Polysomnographic evaluation of obstructive sleep apnea syndrome in children, before and after adenotonsillectomy

Introduction: In the last years the Obstructive Sleep Apnea/Hypopnea Syndrome (OSAHS) has much interested because it has not been completed established. Many criteria defined for OSAS in adults and children are different. We know that patient's clinical story is not sufficient for the diagnosis of OSAHS. In childhood, the most common cause of OSAHS is adenotonsillar hypertrophy, clinically characterised by snoring, apnea episodes, restless sleep, mouth breathing and daytime somnolence. Aim: This study has the purpose of comprovating, by objective way, the OSAS improving in children who underwent adenotonsillectomy. Study design: Clinical prospective. Material and method: For that, 23 children, among 2 and 13 years old, with adenotonsillar hypertrophy, were analysed. After endoscopy and polysomnography, they were submitted to adenotonsillectomy. Results: The polysomnography was repeated 2 months after surgery. The polysomnographic findings were compared through statistic study. Conclusion: All the patients had an important improve after adenotonsillectomy. Only two children (8.69%) persisted with light OSAHS, but they had moderate and important OSAHS before. We concluded that OSAHS is a precise indication for adenotonsillectomy in children.Introdução: Nos últimos anos a Síndrome da Apnéia/Hipopnéia Obstrutiva do Sono (SAHOS) tem despertado muito interesse por tratar-se de uma condição não totalmente estabelecida. Muitos critérios usados para definir SAHOS em adultos e crianças são diferentes entre si. Em 1995 Sabe-se que a história clínica do paciente não era suficiente para estabelecer o diagnóstico de SAHOS. Na criança a causa mais comum de SAOS é a hipertrofia adenoamigdaliana, normalmente caracterizada clinicamente pela presença de roncos noturnos, episódios de apnéia, sono agitado, respiração bucal e hipersonolência diurna4. Objetivo: Este estudo tem o intuito de comprovar de forma objetiva a melhora da SAHOS em crianças submetidas a adenoamigdalectomia. Forma de estudo: Clínico prospectivo. Material e método: Para isso, foram avaliadas 23 crianças entre 2 e 13 anos (1999-2001), com hipertrofia adenoamigdaliana, que após nasofibroscopia e polissonografia foram submetidas a cirurgia de adenoamigdalectomia. A polissonografia foi repetida após 2 meses de pós-operatório. Foi então realizado estudo estatístico dos dados obtidos na polissonografia pré- e pós-operatória. Resultado: Observamos que todos os pacientes tiveram melhora importante após adenoamigdalectomia. Duas crianças (8,69%) persistiram com SAOS leve, que anteriormente eram de grau moderado e acentuado. Conclusão: Concluímos assim que SAOS é uma indicação precisa para cirurgia de adenoamigdalectomia em crianças.UNIFESP-EPM Disciplina de Otorrinolaringologia PediátricaUNIFESP, EPM, Disciplina de Otorrinolaringologia PediátricaSciEL

X-ray emission from the Sombrero galaxy: discrete sources

We present a study of discrete X-ray sources in and around the bulge-dominated, massive Sa galaxy, Sombrero (M104), based on new and archival Chandra observations with a total exposure of ~200 ks. With a detection limit of L_X = 1E37 erg/s and a field of view covering a galactocentric radius of ~30 kpc (11.5 arcminute), 383 sources are detected. Cross-correlation with Spitler et al.'s catalogue of Sombrero globular clusters (GCs) identified from HST/ACS observations reveals 41 X-rays sources in GCs, presumably low-mass X-ray binaries (LMXBs). We quantify the differential luminosity functions (LFs) for both the detected GC and field LMXBs, whose power-low indices (~1.1 for the GC-LF and ~1.6 for field-LF) are consistent with previous studies for elliptical galaxies. With precise sky positions of the GCs without a detected X-ray source, we further quantify, through a fluctuation analysis, the GC LF at fainter luminosities down to 1E35 erg/s. The derived index rules out a faint-end slope flatter than 1.1 at a 2 sigma significance, contrary to recent findings in several elliptical galaxies and the bulge of M31. On the other hand, the 2-6 keV unresolved emission places a tight constraint on the field LF, implying a flattened index of ~1.0 below 1E37 erg/s. We also detect 101 sources in the halo of Sombrero. The presence of these sources cannot be interpreted as galactic LMXBs whose spatial distribution empirically follows the starlight. Their number is also higher than the expected number of cosmic AGNs (52+/-11 [1 sigma]) whose surface density is constrained by deep X-ray surveys. We suggest that either the cosmic X-ray background is unusually high in the direction of Sombrero, or a distinct population of X-ray sources is present in the halo of Sombrero.Comment: 11 figures, 5 tables, ApJ in pres

Azimuthal anisotropy of charged particles at high transverse momenta in PbPb collisions at sqrt(s[NN]) = 2.76 TeV

The azimuthal anisotropy of charged particles in PbPb collisions at nucleon-nucleon center-of-mass energy of 2.76 TeV is measured with the CMS detector at the LHC over an extended transverse momentum (pt) range up to approximately 60 GeV. The data cover both the low-pt region associated with hydrodynamic flow phenomena and the high-pt region where the anisotropies may reflect the path-length dependence of parton energy loss in the created medium. The anisotropy parameter (v2) of the particles is extracted by correlating charged tracks with respect to the event-plane reconstructed by using the energy deposited in forward-angle calorimeters. For the six bins of collision centrality studied, spanning the range of 0-60% most-central events, the observed v2 values are found to first increase with pt, reaching a maximum around pt = 3 GeV, and then to gradually decrease to almost zero, with the decline persisting up to at least pt = 40 GeV over the full centrality range measured.Comment: Replaced with published version. Added journal reference and DO

Constraints on the χ_(c1) versus χ_(c2) polarizations in proton-proton collisions at √s = 8 TeV

The polarizations of promptly produced χ_(c1) and χ_(c2) mesons are studied using data collected by the CMS experiment at the LHC, in proton-proton collisions at √s=8  TeV. The χ_c states are reconstructed via their radiative decays χ_c → J/ψγ, with the photons being measured through conversions to e⁺e⁻, which allows the two states to be well resolved. The polarizations are measured in the helicity frame, through the analysis of the χ_(c2) to χ_(c1) yield ratio as a function of the polar or azimuthal angle of the positive muon emitted in the J/ψ → μ⁺μ⁻ decay, in three bins of J/ψ transverse momentum. While no differences are seen between the two states in terms of azimuthal decay angle distributions, they are observed to have significantly different polar anisotropies. The measurement favors a scenario where at least one of the two states is strongly polarized along the helicity quantization axis, in agreement with nonrelativistic quantum chromodynamics predictions. This is the first measurement of significantly polarized quarkonia produced at high transverse momentum

Search for anomalous t t-bar production in the highly-boosted all-hadronic final state

A search is presented for a massive particle, generically referred to as a Z', decaying into a t t-bar pair. The search focuses on Z' resonances that are sufficiently massive to produce highly Lorentz-boosted top quarks, which yield collimated decay products that are partially or fully merged into single jets. The analysis uses new methods to analyze jet substructure, providing suppression of the non-top multijet backgrounds. The analysis is based on a data sample of proton-proton collisions at a center-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 5 inverse femtobarns. Upper limits in the range of 1 pb are set on the product of the production cross section and branching fraction for a topcolor Z' modeled for several widths, as well as for a Randall--Sundrum Kaluza--Klein gluon. In addition, the results constrain any enhancement in t t-bar production beyond expectations of the standard model for t t-bar invariant masses larger than 1 TeV.Comment: Submitted to the Journal of High Energy Physics; this version includes a minor typo correction that will be submitted as an erratu