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Posadas, Argentina

The National University of Misiones is a public university in Argentina; founded by the law 20.286 on April 16, 1973, as part of the Taquini plan, a program of reorganization of the top education that would take the foundation of universities of Jujuy, La Pampa, Lomas de Zamora, Entre Ríos, Luján, Catamarca, Salta, San Juan, San Luis y Santiago del Estero, form to more than 11.000 pupils, between them numerous foreigners, given their border location with Paraguay and Brazil. It has a publishing house and a radio station, LRH301 FM Universidad Nacional de Misiones, that streams in Ogg Vorbis format. Wikipedia.

Faunistic studies, with a taxonomically complete inventory of species, provide an important source of quantitative compiled information for several and specific regions. This information can be used in diversity analysis and has great potential in setting conservation priorities. In this study, I used the relatively well known salticid spider fauna of Misiones to generate Clarke & Warwick taxonomic diversity indices. For this, information of three ecoregional salticid diversities was obtained and analyzed between Upper Parana Atlantic Forest (UPAF), Araucaria Moist Forest (AMF), and Southern Cone Mesopotamian Savanna (SCMS). Results showed differences between the three ecoregions of the province, mainly Southern savannas regarding the forests of Northern Misiones. Most species were registered in UPAF followed by AMF, however the α-taxonomic diversity of salticids was higher in SCMS than in UPAF and AMF. The β-taxonomic diversity showed that the proportions of shared species between SCMS and UPAF (or and AMF) were the lowest. The high taxonomic dissimilarity among ecoregions is an indication that the three assemblages are distant, showing a variation in their vegetation habitat and/or bioclimatic characteristics as a possible reason. The need to expand with new samples in subsampled or underexplored areas of Misiones remains essential, however this study contributes to information about biodiversity levels of salticid fauna in three ecoregions of Northeast Argentina, and will provide reference data for future studies for management plans. © 2016, Universidad de Costa Rica. All rights reserved.

Palacios-Gimenez O.M.,Claro | Marti D.A.,National University of Misiones | Cabral-de-Mello D.C.,Claro
Chromosoma | Year: 2015

Sex chromosomes have evolved many times from morphologically identical autosome pairs, most often presenting several recombination suppression events, followed by accumulation of repetitive DNA sequences. In Orthoptera, most species have an X0♂ sex chromosome system. However, in the subfamily Melanoplinae, derived variants of neo-sex chromosomes (neo-XY♂ or neo-X1X2Y♂) emerged several times. Here, we examined the differentiation of neo-sex chromosomes in a Melanoplinae species with a neo-XY♂/XX♀ system, Ronderosia bergi, using several approaches: (i) classical cytogenetic analysis, (ii) mapping via fluorescent in situ hybridization of some selected repetitive DNA sequences and microdissected sex chromosomes, and (iii) immunolocalization of distinct histone modifications. The microdissected sex chromosomes were also used as sources for Polymerase chain reaction (PCR) amplification of RNA-coding multigene families, to study variants related to the sex chromosomes. Our data suggest that the R. bergi neo-Y has become differentiated after its formation by a Robertsonian translocation and inversions, and has accumulated repetitive DNA sequences. Interestingly, the ex autosomes incorporated into the neo-sex chromosomes retain some autosomal post-translational histone modifications, at least in metaphase I, suggesting that the establishment of functional modifications in neo-sex chromosomes is slower than their sequence differentiation. © 2015, Springer-Verlag Berlin Heidelberg.

Zurita G.A.,University of Buenos Aires | Zurita G.A.,National University of Misiones | Bellocq M.I.,University of Buenos Aires
Biotropica | Year: 2012

Traditional approaches to the study of species persistence in fragmented landscapes generally consider a binary classification of habitat being suitable or unsuitable; however, the range of human-modified habitats within a region may offer a gradient of habitat suitability (or conservation value) for species. We identified such a gradient by comparing bird assemblages among contrasting land uses (pine plantations of different age, annual crops, clear cuts and cattle pastures) in the Upper Parana Atlantic forest. Bird assemblages and vegetation structure were characterized in an extensive area of 4400 km 2 in Argentina and Paraguay during the breeding seasons of 2005-2010. Similarity of bird assemblages between anthropogenic habitats and the native forest and the proportion of forest species increased with vegetation vertical structure, while the proportion of open-area species decreased. As a consequence, mature tree plantations were the most suitable habitats for forest species and were mainly used by frugivores and bark insectivores. In contrast, open habitats were the least suitable habitat for forest species and were used primarily by insectivores. Human-created habitats that are structurally complex can be used by a subset of forest species, and may improve functional connectivity and mitigate edge effects. The conservation of large tracks of native forests, however, is critical for the long-term persistence of the entire bird assemblage, especially for native forest dependent species. © 2011 by The Association for Tropical Biology and Conservation.

Cardozo D.,National University of Misiones | Toledo L.F.,University of Campinas
Zootaxa | Year: 2013

Pseudopaludicola riopiedadensis was described by Mercadal de Barrio and Barrio (1994) based on two adult females col-lected by Luiz Dino Vizotto in 1963 from Rio Piedade, São José do Rio Preto, São Paulo, Brazil. This taxon was differ-entiated from P. ternetzi based on a series of qualitative and morphometric characters. Nevertheless, the original description and the type material of P. ternetzi were not considered by Mercadal de Barrio and Barrio, and the morpho-logical variation of P. ternetzi was not documented. This work reviews the sample collected by Vizotto in P. riopiedadensis type locality, evaluates the advertisement calls obtained from such population, the two vouchers assigned to P. riopie-dadensis, and a large data set, including type specimens of P. ternetzi to document the morphological variation along its known distribution. Results indicate that P. riopiedadensis was described on the basis of highly variable characters applied to a small sample and share the unique P. ternetzi autapomorphy, a robust body structure with immaculate belly. The lack of differentiation in both advertisement call and morphology rejects the status of P. riopiedadensis as distinct species, and we therefore suggest to formally consider P. riopiedadensis as junior synonym of P. ternetzi. Copyright © 2013 Magnolia Press.

Ramallo L.A.,National University of Misiones | Mascheroni R.H.,National University of La Plata
Journal of Food Engineering | Year: 2010

Dehydrofreezing technique involves one step of partial dehydration before freezing, in order to diminish the tissue damage by removing part of water from vegetable tissue prior to freezing. The objective of the present study was to evaluate the effect of osmotic dehydration and hot air-drying, applied previous to the freezing process, on the end quality of pineapple slices. Quality loss was quantified through drip loss, ascorbic acid content and mechanical properties changes of tissue. Freezing was carried out in a conventional air-blast tunnel at -31.5 ± 2 °C. Mechanical properties of fresh and dehydrated fruit, with and without the later process of freezing, were evaluated through compression tests. Ascorbic acid content was quantified by liquid chromatography. Osmotic dehydration and hot air-drying have the beneficial effect of reducing the time necessary for pineapple samples freezing. The freezing-thawing process affects the values of pineapple samples mechanical properties. Ascorbic acid losses were somewhat greater during the osmotic dehydration than with air dehydration. © 2010 Elsevier Ltd. All rights reserved.

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