South America

Medical Geology, the study of the impacts of geologic materials and processes on animal and human health, is a dynamic emerging discipline bringing together the geoscience, biomedical, and public health communities to solve a wide range of environmental health problems. Among the Medical Geology described in this review are examples of both deficiency and toxicity of trace element exposure. Goiter is a widespread and potentially serious health problem caused by deficiency of iodine. In many locations the deficiency is attributable to low concentrations of iodine in the bedrock. Similarly, deficiency of selenium in the soil has been cited as the principal cause of juvenile cardiomyopathy and muscular abnormalities. Overexposure to arsenic is one of the most widespread Medical Geology problems affecting more than one hundred million people in Bangladesh, India, China, Europe, Africa and North and South America. The arsenic exposure is primarily due to naturally high levels in groundwa...

Despite their perceived inaccessibility, the marine intertidal and benthic environments of Antarctica, southern Africa and South America have continued to provide marine natural products for chemists with unique opportunities to study the secondary metabolite constituents and chemical ecology of a diverse array of marine gastropod molluscs. This review covers the literature up to 31 January 2005 and describes the structures and, where applicable, biological activities of 100 secondary metabolites isolated from 21 species of marine gastropod molluscs. Not unexpectedly, the chemistry of chemically defended shell-less opisthobranchs dominates the natural product studies of molluscs collected from these regions of the southern hemisphere.

The Southern Argentina Agile Meteor Radar (SAAMER) was installed at Rio Grande on Tierra del Fuego (53.8°S, 67.8°W) in May 2008 and has been operational for ∼24 months. This paper describes the motivations for the radar design and its placement at the southern tip of South America, its operating modes and capabilities, and observations of the mean winds, planetary waves, and tides during its first ∼20 months of operation. SAAMER was specifically designed to provide very high resolution of large-scale motions and hopefully enable direct measurements of the vertical momentum flux by gravity waves, which have only been possible previously with dual-or multiple-beam radars and lidars or in situ measurements. SAAMER was placed on Tierra del Fuego because it was a region devoid of similar measurements, the latitude was anticipated to provide high sensitivity to an expected large semidiurnal tide, and the region is now recognized to be a "hot spot" of small-scale gravity wave activity extending from the troposphere into the mesosphere and lower thermosphere, perhaps the most dynamically active location on Earth. SAAMER was also intended to permit simultaneous enhanced meteor studies, including "head echo" and "nonspecular" measurements, which were previously possible only with high-power largeaperture radars. Initial measurements have defined the mean circulation and structure, exhibited planetary waves at various periods, and revealed large semidiurnal tide amplitudes and variability, with maximum amplitudes at higher altitudes often exceeding 60 m s −1 and amplitude modulations at periods from a few to ∼30 days.

Brazilian projection towards South America has been an important issue since its re democratization process in the 1980s. Still, Brazil’s regional behavior could not be considered as a hegemony, under the realist point of view, that is, exerted by its hard power. Nor liberal, considering the option for multiplicities initiatives and a low level of institutionalization. Therefore, we propose to apply the Gramscian concept of hegemony to analyze if Brazil could exert hegemony towards South America throughout its participation in regional integration processes. To do so, we have chosen to use a qualitative method of analysis along with a typical case-study to develop a prelaminar theory illustration, based upon a literature review of the Brazilian foreign policy (primary and secondary sources). This inquiry leads us to argue that there is a dubiety regarding Brazil’s regional action. Firstly, due to the lack of institutionalization of South American regional organizations and; secondly...

Some questions posed by fossil vertebrates of South America since the ®rst discoveries of the`giant's bones' are reviewed and questions of taxonomy, taphonomy, palaeoenvironment and palaeobiogeography discussed. Through time, palaeobiogeographic issues have been the dominant theme in discussions of South American vertebrates.

This article examines the relationship between information and communication technologies (ICTs) and regional integration as a pathway to socioeconomic development in Africa and South America. Both regions share a colonial legacy often characterized by stronger economic ties to the developed world than within the regions. In recent decades, regional organizations have been involved in efforts to strengthen the infrastructure for ICTs, as well as the enhancement of economic and political integration as strategies to achieve development. However, the literature continues to show distinct research agendas that unwittingly overlook the connections between these areas. This article proposes a theoretical framework combining research on integration, ICTs, and development. It provides a brief analysis of each region and its ICT initiatives, the potential impact on regional integration, and how this relates to development. We suggest possible applications of the framework to identify and research the processes of integration and expected outcomes of development.

To evaluate sex-specific differences in gene flow between Native American populations from South America and between those populations and recent immigrants to the New World, we examined the genetic diversity at uniand biparental genetic markers of five Native American populations from Colombia and in published surveys from native South Americans. The Colombian populations were typed for five polymorphisms in mtDNA, five restriction sites in the b-globin gene cluster, the DQA1 gene, and nine autosomal microsatellites. Elsewhere, we published results for seven Y-chromosome microsatellites in the same populations. Autosomal polymorphisms showed a mean G ST of 6.8%, in agreement with extensive classical marker studies of South American populations. MtDNA and Y-chromosome markers resulted in G ST values of 0.18 and 0.165, respectively. When only Y chromosomes of confirmed Amerind origin were used in the calculations (as defined by the presence of allele T at locus DYS199), G ST increased to 0.22. G ST values calculated from published data for other South American natives were 0.3 and 0.29 for mtDNA and Amerind Y chromosomes, respectively. The concordance of these estimates does not support an important difference in migration rates between the sexes throughout the history of South Amerinds. Admixture analysis of the Colombian populations suggests an asymmetric pattern of mating involving mostly immigrant men and native women.

Mahogany (Swietenia macrophylla, Meliaceae) is the most valuable and intensively exploited Neotropical tree. No information is available regarding the genetic structure of mahogany in South America, yet the region harbours most of the unlogged populations of this prized hardwood. Here we report on the genetic diversity within and the differentiation among seven natural populations separated by up to 2100 km along the southern arc of the Brazilian Amazon basin. We analysed the variation at eight microsatellite loci for 194 adult individuals. All loci were highly variable, with the number of alleles per locus ranging from 13 to 27 (mean = 18.4). High levels of genetic diversity were found for all populations at the eight loci (mean HE = 0.781, range 0.754–0.812). We found moderate but statistically significant genetic differentiation among populations considering both estimators of FST and RST, θ = 0.097 and ρ = 0.147, respectively. Estimates of θ and ρ were significantly greater than zero for all pairwise population comparisons. Pairwise ρ-values were positively and significantly correlated with geographical distance under the isolation-by-distance model. Furthermore, four of the populations exhibited a significant inbreeding coefficient. The finding of local differentiation among Amazonian mahogany populations underscores the need for in situ conservation of multiple populations of S. macrophylla across its distribution in the Brazilian Amazon. In addition, the occurrence of microgeographical genetic differentiation at a local scale indicates the importance of maintaining populations in their diverse habitats, especially in areas with mosaics of topography and soil.

Alligatorweed, (Alternanthera philoxeroides (Mart.) Griseb.), an aquatic and wetland plant native to South America, is an aggressive weed in many parts of the world. Its ability to compete with other native plants and to impede waterways has made it a serious threat to aquatic ecosystems. Although biological control with insects has been fairly successful in aquatic habitats, there is a need for additional agents to manage the weed in upland sites. Accordingly, in a survey in Brazil in 1997 a fungus, Nimbya (=Alternaria) alternantherae (Holcomb and Antonopoulus) Simmons and Alcorn, was discovered and confirmed to be highly damaging to alligatorweed. Studies were conducted to determine the potential of this fungus for controlling this weed. Several isolates from Brazil, USA, and Puerto Rico were compared and no differences in virulence were observed, although a lower dew requirement was demonstrated for the Brazilian isolates. Conidia were more effective than mycelial suspension, and inoculum concentrations of 1 • 10 5 and 1 • 10 6 conidia per ml provided significant levels of control of the weed in greenhouse and field experiments, respectively. In a host-range study, N. alternantherae infected 6 plant species from a total of 42 species belonging to 23 families. N. alternantherae has the potential to be an effective mycoherbicide for alligatorweed.

In unpolluted regions, where inorganic nitrogen (N) inputs from the atmosphere are minimal, such as remote locations in southern South America, litterfall dynamics and N use efficiency of tree species should be coupled to the internal N cycle of forest ecosystems. This hypothesis was examined in two evergreen temperate forests in southern Chile (42 Њ 30 Ј S), a mixed broad-leaved forest (MBF) and a conifer forest (CF). Although these forests grow under the same climate and on the same parental material, they differ greatly in floristic structure and canopy dynamics (slower in the CF). In both forests, biomass, N flux, and C/N ratios of fine litterfall were measured monthly from May 1995 to March 1999. There was a continuous litter flux over the annual cycle in both forests, with a peak during autumn in the CF. In the MBF, litterfall decreased during spring. In both forests, the C/N ratios of litterfall varied over the annual cycle with a maximum in autumn. Annual litterfall biomass flux (Mean ± SD = 3.3 ± 0.5 vs 2.0 ± 0.5 Mg ha -1 ) and N return (34.8 ± 16 vs 9.1 ± 2.8 kg N ha -1 ) were higher in the MBF than in the CF. At the ecosystem level, litterfall C/N was lower in the MBF (mean C/N ratio = 60.1 ± 15, n = 3 years) suggesting decreased N use efficiency compared with CF (mean C/N ratio = 103 ± 19.6, n = 3 years). At the species level, subordinated (subcanopy) tree species in the MBF had significantly lower C/N ratios (<50) of litterfall than the dominant trees in the CF and MBF (>85). The litterfall C/N ratio and percentage N retranslocated were significantly correlated and were lower in the MBF. The higher net N mineralization in soils of the MBF is related to a lower N use efficiency at the ecosystem and species level.

Recent developments in hydrological modelling of river basins are focused on prediction in ungauged basins, which implies the need to improve relationships between model parameters and easilyobtainable information, such as satellite images, and to test the transferability of model parameters. A large-scale distributed hydrological model is described, which has been used in several large river basins in Brazil. The model parameters are related to classes of physical characteristics, such as soil type, land use, geology and vegetation. The model uses two basin space units: square grids for flow direction along the basin and GRU-group response units-which are hydrological classes of the basin physical characteristics for water balance. Expected ranges of parameter values are associated with each of these classes during the model calibration. Results are presented of the model fitting in the Taquari-Antas River basin in Brazil (26 000 km 2 and 11 flow gauges). Based on this fitting, the model was then applied to the Upper Uruguay River basin (52 000 km 2 ), having similar physical conditions, without any further calibration, in order to test the transferability of the model. The results in the Uruguay basin were compared with recorded flow data and showed relatively small errors, although a tendency to underestimate mean flows was found.

Este trabalho tem por objetivo a escolha da rota marítima mais adequada para um contêiner entre dois portos. Possíveis rotas do contêiner são analisadas utilizando-se a Análise Envoltória de Dados (DEA), a composição de probabilidades de otimizar e o método de Copeland. As variáveis consideradas são tempo de transporte, produtividade e custos dos terminais portuários, tais como: armazenagem do contêiner e custo da operação de transbordo. São usados dados reais de uma empresa brasileira de transporte marítimo que possui rotas de navios fixas e regulares entre os portos da costa leste da América do Sul.

Knowledge about current patterns of genetic structure of populations together with the evolutionary history of a species helps to understand and predict the adaptation of populations to future climate change. We assayed variation at nuclear microsatellite markers among peripheral vs. continuous populations of the temperate South American species Austrocedrus chilensis, to investigate the role of historical vs. demographical forces in shaping population genetic structure. This species occurs in continuous populations in the west and central distribution range, but becomes highly fragmented at the eastern limit, which comprised ice-free areas during Quaternary glaciations and has extreme climatic conditions at present times. Bayesian analysis methods identified two contrasting patterns of genetic structure; (I) populations from humid, mesic and peri-glacial regions formed a single deme with relatively low genetic differentiation and high admixture levels whereas (II) a highly heterogeneous genetic structure with low level of admixture was found in the steppe, towards the east and northeast limit of the distribution range. In the steppe, population fragmentation, restricted gene flow and isolation-by-distance were also inferred. In addition, several small steppe populations showed high genetic diversity and divergent gene pools, suggesting that they constitute ancient refuges from pre-Holocene glaciations with just a subgroup of them contributing significantly to post-glacial spread. These results are discussed in relation to patterns of genetic variation found for other temperate species and the contribution of the particular southern Andes topography and climate to post-glacial spread.

Extracts (aqueous, methanol and dichloromethane) from Ambrosia tenuifolia, Aristolochia triangularis, Bacclraris tucumanensis, Campyloneuron phyllitidis and Eupatorium christieanum were screened for antiinflammatory activity. On the croton oil induced mouse ear oedema test, the highest activities were exhibited by dichloromethane extracts assayed, especially those of Baccharis tucumanensis and Campyloneuron phyllitidi. On the carrageenan mouse paw oedema test, Baccharis tucumanensis and Campyloneuron phyllitidis showed the highest activity.

Sporotrichosis is the most common subcutaneous mycosis in South America. Classic infection is associated with traumatic inoculation of soil, vegetables, and organic material contaminated with Sporothix schenckii. Animals of various species, including humans, are affected by this disease. This subcutaneous mycosis is an infection of implantation. The most frequent clinical form is the lymphocutaneous form. The fixed cutaneous form is characterized by infiltrated nodular, ulcerated, or erythematosquamous lesions located on exposed areas where fungal inoculation occurred. The disseminated cutaneous forms have mainly been observed among immunosuppressed patients, especially human immunodeficiency virus-positive individuals. Sporotrichosis is the only subcutaneous mycosis for which direct examination or histology is of little or no value for diagnosis. The diagnosis rests solely on the isolation of S schenckii in culture. Since 1998, researchers from Brazil suggested that feline transmis...

1] New observations obtained by the satellite CHAMP reveal a detailed picture of the noon-time equatorial electrojet (EEJ). The low orbit of CHAMP and its high-precision magnetometers reveal the spatial structure of the EEJ with unprecedented accuracy. Data from more than two and a half years have been used to investigate average features and also the global characteristics of the EEJ. Rather than interpreting the magnetic signatures, we determined the horizontal current distribution by using a very general current model (series of line currents). This makes the results independent of satellite altitude and ambient field geometry. The procedure for determining the structure of the electrojet is fully automated, giving an objective response. Some of the spatial features of the noon-time EEJ are as follows: The electrojet current peaks right at the dip equator. There is no deviation from it either on a seasonal basis or with longitude. The width of the EEJ (%4°in latitude) at half the peak value of the current density profile is for a given longitude fairly constant, independent of the amplitude. Return currents north and south of the eastward current are a common feature of the EEJ. They peak at latitudes some 5°a way from the dip equator. The intensity of the EEJ varies strongly from day to day. The average peak current density exhibits a clear dependence on longitude. Peaks show up over South America and Indonesia. The average current density follows closely the monthly mean of the solar flux index, F10.7. The total EEJ eastward current is about three times as strong as the return current. The total current and the peak current density are related to each other by a power law. This suggests that the longitude dependence of the EEJ intensity can be explained by the varying cross-sectional area of the Cowling channel.

Laboratory and glasshouse bioassays were developed in Australia and the US for evaluating wild pea (Pisum fulvum Sibth. & Sm.) accessions for resistance to pea weevil (Bruchus pisorum) (L.), one of the most important pests of cultivated pea (Pisum sativum L.) in Europe, India, North and South America and Australia. A "eld experiment and laboratory tests showed that #at and swollen P. sativum pods and pods longer than 10}20 mm in length provide optimal or near optimal oviposition substrates. Dual-choice and no-choice laboratory bioassays were then developed using excised #at and swollen pods 30}40 mm in length to screen P. fulvum accessions for pea weevil resistance. A glasshouse experiment to measure antibiosis resistance in seed demonstrated the e!ectiveness of manually transferring weevil eggs to intact pods of di!erent maturity stages on potted P. fulvum plants. The laboratory dual-choice and no-choice tests and the glasshouse bioassays are complementary and ful"ll the requirement for a reliable screening method to identify the resistance status of P. fulvum germplasm to B. pisorum.

Rainfall variability in the Amazon basin is studied in relation to sea-surface temperatures (SSTs) in the equatorial Pacific and the northern and southern tropical Atlantic during the 1977-99 period, using the HiBAm original rainfall data set and complementary cluster and composite analyses.

While evidenced-based guidelines promote glycated hemoglobin (HbA(1c)) targets &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;7.0% in order to reduce the long-term risk of diabetic complications, many individuals with type 2 diabetes do not achieve these targets. Fear of hypoglycemia provides a major barrier to improving blood glucose control as a result of delayed insulin initiation and failure to appropriately titrate insulin following initiation. Modern insulin analogs were designed to achieve improved blood glucose control with similar hypoglycemic risk compared with non-analog insulins (or similar blood glucose control with reduced hypoglycemic risk). While this has been demonstrated in randomized controlled trials, there is a need to confirm these findings in an everyday clinical setting. The A(1)chieve study will evaluate adverse events and effectiveness of premix (biphasic insulin aspart 30 [NovoMix 30]), basal (insulin detemir [Levemir]), and meal-time (insulin aspart [NovoRapid]) insulin analogs in people with type 2 diabetes in near-routine clinical practice. A(1)chieve is an international, prospective, multi-center, open-label, non-interventional, 24-week study of people with type 2 diabetes using an insulin analog. The study will recruit 60 000 people from 30 countries across four continents (Asia, Africa, South America, and Europe). The primary aim of the study is to assess the adverse event profile of the study insulins in routine clinical practice, including rates of hypoglycemia. In addition, effectiveness (HbA(1c), fasting plasma glucose, and postprandial plasma glucose) and patient quality of life outcomes will be measured. Comprehensive epidemiological data will be collected at baseline, including recent plasma glucose results and hypoglycemic episodes, prevalence of diabetes-related complications, and measures of current standards of care. Thus, A(1)chieve should provide important information about how insulin analogs perform in daily clinical practice.

A granulovirus (GV) isolated from Epinotia aporema (Lepidoptera: Tortricidae)—a major soybean pest—was studied in terms of its main morphological, biochemical, and biological properties. The ovoidal occlusion bodies were 466 by 296 nm in size, and their most prominent protein had an apparent molecular mass of 29 kDa. Its amino-terminal sequence was remarkably homologous to that of the granulins of other GVs. The DNA genome size was estimated to be 120 kbp. The high specificity and pathogenicity of this newly described granulovirus (EpapGV) indicate that it is indeed a good candidate for the biological control of this pest.

The paper presents results on the use of NOAA AVHRR data for desertification monitoring on a regionalglobal level. It is based on processing of the GIMMS 8 km global NDVI data set. Time series of annually integrated and standardized annual NDVI anomalies were generated and compared with a corresponding rainfall data set (1981-2003). The regions studied include the Mediterranean basin, the Sahel from the Atlantic to the Red Sea, major parts of the drylands of Southern Africa, China-Mongolia and the drylands of South America, i.e. important parts of the desertification prone drylands of the world. It is concluded that the suggested methodology is a robust and reliable way to assess and monitor vegetation trends and related desertification on a regional-global scale. A strong general relationship between NDVI and rainfall over time is demonstrated for considerable parts of the drylands. The results of performed trend analysis cannot be used to verify any systematic generic land degradation/desertification trend at the regional-global level. On the contrary, a "greening-up" seems to be evident over large regions.

When I moved to Chile more than a decade ago, I experienced a professional crisis. What would a security expert do in Chile, one of the safest countries in Latin America? For a long time I had lived in Argentina and Peru, where increasing problems of violence and crime had shaped my interest on issues of police brutality, corruption, organized crime and community participation in crime prevention initiatives. However, Chilean society didn't seem to be facing any of these problems: Chile had one of the lowest homicide rates in the hemisphere and its police institutions were regarded as highly professional.

Seagrasses, marine flowering plants, are widely distributed along temperate and tropical coastlines of the world. Seagrasses have key ecological roles in coastal ecosystems and can form extensive meadows supporting high biodiversity. The global species diversity of seagrasses is low (< 60 species), but species can have ranges that extend for thousands of kilometers of coastline. Seagrass bioregions are defined here, based on species assemblages, species distributional ranges, and tropical and temperate influences. Six global bioregions are presented: four temperate and two tropical. The temperate bioregions include the Temperate North Atlantic, the Temperate North Pacific, the Mediterranean, and the Temperate Southern Oceans. The Temperate North Atlantic has low seagrass diversity, the major species being Zostera marina, typically occurring in estuaries and lagoons. The Temperate North Pacific has high seagrass diversity with Zostera spp. in estuaries and lagoons as well as Phyllospadix spp. in the surf zone. The Mediterranean region has clear water with vast meadows of moderate diversity of both temperate and tropical seagrasses, dominated by deep-growing Posidonia oceanica. The Temperate Southern Oceans bioregion includes the temperate southern coastlines of Australia, Africa and South America. Extensive meadows of low-to-high diversity temperate seagrasses are found in this bioregion, dominated by various species of Posidonia and Zostera. The tropical bioregions are the Tropical Atlantic and the Tropical Indo-Pacific, both supporting mega-herbivore grazers, including sea turtles and sirenia. The Tropical Atlantic bioregion has clear water with a high diversity of seagrasses on reefs and shallow banks, dominated by Thalassia testudinum. The vast Tropical Indo-Pacific has the highest seagrass diversity in the world, with as many as 14 species growing together on reef flats although seagrasses also occur in very deep waters. The global distribution of seagrass genera is remarkably consistent north and south of the equator; the northern and southern hemispheres share ten seagrass genera and only have one unique genus each. Some genera are much more speciose than others, with the genus Halophila having the most seagrass species. There are roughly the same number of temperate and tropical seagrass genera as well as species. The most widely distributed seagrass is Ruppia maritima, which occurs in tropical and temperate zones in a wide variety of habitats. Seagrass bioregions at the scale of ocean basins are identified based on species distributions which are supported by genetic patterns of diversity. Seagrass bioregions provide a useful framework for interpreting ecological, physiological and genetic results collected in specific locations or from particular species.

DNA sequences of Amblyomma aureolatum (Pallas, 1772) and Amblyomma ovale Koch, 1844 were obtained to determine genetic differences between these tick species. Collections of these species are discussed in relation to distribution and hosts. Seven ticks collections (four from Brazil, one from Argentina, one from Uruguay and one from USA) house a total of 1272 A. aureolatum (224 males, 251 females, 223 nymphs and 574 larvae) and 1164 A. ovale (535 males, 556 females, 66 nymphs and 7 larvae). The length of the sequenced mitochondrial 16S rRNA gene fragment for A. aureolatum was 370 bp and for A. ovale was 373 bp. The DNA sequence analysis showed a 13.1% difference between the two species. Apart from one male A. ovale found on a toad, all adult ticks were found on mammals. The majority of adult specimens of both tick species were removed from Carnivora (96.1 and 84.3% of A. aureolatum and A. ovale, respectively), especially from dogs A.A. Guglielmone et al. / Veterinary Parasitology 113 (2003) [273][274][275][276][277][278][279][280][281][282][283][284][285][286][287][288] (53.1% of A. aureolatum, and 46.4% of A. ovale). Collections on wild Canidae were higher for A. aureolatum (23.3%) than for A. ovale (7.1%). On the other hand, collections of A. ovale adults on wild Felidae were higher (18.3%) than findings of A. aureolatum (9.2%). The contribution of other mammalian orders as hosts for adults of A. aureolatum and A. ovale was irrelevant, with the exception of Perissodactyla because Tapiridae contributed with 13.0% of the total number of A. ovale adults. Adults of both tick species have been found occasionally on domestic hosts (apart of the dog) and humans. Most immature stages of A. aureolatum were found on Passeriformes birds, while rodents and carnivores were the most common hosts for nymphs and larvae of A. ovale. A. aureolatum has been found restricted to the Neotropical region, covering the eastern area of South America from Uruguay to Surinam, including northeastern Argentina, eastern Paraguay, southeastern Brazil and French Guiana. A. ovale showed a distribution that covers the Neotropical region from central-northern Argentina throughout the Neotropics into the Nearctic region of Mexico with a few records from the USA, also with collection sites in Paraguay

... KINZEY et al. found that in mixed species groups of Callicebus torquatus and Saguinus fuseieollis, the more quadrupedal titi monkey, C. torquatus, always moved higher in the canopy than the more saltatory tamarin, S. fuseieollis (KINZEY et al., 1977; KINZEY, pers. comm.). ...

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Although international protection has been granted since 1935, southern right whales have only recently shown signs of recovery, possibly due to anthropogenic factors. Off Brazil, illegal hunting of right whales occurred until 1973. This paper reports on surveys conducted along the southern Brazilian coast and the information recovered on right whale strandings for this area from 1977-1995. In the first 10 years of this period only four cases were registered. However, in contrast, 20 cases were counted during the last nine years. These results are discussed in relation to marine traffic and the fisheries in the area that produce risks of collision and entanglement. Further, the possibility of storm surges being a preponderant factor in the mortalities in this area is presented. These yearly rates are compared with neighbouring areas that are also inhabited by the right whales. Both possibilities fit the hypothesis that the right whales using the Brazilian coast for breeding may finally be showing signs of recovery.

The Romeral Fault System (RFS) extends 1600 km from Barranquilla-Colombia to Talara city-Peru and before the Pliocene. In the Middle Eocene RFS defi ned the northwestern border of the South America plate, being originated by a triple junction rift- rift- rift occurred from lower to middle Jurassic, when the South American sector separated from Chortis, Oaxaca and Yucatan blocks. From Late Mesozoic until Early Paleocene, the Paleo Pacifi c plate converged on NW South America corner being subducted when an anomalous thick oceanic crust, represented by the Caribbean plate, was accreted extinguishing gradually from the North of Peru to the North of Colombia. The collision generated a transtensive fi eld stress in back arc region, due to the ancestral Central Cordillera rising in continental border. The RFS rocks suffered low grade metamorphism and some rocks of extinct subduction zone suffered metamorphic inversion. During Late Paleogene until Early Miocene, the convergence South Americ...

Extensional processes that followed the Gondwanan Orogeny rise to the development of a series of rift basins along the continental margin over older accreted Eopaleozoic terranes. Stratigraphic, structural, paleontological, and isotopic studies are presented in this work in order to constrain the ages of the sedimentary infilling and to analyze the tectosedimentary evolution of one of the Cuyo basin depocenters, known as Rincón Blanco. This asymmetrical half-graben was filled by continental sediments under a strong tectonic ...

Plate tectonic reconstructions for the Cretaceous have assumed that the major continental blocks-Eurasia, the Late Cretaceous the Atlantic-Indian Ocean complex was a long, narrow, sinuous ocean basin extending off the Tethys and around Africa.

Ponencia en  Seminario Memoria, conflicto y coexistencia: Interculturalidad y descolonization en América Latina y el mundo, Santiago, Chile, 16 diciembre, 2015.

Aunque la Guerra del Pacifico terminó en 1883, Bolivianos, Peruanos, y Chilenos siguen disputando las fronteras trazadas en su final. Mientras retos se disputan en el Corte Internacional de Justicia en La Haya, los comentarios del publico y los discursos sobre estas fronteras y su significado suceden en diversas esferas públicas. Estas esferas públicas y media han cambiado radicalmente en los 132 años desde cuando se establecieron las fronteras, y hoy en día las redes sociales es un sitio clave donde Bolivianos y Chilenos de la región norte expresan las memorias (colectivamente imaginado) de formaciones políticas del pasado y sus sentimientos personales sobre el disputo en el contexto de la política actual. Esta presentación analiza texto y los memes que combinan imagines con texto posteados en Facebook por Chilenos del norte y Bolivianos, junto con los comentarios de sus amigos y conocidos. Mientras Bolivianos apelan a un sentimiento de soberanía histórica, y los Chilenos se burlan de la falta de mar de Bolivia como indicador de subdesarrollo, ambos grupos usan el humor para abordar el tema, a menudo en formas despolitizado. Considerando las redes sociales como un sitio clave donde se expresa la memoria, a pesar del reciente desarrollo de este medio, también la presentación abre conversaciones sobre como perdura la memoria mientras los portajes en donde está expresada siempre cambian, y el uso de humor en memorias de conflictos como una manera para despolitizar los temas profundamente divisivas.

We studied the ecology of Trachylepis atlantica, the easternmost native lizard species in South America, endemic to the Fernando de Noronha archipelago, approximately 350 km off the northeastern coast of Brazil. Activity of this species extended from dawn to dusk, with a peak from 1200-1400 h. Mean body temperature of active T. atlantica was 32.2 6 2.9uC and was significantly related to both air and substrate temperatures. Trachylepis atlantica used most types of available substrates in the area but was found most frequently (72.5% of observations) on rocks and normally used perches up to 80 cm high. There was sexual dimorphism in body size, with males larger than females. Trachylepis atlantica had an omnivorous diet, with plant material comprising 77% of the volume ingested and being present in 67% of stomachs with food. Formicidae and insect larvae were the main animal items in the diet. Mean prey volume (6.9 6 5.3 mm 3 ) was small compared to other related species. This, coupled with the high plant consumption, suggests that local availability of suitable prey may be limited, as expected for small islands in general.

Two factors combine in this age of globalization to favor the establishment of alien species in natural environments: human activities and global climate change. This paper reviews the recent invasion of the golden mussel, Limnoperna fortunei, in South America, including its impacts in natural and human environments. This case study allows the identification of the likely impacts that morphologically and functionally similar invasive species will have in similar environments, such as in North America, which is considered to be at high risk of invasion by L. fortunei.

Comparison of the common floristic elements between the West Indies and the surrounding continents shows a mosaic of affinities that are stronger to Central America and South America as a whole than with either one of them separately or with North America. However, since only 28% of the total West Indian seed plant flora is shared with other geographic regions of the world, the referred exercise is of limited value. Numerous tables are provided to show the distribution of genera throughout the archipelago. The application of phylogenetic studies into the service of biogeography is herein regarded as the next necessary step in elucidating the origins and affinities of the West Indian flora. Resumen El estudio comparativo de los elementos florísticos que existen en común entre las Indias Occidentales y los continentes circundantes muestran un mosaico de afinidades más cercanas a Centro América y Sur América en su totalidad, que con cualquiera de ellos por separado o con Norte América. Sin embargo, este estudio es de valor limitado ya que solo el 28% del total de la flora de plantas con semillas en las Indias Occidentales es compartido con otras regiones del mundo. En este estudio, se muestran numerosas tablas resumiendo los valores de endemismos, la distribución de los géneros dentro y fuera del archipiélago, así como los géneros más especiosos. La utilización de estudios filogenéticos al servicio de la biogeografía en las Indias Occidentales es considerado como el próximo paso esencial para la elucidación del origen y de las afinidades de la flora Antillana.