Measurement of the Top Quark Mass in the Dilepton Channel

We report a measurement of the top quark mass using six candidate events for the process pbarp->ttbar->l^+ nu l^- nubar b bbar + X, observed in the D0 experiment at the Fermilab ppbar collider. Using maximum likelihood fits to the dynamics of the decays, we measure a mass for the top quark of m(top) = 168.4 +- 12.3 (stat) +- 3.6 (syst) GeV/c^2. We combine this result with our previous measurement in the ttbar->l+jets channel to obtain m(top) = 172.1 +- 7.1 GeV/c^2 as the best value of the mass of the top quark measured by D0.Comment: 48 pages, 22 figures (encapsultaed postscript), Submitted for publication in Physical Review

Deposição e distribuição de calda de pulverização em plantas de feijoeiro (Phaseolus vulgaris) e capim-braquiária (Brachiaria decumbens)

Com o objetivo de avaliar a deposição e distribuição de solução traçante em plantas de feijoeiro e capim-braquiária, foi conduzido experimento no NuPAM-FCA/ UNESP, campus de Botucatu-SP, utilizando um simulador de pulverização em ambiente controlado. Os tratamentos utilizados foram: bico jato plano XR Teejet (XR110.02VS) + surfactante Aterbane BR (0,5% v/v); bico jato cônico Conejet (TXVK-4) + surfactante Aterbane BR (0,5% v/v); bico jato plano XR Teejet (XR110.02VS); e bico jato cônico Conejet (TXVK-4). em todos os tratamentos foi aplicada uma solução de NaCl (0,5% p/v) + corante Poliglow laranja (0,5% p/v) + mancozeb (0,5% p/v). As unidades experimentais constituíram-se de vasos com duas plantas-alvo de capim-braquiária posicionadas sob uma planta-alvo de feijoeiro. A visualização da distribuição das gotas nas folhas de capim-braquiária foi efetuada com auxílio de luz negra, e o depósito da calda na superfície das plantas foi quantificado através da condutividade elétrica da solução aplicada e coletada por meio de lavagem de ambos os alvos. Os bicos de pulverização, jato plano (XR Teejet) e cônico (Conejet), não apresentaram diferença no depósito nos folíolos totais de feijoeiro quando submetidos a mesma condição de calda de pulverização. No entanto, o bico jato plano XR Teejet (XR110.02VS) e o bico jato cônico Conejet (TXVK-4) proporcionaram aumento de 67,1 e 61,5% na deposição da calda em relação a área foliar e 106,4 e 66,9% para matéria seca, respectivamente, em relação ao bico jato plano XR Teejet (XR110.02VS) + surfactante Aterbane BR (0,5% v/v) e ao bico jato cônico Conejet (TXVK-4) + surfactante Aterbane BR (0,5% v/v). Para o capim-braquiária, o bico cônico Conejet proporcionou deposição superior e distribuição mais uniforme em relação ao jato plano XR Teejet.An experiment was carried out at the NuPAM-FCA/UNESP, Botucatu Campus, São Paulo, Brazil, to estimate the deposition and distribution of a marker solution on the P. vulgaris and B. decumbens plants, using a sprayer simulator under a controlled environment. The treatments were: nozzle fan jet XR Teejet (XR110.02VS) + surfactant (Aterbane BR - 0.5% v/v); nozzle Conejet (TXVK-4) + surfactant (Aterbane BR - 0.5% v/v); nozzle fan jet XR Teejet (XR110.02VS) and nozzle Conejet (TXVK-4). A solution of NaCl (0.5%) + Orange Poliglow colour (0.5%) + mancozeb (0.5%) was applied in all treatments. The experimental units consisted of pots with two B. decumbens target plants underneath one P. vulgaris target plant. Droplet distribution over B. decumbens leaves was evaluated with black light, and deposition by electric conductivity of the sprayer solution collected by washing the targets in deionized water. The spraying nozzles, XR Teejet and Conejet, did not show deposition difference on P. vulgaris leaves, under equal spray solution conditions. However, the nozzle with fan jet XR Teejet (XR110.02VS) and the nozzle Conejet (TXVK-4) provided, respectively, 67.1% and 61.5% increase on the leaf area deposition and 106,4% and 66.9% increase dry weight increase, when compared to the nozzle with fan jet XR Teejet (XR110.02VS) + surfactant (Aterbane BR - 0.5% v/v) and the nozzle Conejet (TXVK-4) + surfactant (Aterbane BR - 0.5% v/v). Nozzle Conejet provided higher uniform distribution, when compared to nozzle XR Teejet

Environment and anthropogenic activities influence cetacean habitat use in southeastern Brazil

Investigating the influence of coastal development on marine environments is a priority to maintain healthy seas. Cetaceans are top predators, keystone and umbrella species and thus are good candidate models to evaluate the extent of anthropogenic impacts on coastal habitats. We employed a generalized linear model with spatial eigenvector mapping (SEV-GLM) to understand the influence of environmental and anthropogenic activities on migrant (humpback whale Megaptera novaeangliae) and non-migrant (Bryde’s whale Balaenoptera brydei and common bottlenose dolphin Tursiops truncatus) cetacean habitat use off Cabo Frio, Rio de Janeiro, Brazil. We hypothesized that both environmental and anthropogenic activities influence their habitat use. Data were collected during 118 boat trips between December 2010 and June 2014. The best SEV-GLM predicted humpback whales would increase linearly with distance to coast, with minimum sea surface temperature (SST) around 19.4-19.8°C and maximum SST around 25.5-26°C, with low variations in chlorophyll a (chl a) concentrations. The model also predicted that humpback whales would occur up to 10 km from diving areas, increasing linearly with distance to fishing grounds. The best non-migrant cetacean SEV-GLM predicted that they would occur more frequently around depths from 30-60 m, increasing with low SST and high chl a concentration. For the anthropogenic component, the model predicted that non-migrant cetaceans would occur up to 10 km from fishing grounds. Our study modeled the influence of anthropogenic activities on cetaceans, and indicates specific priority areas for cetacean conservation, contributing at a local and national scale

Composição do líquido sinovial de cães com ruptura do ligamento cruzado cranial Composition of the synovial fluid of dogs with the cranial cruciate ligament rupture

As características do líquido sinovial de ambas articulações fêmoro-tíbio-patelares de animais portadores de ruptura do ligamento cruzado cranial unilateral foram estudados em seis cães adultos. Os parâmetros macroscópicos observados foram cor, volume, viscosidade, turbidez, coagulação e teste de mucina. Os parâmetros microscópicos foram a contagem global e diferencial de células. Em dois animais, a viscosidade manteve-se normal e no restante apresentou-se diminuída. O resultado do teste de mucina foi normal em todos os animais e não ocorreu coagulação do fluido quando em contato com o ar. A contagem diferencial de células manteve-se dentro dos padrões normais, citados na literatura. Portanto, nos casos de ruptura do ligamento cruzado cranial, o líquido sinovial da articulação do joelho pode permanecer dentro dos padrões normais que o caracterizam, quanto aos aspectos macroscópicos. A composição celular global e relativa do líquido sinovial da articulação afetada apresenta respectivamente contagem superior e diferente a da articulação normal, embora dentro dos padrões fisiológicos citados na literatura.<br>The characteristics of the synovial fluid of both stifle joints from dogs with unilateral cranial cruciate ligament rupture were studied in six adult dogs. The macroscopic parameters observed were color, volume, viscosity, turbidity, and coagulation. In addition, mucin tests were performed. The microscopic parameters were global cell counting and differential cell counting. Two animals presented normal viscosity and in the others the viscosity was reduced. The result of the mucin test was normal in all animals and there was no coagulation of the fluid when in contact with the air. The differential cell counting was maintained within regular standards cited in the literature. Therefore, in the cases of cranial cruciate ligament rupture, the synovial fluid of the stifle joint can stay without any macroscopic change. Although the global and relative cell composition of the affected joint synovial fluid were kept within regular standards according to the literature, they were consistently higher than that of the normal joint