1000 resultados para Pair 22


Relevância:

30.00% 30.00%

Publicador:

Resumo:

A Swiss frontotemporal dementia (FTD) kindred with extrapyramidal-like features and without motor neuron disease shows a brain pathology with ubiquitin-positive but tau-negative inclusions. Tau and neurofilament modifications are now studied here in three recently deceased family members. No major and specific decrease of tau was observed as described by others in, e.g., sporadic cases of FTD with absence of tau-positive inclusions. However, a slight decrease of tau, neurofilament, and synaptic proteins, resulting from frontal atrophy was detected. In parallel, polymorphic markers on chromosome 17q21-22, the centromeric region of chromosome 3 and chromosome 9, were tested. Haplotype analysis showed several recombination events for chromosomes 3 and 17, but patients shared a haplotype on chromosome 9q21-22. However as one of the patients exhibited Alzheimer and vascular dementia pathology with uncertain concomitant FTD, this locus is questionable. Altogether, these data indicate principally that the Swiss kindred is unlinked to locus 17q21-22, and that tau is not at the origin of FTD in this family.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

O objetivo deste trabalho foi avaliar o efeito da temperatura ambiente sobre as características morfométricas das fibras musculares do músculo flexor longo do hálux de frangos de corte alimentados com a mesma quantidade de ração (pair-feeding), isolando-se o efeito do consumo voluntário de alimento. Foram utilizados 16 frangos de corte machos, Ross, distribuídos em um delineamento inteiramente casualizado com dois tratamentos (estresse pelo calor e frio), com sete e nove repetições cada, respectivamente. Aos 43 dias de idade, o peso médio das aves estressadas pelo calor (1255 g) foi maior que o das aves estressadas pelo frio em pair-feeding (1086 g). O músculo das aves submetidas ao estresse pelo calor e pelo frio apresentou 22,82 e 27,93% de fibras brancas (FG - Fast Glycolytic), 52,76 e 47,67% de intermediárias (FOG - Fast Oxidative Glycolytic) e 24,42 e 24,40% de vermelhas (SO - Slow Oxidative), respectivamente. O diâmetro das fibras FG foi maior no músculo das aves submetidas ao calor (48,69 mm), quando comparado ao das aves submetidas ao frio (37,74 mm). A freqüência e o número dos tipos de fibras no músculo não diferiram entre as aves estressadas pelo calor e pelo frio. O estresse pelo frio associado à limitação no consumo de alimento determinou redução no crescimento e alterou a composição dos tipos de fibras no músculo flexor longo do hálux de frangos de corte, reduzindo o tamanho das fibras do tipo FG e mantendo o tamanho das fibras SO e FOG, as quais apresentam metabolismo oxidativo, associado à maior produção de calor.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

A search for the pair production of a heavy, narrow resonance decaying into two jets has been performed using events collected in √s=7 TeV pp collisions with the CMS detector at the LHC. The data sample corresponds to an integrated luminosity of 5.0 fb-1. Events are selected with at least four jets and two dijet combinations with similar dijet mass. No resonances are found in the dijet mass spectrum. The upper limit at 95% confidence level on the product of the resonance pair production cross section, the branching fractions into dijets, and the acceptance varies from 0.22 to 0.005 pb, for resonance masses between 250 and 1200 GeV. Pair-produced colorons decaying into qq̄ are excluded for coloron masses between 250 and 740 GeV. © 2013 CERN. citation, and DOI.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

A search for a standard model Higgs boson decaying into a pair of tau leptons is performed using events recorded by the CMS experiment at the LHC in 2011 and 2012. The dataset corresponds to an integrated luminosity of 4.9 fb(-1) at a centre-of-mass energy of 7 TeV and 19.7 fb(-1) at 8 TeV. Each tau lepton decays hadronically or leptonically to an electron or a muon, leading to six different final states for the tau-lepton pair, all considered in this analysis. An excess of events is observed over the expected background contributions, with a local significance larger than 3 standard deviations for m (H) values between 115 and 130 GeV. The best fit of the observed H -> tau tau signal cross section times branching fraction for m(H) = 125 GeV is 0.78 +/- 0.27 times the standard model expectation. These observations constitute evidence for the 125 GeV Higgs boson decaying to a pair of tau leptons.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

We determined the complete genome sequences of both biotypes of a virus pair of bovine viral diarrhea virus (BVDV) subgenotype 1k. The viruses were isolated from a persistently infected calf suffering from mucosal disease. Compared to the noncytopathic biotype, the cytopathic biotype contains an insertion of 84 nucleotides and 22 nucleotide changes.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The ATLAS experiment at the LHC has measured the production cross section of events with two isolated photons in the final state, in proton-proton collisions at root s = 7 TeV. The full data set collected in 2011, corresponding to an integrated luminosity of 4.9 fb(-1), is used. The amount of background, from hadronic jets and isolated electrons, is estimated with data-driven techniques and subtracted. The total cross section, for two isolated photons with transverse energies above 25 GeV and 22 GeV respectively, in the acceptance of the electromagnetic calorimeter (vertical bar eta vertical bar < 1.37 and 1.52 < vertical bar eta vertical bar 2.37) and with an angular separation Delta R > 0.4, is 44.0(-4.2)(+3.2) pb. The differential cross sections as a function of the di-photon invariant mass, transverse momentum, azimuthal separation, and cosine of the polar angle of the largest transverse energy photon in the Collins-Soper di-photon rest frame are also measured. The results are compared to the prediction of leading-order parton-shower and next-to-leading-order and next-to-next-to-leading-order parton-level generators.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Rising levels of atmospheric CO2 are responsible for a change in the carbonate chemistry of seawater with associated pH drops (acidification) projected to reach 0.4 units from 1950 to 2100. We investigated possible indirect effects of seawater acidification on the feeding, fecundity, and hatching success of the calanoid copepod Acartia grani, mediated by potential CO2-induced changes in the nutritional characteristics of their prey. We used as prey the autotrophic dinoflagellate Heterocapsa sp., cultured at three distinct pH levels (control: 8.17, medium: 7.96, and low: 7.75) by bubbling pure CO2 via a computer automated system. Acartia grani adults collected from a laboratory culture were acclimatized for 3 d at food suspensions of Heterocapsa from each pH treatment (ca. 500 cells/ml; 300 ?g C/l). Feeding and egg production rates of the preconditioned females did not differ significantly among the three Heterocapsa diets. Egg hatching success, monitored once per day for the 72 h, did not reveal significant difference among treatments. These results are in agreement with the lack of difference in the cellular stoichiometry (C : N, C : P, and N : P ratios) and fatty acid concentration and composition encountered between the three tested Heterocapsa treatments. Our findings disagree with those of other studies using distinct types of prey, suggesting that this kind of indirect influence of acidification on copepods may be largely associated with interspecific differences among prey items with regard to their sensitivity to elevated CO2 levels.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

In most organisms, the mismatch repair (MMR) system plays an important role in substantially lowering mutation rates and blocking recombination between nonidentical sequences. In Saccharomyces cerevisiae, the products of three genes homologous to Escherichia coli mutS—MSH2, MSH3, and MSH6—function in MMR by recognizing mispaired bases. To determine the effect of MMR on single-base pair mismatches, we have measured reversion rates of specific point mutations in the CYC1 gene in both wild-type and MMR-deficient strains. The reversion rates of all of the point mutations are similar in wild-type cells. However, we find that in the absence of MSH2 or MSH6, but not MSH3, reversion rates of some mutations are increased by up to 60,000-fold, whereas reversion rates of other mutations are essentially unchanged. When cells are grown anaerobically, the reversion rates in MMR-deficient strains are decreased by as much as a factor of 60. We suggest that the high reversion rates observed in these MMR-deficient strains are caused by misincorporations opposite oxidatively damaged bases and that MMR normally prevents these mutations. We further suggest that recognition of mispairs opposite damaged bases may be a more important role for MMR in yeast than correction of errors opposite normal bases.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

We construct parent Hamiltonians involving only local 2-body interactions for a broad class of projected entangled pair states (PEPS). Making use of perturbation gadget techniques, we define a perturbative Hamiltonian acting on the virtual PEPS space with a finite order low energy effective Hamiltonian that is a gapped, frustration-free parent Hamiltonian for an encoded version of a desired PEPS. For topologically ordered PEPS, the ground space of the low energy effective Hamiltonian is shown to be in the same phase as the desired state to all orders of perturbation theory. An encoded parent Hamiltonian for the double semion string net ground state is explicitly constructed as a concrete example.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The possible existence of a sign-changing gap symmetry in BaFe2As2-derived superconductors (SC) has been an exciting topic of research in the last few years. To further investigate this subject we combine Electron Spin Resonance (ESR) and pressure-dependent transport measurements to investigate magnetic pair-breaking effects on BaFe1.9M0.1As2 (M = Mn, Co, Cu, and Ni) single crystals. An ESR signal, indicative of the presence of localized magnetic moments, is observed only for M = Cu and Mn compounds, which display very low SC transition temperature (Tc) and no SC, respectively. From the ESR analysis assuming the absence of bottleneck effects, the microscopic parameters are extracted to show that this reduction of Tc cannot be accounted by the Abrikosov-Gorkov pair-breaking expression for a sign-preserving gap function. Our results reveal an unconventional spin- and pressure-dependent pair-breaking effect and impose strong constraints on the pairing symmetry of these materials.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Universidade Estadual de Campinas . Faculdade de Educação Física