Climatic simulations of the eastern Andes low-level jet and its dependency on convective parameterizations

The South American low level jet (SALLJ) of the Eastern Andes is investigated with Regional Climate Model version 3 (RegCM3) simulations during the 2002-2003 austral summer using two convective parameterizations (Grell and Emanuel). The simulated SALLJ is compared with the special observations of SALLJEX (SALLJ Experiment). Both the Grell and Emanuel schemes adequately simulate the low level flow over South America. However, there are some intensity differences. Due to the larger (smaller) convective activity, the Emanuel (Grell) scheme simulates more intense (weaker) low level wind than analysis in the tropics and subtropics. The objectives criteria of Sugahara (SJ) and Bonner (BJ) were used for LLJ identification. When applied to the observations, both criteria suggest a larger frequency of the SALLJ in Santa Cruz, followed by Mariscal, Trinidad and Asuncin. In Mariscal and Asuncin, the diurnal cycle indicates that SJ occurs mainly at 12 UTCs (morning), while the BJ criterion presents the SALLJ as more homogenously distributed. The concentration into two of the four-times-a-day observations does not allow conclusions about the diurnal cycle in Santa Cruz and Trinidad. The simulated wind profiles result in a lower than observed frequency of SALLJ using both the SJ and BJ criteria, with fewer events obtained with the BJ. Due to the stronger simulated winds, the Emanuel scheme produces an equal or greater relative frequency of SALLJ than the Grell scheme. However, the Grell scheme using the SJ criterion simulates the SALLJ diurnal cycle closer to the observed one. Although some discrepancies between observed and simulated mean vertical profiles of the horizontal wind are noted, there is large agreement between the composites of the vertical structure of the SALLJ, especially when the SJ criterion is used with the Grell scheme. On an intraseasonal scale, a larger southward displacement of SALLJ in February and December when compared with January has been noted. The Grell and Emanuel schemes simulated this observed oscillation in the low-level flow. However, the spatial pattern and intensity of rainfall and circulation anomalies simulated by the Grell scheme are closer to the analyses than those obtained with the Emanuel scheme.

Reappraisal of the effective elastic thickness for the sub-Andes using 3-D finite element flexural modelling, gravity and geological constraints

P>Estimates of effective elastic thickness (T(e)) for the western portion of the South American Plate using, independently, forward flexural modelling and coherence analysis, suggest different thermomechanical properties for the same continental lithosphere. We present a review of these T(e) estimates and carry out a critical reappraisal using a common methodology of 3-D finite element method to solve a differential equation for the bending of a thin elastic plate. The finite element flexural model incorporates lateral variations of T(e) and the Andes topography as the load. Three T(e) maps for the entire Andes were analysed: Stewart & Watts (1997), Tassara et al. (2007) and Perez-Gussinye et al. (2007). The predicted flexural deformation obtained for each T(e) map was compared with the depth to the base of the foreland basin sequence. Likewise, the gravity effect of flexurally induced crust-mantle deformation was compared with the observed Bouguer gravity. T(e) estimates using forward flexural modelling by Stewart & Watts (1997) better predict the geological and gravity data for most of the Andean system, particularly in the Central Andes, where T(e) ranges from greater than 70 km in the sub-Andes to less than 15 km under the Andes Cordillera. The misfit between the calculated and observed foreland basin subsidence and the gravity anomaly for the Maranon basin in Peru and the Bermejo basin in Argentina, regardless of the assumed T(e) map, may be due to a dynamic topography component associated with the shallow subduction of the Nazca Plate beneath the Andes at these latitudes.

The Usefulness of Caries Frequency, Depth, and Location in Determining Cariogenicity and Past Subsistence: A Test on Early and Later Agriculturalists From the Peruvian Coast

Dental markers have been used to unravel particularities of paleodiet, subsistence, social structure, and health. This article aims to compare oral pathology among four pre-Columbian groups with different degrees of agricultural and socio-cultural development but comparable ecological conditions who lived on the coastal desert of Peru. Three of these groups are assigned to distinct phases of the Formative Period (2500-1 BC), a time critical for our understanding of the development of agriculture and social complexity. The fourth group corresponds to the Late Intermediate Period (1000-1470 AD), when agriculture had its apogee and society was highly stratified. In this study we test whether there is an increase (1) in the frequency of carious lesions and (2) in caries depth, and (3) if there is a shift from occlusal to extra-occlusal caries locations with the development of agriculture. Therefore, we analyze the frequencies of carious lesions and antemortem tooth loss (AMTL), the caries distributions by age, sex, and type of tooth, as well as the tissues affected by, and the location of the carious lesions. Since there are no significant differences in the frequencies of carious lesions and AMTL between the groups, we reject hypothesis 1. In contrast, caries depth does increase, and caries location changes from occlusal to extra-occlusal sites with agricultural development. However, we can only corroborate hypothesis 2 and 3 when taking into consideration dental wear. Thus, we recommend that caries depth and locations should be used with evaluations of dental wear to reconstruct subsistence in ancient populations. Am J Phys Anthropol 143:75-91, 2010. (C) 2010 Wiley-Liss, Inc.

Out of Amazonia again and again: episodic crossing of the Andes promotes diversification in a lowland forest flycatcher

Most Neotropical lowland forest taxa occur exclusively on one side of the Andes despite the availability of appropriate habitat on both sides. Almost all molecular phylogenies and phylogenetic analyses of species assemblages (i.e. area cladograms) have supported the hypothesis that Andean uplift during the Late Pliocene created a vicariant barrier affecting lowland lineages in the region. However, a few widespread plant and animal species occurring in lowland forests on both sides of the Andes challenge the generality of this hypothesis. To understand the role of the Andes in the history of such organisms, we reconstructed the phylogeographic history of a widespread Neotropical flycatcher (Mionectes oleagineus) in the context of the other four species in the genus. A molecular phylogeny based on nuclear and mitochondrial sequences unambiguously showed an early basal split between montane and lowland Mionectes. The phylogeographic reconstruction of lowland taxa revealed a complex history, with multiple cases in which geographically proximate populations do not represent sister lineages. Specifically, three populations of M. oleagineus west of the Andes do not comprise a monophyletic clade; instead, each represents an independent lineage with origins east of the Andes. Divergence time estimates suggest that at least two cross-Andean dispersal events post-date Andean uplift.

Unraveling an antique subduction process from metamorphic basement around Medellin city, Central Cordillera of Colombian Andes

In the surroundings of Caldas and El Retiro cities (Colombia) metamorphic rocks derived from basic and pelitic protoliths comprise the Caldas amphibole schist and the Ancon schist respectively. Subordinated metamorphosed granite bodies (La Miel gneiss) are associated to these units, and The El Retiro amphibolites, migmatites and granulites crops out eastwards of these units, separated by shear zones. The Caldas amphibole schist and the Ancon schist protoliths could have been formed in a distal marine reduced environment and amalgamated to the South American continent in an apparent Triassic subduction event. The El Retiro rocks are akin to a continental basement and possible include impure metasediments of continental margin, whose metamorphism originated granulite facies rocks and migmatites as a result of the anatexis of quartz-feldspathic rocks. The metamorphism was accompanied by intense deformation, which has juxtaposed both migmatites and granulite blocks. Afterward, heat and fluid circulation associated with the emplacement of minor igneous intrusions resulted in intense fluid-rock interaction, variations in the grain size of the minerals and, especially, intense retrograde metamorphic re-equilibrium. Thermobarometric estimations for the Caldas amphibole schist indicate metamorphism in the Barrovian amphibolite fades. The metamorphic path is counter-clockwise, but retrograde evolution could not be precisely defined. The pressures of the metamorphism in these rocks range from 6.3 to 13.5 kbar, with narrow temperature ranging from 550 to 630 degrees C. For the Ancon schist metapelites the P-T path is also counter-clockwise, with a temperature increase evidenced by the occurrence of sillimanite and the cooling by later kyanite. The progressive metamorphism event occurred at pressures of 7.6-7.2 kbar and temperatures of 645-635 degrees C for one sample and temperature between 500 and 600 degrees C under constant pressure of 6 kbar. The temperature estimated for these rocks varies between 400 and 555 degrees C at pressures of 5-6 kbar in the retrograde metamorphic path. The El Retiro rocks evidence strong decompression with narrow variation in temperature, showing pressure values between 8.7 and 2.7 kbar at temperatures of 740-633 degrees C. These metamorphic fragments of the basement in the Central Cordillera of the Colombian Andes could represent a close relationship with an antique subduction zone. (C) 2011 Elsevier Ltd. All rights reserved.

Preferências comerciais unilaterais: cooperação ou coerção?: o caso do programa de preferências comerciais para os Andes

O princípio da não-discriminação no tratamento entre os membros da OMC é um dos pilares do sistema multilateral de comércio. Esta regra geral acomoda, entretanto, uma série de mecanismos de exceção, entre os quais a autorização para que os países concedam preferências comerciais de forma unilateral. Grande parte da literatura sobre os programas de preferências comerciais unilaterais tende a enfatizar os elementos puramente econômicos, sendo pouco explorados os aspectos políticos relacionados a estes programas. Este trabalho centra-se na análise do programa de preferências comerciais unilaterais, criado pela Andean Trade Preference Act de 1991, pelo qual os Estados Unidos concedem preferencias unilaterais à Bolívia, Colômbia, Equador e Peru. Apesar do seu objetivo oficial ser o auxílio à diversificação das exportações dos beneficiários e diminuição do cultivo de culturas ligadas à produção de drogas, a avaliação desenvolvida neste trabalho não identificou efeitos significativos do programa sobre a diversificação das exportações ou produção de coca e cocaína. Verifica-se, por outro lado, que embora não seja exigida reciprocidade dos beneficiários em matéria tarifária, os Estados Unidos vinculam a outorga a uma série de condicionalidades de natureza comercial e não-comercial, como propriedade intelectual, direitos trabalhistas e proteção aos investidores, as quais refletem interesses específicos norte-americanos. A conclusão do estudo é de que a importância da ATPA não pode ser explicada pelo aspecto estritamente comercial. A existência do programa e sua renovação em 2002 são mais compreensíveis quando o analisamos como um instrumento de política externa dos Estados Unidos, pelo qual este país estabelece vínculos comerciais como forma de exercício de coerção suave sobre os beneficiários.

The impact of corporate social responsibility on the Peruvian consumer’s purchasing behavior

This exploratory research aims to find out the extent to which Corporate Social Responsibility (CSR) impacts the purchasing behavior of Peruvian consumers when it comes to convenience food products. The study includes qualitative and quantitative analysis. Qualitative analysis consists of in-depth interviews with CSR representatives from consumer product companies, CSR practitioners and some consumers from the quantitative sample. That group’s composition was selected in order to obtain a wide picture of the consumers’ perception towards CSR, including their understanding of the concept and the relevance in their decision making process when buying convenience food products. The quantitative analysis portion consists of an on-line survey focused on Peruvian consumers who live in Lima during the year 2015. Consumers included in the sample were selected by convenience. After analyzing the 134 completed surveys, the results obtained suggest that even though there is an increasing interest in CSR, including CSR as an attribute of the purchased goods, interest is not fully demonstrated by the purchasing behavior of consumers. The main breach leading to this inconsistency appears to be the lack of or failure in the companies’ CSR communication towards consumers. Consumers demand reliable information which socially responsible companies usually provide; however at this stage, the target audiences of such information are mostly corporations and communities surrounding the manufacturing plants of convenience food products.

Da Amazônia ao Pacífico cruzando os Andes

A Área Amazônica (AA) é compartilhada por oito países sul-americanos independentes. Desde os tempos coloniais sentiu-se a necessidade da construção de uma via de união da AA com o Oceano Pacífico. Mas os Andes, em termos técnicos e econômicos, foram barreira insuperável até as últimas décadas do século XIX. Nos últimos anos, para o Brasil - país que tem perto de 60% da AA -, esta via vem se tornando cada vez mais importante em termos de exportação, especialmente para o mercado japonês, de grãos, madeira, polpa de madeira etc., ao mesmo tempo em que o Japão também deseja acesso direto à AA. Brasil e Peru, segundo país da AA, com a maior e mais ocidental costa no Pacífico, têm desenvolvido projetos para a construção de uma estrada, contando para isso com apoio financeiro oferecido pelo Japão em diversas oportunidades. Tais projetos tentam conciliar não apenas os interesses de Brasil e Peru, mas também os da Bolívia, país mediterrâneo que poderia finalmente ter acesso livre à costa do Pacífico. Os Estados Unidos, porém, opõem-se a construção da mencionada via e, o projeto está a espera de que o financiamento anteriormente aventado permita sua concretização. Parece que, na construção da projetada estrada, interesses estratégicos das grandes potências mundiais estão envolvidos.

Highly polymorphic in silico-derived microsatellite loci in the potato-infecting fungal pathogen Rhizoctonia solani anastomosis group 3 from the Colombian Andes

Fourteen polymorphic microsatellite DNA markers derived from the draft genome sequence of Rhizoctonia solani anastomosis group 3 (AG-3), strain Rhs 1AP, were designed and characterized from the potato-infecting soil fungus R. solani AG-3. All loci were polymorphic in two field populations collected from Solanum tuberosum and S. phureja in the Colombian Andes. The total number of alleles per locus ranged from two to seven, while gene diversity (expected heterozygosity) varied from 0.11 to 0.81. Considering the variable levels of genetic diversity observed, these markers should be useful for population genetic analyses of this important dikaryotic fungal pathogen on a global scale.

Abiotic modulators of Podocnemis unifilis (Testudines: Podocnemididae) abundances in the Peruvian Amazon

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Structural Characterization of Peruvian Carrot (Arracacia xanthorrhiza) Starch and the Effect of Annealing on Its Semicrystalline Structure

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Characterization of native and oxidized starches of two varieties of Peruvian carrot (Arracacia xanthorrhiza, B.) from two production areas of Paraná state, Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Ecosistema del pastoreo andino en las tierras altas de los Andes Centrales

Incluye Bibliografía

Capital social e intensificación de las estrategias de vida: organizaciones locales e islas de sostenibilidad en los Andes rurales

Incluye Bibliografía