1000 resultados para West Tisbury


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Objective: To estimate factors associated with condom use at last sexual intercourse among adolescents.Methods: Cross-sectional study of a representative sample of 368 sexually active adolescents aged 13-17 years from eight public high schools on Santiago Island, Cape Verde, 2007. The level of significance was 5.0% obtained from logistic regression, considering the association between condom use and socio-demographic, sexual and reproductive variables.Results: The prevalence of condom use at last sexual intercourse was 94.9%. Factors associated with condom use at last sexual relationship were: non-Catholic religion (OR=0.68, 95%CI: 0.52; 0.88) and affective-sexual partnership before the interview (OR=5.15, 95%CI: 1.79; 14.80).Conclusions: There was a high prevalence of condom use at last sexual intercourse of adolescents.

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Eight taxa of marine invertebrates, including two new bivalve species, are described from the Low Head Member of the Polonez Cove Formation (latest early Oligocene) cropping out in the Vaureal Peak area, King George Island, West Antarctica. The fossil assemblage includes representatives of Brachiopoda (genera Neothyris sp. and Liothyrella sp.), Bivalvia (Adamussium auristriatum sp. nov., ?Adamussium cf. A. alanbeui Jonkers, and Limatula (Antarctolima) ferraziana sp. nov.), Bryozoa, Polychaeta (serpulid tubes) and Echinodermata. Specimens occur in debris flows deposits of the Low Head Member, as part of a fan delta setting in a high energy, shallow marine environment. Liothyrella sp., Adamussium auristriatum sp. nov. and Limatula ferraziana sp. nov. are among the oldest records for these genera in King George Island. In spite of their restrict number and diversification, bivalves and brachiopods from this study display an overall dispersal pattern that roughly fits in the clockwise circulation of marine currents around Antarctica accomplished in two steps. The first followed the opening of the Tasmanian Gateway at the Eocene/Oligocene boundary, along the eastern margin of Antarctica, and the second took place in post-Palaeogene time, following the Drake Passage opening between Antarctic Peninsula and South America, along the western margin of Antarctica.

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The immunological status of five children with West syndrome consequent to previous cerebral lesions was investigated. Three children had West syndrome and two were in transition from West to Lennox-Gastaut syndrome. All of them showed cellular immunological deficiencies in the following tests: sensitization to DNCB, intracutaneous reaction to PHA, inhibition of leukocyte migration, blastic transformation of lymphocytes, T and B lymphocytes in peripheral blood and levels of serum immunoglobulins. These immunological deficiencies, of different degrees of severity, were associated with frequent infections in these children. A possible association between the immunological deficiencies and autoimmunity is discussed.

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Recent field investigations and geochronological studies of Neoproterozoic rocks in the northwestern part of the Borborema Province, Ceará State, NE Brazil provide important clues pertaining to the nature of convergence between the Borborema Province and the West African-São Luis craton during the assembly of West Gondwana. U-Pb zircon data indicate that the earliest evidence of convergent magmatism along the northwest margin of the Borborema Province occurred around 777 Ma, and was followed by the development of a large continental arc batholith (Santa Quitéria batholith) between ca. 665 and 591 Ma within the central part of Ceará State. These findings, along with supporting geophysical data, suggest that convergence between the Borborema Province and the West African-São Luis craton involved closure of an oceanic realm with subduction polarity to the southeast beneath the northwestern part of the province. Consequently, it seems likely that the Pharusian Ocean was continuous from the Hoggar Province in West Africa into South America during the late Neoproterozoic and additional data suggests that it may have even been connected with the Goianides Ocean of the Brasília Belt farther to the southwest.

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With the development of greenhouse grown crops, the whitefly Trialeurodes vaporariorum (West.) has become an important pest. Aiming at verifying the effect of host on the development of this species, the biology of the whitefly was studied on bean (Phaseolus vulgaris L.) cultivars IAC-Carioca Pyatã, IAPAR-57, Jalo Precoce, IAC-Bico de Ouro, IAC-Maravilha and on soybean (Glycine max L.) cultivar Cristalina. The study was conducted at the Laboratório de Entomologia Agrícola - FCA-UNESP, at 25 ± 3°C temperature, 80 ± 10% RH and 14h photophase. The biological parameters assessed were duration, viability and number of nymphal instars; male and female longevity, oviposition period, number of eggs per female and sex ratio; egg viability and incubation period and the life cycle duration. Based on data obtained, fertility life tables were constructed to allow a comparative analysis of the effect of cultivars on the biological development and consequent population growth of this species. The bean cultivars IAC-Maravilha and Jalo Precoce negatively influenced T. vaporariorum development, whereas, the other bean cultivars studied, as well as the soybean cultivar Cristalina, provided good conditions for development of this pest.

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The Brasília belt borders the western margin of the São Francisco Craton and records the history of ocean opening and closing related to the formation of West Gondwana. This study reports new U-Pb data from the southern sector of the belt in order to provide temporal limits for the deposition and ages of provenance of sediments accumulated in passive margin successions around the south and southwestern margins of the São Francisco Craton, and date the orogenic events leading to the amalgamation of West Gondwana. Ages of detrital zircons (by ID-TIMS and LA-MC-ICPMS) were obtained from metasedimentary units of the passive margin of the São Francisco Craton from the main tectonic domains of the belt: the internal allochthons (Araxá Group in the Áraxá and Passos Nappes), the external allochthons (Canastra Group, Serra da Boa Esperança Metasedimentary Sequence and Andrelândia Group) and the autochthonous or Cratonic Domain (Andrelândia Group). The patterns of provenance ages for these units are uniform and are characterised as follows: Archean- Paleoproterozoic ages (3.4-3.3, 3.1-2.7, and 2.5-2.4Ga); Paleoproterozoic ages attributed to the Transamazonian event (2.3-1.9Ga, with a peak at ca. 2.15Ga) and to the ca. 1.75Ga Espinhaço rifting of the São Francisco Craton; ages between 1.6 and 1.2Ga, with a peak at 1.3Ga, revealing an unexpected variety of Mesoproterozoic sources, still undetected in the São Francisco Craton; and ages between 0.9 and 1.0Ga related to the rifting event that led to the individualisation of the São Francisco paleo-continent and formation of its passive margins. An amphibolite intercalation in the Araxá Group yields a rutile age of ca. 0.9Ga and documents the occurrence of mafic magmatism coeval with sedimentation in the marginal basin. Detrital zircons from the autochthonous and parautochthonous Andrelândia Group, deposited on the southern margin of the São Francisco Craton, yielded a provenance pattern similar to that of the allochthonous units. This result implies that 1.6-1.2Ga source rocks must be present in the São Francisco Craton. They could be located either in the cratonic area, which is mostly covered by the Neoproterozoic epicontinental deposits of the Bambuí Group, or in the outer paleo-continental margin, buried under the allochthonous units of the Brasília belt. Crustal melting and generation of syntectonic crustal granites and migmatisation at ca. 630Ma mark the orogenic event that started with westward subduction of the São Francisco plate and ended with continental collision against the Paraná block (and Goiás terrane). Continuing collision led to the exhumation and cooling of the Araxá and Passos metamorphic nappes, as indicated by monazite ages of ca. 605Ma and mark the final stages of tectonometamorphic activity in the southern Brasília belt. Whilst continent-continent collision was proceeding on the western margin of the São Francisco Craton along the southern Brasília belt, eastward subduction in the East was generating the 634-599Ma Rio Negro magmatic arc which collided with the eastern São Francisco margin at 595-560Ma, much later than in the Brasília belt. Thus, the tectonic effects of the Ribeira belt reached the southernmost sector of the Brasília belt creating a zone of superposition. The thermal front of this event affected the proximal Andrelândia Group at ca. 588Ma, as indicated by monazite age. The participation of the Amazonian craton in the assembly of western Gondwana occurred at 545-500Ma in the Paraguay belt and ca. 500Ma in the Araguaia belt. This, together with the results presented in this work lead to the conclusion that the collision between the Paraná block and Goiás terrane with the São Francisco Craton along the Brasília belt preceded the accretion of the Amazonian craton by 50-100 million years. © 2003 Elsevier B.V. All rights reserved.

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A pioneer GPR - Ground Penetrating Radar - survey was carried out in the Pantanal of Mato Grosso State, westcentral region of Brazil. Fieldwork acquisitions were carried out in February/2001 and August/2002 in order to understand avulsion processes that are occurring within the Taquari alluvial megafan. The main subjects were to map channel, crevasses and floodplain morphology, as well as active sedimentary bedforms. Many GPR profiles were surveyed in the medium and lower Taquari River course. Subaqueous megaripples and exposed sand bars inside the Taquari channel were identified in the medium fan area. Similar features were observed in the lower fan channels, where there are also many crevasses in the marginal levees. During the flooding seasons the flow splays out in the floodplain where new distributary channels are being formed. As shown by GPR data, in the lower fan the Taquari channel is topographically higher than the adjacent floodplain, situation in which avulsion is a natural process of river course shifting. The lack of information about river morphology and dynamics is a major strain to better understand the sediment transport and the avulsion processes in the Taquari megafan. In this context, the GPR data obtained in wet and dry seasons, integrated to sedimentological information, have been very important to characterize the fluvial dynamics and the avulsion phenomena.

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A novel and timely ground penetrating radar (GPR) survey has been carried out in Pantanal from Mato Grosso State, west-central Brazil. Fieldwork was carried out on February/2001 and August/2002 in an attempt to understand avulsion processes that are occurring within Taquari alluvial megafan. The main objectives were to map channel, crevasse and floodplain morphology, as well as active sedimentary bedforms. Many GPR profiles were acquired in the medium and lower Taquari River course. Subaqueous megaripples and exposed sand bars were identified in the medium fan area. Similar features were observed in the lower fan channels, where there were many crevasses in the marginal levees. During the flooding seasons, the flow splays out on to the floodplain, where new distributary channels are being formed. GPR data show that the lower fan, Taquari channel is topographically higher than the adjacent floodplain, thus favoring avulsion as a natural process of river course shifting. GPR data obtained during the wet and dry seasons, together with sedimentology information have been very important in characterizing the fluvial dynamics, and avulsion phenomena. © 2005 Springer Science+Business Media, Inc.

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A study on the presence of herbicides, namely simazine, metribuzin, metolachlor, trifluralin, atrazine and two metabolites, deisopropylatrazine (DIA) and deethylatrazine (DEA), was performed in ground and surface waters from Primavera do Leste region, Mato Grosso state (Middle West of Brazil). The analytical procedure was based on solid-phase extraction (SPE) with Sep-Pak C18 disposable cartridges and ethyl acetate for elution solvent. Residue levels were determined by gas chromatography with nitrogen-phosphorus detection. For most of the pesticides average recoveries at different fortification levels were >with relative standard deviation < The recoveries of DIA and trifluralin in water were 25% and 56%, respectively, which were attributed to the incomplete retention of DIA and strong retention on the sorbing material and high volatility of trifluralin. Detection limits ranged from 0.023 to 0.088 μg L-1. This method was applied for the analysis of 5 superficial water samples and 28 groundwater samples, in places used for human consumption without previous treatment, collected in Primavera do Leste, Mato Grosso, Brazil. Results indicated that the highest level of contamination in a water sample was 1.732 μg L-1 for metolachlor, while metribuzin was the most frequently detected herbicide with maximum concentration of 0.351 μg L-1. ©2006 Sociedade Brasileira de Química.

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West syndrome is a severe epilepsy, occurring in infancy, that comprises epileptic seizures known as spasms, in clusters, and a unique EEG pattern, hypsarrhythmia, with psychomotor regression. Maturation of the brain is a crucial component. The onset is within the first year of life, before 12 months of age. Patients are classified as cryptogenic (10 to 20%), when there are no known or diagnosed previous cerebral insults, and symptomatic (80 to 90%), when associated with pre-existing cerebral damages. The time interval from a brain insult to infantile spasms onset ranged from 6 weeks to 11 months. West syndrome has a time-limited natural evolutive course, usually disappearing by 3 or 4 years of age. In 62% of patients, there are transitions to another age-related epileptic encephalopathies, the Lennox-Gastaut Syndrome and severe epilepsy with multiple independent foci. Spontaneous remission and remission after viral infections may occur. Therapy with ACTH and corticosteroids are the most effective. Reports about intravenous immunoglobulins action deserve attention. There is also immune dysfunction, characterized mainly by anergy, impaired cell-mediated immunity, presence of immature thymocytes in peripheral blood, functional impairment of T lymphocytes induced by plasma inhibitory factors, and altered levels of immunoglobulins. Changes in B lymphocytes frequencies and increased levels of activated B cells have been reported. Sensitized lymphocytes to brain extract were also described. Infectious diseases are frequent and may, sometimes, cause fatal outcomes. Increase of pro-inflamatory cytokines in serum and cerebrospinal fluid of epileptic patients were reported. Association with specific HLA antigens was described by several authors (HLA-DR7, HLA-A7, HLA-DRw52, and HLA-DR5). Auto-antibodies to brain antigens, of several natures (N-methyl-d-aspartate glutamate receptor, gangliosides, brain tissue extract, synaptic membrane, and others), were described in epileptic patients and in epileptic syndromes. Experimental epilepsy studies with anti-brain antibodies demonstrated that epileptiform discharges can be obtained, producing hyperexcitability leading to epilepsy. We speculate that in genetically prone individuals, previous cerebral lesions may sensitize immune system and trigger an autoimmune disease. Antibody to brain antigens may be responsible for impairment of T cell function, due to plasma inhibitory effect and also cause epilepsy in immature brains. © 2008 Bentham Science Publishers Ltd.

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Chartergellus golfitensis West-Eberhard new species, is described from Central America and compared with C. zonatus Spinola, a species heretofore inadequately described.

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This study aims to characterize and compare three Cerrado areas (one cerradão and two cerrado sensu stricto areas) in Patrânia, São Paulo state, southeastern Brazil, concerning the floristic composition. In total, 250 taxa were found belonging to four species of pteridophytes, one species of an exotic gymnosperm and 243 species of angiosperms. Differences in species number and proportion of the woody and herbaceous components were observed among the three Cerrado areas. The similarity analysis revealed that the cerradão seems quite peculiar, showing low similarity level with the cerrado sensu stricto areas contiguous to it, being more similar to other cerradão areas located in nearby municipalities. © 2012 Check List and Authors.