Influence of delay between dental bleaching with 35% hydrogen peroxide and orthodontic brackets on the bond strength at the enamel/adhesive interface

The aim of this study was to evaluate the influence of waiting time between the bleaching with 35% hydrogen peroxide and orthodontic brackets bonding on shear bond strength (SBS) in enamel. Eighty bovine teeth were randomly divided into four groups (G): G1(negative control) and G2, G3 and G4 (experimental groups). The experimental groups were submitted to bleaching. Prior to orthodontic brackets bonding to enamel the procedure was adopted different waiting times, as follows: G2 (1 day); G3 (7 days) and G4 (14 days). It was performed enamel etching (30s), washing water (30s), application of adhesive system followed by photoactivation (20s). A thin layer of composite resin was placed between the adhesive and the brackets. The applied pressure was measured by tensiometer (300N/40s). The composite resin was light-cured (40s). After 24 hours the shear test was held (0.5mm/min). To compare the SBS it was used ANOVA one-way followed by Tukey test (? = 0.05). The Adhesive Remaining Index (ARI) was analyzed using the Kruskal-Wallis test. The SBS values were significantly lower in G2 (15.51 MPa) and G3 (17.77 MPa) compared to G1 (30.14 MPa) and G4 (28.50 MPa) (p<0.05). The ARI revealed significant difference between the G3 and the other groups (p<0.05). It was concluded that the bond strength in enamel in the interfaces/adhesive system/composite resin/orthodontic brackets was more effective 14 days after the bleaching with 35% hydrogen peroxide

Validation of a cable speedometer for butterfly evaluation

Getting fast results from the evaluation of swimmers is one of the most important goals to achieve with technological development in the field. The purpose of this study was to validate a real-time velocimetric device (speedometer) through the comparison of their results with computer assisted videogrametry. The sample included 7 international level swimmers (3 females and 4 males). Each swimmer performed four 25m trials, two at 200m race pace and two at 50m race pace. For each trial, two stroke cycles were studied, resulting on a total of 28 cycles SWIMMING EVALUATION, ADVICE AND BIOFEEDBACK Rev Port Cien Desp 6(Supl.2) 201–282 237 analysed. Hip v(t) curves obtained from speedometer and videogrametry were compared, as well as the speedometer hip curve with the one of the centre of mass (CM). The higher mean correlation obtained was between vhip1 and vhip2 (0.955±0.028), followed by vhip1 with vCM (0.920±0.049). The lower correlation was vhip2 vs. vCM (0.878±0.053). It was concluded that the speedometer is a reliable, fast and interactive tool for training advice

Chemoenzymatic synthesis of (S)-Pindolol using lipases

A straightforward chemoenzymatic synthesis of (S)-Pindolol has been developed. The key step involved the enzymatic kinetic resolution of rac-2-acetoxy-1-(1H-indol-4-yloxy)-3-chloropropane with lipase from Pseudomonas fluorescens via hydrolytic process to obtain enantiomerically enriched halohydrin (2S)-1-(1H-indol-4-yloxy)-3-chloro-2-propanol (96% ee) and (2R)-2-acetoxy-1-(1H-indol-4-yloxy)-3-chloropropane (97% ee). The latter was subjected to a hydrolysis reaction catalyzed by Candida rugosa leading to (2R)-1-(1H-indol-4-yloxy)-3-chloro-2-propanol (97% ee), followed by a reaction with isopropylamine, producing (S)-Pindolol (97% ee) in quantitative yield

Population genetics of wild-type CAG repeats in the Machado-Joseph disease gene in Portugal

To gain insights on the molecular mechanisms of mutation that led to the emergence of expanded alleles in the MJD gene, by studying the behavior of wild-type alleles and testing the association of its distribution with the representation of the disease. Methods: The number of CAG motifs in the MJD gene was determined in a representative sample of 1000 unrelated individuals. Associations between the repeat size and the epidemiological representation of MJD were tested. Results: The allelic profi le of the total sample was in the normal range (13–41 repeats), with mode (CAG) 23 . No intermediate alleles were present. Allelic size distribution showed a negative skew. The correlation between the epidemiological representation of MJD in each district and the frequency of small, medium and large normal alleles was not signifi cant. Further correlations performed grouping the districts also failed to produce signifi cant results. Conclusions: The absence of association between the size of the repeats and the representation of MJD demonstrates that prevalence is not an indirect refl ection of the frequency of large normal alleles. Globally the results obtained are in accordance with a model that postulates the occurrence of a few mutations on the basis of most of the MJD cases worldwide

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

Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC

Measurements of inclusive jet suppression in heavy ion collisions at the LHC provide direct sensitivity to the physics of jet quenching. In a sample of lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the anti-kt algorithm with values for the distance parameter that determines the nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp. Jet production is found to be suppressed by approximately a factor of two in the 10% most central collisions relative to peripheral collisions. Rcp varies smoothly with centrality as characterized by the number of participating nucleons. The observed suppression is only weakly dependent on jet radius and transverse momentum. These results provide the first direct measurement of inclusive jet suppression in heavy ion collisions and complement previous measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables, submitted to Physics Letters B. All figures including auxiliary figures are available at http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02