1,316 research outputs found

    Carrapato e vermes: inimigos do gado e do produtor.

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    bitstream/item/65290/1/CT-95-Carrapato-e-vermes.pd

    Coherent States Expectation Values as Semiclassical Trajectories

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    We study the time evolution of the expectation value of the anharmonic oscillator coordinate in a coherent state as a toy model for understanding the semiclassical solutions in quantum field theory. By using the deformation quantization techniques, we show that the coherent state expectation value can be expanded in powers of \hbar such that the zeroth-order term is a classical solution while the first-order correction is given as a phase-space Laplacian acting on the classical solution. This is then compared to the effective action solution for the one-dimensional \f^4 perturbative quantum field theory. We find an agreement up to the order \l\hbar, where \l is the coupling constant, while at the order \l^2 \hbar there is a disagreement. Hence the coherent state expectation values define an alternative semiclassical dynamics to that of the effective action. The coherent state semiclassical trajectories are exactly computable and they can coincide with the effective action trajectories in the case of two-dimensional integrable field theories.Comment: 20 pages, no figure

    Carrapato dos bovinos: controle estratégico nas diferentes regiões brasileiras.

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    bitstream/item/65401/1/COT-36-Carrapato-dos-bovinos.pd

    Pattern of mtDNA Variation in Three Populations from São Tomé e Príncipe

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    We have analysed the matrilineal genetic composition of three self-reported ethnic groups from São Tomé e Príncipe (Gulf of Guinea), an African archipelago whose settlement begun in the late fifteenth century. Sequence data from the hypervariable segments I (HVS-I) and II (HVS-II) were obtained for 30 Angolares, 35 Forros and 38 Tongas. The repertory of mtDNA lineages in São Tomé e Príncipe denoted a fully African maternal pool, primarily arisen from a Central/Southwestern substratum. The absence of any lineages of putative European descent means that the European impact at the mitochondrial pool was virtually nil. Angolares showed a clear reduction of mtDNA diversity and a slight genetic differentiation relative to Tongas or Forros, whereas the latter two groups did not present any signs of genetic boundaries between each other. The data obtained here reinforce the depiction of genetic substructuring in São Tomé e Príncipe previously derived from Y-chromosome STRs. In addition, the crossing of mtDNA and Y-STR information led to the inference that the female mediated gene flow within the archipelago was less restricted than the male, a pattern that could be framed in the cultural traditions and socio-historical interactions among the groups

    Mitochondrial portrait of the Cabo Verde archipelago: the Senegambian outpost of Atlantic slave trade

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    In order to study the matrilineal genetic composition in Cabo Verde (Republic of Cape Verde), an archipelago that used to serve as a Portuguese entrepôt of the Atlantic slave trade, we have analysed a total of 292 mtDNAs sampled from the seven inhabited islands for the hypervariable segment I (HVS-I) and some characteristic RFLPs of the coding regions. The different settlement history of the northwestern group of the islands is well reflected in the mtDNA pool. The total Cabo Verde sample clearly displays the characteristic mitochondrial features of the Atlantic fringe of western Africa and testifies to almost no mitochondrial input from the Portuguese colonizers.info:eu-repo/semantics/publishedVersio

    Re-evaluation of SO2 release of the 15 June 1991 Pinatubo eruption using ultraviolet and infrared satellite sensors

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    In this study, ultraviolet TOMS (Total Ozone Mapping Spectrometer) satellite data for SO2 are re-evaluated for the first 15 days following the 15 June 1991 Pinatubo eruption to reflect new data retrieval and reduction methods. Infrared satellite SO2 data from the TOVS/HIRS/2 (TIROS (Television Infrared Observation Satellite) Optical Vertical Sounder/High Resolution Infrared Radiation Sounder/2) sensor, whose data sets have a higher temporal resolution, are also analyzed for the first time for Pinatubo. Extrapolation of SO2 masses calculated from TOMS and TOVS satellite measurements 19–118 hours after the eruption suggest initial SO2 releases of 15 ± 3 Mt for TOMS and 19 ± 4 Mt for TOVS, including SO2 sequestered by ice in the early Pinatubo cloud. TOVS estimates are higher in part because of the effects of early formed sulfate. The TOMS SO2 method is not sensitive to sulfate, but can be corrected for the existence of this additional emitted sulfur. The mass of early formed sulfate in the Pinatubo cloud can be estimated with infrared remote sensing at about 4 Mt, equivalent to 3 Mt SO2. Thus the total S release by Pinatubo, calculated as SO2, is 18 ± 4 Mt based on TOMS and 19 ± 4 Mt based on TOVS. The SO2removal from the volcanic cloud during 19–374 hours of atmospheric residence describes overall e-folding times of 25 ± 5 days for TOMS and 23 ± 5 days for TOVS. These removal rates are faster in the first 118 hours after eruption when ice and ash catalyze the reaction, and then slow after heavy ash and ice fallout. SO2 mass increases in the volcanic cloud are observed by both TOMS and TOVS during the first 70 hours after eruption, most probably caused by the gas-phase SO2release from sublimating stratospheric ice-ash-gas mixtures. This result suggests that ice-sequestered SO2 exists in all tropical volcanic clouds, and at least partially explains SO2 mass increases observed in other volcanic clouds in the first day or two after eruption

    Desenvolvimento inicial de Plátano CV. D'Angola irrigado em diferentes populações.

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    O trabalho avaliou o desenvolvimento inicial da bananeira cv. D'Angola, tipo plátano, conduzidas no Distrito Irrigado Jaguaribe-Apodi (DIJA), em Limoeiro do Norte, Ceará, Brasil. As populações de 1.111 (Testemunha), 2.500, 2.778, 3.125, 3.571 e 4.167 plantas por hectare, obtidas, respectivamente, nos arranjos 3,0 x 3,0 m, 2,0 x 2,0 m, 2,0 x 1,8 m, 2,0 x 1,6 m, 2,0 x 1,4 m e 2,0 x 1,2 m, foram avaliadas aos 113 e 140 dias após o plantio (05/11/2014). Entre as avaliações, houve aumento de 20,9% no diâmetro do pseudocaule (15,3 a 18,5 cm), de 33,6% na altura da planta (160,5 a 214,4 cm) e de 11,5% no número de folhas vivas por planta (11,3 a 12,6 unidades). Em relação à testemunha, o tratamento com 3.125 plantas por hectare foi o único superior quanto ao diâmetro do pseudocaule (18 cm vs. 14.4 cm). Todos foram superiores quanto a altura da planta (187,5 vs. 144,0 cm) e semelhantes quanto ao número de folhas vivas (Dunnett, p < 0,05). Houve efeito linear para populações quanto ao número de folhas (y=10,6312+0,0004*x R²=50%)
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