974 research outputs found

    Rigorous QCD Predictions for Decays of P-Wave Quarkonia

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    Rigorous QCD predictions for decay rates of the P-wave states of heavy quarkonia are presented. They are based on a new factorization theorem which is valid to leading order in the heavy quark velocity and to all orders in the running coupling constant of QCD. The decay rates for all four P states into light hadronic or electromagnetic final states are expressed in terms of two phenomenological parameters, whose coefficients are perturbatively calculable. Logarithms of the binding energy encountered in previous perturbative calculations of P-wave decays are factored into a phenomenological parameter that is related to the probability for the heavy quark-antiquark pair to be in a color-octet S-wave state. Applying these predictions to charmonium, we use measured decay rates for the \chione and \chitwo to predict the decay rates of the \chizero and hch_c.Comment: 13 page

    Epidemiology of Contemporary Seroincident HIV Infection in the Navy and Marine Corps

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    Human Immunodeficiency Virus (HIV) infection continues at a steady rate among U.S. Sailors and Marines. This study provides the first service-specific description of HIV infection demographics. All Sailors and Marines identified as HIV infected between January 2005 and August 2010 were included. The project compared personnel and epidemiologic data, and tested reposed sera in the Department of Defense Serum Repository. This group comprised 410 Sailors and 86 Marines, predominantly men. HIV infected Marines were more likely to be foreign born than their Navy counterparts, 42% versus 10%, p \u3c 0.001. Approximately half of the patients had deployed including to the wars in Iraq or Afghanistan. Nearly half of each group was infected by the age of 25. Similar to the U.S. epidemic, Black race was over-represented. Unlike national rates, Hispanic Sailors and Marines were not over-represented. Demographics were distinct for those of specific occupational specialties. Certain ship classes carried lower incidences. Clustering of HIV infection risk occurred around deployment. The Navy and Marine Corps have different patterns of HIV infection, which may merit distinct approaches to prevention. The Navy may have unique targets for prevention efforts to include pipeline training and first assignment as well as particular occupational environments

    Further Evaluation of the Associations Between Psychopathic Traits and Symptoms of PTSD and Depression in a Nonclinical Sample

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    Examining psychopathic traits at the factor or facet level has revealed that various aspects of psychopathy may be differentially related, even in opposing directions, to important outcomes (e.g., intelligence, emotion regulation). Empirical work on relations between psychopathy and internalizing disorders, such as posttraumatic stress disorder (PTSD) and depression, has provided evidence for a positive association with antisocial traits. However, findings for the affective domain have been more equivocal. The current study (N = 732) sought to replicate past findings of the positive association of antisocial psychopathic traits with higher levels of PTSD and depressive symptoms, and to further explore associations between affective traits of psychopathy and these disorders using two measures of psychopathy. Results confirmed prior findings of a positive correlation between antisocial features and self-reported PTSD/Depression symptom severity, but they did not provide evidence for any association with affective traits. Future research using longitudinal designs is needed to begin establishing temporal ordering of the psychopathy–internalizing relationship

    The Autism Symptom Dimensions Questionnaire: Development and psychometric evaluation of a new, open-source measure of autism symptomatology

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    Aim: To describe the development and initial psychometric evaluation of a new, freely available measure, the Autism Symptom Dimensions Questionnaire (ASDQ). Method: After development and revision of an initial 33-item version, informants completed a revised 39-item version of the ASDQ on 1467 children and adolescents (aged 2-17 years), including 104 with autism spectrum disorder (ASD). Results: The initial 33-item version of the ASDQ had good reliability and construct validity. However, only four specific symptom factors were identified, potentially due to an insufficient number of items. Factor analyses of the expanded instrument identified a general ASD factor and nine specific symptom factors with good measurement invariance across demographic groups. Scales showed good-to-excellent overall and conditional reliability. Exploratory analyses of predictive validity for ASD versus neurotypical and other developmental disability diagnoses indicated good accuracy for population and at-risk contexts. Interpretation: The ASDQ is a free and psychometrically sound informant report instrument with good reliability of measurement across a continuous range of scores and preliminary evidence of predictive validity. The measure may be a useful alternative to existing autism symptom measures but further studies with comparison of clinical diagnoses using criterion-standard instruments are needed

    Mesons with Beauty and Charm: Spectroscopy

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    Applying knowledge of the interaction between heavy quarks derived from the study of ccc\overline{c} and bbb\overline{b} bound states, we calculate the spectrum of cbc\overline{b} mesons. We compute transition rates for the electromagnetic and hadronic cascades that lead from excited states to the 1S0^1\text{S}_0 ground state, and briefly consider the prospects for experimental observation of the spectrum.Comment: 32 pages + 2 uuencoded PostScript figures Fermilab-Pub-94/032-

    Mesothelin-specific CD8+ T Cell Responses Provide Evidence of In Vivo Cross-Priming by Antigen-Presenting Cells in Vaccinated Pancreatic Cancer Patients

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    Tumor-specific CD8+ T cells can potentially be activated by two distinct mechanisms of major histocompatibility complex class I–restricted antigen presentation as follows: direct presentation by tumor cells themselves or indirect presentation by professional antigen-presenting cells (APCs). However, controversy still exists as to whether indirect presentation (the cross-priming mechanism) can contribute to effective in vivo priming of tumor-specific CD8+ T cells that are capable of eradicating cancer in patients. A clinical trial of vaccination with granulocyte macrophage–colony stimulating factor–transduced pancreatic cancer lines was designed to test whether cross-presentation by locally recruited APCs can activate pancreatic tumor-specific CD8+ T cells. Previously, we reported postvaccination delayed-type hypersensitivity (DTH) responses to autologous tumor in 3 out of 14 treated patients. Mesothelin is an antigen demonstrated previously by gene expression profiling to be up-regulated in most pancreatic cancers. We report here the consistent induction of CD8+ T cell responses to multiple HLA-A2, A3, and A24-restricted mesothelin epitopes exclusively in the three patients with vaccine-induced DTH responses. Importantly, neither of the vaccinating pancreatic cancer cell lines expressed HLA-A2, A3, or A24. These results provide the first direct evidence that CD8 T cell responses can be generated via cross-presentation by an immunotherapy approach designed to recruit APCs to the vaccination site

    The Impact of the COVID-19 Pandemic on Racial Disparities in Patients Undergoing Total Shoulder Arthroplasty in the United States

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    INTRODUCTION: The purpose of this study was to assess racial disparities in total shoulder arthroplasty (TSA) in the US and to determine whether these disparities were affected by the COVID-19 pandemic. METHODS: Centers for Medicare and Medicaid Services (CMS) 100% sample was used to examine primary TSA volume from April-December from 2019-2020. Utilization was assessed for White/Black/Hispanic/Asian populations to determine if COVID-19 affected these groups differently. A regression model adjusted for age/sex/CMS-Hierarchical Condition Categories (HCC) score, dual enrollment (proxy for socioeconomic status), time fixed effects, and Core-based Statistical Area (CBSA) fixed effects was used to study difference across groups. RESULTS: In 2019, TSA volume/1000 beneficiaries was 1.51 for White and 0.57 for non-White, a 2.6-fold difference. In 2020, the rate of TSA in White patients (1.30/1000) was 2.9 times higher than non-White (0.45/1000) during the COVID-19 pandemic (P\u3c0.01). There was an overall 14% decrease in TSA volume/1000 Medicare beneficiaries in 2020; non-White patients had a larger percentage decrease in TSA volume than White (21% vs. 14%, estimated difference;8.7%,p = 0.02). Black patients experienced the most pronounced disparity with estimated difference of 10.1%,p = 0.05, compared with White patients. Similar disparities were observed when categorizing procedures into anatomic and reverse TSA, but not proximal humerus fracture. CONCLUSIONS: During the COVID-19 pandemic, overall TSA utilization decreased by 14% with White patients experiencing a decrease of 14%, and non-White patients experiencing a decrease of 21%. This trend was observed for elective TSA while disparities were less apparent for proximal humerus fracture

    Outcome of acute ST-segment elevation myocardial infarction in diabetics treated with fibrinolytic or combination reduced fibrinolytic therapy and platelet glycoprotein IIb/IIIa inhibition: Lessons from the GUSTO V trial

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    OBJECTIVES We studied the outcome of diabetics enrolled in the Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) V trial to assess whether the combination of half-dose reteplase and abciximab provides any propitious benefits over standard fibrinolytic therapy in diabetic patients. BACKGROUND Diabetics with acute ST-segment elevation myocardial infarction (MI) have a worse outcome compared with nondiabetics. Higher-risk patients are usually more likely to benefit from advances in medical therapy. METHODS We analyzed diabetic patients enrolled in the GUSTO V trial to assess the outcome of those randomized to the combination of half-dose reteplase and abciximab versus those randomized to reteplase. We also evaluated whether any differences existed in presentation and outcome of MI among the diabetics versus the nondiabetics enrolled in the study. RESULTS The trial enrolled 13,782 nondiabetics and 2,633 diabetics. Compared to nondiabetics, diabetics had a significantly higher mortality at 30 days (8.5% vs. 5.1%, p < 0.001) and at 1 year (12.7% vs. 7.5%, p < 0.001). Among the diabetic subset, no significant difference existed in the incidence of 30-day (8.8% vs. 8.2%, p = 0.52) or 1-year mortality (13.0% vs. 12.4%, p = 0.62) among patients randomized to reteplase compared to those receiving combination of abciximab and reteplase. The incidence of reinfarction (2.5% vs. 4.3%, p = 0.013), recurrent ischemia (11.8% vs. 14.9%, p = 0.017), and urgent revascularization (10.9% vs. 13.3%, p = 0.055) at seven days was lower in diabetics treated with the combination therapy. CONCLUSIONS Compared to nondiabetics, diabetics continue to have a worse outcome with MI. Although combination therapy did not provide a survival benefit, nonfatal ischemic outcomes, including reinfarction, recurrent ischemia, and urgent revascularization, were substantially reduced
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