1,016 research outputs found

    Estimating rBDπr_{B}^{D\pi} as an input to the determination of the CKM angle γ\gamma

    Full text link
    The interference between Cabibbo-favoured and Cabibbo-suppressed B→DπB\to D\pi decay amplitudes provides sensitivity to the CKM angle γ\gamma. The relative size of the interfering amplitudes is an important ingredient in the determination of γ\gamma. Using branching fractions from various B→DhB\to Dh decays, and the measured value for rBDKr_{B}^{DK}, the magnitude of the amplitude ratio of B+→D0π+B^+\to D^0\pi^+ and B+→Dˉ0π+B^+\to \bar{D}^0\pi^+ decays is estimated to be rBDπ=0.0053±0.0007r_{B}^{D\pi} = 0.0053 \pm 0.0007.Comment: 4 pages, 4 figure

    Properties of the Higgs-like state around 125 GeV in its decay into two photons at the CMS experiment

    Get PDF
    Results are presented of a search for the Standard Model (SM) Higgs boson decaying into two photons at the Compact Muon Solenoid (CMS) experiment housed at the Large Hadron Collider (LHC), CERN. An excess of events is observed over the background expectation with a local significance of 5.7 (lower-case sigma), where the SM expectation is 5.2 (lower-case sigma), constituting a standalone discovery of the particle first observed by the ATLAS and CMS experiments in July 2012. Measurements of the particle's signal strength, mass and couplings are presented along with an analysis of its spin. The results show a high level of compatibility with the predictions for a SM Higgs boson. The observed state's signal strength relative to the SM expectation is found to be lower-case sigma/lower-case sigma_{\mathrm{SM}}=1.14^{+0.26}_{-0.23}.Theobservedstate′smassisfoundtobe. The observed state's mass is found to be 124.72\pm 0.35$~GeV. The signal strength relative to the SM expectation when probing production mechanisms through fermionic modes only is 1.13^{+0.37}_{-0.31}, and from bosonic production modes only is 1.16^{+0.63}_{-0.57}. A spin-2 graviton, produced entirely by gluon fusion, is excluded at 94\%~C.L.~(92\% expected) and a spin-2 graviton, produced entirely by quark-antiquark annihilation, is excluded at 85\%~C.L.~(83\% expected).Open Acces

    Future prospects for exploring present day anomalies in flavour physics measurements with Belle II and LHCb

    Full text link
    A range of flavour physics observables show tensions with their corresponding Standard Model expectations: measurements of leptonic flavour-changing neutral current processes and ratios of semi-leptonic branching fractions involving different generations of leptons show deviations of the order of four standard deviations. If confirmed, either would be an intriguing sign of new physics. In this manuscript, we analyse the current experimental situation of such processes and for the first time estimate the combined impact of the future datasets of the Belle II and LHCb experiments on the present tensions with the Standard Model expectations by performing scans of the new physics contribution to the Wilson coefficients. In addition, the present day and future sensitivity of tree-level CKM parameters, which offer orthogonal tests of the Standard Model, are explored. Three benchmark points in time are chosen for a direct comparison of the estimated sensitivity between the experiments. A high complementarity between the future sensitivity achieved by the Belle II and LHCb experiments is observed due to their relative strengths and weaknesses. We estimate that all of the anomalies considered here will be either confirmed or ruled out by both experiments independently with very high significance by the end of data-taking at Belle II and the LHCb upgrade

    Prospects for searches of b → sν ν ¯ decays at FCC-ee

    Get PDF
    We investigate the physics reach and potential for the study of various decays involving a b→sνν¯ transition at the Future Circular Collider running electron-positron collisions at the Z-pole (FCC-ee). Signal and background candidates, which involve inclusive Z contributions from bb¯, cc¯ and uds final states, are simulated for a proposed multi-purpose detector. Signal candidates are selected using two Boosted Decision Tree algorithms. We determine expected relative sensitivities of 0.53%, 1.20%, 3.37% and 9.86% for the branching fractions of the B0→K∗0νν¯, Bs0→ϕνν¯, B0→KS0νν¯ and Λb0→Λνν¯ decays, respectively. In addition, we investigate the impact of detector design choices related to particle-identification and vertex resolution. The phenomenological impact of such measurements on the extraction of Standard Model and new physics parameters is also studied

    Prospects for searches of b→sννˉb \to s \nu \bar{\nu} decays at FCC-ee

    Full text link
    We investigate the physics reach and potential for the study of various decays involving a b→sννˉb \to s \nu \bar{\nu} transition at the Future Circular Collider running electron-positron collisions at the ZZ-pole (FCC-ee). Signal and background candidates, which involve inclusive ZZ contributions from bbˉb\bar{b}, ccˉc\bar{c} and udsuds final states, are simulated for a proposed multi-purpose detector. Signal candidates are selected using two Boosted Decision Tree algorithms. We determine expected relative sensitivities of 0.53%0.53\%, 1.20%1.20\%, 3.37%3.37\% and 9.86%9.86\% for the branching fractions of the B0→K∗0ννˉB^{0} \to K^{*0} \nu \bar{\nu}, Bs0→ϕννˉB^{0}_{s} \to \phi \nu \bar{\nu}, B0→KS0ννˉB^{0} \to K^{0}_{S} \nu \bar{\nu} and Λb0→Λ0ννˉ\Lambda_{b}^{0} \to \Lambda^{0} \nu \bar{\nu} decays, respectively. In addition, we investigate the impact of detector design choices related to particle-identification and vertex resolution. The phenomenological impact of such measurements on the extraction of Standard Model and new physics parameters is also studied

    Staying Connected: Alternative Transportation Use, Neighborhoods, and Social Participation Among Older Americans

    Get PDF
    BACKGROUND AND OBJECTIVES: A wealth of empirical evidence documents improved health among older adults who participate in social activities. Alternative transportation can serve as a bridge linking older adults to social activities and improving person-environment fit. RESEARCH DESIGN AND METHODS: Using Waves 1-8 of the National Health and Aging Trends Study, this research examines whether alternative transportation use is associated with participation in diverse social activities among a sample of Medicare beneficiaries aged 65 or older. Additionally, this research explores whether the effect of transportation use varies across neighborhood environments. We analyzed individual trajectories of participation in social activities by estimating 2-level growth curve models. RESULTS: The use of public transportation, paratransit, getting a ride, or walking/using wheelchair/scooter to get places was associated with participating in more types of social activities. Respondents who used alternative transportation had less steep declines in participation. The effect of getting rides and using paratransit services was more pronounced among respondents living in disordered neighborhoods. DISCUSSION AND IMPLICATIONS: This research underscores the importance of alternative transportation use and the neighborhood context for participation among older adults. Age-friendly initiatives aimed at fostering greater community engagement should think broadly about the role of multiple forms of transportation

    Developing standardized patient-based cases for communication training: lessons learned from training residents to communicate diagnostic uncertainty.

    Get PDF
    Health professions education has benefitted from standardized patient (SP) programs to develop and refine communication and interpersonal skills in trainees. Effective case design is essential to ensure an SP encounter successfully meets learning objectives that are focused on communication skills. Creative, well-designed case scenarios offer learners the opportunity to engage in complex patient encounters, while challenging them to address the personal and emotional contexts in which their patients are situated. Therefore, prior to considering the practical execution of the patient encounter, educators will first need a clear and structured strategy for writing, organizing, and developing cases. The authors reflect on lessons learned in developing standardized patient-based cases to train learners to communicate to patients during times of diagnostic uncertainty, and provide suggestions to develop a set of simulation cases that are both standardized and diverse. Key steps and workflow processes that can assist educators with case design are introduced. The authors review the need to increase awareness of and mitigate existing norms and implicit biases, while maximizing variation in patient diversity. Opportunities to leverage the breadth of emotional dispositions of the SP and the affective domain of a clinical encounter are also discussed as a means to guide future case development and maximize the value of a case for its respective learning outcomes

    I Don\u27t Have a Diagnosis for You: Preparing Medical Students to Communicate Diagnostic Uncertainty in the Emergency Department

    Get PDF
    Introduction: Diagnostic uncertainty abounds in medicine, and communication of that uncertainty is critical to the delivery of high-quality patient care. While there has been training in communicating diagnostic uncertainty directed towards residents, a gap remains in preparing medical students to understand and communicate diagnostic uncertainty. We developed a session to introduce medical students to diagnostic uncertainty and to practice communicating uncertainty using a checklist during role-play patient conversations. Methods: This virtual session was conducted for third-year medical students at the conclusion of their core clerkships. It consisted of prework, didactic lecture, peer role-play, and debriefing. The prework included reflection prompts and an interactive online module. The role-play featured a patient complaining of abdominal pain being discharged from the emergency department without a confirmed diagnosis. Students participated in the role of patient, provider, or observer. Results: Data from an anonymous postsession survey (76% response rate; 202 of 265 students) indicated that most students (82%; 152 of 185) felt more comfortable communicating diagnostic uncertainty after the session. A majority (83%; 166 of 201) indicated the session was useful, and most (81%; 149 of 184) indicated it should be included in the curriculum. Discussion: This virtual session requires few facilitators; has peer role-play, eliminating the need for standardized patients; and is adaptable for in-person teaching. As its goal was to introduce an approach to communicating diagnostic uncertainty, not achieve mastery, students were not individually assessed for proficiency using the Uncertainty Communication Checklist. Students felt the session intervention was valuable

    Simulation-based mastery learning compared to standard education for discussing diagnostic uncertainty with patients in the emergency department: a randomized controlled trial.

    Get PDF
    BACKGROUND: Diagnostic uncertainty occurs frequently in emergency medical care, with more than one-third of patients leaving the emergency department (ED) without a clear diagnosis. Despite this frequency, ED providers are not adequately trained on how to discuss diagnostic uncertainty with these patients, who often leave the ED confused and concerned. To address this training need, we developed the Uncertainty Communication Education Module (UCEM) to teach physicians how to discuss diagnostic uncertainty. The purpose of the study is to evaluate the effectiveness of the UCEM in improving physician communications. METHODS: The trial is a multicenter, two-arm randomized controlled trial designed to teach communication skills using simulation-based mastery learning (SBML). Resident emergency physicians from two training programs will be randomly assigned to immediate or delayed receipt of the two-part UCEM intervention after completing a baseline standardized patient encounter. The two UCEM components are: 1) a web-based interactive module, and 2) a smart-phone-based game. Both formats teach and reinforce communication skills for patient cases involving diagnostic uncertainty. Following baseline testing, participants in the immediate intervention arm will complete a remote deliberate practice session via a video platform and subsequently return for a second study visit to assess if they have achieved mastery. Participants in the delayed intervention arm will receive access to UCEM and remote deliberate practice after the second study visit. The primary outcome of interest is the proportion of residents in the immediate intervention arm who achieve mastery at the second study visit. DISCUSSION: Patients\u27 understanding of the care they received has implications for care quality, safety, and patient satisfaction, especially when they are discharged without a definitive diagnosis. Developing a patient-centered diagnostic uncertainty communication strategy will improve safety of acute care discharges. Although use of SBML is a resource intensive educational approach, this trial has been deliberately designed to have a low-resource, scalable intervention that would allow for widespread dissemination and uptake. TRIAL REGISTRATION: The trial was registered at clinicaltrials.gov (NCT04021771). Registration date: July 16, 2019
    • …
    corecore