MR imaging findings in Xp21.2 duplication syndrome

Xp21.2 duplication syndrome is a rare genetic disorder of undetermined prevalence and clinical relevance. As the use of chromosomal microarray has become first line for the work-up of childhood developmental delay, more gene deletions and duplications have been recognized. To the best of our knowledge, the imaging findings of Xp21.2 duplication syndrome have not been reported. We report a case of a 33 month-old male referred for developmental delay that was found to have an Xp21.2 duplication containing IL1RAPL1 and multiple midline brain malformations

Measurement of the Bs0-Bs0 oscillation frequency δms in Bs0→Ds-(3)π decays

The Bs0-Bs0 oscillation frequency δms is measured with 36 pb-1 of data collected in pp collisions at s=7TeV by the LHCb experiment at the Large Hadron Collider. A total of 1381 Bs0→Ds-π+ and Bs0→Ds-π+π-π + signal decays are reconstructed, with average decay time resolutions of 44 fs and 36 fs, respectively. An oscillation signal with a statistical significance of 4.6σ is observed. The measured oscillation frequency is δm s=17.63±0.11(stat)±0.02(syst)ps -1

Using a coproduced educational workshop to change the focus of verbal instructions delivered by professional youth soccer coaches: a case study

Background: The predominant instructional method utilised by soccer coaches are verbal instructions that occur whilst (during) players are executing soccer-skill. However, little is known on the specificity of the information contained within. These verbal instructions can guide the learner to either the performance characteristics of a movement (internal focus) or the intended movement effects (external), with the latter known to facilitate superior motor performance, retention, and transfer. // Purpose: The aims in the present study were to quantify the focus of concurrent verbal instructions utilised by professional youth soccer coaches during drill-based (i.e. isolated) practice activities, and to modulate how these instructions are delivered in coaching sessions following the engagement in a coproduced evidence-based educational workshop. // Method: Systematic observation was used pre and post the workshop to quantify the nature of verbal instructions delivered by 5 male coaches (31–47 years of age with 4–24 years of coaching experience) across 34 sessions with players from 8 to 13 years of age. For instructions provided during (concurrent) action-execution, we further quantified whether these instructions were focused on motor performance characteristics (internal) or the intended movement outcome effects (external) using criteria outlined in the revised Arizona State University Observation Instrument. To facilitate behaviour change, all coaches engaged in an educational workshop led by skill acquisition specialists (SAS). The workshop was designed so that educational material related to the principles of skill acquisition, and motor control and learning, were presented using a pedagogical delivery method containing verbal information, data presented in illustrations, and videos. In addition, the results that quantified coaching behaviour during the pre-workshop systematic observation period were presented to coaches as quantitative feedback. To guide the coaches to appraise the quantitative feedback in relation to the delivered educational material, the SAS built an educational environment that encouraged discussion opportunities for coaches to compare and appraise feedback with other coaches and process the feedback in relation to data and concepts regarding skill acquisition. // Results and findings: The pre-workshop systematic observation data indicated that coaches delivered significantly more (64%) verbal instructions whilst (concurrently) players were executing motor skills, compared to before (15%) or after (21%). Within concurrent feedback, coaches used instructions that had a more internal, compared to external focus of attention. Post-workshop data indicated the coaches significantly changed the utilisation of instructions using a greater proportion of external focus. The data confirms coaches deliver a greater proportion of concurrent verbal instructions during coaching sessions focused training drill-based activities, but engaging in an educational workshop coaches modulated the focus of these instructions from internal to external, indicating behaviour change and an opportunity to facilitate skill acquisition in soccer academy players

Absolute luminosity measurements with the LHCb detector at the LHC

Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. Using data taken in 2010, LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In addition to the classic ''van der Meer scan'' method a novel technique has been developed which makes use of direct imaging of the individual beams using beam-gas and beam-beam interactions. This beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. The results of the two methods have comparable precision and are in good agreement. Combining the two methods, an overal precision of 3.5% in the absolute luminosity determination is reached. The techniques used to transport the absolute luminosity calibration to the full 2010 data-taking period are presented

A model-independent Dalitz plot analysis of B±→DK± with D→K0Sh+h− (h=π,K) decays and constraints on the CKM angle γ

A binned Dalitz plot analysis of B ±→DK ± decays, with D→KS0π+π- and D→KS0K+K-, is performed to measure the CP-violating observables x ± and y ± which are sensitive to the CKM angle γ. The analysis exploits 1.0 fb -1 of data collected by the LHCb experiment. The study makes no model-based assumption on the variation of the strong phase of the D decay amplitude over the Dalitz plot, but uses measurements of this quantity from CLEO-c as input. The values of the parameters are found to be x -=(0.0±4.3±1.5±0.6)×10 -2, y -=(2.7±5.2±0.8±2.3)×10 -2, x +=(-10.3±4.5±1.8±1.4)×10 -2 and y +=(-0.9±3.7±0.8±3.0)×10 -2. The first, second, and third uncertainties are the statistical, the experimental systematic, and the error associated with the precision of the strong-phase parameters measured at CLEO-c, respectively. These results correspond to γ=(44-38+43)°, with a second solution at γ→γ+180°, and r B=0.07±0.04, where r B is the ratio between the suppressed and favoured B decay amplitudes

First observation of the decay B0s→ϕK∗0

The first observation of the decay B0s→ϕK∗0 is reported. The analysis is based on a data sample corresponding to an integrated luminosity of 1.0 fb−1 of pp collisions at s√=7 TeV, collected with the LHCb detector. A yield of 30 ± 6 B0s→(K+K−)(K−π+) decays is found in the mass windows 1012.5 < M (K + K −) < 1026.5 MeV/c 2 and 746 < M(K − π +) < 1046 MeV/c 2. The signal yield is found to be dominated by B0s→ϕK∗0 decays, and the corresponding branching fraction is measured to be B(B0s→ϕK∗0) = (1.10 ± 0.24 (stat) ± 0.14 (syst) ± 0.08 (f d /f s )) × 10−6, where the uncertainties are statistical, systematic and from the ratio of fragmentation fractions f d /f s which accounts for the different production rate of B 0 and B0s mesons. The significance of B0s→ϕK∗0 signal is 6.1 standard deviations. The fraction of longitudinal polarization in B0s→ϕK∗0 decays is found to be f 0 = 0.51 ± 0.15 (stat) ± 0.07 (syst)

Observation of the suppressed ADS modes B± → [π±K-/+ π+π-]D K± and B± → [π± K-/+π+π-]Dπ±

An analysis of and B± → DK± and B± → Dπ± decays is presented where the D meson is reconstructed in the four-body final state K± π-/+π+π-. Using LHCb data corresponding to an integrated luminosity of 1.0 fb-1, first observations are made of the suppressed ADS modes B± →[π± K-/+π+π-]DK± and B± → [π± K-/+π+π-]Dπ± with a significance of 5.1 sigma and greater than 10 sigma, respectively. Measurements of CP asymmetries and CP-conserving ratios of partial widths from this family of decays are also performed. The magnitude of the ratio between the suppressed and favoured B± → DK ± amplitudes is determined to be rKB = 0.097 ± 0.011

First evidence of direct CP violation in charmless two-body decays of Bs0 mesons

Using a data sample corresponding to an integrated luminosity of 0.35  fb-1 collected by LHCb in 2011, we report the first evidence of CP violation in the decays of Bs0 mesons to K±π∓ pairs, ACP(Bs0→Kπ)= 0.27±0.08(stat)±0.02(syst), with a significance of 3.3σ. Furthermore, we report the most precise measurement of CP violation in the decays of B0 mesons to K±π∓ pairs, ACP(B0→Kπ)=-0.088±0.011(stat)±0.008(syst), with a significance exceeding 6σ

Measurement of the resonant and CP components in B¯ 0 → J=ψπþπ− decays

The resonant structure of the reaction B¯0→J/ψπ+π− is studied using data from 3  fb−1 of integrated luminosity collected by the LHCb experiment, one third at 7 TeV center-of-mass energy and the remainder at 8 TeV. The invariant mass of the π+π− pair and three decay angular distributions are used to determine the fractions of the resonant and nonresonant components. Six interfering π+π− states, ρ(770), f0(500), f2(1270), ρ(1450), ω(782) and ρ(1700), are required to give a good description of invariant mass spectra and decay angular distributions. The positive and negative charge parity fractions of each of the resonant final states are determined. The f0(980) meson is not seen and the upper limit on its presence, compared with the observed f0(500) rate, is inconsistent with a model where these scalar mesons are formed from two quarks and two antiquarks (tetraquarks) at the eight standard deviation level. In the qq¯ model, the absolute value of the mixing angle between the f0(980) and the f0(500) scalar mesons is limited to be less than 17° at 90% confidence level

Measurement of CP asymmetry in D 0 → K - K + and D 0 → π - π decays

Time-integrated CP asymmetries in D 0 decays to the final states K - K + and π - π + are measured using proton-proton collisions corresponding to 3fb-1 of integrated luminosity collected at centre-of-mass energies of 7 TeV and 8 TeV. The D 0 mesons are produced in semileptonic b-hadron decays, where the charge of the accompanying muon is used to determine the initial flavour of the charm meson. The difference in CP asymmetries between the two final states is measured to be Δ ACP = ACP (K- K +) ACP (π- π+) = (+ 0.14 ± 0.16 (stat) ± 0.08 (syst)) %. A measurement of A CP (K - K +) is obtained assuming negligible CP violation in charm mixing and in Cabibbo-favoured D decays. It is found to be ACP (K- K+) = (- 0.06 ± 0.15 (stat) ± 0.10 (syst)) %, where the correlation coefficient between ΔA CP and A CP (K - K +) is ρ = 0.28. By combining these results, the CP asymmetry in the D 0 → π - π + channel is A CP (π - π +) = (-0.20 ± 0.19 (stat) ± 0.10 (syst))%