Observation of Z decays to four leptons with the CMS detector at the LHC

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Measurement of the relative prompt production rate of chi(c2) and chi(c1) in pp collisions at root s=7 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Caracterização da piscicultura na região do Vale do Ribeira - SP

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

Conteúdo de peptídeos e avaliação morfofisiológica dos espermatozóides do epidídimo e ejaculado de bovinos

Objetivou-se com este estudo a identificação de alguns fatores protéicos envolvidos na qualidade funcional dos espermatozóides epididimais (SPZEP) e ejaculados (SPZEJ) de bovinos. Foram avaliadas as características morfofisiológicas e analisado o conteúdo peptídico destas estruturas de 11 animais mestiços Nelore, de 24 a 30 meses de idade. As avaliações morfofisiológicas foram motilidade progressiva (MOT, %), vigor, patologias espermáticas, integridade acrossômica e da cromatina. Foi observado que, os SPZEJ, na média, apresentaram MOT maior do que os SPZEP, 72,3 e 46,4%, respectivamente. Considerando as patologias espermáticas, taxas de defeitos maiores (DEFMAI), menores (DEFMEN) e totais (DEFTOT), houve diferença significativa entre as taxas dos DEFMEN e DEFTOT dos SPZEP e SPZEJ, sendo, em média, 91,1 e 8,5% e 95,4 e 11,8%, respectivamente. As taxas dos DEFMEN e DEFTOT dos SPZEP foram maiores em função da presença de espermatozóides com gotas citoplasmáticas distais. A análise das protéinas dos SPZEP e SPZEJ foi realizada por espectrometria de massa, método MALDI-TOF (matrix -assisted laser desorption/ionization - time of flight), e revelou presença de peptídeos de massa molecular variando de 1,1 a 26,3 kDa nos SPZEJ e de 1,1 a 11,6 kDa nos SPZEP. Foram identificados peptídeos de 10,6 e 13,4 kDa somente nos SPZEJ e de 6,8 kDa somente nos SPZEP. Foi observada relação do peptídeo de massa molecular de 7,4 kDa dos SPZEP e de 4,7 kDa dos SPZEJ, com a MOT Ê 80%, destas estruturas. Os resultados sugerem o envolvimento destes peptídeos nos processos funcionais das células espermáticas do epidídimo e ejaculado. O estudo utilizou o método MALDI/TOF para espectrômetro de massa, para identificar peptídeos em espermatozóides do epidídimo de bovinos, pela primeira vez no País.

Cytochemistry and polarization microscopy of amphibian sperm cell nuclei presumed to differ in basic protein composition

The pattern of availability of free DNA phosphates, and the kind of DNA-protein complex arrangement, both induced by nuclear basic proteins, and the richness in arginine residues in these proteins were investigated cytochemically and cytophysically in spermatozoa of the South-American Hylidae species, Hyla fuscovaria and Hyla biobeba. The aim was to demonstrate differences at the level of sperm histones in two species of Hyla until recently considered to be congeneric. The results indicated differences in the spermatozoal nuclear basic proteins and DNA-protein complexes when the two species were compared. The spermatozoa of Hyla biobeba were assumed to be likely to contain a Bloch's ''type 3'' protein type (intermediate sperm basic protein), similarly to Hyla species of North and Central America. on the other hand, the data obtained for the spermatozoa of Hyla fuscovaria indicated that they contain a protamine or protamine-like protein, differing from Hyla biobeba and Hyla species of North and Central America. It is suggested that the differences reported here may be genus-specific, since Hyla fuscovaria has recently been reclassified as Scinax fuscovaria based on parameters other than sperm histone types. These findings are in agreement with the general view of a wide variability in sperm nuclear proteins in the Anura group.

Fermion localization on degenerate and critical branes

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comparison of proton energy loss in thick absorbers in terms of a reduced calibration curve

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Fermion localization on two-field thick branes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Soliton propagation in a medium with Kerr nonlinearity and resonant impurities: A variational approach

The soliton propagation in a medium with Kerr nonlinearity and resonant impurities was studied by a variational approach. The existence of a solitary wave was shown within the framework of a combined nonintegrable system composed of one nonlinear Schrödinger and a pair of Bloch equations. The analytical solution which was obtained, was tested through numerical simulations confirming its solitary wave nature.

Search for the flavor-changing neutral current decay Bs 0 → μ+ μ- pp̄ Collisions at √s = 1.96 TeV with the DO Detector

We present the results of a search for the flavor-changing neutral current decay Bs 0 → μ+ μ-. using a data set with integrated luminosity of 240 pb-1 of pp̄ collisions at √s = 1.96 TeV collected with the D0 detector in run II of the Fermilab Tevatron collider. We find the upper limit on the branching fraction to be B(Bs 0 → μ+ π-) ≤ 5.0 × 10-7 at the 95% C.L. assuming no contributions from the decay Bd 0 → μ+ μ- in the signal region. This limit is the most stringent upper bound on the branching fraction Bs 0 → μ+ μ- to date. © 2005 The American Physical Society.

Measurement of the pp(-)-> W gamma plus X cross section at root s=1.96 TeV and WW gamma anomalous coupling limits

The WWγ triple gauge boson coupling parameters are studied using pp̄rarr; νγ+X(=e,μ) events at s=1.96 TeV. The data were collected with the D0 detector from an integrated luminosity of 162pb-1 delivered by the Fermilab Tevatron Collider. The cross section times branching fraction for pp̄→W(γ)+X→ νγ+X with ETγ>8 GeV and ΔR γ> 0.7 is 14.8±1.6(stat)±1.0(syst) ±1.0(lum)pb. The one-dimensional 95% confidence level limits on anomalous couplings are -0.88<Δκγ<0.96 and -0. 20<λγ<0.20. © 2005 The American Physical Society.

Measurement of the tt̄ production cross section in pp̄ collisions at √s = 1.96 TeV in dilepton final states

We present a measurement of the top quark pair (tt̄) production cross section in pp̄ collisions at √s=1.96 TeV using events with two charged leptons in the final state. This analysis utilizes an integrated luminosity of 224-243 pb-1 collected with the DØ detector at the Fermilab Tevatron Collider. We observe 13 events in the e+e -, eμ and μ+μ- channels with an expected background of 3.2±0.7 events. For a top quark mass of 175 GeV, we measure a tt̄ production cross section of σtt̄=8. 6-2.7 +3.2(stat)±1.1(syst)±0.6(lumi) pb, consistent with the standard model prediction. © 2005 Elsevier B.V. All rights reserved.

Search for squarks and gluinos in events with jets and missing transverse energy in p(p)over-bar collisions at root s-=1.96 TeV

The results of a search for squarks and gluinos using data from p over(p, ̄) collisions recorded at a center-of-mass energy of 1.96 TeV by the DØ detector at the Fermilab Tevatron Collider are reported. The topologies analyzed consist of acoplanar-jet and multijet events with large missing transverse energy. No evidence for the production of squarks or gluinos was found in a data sample of 310 pb-1. Lower limits of 325 and 241 GeV were derived at the 95% C.L. on the squark and gluino masses, respectively, within the framework of minimal supergravity with tan β = 3, A0 = 0, and μ < 0. © 2006 Elsevier B.V. All rights reserved.