26 research outputs found

    Bounds on Four-Fermion Contact Interactions Induced by String Resonances

    Full text link
    Based on tree-level open-string scattering amplitudes in the low string-scale scenario, we derive the massless fermion scattering amplitudes. The amplitudes are required to reproduce those of the Standard Model at tree level in the low energy limit. We then obtain four-fermion contact interactions by expanding in inverse powers of the string scale and explore the constraints on the string scale from low energy data. The Chan-Paton factors and the string scale are treated as free parameters. We find that data from the neutral and charged current processes at HERA, Drell-Yan process at the Tevatron, and from LEP-II put lower bounds on the string scale M_S >= 0.9-1.3 TeV for typical values of the Chan-Paton factors, which are comparable to Tevatron bounds on Z' and W' masses.Comment: 13 pages, 1 ps figure, version to appear in PR

    4D Flow Cardiac MR in Primary Mitral Regurgitation

    Get PDF
    Background Four-dimensional-flow cardiac MR (4DF-MR) offers advantages in primary mitral regurgitation. The relationship between 4DF-MR-derived mitral regurgitant volume (MR-Rvol) and the post-operative left ventricular (LV) reverse remodeling has not yet been established. Purpose To ascertain if the 4DF-MR-derived MR-Rvol correlates with the LV reverse remodeling in primary mitral regurgitation. Study Type Prospective, single-center, two arm, interventional vs. nonintervention observational study. Population Forty-four patients (male N = 30; median age 68 [59–75]) with at least moderate primary mitral regurgitation; either awaiting mitral valve surgery (repair [MVr], replacement [MVR]) or undergoing “watchful waiting” (WW). Field Strength/Sequence 5 T/Balanced steady-state free precession (bSSFP) sequence/Phase contrast imaging/Multishot echo-planar imaging pulse sequence (five shots). Assessment Patients underwent transthoracic echocardiography (TTE), phase-contrast MR (PMRI), 4DF-MR and 6-minute walk test (6MWT) at baseline, and a follow-up PMRI and 6MWT at 6 months. MR-Rvol was quantified by PMRI, 4DF-MR, and TTE by one observer. The pre-operative MR-Rvol was correlated with the post-operative decrease in the LV end-diastolic volume index (LVEDVi). Statistical Tests Included Student t-test/Mann–Whitney test/Fisher's exact test, Bland–Altman plots, linear regression analysis and receiver operating characteristic curves. Statistical significance was defined as P < 0.05. Results While Bland–Altman plots demonstrated similar bias between all the modalities, the limits of agreement were narrower between 4DF-MR and PMRI (bias 15; limits of agreement −36 mL to 65 mL), than between 4DF-MR and TTE (bias −8; limits of agreement −106 mL to 90 mL) and PMRI and TTE (bias −23; limits of agreement −105 mL to 59 mL). Linear regression analysis demonstrated a significant association between the MR-Rvol and the post-operative decrease in the LVEDVi, when the MR-Rvol was quantified by PMRI and 4DF-MR, but not by TTE (P = 0.73). 4DF-MR demonstrated the best diagnostic performance for reduction in the post-operative LVEDVi with the largest area under the curve (4DF-MR 0.83; vs. PMRI 0.78; and TTE 0.51; P = 0.89). Data Conclusion This study demonstrates the potential clinical utility of 4DF-MR in the assessment of primary mitral regurgitation

    Prevalence of challenging behaviour in adults with intellectual disabilities, correlates, and association with mental health

    Get PDF
    Purpose of Review To summarise findings about the prevalence and correlates of challenging behaviour in adults with intellectual disabilities from robust research. We also describe findings on the interplay between challenging behaviour and mental health. Recent Findings Recent studies that have utilised psychometrically evaluated tools, with clear operational definitions, show similar findings on the prevalence of challenging behaviour of about 1 in every 5–6 adults known to services. We describe common correlates identified such as communication impairments, severity of intellectual disability, and living in institutional settings or congregate care. We also describe the complex and multifaceted relationship between challenging behaviour and mental health. Summary Based on recent studies, we propose a revised framework model to help understand challenging behaviour. We propose a number of areas where more research is required, particularly the development of risk tools clinicians can utilise in practice

    InfluĂȘncia da adubação verde e diferentes adubos orgĂąnicos na produção de fitomassa aĂ©rea de atroveran (Ocimum selloi Benth.) Influence of green manure and different organic manure on production of aereal phytomass of Ocimum selloi

    No full text
    Este trabalho teve por objetivo verificar o efeito de diferentes adubos orgĂąnicos em associação ou nĂŁo com adubo verde na produção de folhas de Ocimum selloi Benth., planta nativa do Brasil. O experimento foi conduzido na ĂĄrea experimental da Embrapa Meio Ambiente (CNPMA), localizado no municĂ­pio de JaguariĂșna, em duas ĂĄreas distintas, sendo uma delas submetidas anteriormente ao plantio e incorporação de adubo verde (Crotalaria juncea). Os tratamentos utilizados foram T1 - testemunha (solo sem adubação), T2 - cama de aviĂĄrio (5 kg m-2), T3 - hidrolisado de peixe (produto comercial FishfĂ©rtil - 5 mL m-2) e T4 - composto orgĂąnico (4 kg m-2). A colheita foi realizada 180 dias apĂłs o plantio, em janeiro de 2011, sendo colhidas as plantas Ășteis (quatro plantas por parcela). Avaliou-se o rendimento de fitomassa fresca e seca. O delineamento experimental adotado foi o esquema fatorial 2x4, com quatro repetiçÔes (blocos). As mĂ©dias obtidas foram submetidas Ă  anĂĄlise de variĂąncia seguida de teste de mĂ©dias (Tukey). Com base nos resultados obtidos, pode-se concluir que a cama de aviĂĄrio apresentou resultados mais satisfatĂłrios quanto Ă  produção de folhas de Ocimum selloi quando comparados aos demais tratamentos orgĂąnicos, nĂŁo se observando incremento nos resultados pela associação com o adubo verde Crotalaria juncea.<br>The aim of this work was to avail the effect of different manures in association or nor with green manure on yield of leaves of Ocimum selloi Benth. The assay was accomplished on experimental area of Embrapa Environmental (JaguariĂșna district), at two different spaces (with or without green manure Crotalaria juncea). The treatments used were T1 - witness (no manure), T2 - chicken manure (5 kg m-2), T3 - commercial product FishfĂ©rtil - 5 mL m-2) and T4 - composting (4 kg m-2). The cut was realized on 180 days after the planting (january - 2011), and were collected four plants/ plot. The yield of dried and fresh Ocimum selloi phytomass was availed. The experimental design was factorial scheme (2x4), with four repetitions. The treatment with chicken manure showed best results on Ocimum selloi leaves yield than the others treatments, but did not was influence by using Crotalaria juncea
    corecore