Dispersion of carbon nanotubes in polyamide 6 for microinjection moulding

The focus of this study was to investigate the dispersion state of pure and functionalized carbon nanotubes in polyamide 6, on composites prepared by twin-screw extrusion and then processed by microinjection moulding. Nanocomposites were prepared with different carbonvnanotube compositions, with and without functionalization. The nanotubes were functionalized by the 1,3-dipolar cycloaddition reaction. The dispersion of the carbon nanotube agglomerates was quantified using optical microscopy and image analysis. The effect of functionalization on the polyamide 6/carbon nanotube interface, the nanocomposite morphology and the mechanical and electrical properties were studied. It was observed that the microinjected composites with functionalized carbon nanotubes presented improved dispersion, with smaller carbon nanotube agglomerate area ratio compared to the composites with pure nanotubes. The functionalized nanotubes showed better adhesion to polyamide 6 compared to pure nanotubes, as observed by scanning electron microscopy. The incorporation of carbon nanotubes considerably improved the mechanical properties. The effect of high polymer shear rate on carbon nanotube alignment during microinjection moulding was assessed by comparing the electrical resistivity of the composite after extrusion and after microinjection moulding, through the thickness and along the flow direction. The experiments showed that the mould design and processing conditions significantly affected electrical resistivity.Fundação para a Ciência e Tecnologia (project PEst-C/CTM/LA0025/2013

Comprehensiveness and programmatic vulnerability to stds/hiv/aids in primary care

This study aimed to identify programmatic vulnerability to STDs/HIV/AIDS in primary health centers (PHCs). This is a descrip - tive and quantitative study carried out in the city of São Paulo. An online survey was applied (FormSUS platform), involving administrators from 442 PHCs in the city, with responses received from 328 of them (74.2%), of which 53.6% were nurses. At - tention was raised in relation to program - matic vulnerability in the PHCs regarding certain items of infrastructure, prevention, treatment, prenatal care and integration among services on STDs/HIV/AIDS care. It was concluded that in order to reach comprehensiveness of actions for HIV/ AIDS in primary health care, it is necessary to consider programmatic vulnerability, in addition to more investment and reor - ganization of services in a dialogue with the stakeholders (users, multidisciplinary teams, and managers, among others)

Avaliação do curso de gerenciamento online na perspectiva dos egressos

RESUMO Objetivo Avaliar curso online na perspectiva do egresso e verificar a relação entre variáveis. Método Estudo quantitativo, descritivo e exploratório, aplicado aos participantes no final de três versões de um curso de atualização onlinena temática de Gerenciamento em Enfermagem. Resultados Os índices de satisfação nas três categorias elencadas, em três anos, apresentaram resultados acima de 75,0%. Os coeficientes obtidos indicaram alta consistência do questionário. Considerando o índice total, a categoria Desempenho do tutor foi a de índice mais alto. Fortes associações entre Autoavaliação e Desempenho do tutor, Autoavaliação e Programa do curso e Desempenho do tutor e Programa do curso foram identificadas. Não houve associação entre as três categorias referidas com as demais variáveis do estudo. Conclusão Os egressos demonstraram satisfação com o curso, que favoreceu a interação e a promoção do conhecimento coletivo no gerenciamento em enfermagem. Foram reconhecidos, também, aspectos que carecem de melhorias, com destaque à capacitação do tutor para mediar discussões e estimular o envolvimento do estudante ao longo do curso

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector

Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT

Measurement of the production of a W boson in association with a charm quark in pp collisions at √s = 7 TeV with the ATLAS detector

The production of a W boson in association with a single charm quark is studied using 4.6 fb−1 of pp collision data at s√ = 7 TeV collected with the ATLAS detector at the Large Hadron Collider. In events in which a W boson decays to an electron or muon, the charm quark is tagged either by its semileptonic decay to a muon or by the presence of a charmed meson. The integrated and differential cross sections as a function of the pseudorapidity of the lepton from the W-boson decay are measured. Results are compared to the predictions of next-to-leading-order QCD calculations obtained from various parton distribution function parameterisations. The ratio of the strange-to-down sea-quark distributions is determined to be 0.96+0.26−0.30 at Q 2 = 1.9 GeV2, which supports the hypothesis of an SU(3)-symmetric composition of the light-quark sea. Additionally, the cross-section ratio σ(W + +c¯¯)/σ(W − + c) is compared to the predictions obtained using parton distribution function parameterisations with different assumptions about the s−s¯¯¯ quark asymmetry

Evidence for the Higgs-boson Yukawa coupling to tau leptons with the ATLAS detector

Results of a search for H → τ τ decays are presented, based on the full set of proton-proton collision data recorded by the ATLAS experiment at the LHC during 2011 and 2012. The data correspond to integrated luminosities of 4.5 fb−1 and 20.3 fb−1 at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV respectively. All combinations of leptonic (τ → `νν¯ with ` = e, µ) and hadronic (τ → hadrons ν) tau decays are considered. An excess of events over the expected background from other Standard Model processes is found with an observed (expected) significance of 4.5 (3.4) standard deviations. This excess provides evidence for the direct coupling of the recently discovered Higgs boson to fermions. The measured signal strength, normalised to the Standard Model expectation, of µ = 1.43 +0.43 −0.37 is consistent with the predicted Yukawa coupling strength in the Standard Model

Measurements of fiducial and differential cross sections for Higgs boson production in the diphoton decay channel at s√=8 TeV with ATLAS

Measurements of fiducial and differential cross sections are presented for Higgs boson production in proton-proton collisions at a centre-of-mass energy of s√=8 TeV. The analysis is performed in the H → γγ decay channel using 20.3 fb−1 of data recorded by the ATLAS experiment at the CERN Large Hadron Collider. The signal is extracted using a fit to the diphoton invariant mass spectrum assuming that the width of the resonance is much smaller than the experimental resolution. The signal yields are corrected for the effects of detector inefficiency and resolution. The pp → H → γγ fiducial cross section is measured to be 43.2 ±9.4(stat.) − 2.9 + 3.2 (syst.) ±1.2(lumi)fb for a Higgs boson of mass 125.4GeV decaying to two isolated photons that have transverse momentum greater than 35% and 25% of the diphoton invariant mass and each with absolute pseudorapidity less than 2.37. Four additional fiducial cross sections and two cross-section limits are presented in phase space regions that test the theoretical modelling of different Higgs boson production mechanisms, or are sensitive to physics beyond the Standard Model. Differential cross sections are also presented, as a function of variables related to the diphoton kinematics and the jet activity produced in the Higgs boson events. The observed spectra are statistically limited but broadly in line with the theoretical expectations