The impact of hydrofluoric acid etching followed by unfilled resin on the biaxial strength of a glass-ceramic

Objectives: To evaluate the null hypotheses that hydrofluoric (HF) acid etching time would neither decrease the biaxial flexural strength of a glass-based veneering ceramic nor enhance it after silane and unfilled resin (UR) applications. Methods: Disc-shaped IPS e.max ZirPress specimens were allocated into 12 groups: G1-control (no-etching), G2-30 s, G3-60 s, G4-90 s, G5-120 s, G6-60 s + 60 s. Groups (G7-G12) were treated in the same fashion as G1-G6, but followed by silane and UR applications. Surface morphology and roughness (Ra and Rq) of the ceramics were assessed by means of scanning electron microscopy (SEM) and profilometry, respectively. Flexural strength was determined by biaxial testing. Data were analyzed by two-way ANOVA and the Sidak test (�� = 0.05). Weibull statistics were estimated and finite element analysis (FEA) was carried out to verify the stress concentration end areas of fracture. Results: The interaction (etching time vs. surface treatment) was significant for Ra (p = 0.008) and Rq (0.0075). Resin-treated groups presented significantly lower Ra and Rq than non-treated groups, except for the 60 s group (p < 0.005). SEM revealed that etching affected the ceramic microstructure and that the UR was able to penetrate into the irregularities. A significant effect of etching time (p = 0.029) on flexural strength was seen. G7-G12 presented higher strength than G1-G6 (p < 0.0001). None of experimental groups failed to show 95% confidence intervals of �� 0 and m overlapped. FEA showed lower stress concentration after resin treatment. Significance: HF acid etching time did not show a damaging effect on the ceramic flexural strength. Moreover, the flexural strength could be enhanced after UR treatment. �� 2013 Academy of Dental Materials.

Uma hist��ria ��ntima do desenho: sobre experi��ncias de forma����o do desenho & dos desenhistas

Coordena����o de Aperfei��oamento de Pessoal de N��vel Superior (CAPES)

Modelo de programa����o matem��tica para controle do crescimento da vegeta����o sob redes de distribui����o de energia el��trica

Coordena����o de Aperfei��oamento de Pessoal de N��vel Superior (CAPES)

Otimiza����o do problema de carregamento de container usando uma metaheur��stica eficiente

Coordena����o de Aperfei��oamento de Pessoal de N��vel Superior (CAPES)

Planejamento da expans��o de sistemas de transmiss��o considerando an��lise de confiabilidade e incertezas na demanda futura

Coordena����o de Aperfei��oamento de Pessoal de N��vel Superior (CAPES)

A Educa����o pela Pedra: alguns olhares sobre a arte e a educa����o no letramento de jovens e adultos

Este trabalho apresenta algumas reflex��es de educadores de jovens e adultos quando colocados, eles mesmos, como sujeitos de suas a����es numa Oficina de pintura. Analisa-se uma experi��ncia vivida pelo PEJA - Projeto de Educa����o de Jovens e Adultos da FCL ��� Unesp/Assis. Os educadores deste projeto ofereceram uma Oficina intitulada ���Arte e Educa����o: a Arte como linguagem na Educa����o de Jovens e Adultos���, destinada aos educadores da rede oficial de ensino do munic��pio de Assis (SP) e regi��o e aos alunos de cursos de Licenciatura do referido campus. Cada um dos participantes foi convidado a confeccionar um quadro, utilizando materiais diversos como os convencionais pinc��is e tintas, al��m de sementes, folhas, pedras e muita sensibilidade para discutir teoria e pr��tica pedag��gicas. A Oficina aconteceu em 2003, por ocasi��o da V Jornada de Educa����o da Unesp, com carga hor��ria total de 8 horas.

The importance of Leptospira interrogans serovars Icterohaemorrhagiae and Canicola in coastal zone and in southern fields of Rio Grande do Sul, Brazil

Funda����o de Amparo �� Pesquisa do Estado de S��o Paulo (FAPESP)

Reconfigura����o de alimentadores em sistemas de distribui����o usando uma metaheur��stica e espa��o de busca reduzido

P��s-gradua����o em Engenharia El��trica - FEIS

Algoritmo gen��tico especializado aplicado ao planejamento da expans��o de sistemas de distribui����o de energia el��trica

P��s-gradua����o em Engenharia El��trica - FEIS

Otimiza����o combinat��ria para aloca����o de fontes renov��veis em microrredes de corrente cont��nua

P��s-gradua����o em Engenharia El��trica - FEIS

Programa����o de hor��rios usando um algoritmo gen��tico especializado

P��s-gradua����o em Engenharia El��trica - FEIS

Evidence for the 125 GeV Higgs boson decaying to a pair of tau leptons

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.

Measurement of the t-channel single-top-quark production cross section and of the |V (tb)| CKM matrix element in pp collisions at root s=8 TeV

Conselho Nacional de Desenvolvimento Cient��fico e Tecnol��gico (CNPq)

Search for gravitational wave ringdowns from perturbed intermediate mass black holes in LIGO-Virgo data from 2005-2010

We report results from a search for gravitational waves produced by perturbed intermediate mass black holes ( IMBH) in data collected by LIGO and Virgo between 2005 and 2010. The search was sensitive to astrophysical sources that produced damped sinusoid gravitational wave signals, also known as ringdowns, with frequency 50 <= f(0)/Hz <= 2000 and decay timescale 0.0001 less than or similar to tau/s less than or similar to 0.1 characteristic of those produced in mergers of IMBH pairs. No significant gravitational wave candidate was detected. We report upper limits on the astrophysical coalescence rates of IMBHs with total binary mass 50 <= M/ M circle dot <= 450 and component mass ratios of either 1: 1 or 4: 1. For systems with total mass 100 <= M/M circle dot <= 150, we report a 90% confidence upper limit on the rate of binary IMBH mergers with nonspinning and equal mass components of 6.9 x 10(-8) Mpc(-3) yr(-1). We also report a rate upper limit for ringdown waveforms from perturbed IMBHs, radiating 1% of their mass as gravitational waves in the fundamental, l = m = 2, oscillation mode, that is nearly three orders of magnitude more stringent than previous results.

Methods and results of a search for gravitational waves associated with gamma-ray bursts using the GEO 600, LIGO, and Virgo detectors

In this paper we report on a search for short-duration gravitational wave bursts in the frequency range 64 Hz-1792 Hz associated with gamma-ray bursts (GRBs), using data from GEO 600 and one of the LIGO or Virgo detectors. We introduce the method of a linear search grid to analyze GRB events with large sky localization uncertainties, for example the localizations provided by the Fermi Gamma-ray Burst Monitor (GBM). Coherent searches for gravitational waves (GWs) can be computationally intensive when the GRB sky position is not well localized, due to the corrections required for the difference in arrival time between detectors. Using a linear search grid we are able to reduce the computational cost of the analysis by a factor of O(10) for GBM events. Furthermore, we demonstrate that our analysis pipeline can improve upon the sky localization of GRBs detected by the GBM, if a high-frequency GW signal is observed in coincidence. We use the method of the linear grid in a search for GWs associated with 129 GRBs observed satellite-based gamma-ray experiments between 2006 and 2011. The GRBs in our sample had not been previously analyzed for GW counterparts. A fraction of our GRB events are analyzed using data from GEO 600 while the detector was using squeezed-light states to improve its sensitivity; this is the first search for GWs using data from a squeezed-light interferometric observatory. We find no evidence for GW signals, either with any individual GRB in this sample or with the population as a whole. For each GRB we place lower bounds on the distance to the progenitor, under an assumption of a fixed GW emission energy of 10(-2)M circle dot c(2), with a median exclusion distance of 0.8 Mpc for emission at 500 Hz and 0.3 Mpc at 1 kHz. The reduced computational cost associated with a linear search grid will enable rapid searches for GWs associated with Fermi GBM events once the advanced LIGO and Virgo detectors begin operation.