40 research outputs found

    Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

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    The inclusive and dijet production cross-sections have been measured for jets containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The measurements use data corresponding to an integrated luminosity of 34 pb^-1. The b-jets are identified using either a lifetime-based method, where secondary decay vertices of b-hadrons in jets are reconstructed using information from the tracking detectors, or a muon-based method where the presence of a muon is used to identify semileptonic decays of b-hadrons inside jets. The inclusive b-jet cross-section is measured as a function of transverse momentum in the range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet cross-section is measured as a function of the dijet invariant mass in the range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets and the angular variable chi in two dijet mass regions. The results are compared with next-to-leading-order QCD predictions. Good agreement is observed between the measured cross-sections and the predictions obtained using POWHEG + Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet cross-section. However, it does not reproduce the measured inclusive cross-section well, particularly for central b-jets with large transverse momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final version published in European Physical Journal

    Impairment of intellectual functions after surgery and posterior fossa irradiation in children with ependymoma is related to age and neurologic complications

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    <p>Abstract</p> <p>Background</p> <p>To investigate the neuropsychological outcome of children treated with surgery and posterior fossa irradiation for localized infratentorial ependymoma.</p> <p>Methods</p> <p>23 patients (age 0.3 – 14 years at diagnosis) who were treated with local posterior fossa irradiation (54 Gy) underwent one (4 patients) or sequential (19 patients) neuropsychologic evaluation. The last evaluation was performed at a median of 4.5 (1 to 15.5) years after RT.</p> <p>Results</p> <p>Mean last full scale IQ (FSIQ), verbal IQ (VIQ) and PIQ were 89.1, 94.0, and 86.2 respectively. All patients had difficulties with reading, and individual patients showed deficits in visuospatial, memory and attentional tasks. There was no trend for deterioration of intellectual outcome over time. All 5 children with IQ scores ≤ 75 were under the age of four at diagnosis. There was a significant association between the presence of cerebellar deficits and impaired IQ (72.0 vs 95.2, p < 0,001). The absence of hydrocephalus was an indicator of better neuropsychologic outcome (mean FSIQ of 102.6 vs 83.9, p = 0.025).</p> <p>Conclusion</p> <p>Within the evaluated cohort, intellectual functions were moderately impaired. Markedly reduced IQ scores were only seen with early disease manifestation and treatment, and postoperative neurological deficits had a strong impact on intellectual outcome.</p

    Factors associated with emotional and behavioural problems among school age children of breast cancer patients

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    To identify factors linked with emotional and behavioural problems in school age (6- to 17-year-old) children of women with breast cancer. Reports of children's emotional and behavioural problems were obtained from patient mothers, their healthy partners, the children's teacher and adolescents using the Child Behaviour Checklist and Mental Health subscale of the Child Health Questionnaire. Parents reported on their own level of depression and, for patients only, their quality of life. Family functioning was assessed using the Family Assessment Device and Cohesion subscale of the Family Environment Scale. Using a cross-sectional within groups design, assessments were obtained (N=107 families) where the patients were 3–36 months postdiagnosis. Risk of problems in children were linked with low levels of family cohesion, low affective responsiveness and parental over-involvement as reported by both child and mother. Adolescents reported family communication issues, which were associated with externalising behaviour problems. Maternal depression was related to child internalising problems, particularly in girls. Whether the mother was currently on or off chemotherapy was not associated with child problems nor was time since cancer diagnosis. These findings held across child age. Where mothers have early stage breast cancer, a substantial minority of their school-aged children have emotional and behavioural problems. Such cases are characterised by the existence of maternal depression and poor family communication, rather than by the mother's treatment status or time since diagnosis. Targeted treatments, which focus on maternal depression and family communication may benefit the children and, through improved relationships, enhance the patients' quality of life
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