31 resultados para state of Minas Gerais press and journalism
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)
Resumo:
In this article we describe and illustrate the new species Paepalanthus hirtellus (Eriocaulaceae, Paepalanthoideae). The species is, as far as known, restricted to Pico do Itambe State Park, in the state of Minas Gerais, Brazil. Paepalanthus hirtellus occurs on the campos rupestres of the Espinhaco Range. We compare it with P. lombensis and P. chrysophorus, the two morphologically most similar species. We provide additional comments on the morphological variability, habitat, geographic distribution and we provide its conservation status.
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A new species of Vriesea Lindl. belonging to section Xiphion (E. Morren) E. Morren ex Mez. - V. sanfranciscana Versieux & Wand.- is described and illustrated. The species is only known to occur in the Serra da Canastra National Park, located in the southwestern Minas Gerais, Brazil, and is morphologically related to V. atropurpurea Silveira from serra do Cipo, Espinhaco range.
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We describe and illustrate two new species, Actinocephalus delicatus and A. giuliettiae (Eriocaulaceae, Paepalanthoideae), from the Espinhaco Range in Minas Gerais, Brazil, and compare them with the morphologically most similar species. Diagnostic characters, morphological variation, geographic distribution, habitat and conservation status, as well as line drawings, photos and a distribution map are provided for both species.
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Phylogenetic relationships and divergence times for 10 populations of the three recognized ""species"" of Brazilian lizards of genus Eurolophosaurus were estimated from 1229 bp of cyt b, COI, 12S, and 16S rRNA mitochondrial gene segments. Eurolophosaurus is monophyletic and the basal split within the genus separates E divaricatus from a clade comprising E amathites and E nanuzae. Three populations of E divaricatus, which occurs along the western bank of Rio S (a) over tildeo Francisco, were consistently grouped together. Oil the east bank of the river, E amathites and E nanuzae from state of Bahia were recovered as the sister group of E nanuzae populations from state of Minas Gerais. The paraphyly of E nanuzae and the high divergence levels among populations of E divaricatus strongly suggest that species limits in Eurolophosaurus should be revised. Even considering an extreme evolutionary rate of 2.8% sequence divergence per million years for the four gene segments analyzed together, E. divaricatus would have separated from the two other species by at least 5.5 my ago, and E. amathites from E nanuzae populations from Bahia and Minas Gerais, respectively, by 1.5 and 3.5 my. The paleolacustrine hypothesis and changes in the course of the river potentially explain faunal divergence in the area, but divergences are much older than previously admitted. (C) 2007 Elsevier Inc. All rights reserved.
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In this work the effect of doping concentration and depth profile of Cu atoms on the photocatalytic and surface properties of TiO(2) films were studied. TiO(2) films of about 200 nn thickness were deposited on glass substrates on which a thin Cu layer (5 nm) was deposited. The films were annealed during 1 s to 100 degrees C and 400 degrees C, followed by chemical etching of the Cu film. The grazing incidence X-ray fluorescence measurements showed a thermal induced migration of Cu atoms to depths between 7 and 31 nm. The X-ray photoelectron spectroscopy analysis detected the presence of TiO(2), Cu(2)O and Cu(0) phases and an increasing Cu content with the annealing temperature. The change of the surface properties was monitored by the increasing red-shift and absorption of the ultraviolet-visible spectra. Contact angle measurements revealed the formation of a highly hydrophilic surface for the film having a medium Cu concentration. For this sample photocatalytic assays, performed by methylene blue discoloration, show the highest activity. The proposed mechanism of the catalytic effect, taking place on Ti/Cu sites, is supported by results obtained by theoretical calculations. (C) 2010 Elsevier B.V. All rights reserved.
Resumo:
Objectives. To describe the prevalence of dental caries in children with deciduous teeth in urban and rural areas in the state of Sao Paulo, Brazil, and to identify associated factors. Methods. The study included 24 744 children ( 5 - 7 years of age) examined as part of an epidemiological survey on oral health carried out in the state of Sao Paulo ( Levan-tamento Epidemiologico de Sa de Bucal do Estado de Sao Paulo). Multilevel analysis was used to investigate whether the prevalence of untreated caries was associated with the sociodemographic characteristics of the children examined or with the socioeconomic aspects of the participating cities. Results. Being black or brown ( adjusted odds ratio ( OR) = 1.27), attending school in rural areas ( adjusted OR = 1.88), and attending public school ( adjusted OR = 3.41) were identified as determinants for an increased probability of presenting deciduous teeth with untreated caries. Being a female ( adjusted OR = 0.83) was identified as a protective factor. The negative coefficients obtained for second- level independent variables indicate that the oral health profile of the cities included in the study were positively impacted by a higher municipal human development index ( beta = - 0.47) and fluoridated drinking water ( beta = - 0.32). Conclusions. The prevalence of untreated caries is influenced by individual and sociodemographic factors. The present study provides epidemiological information concerning the rural areas in the state of Sao Paulo. This information is useful for strategic planning and for establishing guidelines for oral health actions in local health systems, thereby contributing to oral health equity.
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A field survey of resistance was conducted based on the larval packet test technique with synthetic pyrethroids (cypermethrin and deltamethrin) and organophosphates (chlorpyriphos) in Rhipicephalus (Boophilus) microplus field populations from six different regions of the State of Sao Paulo (Brazil). 82.6% of the populations showed resistance to cypermethrin, 86.36% to deltamethrin and 65.25% to chlorpyriphos, with 50% presenting resistance to both SP and OP acaricide. According to the questionnaires completed by the producers, OP + SP mixtures followed by SP-only formulations were the products most commonly used for controlling the cattle tick in the surveyed areas. The present study showed high occurrence of resistance to SP and OP in the State of Sao Paulo, Brazil and revealed the type of strategy adopted by small dairy farms in this state. This information is fundamental in order to establish the monitoring of resistance on each farm individually, contributing to the rational use of acaricides for the control of R. (B.) microplus. (C) 2011 Elsevier B.V. All rights reserved.
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Although literature presents several alternatives, an approach based on the electronic analogy was still not considered for the implementation of an inductor-free realization of the double scroll Chua`s circuit. This paper presents a new inductor-free configuration of the Chua`s circuit based on the electronic analogy. This proposal results in a versatile and functional inductorless implementation of the Chua`s circuit that offers new and interesting features for several applications. The analogous circuit is implemented and used to perform an experimental mapping of a large variety of attractors.
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A checklist of the 14 genera and 34 species of Bromeliaceae from the Parque Estadual do Rio Preto in Sao Goncalo do Rio Preto municipality, Minas Gerais state, southeastern Brazil, is presented. The Tillandsioideae was the most diverse subfamily and was found to be concentrated in rocky field areas. Bromelioideae is also a species rich subfamily, but its taxa have shown a preference to forested areas and savannas at lower altitudes. Pitcairnioideae is highlighted by its level of endemism, but has only four species. Cryptanthus micrus, a new species found in this area is described and illustrated. Our cluster analysis indicated that the Rio Preto State Park has a Bromeliaceae flora more similar to that from Pico do Itambe and Grao Mogol State Parks. Taxa like Dyckia glandulosa, Orthophytum itambense and Vriesea medusa, which were previously considered to be endemic to Pico do Itambe, now have their area of occurrence extended to Rio Preto. These new occurrences highlight the importance to create a corridor joining these neighboring reserves to connect populations of narrowly ranged or rare species. In this work we present pictures of 19 species in their habitats within the park, and we hope that these illustrations will help in the identification and conservation of these taxa.
Resumo:
On December 9, 2007, a 4.9 m(b) earthquake occurred in the middle of the Sao Francisco Craton, in a region with no known previous activity larger than 4 m(b). This event reached intensity VII MM (Modified Mercalli) causing the first fatal victim in Brazil. The activity had started in May 25, 2007 with a 3.5 magnitude event and continued for several months, motivating the deployment of a local 6-station network. A three week seismic quiescence was observed before the mainshock. Initial absolute hypocenters were calculated with best fitting velocity models and then relative locations were determined with hypoDD. The aftershock distribution indicates a 3 km long rupture for the mainshock. The fault plane solution, based on P-wave polarities and hypocentral trend, indicates a reverse faulting mechanism on a N30 degrees E striking plane dipping about 40 degrees to the SE. The rupture depth extends from about 0.3 to 1.2 km only. Despite the shallow depth of the mainshock, no surface feature could be correlated with the fault plane. Aeromagnetic data in the epicentral area show short-wavelength lineaments trending NNE-SSW to NE-SW which we interpret as faults and fractures in the craton basement beneath the surface limestone layer. We propose that the Caraibas-Itacarambi seismicity is probably associated with reactivation of these basement fractures and faults under the present E-W compressional stress field in this region of the South American Plate. (c) 2009 Elsevier B.V. All rights reserved.
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The occurrences of imperial topaz in the Antonio Pereira mine, Ouro Preto, Minas Gerais, are associated with the metamorphic carbonate rocks of the Minas Supergroup. The crystals have densities varying from 3.46 to 3.58. The parameters of the unitary cells obtained were: 4.658 to 4.663 angstrom (ao), 8.823 to 8.832 angstrom (b(o)), 8.382 to 8.389 angstrom (c(o)), and 344.65 to 345.46 angstrom 3 (V). The refraction indices presented the following variations: 1.622 to 1.630 (nX), 1.624 to 1.632 (nY), 1.633 to 1.640 (nZ), and 0.008 to 0.011 (B). These properties are coherent with the low fluorine contents obtained (16,48%/17,05wt%). Infrared spectroscopy and microthermometry showed that the fluid inclusions, which represent the mineralizing fluids, are formed by H(2)O (with Ca(2+), Mg(2+) and Na(+)), and CO(2) +/- CH(4). The minimal trapping T-P conditions of 290/320 degrees C and 2,349/2,497bar were obtained for the primary fluid inclusions. The pseudo-secondary fluid inclusions were trapped at conditions of lower temperatures and variable pressures, during the deformation process under local alternating states of stress. The microthermometric studies, the structural analysis and the fluorine contents suggest that the mineralized veins were formed from hydrothermal fluids originated during the Brasiliano tectono-metamorphic event.
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Triatoma arthurneivai Lent & Martins and Triatoma wygodzinskyi Lent (Hemiptera: Reduviidae) are two Brazilian species found in the sylvatic environment. Several authors may have misidentified T. arthurneivai and consequently published erroneous information. This work reports the use of geometric morphometric analysis on wings in order to differentiate T. arthurneivai and T. wygodzinskyi, and thus to detect possible misidentifications. Triatomines collected from the field in the states of Minas Gerais and Sao Paulo, and from laboratory colonies, were used. Analyses show a clear differentiation between specimens of T. arthurneivai and T. wygodzinskyi. This indicates that T. arthurneivai populations from Sao Paulo state were misidentified and should be considered as T. wygodzinskyi. This study also suggests that T. arthurneivai is an endemic species from Serra do Cipo, Minas Gerais state.
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Minasia ramosa, a new species from Brazil, is here described and illustrated. The species is endemic to the campos rupestres of the Serra do Cabral, a western extension of the Espinhaco Range in Minas Gerais. Minasia ramosa is characterized by its narrow ensiform leaves, paniculate inflorescence and totally setuliferous cypselae. The affinities of this species are discussed.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The solvatochromism and other spectroscopic and photophysical characteristics of four azo disperse dyes, derived from 2-amino-5-nitrothiazole, were evaluated and interpreted with the aid of experimental data and quantum mechanical calculations. For the non-substituted compound two conformers, E and Z, were proposed for the isolated molecules, being the second one considerably less stable. The optimization of these structures in combination with a SCRF methodology (IEFPCM, Simulating the molecules in a continuum dielectric with characteristics of methanol), suggests that the Z form is not stable in solution. This same behaviour is expected for the substituted compounds, which is corroborated by experimental data presented in previous investigations [A.E.H. Machado, L.M. Rodrigues, S. Gupta, A.M.F. Oliveira-Campos, A.M.S. Silva, J. Mol. Struct. 738 (2005) 239-245]. For the substituted compounds, two forms derived from E conformer (A and R) are possible. Quantum mechanical data suggest for the isolated molecules, that the low energy absorption hand of the E conformers involve at least two close electronic states. having the low-lying excited state a (1)(n,pi*) nature, and being the S-2 state attributed to a (1)(pi,pi*) transition. The data also suggest a small energy gap between the absorption peaks of A and B, related to the easy conversion between these forms. For the structures optimized in combination with the applied SCRF methodology, an states inversion is observed for the Substituted compounds, with a considerable diminish of the energy gap between A and B absorption peaks. The electronic spectra of these compounds are quite sensitive to changes in the solvent polarity. The positive solvatochromism is more evident in aprotic solvents, probably due to the polarization induced by the solute. These compounds do not fluoresce at 298 K, but present a small but perceptible fluorescence at 77 K, which seems to be favoured by the nature of the group in the 2 `-position of the phenyl ring. Moreover, such compounds present expressive values for first hyperpolarizability, which implies in good non-linear optics (NLO) responses and photoswitching capability. (C) 2008 Elsevier B.V. All rights reserved.