Relating the quark and gluon condensâtes through the QCD vacuum energy

Using the Cornwall-Jackiw-Tomboulis effective potential for composite operators we compute the QCD vacuum energy as a function of the dynamical quark and gluon propagators, which are related to their respective condensâtes as predicted by the operator product expansion. The identification of this result to the vacuum energy obtained from the trace of the energy-momentum tensor allows us to study the gluon self-energy, verifying that it is fairly represented in the ultraviolet by the asymptotic behavior predicted by the operator product expansion, and in the infrared it is frozen at its asymptotic value at one scale of the order of the dynamical gluon mass. We also discuss the implications of this identity for heavy and light quarks. For heavy quarks we recover, through the vacuum energy calculation, the relation nij{filif)-îi(asl'n)GlivGllv obtained many years ago with QCD sum rules. ©2000 The American Physical Society.

Charmed-meson scattering on nucleons in a QCD Coulomb gauge quark model

The scattering of charmed mesons on nucleons is investigated within a chiral quark model inspired on the QCD Hamiltonian in Coulomb gauge. The microscopic model incorporates a longitudinal Coulomb confining interaction derived from a self-consistent quasi-particle approximation to the QCD vacuum, and a traverse hyperfine interaction motivated from lattice simulations of QCD in Coulomb gauge. From the microscopic interactions at the quark level, effective meson-baryon interactions are derived using a mapping formalism that leads to quark-Born diagrams. As an application, the total cross-section of heavy-light D-mesons scattering on nucleons is estimated.

Search for heavy bottom-like quarks in 4.9 fb-1 of pp collisions at √s = 7 TeV

Results are presented from a search for heavy bottom-like quarks, pair-produced in pp collisions at √s = 7TeV, undertaken with the CMS experiment at the LHC. The b′ quarks are assumed to decay exclusively to tW. The b′b̄′ → tW-t̄W+ process can be identified by its distinctive signatures of three leptons or two leptons of same charge, and at least one b-quark jet. Using a data sample corresponding to an integrated luminosity of 4.9 fb-1, observed events are compared to the standard model background predictions, and the existence of b′ quarks having masses below 611 GeV/c2 is excluded at 95% confidence level.

Search for a W' boson decaying to a bottom quark and a top quark in pp collisions at s=7TeV

Results are presented from a search for a W' boson using a dataset corresponding to 5.0fb-1 of integrated luminosity collected during 2011 by the CMS experiment at the LHC in pp collisions at s=7TeV. The W' boson is modeled as a heavy W boson, but different scenarios for the couplings to fermions are considered, involving both left-handed and right-handed chiral projections of the fermions, as well as an arbitrary mixture of the two. The search is performed in the decay channel W'→tb, leading to a final state signature with a single electron or muon, missing transverse energy, and jets, at least one of which is identified as a b-jet. A W' boson that couples to the right-handed (left-handed) chiral projections of the fermions with the same coupling constants as the W is excluded for masses below 1.85 (1.51) TeV at the 95% confidence level. For the first time using LHC data, constraints on the W' gauge couplings for a set of left- and right-handed coupling combinations have been placed. These results represent a significant improvement over previously published limits. © 2012 CERN.

Search for heavy resonances in the W/Z-tagged dijet mass spectrum in pp collisions at 7 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Search for Top-Quark Partners with Charge 5/3 in the Same-Sign Dilepton Final State

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Dressed perturbation theory for the quark propagator: Fernando Enrique Serna Algarín. -

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Search for long-lived neutral particles decaying to quark-antiquark pairs in proton-proton collisions at root s=8 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Searches for heavy Higgs bosons in two-Higgs-doublet models and for t→ch decay using multilepton and diphoton final states in pp collisions at 8 TeV

Searches are presented for heavy scalar (H) and pseudoscalar (A) Higgs bosons posited in the two doublet model (2HDM) extensions of the standard model (SM). These searches are based on a data sample of pp collisions collected with the CMS experiment at the LHC at a center-of-mass energy of root s = 8 TeV and corresponding to an integrated luminosity of 19.5 fb(-1). The decays H -> hh and A -> Zh, where h denotes an SM-like Higgs boson, lead to events with three or more isolated charged leptons or with a photon pair accompanied by one or more isolated leptons. The search results are presented in terms of the H and A production cross sections times branching fractions and are further interpreted in terms of 2HDM parameters. We place 95% C.L. cross section upper limits of approximately 7 pb on sigma B for H -> hh and 2 pb for A -> Zh. Also presented are the results of a search for the rare decay of the top quark that results in a charm quark and an SM Higgs boson, t -> ch, the existence of which would indicate a nonzero flavor-changing Yukawa coupling of the top quark to the Higgs boson. We place a 95% C.L. upper limit of 0.56% on B(t -> ch).

An electroanalytical application of 2-aminothiazole-modified silica gel after adsorption and separation of Hg(II) from heavy metals in aqueous solution

2-Aminothiazole covalently attached to a silica gel surface was prepared in order to obtain an adsorbent for Hg(II) ions having the following characteristics: good sorption capacity, chemical stability under conditions of use, and, especially, high selectivity. The accumulation voltammetry of mercury(II) was investigated at a carbon paste electrode chemically modified with silica gel functionalized with 2-aminothiazole (SIAMT-CPE). The repetitive cyclic voltammogram of mercury(II) solution in the potential range -0.2 to + 0.6 V versus Ag/AgCl (0.02 mol L-1 KNO3; V = 20 mV s(-1)) show two peaks one at about 0.1 V and other at 0.205 V. The anodic wave peak at 0.205 V is well defined and does not change during the cycles and it was therefore further investigated for analytical purposes using differential pulse anodic stripping voltammetry in differents supporting electrolytes. The mercury response was evaluated with respect to pH, electrode composition, preconcentration time, mercury concentration, cleaning solution, possible interferences and other variables. The precision for six determinations (n = 6) of 0.02 and 0.20 mg L-1 Hg(II) was 4.1 and 3.5% (relative standard deviation), respectively. The detection limit was estimated as 0.10 mu g L-1 mercury(II) by means of 3:1 current-to-noise ratio in connection with the optimization of the various parameters involved and using the highest-possible analyser sensitivity. (c) 2006 Elsevier Ltd. All rights reserved.

Qualitative-feed-restricted heavy swine: meat quality and morpho-histochemical characteristics of muscle fibers

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

Qualitative feed restriction for heavy swines: effect on digestibility and weight of organs of digestive tract, and environmental impact of feces

Foram utilizados 50 suínos machos castrados para avaliar o efeito da restrição alimentar qualitativa sobre a digestibilidade dos componentes dietéticos, os órgãos do trato digestório, a composição e a produção fecal. Foram utilizadas cinco dietas experimentais, com níveis de restrição qualitativa de 0, 5, 10, 15 e 20%. Houve redução linear (P<0,001) para todos os coeficientes de digestibilidade, com exceção da fibra em detergente ácido, que apresentou resposta quadrática (P<0,05). Os teores de sólidos totais (P<0,01) e voláteis (P<0,05), e minerais totais (P<0,001) nas fezes aumentaram com os níveis de restrição alimentar, enquanto os níveis de K (P<0,05), Cu (P<0,01) e de N, P, Na, Ca, Mg, Fe e Zn (P<0,001), apresentaram resposta quadrática. A excreção diária de fezes, sólidos totais e voláteis, minerais totais, N, P, K, Mn e Cu (P<0,001), Ca, Na, Mg e Fe (P<0,05) apresentaram aumento em função do nível da restrição alimentar qualitativa. A restrição qualitativa pode ser alternativa para destinação de resíduos da agroindústria, conferindo boas propriedades às fezes suínas, no que diz respeito à utilização para adubação de culturas.

Carcass characteristics and meat quality of heavy swine fed different citrus pulp levels

Foi realizado um ensaio utilizando 36 suínos machos castrados, com peso inicial de 83,7±5,1kg, para avaliar o efeito da inclusão de polpa cítrica, 0, 10, 20 e 30%, em um programa de restrição alimentar qualitativa para suínos abatidos aos 130kg de peso, sobre o peso dos órgãos do sistema digestório e sobre características da carcaça e da qualidade da carne. A inclusão de polpa cítrica proporcionou aumento linear (P<0,05) nos pesos do estômago, cólon e fígado, e efeito quadrático (P<0,05) no peso do ceco. Foi observada redução linear (P<0,05) no peso, no rendimento da carcaça e no peso do pernil, porém não houve efeito (P>0,05) sobre o rendimento do pernil. Maior inclusão de polpa cítrica não foi suficiente para reduzir a espessura do toucinho e aumentar a quantidade de carne magra na carcaça, mostrando que a restrição alimentar qualitativa não foi eficiente. Foi observado aumento linear (P<0,05) do pH da carcaça resfriada e linear negativo (P<0,05) sobre as variáveis indicativas de cor da carne em função da inclusão da polpa cítrica nas dietas. A adição de polpa cítrica em programas de restrição alimentar qualitativa não foi eficiente. Por não promover nenhum efeito deletério sobre as características da carne, a polpa cítrica pode ser utilizada como ingrediente alternativo para suínos em terminação.

Ultrathin films of lignins as a potential transducer in sensing applications involving heavy metal ions

Lignins extracted from sugar cane bagasse using different alcohols in the organosolv-CO(2) supercritical pulping process have been applied in the fabrication of ultrathin films through the Langmuir-Blodgett technique. Langmuir films were characterized by surface pressure versus mean molecular area (Pi-A) isotherms to exploit the sensitivity of nanostructured lignin films to metallic ions (Cu(2+), Cd(2+) and Pb(2+)). The Pi-A isotherms were shifted to larger molecular areas when heavy metal ions are present into the subphase, which might be related to electrostatic repulsions between metallic ions entrapped within the lignin molecular structure. Taking the advantage of metal incorporation, Langmuir monolayers were transferred onto solid substrates forming Langmuir-Blodgett (LB) films to be used as a transducer in an "electronic tongue" system to detect Cu(2+) in aqueous solution below threshold standard established by the Brazilian regulation. Both techniques impedance spectroscopy and electrochemistry have been used in these experiments. Complementary, Fourier transform infrared (FTIR) spectroscopy recorded for LB films before and after soaking into Cu(2+) aqueous solution revealed an interaction between the lignin phenyl groups and the metallic ion. (C) 2007 Elsevier B.V.. All rights reserved.

VO2 Kinetics During Heavy and Severe Exercise in Swimming

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