Sleep bruxism in children: sleep studies correlate poorly with parental reports.

UNLABELLED: The prevalence of sleep bruxism (SB) is usually reported as highest during childhood and decreases with age. However, this is based on parental reports and self-reports in the absence of quantitative data. Moreover, although SB signs, symptoms, and cutoff criteria have been established in the adult population, they remain unassessed in the pediatric population. OBJECTIVES: This study aims to classify SB in children according to sleep variables and rhythmic masticatory muscle activity (RMMA) frequency indexes and to determine associations with objective signs and symptoms of SB in comparison with parental reports. MATERIALS AND METHODS: Thirty-two children (11.5 ± 0.3 years) recruited at the orthodontic clinic underwent a dental assessment and ambulatory sleep recording (type II). Parents responded to a validated screening questionnaire on tooth clenching and grinding. A two-step cluster analysis was performed to classify participants into RMMA frequency groups, as described subsequently, followed by one-way analysis of variance (ANOVA) to compare groups. Fisher's exact test was performed for analyzing the associations between the signs and symptoms according to RMMA. RESULTS: Three RMMA frequency groups were identified: low (n = 12), moderate-high (n = 13), and control (n = 7). Between-group comparisons for episodes per hour and bursts/hour were significant (p <0.001). No relationships were found between RMMA (presence/absence) and clinically assessed tooth wear or reports of tooth clenching or grinding or craniofacial complaints. CONCLUSIONS: RMMA frequency classification differs slightly between children and adults. No association was observed between parental reports and RMMA, suggesting the need to improve parental knowledge of children's SB.

Search for charged Higgs bosons in e+e- collisions at [Formula: see text].

A search is made for charged Higgs bosons predicted by Two-Higgs-Doublet extensions of the Standard Model (2HDM) using electron-positron collision data collected by the OPAL experiment at [Formula: see text], corresponding to an integrated luminosity of approximately 600 pb-1. Charged Higgs bosons are assumed to be pair-produced and to decay into [Formula: see text], τντ or AW±. No signal is observed. Model-independent limits on the charged Higgs-boson production cross section are derived by combining these results with previous searches at lower energies. Under the assumption [Formula: see text], motivated by general 2HDM type II models, excluded areas on the [Formula: see text] plane are presented and charged Higgs bosons are excluded up to a mass of 76.3 GeV at 95 % confidence level, independent of the branching ratio BR(H±â†’τντ ). A scan of the 2HDM type I model parameter space is performed and limits on the Higgs-boson masses [Formula: see text] and mA are presented for different choices of tanß.

Independent measurement of the total active 8B solar neutrino flux using an array of 3He proportional counters at the Sudbury Neutrino Observatory.

The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (nu_x) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54_-0.31;+0.33(stat)-0.34+0.36(syst)x10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Deltam2=7.59_-0.21;+0.19x10(-5) eV2 and theta=34.4_-1.2;+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNO's previous results.

Measurement of the total active 8B solar neutrino flux at the Sudbury Neutrino Observatory with enhanced neutral current sensitivity.

The Sudbury Neutrino Observatory has precisely determined the total active (nu(x)) 8B solar neutrino flux without assumptions about the energy dependence of the nu(e) survival probability. The measurements were made with dissolved NaCl in heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21 +/- 0.27(stat)+/-0.38(syst) x 10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of these and other solar and reactor neutrino results yields Deltam(2)=7.1(+1.2)(-0.6) x 10(-5) eV(2) and theta=32.5(+2.4)(-2.3) degrees. Maximal mixing is rejected at the equivalent of 5.4 standard deviations.

Constraints on nucleon decay via invisible modes from the Sudbury Neutrino Observatory.

Data from the Sudbury Neutrino Observatory have been used to constrain the lifetime for nucleon decay to "invisible" modes, such as n-->3nu. The analysis was based on a search for gamma rays from the deexcitation of the residual nucleus that would result from the disappearance of either a proton or neutron from 16O. A limit of tau(inv)>2 x 10(29) yr is obtained at 90% confidence for either neutron- or proton-decay modes. This is about an order of magnitude more stringent than previous constraints on invisible proton-decay modes and 400 times more stringent than similar neutron modes.