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Florencia, Colombia

The University of the Amazon , also called Uniamazonía, is a public, national, coeducational university based in the city of Florencia, Caquetá, Colombia. Wikipedia.

Recharte Uscamaita M.,University of the Amazon | Bodmer R.,University of Kent

The giant otter Pteronura brasiliensis was hunted almost to extinction in the Peruvian Amazon during a period of professional trade in wild animal skins during 1920-1973. In 1973 the Department of Agriculture of Peru (INRENA) prohibited commercial hunting in the Peruvian Amazon, and the giant otter was included in Appendix I of CITES. From 1973 to 2004 giant otter populations experienced a slow recovery in numerous rivers of the Peruvian Amazon. Here, we report the population growth of the giant otter on the Yavarí- Mirín and Yavar Rivers in north-east Peru. The first evaluations of giant otter populations in these rivers, in which no individuals were sighted, were in 1992-1993. During surveys in 1996 and 1997 two individuals were sighted. In 2001, 19 individuals were sighted and in 2003 and 2004, 41 individuals were observed. This increase demonstrates a slow recovery and shows that the population has not yet reached its carrying capacity. The prohibition of international trade in otter skins by CITES, supported by INRENA, helped the population recover and was important in the conservation of this species. © 2009 Fauna & Flora International. Source

Sutton P.L.,New York University | Torres L.P.,University of the Amazon | Branch O.H.,New York University
Malaria Journal

Background: The aim of this study was to consider the impact that multi-clone, complex infections have on a parasite population structure in a low transmission setting. In general, complexity of infection (minimum number of clones within an infection) and the overall population level diversity is expected to be minimal in low transmission settings. Additionally, the parasite population structure is predicted to be clonal, rather than sexual due to infrequent parasite inoculation and lack of recombination between genetically distinct clones. However, in this low transmission of the Peruvian Amazon, complex infections are becoming more frequent, in spite of decreasing infection prevalence. In this study, it was hypothesized that sexual recombination between distinct clonal lineages of Plasmodium falciparum parasites were altering the subpopulation structure and effectively maintaining the population-level diversity. Methods. Fourteen microsatellite markers were chosen to describe the genetic diversity in 313 naturally occurring P. falciparum infections from Peruvian Amazon. The population and subpopulation structure was characterized by measuring: clusteredness, expected heterozygosity (He), allelic richness, private allelic richness, and linkage disequilibrium. Next, microsatellite haplotypes and alleles were correlated with P. falciparum merozoite surface protein 1 Block 2 (Pfmsp1-B2) to examine the presence of recombinant microsatellite haplotypes. Results: The parasite population structure consists of six genetically diverse subpopulations of clones, called "clusters". Clusters 1, 3, 4, and 6 have unique haplotypes that exceed 70% of the total number of clones within each cluster, while Clusters 2 and 5 have a lower proportion of unique haplotypes, but still exceed 46%. By measuring the He, allelic richness, and private allelic richness within each of the six subpopulations, relatively low levels of genetic diversity within each subpopulation (except Cluster 4) are observed. This indicated that the number of alleles, and not the combination of alleles, are limited. Next, the standard index of association (IA S) was measured, which revealed a significant decay in linkage disequilibrium (LD) associated with Cluster 6, which is indicative of independent assortment of alleles. This decay in LD is a signature of this subpopulation approaching linkage equilibrium by undergoing sexual recombination. To trace possible recombination events, the two most frequent microsatellite haplotypes observed over time (defined by either a K1 or Mad20) were selected as the progenitors and then potential recombinants were identified in within the natural population. Conclusions: Contrary to conventional low transmission models, this study provides evidence of a parasite population structure that is superficially defined by a clonal backbone. Sexual recombination does occur and even arguably is responsible for maintaining the substructure of this population. © 2011 Sutton et al; licensee BioMed Central Ltd. Source

Guagliardo S.A.,Emory University | Barboza J.L.,University of the Amazon | Morrison A.C.,University of California at Davis | Astete H.,Naval Medical Research Unit No 6 Namru 6 Iquitos Laboratory | And 4 more authors.
PLoS Neglected Tropical Diseases

Background and Objectives: In the Peruvian Amazon, the dengue vector Aedes aegypti is abundant in large urban centers such as Iquitos. In recent years, it has also been found in a number of neighboring rural communities with similar climatic and socioeconomic conditions. To better understand Ae. aegypti spread, we compared characteristics of communities, houses, and containers in infested and uninfested communities. Methods: We conducted pupal-demographic surveys and deployed ovitraps in 34 communities surrounding the city of Iquitos. Communities surveyed were located along two transects: the Amazon River and a 95km highway. We calculated entomological indices, mapped Ae. aegypti presence, and developed univariable and multivariable logistic regression models to predict Ae. aegypti presence at the community, household, or container level. Results: Large communities closer to Iquitos were more likely to be infested with Ae. aegypti. Within infested communities, houses with Ae. aegypti had more passively-filled containers and were more often infested with other mosquito genera than houses without Ae. aegypti. For containers, large water tanks/drums and containers with solar exposure were more likely to be infested with Ae. aegypti. Maps of Ae. aegypti presence revealed a linear pattern of infestation along the highway, and a scattered pattern along the Amazon River. We also identified the geographical limit of Ae. aegypti expansion along the highway at 19.3 km south of Iquitos. Conclusion: In the Peruvian Amazon, Ae. aegypti geographic spread is driven by human transportation networks along rivers and highways. Our results suggest that urban development and oviposition site availability drive Ae. aegypti colonization along roads. Along rivers, boat traffic is likely to drive long-distance dispersal via unintentional transport of mosquitoes on boats. © 2014. Source

Halsey E.S.,Us Naval Medical Research Unit No 6 | Siles C.,Us Naval Medical Research Unit No 6 | Guevara C.,Us Naval Medical Research Unit No 6 | Vilcarromero S.,Us Naval Medical Research Unit No 6 | And 4 more authors.
Emerging Infectious Diseases

During 2010-2013, we recruited 16 persons with confirmed Mayaro virus infection in the Peruvian Amazon to prospectively follow clinical symptoms and serologic response over a 12-month period. Mayaro virus infection caused long-term arthralgia in more than half, similar to reports of other arthritogenic alphaviruses. Source

Mosquera O.,Laboratory of Analytical Services | Buurman P.,Wageningen University | Ramirez B.L.,University of the Amazon | Amezquita M.C.,Fundacion Universitaria Catolica

To evaluate the effect of land use change on soil organic carbon, the carbon contents and stocks of primary forest, degraded pasture, and four improved pasture systems in Colombian Amazonia were compared in a flat and a sloping landscape. The improved pastures were Brachiaria humidicola, and Brachiaria decumbens, either in monoculture or in combination with native legumes. The age of the treatments was 30years for degraded pasture and 10 or 15years for each of the improved pastures. Carbon fractions were Total C, Oxidizable C, and Non-Oxidizable (stable) C. Stocks were compared using a fixed soil mass base. The degraded pasture in the flat landscape was abandoned and dominated by weeds, while that in the sloping area was overgrazed. The latter had much lower C stocks than the former. B. humidicola monoculture had the highest stocks both in flat and sloping areas, while the effect of the other three treatments varied. C replacement based on δ 13C indicated that after 30years, the degraded pasture still contained more than 50% forest-derived C in its topsoil. The fraction in the topsoil that is not replaced roughly coincides with the Stable C fraction δ 13C values suggest that the changes in carbon stocks ascribed to differences in land use may be - at least partially - inherited from the previous land use, thus confusing the interpretation of land use effects. Nevertheless, the introduction of improved pastures on degraded grassland is a feasible alternative of land use both for carbon sequestration and as an attractive economic alternative to farmers. © 2012 Elsevier B.V. Source

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