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Sample records for casamayoran south american

  1. South American oil

    SciTech Connect

    Not Available

    1992-06-01

    GAO reviewed the petroleum industries of the following eight South American Countries that produce petroleum but are not major exporters: Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, and Trinidad and Tobago. This report discusses the amount of crude oil the United States imports from the eight countries, expected crude oil production for these countries through the year 2010, and investment reforms that these countries have recently made in their petroleum industries. In general, although the United States imports some oil from these countries, as a group, the eight countries are currently net oil importers because combined domestic oil consumption exceeds oil production. Furthermore, the net oil imports are expected to continue to increase through the year 2010, making it unlikely that the United States will obtain increased oil shipments from these countries.

  2. South American legal perspective on professional nursing.

    PubMed

    Campos, Fagner Alfredo Ardisson Cirino; Nekrassovski, Oleg

    This study involved a literature review aimed at describing the professional duties, stipulated in federal legislation, of nursing professionals in South America. According to the federal legislation that regulates the professional nursing practice, nurses are supposed to apply their skills and knowledge in an autonomous and secure way. Since it is through this legislation that professional competence of nurses is determined, the laws of each South American nation were consulted, to see how professional nursing functions differ according to each. In general, according to the South American federal nursing legislations, professional nursing practice must be grounded in quality patient care and good nursing administration. PMID:24260995

  3. Review of South American mines

    SciTech Connect

    Not Available

    1984-07-01

    A general overview is presented of the mining activity and plans for South America. The countries which are presented are Columbia, Argentina, Brazil, Venezuela, Chile, Peru, and Bolivia. The products of the mines include coal, bauxite, gold, iron, uranium, copper and numerous other minor materials. A discussion of current production, support and processing facilities, and mining strategies is also given.

  4. The Hungarian-Americans of South Bend.

    ERIC Educational Resources Information Center

    Scherer, Darlene; Rasmussen, Karen, Ed.

    Developed as part of an ethnic heritage studies program, this historical narrative of Hungarian Americans in South Bend, Indiana, is intended to increase cultural awareness and appreciation. The document is divided into three sections. Section I offers a brief history of Hungary and describes the background of the three emigrant groups; lower…

  5. More on South American geophysics

    NASA Astrophysics Data System (ADS)

    Lomnitz, Cinna

    As an addendum to J. Urrutia Fucugauchi's (Eos, 63, June 8, 1982, p. 529) excellent analysis of why things go wrong in Latin American geophysics, I submit that funds in whatever form are not the only answer. In Mexico over the past decade there has been a reasonable availability of funds, yet no dramatic increase in the quality or quantity of geophysical research was detected. Graduate scholarships have even gone begging for applicants in the earth sciences!Leadership is the big problem. National plans and forecasts for science and technology continue to ignore this central fact. They want to generate hundreds, nay thousands, of middle-level scientists while providing no incentive for excellence. As others have found out long before us, this approach is doomed from the start.

  6. Quebrada jaguay: early south american maritime adaptations

    PubMed

    Sandweiss; McInnis; Burger; Cano; Ojeda; Paredes; Sandweiss; Glascock

    1998-09-18

    Excavations at Quebrada Jaguay 280 (QJ-280) (16 degrees30'S) in south coastal Peru demonstrated that Paleoindian-age people of the Terminal Pleistocene (about 11,100 to 10,000 carbon-14 years before the present or about 13,000 to 11,000 calibrated years before the present) in South America relied on marine resources while resident on the coast, which extends the South American record of maritime exploitation by a millennium. This site supports recent evidence that Paleoindian-age people had diverse subsistence systems. The presence of obsidian at QJ-280 shows that the inhabitants had contact with the adjacent Andean highlands during the Terminal Pleistocene. PMID:9743490

  7. New native South American Y chromosome lineages.

    PubMed

    Jota, Marilza S; Lacerda, Daniela R; Sandoval, José R; Vieira, Pedro Paulo R; Ohasi, Dominique; Santos-Júnior, José E; Acosta, Oscar; Cuellar, Cinthia; Revollo, Susana; Paz-Y-Miño, Cesar; Fujita, Ricardo; Vallejo, Gustavo A; Schurr, Theodore G; Tarazona-Santos, Eduardo M; Pena, Sergio Dj; Ayub, Qasim; Tyler-Smith, Chris; Santos, Fabrício R

    2016-07-01

    Many single-nucleotide polymorphisms (SNPs) in the non-recombining region of the human Y chromosome have been described in the last decade. High-coverage sequencing has helped to characterize new SNPs, which has in turn increased the level of detail in paternal phylogenies. However, these paternal lineages still provide insufficient information on population history and demography, especially for Native Americans. The present study aimed to identify informative paternal sublineages derived from the main founder lineage of the Americas-haplogroup Q-L54-in a sample of 1841 native South Americans. For this purpose, we used a Y-chromosomal genotyping multiplex platform and conventional genotyping methods to validate 34 new SNPs that were identified in the present study by sequencing, together with many Y-SNPs previously described in the literature. We updated the haplogroup Q phylogeny and identified two new Q-M3 and three new Q-L54*(xM3) sublineages defined by five informative SNPs, designated SA04, SA05, SA02, SA03 and SA29. Within the Q-M3, sublineage Q-SA04 was mostly found in individuals from ethnic groups belonging to the Tukanoan linguistic family in the northwest Amazon, whereas sublineage Q-SA05 was found in Peruvian and Bolivian Amazon ethnic groups. Within Q-L54*, the derived sublineages Q-SA03 and Q-SA02 were exclusively found among Coyaima individuals (Cariban linguistic family) from Colombia, while Q-SA29 was found only in Maxacali individuals (Jean linguistic family) from southeast Brazil. Furthermore, we validated the usefulness of several published SNPs among indigenous South Americans. This new Y chromosome haplogroup Q phylogeny offers an informative paternal genealogy to investigate the pre-Columbian history of South America.Journal of Human Genetics advance online publication, 31 March 2016; doi:10.1038/jhg.2016.26. PMID:27030145

  8. Ocean drilling bordering the South American continent

    SciTech Connect

    Rabinowitz, P.D.; Francis, T.J.G.; Baldauf, J.G.; Allan, J.F. )

    1993-02-01

    The Ocean Drilling Program (ODP) has completed three expeditions bordering South America and is in the planning stages of a further expedition. The first cruise, Leg 110, drilled at six sites on a transect across the structural boundary between the overthrusting Barbados Ridge Complex and Atlantic abyssal plain (Caribbean/Atlantic Plate Boundary) in order to investigate structural, hydrological, and diagenetic effects of the transition from undeformed deep sea sediments to stratally disrupted melange on land. The second cruise, Leg 112, drilled ten sites to investigate the geological and paleoceanographic history of the area between the Peru Trench (which marks the suture between the Nazca and South American Plates) and the Peruvian coast. A third cruise, Leg 1 41, drilled the Chile Triple Junction, which represents the only presently active ridge-crest subduction and the physical properties and geochemistry of gas hydrates in oceanic sediments. A fourth cruise off South America is presently in the planning stage by the international science community. This proposed paleoceanographic transect is on the Ceara Rise off northern Brazil and has a proposed objective, amongst others, of studying the history of deep water flow of the Atlantic during the Cenozoic with an emphasis on the relationships between deep water circulation chemistry and the Earth's climate. This paper focuses on the significant scientific results of the above cruises and discusses future plans off South America.

  9. 19. Historic American Buildings Survey Stanley Schwartz, Photographer 1971 SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Historic American Buildings Survey Stanley Schwartz, Photographer 1971 SOUTH WALL OF WAITING ROOM, DOCTOR'S OFFICE - Governor John Hubbard House, 52 Winthrop Street, Hallowell, Kennebec County, ME

  10. Historic American Buildings Survey Marc Blair Photographer, summer 1966 SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Historic American Buildings Survey Marc Blair Photographer, summer 1966 SOUTH ELEVATION from SOUTHWEST - Grace Protestant Episcopal Church, 1041 Wisconsin Avenue Northwest, Washington, District of Columbia, DC

  11. Cultural and Rhetorical Adaptations for South American Audiences.

    ERIC Educational Resources Information Center

    Thatcher, Barry L.

    1999-01-01

    Explores intercultural communication in one multinational organization in Quito, Ecuador where United States and South American personnel developed documentation and instructional texts. Finds that communication of South Americans was usually oral, contextual, concrete, personal, and narrative; and that of U.S. personnel was written, acontextual,…

  12. Two new species of South American Glaresidae (Coleoptera: Scarabaeoidea).

    PubMed

    Paulsen, M J

    2016-01-01

    Two new species of South American Glaresidae (Coleoptera: Scarabaeoidea) are described: Glaresis smithi Paulsen, new species from Argentina, and Glaresis mondacai Paulsen, new species from Chile and Peru. The species are compared to their closest congener, Glaresis fritzi Martínez et al., and a key is provided for the known South American species of the genus Glaresis Erichson. PMID:27615864

  13. Oral manifestations of paracoccidioidomycosis (South American blastomycosis).

    PubMed

    de Almeida, O P; Jorge, J; Scully, C; Bozzo, L

    1991-10-01

    Paracoccidioidomycosis (South American blastomycosis) is an uncommon, progressive systemic mycosis, potentially fatal if untreated. It is virtually restricted to persons spending time in Latin America. Reports of oral lesions are extremely rare in the English-language literature. Three adults with oral lesions as the first sign of paracoccidioidomycosis are described; this appears to be the largest series in the dental literature. The oral lesions had a characteristic appearance with a granular purpuric surface. The upper gingiva was a typical site, but lesions were also seen in the palate, tongue, and buccal mucosa. Two of the patients proved to have detectable pulmonary involvement. Long-term systemic ketoconazole therapy produced resolution of oral lesions in all cases. PMID:1923441

  14. Interannual variability of South American monsoon circulation

    NASA Astrophysics Data System (ADS)

    Alonso Gan, Manoel; Rafaele Araújo Lima, Jeane

    2016-04-01

    The South America Monsoon System (SAMS) is responsible for influencing the atmospheric circulation and precipitation over most of tropical South America (SA) during the summer season. Studies for aiming to understand the temporal variability of this system have great value to the scientific community, because the processes that control the monsoon climate are not totally clear. Thus, the main objective of this research is to investigate the possible large-scale climatic factors and the remote interaction mechanisms, which may be associated with summer season interannual variability focusing on identifying the main differences between dry and wet extremes rainy season in the South-eastern Amazon Basin (SAB), Central-West (WC) and Southeast (SE) of Brazil, which are areas influenced by the summer monsoon regime. For such analyzes, Pearson correlations, quantile method and composite analysis were used during the period from 1979 to 2014. The correlation between precipitation anomaly in SAB and the sea surface temperature anomaly (SSTA) and wind at 850hPa and 300hPa indicate El Niño-Southern Oscillation (ENSO) influence. Precipitation anomalies in WC did not show significant correlation with SSTA. However, a pattern similar to ENSO Modoki type was observed in the composite analysis. At 850 hPa, the presence of an anomalous cyclonic (anticyclonic) circulation was observed over the central region of SA during wet (dry) summers seasons. Over SE region of Brazil, a dipole SSTA pattern over the South Atlantic was identified, as well the presence of anomalous circulations with an equivalent barotropic structure over these SSTA areas. This pattern is more evident in case of dry summer on the SE. At 300 hPa, the wave train between 30°S-60°S was observed presenting a feature curvature from 120°W reaching SA, similar to the Pacific-South American pattern (PSA). Analysis of the summer interannual variability indicated the manifestation of wet summers more frequently than dry

  15. Detection of different South American hantaviruses.

    PubMed

    Guterres, Alexandro; de Oliveira, Renata Carvalho; Fernandes, Jorlan; Schrago, Carlos Guerra; de Lemos, Elba Regina Sampaio

    2015-12-01

    Hantaviruses are the etiologic agents of Hemorrhagic Fever with Renal Syndrome (HFRS) in Old World, and Hantavirus Pulmonary Syndrome (HPS)/Hantavirus Cardiopulmonary Syndrome (HCPS), in the New World. Serological methods are the most common approach used for laboratory diagnosis of HCPS, however theses methods do not allow the characterization of viral genotypes. The polymerase chain reaction (PCR) has been extensively used for diagnosis of viral infections, including those caused by hantaviruses, enabling detection of few target sequence copies in the sample. However, most studies proposed methods of PCR with species-specific primers. This study developed a simple and reliable diagnostic system by RT-PCR for different hantavirus detection. Using new primers set, we evaluated human and rodent hantavirus positive samples of various regions from Brazil. Besides, we performed computational analyzes to evaluate the detection of other South American hantaviruses. The diagnostic system by PCR proved to be a sensible and simple assay, allowing amplification of Juquitiba virus, Araraquara virus, Laguna Negra virus, Rio Mamore virus and Jabora virus, beyond of the possibility of the detecting Andes, Anajatuba, Bermejo, Choclo, Cano Delgadito, Lechiguanas, Maciel, Oran, Pergamino and Rio Mearim viruses. The primers sets designed in this study can detect hantaviruses from almost all known genetics lineages in Brazil and from others South America countries and also increases the possibility to detect new hantaviruses. These primers could easily be used both in diagnosis of suspected hantavirus infections in humans and also in studies with animals reservoirs. PMID:26220480

  16. Investigating Mechanisms of South American Flat Subduction

    NASA Astrophysics Data System (ADS)

    Hu, J.; Hermosillo, A.; Liu, L.

    2014-12-01

    Flat-slab subduction is a pronounced tectonic phenomenon occurring at 10% of the convergence plate boundaries today. Causes of flat-slab formation remain debated, where proposed mechanisms include subduction of buoyancy anomalies such as oceanic plateaus and aseismic ridges, dynamic suction from thickened overriding plate, and enhanced subduction speed and reduced seafloor ages. South America represents an ideal place to test these hypotheses, with ongoing flat subduction as well as possible flat-slab scenarios during the geological past. Here, we use geodynamic models with plate kinematics and seafloor ages as boundary conditions to reproduce the history of South American subduction since the Late Cretaceous, during which we attempt to investigate the dynamic causes and impacts of flat subduction. The modeling results will be compared to present-day upper mantle slab geometry through slab 1.0 [Hayes et al, 2012] and lower mantle structures in several tomography models including GyPSuM [Simmons et al, 2010] and S20RTS [Ritsema et al. 1999].

  17. Diagnosis of the South American Monsoon Variability

    NASA Astrophysics Data System (ADS)

    Alonso Gan, Manoel; Aragão Ferreira, Solange

    2014-05-01

    In order to understand the space-time evolution of the dominant modes that constitute the South American Monsoon System (SAMS), cyclostationary EOF analysis was applied in the region between 20°N-60°S and 0°-90°E and for 29 summers (from 1978/79 to 2007/08) to the Xie-Arkin pentad precipitation data and other synoptic variables during the life cycle of the SAMS (September to March). This analysis shows detailed features of the first three dominant modes. The first mode of precipitation represents the seasonal cycle, the second mode explains the cold phase of El Niño-South Oscillation (ENSO) (La Niña) signal, and the third mode describes the transition phase of ENSO between La Niña and El Niño and possible interaction of the Madden Julian Oscillation (MJO). All three modes together explain about 26% of the total variance of the pentad precipitation data. The most pronounced feature of the seasonal cycle is strongly associated with the positive anomalies of surface temperature during the rainy season onset that develop over the tropical region of the continent. Associated with these temperature anomalies changes in the sea level pressure (SLP) field are observed. During the end of the dry season, the surface temperature over the SAMS core increases and consequently SLP decreases. This initiates an cyclonic circulation over central region of South America (SA), known as Chaco low. The increased upward motion induced by the surface warming together with the anomalous cyclonic circulation results in the increased of low-level moisture transport from Amazon region toward central region of SA by the low-level northwesterly flow. This situation increases the amount of precipitation in SAMS core and starts the rainy season in this region. During the termination stage, these conditions over SA are reversed. The ENSO mode reveals that the following factors affect the evolution of the SAMS system in La Niña years. (1) Negative 1000-hPa temperature anomalies over the

  18. 1. Historic American Buildings Survey, August, 1971 SOUTH (FRONT) ELEVATIONS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, August, 1971 SOUTH (FRONT) ELEVATIONS AT LOVE AND BILGER TIN SHOP (LEFT) AND SACHS BROTHERS STORE (RIGHT). - Love & Bilger Tin Shop, 150 West California Street, Jacksonville, Jackson County, OR

  19. 37. Historic American Buildings Survey L. C. Durette, Photographer SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    37. Historic American Buildings Survey L. C. Durette, Photographer SOUTH WEST ROOM 2nd. FLOOR CHIMNEY GIRT HAS BEEN CUT BACK TO MAKE LATER PLASTER WALL FLUSH - Doe Garrison, Lamprey River & Great Bay, Newmarket, Rockingham County, NH

  20. 28. Historic American Buildings Survey L. C. Durette, Photographer SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. Historic American Buildings Survey L. C. Durette, Photographer SOUTH WINDOW OF EAST ROOM (See Description) First Floor, SPLIT BOARDS USED FOR LATHS ARE OLD OUTSIDE FINISH USED OVER. - Doe Garrison, Lamprey River & Great Bay, Newmarket, Rockingham County, NH

  1. A Comparison Between Mexican-American and South American Students: A Cross-Cultural Study.

    ERIC Educational Resources Information Center

    Escotet, Miguel A.

    Addressing problem areas Mexican American students identify as important and differences between South American and Mexican American student problems, this research was guided by earlier work on cross-cultural methods and student problems. The study involved 1,189 high school and university students from Chile, Columbia, Ecuador, Venezuela,…

  2. Teaching Experiences of African American Educators in the Rural South

    ERIC Educational Resources Information Center

    Polidore, Ellene; Edmonson, Stacey L.; Slate, John R.

    2010-01-01

    A scarcity of research exists regarding the voices of African American teachers who taught in the rural South. In this study, we report the life experiences, perceptions, thoughts, and feelings of three female African American educators as they pertain to their experiences teaching before, during, and after desegregation. Three female African…

  3. Early Miocene origin and cryptic diversification of South American salamanders

    PubMed Central

    2013-01-01

    Background The currently recognized species richness of South American salamanders is surprisingly low compared to North and Central America. In part, this low richness may be due to the salamanders being a recent arrival to South America. Additionally, the number of South American salamander species may be underestimated because of cryptic diversity. The aims of our present study were to infer evolutionary relationships, lineage diversity, and timing of divergence of the South American Bolitoglossa using mitochondrial and nuclear sequence data from specimens primarily from localities in the Andes and upper Amazon Basin. We also estimated time of colonization of South America to test whether it is consistent with arrival via the Panamanian Isthmus, or land bridge connection, at its traditionally assumed age of 3 million years. Results Divergence time estimates suggest that Bolitoglossa arrived in South America from Central America by at least the Early Miocene, ca. 23.6 MYA (95% HPD 15.9-30.3 MYA), and subsequently diversified. South American salamanders of the genus Bolitoglossa show strong phylogeographic structure at fine geographic scales and deep divergences at the mitochondrial gene cytochrome b (Cytb) and high diversity at the nuclear recombination activating gene-1 (Rag1). Species often contain multiple genetically divergent lineages that are occasionally geographically overlapping. Single specimens from two southeastern localities in Ecuador are sister to the equatoriana-peruviana clade and genetically distinct from all other species investigated to date. Another single exemplar from the Andes of northwestern Ecuador is highly divergent from all other specimens and is sister to all newly studied samples. Nevertheless, all sampled species of South American Bolitoglossa are members of a single clade that is one of several constituting the subgenus Eladinea, one of seven subgenera in this large genus. Conclusions The ancestors of South American salamanders

  4. Mexican-Americans of South Texas.

    ERIC Educational Resources Information Center

    Madsen, William

    The Hogg Foundation for Mental Health sponsored and financed the Hidalgo Project on Differential Culture Change and Mental Health during the 4-year period from 1957 to 1961; this document is an abbreviated report of that study of Mexican-American culture in Hidalgo County, Texas. Acculturation levels of various classes of the Mexican-American…

  5. Tenancy and African American Marriage in the Postbellum South.

    PubMed

    Bloome, Deirdre; Muller, Christopher

    2015-10-01

    The pervasiveness of tenancy in the postbellum South had countervailing effects on marriage between African Americans. Tenancy placed severe constraints on African American women's ability to find independent agricultural work. Freedwomen confronted not only planters' reluctance to contract directly with women but also whites' refusal to sell land to African Americans. Marriage consequently became one of African American women's few viable routes into the agricultural labor market. We find that the more counties relied on tenant farming, the more common was marriage among their youngest and oldest African American residents. However, many freedwomen resented their subordinate status within tenant marriages. Thus, we find that tenancy contributed to union dissolution as well as union formation among freedpeople. Microdata tracing individuals' marital transitions are consistent with these county-level results. PMID:26223562

  6. 8. Historic American Buildings Survey April 1949 FRONT (SOUTH) ELEVATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Historic American Buildings Survey April 1949 FRONT (SOUTH) ELEVATION - Southeast Area Survey, 600-602 & 1100 G Street (House), 1002,1006 Eye Street (House), 808-810,812-814, & 1016 K Street (House), 817-819 L Street (House), Washington, District of Columbia, DC

  7. 7. Historic American Buildings Survey April 1959 FRONT (SOUTH) ELEVATION. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. Historic American Buildings Survey April 1959 FRONT (SOUTH) ELEVATION. 812 (LEFT) 814 (RIGHT) - Southeast Area Survey, 600-602 & 1100 G Street (House), 1002,1006 Eye Street (House), 808-810,812-814, & 1016 K Street (House), 817-819 L Street (House), Washington, District of Columbia, DC

  8. 11. Historic American Buildings Survey Photocopy PRINCIPAL FLOOR PLAN, SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Historic American Buildings Survey Photocopy PRINCIPAL FLOOR PLAN, SOUTH SIDE ELEVATION ARCHITECT'S ORIGINAL PLAN Restricted: Not to be reproduced without written permission from Beinecke Rare Books Library, Yale University, New Haven, Connecticut - John Pitkin Norton House, 52 Hillhouse Avenue, New Haven, New Haven County, CT

  9. 1. Historic American Buildings Survey EAST AND SOUTH ELEVATIONS BEFORE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey EAST AND SOUTH ELEVATIONS BEFORE ADDITION OF PORCH, ALTERATION OF WINDOWS From the Collection of the Title Insurance Company, SanDiego, Negative FEP - 1323 - Temple Beth Israel, 1502 Second Avenue, San Diego, San Diego County, CA

  10. 1. Historic American Buildings Survey, August, 1971 STREETSCAPE SHOWING SOUTH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, August, 1971 STREETSCAPE SHOWING SOUTH (FRONT) ELEVATIONS OF LOVE AND BILGER TIN SHOP (FAR LEFT), SACHS BROTHERS STORE, NEUBER'S JEWELRY STORE, KAHLER'S DRUG STORE, BEEKMAN BANK, UNITED STATES HOTEL. - Neuber's Jewelry Store, 130 West California Street, Jacksonville, Jackson County, OR

  11. 1. Historic American Buildings Survey, August, 1971 SOUTH (FRONT) ELEVATIONS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, August, 1971 SOUTH (FRONT) ELEVATIONS OF CORNER OF UNITED STATES HOTEL (FAR LEFT), JUDGE AND NUNAN'S SADDLERY, P.J. RYAN'S FIRST BRICK STORE BUILDING (JACKSONVILLE INN). - P. J. Ryan's First Brick Store Building, 175 East California Street, Jacksonville, Jackson County, OR

  12. 1. Historic American Buildings Survey, August, 1979 SOUTH (FRONT) ELEVATIONS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Historic American Buildings Survey, August, 1979 SOUTH (FRONT) ELEVATIONS OF CORNER OF UNITED STATES HOTEL (FAR LEFT), JUDGE AND NUNAN'S SADDLERY, P.J. RYAN'S FIRST BRICK STORE BUILDING (JACKSONVILLE INN). - Judge & Nunan's Saddlery, 165 East California Street, Jacksonville, Jackson County, OR

  13. Can Indian Ocean SST anomalies influence South American rainfall?

    NASA Astrophysics Data System (ADS)

    Taschetto, Andréa S.; Ambrizzi, Tércio

    2012-04-01

    In this study we examine the impact of Indian Ocean sea surface temperature (SST) variability on South American circulation using observations and a suite of numerical experiments forced by a combination of Indian and Pacific SST anomalies. Previous studies have shown that the Indian Ocean Dipole (IOD) mode can affect climate over remote regions across the globe, including over South America. Here we show that such a link exists not only with the IOD, but also with the Indian Ocean basin-wide warming (IOBW). The IOBW, a response to El Niño events, tends to reinforce the South American anomalous circulation in March-to-May associated with the warm events in the Pacific. This leads to increased rainfall in the La Plata basin and decreased rainfall over the northern regions of the continent. In addition, the IOBW is suggested to be an important factor for modulating the persistence of dry conditions over northeastern South America during austral autumn. The link between the IOBW and South American climate occurs via alterations of the Walker circulation pattern and through a mid-latitude wave-train teleconnection.

  14. Early South Americans Cranial Morphological Variation and the Origin of American Biological Diversity

    PubMed Central

    Hubbe, Alex; Neves, Walter A.

    2015-01-01

    Recent South Americans have been described as presenting high regional cranial morphological diversity when compared to other regions of the world. This high diversity is in accordance with linguistic and some of the molecular data currently available for the continent, but the origin of this diversity has not been satisfactorily explained yet. Here we explore if this high morphological variation was already present among early groups in South America, in order to refine our knowledge about the timing and origins of the modern morphological diversity. Between-group (Fst estimates) and within-group variances (trace of within-group covariance matrix) of the only two early American population samples available to date (Lagoa Santa and Sabana de Bogotá) were estimated based on linear craniometric measurements and compared to modern human cranial series representing six regions of the world, including the Americas. The results show that early Americans present moderate within-group diversity, falling well within the range of modern human groups, despite representing almost three thousand years of human occupation. The between-group variance apportionment is very low between early Americans, but is high among recent South American groups, who show values similar to the ones observed on a global scale. Although limited to only two early South American series, these results suggest that the high morphological diversity of native South Americans was not present among the first human groups arriving in the continent and must have originated during the Middle Holocene, possibly due to the arrival of new morphological diversity coming from Asia during the Holocene. PMID:26465141

  15. Early South Americans Cranial Morphological Variation and the Origin of American Biological Diversity.

    PubMed

    Hubbe, Mark; Strauss, André; Hubbe, Alex; Neves, Walter A

    2015-01-01

    Recent South Americans have been described as presenting high regional cranial morphological diversity when compared to other regions of the world. This high diversity is in accordance with linguistic and some of the molecular data currently available for the continent, but the origin of this diversity has not been satisfactorily explained yet. Here we explore if this high morphological variation was already present among early groups in South America, in order to refine our knowledge about the timing and origins of the modern morphological diversity. Between-group (Fst estimates) and within-group variances (trace of within-group covariance matrix) of the only two early American population samples available to date (Lagoa Santa and Sabana de Bogotá) were estimated based on linear craniometric measurements and compared to modern human cranial series representing six regions of the world, including the Americas. The results show that early Americans present moderate within-group diversity, falling well within the range of modern human groups, despite representing almost three thousand years of human occupation. The between-group variance apportionment is very low between early Americans, but is high among recent South American groups, who show values similar to the ones observed on a global scale. Although limited to only two early South American series, these results suggest that the high morphological diversity of native South Americans was not present among the first human groups arriving in the continent and must have originated during the Middle Holocene, possibly due to the arrival of new morphological diversity coming from Asia during the Holocene. PMID:26465141

  16. Phylogenetic reconstruction of South American felids defined by protein electrophoresis.

    PubMed

    Slattery, J P; Johnson, W E; Goldman, D; O'Brien, S J

    1994-09-01

    Phylogenetic associations among six closely related South American felid species were defined by changes in protein-encoding gene loci. We analyzed proteins isolated from skin fibroblasts using two-dimensional electrophoresis and allozymes extracted from blood cells. Genotypes were determined for multiple individuals of ocelot, margay, tigrina, Geoffroy's cat, kodkod, and pampas cat at 548 loci resolved by two-dimensional electrophoresis and 44 allozyme loci. Phenograms were constructed using the methods of Fitch-Margoliash and neighbor-joining on a matrix of Nei's unbiased genetic distances for all pairs of species. Results of a relative-rate test indicate changes in two-dimensional electrophoresis data are constant among all South American felids with respect to a hyena outgroup. Allelic frequencies were transformed to discrete character states for maximum parsimony analysis. Phylogenetic reconstruction indicates a major split occurred approximately 5-6 million years ago, leading to three groups within the ocelot lineage. The earliest divergence led to Leopardus tigrina, followed by a split between an ancestor of an unresolved trichotomy of three species (Oncifelis guigna, O. geoffroyi, and Lynchailuris colocolo) and a recent common ancestor of Leopardus pardalis and L. wiedii. The results suggest that modern South American felids are monophyletic and evolved rapidly after the formation of the Panama land bridge between North and South America. PMID:7932791

  17. Increased arterial stiffness in South Dakota American Indian children.

    PubMed

    Litz, Andrew M; Van Guilder, Gary P

    2016-02-01

    Arterial stiffness has been observed in white American obese children, yet there are no data in American Indian youth, who are affected disproportionately by the cardiovascular consequences of childhood obesity and its accompanying risk factors. The purpose of this study was to determine the association of childhood overweight-obesity and cardiometabolic risk factors with arterial stiffness in South Dakota white American and American Indian children. Thirty-six (28 white American and 8 American Indian) children (age, 13 ± 1 years; grades 6-8) from a rural South Dakota elementary and middle school were studied: 18 had a healthy weight (body mass index (BMI), 19.5 ± 1.9 kg/m(2)) and 18 were overweight-obese (BMI, 26.8 ± 3.5 kg/m(2)). Arterial stiffness was assessed using applanation tonometry via pulse wave analysis to determine carotid-radial pulse wave velocity (crPWV) and aortic augmentation index (AIx). There were no differences (P = 0.94) in crPWV between healthy weight (7.1 ± 1.4 m/s) and overweight-obese (7.3 ± 1.0 m/s) children, even after controlling for risk factors. However, crPWV was markedly elevated (P = 0.002) in overweight-obese American Indian children (7.7 ± 1.1 m/s) compared with white American children (6.8 ± 0.5 m/s), and these differences remained after controlling for blood pressure and more severe obesity in the American Indians. An obesity-matched subgroup analysis indicated that crPWV (7.7 ± 1.1 vs 6.8 ± 0.4 m/s) remained significantly greater in the American Indians (P = 0.03). There were no between-group differences in aortic AIx. These findings indicate an adverse influence of American Indian ethnicity on arterial stiffening in children with elevated adiposity. Arterial stiffness in American Indian children may accelerate early adulthood vascular disease. PMID:26761621

  18. High-Throughput Sequencing of a South American Amerindian

    PubMed Central

    Almeida, Renan; Alencar, Dayse O.; Barbosa, Maria Silvanira; Gusmão, Leonor; Silva, Wilson A.; de Souza, Sandro J.; Silva, Artur; Ribeiro-dos-Santos, Ândrea; Darnet, Sylvain; Santos, Sidney

    2013-01-01

    The emergence of next-generation sequencing technologies allowed access to the vast amounts of information that are contained in the human genome. This information has contributed to the understanding of individual and population-based variability and improved the understanding of the evolutionary history of different human groups. However, the genome of a representative of the Amerindian populations had not been previously sequenced. Thus, the genome of an individual from a South American tribe was completely sequenced to further the understanding of the genetic variability of Amerindians. A total of 36.8 giga base pairs (Gbp) were sequenced and aligned with the human genome. These Gbp corresponded to 95.92% of the human genome with an estimated miscall rate of 0.0035 per sequenced bp. The data obtained from the alignment were used for SNP (single-nucleotide) and INDEL (insertion-deletion) calling, which resulted in the identification of 502,017 polymorphisms, of which 32,275 were potentially new high-confidence SNPs and 33,795 new INDELs, specific of South Native American populations. The authenticity of the sample as a member of the South Native American populations was confirmed through the analysis of the uniparental (maternal and paternal) lineages. The autosomal comparison distinguished the investigated sample from others continental populations and revealed a close relation to the Eastern Asian populations and Aboriginal Australian. Although, the findings did not discard the classical model of America settlement; it brought new insides to the understanding of the human population history. The present study indicates a remarkable genetic variability in human populations that must still be identified and contributes to the understanding of the genetic variability of South Native American populations and of the human populations history. PMID:24386182

  19. South American mega cities: Knowledge gaps and collaboration opportunities

    NASA Astrophysics Data System (ADS)

    Gallardo, L.

    2012-04-01

    Urbanization and population concentration are outstanding phenomena in South America. About 83% of the 530 million South Americans live already in large coastal or near coastal cities (> 750 k inhabitants), many of which are heavily polluted. Curbing measures have been implemented on a relatively fast pace taking advantage of lessons learned elsewhere. However, as environmental objectives become more ambitious, considering for instance chronic health effects, impacts on ecosystems and agriculture, addressing secondary particles and climatic impacts, the need for cost-effective measures requires of more reliable and locally representative data. Such data include: emission fluxes (both natural and anthropogenic) and emission scenarios; characterization of vertical mixing; speciation and distribution of pollutants and precursors. In this presentation, we review the current situation in terms of atmospheric modeling, emission modeling, measuring and observations in a number of South American cities. Also, we describe low-cost actions oriented towards improving our understanding of: 1) vertical mixing by means of a modeling inter comparison exercise using data already collected in Santiago de Chile; 2) aerosol composition and speciation of volatile organic compounds by means of a coordinated sampling of filters and canisters at various locations highlighting the diversity of our cities. These actions were collectively convened by ca. 50 leading scientists and local policy makers during an international symposium held in Santiago in January 2012 (http://ossaf.cmm.uchile.cl/). This activity marked the closure of a five year project sponsored by the Inter American Institute on Global Change Research that tackled South American Emissions Megacities and Climate (SAEMC, CRN 2017). It was also a regional activity promoted and sponsored by the international Commission on Atmospheric Chemistry and Global Pollution (iCACGP), and by the World

  20. An overview of the South American fossil squamates.

    PubMed

    Albino, Adriana María; Brizuela, Santiago

    2014-03-01

    The evolution of squamates in South America is the result of the complex geological and paleoclimatic history of this part of the world. The incomplete and episodic fossil record allows us to know only a small part of this evolution. Most Mesozoic squamate remains come from the Patagonian region, but remarkable specimens have also been recovered from Brazil. Both major squamate clades (Iguania and Scleroglossa) are present in the South American Mesozoic. Remains of Mesozoic snakes are common and diverse in Cretaceous deposits, including some of the most primitive terrestrial forms. Paleogene and Neogene squamate remains have been recognized from Argentina, Bolivia, Brazil, Colombia, Ecuador, Peru, and Venezuela. Paleogene lizard record appears to be scarce in comparison to that of the Mesozoic, whereas snakes show an important Paleogene diversity. At least two extant boid snakes appeared during this epoch (Boa and Corallus). The South American Miocene included some extant genera of Iguania, Teiidae, and Boidae but extinct genera were also present. "Colubrids" appeared at the early Miocene, whereas the first viperid is known from the late Miocene. Most of the Paleogene and early Neogene squamate families and genera have been recognized outside their current range of distribution following favorable climatic conditions for ectothermic vertebrates. During the latest Miocene and Pliocene few extant squamate taxa are found to occur outside their present distribution. The earliest amphisbaenian of South America is known from the Pliocene. Most Pleistocene and Holocene squamate remains are assigned to living genera, and some extant species were recognized. PMID:24482358

  1. South American palaeobotany and the origins of neotropical rainforests.

    PubMed

    Burnham, Robyn J; Johnson, Kirk R

    2004-10-29

    Extant neotropical rainforest biomes are characterized by a high diversity and abundance of angiosperm trees and vines, high proportions of entire-margined leaves, high proportions of large leaves (larger than 4500 mm2), high abundance of drip tips and a suite of characteristic dominant families: Sapotaceae, Lauraceae, Leguminosae (Fabaceae), Melastomataceae and Palmae (Arecaceae). Our aim is to define parameters of extant rainforests that will allow their recognition in the fossil record of South America and to evaluate all known South American plant fossil assemblages for first evidence and continued presence of those parameters. We ask when did these critical rainforest characters arise? When did vegetative parameters reach the level of abundance that we see in neotropical forests? Also, when do specific lineages become common in neotropical forests? Our review indicates that evidence of neotropical rainforest is exceedingly rare and equivocal before the Palaeocene. Even in the Palaeocene, the only evidence for tropical rainforest in South America is the appearance of moderately high pollen diversity. By contrast, North American sites provide evidence that rainforest leaf physiognomy was established early in the Palaeocene. By the Eocene in South America, several lines of evidence suggest that neotropical rainforests were diverse, physiognomically recognizable as rainforest and taxonomically allied to modern neotropical rainforests. A mismatch of evidence regarding the age of origin between sites of palaeobotanical high diversity and sites of predicted tropical climates should be reconciled with intensified collecting efforts in South America. We identify several lines of promising research that will help to coalesce previously disparate approaches to the origin, longevity and maintenance of high diversity floras of South America. PMID:15519975

  2. South American palaeobotany and the origins of neotropical rainforests.

    PubMed Central

    Burnham, Robyn J; Johnson, Kirk R

    2004-01-01

    Extant neotropical rainforest biomes are characterized by a high diversity and abundance of angiosperm trees and vines, high proportions of entire-margined leaves, high proportions of large leaves (larger than 4500 mm2), high abundance of drip tips and a suite of characteristic dominant families: Sapotaceae, Lauraceae, Leguminosae (Fabaceae), Melastomataceae and Palmae (Arecaceae). Our aim is to define parameters of extant rainforests that will allow their recognition in the fossil record of South America and to evaluate all known South American plant fossil assemblages for first evidence and continued presence of those parameters. We ask when did these critical rainforest characters arise? When did vegetative parameters reach the level of abundance that we see in neotropical forests? Also, when do specific lineages become common in neotropical forests? Our review indicates that evidence of neotropical rainforest is exceedingly rare and equivocal before the Palaeocene. Even in the Palaeocene, the only evidence for tropical rainforest in South America is the appearance of moderately high pollen diversity. By contrast, North American sites provide evidence that rainforest leaf physiognomy was established early in the Palaeocene. By the Eocene in South America, several lines of evidence suggest that neotropical rainforests were diverse, physiognomically recognizable as rainforest and taxonomically allied to modern neotropical rainforests. A mismatch of evidence regarding the age of origin between sites of palaeobotanical high diversity and sites of predicted tropical climates should be reconciled with intensified collecting efforts in South America. We identify several lines of promising research that will help to coalesce previously disparate approaches to the origin, longevity and maintenance of high diversity floras of South America. PMID:15519975

  3. Anomalies in the South American Monsoon Induced by Aerosols

    NASA Technical Reports Server (NTRS)

    Lau, K. M. William; Kyu-Mong, Kim

    2007-01-01

    We have investigated the direct effects of aerosols on the water cycle of the South American monsoon using the NASA finite-volume general circulation model (fvGCM). Global aerosol forcings are computed from radiative transfer functions derived from global distributions of five species of aerosols, i.e., dust, black carbon, organic carbon, sulphate and sea salt from the Goddard Chemistry Aerosol Radiation Transport (GOCART) model. Comparing fvGCM experiments without aerosol forcing, and with different combinations of aerosol forcing, we evaluate the impacts of aerosol direct heating on the onset, maintenance and evolution of the South American summer monsoon. We find that during the pre-monsoon season (September-October-November) Saharan dust contribute to heating of the atmosphere over the central and eastern equatorial Atlantic/Africa region through the elevated heat pump mechanism. The heating generates an anomalous Walker circulation with sinking motion, and low level northeasterlies over the Caribbean and northwestern South America. The low level flow is blocked by the Andes, and turn south and southeastward, increasing the low level jet (LLJ) along the eastern slope of the Andes. The increased LLJ transports more moisture from the Atlantic and the Amazon, enhancing the moisture convergence over subtropical land regions of South America. The moisture convergence was further accelerated by atmospheric heating by biomass burning over the Amazon. The net results of the dust and biomass heating are: a) an advance of the monsoon rainy season, b) an enhanced LLJ and c) a shifting the South America monsoon land precipitation equatorward, with increased rain over southern Brazil and reduced rain over the La Plata basin. ramifications of this elevated heating heat pump mechanism in aerosol monsoon water cycle on climate variability and change will be discussed. The ramifications of this "elevated heating heat pump" mechanism in aerosol monsoom water cycle on climate

  4. Understanding the Effect of Precession on South American Climate

    NASA Astrophysics Data System (ADS)

    Liu, X.; Battisti, D. S.

    2014-12-01

    The oxygen isotope concentration in calcite (δ18Oc) in speleothems over South America shows a distinct spatial pattern of change for the past 250,000 years orchestrated by precessional forcing. Using an isotope-enabled model (ECHAM4.6) coupled to a slab ocean model, we study how and why precession changes the climate of South America. Two experiments, called the "low insolation" experiment and "high insolation" experiment, were performed with the same modern boundary conditions, but forced with the extreme minimum and maximum of Southern Hemisphere (SH) summer insolation, respectively. Differences between these two experiments ("low" minus "high") display as a dipole pattern: less precipitation and heavier precipitation-weighted δ18O (δ18Op) along the Andes, and more precipitation and lighter δ18Op in northeastern Brazil. The differences in δ18Op are consistent with δ18Oc of speleothems, in terms of both sign and magnitude. Further analysis of the δ18O of precipitation, the δ18O of water vapor and the probability distribution function (pdf) of precipitation intensity reveals that changes in both the seasonality of precipitation and the "amount effect" contribute to the heavier δ18Op along the Andes, while the "amount effect" almost exclusively contributes to the lighter δ18Op in northeastern Brazil. To identify the causes of precipitation response, three additional experiments are performed with localized albedo increase over South America and/or Africa. These show that the decrease in precipitation along the Andes is caused by cooling of South American continent, whereas the increase in precipitation over northeastern Brazil is associated with cooling of northern Africa. Reduction of SH summer insolation cools both South America and northern Africa. Cooling of South America weakens the South American summer monsoon (SASM) and changes the pdf of precipitation intensity over tropical South America and along the Andes; contrary to previous suggestions

  5. Comparison of North and South American biomes from AVHRR observations

    NASA Technical Reports Server (NTRS)

    Goward, Samuel N.; Dye, Dennis; Kerber, Arlene; Kalb, Virginia

    1987-01-01

    Previous analysis of the North American continent with AVHRR-derived vegetation index measurements showed a strong relation between known patterns of vegetation seasonality, productivity and the spectral vegetation index measurements. This study extends that analysis to South America to evaluate the degree to which these findings extend to tropical regions. The results show that the spectral vegetation index measurements provide a general indicator of vegetation activity across the major biomes of the Western Hemisphere of the earth, including tropical regions. The satellite-observed patterns are strongly related to the known climatology of the continents and may offer a means to improve understanding of global bioclimatology. For example, South America is shown to have a longer growing season with much earlier spring green-up than North America. The time integral of the measurements, computed from 12 composited monthly values, produces a value that is related to published net primary productivity data. However, limited net primary production data does not allow complete evaluation of satellite-observed contrasts between North and South American biomes. These results suggest that satellite-derived spectral vegetation index measurements are of great potential value in improving knowledge of the earth's biosphere.

  6. Influence of Andean Plateau Rise on South American Climate Dynamics

    NASA Astrophysics Data System (ADS)

    Insel, N.; Poulsen, C. J.; Ehlers, T. A.

    2008-12-01

    Large mountain ranges exhibit a first-order control on climate. In South America, the modern Andes act as a barrier to atmospheric flow and control regional wind and precipitation patterns. However, it is unclear how climate may have changed over time as Andean topography developed. We present results from a regional general circulation model (RegCM3) to evaluate dynamical and physical atmospheric changes associated with variations in Andean plateau height during the Cenozoic. A series of five experiments were conducted with plateau topography systematically varying between 0 and 100% of the modern. Experiments were performed over a continental-scale domain with 60km horizontal resolution using the MIT-Emanuel convection scheme. Land surface characteristics, sea-surface temperatures and atmospheric boundary conditions were specified from modern NCEP reanalysis data. Model results show that large-scale upper-level (200 mbar) circulation characteristics are only weakly affected by the removal of the Andes with a slight weakening and eastward shift of the high pressure system over Bolivia. However, low-level (800 mbar) wind patterns change significantly and have a direct effect on precipitation in South America. The following features can be observed as the Andean topography decreases: (1) The dominant wind direction in the central Andes reverses with prevailing winds sourced from the Pacific Ocean. The Westerlies are characterized by low moisture content due to the presence of the cold Humboldt current along the west coast of South America. (2) A reduction in the surface pressure gradient between the Andes and the Amazon Basin reduces convergence over the plateau and suppresses the South American low level jet, reducing the southward moisture flux along the eastern flanks of the Andes that is the primary source for precipitation in the Chaco region. These changes lead to declines in precipitation over the Andes and decreased latent heat release. This results in a

  7. Desi Women on the Forty Acres: Exploring Intergenerational Issues and Identity Development of South Asian American College Students

    ERIC Educational Resources Information Center

    Ruzicka, Smita Sundaresan

    2011-01-01

    South Asian Americans are one of the fastest growing sub-groups within the Asian American population in the United States today. Between 1960 and 1990, the South Asian American population witnessed an increase of approximately 900% (Leonard, 1997). This increase in population also corresponds with the increase in South Asian American students…

  8. Y-chromosome lineages in native South American population.

    PubMed

    Blanco-Verea, A; Jaime, J C; Brión, M; Carracedo, A

    2010-04-01

    The present work tries to investigate the population structure and variation of the Amerindian indigenous populations living in Argentina. A total of 134 individuals from three ethnic groups (Kolla, Mapuche and Diaguitas) living in four different regions were collected and analysed for 26 Y-SNPs and 11 Y-STRs. Intra-population variability was analysed, looking for population substructure and neighbour populations were considered for genetic comparative analysis, in order to estimate the contribution of the Amerindian and the European pool, to the current population. We observe a high frequency of R1b1 and Q1a3a* Y-chromosome haplogroups, in the ethnic groups Mapuche, Diaguita and Kolla, characteristic of European and Native American populations, respectively. When we compare our native Argentinean population with other from the South America we also observe that frequency values for Amerindian lineages are relatively lower in our population. These results show a clear Amerindian genetic component but we observe a predominant European influence too, suggesting that typically European male lineages have given rise to the displacement of genuinely Amerindian male lineages in our South American population. PMID:20215030

  9. South American foF2 database using genetic algorithms

    NASA Astrophysics Data System (ADS)

    Gularte, Erika; Bilitza, Dieter; Carpintero, Daniel; Jaen, Juliana

    2016-07-01

    We present the first step towards a new database of the ionospheric parameter foF2 for the South American region. The foF2 parameter, being the maximum of the ionospheric electronic density profile and its main sculptor, is of great interest not only in atmospheric studies but also in the realm of radio propagation. Due to its importance, its large variability and the difficulty to model it in time and space, it was the subject of an intense study since decades ago. The current databases, used by the IRI (International Reference Ionosphere) model, and based on Fourier expansions, has been built in the 60s from the available ionosondes at that time; therefore, it is still short of South American data. The main goal of this work is to upgrade the database, incorporating the now available data compiled by the RAPEAS (Red Argentina para el Estudio de la Atmósfera Superior, Argentine Network for the Study of the Upper Atmosphere) network. Also, we developed an algorithm to study the foF2 variability, based on the modern technique of genetic algorithms, which has been successfully applied on other disciplines. One of the main advantages of this technique is its ability in working with many variables and with unfavorable samples. The results are compared with the IRI databases, and improvements to the latter are suggested. Finally, it is important to notice that the new database is designed so that new available data can be easily incorporated.

  10. Influence of subduction history on South American topography

    NASA Astrophysics Data System (ADS)

    Flament, Nicolas; Gurnis, Michael; Müller, R. Dietmar; Bower, Dan J.; Husson, Laurent

    2015-11-01

    The Cenozoic evolution of South American topography is marked by episodes of large-scale uplift and subsidence not readily explained by lithospheric deformation. The drying up of the inland Pebas system, the drainage reversal of the Amazon river, the uplift of the Sierras Pampeanas and the uplift of Patagonia have all been linked to the evolution of mantle flow since the Miocene in separate studies. Here we investigate the evolution of long-wavelength South American topography as a function of subduction history in a time-dependent global geodynamic model. This model is shown to be consistent with these inferred changes, as well as with the migration of the Chaco foreland basin depocentre, that we partly attribute to the inboard migration of subduction resulting from Andean mountain building. We suggest that the history of subduction along South America has had an important influence on the evolution of the topography of the continent because time-dependent mantle flow models are consistent with the history of vertical motions as constrained by the geological record at four distant areas over a whole continent. Testing alternative subduction scenarios reveals flat slab segments are necessary to reconcile inferred Miocene shorelines with a simple model paleogeography. As recently suggested, we find that the flattening of a subduction zone results in dynamic uplift between the leading edge of the flat slab segment and the trench, and in a wave of dynamic subsidence associated with the inboard migration of the leading edge of flat subduction. For example, the flattening of the Peruvian subduction contributed to the demise of Pebas shallow-water sedimentation, while continental-scale tilting also contributed to the drainage reversal of the Amazon River. The best correlation to P-wave tomography models for the Peruvian flat slab segment is obtained for a case when the asthenosphere, here considered to be 150 km thick and 10 times less viscous than the upper mantle, is

  11. Checklist of the helminth parasites of South American bats.

    PubMed

    Santos, Cláudia Portes; Gibson, David I

    2015-01-01

    Although the Chiroptera represents a significant proportion (c.20%) of the mammalian fauna and South America has the highest diversity of bat species, only about a third of the known species in this region have had helminth parasites reported from them. This work represents the first comprehensive checklist of the helminth parasites (nematodes, acanthocephalans, trematodes and cestodes) of South American bats. The data were extracted from more than 120 references and are presented as a key to each group of parasites down to the generic level, with an indication of how the bats become infected, accompanied by a list of the species recorded for each genus. This is followed, in tabular form, by parasite-host and host-parasite checklists. The parasite-host list also includes their geographical distribution in South America (at the country level) and site data, plus the references in which the parasite records occur. The host-parasite list is arranged according to the classification of the hosts. In all, c.370 host-parasite associations are recorded, involving 114 nominal species of helminths from 92 named chiropteran taxa. PMID:25947481

  12. Pollution and its Impacts on the South American Cryosphere

    NASA Astrophysics Data System (ADS)

    Molina, Luisa T.; Gallardo, Laura; Andrade, M.; Baumgardner, D.; Borbor-Córdova, M.; Bórquez, R.; Casassa, G.; Cereceda-Balic, F.; Dawidowski, L.; Garreaud, R.; Huneeus, N.; Lambert, F.; McCarty, J. L.; Mc Phee, J.; Mena-Carrasco, M.; Raga, G. B.; Schmitt, C.; Schwarz, J. P.

    2015-12-01

    This article is a review of the science goals and activities initiated within the framework of the Pollution and its Impacts on the South American Cryosphere (PISAC) initiative. Air pollution associated with biomass burning and urban emissions affects extensive areas of South America. We focus on black carbon (BC) aerosol and its impacts on air quality, water availability, and climate, with an emphasis on the Andean cryosphere. BC is one of the key short-lived climate pollutants that is a topic of growing interest for near-term mitigation of these issues. Limited scientific evidence indicates that the Andean cryosphere has already responded to climate change with receding glaciers and snow cover, which directly affect water resources, agriculture, and energy production in the Andean region of South America. Despite the paucity of systematic observations along the Andes, a few studies have detected BC on snow and glaciers in the Andes. These, in addition to existing and projected emissions and weather patterns, suggest a possible contribution of BC to the observed retreat of the Andean cryosphere. Here we provide an overview of the current understanding of these issues from scientific and policy perspectives, and propose strategic expansions to the relevant measurement infrastructure in the region.

  13. Changes in South American Monsoon During the Holocene

    NASA Astrophysics Data System (ADS)

    Turcq, B.; Albuquerque, A. S.; Braconnot, P.; Cordeiro, R. C.; Jorgetti, T.; Khodri, M.; Sifeddine, A.; Silva Dias, M. F.; Silva Dias, P. L.

    2006-12-01

    The main feature of South American Monsoon is the precipitations associated to the South Atlantic Convergence Zone (SACZ). The SACZ occurs during SH summer and consists in an organisation of convective activity along a northwest-southeast axis from the main convection region in western Amazonia to the Southeast region of Brazil and adjacent Atlantic Ocean. Several paleoclimate data indicate reduced precipitations in the ZCAS influence zone during the Early and Middle Holocene whereas there are some signals of wetter climate in Northeast Brazil and in the southern part of central Brazil. The simulation of 6k climate by the IPSL coupled Ocean Atmosphere GCM suggests some mechanisms to explain these regional differences: (1) the reduced summer insolation provoked a decrease of SACZ activity (2) the SH summer position of ITCZ is displaced southward explaining a wetter climate in northeast Brazil (3) the analysis of the transient meridional heat transport and of the baroclinicity of the model climate suggests more intense winter and early spring cold outbreaks in the central region of South America, also in agreement with the data from south central Brazil. This last mechanism may be enhanced by vegetation feedback. However, in the ZCAS influence region the model indicate an increase in rainfalls during spring that compensates the summer decrease leading to few changes in annual rainfalls. Such a pattern is also observed in other GCM simulations but is not in agreement with the proxydata which indicate lower levels of the lakes and an opening of the Atlantic rainforest toward a mosaic of Savannas and Gallery Forests during Early and Middle Holocene.

  14. 78 FR 50135 - CNC Development, Ltd., Exousia Advanced Materials, Inc., and South American Minerals, Inc.; Order...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-16

    ... From the Federal Register Online via the Government Publishing Office SECURITIES AND EXCHANGE COMMISSION CNC Development, Ltd., Exousia Advanced Materials, Inc., and South American Minerals, Inc.; Order... current and accurate information concerning the securities of South American Minerals, Inc. because it...

  15. Exploring Hybrid Identities: South Asian American Women Pursue a Career in Teaching

    ERIC Educational Resources Information Center

    Shah, Amita Roy

    2013-01-01

    This study explores how second-generation South Asian American women negotiated their hybrid identities to pursue a career in teaching. Many South Asian Americans have not pursued a career in teaching because of various external and internal factors that have influenced their sense of identity, academic achievement, and professional career path…

  16. South American Monsoon and the Land Surface Processes

    NASA Astrophysics Data System (ADS)

    Xue, Y.; de Sales, F. H.; Li, W.; Mechoso, C. R.; Nobre, C. A.; Juang, H. H.

    2002-12-01

    In this numerical modeling study, the NCEP GCM is applied to investigate the interactions between land surface processes and climate, particularly the effects of land processes on the South American monsoon system (SAMS). A model version with spectral triangular 42 truncation (T42) is used. The corresponding Gaussian grid for T42 is 128 by 64, which is roughly equivalent to 2.8 degrees in latitude and longitude. Two land surface parameterizations are used. One is the Simplified Simple Biosphere Model (SSiB), which includes explicit vegetation representation. The other parameterization is a surface model with two-soil layers (SOIL) and no explicit vegetation scheme. Two 12-month long simulations were performed with the two parameterizations from initial conditions corresponding to May 1, 1987 and identical distributions of soil moisture and surface albedo. The simulations will be referred to as NCEP GCM/SOIL and NCEP GCM/SSiB. The simulations, therefore, differ in the land surface parameterizations and land cover conditions: one with vegetation and the other with only soil layers (but monthly mean vegetation albedo). This experiment aims to test the role of explicit description of vegetation process in the climate model and hence the role of vegetation in the South American hydrometeorology. SAMS starts developing in Central America and then moves southeast towards the Amazons in South America. Afterwards, largest precipitation moves northward and eventually retreats northwest. NCEP GCM/SOIL and NCEP GCM/SSiB produce substantially different evolution and spatial distributions of SAMS. In the NCEP GCM/SOIL, the development of SAMS is too fast and too strong with no clear indication of the southward movement. Rainfall magnitudes are much stronger than in the observation. The NCEP/SSiB, on the other hand, correctly simulates SAMS evolution. To understand the mechanisms that contributed to the differences in the simulations, the surface energy and water balances are

  17. Oral paracoccidioidomycosis. A study of 36 South American patients.

    PubMed

    Sposto, M R; Scully, C; de Almeida, O P; Jorge, J; Graner, E; Bozzo, L

    1993-04-01

    Paracoccidioidomycosis (South American blastomycosis) is an uncommon, progressive systemic mycosis, virtually only seen in persons who have visited Latin America. Reports of oral lesions are extremely rare in the English-language literature. Thirty-six adults with oral lesions as the first sign of paracoccidioidomycosis are described; this appears to be the largest series in the dental literature. All had chronic proliferative mulberry-like ulcerated oral lesions; the diagnosis was confirmed histologically. The gingiva or alveolar process was the typical site, but lesions were also seen particularly on the palate and lip. Most of the patients proved to have detectable pulmonary involvement. Patients with lesions in the oropharynx, tongue, or floor of mouth all had confirmed pulmonary lesions. PMID:8464610

  18. Encephalitozoonosis in 2 South American Fur Seal (Arctocephalus australis) Pups

    PubMed Central

    Seguel, M.; Howerth, E. W.; Ritter, J.; Paredes, E.; Colegrove, K.; Gottdenker, N.

    2015-01-01

    Cerebral and disseminated encephalitozoonosis was diagnosed by histopathology, electron microscopy, and immunohistochemistry in 2 free-ranging South American fur seal pups found dead at Guafo Island (43°33′S 74°49′W) in southern Chile. In the brain, lesions were characterized by random foci of necrosis with large numbers of macrophages containing numerous microsporidial organisms within parasitophorous vacuoles. In addition, occasional histiocytes loaded with numerous mature and immature microsporidia spores consistent with Encephalitozoon sp were observed in pulmonary alveolar septa, splenic red pulp, glomerular capillaries, and proximal renal tubules by Gram and immunohistochemical stains. To our knowledge, microsporidial infection in a marine mammal species has not been previously reported. PMID:25248519

  19. Encephalitozoonosis in 2 South American Fur Seal (Arctocephalus australis) Pups.

    PubMed

    Seguel, M; Howerth, E W; Ritter, J; Paredes, E; Colegrove, K; Gottdenker, N

    2015-07-01

    Cerebral and disseminated encephalitozoonosis was diagnosed by histopathology, electron microscopy, and immunohistochemistry in 2 free-ranging South American fur seal pups found dead at Guafo Island (43°33'S 74°49'W) in southern Chile. In the brain, lesions were characterized by random foci of necrosis with large numbers of macrophages containing numerous microsporidial organisms within parasitophorous vacuoles. In addition, occasional histiocytes loaded with numerous mature and immature microsporidia spores consistent with Encephalitozoon sp were observed in pulmonary alveolar septa, splenic red pulp, glomerular capillaries, and proximal renal tubules by Gram and immunohistochemical stains. To our knowledge, microsporidial infection in a marine mammal species has not been previously reported. PMID:25248519

  20. AIRSAR South American deployment: Operation plan, version 3.0

    NASA Technical Reports Server (NTRS)

    Kobrick, M.

    1993-01-01

    The United States National Aeronautics and Space Administration (NASA) and the Brazilian Commission for Space Activities (COBAE) are undertaking a joint experiment involving NASA's DC-8 research aircraft and the Airborne Synthetic Aperture Radar (AIRSAR) system during late May and June 1993. The research areas motivating these activities are: (1) fundamental research in the role of soils, vegetation, and hydrology in the global carbon cycle; and (2) in cooperation with South American scientists, airborne remote sensing research for the upcoming NASA Spaceborne Imaging Radar (SIR)-C/X-SAR flights on the Space Shuttle. A flight schedule and plans for the deployment that were developed are included. Maps of the site locations and schematic indications of flight routes and dates, plots showing swath locations derived from the flight requests and generated by flight planning software, and, most importantly, a calendar showing which sites will be imaged each day are included.

  1. Gastric carcinoma in a South American sea lion (Otaria flavescens).

    PubMed

    Yamazaki, Mutsumi; Koutaka, Mitsuru; Une, Yumi

    2016-08-01

    A 22-year-old captive male South American sea lion (Otaria flavescens) developed an undifferentiated carcinoma originating in the cardiac region of the stomach. Clinical symptoms included vomiting, anorexia and weight loss. Ultrasonography and endoscopy showed gastric wall thickness. At necropsy, the gastric wall had significant thickening around the cardiac region, and metastases were found in some organs. Histologically, samples from the stomach wall and metastases showed the same tumor tissue. Immunohistochemistry was positive for epithelium markers. Ductal growth, keratinocytes or signet ring cells were absent. The tumor was classified as an undifferentiated carcinoma using the World Health Organization's (WHO) guide to international classification of tumors in domestic animals. This is the first report of a primary gastric carcinoma in a pinniped. PMID:27052463

  2. Gastric carcinoma in a South American sea lion (Otaria flavescens)

    PubMed Central

    YAMAZAKI, Mutsumi; KOUTAKA, Mitsuru; UNE, Yumi

    2016-01-01

    A 22-year-old captive male South American sea lion (Otaria flavescens) developed an undifferentiated carcinoma originating in the cardiac region of the stomach. Clinical symptoms included vomiting, anorexia and weight loss. Ultrasonography and endoscopy showed gastric wall thickness. At necropsy, the gastric wall had significant thickening around the cardiac region, and metastases were found in some organs. Histologically, samples from the stomach wall and metastases showed the same tumor tissue. Immunohistochemistry was positive for epithelium markers. Ductal growth, keratinocytes or signet ring cells were absent. The tumor was classified as an undifferentiated carcinoma using the World Health Organization’s (WHO) guide to international classification of tumors in domestic animals. This is the first report of a primary gastric carcinoma in a pinniped. PMID:27052463

  3. Polycyclic aromatic hydrocarbons in the South American environment.

    PubMed

    Barra, Ricardo; Castillo, Caroline; Torres, Joao Paulo Machado

    2007-01-01

    Pollution of the environment with polycyclic aromatic hydrocarbons (PAHs) should be a global concern, especially in urbanized areas. In South American countries, where notable increase in urban populations has been observed in the past few years, reliable information about the pollution status of these urban environments is not always easily accessible, and therefore an effort to collect updated information is required. This review attempts to contribute by analyzing the existing information regarding environmental levels of PAHs in some South American countries. A regional trend for environmental PAH information is an uneven contribution, because some countries, such as Bolivia, Peru, Paraguay, and Ecuador, have reported no information at all in the scientific literature, reflecting to a certain extent the different patterns of economic, technical, and scientific development. PAH air monitoring is one of the areas that has received the most attention during the last few years, mainly in Brazil, Chile, and Argentina, where data represent a few geographical areas within the region. PAH levels in air from some urban areas in Argentina, Brazil, and Chile, considered moderate to high (100-1000ng/m3), are probably among the highest values reported in the open literature. Urbanization, vehicle pollution, and wood fires are the principal contributors to the high reported levels. In more temperate areas, a clear distinction is observed between summer and winter levels. PAH monitoring in soils is very limited within the region, with few data available, and most information indicates widespread pollution. In Brazil, values for many representative ecosystems were found. In Chile, data from forestry and agricultural areas indicate in general low concentrations, in spite of a relatively high detection frequency. Pollution levels in soils are highly dependent on their closeness to PAH sources and certain cultural practices (agricultural burnings, forest fires, etc.). Water PAH

  4. Male lineages in South American native groups: evidence of M19 traveling south.

    PubMed

    Toscanini, Ulises; Gusmão, Leonor; Berardi, Gabriela; Gomes, Verónica; Amorim, António; Salas, Antonio; Raimondi, Eduardo

    2011-10-01

    With this study, we aimed to determine the different male ancestral components of two Native American communities from Argentina, namely Toba and Colla. The analysis of 27 Y-chromosome SNPs allowed us to identify seven different haplogroups in both samples. Chromosomes carrying the M3 mutation, which typically defines the Native American haplogroup Q1a3a, were seen most frequently in the Toba community (90%). Conversely, Q1a3a was represented in 34% of the Colla Y-chromosomes, whereas haplogroup R1b1, the main representative of western European populations, exhibited the highest frequency in this population (41%). Different M3 sublineages in the Toba community could be identified by observing point mutations at both DYS385 and M19 loci. A microvariant at DYS385, named 16.1, has been characterized, which helps to further subdivide Q1a3a. It is the first time the M19 mutated allele is described in a population from Argentina. This finding supports the old age of the lineages carrying the M19 mutation, but it contradicts the previous hypothesis that the M19 mutated allele is confined to only two Equatorial-Tucano population groups from the north region of South America. The detection of M19 further south than previously thought allows questioning of the hypothesis that this lineage serves as an example of isolation after colonization. This observation also affirms the strong genetic drift to which Native Americans have been subjected. Moreover, our study illustrates a heterogeneous contribution of Europeans to these populations and supports previous studies showing that most Native American groups were subjected to European admixture that primarily involved immigrant men. PMID:21826635

  5. Learning from the Margins: The Education of Southeast and South Asian Americans in Context

    ERIC Educational Resources Information Center

    Ngo, Bic

    2006-01-01

    This article explicates the diversity within the Asian American community by focusing on Southeast and South Asian American students. Focusing on these two groups is important given their recent migration (relative to other groups) and tenuous position within Asian American research, discourse, and representation. In particular, this article…

  6. Netizenship Politics: Youth, Anti-Americanism, and Rhetorical Agency in South Korea's 2002 Candlelight Vigils

    ERIC Educational Resources Information Center

    Kang, Jiyeon

    2009-01-01

    This study offers a rhetorical analysis of the 2002 South Korean Candlelight Vigils ["ch'otpul siwi"] with a focus on the role of the Internet in public opinion building, the rise in anti-American sentiment in South Korea, and rhetorical agency residing in the collective. In 2002, two South Korean schoolgirls walking along a rural road near Seoul…

  7. Intraspecific variability and systematics in South American Syrotrigoniinae (Trigoniida, Bivalvia)

    NASA Astrophysics Data System (ADS)

    Echevarría, Javier; Damborenea, Susana E.; Manceñido, Miguel O.

    2015-04-01

    The systematics of the genus Syrotrigonia is revised in the light of the intraspecific variability of a large sample of Syrotrigonia sigeli from the Valanginian from Neuquén Basin, Argentina. The genus can be recognized by the presence of concentric or subconcentric costae surrounding the umbo, later on developing an inflection and finally resulting in a set of anterior horizontal to commarginal costae and another set of posterior sub-vertical costae. The anterior part of the area bears transverse, usually anteriorly concave, costae which direct towards the umbo on the escutcheon; initially they are continuous with those on the flank, but later on they usually alternate. General shell shape, the presence of an antecarinal sulcus, the junction pattern between both sets of costae and the number of horizontal costae relative to vertical costae are variable among species, while costae width or density and the development of horizontal vs. commarginal costae may vary highly within species. The presence of commarginal rugae developed on the whole surface of the shell is interpreted as a result of environmental perturbations. A brief biogeographical interpretation of the family Buchotrigoniidae is also outlined. Syrotrigonia probably originated in North America in the Tithonian, being widespread in the Pacific coast of South America by Early Cretaceous times; at least six (probably seven) South American species could be recognized. By Aptian times the taxon reached the Tethyan realm, its last record being Aptian or Albian in age. The frequent presence of different species in marginal marine deposits suggests a euryhaline lineage adapted to salinity variations, this may also be the cause of the frequent presence of commarginal rugae. Considering the high variability displayed in the analyzed material, large samples are needed to characterize new species within the group.

  8. South American Summer Monsoon history recorded in Brazilian speleothems

    NASA Astrophysics Data System (ADS)

    Wang, X.; Auler, A. S.; Edwards, R. L.; Cheng, H.

    2008-12-01

    We have obtained three high-resolution oxygen isotopic records of cave calcites from Caverna Botuverá, southern Brazil, Gruta do Padre, central Brazil, and Caverna Paraíso, Amazonian Brazil. All three records have chronologies determined by U-Th dates and span the last 90, 20 and 50 thousand years, respectively. Tests for equilibrium conditions show that their oxygen isotopic variations are primarily caused by climate change. The three records thus can provide information about precipitation history and fluctuations of the South American Summer Monsoon along a latitudinal transect from 28° S to 4° S. During the last glacial period, the three oxygen isotopic profiles show abrupt millennial-scale variations, which are anti- correlated with the Chinese speleothem monsoon records and northern high-latitude ice core records. This is likely related to the displacement of the mean position of the intertropical convergence zone and associated asymmetry of Hadley cells, consistent with an oceanic meridional overturning circulation mechanism for driving the abrupt climate events. However, the three records show distinct isotopic patterns in Holocene epoch. The δ18O values in the Botuvera record decrease steadily throughout Holocene, while in the Padre record, the δ18O drops slightly until ~6-7 thousand years ago and then gradually increases until the present. The Paraiso Holocene record is similar to the Padre one, but with a much greater amplitude. Together with Andean ice core and lake records, our observations suggest asynchronous changes in Holocene monsoonal precipitation in South America, possibly related to strengthened zonal tropical air-sea interactions after the melting of the large northern ice sheets.

  9. Semen preservation and artificial insemination in domesticated South American camelids.

    PubMed

    Bravo, P Walter; Alarcon, V; Baca, L; Cuba, Y; Ordoñez, C; Salinas, J; Tito, F

    2013-01-10

    Semen preservation and artificial insemination in South American camelids are reviewed giving emphasis to work done in Peru and by the authors. Reports on semen evaluation and the preservation process indicate that semen of alpacas and llamas can be manipulated by making it liquid first. Collagenase appears to be the best enzyme to eliminate viscosity. Tris buffer solution maintains a higher motility than egg-yolk citrate, phosphate buffered saline (PBS), Triladyl, and Merck-I extenders. Cooling of semen took 1h after collected, and equilibrated with 7% glycerol presented a better motility and spermatozoa survival at 1, 7, 15 and 30days after being slowly frozen in 0.25mL plastic straws. Trials of artificial insemination with freshly diluted semen and frozen-thawed semen are encouraging and needs to be tested extensively under field conditions. Recently, fertility rates varied from 3 to 67%. Semen preservation and most important, artificial insemination appear to be a reality, and could be used to improve the genetic quality of alpacas and llamas. PMID:23153624

  10. Antiviral activity of some South American medicinal plants.

    PubMed

    Abad, M J; Bermejo, P; Sanchez Palomino, S; Chiriboga, X; Carrasco, L

    1999-03-01

    Folk medicinal plants are potential sources of useful therapeutic compounds including some with antiviral activities. Extracts prepared from 10 South American medicinal plants (Baccharis trinervis, Baccharis teindalensis, Eupatorium articulatum, Eupatorium glutinosum, Tagetes pusilla, Neurolaena lobata, Conyza floribunda, Phytolacca bogotensis, Phytolacca rivinoides and Heisteria acuminata) were screened for in vitro antiviral activity against herpes simplex type I (HSV-1), vesicular stomatitis virus (VSV) and poliovirus type 1. The most potent inhibition was observed with an aqueous extract of B. trinervis, which inhibited HSV-1 replication by 100% at 50-200 micrograms/mL, without showing cytotoxic effects. Good activities were also found with the ethanol extract of H. acuminata and the aqueous extract of E. articulatum, which exhibited antiviral effects against both DNA and RNA viruses (HSV-1 and VSV, respectively) at 125-250 micrograms/mL. The aqueous extracts of T. pusilla (100-250 micrograms/mL), B. teindalensis (50-125 micrograms/mL) and E. glutinosum (50-125 micrograms/mL) also inhibited the replication of VSV, but none of the extracts tested had any effect on poliovirus replication. PMID:10190189

  11. Deforestation changes land-atmosphere interactions across South American biomes

    NASA Astrophysics Data System (ADS)

    Salazar, Alvaro; Katzfey, Jack; Thatcher, Marcus; Syktus, Jozef; Wong, Kenneth; McAlpine, Clive

    2016-04-01

    South American biomes are increasingly affected by land use/land cover change. However, the climatic impacts of this phenomenon are still not well understood. In this paper, we model vegetation-climate interactions with a focus on four main biomes distributed in four key regions: The Atlantic Forest, the Cerrado, the Dry Chaco, and the Chilean Matorral ecosystems. We applied a three member ensemble climate model simulation for the period 1981-2010 (30 years) at 25 km resolution over the focus regions to quantify the changes in the regional climate resulting from historical deforestation. The results of computed modelling experiments show significant changes in surface fluxes, temperature and moisture in all regions. For instance, simulated temperature changes were stronger in the Cerrado and the Chilean Matorral with an increase of between 0.7 and 1.4 °C. Changes in the hydrological cycle revealed high regional variability. The results showed consistent significant decreases in relative humidity and soil moisture, and increases in potential evapotranspiration across biomes, yet without conclusive changes in precipitation. These impacts were more significant during the dry season, which resulted to be drier and warmer after deforestation.

  12. South Asian high and Asian-Pacific-American climate teleconnection

    NASA Astrophysics Data System (ADS)

    Zhang, Peiqun; Song, Yang; Kousky, Vernon E.

    2005-11-01

    Growing evidence indicates that the Asian monsoon plays an important role in affecting the weather and climate outside of Asia. However, this active role of the monsoon has not been demonstrated as thoroughly as has the variability of the monsoon caused by various impacting factors such as sea surface temperature and land surface. This study investigates the relationship between the Asian monsoon and the climate anomalies in the Asian-Pacific-American (APA) sector. A hypothesis is tested that the variability of the upper-tropospheric South Asian high (SAH), which is closely associated with the overall heating of the large-scale Asian monsoon, is linked to changes in the subtropical western Pacific high (SWPH), the mid-Pacific trough, and the Mexican high. The changes in these circulation systems cause variability in surface temperature and precipitation in the APA region. A stronger SAH is accompanied by a stronger and more extensive SWPH. The enlargement of the SWPH weakens the mid-Pacific trough. As a result, the southern portion of the Mexican high becomes stronger. These changes are associated with changes in atmospheric teleconnections, precipitation, and surface temperature throughout the APA region. When the SAH is stronger, precipitation increases in southern Asia, decreases over the Pacific Ocean, and increases over the Central America. Precipitation also increases over Australia and central Africa and decreases in the Mediterranean region. While the signals in surface temperature are weak over the tropical land portion, they are apparent in the mid latitudes and over the eastern Pacific Ocean.

  13. The Impact of the Great Migration on Mortality of African Americans: Evidence from the Deep South

    PubMed Central

    Black, Dan A.; Sanders, Seth G.; Taylor, Evan J.

    2015-01-01

    The Great Migration—the massive migration of African Americans out of the rural South to largely urban locations in the North, Midwest, and West—was a landmark event in U.S. history. Our paper shows that this migration increased mortality of African Americans born in the early twentieth century South. This inference comes from an analysis that uses proximity of birthplace to railroad lines as an instrument for migration. PMID:26345146

  14. School Adjustment and the Academic Success of Rural African American Early Adolescents in the Deep South

    ERIC Educational Resources Information Center

    Farmer, Thomas W.; Irvin, Matthew J.; Thompson, Jana H.; Hutchins, Bryan C.; Leung, Man-Chi

    2006-01-01

    This study examined the relationship between end-of-year grades and the academic, behavioral, and social characteristics of rural African American youth. Participants included 392 7th and 8th grade students from 2 rural middle schools in the south. Participants were African American and were from 2 communities that have child poverty rates…

  15. The Role of Public Schools in HIV Prevention: Perspectives from African Americans in the Rural South

    ERIC Educational Resources Information Center

    Lloyd, Stacey W.; Ferguson, Yvonne Owens; Corbie-Smith, Giselle; Ellison, Arlinda; Blumenthal, Connie; Council, Barbara J.; Youmans, Selena; Muhammad, Melvin R.; Wynn, Mysha; Adimora, Adaora; Akers, Aletha

    2012-01-01

    Though African-American youth in the South are at high risk for HIV infection, abstinence until marriage education continues to be the only option in some public schools. Using community-based participatory research methods, we conducted 11 focus groups with African-American adults and youth in a rural community in North Carolina with high rates…

  16. English or Perish: How Contemporary South Korea Received, Accommodated, and Internalized English and American Modernity

    ERIC Educational Resources Information Center

    Lee, JongHwa; Han, Min Wha; McKerrow, Raymie E.

    2010-01-01

    This paper discusses the positionality of English in South Korea as a form of symbolic capital that represents the discursive power of Americanism and East Asian Social Darwinism. By employing Bourdieu's and Foucault's theoretical orientations, this paper traces how South Korean linguistic policies to incorporate English loan words coincide with…

  17. Recurrent Evolution of Melanism in South American Felids

    PubMed Central

    Schneider, Alexsandra; Henegar, Corneliu; Day, Kenneth; Absher, Devin; Napolitano, Constanza; Silveira, Leandro; David, Victor A.; O’Brien, Stephen J.; Menotti-Raymond, Marilyn; Barsh, Gregory S.; Eizirik, Eduardo

    2015-01-01

    Morphological variation in natural populations is a genomic test bed for studying the interface between molecular evolution and population genetics, but some of the most interesting questions involve non-model organisms that lack well annotated reference genomes. Many felid species exhibit polymorphism for melanism but the relative roles played by genetic drift, natural selection, and interspecies hybridization remain uncertain. We identify mutations of Agouti signaling protein (ASIP) or the Melanocortin 1 receptor (MC1R) as independent causes of melanism in three closely related South American species: the pampas cat (Leopardus colocolo), the kodkod (Leopardus guigna), and Geoffroy’s cat (Leopardus geoffroyi). To assess population level variation in the regions surrounding the causative mutations we apply genomic resources from the domestic cat to carry out clone-based capture and targeted resequencing of 299 kb and 251 kb segments that contain ASIP and MC1R, respectively, from 54 individuals (13–21 per species), achieving enrichment of ~500–2500-fold and ~150x coverage. Our analysis points to unique evolutionary histories for each of the three species, with a strong selective sweep in the pampas cat, a distinctive but short melanism-specific haplotype in the Geoffroy’s cat, and reduced nucleotide diversity for both ancestral and melanism-bearing chromosomes in the kodkod. These results reveal an important role for natural selection in a trait of longstanding interest to ecologists, geneticists, and the lay community, and provide a platform for comparative studies of morphological variation in other natural populations. PMID:25695801

  18. Successive radiations, not stasis, in the South American primate fauna.

    PubMed

    Hodgson, Jason A; Sterner, Kirstin N; Matthews, Luke J; Burrell, Andrew S; Jani, Rachana A; Raaum, Ryan L; Stewart, Caro-Beth; Disotell, Todd R

    2009-04-01

    The earliest Neotropical primate fossils complete enough for taxonomic assessment, Dolichocebus, Tremacebus, and Chilecebus, date to approximately 20 Ma. These have been interpreted as either closely related to extant forms or as extinct stem lineages. The former hypothesis of morphological stasis requires most living platyrrhine genera to have diverged before 20 Ma. To test this hypothesis, we collected new complete mitochondrial genomes from Aotus lemurinus, Saimiri sciureus, Saguinus oedipus, Ateles belzebuth, and Callicebus donacophilus. We combined these with published sequences from Cebus albifrons and other primates to infer the mitochondrial phylogeny. We found support for a cebid/atelid clade to the exclusion of the pitheciids. Then, using Bayesian methods and well-supported fossil calibration constraints, we estimated that the platyrrhine most recent common ancestor (MRCA) dates to 19.5 Ma, with all major lineages diverging by 14.3 Ma. Next, we estimated catarrhine divergence dates on the basis of platyrrhine divergence scenarios and found that only a platyrrhine MRCA less than 21 Ma is concordant with the catarrhine fossil record. Finally, we calculated that 33% more change in the rate of evolution is required for platyrrhine divergences consistent with the morphologic stasis hypothesis than for a more recent radiation. We conclude that Dolichocebus, Tremacebus, and Chilecebus are likely too old to be crown platyrrhines, suggesting they were part of an extinct early radiation. We note that the crown platyrrhine radiation was concomitant with the radiation of 2 South American xenarthran lineages and follows a global temperature peak and tectonic activity in the Andes. PMID:19321426

  19. Rainwater harvesting in the South American Dry Chaco

    NASA Astrophysics Data System (ADS)

    Magliano, P. N.; Baldi, G.; Murray, F.; Aurand, S.; Paez, R. A.; Jobbagy, E. G.

    2014-12-01

    A vast fraction of the South American Dry Chaco ecoregion still relies on rainwater harvesting (RWH) to support, not only livestock production, but domestic and industrial uses as well. As a result, water capture and storage infrastructure is widely disseminated throughout the region. In this work we characterized the most typical RWH systems in two contrastingly developed sub-regions of Dry Chaco ranging from extensive ranching to intensive beef and dairy production (central Argentina and western Paraguay, respectively). In each sub-region, we quantified RWH density, spatial distribution and associations with landscape features; by other hand, we illustrated how the daily dynamic of water stock in a typical RWH system contributes to assess their capture and storage efficiency. We found that randomly distributed, low-tech RWH systems prevail in central Argentina, while clustered and hi-tech systems do it in western Paraguay. Their density was highly contrasting between sub-regions (0.098 vs. 0.94 units/ km2 in central Argentina and western Paraguay, respectively), being exponentially associated with land cleared fraction and proximity to villages. The daily monitoring of water level suggested a positive but complex response of water capture to precipitation. The elongated catchment area, created by roads and trails, could have partially decoupled local precipitation and water yield of the impoundment, favouring the capture of remote precipitation events and generating highly variable water yield under large local precipitation events. Once stored, the rates of water level decline suggested that infiltration exceeded evaporation as a water output pathway (59 vs. 41%, respectively, of total losses). Across both study areas, RWH accounts for less than 1% of the annual precipitation, playing a minor role on the regional water balance; however at a local level, they can affect several hydrological fluxes including the onset of groundwater recharge and the mitigation of

  20. Successive radiations, not stasis, in the South American primate fauna

    PubMed Central

    Hodgson, Jason A.; Sterner, Kirstin N.; Matthews, Luke J.; Burrell, Andrew S.; Jani, Rachana A.; Raaum, Ryan L.; Stewart, Caro-Beth; Disotell, Todd R.

    2009-01-01

    The earliest Neotropical primate fossils complete enough for taxonomic assessment, Dolichocebus, Tremacebus, and Chilecebus, date to approximately 20 Ma. These have been interpreted as either closely related to extant forms or as extinct stem lineages. The former hypothesis of morphological stasis requires most living platyrrhine genera to have diverged before 20 Ma. To test this hypothesis, we collected new complete mitochondrial genomes from Aotus lemurinus, Saimiri sciureus, Saguinus oedipus, Ateles belzebuth, and Callicebus donacophilus. We combined these with published sequences from Cebus albifrons and other primates to infer the mitochondrial phylogeny. We found support for a cebid/atelid clade to the exclusion of the pitheciids. Then, using Bayesian methods and well-supported fossil calibration constraints, we estimated that the platyrrhine most recent common ancestor (MRCA) dates to 19.5 Ma, with all major lineages diverging by 14.3 Ma. Next, we estimated catarrhine divergence dates on the basis of platyrrhine divergence scenarios and found that only a platyrrhine MRCA less than 21 Ma is concordant with the catarrhine fossil record. Finally, we calculated that 33% more change in the rate of evolution is required for platyrrhine divergences consistent with the morphologic stasis hypothesis than for a more recent radiation. We conclude that Dolichocebus, Tremacebus, and Chilecebus are likely too old to be crown platyrrhines, suggesting they were part of an extinct early radiation. We note that the crown platyrrhine radiation was concomitant with the radiation of 2 South American xenarthran lineages and follows a global temperature peak and tectonic activity in the Andes. PMID:19321426

  1. Antarctica: Arena for South American Cooperation or Conflict.

    ERIC Educational Resources Information Center

    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.…

  2. 75 FR 70897 - Notice of Request for Extension of Approval of an Information Collection; South American Cactus...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-19

    ... Collection; South American Cactus Moth; Quarantine and Regulations AGENCY: Animal and Plant Health Inspection... regulations for the interstate movement of regulated articles to prevent the spread of South American cactus... American cactus moth, contact Dr. Robyn Rose, Program Manager, Emergency and Domestic Programs, PPQ,...

  3. Raising the Quality of Primary Level Mathematics Teaching and Learning in Schools in American Samoa: A Model for South Africa

    ERIC Educational Resources Information Center

    Muthukrishna, Nithi

    2013-01-01

    Against the background of concerns around teaching and learning outcomes in primary school mathematics in South Africa, this article presents two studies conducted in American Samoa and seeks to draw implications for the teaching and learning of mathematics in South Africa. American Samoa has a very similar educational context to South Africa. The…

  4. Differentiation and healthy family functioning of Koreans in South Korea, South Koreans in the United States, and White Americans.

    PubMed

    Kim, Hyejin; Prouty, Anne M; Smith, Douglas B; Ko, Mei-Ju; Wetchler, Joseph L; Oh, Jea-Eun

    2015-01-01

    Inconsistent results have been found in prior research on the Bowen Family Systems Theory concept of differentiation of self and its application to individuals, couples, and families of different cultural backgrounds. In this regard, this study examined the impact of differentiation of self on healthy family functioning, family communication, and family satisfaction with 277 participants including South Koreans living in South Korea, South Korean-born citizens living in the United States, and White Americans living in the United States. Multigroup confirmatory factor analysis identified the measurement invariance of a differentiation scale (DSI-R) used for the three study groups. An analysis of covariance (ANCOVA) found significant differences between White Americans and South Koreans with regard to the level of differentiation. Results of multigroup structural equation modeling (SEM) analyses found a significant association between differentiation of self and healthy family functioning across the three groups with the American group having significantly higher differentiation than the two South Korean groups." Implications for clinical practice and future research are discussed. PMID:24750125

  5. Growth of Mexican-American Children in South Texas.

    ERIC Educational Resources Information Center

    Guinn, Bobby; Crofts, Alfred

    Height, weight, and triceps skinfold were measured in 1,680 Mexican American children, 10 through 14 years of age, from the Lower Rio Grande Valley (LRGV) region of Texas. Study sample measurements were compared to those gathered in 1972 involving LRGV Mexican American children as well as National Center for Health Statistics (NCHS) reference data…

  6. The South American Monsoon Variability over the Last Millennium in CMIP5/PMIP3 simulations

    NASA Astrophysics Data System (ADS)

    Rojas, M.; Arias, P. A.; Flores-Aqueveque, V.; Seth, A.; Vuille, M.

    2015-12-01

    In this paper we assess South American Monsoon System (SAMS) variability throughout the Last Millennium as depicted by the Coupled Modelling Intercomparison Project version 5/Paleo Modelling Intercomparison Project version 3 (CMIP5/PMIP3) simulations. High-resolution proxy records for the South American monsoon over this period show a coherent regional picture of a weak monsoon during the Medieval Climate Anomaly period and a stronger monsoon during the Little Ice Age (LIA). Due to the small forcing during the past 1000 years, CMIP5/PMIP3 model simulations do not show very strong temperature anomalies over these two specific periods, which in turn do not translate into clear precipitation anomalies, as suggested by rainfall reconstructions in South America. However, with an ad-hoc definition of these two periods for each model simulation, several coherent large-scale atmospheric circulation anomalies were identified. The models feature a stronger Monsoon during the LIA associated with: (i) an enhancement of the rising motion in the SAMS domain in austral summer, (ii) a stronger monsoon-related upper-troposphere anticyclone, (iii) activation of the South American dipole, which results to a certain extent in a poleward shift in the South Atlantic Convergence Zone and (iv) a weaker upper-level sub tropical jet over South America, this providing important insights into the mechanisms of these climate anomalies over South America during the past millennium.

  7. Barriers to Clinical Trial Participation: Comparing Perceptions and Knowledge of African American and White South Carolinians.

    PubMed

    Kim, Sei-Hill; Tanner, Andrea; Friedman, Daniela B; Foster, Caroline; Bergeron, Caroline

    2015-01-01

    Analyzing data from a survey of African American and White residents in South Carolina, this study attempts to understand how to better promote clinical trial participation specifically within the African American population. To explore why participation is lower in the African American population, the authors examined two sets of potential barriers: structural/procedural (limited accessibility, lack of awareness, doctors not discussing clinical trial options, lack of health insurance) and cognitive/psychological (lack of subjective and factual knowledge, misperceptions, distrust, fear, perceived risk). Findings revealed that African Americans were significantly less willing than Whites to participate in a clinical trial. African Americans also had lower subjective and factual knowledge about clinical trials and perceived greater risk involved in participating in a clinical trial. The authors found that lack of subjective knowledge and perceived risk were significant predictors of African Americans' willingness to participate in a clinical trial. Implications of the findings are discussed in detail. PMID:26042496

  8. Host-specificity of myxoma virus: Pathogenesis of South American and North American strains of myxoma virus in two North American lagomorph species.

    PubMed

    Silvers, L; Barnard, D; Knowlton, F; Inglis, B; Labudovic, A; Holland, M K; Janssens, P A; van Leeuwen, B H; Kerr, P J

    2010-03-24

    The pathogenesis of South American and North American myxoma viruses was examined in two species of North American lagomorphs, Sylvilagus nuttallii (mountain cottontail) and Sylvilagus audubonii (desert cottontail) both of which have been shown to have the potential to transmit the South American type of myxoma virus. Following infection with the South American strain (Lausanne, Lu), S. nuttallii developed both a local lesion and secondary lesions on the skin. They did not develop the classical myxomatosis seen in European rabbits (Oryctolagus cuniculus). The infection at the inoculation site did not resolve during the 20-day time course of the trial and contained transmissible virus titres at all times. In contrast, S. audubonii infected with Lu had very few signs of disseminated infection and partially controlled virus replication at the inoculation site. The prototype Californian strain of myxoma virus (MSW) was able to replicate at the inoculation site of both species but did not induce clinical signs of a disseminated infection. In S. audubonii, there was a rapid response to MSW characterised by a massive T lymphocyte infiltration of the inoculation site by day 5. MSW did not reach transmissible titres at the inoculation site in either species. This might explain why the Californian myxoma virus has not expanded its host-range in North America. PMID:19836172

  9. Biological relationship between Central and South American Chibchan speaking populations: evidence from mtDNA.

    PubMed

    Melton, Phillip E; Briceño, I; Gómez, A; Devor, E J; Bernal, J E; Crawford, M H

    2007-05-01

    We examined mitochondrial DNA (mtDNA) haplogroup and haplotype diversity in 188 individuals from three Chibchan (Kogi, Arsario, and Ijka) populations and one Arawak (Wayuú) group from northeast Colombia to determine the biological relationship between lower Central American and northern South American Chibchan speakers. mtDNA haplogroups were obtained for all individuals and mtDNA HVS-I sequence data were obtained for 110 samples. Resulting sequence data were compared to 16 other Caribbean, South, and Central American populations using diversity measures, neutrality test statistics, sudden and spatial mismatch models, intermatch distributions, phylogenetic networks, and a multidimensional scaling plot. Our results demonstrate the existence of a shared maternal genetic structure between Central American Chibchan, Mayan populations and northern South American Chibchan-speakers. Additionally, these results suggest an expansion of Chibchan-speakers into South America associated with a shift in subsistence strategies because of changing ecological conditions that occurred in the region between 10,000-14,000 years before present. PMID:17340631

  10. Trends and variability of the South American hydrological cycle for the last 2000 years

    NASA Astrophysics Data System (ADS)

    Evangelista, Heitor; Gonzalez Arango, Catalina; Nogueira, Juliana; Monteiro, Leonardo; von Gunten, Lucien; Khodri, Myriam; Neukom, Raphael

    2016-04-01

    The South American continent encloses two of the largest global river basins: The Amazon basin and the La Plata basin. Its hydrological cycle is highly dependent on the water vapour transport advected from tropical-equatorial Atlantic as well as the polar advections. The Pacific Ocean contribution in the continental water budget is largely restricted to the western Andes region. Nevertheless, moderate-to-intense ENSO periods strongly affect more than half of the South American hydrology, influencing the availability of water resources from mountainous regions that are vital to ecosystems and the human economy and wellbeing. Intense droughts and floods observed continentally during the modern epoch have pointed to the need of better understanding the regional climate related issue. Recent paleoclimate advances, especially the creation of high-standard regional proxy record databases, allow describing the South American climate from a new perspective. However, large areas of tropical South America are still underrepresented in those databases. Here we present an effort of the South American PAGES 2k paleo-community LOTRED-SA to fill this gap. The group aims at producing a South American hydro-climate reconstruction from 267 proxy records (mostly tree rings, ice cores, pollen, instrumental precipitation and river flow) and 14 high resolved speleothems data covering the common era. For this study we plan to reanalyse new and existing tree ring and pollen data with respect to instrumental climate data. The well calibrated tree-ring index will be compared to an independently developed hydro-climate reconstruction for the last 2K based on speleothem records (Khodri et al., in prep) using coherence and singular spectral analyses to depict the temporal evolution of the dominant cyclicities the time series. For the more recent period, we will also use long-term instrumental data of precipitation, river flow and air temperature.

  11. Child Care in the American South: Poverty, Costs, and Quality

    ERIC Educational Resources Information Center

    Collins, Vikki K.

    2012-01-01

    High-quality child care has been shown to improve the academic success and life adjustments of children living in poverty. During the past decade, many American states have adopted voluntary Quality Rating and Improvement (QRI) systems in an attempt to increase the level of quality in child care. Using data compiled by the National Association of…

  12. The Italian-Americans of the South Bend-Mishawaka Area.

    ERIC Educational Resources Information Center

    Fotia, Elizabeth R.; Rasmussen, Karen

    Developed as part of an ethnic heritage studies program, this historical narrative of Italian Americans can enhance cultural awareness. This document presents the story of Italians beginning with cultural roots in Italy and their subsequent emigration to the United States, including to South Bend, Indiana. Four major areas are explored. An account…

  13. Insulating an Ideology: The Enclave Effect on South Florida's Cuban Americans

    ERIC Educational Resources Information Center

    Girard, Chris; Grenier, Guillermo J.

    2008-01-01

    Many Cuban Americans embrace a distinctive anti-Castro ideology. Although this ideology supports the embargo against Cuba--purportedly to bring about the Castro regime's compliance or collapse--the real objectives may be more symbolic than practical. Ultimately, the institutional completeness provided by the enclave in South Florida insulates and…

  14. Genome Sequence of Borrelia chilensis VA1, a South American Member of the Lyme Borreliosis Group

    PubMed Central

    Huang, Weihua; Ojaimi, Caroline; Fallon, John T.; Travisany, Dante; Maass, Alejandro; Ivanova, Larisa; Tomova, Alexandra; González-Acuña, Daniel; Cabello, Felipe C.

    2015-01-01

    Borrelia chilensis strain VA1 is a recently described South American member of the Borrelia burgdorferi sensu lato complex from Chile. Whole-genome sequencing analysis determined its linear chromosome and plasmids lp54 and cp26, confirmed its membership in the Lyme borreliosis group, and will open new research avenues regarding its pathogenic potential. PMID:25676758

  15. Teaching English Vocabulary to Elementary Mexican American Students in South Texas: Some Responsive Modern Instructional Strategies

    ERIC Educational Resources Information Center

    Ekiaka Nzai, Valentin; Reyna, Concepción

    2014-01-01

    Teaching reading and vocabulary to Mexican American children in the United States of America today requires an acknowledgment of historical social injustice that continues to affect many communities in South Texas. This article debriefs some vocabulary teaching strategies--such as mnemonics and game play under the learning centers…

  16. Learning to Teach about Race: The Racialized Experience of a South Asian American Feminist Educator

    ERIC Educational Resources Information Center

    Gnanadass, Edith

    2014-01-01

    This article examines the intellectual and experiential journey of a South Asian American (SAA) feminist who teaches about race and anti-racist praxis in the United States. It starts with her struggles trying to teach about race through the lens of White privilege and ends by sharing her current teaching practices which foreground the concept of…

  17. Writing Policies and Procedures in a U.S./South American Context.

    ERIC Educational Resources Information Center

    Thatcher, Barry L.

    2000-01-01

    Explores two cases of professional communication among United States and South American personnel in one multinational organization in Quito, Ecuador. Suggests that a mere taboo approach to teaching cross-cultural communication will not work. Finds that collaborative writing proved to be a good form of intercultural training for both United States…

  18. Importation of Hybrid Human-Associated Trypanosoma cruzi Strains of Southern South American Origin, Colombia

    PubMed Central

    Ramirez, Juan David; Llewellyn, Martin S.; Guhl, Felipe; Miles, Michael A.

    2016-01-01

    We report the characterization of Trypanosoma cruzi of southern South American origin among humans, domestic vectors, and peridomestic hosts in Colombia using high-resolution nuclear and mitochondrial genotyping. Expanding our understanding of the geographic range of lineage TcVI, which is associated with severe Chagas disease, will help clarify risk of human infection for improved disease control. PMID:27434772

  19. A Part, Yet Apart: South Asians in Asian America. Asian American History and Culture Series.

    ERIC Educational Resources Information Center

    Shankar, Lavina Dhingra, Ed.; Srikanth, Rajini, Ed.

    The essays in this collection consider the extent to which South Asian Americans are included within "Asian America" as the term is applied to academic programs and admissions policies, grassroots community organizing and politics, and critical analyses of cultural products. The essays are: (1) "Within Kaleidoscope Eyes: The Potential (Dangers) of…

  20. Importation of Hybrid Human-Associated Trypanosoma cruzi Strains of Southern South American Origin, Colombia.

    PubMed

    Messenger, Louisa A; Ramirez, Juan David; Llewellyn, Martin S; Guhl, Felipe; Miles, Michael A

    2016-08-01

    We report the characterization of Trypanosoma cruzi of southern South American origin among humans, domestic vectors, and peridomestic hosts in Colombia using high-resolution nuclear and mitochondrial genotyping. Expanding our understanding of the geographic range of lineage TcVI, which is associated with severe Chagas disease, will help clarify risk of human infection for improved disease control. PMID:27434772

  1. Coping with Discrimination: The Subjective Well-Being of South Asian American Women

    ERIC Educational Resources Information Center

    Liang, Christopher T. H.; Nathwani, Anisha; Ahmad, Sarah; Prince, Jessica K.

    2010-01-01

    The relationship between coping strategies used by South Asian American women and subjective well-being (SWB) was studied. Second-generation women were found to use more support compared with 1st-generation women. Problem-solving coping was inversely related to age. Avoidance coping was found to predict SWB when controlling for age and…

  2. A correlated shortening of the North and South American monsoon seasons in the past few decades

    NASA Astrophysics Data System (ADS)

    Arias, Paola A.; Fu, Rong; Vera, Carolina; Rojas, Maisa

    2015-12-01

    Our observational analysis shows that the wet seasons of the American monsoon systems have shortened since 1978 due to correlated earlier retreats of the North American monsoon (NAM) and late onsets of the southern Amazon wet season, an important part of the South American monsoon (SAM). These changes are related to the combination of the global sea surface temperature (SST) warming mode, the El Niño-Southern Oscillation (ENSO), the Atlantic Multidecadal Oscillation (AMO), the westward shift of the North Atlantic subtropical high (NASH), and the enhancement of Pacific South American and Pacific North American wave train patterns, which induces variations of the regional circulation at interannual and decadal scales. The joint contributions from these forcing factors are associated with a stronger and more equatorward regional Hadley cell, which enhances convergence towards the equator, strengthening and possibly delaying the retreat of the tropical part of the NAM. This in turn accelerates the demise of the northern NAM and delays the reversal of the cross-equatorial flow over South America, reducing moisture transport to the SAM and delaying its onset. In addition, the thermodynamic response to warming appears to cause local drier land conditions over both regions, reinforcing the observed changes in these monsoons. Although previous studies have identified the isolated influence of the regional Hadley cell, ENSO, AMO, global SST warming, and NASH on the NAM, the correlated changes between NAM and SAM through variations of the cross-equatorial flow had not been established before.

  3. The Acculturation of Parenting Cognitions: A Comparison of South Korean, Korean Immigrant, and European American Mothers

    PubMed Central

    Cote, Linda R.; Kwak, Keumjoo; Putnick, Diane L.; Chung, Hyun Jin; Bornstein, Marc H.

    2016-01-01

    A three-culture comparison – native South Korean, Korean immigrants to the United States, and native European American mothers – of two types of parenting cognitions – attributions and self-perceptions – was undertaken to explore cultural contributions to parenting cognitions and their adaptability among immigrant mothers. Attributions and self-perceptions of parenting were chosen because they influence parenting behavior and children’s development and vary cross-culturally. One hundred seventy-nine mothers of 20-month-old children participated: 73 South Korean, 50 Korean immigrant, and 56 European American. Korean mothers differed from European American mothers on four of the five types of attributions studied and on all four self-perceptions of parenting, and these differences were largely consistent with the distinct cultural values of South Korea and the United States. Generally, Korean immigrant mothers’ attributions for parenting more closely resembled those of mothers in the United States, whereas their self-perceptions of parenting more closely resembled those of mothers in South Korea. This study provides insight into similarities and differences in cultural models of parenting, and information about the acculturation of parenting cognitions among immigrants from South Korea. PMID:26912926

  4. South American Spider Mites: New Hosts and Localities

    PubMed Central

    Mendonça, Renata S; Navia, Denise; Diniz, Ivone R; Flechtmann, Carlos HW

    2011-01-01

    In order to contribute to taxonomic information on Tetranychid mites (Acari: Tetranychidae) in South America, surveys were conducted in Brazil (15 States and the Federal District) and Uruguay (one Department); 550 samples of 120 plant species were collected. Tetranychid mite infestations were confirmed in 204 samples, and 22 species belonging to seven genera of the Bryobiinae and Tetranychinae subfamilies were identified on 58 different host plants. Thirty-six new plant hosts were found in Brazil, South America, and worldwide for the following species: Eutetranychus banksi (McGregor); Mononychellus tanajoa (Bondar); Oligonychus anonae Paschoal; O. mangiferus (Rahman and Sapra); Tetranychus bastosi Tuttle, Baker and Sales; T. desertorum Banks, 1900, T. evansi Baker and Pritchard; T. ludeni Zacher; T. mexicanus (McGregor); T. neocaledonicus André; and T. urticae Koch. Four new localities in Brazil were reported for Eotetranychus tremae De Leon; O. anonae; Panonychus ulmi (Koch); and T. gloveri Baker and Pritchard. PMID:22224405

  5. Anembryonic Gestation in Wild South American Sea Lion, Otaria flavescens.

    PubMed

    Grandi, M F; Crespo, E A; Dans, S L

    2016-10-01

    We present the first record and description of an anembryonic gestation in a wild South America sea lion, Otaria flavescens (Carnivora, Pinniped). This is the first report of an anembryonic gestation in a wild marine mammal species. This description furthers the knowledge of general aspects of the reproduction of an otariid species, which presents the particularities of delayed implantation and polygynic breeding system, and adds information on a reproductive abnormality in marine mammals. PMID:26497953

  6. Early development of the south Central American margin: mechanisms and tectonic implications

    NASA Astrophysics Data System (ADS)

    Buchs, D. M.; Baumgartner, P. O.; Arculus, R.; Montes, C.; Bayona, G.; Cardona, A.

    2012-04-01

    The south Central American margin forms the SW border of the Caribbean Plate on top of the subducting Cocos and Nazca Plates between Nicaragua and Colombia. New and previous tectonostratigraphic, age and geochemical results show that the forearc basement between south Costa Rica and east Panama is composed of autochthonous and accreted sequences that provide important constraints on the development of the south Central American margin, the evolution of the Caribbean Plate and the formation of an inter-American land bridge. Autochtonous sequences in the forearc include three tectonostratigraphic units that occur at a regional scale: (1) a Late Cretaceous oceanic plateau considered to represent an extension of the Caribbean Large Igneous Province (CLIP) at the base of the arc; (2) Late Campanian to Maastrichtian protoarc sequences that cover or intrude the oceanic plateau; and (3) Maastrichtian to Eocene sequences of a more mature volcanic arc that overlies or intrude preceding units. These units clearly indicate that subduction initiation along the margin and, thus, the birth of the Caribbean Plate occurred in the Campanian. Incipient subduction was possibly triggered or facilitated by contrasted lithospheric strength across the edge of the CLIP and collision between the CLIP and South America during westward migration of South America. Accreted sequences in the forearc include mostly Late Cretaceous to Eocene seamount fragments between south Costa Rica and west Panama, with additional Eocene to Miocene olistostromal and hemipelagic sediments in south Costa Rica. The age and tectonostratigraphic relationships of accreted sequences, autochtonous sequences, and overlying forearc slope sediment suggest that subduction erosion, punctuated by local seamount or sediment accretion was the dominant process controlling the evolution of the outer margin at least until the Miocene. A major tectonic event affected the margin in the Middle Eocene, which is indicated by a

  7. The Ethnic History of South Carolina. American History, South Carolina History. Grade 8.

    ERIC Educational Resources Information Center

    Charleston County School District, North Charleston, SC. Div. of Instruction.

    This guide for eighth grade teachers was the product of a Title IX ethnic studies project. The guide was designed to supplement the regular South Carolina state history textbooks and place in a more positive frame of reference the ethnic contributions that specific ethnic groups have made to South Carolina history. Written by teachers, the guide…

  8. Rapid coastal spread of First Americans: Novel insights from South America's Southern Cone mitochondrial genomes

    PubMed Central

    Bodner, Martin; Perego, Ugo A.; Huber, Gabriela; Fendt, Liane; Röck, Alexander W.; Zimmermann, Bettina; Olivieri, Anna; Gómez-Carballa, Alberto; Lancioni, Hovirag; Angerhofer, Norman; Bobillo, Maria Cecilia; Corach, Daniel; Woodward, Scott R.; Salas, Antonio; Achilli, Alessandro; Torroni, Antonio; Bandelt, Hans-Jürgen; Parson, Walther

    2012-01-01

    It is now widely agreed that the Native American founders originated from a Beringian source population ∼15–18 thousand years ago (kya) and rapidly populated all of the New World, probably mainly following the Pacific coastal route. However, details about the migration into the Americas and the routes pursued on the continent still remain unresolved, despite numerous genetic, archaeological, and linguistic investigations. To examine the pioneering peopling phase of the South American continent, we screened literature and mtDNA databases and identified two novel mitochondrial DNA (mtDNA) clades, here named D1g and D1j, within the pan-American haplogroup D1. They both show overall rare occurrences but local high frequencies, and are essentially restricted to populations from the Southern Cone of South America (Chile and Argentina). We selected and completely sequenced 43 D1g and D1j mtDNA genomes applying highest quality standards. Molecular and phylogeographic analyses revealed extensive variation within each of the two clades and possibly distinct dispersal patterns. Their age estimates agree with the dating of the earliest archaeological sites in South America and indicate that the Paleo-Indian spread along the entire longitude of the American double continent might have taken even <2000 yr. This study confirms that major sampling and sequencing efforts are mandatory for uncovering all of the most basal variation in the Native American mtDNA haplogroups and for clarification of Paleo-Indian migrations, by targeting, if possible, both the general mixed population of national states and autochthonous Native American groups, especially in South America. PMID:22333566

  9. Rapid coastal spread of First Americans: novel insights from South America's Southern Cone mitochondrial genomes.

    PubMed

    Bodner, Martin; Perego, Ugo A; Huber, Gabriela; Fendt, Liane; Röck, Alexander W; Zimmermann, Bettina; Olivieri, Anna; Gómez-Carballa, Alberto; Lancioni, Hovirag; Angerhofer, Norman; Bobillo, Maria Cecilia; Corach, Daniel; Woodward, Scott R; Salas, Antonio; Achilli, Alessandro; Torroni, Antonio; Bandelt, Hans-Jürgen; Parson, Walther

    2012-05-01

    It is now widely agreed that the Native American founders originated from a Beringian source population ~15-18 thousand years ago (kya) and rapidly populated all of the New World, probably mainly following the Pacific coastal route. However, details about the migration into the Americas and the routes pursued on the continent still remain unresolved, despite numerous genetic, archaeological, and linguistic investigations. To examine the pioneering peopling phase of the South American continent, we screened literature and mtDNA databases and identified two novel mitochondrial DNA (mtDNA) clades, here named D1g and D1j, within the pan-American haplogroup D1. They both show overall rare occurrences but local high frequencies, and are essentially restricted to populations from the Southern Cone of South America (Chile and Argentina). We selected and completely sequenced 43 D1g and D1j mtDNA genomes applying highest quality standards. Molecular and phylogeographic analyses revealed extensive variation within each of the two clades and possibly distinct dispersal patterns. Their age estimates agree with the dating of the earliest archaeological sites in South America and indicate that the Paleo-Indian spread along the entire longitude of the American double continent might have taken even <2000 yr. This study confirms that major sampling and sequencing efforts are mandatory for uncovering all of the most basal variation in the Native American mtDNA haplogroups and for clarification of Paleo-Indian migrations, by targeting, if possible, both the general mixed population of national states and autochthonous Native American groups, especially in South America. PMID:22333566

  10. Validation of South American terrestrial gravity anomalies by GOCE

    NASA Astrophysics Data System (ADS)

    Fecher, Thomas; Pail, Roland; Gruber, Thomas; Holmes, Simon

    2015-04-01

    Since its launch in 2009, ESA's GOCE mission has generated high-accuracy gravity field information, of near-global coverage, for the long- to medium-wavelength part of the gravity field (<=degree/order 260). These highly accurate gravity data are especially important for regions such as South America, Africa or Asia, where coverage and/or accuracy of alternate data sets, mostly gravimetry, are relatively poor. In these regions, the GOCE data can be useful in identifying and assessing suspect terrestrial data. Specifically, in coordination with partner organizations, we are already leveraging satellite gravity field missions to identify inconsistencies between different regional gravity anomaly data sets. Many of these inconsistencies relate to data quality issues. Resolving these issues better enables the terrestrial gravity data to strengthen and correct the satellite gravity models at their higher end (degree/order 200 to 260). The harmonization between terrestrial and satellite datasets reduces the commission error in gravity modeling over the associated range. Remaining issues not related to data quality can then be isolated for additional study. For example, a host of geophysical and temporal issues may be contributing to irregularities. In this paper, the quality of a South America data set of gravity anomalies shall be analyzed. The accuracy of the gravity anomalies shall be assessed, and systematic errors shall be detected. For this purpose, consistent gravity field corrections have to be applied. The aim of the revision of the data set is to exclude bad data and to provide accuracies which can serve as a stochastic model in the frame of a combined solution. By this procedure, the performance of a gravity field model based on the combination of satellite and terrestrial observations should be improved for South America.

  11. A satellite magnetic model of northeastern South American aulacogens

    NASA Technical Reports Server (NTRS)

    Longacre, M. B.; Hinze, W. J.; Von Frese, R. R. B.

    1982-01-01

    Magnetic modeling of the Amazon River and Takatu Aulacogens in northeastern South America illustrate the utility of satellite magnetic data in characterizing the properties and structure of the lithosphere. Specifically, reduction of preliminary Magsat scalar magnetic anomaly data to an equivalent condition of vertical polarization shows a general correlation between magnetic anomaly minima and the Amazon River and Takatu Aulacogens. Surface gravity data demonstrate a correlative positive anomaly. Spherical earth modeling of the magnetic data indicates a less magnetic crust associated with the aulacogens which is compatible with previous studies over the Mississippi River Aulacogen and Rio Grande Rift in North America.

  12. Shaking Eden: Voyages, Bodies and Change in the Social Construction of South American Skies

    NASA Astrophysics Data System (ADS)

    López, Alejandro Martín

    2015-05-01

    South America presents a clear example of the importance of displacements and exchanges in shaping human societies. Nevertheless, the academic works, following the ideas of the first European visitors, have tended to see it as an undisturbed Eden in a `state of nature.´ For too long, South American societies were thought of as small units without history, isolated from each other. The opposition to the excesses of diffusionism helped to reinforce that image. However, in recent years this static and `naturaĺ representation has collapsed. New works from the most varied perspectives show us a changing and interconnected South America, where the notions of body, person and territory are complex social constructions and not the expression of an 'unmediated' experience of the world. We discuss the implications of these new perspectives of thinking on South America for the study of ways of perceiving and representing the sky in this region.

  13. Ancient collagen reveals evolutionary history of the endemic South American 'ungulates'.

    PubMed

    Buckley, Michael

    2015-05-01

    Since the late eighteenth century, fossils of bizarre extinct creatures have been described from the Americas, revealing a previously unimagined chapter in the history of mammals. The most bizarre of these are the 'native' South American ungulates thought to represent a group of mammals that evolved in relative isolation on South America, but with an uncertain affinity to any particular placental lineage. Many authors have considered them descended from Laurasian 'condylarths', which also includes the probable ancestors of perissodactyls and artiodactyls, whereas others have placed them either closer to the uniquely South American xenarthrans (anteaters, armadillos and sloths) or the basal afrotherians (e.g. elephants and hyraxes). These hypotheses have been debated owing to conflicting morphological characteristics and the hitherto inability to retrieve molecular information. Of the 'native' South American mammals, only the toxodonts and litopterns persisted until the Late Pleistocene-Early Holocene. Owing to known difficulties in retrieving ancient DNA (aDNA) from specimens from warm climates, this research presents a molecular phylogeny for both Macrauchenia patachonica (Litopterna) and Toxodon platensis (Notoungulata) recovered using proteomics-based (liquid chromatography-tandem mass spectrometry) sequencing analyses of bone collagen. The results place both taxa in a clade that is monophyletic with the perissodactyls, which today are represented by horses, rhinoceroses and tapirs. PMID:25833851

  14. Ancient collagen reveals evolutionary history of the endemic South American ‘ungulates’

    PubMed Central

    Buckley, Michael

    2015-01-01

    Since the late eighteenth century, fossils of bizarre extinct creatures have been described from the Americas, revealing a previously unimagined chapter in the history of mammals. The most bizarre of these are the ‘native’ South American ungulates thought to represent a group of mammals that evolved in relative isolation on South America, but with an uncertain affinity to any particular placental lineage. Many authors have considered them descended from Laurasian ‘condylarths’, which also includes the probable ancestors of perissodactyls and artiodactyls, whereas others have placed them either closer to the uniquely South American xenarthrans (anteaters, armadillos and sloths) or the basal afrotherians (e.g. elephants and hyraxes). These hypotheses have been debated owing to conflicting morphological characteristics and the hitherto inability to retrieve molecular information. Of the ‘native’ South American mammals, only the toxodonts and litopterns persisted until the Late Pleistocene–Early Holocene. Owing to known difficulties in retrieving ancient DNA (aDNA) from specimens from warm climates, this research presents a molecular phylogeny for both Macrauchenia patachonica (Litopterna) and Toxodon platensis (Notoungulata) recovered using proteomics-based (liquid chromatography–tandem mass spectrometry) sequencing analyses of bone collagen. The results place both taxa in a clade that is monophyletic with the perissodactyls, which today are represented by horses, rhinoceroses and tapirs. PMID:25833851

  15. SOUTH AMERICAN COLLABORATION IN SCIENTIFIC PUBLICATIONS ON LEISHMANIASIS: BIBLIOMETRIC ANALYSIS IN SCOPUS (2000-2011)

    PubMed Central

    Huamaní, Charles; Romaní, Franco; González-Alcaide, Gregorio; Mejia, Miluska O.; Ramos, José Manuel; Espinoza, Manuel; Cabezas, César

    2014-01-01

    Objectives: Evaluate the production and the research collaborative network on Leishmaniasis in South America. Methods: A bibliometric research was carried out using SCOPUS database. The analysis unit was original research articles published from 2000 to 2011, that dealt with leishmaniasis and that included at least one South American author. The following items were obtained for each article: journal name, language, year of publication, number of authors, institutions, countries, and others variables. Results: 3,174 articles were published, 2,272 of them were original articles. 1,160 different institutional signatures, 58 different countries and 398 scientific journals were identified. Brazil was the country with more articles (60.7%) and Oswaldo Cruz Foundation (FIOCRUZ) had 18% of Brazilian production, which is the South American nucleus of the major scientific network in Leishmaniasis. Conclusions: South American scientific production on Leishmaniasis published in journals indexed in SCOPUS is focused on Brazilian research activity. It is necessary to strengthen the collaboration networks. The first step is to identify the institutions with higher production, in order to perform collaborative research according to the priorities of each country. PMID:25229217

  16. How does Preceding Soil Moisture Influence the Onset of the South American Monsoon?

    NASA Astrophysics Data System (ADS)

    Berbery, E. H.; Collini, E. A.

    2006-05-01

    The South American Monsoon System achieves maximum precipitation over the southern Amazon basin and the Brazilian highlands during the austral summer. The precipitation pattern associated with the monsoon system extends southeastward to southeastern Brazil and into the Atlantic Ocean as a band of clouds and precipitation called the South Atlantic Convergence Zone. Earlier studies have noted the important role of advective processes, and in particular the effect of the South American Low-level Jet east of the Andes Mountains, in the onset and maintenance of the monsoon precipitation. The local effects of the land surface onto the onset of the South American monsoon are less understood. This study discusses the sensitivity of the monsoon precipitation to changes in initial soil moisture conditions using ensembles of month long simulations with the regional mesoscale Eta model. The sensitivity experiments to soil moisture changes suggest that soil over the subtropical region seems to be close to saturation. Consequently, precipitation is not as sensitive to increases of soil moisture as it is to decreases. When the initial soil moisture is reduced, changes in precipitation respond to two basic mechanisms. On the one hand the reduction of soil moisture implies less availability of water for evaporation; on the other hand, changes in the Bowen ratio also imply a deeper (and drier) boundary layer which results in a more elevated Low-level Jet, with a consequent reduction of the moisture transports into the monsoon region. The two mechanisms act concurrently to reduce the core monsoon precipitation.

  17. Response of South American ecosystems to precipitation variability

    SciTech Connect

    Ganguly, Auroop R; Erickson III, David J; Bras, Rafael L

    2009-12-01

    The Ecosystem Demography Model 2 is a dynamic ecosystem model and land surface energy balance model. ED2 discretizes landscapes of particular terrain and meteorology into fractional areas of unique disturbance history. Each fraction, defined by a shared vertical soil column and canopy air space, contains a stratum of plant groups unique in functional type, size and number density. The result is a vertically distributed representation of energy transfer and plant dynamics (mortality, productivity, recruitment, disturbance, resource competition, etc) that successfully approximates the behaviour of individual-based vegetation models. In previous exercises simulating Amazonian land surface dynamics with ED2, it was observed that when using grid averaged precipitation as an external forcing the resulting water balance typically over-estimated leaf interception and leaf evaporation while under estimating through-fall and transpiration. To investigate this result, two scenario were conducted in which land surface biophysics and ecosystem demography over the Northern portion of South America are simulated over {approx}200 years: (1) ED2 is forced with grid averaged values taken from the ERA40 reanalysis meteorological dataset; (2) ED2 is forced with ERA40 reanalysis, but with its precipitation re-sampled to reflect statistical qualities of point precipitation found at rain gauge stations in the region. The findings in this study suggest that the equilibrium moisture states and vegetation demography are co-dependent and show sensitivity to temporal variability in precipitation. These sensitivities will need to be accounted for in future projections of coupled climate-ecosystem changes in South America.

  18. Response of South American Ecosystems to Precipitation Variability

    NASA Astrophysics Data System (ADS)

    Knox, R. G.; Kim, Y.; Longo, M.; Medvigy, D.; Wang, J.; Moorcroft, P. R.; Bras, R. L.

    2009-12-01

    The Ecosystem Demography Model 2 is a dynamic ecosystem model and land surface energy balance model. ED2 discretizes landscapes of particular terrain and meteorology into fractional areas of unique disturbance history. Each fraction, defined by a shared vertical soil column and canopy air space, contains a stratum of plant groups unique in functional type, size and number density. The result is a vertically distributed representation of energy transfer and plant dynamics (mortality, productivity, recruitment, disturbance, resource competition, etc) that successfully approximates the behaviour of individual-based vegetation models. In previous exercises simulating Amazonian land surface dynamics with ED 2, it was observed that when using grid averaged precipitation as an external forcing the resulting water balance typically over-estimated leaf interception and leaf evaporation while under estimating through-fall and transpiration. To investigate this result, two scenario were conducted in which land surface biophysics and ecosystem demography over the Northern portion of South America are simulated over ~200 years: (1) ED2 is forced with grid averaged values taken from the ERA40 reanalysis meteorological dataset; (2) ED2 is forced with ERA40 reanalysis, but with its precipitation re-sampled to reflect statistical qualities of point precipitation found at rain gauge stations in the region. The findings in this study suggest that the equilibrium moisture states and vegetation demography are co-dependent and show sensitivity to temporal variability in precipitation. These sensitivities will need to be accounted for in future projections of coupled climate-ecosystem changes in South America.

  19. Generational differences in fast food intake among South-Asian Americans: results from a population-based survey.

    PubMed

    Becerra, Monideepa B; Herring, Patti; Marshak, Helen Hopp; Banta, Jim E

    2014-01-01

    The goal of this study was to evaluate the association between generational status and fast food consumption among South-Asian Americans. We conducted a secondary analysis of data from the California Health Interview Survey for 2007, 2009, and 2011. After adjusting for control variables, South-Asian Americans of the third generation or more had a fast food intake rate per week 2.22 times greater than first generation South-Asian Americans. Public health practitioners must focus on ways to improve dietary outcomes among this fast-growing ethnic population in the United States. PMID:25474383

  20. Generational Differences in Fast Food Intake Among South-Asian Americans: Results From a Population-Based Survey

    PubMed Central

    Herring, Patti; Marshak, Helen Hopp; Banta, Jim E.

    2014-01-01

    The goal of this study was to evaluate the association between generational status and fast food consumption among South-Asian Americans. We conducted a secondary analysis of data from the California Health Interview Survey for 2007, 2009, and 2011. After adjusting for control variables, South-Asian Americans of the third generation or more had a fast food intake rate per week 2.22 times greater than first generation South-Asian Americans. Public health practitioners must focus on ways to improve dietary outcomes among this fast-growing ethnic population in the United States. PMID:25474383

  1. South American rainfall impacts associated with inter-El Niño variations

    NASA Astrophysics Data System (ADS)

    Hill, K. J.; Taschetto, A. S.; England, M. H.

    2009-10-01

    The impacts of inter-El Niño events on South American circulation during austral summer are investigated using observations and an atmospheric general circulation model (AGCM). The AGCM was forced with sea surface temperature (SST) anomalies in the tropical Pacific for the two El Niño events of 1997/1998 (EN97) and 2002/2003 (EN02). The strong eastern Pacific SST anomaly of EN97 resulted in a typical displacement of the Walker circulation, causing a decrease in precipitation across the north of South America. A strengthened low-level jet (LLJ) east of the Andes during EN97 enhanced the moisture transport from low latitudes to the subtropics, leading to intensified precipitation over southeastern South America. The simulated circulation in EN02 reveals a weakened LLJ and anomalous convergence of moisture over eastern South America, which can be attributed to a displacement of the Pacific-South American (PSA) mode in response to the different location of the heat sources along the tropical Pacific Ocean.

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

    NASA Astrophysics Data System (ADS)

    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.

  3. Typification of names of South American taxa related to Woodsia montevidensis (Woodsiaceae)

    PubMed Central

    Arana, Marcelo D.; Mynssen, Claudine M.; Zimmer, Brigitte; Ponce, M. Monica

    2016-01-01

    Abstract A revision of the nomenclature of six South American taxa related to Woodsia is presented, as a part of a taxonomic revision of the genus in South America. Lectotypes are selected for Cheilanthes crenata, Woodsia crenata var. pallidipes, Woodsia incisa, Woodsia montevidensis var. fuscipes and the second step lectotypification for Dicksonia montevidensis and Woodsia peruviana, based on the analysis of their protologues and original herbarium material. All names are currently synonyms of Woodsia montevidensis. Physematium incisum (Gillies ex Hook. & Grev.) Kunze constitutes an illegitimate name and Physematium cumingianum is considered as nomen inquirendum. PMID:27489474

  4. Two-Winged Cloeodes in Brazil: New Species, Stage Description, and Key to South American Species

    PubMed Central

    Massariol, Fabiana Criste; Lima, Lucas Ramos Costa; Pinheiro, Ulisses Dos Santos; Quieroz, Luciano Lopes; Oliveira, Leandro Gonçalves; Salles, Frederico Falcão

    2013-01-01

    The present work, based on material from northern, central-western, and northeastern Brazil, contributes to the knowledge of the two-winged Cloeodes Traver (Ephemeroptera: Baetidae) in South America. Two new species, C. maracatu, sp. nov. and C. spaceki, sp. nov., are described, the former based on nymphs and reared adults and the latter only on nymphs; the male and female imago of C. auwe and the female imago of C. redactus are described. Based on these findings, an updated key for South American nymphs and male adults of the two-winged Cloeodes is provided. PMID:23906240

  5. Typification of names of South American taxa related to Woodsia montevidensis (Woodsiaceae).

    PubMed

    Arana, Marcelo D; Mynssen, Claudine M; Zimmer, Brigitte; Ponce, M Monica

    2016-01-01

    A revision of the nomenclature of six South American taxa related to Woodsia is presented, as a part of a taxonomic revision of the genus in South America. Lectotypes are selected for Cheilanthes crenata, Woodsia crenata var. pallidipes, Woodsia incisa, Woodsia montevidensis var. fuscipes and the second step lectotypification for Dicksonia montevidensis and Woodsia peruviana, based on the analysis of their protologues and original herbarium material. All names are currently synonyms of Woodsia montevidensis. Physematium incisum (Gillies ex Hook. & Grev.) Kunze constitutes an illegitimate name and Physematium cumingianum is considered as nomen inquirendum. PMID:27489474

  6. Were the African and South American cratons part of Rodinia?

    NASA Astrophysics Data System (ADS)

    Kröner, A.; Cordani, U. G.; D'Agrella-Filho, M. S.; Brito-Neves, B. B.

    2003-04-01

    The current geochronological and palaeomagnetic database casts doubt on the proposal that the cratons and late Mesoproterozoic and early Neoproterozoic rocks of Africa and South America have played any role in the formation and dispersal of the supercontinent Rodinia, believed to have existed between ˜1000 and 750 Ma ago. First, there is little evidence for the production of large volumes of ˜1.4-1.0 Ga (Kibaran- or Grenvillian-age) continental crust in the Mozambique belt (MB) of East Africa and Madagascar, except, perhaps, in parts of northern Mozambique. This is also valid for most terrains related to West Gondwana, which are made up of basement rocks older than Mesoproterozoic, reworked in the Brasiliano/Pan-African orogenic cycle. This crust cannot be conclusively related to either magmatic accretion processes on the active margin of Rodinia or continental collision leading to amalgamation of the supercontinent. Second, there is no conclusive evidence for a ˜1.0 Ga high-grade metamorphic event in the MB, and the same goes for the Neoproterozoic tectonic belts of South America and West Africa. Third, there is also no evidence for post-1000 Ma sedimentary sequences that were deposited on the passive margin(s) of Rodinia. In contrast, the MB is characterized by extensive structural reworking and metamorphic overprinting of Archaean and Palaeoproterozoic rocks, and these either constitute marginal parts of cratonic domains or represent crustal blocks (terranes or microcontinents?) of unknown derivation. This is also the case for most terrains included in the Borborema/Trans-Saharan belt of northeastern Brazil and West-Central Africa, as well as those of the Central Goiás Massif in central Brazil and the Mantiqueira Province of eastern and southeastern Brazil. There is evidence for extensive granitoid magmatism in the time period ˜950 to <600 Ma whose predominant calc-alkaline chemistry suggests subduction-related active margin processes during the assembly of

  7. Measurements of Light Absorbing Particles on Tropical South American Glaciers

    NASA Astrophysics Data System (ADS)

    Schmitt, C. G.; All, J.; Schwarz, J. P.; Arnott, W. P.; Warthon, J.; Andrade, M.; Celestian, A. J.; Hoffmann, D.; Cole, R. J.; Lapham, E.; Horodyskyj, U. N.; Froyd, K. D.; Liao, J.

    2014-12-01

    Glaciers in the tropical Andes have been losing mass rapidly in recent decades. In addition to the documented increase in temperature, increases in light absorbing particulates deposited on glaciers could be contributing to the observed glacier loss. Here we present results of measurements of light absorbing particles from glaciers in Peru and Bolivia. Samples have been collected by American Climber Science Program volunteers and scientists at altitudes up to 6770 meters. Collected snow samples were melted and filtered in the field. A new inexpensive technique, the Light Absorption Heating Method (LAHM) has been developed for analysis of light absorbing particles collected on filters. Results from LAHM analysis are calibrated using filters with known amounts of fullerene soot, a common industrial surrogate for black carbon (BC). For snow samples collected at the same field location LAHM analysis and measurements from the Single Particle Soot Photometer (SP2) instrument are well correlated (r2 = 0.92). Co-located SP2 and LAHM filter analysis suggest that BC could be the dominant absorbing component of the light absorbing particles in some areas.

  8. Cooperative breeding in South American hunter–gatherers

    PubMed Central

    Hill, Kim; Hurtado, A. Magdalena

    2009-01-01

    Evolutionary researchers have recently suggested that pre-modern human societies habitually practised cooperative breeding and that this feature helps explain human prosocial tendencies. Despite circumstantial evidence that post-reproductive females and extra-pair males both provide resources required for successful reproduction by mated pairs, no study has yet provided details about the flow of food resources by different age and sex categories to breeders and offspring, nor documented the ratio of helpers to breeders. Here, we show in two hunter–gatherer societies of South America that each breeding pair with dependent offspring on average obtained help from approximately 1.3 non-reproductive adults. Young married males and unmarried males of all ages were the main food providers, accounting for 93–100% of all excess food production available to breeding pairs and their offspring. Thus, each breeding pair with dependants was provisioned on average by 0.8 adult male helpers. The data provide no support for the hypothesis that post-reproductive females are the main provisioners of younger reproductive-aged kin in hunter–gatherer societies. Demographic and food acquisition data show that most breeding pairs can expect food deficits owing to foraging luck, health disabilities and accumulating dependency ratio of offspring in middle age, and that extra-pair provisioning may be essential to the evolved human life history. PMID:19692401

  9. An overview of musical instruments used in South American dance traditions

    NASA Astrophysics Data System (ADS)

    Wheeler, Paul A.

    2002-11-01

    Musical instruments used in South American dances combine elements from Amerindian, African, and European musical traditions. The Amerindian influence can be seen in Andean instruments, such as the end-blown flute, panpipe, and charango (modified from the European guitar). The berimau, a musical bow used in the Brazilian capoeira dance, is an example of African influence. The bandoneon is a square-ended German concertina most famous for its use in the tango from Argentina. This paper provides an overview of the musical instruments commonly used in South American dance traditions in relationship to their origins. The acoustics of some of these instruments, such as the guitar, has been studied in detail, whereas others, like the Brazilian cuica, provide opportunity for new studies.

  10. Extending Public Health: The Rockefeller Sanitary Commission and Hookworm in the American South

    PubMed Central

    McGuire, Robert A.; Wittman, Barbara

    2014-01-01

    The Rockefeller Sanitary Commission for the Eradication of Hookworm Disease (1909–1914) fielded a philanthropic public health project that had three goals: to estimate hookworm prevalence in the American South, provide treatment, and eradicate the disease. Activities covered 11 Southern states, and Rockefeller teams found that about 40% of the population surveyed was infected. However, the commission met strong resistance and lacked the time and resources to achieve universal county coverage and meet project goals. We explore how these constraints triggered project changes that systematically reshaped project operations and the characteristics of the counties surveyed and treated. We show that county selectivity reduced the project’s initial potential to affect hookworm prevalence estimates, treatment, and eradication in the American South. PMID:24228676

  11. Molecular Phylogeny of the Myxobolus and Henneguya Genera with Several New South American Species

    PubMed Central

    Carriero, Mateus Maldonado; Adriano, Edson A.; Silva, Márcia R. M.; Ceccarelli, Paulo S.; Maia, Antonio A. M.

    2013-01-01

    The present study consists of a detailed phylogenetic analysis of myxosporeans of the Myxobolus and Henneguya genera, including sequences from 12 Myxobolus/Henneguya species, parasites of South American pimelodids, bryconids and characids. Maximum likelihood and maximum parsimony analyses, based on 18 S rDNA gene sequences, showed that the strongest evolutionary signal is the phylogenetic affinity of the fish hosts, with clustering mainly occurring according to the order and/or family of the host. Of the 12 South American species studied here, six are newly described infecting fish from the Brazilian Pantanal wetland. Henneguya maculosus n. sp. and Myxobolus flavus n. sp. were found infecting both Pseudoplatystoma corruscans and Pseudoplatystoma reticulatum; Myxobolus aureus n. sp. and Myxobolus pantanalis n. sp. were observed parasitizing Salminus brasiliensis and Myxobolus umidus n. sp. and Myxobolus piraputangae n. sp. were detected infecting Brycon hilarii. PMID:24040037

  12. Splendid oddness: revisiting the curious trophic relationships of South American Pleistocene mammals and their abundance.

    PubMed

    Fariña, Richard A; Czerwonogora, Ada; di Giacomo, Mariana

    2014-03-01

    The South American Pleistocene mammal fauna includes great-sized animals that have intrigued scientists for over two centuries. Here we intend to update the knowledge on its palaeoecology and provide new evidence regarding two approaches: energetics and population density and relative abundance of fossils per taxa. To determine whether an imbalance exists, population density models were applied to several South American fossil faunas and the results compared to those that best describe the palaeoecology of African faunas. The results on the abundance study for Uruguay and the province of Buenos Aires during the Lujanian stage/age reveal that bulk-feeding ground sloths (Lestodon and Glossotherium) were more represented in the first territory, while the more selective Scelidotherium and Megatherium were more abundant in the second. Although the obtained values were corrected to avoid size-related taphonomic biases, linear regressions of abundance vs. body mass plots did not fit the expected either for first or second consumers. South American Pleistocene faunas behave differently from what models suggest they should. Changes in sea level and available area could account for these differences; the possibility of a floodplain in the area then emerged could explain seasonal changes, which would modify the calculations of energetics and abundance. PMID:24676170

  13. No evidence for an afrotherian-like delayed dental eruption in South American notoungulates.

    PubMed

    Billet, Guillaume; Martin, Thomas

    2011-06-01

    The fossil South American ungulates are of great interest relative to the new phylogenetic framework elaborated for living placental mammals. In particular, studies on these endemic taxa can allow for testing congruence between southern placental phylogeny and plate tectonics, beyond what has already been suggested in the Atlantogenata hypothesis based on extant afrotherians and xenarthrans. The presence of delayed dental eruption relative to skull growth is one feature characterizing the extant afrotherians and possibly the xenarthrans. Late dental eruption has been mentioned previously in South American notoungulates, thus suggesting possible resemblance with afrotherians and perhaps xenarthrans. We provide here a detailed study of the dental eruption pattern relative to the skull growth in the notoungulates. In contrast to previous statements, our results demonstrate that there is currently no evidence for an afrotherian-like delayed dental eruption in this group. For now, the inferred absence of a delayed dental eruption in notoungulates does not support atlantogenatan/afrotherian affinities for the Notoungulata, but other atlantogenatan/afrotherian characteristics remain to be explored in more detail in this group and other South American ungulates. PMID:21494870

  14. Nuclear ribosomal DNA evidence for a western North American origin of Hawaiian and South American species of Sanicula (Apiaceae)

    PubMed Central

    Vargas, Pablo; Baldwin, Bruce G.; Constance, Lincoln

    1998-01-01

    Results from phylogenetic analysis of nuclear rDNA internal transcribed spacer (ITS) sequences from a worldwide sample of Sanicula indicate that Hawaiian sanicles (Sanicula sect. Sandwicenses) constitute a monophyletic group that descended from a western North American ancestor in Sanicula sect. Sanicoria, a paraphyletic assemblage of mostly Californian species. A monophyletic group comprising representatives of all 15 species of S. sect. Sanicoria and the three sampled species of S. sect. Sandwicenses was resolved in all maximally parsimonious trees, rooted with sequences from species of Astrantia and Eryngium. All sequences sampled from eastern North American, European, and Asian species of Sanicula fell outside the ITS clade comprising S. sect. Sanicoria and S. sect. Sandwicenses. A lineage comprising the Hawaiian taxa and three species endemic to coastal or near-coastal habitats in western North America (Sanicula arctopoides, Sanicula arguta, and Sanicula laciniata) is diagnosed by nucleotide substitutions and a 24-bp deletion in ITS2. The hooked fruits in Sanicula lead us to conclude that the ancestor of Hawaiian sanicles arrived from North America by external bird dispersal; similar transport has been hypothesized for the North American tarweed ancestor of the Hawaiian silversword alliance (Asteraceae). Two additional long-distance dispersal events involving members of S. sect. Sanicoria can be concluded from the ITS phylogeny: dispersal of Sanicula crassicaulis and Sanicula graveolens from western North America to southern South America. PMID:9419359

  15. Land use change exacerbates tropical South American drought by sea surface temperature variability

    NASA Astrophysics Data System (ADS)

    Lee, Jung-Eun; Lintner, Benjamin R.; Boyce, C. Kevin; Lawrence, Peter J.

    2011-10-01

    Observations of tropical South American precipitation over the last three decades indicate an increasing rainfall trend to the north and a decreasing trend to the south. Given that tropical South America has experienced significant land use change over the same period, it is of interest to assess the extent to which changing land use may have contributed to the precipitation trends. Simulations of the National Center for Atmospheric Research Community Atmosphere Model (NCAR CAM3) analyzed here suggest a non-negligible impact of land use on this precipitation behavior. While forcing the model by imposed historical sea surface temperatures (SSTs) alone produces a plausible north-south precipitation dipole over South America, NCAR CAM substantially underestimates the magnitude of the observed southern decrease in rainfall unless forcing associated with human-induced land use change is included. The impact of land use change on simulated precipitation occurs primarily during the local dry season and in regions of relatively low annual-mean rainfall, as the incidence of very low monthly-mean accumulations (<10 mm/month) increases significantly when land use change is imposed. Land use change also contributes to the simulated temperature increase by shifting the surface turbulent flux partitioning to favor sensible over latent heating. Moving forward, continuing pressure from deforestation in tropical South America will likely increase the occurrence of significant drought beyond what would be expected by anthropogenic warming alone and in turn compound biodiversity decline from habitat loss and fragmentation.

  16. Analysis of the genetic ancestry of patients with oral clefts from South American admixed populations.

    PubMed

    Vieira-Machado, Camilla D; de Carvalho, Flavia M; Santana da Silva, Luiz C; Dos Santos, Sidney E; Martins, Claudia; Poletta, Fernando A; Mereb, Juan C; Vieira, Alexandre R; Castilla, Eduardo E; Orioli, Iêda M

    2016-08-01

    Increased susceptibility to cleft lip, with or without cleft palate (CL±P) has been observed in South America, as related to Amerindian ancestry, using epidemiological data, uniparental markers, and blood groups. In this study, it was evaluated whether this increased risk remains when Amerindian ancestry is estimated using autosomal markers and considered in the predictive model. Ancestry was estimated through genotyping 62 insertion and deletion (INDEL) markers in sample sets of patients with CL±P, patients with cleft palate (CP), and controls, from Patagonia in southern Argentina and Belém in northern Brazil. The Amerindian ancestry in patients from Patagonia with CL±P was greater than in controls although it did not reach statistical significance. The European ancestry in patients with CL±P from Belém and in patients with CP from Belém and Patagonia was higher than in controls and statistically significant for patients with CP who were from Belém. This high contribution of European genetic ancestry among patients with CP who were from Belém has not been previously observed in American populations. Our results do not corroborate the currently accepted risks for CL±P and CP estimated by epidemiological studies in the North American populations and probably reflect the higher admixture found in South American ethnic groups when compared with the same ethnic groups from the North American populations. PMID:27105611

  17. Satellite Elevation Magnetic and Gravity Models of Major South American Plate Tectonic Features

    NASA Technical Reports Server (NTRS)

    Vonfrese, R. R. B.; Hinze, W. J.; Braile, L. W.; Lidiak, E. G.; Keller, G. R. (Principal Investigator); Longacre, M. B.

    1984-01-01

    Some MAGSAT scalar and vector magnetic anomaly data together with regional gravity anomaly data are being used to investigate the regional tectonic features of the South American Plate. An initial step in this analysis is three dimensional modeling of magnetic and gravity anomalies of major structures such as the Andean subduction zone and the Amazon River Aulacogen at satellite elevations over an appropriate range of physical properties using Gaus-Legendre quadrature integration method. In addition, one degree average free-air gravity anomalies of South America and adjacent marine areas are projected to satellite elevations assuming a spherical Earth and available MAGSAT data are processed to obtain compatible data sets for correlation. Correlation of these data sets is enhanced by reduction of the MAGSAT data to radial polarization because of the profound effect of the variation of the magnetic inclination over South America.

  18. Aerosol particle properties in a South American megacity

    NASA Astrophysics Data System (ADS)

    Ulke, Ana; Torres-Brizuela, Marcela; Raga, Graciela; Baumgardner, Darrel; Cancelada, Marcela

    2015-04-01

    The subtropical city of Buenos Aires is located on the western shore of Río de la Plata, on the southeastern coast of Argentina. It is the second largest metropolitan area in South America, with a population density of around 14 thousand people per km2. When all 24 counties of the Great Buenos Aires Metropolitan Area are included it is the third-largest conurbation in Latin America, with a population of around fifteen million inhabitants. The generalized worldwide trend to concentrate human activities in urban regions that continue to expand in area, threatens the local and regional environment. Air pollution in the Buenos Aires airshed is due to local sources (mainly the mobile sources, followed by the electric power plants and some industries) and to distant sources (like biomass burning, dust, marine aerosols and occasionally volcanic ash) whose products arrive in the city area due to the regional transport patterns. Previous research suggests that ambient aerosol particle concentrations should be considered an air quality problem. A field campaign was conducted in Buenos Aires in 2011 in order to characterize some aerosol particles properties measured for the first time in the city. Measurements began in mid- April and continued until December. The field observations were done in a collaborative effort between the Universities of Mexico (UNAM) and Buenos Aires (UBA). A suite of instruments was installed on the roof of an UBA laboratory and classroom buildings (34.54° S, 58.44° W) at an altitude of approximately 30 m above sea level. The measurements included the number concentration of condensation nuclei (CN) larger than approximately 50 nm, the mass concentration of particle-bound polycyclic aromatic hydrocarbons (PPAH), the scattering (Bscat) and absorption (Babs) coefficients at 550 nm and the vertical profiles of backscattered light from aerosols at a wavelength of 910 nm using a ceilometer. In addition, a weather station recorded the meteorological

  19. Meso-American Languages in the Wiregrass: An Investigation of Language Maintenance in North Florida/South Georgia

    ERIC Educational Resources Information Center

    Gladwin, Ransom

    2010-01-01

    This study used oral survey methods to examine first the diversity of Meso-American languages and second the potential language maintenance or loss of these languages among Meso-American language speakers in Wiregrass country (North Florida-South Georgia). Language shift, the process of gradually changing from one first language to another first…

  20. The Cultural Impact on Depression Expression and Attitudes Toward Seeking Professional Help: A Comparative Study of Americans and South Koreans.

    ERIC Educational Resources Information Center

    Yoo, Sung-Kyung

    2001-01-01

    Studies impact of certain cultural variables on South Korean and American college student attitudes toward seeking professional help for symptoms of depression. Finds American students have more positive attitudes toward seeking help due largely to low ratings on vertical and collective individualism scales. Discusses implications for counseling…

  1. Abrupt Late Pleistocene Changes in Northern South American River Run-Off

    NASA Astrophysics Data System (ADS)

    Hoffmann, J.; Bahr, A.; Voigt, S.; Schönfeld, J.; Nuernberg, D.

    2014-12-01

    Paleoenvironmental studies as well as climate models demonstrate that fluvial run-off and moisture availability in the hinterland of the Caribbean react highly sensitively to climatic variations. Deglacial (Late Pleistocene) records document pronounced dry and wet spells over tropical South America which are mainly caused by shifts of the Intertropical Convergence Zone (ITCZ) coupled with South American monsoonal activity. Here we present a high-resolution foraminiferal Ba/Ca and δ18Oseawater record from a core located within the Orinoco outflow area, that give insights into abrupt changes of the hydrology of the Orinoco catchment area and, furthermore, enables us to reconstruct circulation patterns within the Caribbean during deglacial times. Our data, obtained from the surface-dwelling foraminifera Globigerinoides ruber (pink variety), show a distinct increase in Ba/Ca ratios during the Heinrich 1 (H1) interval, as well as during the Dansgaard-Oeschger cycles up to 36 kyr. Based on the multi-proxy evidence we largely attribute the Ba/Ca increase during H1 to enhanced Amazon river run-off, while Orinoco river discharge appears not to be significantly elevated. During Dansgaard-Oeschger cycles, the causal mechanism for enhanced Ba/Ca ratios is an insolation-driven shift of the ITCZ and/or enhanced South American summer monsoon activity. Interestingly, the H1 Ba/Ca shows strong similarities in shape and timing to published Ba/Ca data from Florida Straits.This leads us to the assumption that the South American run-off signal is transported directly into the Atlantic Ocean via Yukatan Strait and Florida Strait and therefore alter the salinity budget in the North Atlantic. The results point to immediate high to low latitude feedbacks which might help to re-inforce the weakening of the overturning circulation during Heinrich Events and Dansgaard-Oeschger cycles.

  2. Comparative analysis of post-breakup basin evolution along the South-American and South-African margins, southern Atlantic

    NASA Astrophysics Data System (ADS)

    Strozyk, F.; Back, S.; Kukla, P. A.

    2012-04-01

    Recently, considerable attempts have been made to compare the sedimentary basin evolution and the associated tectonic framework on both sides of the South-Atlantic. However, yet there are still unresolved questions concerning the tectono-sedimentary styles of margin basin evolution that markedly differ from north to south. Amongst the most striking observations is that multiple phases of uplift and subsidence are recorded after the break-up of the southern South Atlantic margin segment on both sides of the Florianopolis-Walvis Ridge volcanic complex, features that are regarded as atypical when compared to published examples of other post-breakup margin successions. Adding to the heterogeneity of the system, the northernmost segment of the South Atlantic rift and salt basins is also characterized by a pronounced asymmetry, with the Brazilian margin now comprising narrower and deeper rift basins with less salt than the Congo-Gabon conjugate margin. This project deals with a large-scale comparison of this very different post-breakup tectono-stratigraphic development of the southern and northern South American and African continental margins that both record thick post-rift sedimentary successions. To gain detail of the basin margin evolution, we focus on a regional comparison between the post-breakup records archived in the large offshore southern Brazil basins (Pelotas, Santos, Campos) and the post-breakup continental margin successions of offshore Namibia (e.g. Orange Basin) and southern Angola (e.g. Kwanza Basin). A tectonic-stratigraphic comparison of representative geological transects provides a comprehensive basin-to-basin documentation of key factors influencing margin development which include the subsidence development through time, the sediment (in-)flux and storage patterns and the respective type of basin fill (e.g. salt vs. non-salt systems; carbonate-rich vs. clastics-dominated systems). Data from the salt-prone areas offshore South America and southern

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

    NASA Technical Reports Server (NTRS)

    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.

  4. Coastal dunefields of south Brazil as a record of climatic changes in the South American Monsoon System

    NASA Astrophysics Data System (ADS)

    Mendes, Vinícius Ribau; Giannini, Paulo César Fonseca

    2015-10-01

    Southern Brazil coastal dunefields are undergoing a stabilization process that appears to be influenced by climate change. Although this process is relatively well known in the literature, the precise climatic mechanisms involved were not fully understood until now. Here, we propose a new method for integrating meteorological data with dunefield morphology analyses by remote sensing to better understand the impacts of recent climate change on dunefield dynamics. Based on this approach, three successive morphological phases were identified for the Santa Catarina central coast dunefields since 1938: (i) increased sand saturation; (ii) reduced sand saturation with consequent accelerated dune migration; and (iii) decelerated dune migration with trends of stabilization by the vegetation cover. For the coastal dunefields of southern Brazil, the stabilization process can be explained mechanistically by an increase in precipitation and decrease of wind power, both of which were correlated with the intensification of the South American Monsoon System.

  5. Seismic Study of the Southernmost Andes. The Contact Between Scotia and South American Plates

    NASA Astrophysics Data System (ADS)

    Tassone, A.; Cominguez, A. H.; Yagupsky, D.; Alvarado, P.; Lodolo, E.; Menichetti, M.

    2003-12-01

    The relationships between the sinistral Magallanes-Fagnano continental transform fault (MFS), a major segment of the boundary between Scotia-South American plates, and the northern flank of the western Scotia Sea, characterized mostly by compressional structures, have not been yet clearly identified. From data processing, depth seismic-migration modeling and interpretation of 800 km of seismic reflection profiles, this study presents one morpho-structural analysis of these two main tectonic elements. In the offshore part of the Malvinas fold-and-thrust belt, five main seismic units have been recognized. Steeply dipping (mainly to the south) reverse faults cut through the folds. Some of these faults represent old extensional faults of the Middle-Mesozoic Rocas Verdes marginal basin rifting, which have been subsequently inverted by compressional stress fields. A noticeable fault system is recognized in the seismic profile, which involves both the sedimentary cover and the acoustic basement. This fault is interpreted as the result of shear stresses produced along the transcurrent South American-Scotia plate boundary. In the SW border of Malvinas Basin, four major discontinuities were recognized. Each discontinuity represents important changes in the regional geodynamic evolution: Early-Late Jurassic rift; Thermal subsidence (Late Jurassic-Late Cretaceous); Transitional stage, to Foreland basin (Late Cretaceous-Eocene) and Foreland (since Eocene).

  6. Climate Change and American Bullfrog Invasion: What Could We Expect in South America?

    PubMed Central

    Nori, Javier; Urbina-Cardona, J. Nicolás; Loyola, Rafael D.; Lescano, Julián N.; Leynaud, Gerardo C.

    2011-01-01

    Background Biological invasion and climate change pose challenges to biodiversity conservation in the 21st 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. PMID:21991339

  7. South American mammal zoogeography: evidence from convergent evolution in desert rodents.

    PubMed

    Mares, M A

    1975-05-01

    Current theories regarding colonization of South America by mammals are divided between those supported by fossil evidence, which suggest the original mammal fauna of the isolated continent was augmented by early immigrants (primates, caviomorph rodents, and later, procyonids) with a final large influx of northern mammals occurring with the formation of the Panama land bridge, and an opposing view which states that the purported "recent invaders" are too taxonomically and ecologically differentiated to have colonized since the land bridge arose. The second theory suggests that most extant mammals entered before the Plio-Pleistocene land connection. An analysis of degree of physiological adaptation, natural history, distribution patterns, and a multivariate assessment of convergent evolution of Monte Desert rodents indicate that South American cricetine rodents are not highly specialized for desert life. Their degree of adaptation could be accounted for, in large part, by adaptations for arid or semiarid Andean habitats. No Monte Desert rodent has developed the specialized desert traits that have evolved in most desert rodent faunas of the world, although extinct marsupials similar to living bipedal desert rodents were present in the Monte as recently as late Pliocene. Evidence suggests that Monte caviomorphs have been associated with the desert for a longer period than cricetines, and that the latter represent a fairly recent invasion of the Monte Desert. The data thus support the first hypothesis of South American mammal colonization. PMID:1057165

  8. South American Summer Monsoon of 1997/1998 and 1998/1999

    NASA Technical Reports Server (NTRS)

    Lau, William K.-M.; Zhou, Jiayu

    2000-01-01

    It is well known that during El Nino years severe drought occurs in the area of Amazon and northeastern Brazil. According to the linear model result the reduced latent heating over the Amazon may lead to a weaker than normal upper tropospheric Bolivian high. As a result, some studies have suggested a weaker South American summer monsoon (SASM) during El Nino years. Using re-analysis. Zhou and Lau data found a statistically significant positive correlation between the tropical eastern Pacific sea surface temperature (SST) and the strength of low-level jet (LLJ) along the eastern foothills of the tropical-subtropical Andes. Douglas also showed a strong LLJ at Santa Cruz, Bolivia during a special pilot balloon observation period in 1997/98 El Nino austral summer. Since this LLJ is an integral part of the monsoon system in the summertime, these results indicated that SASM could be stronger than normal in El Nino years. To clarify this issue, we conducted an investigation on SASM anomaly in the recent ENSO event of 1997/98 El Nino and 1998/99 La Nina In the following we first give a brief review on SASM and the interannual variability of summer rainfall over South America. Then, the impact of 1997-99 ENSO on the South American regional thermal structure and its dynamical consequences to SASM will be discussed.

  9. Mitochondrial control region haplotypes of the South American sea lion Otaria flavescens (Shaw, 1800).

    PubMed

    Artico, L O; Bianchini, A; Grubel, K S; Monteiro, D S; Estima, S C; Oliveira, L R de; Bonatto, S L; Marins, L F

    2010-09-01

    The South American sea lion, Otaria flavescens, is widely distributed along the Pacific and Atlantic coasts of South America. However, along the Brazilian coast, there are only two nonbreeding sites for the species (Refúgio de Vida Silvestre da Ilha dos Lobos and Refúgio de Vida Silvestre do Molhe Leste da Barra do Rio Grande), both in Southern Brazil. In this region, the species is continuously under the effect of anthropic activities, mainly those related to environmental contamination with organic and inorganic chemicals and fishery interactions. This paper reports, for the first time, the genetic diversity of O. flavescens found along the Southern Brazilian coast. A 287-bp fragment of the mitochondrial DNA control region (D-loop) was analyzed. Seven novel haplotypes were found in 56 individuals (OFA1-OFA7), with OFA1 being the most frequent (47.54%). Nucleotide diversity was moderate (π = 0.62%) and haplotype diversity was relatively low (67%). Furthermore, the median joining network analysis indicated that Brazilian haplotypes formed a reciprocal monophyletic clade when compared to the haplotypes from the Peruvian population on the Pacific coast. These two populations do not share haplotypes and may have become isolated some time back. Further genetic studies covering the entire species distribution are necessary to better understand the biological implications of the results reported here for the management and conservation of South American sea lions. PMID:20838754

  10. A bayesian approach to genome/linguistic relationships in native South Americans.

    PubMed

    Amorim, Carlos Eduardo Guerra; Bisso-Machado, Rafael; Ramallo, Virginia; Bortolini, Maria Cátira; Bonatto, Sandro Luis; Salzano, Francisco Mauro; Hünemeier, Tábita

    2013-01-01

    The relationship between the evolution of genes and languages has been studied for over three decades. These studies rely on the assumption that languages, as many other cultural traits, evolve in a gene-like manner, accumulating heritable diversity through time and being subjected to evolutionary mechanisms of change. In the present work we used genetic data to evaluate South American linguistic classifications. We compared discordant models of language classifications to the current Native American genome-wide variation using realistic demographic models analyzed under an Approximate Bayesian Computation (ABC) framework. Data on 381 STRs spread along the autosomes were gathered from the literature for populations representing the five main South Amerindian linguistic groups: Andean, Arawakan, Chibchan-Paezan, Macro-Jê, and Tupí. The results indicated a higher posterior probability for the classification proposed by J.H. Greenberg in 1987, although L. Campbell's 1997 classification cannot be ruled out. Based on Greenberg's classification, it was possible to date the time of Tupí-Arawakan divergence (2.8 kya), and the time of emergence of the structure between present day major language groups in South America (3.1 kya). PMID:23696865

  11. A Bayesian Approach to Genome/Linguistic Relationships in Native South Americans

    PubMed Central

    Amorim, Carlos Eduardo Guerra; Bisso-Machado, Rafael; Ramallo, Virginia; Bortolini, Maria Cátira; Bonatto, Sandro Luis; Salzano, Francisco Mauro; Hünemeier, Tábita

    2013-01-01

    The relationship between the evolution of genes and languages has been studied for over three decades. These studies rely on the assumption that languages, as many other cultural traits, evolve in a gene-like manner, accumulating heritable diversity through time and being subjected to evolutionary mechanisms of change. In the present work we used genetic data to evaluate South American linguistic classifications. We compared discordant models of language classifications to the current Native American genome-wide variation using realistic demographic models analyzed under an Approximate Bayesian Computation (ABC) framework. Data on 381 STRs spread along the autosomes were gathered from the literature for populations representing the five main South Amerindian linguistic groups: Andean, Arawakan, Chibchan-Paezan, Macro-Jê, and Tupí. The results indicated a higher posterior probability for the classification proposed by J.H. Greenberg in 1987, although L. Campbell's 1997 classification cannot be ruled out. Based on Greenberg's classification, it was possible to date the time of Tupí-Arawakan divergence (2.8 kya), and the time of emergence of the structure between present day major language groups in South America (3.1 kya). PMID:23696865

  12. Identification and lineage genotyping of South American trypanosomes using fluorescent fragment length barcoding.

    PubMed

    Hamilton, P B; Lewis, M D; Cruickshank, C; Gaunt, M W; Yeo, M; Llewellyn, M S; Valente, S A; Maia da Silva, F; Stevens, J R; Miles, M A; Teixeira, M M G

    2011-01-01

    Trypanosoma cruzi and Trypanosoma rangeli are human-infective blood parasites, largely restricted to Central and South America. They also infect a wide range of wild and domestic mammals and are transmitted by a numerous species of triatomine bugs. There are significant overlaps in the host and geographical ranges of both species. The two species consist of a number of distinct phylogenetic lineages. A range of PCR-based techniques have been developed to differentiate between these species and to assign their isolates into lineages. However, the existence of at least six and five lineages within T. cruzi and T. rangeli, respectively, makes identification of the full range of isolates difficult and time consuming. Here we have applied fluorescent fragment length barcoding (FFLB) to the problem of identifying and genotyping T. cruzi, T. rangeli and other South American trypanosomes. This technique discriminates species on the basis of length polymorphism of regions of the rDNA locus. FFLB was able to differentiate many trypanosome species known from South American mammals: T. cruzi cruzi, T. cruzi marinkellei, T. dionisii-like, T. evansi, T. lewisi, T. rangeli, T. theileri and T. vivax. Furthermore, all five T. rangeli lineages and many T. cruzi lineages could be identified, except the hybrid lineages TcV and TcVI that could not be distinguished from lineages III and II respectively. This method also allowed identification of mixed infections of T. cruzi and T. rangeli lineages in naturally infected triatomine bugs. The ability of FFLB to genotype multiple lineages of T. cruzi and T. rangeli together with other trypanosome species, using the same primer sets is an advantage over other currently available techniques. Overall, these results demonstrate that FFLB is a useful method for species diagnosis, genotyping and understanding the epidemiology of American trypanosomes. PMID:21029792

  13. Ancient proteins resolve the evolutionary history of Darwin's South American ungulates.

    PubMed

    Welker, Frido; Collins, Matthew J; Thomas, Jessica A; Wadsley, Marc; Brace, Selina; Cappellini, Enrico; Turvey, Samuel T; Reguero, Marcelo; Gelfo, Javier N; Kramarz, Alejandro; Burger, Joachim; Thomas-Oates, Jane; Ashford, David A; Ashton, Peter D; Rowsell, Keri; Porter, Duncan M; Kessler, Benedikt; Fischer, Roman; Baessmann, Carsten; Kaspar, Stephanie; Olsen, Jesper V; Kiley, Patrick; Elliott, James A; Kelstrup, Christian D; Mullin, Victoria; Hofreiter, Michael; Willerslev, Eske; Hublin, Jean-Jacques; Orlando, Ludovic; Barnes, Ian; MacPhee, Ross D E

    2015-06-01

    No large group of recently extinct placental mammals remains as evolutionarily cryptic as the approximately 280 genera grouped as 'South American native ungulates'. To Charles Darwin, who first collected their remains, they included perhaps the 'strangest animal[s] ever discovered'. Today, much like 180 years ago, it is no clearer whether they had one origin or several, arose before or after the Cretaceous/Palaeogene transition 66.2 million years ago, or are more likely to belong with the elephants and sirenians of superorder Afrotheria than with the euungulates (cattle, horses, and allies) of superorder Laurasiatheria. Morphology-based analyses have proved unconvincing because convergences are pervasive among unrelated ungulate-like placentals. Approaches using ancient DNA have also been unsuccessful, probably because of rapid DNA degradation in semitropical and temperate deposits. Here we apply proteomic analysis to screen bone samples of the Late Quaternary South American native ungulate taxa Toxodon (Notoungulata) and Macrauchenia (Litopterna) for phylogenetically informative protein sequences. For each ungulate, we obtain approximately 90% direct sequence coverage of type I collagen α1- and α2-chains, representing approximately 900 of 1,140 amino-acid residues for each subunit. A phylogeny is estimated from an alignment of these fossil sequences with collagen (I) gene transcripts from available mammalian genomes or mass spectrometrically derived sequence data obtained for this study. The resulting consensus tree agrees well with recent higher-level mammalian phylogenies. Toxodon and Macrauchenia form a monophyletic group whose sister taxon is not Afrotheria or any of its constituent clades as recently claimed, but instead crown Perissodactyla (horses, tapirs, and rhinoceroses). These results are consistent with the origin of at least some South American native ungulates from 'condylarths', a paraphyletic assembly of archaic placentals. With ongoing

  14. The dark side to Donovanosis: color, climate, race and racism in American South venereology.

    PubMed

    Hammar, Lawrence

    1997-01-01

    Medical experimentation on humans with "classic" sexually transmitted diseases (e.g., syphilis, gonorrhea) is not generally well known, but experimentation with others such as Granuloma inguinale, or Donovanosis, is even less so. Endemic to non-existent here, hyper-epidemic there, between 1880 and 1950 Donovanosis was linguistically and morally "constructed" as a disease of poor, sexually profligate, tropical, darkly-skinned persons. It was also experimentally produced on and in African-American patients in many charity hospitals in the American South. This essay analyzes Donovanosis literature of the period that heavily featured skin color, climate and tropicality, venereal sin, and racial susceptibility. It then recounts the history of human experimentation with it, and explains both its linguistic construction and its biomedical experimental history in terms of "disease narratives" produced not only by but for venereologists. PMID:11654562

  15. The role of immigrants in the assembly of the South American rainforest tree flora.

    PubMed Central

    Pennington, R Toby; Dick, Christopher W

    2004-01-01

    The Amazon lowland rainforest flora is conventionally viewed as comprising lineages that evolved in biogeographic isolation after the split of west Gondwana (ca. 100 Myr ago). Recent molecular phylogenies, however, identify immigrant lineages that arrived in South America during its period of oceanic isolation (ca. 100-3 Myr ago). Long-distance sweepstakes dispersal across oceans played an important and possibly predominant role. Stepping-stone migration from Africa and North America through hypothesized Late Cretaceous and Tertiary island chains may have facilitated immigration. An analysis of inventory plot data suggests that immigrant lineages comprise ca. 20% of both the species and individuals of an Amazon tree community in Ecuador. This is more than an order of magnitude higher than previous estimates. We also present data on the community-level similarity between South American and palaeotropical rainforests, and suggest that most taxonomic similarity derives from trans-oceanic dispersal, rather than a shared Gondwanan history. PMID:15519976

  16. A new species of trypanosome, Trypanosoma desterrensis sp. n., isolated from South American bats.

    PubMed

    Grisard, E C; Sturm, N R; Campbell, D A

    2003-09-01

    Trypanosomes isolated from South American bats include the human pathogen Trypanosoma cruzi. Other Trypanosoma spp. that have been found exclusively in bats are not well characterized at the DNA sequence level and we have therefore used the SL RNA gene to differentiate and characterize kinetoplastids isolated from bats in South America. A Trypanosoma sp. isolated from hats in southern Brazil was compared with the geographically diverse isolates T. cruzi marinkellei, T. vespertilionis, and T. dionisii. Analysis of the SL RNA gene repeats revealed size and sequence variability among these bat trypanosomes. We have developed hybridization probes to separate these bat isolates and have analysed the DNA sequence data to estimate their relatedness. A new species, Trypanosoma desterrensis sp. n., is proposed, for which a 5S rRNA gene was also found within the SL RNA repeat. PMID:12964829

  17. Reddish Egret extends its breeding range along the North American Atlantic coast into South Carolina

    USGS Publications Warehouse

    Ferguson, L.M.; Jodice, P.G.R.; Post, W.; Sanders, F.I.

    2005-01-01

    We report the northernmost breeding record of the Reddish Egret (Egretta rufescens) along the North American Atlantic Coast. Nesting activity was first seen in late May 2004, and on 6 July 2004 a nest was discovered with two young chicks on Marsh Island, a barrier island located within Cape Romain National Wildlife Refuge, South Carolina, USA. Reddish Egret nestlings were last observed within 1 m of the nest on 30 July 2004. This represents a northward extension of ca. 450 km in the breeding range of this species and, for the U.S. Atlantic Coast, the only recorded instance of nesting north of Florida.

  18. Applications of a hand-held GPS receiver in South American rain forests

    NASA Technical Reports Server (NTRS)

    Baksh, Michael

    1991-01-01

    A hand-held Global Positioning System receiver was used to determine the precise locations of villages, houses, gardens, and other cultural and environmental features in poorly mapped South American rain forests. The Magellan NAV 1000 unit profides extremely accurate latitude and longitude information, but determination of altitude is problematical. Overall, the receiver effectively allows anthropologists to obtain essential locational data useful for categorizing land uses, mapping tribal boundaries, and other applications in regions where environmental conditions are harsh and/or accessibility is difficult.

  19. Highly Structured Duets in the Song of the South American Hornero

    NASA Astrophysics Data System (ADS)

    Laje, Rodrigo; Mindlin, Gabriel B.

    2003-12-01

    The South American Hornero (Furnarius rufus) is a suboscine bird widely known for its mud-made, oven-looking nest. Beyond their architectural skills, the male and female Horneros sing in highly structured duets. The analysis of field recordings reported in this work reveals that as the male increases the note production rate the female responds by switching to different locking states: the ones predicted by the theory of nonlinear forced oscillators. This gives the duet a most appealing rhythm, and unveils the nonlinear nature of the underlying brain activity needed to generate the song.

  20. Experimental infection of two South American reservoirs with four distinct strains of Trypanosoma cruzi.

    PubMed

    Roellig, Dawn M; McMillan, Katherine; Ellis, Angela E; Vandeberg, John L; Champagne, Donald E; Yabsley, Michael J

    2010-05-01

    Trypanosoma cruzi (Tc), the causative agent of Chagas disease, is a diverse species with 2 primary genotypes, TcI and TcII, with TcII further subdivided into 5 subtypes (IIa-e). This study evaluated infection dynamics of 4 genetically and geographically diverse T. cruzi strains in 2 South American reservoirs, degus (Octodon degus) and grey short-tailed opossums (Monodelphis domestica). Based on prior suggestions of a genotype-host association, we hypothesized that degus (placental) would more readily become infected with TcII strains while short-tailed opossums (marsupial) would be a more competent reservoir for a TcI strain. Individuals (n=3) of each species were intraperitoneally inoculated with T. cruzi trypomastigotes of TcIIa [North America (NA)-raccoon (Procyon lotor) origin], TcI [NA-Virginia opossum (Didelphis virginiana)], TcIIb [South America (SA)-human], TcIIe (SA-Triatoma infestans), or both TcI and TcIIa. Parasitaemias in experimentally infected degus peaked earlier (7-14 days post-inoculation (p.i.)) compared with short-tailed opossums (21-84 days p.i.). Additionally, peak parasitaemias were higher in degus; however, the duration of detectable parasitaemias for all strains, except TcIIa, was greater in short-tailed opossums. Infections established in both host species with all genotypes, except for TcIIa, which did not establish a detectable infection in short-tailed opossums. These results indicate that both South American reservoirs support infections with these isolates from North and South America; however, infection dynamics differed with host and parasite strain. PMID:20128943

  1. The Antillean-South American Collision Zone as Imaged by BOLIVAR Seismic Data

    NASA Astrophysics Data System (ADS)

    Levander, A.; Bezada, M. J.; Niu, F.; Miller, M. S.; Masy, J.; Clark, S. A.; Magnani, M.; Ave Lallemant, H. G.; Pindell, J. L.

    2009-12-01

    Most models for the evolution of the southeastern Caribbean plate boundary invoke a time transgressive collision of the Antilles arc against northern South America (SA) as the Antillean subduction zone rolled back from Colombia to its present location east of Trindad during the Cenozoic. We present seismic images from the BOLIVAR experiment that detail crustal, lithospheric, and upper mantle structures across northern Venezuela resulting from this collision between the Caribbean and South American plates. A combination of seismicity, active seismic profiles, receiver functions, shear wave splits, and surface wave inversions image crustal, lithospheric and upper most mantle structures, while receiver functions and finite-frequency body-wave tomography provide control on deeper structures through the transition zone. We observe a number of first order structures that relate to Caribbean-South American collision: 1) The right-lateral San Sebastian-El Pilar strike-slip system originates at the southeastern corner of the Antillean subduction zone at about (10.75oN, 62.25oW) offshore eastern Venezuela as a subduction-transform edge propagator fault system. As the Atlantic plate descends into the mantle, tearing from the South American plate, it also depresses the edge of the SA continental margin, providing room for coastal mountain building and massive sedimentary basins. 2) After tearing from South America, the Atlantic slab descends rapidly to the transition zone as seen in body wave tomography and receiver function images. 3) The Caribbean plate has been underthrust beneath Colombia and western Venezuela from the west, and now extends as far east as the foreland of the Merida Andes, its western edge roughly paralleling the Bocono fault. 4) The mountains of central and western Venezuela owe much of their elevation to the Caribbean slab lying beneath them. In particular east-directed flat-slab Caribbean subduction beneath westernmost Venezuela has produced the Merida

  2. Agrotis Ochsenheimer (Lepidoptera, Noctuidae): a systematic analysis of South American species.

    PubMed

    San Blas, Germán

    2014-01-01

    The genus Agrotis Ochsenheimer, 1816 (Lepidoptera, Noctuidae) contains about 300 described species distributed worldwide, excepting the Poles. For South America 93 species have been described. Different diagnostic characters have been proposed for species from the northern Hemisphere, mostly from male genitalia. Recently, numerous South American species of the genus have been transferred to other genera. In this work, a systematic revision was undertaken of the South American species of Agrotis, restricting to 20 the number of species of this genus for the region and transferring the other species to different genera and/or synonymizing with other species.Based on a detailed study of the external morphology and genitalia of both sexes, several nomen clatural changes are proposed. New generic synonymy: Mesembreuxoa Hampson = Feltia Walker. New Agrotis synonymies include: Scotia forsteri Köhler = A. propriens (Dyar); Agrotis peruviana hampsoni Draudt, Rhizagrotis triclava Draudt, and Euxoa andina Köhler = A. peruviana (Hampson); Lycophotia achromatica Hampson, Feltia malefida patagiata Aurivillius, Prout and Meyrick, Agrotis psammophila Köhler, and Scotia (Feltia) canietensis Köhler = A. malefida Guenée; Chorizagrotis benefida Draudt = A. experta (Walker); Agrotis livens Köhler and Agrotis capayana Köhler = A. araucaria (Hampson). Species transferred to Feltia Walker tent. include: Scotia aspersula Köhler, n. comb.; Porosagrotis brachystria Hampson, n. comb.; Agrotis carrascoi Köhler, n. comb.; Mesembreuxoa chilensis Hampson, n. comb.; Euxoa clavisigna Dognin, n. comb.; Euxoa conifrons Draudt, n. comb.; Agrotis consternans Hayes, n. comb.; Euxoa coquimbensis Hampson, n. comb.; Mesembreuxoa fasicola Dyar, n. comb.; Chorizagrotis forasmicans Köhler, n. comb.; Agrotis giselae León, n. comb.; Agrotis gypaetina Guenée, n. comb.; Agrotis hispidula Guenée, n. comb.; Euxoa incarum Cockerell, n. comb.; Agrotis india Köhler, n. comb.; Scotia mansa Köhler, n

  3. An international cooperative effort to protect Opuntia cactus resources in the American Southwest and Mexico from the South American cactus moth, Cactoblastis cactorum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The South American Cactus moth, Cactoblastis cactorum, was intentionally introduced to an island in the Caribbean in the 1950’s and eventually made its way to the Florida peninsula by 1989. In 2004, the United States Department of Agriculture’s (USDA) Animal and Plant Health Inspection Service (APH...

  4. Religiosity and Sexual Risk Behaviors Among African American Cocaine Users in the Rural South

    PubMed Central

    Montgomery, Brooke E.E.; Stewart, Katharine E.; Yeary, Karen H.K.; Cornell, Carol E.; Pulley, LeaVonne; Corwyn, Robert; Ounpraseuth, Songthip T.

    2014-01-01

    Purpose Racial and geographic disparities in human immunodeficency virus (HIV) are dramatic and drug use is a significant contributor to HIV risk. Within the rural South, African Americans who use drugs are at extremely high risk. Due to the importance of religion within African American and rural Southern communities, it can be a key element of culturally-targeted health promotion with these populations. Studies have examined religion’s relationship with sexual risk in adolescent populations, but few have examined specific religious behaviors and sexual risk behaviors among drug-using African American adults. This study examined the relationship between well-defined dimensions of religion and specific sexual behaviors among African Americans who use cocaine living in the rural southern United States. Methods Baseline data from a sexual risk reduction intervention for African Americans who use cocaine living in rural Arkansas (N = 205) were used to conduct bivariate and multivariate analyses examining the association between multiple sexual risk behaviors and key dimensions of religion including religious preference, private and public religious participation, religious coping, and God-based, congregation-based, and church leader-based religious support. Findings After adjusting individualized network estimator weights based on the recruitment strategy, different dimensions of religion had inverse relationships with sexual risk behavior, including church leadership support with number of unprotected vaginal/anal sexual encounter and positive religious coping with number of sexual partners and with total number of vaginal/anal sexual encounters. Conclusion Results suggest that specific dimensions of religion may have protective effects on certain types of sexual behavior, which may have important research implications. PMID:24575972

  5. Factors associated with toothache among African American adolescents living in rural South Carolina.

    PubMed

    Yuen, Hon K; Wiegand, Ryan E; Hill, Elizabeth G; Magruder, Kathryn M; Slate, Elizabeth H; Salinas, Carlos F; London, Steven D

    2011-01-01

    The aim of this study is to explore behavioral factors associated with toothache among African American adolescents living in rural South Carolina. Using a self-administered questionnaire, data were collected on toothache experience in the past 12 months, oral hygiene behavior, dental care utilization, and cariogenic snack and nondiet soft drink consumption in a convenience sample of 156 African American adolescents age 10 to 18 years living in rural South Carolina. Univariable and multivariable logistic regression analyses were used to assess the associations between reported toothache experience and sociodemographic variables, oral health behavior, and snack consumption. Thirty-four percent of adolescents reported having toothache in the past 12 months. In univariable modeling, age, dental visit in the last 2 years, quantity and frequency of cariogenic snack consumption, and quantity of nondiet soft drink consumption were each significantly associated with experiencing toothache in the past 12 months (all p values < 0.05). Multivariable logistic regression analysis indicated that younger age, frequent consumption of cariogenic snacks, and number of cans of nondiet soft drink consumed during the weekend significantly increased the odds of experiencing toothache in the past 12 months (all p values ≤ 0.01). Findings indicate age, frequent consumption of cariogenic snacks, and number of cans of nondiet soft drinks are related to toothache in this group. Public policy implications related to selling cariogenic snacks and soft drink that targeting children and adolescents especially those from low income families are discussed. PMID:22085328

  6. ["Candidatus Mycoplasma haemolamae" infections in clinically asymptomatic Austrian South American Camelids].

    PubMed

    Franz, Sonja; Spergser, Joachim; Schwendenwein, Ilse; Stanitznig, Anna; Lambacher, Bianca; Tichy, Alexander; Wittek, Thomas

    2016-01-01

    Reports of CMhl infections in South American Camelids in Europe are only available from the United Kingdom and Switzerland. Knowing that CMhl infections can lead to severe disease resulting in death if combined with other diseases or stress, it was the aim of this study to assess prevalence data from camelids in Austria. In comparison to the previous studies a representative number of camelids was investigated nationwide. Data were assessed due to differences in geographical region, age, sex, species, and origin. A relatively high prevalence of 25.8% was recorded. CMhl was detected significantly more often in alpacas (Vicunja pacos) than in llamas (Lama glama) and more frequently in animals younger than 2 years. Additionally regional differences have been observed, which might be due to climatic differences and/or variations in insect vectors. In this study apperantly clinical healthy animals were shown to be infected with CMhl. Camelids infected with CMhl are a pathogen reservoir. The results of this study indicate different risk levels of infection between llamas and alpacas and between younger and older animals. The data presented underline the necessity of further studies on CMhlI infections in South American Camelids. PMID:27529994

  7. Anthropozoonotic Endoparasites in Free-Ranging “Urban” South American Sea Lions (Otaria flavescens)

    PubMed Central

    Silva, Liliana M. R.; Navarro, Mauricio; Taubert, Anja

    2016-01-01

    The present study represents the first report on the gastrointestinal endoparasite fauna of a free-ranging “urban” colony of South American sea lions (Otaria flavescens) living within the city of Valdivia, Chile. A total of 40 individual faecal samples of South American sea lions were collected during the year 2012 within their natural habitat along the river Calle-Calle and in the local fish market of Valdivia. Coprological analyses applying sodium acetate acetic formalin methanol (SAF) technique, carbol fuchsin-stained faecal smears and Giardia/Cryptosporidium coproantigen ELISAs, revealed infections with 8 different parasites belonging to protozoan and metazoan taxa with some of them bearing anthropozoonotic potential. Thus, five of these parasites were zoonotic (Diphyllobothriidae gen. sp., Anisakidae gen. sp., Giardia, Cryptosporidium, and Balantidium). Overall, these parasitological findings included four new parasite records for Otaria flavescens, that is, Giardia, Cryptosporidium, Balantidium, and Otostrongylus. The current data serve as a baseline for future monitoring studies on anthropozoonotic parasites circulating in these marine mammals and their potential impact on public health. PMID:27051860

  8. Impact of South American heroin on the US heroin market 1993–2004

    PubMed Central

    Ciccarone, Daniel; Unick, George J; Kraus, Allison

    2008-01-01

    Background The past two decades have seen an increase in heroin-related morbidity and mortality in the United States. We report on trends in US heroin retail price and purity, including the effect of entry of Colombian-sourced heroin on the US heroin market. Methods The average standardized price ($/mg-pure) and purity (% by weight) of heroin from 1993 to 2004 was from obtained from US Drug Enforcement Agency retail purchase data for 20 metropolitan statistical areas. Univariate statistics, robust Ordinary Least Squares regression and mixed fixed and random effect growth curve models were used to predict the price and purity data in each metropolitan statistical area over time. Results Over the 12 study years, heroin price decreased 62%. The median percentage of all heroin samples that are of South American origin increased an absolute 7% per year. Multivariate models suggest percent South American heroin is a significant predictor of lower heroin price and higher purity adjusting for time and demographics. Conclusion These analyses reveal trends to historically low-cost heroin in many US cities. These changes correspond to the entrance into and rapid domination of the US heroin market by Colombian-sourced heroin. The implications of these changes are discussed. PMID:19201184

  9. Ovarian follicular morphometry of South American fur seal pups (Arctophoca australis).

    PubMed

    Katz, Helena; Johansson, Olle

    2013-10-01

    The aim of this study was to analyze the morphometric characteristics of ovarian follicles and their distribution in the ovarian cortex in South American fur seal pups (Arctophoca australis). Samples were obtained from animals stranded in the Uruguayan Atlantic coast. Ovaries were dissected, fixed, weighed, and processed by standard histological techniques. Ovarian weight increased with pup age and body length. There was an increase in the diameter of the oocytes (22.24 ± 0.6 to 68.2 ± 5.3 µm), the nuclei (10.04 ± 0.2 to 20.7 ± 1.6 µm), and follicles (30.4 ± 1.2 to 252.6 ± 53.6 µm) of type 1 to type 5 follicles; there was a wide range of variation in the diameter of follicle type 4 and 5. Granulosa layer thickness increased between follicles type 3 and 4, whereas between type 4 and 5 there was a reduction. Thecal layer from follicles type 3 and 4 consisted of 1-2 layers of cells, whereas type 5 showed an increase in thickness (3.13 ± 0.3 to 13.8 ± 5.2 µm). Follicles type 1 and 2 occupied superficial regions within the ovarian cortex while the remaining follicles had a deeper location. These results provide a basis for comparison with females of other age categories as well as follicular dynamics studies in South American fur seals. PMID:23959768

  10. Anthropozoonotic Endoparasites in Free-Ranging "Urban" South American Sea Lions (Otaria flavescens).

    PubMed

    Hermosilla, Carlos; Silva, Liliana M R; Navarro, Mauricio; Taubert, Anja

    2016-01-01

    The present study represents the first report on the gastrointestinal endoparasite fauna of a free-ranging "urban" colony of South American sea lions (Otaria flavescens) living within the city of Valdivia, Chile. A total of 40 individual faecal samples of South American sea lions were collected during the year 2012 within their natural habitat along the river Calle-Calle and in the local fish market of Valdivia. Coprological analyses applying sodium acetate acetic formalin methanol (SAF) technique, carbol fuchsin-stained faecal smears and Giardia/Cryptosporidium coproantigen ELISAs, revealed infections with 8 different parasites belonging to protozoan and metazoan taxa with some of them bearing anthropozoonotic potential. Thus, five of these parasites were zoonotic (Diphyllobothriidae gen. sp., Anisakidae gen. sp., Giardia, Cryptosporidium, and Balantidium). Overall, these parasitological findings included four new parasite records for Otaria flavescens, that is, Giardia, Cryptosporidium, Balantidium, and Otostrongylus. The current data serve as a baseline for future monitoring studies on anthropozoonotic parasites circulating in these marine mammals and their potential impact on public health. PMID:27051860

  11. Review of seismic gaps and gap model for the South American subduction zone

    NASA Astrophysics Data System (ADS)

    Roth, Frank; Dahm, Torsten; Hainzl, Sebastian

    2016-04-01

    The seismic gap hypothesis describes a long-period decrease of the probability of earthquake occurrence after major earthquakes, as a consequence of the induced stress shadow. The gap model assumes that the continuous build-up of tectonic strain and stress is released by characteristic major earthquakes. The size of the characteristic earthquakes is for instance controlled by structural heterogeneities or the geometry of the plate boundaries. The gap model is commonly accepted by geologists and a fundamental assumption of our approaches to estimate seismic hazard and time dependent earthquake probability. Interestingly, systematic and rigorous tests to verify the seismic gap model have often failed. In this study we analyze the historical record of major earthquakes at the South American plate boundary with a special look to seismic gaps. The aim of our study is to compare and proof different seismic gap models. We discuss whether the characteristic earthquakes assumption is justified for the South American plate boundary. Two different gap models are discussed: (a) a traditional quasi-periodic recurrence model involving time dependent conditional occurrence probabilities, and (b) a new model describing earthquake rates by rate and state seismicity models considering the estimated spatial pattern of stress drop during major earthquakes.

  12. Annual South American forest loss estimates based on passive microwave remote sensing (1990-2010)

    NASA Astrophysics Data System (ADS)

    van Marle, M. J. E.; van der Werf, G. R.; de Jeu, R. A. M.; Liu, Y. Y.

    2015-07-01

    Consistent forest loss estimates are important to understand the role of forest loss and deforestation in the global carbon cycle, for biodiversity studies, and to estimate the mitigation potential of reducing deforestation. To date, most studies have relied on optical satellite data and new efforts have greatly improved our quantitative knowledge on forest dynamics. However, most of these studies yield results for only a relatively short time period or are limited to certain countries. We have quantified large-scale forest losses over a 21 year period (1990-2010) in the tropical biomes of South America using remotely sensed vegetation optical depth (VOD). This passive microwave satellite-based indicator of vegetation water content and vegetation density has a much coarser spatial resolution than optical but its temporal resolution is higher and VOD is not impacted by aerosols and cloud cover. We used the merged VOD product of the Advanced Microwave Scanning Radiometer (AMSR-E) and Special Sensor Microwave Imager (SSM/I) observations, and developed a change detection algorithm to quantify spatial and temporal variations in forest loss dynamics. Our results compared favorably to the newly developed Global Forest Change (GFC) maps based on Landsat data and available for the 2001 onwards period (r2 = 0.90 when comparing annual country-level estimates), which allowed us to convert our results to forest loss area and compute these from 1990 onwards. We found that South American forest exhibited substantial interannual variability without a clear trend during the 1990s, but increased from 2000 until 2004. After 2004, forest loss decreased again, except for two smaller peaks in 2007 and 2010. For a large part, these trends were driven by changes in Brazil, which was responsible for 56 % of the total South American forest loss over our study period according to our results. One of the key findings of our study is that while forest losses decreased in Brazil after 2005

  13. Annual South American forest loss estimates based on passive microwave remote sensing (1990-2010)

    NASA Astrophysics Data System (ADS)

    van Marle, M. J. E.; van der Werf, G. R.; de Jeu, R. A. M.; Liu, Y. Y.

    2016-02-01

    Consistent forest loss estimates are important to understand the role of forest loss and deforestation in the global carbon cycle, for biodiversity studies, and to estimate the mitigation potential of reducing deforestation. To date, most studies have relied on optical satellite data and new efforts have greatly improved our quantitative knowledge on forest dynamics. However, most of these studies yield results for only a relatively short time period or are limited to certain countries. We have quantified large-scale forest loss over a 21-year period (1990-2010) in the tropical biomes of South America using remotely sensed vegetation optical depth (VOD). This passive microwave satellite-based indicator of vegetation water content and vegetation density has a much coarser spatial resolution than optical data but its temporal resolution is higher and VOD is not impacted by aerosols and cloud cover. We used the merged VOD product of the Advanced Microwave Scanning Radiometer (AMSR-E) and Special Sensor Microwave Imager (SSM/I) observations, and developed a change detection algorithm to quantify spatial and temporal variations in forest loss dynamics. Our results compared reasonably well with the newly developed Landsat-based Global Forest Change (GFC) maps, available for the 2001 onwards period (r2 = 0.90 when comparing annual country-level estimates). This allowed us to convert our identified changes in VOD to forest loss area and compute these from 1990 onwards. We also compared these calibrated results to PRODES (r2 = 0.60 when comparing annual state-level estimates). We found that South American forest exhibited substantial interannual variability without a clear trend during the 1990s, but increased from 2000 until 2004. After 2004, forest loss decreased again, except for two smaller peaks in 2007 and 2010. For a large part, these trends were driven by changes in Brazil, which was responsible for 56 % of the total South American forest loss area over our study

  14. Features of the distribution of hydrocarbon accumulations in lithologically different-type deposits at the ancient continental margins of the North American and South American platforms

    NASA Astrophysics Data System (ADS)

    Zabanbark, A.; Lobkovskiy, L. I.

    2015-03-01

    Lithologically diverse sedimentary complexes were formed within the North and South American platforms. The most general groups of the sediments are distinguished as follows: continental (alluvial, limnic), deltaic, shallow-marine, and deepwater—for the terrigeneous formations, reef limestones and limestones of other origins (oolitic, algaes, etc.), and dolomites—for carbonate varieties. In addition to this, tuffs, tuff-sandstones, and crystalline schists (quartzites) were studied separately. The lasts were marked only in the Permian Basin. The comparative analysis of the sedimentary basins located in the peripheral parts of the North American and South American platforms showed the following: the most important stage in the evolution of the North American platform is the first stage of existence of the ancient Paleozoic continental margins, which developed under passive tectonic conditions and determined its future potential of oil and gas bearing. At this stage, the main resources of oil and gas hydrocarbons are concentrated in carbonate rocks. As for the sedimentary basins located on the margins of the South American platform, the second stage is the most important stage in their evolution when the foredeeps were formed and developed laying on the earlier structures. This period is related to the oil and gas bearing potential of the basins on the margins of the South American platform. For both platforms, a common circumstance is that, at the second stage of development of all the sedimentary basins, all the resources of hydrocarbons are focused in the terrigeneous sediments.The stratigraphic range of oil and gas occurrence in the basins of the ancient continental margins is determined by the following regularity: the fold structures is younger confining these margins, the age range of the oil and gas reservoirs is broader.

  15. Correlates of Perceived Risk of Developing Cancer among African-Americans in South Los Angeles

    PubMed Central

    Lucas-Wright, Anna; Bazargan, Mohsen; Jones, Loretta; Vadgama, Jaydutt V.; Vargas, Roberto; Sarkissyan, Marianna; Smith, James; Yazdanshenas, Hamed; Maxwell, Annette E.

    2013-01-01

    Background There are differences in cancer-risk perception among racial/ethnic groups that may affect health risk behaviors. Methods Using a community partnered-participatory research approach, we conducted a survey on cancer screening, risk behaviors, and related knowledge/attitudes within 11 churches in South Los Angeles with predominantly African-American parishioners. This analysis examines correlates of perceived risk of developing cancer among 755African American adults. Results Almost 15% of participants indicated higher perceived risk for cancer compared to the average man/woman of the same age, 38% indicated same risk, whereas 48% perceived lower risk. Sixty-nine individuals (9%) reported a cancer history and 63% reported at least one blood relative with cancer. Controlling for demographic characteristics and healthcare access, participants who reported higher risk of cancer had higher level of cancer-related knowledge; were current and ex-smokers; had poorer health status; had a blood relative with cancer; had a cancer history; and had discussed their risk of cancer with their doctor. The bivariate association between high perceived cancer risk and lack of exercise and obesity disappeared after adjusting for demographic characteristics and perceived health status. Conclusions Our data suggest that a substantial proportion of African Americans in South Los Angeles may underestimate their cancer risk. Additionally, lack of exercise and obesity are not recognized as independent cancer risk factors as much as smoking and personal and family history of cancer. Next steps will be to inform participating churches about our findings and explore their interest in taking steps to reduce health risk behaviors among their parishioners. PMID:24026303

  16. Cefazolin high-inoculum effect in methicillin-susceptible Staphylococcus aureus from South American hospitals

    PubMed Central

    Rincón, Sandra; Reyes, Jinnethe; Carvajal, Lina Paola; Rojas, Natalia; Cortés, Fabián; Panesso, Diana; Guzmán, Manuel; Zurita, Jeannete; Adachi, Javier A.; Murray, Barbara E.; Nannini, Esteban C.; Arias, Cesar A.

    2013-01-01

    Objectives Clinical failures with cefazolin have been described in high-inoculum infections caused by methicillin-susceptible Staphylococcus aureus (MSSA) producing type A β-lactamase. We investigated the prevalence of the cefazolin inoculum effect (InE) in MSSA from South American hospitals, since cefazolin is used routinely against MSSA due to concerns about the in vivo efficacy of isoxazolyl penicillins. Methods MSSA isolates were recovered from bloodstream (n = 296) and osteomyelitis (n = 68) infections in two different multicentre surveillance studies performed in 2001–02 and 2006–08 in South American hospitals. We determined standard-inoculum (105cfu/mL) and high-inoculum (107 cfu/mL) cefazolin MICs. PFGE was performed on all isolates that exhibited a cefazolin InE. Multilocus sequence typing (MLST) and sequencing of part of blaZ were performed on representative isolates. Results The overall prevalence of the cefazolin InE was 36% (131 isolates). A high proportion (50%) of MSSA isolates recovered from osteomyelitis infections exhibited the InE, whereas it was observed in 33% of MSSA recovered from bloodstream infections. Interestingly, Ecuador had the highest prevalence of the InE (45%). Strikingly, 63% of MSSA isolates recovered from osteomyelitis infections in Colombia exhibited the InE. MLST revealed that MSSA isolates exhibiting the InE belonged to diverse genetic backgrounds, including ST5, ST8, ST30 and ST45, which correlated with the prevalent methicillin-resistant S. aureus clones circulating in South America. Types A (66%) and C (31%) were the most prevalent β-lactamases. Conclusions Our results show a high prevalence of the cefazolin InE associated with type A β-lactamase in MSSA isolates from Colombia and Ecuador, suggesting that treatment of deep-seated infections with cefazolin in those countries may be compromised. PMID:23794599

  17. Knowledge and Screening of Head and Neck Cancer Among American Indians in South Dakota

    PubMed Central

    Deschler, Daniel; Sargent, Michele; Emerick, Kevin; Guadagnolo, B. Ashleigh; Petereit, Daniel

    2015-01-01

    Objectives. We established the level of awareness of risk factors and early symptoms of head and neck cancer among American Indians in South Dakota and determined whether head and neck cancer screening detected clinical findings in this population. Methods. We used the European About Face survey. We added questions about human papillomavirus, a risk factor for head and neck cancer, and demographics. Surveys were administered at 2 public events in 2011. Participants could partake in a head and neck cancer screening at the time of survey administration. Results. Of the 205 American Indians who completed the survey, 114 participated in the screening. Mean head and neck cancer knowledge scores were 26 out of 44. Level of education was the only factor that predicted higher head and neck cancer knowledge (b = 0.90; P = .01). Nine (8%) people had positive head and neck cancer screening examination results. All abnormal clinical findings were in current or past smokers (P = .06). Conclusions. There are gaps in American Indian knowledge of head and neck cancer risk factors and symptoms. Community-based head and neck cancer screening in this population is feasible and may be a way to identify early abnormal clinical findings in smokers. PMID:25320895

  18. Widespread pollution of the South American atmosphere predates the industrial revolution by 240 y.

    PubMed

    Uglietti, Chiara; Gabrielli, Paolo; Cooke, Colin A; Vallelonga, Paul; Thompson, Lonnie G

    2015-02-24

    In the Southern Hemisphere, evidence for preindustrial atmospheric pollution is restricted to a few geological archives of low temporal resolution that record trace element deposition originating from past mining and metallurgical operations in South America. Therefore, the timing and the spatial impact of these activities on the past atmosphere remain poorly constrained. Here we present an annually resolved ice core record (A.D. 793-1989) from the high-altitude drilling site of Quelccaya (Peru) that archives preindustrial and industrial variations in trace elements. During the precolonial period (i.e., pre-A.D. 1532), the deposition of trace elements was mainly dominated by the fallout of aeolian dust and of ash from occasional volcanic eruptions, indicating that metallurgic production during the Inca Empire (A.D. 1438-1532) had a negligible impact on the South American atmosphere. In contrast, a widespread anthropogenic signal is evident after around A.D. 1540, which corresponds with the beginning of colonial mining and metallurgy in Peru and Bolivia, ∼240 y before the Industrial Revolution. This shift was due to a major technological transition for silver extraction in South America (A.D. 1572), from lead-based smelting to mercury amalgamation, which precipitated a massive increase in mining activities. However, deposition of toxic trace metals during the Colonial era was still several factors lower than 20th century pollution that was unprecedented over the entirety of human history. PMID:25675506

  19. Cretaceous sequence stratigraphy of the Northern South American Passive Margin: Implications for tectonic evolution

    SciTech Connect

    Kauffman, E.G.; Villamil, T.; Johnson, C.C. )

    1993-02-01

    The passive margin of northern South America, from Colombia to northeastern Venezuela, was relatively stable through the Cretaceous and only broadly affected by the entry of the Caribbean Plate into the Protocaribbean Basin. This region offers a unique opportunity to test the relative effects of global sealevel change, autocyclic sedimentologic processed, and regional tectonics in shaping the stratigraphic record of Cretaceous passive margins. High-resolution stratigraphic studies of Colombia and Venezuela have established a precise system of regional chronology and correlation with resolution <1 Ma (50-500 ka for the middle Cretaceous). This allows precise separation of allocyclic and autocyclic controls on facies development. This new chronology integrates assemblage zone biostratigraphy with event/cycle chronostratigraphy. Newly measured Cretaceous sections in Venezuela and throughout Colombia are calibrated to this new chronology, and sequence stratigraphic units independently defined to the third-order of resolution. Graphic correlation of all sections is used to identify sequences with regional stratigraphic expression, and those which correlate to sequence stratigraphic standards of North America, Europe and the global cycles of Hag et al. (1988). 50-60 percent of the stratigraphic sequences across the South American passive margin correlate to other continents and to the global sequence stratigraphic standard, reflecting strong eustatic influence on Cretaceous sedimentation across northern South America. The remaining sequences in this region reflect tectonic modification of the passive margin and autocyclic sedimentary processes.

  20. Widespread pollution of the South American atmosphere predates the industrial revolution by 240 years

    NASA Astrophysics Data System (ADS)

    Uglietti, Chiara; Gabrielli, Paolo; Cooke, Colin; Vallelonga, Paul; Thompson, Lonnie

    2015-04-01

    In the Southern Hemisphere, evidence for preindustrial atmospheric pollution is restricted to a few geological archives of low temporal resolution that record trace element deposition originating from past mining and metallurgical operations in South America. Therefore the timing and the spatial impact of these activities on the past atmosphere remain poorly constrained. Here we present an annually resolved ice-core record (793-1989 AD) from the high altitude drilling site of Quelccaya (Peru) that archives preindustrial and industrial variations in trace elements. During the pre-colonial period (i.e., pre-1532 AD), the deposition of trace elements was mainly dominated by the fallout of aeolian dust and of ash from occasional volcanic eruptions indicating that metallurgic production during the Inca Empire (1438-1532 AD) had a negligible impact on the South American atmosphere. In contrast, a widespread anthropogenic signal is evident after 1540 AD, which corresponds with the beginning of colonial mining and metallurgy in Peru and Bolivia, 240 years prior to the Industrial Revolution. This shift was due to a major technological transition for silver extraction in South America (1572 AD), from lead-based smelting to mercury amalgamation, which precipitated a massive increase in mining activities. However, deposition of toxic trace metals during the Colonial era was still several factors lower than 20th century pollution that was unprecedented over the entirety of human history.

  1. Widespread pollution of the South American atmosphere predates the industrial revolution by 240 y

    PubMed Central

    Uglietti, Chiara; Gabrielli, Paolo; Cooke, Colin A.; Vallelonga, Paul; Thompson, Lonnie G.

    2015-01-01

    In the Southern Hemisphere, evidence for preindustrial atmospheric pollution is restricted to a few geological archives of low temporal resolution that record trace element deposition originating from past mining and metallurgical operations in South America. Therefore, the timing and the spatial impact of these activities on the past atmosphere remain poorly constrained. Here we present an annually resolved ice core record (A.D. 793–1989) from the high-altitude drilling site of Quelccaya (Peru) that archives preindustrial and industrial variations in trace elements. During the precolonial period (i.e., pre-A.D. 1532), the deposition of trace elements was mainly dominated by the fallout of aeolian dust and of ash from occasional volcanic eruptions, indicating that metallurgic production during the Inca Empire (A.D. 1438−1532) had a negligible impact on the South American atmosphere. In contrast, a widespread anthropogenic signal is evident after around A.D. 1540, which corresponds with the beginning of colonial mining and metallurgy in Peru and Bolivia, ∼240 y before the Industrial Revolution. This shift was due to a major technological transition for silver extraction in South America (A.D. 1572), from lead-based smelting to mercury amalgamation, which precipitated a massive increase in mining activities. However, deposition of toxic trace metals during the Colonial era was still several factors lower than 20th century pollution that was unprecedented over the entirety of human history. PMID:25675506

  2. Characterization of the faecal bacterial community of wild young South American (Arctocephalus australis) and Subantarctic fur seals (Arctocephalus tropicalis).

    PubMed

    Medeiros, Aline Weber; Giongo, Adriana; Valdez, Fernanda P; Blaese de Amorin, Derek; Tavares, Maurício; d'Azevedo, Pedro A; Franco, Ana Claudia; Frazzon, Jeverson; Frazzon, Ana P G

    2016-03-01

    The microbiota of wild marine mammals is poorly understood, perhaps due to the migratory habits of some species and the difficulty in obtaining samples. Using high-throughput sequencing, the present study examines the faecal bacterial community of wild young South American (Arctocephalus australis) and Subantarctic fur seals (A. tropicalis). Faecal samples from South American (n = 6) and Subantarctic fur seals (n = 4) found dead along the south coast of Brazil were collected. Sequences were assigned to taxa using the Ribosomal Database Project-Bayesian classifier. Diversity of the microbiota was assessed by categorization of sequence reads into operational taxonomic units. Results indicate that Firmicutes (88.556%-84.016%) was the predominant phylum in South American and Subantarctic fur seals. The distribution of Actinobacteria and Proteobacteria varied according to the fur seal species. Fusobacteria and Bacteroidetes represented less than 1% of the sequences. The most abundant order in both fur seals was Clostridiales (88.64% and 87.49%). Individual variable incidences were observed in the composition of family among the fur seals, though the families Lachnospiraceae, Peptostreptococcaceae, Ruminococcaceae and Coriobacteriaceae were more prevalent. This study provides insight into the faecal bacterial community of wild young South American and Subantarctic fur seals. PMID:26880785

  3. LULAC v. Richards: The Class Action Lawsuit That Prompted the South Texas Border Initiative and Enhanced Access to Higher Education for Mexican Americans Living along the South Texas Border

    ERIC Educational Resources Information Center

    Ortegon, Ricardo Ray

    2014-01-01

    This case study examined the trials and tribulations a predominantly Mexican-American community in South Texas went through to obtain higher education opportunities for its residents. This study focuses on the "LULAC v. Richards" lawsuit and the South Texas Border Initiative. In 1987, the Mexican American Legal Defense and Educational…

  4. Impacts of American Agricultural Education Student Teachers on Eleven Community Members in a New South Wales, Australia Community: A Qualitative Study

    ERIC Educational Resources Information Center

    Bunch, Tera; Stephens, Carrie; Hart, William

    2011-01-01

    The purpose of this study was to evaluate the influences of American agricultural education student teachers on a rural community in New South Wales, Australia. The study analyzed interviews with eleven participants of the American student teacher program in a rural New South Wales community. Results of the study were formulated by two…

  5. Quantifying the humanitarian and economic impact of earthquakes on South American capital cities (Invited)

    NASA Astrophysics Data System (ADS)

    Zoback, M. L.; Cabrera, C.; Pomonis, A.; Baca, A.; Brunner, I.; Cheung, G.; Chen, A.; Nagel, B.; Carrasco, S.

    2009-12-01

    By 2000, an estimated 80% of South America’s population lived in urban areas (Veblen et al., The Physical Geography of South America, Oxford University Press, 2007). A significant fraction of those urban dwellers resides in the capital cities which are major economic centers and act as magnets for rural poor and refugees. This population concentration includes many residents living in extreme poverty in substandard and informal housing, often on the margins of these capital cities and sometimes on steep slopes, greatly compounding the vulnerability to natural hazards. We are analyzing the humanitarian and economic risk for six of the seismically most-at-risk South American capitals along the northern and western plate boundaries of South America: Caracas, Venezuela; Bogotá, Colombia; Quito, Ecuador; Lima, Perú; La Paz, Bolivia; and Santiago, Chile. Impacts are provided in the form of expected losses for a specific “likely” scenario earthquake and in a probabilistic format using exceedance probability curves (probability of exceeding a given loss in different return periods). Impacts to be quantified include: total economic losses, potential fatalities, potential serious injuries, and the number of displaced households. Probabilistic seismic hazard was developed in collaboration with numerous South American experts and includes subduction interface, intraslab, background crustal and, where available, active fault sources. A significant challenge for this study is to accurately account for the exposure and vulnerability of populations living in the informal, shanty areas. Combining analysis of aerial imagery and on-the-ground reconnaissance, we define between 20-30 “inventory districts” of relatively uniform construction styles within each capital. Statistical distributions of the different construction types and their characteristics (height, occupancy, year built, average value) are estimated for each district. In addition, working with local graduate

  6. Morphological divergence in a continental adaptive radiation: South American ovenbirds of the genus Cinclodes

    USGS Publications Warehouse

    Rader, Jonathan A.; Dillon, Michael E.; Chesser, R. Terry; Sabat, Pablo; Martinez del Rio, Carlos

    2015-01-01

    Cinclodes is an ecologically diverse genus of South American passerine birds and represents a case of continental adaptive radiation along multiple axes. We investigated morphological diversification in Cinclodes using a comprehensive set of morphometric measurements of study skins. Principal component analysis identified 2 primary axes of morphological variation: one describing body size and a second capturing differences in wing-tip shape and toe length. Phylogenetic analyses of the first principal component suggest an early divergence ofCinclodes into 2 main clades characterized by large and small body sizes. We suggest that 2 morphological outliers within these main clades (C. antarcticus and C. palliatus) may be cases of island gigantism and that a third (C. patagonicus) may reflect ecological character displacement. Despite its ecological and physiological diversity, the genus Cinclodes does not appear to show morphological diversity beyond what is typical of other avian genera.

  7. South American camelid illegal traffic detection by means of molecular markers.

    PubMed

    Di Rocco, F; Posik, D M; Ripoli, M V; Díaz, S; Maté, M L; Giovambattista, G; Vidal-Rioja, L

    2011-11-01

    South American camelids comprise the wild species guanaco and vicuña and their respective domestic relatives llama and alpaca. The aim of the present study was to determine by DNA analysis to which of these species belong a herd of camelids confiscated from a llama breeder but alleged to be alpacas by the prosecution, and to evaluate the usefulness of mitochondrial and autosomal DNA markers to solve judicial cases involving camelid taxa. Cytochrome b and cytochrome oxidase I mitochondrial genes and 7 STR were analyzed in 25 confiscated samples. Mitochondrial results were inconclusive because 18 of the sequestered samples presented haplotypes that corresponded to the guanaco haplogroup and the remaining seven belonged to a vicuña linage. Microsatellite data of casework samples and llama reference samples revealed different genetic profiles by the presence of private alleles at two microsatellites suggesting that the confiscated animals could be alpaca, or at least alpaca hybrids instead of pure llama. PMID:21982877

  8. Clinical management of potential ibuprofen toxicosis in a South American red-footed tortoise (Geochelone carbonaria).

    PubMed

    Gladden, Juliet N

    2006-09-01

    This article describes the clinical management of potential ibuprofen toxicosis in South American red-footed tortoise (Geochelone carbonaria). A 2.5-year-old, 0.78-kg Geochelone carbonaria tortoise was presented to the emergency clinic after ingesting solubilized ibuprofen (200 mg) in a gelatin capsule. Treatment on initial presentation consisted of esophagostomy tube placement for gastric lavage and activated charcoal administration, intravenous and intraosseous fluid therapy, and administration of gastrointestinal protectants (sucralfate and famotidine). The tortoise was discharged to the owners. Although follow-up diagnostic monitoring was minimal because of owner compliance, the patient was noted to be alive and in reasonable health 1 year after initial presentation. This is the first report on the management of potential nonsteroidal anti-inflammatory drug toxicosis in any chelonian species. PMID:16931380

  9. History at the table: conflict in planning in a community in the rural American South.

    PubMed

    Messinger, Lori

    2006-06-01

    This article is a case study of problems that emerged during the planning of an anti-poverty program in a community in the rural American South in the early 1990s. Issues of racism, sexism, and classism in the planning process are discussed as they are informed by the national welfare reform rhetoric of the time, a local context of historical and current White racism, and the historical and current identity positions of the local Black planners. The author argues that understanding local history is a vital component in planning and implementing social programs. The article offers an analysis of the deployment of power in the planning of social change projects that can be used to develop inclusive planning processes that are responsive to the needs of economically and socially oppressed populations. PMID:16786413

  10. Preparing for Rectal Microbicides: Sociocultural Factors Affecting Product Uptake Among Potential South American Users

    PubMed Central

    Kinsler, Janni J.; Imrie, John; Nureña, César R.; Ruiz, Lucía; Galarza, Luis Fernando; Sánchez, Jorge; Cunningham, William E.

    2014-01-01

    Objectives. We examined views on rectal microbicides (RMs), a potential HIV prevention option, among men who have sex with men and transgender women in 3 South American cities. Methods. During September 2009 to September 2010, we conducted 10 focus groups and 36 in-depth interviews (n = 140) in Lima and Iquitos, Peru, and Guayaquil, Ecuador, to examine 5 RM domains: knowledge, thoughts and opinions about RM as an HIV prevention tool, use, condoms, and social concerns. We coded emergent themes in recorded and transcribed data sets and extracted representative quotes. We collected sociodemographic information with a self-administered questionnaire. Results. RM issues identified included limited knowledge; concerns regarding plausibility, side effects, and efficacy; impact on condom use; target users (insertive vs receptive partners); and access concerns. Conclusions. Understanding the sociocultural issues affecting RMs is critical to their uptake and should be addressed prior to product launch. PMID:24825222

  11. Prehistoric earthquakes on the Caribbean-South American plate boundary, central Range Fault, Trinidad

    USGS Publications Warehouse

    Prentice, Carol S.; Crosby, Christopher J.; Weber, John C.; Ragona, Daniel

    2010-01-01

    Recent geodetic studies suggest that the Central Range fault is the principal plate-boundary structure accommodating strike-slip motion between the Caribbean and South American plates. Our study shows that the fault forms a topographically prominent lineament in central Trinidad. Results from a paleoseismic investigation at a site where Holocene sediments have been deposited across the Central Range fault indicate that it ruptured the ground surface most recently between 2710 and 550 yr B.P. If the geodetic slip rate of 9–15 mm/yr is representative of Holocene slip rates, our paleoseismic data suggest that at least 4.9 m of potential slip may have accumulated on the fault and could be released during a future large earthquake (M > 7).

  12. Prehistoric earthquakes on the Caribbean-South American plate boundary, central range fault, Trinidad

    USGS Publications Warehouse

    Prentice, C.S.; Weber, J.C.; Crosby, C.J.; Ragona, D.

    2010-01-01

    Recent geodetic studies suggest that the Central Range fault is the principal plate-boundary structure accommodating strike-slip motion between the Caribbean and South American plates. Our study shows that the fault forms a topographically prominent lineament in central Trinidad. Results from a paleoseismic investigation at a site where Holocene sediments have been deposited across the Central Range fault indicate that it ruptured the ground surface most recently between 2710 and 550 yr B.P. If the geodetic slip rate of 9-15 mm/yr is representative of Holocene slip rates, our paleoseismic data suggest that at least 4.9 m of potential slip may have accumulated on the fault and could be released during a future large earthquake (M > 7). ?? 2010 Geological Society of America.

  13. Complex networks identify spatial patterns of extreme rainfall events of the South American Monsoon System

    NASA Astrophysics Data System (ADS)

    Boers, Niklas; Bookhagen, Bodo; Marwan, Norbert; Kurths, Jürgen; Marengo, José

    2013-08-01

    We investigate the spatial characteristics of extreme rainfall synchronicity of the South American Monsoon System (SAMS) by means of Complex Networks (CN). By introducing a new combination of CN measures and interpreting it in a climatic context, we investigate climatic linkages and classify the spatial characteristics of extreme rainfall synchronicity. Although our approach is based on only one variable (rainfall), it reveals the most important features of the SAMS, such as the main moisture pathways, areas with frequent development of Mesoscale Convective Systems (MCS), and the major convergence zones. In addition, our results reveal substantial differences between the spatial structures of rainfall synchronicity above the 90th and above the 95th percentiles. Most notably, events above the 95th percentile contribute stronger to MCS in the La Plata Basin.

  14. Adhesive and invasive capacities of Edwarsiella tarda isolated from South American sea lion

    PubMed Central

    Fernández, Araceli; Villanueva, María Paz; González, Mario; Fernández, Fabiola; Latif, Fadua; Flores, Sandra Nonier; Fernández, Heriberto

    2014-01-01

    Edwarsiella tarda is a zoonotic bacterium that can be isolated from humans, animals and the environment. Although E. tarda is primarily considered a fish pathogen, it is the only species of its genus considered to be pathogenic for humans as well. A survey of zoonotic intestinal bacteria in fresh feces from South American sea lions (SASL) Otaria flavescens, reported E. tarda as the most frequently isolated species. In this study, we used HEp-2 cells to establish in vitro the adherence and invasive ability of 17 E. tarda strains isolated from SASL fecal material. All the strains were able to adhere and invade HEp-2 cells with adhesion and invasion percentages ranging from 56 to 100% and 21 to 74%, respectively. Despite the expression of these pathogenic factors, further investigation is needed to determine whether this bacterium could play a role as primary pathogen for this and other species of pinnipeds. PMID:25477948

  15. Blood oxygen affinity increases during digestion in the South American rattlesnake, Crotalus durissus terrificus.

    PubMed

    Bovo, Rafael P; Fuga, Adriana; Micheli-Campbell, Mariana A; Carvalho, José E; Andrade, Denis V

    2015-08-01

    Digesting snakes experience massive increases in metabolism that can last for many days and are accompanied by adjustments in the oxygen transport cascade. Accordingly, we examined the oxygen-binding properties of the blood in the South American rattlesnake (Crotalus durissus terrificus) during fasting and 24 and 48h after the snakes have ingested a rodent meal corresponding to 15% (±2%) of its own body mass. In general, oxygen-hemoglobin (Hb-O2) affinity was significantly increased 24h post-feeding, and then returned toward fasting values within 48h post-feeding. Content of organic phosphates ([NTP] and [NTP]/[Hb]), hemoglobin cooperativity (Hill's n), and Bohr Effect (ΔlogP50/ΔpH) were not affected by feeding. The postprandial increase in Hb-O2 affinity in the South American rattlesnake can be almost entirely ascribed by the moderate alkaline tide that follows meal ingestion. In general, digesting snakes were able to regulate blood metabolites at quite constant levels (e.g., plasma osmolality, lactate, glucose, and total protein levels). The level of circulating lipids, however, was considerably increased, which may be related to their mobilization, since lipids are known to be incorporated by the enterocytes after snakes have fed. In conclusion, our results indicate that the exceptional metabolic increment exhibited by C. d. terrificus during meal digestion is entirely supported by the aerobic pathways and that among the attending cardiorespiratory adjustments, pulmonary Hb-O2 loading is likely improved due to the increment in blood O2 affinity. PMID:25446935

  16. Microseismicity evidence for subduction of the Caribbean plate beneath the South American Plate in northwestern Venezuela

    NASA Astrophysics Data System (ADS)

    PéRez, Omar J.; Jaimes, Martha A.; Garciacaro, Emilio

    1997-08-01

    Over 1100 microearthquakes with body wave magnitude mb<4 have been located in western Venezuela and the southwestern Caribbean region since the installation in 1980 of the Venezuelan Seismological Array, together with 120 events of mb≥4, one of them with surface wave magnitude Ms˜6. This tectonically complex region is part of the boundary between the Caribbean and the South American plates. The main seismically active feature inland in western Venezuela is the northeast striking, 600-km long, 100-km wide, right-lateral strike-slip Boconó fault zone along the Venezuelan Andes. About 80% of the earthquakes located in the entire region in the period 1980-mid-1995 have occurred on this fault zone, at focal depths <20 km. Microearthquake activity at lower rates also occurs northwest of the Venezuelan Andes, both in the continental and Caribbean sea regions. Part of this activity takes place at depths down to ˜150 km. Northwest oriented seismicity depth profiles show the existence of a Benioff zone dipping to the southeast beneath northwestern Venezuela and northern Colombia. This indicates the presence of a northeast striking, southeast dipping subducted slab of the Caribbean plate beneath the South American plate. Hypocentral locations show that the northeastern end of this subduction occurs northwest of the Curaçao-Aruba region, in the vicinity of a northwest trending, right-lateral strike-slip fault zone that joins up with the northeastern end of the Boconó fault zone. This latter place turns out to be the western end of the east-west striking San Sebastián fault along the Venezuelan coast.

  17. A comparative analysis of prenatal care and fetal growth in eight South American countries.

    PubMed

    Woodhouse, Cristina; Lopez Camelo, Jorge; Wehby, George L

    2014-01-01

    There has been little work that comprehensively compared the relationship between prenatal care and infant health across multiple countries using similar data sources and analytical models. Such comparative analyses are useful for understanding the background of differences in infant health between populations. We evaluated the association between prenatal care visits and fetal growth measured by birth weight (BW) in grams or low birth weight (<2500 grams; LBW) adjusted for gestational age in eight South American countries using similarly collected data across countries and the same analytical models. OLS and logistic regressions were estimated adjusting for a large set of relevant infant, maternal, and household characteristics and birth year and hospital fixed effects. Birth data were acquired from 140 hospitals that are part of the Latin American Collaborative Study of Congenital Malformations (ECLAMC) network. The analytical sample included 56,014 live-born infants (∼69% of total sample) with complete data born without congenital anomalies in the years 1996-2011 in Brazil, Argentina, Chile, Venezuela, Ecuador, Colombia, Bolivia, and Uruguay. Prenatal care visits were significantly (at p<.05) and positively associated with BW and negatively associated with LBW for all countries. The OLS coefficients ranged from 9 grams per visit in Bolivia to 36 grams in Uruguay. The association with LBW was strongest for Chile (OR = 0.87 per visit) and lowest for Argentina and Venezuela (OR = 0.95). The association decreased in the recent decade compared to earlier years. Our findings suggest that estimates of association between prenatal care and fetal growth are population-specific and may not be generalizable to other populations. Furthermore, as one of the indicators for a country's healthcare system for maternal and child health, prenatal care is a highly variable indicator between countries in South America. PMID:24625630

  18. The vague volcano-seismic clock of the South American Pacific margin

    NASA Astrophysics Data System (ADS)

    Scalera, G.

    2013-08-01

    During his trip on the Beagle, Charles Darwin wrote about the eruptions associated with the Concepción earthquake of 1835. A later survey by Lorenzo Casertano, following the great 1960 Chilean earthquake, identified some unclear evidence of a link between eruptions and the seismic event, although some reservations were also raised. Using data available in 2006 in the Smithsonian Institution Catalogue of volcanic eruptions, Scalera revealed grounded evidence that South-American Wadati-Benioff zone earthquakes of magnitudes greater than 8.4 are associated with an increased rate of volcanic eruptions, but it was still impossible to determine a causal link between the two phenomena. An average return period of about 50 yr was deducible from the data for the time window 1800-1999. After 2006, the Smithsonian Institution's effort to improve our knowledge of this region has greatly increased the completeness of the catalogue, adding the eruptions from the 2000-2010 interval, together with 50 % more new entries in the list of Andean volcanoes. The great Chilean Maule earthquake of 27 February 2010 (M=8.8), occurring exactly five decades after the 1960 event, provided an occasion to reanalyse this updated database. The results suggest a preferential causal eruptions-earthquake relationship, but additional future volcano-seismic events should be studied to arrive at a definitive conclusion, within the perspective of using this phenomenon for Civil Protection. The possible correlation of South American volcano-seismic events with the Markowitz oscillation of the Polar Motion is another good reason for trying to establish an integrated geodynamic explanation.

  19. Anthropogenic Effects on Total Water Storage from GRACE on Large South American Watersheds

    NASA Astrophysics Data System (ADS)

    Xavier, L.; Becker, M.; Cazenave, A. A.; Güntner, A.; Rotunno, O.

    2009-12-01

    Over continents, GRACE total water storage (TWS) solutions are expected to represent main surface, soil and groundwater stocks variability. Recent studies have showed that intensive groundwater resources withdrawal in India can be “captured” by GRACE. Another important anthropogenic impact on the natural water cycle is the building and operation of large dams. Even though they impact primarily the local water stock variations, one can expect subsequent changes on the water cycle and some evidence of this from GRACE. This would be particularly evident where the volume of stored water behind dams represents a significant proportion of the total TWS. In this study, we analyzed the effect on the water cycle of large dams over South American large watersheds. Most of Brazilians large dams are located in the Upper Paraná watershed, upstream the Itaipu dam. By performing a correlation analysis between the upstream integrated rainfall and the GRACE TWS series, we found a noticeable phase difference between the two quantities. The phase difference is larger over the utmost upstream region of Upper Parana watershed. We assumed that this pattern could be due to an effect of man-made reservoirs. We took into account the reservoirs storage and found that they induce an additional phase-lag of about 1 month in the TWS response to precipitation forcing. We also investigated dams’ impact on the simulations of the Water Gap Hydrological Model. The results also show a similar time delay similar, suggesting that the model correctly accounts for the dam effect. Finally we see similar lags, though smaller, over other South American river basins.

  20. Prevalence and genetic diversity of haematozoa in South American waterfowl and evidence for intercontinental redistribution of parasites by migratory birds

    PubMed Central

    Smith, Matthew M.; Ramey, Andrew M.

    2015-01-01

    To understand the role of migratory birds in the movement and transmission of haematozoa within and between continental regions, we examined 804 blood samples collected from eleven endemic species of South American waterfowl in Peru and Argentina for infection by Haemoproteus, Plasmodium, and/or Leucocytozoon blood parasites. Infections were detected in 25 individuals of six species for an overall apparent prevalence rate of 3.1%. Analysis of haematozoa mitochondrial DNA revealed twelve distinct parasite haplotypes infecting South American waterfowl, four of which were identical to lineages previously observed infecting ducks and swans sampled in North America. Analysis of parasite mitochondrial DNA sequences revealed close phylogenetic relationships between lineages originating from waterfowl samples regardless of continental affiliation. In contrast, more distant phylogenetic relationships were observed between parasite lineages from waterfowl and passerines sampled in South America for Haemoproteus and Leucocytozoon, suggesting some level of host specificity for parasites of these genera. The detection of identical parasite lineages in endemic, South American waterfowl and North American ducks and swans, paired with the close phylogenetic relationships of haematozoa infecting waterfowl on both continents, provides evidence for parasite redistribution between these regions by migratory birds. PMID:25830104

  1. Strategies to Improve Teacher Retention in American Overseas Schools in the Near East South Asia Region: A Qualitative Analysis

    ERIC Educational Resources Information Center

    Mancuso, Steven V.; Roberts, Laura; White, George P.; Yoshida, Roland K.; Weston, David

    2011-01-01

    Using a qualitative analysis and drawing from sociological theory, this study examined reasons for teacher turnover and retention from a representative sample of 248 teachers in American overseas schools in the Near East South Asia region. Results suggested that the most important reasons to stay or move pertained to supportive leadership,…

  2. 76 FR 18419 - Movement of Hass Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-04

    ... (74 FR 651-664, Docket No. APHIS-2008- 0126), that led to establishment of the Peruvian Hass avocado... effective on January 4, 2010 (75 FR 1-13), we stated that more research would need to be done in accordance... Movement of Hass Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist...

  3. 76 FR 26654 - Movement of Hass Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-09

    ..., 2011, we published in the Federal Register (76 FR 18419-18421, Docket No. APHIS-2010-0127) a proposal... Avocados From Areas Where Mediterranean Fruit Fly or South American Fruit Fly Exist AGENCY: Animal and... from Mediterranean fruit fly quarantined areas in the United States with a certificate if the fruit...

  4. Return Migrations of African-Americans to the South: Reclaiming a Land of Promise, Going Home, or Both?

    ERIC Educational Resources Information Center

    Falk, William F.; Hunt, Larry L.; Hunt, Matthew O.

    2004-01-01

    Using samples of census data from the university of Minnesota Population Center's "Integrated Public Use Microdata Series" (IPUMS), we describe trends in African-American migration to the South across recent decades, and explore the applicability of the concept of "return migration" to various demographic patterns. Our findings suggest that the…

  5. "Getting High and Getting By": Dimensions of Drug Selling Behaviors among American Mexican Gang Members in South Texas

    ERIC Educational Resources Information Center

    Valdez, Avelardo; Sifaneck, Stephen J.

    2004-01-01

    This article discerns the role that Mexican American gang members play in drug markets, and the relationship between gang members' drug use and drug selling in South Texas. A four-part typology based on the two dimensions of gang type and gang member emerged from this qualitative analysis of 160 male gang members: Homeboys, Hustlers, Slangers, and…

  6. "No Unfavorable Comments from Any Quarter": Teaching Black History to White Students in the American South, 1928-1943

    ERIC Educational Resources Information Center

    Woyshner, Christine

    2012-01-01

    Background/Context: The history curriculum is often used to help reach the goal of racial tolerance and understanding by teaching about the nation's diversity. Many educators believe that teaching about diverse peoples in schools will bring about greater equity in society. This historical study looks at the segregated American South from 1928 to…

  7. Postmortem findings in four south American sea lions (Otaria byronia) from an urban colony in Valdivia, Chile.

    PubMed

    Sepúlveda, Maximiliano A; Seguel, Mauricio; Alvarado-Rybak, Mario; Verdugo, Claudio; Muñoz-Zanzi, Claudia; Tamayo, Rafael

    2015-01-01

    We performed postmortem examination on four South American sea lions (Otaria byronia) from an urban colony in Valdivia, Chile. Chronic leptospirosis and suspected morbillivirus-like infection were diagnosed in one individual. Antibodies against Toxoplasma gondii and the zoonotic helminthes Contracaecum sp., Pseudoterranova sp., and Diphyllobothrium sp. were also detected. PMID:25380367

  8. Morphology of the lingual surface of South American fur seal (Arctocephalus australis) and sea lion (Otaria flavescens).

    PubMed

    Erdoğan, Serkan; Villar Arias, Silvia; Pérez, William

    2015-02-01

    In this study, we aimed to describe the morphological characteristics of the lingual papillae in two species of Otariidae family by stereomicroscopy and scanning electron microscopy. We used tongues of two South American Otariidae species. The tongues were elongated and terminated in bifid apex and there was no median sulcus on the dorsal lingual surface. The most numerous type of lingual papilla was filiform in the South American fur seal (SASL) and entire dorsal lingual surface was covered by these filiform papillae but the dorsal surface of the tongue of the South American sea lion was covered by numerous polygonal projections, which were different in size. Fungiform papillae were detected in only SASL and they randomly distributed on the lingual apex and body, and some fungiform papillae were collected into twosome or threesome groups on the posterior part of the lingual body. Circumvallate papilla was found in the center of the lingual radix of South American sea lion. Thread-like conical papillae were common for both species and they located on the lingual radix. We determined that lingual surface morphology was completely different in each species, although they were members of the same family, Otariidae. PMID:25431362

  9. Native American Student Perceptions of the Cultural Environment and Factors for Academic Success at the University of South Dakota

    ERIC Educational Resources Information Center

    Grignon, Charles M.

    2009-01-01

    Considering the high retention rates for Native American students in 2009 and 2008 in the two semesters at the University of South Dakota, there is a need to know the Native student perceptions of factors for their academic success. Native professors and administrators would benefit to know this information to continue to make improvements in…

  10. Perfluorinated Alkyl Acids in Plasma of American Alligators (Alligator Mississippiensis) from Florida and South Carolina

    NASA Technical Reports Server (NTRS)

    Bangma, Jacqueline T.; Bowden, John A.; Brunell, Arnold M.; Christie, Ian; Finnell, Brendan; Guillette, Matthew P.; Jones, Martin; Lowers, Russell H.; Rainwater, Thomas R.; Reiner, Jessica L.; Wilkinson, Philip M.; Guillette, Louis J., Jr.

    2016-01-01

    This study aimed to quantitate fourteen perfluoroalkyl acids (PFAAs) in 125 adult American alligators at twelve sites across the southeastern US. Of those fourteen PFAAs, nine were detected in 65% - 100% of the samples: PFOA, PFNA, PFDA, PFUnA, PFDoA, PFTriA, PFTA, PFHxS, and PFOS. Males (across all sites) showed significantly higher concentrations of four PFAAs: PFOS (p = 0.01), PFDA (p = 0.0003), PFUnA (p = 0.021), and PFTriA (p = 0.021). Concentrations of PFOS, PFHxS, and PFDA in plasma were significantly different among the sites in each sex. Alligators at Merritt Island National Wildlife Refuge and Kiawah Nature Conservancy both exhibited some of the highest PFOS concentrations (medians 99.5 ng/g and 55.8 ng/g respectively) in plasma measured to date in a crocodilian species. A number of positive correlations between PFAAs and snout-vent length (SVL) were observed in both sexes suggesting PFAA body burdens increase with increasing size. In addition, several significant correlations among PFAAs in alligator plasma may suggest conserved sources of PFAAs at each site throughout the greater study area. This study is the first to report PFAAs in American alligators, reveals potential PFAA hot spots in Florida and South Carolina, and provides and additional contaminant of concern when assessing anthropogenic impacts on ecosystem health.

  11. Seismic hazard of American Samoa and neighboring South Pacific Islands--methods, data, parameters, and results

    USGS Publications Warehouse

    Petersen, Mark D.; Harmsen, Stephen C.; Rukstales, Kenneth S.; Mueller, Charles S.; McNamara, Daniel E.; Luco, Nicolas; Walling, Melanie

    2012-01-01

    American Samoa and the neighboring islands of the South Pacific lie near active tectonic-plate boundaries that host many large earthquakes which can result in strong earthquake shaking and tsunamis. To mitigate earthquake risks from future ground shaking, the Federal Emergency Management Agency requested that the U.S. Geological Survey prepare seismic hazard maps that can be applied in building-design criteria. This Open-File Report describes the data, methods, and parameters used to calculate the seismic shaking hazard as well as the output hazard maps, curves, and deaggregation (disaggregation) information needed for building design. Spectral acceleration hazard for 1 Hertz having a 2-percent probability of exceedance on a firm rock site condition (Vs30=760 meters per second) is 0.12 acceleration of gravity (1 second, 1 Hertz) and 0.32 acceleration of gravity (0.2 seconds, 5 Hertz) on American Samoa, 0.72 acceleration of gravity (1 Hertz) and 2.54 acceleration of gravity (5 Hertz) on Tonga, 0.15 acceleration of gravity (1 Hertz) and 0.55 acceleration of gravity (5 Hertz) on Fiji, and 0.89 acceleration of gravity (1 Hertz) and 2.77 acceleration of gravity (5 Hertz) on the Vanuatu Islands.

  12. Glyphosate-resistant weeds of South American cropping systems: an overview.

    PubMed

    Vila-Aiub, Martin M; Vidal, Ribas A; Balbi, Maria C; Gundel, Pedro E; Trucco, Frederico; Ghersa, Claudio M

    2008-04-01

    Herbicide resistance is an evolutionary event resulting from intense herbicide selection over genetically diverse weed populations. In South America, orchard, cereal and legume cropping systems show a strong dependence on glyphosate to control weeds. The goal of this report is to review the current knowledge on cases of evolved glyphosate-resistant weeds in South American agriculture. The first reports of glyphosate resistance include populations of highly diverse taxa (Lolium multiflorum Lam., Conyza bonariensis L., C. canadensis L.). In all instances, resistance evolution followed intense glyphosate use in fruit fields of Chile and Brazil. In fruit orchards from Colombia, Parthenium hysterophorus L. has shown the ability to withstand high glyphosate rates. The recent appearance of glyphosate-resistant Sorghum halepense L. and Euphorbia heterophylla L. in glyphosate-resistant soybean fields of Argentina and Brazil, respectively, is of major concern. The evolution of glyphosate resistance has clearly taken place in those agroecosystems where glyphosate exerts a strong and continuous selection pressure on weeds. The massive adoption of no-till practices together with the utilization of glyphosate-resistant soybean crops are factors encouraging increase in glyphosate use. This phenomenon has been more evident in Argentina and Brazil. The exclusive reliance on glyphosate as the main tool for weed management results in agroecosystems biologically more prone to glyphosate resistance evolution. PMID:18161884

  13. Multidecadal variability of moisture and heat budgets of the South American monsoon system

    NASA Astrophysics Data System (ADS)

    Garcia, Sâmia R.; Kayano, Mary T.

    2015-08-01

    The variability of sources or sinks of moisture and heat for the South American monsoon system (SAMS) region is investigated for the 1958-1995 period. So, moisture and heat budget equations are applied to data from the National Centers for Environmental Prediction (NCEP) reanalysis project. Sources or sinks of moisture and heat are the equation residues and are referred to as residue and diabatic terms, respectively. Using empirical orthogonal function (EOF) analysis, the dominant variability modes of these terms are obtained for the study period, with the monthly anomalies of the residue and diabatic terms employed. For residue EOF01, negative (positive) principal component (PC01) values correspond to positive (negative) residue anomalies over tropical South America (TSAM), which indicate a moisture source (sink) before (after) 1976, cold (warm) phase of the Pacific Decadal Oscillation (PDO). For the EOF01 of the diabatic term, negative (positive) PC01 values correspond to negative (positive) diabatic anomalies over TSAM, indicating a heat sink (source) before (after) 1976. Thus, a moisture source (sink) and a heat sink (source) occur over TSAM before (after) 1976. These findings are corroborated by composite analysis of the anomalies of precipitable water, 850 hPa air temperature, 500 hPa vertical pressure velocity, vertically integrated moisture flux (VIMF), VIMF divergence, and precipitation. In terms of system thermodynamics, these composites are indicative of SAMS weakening (strengthening) before (after) 1976, cold (warm) PDO phase.

  14. Metagenomic Survey of Viral Diversity Obtained from Feces of Subantarctic and South American Fur Seals.

    PubMed

    Kluge, Mariana; Campos, Fabrício Souza; Tavares, Maurício; de Amorim, Derek Blaese; Valdez, Fernanda Pedone; Giongo, Adriana; Roehe, Paulo Michel; Franco, Ana Claudia

    2016-01-01

    The Brazilian South coast seasonally hosts numerous marine species, observed particularly during winter months. Some animals, including fur seals, are found dead or debilitated along the shore and may harbor potential pathogens within their microbiota. In the present study, a metagenomic approach was performed to evaluate the viral diversity in feces of fur seals found deceased along the coast of the state of Rio Grande do Sul. The fecal virome of two fur seal species was characterized: the South American fur seal (Arctocephalus australis) and the Subantarctic fur seal (Arctocephalus tropicalis). Fecal samples from 10 specimens (A. australis, n = 5; A. tropicalis, n = 5) were collected and viral particles were purified, extracted and amplified with a random PCR. The products were sequenced through Ion Torrent and Illumina platforms and assembled reads were submitted to BLASTx searches. Both viromes were dominated by bacteriophages and included a number of potentially novel virus genomes. Sequences of picobirnaviruses, picornaviruses and a hepevirus-like were identified in A. australis. A rotavirus related to group C, a novel member of the Sakobuvirus and a sapovirus very similar to California sea lion sapovirus 1 were found in A. tropicalis. Additionally, sequences of members of the Anelloviridae and Parvoviridae families were detected in both fur seal species. This is the first metagenomic study to screen the fecal virome of fur seals, contributing to a better understanding of the complexity of the viral community present in the intestinal microbiota of these animals. PMID:26986573

  15. Metagenomic Survey of Viral Diversity Obtained from Feces of Subantarctic and South American Fur Seals

    PubMed Central

    Kluge, Mariana; Campos, Fabrício Souza; Tavares, Maurício; de Amorim, Derek Blaese; Valdez, Fernanda Pedone; Giongo, Adriana; Roehe, Paulo Michel; Franco, Ana Claudia

    2016-01-01

    The Brazilian South coast seasonally hosts numerous marine species, observed particularly during winter months. Some animals, including fur seals, are found dead or debilitated along the shore and may harbor potential pathogens within their microbiota. In the present study, a metagenomic approach was performed to evaluate the viral diversity in feces of fur seals found deceased along the coast of the state of Rio Grande do Sul. The fecal virome of two fur seal species was characterized: the South American fur seal (Arctocephalus australis) and the Subantarctic fur seal (Arctocephalus tropicalis). Fecal samples from 10 specimens (A. australis, n = 5; A. tropicalis, n = 5) were collected and viral particles were purified, extracted and amplified with a random PCR. The products were sequenced through Ion Torrent and Illumina platforms and assembled reads were submitted to BLASTx searches. Both viromes were dominated by bacteriophages and included a number of potentially novel virus genomes. Sequences of picobirnaviruses, picornaviruses and a hepevirus-like were identified in A. australis. A rotavirus related to group C, a novel member of the Sakobuvirus and a sapovirus very similar to California sea lion sapovirus 1 were found in A. tropicalis. Additionally, sequences of members of the Anelloviridae and Parvoviridae families were detected in both fur seal species. This is the first metagenomic study to screen the fecal virome of fur seals, contributing to a better understanding of the complexity of the viral community present in the intestinal microbiota of these animals. PMID:26986573

  16. The diversification of eastern South American open vegetation biomes: Historical biogeography and perspectives

    NASA Astrophysics Data System (ADS)

    Werneck, Fernanda P.

    2011-06-01

    The eastern-central South American open vegetation biomes occur across an extensive range of environmental conditions and are organized diagonally including three complexly interacting tropical/sub-tropical biomes. Seasonally Dry Tropical Forests (SDTFs), Cerrado, and Chaco biomes are seasonally stressed by drought, characterized by significant plant and animal endemism, high levels of diversity, and highly endangered. However, these open biomes have been overlooked in biogeographic studies and conservation projects in South America, especially regarding fauna studies. Here I compile and evaluate the biogeographic hypotheses previously proposed for the diversification of these three major open biomes, specifically their distributions located eastern and southern of Andes. My goal is to generate predictions and provide a background for testable hypotheses. I begin by investigating both continental (inter-biome) and regional (within-biome) levels, and I then provide a biogeographical summary for these regions. I also suggest how novel molecular-based historical biogeographic/phylogeographic approaches could contribute to the resolution of long-standing questions, identify potential target fauna groups for development of these lines of study, and describe fertile future research agendas.

  17. Testing Bergmann's rule and the Rosenzweig hypothesis with craniometric studies of the South American sea lion.

    PubMed

    Sepúlveda, Maritza; Oliva, Doris; Duran, L René; Urra, Alejandra; Pedraza, Susana N; Majluf, Patrícia; Goodall, Natalie; Crespo, Enrique A

    2013-04-01

    We tested the validity of Bergmann's rule and Rosenzweig's hypothesis through an analysis of the geographical variation of the skull size of Otaria flavescens along the entire distribution range of the species (except Brazil). We quantified the sizes of 606 adult South American sea lion skulls measured in seven localities of Peru, Chile, Uruguay, Argentina, and the Falkland/Malvinas Islands. Geographical and environmental variables included latitude, longitude, and monthly minimum, maximum, and mean air and ocean temperatures. We also included information on fish landings as a proxy for productivity. Males showed a positive relationship between condylobasal length (CBL) and latitude, and between CBL and the six temperature variables. By contrast, females showed a negative relationship between CBL and the same variables. Finally, female skull size showed a significant and positive correlation with fish landings, while males did not show any relationship with this variable. The body size of males conformed to Bergmann's rule, with larger individuals found in southern localities of South America. Females followed the converse of Bergmann's rule at the intraspecific level, but showed a positive relationship with the proxy for productivity, thus supporting Rosenzweig's hypothesis. Differences in the factors that drive body size in females and males may be explained by their different life-history strategies. Our analyses demonstrate that latitude and temperature are not the only factors that explain spatial variation in body size: others such as food availability are also important for explaining the ecogeographical patterns found in O. flavescens. PMID:23053224

  18. Eliminating Malaria in the American South: An Analysis of the Decline of Malaria in 1930s Alabama

    PubMed Central

    Mohler, George

    2013-01-01

    Until the 1930s, malaria was endemic throughout large swaths of the American South. We used a Poisson mixture model to analyze the decline of malaria at the county level in Alabama (an archetypical Deep South cotton state) during the 1930s. Employing a novel data set, we argue that, contrary to a leading theory, the decline of malaria in the American South was not caused by population movement away from malarial areas or the decline of Southern tenant farming. We elaborate and provide evidence for an alternate explanation that emphasizes the role of targeted New Deal–era public health interventions and the development of local-level public health infrastructure. We show that, rather than disappearing as a consequence of social change or economic improvements, malaria was eliminated in the Southern United States in the face of economic dislocation and widespread and deep-seated poverty. PMID:23763415

  19. Parental attendance and brood success in American Oystercatchers in South Carolina

    USGS Publications Warehouse

    Thibault, Janet M.; Sanders, Felicia J.; Jodice, Patrick G.

    2010-01-01

    Research on breeding American Oystercatchers has focused on identifying factors that affect reproductive success but little attention has been paid to parent behavior during chick-rearing. Parental attendance of American Oystercatchers was measured in Bulls Bay and along the Atlantic Intracoastal Waterway (Waterway) within the Cape Romain Region, South Carolina, USA, during 2006. Parental attendance rates averaged 90.9% in Bulls Bay and 81.4% along the Waterway. Daily survival of chicks was higher in Bulls Bay (0.989 ± 0.007) compared to the Waterway (0.966 ± 0.012). The extent of shellfish reefs (i.e. foraging areas) adjacent to nest sites was greater in Bulls Bay (5,633 ± 658 m2) compared to the Waterway (3,273 ± 850 m2). Mean parental attendance in Bulls Bay was higher for successful broods (90.5%) compared to failed broods (79.8%). In contrast, mean parental attendance along the Waterway was higher for failed broods (93.4%) compared to successful broods (67.5%). Less extensive shellfish reefs adjacent to nest sites along the Waterway appeared to require parents to depart more frequently to forage and the resultant reduction in attendance may have negatively affected chick survival. Bulls Bay may provide higher quality nesting habitat compared to the Waterway with respect to proximity to food resources and parental attendance. Management and conservation efforts for American Oystercatchers should consider the relationship between foraging and nesting habitat and variability in behavioral attributes, such as parental attendance, in relationship to environmental conditions which ultimately affect reproductive success.

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  1. Patterns of Species Richness and Turnover for the South American Rodent Fauna

    PubMed Central

    Maestri, Renan; Patterson, Bruce D.

    2016-01-01

    Understanding the spatial distribution of species sheds light on the group’s biogeographical history, offers clues to the drivers of diversity, and helps to guide conservation strategies. Here, we compile geographic range information for South America’s diverse rodents, whose 14 families comprise ~50% of the continent’s mammalian species. The South American rodent fauna is dominated by independent and temporally staggered radiations of caviomorph and sigmodontine groups. We mapped species richness and turnover of all rodents and the principal clades to identify the main predictors of diversity patterns. Species richness was highest in the Andes, with a secondary hotspot in Atlantic Forest and some regions of considerable richness in Amazonia. Differences in richness were evident between the caviomorphs and sigmodontines, the former showing the greatest richness in tropical forests whereas the latter show—and largely determine—the all-rodent pattern. Elevation was the main predictor of sigmodontine richness, whereas temperature was the principal variable correlated with richness of caviomorphs. Across clades, species turnover was highest along the Andes and was best explained by elevational relief. In South America, the effects of the familiar latitudinal gradient in species richness are mixed with a strong longitudinal effect, triggered by the importance of elevation and the position of the Andes. Both latitudinal and elevational effects help explain the complicated distribution of rodent diversity across the continent. The continent’s restricted-range species—those seemingly most vulnerable to localized disturbance—are mostly distributed along the Andes and in Atlantic Forest, with the greatest concentration in Ecuador. Both the Andes and Atlantic Forest are known hotspots for other faunal and floral components. Contrasting patterns of the older caviomorph and younger sigmodontine radiations underscore the interplay of both historical and

  2. Seasonal precipitation patterns along pathways of South American low-level jets and aerial rivers

    NASA Astrophysics Data System (ADS)

    Poveda, Germán.; Jaramillo, Liliana; Vallejo, Luisa F.

    2014-01-01

    We study the seasonal dynamics of the eastern Pacific (CHOCO) and Caribbean low-level jets (LLJ), and aerial rivers (AR) acting on tropical and subtropical South America. Using the ERA-Interim reanalysis (1979-2012), we show that the convergence of both LLJs over the eastern Pacific-western Colombia contributes to the explanation of the region's world-record rainfall. Diverse variables involved in the transport and storage of moisture permit the identification of an AR over northern South America involving a midtropospheric easterly jet that connects the Atlantic and Pacific Oceans across the Andes, with stronger activity in April to August. Other major seasonal AR pathways constitute part of a large gyre originating over the tropical North Atlantic, veering to the southeast over the eastern Andes and reaching regions of northern Argentina and southeastern Brazil. We illustrate the distribution of average seasonal precipitation along the LLJs and AR pathways with data from the Tropical Rainfall Measuring Mission (1998-2011), combined with considerations of CAPE, topography, and land cover. In addition, the theory of the biotic pump of atmospheric moisture (BiPAM) is tested at seasonal time scales, and found to hold in 8 out of 12 ARs, and 22 out of 32 forest-covered tracks (64% in distance) along the ARs. Deviations from BiPAM's predictions of rainfall distribution are explained by the effects of topography, orography, and land cover types different from forests. Our results lend a strong observational support to the BiPAM theory at seasonal time scales over South American forested flat lands.

  3. Vertical variations in the influence of the amount effect: South American Summer Monsoon Region

    NASA Astrophysics Data System (ADS)

    Samuels-Crow, K. E.; Galewsky, J.; Worden, J. R.

    2014-12-01

    Recent theoretical studies have shown that convective recycling of atmospheric water vapor gives rise to the isotope "amount effect" in which d values are lower than predicted by simple Rayleigh distillation processes (i.e. (DdD = dDvapor ­- dDRayleigh < 0‰). Several studies have linked isotopes in precipitation [e.g. Vimeux et al., 2009] and atmospheric water vapor [e.g. Samuels-Crow et al., 2014] in the tropical Andes to upwind convection associated with the South American Summer Monsoon (SASM). The vertical structure of this convective influence, however, remains unknown. Understanding the vertical structure of the amount effect over South America is essential for improving theoretical constraints and developing better models of the influence of the SASM on southern hemisphere humidity. Additionally, evaluating the vertical and lateral extent of the SASM's convective influence can provide important constraints for interpreting paleoclimate proxies in the region. We use data from the Tropospheric Emission Spectrometer (TES) to examine the vertical structure of the amount effect associated with the SASM and relate these results to regional convective precipitation and local subcloud equivalent potential temperature. Preliminary results show that DdD is below 0‰ from the boundary layer through the mid-troposphere over tropical South America during austral summer, and meridional averages show that convective precipitation is highest over these areas where DdD < 0‰ extends higher in the atmosphere. We hypothesize that the depth of convection in the monsoon region controls the vertical structure of DdD, which should also be coherently linked to local equivalent potential temperature. References Vimeux et al. (2009), Palaeogeogr Palaeocl, 281(3-4), 229-241, doi:10.1016/j.palaeo.2008.03.054. Samuels-Crow et al. (2014), J Geophys Res-Atmos, doi:10.1002/(ISSN)2169-8996.

  4. Short-Term Dynamic and Local Epidemiological Trends in the South American HIV-1B Epidemic

    PubMed Central

    Junqueira, Dennis Maletich; de Medeiros, Rubia Marília; Gräf, Tiago; Almeida, Sabrina Esteves de Matos

    2016-01-01

    The human displacement and sexual behavior are the main factors driving the HIV-1 pandemic to the current profile. The intrinsic structure of the HIV transmission among different individuals has valuable importance for the understanding of the epidemic and for the public health response. The aim of this study was to characterize the HIV-1 subtype B (HIV-1B) epidemic in South America through the identification of transmission links and infer trends about geographical patterns and median time of transmission between individuals. Sequences of the protease and reverse transcriptase coding regions from 4,810 individuals were selected from GenBank. Maximum likelihood phylogenies were inferred and submitted to ClusterPicker to identify transmission links. Bayesian analyses were applied only for clusters including ≥5 dated samples in order to estimate the median maximum inter-transmission interval. This study analyzed sequences sampled from 12 South American countries, from individuals of different exposure categories, under different antiretroviral profiles, and from a wide period of time (1989–2013). Continentally, Brazil, Argentina and Venezuela were revealed important sites for the spread of HIV-1B among countries inside South America. Of note, from all the clusters identified about 70% of the HIV-1B infections are primarily occurring among individuals living in the same geographic region. In addition, these transmissions seem to occur early after the infection of an individual, taking in average 2.39 years (95% CI 1.48–3.30) to succeed. Homosexual/Bisexual individuals transmit the virus as quickly as almost half time of that estimated for the general population sampled here. Public health services can be broadly benefitted from this kind of information whether to focus on specific programs of response to the epidemic whether as guiding of prevention campaigns to specific risk groups. PMID:27258369

  5. Short-Term Dynamic and Local Epidemiological Trends in the South American HIV-1B Epidemic.

    PubMed

    Junqueira, Dennis Maletich; de Medeiros, Rubia Marília; Gräf, Tiago; Almeida, Sabrina Esteves de Matos

    2016-01-01

    The human displacement and sexual behavior are the main factors driving the HIV-1 pandemic to the current profile. The intrinsic structure of the HIV transmission among different individuals has valuable importance for the understanding of the epidemic and for the public health response. The aim of this study was to characterize the HIV-1 subtype B (HIV-1B) epidemic in South America through the identification of transmission links and infer trends about geographical patterns and median time of transmission between individuals. Sequences of the protease and reverse transcriptase coding regions from 4,810 individuals were selected from GenBank. Maximum likelihood phylogenies were inferred and submitted to ClusterPicker to identify transmission links. Bayesian analyses were applied only for clusters including ≥5 dated samples in order to estimate the median maximum inter-transmission interval. This study analyzed sequences sampled from 12 South American countries, from individuals of different exposure categories, under different antiretroviral profiles, and from a wide period of time (1989-2013). Continentally, Brazil, Argentina and Venezuela were revealed important sites for the spread of HIV-1B among countries inside South America. Of note, from all the clusters identified about 70% of the HIV-1B infections are primarily occurring among individuals living in the same geographic region. In addition, these transmissions seem to occur early after the infection of an individual, taking in average 2.39 years (95% CI 1.48-3.30) to succeed. Homosexual/Bisexual individuals transmit the virus as quickly as almost half time of that estimated for the general population sampled here. Public health services can be broadly benefitted from this kind of information whether to focus on specific programs of response to the epidemic whether as guiding of prevention campaigns to specific risk groups. PMID:27258369

  6. Patterns of Species Richness and Turnover for the South American Rodent Fauna.

    PubMed

    Maestri, Renan; Patterson, Bruce D

    2016-01-01

    Understanding the spatial distribution of species sheds light on the group's biogeographical history, offers clues to the drivers of diversity, and helps to guide conservation strategies. Here, we compile geographic range information for South America's diverse rodents, whose 14 families comprise ~50% of the continent's mammalian species. The South American rodent fauna is dominated by independent and temporally staggered radiations of caviomorph and sigmodontine groups. We mapped species richness and turnover of all rodents and the principal clades to identify the main predictors of diversity patterns. Species richness was highest in the Andes, with a secondary hotspot in Atlantic Forest and some regions of considerable richness in Amazonia. Differences in richness were evident between the caviomorphs and sigmodontines, the former showing the greatest richness in tropical forests whereas the latter show-and largely determine-the all-rodent pattern. Elevation was the main predictor of sigmodontine richness, whereas temperature was the principal variable correlated with richness of caviomorphs. Across clades, species turnover was highest along the Andes and was best explained by elevational relief. In South America, the effects of the familiar latitudinal gradient in species richness are mixed with a strong longitudinal effect, triggered by the importance of elevation and the position of the Andes. Both latitudinal and elevational effects help explain the complicated distribution of rodent diversity across the continent. The continent's restricted-range species-those seemingly most vulnerable to localized disturbance-are mostly distributed along the Andes and in Atlantic Forest, with the greatest concentration in Ecuador. Both the Andes and Atlantic Forest are known hotspots for other faunal and floral components. Contrasting patterns of the older caviomorph and younger sigmodontine radiations underscore the interplay of both historical and ecological factors in

  7. Impacts of ENSO on the South American Summer Monsoon During 1997-1999

    NASA Technical Reports Server (NTRS)

    Lau, K.-M.; Zhou, Jia-Yu; Einaudi, Franco (Technical Monitor)

    2001-01-01

    Using the National Center for Environmental Prediction (NCEP) Reanalysis, and CPC Merged Analysis Product (CMAP) rainfall, we have compared and contrasted the anomalies of the South American Summer Monsoon (SASM) during two extreme years of 1997/98 (EI Nino) and 1998/99 (La Nina). The results are assessed against a "canonical" ENSO response (CER) pattern for the SASM obtained from empirical mode decomposition based on a previous period (1980-1995). Overall, the SASM anomalies compare well with CER, but with some important differences. Anomalies occurring in the warm phase of the 1997-98 El Nino are very significant and robust, while those occurring in 1998/99 La Nina, appear to be reversed from 1997/98, but are relatively weak and less well-defined. The most pronounced signal in DJF 1997/98 is the development of drought conditions in northern Brazil, excessive rainfall over northern Peru and Ecuador, and over Uruguay and southern Brazil. The tropical rainfall anomalies are associated with the eastward shift of the Walker circulation, which is represented by pronounced low-level anomalous westerlies over the equatorial eastern Pacific and easterlies over northern Brazil. The easterlies are deflected sharply southeastward by the steep topography of the Andes, enhancing the low-level jet (LLJ) along the eastern foothills of the Andes near 15-20 S. The LLJ penetrates deep into the extratropics, yielding rainfall anomalies further poleward compared to CER. During DJF 1997/98, the eastward expansion of the warm tropospheric temperature over the Nino-3 region causes anomalous geopotential height to develop in the upper troposphere above the Altiplano, leading to a strengthened Bolivian High. An upper-tropospheric jet anomaly maximum is found over the subtropical continent near 30 S, due to increasing meridional gradient of tropospheric temperature, as well as teleconnection patterns linking the South Pacific and the South Atlantic. Consistent with the CER, the South

  8. Comparative analysis of the Late Cretaceous to Recent post-breakup basin evolution of the South-American and South-African margin of the southern Atlantic

    NASA Astrophysics Data System (ADS)

    Kukla, Peter; Back, Stefan

    2010-05-01

    Recently, considerable attempts have been made to compare the sedimentary basin evolution and the associated tectonic framework on both sides of the South-Atlantic (e.g. Mohriak et al., 2008, and references therein). Yet there are still unresolved questions. Amongst the most striking observations is that multiple phases of volcanism, uplift and subsidence are recorded after the break-up of the southern South Atlantic margin segment on both sides of the Florianopolis - Walvis Ridge volcanic complex, features that are regarded as atypical when compared to published examples of other post-breakup continental margin successions. However, the tectono-sedimentary and magmatic styles markedly differ from south to north across the volcanic complex. In seismic reflection data, voluminous extrusives are manifested by the occurrence of large wedges of seaward dipping reflector sequences south of the volcanic complex, whilst large volumes of Cretaceous mafic alkaline rocks only occur north of the Florianopolis - Walvis Ridge complex. It can be expected that these differences are of a broad importance for the understanding of both break-up and post-breakup processes. This presentation focuses on a comparison of the post-breakup stratigraphic development of the South American and South African continental margins that both record thick post-rift sedimentary successions. Basins along the southern African margin are much narrower in comparison to their South American counterparts, constituting a pronounced margin asymmetry across the Atlantic. Adding to the heterogeneity of the system, the northernmost segment of the South Atlantic rift and salt basins is also characterized by a pronounced asymmetry, with the Brazilian margin now comprising narrower and deeper rift basins with less salt than the Congo-Gabon conjugate margin. In general, it seems that in the salt-prone areas both offshore South America and southern Africa, salt-related tectonics are amongst the key parameters

  9. The irrational beliefs inventory: cross-cultural comparisons between South African and previously published Dutch and American samples.

    PubMed

    du Plessis, Marilize; Möller, André T; Steel, Henry R

    2004-12-01

    The Irrational Beliefs Inventory gives a measure of irrational beliefs, as postulated by Ellis's Rational Emotive Behavior therapy. Given the increasing cross-cultural use of psychometric scales, it is important to assess whether the psychometric properties of the inventory are consistent across cultures. In the present study cross-cultural applicability, in terms of internal consistency and independence of subscales, was investigated for an ad hoc sample of White (n= 100, M age = 21.3 yr., SD=4.0) and Black (n=82, M age=19.8 yr., SD=2.2) undergraduate South African university students. Cronbach coefficients alpha for the subscales and Pearson correlations between subscales for American and Dutch students, as reported by Bridges and Sanderman, were compared with those indices for the South African students. The magnitude and rank order of Cronbach alpha, as well as the correlations between subscales for the three groups showed strong similarities. Values of alpha for the Black South African students were lower in magnitude on all subscales than those for American, Dutch, and White South African samples, but intercorrelations between subscale scores were consistent. Findings in the present study are supportive of the cross-cultural applicability of the Irrational Beliefs Inventory to White South African students but not to South African Black students. PMID:15666916

  10. Crustal and upper mantle investigations of the Caribbean-South American plate boundary

    NASA Astrophysics Data System (ADS)

    Bezada, Maximiliano J.

    The evolution of the Caribbean --- South America plate boundary has been a matter of vigorous debate for decades and many questions remain unresolved. In this work, and in the framework of the BOLIVAR project, we shed light on some aspects of the present state and the tectonic history of the margin by using different types of geophysical data sets and techniques. An analysis of controlled-source traveltime data collected along a boundary-normal profile at ˜65°W was used to build a 2D P-wave velocity model. The model shows that the Caribbean Large Igenous Province is present offshore eastern Venezuela and confirms the uniformity of the velocity structure along the Leeward Antilles volcanic belt. In contrast with neighboring profiles, at this longitude we see no change in velocity structure or crustal thickness across the San Sebastian - El Pilar fault system. A 2D gravity modeling methodology that uses seismically derived initial density models was developed as part of this research. The application of this new method to four of the BOLIVAR boundary-normal profiles suggests that the uppermost mantle is denser under the South American continental crust and the island arc terranes than under the Caribbean oceanic crust. Crustal rocks of the island arc and extended island arc terranes of the Leeward Antilles have a relatively low density, given their P-wave velocity. This may be caused by low iron content, relative to average magmatic arc rocks. Finally, an analysis of teleseismic traveltimes with frequency-dependent kernels produced a 3D P-wave velocity perturbation model. The model shows the structure of the mantle lithosphere under the study area and clearly images the subduction of the Atlantic slab and associated partial removal of the lower lithosphere under northern South America. We also image the subduction of a section of the Caribbean plate under South America with an east-southeast direction. Both the Atlantic and Caribbean subducting slabs penetrate the

  11. Drainage Analysis of the South American Landscape and its Tectonic Implications

    NASA Astrophysics Data System (ADS)

    Rodríguez Tribaldos, Verónica; White, Nicholas J.; Roberts, Gareth G.

    2016-04-01

    last 25-30 Ma. Our results are consistent with a wide range of independent geological observations across South America (e.g. elevated marine deposits, thermochronology, paleoelevation estimates from paleobotany, standard/clumped isotopes analyses). Finally, an important test of our thesis concerns offshore sedimentary flux. For example, our calculated uplift history can be used to predict the history of sedimentary flux into the Foz do Amazonas basin. This prediction agrees with offshore studies of the Amazon delta which suggest a rapid increase in clastic deposition since middle Miocene times. In summary, we propose that South American drainage contains useful information about spatial and temporal patterns of regional uplift which can help our understanding of regional topographic growth and landscape evolution.

  12. A 5000 Year Record of Andean South American Summer Monsoon Variability from Laguna de Ubaque, Colombia

    NASA Astrophysics Data System (ADS)

    Rudloff, O. M.; Bird, B. W.; Escobar, J.

    2014-12-01

    Our understanding of Northern Hemisphere South American summer monsoon (SASM) dynamics during the Holocene has been limited by the small number of terrestrial paleoclimate records from this region. In order to increase our knowledge of SASM variability and to better inform our predictions of its response to ongoing rapid climate change, we require high-resolution paleoclimate records from the Northern Hemisphere Andes. To this end, we present sub-decadally resolved sedimentological and geochemical data from Laguna de Ubaque that spans the last 5000 years. Located in the Eastern Cordillera of the Colombian Andes, Laguna de Ubaque (2070 m asl) is a small, east facing moraine-dammed lake in the upper part of the Rio Meta watershed near Bogotá containing finely laminated clastic sediments. Dry bulk density, %organic matter, %carbonate and magnetic susceptibility (MS) results from Ubaque suggest a period of intense precipitation between 3500 and 2000 years BP interrupted by a 300 yr dry interval centered at 2700 years BP. Following this event, generally drier conditions characterize the last 2000 years. Although considerably lower amplitude than the middle Holocene pluvial events, variability in the sedimentological data support climatic responses during the Medieval Climate Anomaly (MCA; 900 to 1200 CE) and Little Ice Age (LIA; 1450 to 1900 CE) that are consistent with other records of local Andean conditions. In particular, reduced MS during the MCA suggests a reduction in terrestrial material being washed into the lake as a result of generally drier conditions. The LIA on the other hand shows a two phase structure with increased MS between 1450 and 1600 CE, suggesting wetter conditions during the onset of the LIA, and reduced MS between 1600 and 1900 CE, suggesting a return to drier conditions during the latter part of the LIA. These LIA trends are similar to the Quelccaya accumulation record, possibly supporting an in-phase relationship between the South American

  13. Comparable ages for the independent origins of electrogenesis in African and South American weakly electric fishes.

    PubMed

    Lavoué, Sébastien; Miya, Masaki; Arnegard, Matthew E; Sullivan, John P; Hopkins, Carl D; Nishida, Mutsumi

    2012-01-01

    One of the most remarkable examples of convergent evolution among vertebrates is illustrated by the independent origins of an active electric sense in South American and African weakly electric fishes, the Gymnotiformes and Mormyroidea, respectively. These groups independently evolved similar complex systems for object localization and communication via the generation and reception of weak electric fields. While good estimates of divergence times are critical to understanding the temporal context for the evolution and diversification of these two groups, their respective ages have been difficult to estimate due to the absence of an informative fossil record, use of strict molecular clock models in previous studies, and/or incomplete taxonomic sampling. Here, we examine the timing of the origins of the Gymnotiformes and the Mormyroidea using complete mitogenome sequences and a parametric bayesian method for divergence time reconstruction. Under two different fossil-based calibration methods, we estimated similar ages for the independent origins of the Mormyroidea and Gymnotiformes. Our absolute estimates for the origins of these groups either slightly postdate, or just predate, the final separation of Africa and South America by continental drift. The most recent common ancestor of the Mormyroidea and Gymnotiformes was found to be a non-electrogenic basal teleost living more than 85 millions years earlier. For both electric fish lineages, we also estimated similar intervals (16-19 or 22-26 million years, depending on calibration method) between the appearance of electroreception and the origin of myogenic electric organs, providing rough upper estimates for the time periods during which these complex electric organs evolved de novo from skeletal muscle precursors. The fact that the Gymnotiformes and Mormyroidea are of similar age enhances the comparative value of the weakly electric fish system for investigating pathways to evolutionary novelty, as well as the

  14. Annual South American Forest Loss Estimates (1989-2011) Based on Passive Microwave Remote Sensing

    NASA Astrophysics Data System (ADS)

    van Marle, M.; van der Werf, G.; de Jeu, R.; Liu, Y.

    2014-12-01

    Vegetation dynamics, such as forest loss, are an important factor in global climate, but long-term and consistent information on these dynamics on continental scales is lacking. We have quantified large-scale forest loss over the 90s and 00s in the tropical biomes of South America using a passive-microwave satellite-based vegetation product. Our forest loss estimates are based on remotely sensed vegetation optical depth (VOD), which is an indicator of vegetation water content simultaneously retrieved with soil moisture. The advantage of low-frequency microwave remote sensing is that aerosols and clouds do not affect the observations. Furthermore, the longer wavelengths of passive microwaves penetrate deeper into vegetation than other products derived from optical and thermal sensors. This has the consequence that both woody parts of vegetation and leaves can be observed. The merged VOD product of AMSR-E and SSM/I observations, which covers over 23 years of daily observations, is used. We used this data stream and an outlier detection algorithm to quantify spatial and temporal variations in forest loss dynamics. Qualitatively, our results compared favorably to the newly developed Global Forest Change (GFC) maps based on Landsat data (r2=0.96), and this allowed us to convert the VOD outlier count to forest loss. Our results are spatially explicit with a 0.25-degree resolution and annual time step and we will present our estimates on country level. The added benefit of our results compared to GFC is the longer time period. The results indicate a relatively steady increase in forest loss in Brazil from 1989 until 2003, followed by two high forest loss years and a declining trend afterwards. This contrasts with other South American countries such as Bolivia and Peru, where forest losses increased in almost the whole 00s in comparison with the 90s.

  15. Functional morphology and wasp pollination of two South American asclepiads (Asclepiadoideae–Apocynaceae)

    PubMed Central

    Wiemer, A. P.; Sérsic, A. N.; Marino, S.; Simões, A. O.; Cocucci, A. A.

    2012-01-01

    Background and Aims The extreme complexity of asclepiad flowers (Asclepiadoideae–Apocynaceae) has generated particular interest in the pollination biology of this group of plants especially in the mechanisms involved in the pollination processes. This study compares two South American species, Morrenia odorata and Morrenia brachystephana, with respect to morphology and anatomy of flower structures, dynamic aspects of the pollination mechanism, diversity of visitors and effectiveness of pollinators. Methods Floral structure was studied with fresh and fixed flowers following classical techniques. The pollination mechanism was studied by visiting fresh flowers in the laboratory with artificial pollinator body parts created with an eyelash. Morphometric and nectar measurements were also taken. Pollen transfer efficiency in the flowers was calculated by recording the frequency of removed and inserted pollinia. Visitor activity was recorded in the field, and floral visitors were captured for subsequent analysis of pollen loads. Finally, pollinator effectiveness was calculated with an index. Key Results The detailed structure of the flowers revealed a complex system of guide rails and chambers precisely arranged in order to achieve effective pollinaria transport. Morrenia odorata is functionally specialized for wasp pollination, and M. brachystephana for wasp and bee pollination. Pollinators transport chains of pollinaria adhered to their mouthparts. Conclusions Morrenia odorata and M. brachystephana present differences in the morphology and size of their corona, gynostegium and pollinaria, which explain the differences in details of the functioning of the general pollination mechanism. Pollination is performed by different groups of highly effective pollinators. Morrenia species are specialized for pollination mainly by several species of wasps, a specialized pollination which has been poorly studied. In particular, pompilid wasps are reported as important pollinators

  16. The South American Meridional B-field Array (SAMBA) and Pc4-5 Wave Studies

    NASA Astrophysics Data System (ADS)

    Sterner, Lt. Nathan; Zesta, Eftyhia; Boudouridis, Athanasios; Moldwin, Mark; Yizengaw, Endawoke; Chi, Peter

    The Antarctic continent, the only landmass in the southern polar region, offers the unique opportunity for observations that geomagnetically range from polar latitudes to well into the inner magnetosphere, thus enabling conjugate observations in a wide range of geomagnetic lat-itudes. The SAMBA (South American Meridional B-field Array) chain is a meridional chain of 12 magnetometers, 11 of them at L=1.1 to L=2.5 along the coast of Chile and in the Antarc-tica peninsula, and one auroral station along the same meridian. SAMBA is conjugate to the northern hemisphere MEASURE and McMAC chains, offering unique opportunities for inter-hemispheric studies. In particular, we study asymmetries in the power of ULF waves and the role of the ionosphere in such observed asymmetries. Utilizing conjugate magnetometer stations at L=1.7 and L=2.3, we previously demonstrated that the northern hemisphere consistently shows higher ULF wave power. One possible reason for the asymmetry is solar zenith angles differences with the northern hemisphere station being closer to the ecliptic plain and having a higher power ratio. These hemispheric differences were also observed with TEC measurements indicating that the north and south conjugate ionospheres are similarly asymmetric. The initial study was done with Pc3 waves, which include the resonance frequencies for the flux tubes of our conjugate stations. We now extend the study to Pc4 and Pc5 waves that reach the lower latitudes via different mechanisms and compare these waves to the resonant Pc3 waves.

  17. Comparable Ages for the Independent Origins of Electrogenesis in African and South American Weakly Electric Fishes

    PubMed Central

    Lavoué, Sébastien; Miya, Masaki; Arnegard, Matthew E.; Sullivan, John P.; Hopkins, Carl D.; Nishida, Mutsumi

    2012-01-01

    One of the most remarkable examples of convergent evolution among vertebrates is illustrated by the independent origins of an active electric sense in South American and African weakly electric fishes, the Gymnotiformes and Mormyroidea, respectively. These groups independently evolved similar complex systems for object localization and communication via the generation and reception of weak electric fields. While good estimates of divergence times are critical to understanding the temporal context for the evolution and diversification of these two groups, their respective ages have been difficult to estimate due to the absence of an informative fossil record, use of strict molecular clock models in previous studies, and/or incomplete taxonomic sampling. Here, we examine the timing of the origins of the Gymnotiformes and the Mormyroidea using complete mitogenome sequences and a parametric Bayesian method for divergence time reconstruction. Under two different fossil-based calibration methods, we estimated similar ages for the independent origins of the Mormyroidea and Gymnotiformes. Our absolute estimates for the origins of these groups either slightly postdate, or just predate, the final separation of Africa and South America by continental drift. The most recent common ancestor of the Mormyroidea and Gymnotiformes was found to be a non-electrogenic basal teleost living more than 85 millions years earlier. For both electric fish lineages, we also estimated similar intervals (16–19 or 22–26 million years, depending on calibration method) between the appearance of electroreception and the origin of myogenic electric organs, providing rough upper estimates for the time periods during which these complex electric organs evolved de novo from skeletal muscle precursors. The fact that the Gymnotiformes and Mormyroidea are of similar age enhances the comparative value of the weakly electric fish system for investigating pathways to evolutionary novelty, as well as the

  18. Genetic divergence disclosing a rapid prehistorical dispersion of Native Americans in Central and South America.

    PubMed

    He, Yungang; Wang, Wei R; Li, Ran; Wang, Sijia; Jin, Li

    2012-01-01

    An accurate estimate of the divergence time between Native Americans is important for understanding the initial entry and early dispersion of human beings in the New World. Current methods for estimating the genetic divergence time of populations could seriously depart from a linear relationship with the true divergence for multiple populations of a different population size and significant population expansion. Here, to address this problem, we propose a novel measure to estimate the genetic divergence time of populations. Computer simulation revealed that the new measure maintained an excellent linear correlation with the population divergence time in complicated multi-population scenarios with population expansion. Utilizing the new measure and microsatellite data of 21 Native American populations, we investigated the genetic divergences of the Native American populations. The results indicated that genetic divergences between North American populations are greater than that between Central and South American populations. None of the divergences, however, were large enough to constitute convincing evidence supporting the two-wave or multi-wave migration model for the initial entry of human beings into America. The genetic affinity of the Native American populations was further explored using Neighbor-Net and the genetic divergences suggested that these populations could be categorized into four genetic groups living in four different ecologic zones. The divergence of the population groups suggests that the early dispersion of human beings in America was a multi-step procedure. Further, the divergences suggest the rapid dispersion of Native Americans in Central and South Americas after a long standstill period in North America. PMID:22970308

  19. Genetic Divergence Disclosing a Rapid Prehistorical Dispersion of Native Americans in Central and South America

    PubMed Central

    He, Yungang; Wang, Wei R.; Li, Ran; Wang, Sijia; Jin, Li

    2012-01-01

    An accurate estimate of the divergence time between Native Americans is important for understanding the initial entry and early dispersion of human beings in the New World. Current methods for estimating the genetic divergence time of populations could seriously depart from a linear relationship with the true divergence for multiple populations of a different population size and significant population expansion. Here, to address this problem, we propose a novel measure to estimate the genetic divergence time of populations. Computer simulation revealed that the new measure maintained an excellent linear correlation with the population divergence time in complicated multi-population scenarios with population expansion. Utilizing the new measure and microsatellite data of 21 Native American populations, we investigated the genetic divergences of the Native American populations. The results indicated that genetic divergences between North American populations are greater than that between Central and South American populations. None of the divergences, however, were large enough to constitute convincing evidence supporting the two-wave or multi-wave migration model for the initial entry of human beings into America. The genetic affinity of the Native American populations was further explored using Neighbor-Net and the genetic divergences suggested that these populations could be categorized into four genetic groups living in four different ecologic zones. The divergence of the population groups suggests that the early dispersion of human beings in America was a multi-step procedure. Further, the divergences suggest the rapid dispersion of Native Americans in Central and South Americas after a long standstill period in North America. PMID:22970308

  20. The simultaneous diversification of South American echimyid rodents (Hystricognathi) based on complete cytochrome b sequences.

    PubMed

    Lara, M C; Patton, J L; da Silva, M N

    1996-04-01

    Variation in the complete nucleotide sequence of the mitochondrial cytochrome b gene was examined for 32 individuals representing 12 supraspecific taxa of South American rodents of the family Echimyidae (Hystricognathi). Representative genera of four other New World hystricognath families, the Old World porcupine Hystrix, and the myomorph murid rodents Rattus and Mus were used as outgroups in phylogenetic reconstructions. Monopoly of the family Echimyidae is strongly supported, a result fully consistent with existing morphological and paleontological data relative to the taxa examined. However, relationships among most supraspecific taxa within the family are poorly resolved. Poor resolution appears not to result from lack of data, but to a rapid, nearly simultaneous divergence of most Recent taxa. Generic groupings that are moderately to strongly supported include the tree rats of the Brazilian Atlantic Forest (Nelomys) and Amazonia (Echimys, Makalata) and the Amazonian arboreal spiny rats Mesomys and Lonchothrix. However, the two subgenera of the terrestrial spiny rats, Proechimys, do not form a monophyletic unit, and elevation of the Atlantic Forest Trinomys to generic status is supported. The genus Hoplomys is closely related to Proechimys (sensu stricto), a finding supported by other molecular data. PMID:8728398

  1. Bluetongue disease and seroprevalence in South American camelids from the northwestern region of the United States.

    PubMed

    Allen, Andrew J; Stanton, James B; Evermann, James F; Fry, Lindsay M; Ackerman, Melissa G; Barrington, George M

    2015-03-01

    In late summer/early fall of 2013, 2 South American camelids from central Washington were diagnosed with fatal bluetongue viral disease, an event which is rarely reported. A 9-year-old intact male llama (Lama glama), with a 1-day history of anorexia, recumbency, and dyspnea before death. Abundant foam discharged from the mouth and nostrils, and the lungs were severely edematous on postmortem examination. Histologically, there was abundant intra-alveolar edema with fibrin. Hemorrhage and edema disrupted several other organs. Bluetongue viral RNA was detected by reverse transcription polymerase chain reaction (RT-PCR), and serotype 11 was identified by sequencing a segment of the VP2 outer capsid gene. Approximately 1 month later, at a site 150 miles north of the index case, a 2-year-old female alpaca with similar, acutely progressive clinical signs was reported. A postmortem examination was performed, and histologic lesions from the alpaca were similar to those of the llama, and again serotype 11 was detected by PCR. The occurrence of bluetongue viral infection and disease is described in the context of seasonal Bluetongue virus activity within the northwestern United States and southwestern Canada. PMID:25680921

  2. Centennial-scale solar forcing of the South American Monsoon System recorded in stalagmites.

    PubMed

    Novello, Valdir F; Vuille, Mathias; Cruz, Francisco W; Stríkis, Nicolás M; de Paula, Marcos Saito; Edwards, R Lawrence; Cheng, Hai; Karmann, Ivo; Jaqueto, Plínio F; Trindade, Ricardo I F; Hartmann, Gelvam A; Moquet, Jean S

    2016-01-01

    The South American Monsoon System (SAMS) is generally considered to be highly sensitive to Northern Hemisphere (NH) temperature variations on multi-centennial timescales. The direct influence of solar forcing on moisture convergence in global monsoon systems on the other hand, while well explored in modeling studies, has hitherto not been documented in proxy data from the SAMS region. Hence little is known about the sensitivity of the SAMS to solar forcing over the past millennium and how it might compete or constructively interfere with NH temperature variations that occurred primarily in response to volcanic forcing. Here we present a new annually-resolved oxygen isotope record from a 1500-year long stalagmite recording past changes in precipitation in the hitherto unsampled core region of the SAMS. This record details how solar variability consistently modulated the strength of the SAMS on centennial time scales during the past 1500 years. Solar forcing, besides the previously recognized influence from NH temperature changes and associated Intertropical Convergence Zone (ITCZ) shifts, appears as a major driver affecting SAMS intensity at centennial time scales. PMID:27097590

  3. Anthelmintic effects of a cationic toxin from a South American rattlesnake venom.

    PubMed

    Dal Mas, C; Moreira, J T; Pinto, S; Monte, G G; Nering, M B; Oliveira, E B; Gazarini, M L; Mori, M A; Hayashi, M A F

    2016-06-15

    Despite the unquestionable importance of the highly cationic feature of several small polypeptides with high content of positively charged amino acids for their biological activities, positively charged peptides do not necessarily have the capacity to cross the cell membranes. Interestingly, we found that crotamine, a positively charged amphiphilic peptide from the South American rattlesnake venom, has a unique cell-penetrating property with affinity for acidic vesicles, besides a well-characterized antimicrobial and antitumoral activities. In spite of a remarkable in vitro antifungal activity of crotamine against Candida spp., no significant effect of this peptide could be observed in the course of Candida albicans and Candida krusei infection on Caenorhabditis elegans asssed in vivo. These experiments, in which the nematode C. elegans was used as a living host, suggested, however, the potential anthelmintic activity of crotamine because of its uptake by the worms and accumulation in their acidic compartments. As described in the present work, this lysosomotropic property is consistent with a previously proposed mechanism of toxicity of crotamine on mammalian tumoral cell lines. This study also allowed us to propose the cationic peptides with lysosomotropic property, as crotamine, as a potential new class of anthelmentics with ability to overcome the challenging problems of drug resistance. PMID:26713409

  4. Massive Muscular Infection by a Sarcocystis Species in a South American Rattlesnake (Crotalus durissus terrificus).

    PubMed

    Roberts, J F; Wellehan, J F X; Weisman, J L; Rush, M; Childress, A L; Lindsay, David S

    2015-06-01

    Massive numbers of sarcocysts of a previously undescribed species of Sarcocystis were observed in the skeletal muscles throughout the body of an adult, female South American rattlesnake (Crotalus durissus terrificus). Examination of tissue sections by light microscopy demonstrated that sarcocysts were present in 20 to 40% of muscle fibers from 5 sampled locations. Sarcocysts were not present in cardiac muscle, smooth muscle, or other organs. Sarcocysts were 0.05-0.15 mm wide, had variable length depending on the viewed orientation and size of the muscle fiber, and had a sarcocyst wall less than 1-μm thick. Sarcocysts were subdivided by septa and had central degeneration in older sarcocysts. Host induced secondary encapsulation or an inflammatory response was not present. By transmission electron microscopy (TEM), the sarcocyst wall was Type I, with a parasitophorous membrane of approximately 100 nanometers in width arranged in an undulating pattern and intermittently folded inward in a branching pattern. The sarcocysts contained metrocytes in different stages of development and mature bradyzoites. The nucleic acid sequence from a section of the 18S small subunit rRNA gene was most closely related to S. mucosa that uses marsupials as intermediate hosts and has an unknown definitive host. This is apparently the third report of muscular Sarcocystis infection in snakes and is the first to describe the ultrastructure of the sarcocysts and use sequencing methods to aid in identification. PMID:25658773

  5. [First detection of "Candidatus Mycoplasma haemolamae" in South American Camelids of Switzerland and evaluation of prevalence].

    PubMed

    Kaufmann, Christine; Meli, Marina L; Hofmann-Lehmann, Regina; Zanolari, Patrik

    2010-01-01

    Haemotrophic mycoplasmas (also known as haemoplasmas), small bacterias which parasite the surface of erythrocytes, have been described in several species. Recently, molecular methods were developed for the diagnosis of haemoplasma infection. The presented study describes the first detection and the investigation of prevalence of "Candidatus Mycoplasma haemolamae" in South American Camelids in Switzerland. A random sample of the latter population was tested for haemoplasma infections using real-time PCR. The infection was detected in 18.6% of the animals and was found both in indigenous and in imported camelids. Of the tested herds 39,1% harboured at least one animal positive for haemoplasmas in PCR. There was no difference in prevalence between male and female animals and llamas and alpacas, respectively. Furthermore, the prevalence of infection was not significantly different in diseased animals compared to healthy camelids. From the latter observation and the fact that the high prevalence was accompanied by an undetectable incidence, we concluded that the pathogenicity of "Candidatus Mycoplasma haemolamae" may be low. PMID:21141277

  6. Sarcocystis lindsayi n. sp. (Protozoa: Sarcocystidae) from the South American opossum, Didelphis albiventris from Brazil.

    PubMed

    Dubey, J P; Rosenthal, B M; Speer, C A

    2001-01-01

    A new species, Sarcocystis lindsayi n. sp., is proposed for a parasite resembling Sarcocystis falcatula. It was obtained from the lungs and muscles of budgerigars (Melopsittacus undulatus) fed sporocysts from a naturally-infected South American opossum, Didelphis albiventris, from Jaboticabal, Brazil. Sarcocysts of S. lindsayi n. sp. in budgerigars are microscopic, up to 600 microm long and up to 50 microm wide. The cyst wall is up to 2 microm thick. Ultrastructurally, the sarcocyst wall consists of numerous slender villar protrusions (up to 2.0 microm long and up to 0.3 microm wide), each with a stylet at its tip. Schizonts in cell culture divide by endopolygeny leaving a residual body. Sporocysts are approximately 12 x 7 microm. The parasite is genetically distinct from other organisms that also cycle between opossums and avian species and resemble S. falcatula. Diagnostic genetic variation has been observed in the nuclear large subunit ribosomal RNA gene, the internal transcribed spacer (ITS-1), and each of two other genetic loci. Although the structure of the sarcocyst wall may not provide sufficient grounds for differential diagnosis, several other attributes including schizont morphology and genetic variation at each of these genetic loci permit identification of S. lindsayi n. sp.. Natural intermediate hosts for S. lindsayi n. sp. are not known, and fuller characterization of these and other Sarcocystis species would benefit from experimental avian hosts that are more permissive to the maturation of sarcocysts. PMID:11596925

  7. Evaluating detection probabilities for American marten in the Black Hills, South Dakota

    USGS Publications Warehouse

    Smith, J.B.; Jenks, J.A.; Klaver, R.W.

    2007-01-01

    Assessing the effectiveness of monitoring techniques designed to determine presence of forest carnivores, such as American marten (Martes americana), is crucial for validation of survey results. Although comparisons between techniques have been made, little attention has been paid to the issue of detection probabilities (p). Thus, the underlying assumption has been that detection probabilities equal 1.0. We used presence-absence data obtained from a track-plate survey in conjunction with results from a saturation-trapping study to derive detection probabilities when marten occurred at high (>2 marten/10.2 km2) and low (???1 marten/10.2 km2) densities within 8 10.2-km2 quadrats. Estimated probability of detecting marten in high-density quadrats was p = 0.952 (SE = 0.047), whereas the detection probability for low-density quadrats was considerably lower (p = 0.333, SE = 0.136). Our results indicated that failure to account for imperfect detection could lead to an underestimation of marten presence in 15-52% of low-density quadrats in the Black Hills, South Dakota, USA. We recommend that repeated site-survey data be analyzed to assess detection probabilities when documenting carnivore survey results.

  8. Moisture and heat budgets of the south American monsoon system: climatological aspects

    NASA Astrophysics Data System (ADS)

    Garcia, Sâmia R.; Kayano, Mary T.; Calheiros, Alan J. P.; Andreoli, Rita Valéria; de Souza, Rodrigo Augusto Ferreira

    2016-08-01

    The climatology of the moisture and heat budget equation terms for subareas within the South American Monsoon System (SAMS) region is investigated for the 1958-2014 period considering the distinct phases of the Pacific Decadal Oscillation (PDO). These budget equations are applied to the data from the National Centers for Environmental Prediction (NCEP) Reanalysis project. Sources or sinks of moisture and heat are equation residues, referred to as residue and diabatic terms, respectively. Analyses are done for the Central Amazon Basin (CAM) and Western-Central Brazil (WCB) for three distinct periods, 1958-1976, 1977-1995, and 1996-2014, that correspond to the cold, warm, and undefined PDO phases. The differences among the PDO phases for each term are discussed. The CAM region acts dominantly as a moisture sink and heat source in all months during the three phases. On the other hand, in the WCB region, the monsoon characteristics are better defined, with a moisture sink (source) and a heat source (sink) during the wet (dry) season. The main result of the present analysis is the persistence of SAMS intensification signs in both CAM and WCB areas up to the last analyzed period (1996-2014), which is consistent with intense flooding in the Amazon Basin in 2008/2009, 2012, and 2014.

  9. Practicing What They Preach? Lynching and Religion in the American South, 1890 – 1929*

    PubMed Central

    Bailey, Amy Kate; Snedker, Karen A.

    2013-01-01

    This project employs a moral solidarity framework to explore the relationship between organized religion and lynching in the American South. We ask whether a county’s religious composition impacted its rate of lynching, net of demographic and economic controls. We find evidence for the solidarity thesis using three religious metrics. First, our findings show that counties with greater religious diversity experienced more lynching, supporting the notion that a pluralistic religious marketplace with competing religious denominations weakened the bonds of a cohesive moral community and might have enhanced white racial solidarity. Second, counties in which a larger share of the black population worshipped in churches controlled by blacks experienced higher levels of racial violence, indicating a threat to the prevailing moral community or inter-group racially based solidarity. Finally, we find a lower incidence of lynching in counties where a larger share of church members belonged to denominations with racially mixed denominations, suggesting that cross-racial solidarity served to reduce racial violence. PMID:24327771

  10. Marine parasites as biological tags in South American Atlantic waters, current status and perspectives.

    PubMed

    Cantatore, D M P; Timi, J T

    2015-01-01

    Many marine fisheries in South American Atlantic coasts (SAAC) are threatened by overfishing and under serious risk of collapsing. The SAAC comprises a diversity of environments, possesses a complex oceanography and harbours a vast biodiversity that provide an enormous potential for using parasites as biological tags for fish stock delineation, a prerequisite for the implementation of control and management plans. Here, their use in the SAAC is reviewed. Main evidence is derived from northern Argentine waters, where fish parasite assemblages are dominated by larval helminth species that share a low specificity, long persistence and trophic transmission, parasitizing almost indiscriminately all available fish species. The advantages and constraints of such a combination of characteristics are analysed and recommendations are given for future research. Shifting the focus from fish/parasite populations to communities allows expanding the concept of biological tags from local to regional scales, providing essential information to delineate ecosystem boundaries for host communities. This new concept arose as a powerful tool to help the implementation of ecosystem-based approaches to fisheries management, the new paradigm for fisheries science. Holistic approaches, including parasites as biological tags for stock delineation will render valuable information to help insure fisheries and marine ecosystems against further depletion and collapse. PMID:24477070

  11. How Many Parasites Species a Frog Might Have? Determinants of Parasite Diversity in South American Anurans

    PubMed Central

    Campião, Karla Magalhães; Ribas, Augusto Cesar de Aquino; Morais, Drausio Honorio; da Silva, Reinaldo José; Tavares, Luiz Eduardo Roland

    2015-01-01

    There is an increasing interest in unveiling the dynamics of parasite infection. Understanding the interaction patterns, and determinants of host-parasite association contributes to filling knowledge gaps in both community and disease ecology. Despite being targeted as a relevant group for conservation efforts, determinants of the association of amphibians and their parasites in broad scales are poorly understood. Here we describe parasite biodiversity in South American amphibians, testing the influence of host body size and geographic range in helminth parasites species richness (PSR). We also test whether parasite diversity is related to hosts’ phylogenetic diversity. Results showed that nematodes are the most common anuran parasites. Host-parasite network has a nested pattern, with specialist helminth taxa generally associated with hosts that harbour the richest parasite faunas. Host size is positively correlated with helminth fauna richness, but we found no support for the association of host geographic range and PSR. These results remained consistent after correcting for uneven study effort and hosts’ phylogenic correlation. However, we found no association between host and parasite diversity, indicating that more diversified anuran clades not necessarily support higher parasite diversity. Overall, considering both the structure and the determinants of PRS in anurans, we conclude that specialist parasites are more likely to be associated with large anurans, which are the ones harbouring higher PSR, and that the lack of association of PSR with hosts’ clade diversification suggests it is strongly influenced by ecological and contemporary constrains. PMID:26473593

  12. Decompressive Hemicraniectomy in a South American Population – Morbidity and Outcomes Analysis

    PubMed Central

    Vital, Roberto Bezerra; Hamamoto Filho, Pedro Tadao; Luvizutto, Gustavo Jose; Ducati, Luis Gustavo; Braga, Gabriel Pereira; Nunes, Helio Rubens de Carvalho; Romero, Flavio Ramalho; Ganem, Eliana Marisa; Zanini, Marco Antonio; Bazan, Rodrigo

    2016-01-01

    Background Malignant cerebral artery strokes have a poor prognosis, with nearly 80% of mortality in some series despite intensive care. After a large randomized trial, decompressive hemicraniectomy has been performed more often in stroke patients. Here, we describe patients in a tertiary teaching hospital in Brazil, emphasizing the impact of age on outcomes. Methods A retrospective cohort of patients, with malignant strokes which received a decompressive hemicraniectomy, from paper and electronic medical records, from January 2010 to December 2013 was divided into two groups according to age. Results The final analysis included 60 patients. The overall mortality was higher among patients older than 60 yrs (67% vs. 41%; p = 0.039), whose group also had a worse outcome (76% with mRS 5 or 6) at 90 days (OR 3.91 CI95% 1.30–11.74), whereas only 24% had mRS of 0–4 (p = 0.015). All patients who presented with sepsis died (p = 0.003). The incidence of pulmonary infection was very high in the elderly group (76%) with significant intergroup differences (p = 0.027, OR 8.32 CI95% 0.70–98.48). Conclusions Older patients present more commonly with infections, more disabilities and a higher mortality, highlighting very poor results in elderly population. These results should be proved with a South American trial, and if confirmed, it can impact on future decisions regarding decompressive craniectomy for acute ischemic stroke in our region. PMID:26764485

  13. Toxicity of endosulfan on embryo-larval development of the South American toad Rhinella arenarum.

    PubMed

    Svartz, Gabriela V; Wolkowicz, Ianina R Hutler; Coll, Cristina S Pérez

    2014-04-01

    Endosulfan is a widely used pesticide despite its extreme toxicity to a variety of taxa and its worldwide ban. The aim of the present study was to evaluate the acute and chronic toxicity of endosulfan on the embryonic-larval development of the common South American toad Rhinella arenarum. The results showed that lethal and sublethal effects increased with concentration and exposure time. The sensitivity to endosulfan increased during the larval period, the complete operculum stage (S.25) being the most sensitive (504-h median lethal concentration [LC50] = 0.01 mg endosulfan/L; 10% lethal concentration [LC10] = 0.004 mg endosulfan/L). Endosulfan exposure caused morphological abnormalities such as general underdevelopment, edema, gill malformations, and cellular dissociation as well as neurotoxicity. Our results also showed that larvae exposed to concentrations of 0.005 mg endosulfan/L and 0.01 mg endosulfan/L completed metamorphosis earlier than controls, but with underdevelopment. The 240-h teratogenic index was 6.13, implying a high risk for embryos to be malformed in the absence of significant embryonic lethality. Because the hazard quotients for chronic exposure were over 1, the level of concern value and toxicity endpoints obtained in the present study for R. arenarum occurred at concentrations lower than the levels of endosulfan reported in the environment, this pesticide should be considered a potential risk for this species. PMID:24375551

  14. Interdecadal change in the lagged relationship between the Pacific-South American pattern and ENSO

    NASA Astrophysics Data System (ADS)

    Ding, Ruiqiang; Li, Jianping; Tseng, Yu-heng; Ha, Kyung-Ja; Zhao, Sen; Lee, June-Yi

    2016-01-01

    A significant interdecadal change in the lagged relationship between the austral summer Pacific-South American (PSA) pattern and the El Niño-Southern Oscillation (ENSO) in the following austral summer (the PSA serving as a precursor signature to ENSO events) has been detected by analysis of a 91-year historical record. Strong correlations between the PSA and ENSO occurred during the periods 1956-1975 and 1990-2004 [referred to as the high correlation (HC) periods], but the correlations were weak for the periods 1928-1956 and 1975-1990 [referred to as the low correlation (LC) periods]. Both the processes of surface air-sea coupling in the extratropical/tropical Pacific, and subsurface ocean temperature evolution along the equator associated with the PSA, were found to be stronger during the HC periods than during the LC periods, thereby resulting in a stronger influence of the PSA on the subsequent ENSO during the HC periods. Changes in the PSA-ENSO relationship can be attributed mainly to interdecadal changes in the intensity of the austral summer PSA. The latter was found to have contributions from both the modulation of the Pacific decadal oscillation and long-term variations in the Southern Annular Mode.

  15. Oxygen consumption and thermoregulatory responses in three species of South American marsupials.

    PubMed

    Ribeiro, Marcel Cintra Pereira; Bicudo, José Eduardo Pereira Wilken

    2007-07-01

    Oxygen consumption (VO(2)), body temperature (T(b)) and wet thermal conductance (C(wet)), under resting conditions, exposure to low ambient temperature (T(a)) and during sustained exercise (treadmill running) were measured in three phylogenetic related (same family; Didelphidae) South American marsupials possessing similar body masses: Caluromys philander (arboreal/fruit and insect eating), Philander opossum (terrestrial and arboreal/omnivore), and Metachirus nudicaudatus (terrestrial/omnivore). Our measurements of VO(2) and C(wet) under resting conditions agree with those previously reported for other marsupials. We expected that C. philander would show a lower maximal sustained VO(2), compared to the other two species, based on its more reduced skeletal muscle mass. However, the values obtained for C. philander were not statistically different (ANOVA) from those obtained for the other two species. When exposed to low ambient temperature (12 degrees C), differences among the three species were detected, i.e., M. nudicaudatus did not survive, while the other two species were able to reduce their T(b) under such conditions. C. philander gradually decreases its T(b) when cold exposed, and P. opossum shows a more pronounced T(b) drop only when exposure to low ambient temperatures occurs for a more prolonged period of time. PMID:17020814

  16. Centennial-scale solar forcing of the South American Monsoon System recorded in stalagmites

    NASA Astrophysics Data System (ADS)

    Novello, Valdir F.; Vuille, Mathias; Cruz, Francisco W.; Stríkis, Nicolás M.; de Paula, Marcos Saito; Edwards, R. Lawrence; Cheng, Hai; Karmann, Ivo; Jaqueto, Plínio F.; Trindade, Ricardo I. F.; Hartmann, Gelvam A.; Moquet, Jean S.

    2016-04-01

    The South American Monsoon System (SAMS) is generally considered to be highly sensitive to Northern Hemisphere (NH) temperature variations on multi-centennial timescales. The direct influence of solar forcing on moisture convergence in global monsoon systems on the other hand, while well explored in modeling studies, has hitherto not been documented in proxy data from the SAMS region. Hence little is known about the sensitivity of the SAMS to solar forcing over the past millennium and how it might compete or constructively interfere with NH temperature variations that occurred primarily in response to volcanic forcing. Here we present a new annually-resolved oxygen isotope record from a 1500-year long stalagmite recording past changes in precipitation in the hitherto unsampled core region of the SAMS. This record details how solar variability consistently modulated the strength of the SAMS on centennial time scales during the past 1500 years. Solar forcing, besides the previously recognized influence from NH temperature changes and associated Intertropical Convergence Zone (ITCZ) shifts, appears as a major driver affecting SAMS intensity at centennial time scales.

  17. Complex networks identify spatial patterns of extreme rainfall of the South American monsoon system

    NASA Astrophysics Data System (ADS)

    Boers, Niklas; Bokkhagen, Bodo; Marwan, Norbert; Kurths, Jürgen; Marengo, Jose

    2014-05-01

    In this study, we investigate the spatial characteristics of extreme rainfall synchronicity of the South American Monsoon System (SAMS) by means of Complex Networks. We first show how this approach leads to the identification of linkages between large-scale atmospheric conditions and natural hazards occurring at the earth's surface. Thereafter, we exemplify how our methodology can be used to compare different datasets and to test the performance of climate models. In recent years, complex networks have attracted great attention for analyzing the spatial characteristics of interrelations of various time series. Outstanding examples in this context are functional brain networks as well as so-called climate networks. In most approaches, the basic idea is to represent time series at different locations by network nodes, which will be connected by network links if the corresponding time series behave similar. Information on the spatial characteristics of these similarities can be inferred by network measures quantifying different aspects of the networks' topology. By combining several network measures and interpreting them in a climatic context, we investigate climatic linkages and classify the spatial characteristics of extreme rainfall synchronicity. Although our approach is based on only one variable (high spatiotemporal resolution rainfall), it reveals the most important features of the SAMS, such as the main moisture pathways, areas with frequent development of Mesoscale Convective Systems, and the major convergence zones. We will show that these features are only partially reproduced by reanalysis and (regional and global) climate model data.

  18. Tubulinosema pampeana sp. n. (Microsporidia, Tubulinosematidae), a pathogen of the South American bumble bee Bombus atratus.

    PubMed

    Plischuk, Santiago; Sanscrainte, Neil D; Becnel, James J; Estep, Alden S; Lange, Carlos E

    2015-03-01

    An undescribed microsporidium was detected and isolated from the South American bumble bee Bombus atratus collected in the Pampas region of Argentina. Infection intensity in workers averaged 8.2 × 10(7)spores/bee. The main site of infection was adipose tissue where hypertrophy of adipocytes resulted in cyst-like body formation. Mature spores were ovoid and monomorphic. They measured 4.00 μm × 2.37 μm (fresh) or 3.98 μm × 1.88 μm (fixed). All stages were diplokariotic and developed in direct contact with host cytoplasm. Isofilar polar filament was arranged in 16 coils in one or, posteriorly, two layers. Coiling angle was variable, between perpendicular and almost parallel to major spore axis. Late meronts and sporogonial stages were surrounded by vesicles of approximately 60 nm in diameter. Based on both new and already designed primers, a 1827 bp (SSUrRNA, ITS, LSUrRNA) sequence was obtained. Data analyses suggest that this microsporidium is a new species of the genus Tubulinosema. The name Tubulinosema pampeana sp. n. is proposed. PMID:25637516

  19. Patch network criteria for dispersal-limited endemic birds of South American temperate rain forest.

    PubMed

    Castellón, Traci D; Sieving, Kathryn E

    2007-12-01

    We developed a set of simple empirically based criteria for distinguishing forest patch configurations that we expected to support persistent populations of two endemic Tapaculo species with limited dispersal ability (Chucao Tapaculos [Scelorchilus rubecula] and Black-throated Huet-huets [Pteroptochos tarnii]) in South American temperate rain forest. The criteria address sustainable population sizes (tested using population viability analysis), habitat area needed to support sustainable populations, and measures of functional connectivity derived from radiotelemetry data and patch occupancy models. We then applied the criteria in three real-world demonstration landscapes, first, to predict numbers of breeding territories potentially accommodated within patch configurations and, second, to evaluate increases that might be achieved if landscape connections among isolated patches were restored (e.g., using corridors). The best connected of the three demonstration landscapes was predicted to support large sustainable populations without intervention to restore connectivity, whereas none of the patch configurations was sustainable in the most fragmented landscape, with or without corridor restoration. Notably, however, corridor restoration in the landscape with an intermediate fragmentation level was expected to quadruple the sustainable Chucao population and potentially prevent regional Huet-huet extinction. Thus, our network criteria provide a simple approach for developing and evaluating spatially explicit prescriptions for conservation planning in this highly endangered biome. The criteria may be especially useful for discriminating among landscapes where restoration of connectivity is, or is not, an appropriate course of action. PMID:18213959

  20. Comparison of precipitation datasets over the tropical South American and African Continents.

    NASA Astrophysics Data System (ADS)

    Negron-Juarez, R. I.; Li, W.; Fu, R.; Fernandes, K.; Cardoso, A.

    2007-12-01

    Six rainfall datasets are compared over the Amazon basin, the Northeast Brazil and the Congo basin. These datasets include three gauge-only precipitation products from the Climatic Prediction Center (CPC), Global Precipitation Climatology Center (GPCC) and Brazilian Weather Forecast and Climate Studies Center (CLMNLS), and three combined gauge and satellite precipitation datasets from the CPC Merged Analysis of Precipitation (CMAP), Global Precipitation Climatology Project (GPCP) precipitation, and Tropical Rainfall Measuring Mission (TRMM) product. The spatial pattern of the annual precipitation is consistently represented by these data, despite of the differences in methods and periods of averaging. Quantitatively, the differences in annual precipitation among these datasets are 3% over our Amazon domain (0-15S, 50-70W), 17% over the Northeast Brazil (5-10S, 35-45W) and 12% the Congo domain (5N-10S, 15-30E). However the seasonal differences were. Over the Amazon domain, the rainfall variations are well correlated between CPC, GPCC, TRMM, GPCP and GPCC (>0.9) except for the northwestern Amazon. Over the Congo basin, the correlation between these rainfall datasets is generally below 0.7. The Empirical Orthogonal Functions analysis suggests large discrepancies in interannual and decadal variations of rainfall among these datasets, especially for the Congo basin and for the South American region after 1998.

  1. Distribution of CGG repeats and FRAXAC1/DXS548 alleles in South American populations.

    PubMed

    Mingroni-Netto, Regina Célia; Angeli, Claudia B; Auricchio, Maria Teresa B M; Leal-Mesquita, Emygdia R; Ribeiro-dos-Santos, Andrea K C; Ferrari, Iris; Hutz, Mara H; Salzano, Francisco M; Hill, Kim; Hurtado, A Magdalena; Vianna-Morgante, Angela M

    2002-08-15

    In order to assess the molecular variability related to fragile X (FMR1 locus), we investigated the distribution of CGG repeats and DXS548/FRAXAC1 haplotypes in normal South American populations of different ethnic backgrounds. Special attention was given to Amerindian Wai-Wai (Northern Brazil) and Ache (Paraguay), as well as to Brazilian isolated communities of African ancestry, the remnants of quilombos. Comparison of samples from quilombos, Amerindians, and the ethnically mixed, but mainly European-derived population of São Paulo revealed that the 30-copy allele of the fragile X gene is the most frequent in all groups. A second peak at 20 repeats was present in the population of São Paulo only, confirming this as a European peculiarity. The distribution of DXS548 and FRAXAC1 alleles led to a high expected heterozygosity in African Brazilians, followed by that observed in the population of São Paulo. Amerindians showed the lowest diversity in CGG repeats and DXS548/FRAXAC1 haplotypes. Some rare alleles, for example, the 148-bp (FRAXAC1) or 200-bp (DXS548) variants, which seem to be almost absent in Europe, occurred in higher frequencies among African Brazilians. This suggests a general trend for higher genetic diversity among Africans; these rarer alleles could be African in origin and would have been lost or possibly were not present in the groups that gave rise to the Europeans. PMID:12210320

  2. Centennial-scale solar forcing of the South American Monsoon System recorded in stalagmites

    PubMed Central

    Novello, Valdir F.; Vuille, Mathias; Cruz, Francisco W.; Stríkis, Nicolás M.; de Paula, Marcos Saito; Edwards, R. Lawrence; Cheng, Hai; Karmann, Ivo; Jaqueto, Plínio F.; Trindade, Ricardo I. F.; Hartmann, Gelvam A.; Moquet, Jean S.

    2016-01-01

    The South American Monsoon System (SAMS) is generally considered to be highly sensitive to Northern Hemisphere (NH) temperature variations on multi-centennial timescales. The direct influence of solar forcing on moisture convergence in global monsoon systems on the other hand, while well explored in modeling studies, has hitherto not been documented in proxy data from the SAMS region. Hence little is known about the sensitivity of the SAMS to solar forcing over the past millennium and how it might compete or constructively interfere with NH temperature variations that occurred primarily in response to volcanic forcing. Here we present a new annually-resolved oxygen isotope record from a 1500-year long stalagmite recording past changes in precipitation in the hitherto unsampled core region of the SAMS. This record details how solar variability consistently modulated the strength of the SAMS on centennial time scales during the past 1500 years. Solar forcing, besides the previously recognized influence from NH temperature changes and associated Intertropical Convergence Zone (ITCZ) shifts, appears as a major driver affecting SAMS intensity at centennial time scales. PMID:27097590

  3. Overview of the South American biomass burning analysis (SAMBBA) field experiment

    NASA Astrophysics Data System (ADS)

    Morgan, W. T.; Allan, J. D.; Flynn, M.; Darbyshire, E.; Hodgson, A.; Johnson, B. T.; Haywood, J. M.; Freitas, S.; Longo, K.; Artaxo, P.; Coe, H.

    2013-05-01

    Biomass burning represents one of the largest sources of particulate matter to the atmosphere, which results in a significant perturbation to the Earth's radiative balance coupled with serious negative impacts on public health. Globally, biomass burning aerosols are thought to exert a small warming effect of 0.03 Wm-2, however the uncertainty is 4 times greater than the central estimate. On regional scales, the impact is substantially greater, particularly in areas such as the Amazon Basin where large, intense and frequent burning occurs on an annual basis for several months (usually from August-October). Furthermore, a growing number of people live within the Amazon region, which means that they are subject to the deleterious effects on their health from exposure to substantial volumes of polluted air. Initial results from the South American Biomass Burning Analysis (SAMBBA) field experiment, which took place during September and October 2012 over Brazil, are presented here. A suite of instrumentation was flown on-board the UK Facility for Airborne Atmospheric Measurement (FAAM) BAe-146 research aircraft and was supported by ground based measurements, with extensive measurements made in Porto Velho, Rondonia. The aircraft sampled a range of conditions with sampling of fresh biomass burning plumes, regional haze and elevated biomass burning layers within the free troposphere. The physical, chemical and optical properties of the aerosols across the region will be characterized in order to establish the impact of biomass burning on regional air quality, weather and climate.

  4. Continent-Wide Decoupling of Y-Chromosomal Genetic Variation from Language and Geography in Native South Americans

    PubMed Central

    Gusmão, Leonor; Gomes, Veronica; González, Miguel; Corach, Daniel; Sala, Andrea; Alechine, Evguenia; Palha, Teresinha; Santos, Ney; Ribeiro-dos-Santos, Andrea; Geppert, Maria; Willuweit, Sascha; Nagy, Marion; Zweynert, Sarah; Baeta, Miriam; Núñez, Carolina; Martínez-Jarreta, Begoña; González-Andrade, Fabricio; Fagundes de Carvalho, Elizeu; da Silva, Dayse Aparecida; Builes, Juan José; Turbón, Daniel; Lopez Parra, Ana Maria; Arroyo-Pardo, Eduardo; Toscanini, Ulises; Borjas, Lisbeth; Barletta, Claudia; Ewart, Elizabeth; Santos, Sidney; Krawczak, Michael

    2013-01-01

    Numerous studies of human populations in Europe and Asia have revealed a concordance between their extant genetic structure and the prevailing regional pattern of geography and language. For native South Americans, however, such evidence has been lacking so far. Therefore, we examined the relationship between Y-chromosomal genotype on the one hand, and male geographic origin and linguistic affiliation on the other, in the largest study of South American natives to date in terms of sampled individuals and populations. A total of 1,011 individuals, representing 50 tribal populations from 81 settlements, were genotyped for up to 17 short tandem repeat (STR) markers and 16 single nucleotide polymorphisms (Y-SNPs), the latter resolving phylogenetic lineages Q and C. Virtually no structure became apparent for the extant Y-chromosomal genetic variation of South American males that could sensibly be related to their inter-tribal geographic and linguistic relationships. This continent-wide decoupling is consistent with a rapid peopling of the continent followed by long periods of isolation in small groups. Furthermore, for the first time, we identified a distinct geographical cluster of Y-SNP lineages C-M217 (C3*) in South America. Such haplotypes are virtually absent from North and Central America, but occur at high frequency in Asia. Together with the locally confined Y-STR autocorrelation observed in our study as a whole, the available data therefore suggest a late introduction of C3* into South America no more than 6,000 years ago, perhaps via coastal or trans-Pacific routes. Extensive simulations revealed that the observed lack of haplogroup C3* among extant North and Central American natives is only compatible with low levels of migration between the ancestor populations of C3* carriers and non-carriers. In summary, our data highlight the fact that a pronounced correlation between genetic and geographic/cultural structure can only be expected under very specific

  5. In the Wake of Invasion: Tracing the Historical Biogeography of the South American Cricetid Radiation (Rodentia, Sigmodontinae)

    PubMed Central

    Leite, Rafael N.; Kolokotronis, Sergios-Orestis; Almeida, Francisca C.; Werneck, Fernanda P.; Rogers, Duke S.; Weksler, Marcelo

    2014-01-01

    The Great American Biotic Interchange (GABI) was greatly influenced by the completion of the Isthmus of Panama and impacted the composition of modern faunal assemblages in the Americas. However, the contribution of preceding events has been comparatively less explored, even though early immigrants in the fossil records are evidence for waif dispersals. The cricetid rodents of the subfamily Sigmodontinae are a classic example of a species-rich South American radiation resulting from an early episode of North American invasion. Here, we provide a temporal and spatial framework to address key aspects of the historical biogeography and diversification of this diverse mammal group by using mitochondrial and nuclear DNA datasets coupled with methods of divergence time estimation, ancestral area reconstruction and comparative phylogenetics. Relaxed-clock time estimates indicate that divergence of the Sigmodontinae began in the middle–late Miocene (ca. 12–9 Ma). Dispersal-vicariance analyses point to the arrival of a single lineage of northern invaders with a widespread ancestral distribution and imply that the initial differentiation between Central and South America gave rise to the most basal groups within the subfamily. These two major clades diversified in the late Miocene followed by the radiation of main tribes until the early Pliocene. Within the Oryzomyalia, tribes diverged initially in eastern South America whereas multiple dispersals into the Andes promoted further diversification of the majority of modern genera. A comparatively uniform background tempo of diversification explains the species richness of sigmodontines across most nodes, except for two akodontine genera with recent increases in diversification rates. The bridging of the Central American seaway and episodes of low sea levels likely facilitated the invasion of South America long before the onset of the post-Isthmian phase of the GABI. PMID:24963664

  6. In the wake of invasion: tracing the historical biogeography of the South American cricetid radiation (Rodentia, Sigmodontinae).

    PubMed

    Leite, Rafael N; Kolokotronis, Sergios-Orestis; Almeida, Francisca C; Werneck, Fernanda P; Rogers, Duke S; Weksler, Marcelo

    2014-01-01

    The Great American Biotic Interchange (GABI) was greatly influenced by the completion of the Isthmus of Panama and impacted the composition of modern faunal assemblages in the Americas. However, the contribution of preceding events has been comparatively less explored, even though early immigrants in the fossil records are evidence for waif dispersals. The cricetid rodents of the subfamily Sigmodontinae are a classic example of a species-rich South American radiation resulting from an early episode of North American invasion. Here, we provide a temporal and spatial framework to address key aspects of the historical biogeography and diversification of this diverse mammal group by using mitochondrial and nuclear DNA datasets coupled with methods of divergence time estimation, ancestral area reconstruction and comparative phylogenetics. Relaxed-clock time estimates indicate that divergence of the Sigmodontinae began in the middle-late Miocene (ca. 12-9 Ma). Dispersal-vicariance analyses point to the arrival of a single lineage of northern invaders with a widespread ancestral distribution and imply that the initial differentiation between Central and South America gave rise to the most basal groups within the subfamily. These two major clades diversified in the late Miocene followed by the radiation of main tribes until the early Pliocene. Within the Oryzomyalia, tribes diverged initially in eastern South America whereas multiple dispersals into the Andes promoted further diversification of the majority of modern genera. A comparatively uniform background tempo of diversification explains the species richness of sigmodontines across most nodes, except for two akodontine genera with recent increases in diversification rates. The bridging of the Central American seaway and episodes of low sea levels likely facilitated the invasion of South America long before the onset of the post-Isthmian phase of the GABI. PMID:24963664

  7. Convergence and contingency in production-precipitation relationships in North American and South African C4 grasslands.

    PubMed

    Knapp, Alan K; Burns, Catherine E; Fynn, Richard W S; Kirkman, Kevin P; Morris, Craig D; Smith, Melinda D

    2006-09-01

    Mesic grasslands in North America and South Africa share many structural attributes, but less is known of their functional similarities. We assessed the control of a key ecosystem process, aboveground net primary production (ANPP), by interannual variation in precipitation amount and pattern via analysis of data sets (15- and 24-year periods) from long-term research programs on each continent. Both sites were dominated by C(4) grasses and had similar growing season climates; thus, we expected convergence in precipitation-ANPP relationships. Lack of convergence, however, would support an alternative hypothesis-that differences in evolutionary history and purportedly greater climatic variability in South Africa fundamentally alter the functioning of southern versus northern hemisphere grasslands. Neither mean annual precipitation nor mean ANPP differed between the South African and North American sites (838 vs. 857 mm/year, 423.5 vs. 461.4 g/m(2) respectively) and growing season precipitation-ANPP relationships were similar. Despite overall convergence, there were differences between sites in how the seasonal timing of precipitation affected ANPP. In particular, interannual variability in precipitation that fell during the first half of the growing season strongly affected annual ANPP in South Africa (P < 0.01), but was not related to ANPP in North America (P = 0.098). Both sites were affected similarly by late season precipitation. Divergence in the seasonal course of available soil moisture (chronically low in the winter and early spring in the South African site vs. high in the North American site) is proposed as a key contingent factor explaining differential sensitivity in ANPP to early season precipitation in these two grasslands. These long-term data sets provided no support for greater rainfall, temperature or ANPP variability in the South African versus the North American site. However, greater sensitivity of ANPP to early season precipitation in the South

  8. High-resolution Holocene South American monsoon history recorded by a speleothem from Botuverá Cave, Brazil

    NASA Astrophysics Data System (ADS)

    Bernal, J. P.; Cruz, Francisco W.; Stríkis, Nicolás M.; Wang, Xianfeng; Deininger, Michael; Catunda, Maria Carolina A.; Ortega-Obregón, C.; Cheng, Hai; Edwards, R. Lawrence; Auler, Augusto S.

    2016-09-01

    A Holocene stalagmite from Botuverá Cave, southeastern Brazil was analyzed by LA-ICPMS for Mg/Ca, Sr/Ca, Ba/Ca. The observed variability in the record was demonstrated to be modulated by prior calcite precipitation, and, thus, is interpreted to reflect monsoon intensity. We find that the calcite δ18O is strongly correlated with Sr/Ca, indicating that atmospheric circulation over South America and monsoon intensity have been tightly correlated throughout most of the Holocene, both directly responding to solar precession. Comparison with other contemporaneous high-resolution hydroclimate records reveals that SAMS has shown a degree of complexity during the Holocene not previously detected, with periods where the South American Convergence Zone (SACZ) expanded to cover most of the South American sub-continent, and coincident with periods of low-SST in the north Atlantic. We also detect periods where rainfall amount in northeastern and southeastern Brazil are markedly anti-phased, suggesting a north-south migration of SACZ, which it appears to be mediated by solar irradiance. The high-resolution nature of our record allow us to examine the effect that Holocene climate anomalies had upon SAMS dynamics and hydroclimate in southeastern Brazil, in particular the 8.2 ka event and the Little Ice Age. In addition to confirm the internal structure of the events, we also detect the possible consequences of the climatic anomalies upon ocean-atmosphere interactions through its effects upon SAMS.

  9. A new phylogeny for basal Trechnotheria and Cladotheria and affinities of South American endemic Late Cretaceous mammals.

    PubMed

    Averianov, Alexander O; Martin, Thomas; Lopatin, Alexey V

    2013-04-01

    The endemic South American mammals Meridiolestida, considered previously as dryolestoid cladotherians, are found to be non-cladotherian trechnotherians related to spalacotheriid symmetrodontans based on a parsimony analysis of 137 morphological characters among 44 taxa. Spalacotheriidae is the sister taxon to Meridiolestida, and the latter clade is derived from a primitive spalacolestine that migrated to South America from North America at the beginning of the Late Cretaceous. Meridiolestida survived until the early Paleocene (Peligrotherium) and early Miocene (Necrolestes) in South America, and their extinction is probably linked to the increasing competition with metatherian and eutherian tribosphenic mammals. The clade Meridiolestida plus Spalacotheriidae is the sister taxon to Cladotheria and forms a new clade Alethinotheria. Alethinotheria and its sister taxon Zhangheotheria, new clade (Zhangheotheriidae plus basal taxa), comprise Trechnotheria. Cladotheria is divided into Zatheria (plus stem taxa, including Amphitherium) and Dryolestida, including Dryolestidae and a paraphyletic array of basal dryolestidans (formerly classified as "Paurodontidae"). The South American Vincelestes and Groebertherium are basal dryolestidans. PMID:23494201

  10. Final Gondwana breakup: The Paleogene South American native ungulates and the demise of the South America-Antarctica land connection

    NASA Astrophysics Data System (ADS)

    Reguero, Marcelo A.; Gelfo, Javier N.; López, Guillermo M.; Bond, Mariano; Abello, Alejandra; Santillana, Sergio N.; Marenssi, Sergio A.

    2014-12-01

    The biogeographic hypothesis more accepted today is that Antarctica (West Antarctica) and southern South America (Magellan region, Patagonia) were connected by a long and narrow causeway (Weddellian Isthmus) between the Antarctic Peninsula and South America since the Late Cretaceous (Campanian) until the Early Paleogene allowing terrestrial vertebrates to colonize new frontiers using this land bridge. Stratigraphically calibrated phylogenies including large, terrestrial native ungulates Litopterna and Astrapotheria taxa reveal long ghost lineages that extended into the Late Paleocene and provide evidence for the minimum times at which these "native ungulates" were present both on Antarctica and South America. Based on these results we estimate that the Weddellian Isthmus was functional as a land bridge until the Late Paleocene. Our data place the disconnection between Antarctica and South America in the Late Paleocene, indicating that the terrestrial faunistic isolation (Simpson's "splendid isolation") in South America begun at the end of the Paleocene (~ 56 to 57 m.y.). This faunistic isolation is documented to have occurred at least 25 Ma before the existence of deep-water circulation conditions in Drake Passage (~ 30 m.y.) based on the onset of seafloor spreading in the west Scotia Sea region. We hypothesize that in the early stages of extension (Late Paleocene, ~ 55 m.y.) a wide and relatively shallow epicontinental sea developed between the Antarctic Peninsula and South America drowning the Weddellian Isthmus and preventing the faunal interchange for obligate cursorial terrestrial forms.

  11. Perspectives of South American physicians hosting foreign rotators in emergency medicine

    PubMed Central

    2014-01-01

    Background Emergency Medicine (EM) is increasingly becoming an international field. The number of fellowships in International EM in the USA is growing along with opportunities to complete international health electives (IHEs) during residency training. The impact on host institutions, however, has not been adequately investigated. The objective of this study is to assess the experience of several South American hospitals hosting foreign EM residents completing IHEs. Methods Anonymous, semi-structured one-on-one interviews were conducted with physicians working in Emergency Departments in three hospitals in Lima, Peru and one hospital in Buenos Aires, Argentina. All participants reported previously working with EM foreign rotators. Interviews were analyzed qualitatively and coded for common themes. Results Three department chairs, six residents, and 15 attending physicians were interviewed (total = 24). After qualitative analysis of interviews, two broad theme categories emerged: Benefits and Challenges. Most commonly reported benefits were knowledge sharing about emergency medical systems (78%), medical knowledge transfer (58%), and long-term relationship formation (42%). Top challenges included rotator Spanish language proficiency (70%) lack of reciprocity (58%), and level of training and rotation length (25%). Spanish proficiency related directly to how involved rotators became in patient care (e.g., taking a history, participating in rounds) but was not completely prohibitive, as a majority of physicians interviewed felt comfortable speaking in English. Lack of reciprocity refers to the difficulty of sending host physicians abroad as well as failed attempts at building long-lasting relationships with foreign institutions. Lastly, 25% preferred rotators to stay for at least 1 month and rotate in the last year of EM residency. This latter preference increased knowledge transfer from rotator to host. Conclusions Our research identified benefits and challenges

  12. Lithospheric structure beneath the Caribbean- South American plate boundary from S receiver functions

    NASA Astrophysics Data System (ADS)

    Masy, J.; Levander, A.; Niu, F.

    2010-12-01

    We have analyzed teleseismic S-wave data recorded by the permanent national seismic network of Venezuela and the BOLIVAR broadband array (Broadband Onshore-offshore Lithospheric Investigation of Venezuela and the Antilles arc Region) deployed from 2003 to 2005. A total of 28 events with Mw > 5.7 occurring at epicentral distances from 55° to 85° were used. We made Sp receiver functions to estimate the rapid variations of lithospheric structure in the southern Caribbean plate boundary region to try to better understand the complicated tectonic history of the region. Estimated Moho depth ranges from ~20 km beneath the Caribbean Large Igneous Provinces to ~50 km beneath the Mérida Andes in western Venezuela and the Sierra del Interior in northeastern Venezuela. These results are consistent with previous receiver functions studies (Niu et al., 2007) and active source profiles (Schmitz et al., 2001; Bezada et al., 2007; Clark et al., 2008; Guedez, 2008; Magnani et al., 2009). Beneath the Maracaibo Block we observe a signal at a depth of 100 km dipping ~24° towards the continent, which we interpret as the top of the oceanic Caribbean slab that is subducting beneath South America from the west. The deeper part of the slab was previously imaged using P-wave tomography (Bezada et al, 2010), and the upper part inferred from intermediate depth seismicity (Malavé and Suarez, 1995). These studies indicate flat slab subduction beneath northern Colombia and northwestern Venezuela with the slab dipping between 20° - 30° beneath Lake Maracaibo. Like others we attribute the flat slab subduction to the uplift of the Mérida Andes (for example Kellogg and Bonini, 1982). In eastern Venezuela beneath the Sierra del Interior we also observe a deep signal that we interpret as deep South American lithosphere that is detaching from the overriding plate as the Atlantic subducts and tears away from SA (Bezada et al., 2010; Clark et al, 2008). The lithosphere-asthenosphere boundary (LAB

  13. What Works? A Qualitative Examination of the Factors Related to the Academic Success of African American Males at a Predominantly White College in the South

    ERIC Educational Resources Information Center

    Robertson, Ray V.; Mason, Danielle

    2008-01-01

    Our study examined the factors related to the retention/academic success of African American males at a mid-sized, regional, predominantly white university in the south. The selected university has an African American male graduation rate, of approximately twenty three percent, which is thirteen percentage points below the national Black male…

  14. Standing on a Strong Foundation of Servitude: The 1960's Civil Rights Movement, Septima Clark and Other South Carolina African American Women Educators

    ERIC Educational Resources Information Center

    Hunter, Iris Renell

    2012-01-01

    This research study examines nine African American women educators during the 1960s Civil Rights Movement in South Carolina. Additionally, the study conducts an analogous study of the lifeworks and contributions of Septima Clark, an African American woman educator who made significant community activist contributions during this period. For its…

  15. Ultraviolet radiation-induced skin tumors in a South American opossum (Monodelphis domestica).

    PubMed

    Kusewitt, D F; Applegate, L A; Ley, R D

    1991-01-01

    A total of 19 male and 21 female South American opossums (Monodelphis domestica) were exposed to 250 J/m2 ultraviolet radiation from FS-40 sunlamps (280-400 nm) three times weekly for 70 weeks. The backs of the opossums were shaved as necessary to remove hair. In order to prevent photoreactivation of ultraviolet radiation-induced pyrimidine dimers by the light-dependent photolyase enzyme of the opossum, ultraviolet radiation-exposed opossums were housed under red lights (600-800 nm). The opossum photolyase requires light in the 320-450 nm range for its activity. Twenty-nine control opossums (14 males and 15 females) were irradiated by fluorescent lights with emission spectra primarily in the visible light range (320-700 nm); these control opossums were also housed under red lights, and their backs were also shaved to remove hair. No skin tumors were observed in control opossums, while ultraviolet radiation-exposed opossums developed a variety of hyperplastic and neoplastic skin lesions on the backs and on a single ear. Hyperplastic lesions included foci of epithelial hyperplasia, dermal fibroplasia, and focal proliferation of dermal melanocytes. A total of 20 ultraviolet radiation-exposed opossums (50%) developed skin tumors, and 13 opossums (32.5%) had more than a single tumor. Epithelial tumors included 25 papillomas, four keratoacanthomas, seven carcinomas in situ, three microinvasive squamous cell carcinomas, two invasive squamous cell carcinomas, and a single basal cell tumor. Ten dermal spindle cell tumors also occurred; most of these appeared to be fibrosarcomas. Two benign melanomas and one malignant melanoma were observed. PMID:2017828

  16. Convergent evolution of alternative developmental trajectories associated with diapause in African and South American killifish

    PubMed Central

    Furness, Andrew I.; Reznick, David N.; Springer, Mark S.; Meredith, Robert W.

    2015-01-01

    Annual killifish adapted to life in seasonally ephemeral water-bodies exhibit desiccation resistant eggs that can undergo diapause, a period of developmental arrest, enabling them to traverse the otherwise inhospitable dry season. Environmental cues that potentially indicate the season can govern whether eggs enter a stage of diapause mid-way through development or skip this diapause and instead undergo direct development. We report, based on construction of a supermatrix phylogenetic tree of the order Cyprinodontiformes and a battery of comparative analyses, that the ability to produce diapause eggs evolved independently at least six times within African and South American killifish. We then show in species representative of these lineages that embryos entering diapause display significant reduction in development of the cranial region and circulatory system relative to direct-developing embryos. This divergence along alternative developmental pathways begins mid-way through development, well before diapause is entered, during a period of purported maximum developmental constraint (the phylotypic period). Finally, we show that entering diapause is accompanied by a dramatic reduction in metabolic rate and concomitant increase in long-term embryo survival. Morphological divergence during the phylotypic period thus allows embryos undergoing diapause to conserve energy by shunting resources away from energetically costly organs thereby increasing survival chances in an environment that necessitates remaining dormant, buried in the soil and surrounded by an eggshell for much of the year. Our results indicate that adaptation to seasonal aquatic environments in annual killifish imposes strong selection during the embryo stage leading to marked diversification during this otherwise conserved period of vertebrate development. PMID:25631993

  17. Schmallenberg virus infection in South American camelids: Field and experimental investigations.

    PubMed

    Schulz, Claudia; Beer, Martin; Hoffmann, Bernd

    2015-11-18

    During the first epizootic wave of the novel, teratogenic Schmallenberg virus (SBV, Orthobunyavirus) in ruminants in Northern Europe, serological evidence of a previous SBV-infection demonstrated that South American camelids (SAC) are also susceptible to SBV. However, their potential role in SBV spread remains unknown. To investigate the prevalence and course of SBV-infection in SAC, a German field study and an animal trial with three llamas and three alpacas were conducted. From September 2012 to December 2013, 313 of 502 SAC (62.35%) were found SBV seropositive, but negative for SBV-RNA. The estimated between-district (94.23% of 52) and median within-district (71.43%) and herd (73.13%) SBV seroprevalence in German SAC was similar to the seroprevalence reported in cattle herds and sheep flocks at the time. An age of >1 year was found a statistically significant risk factor for SBV-infection, which could be explained by the spatio-temporal spread of SBV in Germany during the study period. No clinical signs or an increase of abortion and congenital malformation associated with SBV-infection in SAC were reported by the study participants. Similar to SBV-infected ruminants, SBV-RNAemia in experimentally SBV-infected SAC was detected for a short time between days 3 and 7 after infection (dpi), and seroconversion occurred between 9 and 21 dpi. Despite the similar virological and serological results, the lack of clinical signs and congenital malformation associated with SBV-infection suggests that SBV causes subclinical infection in SAC. However, their role as reservoirs in the spread of SBV has to be further investigated. PMID:26361966

  18. The Thermoregulatory Function of Thatched Nests in the South American Grass-Cutting Ant, Acromyrmex heyeri

    PubMed Central

    Bollazzi, Martin; Roces, Flavio

    2010-01-01

    The construction of mound-shaped nests by ants is considered as a behavioral adaptation to low environmental temperatures, i.e., colonies achieve higher and more stables temperatures than those of the environment. Besides the well-known nests of boreal Formica wood-ants, several species of South American leaf-cutting ants of the genus Acromyrmex construct thatched nests. Acromyrmex workers import plant fragments as building material, and arrange them so as to form a thatch covering a central chamber, where the fungus garden is located. Thus, the degree of thermoregulation attained by the fungus garden inside the thatched nest largely depends on how the thatch affects the thermal relations between the fungus and the environment. This work was aimed at studying the thermoregulatory function of the thatched nests built by the grass-cutting ant Acromyrmex heyeri Forel (Hymenoptera: Formicidae: Myrmicinae). Nest and environmental temperatures were measured as a function of solar radiation on the long-term. The thermal diffusivity of the nest thatch was measured and compared to that of the surrounding soil, in order to assess the influence of the building material on the nest's thermoregulatory ability. The results showed that the average core temperature of thatched nests was higher than that of the environment, but remained below values harmful for the fungus. This thermoregulation was brought about by the low thermal diffusivity of the nest thatch built by workers with plant fragments, instead of the readily-available soil particles that have a higher thermal diffusivity. The thatch prevented diurnal nest overheating by the incoming solar radiation, and avoided losses of the accumulated daily heat into the cold air during the night. The adaptive value of thatching behavior in Acromyrmex leaf-cutting ants occurring in the southernmost distribution range is discussed. PMID:20883129

  19. Convergent evolution of alternative developmental trajectories associated with diapause in African and South American killifish.

    PubMed

    Furness, Andrew I; Reznick, David N; Springer, Mark S; Meredith, Robert W

    2015-03-01

    Annual killifish adapted to life in seasonally ephemeral water-bodies exhibit desiccation resistant eggs that can undergo diapause, a period of developmental arrest, enabling them to traverse the otherwise inhospitable dry season. Environmental cues that potentially indicate the season can govern whether eggs enter a stage of diapause mid-way through development or skip this diapause and instead undergo direct development. We report, based on construction of a supermatrix phylogenetic tree of the order Cyprinodontiformes and a battery of comparative analyses, that the ability to produce diapause eggs evolved independently at least six times within African and South American killifish. We then show in species representative of these lineages that embryos entering diapause display significant reduction in development of the cranial region and circulatory system relative to direct-developing embryos. This divergence along alternative developmental pathways begins mid-way through development, well before diapause is entered, during a period of purported maximum developmental constraint (the phylotypic period). Finally, we show that entering diapause is accompanied by a dramatic reduction in metabolic rate and concomitant increase in long-term embryo survival. Morphological divergence during the phylotypic period thus allows embryos undergoing diapause to conserve energy by shunting resources away from energetically costly organs thereby increasing survival chances in an environment that necessitates remaining dormant, buried in the soil and surrounded by an eggshell for much of the year. Our results indicate that adaptation to seasonal aquatic environments in annual killifish imposes strong selection during the embryo stage leading to marked diversification during this otherwise conserved period of vertebrate development. PMID:25631993

  20. Pattern recognition method applied to the forecast of strong earthquakes in South American seismic prone areas

    SciTech Connect

    Benavidez, A.

    1986-01-01

    The pattern recognition method is applied to the Andean seismic region that extends from southern latitudes 2 to 27 in the South American continent, to set a criterion for the prediction of the potential sites of strong earthquakes epicenters in the zone. It is assumed that two hypothesis hold. First, the strong earthquake epicenters typically cluster around the intersection of morphostructural lineaments. Second, the rules of recognition obtained for neighboring zones which exhibit distinctive neotectonic evolution, state of stress, spatial earthquake distribution and geological development, may be different in spite of the fact that the morphostructural zoning does not reflect a separation between them. Hence, the region is divided into two broad-scale tectonic segments located above slabs of similar scale in the Nazca plate in which subduction takes place almost subhorizontally (dipping at an angle of about 10) between latitudes 2S and 15S, and at a steeper angle (of approximately 30) within latitudes 15S to 27S. The morphostructural zoning is carried out for both zones with the determination of the lineaments and the corresponding disjunctive knots which are defined as the objects of recognition when applying the pattern recognition method. The Cora-3 algorithm is used as the computational procedure for the search of the rule of recognition of dangerous and non-dangerous sites for each zone. The set criteria contain in each case several characteristic features that represent the topography, geology and tectonics of each region. Also, it is shown that they have a physical meaning that mostly reflects the style of tectonic deformation in the related regions.

  1. Microbial diversity in European and South American spacecraft assembly clean rooms

    NASA Astrophysics Data System (ADS)

    Moissl-Eichinger, Christine; Stieglmeier, Michaela; Schwendner, Petra

    Spacecraft assembly clean rooms are unique environments for microbes: Due to low nutri-ent levels, desiccated, clean conditions, constant control of humidity and temperature, these environments are quite inhospitable to microbial life and even considered "extreme". Many procedures keep the contamination as low as possible, but these conditions are also highly se-lective for indigenous microbial communities. For space missions under planetary protection requirements, it is crucial to control the contaminating bioburden as much as possible; but for the development of novel cleaning/sterilization methods it is also important to identify and characterize (understand) the present microbial community of spacecraft clean rooms. In prepa-ration for the recently approved ESA ExoMars mission, two European and one South American spacecraft assembly clean rooms were analyzed with respect to their microbial diversity, using standard procedures, new cultivation approaches and molecular methods, that should shed light onto the presence of planetary protection relevant microorganisms. For this study, the Her-schel Space Observatory (launched in May 2009) and its housing clean rooms in Friedrichshafen (Germany), at ESTEC (The Netherlands) and CSG, Kourou (French Guyana) were sampled during assembly, test and launch operations. Although Herschel does not demand planetary protection requirements, all clean rooms were in a fully operating state during sampling. This gave us the opportunity to sample the microbial diversity under strict particulate and molecular contamination-control. Samples were collected from spacecraft and selected clean room surface areas and were subjected to cultivation assays (32 different media), molecular studies (based on 16S rRNA gene sequence analysis) and quantitative PCR. The results from different strategies will be compared and critically discussed, showing the advantages and limits of the selected methodologies. This talk will sum up the lessons

  2. Disease and Development: Evidence from Hookworm Eradication in the American South*

    PubMed Central

    Bleakley, Hoyt

    2013-01-01

    This study evaluates the economic consequences of the successful eradication of hookworm disease from the American South. The hookworm-eradication campaign (c. 1910) began soon after (i) the discovery that a variety of health problems among Southerners could be attributed to the disease and (ii) the donation by John D. Rockefeller of a substantial sum to the effort. The Rockefeller Sanitary Commission (RSC) surveyed infection rates in the affected areas (eleven southern states) and found that an average of forty percent of school-aged children were infected with hookworm. The RSC then sponsored treatment and education campaigns across the region. Follow-up studies indicate that this campaign substantially reduced hookworm disease almost immediately. The sudden introduction of this treatment combines with the cross-area differences in pre-treatment infection rates to form the basis of the identification strategy. Areas with higher levels of hookworm infection prior to the RSC experienced greater increases in school enrollment, attendance, and literacy after the intervention. This result is robust to controlling for a variety of alternative factors, including differential trends across areas, changing crop prices, shifts in certain educational and health policies, and the effect of malaria eradication. No significant contemporaneous results are found for adults, who should have benefited less from the intervention owing to their substantially lower (prior) infection rates. A long-term follow-up of affected cohorts indicates a substantial gain in income that coincided with exposure to hookworm eradication. I also find evidence that eradication increased the return to schooling. PMID:24146438

  3. Computed tomographic and radiographic examination of dental structures in South American camelid specimen of different ages

    PubMed Central

    2014-01-01

    Background Tooth root problems and periodontal diseases are common in South American camelids (SAC). The objective was to evaluate and optimize the imaging technique for dental radiography in SAC and to describe the radiographic and computed tomographic (CT) anatomy of normal teeth at different ages. In this study, the heads of 20 healthy SAC slaughtered for meat production or euthanized for reasons not related to dental problems included 7 female and 10 male llamas and 3 male alpacas. Using a standardized protocol, radiographs and CT scans of the 20 specimen were performed. Results The most useful radiographic projections for mandibular and maxillary cheek teeth evaluation turned out to be lateral30°ventral - laterodorsal and lateral30°dorsal - lateroventral with slight separation of the dental arcades respectively. Digital radiographic and CT appearance of the mandibular and maxillary teeth were described from the beginning of mineralization till maturity. In addition the normal range of the CT radio density of different cheek teeth and different dental tissues were measured. Hounsfield units of different dental tissues of SAC turned out to be similar to equids. Deviation, shortening and partial destruction of the distal tooth root of mandibular 09′s and 10′s and of maxillary 09′s was observed and the existence of a common pulp chamber in younger teeth was revealed. Conclusions The present study provides information about the dental imaging morphology in clinically healthy SAC. This basic information provides fundamental knowledge for evaluating images and planning treatments in clinically affected animals. PMID:24393365

  4. Efficacy of anthelmintics on South American camelid (llama and alpaca) farms in Georgia.

    PubMed

    Gillespie, Rose-Ann M; Williamson, Lisa H; Terrill, Thomas H; Kaplan, Ray M

    2010-08-27

    The number of South American camelid (SAC; llama and alpaca) farms is growing in the southeastern United States, and infection with gastrointestinal nematodes (GIN) is a major health concern in this region. There is widespread resistance to anthelmintic remedies in small ruminants (sheep and goats), but a paucity of information on llamas and alpacas. Anthelmintic resistance was evaluated on three SAC farms (two llama; one alpaca) in Georgia in the southern United States using fecal egg count reduction (FECR) tests. For each farm, animals were randomly assigned to 1 of 5 treatment groups based on initial fecal egg count (FEC) and number of animals available (2-5 groups, n=9-11 per treatment). Ivermectin (IVM, subcutaneous injection; 0.3mg/kg body weight (BW)) and a control group were tested on an alpaca farm, and fenbendazole (FBZ, oral; 10mg/kg BW; two farms), moxidectin (MOX oral; 0.2mg/kg BW; two farms), and levamisole (LEV, oral; 8 mg/kg BW; one farm) were added for the llama farms. Anthelmintic efficacy was determined by comparing FEC of treatment and control animals 14 days post-treatment, with resistance evaluated using the World Association for the Advancement of Veterinary Parasitology (WAAVP) guidelines. Based upon these guidelines, there was GIN resistance to IVM in both llamas and alpacas in Georgia and to FBZ on both llama farms where this drug was tested. There was MOX resistance on one llama farm using the FECR test, while there was no resistance to LEV detected in this study. These data demonstrate a serious emerging problem in the United States of llama and alpaca GIN resistant to drugs from two of the three major anthelmintic classes. PMID:20462700

  5. Disease and Development: Evidence from Hookworm Eradication in the American South.

    PubMed

    Bleakley, Hoyt

    2007-01-01

    This study evaluates the economic consequences of the successful eradication of hookworm disease from the American South. The hookworm-eradication campaign (c. 1910) began soon after (i) the discovery that a variety of health problems among Southerners could be attributed to the disease and (ii) the donation by John D. Rockefeller of a substantial sum to the effort. The Rockefeller Sanitary Commission (RSC) surveyed infection rates in the affected areas (eleven southern states) and found that an average of forty percent of school-aged children were infected with hookworm. The RSC then sponsored treatment and education campaigns across the region. Follow-up studies indicate that this campaign substantially reduced hookworm disease almost immediately. The sudden introduction of this treatment combines with the cross-area differences in pre-treatment infection rates to form the basis of the identification strategy. Areas with higher levels of hookworm infection prior to the RSC experienced greater increases in school enrollment, attendance, and literacy after the intervention. This result is robust to controlling for a variety of alternative factors, including differential trends across areas, changing crop prices, shifts in certain educational and health policies, and the effect of malaria eradication. No significant contemporaneous results are found for adults, who should have benefited less from the intervention owing to their substantially lower (prior) infection rates. A long-term follow-up of affected cohorts indicates a substantial gain in income that coincided with exposure to hookworm eradication. I also find evidence that eradication increased the return to schooling. PMID:24146438

  6. South by Southwest: Mexican Americans and Segregated Schooling, 1900-1950.

    ERIC Educational Resources Information Center

    Ruiz, Vicki L.

    2001-01-01

    Addresses school segregation and Mexican Americans, delineating the institutional nature of segregation "for the cause of Americanization." Discusses "Alvarez v. Lemon Grove School District" and "Mendez v. Westminster," two important legal challenges by Mexican American parents on behalf of their children. Includes a bibliography. (CMK)

  7. "The South American Way": Hollywood Looks at Latins and at Latin America.

    ERIC Educational Resources Information Center

    Aiex, Nola Kortner

    Latin elements or themes made for the North American market have been used in American films, but at the same time these films have been playing in a Latin American market, making it useful to examine how Latin America has been portrayed in these films. The taste for exotic locales and themes is an element that has been present since the…

  8. Reaching into the Digital Divide: Technological Use of Computers by African American Male Youth in the American South

    ERIC Educational Resources Information Center

    Moore, Antionette L.

    2012-01-01

    The purpose of this qualitative study was to explore how the computer is utilized in the daily lives of seven African American male youth in the southeastern region of the United States. Critical pedagogy was selected as the theoretical framework using Paulo Freire ideas of problem-posing education to promote awareness towards using the computer…

  9. Coalescent Simulation and Paleodistribution Modeling for Tabebuia rosealba Do Not Support South American Dry Forest Refugia Hypothesis.

    PubMed

    de Melo, Warita Alves; Lima-Ribeiro, Matheus S; Terribile, Levi Carina; Collevatti, Rosane G

    2016-01-01

    Studies based on contemporary plant occurrences and pollen fossil records have proposed that the current disjunct distribution of seasonally dry tropical forests (SDTFs) across South America is the result of fragmentation of a formerly widespread and continuously distributed dry forest during the arid climatic conditions associated with the Last Glacial Maximum (LGM), which is known as the modern-day dry forest refugia hypothesis. We studied the demographic history of Tabebuia rosealba (Bignoniaceae) to understand the disjunct geographic distribution of South American SDTFs based on statistical phylogeography and ecological niche modeling (ENM). We specifically tested the dry forest refugia hypothesis; i.e., if the multiple and isolated patches of SDTFs are current climatic relicts of a widespread and continuously distributed dry forest during the LGM. We sampled 235 individuals across 18 populations in Central Brazil and analyzed the polymorphisms at chloroplast (trnS-trnG, psbA-trnH and ycf6-trnC intergenic spacers) and nuclear (ITS nrDNA) genomes. We performed coalescence simulations of alternative hypotheses under demographic expectations from two a priori biogeographic hypotheses (1. the Pleistocene Arc hypothesis and, 2. a range shift to Amazon Basin) and other two demographic expectances predicted by ENMs (3. expansion throughout the Neotropical South America, including Amazon Basin, and 4. retraction during the LGM). Phylogenetic analyses based on median-joining network showed haplotype sharing among populations with evidence of incomplete lineage sorting. Coalescent analyses showed smaller effective population sizes for T. roseoalba during the LGM compared to the present-day. Simulations and ENM also showed that its current spatial pattern of genetic diversity is most likely due to a scenario of range retraction during the LGM instead of the fragmentation from a once extensive and largely contiguous SDTF across South America, not supporting the South

  10. Coalescent Simulation and Paleodistribution Modeling for Tabebuia rosealba Do Not Support South American Dry Forest Refugia Hypothesis

    PubMed Central

    de Melo, Warita Alves; Lima-Ribeiro, Matheus S.; Terribile, Levi Carina

    2016-01-01

    Studies based on contemporary plant occurrences and pollen fossil records have proposed that the current disjunct distribution of seasonally dry tropical forests (SDTFs) across South America is the result of fragmentation of a formerly widespread and continuously distributed dry forest during the arid climatic conditions associated with the Last Glacial Maximum (LGM), which is known as the modern-day dry forest refugia hypothesis. We studied the demographic history of Tabebuia rosealba (Bignoniaceae) to understand the disjunct geographic distribution of South American SDTFs based on statistical phylogeography and ecological niche modeling (ENM). We specifically tested the dry forest refugia hypothesis; i.e., if the multiple and isolated patches of SDTFs are current climatic relicts of a widespread and continuously distributed dry forest during the LGM. We sampled 235 individuals across 18 populations in Central Brazil and analyzed the polymorphisms at chloroplast (trnS-trnG, psbA-trnH and ycf6-trnC intergenic spacers) and nuclear (ITS nrDNA) genomes. We performed coalescence simulations of alternative hypotheses under demographic expectations from two a priori biogeographic hypotheses (1. the Pleistocene Arc hypothesis and, 2. a range shift to Amazon Basin) and other two demographic expectances predicted by ENMs (3. expansion throughout the Neotropical South America, including Amazon Basin, and 4. retraction during the LGM). Phylogenetic analyses based on median-joining network showed haplotype sharing among populations with evidence of incomplete lineage sorting. Coalescent analyses showed smaller effective population sizes for T. roseoalba during the LGM compared to the present-day. Simulations and ENM also showed that its current spatial pattern of genetic diversity is most likely due to a scenario of range retraction during the LGM instead of the fragmentation from a once extensive and largely contiguous SDTF across South America, not supporting the South

  11. Is the genetic structure of Gran Chaco populations unique? Interregional perspectives on native South American mitochondrial DNA variation.

    PubMed

    Cabana, Graciela S; Merriwether, D Andrew; Hunley, Keith; Demarchi, Darío A

    2006-09-01

    This study reevaluates the hypothesis in Demarchi et al. (2001 Am. J. Phys. Anthropol. 115:199-203) that Gran Chaco peoples demonstrate a unique pattern of genetic diversity due to a distinct regional population history. Specifically, they found populations in the central part of the Gran Chaco, or Central Chaco, to have higher within- and lower between-population mitochondrial DNA (mtDNA) haplogroup frequency variation compared to populations in other South American regions. To test this hypothesis of regional uniqueness, we applied analytical and simulation methods to mtDNA first hypervariable (HVI) region sequence data from a broad set of comparative South and Central American population samples. Contrary to the results of Demarchi et al. (2001 Am. J. Phys. Anthropol. 115:199-203), we found that the Gran Chaco's regional within-population diversity is about average among regions, and populations are highly differentiated from each other. When we limited the scale of analysis to the Central Chaco, a more localized subregion of the Gran Chaco, our results fell more in line with the original findings of Demarchi et al. (2001 Am. J. Phys. Anthropol. 115:199-203). Still, we conclude that neither the Gran Chaco regional pattern, nor the Central Chaco subregional pattern, is unique within South America. Nonetheless, the Central Chaco pattern accords well with the area's history, including pre-European contact lifeways and the documented historical use of the area as an interregional crossroads. However, we cannot exclude post-European contact disruption of traditional mating networks as an equally plausible explanation for the observed diversity pattern. Finally, these results additionally inform broader models of South American genetic diversity. While other researchers proposed an east-west continental division in patterns of genetic variation (e.g., Fuselli et al. 2003 Mol. Biol. Evol. 20:1682-1691), we found that in the geographically intermediate Central Chaco, a

  12. Dinosaur Speed Demon: The Caudal Musculature of Carnotaurus sastrei and Implications for the Evolution of South American Abelisaurids

    PubMed Central

    Persons, W. Scott; Currie, Philip J.

    2011-01-01

    In the South American abelisaurids Carnotaurus sastrei, Aucasaurus garridoi, and, to a lesser extent Skorpiovenator bustingorryi, the anterior caudal ribs project at a high dorsolateral inclination and have interlocking lateral tips. This unique morphology facilitated the expansion of the caudal hypaxial musculature at the expense of the epaxial musculature. Distinct ridges on the ventrolateral surfaces of the caudal ribs of Aucasaurus garridoi are interpreted as attachment scars from the intra caudofemoralis/ilio-ischiocaudalis septa, and confirm that the M. caudofemoralis of advanced South American abelisaurids originated from a portion of the caudal ribs. Digital muscle models indicate that, relative to its overall body size, Carnotaurus sastrei had a substantially larger M. caudofemoralis than any other theropod yet studied. In most non-avian theropods, as in many extant sauropsids, the M. caudofemoralis served as the primary femoral retractor muscle during the locomotive power stroke. This large investment in the M. caudofemoralis suggests that Carnotaurus sastrei had the potential for great cursorial abilities, particularly short-burst sprinting. However, the tightly interlocking morphology of the anterior caudal vertebrae implies a reduced ability to make tight turns. Examination of these vertebral traits in evolutionary context reveals a progressive sequence of increasing caudofemoral mass and tail rigidity among the Abelisauridae of South America. PMID:22043292

  13. The phylogeography of trypanosomes from South American alligatorids and African crocodilids is consistent with the geological history of South American river basins and the transoceanic dispersal of Crocodylus at the Miocene

    PubMed Central

    2013-01-01

    Background Little is known about the diversity, phylogenetic relationships, and biogeography of trypanosomes infecting non-mammalian hosts. In this study, we investigated the influence of host species and biogeography on shaping the genetic diversity, phylogenetic relationship, and distribution of trypanosomes from South American alligatorids and African crocodilids. Methods Small Subunit rRNA (SSU rRNA) and glycosomal Glyceraldehyde Phosphate Dehydrogenase (gGAPDH) genes were employed for phylogenetic inferences. Trypanosomes from crocodilians were obtained by haemoculturing. Growth behaviour, morphology, and ultrastructural features complement the molecular description of two new species strongly supported by phylogenetic analyses. Results The inferred phylogenies disclosed a strongly supported crocodilian-restricted clade comprising three subclades. The subclade T. grayi comprised the African Trypanosoma grayi from Crocodylus niloticus and tsetse flies. The subclade T. ralphi comprised alligatorid trypanosomes represented by Trypanosoma ralphi n. sp. from Melanosuchus niger, Caiman crocodilus and Caiman yacare from Brazilian river basins. T. grayi and T. ralphi were sister subclades. The basal subclade T. terena comprised alligatorid trypanosomes represented by Trypanosoma terena n. sp. from Ca. yacare sharing hosts and basins with the distantly genetic related T. ralphi. This subclade also included the trypanosome from Ca. crocodilus from the Orinoco basin in Venezuela and, unexpectedly, a trypanosome from the African crocodilian Osteolaemus tetraspis. Conclusion The close relationship between South American and African trypanosomes is consistent with paleontological evidence of recent transoceanic dispersal of Crocodylus at the Miocene/Pliocene boundaries (4–5 mya), and host-switching of trypanosomes throughout the geological configuration of South American hydrographical basins shaping the evolutionary histories of the crocodilians and their trypanosomes

  14. "She Told Them, Oh That Bitch Got AIDS": Experiences of Multilevel HIV/AIDS-Related Stigma Among African American Women Living with HIV/AIDS in the South.

    PubMed

    Fletcher, Faith; Ingram, Lucy Annang; Kerr, Jelani; Buchberg, Meredith; Bogdan-Lovis, Libby; Philpott-Jones, Sean

    2016-07-01

    African American women bear a disproportionate burden of HIV/AIDS in the United States. Although they constitute only 13% of the US population, African Americans account for nearly 65% of all new HIV infections among American women. In addition, this population suffers comparatively greater adverse health outcomes related to HIV status. African American women living with HIV in the South may be further burdened by HIV/AIDS stigma, which is comparatively more pronounced in this region. To further explore this burden, we used narrative data and the Social Ecological Model to explore how African American women living with HIV in the US South recount, conceptualize, and cope with HIV/AIDS stigma at interpersonal, community, and institutional levels. Our narrative analysis suggests that HIV-positive African American women living in the South are vulnerable to experiences of multilevel HIV stigma in various settings and contexts across multiple domains of life. Stigma subsequently complicated disclosure decisions and made it difficult for women to feel supported in particular social, professional and medical settings that are generally regarded as safe spaces for noninfected individuals. Findings suggest that the debilitating and compounded effect of multilevel HIV/AIDS stigma on HIV-positive African American women in the South warrants closer examination to tailor approaches that effectively address the unique needs of this population. PMID:27410498

  15. Ground-based aerosol characterization during the South American Biomass Burning Analysis (SAMBBA) field experiment

    NASA Astrophysics Data System (ADS)

    Brito, J.; Rizzo, L. V.; Morgan, W. T.; Coe, H.; Johnson, B.; Haywood, J.; Longo, K.; Freitas, S.; Andreae, M. O.; Artaxo, P.

    2014-11-01

    This paper investigates the physical and chemical characteristics of aerosols at ground level at a site heavily impacted by biomass burning. The site is located near Porto Velho, Rondônia, in the southwestern part of the Brazilian Amazon rainforest, and was selected for the deployment of a large suite of instruments, among them an Aerosol Chemical Speciation Monitor. Our measurements were made during the South American Biomass Burning Analysis (SAMBBA) field experiment, which consisted of a combination of aircraft and ground-based measurements over Brazil, aimed to investigate the impacts of biomass burning emissions on climate, air quality, and numerical weather prediction over South America. The campaign took place during the dry season and the transition to the wet season in September/October 2012. During most of the campaign, the site was impacted by regional biomass burning pollution (average CO mixing ratio of 0.6 ppm), occasionally superimposed by intense (up to 2 ppm of CO), freshly emitted biomass burning plumes. Aerosol number concentrations ranged from ~1000 cm-3 to peaks of up to 35 000 cm-3 (during biomass burning (BB) events, corresponding to an average submicron mass mean concentrations of 13.7 μg m-3 and peak concentrations close to 100 μg m-3. Organic aerosol strongly dominated the submicron non-refractory composition, with an average concentration of 11.4 μg m-3. The inorganic species, NH4, SO4, NO3, and Cl, were observed, on average, at concentrations of 0.44, 0.34, 0.19, and 0.01 μg m-3, respectively. Equivalent black carbon (BCe) ranged from 0.2 to 5.5 μg m-3, with an average concentration of 1.3 μg m-3. During BB peaks, organics accounted for over 90% of total mass (submicron non-refractory plus BCe), among the highest values described in the literature. We examined the ageing of biomass burning organic aerosol (BBOA) using the changes in the H : C and O : C ratios, and found that throughout most of the aerosol processing (O : C &cong

  16. Ground based aerosol characterization during the South American Biomass Burning Analysis (SAMBBA) field experiment

    NASA Astrophysics Data System (ADS)

    Brito, J.; Rizzo, L. V.; Morgan, W. T.; Coe, H.; Johnson, B.; Haywood, J.; Longo, K.; Freitas, S.; Andreae, M. O.; Artaxo, P.

    2014-05-01

    This paper investigates the physical and chemical characteristics of aerosols at ground level at a site heavily impacted by biomass burning. The site is located near Porto Velho, Rondônia, in the Southwestern part of the Brazilian Amazon forest, and was selected for the deployment of a large suite of instruments, among them an Aerosol Chemical Speciation Monitor. Our measurements were made during the South American Biomass Burning Analysis (SAMBBA) field experiment, which consisted of a combination of aircraft and ground based measurements over Brazil, aiming to investigate the impacts of biomass burning emissions on climate, air quality, and numerical weather prediction over South America. The campaign took place during the dry season and the transition to the wet season in September/October 2012. During most of the campaign, the site was impacted by regional biomass burning pollution (average CO mixing ratio of 0.6 ppm), occasionally superimposed by intense (up to 2 ppm of CO), freshly emitted biomass burning plumes. Aerosol number concentrations ranged from ∼1000 cm-3 to peaks of up to 35 000 cm-3 during biomass burning (BB) events, corresponding to an average submicron mass mean concentrations of 13.7 μg m-3 and peak concentrations close to 100 μg m-3. Organic aerosol strongly dominated the submicron non-refractory composition, with an average concentration of 11.4 μg m-3. The inorganic species, NH4, SO4, NO3, and Cl, were observed on average at concentrations of 0.44, 0.34, 0.19, and 0.01 μg m-3, respectively. Equivalent Black Carbon (BCe) ranged from 0.2 to 5.5 μg m-3, with an average concentration of 1.3 μg m-3. During BB peaks, organics accounted for over 90% of total mass (submicron non-refractory plus BCe), among the highest values described in the literature. We examined the ageing of Biomass Burning Organic Aerosol (BBOA) using the changes in the H : C and O : C ratios, and found that throughout most of the aerosol processing (O : C ≅ 0

  17. A taxonomic revision of South American species of the seed-harvester ant genus Pogonomyrmex (Hymenoptera: Formicidae). Part I.

    PubMed

    Johnson, Robert A

    2015-01-01

    South American species in the seed-harvester ant genus Pogonomyrmex (subfamily Myrmicinae) are interesting biologically because of their numerous queen phenotypes and life histories. This paper provides a taxonomic revision and reviews the natural history for 21 South American species of Pogonomyrmex so that we can better study their rich and interesting ecology, life history, and evolution. Species treated herein comprise all South American species-groups except for the brevibarbis and rastratus-groups. The following taxa are raised to species: pencosensis Forel 1914 and serpens Santschi 1922. The following new synonomies are proposed: bruchi Forel 1913 is synonomized under coarctatus Mayr 1868 and cunicularius carnivora Santschi 1925 under serpens Santschi 1922. The following new species is described: tinogasta. This paper redescribes workers of all species, and I describe queens and diagnose males for the following species: bispinosus (ergatoid queen, male), inermis (queen, male), laticeps (male), lobatus (queen, male), micans (queen), naegelii (ergatoid queen), pencosensis (ergatoid queen), serpens (ergatoid queen), tinogasta (brachypterous queen), and uruguayensis (queen, male). A neotype was designated for the untraceable or possibly lost type of P. bispinosus, and a holotype or lectotype was designated from syntypes for all other previously described taxa in order to provide a single name-bearing specimen and to facilitate future taxonomic studies. Of the 21 species treated herein, five species have ergatoid (wingless) queens (bispinosus, cunicularius, pencosensis, serpens, mayri), two have brachypterous (short-winged) queens (mendozanus, tinogasta), and two have dimorphic queens (winged and ergatoid in naegelii, brachypterous and ergatoid in laticeps). I also provide keys for workers and queens (in English and Spanish), photographs of all castes, distribution maps, and a summary of known biology. PMID:26624334

  18. Neoproterozoic evolution of the basement of the South-American platform

    NASA Astrophysics Data System (ADS)

    de Brito Neves, Benjamim Bley; Fuck, Reinhardt A.

    2013-11-01

    Neoproterozoic geologic and geotectonic processes were of utmost importance in forming and structuring the basement framework of the South-American platform. Two large domains with distinct evolutionary histories are identified with respect to the Neoproterozoic era: the northwest-west (Amazonian craton and surroundings) and the central-southeast (the extra-Amazonian domain). In the first domain, Neoproterozoic events occurred only locally and were of secondary significance, and the geologic events, processes, and structures of the pre-Neoproterozoic (and syn-Brasiliano) cratonic block were much more influential. In the second, the extra-Amazonian domain, the final evolution, structures and forms are assigned to events related to the development of a complex net of Neoproterozoic mobile belts. These in turn resulted in strong reworking of the older pre-Neoproterozoic basement. In this domain, four distinct structural provinces circumscribe or are separated by relatively small pre-Neoproterozoic cratonic nuclei, namely the Pampean, Tocantins, Borborema and Mantiqueira provinces. These extra-Amazonian provinces were formed by a complex framework of orogenic branching systems following a diversified post-Mesoproterozoic paleogeographic scenario. This scenario included many types of basement inliers as well as a diversified organization of accretionary and collisional orogens. The basement inliers date from the Archean to Mesoproterozoic periods and are different in nature. The escape tectonics that operated during the final consolidation stages of the provinces were important to and responsible for the final forms currently observed. These latest events, which occurred from the Late Ediacaran to the Early Ordovician, present serious obstacles to paleogeographic reconstructions. Two groups of orogenic collage systems are identified. The older system from the Tonian (>850 Ma) period is of restricted occurrence and is not fully understood due to strong reworking

  19. Holocene tropical South American hydroclimate revealed from a decadally resolved lake sediment δ 18O record

    NASA Astrophysics Data System (ADS)

    Bird, Broxton W.; Abbott, Mark B.; Rodbell, Donald T.; Vuille, Mathias

    2011-10-01

    Oxygen isotope ratios of authigenic calcite (δ 18O cal) measured at annual to decadal resolution from Laguna Pumacocha document Andean precipitation variability during the last 11,200 years. Modern limnological data show that Pumacocha δ 18O cal reflects the average annual isotopic composition of the lake's surface waters (δ 18O lw), and that δ 18O lw tracks the isotopic composition of precipitation (δ 18O precip), which is largely controlled by the intensity of the South American summer monsoon (SASM). Based on these relationships we use down-core δ 18O cal measurements as a proxy for δ 18O precip that varies with the intensity of SASM precipitation. Pumacocha δ 18O cal increased rapidly between 11,200 and 10,300 yr B.P. from - 14.5‰ to - 10.5‰, reaching a maximum of - 10.3‰ by 9800 yr B.P. After 9800 yr B.P., δ 18O cal underwent a long-term decrease that tracked increasing Southern Hemisphere summer insolation, suggesting that enhanced SASM precipitation was linked to precessional forcing. Higher-frequency trends did not follow insolation and therefore represent other variability in the climate system. Millennial-scale trends from Pumacocha strongly resemble those from lower-resolution tropical Andean ice and lake core isotopic records, particularly the Huascaran ice core, and low elevation speleothems. These relationships suggest that tropical Andean isotopic records reflect variations in precipitation intensity related to precessional forcing rather than tropical temperatures. They also demonstrate a coherent pattern of SASM variability, although with differences between low elevation and Andean records during the late Glacial to Holocene transition and the late Holocene. Centennial and decadal SASM precipitation variability is also apparent. Reduced SASM rainfall occurred from 10,000-9200, 7000-5000, 1500-900 yr B.P. and during the last 100 years. Intensifications of the SASM occurred at 5000, 2200-1500, and 550-130 yr B.P. with the amplitude of

  20. More cultivation with lower intensity in the South American Chaco: A double hydrological challenge

    NASA Astrophysics Data System (ADS)

    Jobbagy, E. G.; Gimenez, R.; Mercau, J. L.; Houspanossian, J.; Baldi, G.; Kuppel, S.

    2014-12-01

    As in other semi-arid plains of the world, long-scale deforestation to establish croplands in the South American Chaco may disrupt the regional water balance. As annual crops use less water than the native perennial system, water in excess usually translates into serious degradation processes such as run-off driven erosion, or the onset of groundwater recharge which can develop flooding and dryland salinization. Agriculturally, water excess could be reduced by using more intensive crop systems which consume water exhaustively. We used MODIS imagery (2000-present) from Bandera, Argentina (28.8S 62.2W), a major agricultural cluster in the region, to assess deforestation, to identify the main crop systems, and to analyze the impact of crop expansion and phenological shifts on the regional water balance. Three cover classes (Dry Forest DF, Agriculture AG, and Pastures PA) and five AG crop types were distinguished (winter W, spring Sp,summer S, and late-summer LS single crops, winter/summer DCWS and spring/summer DCSpS double crops). Each season, water use (annual evapotranspiration, ET) for each cover/crop type (10 pixels/class) was computed with a daily water balance based on meteorological data and 2 remote sensing-derived indices: Normalized Difference Vegetation Index, to capture canopy conditions, and Dead Fuel Index to represent mulch cover conditions. Throughout 14 crop seasons AG expanded from 20 to 50% of the study area (1M ha) mostly replacing DF. Also, AG gradually evolved from a more intensive and diversified pattern dominated by DC (45-50%), S (28%) and Sp (16%) systems, to a more water-conservative system dominated by LS (60-80% in the last 3 seasons). Crop type differences in ET (DCWS≈DCSpS≈FG>S>Sp>LS≈W) were stronger in wet years (>1000mm) but nil in dry ones (<550mm). As a result, water excess (precipitation-ET) ranged from 0mm for most crop types in the driest year to >250mm for the less intensive W and LS in wet years. Weighting each cover

  1. Two new and two redescribed species of Anonchotaenia (Cestoda: Paruterinidae) from South American birds.

    PubMed

    Phillips, Anna J; Georgiev, Boyko B; Waeschenbach, Andrea; Mariaux, Jean

    2014-10-01

    several species of different passerine families that participate in mixed-species foraging flocks in the Atlantic Forest. A diversity of species of other families join these flocks and are among the substantial number of South American passerine species yet to be examined for cestodes. PMID:25549500

  2. Male courtship behavior of the South American fruit fly, Anastrepha fraterculus, from an Argentinean laboratory strain.

    PubMed

    Gomez Cendra, P; Calcagno, G; Belluscio, L; Vilardi, J C

    2011-01-01

    The South American fruit fly Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) is a pest of fruit species of warm regions of the Americas, including Argentina. Some authors claim that this taxon includes a group of cryptic species. In order to evaluate possible targets of sexual selection, it is necessary to analyze ethological aspects of male courtship and identify particular steps that strongly influence mating success. A mating test designed to evaluate behavioral differences between insects that achieve copulation (successful males) and those that did not mate (unsuccessful males) could also be relevant for the possible implementation of control programs based on sterile insect technique. Reared insects need to be evaluated periodically, since genetic drift and artificial selection associated with rearing conditions could have a detrimental effect on their ability to compete for matings in nature. In this study, courtship behavior of A. fraterculus males from a laboratory strain was analyzed for the first time through video recordings. Three components for the activities were identified: calling, wing positions, and movements. Also, the time that males spent on each step of the courtship was registered, including the last activities before attempting copulation. Data showed that mating achievement occurs relatively quickly; 65% of the successful males reached copulation within the first ten minutes after the male and female were placed together. Behavioral differences were detected between successful and unsuccessful males. The former group tended to invest more time in activities directly related with mating (Spin, Arrowhead, Attempt); however, as courtship progressed, unsuccessful males increased the time dedicated to activities not directly associated to mating (Call 0, Relax,Stationary). There was not a single sequence of activities leading to success, but the analysis of the last activities performed before mating attempts indicated that the most

  3. Comparing Terrestrial Organic Carbon Cycle Dynamics in Interglacial and Glacial Climates in the South American Tropics

    NASA Astrophysics Data System (ADS)

    Fornace, K. L.; Galy, V.; Hughen, K. A.

    2014-12-01

    The application of compound-specific radiocarbon dating to molecular biomarkers has allowed for tracking of specific organic carbon pools as they move through the environment, providing insight into complex processes within the global carbon cycle. Here we use this technique to investigate links between glacial-interglacial climate change and terrestrial organic carbon cycling in the catchments of Cariaco Basin and Lake Titicaca, two tropical South American sites with well-characterized climate histories since the last glacial period. By comparing radiocarbon ages of terrestrial biomarkers (leaf wax compounds) with deposition ages in late glacial and Holocene sediments, we are able to gauge the storage time of these compounds in the catchments in soils, floodplains, etc. before transport to marine or lacustrine sediments. We are also able to probe the effects of temperature and hydrologic change individually by taking advantage of opposite hydrologic trends at the two sites: while both were colder during the last glacial period, precipitation at Titicaca decreased from the last glacial period to the Holocene, but the late glacial was marked by drier conditions at Cariaco. Preliminary data from both sites show a wide range of apparent ages of long-chain n-fatty acids (within error of 0 to >10,000 years older than sediment), with the majority showing ages on the order of several millennia at time of deposition and age generally increasing with chain length. While late glacial leaf waxes appear to be older relative to sediment than those deposited in the Holocene at both sites, at Cariaco we find a ~2-3 times larger glacial-interglacial age difference than at Titicaca. We hypothesize that at Titicaca the competing influences of wetter and colder conditions during the last glacial period, which respectively tend to increase and decrease the rate of organic carbon turnover on land, served to minimize the contrast between glacial and interglacial leaf wax storage time

  4. Silent Endurance and Profound Loneliness: Socioemotional Suffering in African Americans Living With HIV in the Rural South

    PubMed Central

    Miles, Margaret Shandor; Isler, Malika Roman; Banks, Bahby B.; Sengupta, Sohini; Corbie-Smith, Giselle

    2011-01-01

    We explored how community responses to HIV contribute to distress in African Americans living with HIV in the rural South of the United States. We listened to the voices of community members through focus groups and African Americans with HIV through interviews. Community avoidance of HIV, negative views of HIV, and discriminatory behavior powerfully affected the distress of people living with HIV (PLWH). Ongoing distress, coupled with limited support, led to a life in which many PLWH endured their pain in silence and experienced profound loneliness. We conceptualized their experiences as socioemotional suffering—the hidden emotional burden and inner distress of not only living with HIV, a complex serious illness, but also with the societal attitudes and behaviors that are imposed on the illness and on PLWH. To improve the quality of life and health of PLWH, we cannot focus solely on the individual, but must also focus on the local community and society as a whole. PMID:21041516

  5. Archeomagnetism of Jesuit Missions in South Brazil (1657-1706 AD) and assessment of the South American database

    NASA Astrophysics Data System (ADS)

    Poletti, Wilbor; Trindade, Ricardo I. F.; Hartmann, Gelvam A.; Damiani, Nadir; Rech, Raquel M.

    2016-07-01

    South America contributes only a small fraction of the global archeomagnetic data. Recent work in the region has expanded significantly the previous database with new data being generated from Chile, Argentina, Northeast and Southeast Brazil. We report here new results from Jesuit Missions in South Brazil, at the triple border with Argentina and Paraguay. Our archeological collection comprises a total of 24 fragments of baked clay construction materials from three Jesuit Missions, São Luiz Gonzaga 1657-1687 AD (3 fragments), São João Batista 1667-1697 AD (4 fragments) and Santo Ângelo 1676-1706 AD (17 fragments). Archeointensity determinations were performed with the double-heating technique in its modified form, with pTRM checks and pTRM tail checks. Measurements were complemented by anisotropy and cooling-rate corrections. A total of 24 specimens (11 fragments) passed strict quality selection, corresponding to a success rate of 45%. We also performed an experimental test for the 6-specimen average anisotropy correction technique and we show that it does not correct for the effects of TRM anisotropy. Results were similar within error for the three missions: São Luiz Gonzaga (40.2 ± 2.4 μT), São João Batista (39.1 ± 1.6 μT) and Santo Ângelo (41.1 ± 2.0 μT). These data were then compared with the most reliable data from South America, after a critical assessment of the current database. According to our analysis, only 39 intensity data for the continent can be considered as high-quality, most within the last 700 years; only three data were retained for older periods (800-1100 AD). The filtered data match reasonably well the available models for the past five centuries. A combined curve for South and Southeast Brazil plus Argentina plot systematically below relocated data from NE Brazil and Chile. These differences are likely due to complexities in the geometry of the field in South America not appropriately accounted for by a simple axial dipole. Our

  6. First Chemical Analysis and Characterization of the Male Species-Specific Cephalic Labial-Gland Secretions of South American Bumblebees.

    PubMed

    Brasero, Nicolas; Martinet, Baptiste; Urbanová, Klára; Valterová, Irena; Torres, Alexandra; Hoffmann, Wolfgang; Rasmont, Pierre; Lecocq, Thomas

    2015-10-01

    The evolution of signals and reproductive traits involved in the pre-mating recognition has been in focus of abundant research in several model species, such as bumblebees (genus Bombus). However, the most-studied bumblebee reproductive trait, the male cephalic labial gland secretions (CLGS), remains unknown among bumblebee species from South America. In this study, the CLGS of five South American bumblebees of the subgenera Thoracobombus (Bombus excellens and B. atratus) and Cullumanobombus (B. rubicundus, B. hortulanus, and B. melaleucus) were investigated, by comparing the chemical compositions of their secretions to those of closely related European species. The results showed an obvious interspecific differentiation in both subgenera. The interspecific differentiation among the species of the Thoracobombus subgenus involved different compounds present at high contents (main compounds), while those of the Cullumanobombus subgenus shared the same main components. This suggests that among the species of the Cullumanobombus subgenus, the differentiation in minor components could lead to species discrimination. PMID:26460558

  7. 10-Methyldodecanal, a Novel Attractant Pheromone Produced by Males of the South American Cerambycid Beetle Eburodacrys vittata.

    PubMed

    Silva, Weliton D; Millar, Jocelyn G; Hanks, Lawrence M; Bento, José Maurício S

    2016-01-01

    We report the identification, synthesis, and field bioassay of a novel attractant pheromone produced by males of Eburodacrys vittata (Blanchard), a South American cerambycid beetle in the subfamily Cerambycinae. Headspace volatiles from males contained a sex-specific compound, identified as 10-methyldodecanal. In a field bioassay conducted in Brazil, significant numbers of males and females were caught in traps baited with synthesized racemic 10-methyldodecanal, consistent with the aggregation-sex pheromones produced by males of many cerambycine species. This compound represents a new structural class of cerambycid pheromones, and it is the first pheromone identified for a species in the tribe Eburiini. PMID:27512985

  8. 10-Methyldodecanal, a Novel Attractant Pheromone Produced by Males of the South American Cerambycid Beetle Eburodacrys vittata

    PubMed Central

    Millar, Jocelyn G.; Hanks, Lawrence M.; Bento, José Maurício S.

    2016-01-01

    We report the identification, synthesis, and field bioassay of a novel attractant pheromone produced by males of Eburodacrys vittata (Blanchard), a South American cerambycid beetle in the subfamily Cerambycinae. Headspace volatiles from males contained a sex-specific compound, identified as 10-methyldodecanal. In a field bioassay conducted in Brazil, significant numbers of males and females were caught in traps baited with synthesized racemic 10-methyldodecanal, consistent with the aggregation-sex pheromones produced by males of many cerambycine species. This compound represents a new structural class of cerambycid pheromones, and it is the first pheromone identified for a species in the tribe Eburiini. PMID:27512985

  9. Avian Schistosomes from the South American Endemic Gastropod Genus Chilina (Pulmonata: Chilinidae), with a Brief Review of South American Schistosome Species.

    PubMed

    Flores, Verónica; Brant, Sara V; Loker, Eric S

    2015-10-01

    Our current knowledge of avian schistosomes from South America is scarce in all respects, including species and generic diversity, their life cycles, patterns of host use, potential to cause dermatitis outbreaks, and evolutionary affinities. As a step towards addressing this shortcoming, the goal of this study was to provide discrete reference points relating to snail hosts, locality records, morphological attributes, sequence for nuclear 28S and ITS, and partial mitochondrial cox1 genes, and phylogenetic relationships for schistosome cercariae recovered from different species of Chilina, which are gastropods endemic to South America. In total, 1,308 snails belonging to 6 species of Chilina were collected from 12 localities across Argentina. Thirty-eight snails (2.9%) had schistosome infections. Our data indicate the presence of 3 lineages of Chilina-transmitted schistosomes, all of which group within the major avian schistosome clade. However, none of the lineages grouped within or as sister to other known avian schistosome genera in the tree, indicating they probably represent undescribed genera. The relationships of these schistosomes from Chilina spp. are discussed in relation to their position in the global schistosome phylogenetic tree. PMID:26186680

  10. A proof of concept study to assess the potential of PCR testing to detect natural Mycobacterium bovis infection in South American camelids

    PubMed Central

    2014-01-01

    Background Cases of Mycobacterium bovis infection South American camelids have been increasing in Great Britain. Current antemortem immunological tests have some limitations. Cases at post mortem examination frequently show extensive pathology. The feasibility of detecting Mycobacterium bovis DNA in clinical samples was investigated. Findings A sensitive extraction methodology was developed and used on nasal swabs and faeces taken post-mortem to assess the potential for a PCR test to detect Mycobacterium bovis in clinical samples. The gross pathology of the studied South American camelids was scored and a significantly greater proportion of South American camelids with more severe pathology were positive in both the nasal swab and faecal PCR tests. A combination of the nasal swab and faecal PCR tests detected 63.9% of all the South American camelids with pathology that were tested. Conclusions The results suggest that antemortem diagnosis of Mycobacterium bovis in South American camelids may be possible using a PCR test on clinical samples, however more work is required to determine sensitivity and specificity, and the practicalities of applying the test in the field. PMID:24507471

  11. How Amazonian deforestation can alter the South American circulation regime: Insights from a non-linear moisture transport model

    NASA Astrophysics Data System (ADS)

    Boers, Niklas; Marwan, Norbert; Barbosa, Henrique; Kurths, Jürgen

    2015-04-01

    A key driver of South American climate are the low-level trade winds from the tropical Atlantic Ocean towards the continent. After crossing the Amazon Basin, they are blocked by the Andes mountain range, and forced southward to the subtropics. These winds are crucial for the atmospheric moisture supply in most parts of South America. In particular, the hydrology of the two largest river basins of the Continent, namely the Amazon and the La Plata Basins, strongly depend on the moisture inflow provided by the trade winds. In turn, the Amazon rainforest can be assumed to have a strong influence on this low-level moisture circulation over South America by exchanging moisture with the atmosphere through precipitation and evapotranspiration. A pronounced positive feedback in this context is established through precipitation-induced release of latent heat over the Amazon Basin, which significantly enhances the moisture inflow from the tropical Atlantic Ocean toward the continent and can thus be considered to be crucial for the existence of today's South American climate. Ongoing deforestation and resulting reduction in evapotranspiration rates in particular in the eastern Amazon carry the risk of a strongly nonlinear response in these interactions with the low-level atmosphere. We propose a simple differential transport model describing the cascading moisture transport from the eastern coast of South America across the Amazon Basin to the Andes, taking into account the nonlinearity associated with the release of latent heat. The results of the model suggest that the system is indeed very sensitive to relatively small reductions of the evapotranspiration rates in the eastern Amazon Basin. These reductions increase river runoff, but limit the moisture availability farther west. This leads to a reduction in precipitation rates and thereby diminishes the release of latent heat which, in turn, reduces the overall moisture inflow. We show that, according to our model, there

  12. Healthcare reconsidered: forging community wellness among African Americans in the south.

    PubMed

    Nelson, Jennifer

    2007-01-01

    This article details the history of Slossfield Hospital, an African American hospital and community center founded in Birmingham, Alabama, in 1937. During its New Deal-era existence it provided African American physicians institutional support for their medical practices. Additionally, as a community center, it addressed the socioeconomics of good health. This paper uses Slossfield as a case study to explore how some African Americans included the socioeconomic in their definition of public health during the New Deal, as well as to understand how these ideas were subsumed by more mainstream ideas about public health promulgated by black and white physicians and the local and federal governments. PMID:17873453

  13. Characterization of an unidentified Sarcocystis falcatula-like parasite from the South American opossum, Didelphis albiventris from Brazil.

    PubMed

    Dubey, J P; Lindsay, D S; Rezende, P C; Costa, A J

    2000-01-01

    An unidentified isolate of a Sarcocystis falcatula-like parasite was obtained from the lungs of budgerigars (Melopsittacus undulatus) fed sporocysts from a naturally-infected South American opossum, Didelphis albiventris from Brazil. Four captive budgerigars fed sporocysts from the opossum intestine died of acute sarcocystosis 8, 10, and 12 days after oral inoculation (DAI); one budgerigar was killed 12 DAI when it was lethargic. Schizonts and merozoites found in the lungs of the budgerigars reacted mildly with polyclonal S. falcatula antibody. The parasite was isolated in equine kidney cell cultures inoculated with lung tissue from a budgerigar that was killed 12 DAI. Two budgerigars inoculated subcutaneously with 100,000 culture-derived S. falcatula merozoites developed acute sarcocystosis and S. falcatula-like schizonts were found in their lungs 15 and 16 DAI. Four budgerigars kept as unfed controls in the same environment remained free of Sarcocystis infection. The parasite underwent schizogony in African green monkey kidney cells and bovine turbinate cells. Merozoites divided by endopolygeny, often leaving a residual body. Polymerase chain reaction studies using primers JNB33/JNB54 and Hinf I and Dra I digestion indicated that the isolate was not S. falcatula. Results of this study indicated that the South American opossum, D. albiventris, is a definitive host for yet another S. falcatula-like parasite. PMID:11128705

  14. Inclusion of South American samples reveals new population structuring of the blacktip shark (Carcharhinus limbatus) in the western Atlantic.

    PubMed

    Sodré, Davidson; Rodrigues-Filho, Luis F S; Souza, Rosália F C; Rêgo, Péricles S; Schneider, Horacio; Sampaio, Iracilda; Vallinoto, Marcelo

    2012-12-01

    Carcharhinus limbatus has a cosmopolitan distribution and marked genetic structuring, mainly because of its philopatric behavior. However, analysis of this structuring has not previously included South American populations. In the present study, we analyzed a sample of adult individuals collected on the northern coast of Brazil and compared the sequences of the mitochondrial control region with those of populations already genotyped. Relatively high haplotype diversity (12 haplotypes, genetic diversity of 0.796) was observed, similar to that in other populations but with a much larger number of private alleles. In contrast to populations studied previously, which were represented by neonates, the pronounced allelic variability found in the South American individuals may have resulted from migrations from other populations in the region that have yet to be genotyped. This population was also genetically distinct from the other Atlantic populations (F(st) > 0.8), probably because of female philopatry, and apparently separated from the northwestern Atlantic group 1.39 million years ago. These findings indicate that the C. limbatus population from northern Brazil is genetically distinct from all other populations and should be considered as a different management unit for the protection of stocks. PMID:23271935

  15. First record of Wolbachia in South American terrestrial isopods: Prevalence and diversity in two species of Balloniscus (Crustacea, Oniscidea)

    PubMed Central

    Almerão, Mauricio Pereira; Fagundes, Nelson Jurandi Rosa; de Araújo, Paula Beatriz; Verne, Sébastien; Grandjean, Frédéric; Bouchon, Didier; Araújo, Aldo Mellender

    2012-01-01

    Wolbachia are endosymbiotic bacteria that commonly infect arthropods, inducing certain phenotypes in their hosts. So far, no endemic South American species of terrestrial isopods have been investigated for Wolbachia infection. In this work, populations from two species of Balloniscus (B. sellowii and B. glaber) were studied through a diagnostic PCR assay. Fifteen new Wolbachia 16S rDNA sequences were detected. Wolbachia found in both species were generally specific to one population, and five populations hosted two different Wolbachia 16S rDNA sequences. Prevalence was higher in B. glaber than in B. sellowii, but uninfected populations could be found in both species. Wolbachia strains from B. sellowii had a higher genetic variation than those isolated from B. glaber. AMOVA analyses showed that most of the genetic variance was distributed among populations of each species rather than between species, and the phylogenetic analysis suggested that Wolbachia strains from Balloniscus cluster within Supergroup B, but do not form a single monophyletic clade, suggesting multiple infections for this group. Our results highlight the importance of studying Wolbachia prevalence and genetic diversity in Neotropical species and suggest that South American arthropods may harbor a great number of diverse strains, providing an interesting model to investigate the evolution of Wolbachia and its hosts. PMID:23413179

  16. First isolation of Leptospira interrogans from Lycalopex griseus (South American gray fox) in Argentina shows new MLVA genotype.

    PubMed

    Scialfa, Exequiel; Brihuega, Bibiana; Venzano, Agustín; Morris, Winston Eduardo; Bolpe, Jorge; Schettino, Mateo

    2013-01-01

    To identify carriers of Leptospira spp. in Argentina, wild animals were trapped in Buenos Aires Province during three nights, capturing 12 Didelphis albiventris (white-eared opossum), six Chaetophractus villosus (big hairy armadillo), five Lycalopex griseus (South American gray fox), and two Conepatus chinga (Molina's hog-nosed skunk). All were tested by microscopic agglutination test, and five (two gray foxes, two armadillos, and one skunk) were positive for Leptospira interrogans serovars Canicola and Icterohaemorrhagiae, L. borgpetersenii serovar Castellonis, and L. kirschneri serovar Grippotyphosa, at titers of 1:50 and 1:100. Kidney tissue from all animals was cultured, and one isolate of L. interrogans from a gray fox was obtained. Hamsters inoculated with the isolate died after 6 days with no macroscopic lesions at necropsy. However, histologic examination revealed glomerulonephritis, interstitial nephritis, and pneumonia. The Leptospira strain from the South American gray fox was analyzed serologically and its pathogenicity was established. Genotyping through multiple-locus variable-number tandem repeat analysis showed that the strain was a new genotype related to the L. interrogans serogroup Icterohaemorrhagiae. PMID:23307384

  17. Foraging behavior of lactating South American sea lions (Otaria flavescens) and spatial-temporal resource overlap with the Uruguayan fisheries

    NASA Astrophysics Data System (ADS)

    Riet-Sapriza, Federico G.; Costa, Daniel P.; Franco-Trecu, Valentina; Marín, Yamandú; Chocca, Julio; González, Bernardo; Beathyate, Gastón; Louise Chilvers, B.; Hückstadt, Luis A.

    2013-04-01

    Resource competition between fisheries and marine mammal continue to raise concern worldwide. Understanding this complex conflict requires data on spatial and dietary overlap of marine mammal and fisheries. In Uruguay the South American sea lions population has been dramatically declining over the past decade. The reasons for this population decline are unknown but may include the following: (1) direct harvesting; (2) reduced prey availability and distribution as a consequence of environmental change; or (3) biological interaction with fisheries. This study aims to determine resource overlap and competition between South American sea lions (SASL, Otaria flavescens, n=10) and the artisanal fisheries (AF), and the coastal bottom trawl fisheries (CBTF). We integrated data on sea lions diet (scat analysis), spatial and annual consumption estimates; and foraging behavior-satellite-tracking data from lactating SASL with data on fishing effort areas and fisheries landings. We found that lactating SASL are benthic divers and forage in shallow water within the continental shelf. SASL's foraging areas overlapped with CBTF and AF fisheries operational areas. Dietary analysis indicated a high degree of overlap between the diet of SASL and the AF and CBTF fisheries catch. The results of our work show differing degrees of spatial resource overlap with AF and CBTF, highlighting that there are differences in potential impact from each fishery; and that different management/conservation approaches may need to be taken to solve the fisheries-SASL conflict.

  18. Experimental transmission of Sarcocystis speeri Dubey and Lindsay, 1999 from the South American opossum (Didelphis albiventris) to the North American opossum (Didelphis virginiana).

    PubMed

    Dubey, J P; Speer, C A; Bowman, D D; Horton, K M; Venturini, C; Venturini, L

    2000-06-01

    Sarcocystis speeri Dubey and Lindsay, 1999 from the South American opossum Didelphis albiventris was successfully transmitted to the North American opossum Didelphis virginiana. Sporocysts from a naturally infected D. albiventris from Argentina were fed to 2 gamma-interferon knockout (KO) mice. The mice were killed 64 and 71 days after sporocyst feeding (DAF). Muscles containing sarcocysts from the KO mouse killed 71 DAF were fed to a captive D. virginiana; this opossum shed sporocysts 11 days after ingesting sarcocysts. Sporocysts from D. virginiana were fed to 9 KO mice and 4 budgerigars (Melopsittacus undulatus). Schizonts, sarcocysts, or both of S. speeri were found in tissues of all 7 KO mice killed 29-85 DAF; 2 mice died 39 and 48 DAF were not necropsied. Sarcocystis stages were not found in tissues of the 4 budgerigars fed S. speeri sporocysts and killed 35 DAE These results indicate that S. speeri is distinct from Sarcocystis falcatula and Sarcocystis neurona, and that S. speeri is present in both D. albiventris and D. virginiana. PMID:10864267

  19. South American Monsoon variability during the past 2,000 years from stable isotopic proxies and model simulations

    NASA Astrophysics Data System (ADS)

    Vuille, M.; Cruz, F. W.; Abbott, M.; Bird, B. W.; Burns, S. J.; Cheng, H.; Colose, C. M.; Kanner, L. C.; LeGrande, A. N.; Novello, V. F.; Taylor, B. L.

    2012-12-01

    The rapidly growing number of high-resolution stable isotopic proxies from speleothems, ice cores and lake sediments, located in the South American summer monsoon (SASM) belt, will soon allow for a comprehensive analysis of climate variability in the South American tropics and subtropics over the past ~ 2000 years. In combination with isotope-enabled General Circulation Models (GCMs) this offers new prospects for better understanding the spatiotemporal dynamics of the South American monsoon system and for diagnosing its sensitivities to external forcing mechanisms (solar, volcanic) and modes of ocean-atmosphere variability (e.g. ENSO and AMO). In this presentation we will discuss the rationale for interpreting isotopic excursions recorded in various proxies from the Andes, northeastern and southeastern Brazil as indicative of changes in monsoon intensity. We will focus on the past 2 millenia when isotopic proxies from the SASM region show a very coherent behavior regardless of the type of archive or their location. All proxies exhibit significant decadal to multidecadal variability, superimposed on large excursions during three key periods, the Medieval Climate Anomaly (MCA), the Little Ice Age (LIA) and the Current Warm Period (CWP). We interpret these three periods as times when the SASM mean state was significantly weakened (MCA and CWP) and strengthened (LIA), respectively. During the LIA each of the proxy archives considered contains the most negative delta-18O values recorded during the entire record length. On the other hand the monsoon strength is currently rather weak in a 2000- year historical perspective, rivaled only by the low intensity during the MCA. One interpretation of these centennial-scale climate anomalies suggests that they were at least partially driven by temperature changes in the northern hemisphere and in particular over the North Atlantic, leading to a latitudinal displacement of the ITCZ and a change in monsoon intensity and degree of

  20. Reconstructing the Mio-Pliocene South American Monsoon and Orographic Barrier Evolution (Angastaco Basin, NW Argentina)

    NASA Astrophysics Data System (ADS)

    Rohrmann, A.; Sachse, D.; Strecker, M. R.; Pingel, H.; Mulch, A.; Ponta, A.; Alonso, R. N.

    2013-12-01

    Intermontane basin deposits along the E Puna Plateau margin of the southern Andes, record the spatiotemporal evolution of tectonics and climate. In particular, the basin strata reflect the development of topographic barriers and associated paleo-hydrologic and ecological changes. Today, as a result of Andean orography, moisture penetrates into the arid interior and causes strong hydrological and surface-process gradients. It remains, however, unclear (1) as to when these conditions were established (i.e. initiation of the South American Monsoon, SAM); (2) how orographic barriers control hinterland aridification; and (3) how tectonically controlled rainfall distribution has impacted vegetation, erosion and deposition. By analogy with the present-day situation, stable isotopes of pedogenic carbonates or organic material from these basins may therefore reflect past hydrological changes due to range uplift. Here, we use a multi-proxy approach to reconstruct the Mio-Pliocene SAM and orographic barrier evolution including H-isotopes in hydrated volcanic glass, lipid biomarkers, as well as O and C isotopes of soil carbonates. The Angastaco Basin is located in the E Cordillera at ~25°45'S bordered by the eastern Puna margin and the Sierra de los Colorados (SC), to the west and east, respectively. Previous studies suggest humid conditions in this arid region by ~10.0 Ma, while initial uplift of the SC at ~5.0 Ma created an efficient orographic barrier and progressive aridification. We studied over 2 km of continuous basin strata, which contain numerous volcanic ashes, organic-rich paleosoils and lacustrine deposits. The sediments contain higher plant biomarkers suitable for compound-specific isotope analysis. We collected 68 samples for leaf-wax analysis, six volcanic ashes and 14 soil-carbonate horizons between 9-3 Ma. For all sediment samples we determined lipid biomarker distributions and concentrations and are in the process of analyzing their compound-specific H

  1. Assessment of fire emission inventories during the South American Biomass Burning Analysis (SAMBBA) experiment

    NASA Astrophysics Data System (ADS)

    Pereira, Gabriel; Siqueira, Ricardo; Rosário, Nilton E.; Longo, Karla L.; Freitas, Saulo R.; Cardozo, Francielle S.; Kaiser, Johannes W.; Wooster, Martin J.

    2016-06-01

    Fires associated with land use and land cover changes release large amounts of aerosols and trace gases into the atmosphere. Although several inventories of biomass burning emissions cover Brazil, there are still considerable uncertainties and differences among them. While most fire emission inventories utilize the parameters of burned area, vegetation fuel load, emission factors, and other parameters to estimate the biomass burned and its associated emissions, several more recent inventories apply an alternative method based on fire radiative power (FRP) observations to estimate the amount of biomass burned and the corresponding emissions of trace gases and aerosols. The Brazilian Biomass Burning Emission Model (3BEM) and the Fire Inventory from NCAR (FINN) are examples of the first, while the Brazilian Biomass Burning Emission Model with FRP assimilation (3BEM_FRP) and the Global Fire Assimilation System (GFAS) are examples of the latter. These four biomass burning emission inventories were used during the South American Biomass Burning Analysis (SAMBBA) field campaign. This paper analyzes and inter-compared them, focusing on eight regions in Brazil and the time period of 1 September-31 October 2012. Aerosol optical thickness (AOT550 nm) derived from measurements made by the Moderate Resolution Imaging Spectroradiometer (MODIS) operating on board the Terra and Aqua satellites is also applied to assess the inventories' consistency. The daily area-averaged pyrogenic carbon monoxide (CO) emission estimates exhibit significant linear correlations (r, p > 0.05 level, Student t test) between 3BEM and FINN and between 3BEM_ FRP and GFAS, with values of 0.86 and 0.85, respectively. These results indicate that emission estimates in this region derived via similar methods tend to agree with one other. However, they differ more from the estimates derived via the alternative approach. The evaluation of MODIS AOT550 nm indicates that model simulation driven by 3BEM and FINN

  2. Equatorial Ionospheric Irregularities Observed in the South American Sector During the December 2006 Geomagnetic Storm

    NASA Astrophysics Data System (ADS)

    Sahai, Y.; de Jesus, R.; Guarnieri, F. L.; Fagundes, P. R.; de Abreu, A. J.; Becker-Guedes, F.; Abalde, J. R.; Brunini, C.; Gende, M.; Cintra, T.; de Souza, V.; Pillat, V.; Lima, W.

    2009-05-01

    This investigation presents studies related to the observations of equatorial ionospheric irregularities in the ionospheric F-region in the South American sector during the intense geomagnetic storm in December 2006, during the period of low solar activity. The geomagnetic storm reached a minimum Dst of -147 nT at 0700 UT on 15 December. In this work ionospheric sounding data obtained between 13 and 16 December 2006 at Palmas (PAL; 10.2o S, 48.2o W; dip latitude 6.6o S) and São José dos Campos (SJC, 23.2o S, 45.9o W; dip latitude 17.6o S), Brazil, and Jicamarca (JIC, 12.0o S, 76.8o W; dip latitude 0.05o S), Peru, have been used. Also, vertical total electron content (VTEC) and phase fluctuations (TECU/min) from GPS observations obtained at Brasilia (BRAZ, 15.9o S, 47.9o W; dip latitude 11.7o S), Presidente Prudente (PPTE, 22.12° S, 51.4° W; dip latitude 14,9° S), Curitiba (PARA, 25.43o S, 49.21o W; dip latitude 18.4o S), Santa Maria (SMAR, 29.71o S, 53.07o W; dip latitude 19.6o S), Brazil, Bahia Blanca (VBCA, 38.7o S, 62.3o W; dip latitude 22.4o S) and Puerto Deseado (PDES, 47.7o S, 65.9o W, dip latitude 27.1o S), Argentina, during the period 13 to 16 December are presented. An unusual uplifting of the F-region during pre-reversal enhancement (PRE) on 14 December was possibly associated with a prompt penetration of electric field of magnetospheric origin after the storm sudden commencement (1414 UT on 14 December). On this geomagnetically disturbed night of 14-15 December, intense equatorial ionospheric irregularities were observed up to southern most GPS station PDES in Argentina. It should be mentioned that on the other nights viz., 12-13 and 13-14 December (both nights before the storm), and 15-16 December (recovery phase), the ionospheric irregularities are limited to only the Brazilian GPS stations. On the geomagnetically disturbed night of 14-15 December, strong oscillations were observed in the F-region base height possibly associated with Joule heating

  3. Pupil Rights in the "New" South Africa: Comparisons and Contrasts with American Constitutional Law.

    ERIC Educational Resources Information Center

    Delon, Floyd G.

    1996-01-01

    Examines provisions of the South African Constitution pertaining to pupil rights in conjunction with the construction the United States Supreme Court has placed on corresponding provisions of the U.S. Constitution. (46 footnotes) (MLF)

  4. Ancient DNA from the extinct South American giant glyptodont Doedicurus sp. (Xenarthra: Glyptodontidae) reveals that glyptodonts evolved from Eocene armadillos.

    PubMed

    Mitchell, Kieren J; Scanferla, Agustin; Soibelzon, Esteban; Bonini, Ricardo; Ochoa, Javier; Cooper, Alan

    2016-07-01

    Glyptodonts were giant (some of them up to ~2400 kg), heavily armoured relatives of living armadillos, which became extinct during the Late Pleistocene/early Holocene alongside much of the South American megafauna. Although glyptodonts were an important component of Cenozoic South American faunas, their early evolution and phylogenetic affinities within the order Cingulata (armoured New World placental mammals) remain controversial. In this study, we used hybridization enrichment and high-throughput sequencing to obtain a partial mitochondrial genome from Doedicurus sp., the largest (1.5 m tall, and 4 m long) and one of the last surviving glyptodonts. Our molecular phylogenetic analyses revealed that glyptodonts fall within the diversity of living armadillos. Reanalysis of morphological data using a molecular 'backbone constraint' revealed several morphological characters that supported a close relationship between glyptodonts and the tiny extant fairy armadillos (Chlamyphorinae). This is surprising as these taxa are among the most derived cingulates: glyptodonts were generally large-bodied and heavily armoured, while the fairy armadillos are tiny (~9-17 cm) and adapted for burrowing. Calibration of our phylogeny with the first appearance of glyptodonts in the Eocene resulted in a more precise timeline for xenarthran evolution. The osteological novelties of glyptodonts and their specialization for grazing appear to have evolved rapidly during the Late Eocene to Early Miocene, coincident with global temperature decreases and a shift from wet closed forest towards drier open woodland and grassland across much of South America. This environmental change may have driven the evolution of glyptodonts, culminating in the bizarre giant forms of the Pleistocene. PMID:27158910

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

    PubMed Central

    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

  6. Influence of Tertiary paleoenvironmental changes on the diversification of South American mammals: a relaxed molecular clock study within xenarthrans

    PubMed Central

    Delsuc, Frédéric; Vizcaíno, Sergio F; Douzery, Emmanuel JP

    2004-01-01

    Background Comparative genomic data among organisms allow the reconstruction of their phylogenies and evolutionary time scales. Molecular timings have been recently used to suggest that environmental global change have shaped the evolutionary history of diverse terrestrial organisms. Living xenarthrans (armadillos, anteaters and sloths) constitute an ideal model for studying the influence of past environmental changes on species diversification. Indeed, extant xenarthran species are relicts from an evolutionary radiation enhanced by their isolation in South America during the Tertiary era, a period for which major climate variations and tectonic events are relatively well documented. Results We applied a Bayesian approach to three nuclear genes in order to relax the molecular clock assumption while accounting for differences in evolutionary dynamics among genes and incorporating paleontological uncertainties. We obtained a molecular time scale for the evolution of extant xenarthrans and other placental mammals. Divergence time estimates provide substantial evidence for contemporaneous diversification events among independent xenarthran lineages. This correlated pattern of diversification might possibly relate to major environmental changes that occurred in South America during the Cenozoic. Conclusions The observed synchronicity between planetary and biological events suggests that global change played a crucial role in shaping the evolutionary history of extant xenarthrans. Our findings open ways to test this hypothesis further in other South American mammalian endemics like hystricognath rodents, platyrrhine primates, and didelphid marsupials. PMID:15115541

  7. Constraining the time of extinction of the South American fox Dusicyon avus (Carnivora, Canidae) during the late Holocene.

    NASA Astrophysics Data System (ADS)

    Prevosti, Francisco; Santiago, Fernando; Prates, Luciano; Salemme, Mónica; Martin, Fabiana

    2010-05-01

    The mass extinction at the end of the Pleistocene affected South America during the Late Pleistocene and the Early Holocene, when megamammals and large mammals disappeared. Several carnivores became extinct, like the sabretooth Smilodon, the short face bear (Arctotherium) and some large canids (i.e. Protocyon, Canis dirus). After this mass event virtually no carnivores became extinct in South America. The only exception is the fox Dusicyon avus, a middle sized canid (estimated body mass between 10-15 kg) with a more carnivore diet than the living South American foxes (i.e. Lycalopex culpaeus). The last record of the species comes from middle-late Holocene archaeological sites in the Pampean Region (Argentina) and Patagonia (Argentina and Chile). During the Late Pleistocene D. avus had a wide distribution, that covered part of Uruguay, Argentina (Buenos Aires province) and the southernmost Chile. Albeit some remains from late Holocene sites have been published, these remains lack of isotopic dates that could (allow?) constraint (to determine) the date of extinction of this fox. In this contribution we present several new records from the Pampean Region and Patagonia, and several taxon dates. The new records indicate that D. avus disappeared in the late Holocene at least ≈ 3000 years BP in the island of Tierra del Fuego (Patagonia) and ≈ 1600 BP in the continent. Since at this time humans were occupying most of the Pampas and Patagonia a revision of the causes behind the extinction of this fox is required.

  8. Asian American Interethnic Relations and Politics. Asians in America: The Peoples of East, Southeast, and South Asia in American Life and Culture Series, Volume 5.

    ERIC Educational Resources Information Center

    Ng, Franklin, Ed.

    The articles in this anthology address the complex subject of interethnic relations and Asian American politics, transcending ideas of Asian Americans as the model minority. The articles are: (1) "Opening the American Mind and Body: The Role of Asian American Studies" (Shirley Hume); (2) "Surviving Democracy's 'Mistake": Japanese Americans and the…

  9. The Relationship between Diet Quality and Acculturation of Immigrated South Asian American Adults and Their Association with Metabolic Syndrome

    PubMed Central

    Jackson, Robert T.; Momen, Bahram

    2016-01-01

    Even though the total SA American population is increasing rapidly, there is a paucity of information on the relationship between diet quality, acculturation and health outcomes such as Metabolic Syndrome (MetS) in the low-income South Asian (SA) sub-population. Our goal was to examine diet quality, degree of acculturation and their potential influence on MetS in a diverse sample of SA Americans. A convenience sample of 401 adult SA men and women were studied using a cross-sectional study design. Volunteers from two low-income community health clinics in Maryland were interviewed by questionnaires. MetS, defined by the consensus harmonized definition by the presence of ≥ 3 of the 5 abnormal indicators, was studied. An interviewer obtained an automated self-administered 24-hour Recall (ASA24) and an acculturation index (using a previously validated (SL-ASIA). SA had a composite HEI2010 score of 68 suggesting an overall need for diet improvements. Males had a higher diet quality (mean HEI2010 score) than females. Males with MetS had lower diet quality (68) than males without MetS (73). The converse was true for females (68 vs. 65). Americanized (more acculturated) subjects had a higher diet quality compared to less acculturated SA. Small differences were found in diet quality scores among SA adults from different countries. Less acculturated females, had a higher percentage of MetS and lower diet quality compared to males. These results suggest that interventions are needed in males and females who were less acculturated because they may have greater MetS and lower diet quality compared to more Americanized SA. PMID:27299862

  10. Identification of American shad spawning sites and habitat use in the Pee Dee River, North Carolina and South Carolina

    USGS Publications Warehouse

    Harris, Julianne E.; Hightower, Joseph E.

    2011-01-01

    We examined spawning site selection and habitat use by American shad Alosa sapidissima in the Pee Dee River, North Carolina and South Carolina, to inform future management in this flow-regulated river. American shad eggs were collected in plankton tows, and the origin (spawning site) of each egg was estimated; relocations of radio-tagged adults on spawning grounds illustrated habitat use and movement in relation to changes in water discharge rates. Most spawning was estimated to occur in the Piedmont physiographic region within a 25-river-kilometer (rkm) section just below the lowermost dam in the system; however, some spawning also occurred downstream in the Coastal Plain. The Piedmont region has a higher gradient and is predicted to have slightly higher current velocities and shallower depths, on average, than the Coastal Plain. The Piedmont region is dominated by large substrates (e.g., boulders and gravel), whereas the Coastal Plain is dominated by sand. Sampling at night (the primary spawning period) resulted in the collection of young eggs (≤1.5 h old) that more precisely identified the spawning sites. In the Piedmont region, most radio-tagged American shad remained in discrete areas (average linear range = 3.6 rkm) during the spawning season and generally occupied water velocities between 0.20 and 0.69 m/s, depths between 1.0 and 2.9 m, and substrates dominated by boulder or bedrock and gravel. Tagged adults made only small-scale movements with changes in water discharge rates. Our results demonstrate that the upstream extent of migration and an area of concentrated spawning occur just below the lowermost dam. If upstream areas have similar habitat, facilitating upstream access for American shad could increase the spawning habitat available and increase the population's size.

  11. Reproductive habitus, psychosocial health, and birth weight variation in Mexican immigrant and Mexican American women in south Texas.

    PubMed

    Fleuriet, K Jill; Sunil, T S

    2015-08-01

    The Latina Paradox, or persistent, unexplained variation in low birth weight rates in recently immigrated Mexican women and the trend toward higher rates in subsequent generations of Mexican American women, is most often attributed to unidentified sociocultural causes. We suggest herein that different disciplinary approaches can be synthesized under the constructs of reproductive habitus and subjective social status to identify influences of sociocultural processes on birth weight. Reproductive habitus are "modes of living the reproductive body, bodily practices, and the creation of new subjects through interactions between people and structures" (Smith-Oka, 2012: 2276). Subjective social status infers comparison of self to others based on community definitions of status or socioeconomic status (Adler 2007). We present results from a prospective study of low-income Mexican immigrant and Mexican American women from south Texas that tested the ability of reproductive habitus and subjective social status to elucidate the Latina Paradox. We hypothesized that reproductive habitus between Mexican immigrant women and Mexican American women inform different subjective social statuses during pregnancy, and different subjective social statuses mediate responses to psychosocial stressors known to correlate with low birth weight. Six hundred thirty-one women were surveyed for psychosocial health, subjective social status, and reproductive histories between 2011 and 2013. Eighty-three women were interviewed between 2012 and 2013 for status during pregnancy, prenatal care practices, and pregnancy narratives and associations. Birth weight was extracted from medical records. Results were mixed. Subjective social status and pregnancy-related anxiety predicted low birth weight in Mexican immigrant but not Mexican American women. Mexican immigrant women had significantly lower subjective social status scores but a distinct reproductive habitus that could explain improved psychosocial

  12. A Mid-South Perspective: African American Faith-based Organizations, HIV, and Stigma.

    PubMed

    Otey, Tamara D; Miller, Wendy Renee

    2016-01-01

    Shelby County, Tennessee has the fastest growing rate of HIV infection in the state, and the majority of new infections are in African Americans. In 2011, a Centers for Disease Control and Prevention report stated that Memphis (the largest city in Shelby County) ranked seventh highest in new HIV infections. Little research has addressed HIV-related themes in African American culture that could hinder HIV prevention measures. Our qualitative study engaged African American, faith-based leaders in areas with high rates of HIV in meaningful conversations regarding their attitudes toward HIV and those who are infected. Although faith-based leaders felt they had a role in HIV prevention, only 4% in our study had participated in HIV prevention activities, but they were open to HIV prevention programs. We found that faith-based leaders had limited knowledge of health disparities and ongoing stigma concerning HIV, which served as a major barrier to HIV prevention. PMID:27209431

  13. African-American Children and the Case for Community: Eleanora Tate's South Carolina Trilogy.

    ERIC Educational Resources Information Center

    Knuth, Carole Brown

    1998-01-01

    Three books by Eleanora Tate, "The Secret of Gumbo Grove" (1988), "Thank You, Dr. Martin Luther King, Jr.!" (1992), and "A Blessing in Disguise" (1995) are discussed with respect to their portrayal of African-American children and their responsibility to both themselves and their community. (MAK)

  14. South Texas Mexican American Use of Traditional Folk and Mainstream Alternative Therapies

    ERIC Educational Resources Information Center

    Martinez, Leslie N.

    2009-01-01

    A telephone survey was conducted with a large sample of Mexican Americans from border (n = 1,001) and nonborder (n = 1,030) regions in Texas. Patterns of traditional folk and mainstream complementary and alternative medicine (CAM) use were analyzed with two binary logistic regressions, using gender, self-rated health, confidence in medical…

  15. Engaging Secondary School and University Teachers in Modelling: Some Experiences in South American Countries

    ERIC Educational Resources Information Center

    Martinez-Luaces, Victor E.

    2005-01-01

    This article analyses mathematical modelling from several different perspectives and contrasts modelling with problem solving. Then it describes the ways in which modelling, applications, and problem solving are approached in several Latin American countries. It further describes workshops for secondary schools and for university teachers in which…

  16. Fulfilling the Promise: African American Educators Teach for Democracy in Jim Crow's South

    ERIC Educational Resources Information Center

    Preston-Grimes, Patrice

    2010-01-01

    America's civic community from the end of the Great Depression through the post World War II years was hardly rational or racially neutral in its uneven and unequal treatment of African Americans and other underrepresented groups. Conventional civic scholarship of the era has ignored the complexities of a racially segregated society that in theory…

  17. Community-based Music Education: Influences of Industrial Bands in the American South.

    ERIC Educational Resources Information Center

    LeCroy, Hoyt F.

    1998-01-01

    Presents a case study focusing on the mill-supported Lindale Band in Lindale, Georgia in order to examine the influences of industry on instrumental music education in the U.S. South. Investigates the history of U.S. industrial bands and the philosophical parallels between industry and progressive education. (CMK)

  18. Unlikely Crusader: John Eldred Swearingen and African-American Education in South Carolina

    ERIC Educational Resources Information Center

    Janak, Edward; Moran, Peter

    2010-01-01

    Although not a well-known figure either in educational or South Carolina history, John Eldred Swearingen had a profound impact on the schools of the Palmetto State. Guiding the schools to transition from 19th-century academies to 20th-century schools, Swearingen held office from 1907-1922. During these years, Swearingen oversaw unprecedented…

  19. New South American species of Cerambycinae, and notes on Corimbion balteum Martins (Coleoptera, Cerambycidae).

    PubMed

    Bezark, Larry G; Santos-Silva, Antonio; Galileo, Maria Helena M

    2016-01-01

    Three new species of Cerambycinae are described from South America: Mecometopus hauseri (Clytini), from Bolivia; Cycnoderus (Cycnoderus) metallicus (Rhopalophorini), from Venezuela; and Corimbion mutabile (Neoibidionini), from Ecuador. Mecometopus hauseri and Corimbion mutabile are included in previous keys. Corrections to the original description of Corimbion balteum Martins, 1970 are presented. PMID:27394841

  20. Elevated sexual risk behaviors among postincarcerated young African American males in the South.

    PubMed

    Ricks, JaNelle M; Crosby, Richard A; Terrell, Ivy

    2015-03-01

    The dramatic racial disparities in the rates of HIV/STIs(sexually transmitted infections) among African Americans make understanding broader structural factors that increase the risk for HIV/STIs crucial. The current study of young 564 African American men attending STI clinics investigated whether those who had ever been incarcerated reported recent sexual behaviors relatively more risky than their counterparts who had never been incarcerated. Participants were recruited from clinics treating STIs in three southern U.S. cities. Males 15 to 23 years of age who identified as Black/African American and reported recent (past 2 months) sexual activity were eligible. Linear mixed-effects models and generalized estimating equation models were used to assess associations between baseline incarceration history and sexual risk behavior over a 6-month follow-up period. Mean age was 19.6 years (SD = 1.87). At baseline, 240 (42.6%) men reported history of incarceration. Incarceration history predicted several risk behaviors over a 6-month follow-up period. Compared with those with no incarceration history, men previously incarcerated reported a desire to conceive a pregnancy (β = .40, p = .02), were less likely to have used a condom at last sex act (odds ratio = .91, p = .02) and were more likely to have used drugs and alcohol before sex in the past 2 months (β = .69, p < .001; β = .41, p < .001). A history of incarceration may influence the sexual risk behavior of young African American males. Prevention programs and interventions should intensify support for postincarceration African American males to help mitigate this behavior. PMID:24794821

  1. Food Safety by Using Machine Learning for Automatic Classification of Seeds of the South-American Incanut Plant

    NASA Astrophysics Data System (ADS)

    Lemanzyk, Thomas; Anding, Katharina; Linss, Gerhard; Rodriguez Hernández, Jorge; Theska, René

    2015-02-01

    The following paper deals with the classification of seeds and seed components of the South-American Incanut plant and the modification of a machine to handle this task. Initially the state of the art is being illustrated. The research was executed in Germany and with a relevant part in Peru and Ecuador. Theoretical considerations for the solution of an automatically analysis of the Incanut seeds were specified. The optimization of the analyzing software and the separation unit of the mechanical hardware are carried out with recognition results. In a final step the practical application of the analysis of the Incanut seeds is held on a trial basis and rated on the bases of statistic values.

  2. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (South Atlantic): American oyster. [Crassostrea virginica

    SciTech Connect

    Burrell, V.G. Jr.

    1986-07-01

    The American oyster, Crassostrea virginica, is an important commercial and recreational species. Spawning occurs continuously in warmer months. Larvae are planktonic and are distributed throughout estuaries by tidal currents. After a 2- to 3-week planktonic stage, larvae permanently attach to a solid substrate. In the South Atlantic region, this solid substrate is usually the shell of other oysters growing in the intertidal zone. This gregarious behaivor results in formation of massive intertidal reefs that are a prominent feature of high salinity bays, creeks and sounds in the region. These reefs serve as habitat and foraging grounds for other species. Oysters tolerate salinity from about 5 ppt to above 40 ppt and temperatures from below freezing to nearly 50/sup 0/C.

  3. Dr. Wouter Basson, Americans, and wild beasts: men's conspiracy theories of HIV/AIDS in the South African Lowveld.

    PubMed

    Niehaus, Isak; Jonsson, Gunvor

    2005-01-01

    This article investigates HIV/AIDS as a cosmological problem among Northern Sotho and Tsonga-speakers in the South African lowveld. Based on in-depth interviews with 70 informants (35 men and 35 women) I show how the attribution of blame for HIV/AIDS articulates gendered concerns. I suggest that women blamed men and envious nurses for spreading the virus and that these discourses expressed women's ideological association with the domestic domain. By contrast, men invoked conspiracy theories, blaming translocal agents--such as Dr. Wouter Basson, Americans, soldiers, and governments--for the pandemic. I suggest that these theories are informed by men's humiliating experiences of job losses and deindustrialization in the global labour market. My discussion highlights the need for HIV/AIDS interventions in order to address not only women's oppression but also men's gendered concerns. PMID:16019570

  4. “GETTING HIGH AND GETTING BY”: DIMENSIONS OF DRUG SELLING BEHAVIORS AMONG AMERICAN MEXICAN GANG MEMBERS IN SOUTH TEXAS

    PubMed Central

    Valdez, Avelardo; Sifaneck, Stephen J.

    2010-01-01

    This article discerns the role that Mexican American gang members play in drug markets, and the relationship between gang members’drug use and drug selling in South Texas. A four-part typology based on the two dimensions of gang type and gang member emerged from this qualitative analysis of 160 male gang members: Homeboys, Hustlers, Slangers, and Ballers. Major findings include the following: (1) many gang members are user/sellers and are not profit-oriented dealers, (2) gangs commonly do extend “protection” to drug-selling members, and (3) proximity to Mexican drug markets, adult prison gangs, and criminal family members may play important roles in whether these gang members have access and the profit potential to actually deal drugs. This research contributes to our complex intersections between gangs, drug using, and drug selling. PMID:21218191

  5. Traditional Healing, Biomedicine and the Treatment of HIV/AIDS: Contrasting South African and Native American Experiences

    PubMed Central

    Flint, Adrian

    2015-01-01

    Traditional healing remains an important aspect of many people’s engagement with healthcare and, in this, responses to the treatment of HIV/AIDS are no different. However, given the gravity of the global HIV/AIDS pandemic, there has been much debate as to the value of traditional healing in this respect. Accordingly, this paper explores the extent to which meaningful accommodation between the biomedical and traditional sectors is possible (and/or even desirable). It does this through a consideration of Native American and South African experiences, looking at how the respective groups, in which medical pluralism is common, have addressed the issue of HIV/AIDS. The paper points to the importance of developing “culturally appropriate” forms of treatment that emphasise complementary rather than adversarial engagement between the traditional and biomedical systems and how policymakers can best facilitate this. PMID:25903057

  6. Hematozoa of forest birds in American Samoa - Evidence for a diverse, indigenous parasite fauna from the South Pacific

    USGS Publications Warehouse

    Atkinson, C.T.; Utzurrum, R.C.; Seamon, J.O.; Savage, Amy F.; Lapointe, D.A.

    2006-01-01

    Introduced avian diseases pose a significant threat to forest birds on isolated island archipelagos, especially where most passerines are endemic and many groups of blood-sucking arthropods are either absent or only recently introduced. We conducted a blood parasite survey of forest birds from the main islands of American Samoa to obtain baseline information about the identity, distribution and prevalence of hematozoan parasites in this island group. We examined Giemsa-stained blood smears from 857 individual birds representing 20 species on Tutuila, Ofu, Olosega, and Ta'u islands. Four hematozoan parasites were identified - Plasmodium circumflexum (1%, 12/857), Trypanosoma avium (4%, 32/857), microfilaria (9%, 76/857), and an Atoxoplasma sp. (<1%, 2/857). Infections were found in seven indigenous bird species from the archipelago. Overall prevalence of infection varied significantly among bird species, individual islands, and between Tutuila and the more isolated Manu'a group of islands. Infections with Plasmodium, Trypanosoma, and filarial worms occurred throughout the archipelago, including islands without introduced birds. There was a statistically significant difference in the overall prevalence of infection before and after Hurricane Olaf in February 2005, suggesting that catastrophic hurricanes may influence the dynamics of parasite infections. Given the central location of American Samoa in the South Pacific, it is likely that avian malaria and other hematozoan parasites are indigenous and widespread at least as far as the central South Pacific. Their natural occurrence may provide some immunological protection to indigenous birds in the event that other closely related parasites are accidentally introduced to the region.

  7. SURVEY FOR INFECTIOUS DISEASE IN THE SOUTH AMERICAN FUR SEAL (ARCTOCEPHALUS AUSTRALIS) POPULATION AT PUNTA SAN JUAN, PERU.

    PubMed

    Jankowski, Gwen; Adkesson, Michael J; Saliki, Jeremiah T; Cárdenas-Alayza, Susana; Majluf, Patricia

    2015-06-01

    The Peruvian population of the South American fur seal ( Arctocephalus australis ) is a distinct evolutionarily significant unit that is endangered. One of the largest rookeries for this species in Peru is located within the Punta San Juan marine protected area (15°22'S, 75°12'W). To better understand the current health status of this population, exposure to 10 pinniped pathogens was evaluated in adult female fur seals (n=29) via serology and polymerase chain reaction (PCR) techniques in November 2010. The results suggest this population is naïve to canine and phocine distemper viruses (serum neutralization test), five Leptospira interrogans serovars (microscopic agglutination test), and Brucella canis (card test). Indirect fluorescent antibody testing for Toxoplasma gondii , Neospora caninum , and Sarcocystis neurona was also uniformly negative. PCR testing of nasal swabs using previously described Mycoplasma spp. primers was positive in 37.9% (11/29) of samples. One animal was positive via card test for Brucella abortus , whereas 53.7% (15/28) were positive or suspect using a marine Brucella competitive enzyme-linked immunosorbent assay. Antibody to phocine herpesvirus-1 (PHV-1) was identified in 85.7% (24/28) of the sampled population by serum neutralization testing. Overall, exposure to Mycoplasma spp., Brucella spp., and PHV-1 was observed, but results demonstrated low to no exposure to many key pinniped pathogens. The expansion of human populations, agriculture, and industry along the Peruvian coast may lead to increased pathogen exposure from human, domestic, and wild animal sources. The naïve nature of this key population of South American fur seals raises concerns about potential risk for disease outbreaks. PMID:26056875

  8. A review of South American monsoon variability over the past 2 millennia based on stable isotopic proxies and model simulations

    NASA Astrophysics Data System (ADS)

    Vuille, M.; Cruz, F. W.; Abbott, M.; Bird, B. W.; Burns, S. J.; Cheng, H.; Colose, C. M.; Kanner, L. C.; LeGrande, A. N.; Novello, V.

    2013-05-01

    The growing number of high-resolution stable isotopic proxies (speleothems, ice cores, lake sediments) from the South American summer monsoon (SASM) belt, when combined with isotope-enabled General Circulation Models (GCMs), offers new prospects for better understanding the spatiotemporal dynamics of the South American monsoon system and for diagnosing its sensitivities to external forcings and internal modes of ocean-atmosphere variability over the past 2 millennia. In this presentation we will discuss the rationale for interpreting isotopic excursions recorded in various proxies from the SASM region as indicative of changes in monsoon intensity. Over the past 2 millennia isotopic proxies from the SASM belt display a fairly coherent behavior, regardless of the type of archive considered. All proxies exhibit significant decadal to multidecadal variability, superimposed on large excursions during three key periods, the Medieval Climate Anomaly (MCA), the Little Ice Age (LIA) and the Current Warm Period (CWP). We interpret these three periods as times when the SASM mean state was significantly weakened (MCA and CWP) and strengthened (LIA), respectively. During the LIA each of the proxy archives considered contains the most negative δ18O values recorded during the entire record length. On the other hand the monsoon strength is currently rather weak in a 2000- year historical perspective, rivaled only by the low intensity during the MCA. One interpretation of these centennial-scale climate anomalies suggests that they were at least partially driven by temperature changes in the northern hemisphere and in particular over the North Atlantic, leading to a latitudinal displacement of the ITCZ and a change in monsoon intensity and degree of rainout upstream of the proxy locations, over the tropical continent. This interpretation is supported by several independent proxy archives and modeling studies.

  9. Southern Education and the American Recovery and Reinvestment Act: An Analysis of Historic Federal Funding to Improve the South's Low-Achieving Schools. Issue Brief

    ERIC Educational Resources Information Center

    Southern Education Foundation, 2009

    2009-01-01

    The new federal stimulus law, the American Recovery and Reinvestment Act of 2009 (ARRA), offers Southern states a historic opportunity to improve public education from pre-school through college especially for low income students. ARRA allocates over $100 billion directly to the 15 states of the South for creating jobs and spurring economic…

  10. Student Perceptions of Science Teacher Actions in Two Culturally Diverse Middle-Level Science Classrooms: A Case Study in the American Deep South.

    ERIC Educational Resources Information Center

    McGinnis, J. Randy

    The purpose of this study was to give voice to students' perceptions in two science classrooms taught by two white teachers in an urban multicultural middle-level school situated in the American Deep South. Student participants were 35 students of different ethnicities in grades 7 and 8. The theoretical reference used is social contextual, a…

  11. Community Background Reports: The Cheyenne River Sioux Reservation, South Dakota. National Study of American Indian Education, Series I, No. 6, Final Report.

    ERIC Educational Resources Information Center

    Mueller, Wolfgang

    As a part of the Final Report of the National Study of American Indian Education, this document describes the town of Eagle Butte, South Dakota, on the Cheyenne River Sioux Reservation approximately 100 years after the signing of the 1868 Treaty with the Sioux. A 3-member research team collected data via interviews with students, parents,…

  12. South American perspective of the International Charter "Space and Major Disasters"

    NASA Astrophysics Data System (ADS)

    Mahmood, A.; Cubero-Castan, E.; Platzeck, G.; Bequignon, J.

    2008-01-01

    The International Charter "Space and Major Disasters" is about joint operations and tasking of imaging satellites and other space resources of the member space agencies and operators in the delivery of information products to assist in responding to disasters of natural and technological causes. Authorized Users, who are the civil protection, emergency response or similar organizations of a state that is member of the Charter, can request the data and products. A specialist, called the Project Manager (PM), manages the overall data acquisition and delivery process. Regional initiatives, as for the Latin American countries, are under way to involve PMs from non-member states to have access to satellite data and apply these to disaster coverage in their respective regions. Volcanic eruptions are typical examples of disasters that affect the Latin American countries. A few Charter activations on this disaster type are described to highlight the information products provided under the Charter.

  13. Type I interferon induction is correlated with attenuation of a South American eastern equine encephalitis virus strain in mice

    PubMed Central

    Gardner, Christina L.; Yin, Jun; Burke, Crystal W.; Klimstra, William B.; Ryman, Kate D.

    2009-01-01

    North American eastern equine encephalitis virus (NA-EEEV) strains cause high mortality in humans, whereas South American strains (SA-EEEV) are typically avirulent. To clarify mechanisms of SA-EEEV attenuation, we compared mouse-attenuated BeAr436087 SA-EEEV, considered an EEEV vaccine candidate, with mouse-virulent NA-EEEV strain, FL93-939. Although attenuated, BeAr436087 initially replicated more efficiently than FL93-939 in lymphoid and other tissues, inducing systemic IFN-α/β release, whereas FL93-939 induced little. BeAr436087 was more virulent than FL93-939 in IFN-α/β-deficient mice, confirming that type I IFN responses determined attenuation, but the viruses were similarly sensitive to IFN-α/β priming in vitro. Infection with BeAr436087 protected against FL93-939 disease/death, even when given 8 h afterward, suggesting that the environment produced by BeAr436087 infection attenuated FL93-939. We conclude that avoidance of IFN-α/β induction is factor for FL93-939. Furthermore, BeAr436087 could be used for vaccination and therapeutic treatment in the event of exposure to NA-EEEV during a bioterrorism attack. PMID:19539968

  14. Use of South American Land Data Assimilation System (SALDAS) to Assess Impacts of Biofuel Expansion on Water Resources in Brazil

    NASA Astrophysics Data System (ADS)

    Goncalves, L.; De Mattos, J. Z.; Scarpare, F.; Galdos, M. V.; Scanlon, B.; Long, D.

    2013-12-01

    Large scale expansion of sugarcane production in Brazil is very positive in terms of biofuels and greenhouse gases; however, potential impacts on water resources are uncertain. The objective of this analysis is to assess potential impacts of biofuel expansion in Central South Brazil on water resources using the South American Land Data Assimilation System (SALDAS). SALDAS is driven by 3 hourly atmospheric forcing. Limited surface observations have resulted in use of remotely sensed data merged with surface observations to calculate precipitation and shortwave radiation fields. SALDAS simulates partitioning of water and energy in response to spatiotemporal variability in climate forcing and land use change related to biofuel expansion. The impacts of land use changes related to biofuel expansion will be examined by evaluating water and energy fluxes in areas of different land use and substituting space for time. Output from SALDAS will be compared with coarser resolution Global Land Data Assimilation System (GLDAS) and other more traditional modeling approaches, such as CROPWAT, to estimate changes in water use from biofuel expansion. Land surface models provide an excellent reconnaissance tool to better understand the hydrology of regional systems in response to climate and land use in data constrained regions.

  15. Solitary foraging in the ancestral South American ant, Pogonomyrmex vermiculatus. Is it due to constraints in the production or perception of trail pheromones?

    PubMed

    Torres-Contreras, Hugo; Olivares-Donoso, Ruby; Niemeyer, Hermann M

    2007-02-01

    Several North American species of Pogonomyrmex harvester ants exhibit group foraging, whereas South American species are exclusively solitary foragers. The composition of the secretions of the poison and Dufour glands in the South American species, Pogonomyrmex vermiculatus, were analyzed, and the secretions and their components were tested as trail pheromones in laboratory bioassays. The major compounds in the poison gland were the alkylpyrazines, 2,5-dimethylpyrazine, 2,3,5-trimethylpyrazine, and 3-ethyl-2,5-dimethylpyrazine. The Dufour gland contained five alkanes, from tridecane to heptadecane, with pentadecane being most abundant. In behavioral bioassays, poison gland extracts and the mixture of pyrazines produced a trail pheromone effect, whereas the Dufour gland extracts and the alkanes had no effect on ant locomotion. We conclude that group foraging in P. vermiculatus does not arise from the inability to produce or detect possible pheromones, but rather, from physiological and/or ecological factors. PMID:17187299

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

    PubMed Central

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

    2014-01-01

    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. PMID:25143041

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

    PubMed

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

    2014-10-01

    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. PMID:25143041

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

    PubMed

    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. PMID:25353346

  19. Emissions from Pre-Hispanic Metallurgy in the South American Atmosphere

    PubMed Central

    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. PMID:25353346

  20. Intercomparison of Model Simulations of the Impact of 1997/98 El Nino on South American Summer Monsoon

    NASA Technical Reports Server (NTRS)

    Zhou, Jiayu; Lau, K.-M.; Lau, William K. M. (Technical Monitor)

    2002-01-01

    The simulations of climatology and response of the South American summer monsoon (SASM) to the 1997/98 El Nino are investigated using six atmospheric general circulation models. Results show all models simulate the large-scale features of the SASM reasonably well. However, both stationary and seasonal components of the surface pressure are overestimated, resulting in an excessively strong SASM in the model climatology. The low-level northwesterly jet over eastern foothills of the Andes is not well resolved because of the coarse resolution of the models. Large rainfall simulation biases are found in association with the Andes and the Atlantic ITCZ, indicating model problems in handling steep mountains and parameterization of convective processes. The simulation of the 1997/98 El Nino impact on SASM is examined based on an ensemble of ten two-year (September 1996 - August 1998) integration. Results show that most models can simulate the large-scale tropospheric warming response over the tropical central Pacific, including the dynamic response of Rossby wave propagation of the Pacific-South America (PSA) pattern that influences remote areas. Deficiencies are found in simulating the regional impacts over South America. Model simulation fails to capture the southeastward expansion of anomalously warm tropospheric air. As a result, the upper tropospheric anomalous high over the subtropical Andes is less pronounced, and the enhancement of subtropical westerly jet is displaced 5deg-10deg equatorward compared to the observed. Over the Amazon basin, the shift of Walker cell induced by El Nino is not well represented, showing anomalous easterlies in both upper and lower troposphere.

  1. O the Interannual Variability of South American Climate and the Southern Oscillation.

    NASA Astrophysics Data System (ADS)

    Aceituno, Patricio

    The functioning of the Southern Oscillation (SO) over South America and the surrounding tropical Atlantic and Eastern Pacific Oceans is studied through analyses of SO-related anomalies in various surface and upper-air fields which reveal the three-dimensional characteristics of the SO in this region. Correlation analyses are complemented by case studies of extreme episodes during the negative and positive SO phases (defined as positive by anomalously high/low pressure at Tahiti/Darwin). Most pronounced is the anomalously low pressure and high SST over the Eastern Pacific during the negative SO phase. The perennially positive SO-pressure correlations over the tropical Eastern Pacific extend eastward into the North Atlantic and Southern South America during the respective winter semester. The anomalously warm waters in the tropical Eastern Pacific during the negative SO phase are consistent with positive 500 and 200 mb departures over the tropics indicating a relatively warm troposphere. During austral winter anomalously abundant rainfall in Central Chile during the negative SO phase appears related to a weak and northward displaced South Pacific subtropical high and enhanced upper-air westerlies. By contrast, relatively dry conditions prevail in the northwestern portion of the continent. These seem related to a southward displaced near-equatorial trough, concomitant with enhanced pressure over the Caribbean. During the austral summer, SO-related climate anomalies grow most pronounced, particularly conspicuous being the following three anomaly regimes of the negative SO phase. (i) The excessive rainfall along the Ecuador -Peru littoral and the adjacent open equatorial Pacific is consistent with an intensified and southward displaced near-equatorial trough. (ii) In the tropical North Atlantic during the latter part of the austral summer, the near -equatorial trough is displaced northward, the meridional pressure gradient is reduced, the Northeast trades are weak, the

  2. Late Quaternary environmental change in the interior South American tropics: new insight from leaf wax stable isotopes

    NASA Astrophysics Data System (ADS)

    Fornace, Kyrstin L.; Whitney, Bronwen S.; Galy, Valier; Hughen, Konrad A.; Mayle, Francis E.

    2016-03-01

    Stable isotope analysis of leaf waxes in a sediment core from Laguna La Gaiba, a shallow lake located at the Bolivian margin of the Pantanal wetlands, provides new perspective on vegetation and climate change in the lowland interior tropics of South America over the past 40,000 years. The carbon isotopic compositions (δ13C) of long-chain n-alkanes reveal large shifts between C3- and C4-dominated vegetation communities since the last glacial period, consistent with landscape reconstructions generated with pollen data from the same sediment core. Leaf wax δ13C values during the last glacial period reflect an open landscape composed of C4 grasses and C3 herbs from 41-20 ka. A peak in C4 abundance during the Last Glacial Maximum (LGM, ∼21 ka) suggests drier or more seasonal conditions relative to the earlier glacial period, while the development of a C3-dominated forest community after 20 ka points to increased humidity during the last deglaciation. Within the Holocene, large changes in the abundance of C4 vegetation indicate a transition from drier or more seasonal conditions during the early/mid-Holocene to wetter conditions in the late Holocene coincident with increasing austral summer insolation. Strong negative correlations between leaf wax δ13C and δD values over the entire record indicate that the majority of variability in leaf wax δD at this site can be explained by variability in the magnitude of biosynthetic fractionation by different vegetation types rather than changes in meteoric water δD signatures. However, positive δD deviations from the observed δ13C- δD trends are consistent with more enriched source water and drier or more seasonal conditions during the early/mid-Holocene and LGM. Overall, our record adds to evidence of varying influence of glacial boundary conditions and orbital forcing on South American Summer Monsoon precipitation in different regions of the South American tropics. Moreover, the relationships between leaf wax stable

  3. 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).

    PubMed

    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. PMID:25056712

  4. 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)

    USGS Publications Warehouse

    Ramey, Andy M.; Walther, Patrick; Link, Paul Karl; Poulson, Rebecca L.; Wilcox, Benjamin R.; Newsome, George M.; Spackman, Erica; Brown, J.; Stallknecht, David E.

    2016-01-01

    Relative to research focused on intercontinental 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 were 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.

  5. Phylogenetic analysis provides evidence of interactions between Italian heterosexual and South American homosexual males as the main source of national HIV-1 subtype C epidemics.

    PubMed

    Lai, Alessia; Bozzi, Giorgio; Franzetti, Marco; Binda, Francesca; Simonetti, Francesco R; Micheli, Valeria; Meraviglia, Paola; Corsi, Paola; Bagnarelli, Patrizia; De Luca, Andrea; Ciccozzi, Massimo; Zehender, Gianguglielmo; Zazzi, Maurizio; Balotta, Claudia

    2014-05-01

    The HIV-1 clade C is prevalent worldwide and spread from Africa to South East Asia and South America early in the course of the epidemic. As a consequence of migration waves about 13% of the Italian HIV-1 epidemic is sustained by this clade. Two hundred fifty-four C pol sequences from the Italian ARCA database collected during 1997-2011 were analyzed. Epidemiological networks and geographical fluxes were identified through phylogeny using Bayesian approaches. Patients' country of origin was Italy, Africa, South America, and South East Asia for 44.9%, 23.6%, 4.7%, and 1.6%, respectively. Heterosexuals and men having sex with men accounted for 83.2% and 16.8%, respectively. Modality of infection was distributed differently: heterosexuals were largely prevalent among Italians (84.1%) and Africans (95.3%), while men having sex with men predominated among South Americans (66.7%). Eight significant clusters encompassing 111 patients (43.7%) were identified. Comparison between clustering and non-clustering patients indicated significant differences in country of origin, modality of infection and gender. Men having sex with men were associated to a higher probability to be included in networks (70% for men having sex with men vs. 30.3% for heterosexuals). Phylogeography highlighted two significant groups. One contained Indian strains and the second encompassed South Americans and almost all Italian strains. Phylogeography indicated that the spread of C subtype among Italians is related to South American variant. Although Italian patients mainly reported themselves as heterosexuals, homo-bisexual contacts were likely their source of infection. Phylogenetic monitoring is warranted to guide public health interventions aimed at controlling HIV infection. PMID:24482324

  6. Characteristics of problem drinking in an urban South American indigenous population.

    PubMed

    Seale, J Paul; Shellenberger, Sylvia; Sanchez, Nelia; Vogel, Robert L; Villalobos, Elibeth; Girton, Fred S; Seale, Dana M; Okosun, Ike S

    2010-11-01

    This 2002 Medcen Foundation-funded study explored characteristics of problem drinking among 211 urban Venezuelan Native Americans of Arawak origin. Prevalence of problem drinking using Alcohol Use Disorders Identification Tests was 88.5% among men and 17.3% among women. Periodic binge drinking was marked by loss of control, failure to meet obligations, and alcohol-related trauma. Focus group participants noted that previous occasional binge drinking by men has been replaced by frequent male and female heavy weekend drinking, violence, and death. Limitations and implications are discussed. Awareness of high levels of problem drinking and desire for assistance present compelling mandates for community intervention efforts. PMID:20388009

  7. Solar forcing of the stream flow of a continental scale South American river.

    PubMed

    Mauas, Pablo J D; Flamenco, Eduardo; Buccino, Andrea P

    2008-10-17

    Solar forcing on climate has been reported in several studies although the evidence so far remains inconclusive. Here, we analyze the stream flow of one of the largest rivers in the world, the Paraná in southeastern South America. For the last century, we find a strong correlation with the sunspot number, in multidecadal time scales, and with larger solar activity corresponding to larger stream flow. The correlation coefficient is r=0.78, significant to a 99% level. In shorter time scales we find a strong correlation with El Niño. These results are a step toward flood prediction, which might have great social and economic impacts. PMID:18999720

  8. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (South Atlantic). American eel

    SciTech Connect

    Van Den Avyle, M.J.

    1984-07-01

    The American eel, Anguilla rostrata, is an ecologically and economically important catadromous species that occupies freshwater streams, rivers, brackish estuaries, and the open ocean during various phases of its life cycle. Adult eels apparently spawn in the Sargasso Sea, and ocean currents transport the developing larvae northward until the young metamorphose into juveniles capable of swimming shoreward and moving upstream into coastal areas, estuaries, and rivers. Developing eels commonly remain in freshwater or brackish area for 10 to 12 years before migrating to spawn. American eels tend to be bottom-dwellers and feed on a variety of fauna that occupy the same habitats. Eels occupy areas having wide ranges of temperature, salinity, and other environmental factors, suggesting broad tolerance limits, but few studies of requirements have been reported. Salinity patterns and water currents created by river discharges into coastal areas apparently provide the gradient that cues shoreward migration of juvenile eels. Alteration of patterns of freshwater inflows to estuaries and bays could affect upstream migrations. 73 references, 3 figures, 1 table.

  9. Zoogeography of South American Forest-Dwelling Bats: Disjunct Distributions or Sampling Deficiencies?

    PubMed

    da Rocha, Patrício Adriano; Ferrari, Stephen Francis; Feijó, Anderson; Gouveia, Sidney Feitosa

    2015-01-01

    Many forest-dwelling bats are purported to be widespread in South America, although records are scant from the vast diagonal belt of dry ecosystems that straddles the continent, implying possible sampling deficiencies. Here, we investigate this possibility in the case of four species of bat (Centronycteris maximiliani, Lampronycteris brachyotis, Peropteryx kappleri and Trinycteris nicefori), evaluating whether their disjunct present-day distributions reflect their true zoogeographic characteristics or the subsampling of intermediate zones. We use environmental niche modelling (ENM) in an ensemble approach, combining four different modeling techniques, and using niche descriptors based on climatic and remote sensing data, to estimate the potential distribution of the four species. The models indicate that all four species have disjunct distributions in the Amazon and Atlantic forest biomes. The one possible exception is P. kappleri, which the models indicated might potentially occur in humid forest enclaves in western Brazil and eastern Bolivia. The present-day distribution of the species may date back to the Plio-Pleistocene, when the forested biomes of South America were more extensive and connected. Further studies of different chiropteran lineages may provide additional insights into the historic processes of faunal interchange between the Amazon and Atlantic forest biomes. PMID:26186587

  10. The South American Land Data Assimilation System (SALDAS) 5-Year Retrospective Atmospheric Forcing Datasets

    NASA Technical Reports Server (NTRS)

    deGoncalves, Luis Gustavo G.; Shuttleworth, William J.; Vila, Daniel; Larroza, Elaine; Bottino, Marcus J.; Herdies, Dirceu L.; Aravequia, Jose A.; De Mattos, Joao G. Z.; Toll, David L.; Rodell, Matthew; Houser, Paul

    2008-01-01

    The definition and derivation of a 5-year, 0.125deg, 3-hourly atmospheric forcing dataset for the South America continent is described which is appropriate for use in a Land Data Assimilation System and which, because of the limited surface observational networks available in this region, uses remotely sensed data merged with surface observations as the basis for the precipitation and downward shortwave radiation fields. The quality of this data set is evaluated against available surface observations. There are regional difference in the biases for all variables in the dataset, with biases in precipitation of the order 0-1 mm/day and RMSE of 5-15 mm/day, biases in surface solar radiation of the order 10 W/sq m and RMSE of 20 W/sq m, positive biases in temperature typically between 0 and 4 K, depending on region, and positive biases in specific humidity around 2-3 g/Kg in tropical regions and negative biases around 1-2 g/Kg further south.

  11. A giant frog with South American affinities from the Late Cretaceous of Madagascar

    PubMed Central

    Evans, Susan E.; Jones, Marc E. H.; Krause, David W.

    2008-01-01

    Madagascar has a diverse but mainly endemic frog fauna, the biogeographic history of which has generated intense debate, fueled by recent molecular phylogenetic analyses and the near absence of a fossil record. Here, we describe a recently discovered Late Cretaceous anuran that differs strikingly in size and morphology from extant Malagasy taxa and is unrelated either to them or to the predicted occupants of the Madagascar–Seychelles–India landmass when it separated from Africa 160 million years ago (Mya). Instead, the previously undescribed anuran is attributed to the Ceratophryinae, a clade previously considered endemic to South America. The discovery offers a rare glimpse of the anuran assemblage that occupied Madagascar before the Tertiary radiation of mantellids and microhylids that now dominate the anuran fauna. In addition, the presence of a ceratophryine provides support for a controversial paleobiogeographical model that posits physical and biotic links among Madagascar, the Indian subcontinent, and South America that persisted well into the Late Cretaceous. It also suggests that the initial radiation of hyloid anurans began earlier than proposed by some recent estimates. PMID:18287076

  12. Identification of new SNPs in native South American populations by resequencing the Y chromosome.

    PubMed

    Geppert, M; Ayub, Q; Xue, Y; Santos, S; Ribeiro-dos-Santos, Â; Baeta, M; Núñez, C; Martínez-Jarreta, B; Tyler-Smith, C; Roewer, L

    2015-03-01

    The Y-chromosomal genetic landscape of South America is relatively homogenous. The majority of native Amerindian people are assigned to haplogroup Q and only a small percentage belongs to haplogroup C. With the aim of further differentiating the major Q lineages and thus obtaining new insights into the population history of South America, two individuals, both belonging to the sub-haplogroup Q-M3, were analyzed with next-generation sequencing. Several new candidate SNPs were evaluated and four were confirmed to be new, haplogroup Q-specific, and variable. One of the new SNPs, named MG2, identifies a new sub-haplogroup downstream of Q-M3; the other three (MG11, MG13, MG15) are upstream of Q-M3 but downstream of M242, and describe branches at the same phylogenetic positions as previously known SNPs in the samples tested. These four SNPs were typed in 100 individuals belonging to haplogroup Q. PMID:25303787

  13. The genetic legacy of polyploid Bolivian Daphnia: the tropical Andes as a source for the North and South American D. pulicaria complex.

    PubMed

    Mergeay, Joachim; Aguilera, Ximena; Declerck, Steven; Petrusek, Adam; Huyse, Tine; De Meester, Luc

    2008-04-01

    We investigated genetic variation in asexual polyploid members of the water flea Daphnia pulex complex from a set of 12 Bolivian high-altitude lakes. We used nuclear microsatellite markers to study genetic relationships among all encountered multilocus genotypes, and combined this with a phylogenetic approach using DNA sequence data of three mitochondrial genes. Analyses of mitochondrial gene sequence divergence showed the presence of three very distinct clades that likely represent cryptic undescribed species. Our phylogenetic results suggest that the Daphnia pulicaria group, a complex of predominantly North American species that has diversified rapidly since the Pleistocene, has its origin in South America, as specific tests of topology indicated that all three South American lineages are ancestral to the North American members of this species group. A comparison between variation of nuclear and mitochondrial markers revealed that closely related polyploid nuclear genotypes sometimes belonged to very divergent mitochondrial lineages, while distantly related nuclear genotypes often belonged to the same mitochondrial lineage. This discrepancy suggests that these South American water fleas originated through reciprocal hybridization between different endemic, sexually reproducing parental lineages. It is also likely that polyploidy of the investigated lineages resulted from this hybridization. Nevertheless, no putative diploid parental lineages were found in the studied region. PMID:18284570

  14. Tropical forest changes during the late quaternary in African and South American lowlands

    NASA Astrophysics Data System (ADS)

    Servant, Michel; Maley, Jean; Turcq, Bruno; Absy, Maria-Lucia; Brenac, Patrice; Fournier, Marc; Ledru, Marie-Pierre

    1993-05-01

    Arboreal pollen and montane elements of Late Quaternary pollen assemblages from three lacustrine cores (West Cameroon, southeastern Amazonia and central Brazil) are correlated, by the radiocarbon chronology, with other palaeoenvironmental records in Africa and South America. We observe in both continents a well-developed dense forest at 30,000 and 9000 yr B.P. The succession of vegetation types during the Late Quaternary appeared strongly related to the regional conditions: (1) the dense forest was more or less degraded depending on the regions during the last full glacial period (20,000-15,000 yr B.P.); (2) a slow increase of tree elements is evidenced in some areas during the Late Glacial (15,000-10,000 yr B.P.), whereas short-term fluctuations occurred in central Brazil during the same time; (3) a strong regression of the forest during the middle Holocene (6000-5000 yr B.P.), in the southern tropical zone of South America, was in opposition to a full forest development in Africa. In both continents two main features characterize the tropical forest evolution: (1) Montane elements developed in the lowlands during the last glacial period and in some southern or northern regions during the early Holocene; and (2) the climate seasonality was enhanced in several regions since 8500-7500 yr B.P. For a tentative explanation, we relate the cold or cool climate, inferred by palaeoecological evidences in the glacial period and glacial-interglacial transition, to polar air-masses reaching more frequently the tropical zone. This interpretation explains the apparent contradiction between the markedly low temperature of the continental lowlands opposed: (1) at 18,000 yr B.P., to the 1-2°C lower Sea Surface Temperature of tropical oceans and (2) to the global warming during the late glacial. During the middle and Late Holocene, climate evolution was mainly influenced by the latitudinal shift of the ITCZ positions in July and January and, in South America, by short-term changes

  15. Two new species of freshwater flatworms (Platyhelminthes: Tricladida: Continenticola) from South American caves.

    PubMed

    Souza, Stella; Morais, Ana Laura; Bichuette, Maria Elina; Leal-Zanchet, Ana

    2016-01-01

    The diversity of freshwater triclads in the Neotropical region is considered to be low, but extensive areas of South America remain almost unexplored. Herein we describe two cave-dwelling, new species of Girardia, one from a transition zone of the Cerrado and Caatinga phytophysiognomies and the other from the Cerrado phytophysiognomy. The species from the Cerrado-Caatinga transition is a troglobite, eyeless and whitish; the species from the Cerrado area is possibly a troglophile, since it shows heavily pigmented body and eyes. Each species is easily recognized by a unique combination of features in its external morphology and copulatory apparatus. The two new species of Girardia show a restricted distribution, even the troglophile, and occur in caves without legal protection. Therefore, they must be considered as vulnerable organisms in a conservation context. PMID:27394369

  16. Isolation of Sarcocystis falcatula from the South American opossum (Didelphis albiventris) from Argentina.

    PubMed

    Dubey, J P; Venturini, L; Venturini, C; Basso, W; Unzaga, J

    1999-10-15

    Sarcocystis sporocysts from the intestines of four opossums (Didelphis albiventris) from Argentina were identified as Sarcocystis falcatula based on schizogonic stages and pathogenicity to budgerigars (Melopsittacus undulatus). Seven budgerigars fed sporocysts from the opossum feces died of acute sarcocystosis 8, 9, 11, 12, and 14 days after inoculation. Schizonts and merozoites found in the lungs and other organs of the budgerigars were identified as S. falcatula based on structure and immunoreactivity with S. falcatula-specific antibody. Sarcocystis falcatula was also isolated in bovine monocyte cell cultures inoculated with lung tissue from a budgerigar that died nine days after ingesting sporocysts. Two budgerigars inoculated subcutaneously with 1,000,000 culture-derived S. falcatula died 11 and 12 days post-inoculation. This is the first report of S. falcatula infection in South America. PMID:10536981

  17. Interplay between metabolic rate and diet quality in the South American fox, Pseudalopex culpaeus.

    PubMed

    Silva, Sergio I; Jaksic, Fabian M; Bozinovic, Francisco

    2004-01-01

    We studied the metabolic costs associated with the ingestion of peppertree fruits (Schinus molle) in the culpeo fox, Pseudalopex culpaeus, the second largest canid in South America. Throughout its range of distribution, this fox feeds on rodents and other small vertebrates, and also on peppertree fruits, which represent 98% of total fruits consumed in semiarid Chile. Peppertree contains a high diversity of phytochemicals. Foxes feeding on diets containing rats and peppertree fruits (mixed diets) exhibited a 98.9% increase in basal rate of metabolism when compared to rat-acclimated foxes. Thus, acute ingestion of chemically defended fruits has an energetic cost for the fox, reflected in higher values of basal metabolism. Increased metabolic rates may be associated with increased protein synthesis for detoxification and for tissue repair, including the production of biotransformation enzymes. PMID:14720588

  18. Spacebased Observations of Oceanic Influence on the Annual Variation of South American Water Balance

    NASA Technical Reports Server (NTRS)

    Liu, W. Timothy; Xie, Xiaosu; Tang, Wenqing; Zlotnicki, Victor

    2006-01-01

    The mass change of South America (SA) continent measured by the Gravity Recovery and Climate Experiment (GRACE) imposes a constraint on the uncertainties in estimating the annual variation of rainfall measured by Tropical Rain Measuring Mission (TRMM) and ocean moisture influx derived from QuikSCAT data. The approximate balance of the mass change rate with the moisture influx less climatological river discharge, in agreement with the conservation principle, bolsters not only the credibility of the spacebased measurements, but supports the characterization of ocean's influence on the annual variation of continental water balance. The annual variation of rainfall is found to be in phase with the mass change rate in the Amazon and the La Plata basins, and the moisture advection across relevant segments of the Pacific and Atlantic coasts agrees with the annual cycle of rainfall in the two basins and the Andes mountains.

  19. 3D simulation of floral oil storage in the scopa of South American insects

    NASA Astrophysics Data System (ADS)

    Ruettgers, Alexander; Griebel, Michael; Pastrik, Lars; Schmied, Heiko; Wittmann, Dieter; Scherrieble, Andreas; Dinkelmann, Albrecht; Stegmaier, Thomas; InstituteNumerical Simulation Team; Institute of Crop Science; Resource Conservation Team; Institute of Textile Technology; Process Engineering Team

    2014-11-01

    Several species of bees in South America possess structures to store and transport floral oils. By using closely spaced hairs at their back legs, the so called scopa, these bees can absorb and release oil droplets without loss. The high efficiency of this process is a matter of ongoing research. Basing on recent x-ray microtomography scans from the scopa of these bees at the Institute of Textile Technology and Process Engineering Denkendorf, we build a three-dimensional computer model. Using NaSt3DGPF, a two-phase flow solver developed at the Institute for Numerical Simulation of the University of Bonn, we perform massively parallel flow simulations with the complex micro-CT data. In this talk, we discuss the results of our simulations and the transfer of the x-ray measurement into a computer model. This research was funded under GR 1144/18-1 by the Deutsche Forschungsgemeinschaft (DFG).

  20. Characterization and classification of South American land cover types using satellite data

    NASA Technical Reports Server (NTRS)

    Townshend, J. R. G.; Justice, C. O.; Kalb, V.

    1987-01-01

    Various methods are compared for carrying out land cover classifications of South America using multitemporal Advanced Very High Resolution Radiometer data. Fifty-two images of the normalized difference vegetation index (NDVI) from a 1-year period are used to generate multitemporal data sets. Three main approaches to land cover classification are considered, namely the use of the principal components transformed images, the use of a characteristic curves procedure based on NDVI values plotted against time, and finally application of the maximum likelihood rule to multitemporal data sets. Comparison of results from training sites indicates that the last approach yields the most accurate results. Despite the reliance on training site figures for performance assessment, the results are nevertheless extremely encouraging, with accuracies for several cover types exceeding 90 per cent.

  1. THE RELATIONS OF THE NORTH AMERICAN FLORA TO THAT OF SOUTH AMERICA.

    PubMed

    Bray, W L

    1900-11-01

    Reviewing the floral relations of North and South America as illustrated in the foregoing instances, we may say that the phenomena of distribution agree fairly with the record of physical conditions which have succeeded each other and those which still exist, and upon which we might almost a priori have predicted an analogous set of distribution phenomena. In this relationship we may distinguish three categories of distribution: (1) Those due to the conditions of human civilization, commerce, etc. This has resulted in placing the same species in similar regions of both continents, as, for example, Fagonia cretica in Lower California and Chile; Munroa squarrosa, western plains of North America, plains of Argentine and high plateaus of Chile and Bolivia; Frankenia grandiflora, Southern California and Arizona, coast lands of Chile; Oxytheca dendroidea, Lastarricea chilensis, and Chorizanthe comrnmissuralis, all in Southern California and Western Chile. (2) Those due to the operation of natural causes acting unde present conditions of climate, geology, etc. Under this head may be cited such species as sida leprosa, hastata, anomala, Cienfugosia sulphurea, Spergulariaplattensis and, in general, elements of Gulf zone distribution; also certain elements which still find a pathway along the continental axis, including some alpine and mountain xerophilous genera. (3) The third category of distribution would include those phenomena due to geological and climatic changes acting through long periods. Under this head are included the elements of greatest significance in the relationsip of the North and South America floras. The endemic boreal flora of the Andes, the equally endemic boreal flora of the Mexican Cordilleras, and genera with sharply distinct species or sub-genera in the arid extra-tropical regions of both continents, which may be called remnant elements. PMID:17832120

  2. Simulation of late Cenozoic South American flat-slab subduction using geodynamic models with data assimilation

    NASA Astrophysics Data System (ADS)

    Hu, Jiashun; Liu, Lijun; Hermosillo, Armando; Zhou, Quan

    2016-03-01

    The formation mechanisms of flat slabs in South America remain unclear. To quantitatively evaluate the earlier proposed mechanisms, we simulate the post-100 Ma subduction history below South America using 4-D geodynamic models by progressively incorporating plate kinematics, seafloor ages and key tectonic features including the buoyant oceanic crust, continental cratons, oceanic plateaus (i.e. the inferred Inca plateau, subducting Nazca Ridge and Juan Fernandez Ridge), as well as deformable trench profiles according to recent geological reconstructions. We find that, in the absence of an overriding plate and subducting buoyancy features, the seafloor age affects slab dip angle by controlling the slab's mechanical strength (i.e., the resistance to bending) and negative buoyancy (integrated positive density anomaly that enhances bending). Our models show that slab strength dominates its buoyancy at age >30 Ma and the opposite for younger ages. The existence of a thick overriding plate reduces the slab dip by increasing dynamic suction, and individual cratonic roots further lead to along-trench variations of dip angle reduction. While dynamic suction from the overriding plate generates a permanent reduction of the long-wavelength slab dip angle, it is the final addition of subducting oceanic plateau and aseismic ridges that produces the transient and localized flat-slabs as observed. These results suggest that all mechanisms except the buoyancy features affect the slab dip only at large spatial scales. Our best-fit model with all the above tectonic features included provides a good match to both the upper mantle Benioff zones and the temporal evolution of volcanic arcs since the mid-Miocene. The imperfect match of the Peruvian flat-slab is likely associated with the uncertain 3-D configuration of the Amazonian craton.

  3. Southern Oscillation Signal in South American Palaeoclimatic Data of the Last 7000 Years

    NASA Astrophysics Data System (ADS)

    Martin, Louis; Fournier, Marc; Mourguiart, Philippe; Sifeddine, Abdelfatah; Turcq, Bruno; Flexor, Jean-Marie; Absy, Maria Lucia

    1993-05-01

    During strong El Niño events, rainfall anomalies and changes in wind patterns are observed in different regions of South America. Along the central Brazilian coast, during the 1983 El Niño year, the frontal systems were blocked to the south, provoking a reversal of the longshore sand transport. Long-duration reversals of longshore transport were also recorded in Holocene beach-ridge terraces from the Rio Doce coastal plain. This led to the formulation of a model relating these reversals of longshore transport to El Niño-like conditions. El Niño-like conditions are past average climate situations that generate the same perturbations as the strong El Niño events observed during the last decade. They are likely to correspond to the long-duration low phase of the Southern Oscillation. To confirm this hypothesis we compared the Holocene beach-ridge record with other palaeoenvironmental records from regions where strong El Niño events would have a substancial signal as well: (1) water-level fluctuations of Lake Titicaca, (2) a pollen and sediment record in an eastern Amazonian lake, (3) changes of the Rio Xingu discharge in eastern Amazonia, and (4) variations of sand supply at the Rio Piura and Rio Chira outlets in the Sechura Desert. The occurrences of El Niño-like conditions were numerous before 3900-3600 yr B.P., absent between 39003600 and 2800-2500 yr B.P., and infrequent after 2800-2500 yr B.P.

  4. Reconstruction of multiple tectonic events in continental margins by integrated tectonostratigraphic and geochronological analysis: the Mesozoic to Paleogene Caribbean-South American interaction in northeastern Colombia

    NASA Astrophysics Data System (ADS)

    Cardona, Agustin; Montes, Camilo; Bayona, German; Valencia, Victor; Ramirez, Diego; Zapata, Sebastian; Lara, Mario; Lopez-Martinez, Margarita; Thomson, Stuart; Weber, Marion

    2013-04-01

    Although the older record and successive tectonic scenarios experienced by a continental margin is commonly fragmentary, integrated field, petrological and geochronological analysis can reconstruct the long term tectonic evolution of continental margins and characterized major controls on the orogenic style. We present new geochronological constraints from igneous and low to very low grade metasedimentary rocks from the Caribbean continental margin of northeastern Colombia (Guajira region) in order to reconstruct the different tectonic events recorded by the margin before, during and following the arc-continent collision with the front of the Caribbean plate. Zircon U-Pb LA-ICP-MS geochronology results from leucogranites associated with garnet amphibolites, tonalites and volcanic rocks that made the continental basement of northeastern Colombia reveals and Early to Middle Mesozoic tectonic activity with peaks at ca. 220-230 Ma and 170-180 Ma. This magmatic record is related to a collisional belt link to the final agglutination of Pangea and was followed by an overimposed far field back-arc setting associated to the subduction of the Pacific (Farrallon) plate under the Pangea supercontinent. Muscovite and biotite Ar-Ar geochronology from basement rocks and low grade Mesozoic metasediments also reveals the existence of Middle Jurassic to Early Cretaceous thermal events link to the final opening of the proto-Caribbean ocean. The South American continental margin was subsequently affected by an arc-continent collisional event with the front of the Caribbean plate. This event is recorded by the growth of a Banda-type collisional melange that mixed South American continental margin sediments with mafic and ultramafic blocks of intra-oceanic arc origin, the formation of a coherent metasedimentary belt also made of South American margin sediments, and the mylonitization of the continental basement. Ar-Ar temporal constraints on the low grade metasedimentary rocks and

  5. Discovery of South American suckermouth armored catfishes (Loricariidae, Pterygoplichthys spp.) in the Santa Fe River drainage, Suwannee River basin, USA

    USGS Publications Warehouse

    Nico, Leo G.; Butt, Peter L.; Johnston, Gerald R.; Jelks, Howard L.; Kail, Matthew; Walsh, Stephen J.

    2012-01-01

    We report on the occurrence of South American suckermouth armored catfishes (Loricariidae) in the Suwannee River basin, southeastern USA. Over the past few years (2009-2012), loricariid catfishes have been observed at various sites in the Santa Fe River drainage, a major tributary of the Suwannee in the state of Florida. Similar to other introduced populations of Pterygoplichthys, there is high likelihood of hybridization. To date, we have captured nine specimens (270-585 mm, standard length) in the Santa Fe River drainage. One specimen taken from Poe Spring best agrees with Pterygoplichthys gibbiceps (Kner, 1854) or may be a hybrid with either P. pardalis or P. disjunctivus. The other specimens were taken from several sites in the drainage and include seven that best agree with Pterygoplichthys disjunctivus (Weber, 1991); and one a possible P. disjunctivus x P. pardalis hybrid. We observed additional individuals, either these or similar appearing loricariids, in Hornsby and Poe springs and at various sites upstream and downstream of the long (> 4 km) subterranean portion of the Santa Fe River. These specimens represent the first confirmed records of Pterygoplichthys in the Suwannee River basin. The P. gibbiceps specimen represents the first documented record of an adult or near adult of this species in open waters of North America. Pterygoplichthys disjunctivus or its hybrids (perhaps hybrid swarms) are already abundant and widespread in other parts of peninsular Florida, but the Santa Fe River represents a northern extension of the catfish in the state. Pterygoplichthys are still relatively uncommon in the Santa Fe drainage and successful reproduction not yet documented. However, in May 2012 we captured five adult catfish (two mature or maturing males and three gravid females) from a single riverine swallet pool. One male was stationed at a nest burrow (no eggs present). To survive the occasional harsh Florida winters, these South American catfish apparently use

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

    PubMed

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

    2013-09-01

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

  7. The South American opossum, Didelphis marsupialis, from Brazil as another definitive host for Sarcocystis speeri Dubey and Lindsay, 1999.

    PubMed

    Dubey, J P; Kerber, C E; Lindsay, D S; Kasai, N; Pena, H F

    2000-12-01

    The North American opossum, Didelphis virginiana, is a definitive host for at least 3 species of Sarcocvstis: S. falcatula Stiles 1983, S. neurona Dubey, Davis, Speer, Bowman, de Lahunta, Granstrom, Topper, Hamir, Cummings, Suter 1991, and S. speeri Dubey and Lindsay 1999. In order to identify species of Sarcocystis in the South American opossum, D. inarsupialis, Sarcocystis sporocysts from the intestines of a naturally infected opossum (D. marsupialis) from Brazil were fed to 4 gamma-interferon knockout (KO) mice, a nude mouse, and 2 budgerigars (Melopsittacus undulatus). All 4 KO mice became ill and 1 died 42 days post-feeding (p.f.) of sporocysts, 1 was killed 44 days p.f. because of neurological signs, and 2 were killed 52 and 53 days p.f. because of abnormal gaits. Numerous sarcocysts were seen in the skeletal muscles of all 4 KO mice and they were structurally identical to S. speeri seen in KO mice fed sporocysts from D. virginiana from the United States and D. albiventris from Argentina. The nude mouse was killed 41 days p.f. because it appeared weak; schizonts were seen in sections of its liver and sarcocysts were seen in sections of skeletal muscles. Sarcocystis speeri was cultured in bovine turbinate cells inoculated with liver homogenate from this mouse. Sarcocystis neurona was not demonstrable in tissues of mice. The two budgerigars remained asymptomatic and S. falcatula was not found in their tissues when they were killed 29 days p.i. This is the first report of S. speeri from D. marsupialis. PMID:11155929

  8. The Precarious Health of Young Mexican American Men in South Texas, Cameron County Hispanic Cohort, 2004–2015

    PubMed Central

    Vatcheva, Kristina P.; Griffith, Derek M.; Reininger, Belinda M.; Beretta, Laura; Fallon, Michael B.; McCormick, Joseph B.; Fisher-Hoch, Susan P.

    2016-01-01

    Introduction Hispanic men have higher rates of illness and death from various chronic conditions than do non-Hispanic men. We aimed to characterize the health of Mexican American men living on the US–Mexico border in South Texas and elucidate indications of chronic disease in young men. Methods We sampled all male participants from the Cameron County Hispanic Cohort, an ongoing population-based cohort of Mexican Americans in Brownsville, Texas. We calculated descriptive statistics and stratified the sample into 3 age groups to estimate the prevalence of sociodemographic, behavioral, and clinical factors by age group and evaluated differences between age groups. Results Obesity prevalence was approximately 50% across all age groups (P = .83). Diabetes prevalence was high overall (26.8%), and 16.9% (95% confidence interval [CI], 10.1%–23.8%) of men younger than 35 had diabetes. More than 70% of these young men had elevated liver enzymes, and mean values of aspartate aminotransferase were significantly higher in younger men (45.0 u/L; 95% CI, 39.5–50.6 u/L) than in both older age groups. Less than 20% of young men had any form of health insurance. Current smoking was higher in young men than in men in the other groups, and the rate was higher than the national prevalence of current smoking among Hispanic men. Conclusions We suggest a need for obesity and diabetes prevention programs and smoking cessation programs for men in this region. Opportunities exist to expand current intervention programs and tailor them to better reach this vulnerable population of young Hispanic men. Elevated liver enzymes in men younger than 35 suggest a substantial burden of liver abnormalities, a finding that warrants further study. PMID:27560721

  9. The Caribbean-South American plate boundary at 65°W: Results from wide-angle seismic data

    NASA Astrophysics Data System (ADS)

    Bezada, M. J.; Magnani, M. B.; Zelt, C. A.; Schmitz, M.; Levander, A.

    2010-08-01

    We present the results of the analysis of new wide-angle seismic data across the Caribbean-South American plate boundary in eastern Venezuela at about 65°W. The ˜500 km long profile crosses the boundary in one of the few regions dominated by extensional structures, as most of the southeastern Caribbean margin is characterized by the presence of fold and thrust belts. A combination of first-arrival traveltime inversion and simultaneous inversion of PmP and Pn arrivals was used to develop a P wave velocity model of the crust and the uppermost mantle. At the main strike-slip fault system, we image the Cariaco Trough, a major pull-apart basin along the plate boundary. The crust under the Southern Caribbean Deformed Belt exhibits a thickness of ˜15 km, suggesting that the Caribbean Large Igneous Province extends to this part of the Caribbean plate. The velocity structures of basement highs and offshore sedimentary basins imaged by the profile are comparable to those of features found in other parts of the margin, suggesting similarities in their tectonic history. We do not image an abrupt change in Moho depth or velocity structure across the main strike-slip system, as has been observed elsewhere along the margin. It is possible that a terrane of Caribbean island arc origin was accreted to South America at this site and was subsequently bisected by the strike-slip fault system. The crust under the continental portion of the profile is thinner than observed elsewhere along the margin, possibly as a result of thinning during Jurassic rifting.

  10. Overview of the South American Biomass Burning Analysis (SAMBBA) field experiment in Brazil during Sept - Oct 2012

    NASA Astrophysics Data System (ADS)

    Johnson, Ben; Haywood, Jim; Longo, Karla; Coe, Hugh; Artaxo, Paulo; Morgan, William; Freitas, Saulo

    2013-04-01

    The South American Biomass Burning Analysis (SAMBBA) is an international research project investigating the impacts of biomass burning emissions on climate, air quality and numerical weather prediction over South America. The project involves a combination of measurements and modelling activities to assess the role of biomass burning and biogenic emissions in the earth system. This international collaboration has been led by a partnership between the Met Office, the Brazilian National Institute for Space research (INPE), the University of Sao Paulo, and a consortium of UK Universities. The measurement program was headed by the deployment of UK's Facility for Airborne Atmospheric Measurements (FAAM) BAe-146 research aircraft over Brazil during the dry season of September - October 2012. This was co-ordinated with ground-based measurements operated by the University of Sao Paulo and INPE. This successful field experiment now provides an excellent source of observations to build our understanding of biomass burning processes and improve model simulations of biomass burning aerosols and their interactions with biogenic emissions, atmospheric chemistry, clouds, radiation, and the terrestrial biosphere. This talk will summarise the field experiment, including the aircraft measurements and ground-based observations made during the dry season of 2012. Preliminary results will highlight the range of biomass burning and biogenic emissions observed from tropical forest, deforested zones and scrub-land. Case studies will also show infra-red camera images of fire radiative output, the evolution of large smoke plumes and the variable composition of background aerosol and extensive haze layers across the region. The lidar data and aircraft profiles also highlight the prevalence of elevated aerosol layers observed at altitudes of 3 - 7km, presumed to be detrainment from large smoke plumes, pyrocumulus and mid-level convection. The ground-based observations also highlight the

  11. Real time earthquake information and tsunami estimation system for Indonesia, Philippines and Central-South American regions

    NASA Astrophysics Data System (ADS)

    Pulido Hernandez, N. E.; Inazu, D.; Saito, T.; Senda, J.; Fukuyama, E.; Kumagai, H.

    2015-12-01

    Southeast Asia as well as Central-South American regions are within the most active seismic regions in the world. To contribute to the understanding of source process of earthquakes the National Research Institute for Earth Science and Disaster Prevention NIED maintains the international seismic Network (ISN) since 2007. Continuous seismic waveforms from 294 broadband seismic stations in Indonesia, Philippines, and Central-South America regions are received in real time at NIED, and used for automatic location of seismic events. Using these data we perform automatic and manual estimation of moment tensor of seismic events (Mw>4.5) by using the SWIFT program developed at NIED. We simulate the propagation of local tsunamis in these regions using a tsunami simulation code and visualization system developed at NIED, combined with CMT parameters estimated by SWIFT. The goals of the system are to provide a rapid and reliable earthquake and tsunami information in particular for large seismic, and produce an appropriate database of earthquake source parameters and tsunami simulations for research. The system uses the hypocenter location and magnitude of earthquakes automatically determined at NIED by the SeisComP3 system (GFZ) from the continuous seismic waveforms in the region, to perform the automated calculation of moment tensors by SWIFT, and then carry out the automatic simulation and visualization of tsunami. The system generates maps of maximum tsunami heights within the target regions and along the coasts and display them with the fault model parameters used for tsunami simulations. Tsunami calculations are performed for all events with available automatic SWIFT/CMT solutions. Tsunami calculations are re-computed using SWIFT manual solutions for events with Mw>5.5 and centroid depths shallower than 100 km. Revised maximum tsunami heights as well as animation of tsunami propagation are also calculated and displayed for the two double couple solutions by SWIFT

  12. Genetic, geographic, and linguistic variation among South American Indians: possible sex influence.

    PubMed

    Fagundes, Nelson J R; Bonatto, S L; Callegari-Jacques, S M; Salzano, F M

    2002-01-01

    To better understand the relationship between genetic variability, geographical distance, and linguistic affiliation in South Amerinds, and to elucidate whether the migration rate is the same for both sexes, spatial autocorrelation, Mantel's test, and F(ST) analyses were performed in four sets of populations and alleles (group 1: 48 populations, 12 alleles; group 2: 16 (all belonging to the Tupi linguistic group) and 12; group 3: 21 and 17; and group 4: 28 and 4 haplotypes). Groups 1-3 included blood group and protein (i.e., serum protein, red cell enzymes, and immunoglobulin systems), while group 4 was concerned with mitochondrial DNA (mtDNA) only. The latter set was also subjected to a molecular analysis of variance (AMOVA) evaluation. The frequencies of statistically significant correlograms were lower than those obtained in other populations when the blood groups and protein systems were considered, but 3 of the 4 mtDNA haplogroups gave suggestions of population structure. The variability in this organelle is also significantly correlated with language when geography is held constant. Migration per generation is generally low, but higher estimates were obtained for females. The AMOVA results suggest that populations whose members speak the same language are genetically homogeneous and may be viewed as the ultimate evolutionary unit at this level of analysis. PMID:11748563

  13. Polychlorinated biphenyls in eggs and chlorioallantoic membranes of American alligators (Alligator mississippiensis) from coastal South Carolina

    SciTech Connect

    Cobb, G.P.; Wood, P.D.; O`Quinn, M.

    1997-07-01

    Assessing chemical exposure in threatened or endangered wildlife species presents unique analytical problems. Chorioallantoic membranes (CAMs) have been proposed as surrogate tissues for evaluation of polychlorinated biphenyl (PCB) exposure in oviparous species. Research was undertaken to determine the extent of PCB accumulation in alligators (Alligator mississippiensis) at sites along the coast of South Carolina and to evaluate the utility of CAMs as surrogate tissues for determining PCB concentrations in whole alligator eggs. Polychlorinated biphenyls were found in eggs and CAMs of alligators from both sites examined. Concentrations of PCBs were higher in CAMs (p = 0.02) and eggs (p = 0.001) from sites known to contain chlorinated hydrocarbons than from more pristine sites. Total PCBs partitioned predictably (r{sup 2} > 0.59; p < 0.02) between egg and CAM tissues indicating the utility of CAMs to serve as surrogate tissues when comparing total PCB concentrations in whole eggs. Tetrachloro through octachloro biphenyl homologues and total PCBs in CAMs from reference areas were correlated with concentrations of these homologues in eggs. At contaminated sites, total PCB concentrations in CAMs were correlated with total PCB concentrations in eggs.

  14. Effect of bite force and diet composition on craniofacial diversification of Southern South American human populations.

    PubMed

    Menéndez, Lumila; Bernal, Valeria; Novellino, Paula; Perez, S Ivan

    2014-09-01

    Ecological factors can be important to shape the patterns of morphological variation among human populations. Particularly, diet plays a fundamental role in craniofacial variation due to both the effect of the nutritional status-mostly dependent on the type and amount of nutrients consumed-on skeletal growth and the localized effects of masticatory forces. We examine these two dimensions of diet and evaluate their influence on morphological diversification of human populations from southern South America during the late Holocene. Cranial morphology was measured as 3D coordinates defining the face, base and vault. Size, form, and shape variables were obtained for 474 adult individuals coming from 12 samples. Diet composition was inferred from carious lesions and δ(13) C data, whereas bite forces were estimated using traits of main jaw muscles. The spatial structure of the morphological and ecological variables was measured using correlograms. The influence of diet composition and bite force on morphometric variation was estimated by a spatial regression model. Cranial variation and diet composition display a geographical structure, while no geographical pattern was observed in bite forces. Cranial variation in size and form is significantly associated with diet composition, suggesting a strong effect of systemic factors on cranial growth. Conversely, bite forces do not contribute significantly to the pattern of morphological variation among the samples analyzed. Overall, these results show that an association between diet composition and hardness cannot be assumed, and highlight the complex relationship between morphological diversification and diet in human populations. PMID:24985052

  15. The hibernating South American marsupial, Dromiciops gliroides, displays torpor-sensitive microRNA expression patterns

    PubMed Central

    Hadj-Moussa, Hanane; Moggridge, Jason A.; Luu, Bryan E.; Quintero-Galvis, Julian F.; Gaitán-Espitia, Juan Diego; Nespolo, Roberto F.; Storey, Kenneth B.

    2016-01-01

    When faced with adverse environmental conditions, the marsupial Dromiciops gliroides uses either daily or seasonal torpor to support survival and is the only known hibernating mammal in South America. As the sole living representative of the ancient Order Microbiotheria, this species can provide crucial information about the evolutionary origins and biochemical mechanisms of hibernation. Hibernation is a complex energy-saving strategy that involves changes in gene expression that are elicited in part by microRNAs. To better elucidate the role of microRNAs in orchestrating hypometabolism, a modified stem-loop technique and quantitative PCR were used to characterize the relative expression levels of 85 microRNAs in liver and skeletal muscle of control and torpid D. gliroides. Thirty-nine microRNAs were differentially regulated during torpor; of these, 35 were downregulated in liver and 11 were differentially expressed in skeletal muscle. Bioinformatic analysis predicted that the downregulated liver microRNAs were associated with activation of MAPK, PI3K-Akt and mTOR pathways, suggesting their importance in facilitating marsupial torpor. In skeletal muscle, hibernation-responsive microRNAs were predicted to regulate focal adhesion, ErbB, and mTOR pathways, indicating a promotion of muscle maintenance mechanisms. These tissue-specific responses suggest that microRNAs regulate key molecular pathways that facilitate hibernation, thermoregulation, and prevention of muscle disuse atrophy. PMID:27090740

  16. High Frequency of Chlamydia trachomatis Mixed Infections Detected by Microarray Assay in South American Samples

    PubMed Central

    Gallo Vaulet, Lucía; Entrocassi, Carolina; Portu, Ana I.; Castro, Erica; Di Bartolomeo, Susana; Ruettger, Anke; Sachse, Konrad; Rodriguez Fermepin, Marcelo

    2016-01-01

    Chlamydia trachomatis is one of the most common sexually transmitted infections worldwide. Based on sequence variation in the ompA gene encoding the major outer membrane protein, the genotyping scheme distinguishes 17 recognized genotypes, i.e. A, B, Ba, C, D, Da, E, F, G, H, I, Ia, J, K, L1, L2, and L3. Genotyping is an important tool for epidemiological tracking of C. trachomatis infections, including the revelation of transmission pathways and association with tissue tropism and pathogenicity. Moreover, genotyping can be useful for clinicians to establish the correct treatment when LGV strains are detected. Recently a microarray assay was described that offers several advantages, such as rapidity, ease of standardization and detection of mixed infections. The aim of this study was to evaluate the performance of the DNA microarray-based assay for C. trachomatis genotyping of clinical samples already typed by PCR-RFLP from South America. The agreement between both typing techniques was 90.05% and the overall genotype distribution obtained with both techniques was similar. Detection of mixed-genotype infections was significantly higher using the microarray assay (8.4% of cases) compared to PCR-RFLP (0.5%). Among 178 samples, the microarray assay identified 10 ompA genotypes, i.e. D, Da, E, F, G, H, I, J, K and L2. The most predominant type was genotype E, followed by D and F. PMID:27082962

  17. Redescription of Spirura guianensis (Nematoda: Spiruridae) from a rare South American Gracile Opossum.

    PubMed

    Torres, E J Lopes; Maldonado, A; Anjos, D H da Silva; de Souza, W; Miranda, K

    2015-10-01

    Spirura genus Blanchard, 1849 comprise of nematode parasites that infect primate and marsupial species. Although several taxonomical studies have shown that the infection by this species occurs primarily in the esophagus of primates, evidence for the occurrence of these parasites in other hosts (marsupials, rodents and bats) has become the subject of investigation by several groups. In this work, we describe the presence of Spirura guianensis Ortlepp, 1924 in the marsupial Gracilinanus agilis (Marsupialia: Didelphidae) found in the Pantanal of Mato Grosso do Sul state of Brazil. Structural characteristics of this nematode were identified using light microscopy (bright field and fluorescence stereomicroscopy) and scanning electron microscopy (SEM) approaches. Details of the surface topography such as cephalic projections, ventral boss, details of the caudal papillae and cuticular ornamentations were shown, providing taxonomic characteristics that may help in the establishment of diagnostic protocols. In addition, the presence of this species in a new host and new geographical area of Brazil provide grounds for a revision on the distribution of S. guianensis in South America. PMID:26187357

  18. Future Deforestation in the Amazon and Consequences for South American Climate

    NASA Astrophysics Data System (ADS)

    Swann, A. L. S.; Longo, M.; Knox, R. G.; Lee, E.; Moorcroft, P. R.

    2014-12-01

    Ongoing agricultural expansion in Amazonia and the surrounding areas of Brazil is expected to continue over the next several decades as global food demand increases. The transition of natural forest and cerrado ecosystems to pastureland and agricultural crops is predicted to create warmer and drier atmospheric conditions than the native vegetation. Using a coupled ecosystem- regional atmospheric model (ED-BRAMS) we investigate the impacts of predicted future land use on the climate of South America. We find that the climate response in our model is consistent with expectations - with drier conditions resulting from deforestation, however the changes in precipitation are moderate. Local drying is driven primarily by decreases in evapotranspiration associated with the loss of leaf area, and coincident increases in runoff. Significant consistent changes are seen in convectively available potential energy and convective inhibition suggesting that the decrease in surface latent heat flux is indeed leading to a drier atmosphere, however these changes occur at mean state values that are already very favorable for convection leading to little change in precipitation. If large-scale circulation changes occur in the future to push the atmosphere over the Amazon towards a drier state as predicted by the CMIP3 and CMIP5 archives, we postulate that land use change could accelerate the movement across a convective threshold.

  19. Variability in land water storage from GRACE and ENVISAT, and rainfall in South American river basins

    NASA Astrophysics Data System (ADS)

    Xavier, L.; Cazenave, A.; Bonnet, M.; Rotunno, O.

    2008-12-01

    Previous work has demonstrated the capability of GRACE to capture important aspects of the hydrological cycle, in particular seasonal and interannual fluctuations in land water storage of large river basins. Part of this behaviour can be immediately assigned to seasonal/interannual fluctuations of precipitation. In this study, we investigate existing correlations between GRACE water storage (two GRACE products are used and compared, the GRGS and GSFC/Mascons solutions), ENVISAT-based surface water levels and precipitation data over four large river basins of South America (Orinoco, Amazon, Tocantins and Parana). At the seasonal time scale, precipitation and total water storage correlate well in the Parana basin, with a few weeks lag of storage with respect to forcing. Over the Amazon, Tocantins and Orinoco, the two variables also correlate well. But in some years, storage response to forcing is enhanced, suggesting that other terms of the water balance (e.g., runoff) play a significant role. To investigate this, discharge data at the most downstream stations in these river basins are analysed, while the water balance is studied using outputs of global hydrological models available over the same time span as GRACE data. We also analyse water level data from ENVISAT altimetry over the main rivers. Finally, we study the interannual connection between rainfall and water storage, using among others, Empirical Orthogonal Functions (EOF). Compared to the seasonal cycle, the interannual signal displays larger regional variability both in precipitation and water storage.

  20. The first South American sandownid turtle from the Lower Cretaceous of Colombia

    PubMed Central

    2015-01-01

    Sandownids are a group of Early Cretaceous-Paleocene turtles that for several decades have been only known by cranial and very fragmentary postcranial elements. Here I report and describe the most complete sandownid turtle known so far, including articulated skull, lower jaw and postcranial elements, from the Early Cretaceous (upper Barremian-lower Aptian, >120 Ma), Paja Formation, Villa de Leyva town, Colombia. The new Colombian sandownid is defined here as Leyvachelys cipadi new genus, new species and because of its almost identical skull morphology with a previously reported turtle from the Glen Rose Formation, Texas, USA, both are grouped in a single and officially (ICNZ rules) defined taxon. Phylogenetic analysis including L. cipadi supports once again the monophyly of Sandownidae, as belonging to the large and recently redefined Pan-Chelonioidea clade. The morphology of L. cipadi indicates that sandownids were not open marine turtles, but instead littoral to shallow marine durophagous dwellers. Leyvachelys cipadi not only constitutes the first record of sandowinds in South America, but also the earliest global record for the group. PMID:26713227

  1. The hibernating South American marsupial, Dromiciops gliroides, displays torpor-sensitive microRNA expression patterns.

    PubMed

    Hadj-Moussa, Hanane; Moggridge, Jason A; Luu, Bryan E; Quintero-Galvis, Julian F; Gaitán-Espitia, Juan Diego; Nespolo, Roberto F; Storey, Kenneth B

    2016-01-01

    When faced with adverse environmental conditions, the marsupial Dromiciops gliroides uses either daily or seasonal torpor to support survival and is the only known hibernating mammal in South America. As the sole living representative of the ancient Order Microbiotheria, this species can provide crucial information about the evolutionary origins and biochemical mechanisms of hibernation. Hibernation is a complex energy-saving strategy that involves changes in gene expression that are elicited in part by microRNAs. To better elucidate the role of microRNAs in orchestrating hypometabolism, a modified stem-loop technique and quantitative PCR were used to characterize the relative expression levels of 85 microRNAs in liver and skeletal muscle of control and torpid D. gliroides. Thirty-nine microRNAs were differentially regulated during torpor; of these, 35 were downregulated in liver and 11 were differentially expressed in skeletal muscle. Bioinformatic analysis predicted that the downregulated liver microRNAs were associated with activation of MAPK, PI3K-Akt and mTOR pathways, suggesting their importance in facilitating marsupial torpor. In skeletal muscle, hibernation-responsive microRNAs were predicted to regulate focal adhesion, ErbB, and mTOR pathways, indicating a promotion of muscle maintenance mechanisms. These tissue-specific responses suggest that microRNAs regulate key molecular pathways that facilitate hibernation, thermoregulation, and prevention of muscle disuse atrophy. PMID:27090740

  2. The first South American sandownid turtle from the Lower Cretaceous of Colombia.

    PubMed

    Cadena, Edwin

    2015-01-01

    Sandownids are a group of Early Cretaceous-Paleocene turtles that for several decades have been only known by cranial and very fragmentary postcranial elements. Here I report and describe the most complete sandownid turtle known so far, including articulated skull, lower jaw and postcranial elements, from the Early Cretaceous (upper Barremian-lower Aptian, >120 Ma), Paja Formation, Villa de Leyva town, Colombia. The new Colombian sandownid is defined here as Leyvachelys cipadi new genus, new species and because of its almost identical skull morphology with a previously reported turtle from the Glen Rose Formation, Texas, USA, both are grouped in a single and officially (ICNZ rules) defined taxon. Phylogenetic analysis including L. cipadi supports once again the monophyly of Sandownidae, as belonging to the large and recently redefined Pan-Chelonioidea clade. The morphology of L. cipadi indicates that sandownids were not open marine turtles, but instead littoral to shallow marine durophagous dwellers. Leyvachelys cipadi not only constitutes the first record of sandowinds in South America, but also the earliest global record for the group. PMID:26713227

  3. Lessons learned for a more efficient knowledge and technology transfer to South American countries in the fields of solid waste and contaminated sites management.

    PubMed

    Bezama, Alberto; Szarka, Nóra; Navia, Rodrigo; Konrad, Odorico; Lorber, Karl E

    2007-04-01

    The present paper describes the development, performance and conclusions derived from three know-how and technology transfer projects to South American countries. The first project comprised a collaborative study by European and South American universities to find sustainable solutions for Chilean and Ecuadorian leather tanneries which had underachieving process performances. The second project consisted of investigations carried out in a Brazilian municipality to enhance its municipal solid waste management system. The final collaborative programme dealt with the initial identification, evaluation and registration of suspected contaminated sites in an industrial region of Chile. The detailed objectives, methods and procedures applied as well as the results and conclusions obtained in each of the three mentioned projects are presented, giving special attention to the organizational aspects and to the practical approach of each programme, concluding with their main advantages and disadvantages for identifying a set of qualitative and quantitative suggestions, and to establish transferable methods for future applications. PMID:17439050

  4. D2 Region of the 28S RNA Gene: A Too-Conserved Fragment for Inferences on Phylogeny of South American Triatomines.

    PubMed

    Guerra, Ana Letícia; Alevi, Kaio Cesar Chaboli; Banho, Cecília Artico; de Oliveira, Jader; da Rosa, João Aristeu; Vilela de Azeredo-Oliveira, Maria Tercília

    2016-09-01

    The brasiliensis complex is composed of five triatomine species, and different approaches suggest that Triatoma lenti and Triatoma petrochiae may be the new members. Therefore, this study sought to analyze the phylogenetic relationships within this complex by means of the D2 region of the 28S RNA gene, and to analyze the degree of polymorphism and phylogenetic significance of this gene for South American triatomines. Phylogenetic analysis by using sequence fragments of the D2 domain did not allow to perform phylogenetic inferences on species within the brasiliensis complex, because the gene alignment composed of a matrix with 37 specimens exhibited only two variable sites along the 567 base pairs used. Furthermore, if all South American species are included, only four variable sites were detected, reflecting the high degree of gene conservation. Therefore, we do not recommend the use of this gene for phylogenetic reconstruction for this group of Chagas disease vectors. PMID:27382073

  5. Phylogenetic relationships of the South American ground beetle subgenus Chilioperyphus Jeannel (Coleoptera: Carabidae: Trechinae: Bembidiini: Bembidion Latreille).

    PubMed

    Maddison, David R; Toledano, Luca; Sallenave, Soledad; Roig-Juñent, Sergio

    2013-01-01

    The boundaries and relationships of the ground beetle group Chilioperyphus Jeannel (a subgenus of the cosmopolitan genus Bembidion Latreille) are examined using DNA and morphological data. DNA sequence data from seven genes (six nuclear and one mitochondrial) indicates that Chiliopeiyphus (as newly defined) is monophyletic, and is related to the subgenera Antipetyphanes Jeannel and Plocanoperyphus Jeannel, within the South American Antiperyphanes Complex. Chilioperyphus includes two described species, B. iendocinum Jensen-Haarup and B. orregoi Germain. Beinbidion cassinense Roig-Juñent and Gianuca as well as Bembidion cuyanum Roig-Juñent and Scheibler, formerly placed in subgenus Chilioperyphus, are transferred to subgenus Antipetyphanes. Bembidion cuyanum is considered a junior synonym of B. hirtipes Jeannel. The male genitalia of Chilioperyphus is unique in having a very long flagellum that is folded twice, allowing it to fit much of its length within the walls of the median lobe. However, the brush sclerite and basal part of the flagellum are not contained within the median lobe, as they extend anterior to its base. PMID:26042310

  6. A Spectrophotometric Study of Plumage Color in the Eared Dove (Zenaida auriculata), the Most Abundant South American Columbiforme.

    PubMed

    Valdez, Diego Javier; Benitez-Vieyra, Santiago Miguel

    2016-01-01

    For birds, plumage color perception is critical in social interactions such as courtship, in both monochromatic and dichromatic species. In the Eared Dove (Zenaida auriculata), perhaps the most abundant South American Columbiforme, the plumage of males and females looks alike and both sexes share the same melanistic coloration with gray and pink tones. The aim of this study was therefore to determine whether evident sexual dichromatism exists in the plumage of the Eared Dove using a spectrophotometry technique in the avian-visible range (300-700 nm). The results of the classic colorimetric variables analysis (hue, chroma and brightness) show that males are in general brighter and have higher UV chroma values than females. The avian visual model points to differences in achromatic and chromatic levels between males and females in body regions possibly involved in sexual selection (e.g. the crown). The model also indicates chromatic or achromatic differences in body regions not subject to sexual selection such as the black spots on the wing coverts and white tail bands, both of which may be involved in intra- or inter-gender-specific communication. PMID:27213273

  7. Origin of increased terrigenous supply to the NE South American continental margin during Heinrich Stadial 1 and the Younger Dryas

    NASA Astrophysics Data System (ADS)

    Zhang, Yancheng; Chiessi, Cristiano M.; Mulitza, Stefan; Zabel, Matthias; Trindade, Ricardo I. F.; Hollanda, Maria Helena B. M.; Dantas, Elton L.; Govin, Aline; Tiedemann, Ralf; Wefer, Gerold

    2015-12-01

    We investigate the redistribution of terrigenous materials in the northeastern (NE) South American continental margin during slowdown events of the Atlantic Meridional Overturning Circulation (AMOC). The compilation of stratigraphic data from 108 marine sediment cores collected across the western tropical Atlantic shows an extreme rise in sedimentation rates off the Parnaíba River mouth (about 2°S) during Heinrich Stadial 1 (HS1, 18-15 ka). Sediment core GeoB16206-1, raised offshore the Parnaíba River mouth, documents relatively constant 143Nd/144Nd values (expressed as εNd(0)) throughout the last 30 ka. Whereas the homogeneous εNd(0) data support the input of fluvial sediments by the Parnaíba River from the same source area directly onshore, the increases in Fe/Ca, Al/Si and Rb/Sr during HS1 indicate a marked intensification of fluvial erosion in the Parnaíba River drainage basin. In contrast, the εNd(0) values from sediment core GeoB16224-1 collected off French Guiana (about 7°N) suggest Amazon-sourced materials within the last 30 ka. We attribute the extremely high volume of terrigenous sediments deposited offshore the Parnaíba River mouth during HS1 to (i) an enhanced precipitation in the catchment region and (ii) a reduced North Brazil Current, which are both associated with a weakened AMOC.

  8. Molecular assessment of the phylogeny and biogeography of a recently diversified endemic group of South American canids (Mammalia: Carnivora: Canidae)

    PubMed Central

    Tchaicka, Ligia; de Freitas, Thales Renato Ochotorena; Bager, Alex; Vidal, Stela Luengos; Lucherini, Mauro; Iriarte, Agustín; Novaro, Andres; Geffen, Eli; Garcez, Fabricio Silva; Johnson, Warren E.; Wayne, Robert K.; Eizirik, Eduardo

    2016-01-01

    Abstract To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus. PMID:27560989

  9. South American smoke coverage and flux estimations from the Fire Locating and Modeling of Burning Emissions (FLAMBE') system.

    NASA Astrophysics Data System (ADS)

    Reid, J. S.; Westphal, D. L.; Christopher, S. A.; Prins, E. M.; Gasso, S.; Reid, E.; Theisen, M.; Schmidt, C. C.; Hunter, J.; Eck, T.

    2002-05-01

    The Fire Locating and Modeling of Burning Emissions (FLAMBE') project is a joint Navy, NOAA, NASA and university project to integrate satellite products with numerical aerosol models to produce a real time fire and emissions inventory. At the center of the program is the Wildfire Automated Biomass Burning Algorithm (WF ABBA) which provides real-time fire products and the NRL Aerosol Analysis and Prediction System to model smoke transport. In this presentation we give a brief overview of the system and methods, but emphasize new estimations of smoke coverage and emission fluxes from the South American continent. Temporal and smoke patterns compare reasonably well with AERONET and MODIS aerosol optical depth products for the 2000 and 2001 fire seasons. Fluxes are computed by relating NAAPS output fields and MODIS optical depth maps with modeled wind fields. Smoke emissions and transport fluxes out of the continent can then be estimated by perturbing the modeled emissions to gain agreement with the satellite and wind products. Regional smoke emissions are also presented for grass and forest burning.

  10. Acupuncture for locomotor disabilities in a South American red-footed tortoise (Geochelone carbonaria) - a case report.

    PubMed

    Scognamillo-Szabó, Márcia Valéria Rizzo; Santos, André Luiz Quagliatto; Olegário, Maria Marlene Martins; Andrade, Mariana Batista

    2008-12-01

    The literature contains numerous reports of the effect of acupuncture on domestic or experimental animals, but only a few involving wild animals. This paper reports on acupuncture treatment for locomotor disabilities in a South American red-footed tortoise (Geochelone carbonaria, SPIX, 1824), an endangered land tortoise found in Brazils Cerrado region. The animal was captured and kept in an aquatic pen, subsequently developing respiratory symptoms and locomotor disabilities. The respiratory symptoms resolved in response to antibiotic treatment. However, despite the use of nutritional supplements, the motor symptoms remained unchanged. After 16 months, the tortoise was given six acupuncture sessions. No other changes were made to its environment or management. The location of the acupuncture points was transposed from canine charts. After acupuncture, the animals motor functions, which had remained unchanged during the preceding 16 months, were restored, enabling it to eat and walk unaided. The improvement persisted during 18 months follow up. The transposition of acupuncture points from canine charts is a viable alternative for chelonians. PMID:19098697

  11. Assessing European Egg Parasitoids as a Mean of Controlling the Invasive South American Tomato Pinworm Tuta absoluta

    PubMed Central

    Chailleux, Anaïs; Desneux, Nicolas; Seguret, Julien; Do Thi Khanh, Hong; Maignet, Pascal; Tabone, Elisabeth

    2012-01-01

    The South American tomato pinworm (Tuta absoluta) has recently invaded Europe and is rapidly spreading in the Afro-Eurasian continent where it is becoming a major pest on tomato crops. Laboratory tests were undertaken to evaluate the potential of 29 European strains of Trichogramma parasitoids to control T. absoluta. In addition to the host itself, the host plant (tomato) was used during the laboratory tests in order to increase the chance of selecting the best parasitoid strains. Trichogramma females were placed with T. absoluta eggs on a tomato leaflet in tubes. We compared the parasitism of T. absoluta by the various Trichogramma species tested to the Trichogramma species currently commercially available for the pest control in Europe, i.e. Trichogramma achaeae. Thereafter, the more promising strains were tested on a larger scale, in mesocosm (i.e. cages in greenhouses) and in greenhouse compartments to evaluate efficiency of laboratory selected strains under cropping conditions. The most efficient strain from the laboratory screening trials did not perform as efficiently under the greenhouse conditions. We discuss differences in parasitism levels among species and strains and among the different scales tested in the experiments, as well as implications of these results for further screening for biocontrol agents. PMID:23144727

  12. Germs and Jim Crow: the impact of microbiology on public health policies in progressive era American South.

    PubMed

    Patterson, Andrea

    2009-01-01

    Race proved not merely a disadvantage in securing access to prompt and appropriate medical care, but often became a life and death issue for blacks in the American South during the early decades of the twentieth century. This article investigates the impact some of the new academic disciplines such as anthropology, evolutionary biology, racially based pathology and genetics had in promoting scientific racism. The disproportionately high morbidity and mortality rates among blacks were seen as a consequence of inherent racial deficiencies that rendered any attempt to ameliorate their situation as futile. While the belief in a different pathology in blacks initially deterred most health officials from taking any action, advances in medicine and microbiology, in particular the germ theory, stirred a variety of responses out of sheer self preservation, as fears among whites at the first sign of an epidemic initiated sporadic and limited actions. Ironically, in an era of deepening scientific racism, public health initiatives based on a better understanding of disease causing microorganisms, gradually improved black health. However, some public health measures were hijacked by eugenicists and racists and, rather than addressing the ill health of blacks, public health policy complied with the new laws of heredity by promoting drastic measures such as involuntary sterilization or even abortion. This further complicated the strained relationship between southern blacks and health care professionals and effected ongoing distrust towards public healthcare services. PMID:20027786

  13. Can red flowers be conspicuous to bees? Bombus dahlbomii and South American temperate forest flowers as a case in point.

    PubMed

    Martínez-Harms, J; Palacios, A G; Márquez, N; Estay, P; Arroyo, M T K; Mpodozis, J

    2010-02-15

    It has been argued that trichromatic bees with photoreceptor spectral sensitivity peaks in the ultraviolet (UV), blue and green areas of the spectrum are blind to long wavelengths (red to humans). South American temperate forests (SATF) contain a large number of human red-looking flowers that are reported to be visited by the bumblebee Bombus dahlbomii. In the present study, B. dahlbomii's spectral sensitivity was measured through electroretinogram (ERG) recordings. No extended sensitivity to long wavelengths was found in B. dahlbomii. The spectral reflectance curves from eight plant species with red flowers were measured. The color loci occupied by these flowers in the bee color space was evaluated using the receptor noise-limited model. Four of the plant species have pure red flowers with low levels of chromatic contrast but high levels of negative L-receptor contrast. Finally, training experiments were performed in order to assess the role of achromatic cues in the detection and discrimination of red targets by B. dahlbomii. The results of the training experiments suggest that the bumblebee relies on achromatic contrast provided by the L-receptor to detect and discriminate red targets. These findings are discussed in the context of the evolutionary background under which the relationship between SATF species and their flower visitors may have evolved. PMID:20118307

  14. State of the Art in the Studies on Crotamine, a Cell Penetrating Peptide from South American Rattlesnake

    PubMed Central

    Kerkis, Irina; Hayashi, Mirian A. F.; Prieto da Silva, Alvaro R. B.; Pereira, Alexandre; De Sá Júnior, Paulo Luiz; Zaharenko, Andre J.; Rádis-Baptista, Gandhi; Kerkis, Alexandre; Yamane, Tetsuo

    2014-01-01

    Animal venoms comprise a naturally selected cocktail of bioactive peptides/proteins and other molecules, each of which playing a defined role thanks to the highly specific interactions with diverse molecular targets found in the prey. Research focused on isolation, structural, and functional characterizations of novel natural biologics (bioactive peptides/proteins from natural sources) has a long way to go through from the basic science to clinical applications. Herein, we overview the structural and functional characteristics of the myoneurotoxin crotamine, firstly isolated from the South American rattlesnake venom. Crotamine is the first venom peptide classified as a natural cell penetrating and antimicrobial peptide (CPP and AMP) with a more pronounced antifungal activity. In contrast to other known natural CPPs and AMPs, crotamine demonstrates a wide spectrum of biological activities with potential biotechnological and therapeutic values. More recent studies have demonstrated the selective in vitro anticancer activity of crotamine. In vivo, using a murine melanoma model, it was shown that crotamine delays tumor implantation, inhibits tumor cells proliferation, and also increases the survival of mice engrafted with subcutaneous melanoma. The structural and functional properties and also the possible biotechnological applications of minimized molecules derived from crotamine are also discussed. PMID:24551848

  15. Molecular assessment of the phylogeny and biogeography of a recently diversified endemic group of South American canids (Mammalia: Carnivora: Canidae).

    PubMed

    Tchaicka, Ligia; Freitas, Thales Renato Ochotorena de; Bager, Alex; Vidal, Stela Luengos; Lucherini, Mauro; Iriarte, Agustín; Novaro, Andres; Geffen, Eli; Garcez, Fabricio Silva; Johnson, Warren E; Wayne, Robert K; Eizirik, Eduardo

    2016-01-01

    To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus. PMID:27560989

  16. Munroa argentina, a Grass of the South American Transition Zone, Survived the Andean Uplift, Aridification and Glaciations of the Quaternary

    PubMed Central

    Amarilla, Leonardo D.; Anton, Ana M.; Chiapella, Jorge O.; Manifesto, María M.; Angulo, Diego F.; Sosa, Victoria

    2015-01-01

    The South American Transition Zone (SATZ) is a biogeographic area in which not only orogeny (Andes uplift) and climate events (aridification) since the mid-Miocene, but also Quaternary glaciation cycles had an important impact on the evolutionary history of the local flora. To study this effect, we selected Munroa argentina, an annual grass distributed in the biogeographic provinces of Puna, Prepuna and Monte. We collected 152 individuals from 20 localities throughout the species’ range, ran genetic and demographic analyses, and applied ecological niche modeling. Phylogenetic and population genetic analyses based on cpDNA and AFLP data identified three phylogroups that correspond to the previously identified subregions within the SATZ. Molecular dating suggests that M. argentina has inhabited the SATZ since approximately 3.4 (4.2–1.2) Ma and paleomodels predict suitable climate in these areas during the Interglacial period and the Last Glacial Maximum. We conclude that the current distribution of M. argentina resulted from the fragmentation of its once continuous range and that climate oscillations promoted ecological differences that favored isolation by creating habitat discontinuity. PMID:26110533

  17. Molecular assessment of the phylogeny and biogeography of a recently diversified endemic group of South American canids (Mammalia: Carnivora: Canidae).

    PubMed

    Tchaicka, Ligia; Freitas, Thales Renato Ochotorena de; Bager, Alex; Vidal, Stela Luengos; Lucherini, Mauro; Iriarte, Agustín; Novaro, Andres; Geffen, Eli; Garcez, Fabricio Silva; Johnson, Warren E; Wayne, Robert K; Eizirik, Eduardo

    2016-07-25

    To investigate the evolution and biogeography of an endemic group of South American foxes, we examined mitochondrial DNA control region sequences for 118 individuals belonging to all six extant species of the genus Lycalopex. Phylogenetic and molecular dating analyses supported the inference that this genus has undergone a very recent and rapid radiation, stemming from a common ancestor that lived ca. 1 million years ago. The Brazilian endemic L. vetulus was supported as the most basal species in this genus, whereas the most internal group is comprised by the recently diverged (ca. 350,000 years ago) Andean/Patagonian species L. griseus and L. culpaeus. We discuss the inferred phylogenetic relationships and divergence times in the context of the current geographic distributions of these species, and the likely effects of Pleistocene climatic changes on the biogeography of this group. Furthermore, a remarkable finding was the identification of multiple individuals classified as L. gymnocercus bearing mtDNA haplotypes clearly belonging to L. griseus, sampled in regions where the latter is not known to occur. At a minimum, this result implies the need to clarify the present-day geographic distribution of each of these fox species, while it may also indicate an ongoing hybridization process between them. Future testing of this hypothesis with in-depth analyses of these populations is thus a priority for understanding the history, evolutionary dynamics and present-day composition of this endemic Neotropical genus. PMID:27459260

  18. The first report of otarine herpesvirus-1-associated urogenital carcinoma in a South American fur seal (Arctocephalus australis).

    PubMed

    Dagleish, M P; Barrows, M; Maley, M; Killick, R; Finlayson, J; Goodchild, R; Valentine, A; Saunders, R; Willoughby, K; Smith, K C; Stidworthy, M F

    2013-07-01

    Otarine herpesvirus (OtHV)-1-associated urogenital carcinoma has been well documented in the California sea lion (Zalophus californianus, CSL), but this is the first report of this tumour in a captive South American fur seal (Arctocephalus australis, SAFS). The gross and microscopical morphology of the tumour in the SAFS was identical to that described previously in CSLs and the tumour in the present case had metastasized within the urogenital tract and draining lymph nodes and to the lungs and one kidney. Immunohistochemistry revealed intra- and extracytoplasmic labelling of herpesvirus antigen in the cells of the tumour tissue and transitional epithelium of the urethra. OtHV-1 nucleic acids were detected within tumour tissue and from a urogenital swab by polymerase chain reaction. The ranges of these two species of pinniped do not overlap normally in the wild, suggesting that transmission of OtHV-1 probably occurred in captivity. This confirmed susceptibility of the SAFS to the development of OtHV-1-associated urogenital carcinoma suggests that all species of Otariidae should be screened for OtHV-1 infection prior to movement within and between zoological collections. PMID:23218410

  19. Climate change and the distribution and conservation of the world's highest elevation woodlands in the South American Altiplano

    NASA Astrophysics Data System (ADS)

    Cuyckens, G. A. E.; Christie, D. A.; Domic, A. I.; Malizia, L. R.; Renison, D.

    2016-02-01

    Climate change is becoming an increasing threat to biodiversity. Consequently, methods for delineation, establishment and management of protected areas must consider the species' future distribution in response to future climate conditions. Biodiversity in high altitude semiarid regions may be particularly threatened by future climate change. In this study we assess the main environmental variables that best explain present day presence of the world's highest elevation woodlands in the South American Altiplano, and model how climate change may affect the future distribution of this unique ecosystem under different climate change scenarios. These woodlands are dominated by Polylepis tarapacana (Rosaceae), a species that forms unique biological communities with important conservation value. Our results indicate that five environmental variables are responsible for 91% and 90.3% of the present and future P. tarapacana distribution models respectively, and suggest that at the end of the 21st century, there will be a significant reduction (56%) in the potential habitat for this species due to more arid conditions. Since it is predicted that P. tarapacana's potential distribution will be severely reduced in the future, we propose a new network of national protected areas across this species distribution range in order to insure the future conservation of this unique ecosystem. Based on an extensive literature review we identify research topics and recommendations for on-ground conservation and management of P. tarapacana woodlands.

  20. Detection of calcium-binding proteins in venom and Duvernoy's glands of South American snakes and their secretions.

    PubMed

    Gonçalves, L R; Yamanouye, N; Nuñez-Burgos, G B; Furtado, M F; Britto, L R; Nicolau, J

    1997-10-01

    Calcium-binding proteins (CaBPs) have been described as involved in the stimulus-secretion coupling mechanisms in secretory glands. CaBPs were revealed with 45Ca, after electrophoresis in SDS-PAGE and transference to Zeta probe membranes, in Duvernoy's or venom gland homogenates from three families of South American snakes: Viperidae (Bothrops jararaca and Crotalus durissus terrificus); Elapidae (Micrurus corallinus), and Colubridae (Phylodrias patagoniensis and Oxyrhopus trigeminus). A band with an estimated molecular weight of 12 KDa was found in all glands studied. Bands with 17, 28, and 67 KDa were found in all glands, except in O. trigeminus Duvernoy's gland. A 18 KDa band was found in Viperidae and Elapidae venom glands, and a 88 KDa band was observed only in Viperidae venom gland homogenates. Some of these CaBPs were identified by Western blotting or by immunohistochemistry, as parvalbumin (12 KDa) and calbindin (28 KDa). When the secretion of these glands were analyzed, CaBPs were detected only in B. jararaca venom, with bands of 14, 35, 42, and 72 KDa. The profile of CaBPs was not modified at different phases of the secretory cycle of the glands, as well as after isoproterenol treatment. PMID:9440247

  1. A tropical speleothem record of glacial inception, the South American Summer Monsoon from 125 to 115 ka

    NASA Astrophysics Data System (ADS)

    Burns, S. J.; Kanner, L. C.; Cheng, H.; Edwards, R. Lawrence

    2015-06-01

    Relatively few marine or terrestrial paleoclimate studies have focused on glacial inception, the transition from an interglacial to a glacial climate state. As a result, neither the timing and structure of glacial inception nor the spatial pattern of glacial inception in different parts of the world is well known. Here we present results of a study of a speleothem from the Peruvian Andes that records changes in the intensity of South American Summer Monsoon (SASM) rainfall over the period from 125 to 115 ka. The results show that late in the last interglacial period, at 123 ka, SASM rainfall decreased, perhaps in response to a decrease in temperature and ice cover in the high northern latitudes and associated changes in atmospheric circulation. Then at 120.8 ka, a rapid increase in SASM rainfall marks the end of the last interglacial. After a more gradual increase between 120 and 117 ka, a second abrupt increase occurs at 117 ka. This pattern of change is mirrored to a remarkable degree by changes in the East Asian Monsoon. It is interpreted to reflect both a long-term gradual response of the monsoons to orbitally driven insolation changes and to rapid changes in Northern Hemisphere ice volume and temperature. Both monsoon systems are close to their full glacial conditions by 117 ka, before any significant decrease in atmospheric CO2.

  2. A Spectrophotometric Study of Plumage Color in the Eared Dove (Zenaida auriculata), the Most Abundant South American Columbiforme

    PubMed Central

    Benitez-Vieyra, Santiago Miguel

    2016-01-01

    For birds, plumage color perception is critical in social interactions such as courtship, in both monochromatic and dichromatic species. In the Eared Dove (Zenaida auriculata), perhaps the most abundant South American Columbiforme, the plumage of males and females looks alike and both sexes share the same melanistic coloration with gray and pink tones. The aim of this study was therefore to determine whether evident sexual dichromatism exists in the plumage of the Eared Dove using a spectrophotometry technique in the avian-visible range (300–700 nm). The results of the classic colorimetric variables analysis (hue, chroma and brightness) show that males are in general brighter and have higher UV chroma values than females. The avian visual model points to differences in achromatic and chromatic levels between males and females in body regions possibly involved in sexual selection (e.g. the crown). The model also indicates chromatic or achromatic differences in body regions not subject to sexual selection such as the black spots on the wing coverts and white tail bands, both of which may be involved in intra- or inter-gender-specific communication. PMID:27213273

  3. First occurrence of Beroe forskalii (Ctenophora) in South American Atlantic coastal waters, with notes on the use of macrociliary patterns for beroid identification.

    PubMed

    Oliveira, Otto M P; Migotto, Alvaro E

    2014-01-01

    Beroe forskalii Milne Edwards, 1841 is an oceanic ctenophore with a global distribution. The present study provides the first record of Beroe forskalii for the South American Atlantic coast, including a redescription of the species and a discussion on the utility of macrociliary patterns for the correct identification of at least some beroid species, exemplified by a comparison of the macrociliary patterns of Beroe forskalii and Beroe ovata (Chamisso & Eysenhardt, 1821). PMID:24871741

  4. Genetics, Gene Flow, and Glaciation: The Case of the South American Limpet Nacella mytilina.

    PubMed

    González-Wevar, Claudio A; Rosenfeld, Sebastián; Segovia, Nicolás I; Hüne, Mathias; Gérard, Karin; Ojeda, Jaime; Mansilla, Andrés; Brickle, Paul; Díaz, Angie; Poulin, Elie

    2016-01-01

    Glacial episodes of the Quaternary, and particularly the Last Glacial Maximum (LGM) drastically altered the distribution of the Southern-Hemisphere biota, principally at higher latitudes. The irregular coastline of Patagonia expanding for more than 84.000 km constitutes a remarkable area to evaluate the effect of Quaternary landscape and seascape shifts over the demography of near-shore marine benthic organisms. Few studies describing the biogeographic responses of marine species to the LGM have been conducted in Patagonia, but existing data from coastal marine species have demonstrated marked genetic signatures of post-LGM recolonization and expansion. The kelp-dweller limpet Nacella mytilina is broadly distributed along the southern tip of South America and at the Falkland/Malvinas Islands. Considering its distribution, abundance, and narrow bathymetry, N. mytilina represents an appropriate model to infer how historical and contemporary processes affected the distribution of intraspecific genetic diversity and structure along the southern tip of South America. At the same time, it will be possible to determine how life history traits and the ecology of the species are responsible for the current pattern of gene flow and connectivity across the study area. We conducted phylogeographic and demographic inference analyses in N. mytilina from 12 localities along Pacific Patagonia (PP) and one population from the Falkland/Malvinas Islands (FI). Analyses of the mitochondrial gene COI in 300 individuals of N. mytilina revealed low levels of genetic polymorphism and the absence of genetic differentiation along PP. In contrast, FI showed a strong and significant differentiation from Pacific Patagonian populations. Higher levels of genetic diversity were also recorded in the FI population, together with a more expanded genealogy supporting the hypothesis of glacial persistence of the species in these islands. Haplotype genealogy, and mismatch analyses in the FI population

  5. Moist Teleconnection Mechanisms for the Tropical South American and Atlantic Sector*.

    NASA Astrophysics Data System (ADS)

    Neelin, J. David; Su, Hui

    2005-09-01

    Teleconnections have traditionally been studied for the case of dry dynamical response to a given diabatic heat source. Important anomalies often occur within convective zones, for instance, in the observed remote response to El Niño. The reduction of rainfall and teleconnection propagation in deep convective regions poses theoretical challenges because feedbacks involving convective heating and cloud radiative effects come into play. Land surface feedbacks, including variations of land surface temperature, and ocean surface layer temperature response must be taken into account. During El Niño, descent and negative precipitation anomalies often extend across equatorial South America and the Atlantic intertropical convergence zone. Analysis of simulated mechanisms in a case study of the 1997/98 El Niño is used to illustrate the general principals of teleconnections occurring in deep convective zones, contrasting land and ocean regions. Comparison to other simulated events shows similar behavior. Tropospheric temperature and wind anomalies are spread eastward by wave dynamics modified by interaction with the moist convection zones. The traditional picture would have gradual descent balanced by radiative damping, but this scenario misses the most important balances in the moist static energy (MSE) budget. A small “zoo” of mechanisms is active in producing strong regional descent anomalies and associated drought. Factors common to several mechanisms include the role of convective quasi equilibrium (QE) in linking low-level moisture anomalies to free tropospheric temperature anomalies in a two-way interaction referred to as QE mediation. Convective heating feedbacks change the net static stability to a gross moist stability (GMS) M. The large cloud radiative feedback terms may be manipulated to appear as a modified static stability Meff, under approximations that are quantified for the quasi-equilibrium tropical circulation model used here. The relevant measure

  6. Moist Teleconnection Mechanisms for the Tropical South American and Atlantic Sector*.

    NASA Astrophysics Data System (ADS)

    Neelin, J. David; Su, Hui

    2005-09-01

    Teleconnections have traditionally been studied for the case of dry dynamical response to a given diabatic heat source. Important anomalies often occur within convective zones, for instance, in the observed remote response to El Niño. The reduction of rainfall and teleconnection propagation in deep convective regions poses theoretical challenges because feedbacks involving convective heating and cloud radiative effects come into play. Land surface feedbacks, including variations of land surface temperature, and ocean surface layer temperature response must be taken into account. During El Niño, descent and negative precipitation anomalies often extend across equatorial South America and the Atlantic intertropical convergence zone. Analysis of simulated mechanisms in a case study of the 1997/98 El Niño is used to illustrate the general principals of teleconnections occurring in deep convective zones, contrasting land and ocean regions. Comparison to other simulated events shows similar behavior. Tropospheric temperature and wind anomalies are spread eastward by wave dynamics modified by interaction with the moist convection zones. The traditional picture would have gradual descent balanced by radiative damping, but this scenario misses the most important balances in the moist static energy (MSE) budget. A small “zoo” of mechanisms is active in producing strong regional descent anomalies and associated drought. Factors common to several mechanisms include the role of convective quasi equilibrium (QE) in linking low-level moisture anomalies to free tropospheric temperature anomalies in a two-way interaction referred to as QE mediation. Convective heating feedbacks change the net static stability to a gross moist stability (GMS) M. The large cloud radiative feedback terms may be manipulated to appear as a modified static stability Meff, under approximations that are quantified for the quasi-equilibrium tropical circulation model used here. The relevant measure

  7. Molecular Epidemiology of Vancomycin-Resistant Enterococcus faecium: a Prospective, Multicenter Study in South American Hospitals▿

    PubMed Central

    Panesso, Diana; Reyes, Jinnethe; Rincón, Sandra; Díaz, Lorena; Galloway-Peña, Jessica; Zurita, Jeannete; Carrillo, Carlos; Merentes, Altagracia; Guzmán, Manuel; Adachi, Javier A.; Murray, Barbara E.; Arias, Cesar A.

    2010-01-01

    Enterococcus faecium has emerged as an important nosocomial pathogen worldwide, and this trend has been associated with the dissemination of a genetic lineage designated clonal cluster 17 (CC17). Enterococcal isolates were collected prospectively (2006 to 2008) from 32 hospitals in Colombia, Ecuador, Perú, and Venezuela and subjected to antimicrobial susceptibility testing. Genotyping was performed with all vancomycin-resistant E. faecium (VREfm) isolates by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing. All VREfm isolates were evaluated for the presence of 16 putative virulence genes (14 fms genes, the esp gene of E. faecium [espEfm], and the hyl gene of E. faecium [hylEfm]) and plasmids carrying the fms20-fms21 (pilA), hylEfm, and vanA genes. Of 723 enterococcal isolates recovered, E. faecalis was the most common (78%). Vancomycin resistance was detected in 6% of the isolates (74% of which were E. faecium). Eleven distinct PFGE types were found among the VREfm isolates, with most belonging to sequence types 412 and 18. The ebpAEfm-ebpBEfm-ebpCEfm (pilB) and fms11-fms19-fms16 clusters were detected in all VREfm isolates from the region, whereas espEfm and hylEfm were detected in 69% and 23% of the isolates, respectively. The fms20-fms21 (pilA) cluster, which encodes a putative pilus-like protein, was found on plasmids from almost all VREfm isolates and was sometimes found to coexist with hylEfm and the vanA gene cluster. The population genetics of VREfm in South America appear to resemble those of such strains in the United States in the early years of the CC17 epidemic. The overwhelming presence of plasmids encoding putative virulence factors and vanA genes suggests that E. faecium from the CC17 genogroup may disseminate in the region in the coming years. PMID:20220167

  8. Genetic characterization of Toxoplasma gondii isolates in dogs from Vietnam suggests their South American origin.

    PubMed

    Dubey, J P; Huong, Lam Thi Thu; Sundar, N; Su, C

    2007-05-31

    Dogs are considered a potential risk for transmission of Toxoplasma gondii to humans because they can mechanically transmit oocysts to people and in certain parts of the world dog meat is consumed by humans. The prevalence of T. gondii in 42 dogs from rural Vietnam was determined. Antibodies to T. gondii were assayed by the modified agglutination test, and found in 21 (50%) of 42 dogs with titers of 1:20 in six, 1:40 in seven, 1:80 in two, 1:160 in two, 1:320 in two, 1:640 in one, and 1:1280 or higher in one. Hearts, tongues and brains of 21 seropositive dogs were bioassayed in cats, mice or both. Tissues from eight seropositive dogs were fed to eight T. gondii-free cats. Feces of cats were examined for oocysts. T. gondii was isolated from eight dogs by bioassay in cats. Genotyping of these eight T. gondii isolates using polymorphisms at 10 nuclear markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and a new SAG2, and an apicoplast marker Apico revealed two genotypes. Both genotypes were previously identified from the dog isolates in Colombia, suggesting their South America origin. However, they are different from the predominant Type I, II and III lineages that are widely spread in North America and Europe. This is the first report of isolation of viable T. gondii from any host in Vietnam. PMID:17442492

  9. Maximal thermogenic capacity and non-shivering thermogenesis in the South American subterranean rodent Ctenomys talarum.

    PubMed

    Luna, Facundo; Roca, Pilar; Oliver, Jordi; Antenucci, C Daniel

    2012-10-01

    Subterranean rodents inhabit closed tunnel systems that are hypoxic and hypercapnic and buffer aboveground ambient temperature. In contrast to other strictly subterranean rodents, Ctenomys talarum exhibits activity on the surface during foraging and dispersion and hence, is exposed also to the aboveground environment. In this context, this species is a valuable model to explore how the interplay between underground and aboveground use affects the relationship among basal metabolic rate (BMR), cold-induced maximum metabolic rate (MMR), shivering (ST), and non-shivering thermogenesis (NST). In this work, we provide the first evidence of the presence of NST, including the expression of uncoupling proteins in brown adipose tissue (BAT), and shivering thermogenesis in Ctenomys talarum, a species belonging to the most numerous subterranean genus, endemic to South America. Our results show no differences in BMR, cold-induced MMR, and NST between cold- (15 °C) and warm- (25 °C) acclimated individuals. Furthermore, thermal acclimation had no effect on the expression of mitochondrial uncoupling protein 1 (UCP1) in BAT. Only cytochrome c oxidase (COX) content and activity increased during cold acclimation. When interscapular BAT was removed, NST decreased more than 30%, whereas cold-induced MMR remained unchanged. All together, these data suggest that cold-induced MMR reaches a maximum in warm-acclimated individuals and so a probable ceiling in NST and UCP1 expression in BAT. Possible thermogenic mechanisms explaining the increase in the oxidative capacity, mediated by COX in BAT of cold-acclimated individuals and the role of ST in subterranean life habits are proposed. PMID:22614630

  10. Digging Deeper: A Case Study of Farmer Conceptualization of Ecosystem Services in the American South

    NASA Astrophysics Data System (ADS)

    Quinn, Courtney E.; Quinn, John E.; Halfacre, Angela C.

    2015-10-01

    The interest in improved environmental sustainability of agriculture via biodiversity provides an opportunity for placed-based research on the conceptualization and articulation of ecosystem services. Yet, few studies have explored how farmers conceptualize the relationship between their farm and nature and by extension ecosystem services. Examining how farmers in the Southern Piedmont of South Carolina discuss and explain the role of nature on their farm, we create a detail-rich picture of how they perceive ecosystem services and their contributions to the agroeconomy. Using 34 semi-structured interviews, we developed a detail-rich qualitative portrait of these farmers' conceptualizations of ecosystem services. Farmers' conceptualization of four ecosystem services: provisioning, supporting, regulating, and cultural are discussed, as well as articulation of disservices. Results of interviews show that most interviewees expressed a basic understanding of the relationship between nature and agriculture and many articulated benefits provided by nature to their farm. Farmers referred indirectly to most services, though they did not attribute services to biodiversity or ecological function. While farmers have a general understanding and appreciation of nature, they lack knowledge on specific ways biodiversity benefits their farm. This lack of knowledge may ultimately limit farmer decision-making and land management to utilize ecosystem services for environmental and economic benefits. These results suggest that additional communication with farmers about ecosystem services is needed as our understanding of these benefits increases. This change may require collaboration between conservation biology professionals and extension and agriculture professionals to extended successful biomass provisioning services to other ecosystem services.

  11. Neuromuscular action of venom from the South American colubrid snake Philodryas patagoniensis.

    PubMed

    Carreiro da Costa, Roberta S; Prudêncio, Luiz; Ferrari, Erika Fonseca; Souza, Gustavo H M F; de Mello, Sueli Moreira; Prianti Júnior, Antonio Carlos Guimarães; Ribeiro, Wellington; Zamunér, Stella Regina; Hyslop, Stephen; Cogo, José Carlos

    2008-07-01

    Snakes of the opisthoglyphous genus Philodryas are widespread in South America and cause most bites by colubrids in this region. In this study, we examined the neurotoxic and myotoxic effects of venom from Philodryas patagoniensis in biventer cervicis and phrenic nerve-diaphragm preparations and we compared the biochemical activities of venoms from P. patagoniensis and Philodryas olfersii. Philodryas patagoniensis venom (40 microg/mL) had no effect on mouse phrenic nerve-diaphragm preparations but caused time-dependent neuromuscular blockade of chick biventer cervicis preparations. This blockade was not reversed by washing. The highest concentration of venom tested (40 microg/mL) significantly reduced (p<0.05) the contractures to exogenous acetylcholine (55 microM and 110 microM) and K(+) (13.4 mM) after 120 min; lower concentrations of venom had no consistent or significant effect on these responses. Venom caused a concentration- and time-dependent release of creatine kinase (CK) from biventer cervicis preparations. Histological analysis showed contracted muscle fibers at low venom concentrations and myonecrosis at high concentrations. Philodryas venoms had low esterase and phospholipase A(2) but high proteolytic activities compared to the pitviper Bothrops jararaca. SDS-PAGE showed that the Philodryas venoms had similar electrophoretic profiles, with most proteins having a molecular mass of 25-80 kDa. Both of the Philodryas venoms cross-reacted with bothropic antivenom in ELISA, indicating the presence of proteins immunologically related to Bothrops venoms. RP-HPLC of P. patagoniensis venom yielded four major peaks, each of which contained several proteins, as shown by SDS-PAGE. These results indicate that P. patagoniensis venom has neurotoxic and myotoxic components that may contribute to the effects of envenoming by this species. PMID:18455482

  12. Exploring the bacterial microbiota associated with native South American species of Aphis (Hemiptera: Aphididae).

    PubMed

    Arneodo, J D; Ortego, J

    2014-06-01

    Aphids harbor a variety of bacterial endosymbionts, including the obligate symbiont Buchnera aphidicola and diverse facultative symbionts. The former supplies its host with essential amino acids. The latter are not indispensable for insect survival, but often improve their host's fitness. To date, the study of such associations was restricted to aphids of Holarctic origin. The bacterial microbiota of seven Aphis species from Argentina was investigated. The presence of B. aphidicola was assessed by specific PCR. Additional symbionts were identified through PCR with eubacterial universal primers, cloning, and sequencing of nearly complete 16S rRNA gene, intergenic spacer region, and partial 23S rRNA gene and subjected to phylogenetic analysis. Infection with B. aphidicola was confirmed in every species analyzed. The facultative symbiont Serratia symbiotica was detected in Aphis malalhuina Mier Durante, Nieto Nafría & Ortego, 2003, Aphis senecionicoides Blanchard, 1944, and Aphis schinifoliae Blanchard, 1939, while Hamiltonella defensa was identified in Aphis mendocina Mier Durante, Ortego & Nieto Nafría, 2006. Arsenophonus sp. was found infecting Aphis melosae Mier Durante & Ortego, 1999, and a new, undescribed Aphis sp. In Aphis danielae Remaudière, 1994, no facultative symbionts could be recorded. When analyzing the highly conserved 16S rRNA gene, the phylogenetic tree grouped the S. symbiotica, H. defensa, and Arsenophonus isolates into three well-defined clusters showing little variability among clones corresponding to the same aphid host species. This article reports for the first time the endosymbionts associated with aphids native to South America. Despite their geographic origin, the qualitative composition of their microbiota revealed no evident differences from that described for aphids in the Northern Hemisphere. PMID:24736017

  13. Diversification and Species Boundaries of Rhinebothrium (Cestoda; Rhinebothriidea) in South American Freshwater Stingrays (Batoidea; Potamotrygonidae)

    PubMed Central

    Reyda, Florian B.; Marques, Fernando P. L.

    2011-01-01

    Background Neotropical freshwater stingrays (Batoidea: Potamotrygonidae) host a diverse parasite fauna, including cestodes. Both cestodes and their stingray hosts are marine-derived, but the taxonomy of this host/parasite system is poorly understood. Methodology Morphological and molecular (Cytochrome oxidase I) data were used to investigate diversity in freshwater lineages of the cestode genus Rhinebothrium Linton, 1890. Results were based on a phylogenetic hypothesis for 74 COI sequences and morphological analysis of over 400 specimens. Cestodes studied were obtained from 888 individual potamotrygonids, representing 14 recognized and 18 potentially undescribed species from most river systems of South America. Results Morphological species boundaries were based mainly on microthrix characters observed with scanning electron microscopy, and were supported by COI data. Four species were recognized, including two redescribed (Rhinebothrium copianullum and R. paratrygoni), and two newly described (R. brooksi n. sp. and R. fulbrighti n. sp.). Rhinebothrium paranaensis Menoret & Ivanov, 2009 is considered a junior synonym of R. paratrygoni because the morphological features of the two species overlap substantially. The diagnosis of Rhinebothrium Linton, 1890 is emended to accommodate the presence of marginal longitudinal septa observed in R. copianullum and R. brooksi n. sp. Patterns of host specificity and distribution ranged from use of few host species in few river basins, to use of as many as eight host species in multiple river basins. Significance The level of intra-specific morphological variation observed in features such as total length and number of proglottids is unparalleled among other elasmobranch cestodes. This is attributed to the large representation of host and biogeographical samples. It is unclear whether the intra-specific morphological variation observed is unique to this freshwater system. Nonetheless, caution is urged when using morphological

  14. Phylogeny of Amazona barbadensis and the Yellow-Headed Amazon Complex (Aves: Psittacidae): A New Look at South American Parrot Evolution

    PubMed Central

    Strzała, Tomasz

    2014-01-01

    The Yellow-shouldered Amazon (Amazona barbadensis) is the sole parrot of the genus Amazona that inhabits only dry forests. Its population has been dropping; therefore it has been the topic of many studies and conservation efforts. However, the phylogenetic relationship of this species to potential relatives classified within the Yellow-Headed Amazon (YHA) complex are still not clear. Therefore, we used more extensive data sets, including the newly sequenced mitochondrial genome of A. barbadensis, to conduct phylogenetic analyses. Various combinations of genes and many phylogenetic approaches showed that A. barbadensis clustered significantly with A. ochrocephala ochrocephala from Colombia and Venezuela, which created the Northern South American (NSA) lineage, clearly separated from two other lineages within the YHA complex, the Central (CA) and South American (SA). Tree topology tests and exclusion of rapidly evolving sites provided support for a NSA+SA grouping. We propose an evolutionary scenario for the YHA complex and its colonization of the American mainland. The NSA lineage likely represents the most ancestral lineage, which derived from Lesser Antillean Amazons and colonized the northern coast of Venezuela about a million years ago. Then, Central America was colonized through the Isthmus of Panama, which led to the emergence of the CA lineage. The southward expansion to South America and the origin of the SA lineage happened almost simultaneously. However, more intensive or prolonged gene flow or migrations have led to much weaker geographic differentiation of genetic markers in the SA than in the CA lineage. PMID:24823658

  15. Hematology, Serum Chemistry, and Early Hematologic Changes in Free-Ranging South American Fur Seals ( Arctocephalus australis ) at Guafo Island, Chilean Patagonia.

    PubMed

    Seguel, Mauricio; Muñoz, Francisco; Keenan, Alessandra; Perez-Venegas, Diego J; DeRango, Eugene; Paves, Hector; Gottdenker, Nicole; Müller, Ananda

    2016-07-01

    The establishment of clinical pathology baseline data is critical to evaluate temporal and spatial changes in marine mammal groups. Despite increased availability of studies on hematology and biochemistry of marine mammals, reference ranges are lacking for many populations, especially among fur seal species. During the austral summers of 2014 and 2015, we evaluated basic hematologic and biochemical parameters in clinically healthy, physically restrained South American fur seal ( Arctocephalus australis ) lactating females and 2-mo-old pups. We also assessed the temporal variation of hematology parameters on the pups during their first 2 mo of life. Reference ranges of lactating females were similar to those previously reported in other fur seal species. In the case of pups, reference ranges are similar to values previously reported in sea lion species. As expected, most biochemical and hematologic values differ significantly between adult females and pups. As in other otariids, South American fur seals pups are born with higher values of total red blood cells, hemoglobin, and packed cell volume, and lower numbers of total leukocytes, neutrophils, lymphocytes, and eosinophils. To the best of our knowledge, data on hematology reference values for South American fur seals has not been previously reported and is useful for continued health monitoring of this species, as well as for comparisons with other otariid groups. PMID:27243331

  16. Phylogeny of Amazona barbadensis and the Yellow-headed Amazon complex (Aves: Psittacidae): a new look at South American parrot evolution.

    PubMed

    Urantówka, Adam Dawid; Mackiewicz, Paweł; Strzała, Tomasz

    2014-01-01

    The Yellow-shouldered Amazon (Amazona barbadensis) is the sole parrot of the genus Amazona that inhabits only dry forests. Its population has been dropping; therefore it has been the topic of many studies and conservation efforts. However, the phylogenetic relationship of this species to potential relatives classified within the Yellow-Headed Amazon (YHA) complex are still not clear. Therefore, we used more extensive data sets, including the newly sequenced mitochondrial genome of A. barbadensis, to conduct phylogenetic analyses. Various combinations of genes and many phylogenetic approaches showed that A. barbadensis clustered significantly with A. ochrocephala ochrocephala from Colombia and Venezuela, which created the Northern South American (NSA) lineage, clearly separated from two other lineages within the YHA complex, the Central (CA) and South American (SA). Tree topology tests and exclusion of rapidly evolving sites provided support for a NSA+SA grouping. We propose an evolutionary scenario for the YHA complex and its colonization of the American mainland. The NSA lineage likely represents the most ancestral lineage, which derived from Lesser Antillean Amazons and colonized the northern coast of Venezuela about a million years ago. Then, Central America was colonized through the Isthmus of Panama, which led to the emergence of the CA lineage. The southward expansion to South America and the origin of the SA lineage happened almost simultaneously. However, more intensive or prolonged gene flow or migrations have led to much weaker geographic differentiation of genetic markers in the SA than in the CA lineage. PMID:24823658

  17. Research capacity building and collaboration between South African and American partners: the adaptation of an intervention model for HIV/AIDS prevention in corrections research.

    PubMed

    Reddy, Priscilla; Taylor, Sandra E; Sifunda, Sibusiso

    2002-10-01

    This article examines a partnership between researchers from the United States who are involved in corrections health issues and scientists from South Africa who conduct prison health research, a previously underresearched area in South Africa. The article discusses some of the challenges as well as opportunities for knowledge and skills exchange via capacity building and collaboration strategies. Through historical and contemporary perspectives, it also discusses barriers and benefits of collaboration when forging links between researchers from developed and less developed nations. A focus on conducting public health research in South Africa, and on HIV/AIDS studies in particular, is placed within the context of the 2001 document of the Council on Health Research for Development. The South African prison health study represents a collaborative between the South African National Health Promotion Research and Development Group of the Medical Research Council, the South African Department of Correctional Services, and Emory University in Atlanta, Georgia. The article illuminates the process of adapting a model for a postapartheid prison study from one designed for use in the American correctional system. PMID:12413197

  18. Main animal welfare problems in ruminant livestock during preslaughter operations: a South American view.

    PubMed

    Gallo, C B; Huertas, S M

    2016-02-01

    Animals destined for meat production are usually exposed to many stressful conditions during production and particularly during preslaughter operations. Handling animals on farm, loading into and unloading from vehicles, transportation, passing through livestock markets, fasting, lairage and stunning can all affect their welfare. How badly welfare can be affected will depend on both the intrinsic factors of the specific type of animal involved and the extrinsic factors of the environment where those animals live or are being handled, including the animal handlers. In South America (SA), it has been part of a strategy for improving animal welfare (AW) to address not only ethical aspects, but to emphasize the close relationship existing between handling ruminants preslaughter and the quantity and quality of the meat they produce. This has resulted not only in improvements in AW, but has also brought economic rewards to producers which in turn can lead to higher incomes for them and hence better human welfare. For producers with a high number of animals, considering AW during production and preslaughter operations can determine the possibility of exporting and/or getting better prices for their products. At smallfarmer level, particularly in some less developed countries, where human welfare is impaired, using this strategy together with education has also been relevant. It is important that education and training in AW are done not only considering global knowledge, but also including specific geographical and climatic characteristics of each country and the cultural, religious and socio-economical characteristics of its people; therefore, research within the context of each country or region becomes relevant. The aim of this review was to show the results of research dealing with AW of ruminant livestock in Chile and some other SA countries. Some of the main problems encountered are related to lack of proper infrastructure to handle animals; long distance transport

  19. Native American prehistory of the middle Savannah River Valley. A synthesis of archaeological investigations on the Savannah River Site, Aiken and Barnwell Counties, South Carolina

    SciTech Connect

    Sassaman, K.E.; Brooks, M.J.; Hanson, G.T.; Anderson, D.G.

    1990-12-31

    Archaeological investigations on the United States Department of Energy`s (DOE) Savannah River Site (SRS) in South Carolina span 17 years and continue today through a cooperative agreement between DOE and the South Carolina Institute of Archaeology and Anthropology (SCIAA), University of South Carolina. The Savannah River Archaeological Research Program (SRARP) of SCIAA has been and continues to be the sole archaeological consultant for DOE-SRS. This report documents technical aspects of all prehistoric archaeological research conducted by the SRARP between 1973 and 1987. Further, this report provides interpretative contexts for archaeological resources as a basis for an archaeological resource plan reported elsewhere (SRARP 1989), and as a comprehensive statement of our current understanding of Native American prehistory. 400 refs., 130 figs., 39 tabs.

  20. The idealized cultural identities model on help-seeking and child sexual abuse: a conceptual model for contextualizing perceptions and experiences of South Asian Americans.

    PubMed

    Kanukollu, Shanta N; Mahalingam, Ramaswami

    2011-03-01

    In this paper, we propose an interdisciplinary framework to study perceptions of child sexual abuse and help-seeking among South Asians living in the United States. We integrate research on social marginality, intersectionality, and cultural psychology to understand how marginalized social experience accentuates South Asian immigrants' desire to construct a positive self-identity. Using model minority ideology as an example of such a construction, we highlight its role in silencing the topic of child sexual abuse within this immigrant community as well as its impact on attitudes towards professional mental health services. We contend that our framework, the idealized cultural identities model on help-seeking and child sexual abuse, provides a unique analytical model for clinicians and researchers to understand how South Asian Americans process, experience, and react to child sexual abuse. PMID:21442534

  1. Paleoseismic and Geomorphic Evidence for Quaternary Fault Slip on the Central Range Fault, South American-Caribbean Plate Boundary, Trinidad

    NASA Astrophysics Data System (ADS)

    Prentice, C. S.; Weber, J.; Crosby, C. J.

    2001-12-01

    The island of Trinidad is located along the transform plate boundary between the South American and Caribbean plates. GPS measurements show that relative motion along this boundary is nearly E-W right-lateral shear (Weber et al., 2001). Analysis and comparison of historic triangulation and GPS data suggest that a significant fraction (14+/-3 mm/yr) of the total plate-boundary motion (about 20 mm/yr) is being accommodated across the Central Range Fault in central Trinidad. Our new paleoseismic studies demonstrate that Quaternary surface rupture has occurred on this previously unrecognized, historically aseismic, active fault. Geomorphic evidence of Quaternary faulting along the Central Range Fault includes linear drainages, aligned topographic saddles and troughs, offset ridges, right-laterally deflected streams, and linear scarps. We mapped these features using 1:20,000 scale aerial photographs and field reconnaissance along a 25-km-long section between Pointe-a-Pierre on the west coast and Navet Dam. Geomorphic features near Manzanilla Bay on the east coast suggest that the Central Range Fault continues across the island as a Quaternary feature for another 25 km to the northeast. Marine geophysical surveys suggest this fault continues offshore to the west (Warm Springs fault), and steps to the north across the Gulf of Paria pull-apart basin to the El Pilar Fault. The extent of the fault offshore to the east is unknown. We exposed a 6-m-wide shear zone within Pliocene(?) material in a trench cut into a fluvial terrace, south of Samlalsingh Road near Bonne Aventure. The overlying Quaternary fluvial gravel is faulted and folded across the shear zone, and Quaternary fluvial deposits are faulted against the shear zone on the north side. A second excavation across a prominent scarp near Tabaquite, 12 km northeast of Samlalsingh Road, exposed a colluvial wedge and overlying unfaulted sediments. We interpret the colluvial wedge to represent deposits shed off the scarp in

  2. Spatiotemporal variability of rainfall extremes in monsoonal climates - examples from the South American Monsoon and the Indian Monsoon Systems (Invited)

    NASA Astrophysics Data System (ADS)

    Bookhagen, B.; Boers, N.; Marwan, N.; Malik, N.; Kurths, J.

    2013-12-01

    Monsoonal rainfall is the crucial component for more than half of the world's population. Runoff associated with monsoon systems provide water resources for agriculture, hydropower, drinking-water generation, recreation, and social well-being and are thus a fundamental part of human society. However, monsoon systems are highly stochastic and show large variability on various timescales. Here, we use various rainfall datasets to characterize spatiotemporal rainfall patterns using traditional as well as new approaches emphasizing nonlinear spatial correlations from a complex networks perspective. Our analyses focus on the South American (SAMS) and Indian (ISM) Monsoon Systems on the basis of Tropical Rainfall Measurement Mission (TRMM) using precipitation radar and passive-microwave products with horizontal spatial resolutions of ~5x5 km^2 (products 2A25, 2B31) and 25x25 km^2 (3B42) and interpolated rainfall-gauge data for the ISM (APHRODITE, 25x25 km^2). The eastern slopes of the Andes of South America and the southern front of the Himalaya are characterized by significant orographic barriers that intersect with the moisture-bearing, monsoonal wind systems. We demonstrate that topography exerts a first-order control on peak rainfall amounts on annual timescales in both mountain belts. Flooding in the downstream regions is dominantly caused by heavy rainfall storms that propagate deep into the mountain range and reach regions that are arid and without vegetation cover promoting rapid runoff. These storms exert a significantly different spatial distribution than average-rainfall conditions and assessing their recurrence intervals and prediction is key in understanding flooding for these regions. An analysis of extreme-value distributions of our high-spatial resolution data reveal that semi-arid areas are characterized by low-frequency/high-magnitude events (i.e., are characterized by a ';heavy tail' distribution), whereas regions with high mean annual rainfall have a

  3. High Precision U/Pb Geochronology of Eocene-Miocene South American Land Mammal Ages at Gran Barranca, Argentina

    NASA Astrophysics Data System (ADS)

    Dunn, R. E.; Kohn, M. J.; Madden, R. H.; Strömberg, C. E.; Carlini, A. A.

    2009-12-01

    Constraining the ages and duration of Cenozoic South American Land Mammal Ages (SALMAs) has been based on 40Ar/39Ar dating and magnetic polarity stratigraphy. At Gran Barranca (68.7°W, 45.7°S) - South America’s most important site and sequence for constraining SALMAs -uncertainties of ~ 1 Myr persist. To better constrain the ages of mammalian and plant assemblages and stable isotope stratigraphies, we employed high-precision (±50 kyr) single-crystal zircon U/Pb dating. These results generally confirm previous chronologies, but change the timing or duration of some SALMAs at Gran Barranca by 0.5-1 Myr. We collected 23 tuffs from six members of the Sarmiento Formation that contain 7 successive formally recognized SALMAs spanning the middle Eocene through the early Miocene. These strata include the type faunas for the Barrancan, Mustersan and Colhuehuapian SALMAs. Zircons were separated and chemically treated using standard techniques, spiked with EARTHTIME ET535, and analyzed for U-Pb ratios at Boise State University. Simpson’s Y, a prominent marker tuff within the Barrancan SALMA, yielded a date of ˜40.0 Ma. The Rosado Tuff, in the Rosado Member, contains Mustersan SALMA age mammals and yields a date of ˜38.3 Ma. Two tuffs in the Lower Puesto Almendra Member (Bed 10 and the Kay Tuff, stratigraphically above a Mustersan SALMA mammal assemblage) yielded ages of ˜37.0 and ˜36.9 Ma respectively. The Big Mammal Tuff at the base of the Colhuehuapian SALMA is ˜20.9 Ma, and the MMZ24.5 Tuff between the Colhuehuapian and Pinturan SALMAs is ˜19.1 Ma. Together with published magnetostratigraphy, these U/Pb dates have the following implications: (a) The known duration of the Barrancan SALMA is shortened by ~ 1 Myr and spans 40.5-39.0 Ma, (b) The Mustersan SALMA at Gran Barranca is between ˜38.3 and ˜37.0 Ma, (c) The Colhuehuapian SALMA must fall between ˜20.9 and ˜19.8 Ma, and (d) the fossil levels referred to the Pinturan SALMA are bracketed between ˜19.1 and

  4. A review of the South American monsoon history as recorded in stable isotopic proxies over the past two millennia

    NASA Astrophysics Data System (ADS)

    Vuille, M.; Burns, S. J.; Taylor, B. L.; Cruz, F. W.; Bird, B. W.; Abbott, M. B.; Kanner, L. C.; Cheng, H.; Novello, V. F.

    2012-08-01

    We review the history of the South American summer monsoon (SASM) over the past ~2000 yr based on high-resolution stable isotope proxies from speleothems, ice cores and lake sediments. Our review is complemented by an analysis of an isotope-enabled atmospheric general circulation model (GCM) for the past 130 yr. Proxy records from the monsoon belt in the tropical Andes and SE Brazil show a very coherent behavior over the past 2 millennia with significant decadal to multidecadal variability superimposed on large excursions during three key periods: the Medieval Climate Anomaly (MCA), the Little Ice Age (LIA) and the current warm period (CWP). We interpret these three periods as times when the SASM's mean state was significantly weakened (MCA and CWP) and strengthened (LIA), respectively. During the LIA each of the proxy archives considered contains the most negative δ18O values recorded during the entire record length. On the other hand, the monsoon strength is currently rather weak in a 2000-yr historical perspective, rivaled only by the low intensity during the MCA. Our climatic interpretation of these archives is consistent with our isotope-based GCM analysis, which suggests that these sites are sensitive recorders of large-scale monsoon variations. We hypothesize that these centennial-scale climate anomalies were at least partially driven by temperature changes in the Northern Hemisphere and in particular over the North Atlantic, leading to a latitudinal displacement of the ITCZ and a change in monsoon intensity (amount of rainfall upstream over the Amazon Basin). This interpretation is supported by several independent records from different proxy archives and modeling studies. Although ENSO is the main forcing for δ18O variability over tropical South America on interannual time scales, our results suggest that its influence may be significantly modulated by North Atlantic climate variability on longer time scales. Finally, our analyses indicate that isotopic

  5. A review of the South American Monsoon history as recorded in stable isotopic proxies over the past two millennia

    NASA Astrophysics Data System (ADS)

    Vuille, M.; Burns, S. J.; Taylor, B. L.; Cruz, F. W.; Bird, B. W.; Abbott, M. B.; Kanner, L. C.; Cheng, H.; Novello, V. F.

    2012-02-01

    We review the history of the South American summer monsoon (SASM) over the past ~2000 yr based on high-resolution stable isotope proxies from speleothems, ice cores and lake sediments. Our review is complemented by an analysis of an isotope-enabled atmospheric General Circulation Model (GCM) for the past 130 yr. Proxy records from the monsoon belt in the tropical Andes and SE Brazil show a very coherent behavior over the past 2 millennia with significant decadal to multidecadal variability superimposed on large excursions during three key periods, the Medieval Climate Anomaly (MCA), the Little Ice Age (LIA) and the Current Warm Period (CWP). We interpret these three periods as times when the SASM's mean state was significantly weakened (MCA and CWP) and strengthened (LIA), respectively. During the LIA each of the proxy archives considered contains the most negative δ18O values recorded during the entire record length. On the other hand the monsoon strength is currently rather weak in a 2000-yr historical perspective, rivaled only by the low intensity during the MCA. Our climatic interpretation of these archives is consistent with our isotope-based GCM analysis, which suggests that these sites are sensitive recorders of large-scale monsoon variations. We hypothesize that these centennial-scale climate anomalies were at least partially driven by temperature changes in the Northern Hemisphere and in particular over the North Atlantic, leading to a latitudinal displacement of the ITCZ and a change in monsoon intensity over the tropical continent. This interpretation is supported by several independent proxy archives and modeling studies. Although ENSO is the main forcing for δ18O variability over tropical South America on interannual time scales, our results suggest that its influence may be significantly modulated by North Atlantic climate variability on longer time scales. Finally our analyses indicate that isotopic proxies, because of their ability to integrate

  6. Ground based chemical characterization of submicron aerosol during the South American Biomass Burning Analysis (SAMBBA) field experiment

    NASA Astrophysics Data System (ADS)

    Brito, Joel; Artaxo, Paulo; Varanda Rizzo, Luciana; Johnson, Ben; Haywood, Jim; Longo, Karla; Freitas, Saulo; Coe, Hugh

    2013-04-01

    This work presents the results of an Aerosol Chemical Speciation Monitor (ACSM) which was successfully operated at a ground station in Porto Velho, Brazil, during the South American Biomass Burning Analysis (SAMBBA). SAMBBA is an international research project based on experimental and modeling activities designed to investigate the impacts of biomass burning emissions on climate, air quality and numerical weather prediction over South America. The measurement program was headed by the deployment of UK's Facility for Airborne Atmospheric Measurements (FAAM) BAe-146 research aircraft over Brazil during the dry season of 2012. The aircraft operation was coordinated with ground-based measurements at Porto Velho, operated by the University of Sao Paulo. Besides the aerosol chemical speciation, continuous measurements of aerosol size distribution and optical properties were carried out at the ground station, together with CO, CO2 and O3. Filters for trace elements measured by XRF and for OC/EC determined using a Sunset instrument were also collected at the ground based component of SAMBBA. The ACSM collected data for three weeks during September 2012. This period included a strong biomass burning event which showed a marked peak in f60, linked with Levoglucosan, a well-known biomass burning marker. During the biomass burning event, organics concentrations rose up to 80 μg/m3, black carbon close to 6 μg/m3 and CO mixing ratio above 2 ppmv. Fast biomass burning aerosol processing in the atmosphere could be observed through the relative contributions of C2H3O+ vs. CO2+ relative to total organic mass (f44 vs. f43). A clear diurnal variation throughout the sampling period has been observed for organic aerosols with a median peak of 9 μg/m3 at 04:00 LT and a minima of 5 μg/m3 at 18:00 LT. Preliminary results indicate that organics are responsible for 85% of PM1 non-refractory aerosols. The data set will allow the study of interactions between biomass burning and biogenic

  7. A Consensus-Based Interpretation of the Benchmark Evidence from South American Trials: Treatment of Intracranial Pressure Trial.

    PubMed

    Chesnut, Randall M; Bleck, Thomas P; Citerio, Giuseppe; Classen, Jan; Cooper, D James; Coplin, William M; Diringer, Michael N; Grände, Per-Olof; Hemphill, J Claude; Hutchinson, Peter J; Le Roux, Peter; Mayer, Stephan A; Menon, David K; Myburgh, John A; Okonkwo, David O; Robertson, Claudia S; Sahuquillo, Juan; Stocchetti, Nino; Sung, Gene; Temkin, Nancy; Vespa, Paul M; Videtta, Walter; Yonas, Howard

    2015-11-15

    Widely-varying published and presented analyses of the Benchmark Evidence From South American Trials: Treatment of Intracranial Pressure (BEST TRIP) randomized controlled trial of intracranial pressure (ICP) monitoring have suggested denying trial generalizability, questioning the need for ICP monitoring in severe traumatic brain injury (sTBI), re-assessing current clinical approaches to monitored ICP, and initiating a general ICP-monitoring moratorium. In response to this dissonance, 23 clinically-active, international opinion leaders in acute-care sTBI management met to draft a consensus statement to interpret this study. A Delphi method-based approach employed iterative pre-meeting polling to codify the group's general opinions, followed by an in-person meeting wherein individual statements were refined. Statements required an agreement threshold of more than 70% by blinded voting for approval. Seven precisely-worded statements resulted, with agreement levels of 83% to 100%. These statements, which should be read in toto to properly reflect the group's consensus positions, conclude that the BEST TRIP trial: 1) studied protocols, not ICP-monitoring per se; 2) applies only to those protocols and specific study groups and should not be generalized to other treatment approaches or patient groups; 3) strongly calls for further research on ICP interpretation and use; 4) should be applied cautiously to regions with much different treatment milieu; 5) did not investigate the utility of treating monitored ICP in the specific patient group with established intracranial hypertension; 6) should not change the practice of those currently monitoring ICP; and 7) provided a protocol, used in non-monitored study patients, that should be considered when treating without ICP monitoring. Consideration of these statements can clarify study interpretation. PMID:26061135

  8. Morphology, Chemistry and Function of the Postpharyngeal Gland in the South American Digger Wasps Trachypus boharti and Trachypus elongatus

    PubMed Central

    Herzner, Gudrun; Kaltenpoth, Martin; Poettinger, Theodor; Weiss, Katharina; Koedam, Dirk; Kroiss, Johannes; Strohm, Erhard

    2013-01-01

    Microbes pose severe threats to animals as competitors or pathogens and strongly affect the evolution of life history traits like parental care. Females of the European beewolf Philanthus triangulum, a solitary digger wasp, provision their offspring with paralyzed honeybees and embalm them with the secretion from large postpharyngeal glands (PPG) that contain mainly unsaturated hydrocarbons. This coating changes the physico-chemical properties of the prey surface, causes a reduction of water condensation and retards growth of mold fungi. Here we examined the closely related South American genus Trachypus, which shows a life-history similar to Philanthus. We investigated whether Trachypus spp. also possess PPGs and embalm larval provisions. Using histological methods and 3D reconstructions we show that Trachypus boharti and T. elongatus possess PPGs that are similar to P. triangulum but somewhat smaller. The ultrastructure of the gland epithelium suggests that the gland content is at least partly sequestered from the hemolymph. Chemical analyses using gas chromatography / mass spectrometry revealed that both the cuticle and PPGs of Trachypus contain mainly unsaturated long-chain hydrocarbons. The gland of T. boharti additionally contains long-chain ketones. The hydrocarbons from the PPG of T. elongatus occurred on prey bees excavated from nests in the field but not on conspecific control bees. While the embalming only slightly elevated the amount of hydrocarbons on prey bees, the proportion of unsaturated hydrocarbons, which is crucial for the antifungal effect, was significantly increased. The Trachypus species under study possess PPGs that are very similar to the PPG of P. triangulum with regard to morphology, ultrastructure and chemistry. Moreover, we provide clear evidence that T. elongatus females embalm their prey, presumably as a means of prey preservation. The observed differences among Trachypus and Philanthus in gland size and prey embalming may have

  9. Towards a revision of the South American genus Praocis Eschscholtz (Coleoptera, Tenebrionidae), with estimation of the diversity of each subgenus.

    PubMed

    Flores, Gustavo E; Pizarro-Araya, Jaime

    2014-01-01

    A review of the subgenera of the South American genus Praocis Eschscholtz (Pimeliinae: Praociini) is presented. Praocis comprises 77 species and 8 subspecies arranged in nine subgenera distributed in arid lands from Central Peru and Bolivia to the Southern part of Patagonia in Chile and Argentina. For each subgenus of Praocis: Praocis Eschscholtz, Mesopraocis Flores & Pizarro-Araya, subgen. n., Anthrasomus Guérin-Méneville, Filotarsus Gay & Solier, Postpraocis Flores & Pizarro-Araya, subgen. n., Hemipraocis Flores & Pizarro-Araya, subgen. n., Orthogonoderes Gay & Solier, Praonoda Flores & Pizarro-Araya, subgen. n., and Praocida Flores & Pizarro-Araya, subgen. n., we present a diagnosis using new and constant characters of adult morphology such as clypeal configuration, length and proportion of antennomeres 9, 10 and 11, arrangement of apical tomentose sensory patches on antennomeres 10 and 11, anterior margin of prosternum, lateral margin of elytron, ventral surface of profemora, and shape of protibiae. An identification key for the nine subgenera of Praocis is presented. Type species are designated for the five new subgenera; for Mesopraocis: Praocis calderana Kulzer, for Postpraocis: Praocis pentachorda Burmeister, for Hemipraocis: Praocis sellata Berg, for Praonoda: Praocis bicarinata Burmeister, for Praocida: Praocis zischkai Kulzer, and for the previously described subgenus Orthogonoderes: Praocis subreticulata Gay & Solier. The current number of species and the estimated number of species to be described are presented. The distribution ranges of the subgenera, including new records from collections and recent expeditions, are given. Habitat preferences and a discussion of the biogeography of the genus are also presented. PMID:25009424

  10. Sequence analysis of the 5′ third of glycoprotein C gene of South American bovine herpesviruses 1 and 5

    PubMed Central

    Traesel, C.K.; Bernardes, L.M.; Spilki, F.R.; Weiblen, R.; Flores, E.F.

    2015-01-01

    Bovine herpesviruses 1 (BoHV-1) and 5 (BoHV-5) share high genetic and antigenic similarities, but exhibit marked differences in tissue tropism and neurovirulence. The amino-terminal region of glycoprotein C (gC), which is markedly different in each of the viruses, is involved in virus binding to cellular receptors and in interactions with the immune system. This study investigated the genetic and antigenic differences of the 5′ region of the gC (5′ gC) gene (amino-terminal) of South American BoHV-1 (n=19) and BoHV-5 (n=25) isolates. Sequence alignments of 374 nucleotides (104 amino acids) revealed mean similarity levels of 97.3 and 94.2% among BoHV-1 gC (gC1), respectively, 96.8 and 95.6% among BoHV-5 gC (gC5), and 62 and 53.3% between gC1 and gC5. Differences included the absence of 40 amino acid residues (27 encompassing predicted linear epitopes) scattered throughout 5′ gC1 compared to 5′ gC5. Virus neutralizing assays testing BoHV-1 and BoHV-5 antisera against each isolate revealed a high degree of cross-neutralization between the viruses, yet some isolates were neutralized at very low titers by heterologous sera, and a few BoHV-5 isolates reacted weakly with either sera. The virus neutralization differences observed within the same viral species, and more pronounced between BoHV-1 and BoHV-5, likely reflect sequence differences in neutralizing epitopes. These results demonstrate that the 5′ gC region is well conserved within each viral species but is divergent between BoHV-1 and BoHV-5, likely contributing to their biological and antigenic differences. PMID:25760029

  11. A 2,300-year-long annually resolved record of the South American summer monsoon from the Peruvian Andes.

    PubMed

    Bird, Broxton W; Abbott, Mark B; Vuille, Mathias; Rodbell, Donald T; Stansell, Nathan D; Rosenmeier, Michael F

    2011-05-24

    Decadal and centennial mean state changes in South American summer monsoon (SASM) precipitation during the last 2,300 years are detailed using an annually resolved authigenic calcite record of precipitation δ(18)O from a varved lake in the Central Peruvian Andes. This unique sediment record shows that δ(18)O peaked during the Medieval Climate Anomaly (MCA) from A.D. 900 to 1100, providing evidence that the SASM weakened considerably during this period. Minimum δ(18)O values occurred during the Little Ice Age (LIA) between A.D. 1400 and 1820, reflecting a prolonged intensification of the SASM that was regionally synchronous. After the LIA, δ(18)O increased rapidly, particularly during the current warm period (CWP; A.D. 1900 to present), indicating a return to reduced SASM precipitation that was more abrupt and sustained than the onset of the MCA. Diminished SASM precipitation during the MCA and CWP tracks reconstructed Northern Hemisphere and North Atlantic warming and a northward displacement of the Intertropical Convergence Zone (ITCZ) over the Atlantic, and likely the Pacific. Intensified SASM precipitation during the LIA follows reconstructed Northern Hemisphere and North Atlantic cooling, El Niño-like warming in the Pacific, and a southward displacement of the ITCZ over both oceans. These results suggest that SASM mean state changes are sensitive to ITCZ variability as mediated by Western Hemisphere tropical sea surface temperatures, particularly in the Atlantic. Continued Northern Hemisphere and North Atlantic warming may therefore help perpetuate the recent reductions in SASM precipitation that characterize the last 100 years, which would negatively impact Andean water resources. PMID:21555548

  12. Towards a revision of the South American genus Praocis Eschscholtz (Coleoptera, Tenebrionidae), with estimation of the diversity of each subgenus

    PubMed Central

    Flores, Gustavo E.; Pizarro-Araya, Jaime

    2014-01-01

    Abstract A review of the subgenera of the South American genus Praocis Eschscholtz (Pimeliinae: Praociini) is presented. Praocis comprises 77 species and 8 subspecies arranged in nine subgenera distributed in arid lands from Central Peru and Bolivia to the Southern part of Patagonia in Chile and Argentina. For each subgenus of Praocis: Praocis Eschscholtz, Mesopraocis Flores & Pizarro-Araya, subgen. n., Anthrasomus Guérin-Méneville, Filotarsus Gay & Solier, Postpraocis Flores & Pizarro-Araya, subgen. n., Hemipraocis Flores & Pizarro-Araya, subgen. n., Orthogonoderes Gay & Solier, Praonoda Flores & Pizarro-Araya, subgen. n., and Praocida Flores & Pizarro-Araya, subgen. n., we present a diagnosis using new and constant characters of adult morphology such as clypeal configuration, length and proportion of antennomeres 9, 10 and 11, arrangement of apical tomentose sensory patches on antennomeres 10 and 11, anterior margin of prosternum, lateral margin of elytron, ventral surface of profemora, and shape of protibiae. An identification key for the nine subgenera of Praocis is presented. Type species are designated for the five new subgenera; for Mesopraocis: Praocis calderana Kulzer, for Postpraocis: Praocis pentachorda Burmeister, for Hemipraocis: Praocis sellata Berg, for Praonoda: Praocis bicarinata Burmeister, for Praocida: Praocis zischkai Kulzer, and for the previously described subgenus Orthogonoderes: Praocis subreticulata Gay & Solier. The current number of species and the estimated number of species to be described are presented. The distribution ranges of the subgenera, including new records from collections and recent expeditions, are given. Habitat preferences and a discussion of the biogeography of the genus are also presented. PMID:25009424

  13. Erasing the Past: A New Identity for the Damoclean Pathogen Causing South American Leaf Blight of Rubber

    PubMed Central

    da Hora Júnior, Braz Tavares; de Macedo, Davi Mesquita; Barreto, Robert Weingart; Evans, Harry C.; Mattos, Carlos Raimundo Reis; Maffia, Luiz Antonio; Mizubuti, Eduardo S. G.

    2014-01-01

    Background South American leaf blight (SALB) of rubber has been the main constraint to production in its neotropical centre of origin since commercial plantations were first established. The fungal causal agent was identified and described more than a century ago but its precise placement within the Ascomycota still remains uncertain. Indeed, such is the ambiguity surrounding the pathogen that each of the spore morphs would, according to their present classification, be placed in different ascomycete families: the Microcyclus sexual morph in the Planistromellaceae and the two purported asexual morphs - Fusicladium and Aposphaeria – in the Venturiaceae and Lophiostomataceae, respectively. Given the historical importance of the fungus and the ever-menacing threat that it poses to rubber production in the Palaeotropics – and, thus to the rubber industry and to the global economy – its phylogeny, as well as its biology, should be resolved as a matter of urgency. Methods and Results Here, six genomic regions (LSU rRNA, mtSSU, MCM7, EF-1α, Act and ITS) were used for reconstructing the molecular phylogeny of the SALB fungus based on material collected throughout Brazil. The analyses support the classification of the fungus in the family Mycosphaerellaceae s. str. (Capnodiales, Dothideomycetes) and place it firmly within the clade Pseudocercospora s. str., now accepted as one of the distinct genera within Mycosphaerellaceae. The new combination Pseudocercospora ulei is proposed and the life cycle of the fungus is confirmed, based on both experimental and phylogenetic evidence, with the Aposphaeria morph shown to have a spermatial rather than an infective-dispersal function. Conclusions Because the phylogeny of the SALB fungus has now been clarified, new insights of its epidemiology and genomics can be gained following comparison with closely-related, better-researched crop pathogens. PMID:25126853

  14. Evolution of naturally occurring 5'non-coding region variants of Hepatitis C virus in human populations of the South American region

    PubMed Central

    Moratorio, Gonzalo; Martínez, Mariela; Gutiérrez, María F; González, Katiuska; Colina, Rodney; López-Tort, Fernando; López, Lilia; Recarey, Ricardo; Schijman, Alejandro G; Moreno, María P; García-Aguirre, Laura; Manascero, Aura R; Cristina, Juan

    2007-01-01

    Background Hepatitis C virus (HCV) has been the subject of intense research and clinical investigation as its major role in human disease has emerged. Previous and recent studies have suggested a diversification of type 1 HCV in the South American region. The degree of genetic variation among HCV strains circulating in Bolivia and Colombia is currently unknown. In order to get insight into these matters, we performed a phylogenetic analysis of HCV 5' non-coding region (5'NCR) sequences from strains isolated in Bolivia, Colombia and Uruguay, as well as available comparable sequences of HCV strains isolated in South America. Methods Phylogenetic tree analysis was performed using the neighbor-joining method under a matrix of genetic distances established under the Kimura-two parameter model. Signature pattern analysis, which identifies particular sites in nucleic acid alignments of variable sequences that are distinctly representative relative to a background set, was performed using the method of Korber & Myers, as implemented in the VESPA program. Prediction of RNA secondary structures was done by the method of Zuker & Turner, as implemented in the mfold program. Results Phylogenetic tree analysis of HCV strains isolated in the South American region revealed the presence of a distinct genetic lineage inside genotype 1. Signature pattern analysis revealed that the presence of this lineage is consistent with the presence of a sequence signature in the 5'NCR of HCV strains isolated in South America. Comparisons of these results with the ones found for Europe or North America revealed that this sequence signature is characteristic of the South American region. Conclusion Phylogentic analysis revealed the presence of a sequence signature in the 5'NCR of type 1 HCV strains isolated in South America. This signature is frequent enough in type 1 HCV populations circulating South America to be detected in a phylogenetic tree analysis as a distinct type 1 sub-population. The

  15. A New Cryptic Species of South American Freshwater Pufferfish of the Genus Colomesus (Tetraodontidae), Based on Both Morphology and DNA Data

    PubMed Central

    Amaral, Cesar R. L.; Brito, Paulo M.; Silva, Dayse A.; Carvalho, Elizeu F.

    2013-01-01

    The Tetraodontidae are an Acantomorpha fish family with circumglobal distribution composed of 189 species grouped in 19 genera, occurring in seas, estuaries, and rivers between the tropical and temperate regions. Of these, the genus Colomesus is confined to South America, with what have been up to now considered only two species. C. asellus is spread over the entire Amazon, Tocantins-Araguaia drainages, and coastal environments from the Amazon mouth to Venezuela, and is the only freshwater puffers on that continent. C. psittacus is found in coastal marine and brackish water environments from Cuba to the northern coast of South America as far south as to Sergipe in Brazil. In the present contribution we used morphological data along with molecular systematics techniques to investigate the phylogeny and phylogeography of the freshwater pufferfishes of the genus Colomesus. The molecular part is based on a cytochrome C oxidase subunit I dataset constructed from both previously published and newly determined sequences, obtained from specimens collected from three distinct localities in South America. Our results from both molecular and morphological approaches enable us to identify and describe a new Colomesus species from the Tocantins River. We also discuss aspects of the historical biogeography and phylogeography of the South American freshwater pufferfishes, suggesting that it could be more recent than previously expected. PMID:24040239

  16. Active and Break periods in South American Monsoon System and their relation with wet and dry rainy season

    NASA Astrophysics Data System (ADS)

    Bilhalva da Silva, Aline; Alonso Gan, Manoel

    2015-04-01

    In the South American continent, as well as in Asia and Oceania, there are occurrence of break and active periods during the rainy season. The highlight characteristics of these periods relates to an amount of accumulated rainfall, in other words, the rainy season with more activity periods is related to higher accumulated rainfall, however within the break periods the amount of accumulated rainfall are below the average. To analyze these periods the precipitation data analysis with spatial resolution 1° latitude X 1° longitude, from Earth System Research Laboratory/National Oceanic and Atmospheric Administration (ESRL/NOAA) was used. Summers were selected (December to February) from 1989 to 2011 on the central region of South America (10°- 20°S and 50°- 60°W ) and an adaptation of monsoon rainfall index (MPI) was applied. The new criterion set up that cases will be classified as active (break) when the MPI is at least (most) half a standard deviation above (below) average climatological pentadal precipitation data, with persistence of this pattern for at least two consecutive pentads. The results showed that during the 22 analysed summers 31 active periods have occurred, with appreciable increasing trend in the number of cases per year, but maintaining the average duration around 4 pentads. Moreover, for the break periods 32 cases were identified, with no expressive increase or reduction tendency of the numbers of events, but with some tendency of shorter duration cases. It was also noted that from the 22 evaluated summers, 7 of them were anomalously wet, being the active period the mostlasting, and 11 summers anomalously dry, with the presence of higher duration break periods. In only 2 cases the total of the annual duration of break periods exceeded active periods, although the precipitation anomalies were positives, representing rainy years. Furthermore, 2 cases of active and break periods with the same duration during the year were observed, one of them

  17. The Maule, 2010, earthquake - geophysical and kinematic observations of the South American margin prior to the earthquake (Invited)

    NASA Astrophysics Data System (ADS)

    Oncken, O.; Haberland, C. A.; Moreno, M.; Melnick, D.; Tilmann, F.; Tipteq Research Groups

    2010-12-01

    distribution as evidenced by the recent Maule earthquake. Moreover, the latter coseismic rupture pattern was foreseeable from its pre-seismic locking pattern as derived by inversion of GPS observations during the previous decade. Neogene surface deformation at the Chilean coast related to these locking properties has been complex exhibiting tectonically uplifting areas along the coast driven by interseismically active reverse faulting. In addition, we observe coseismically subsiding domains along other parts of the coast - mostly above fully locked patches. Finally, we note that the characteristic peninsulas along the South American margin constitute stable rupture boundaries and appear to have done so for a protracted time as evidenced by their long-term uplift history since at least the Late Pliocene. This suggests barriers to rupture being related to anomalous properties of the plate interface affecting the mode of strain accumulation and plate interface rupture - like e.g. velocity strengthening in contrast to the weakening property of most of the remaining domains.

  18. Regional variability in diving physiology and behavior in a widely distributed air-breathing marine predator, the South American sea lion (Otaria byronia).

    PubMed

    Hückstädt, Luis A; Tift, Michael S; Riet-Sapriza, Federico; Franco-Trecu, Valentina; Baylis, Alastair M M; Orben, Rachael A; Arnould, John P Y; Sepulveda, Maritza; Santos-Carvallo, Macarena; Burns, Jennifer M; Costa, Daniel P

    2016-08-01

    Our understanding of how air-breathing marine predators cope with environmental variability is limited by our inadequate knowledge of their ecological and physiological parameters. Because of their wide distribution along both coasts of the sub-continent, South American sea lions (Otaria byronia) provide a valuable opportunity to study the behavioral and physiological plasticity of a marine predator in different environments. We measured the oxygen stores and diving behavior of South American sea lions throughout most of its range, allowing us to demonstrate that diving ability and behavior vary across its range. We found no significant differences in mass-specific blood volumes of sea lions among field sites and a negative relationship between mass-specific oxygen storage and size, which suggests that exposure to different habitats and geographical locations better explains oxygen storage capacities and diving capability in South American sea lions than body size alone. The largest animals in our study (individuals from Uruguay) were the shallowest and shortest duration divers, and had the lowest mass-specific total body oxygen stores, while the deepest and longest duration divers (individuals from southern Chile) had significantly larger mass-specific oxygen stores, despite being much smaller animals. Our study suggests that the physiology of air-breathing diving predators is not fixed, but that it can be adjusted, to a certain extent, depending on the ecological setting and or habitat. These adjustments can be thought of as a 'training effect': as the animal continues to push its physiological capacity through greater hypoxic exposure, its breath-holding capacity increases. PMID:27247316

  19. Culicoides vector species on three South American camelid farms seropositive for bluetongue virus serotype 8 in Germany 2008/2009.

    PubMed

    Schulz, Claudia; Ziller, Mario; Kampen, Helge; Gauly, Matthias; Beer, Martin; Grevelding, Christoph G; Hoffmann, Bernd; Bauer, Christian; Werner, Doreen

    2015-12-15

    Palearctic species of Culicoides (Diptera, Ceratopogonidae), in particular of the Obsoletus and Pulicaris complexes, were identified as putative vectors of bluetongue virus serotype 8 (BTV-8) on ruminant farms during the epizootic in Germany from 2006 to 2009. BTV may cause severe morbidity and mortality in ruminants and sporadically in South American camelids (SAC). However, the fauna of Culicoides spp. on SAC farms has not been investigated. Therefore, the ceratopogonid fauna was monitored on three farms with BTV-seropositive SAC in Germany. Black-light traps were set up on pastures and in stables from summer 2008 to autumn 2009. Additionally, ceratopogonids were caught in emergence traps mounted on llama dung and dung-free pasture from spring to autumn 2009. After morphological identification, selected Culicoides samples were analysed for BTV-RNA by real-time RT-PCR. The effects of the variables 'location', 'temperature' and 'humidity' on the number of Culicoides caught in black-light traps were modelled using multivariable Poisson regression. In total, 26 species of Culicoides and six other genera of biting midges were identified. The most abundant Culicoides spp. collected both outdoors and indoors with black-light traps belonged to the Obsoletus (77.4%) and Pulicaris (16.0%) complexes. The number of Culicoides peaked in summer, while no biting midges were caught during the winter months. Daily collections of Culicoides were mainly influenced by the location and depended on the interaction of temperature and humidity. In the emergence traps, species of the Obsoletus complex predominated the collections. In summary, the absence of BTV-RNA in any of the analysed Culicoides midges and in the BTV-seropositive SAC on the three farms together with the differences in the pathogenesis of BTV-8 in SAC compared to ruminants suggests a negligible role of SAC in the spread of the virus. Although SAC farms may provide similar suitable habitats for putative Culicoides

  20. Revised method to detect the onset and demise dates of the rainy season in the South American Monsoon areas

    NASA Astrophysics Data System (ADS)

    Garcia, Sâmia R.; Calheiros, Alan J. P.; Kayano, Mary T.

    2015-08-01

    This paper proposes the detection of dates for the onset and demise of the rainy season (ONR and DER, respectively) for some areas within the South American monsoon system (SAMS) region using procedures based on indices which could be easily calculated and subjected to very simple criterion. Previously, the time series of the averaged antisymmetric outgoing longwave radiation ([AOLR]) in each region of interest was used by some authors to detect ONR and DER. This method is referred to as OLD. First, it was proposed in this paper to smooth this time series with the five-pentad running mean ([RM_AOLR]). This modified method is called NEW. Then, an additional modification was adopted by smoothing the [AOLR] with the three-pentad running mean but with the [AOLR] in the most recent pentad being replaced by its climatological value ([RM_AOLRCLI]). This method is called NEW_CLI. For these methods, the criterion was that the first pentad with negative (positive) [AOLR] (or [RM_AOLR] or [RM_AOLRCLI]) is the ONR (DER) date in the region of interest. All these methods were applied for the Central Amazon (CAM) and Western-Central Brazil (WCB) regions during the rainy seasons in the 2001-2013 period. The efficiency of these methods was analyzed using the precipitation estimated from the Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis. The spatial average of the TRMM ([TRMM]) time series with threshold values, which depends on the area and season, was used to determine the ONR and DER dates. In this case, the single method based on the threshold value is called RAIN, and the method which considers the persistence of dry or wet condition is referred to as NEW_RAIN. Comparisons between the methods were performed by calculating the root mean square error (RMSE) when ONR and DER dates obtained from a given method were considered as the true dates. The advantages and disadvantages of the methods were discussed here. It was previously noted that the

  1. The mistress, the midwife, and the medical doctor: pregnancy and childbirth on the plantations of the antebellum American South, 1800-1860.

    PubMed

    Tunc, Tanfer Emin

    2010-01-01

    This article represents a step towards examining the relationship between three key figures in the antebellum American South: the plantation mistress, the slave-midwife, and the professional male physician. It elucidates how the experiences of pregnancy and childbirth, which brought women close to death, formed the basis of a deeper, positive relationship between the black and white women of the antebellum South, and assesses the ways in which the professionalization of medicine affected this reproductive bond. Evaluating such a complicated network of relationships necessitates dissecting numerous layers of social interaction, including black and white women's shared cultural experiences and solidarity as reproductive beings; the role, power, and significance of slave-midwives and other enslaved caretakers in white plantation births; the cooperation between pregnant bondswomen and plantation mistresses; and the impact that the burgeoning profession of medicine had on the procreative union between antebellum black and white women. PMID:20607898

  2. Evaluating effects of Everglades restoration on American crocodile populations in south Florida using a spatially-explicit, stage-based population model

    USGS Publications Warehouse

    Green, Timothy W.; Slone, Daniel H.; Swain, Eric D.; Cherkiss, Michael S.; Lohmann, Melinda; Mazzotti, Frank J.; Rice, Kenneth G.

    2014-01-01

    The distribution and abundance of the American crocodile (Crocodylus acutus) in the Florida Everglades is dependent on the timing, amount, and location of freshwater flow. One of the goals of the Comprehensive Everglades Restoration Plan (CERP) is to restore historic freshwater flows to American crocodile habitat throughout the Everglades. To predict the impacts on the crocodile population from planned restoration activities, we created a stage-based spatially explicit crocodile population model that incorporated regional hydrology models and American crocodile research and monitoring data. Growth and survival were influenced by salinity, water depth, and density-dependent interactions. A stage-structured spatial model was used with discrete spatial convolution to direct crocodiles toward attractive sources where conditions were favorable. The model predicted that CERP would have both positive and negative impacts on American crocodile growth, survival, and distribution. Overall, crocodile populations across south Florida were predicted to decrease approximately 3 % with the implementation of CERP compared to future conditions without restoration, but local increases up to 30 % occurred in the Joe Bay area near Taylor Slough, and local decreases up to 30 % occurred in the vicinity of Buttonwood Canal due to changes in salinity and freshwater flows.

  3. Trends in South American biomass burning detected with the GOES visible infrared spin scan radiometer atmospheric sounder from 1983 to 1991

    SciTech Connect

    Prins, E.M.; Menzel, W.P. |

    1994-08-01

    Previous work demonstrated the ability to manually detect subpixel fire activity in selected areas of the selva and cerrado regions in South America with shortwave and longwave infrared data available from the Geostationary Operational Environmental Satellite (GOES) visible infrared spin scan radiometer atmospheric sounder (VAS). This paper presents the GOES VAS automated biomass-burning algorithm (ABBA) which was developed to determine basin-wide trends in fire activity in South America utilizing the GOES VAS archive. Comparisons between the manual and automated techniques revealed that overall, the ABBA proved to be more consistent in identifying fires and better suited for trend analysis. The automated algorithm was applied daily to a study area extending from 5 deg S to 15 deg S and from 45 deg W to 70 deg W for 2 weeks at the peak of the burning seasons in South America in 1983, 1988, 1989, and 1991 in an effort to measure the areal extent of burning in South American during the past decade and to provide additional insight into the diurnal signature in satellite detection of biomass-burning activities. The expansion of the regions of burning are readily detected in a comparison of these 4 years. From 1983 to 1991 the amount of burning detected by the GOES VAS ABBA during these 2-week periods nearly doubled in the selva and mixed regions and tripled in the cerrado. Diurnal analyses confirmed earlier results indicating that the optimum time to monitor biomass burning is around 1530 UTC.

  4. Trends in South American biomass burning detected with the GOES visible infrared spin scan radiometer atmospheric sounder from 1983 to 1991

    NASA Technical Reports Server (NTRS)

    Prins, Elain M.; Menzel, W. Paul

    1994-01-01

    Previous work demonstrated the ability to manually detect subpixel fire activity in selected areas of the selva and cerrado regions in South America with shortwave and longwave infrared data available from the Geostationary Operational Environmental Satellite (GOES) visible infrared spin scan radiometer atmospheric sounder (VAS). This paper presents the GOES VAS automated biomass-burning algorithm (ABBA) which was developed to determine basin-wide trends in fire activity in South America utilizing the GOES VAS archive. Comparisons between the manual and automated techniques revealed that overall, the ABBA proved to be more consistent in identifying fires and better suited for trend analysis. The automated algorithm was applied daily to a study area extending from 5 deg S to 15 deg S and from 45 deg W to 70 deg W for 2 weeks at the peak of the burning seasons in South America in 1983, 1988, 1989, and 1991 in an effort to measure the areal extent of burning in South American during the past decade and to provide additional insight into the diurnal signature in satellite detection of biomass-burning activities. The expansion of the regions of burning are readily detected in a comparison of these 4 years. From 1983 to 1991 the amount of burning detected by the GOES VAS ABBA during these 2-week periods nearly doubled in the selva and mixed regions and tripled in the cerrado. Diurnal analyses confirmed earlier results indicating that the optimum time to monitor biomass burning is around 1530 UTC.

  5. Orbital and millennial-scale variability in the southernmost reaches of the South American summer monsoon during the last 50 ka BP

    NASA Astrophysics Data System (ADS)

    Chiessi, C. M.; Govin, A.; Mulitza, S.; Campos, M. D.

    2013-05-01

    The South American summer monsoon (SASM) and its related features (e.g., the South Atlantic Convergence Zone) deliver most of the precipitation for the Amazon and La Plata basins, the two largest drainage systems in South America. Marine, cave and lake records mainly from equatorial and tropical South America show that the strength of the SASM fluctuated on orbital and millennial time-scales, with a strong SASM during periods of high austral summer insolation. On millennial time-scales, precipitation in tropical South America to the south of the equator was increased during periods of a weak Atlantic meridional overturning circulation. Nevertheless, there is an almost complete lack of information about changes in precipitation in the subtropics and mid-latitudes of South America. This area comprises the transition from the southernmost reaches of the SASM to the semi-arid northern Patagonia, and is highly sensitive to changes in precipitation because: (i) it mainly receives precipitation during austral summer (related to the SASM); and (ii) it shows a steep gradient in total annual precipitation (going from ca. 1000 mm/yr around 30oS to ca. 200 mm/yr around 40oS). Here we present recently acquired data from the terrigenous fraction of marine sediment core GeoB6308-3 (39.30oS / 53.97oW / 3620 m water depth / 793 cm long) collected off southeastern South America. Our age model is based on 18 14C AMS ages while information about changes in continental climate comes from bulk sediment major element (i.e., Ca, Fe, Al, Si, Ti, K) proportions and Nd isotopes. The core recorded the last ca. 50 ka BP and its terrigenous sediment fraction shows a typical Central-West Argentinean / Patagonian isotopic signature. Through X-ray fluorescence scanning we were able to produce a record with mean temporal resolution of 35 yr. In our presentation, we will discuss changes in the southernmost reaches of the SASM and compare it to other records from South and Central America with the

  6. From South to North U.S.A.: The Afro-American Immigrant Experience in the Plays of August Wilson.

    ERIC Educational Resources Information Center

    Aronowitz, Beverly Lynne

    In contrast to the European immigration to the United States, the African immigrant encountered economic, psychological, and emotional disorientation to such an extent that these effects continue to influence and mold the lives of Afro-Americans. This document explores the Afro-American immigrant experience through a study of some of the plays…

  7. Early Holocene human remains from the Argentinean Pampas: additional evidence for distinctive cranial morphology of early South Americans.

    PubMed

    Pucciarelli, Héctor M; Perez, S Ivan; Politis, Gustavo G

    2010-10-01

    The cranial morphology of Early Holocene American human samples is characterized by a long and narrow cranial vault, whereas more recent samples exhibit a shorter and wider cranial vault. Two hypotheses have been proposed to account for the morphological differences between early and late-American samples: (a) the migratory hypothesis that suggests that the morphological variation between early and late American samples was the result of a variable number of migratory waves; and (b) the local diversification hypothesis, that is, the morphological differences between early and late American samples were mainly generated by local, random (genetic drift), and nonrandom factors (selection and phenotypic plasticity). We present the first craniometric study of three early skulls from the Argentinean Pampas, dated ∼8,000 cal. years BP (Arroyo Seco 2, Chocorí, and La Tigra), and one associated with mega-faunal remains (Fontezuelas skull). In addition, we studied several Late Holocene samples. We show that the skulls from the Argentinean Pampas are morphologically similar to other Early Holocene American skulls (i.e., Lagoa Santa from Brazil, Tequendama, Checua, and Aguazuque from Colombia, Lauricocha from Peru, and early Mexicans) that exhibit long and narrow cranial vaults. These samples differ from the Late Holocene American samples that exhibit a shorter and wider cranial vault. Our results underscore the important differences in cranial morphology between early and late-American samples. However, we emphasize the need for further studies to discuss alternative hypotheses regarding such differences. PMID:20623674

  8. Population Structure of mtDNA Variation due to Pleistocene Fluctuations in the South American Maned Wolf (Chrysocyon brachyurus, Illiger, 1815): Management Units for Conservation.

    PubMed

    González, Susana; Cosse, Mariana; Franco, María del Rosario; Emmons, Louise; Vynne, Carly; Duarte, José Maurício Barbanti; Beccacesi, Marcelo D; Maldonado, Jesús E

    2015-01-01

    The maned wolf (Chrysocyon brachyurus) is one of the largest South American canids, and conservation across this charismatic carnivore's large range is presently hampered by a lack of knowledge about possible natural subdivisions which could influence the population's viability. To elucidate the phylogeographic patterns and demographic history of the species, we used 2 mtDNA markers (D-loop and cytochrome b) from 87 individuals collected throughout their range, in Argentina, Bolivia, Brazil, and Uruguay. We found moderate levels of haplotype and nucleotide diversity, and the 14 D-loop haplotypes were closely related. Genetic structure results revealed 4 groups, and when coupled with model inferences from a coalescent analysis, suggested that maned wolves have undergone demographic fluctuations due to changes in climate and habitat during the Pleistocene glaciation period approximately 24000 years before present (YBP). This genetic signature points to an event that occurred within the timing estimated for the start of the contraction of the Cerrado around 50000 YBP. Our results reveal a genetic signature of population size expansion followed by contraction during Pleistocene interglaciations, which had similar impacts on other South American mammals. The 4 groups should for now be considered management units, within which future monitoring efforts should be conducted independently. PMID:26245781

  9. Where are the South American freshwater turtle blood flukes (Trematoda: Spirorchiidae)? The first morphological and molecular analysis of spirorchiid cercariae from freshwater snails in Brazil.

    PubMed

    Pinto, Hudson Alves; de Melo, Alan Lane; Brant, Sara Vanessa

    2015-12-01

    Trematodes belonging to the family Spirorchiidae are blood parasites mainly of turtles with a worldwide distribution. These flukes were recently reported in some marine turtles from South America, where the occurrence of spirorchiids in freshwater definitive and intermediate hosts is so far unknown. In the present study, three morphotypes of brevifurcate apharyngeate distome cercariae found in freshwater molluscs from an urban reservoir in Brazil were used for morphological and molecular (nuclear 28S rDNA) evaluation. Two morphotypes of cercariae, probably congeneric species, were found in 12/17,465 specimens of Biomphalaria spp. and differ from each other by body size and sequences (0.1%). They present morphology similar to North American freshwater spirorchiids (Spirorchis spp.), however surprisingly molecular data reveals that these lineages are more closely related to marine spirorchiids. A third species found in 2/777 Pomacea sp. differs morphologically from all previously described spirorchiid cercariae and genetically from spirorchiids with available sequences (16-19%), grouping in the phylogenetic tree with freshwater North American species. This is the first report of freshwater spirorchiids in South America and the first molecular confirmation of the involvement of a caenogastropod in the life cycle of spirorchiids. PMID:26253761

  10. Isolates of Sarcocystis falcatula-like organisms from South American opossums Didelphis marsupialis and Didelphis albiventris from São Paulo, Brazil.

    PubMed

    Dubey, J P; Lindsay, D S; Rosenthal, B M; Kerber, C E; Kasai, N; Pena, H F; Kwok, O C; Shen, S K; Gennari, S M

    2001-12-01

    Isolates of Sarcocystis falcatula-like organisms from South American opossums were characterized based on biological and morphological criteria. Sporocysts from intestinal scrapings of 1 Didelphis marsupialis and 8 Didelphis albiventris from São Paulo, Brazil, were fed to captive budgerigars (Melopsittacus undulatus). Budgerigars fed sporocysts from all 9 isolates became ill and S. falcatula-like schizonts were identified in sections of their lungs by immunohistochemical staining. Sarcocystis falcatula-like organisms were cultured from lungs of budgerigars fed sporocysts from D. marsupialis and from lungs of budgerigars fed sporocysts from 3 of 8 D. albiventris. The 33/54 locus amplified by polymerase chain reaction from culture-derived merozoites contained both a HinfI endonuclease recognition site previously suggested to diagnose S. falcatula and a DraI site thought to diagnosed S. neurona. Development of the isolate from D. marsupialis was studied in cell culture; its schizonts divided by endopolygeny, leaving a residual body. Morphological and genetic variation differentiated this Sarcocystis isolate originating in D. marsupialis from the Cornell I isolate of S. falcatula. This is the first report of a S. falcatula infection in the South American opossum, D. marsupialis. PMID:11780836

  11. Social cognition in members of conflict groups: behavioural and neural responses in Arabs, Israelis and South Americans to each other's misfortunes

    PubMed Central

    Bruneau, Emile G.; Dufour, Nicholas; Saxe, Rebecca

    2012-01-01

    In contexts of cultural conflict, people delegitimize the other group's perspective and lose compassion for the other group's suffering. These psychological biases have been empirically characterized in intergroup settings, but rarely in groups involved in active conflict. Similarly, the basic brain networks involved in recognizing others' narratives and misfortunes have been identified, but how these brain networks are modulated by intergroup conflict is largely untested. In the present study, we examined behavioural and neural responses in Arab, Israeli and South American participants while they considered the pain and suffering of individuals from each group. Arabs and Israelis reported feeling significantly less compassion for each other's pain and suffering (the ‘conflict outgroup’), but did not show an ingroup bias relative to South Americans (the ‘distant outgroup’). In contrast, the brain regions that respond to others' tragedies showed an ingroup bias relative to the distant outgroup but not the conflict outgroup, particularly for descriptions of emotional suffering. Over all, neural responses to conflict group members were qualitatively different from neural responses to distant group members. This is the first neuroimaging study to examine brain responses to others' suffering across both distant and conflict groups, and provides a first step towards building a foundation for the biological basis of conflict. PMID:22271787

  12. Topographic pharmaco-EEG mapping of the effects of the South American psychoactive beverage ayahuasca in healthy volunteers

    PubMed Central

    Riba, Jordi; Anderer, Peter; Morte, Adelaida; Urbano, Gloria; Jané, Francesc; Saletu, Bernd; Barbanoj, Manel J

    2002-01-01

    Aims Ayahuasca is a traditional South American psychoactive beverage used in Amazonian shamanism, and in the religious ceremonies of Brazilian-based syncretic religious groups with followers in the US and several European countries. This tea contains measurable amounts of the psychotropic indole N,N-dimethyltryptamine (DMT), and β-carboline alkaloids with MAO-inhibiting properties. In a previous report we described a profile of stimulant and psychedelic effects for ayahuasca as measured by subjective report self-assessment instruments. In the present study the cerebral bioavailability and time-course of effects of ayahuasca were assessed in humans by means of topographic quantitative-electroencephalography (q-EEG), a noninvasive method measuring drug-induced variations in brain electrical activity. Methods Two doses (one low and one high) of encapsulated freeze-dried ayahuasca, equivalent to 0.6 and 0.85 mg DMT kg−1 body weight, were administered to 18 healthy volunteers with previous experience in psychedelic drug use in a double-blind crossover placebo-controlled clinical trial. Nineteen-lead recordings were undertaken from baseline to 8 h after administration. Subjective effects were measured by means of the Hallucinogen Rating Scale (HRS). Results Ayahuasca induced a pattern of psychoactive effects which resulted in significant dose-dependent increases in all subscales of the HRS, and in significant and dose-dependent modifications of brain electrical activity. Absolute power decreased in all frequency bands, most prominently in the theta band. Mean absolute power decreases (95% CI) at a representative lead (P3) 90 min after the high dose were −20.20±15.23 µV2 and −2.70±2.21 µV2 for total power and theta power, respectively. Relative power decreased in the delta (−1.20±1.31% after 120 min at P3) and theta (−3.30±2.59% after 120 min at P3) bands, and increased in the beta band, most prominently in the faster beta-3 (1.00±0.88% after 90 min at P

  13. The GalileoMobile starts its South American voyage - Astronomy education goes on tour through the Andes Mountains

    NASA Astrophysics Data System (ADS)

    2009-10-01

    forward to helping the team members make the GalileoMobile a great success." To chronicle this remarkable astronomy expedition, members of the GalileoMobile team will write entries for the GalileoMobile blog and Cosmic Diary, an online blog-cum-journal that is also a Cornerstone IYA2009 project, and run a Twitter feed and a Facebook page. The team will reach out to national newspapers, websites and television stations during the tour, and will be accompanied by a film crew who will produce a multilingual documentary of the expedition. Project Coordinator Philippe Kobel concludes: "We hope that, by showing the excitement of astronomical discovery, and the diversity and richness of the South American traditions, the GalileoMobile Project will encourage a feeling of 'unity under the same sky' between people of different cultures and backgrounds." The GalileoMobile is supported by the European Southern Observatory (ESO), whose host country is Chile and which is the seat of the International Year of Astronomy 2009 (IYA2009) Secretariat, the Max Planck Society (MPG/MPE/MPA/MPS), NORDITA, Regione Molise and the Optical Society of America. Notes [1] To facilitate access to remote sites and foster the communication and translation in native non-Spanish languages, such as Quechua and Aymara, local university students or education officials will join the GalileoMobile team from time to time. More information ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role

  14. Crustal Structure of the Caribbean-South American Diffuse Plate Boundary: Subduction Zone Migration and Polarity Reversal Along BOLIVAR Profile 64W

    NASA Astrophysics Data System (ADS)

    Clark, S. A.; Levander, A.; Magnani, M.; Zelt, C. A.; Sawyer, D. S.; Ave Lallemant, H. G.

    2005-12-01

    The BOLIVAR (Broadband Ocean-Land Investigation of Venezuela and the Antilles arc Region) project is an NSF funded, collaborative seismic experiment in the southeast Caribbean region. The purpose of the project is to understand the diffuse plate boundary created by the oblique collision between the Caribbean and South American plates. Profile 64W of the BOLIVAR experiment, a 450 km-long, N-S transect onshore and offshore Venezuela located at ~64°W longitude, images the deep crustal structures formed by this collision. The active source components of profile 64W include 300 km of MCS reflection data, 33 coincident OBSs, and 344 land seismic stations which recorded 7500 offshore airgun shots and 2 explosive land shots. Results from the reflection and refraction seismic data along 64W show complex crustal structure across the entire span of the diffuse plate boundary. The onshore portion of 64W crosses the fold and thrust belt of the Serrania del Interior, which formed at ~16 Ma by collision of the Caribbean forearc with the northern South American passive margin. Underlying the Serrania del Interior is a south-vergent, remnant Lesser Antillean subduction zone. As this Lesser Antilles subduction impinged on continental crust, it caused a polarity reversal and jump offshore to the north. Convergence was initially localized in the closure and inversion of the Grenada Basin. However, subduction could not develop because of the ~20-km-thick crust of the Aves Ridge; instead, north-vergent subduction initiated further to the north, where ~12-km-thick Caribbean oceanic crust of the Venezuela Basin began to subduct beneath the Aves Ridge in the Pliocene (~4 Ma) and appears to continue subducting today. Between the remnant subduction zone and the modern one, the El Pilar and Coche dextral strike-slip faults accommodate most of the transform motion of the plate boundary. From the Serrania del Interior to the Aves Ridge, ~260 km of accreted orogenic float comprises the diffuse

  15. A strong control of the South American SeeSaw on the intra-seasonal variability of the isotopic composition of precipitation in the Bolivian Andes

    NASA Astrophysics Data System (ADS)

    Vimeux, Françoise; Tremoy, Guillaume; Risi, Camille; Gallaire, Robert

    2011-07-01

    Water stable isotopes (δ) in tropical regions are a valuable tool to study both convective processes and climate variability provided that local and remote controls on δ are well known. Here, we examine the intra-seasonal variability of the event-based isotopic composition of precipitation (δD Zongo) in the Bolivian Andes (Zongo valley, 16°20'S-67°47'W) from September 1st, 1999 to August 31st, 2000. We show that the local amount effect is a very poor parameter to explain δD Zongo. We thus explore the property of water isotopes to integrate both temporal and spatial convective activities. We first show that the local convective activity averaged over the 7-8 days preceding the rainy event is an important control on δD Zongo during the rainy season (~ 40% of the δD Zongo variability is captured). This could be explained by the progressive depletion of local water vapor by unsaturated downdrafts of convective systems. The exploration of remote convective controls on δD Zongo shows a strong influence of the South American SeeSaw (SASS) which is the first climate mode controlling the precipitation variability in tropical South America during austral summer. Our study clearly evidences that temporal and spatial controls are not fully independent as the 7-day averaged convection in the Zongo valley responds to the SASS. Our results are finally used to evaluate a water isotope enabled atmospheric general circulation model (LMDZ-iso), using the stretched grid functionality to run zoomed simulations over the entire South American continent (15°N-55°S; 30°-85°W). We find that zoomed simulations capture the intra-seasonal isotopic variation and its controls, though with an overestimated local sensitivity, and confirm the role of a remote control on δ according to a SASS-like dipolar structure.

  16. Population structure and historical demography of South American sea lions provide insights into the catastrophic decline of a marine mammal population

    PubMed Central

    Hoffman, J. I.; Kowalski, G. J.; Klimova, A.; Staniland, I. J.; Baylis, A. M. M.

    2016-01-01

    Understanding the causes of population decline is crucial for conservation management. We therefore used genetic analysis both to provide baseline data on population structure and to evaluate hypotheses for the catastrophic decline of the South American sea lion (Otaria flavescens) at the Falkland Islands (Malvinas) in the South Atlantic. We genotyped 259 animals from 23 colonies across the Falklands at 281 bp of the mitochondrial hypervariable region and 22 microsatellites. A weak signature of population structure was detected, genetic diversity was moderately high in comparison with other pinniped species, and no evidence was found for the decline being associated with a strong demographic bottleneck. By combining our mitochondrial data with published sequences from Argentina, Brazil, Chile and Peru, we also uncovered strong maternally directed population structure across the geographical range of the species. In particular, very few shared haplotypes were found between the Falklands and South America, and this was reflected in correspondingly low migration rate estimates. These findings do not support the prominent hypothesis that the decline was caused by migration to Argentina, where large-scale commercial harvesting operations claimed over half a million animals. Thus, our study not only provides baseline data for conservation management but also reveals the potential for genetic studies to shed light upon long-standing questions pertaining to the history and fate of natural populations. PMID:27493782

  17. Mapping Large-scale Turbulent Structures around the Equatorial Region Using Satellites and Ground-based Instrumentations in the South American Sector

    NASA Astrophysics Data System (ADS)

    Pradipta, R.; Valladares, C. E.; Doherty, P.

    2015-12-01

    We present the results of our experimental investigation on the physical characteristics of equatorial plasma bubbles/depletions and ionospheric disturbances over the South American sector. In this study, we used the GPS total electron content (TEC) measurements from the Low-latitude Ionospheric Sensor Network (LISN) to monitor the temporal development and map the geographic distribution of ionospheric bubbles/depletions over South America. A special TEC data detrending technique (known as the guided-rotation assisted ionospheric TEC detrender, or GRAIT-Detrender) had been developed in order to recognize the presence of bubbles/depletions, distinguishing them from wavelike structures associated with traveling ionospheric disturbances (TIDs). Using data collected from ~240 GPS receivers in the Caribbean and South America, the detrended TEC data were subsequently compiled to form a full 2-D spatial profile of the bubbles/depletions in the region. We further corroborate the compiled 2-D ΔTEC map using additional data from ground-based ionosonde measurements as well as in-situ ion density measurements from C/NOFS.

  18. Population structure and historical demography of South American sea lions provide insights into the catastrophic decline of a marine mammal population.

    PubMed

    Hoffman, J I; Kowalski, G J; Klimova, A; Eberhart-Phillips, L J; Staniland, I J; Baylis, A M M

    2016-07-01

    Understanding the causes of population decline is crucial for conservation management. We therefore used genetic analysis both to provide baseline data on population structure and to evaluate hypotheses for the catastrophic decline of the South American sea lion (Otaria flavescens) at the Falkland Islands (Malvinas) in the South Atlantic. We genotyped 259 animals from 23 colonies across the Falklands at 281 bp of the mitochondrial hypervariable region and 22 microsatellites. A weak signature of population structure was detected, genetic diversity was moderately high in comparison with other pinniped species, and no evidence was found for the decline being associated with a strong demographic bottleneck. By combining our mitochondrial data with published sequences from Argentina, Brazil, Chile and Peru, we also uncovered strong maternally directed population structure across the geographical range of the species. In particular, very few shared haplotypes were found between the Falklands and South America, and this was reflected in correspondingly low migration rate estimates. These findings do not support the prominent hypothesis that the decline was caused by migration to Argentina, where large-scale commercial harvesting operations claimed over half a million animals. Thus, our study not only provides baseline data for conservation management but also reveals the potential for genetic studies to shed light upon long-standing questions pertaining to the history and fate of natural populations. PMID:27493782

  19. Reflections on End of Life: Comparison of American Indian and Non-Indian Peoples in South Dakota

    ERIC Educational Resources Information Center

    Schrader, Susan L.; Nelson, Margot L.; Eidsness, LuAnn M.

    2009-01-01

    During the past century, dramatic changes have occurred in the way death is experienced in the United States. A death in 1900 typically occurred as a result of sudden illness and injury among the young at home. Today, Americans are more likely to die from long-term, chronic illness in later life, often in institutional settings. In addition to the…

  20. Residence Projections of Mexican-American Youth from the Border Area of South Texas: A Study of Changes Over Time.

    ERIC Educational Resources Information Center

    Monk, Phillip M.; Medina, Dennis

    The study assessed the stability or change in the residential orientations of rural Mexican American youth living near the Texas-Mexico border, examined changes in the local social and economic environment, and made some predictions as to their effects on the students' dispositions. In the springs of 1967 and 1973, questionnaires were administered…

  1. A Case Study of the Academic Achievement of African American Males in Single-Sex Classrooms in Rural South Carolina

    ERIC Educational Resources Information Center

    Pannell, Lynette Martin

    2013-01-01

    The purpose of this study was to investigate the differences of Measures of Academic Progress (MAP) scores between fourth-grade African American male students who were enrolled in single-sex classrooms and their counterparts who were enrolled in coeducational classrooms. The research provided descriptive data concerning one Title I school in rural…

  2. The GalileoMobile starts its South American voyage - Astronomy education goes on tour through the Andes Mountains

    NASA Astrophysics Data System (ADS)

    2009-10-01

    Today marks the beginning of the GalileoMobile Project, a two-month expedition to bring the wonder and excitement of astronomy to young people in Chile, Bolivia and Peru. Supported by ESO and partners, a group of astronomers and educators will travel through a region of the Andes Mountains aboard the GalileoMobile, offering astronomical activities, such as workshops for students and star parties for the general public. Professional filmmakers on the trip will produce a multilingual documentary capturing the thrill of discovery through science, culture and travel. The GalileoMobile is a Special Project of the International Year of Astronomy 2009 (IYA2009), which is a global celebration commemorating the first use of a telescope to view the Universe by the Italian astronomer Galileo four hundred years ago. The project will promote basic science education through astronomy by visiting schools and communities that have limited access to outreach programmes. The GalileoMobile will provide these underserved groups with hands-on activities and educational material from international partners. The van is fully equipped to offer unique sky-observing opportunities for young students and other locals, with star parties at night and solar observations during the day. The team will use various tools including IYA2009's handy Galileoscopes, which will be donated to the schools after the visits. By stimulating curiosity, critical thinking and a sense of wonder and discovery for the Universe and our planet, the GalileoMobile Project aims to encourage interest in astronomy and science, and exchange culturally different visions of the cosmos. Spearheading the initiative is a group of enthusiastic Latin American and European PhD students from the European Southern Observatory, the Max Planck Society, the University Observatory Munich, and the Stockholm University Observatory. This itinerant educational programme is intended to reach about 20 000 people during eight weeks in October

  3. Trilateral South-American project: a reference system for measuring electric power up to 100 kHz - progress report

    NASA Astrophysics Data System (ADS)

    Kyriazis, G. A.; Di Lillo, L.; Slomovitz, D.; Iuzzolino, R.; Yasuda, E.; Trigo, L.; Laiz, H.; Debatin, R. M.; Franco, A. M. R.; Afonso, E.

    2016-07-01

    Three countries in South America are jointly developing a reference system for measuring electric power up to 100 kHz. The objective is the construction of three similar measuring systems, one for each institute. The measuring system is described and its design requirements are presented. This project will contribute to provide calibration services in measuring ranges still not covered by the three institutes.

  4. Pod mesocarp flour of North and South American species of Leguminous tree (mesquite): Composition and food applications

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flour from the mesocarp of pods of the tree legume known as mesquite (Prosopis spp.) in North America or algarrobo in South America was one of the most important food staples for desert people. Contemporary milling techniques produces a similar flour that is about 40% sucrose, 25% dietary fiber, and...

  5. In Pursuit of the American Degree: Internationalization, National Security, and the Making of South Asian Foreign Students

    ERIC Educational Resources Information Center

    Thomas, Susan

    2013-01-01

    My dissertation examines how global neoliberal forces intersect with racialized state security practices to shape the transnational subjectivities of South Asian overseas students studying in the U.S. in the post-9/11 moment. These students' movement across national borders to pursue higher education in the United States positions them as ideal…

  6. Korea's "Model Minority": A Case Study of an American-Korean Bilingual Student's Challenges Learning English