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| Registros recuperados: 2.719 | |
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| LIXA,CAROLINA; MUJO,AMANDA; ANOBOM,CRISTIANE D.; PINHEIRO,ANDERSON S.. |
| Bacteria are able to synchronize the population behavior in order to regulate gene expression through a cell-to-cell communication mechanism called quorum sensing. This phenomenon involves the production, detection and the response to extracellular signaling molecules named autoinducers, which directly or indirectly regulate gene expression in a cell density-dependent manner. Quorum sensing may control a wide range of biological processes in bacteria, such as bioluminescence, virulence factor production, biofilm formation and antibiotic resistance. The autoinducers are recognized by specific receptors that can either be membrane-bound histidine kinase receptors, which work by activating cognate cytoplasmic response regulators, or cytoplasmic receptors... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Autoinducer; Bacteria; Quorum sensing; Receptor; Structure. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000502189 |
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| PARANHOS FILHO,ANTONIO C.; NUMMER,ALEXIS R.; ALBREZ,EDILCE A.; RIBEIRO,ALISSON A.; MACHADO,RÔMULO. |
| This paper presents a study of the structural lineaments of the Pantanal extracted visually from satellite images (CBERS-2B satellite, Wide Field Imager sensor, a free image available in INTERNET) and a comparison with the structural lineaments of Precambrian and Paleozoic rocks surrounding the Cenozoic Pantanal Basin. Using a free software for satellite image analysis, the photointerpretation showed that the NS, NE and NW directions observed on the Pantanal satellite images are the same recorded in the older rocks surrounding the basin, suggesting reactivation of these basement structural directions during the Quaternary. So the Pantanal Basin has an active tectonics and its evolution seems to be linked to changes that occurred during the Andean subduction. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Free remote sensing software; Free satellite images; Structural geology; Lineaments; Photointerpretation; Pantanal. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652013000300913 |
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| García-Fuentes,Antonio; Torres-Cordero,Juan A.; Ruiz-Valenzuela,Luis; Lendínez-Barriga,María Lucía; Quesada-Rincón,Juan; Valle-Tendero,Francisco; Veloz,Alberto; León,Yolanda M.; Salazar-Mendías,Carlos. |
| This paper is a floristic and phytosociological study of the dry forest communities of the Dominican Republic. A total of 69 relevés in dry forest biotopes were carried out. The samples were subsequently subjected to Detrended Correspondence Analysis for the determination and study of possible groupings. The study does not cover tree formations growing on serpentines, nor the so-called semideciduous forests, peculiar to areas with higher rainfall. A total of nine phytocoenoses were identified. The most significant results led to the description of six new phytosociological associations: Simaroubetum berteroani(thorny dry forest on coastal dunes), Phyllostylo rhamnoidis-Prosopidetum juliflorae (southern Dominican disturbed dry forest), Consoleo... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Caribbean; Endemism; Multivariate analysis; Phytosociology; Xericity. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000100249 |
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| Abreu,Heber S.; Latorraca,João V.F.; Pereira,Regina P.W.; Monteiro,Maria Beatriz O.; Abreu,Fábio A.; Amparado,Kelysson F.. |
| In spite of the great importance of cellulose the lignin is considered the second most abundant substance of the wood. However, little attention has been given it, mainly to wood properties. The lignin as well as other structural compounds (cellulose and hemicelluloses), has obviously an important role on the wood properties, probably due its composition and existent bonds. In general lignins have β-O-4 (Alkyl Aril Ether) as majoritary bond. This bond in a continued structure form big molecules with spiral conformation as virtual model. Based on this idea, lignins that have high/low β-O-4 content may have differentiated spiraled structures,suggesting different behaviors on the wood properties,which shows that the lignins (Guaicyl:Syringyl (GS)) of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Lignin; Molecular conformation; Wood properties; Structure. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652009000100014 |
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| BAKOUCH,HASSAN S. |
| Abstract A new discrete distribution is introduced. The distribution involves the negative binomial and size biased negative binomial distributions as sub-models among others and it is a weighted version of the two parameter discrete Lindley distribution. The distribution has various interesting properties, such as bathtub shape hazard function along with increasing/decreasing hazard rate, positive skewness, symmetric behavior, and over- and under-dispersion. Moreover, it is self decomposable and infinitely divisible, which makes the proposed distribution well suited for count data modeling. Other properties are investigated, including probability generating function, ordinary moments, factorial moments, negative moments and characterization. Estimation of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Characterization; Discrete distributions; Estimation; Vuong test statistic; Mixture distributions; Thunderstorms data. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652018000602617 |
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| BRITO,ROSÂNGELA; SPECHT,ALEXANDRE; A. FILHO,WILSON S.; FRONZA,EDEGAR; MIELKE,CARLOS G.C.. |
| The representatives of the genus Hylesia Hübner, [1820] are significant among the medically important Lepidoptera. Adult females use abdominal setae to wrap and protect the eggs that remain for months in nature. These setae, in contact with human skin, may cause allergic reactions including swelling, itching and local erythema, known as lepidopterism. The morphology of the abdominal scales and setae from the female H. oratex Dyar, 1913 is herein described and aspects related to their medical significance are discussed. Portions of each abdominal segment were examined through a scanning electron microscope. Two types of scales without medical importance, and two types of setae with medical importance, classified as "true setae" and "modified setae" were... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allergic outbreaks; Lepidopterism; Morphology; Urticating moths. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652015000401763 |
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| Rainho,Claudia R. de; Kaezer,Andréa; Aiub,Claudia A.F.; Felzenszwalb,Israel. |
| N-nitroso compounds, such as N-nitrosodiethylamine (NDEA), can be formed by the reaction of secundary amines with nitrosating agents, and are suspected to be involved in tumors in humans. NDEA has been considered a weak carcinogen in genotoxic assays probably due to the inefficient nitrosamine activation system that is used and/or to the efficient repair system. In this work, we evaluated the sensibility of Allium cepa L. root tips and Tradescantia stamen hair mutation assay (Trad-SH) using Tradescantia pallida var. purpurea for NDEA (0.1; 0.5; 5 and 25mM) genotoxicity and mutagenicity induction. Allium cepa L. was treated with different NDEA concentrations for 3h, for 3 consecutive days, including negative control (distilled water) and positive control... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allium cepa; Genotoxicity; Mutagenicity; N-nitrosodiethylaine; Tradescantia pallida var. purpurea. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652010000400015 |
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| Melo Júnior,Mauro de; Schwamborn,Ralf; Neumann-Leitão,Sigrid; Paranaguá,Maryse N.. |
| The influence of tidal and diel changes on the exchange of Petrolisthes armatus planktonic larvae was studied at the Catuama inlet, which represents an intermediate system of marine and estuarine environments in the Northeast Brazil. To characterize the larval abundance and vertical distribution, samplings were carried out in August 2001 at neap tide and 3 stations, with 3 hours interval over 24 hours. Samples were taken at three or two depths at each station, with a plankton pump coupled to a 300 µm mesh size net. Petrolisthes armatus zoea I and II showed a mean of 26.3 ± 83.6 and 12 ± 38.8 ind m-3, respectively. During flood tides, the larvae were more concentrated in the midwater and surface, which avoided the transport to internal regions. In contrast,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Northeast Brazil; Decapod larvae; Petrolisthes armatus; Estuarine inlet; Transport; Zooplankton. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652012000100009 |
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| BREVES,ANDRÉ; SZÉCHY,MARIA TERESA M. DE; LAVRADO,HELENA P.; JUNQUEIRA,ANDREA O.R.. |
| ABSTRACT The reef-building vermetid Petaloconchus varians occurs in the western Atlantic Ocean, from the Caribbean Sea to the southern coast of Brazil. The present study evaluated the abundance of P. varians on intertidal rocky shores in Ilha Grande Bay (Rio de Janeiro State), and characterized their reefs, describing the species density, besides the weight and the belt width of the reefs. Petaloconchus varians reefs were recorded at 25 sites, with rocky shores exposed to different wave action (very sheltered, sheltered, semi-exposed and exposed) and slopes (10° to 46°). Clusters of individuals constructed large reefs along the middle intertidal zone, creating a wide belt (38 cm to 2 m). The density of P. varians and the weight of the reefs ranged from 620... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Abundance; Molluscs; Rio de Janeiro; Southwestern Atlantic Ocean; Wave exposure. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652017000300907 |
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| LOZANO,FEDERICO; RODRIGUES,MARCIEL E. |
| Abstract Acanthagrion marinae sp. nov. (Holotype male: BRASIL, Mato Grosso do Sul, Campo Grande, UFMS, 20°29’56.26’’S - 54°36’48.43’’W, 547m, leg. M.E. Rodrigues, 03.ii.2015, collection code: VZYG437, MLP) is described and illustrated on the basis of 15 males. The new species belongs to the apicale species group by having horns on S10 and sclerotized hooks on tip of distal segment of the genital ligula. It can be easily distinguished from other species of the group by a combination of characters of the genital ligulae (presence of setae on segment two; absence of setae at flexure; distal lateral lobes of segment three absent). Notes on habitat and a modification of previous keys for the species of the apicale group are provided. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Acanthagrion; Coenagrionidae; Neotropics; Odonata; Zygoptera. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652018000602865 |
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| Registros recuperados: 2.719 | |
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