmol mol-1 yr-1. Firn air and surface air results suggest the rate of CO increase at South Pole slowed considerably after 1990. The firn air-based atmospheric history is used to infer changes in Southern Hemisphere CO emissions over the 20th century.

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

Region: South Asia, North of Sahara, South of Sahara, North and Central America, South America, Central Asia, Far East Asia, Bangladesh, South Africa. Program: Think Tank Initiative. Total Funding: CA$ 692,000.00. Southern Voice on Post-Millennium Development Goals. Project. As 2015 approaches, the international ...

The southern cape conductive belt (South Africa): Its composition, origin and tectonic significance

Science.gov (United States)

De Beer, J. H.; Van Zijl, J. S. V.; Gough, D. I.

1982-03-01

Magnetometer array studies have led to the discovery and mapping of the Southern Cape Conductive Belt (SCCB) crossing the southern tip of Africa from west to southeast coasts. The SCCB lies just south of the Namaqua-Natal Belt of cratonic rocks remobilized about 1000 m.y. B.P. It is shown that it coincides with a zone of weakness which has been exploited by three major geosynclinal accumulations over some 600 m.y. Relationships between the SCCB and the basement geochronology, geology and tectonics are considered in detail. These relationships support the view that the conductive belt was formed by an accumulation of marine sediments and oceanic lithosphere at the top of a Proterozoic subduction which stopped about 1000 to 800 m.y. B.P. Associated with this subduction we propose a Proterozoic range of Andean mountains, whose roots are now exposed in the Namaqua-Natal Belt. Later subduction further south, near the present south coast, is proposed to account for the intrusion, between the south coast and the SCCB, of the Cape Granites in the time interval 600-500 m.y. B.P. There is some evidence for a third, yet more distant, subduction episode off Permian Gondwanaland. After outlining this tectonic history, the paper turns to a closer examination of the hypothesis that the Southern Cape Conductive Belt consists of partly serpentinized basalt accumulated at the top of a Proterozoic subduction. A large static magnetic anomaly, which correlates with the SCCB over most of its length, is well fitted by a model which strongly supports this hypothesis. Bouguer gravity anomalies along western and central profiles likewise support the hypothesis. A discussion follows of the process of formation of the proposed block of serpentinized marine rocks, beginning with serpentinization of the crust near oceanic ridges by reaction of warm, porous, newly-extruded basalt with seawater convecting through it. The serpentinized basalt is stable at crustal temperatures and pressures and so

Analysis of tropospheric ozone and carbon monoxide profiles over South America based on MOZAIC/IAGOS database and model simulations

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Marcia A. Yamasoe

2015-10-01

Full Text Available We analysed ozone and carbon monoxide profiles measured by commercial aircrafts from the MOZAIC/IAGOS fleet, during ascending and descending flights over Caracas, in Venezuela, from August 1994 to December 2009, over Rio de Janeiro, from 1994 to 2004 and from July 2012 to June 2013, and over São Paulo, in Brazil, from August 1994 to 2005. For ozone, results showed a clean atmosphere over Caracas presenting the highest seasonal mean in March, April and May. Backward trajectory analyses with FLEXPART, of case studies for which the measured concentrations were high, showed that contributions from local, Central and North America, the Caribbean and Africa either from anthropogenic emissions, biomass burning or lightning were possible. Satellite products as fire counts from MODIS, lightning flash rates from LIS, and CO and O3 from Infrared Atmospheric Sounding Interferometer and wind maps at different levels helped corroborate previous findings. Sensitivity studies performed with the chemical transport model GEOS-Chem captured the effect of anthropogenic emissions but underestimated the influence of biomass burning, which could be due to an underestimation of GFEDv2 emission inventory. The model detected the contribution of lightning from Africa in JJA and SON and from South America in DJF, possibly from the northeast of Brazil. Over São Paulo and Rio de Janeiro, GEOS-Chem captured the seasonal variability of lightning produced in South America and attributed this source as the most important in this region, except in JJA, when anthropogenic emissions were addressed as the more impacting source of ozone precursors. However, comparison with the measurements indicated that the model overestimated ozone formation, which could be due to the convective parameterisation or the stratospheric influence. The highest ozone concentration was observed during September to November, but the model attributed only a small influence of biomass burning from South

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

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

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)

[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.

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...

Predicting Pleistocene climate from vegetation in North America

Directory of Open Access Journals (Sweden)

C. Loehle

2007-01-01

Full Text Available Climates at the Last Glacial Maximum have been inferred from fossil pollen assemblages, but these inferred climates are colder for eastern North America than those produced by climate simulations. It has been suggested that low CO2 levels could account for this discrepancy. In this study biogeographic evidence is used to test the CO2 effect model. The recolonization of glaciated zones in eastern North America following the last ice age produced distinct biogeographic patterns. It has been assumed that a wide zone south of the ice was tundra or boreal parkland (Boreal-Parkland Zone or BPZ, which would have been recolonized from southern refugia as the ice melted, but the patterns in this zone differ from those in the glaciated zone, which creates a major biogeographic anomaly. In the glacial zone, there are few endemics but in the BPZ there are many across multiple taxa. In the glacial zone, there are the expected gradients of genetic diversity with distance from the ice-free zone, but no evidence of this is found in the BPZ. Many races and related species exist in the BPZ which would have merged or hybridized if confined to the same refugia. Evidence for distinct southern refugia for most temperate species is lacking. Extinctions of temperate flora were rare. The interpretation of spruce as a boreal climate indicator may be mistaken over much of the region if the spruce was actually an extinct temperate species. All of these anomalies call into question the concept that climates in the zone south of the ice were extremely cold or that temperate species had to migrate far to the south. An alternate hypothesis is that low CO2 levels gave an advantage to pine and spruce, which are the dominant trees in the BPZ, and to herbaceous species over trees, which also fits the observed pattern. Thus climate reconstruction from pollen data is probably biased and needs to incorporate CO2 effects. Most temperate species could have survived across their current

Tides and Their Dynamics over the Sunda Shelf of the Southern South China Sea.

Science.gov (United States)

Daryabor, Farshid; Ooi, See Hai; Abu Samah, Azizan; Akbari, Abolghasem

2016-01-01

A three-dimensional Regional Ocean Modelling System is used to study the tidal characteristics and their dynamics in the Sunda Shelf of the southern South China Sea. In this model, the outer domain is set with a 25 km resolution and the inner one, with a 9 km resolution. Calculations are performed on the inner domain. The model is forced at the sea surface by climatological monthly mean wind stress, freshwater (evaporation minus precipitation), and heat fluxes. Momentum and tracers (such as temperature and salinity) are prescribed in addition to the tidal heights and currents extracted from the Oregon State University TOPEX/Poseidon Global Inverse Solution (TPXO7.2) at the open boundaries. The results are validated against observed tidal amplitudes and phases at 19 locations. Results show that the mean average power energy spectrum (in unit m2/s/cph) for diurnal tides at the southern end of the East Coast of Peninsular Malaysia is approximately 43% greater than that in the East Malaysia region located in northern Borneo. In contrast, for the region of northern Borneo the semidiurnal power energy spectrum is approximately 25% greater than that in the East Coast of Peninsular Malaysia. This implies that diurnal tides are dominant along the East Coast of Peninsular Malaysia while both diurnal and semidiurnal tides dominate almost equally in coastal East Malaysia. Furthermore, the diurnal tidal energy flux is found to be 60% greater than that of the semidiurnal tides in the southern South China Sea. Based on these model analyses, the significant tidal mixing frontal areas are located primarily off Sarawak coast as indicated by high chlorophyll-a concentrations in the area.

Regeneration patterns of a long-lived dominant conifer and the effects of logging in southern South America

Science.gov (United States)

Souza, Alexandre F.; Forgiarini, Cristiane; Longhi, Solon Jonas; Brena, Doádi Antônio

2008-09-01

The regeneration ecology of the long-lived conifer Araucaria angustifolia was studied in São Francisco de Paula, southern Brazil. We evaluated the expectations that: (i) size distribution of populations of Araucaria angustifolia, a large conifer that dominates southern Brazil's mixed forests, is left-skewed in old-growth forests but right-skewed in logged forests, indicating chronic recruitment failure in the first kind of habitat as well as a recruitment pulse in the second; (ii) seedlings and juveniles are found under more open-canopy microsites than would be expected by chance; and (iii) reproductive females would be aggregated at the coarse spatial scales in which past massive recruitment events are expected to have occurred, and young plants would be spatially associated with females due to the prevalence of vertebrate and large-bird seed dispersers. Data were collected in the threatened mixed conifer-hardwood forests in southern Brazil in ten 1-ha plots and one 0.25-ha plot that was hit by a small tornado in 2003. Five of these plots corresponded to unlogged old-growth forests, three to forests where A. angustifolia was selectively logged ca. 60 years ago and two to forests selectively logged ca. 20 years ago. For the first time, ontogenetic life stages of this important conifer are identified and described. The first and second expectations were fulfilled, and the third was partially fulfilled, since seedlings and juveniles were hardly ever associated with reproductive females. These results confirm the generalization of the current conceptual model of emergent long-lived pioneer regeneration to Araucaria angustifolia and associate its regeneration niche to the occupation of large-scale disturbances with long return times.

Weather regimes in the South American sector and neighbouring oceans during winter

Energy Technology Data Exchange (ETDEWEB)

Solman, S.A.; Menendez, C.G. [Centro de Investigaciones del Mar y la Atmosfera (CIMA-CONICET/UBA), Ciudad Universitaria, Buenos Aires (Argentina)

2003-07-01

We classified 34 years of winter daily 500 hPa geopotential height patterns over the eastern South Pacific-South America-South Atlantic region using the K-means clustering method. We found a significant classification into five weather regimes (WRs) defined as the most frequent large-scale circulation anomalies: WR1 (trough centred downstream of the Drake Passage), WR2 (trough over the SW Pacific and ridge downstream), WR3 (ridge over the SE Pacific and NW-SE trough downstream), WR4 (trough over the SE Pacific and NW-SE ridge downstream) and WR5 (weak ridge to the west of southern South America). We also analysed their persistence and temporal evolution, including transitions between them and development around onsets and breaks of each regime. The preferred transitions, WR1{yields}WR3{yields}WR2{yields}WR4{yields}WR1 and also WR1{yields}WR3{yields}WR2{yields}WR1, suggest the progression of a Rossby wave-like pattern in which each of the regimes resemble the Pacific-South America modes. Significant influence of the WRs on local climate over Argentina was found. The preferred transitions WR1{yields}WR3 and WR3{yields}WR2 induce sustained cold conditions over Patagonia and over northern Argentina, respectively. The most significant change in precipitation frequency is found for WR3, with wetter conditions over all the analysed regions. Finally, the interannual to interdecadal significant variations in the occurrence of these regimes were discussed. WR1 and WR3 are more frequent and WR2 is less frequent during El Nino, and WR2 and WR5 are more frequent and WR1 is less frequent during La Nina. A significant decrease in WR2 and increase of WR4 and WR5 during the 1970s and early 1980s were found. (orig.)

Trend and recovery of the total ozone column in South America and Antarctica

Science.gov (United States)

Toro A., Richard; Araya, Consuelo; Labra O., Felipe; Morales, Luis; Morales, Raúl G. E.; Leiva G., Manuel A.

2017-12-01

South America is one of the most vulnerable areas to stratospheric ozone depletion; consequently, an increased amount of UV radiation reaches the Earth's surface in this region. In this study, we analyzed the long-term trend in the total ozone column (TOC) over the southern part of the South American continent from 1980 to 2009. The database used was obtained by combining several satellite measurements of the TOC on a 1° (latitude) × 1.25° (longitude) grid. Analysis of the long-term trend was performed by applying the Theil-Sen estimator and the Mann-Kendall significance test to the deseasonalized time series. The long-term trend was also analyzed over several highly populated urban zones in the study area. Finally, multiple linear regression (MLR) modeling was used to identify and quantify the drivers of interannual variability in the TOC over the study area with a pixel-by-pixel approach. The results showed a decrease in the TOC ranging from -0.3 to -4% dec-1 from 1980 to 2009. On a decadal timescale, there is significant variability in this trend, and a decrease of more than -10% dec-1 was found at high latitudes (1980-1989). However, the trends obtained over much of the study area were not statistically significant. Considering the period from 1980 to 1995, we found a decrease in the TOC of -2.0 ± 0.6% dec-1 at latitudes below 40° S and -6.9 ± 2.0% dec-1 at latitudes above 40° S, for a 99.9% confidence level over most of the study area. Analysis of the period from 1996 to 2009 showed a statistically significant increase of 2.3 ± 0.1% dec-1 at high latitudes (> 60° S), confirming the initial TOC recovery in the Antarctic. Despite evidence for initial recovery of the TOC in some parts of the study area between 1996 and 2009, the long-term increase from September to November is not yet statistically significant. In addition, large parts of the study area and most of the urban areas continue to show a decreasing trend in the TOC. The MLR results show that

HIV-1 subtype F1 epidemiological networks among Italian heterosexual males are associated with introduction events from South America.

Science.gov (United States)

Lai, Alessia; Simonetti, Francesco R; Zehender, Gianguglielmo; De Luca, Andrea; Micheli, Valeria; Meraviglia, Paola; Corsi, Paola; Bagnarelli, Patrizia; Almi, Paolo; Zoncada, Alessia; Paolucci, Stefania; Gonnelli, Angela; Colao, Grazia; Tacconi, Danilo; Franzetti, Marco; Ciccozzi, Massimo; Zazzi, Maurizio; Balotta, Claudia

2012-01-01

About 40% of the Italian HIV-1 epidemic due to non-B variants is sustained by F1 clade, which circulates at high prevalence in South America and Eastern Europe. Aim of this study was to define clade F1 origin, population dynamics and epidemiological networks through phylogenetic approaches. We analyzed pol sequences of 343 patients carrying F1 subtype stored in the ARCA database from 1998 to 2009. Citizenship of patients was as follows: 72.6% Italians, 9.3% South Americans and 7.3% Rumanians. Heterosexuals, Homo-bisexuals, Intravenous Drug Users accounted for 58.1%, 24.0% and 8.8% of patients, respectively. Phylogenetic analysis indicated that 70% of sequences clustered in 27 transmission networks. Two distinct groups were identified; the first clade, encompassing 56 sequences, included all Rumanian patients. The second group involved the remaining clusters and included 10 South American Homo-bisexuals in 9 distinct clusters. Heterosexual modality of infection was significantly associated with the probability to be detected in transmission networks. Heterosexuals were prevalent either among Italians (67.2%) or Rumanians (50%); by contrast, Homo-bisexuals accounted for 71.4% of South Americans. Among patients with resistant strains the proportion of clustering sequences was 57.1%, involving 14 clusters (51.8%). Resistance in clusters tended to be higher in South Americans (28.6%) compared to Italian (17.7%) and Rumanian patients (14.3%). A striking proportion of epidemiological networks could be identified in heterosexuals carrying F1 subtype residing in Italy. Italian Heterosexual males predominated within epidemiological clusters while foreign patients were mainly Heterosexual Rumanians, both males and females, and South American Homo-bisexuals. Tree topology suggested that F1 variant from South America gave rise to the Italian F1 epidemic through multiple introduction events. The contact tracing also revealed an unexpected burden of resistance in epidemiological

A tropospheric ozone maximum over the equatorial Southern Indian Ocean

Directory of Open Access Journals (Sweden)

L. Zhang

2012-05-01

Full Text Available We examine the distribution of tropical tropospheric ozone (O₃ from the Microwave Limb Sounder (MLS and the Tropospheric Emission Spectrometer (TES by using a global three-dimensional model of tropospheric chemistry (GEOS-Chem. MLS and TES observations of tropospheric O₃ during 2005 to 2009 reveal a distinct, persistent O₃ maximum, both in mixing ratio and tropospheric column, in May over the Equatorial Southern Indian Ocean (ESIO. The maximum is most pronounced in 2006 and 2008 and less evident in the other three years. This feature is also consistent with the total column O₃ observations from the Ozone Mapping Instrument (OMI and the Atmospheric Infrared Sounder (AIRS. Model results reproduce the observed May O₃ maximum and the associated interannual variability. The origin of the maximum reflects a complex interplay of chemical and dynamic factors. The O₃ maximum is dominated by the O₃ production driven by lightning nitrogen oxides (NO_x emissions, which accounts for 62% of the tropospheric column O₃ in May 2006. We find the contribution from biomass burning, soil, anthropogenic and biogenic sources to the O₃ maximum are rather small. The O₃ productions in the lightning outflow from Central Africa and South America both peak in May and are directly responsible for the O₃ maximum over the western ESIO. The lightning outflow from Equatorial Asia dominates over the eastern ESIO. The interannual variability of the O₃ maximum is driven largely by the anomalous anti-cyclones over the southern Indian Ocean in May 2006 and 2008. The lightning outflow from Central Africa and South America is effectively entrained by the anti-cyclones followed by northward transport to the ESIO.

American Trypanosomiasis (Also Known as Chagas Disease) Triatomine Bug FAQs

Science.gov (United States)

... are typically found in the southern United States, Mexico, Central America, and South America (as far south ... feed on the blood of mammals (including humans), birds, and reptiles. Triatomine bugs live in a wide ...

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

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.

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

75 FR 20390 - Robert Bosch LLC, Including On-Site Leased Workers From Bosch Management Services North America...

Science.gov (United States)

2010-04-19

...-site leased workers of Bosch Management Services North America, South Haven Community Hospital... leased workers of Bosch Management Services North America, South Haven Community Hospital, Huffmaster Inc..., Including On-Site Leased Workers From Bosch Management Services North America, South Haven Community...

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)

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.

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.

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.

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).

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...

The OECD-BEPS Measures to Deal with Aggressive Tax Planning in South America and Sub-Saharan Africa : The Challenges Ahead

NARCIS (Netherlands)

Mosquera, Valderrama I.J.

2015-01-01

The aim of this article is to assess the feasibility to introduce the Organisation for Economic Co-operation and Development (OECD)-BEPS measures to deal with aggressive tax planning in South America and Sub-Saharan Africa. The BEPS and its Action Plan have been developed by the OECD following

Draft genome sequence of pathogenic bacteria Vibrio parahaemolyticus strain Ba94C2, associated with acute hepatopancreatic necrosis disease isolate from South America

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Leda Restrepo

2016-09-01

Full Text Available Vibrio parahaemolyticus is a pathogenic bacteria which has been associated to the early mortality syndrome (EMS also known as hepatopancreatic necrosis disease (AHPND causing high mortality in shrimp farms. Pathogenic strains contain two homologous genes related to insecticidal toxin genes, PirA and PirB, these toxin genes are located on a plasmid contained within the bacteria. Genomic sequences have allowed the finding of two strains with a divergent structure related to the geographic region from where they were found. The isolates from the geographic collection of Southeast Asia and Mexico show variable regions on the plasmid genome, indicating that even though they are not alike they still conserve the toxin genes. In this paper, we report for the first time, a pathogenic V. parahaemolyticus strain in shrimp from South America that showed symptoms of AHPND. The genomic analysis revealed that this strain of V. parahaemolyticus found in South America appears to be more related to the Southeast Asia as compared to the Mexican strains. This finding is of major importance for the shrimp industry, especially in regards to the urgent need for disease control strategies to avoid large EMS outbreaks and economic loss, and to determine its dispersion in South America. The whole-genome shotgun project of V. parahaemolyticus strain Ba94C2 have been deposited at DDBJ/EMBL/GenBank under the accession PRJNA335761.

Tides and their dynamics over the Sunda Shelf of the southern South China Sea

DEFF Research Database (Denmark)

Daryabor, Farshid; Ooi, See Hai Ooi; Samah, Azizan Abu

2016-01-01

A three-dimensional Regional Ocean Modelling System is used to study the tidal characteristics and their dynamics in the Sunda Shelf of the southern South China Sea. In this model, the outer domain is set with a 25 km resolution and the inner one, with a 9 km resolution. Calculations are performe...... on these model analyses, the significant tidal mixing frontal areas are located primarily off Sarawak coast as indicated by high chlorophyll-a concentrations in the area....

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.

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.

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)

Differential Susceptibilities of Aedes aegypti and Aedes albopictus from the Americas to Zika Virus.

Directory of Open Access Journals (Sweden)

Thais Chouin-Carneiro

2016-03-01

Full Text Available Since the major outbreak in 2007 in the Yap Island, Zika virus (ZIKV causing dengue-like syndromes has affected multiple islands of the South Pacific region. In May 2015, the virus was detected in Brazil and then spread through South and Central America. In December 2015, ZIKV was detected in French Guiana and Martinique. The aim of the study was to evaluate the vector competence of the mosquito spp. Aedes aegypti and Aedes albopictus from the Caribbean (Martinique, Guadeloupe, North America (southern United States, South America (Brazil, French Guiana for the currently circulating Asian genotype of ZIKV isolated from a patient in April 2014 in New Caledonia.Mosquitoes were orally exposed to an Asian genotype of ZIKV (NC-2014-5132. Upon exposure, engorged mosquitoes were maintained at 28° ± 1 °C, a 16h:8h light:dark cycle and 80% humidity. 25-30 mosquitoes were processed at 4, 7 and 14 days post-infection (dpi. Mosquito bodies (thorax and abdomen, heads and saliva were analyzed to measure infection, dissemination and transmission, respectively. High infection but lower disseminated infection and transmission rates were observed for both Ae. aegypti and Ae. albopictus. Ae. aegypti populations from Guadeloupe and French Guiana exhibited a higher dissemination of ZIKV than the other Ae. aegypti populations examined. Transmission of ZIKV was observed in both mosquito species at 14 dpi but at a low level.This study suggests that although susceptible to infection, Ae. aegypti and Ae. albopictus were unexpectedly low competent vectors for ZIKV. This may suggest that other factors such as the large naïve population for ZIKV and the high densities of human-biting mosquitoes contribute to the rapid spread of ZIKV during the current outbreak.

Southern Pine Beetle Information System (SPBIS)

Science.gov (United States)

Valli Peacher

2011-01-01

The southern pine beetle (SPB) is the most destructive forest insect in the South. The SPB attacks all species of southern pine, but loblolly and shortleaf are most susceptible. The Southern Pine Beetle Information System (SPBIS) is the computerized database used by the national forests in the Southern Region for tracking individual southern pine beetle infestations....

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.

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

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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.

Myth and catastrophic reality: using cosmogonic mythology to identify cosmic impacts and massive plinian eruptions in holocene South America.

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Masse, W. B. (William Bruce)

2004-01-01

Major natural catastrophes (e.g., 'universal' floods, fire, darkness, and sky falling down) are prominently reflected in traditional South American creation myths, cosmology, religion, and worldview. We are now beginning to recognize that cosmogonic myths represent a rich and largely untapped data set concerning the most dramatic natural events and processes experienced by each cultural group during the past several thousand years. Observational details regarding specific catastrophes are encoded in myth storylines, typically cast in terms of supernatural characters and actions. Not only are the myths amenable to scientific analysis, but also some sets of myths encode multiple catastrophes in meaningful relative chronological order. The present study considers more than 4200 myths, including more than 260 'universal' catastrophe myths from cultural groups throughout South America. These myths are examined in light of available geological, paleoenvironmental, archeological, and documentary evidence. Our analysis reveals three possible ultra-plinian volcanic eruptions, two in Columbia and the other in the Gran Chaco, the latter likely associated with a poorly dated late Holocene eruption of Nuevo Mundo in central Bolivia. Our analysis also identifies a set of traditions likely linked with the well-known Campo del Cielo iron meteorite impact in northern Argentina originally hypothesized to have occurred around 4000 years ago. Intriguingly, these traditions strongly suggest that the Campo del Cielo impact triggered widespread mass fires in the Gran Chaco region and possibly in the Brazilian Highlands. Several other potential cosmic impacts, distinct from Campo del Cielo, are hinted at in the mythology of other locations in South America. The numerous catastrophe myths in the Gran Chaco region exhibit the most coherent chronological sequence of any South American region. The sequence begins with a 'Great Flood,' by far the most widespread

Climate-biomes, pedo-biomes and pyro-biomes: which world view explains the tropical forest - savanna boundary in South America?

Science.gov (United States)

Langan, Liam; Higgins, Steven; Scheiter, Simon

2015-04-01

Elucidating the drivers of broad vegetation formations improves our understanding of earth system functioning. The biome, defined primarily by the dominance of a particular growth strategy, is commonly employed to group vegetation into similar units. Predicting tropical forest and savanna biome boundaries in South America has proven difficult. Process based DGVMs (Dynamic global vegetation models) are our best tool to simulate vegetation patterns, make predictions for future changes and test theory, however, many DGVMs fail to accurately simulate the spatial distribution or indeed presence of the South American savanna biome which can result in large differences in modelled ecosystem structural properties. Evidence suggests fire plays a significant role in mediating these forest and savanna biome boundaries, however, fire alone does not appear to be sufficient to predict these boundaries in South America using DGVMs hinting at the presence of one or more missing environmental factors. We hypothesise that soil depth, which affects plant available water by determining maximum storage potential and influences temporal availability, may be one of these missing environmental factors. To test our hypothesis we use a novel vegetation model, the aDGVM2. This model has been specifically designed to allow plant trait strategies, constrained by trade-offs between traits, evolve based on the abiotic and biotic conditions where the resulting community trait suites are emergent properties of model dynamics. Furthermore it considers root biomass in multiple soil layers and therefore allows the consideration of alternative rooting strategies, which in turn allows us to explore in more detail the role of soil hydraulic factors in controlling biome boundary distributions. We find that changes in soil depth, interacting with fire, affect the relative dominance of tree and grass strategies and thus the presence and spatial distribution of forest and savanna biomes in South America

Evaluating uncertainties in regional climate simulations over South America at the seasonal scale

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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.)

South Africa : tous les projets | Page 3 | CRDI - Centre de ...

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

Sujet: INTERNATIONAL FINANCE, INTERNATIONAL FINANCIAL MARKET, FINANCIAL POLICY, DEMOGRAPHY, DEMOGRAPHIC CHANGE, DEMOGRAPHIC TRANSITION. Région: Americas, Brazil, South America, Asia, China, Far East Asia, India, South and Central Asia, Global, Africa, South Africa, South of Sahara.

The Arrival of Homo sapiens into the Southern Cone at 14,000 Years Ago.

Science.gov (United States)

Politis, Gustavo G; Gutiérrez, María A; Rafuse, Daniel J; Blasi, Adriana

The Arroyo Seco 2 site contains a rich archaeological record, exceptional for South America, to explain the expansion of Homo sapiens into the Americas and their interaction with extinct Pleistocene mammals. The following paper provides a detailed overview of material remains found in the earliest cultural episodes at this multi-component site, dated between ca. 12,170 14C yrs B.P. (ca. 14,064 cal yrs B.P.) and 11,180 14C yrs B.P. (ca. 13,068 cal yrs B.P.). Evidence of early occupations includes the presence of lithic tools, a concentration of Pleistocene species remains, human-induced fractured animal bones, and a selection of skeletal parts of extinct fauna. The occurrence of hunter-gatherers in the Southern Cone at ca. 14,000 cal yrs B.P. is added to the growing list of American sites that indicate a human occupation earlier than the Clovis dispersal episode, but posterior to the onset of the deglaciation of the Last Glacial Maximum (LGM) in the North America.

The Arrival of Homo sapiens into the Southern Cone at 14,000 Years Ago.

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Gustavo G Politis

Full Text Available The Arroyo Seco 2 site contains a rich archaeological record, exceptional for South America, to explain the expansion of Homo sapiens into the Americas and their interaction with extinct Pleistocene mammals. The following paper provides a detailed overview of material remains found in the earliest cultural episodes at this multi-component site, dated between ca. 12,170 14C yrs B.P. (ca. 14,064 cal yrs B.P. and 11,180 14C yrs B.P. (ca. 13,068 cal yrs B.P.. Evidence of early occupations includes the presence of lithic tools, a concentration of Pleistocene species remains, human-induced fractured animal bones, and a selection of skeletal parts of extinct fauna. The occurrence of hunter-gatherers in the Southern Cone at ca. 14,000 cal yrs B.P. is added to the growing list of American sites that indicate a human occupation earlier than the Clovis dispersal episode, but posterior to the onset of the deglaciation of the Last Glacial Maximum (LGM in the North America.

Rock art at the pleistocene/holocene boundary in Eastern South America.

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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.

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

Are we filling the data void? An assessment of the amount and extent of plant collection records and census data available for tropical South America.

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Kenneth Feeley

Full Text Available Large-scale studies are needed to increase our understanding of how large-scale conservation threats, such as climate change and deforestation, are impacting diverse tropical ecosystems. These types of studies rely fundamentally on access to extensive and representative datasets (i.e., "big data". In this study, I asses the availability of plant species occurrence records through the Global Biodiversity Information Facility (GBIF and the distribution of networked vegetation census plots in tropical South America. I analyze how the amount of available data has changed through time and the consequent changes in taxonomic, spatial, habitat, and climatic representativeness. I show that there are large and growing amounts of data available for tropical South America. Specifically, there are almost 2,000,000 unique geo-referenced collection records representing more than 50,000 species of plants in tropical South America and over 1,500 census plots. However, there is still a gaping "data void" such that many species and many habitats remain so poorly represented in either of the databases as to be functionally invisible for most studies. It is important that we support efforts to increase the availability of data, and the representativeness of these data, so that we can better predict and mitigate the impacts of anthropogenic disturbances.

Nacellidae limpets of the southern end of South America: taxonomy and distribution Lapas Nacellidae del extremo sur de Sudamérica: taxonomía y distribución

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CLAUDIO VALDOVINOS

2005-09-01

Full Text Available Taxonomically, the Mollusca of the southern end of South America are moderately well known, but the literature is scattered, there is little information on their habitats, and distributional records are scarce for the Chilean archipelago lying between Chiloé Island (42° S and Tierra del Fuego (55° S. Although much is known about the biology and ecology of of some species of Nacellidae, the taxonomy of the group have been partially neglected, particularly in remote areas of the world such as the Chilean fjords. Therefore, this study aims to clarify the nomenclatural status, and establish the morphological characteristics and distribution of the Chilean Nacellidae. Especially, the following three objectives are pursued: (i to clarify the correct identity of existing species; (ii to describe of morphological details, highlighting the clear diagnostic characters of each species, and (iii to delimitate and discuss their geographical range in Chile. The examination of the Nacellidae of the Chilean fiords has resulted in the recognition of one species of Nacella (Nacella and seven species of Nacella (Patinigera, wherein the principal specific differences are in the shell (shape, thickness and color and in radular teeth morphology. The genus Nacella and its subgenus Patinigera are cold-water limpets, and are exclusively inhabitants of Subantarctic and Antarctic waters. The greater part of their range being subantarctic, but extending to the Antarctic by way of the Scotia Arc, and also ranging northward up the Chilean coast to at least Valparaiso at 33° S (only N. (P. clypeater. They apparently have their centre of distribution in the Magellanic Province of southern South America, corresponding to an area with a high degree of diversification (N. (N. mytilina, N. (P. chiloensis, N. (P. deaurata, N. (P. delicatissima, N. (P. flammea, N. (P. magellanica, N. (P. venosa, wherefrom the species tends to spread eastward, with a larval transport probably

Detection of non-natural springtime precipitation change over northern South America

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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

Digenetic trematodes in South American sea lions from southern Brazilian waters.

Science.gov (United States)

Pereira, E M; Müller, G; Secchi, E; Pereira, J; Valente, A L S

2013-10-01

The aim of this work was to perform a systematic study to detect and quantify the digenetic trematode infections in South American sea lions from the southern Brazilian coast. Twenty-four South American sea lions, Otaria flavescens (Carnivora: Otaridae), were found dead along the coast of Rio Grande do Sul State, Brazil, between June 2010 and September of 2011. Two trematode species were found in the intestines of O. flavescens, i.e., Stephanoprora uruguayense (Digenea: Echinostomatidae) and Ascocotyle (Phagicola) longa (Digenea: Heterophyidae). Ascocotyle (P.) longa reached a prevalence of 33.3% and mean intensity of 248,500, whereas S. uruguayense showed a prevalence of 4.2% and mean intensity of 202. The 2 trematode species infecting sea lions were likely transmitted by feeding on mullets, Mugil platanus, that commonly harbor heterophyid metacercariae. The present work is the first report of digenetic trematodes infecting O. flavescens in Brazil. The high prevalence and mean intensity values of the 2 trematode species infecting sea lions in the present study suggest caution in human consumption of mullets and other fish, which can be infected with the metacercariae of these trematodes known to have zoonotic potential.

A new species of Trachytherus (Notoungulata: Mesotheriidae) from the late Oligocene (Deseadan) of Southern Peru and the middle latitude diversification of early diverging mesotheriids.

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Shockey, Bruce J; Billet, Guillaume; Salas-Gismondi, Rodolfo

2016-05-18

Herein we describe a new species of early diverging mesotheriid notoungulate from the late Oligocene of Moquegua, Peru. This taxon, Trachytherus ramirezi sp. nov., is distinctive in terms of a few characteristics that appear plesiomorphic as compared to those of other described mesotheriids, even other species referred to Trachytherus. Such plesiomorphic traits include the absence of an upper diastema and a lack of heart-shaped incisive foramina, traits that are generally present in other mesotheriids. Our phylogenetic analysis of described early divergent mesotheriids indicates that T. ramirezi was the earliest to diverge. This analysis also confirms the paraphyletic nature of the "genus" Trachytherus.          Geographically, T. ramirezi clusters among T. alloxus, T. subandinus, and T. spegazzinianus, all of which are known from a discrete region in the middle latitudes of western South America that we refer to as the Bolivian Orocline Region (BOR). Our palaeobiogeographic reconstruction using maximum parsimony identifies the BOR as a possible ancestral area for the Mesotheriidae and as an important region for their diversification. For the more exclusive Mesotheriinae, the BOR was reconstructed as the ancestral area, an area from which some mesotheriines would have later dispersed to southern South America. Uncertainty concerning the ancestral area, for the Mesotheriidae-which could be BOR or southern South America area (or both)-is possibly due to the ignorance of the phylogenetic affinities for the undescribed mesotheriid remains reported from Tinguirirican localities. The present description of T. ramirezi therefore adds to the high taxonomic diversity of early mesotheriid species in the relatively small area of the BOR and emphasizes the likely role played by this topographically dynamic area on mesotheriid evolution during a significant time in the history of the clade.

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Results 331 - 340 of 875 ... Home; South America ... South Asia 1368 Apply South Asia filter · Far East Asia 1311 Apply Far .... Energy-water nexus in the context of climate change in developing ... from Latin America, East and Southern Africa; synthesis report. Decentralized renewable energy technologies can help address ...

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.

Resource selection for foraging by female Merriam's wild turkeys with poults in the southern Black Hills, South Dakota

Science.gov (United States)

Chad P. Lehman; Mark A. Rumble; Lester D. Flake; Daniel J. Thompson

2011-01-01

Knowledge of Merriam's wild turkey (Meleagris gallopavo merriami) resource selection in the context of landscape attributes is an important asset for managing resources on multiple-use public lands. We investigated resource selection for foraging by Merriam's wild turkey broods in the southern Black Hills, South Dakota. We collected macro- and microhabitat...

The influence of socioeconomic factors on the conservation of traditional knowledge: a cross scale comparison of palm use in Northwestern South America

DEFF Research Database (Denmark)

Paniagua-Zambrana, Narel; Cámara-Leret, Rodrigo; Bussmann, Rainer W.

2014-01-01

We explored the power of 14 socioeconomic factors for predicting differences in traditional knowledge about palms (Arecaceae) at the personal, household, and regional levels in 25 locations in the Amazon, Andes, and Chocó of northwestern South America. Using semistructured interviews, we gathered...

Discovery of the first telemid spider (Araneae, Telemidae) from South America, and the first member of the family bearing a stridulatory organ.

Science.gov (United States)

Dupérré, Nadine; Tapia, Elicio

2015-09-21

The genus Kinku n. gen. is established for the first telemid spider found in South America. The new species, Kinku turumanya n. sp. is characterized by the unique conformation of the male palp and the presence of an abdominal anterioventral stridulatory organ.

Feeding ecology of the freshwater crab Trichodactylus borellianus (Decapoda: Trichodactylidae in the floodplain of the Paraná River, southern South America

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Verónica Williner

2013-09-01

Full Text Available Freshwater crabs are not commonly considered to be an important group in trophic webs, and this might be due to a lack of knowledge about their trophic roles in aquatic ecosystems. Trichodactylus borellianus is one of the most common and widely distributed freshwater crabs in the floodplains of the southern South American rivers. The main objective of the present study was to examine the trophic role of T. borellianus, in the floodplain of the Paraná River, and its relationships with the freshwater littoral community. The trophic spectrum of this species was characterized for both sexes and individuals of different sizes (adults and juveniles, throughout daily and seasonal cycles. Samples were collected from the aquatic vegetation of three shallow lakes. The diet composition and the feeding activity of T. borellianus were evaluated through the examination of the stomach contents and their degree of emptiness. This crab species consumed several plant and animal items, including amoebas, rotifers, oligochaetes, copepods, cladocerans, and insect larvae. Moreover, this species consumes filamentous and unicellular algae, diatoms, fungi, and macrophytic remains. The predatory habits varied with the season and time of day, and variations in the feeding activity of the juveniles and adults were detected and documented. The diversity of food items eaten by this crab suggests that its trophic role in the community as an omnivore and opportunistic predator provides a connection among several trophic levels from both aquatic and terrestrial communities.

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)

Northerners versus southerners: Italian anthropology and psychology faced with the "southern question".

Science.gov (United States)

Cimino, Guido; Foschi, Renato

2014-11-01

Following the Unification of Italy (1861), when confronted with the underdevelopment problems of the south that had given rise to the so-called "southern question," some Italian anthropologists and psychologists began to study the populations of the south from the psycho-anthropological point of view. These scientists, at times subject to preconceived ideas toward the southerners, conveyed observations and descriptions of the southern character traits that, in general, were considered different, in a negative sense, with respect to those of the northern peoples. To explain such diversity in the "psychological" characteristics between the north and south of the country (presumed cause also of the south's backwardness), various hypotheses were advanced related to the kind of heredity theory adopted, which could be of, more or less, an "innatist" or "transformist" or "environmentalist" kind. The distinction proposed in this article between at least 2 different "hereditarian" theories formulated by the Italian scientists, and the confrontation of these theories with the hypotheses expressed by the "southernist" sociologists, contrary to the idea of "racial varieties" present in the Italian population, allows one to understand in what way and in what sense, at the threshold of the 20th century, there arose the ideology of "Nordicism" and the roots of racism were planted.

The presence of species of Pseudochironomus Malloch 1915 (Diptera: Chironomidae) in watercourses of Chaco Serrano Ecoregion (Argentina, South America).

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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.

Extreme rainfall, vulnerability and risk: a continental-scale assessment for South America

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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.

Extreme rainfall, vulnerability and risk: a continental-scale assessment for South America.

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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.

South Africa : tous les projets | Page 7 | CRDI - Centre de ...

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

Sujet: Science and Technology, MEDICAL RESEARCH, HUMAN GENETICS, GENETIC ENGINEERING, BIOTECHNOLOGY. Région: Brazil, South America, China, Far East Asia, India, South Africa, North of Sahara, South of Sahara, North and Central America, Central Asia, South Asia, Canada. Programme: Économies en ...

Analysis and evaluation of WRF microphysical schemes for deep moist convection over south-eastern South America (SESA) using microwave satellite observations and radiative transfer simulations

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Sol Galligani, Victoria; Wang, Die; Alvarez Imaz, Milagros; Salio, Paola; Prigent, Catherine

2017-10-01

In the present study, three meteorological events of extreme deep moist convection, characteristic of south-eastern South America, are considered to conduct a systematic evaluation of the microphysical parameterizations available in the Weather Research and Forecasting (WRF) model by undertaking a direct comparison between satellite-based simulated and observed microwave radiances. A research radiative transfer model, the Atmospheric Radiative Transfer Simulator (ARTS), is coupled with the WRF model under three different microphysical parameterizations (WSM6, WDM6 and Thompson schemes). Microwave radiometry has shown a promising ability in the characterization of frozen hydrometeors. At high microwave frequencies, however, frozen hydrometeors significantly scatter radiation, and the relationship between radiation and hydrometeor populations becomes very complex. The main difficulty in microwave remote sensing of frozen hydrometeor characterization is correctly characterizing this scattering signal due to the complex and variable nature of the size, composition and shape of frozen hydrometeors. The present study further aims at improving the understanding of frozen hydrometeor optical properties characteristic of deep moist convection events in south-eastern South America. In the present study, bulk optical properties are computed by integrating the single-scattering properties of the Liu(2008) discrete dipole approximation (DDA) single-scattering database across the particle size distributions parameterized by the different WRF schemes in a consistent manner, introducing the equal mass approach. The equal mass approach consists of describing the optical properties of the WRF snow and graupel hydrometeors with the optical properties of habits in the DDA database whose dimensions might be different (Dmax') but whose mass is conserved. The performance of the radiative transfer simulations is evaluated by comparing the simulations with the available coincident

Cystic echinococcosis in South America: systematic review of species and genotypes of Echinococcus granulosus sensu lato in humans and natural domestic hosts.

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Cucher, Marcela Alejandra; Macchiaroli, Natalia; Baldi, Germán; Camicia, Federico; Prada, Laura; Maldonado, Lucas; Avila, Héctor Gabriel; Fox, Adolfo; Gutiérrez, Ariana; Negro, Perla; López, Raúl; Jensen, Oscar; Rosenzvit, Mara; Kamenetzky, Laura

2016-02-01

To systematically review publications on Echinococcus granulosus sensu lato species/genotypes reported in domestic intermediate and definitive hosts in South America and in human cases worldwide, taking into account those articles where DNA sequencing was performed; and to analyse the density of each type of livestock that can act as intermediate host, and features of medical importance such as cyst organ location. Literature search in numerous databases. We included only articles where samples were genotyped by sequencing since to date it is the most accurate method to unambiguously identify all E. granulosus s. l. genotypes. Also, we report new E. granulosus s. l. samples from Argentina and Uruguay analysed by sequencing of cox1 gene. In South America, five countries have cystic echinococcosis cases for which sequencing data are available: Argentina, Brazil, Chile, Peru and Uruguay, adding up 1534 cases. E. granulosus s. s. (G1) accounts for most of the global burden of human and livestock cases. Also, E. canadensis (G6) plays a significant role in human cystic echinococcosis. Likewise, worldwide analysis of human cases showed that 72.9% are caused by E. granulosus s. s. (G1) and 12.2% and 9.6% by E. canadensis G6 and G7, respectively. E. granulosus s. s. (G1) accounts for most of the global burden followed by E. canadensis (G6 and G7) in South America and worldwide. This information should be taken into account to suit local cystic echinococcosis control and prevention programmes according to each molecular epidemiological situation. © 2015 John Wiley & Sons Ltd.

Evidence for a possible modern and mid-Holocene solar influence on climate from Lake Titicaca, South America

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Theissen, K. M.; Dunbar, R. B.

2005-12-01

In tropical regions, there are few paleoclimate archives with the necessary resolution to investigate climate variability at interannual-to-decadal timescales prior to the onset of the instrumental record. Interannual variability associated with the El Niño Southern Oscillation (ENSO) is well documented in the instrumental record and the importance of the precessional forcing of millennial variability has been established in studies of tropical paleoclimate records. In contrast, decade-to-century variability is still poorly understood. Here, we examine interannual to decadal variability in the northern Altiplano of South America using digital image analysis of a floating interval of varved sediments of middle Holocene age (~6160-6310 yr BP) from Lake Titicaca. Multi-taper method (MTM) and wavelet frequency-domain analyses were performed on a time series generated from a gray-scaled digital image of the mm-thick laminations. Our results indicate significant power at a decadal periodicity (10-12 years) associated with the Schwabe cycle of solar activity. Frequency-domain analysis also indicates power at 2-2.5 year periodicities associated with ENSO. Similarly, spectral analysis of a 75 year instrumental record of Titicaca lake level shows significant power at both solar and ENSO periodicities. Although both of the examined records are short, our results imply that during both the mid-Holocene and modern times, solar and ENSO variability may have contributed to high frequency climate fluctuations over the northern Altiplano. We suspect that solar influence on large-scale atmospheric circulation features may account for the decadal variability in the mid-Holocene and present-day water balance of the Altiplano.

Variability and population genetic structure in Achyrocline flaccida (Weinm. DC., a species with high value in folk medicine in South America.

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Juliana da Rosa

Full Text Available Better knowledge of medicinal plant species and their conservation is an urgent need worldwide. Decision making for conservation strategies can be based on the knowledge of the variability and population genetic structure of the species and on the events that may influence these genetic parameters. Achyrocline flaccida (Weinm. DC. is a native plant from the grassy fields of South America with high value in folk medicine. In spite of its importance, no genetic and conservation studies are available for the species. In this work, microsatellite and ISSR (inter-simple sequence repeat markers were used to estimate the genetic variability and structure of seven populations of A. flaccida from southern Brazil. The microsatellite markers were inefficient in A. flaccida owing to a high number of null alleles. After the evaluation of 42 ISSR primers on one population, 10 were selected for further analysis of seven A. flaccida populations. The results of ISSR showed that the high number of exclusive absence of loci might contribute to the inter-population differentiation. Genetic variability of the species was high (Nei's diversity of 0.23 and Shannon diversity of 0.37. AMOVA indicated higher genetic variability within (64.7% than among (33.96% populations, and the variability was unevenly distributed (FST 0.33. Gene flow among populations ranged from 1.68 to 5.2 migrants per generation, with an average of 1.39. The results of PCoA and Bayesian analyses corroborated and indicated that the populations are structured. The observed genetic variability and population structure of A. flaccida are discussed in the context of the vegetation formation history in southern Brazil, as well as the possible anthropogenic effects. Additionally, we discuss the implications of the results in the conservation of the species.

First web-based database on total phenolics and oxygen radical absorbance capacity (ORAC) of fruits produced and consumed within the south Andes region of South America.

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Speisky, Hernan; López-Alarcón, Camilo; Gómez, Maritza; Fuentes, Jocelyn; Sandoval-Acuña, Cristian

2012-09-12

This paper reports the first database on antioxidants contained in fruits produced and consumed within the south Andes region of South America. The database ( www.portalantioxidantes.com ) contains over 500 total phenolics (TP) and ORAC values for more than 120 species/varieties of fruits. All analyses were conducted by a single ISO/IEC 17025-certified laboratory. The characterization comprised native berries such as maqui ( Aristotelia chilensis ), murtilla ( Ugni molinae ), and calafate ( Barberis microphylla ), which largely outscored all other studied fruits. Major differences in TP and ORAC were observed as a function of the fruit variety in berries, avocado, cherries, and apples. In fruits such as pears, apples, apricots, and peaches, a significant part of the TP and ORAC was accounted for by the antioxidants present in the peel. These data should be useful to estimate the fruit-based intake of TP and, through the ORAC data, their antioxidant-related contribution to the diet of south Andes populations.

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

Region: Mexico, North and Central America, South America. Program: Maternal and Child Health. Total Funding: CA$ 391,650.00. Understanding Southern Influence in Cyberspace Security and Governance: Toward a Global Network of Southern-based Cyber Scholars. Project. The securitization of cyberspace - that is, ...

Assessing and mapping drought hazard in Africa and South-Central America with a Meteorological Drought Severity Index

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Carrao, Hugo; Barbosa, Paulo; Vogt, Jürgen

2015-04-01

the intra-annual variability of precipitation in estimating the severity of events that can impact on seasonal activities. The MDSI is standardized in space and time, and considers the relative monthly precipitation deficits and the seasonal influence of precipitation regimes in the meteorological drought severity computation. In this study, the calculation of the MDSI is performed with monthly precipitation totals from the Full Data Reanalysis Monthly Product Version 6.0 of the Global Precipitation Climatology Centre (GPCC). This dataset provides a global analysis at 0.5 dd latitude/longitude grid spacing of monthly precipitation over land from operational in situ rain gauges collected between January 1901 and December 2010. Using the MDSI, we estimated the severity of drought events that occurred in the past 100 years in Africa and South-Central America, and produced drought hazard maps based on the probability of exceedance the median historical severity. Overall, results indicate that drought hazard is high for semiarid areas, such as Northeastern and Southern South America, as well as Eastern and Southwestern Africa. Since available water resources in semiarid areas are already insufficient to permanently meet the demands of human activities, the outcomes highlight the aggravated risk for food security and confirm the need for the implementation of disaster mitigation measures in those regions.

Treasures of the Southern Sky

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Gendler, Robert; Malin, David

2011-01-01

In these pages, the reader can follow the engaging saga of astronomical exploration in the southern hemisphere, in a modern merger of aesthetics, science, and a story of human endeavor. This book is truly a celebration of southern skies.  Jerry Bonnell, Editor - Astronomy Picture of the Day The southern sky became accessible to scientific scrutiny only a few centuries ago, after the first European explorers ventured south of the equator. Modern observing and imaging techniques have since revealed what seems like a new Universe, previously hidden below the horizon, a fresh astronomical bounty of beauty and knowledge uniquely different from the northern sky. The authors have crafted a book that brings this hidden Universe to all, regardless of location or latitude. Treasures of the Southern Sky celebrates the remarkable beauty and richness of the southern sky in words and with world-class imagery. In part, a photographic anthology of deep sky wonders south of the celestial equator, this book also celebrates th...

Hans Kelsen – The Reception of “Pure Theory” in South America, Particularly in Brazil

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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.

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

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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.

Improving precipitation simulation from updated surface characteristics in South America

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