Naturally light invisible axion and local Z(13)circle times Z(3) symmetries

We show that by imposing local Z(13)circle timesZ(3) symmetries in an SU(2)circle timesU(1) electroweak model we can implement an invisible axion in such a way that (i) the Peccei-Quinn symmetry is an automatic symmetry of the classical Lagrangian, and (ii) the axion is protected from semiclassical gravitational effects. In order to be able to implement such a large discrete symmetry, and at the same time allow a general mixing in each charge sector, we introduce right-handed neutrinos and enlarge the scalar sector of the model. The domain wall problem is briefly considered.

Search for a Higgs boson produced in association with a Z boson in p(p)over-bar collisions

We describe a search for the Standard Model Higgs boson with a mass of 105 GeV/c(2) to 145 GeV/c(2) in data corresponding to an integrated luminosity of approximately 450 pb(-1) collected with the D phi detector at the Fermilab Tevatron p (p) over bar collider at a center-of-mass energy of 1.96 TeV. The Higgs boson is required to be produced in association with a Z boson, and the Z boson is required to decay to either electrons or muons with the Higgs boson decaying to a b (b) over bar pair. The data are well described by the expected background, leading to 95% confidence level cross section upper limits sigma (p (p) over bar -> ZH) x B(H -> b (b) over bar) in the range of 3.1 pb to 4.4 pb. (C) 2007 Elsevier B.V. All rights reserved.

Measurement of the shape of the boson rapidity distribution for p(p)over-bar -> Z/gamma(*)-> e(+)e(-)+X events produced at root s of 1.96 TeV

We present a measurement of the shape of the boson rapidity distribution for p (p) over bar -> Z/gamma(*)-> e(+)e(-)+X events at a center-of-mass energy of 1.96 TeV. The measurement is made for events with electron-positron mass 71 < M-ee < 111 GeV and uses 0.4 fb(-1) of data collected at the Fermilab Tevatron collider with the D0 detector. This measurement significantly reduces the uncertainties on the rapidity distribution in the forward region compared with previous measurements. Predictions of next-to-next-to-leading order (NNLO) QCD are found to agree well with the data over the full rapidity range.

Search for the standard model Higgs boson produced in association with W and Z bosons in pp collisions at root s=7 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for pair produced fourth-generation up-type quarks in pp collisions at root s=7 TeV with a lepton in the final state

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Measurement of the shape of the boson-transverse momentum distribution in p(p)over-bar -> Z/gamma*-> e(+)e(-)+X events produced at root s=1.96 TeV

We present a measurement of the shape of the Z/gamma* boson transverse momentum (q(T)) distribution in p (p) over bar -> Z/gamma(*)-> e(+)e(-)+X events at a center-of-mass energy of 1.96 TeV using 0.98 fb(-1) of data collected with the D0 detector at the Fermilab Tevatron collider. The data are found to be consistent with the resummation prediction at low q(T), but above the perturbative QCD calculation in the region of q(T)> 30 GeV/c. Using events with q(T)< 30 GeV/c, we extract the value of g(2), one of the nonperturbative parameters for the resummation calculation. Data at large boson rapidity y are compared with the prediction of resummation and with alternative models that employ a resummed form factor with modifications in the small Bjorken x region of the proton wave function.

Measurement of the Forward-Backward Charge Asymmetry and Extraction of sin(2)theta(eff)(W) in pp -> Z/gamma(*)+X -> e(+)e(-)+X Events Produced at s=1.96 TeV

We present a measurement of the forward-backward charge asymmetry (A(FB)) in pp -> Z/gamma(*)+X -> e(+)e(-)+X events at a center-of-mass energy of 1.96 TeV using 1.1 fb(-1) of data collected with the D0 detector at the Fermilab Tevatron collider. A(FB) is measured as a function of the invariant mass of the electron-positron pair, and found to be consistent with the standard model prediction. We use the A(FB) measurement to extract the effective weak mixing angle sin(2)theta(eff)(W)=0.2326 +/- 0.0018(stat)+/- 0.0006(syst).

Apoptosis in T lymphocytes from spleen tissue and peripheral blood of L. (L.) chagasi naturally infected dogs

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Determination of labile barium in petroleum-produced formation water using paper-based DGT samplers

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Radionuclide concentrations in raw and purified phosphoric acids from Brazil and their processing wastes: implications for radiation exposures

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Characterization of melanin pigment produced by Aspergillus nidulans

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Chemical composition of Rhodocyclus gelatinosus biomass produced in poultry slaughterhouse wastewater

Rhodocyclus gelatinosus R1 foi cultivado fotoautotroficamente em águas residuais de abatedouro de aves dentro de colunas de vidro (90x670 mm) durante sete dias a 31 ± 4ºC, sob anaerobiose e intensidade luminosa fornecida pela luz do dia e por três lâmpadas incandescentes (100W) mais quatro lâmpadas fluorescentes (40W). O cultivo obtido foi centrifugado (4.500xg/20 min) e liofilizado, originando a biomassa bacteriana, que continha 7,1% de umidade. A determinação da composição centesimal indicou (base seca) 67,6% de proteína bruta, 27,6% de carboidratos totais, 0,6% de lipídeos e 4,2% de cinzas. A composição em aminoácidos da fração protéica da biomassa mostrou-se semelhante à relatada na literatura para Rhodocyclus gelatinosus e para outras bactérias fotossintetizantes. A redução na DQO do efluente após o cultivo e a retirada da biomassa foi da ordem de 90%. A valiosa composição química da biomassa de Rhodocyclus gelatinosus R1 e o alto conteúdo em aminoácidos essenciais indicam o uso potencial desse produto na suplementação de ração para aves.

Structure study of Bi4Ti3O12 produced via mechanochemically assisted synthesis

Nanosized bismuth titanate was prepared via high-energy ball milling process through mechanically assisted synthesis directly from their oxide mixture of Bi2O3 and TiO2. Only Bi4Ti3O12 phase was formed after 3 h of milling time. The excess of 3 wt% Bi2O3 added in the initial mixture before milling does not improve significantly the formation of Bi4Ti3O12 phase comparing to stoichiometric mixture. The formed phase was amorphized independently of the milling time, The Rietveld analysis was adopted to determine the crystal structure symmetry, amount of amorphous phase, crystallite size and microstrains. With increasing the milling time from 3 to 12 h, the particle size of formed Bi4Ti3O12 did not reduced significantly. That was confirmed by SEM and TEM analysis. The particle size was less than 20 nm and show strong tendency to agglomeration. The electron diffraction pattern indicates that Bi4Ti3O12 crystalline powder is embedded in an amorphous phase of bismuth titanate. Phase composition and atom ratio in BIT ceramics were determined by X-ray diffraction and EDS analysis. (c) 2007 Elsevier Ltd. All rights reserved.

Synthesis and characterization of microcrystalline cellulose produced from bacterial cellulose

In this study, microcrystalline cellulose (MCC) was prepared from the acid hydrolysis of bacterial cellulose (BC) produced in culture medium of static Acetobacter xylinum. The MCC-BC produced an average particle size between 70 and 90 mu m and a degree of polymerization (DP) of 250. The characterization of samples was performed by thermogravimetric analysis, X-ray diffraction, and scanning electron microscopy (SEM). The MCC shows a lower thermal stability than the pristine cellulose, which was expected due to the decrease in the DP during the hydrolysis process. In addition, from X-ray diffractograms, we observed a change in the crystalline structure. The images of SEM for the BC and MCC show clear differences with modifications of BC fiber structure and production of particles with characteristics similar to commercial MCC.

Dihydroisocoumarins produced by Xylaria sp and Penicillium sp., endophytic fungi associated with Piper aduncum and Alibertia macrophylla

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)