Instituto Tecnologico Vale ITV

Ouro Preto, Brazil

Instituto Tecnologico Vale ITV

Ouro Preto, Brazil
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Valdivia H.O.,Federal University of Minas Gerais | Valdivia H.O.,Us Naval Medical Research Unit No 6 | Oliveira G.,Instituto Tecnologico Vale ITV | Gabaldon T.,Center for Genomic Regulation | And 3 more authors.
BMC Genomics | Year: 2015

Background: Leishmaniasis is a neglected parasitic disease with diverse clinical manifestations and a complex epidemiology. It has been shown that its parasite-related traits vary between species and that they modulate infectivity, pathogenicity, and virulence. However, understanding of the species-specific adaptations responsible for these features and their evolutionary background is limited. To improve our knowledge regarding the parasite biology and adaptation mechanisms of different Leishmania species, we conducted a proteome-wide phylogenomic analysis to gain insights into Leishmania evolution. Results: The analysis of the reconstructed phylomes (totaling 45,918 phylogenies) allowed us to detect genes that are shared in pathogenic Leishmania species, such as calpain-like cysteine peptidases and 3'a2rel-related proteins, or genes that could be associated with visceral or cutaneous development. This analysis also established the phylogenetic relationship of several hypothetical proteins whose roles remain to be characterized. Our findings demonstrated that gene duplication constitutes an important evolutionary force in Leishmania, acting on protein families that mediate host-parasite interactions, such as amastins, GP63 metallopeptidases, cathepsin L-like proteases, and our methods permitted a deeper analysis of their phylogenetic relationships. Conclusions: Our results highlight the importance of proteome wide phylogenetic analyses to detect adaptation and evolutionary processes in different organisms and underscore the need to characterize the role of expanded and species-specific proteins in the context of Leishmania evolution by providing a framework for the phylogenetic relationships of Leishmania proteins. Phylogenomic data are publicly available for use through PhylomeDB ( ). © 2015 Valdivia et al.

Guimaraes J.T.F.,Instituto Tecnologico Vale ITV | Nogueira A.C.R.,Federal University of Pará | Da Silva J.B.C.,Federal University of Pará | Soares J.L.,Federal University of Pará | And 2 more authors.
Ameghiniana | Year: 2015

In order to reassess and amend previously published palynological data drawn from the Novo Remanso Formation, central Amazonia, we revisited the organic-rich samples from their work using systematic and quantitative biostratigraphic analyses, with possible implications in the biodiversity and paleoecological studies of Late Neogene deposits of Amazonia. In the study area, the Novo Remanso Formation is characterized by sandstones and mudstones deposited in a meandering river environment. The palynological assemblage comprises 46 morphotypes, including 21 species of pollen and 25 species of spores. Polypodiisporites usmensis, Retitrescolpites? irregularis and Mauritiidites franciscoi var. franciscoi, typical of lowland freshwater forests and shallow water lakes dominate the assemblage. Also, lower frequencies of Grimsdalea magnaclavata co-occur with Psilatricolporites crassoexinatus, Proteacidites triangulatus, Bombacacidites simpliciriloensis, Pteridaceoisporis gemmatus and Cingulatisporites laevigatus. Based on quantitative biostratigraphic techniques, the Novo Remanso Formation is assigned a middle Miocene-Pliocene age in our study area. The presence of Elaterosporites klaszii (Albian-Cenomanian) in the Novo Remanso deposits strongly indicates Cretaceous rocks in the source-area, whereas absence of Andine palynomorphs may be indicative of a nearby source area for the deposits during the deposition of the Novo Remanso Formation.

Pessoa R.S.,Federal University of Lavras | Silva C.A.,Federal University of Lavras | Moretti B.S.,Federal University of Lavras | Furtini Neto A.E.,Instituto Tecnologico Vale ITV | And 2 more authors.
Ciencia e Agrotecnologia | Year: 2015

Brazil imports most of the potassium that it consumes in agriculture, however, such huge external dependence can be minimized with the use of alternative local K bearing rocks. This experiment was conducted with the objective of evaluating the solubility of nepheline syenite and glauconite as a function of three organic matrices, humic acid, citric acid and coffee husk. Incubation of low grade K rocks and organic matrices were done in laboratory conditions, in a completely randomized design. Each rock was mixed with five different doses of each organic matrix and the potassium solubilized was measured periodically, during 180 days. Regardless of the organic matrix and its dose investigated, nepheline syenite samples released more K than the modified glauconite. Soluble K increased as the incubation time increased and its release was greater as the organic matrix dose increased. There was more soluble K when the coffee husk was mixed with the potassic rocks, in relation to the humic and citric acids. © 2015, Federal University of Lavras. All rights Reserved.

Massola C.P.,São Paulo Institute for Technological Research | Chaves A.P.,Instituto Tecnologico Vale ITV | Albertin E.,São Paulo Institute for Technological Research
Journal of Materials Research and Technology | Year: 2016

Comminution operations are the most expensive and energy consuming in the mineral industry. Any action aiming at reducing the costs associated with that step is welcome, and lowering the consumption of grinding media figures among the main concerns related to decreasing comminution costs. To reach that goal, it is necessary to know and understand the wear mechanisms that take place during the grinding process, as well as to consider the details of such process like the inhomogeneous feed and the interaction between mineral slurry and grinding media. Wet grinding can also add a corrosive component to total wear mechanism, and then wear rates are expected to rise from synergies between corrosive and abrasive components. Though corrosion phenomena are broadly accepted to happen in wet grinding - even when the ball alloy has high chromium content - studies on verifying its importance are scarce. Tests in laboratory mills can simulate most of the conditions present in the industrial mill, despite being inexpensive and much faster than the tests performed with industrial equipment. © 2016 Brazilian Metallurgical, Materials and Mining Association.

Guimaraes J.T.F.,Instituto Tecnologico Vale ITV | Nogueira A.C.R.,Federal University of Pará | Bandeira Cavalcante Da Silva Jr. J.,Federal University of Pará | Lima Soares J.,Federal University of Pará | Silveira R.,Federal University of Amazonas
Journal of Paleontology | Year: 2013

Samples from outcrops of the Miocene Solimões and Barreiras formations from the central and coastal Amazon regions of Brazil were analyzed palynologically. Assemblages of fossil fungi were identified, and are described herein, and their relevance to paleoenvironmental and paleoclimatic studies in tropical regions discussed. The fungal assemblage comprises four spore groups, 19 species belonging to 12 genera. Additionally, two new species are proposed. The samples from the Solimões Formation contain the following taxa: Mediaverrunites elsikii, Mediaverrunites mulleri, Monoporisporites sp., Fusiformisporites crabbii, and Multicellites cingulatus. The presence of these suggests river channel margins colonized by freshwater vegetation, where seasonal fluctuations of water table and rainfall produce wetter substrates. The samples from the Barreiras Formation showed higher species and generic diversity than those from the Solimões Formation with Hypoxylonites minutus, Hypoxylonsporites ater, Hypoxylonites sp., the new species Inapertisporites multiporus n. sp., Pluricellaesporites regularis, Lacrimasporonites levis, Monoporisporites annulatus, Spirotremesporites simplex, Dyadosporites novus, Dyadosporites sp., and Multicellaesporites attenuates. All of these correspond to parasitic fungi from a range of from tropical wetlands. Spegazzinites sp. and Dicellaesporites aculeolatus, good indicators of marine influence and mangrove presence, were also identified in the samples from the Barreiras Formation. Furthermore, the fungal spore taxa Inapertisporites multiporus, Mediaverrunites elsikii, Mediaverrunites mulleri, Pluricellaesporites regularis, and Spirotremesporites simplex serve as stratigraphic indicators when combined with miospore index taxa such as Crassoretitriletes vanraadshooveni, Grimsdalea magnaclavata and Fenestrites longispinosus indicating a Miocene age for these sediments in the Amazon region. Copyright © 2013, The Paleontological Society.

Nogueira A.C.R.,Federal University of Pará | Silveira R.,Federal University of Amazonas | Guimaraes J.T.F.,Instituto Tecnologico Vale ITV
Journal of South American Earth Sciences | Year: 2013

Palynological and stratigraphical analyses were carried out on the outcrops of the Solimões River to present new information about freshwater paleoenvironments of a fluvial-deltaic and meandering river system, evaluate the vegetation changes in the upper Solimões and Içá Formations in the eastern Solimões Basin, and the role of the Purus Arc in the evolution of central Amazon during the upper Neogene. The upper Miocene to Pliocene Solimões Formation is related to a fluvial-deltaic system, with fine-grained sediments of the prodelta-lacustrine environment supplied by meandering distributaries and delta front environment. The lake and distributaries were surrounded by extensive deltaic and floodplains colonized by lowland freshwater forests under wet climate conditions, persisting until the Pliocene. The Içá Formation started to deposit unconformably on the Solimões Formation during the Pleistocene, following the development of extensive meandering channels surrounded by floodplains of an essentially fluvial system linked to development of the present eastward direction of the Amazon River until the Atlantic coast. These floodplains were colonized by few palm species and pteridophytes of lowland freshwater forests during the Pleistocene. Additionally, no algae and fungi were observed, which may be related to drier climate conditions and/or different morphological conditions than the upper Solimões Formation. © 2013 Elsevier Ltd.

Guimaraes J.T.F.,Instituto Tecnologico Vale ITV | Cohen M.C.L.,Federal University of Pará | Franca M.C.,Federal University of Pará | Silva A.K.T.,Federal University of Pará | Rodrigues S.F.S.,Federal University of Pará
Acta Amazonica | Year: 2013

Based on sedimentological and geochemical data, this work relates spectrophotometric measurements with sediment composition and its application in palaeoecological studies of Amazon wetlands. The CIELAB values are directly related to mineralogical and chemical composition, mostly involving quartz, iron oxyhydroxides and sulfides (e.g. pyrite), and total organic carbon. Total organic carbon contents between 0.4-1%, 1-2%, 3-5% and 15-40% were related to L* (lightness) data of 27, 26-15, 7-10 and 7 or less, respectively. The CIELAB values of a deposit in Marabá, Pará, were proportional to variations in quartz and total organic carbon contents, but changes in zones of similar color, mainly in the +a* (red) and +b* (yellow) values of deposits in Calçoene, Amapá and Soure, Pará, indicate a close relationship between total organic carbon content and iron oxyhydroxides and sulfides. Furthermore, the Q7/4 diagram (ratio between the % reflectance value at 700 nm to that at 400 nm, coupled with L*) indicated iron-rich sediments in the bioturbated mud facies of the Amapá deposit, bioturbated mud and bioturbated sand facies of Soure deposit, and cross-laminated sand and massive sand facies of the Marabá core. Also, organic-rich sediments were found in the bioturbated mud facies of the Amapá deposit, lenticular heterolithic and bioturbated mud facies of the Soure deposit, and laminated mud and peat facies of the Marabá deposit. At the Marabá site, the data suggest an autochthonous influence with peat formation. The coastal wetland sites at Marajó and Amapá represent the development of a typical tidal flat setting with sulfide and iron oxyhydroxides formation during alternated flooding and drying.

dos Santos A.P.P.,National Institute for Space Research | de Souza J.R.S.,Federal University of Pará | de Souza E.B.,Federal University of Pará | de Souza E.B.,Instituto Tecnologico Vale ITV | And 2 more authors.
Revista Brasileira de Meteorologia | Year: 2014

Operational records of power outages of the electric energy distribution systems in eastern Amazonia presented a large number of events attributed to lightning strikes, during the 2006 to 2009 period. The regional electricity concessionary data were compared to actual lightning observations made by SIPAM’s LDN system, over two areas where operational sub systems of transmission lines are installed. Statistical relations were drawn between the monthly lightning occurrence density and the number of power outages of the electric systems for both areas studied. The results showed that, although with some delays between these variables peaks, the number of power disruptions has a tendency to follow the behavior of the lightning occurrence densities variations. The numerical correlations were positive and may be useful to the transmission lines maintenance crews at least for the Belém-Castanhal electricity distribution sub system. Evidence was found, that the SST’s over certain areas of the Pacific and Atlantic Oceans, influence convection over the area of interest, and may help to prognosticate the periods of intense electric storms, requiring repair readiness for the regional electric systems. © 2014, Sociedade Brasileira de Meteorologia. All rights reserved.

De Moraes B.C.,Instituto Tecnologico Vale ITV | De Souza E.B.,Instituto Tecnologico Vale ITV | De Souza E.B.,Federal University of Pará | Ribeiro J.B.M.,Federal University of Pará | And 2 more authors.
Revista Brasileira de Meteorologia | Year: 2014

Human activities that alter the greenhouse gases concentrations will have a direct influence on plant health issues. In order to minimize both the production loss and the quality, and to guide the choice of adaptation strategies and management, further studies to investigate the impacts of climate change on agriculture - in the spatial and temporal scales - and their pathogens are needed. The main goal of this work was to explore the global climate impact on the ecoclimatology of the citrus blackfly (Aleurocanthus woglumi Ashby) in State of Pará. To do so, the thermal requirements of Aleurocanthus woglumi Ashby developed in laboratory and on the ecoclimatological zoning based on the annual insect population was first analyzed using air temperature data series from 15 meteorological stations. Then, the populational increase of the studied insect through the projections of global climate model CCSM 3.0, between years 2030 and 2090, was simulated and analyzed. The results of simulations suggest that the number of generations of the insect will increase 50% in Pará state.

Magalhaes D.M.,Instituto Agronomico | Magalhaes D.M.,University of Campinas | Scholte L.L.S.,Instituto Nacional Of Ciencia E Tecnologia Em Doencas Tropicais | Silva N.V.,Instituto Agronomico | And 5 more authors.
BMC Genomics | Year: 2016

Background: Leucine-rich repeat receptor-like kinases (LRR-RLKs) represent the largest subfamily of plant RLKs. The functions of most LRR-RLKs have remained undiscovered, and a few that have been experimentally characterized have been shown to have important roles in growth and development as well as in defense responses. Although RLK subfamilies have been previously studied in many plants, no comprehensive study has been performed on this gene family in Citrus species, which have high economic importance and are frequent targets for emerging pathogens. In this study, we performed in silico analysis to identify and classify LRR-RLK homologues in the predicted proteomes of Citrus clementina (clementine) and Citrus sinensis (sweet orange). In addition, we used large-scale phylogenetic approaches to elucidate the evolutionary relationships of the LRR-RLKs and further narrowed the analysis to the LRR-XII group, which contains several previously described cell surface immune receptors. Results: We built integrative protein signature databases for Citrus clementina and Citrus sinensis using all predicted protein sequences obtained from whole genomes. A total of 300 and 297 proteins were identified as LRR-RLKs in C. clementina and C. sinensis, respectively. Maximum-likelihood phylogenetic trees were estimated using Arabidopsis LRR-RLK as a template and they allowed us to classify Citrus LRR-RLKs into 16 groups. The LRR-XII group showed a remarkable expansion, containing approximately 150 paralogs encoded in each Citrus genome. Phylogenetic analysis also demonstrated the existence of two distinct LRR-XII clades, each one constituted mainly by RD and non-RD kinases. We identified 68 orthologous pairs from the C. clementina and C. sinensis LRR-XII genes. In addition, among the paralogs, we identified a subset of 78 and 62 clustered genes probably derived from tandem duplication events in the genomes of C. clementina and C. sinensis, respectively. Conclusions: This work provided the first comprehensive evolutionary analysis of the LRR-RLKs in Citrus. A large expansion of LRR-XII in Citrus genomes suggests that it might play a key role in adaptive responses in host-pathogen co-evolution, related to the perennial life cycle and domestication of the citrus crop species. © 2016 The Author(s).

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