1,500 research outputs found

    Three-Body approach to the K^- d Scattering Length in Particle Basis

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    We report on the first calculation of the scattering length A_{K^-d} based on a relativistic three-body approach where the two-body input amplitudes coupled to the Kbar N channels have been obtained with the chiral SU(3) constraint, but with isospin symmetry breaking effects taken into account. Results are compared with a recent calculation applying a similar set of two-body amplitudes,based on the fixed center approximation, considered as a good approximation for a loosely bound target, and for which we find significant deviations from the exact three-body results. Effects of the hyperon-nucleon interaction, and deuteron DD-wave component are also evaluated.Comment: 5 pages, Submitted to Phys. Rev.

    Chiral unitary approach to the K^- deuteron scattering length

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    Starting from a recent model where the Kbar N amplitudes are evaluated from the chiral Lagrangians using a coupled channel unitary method, we evaluate here the scattering length for K^- deuteron scattering. We find that the double scattering contribution is very large compared to the impulse approximation and that the charge exchange contribution of this rescattering is as large as the sequential K^- scattering on the two nucleons. Higher order rescattering corrections are evaluated using coupled channels with K^- and Kbar^0 within the integral form of the fixed centre approximation to the Faddeev equations. The higher order corrections involving intermediate pions and hyperons are found negligible.Comment: 16 pages, 4 figures, revised version to appear in Nucl. Phys.

    Nebivolol might be Beneficial in Osteoporosis Treatment: A Hypothesis

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    Nebivolol is a β-blocker that is highly selective for β1-adrenergic receptors with vasodilating properties. This property can be attributed to an endothelial release of nitric oxide (NO). It has been reported that nebivolol also reduces intracellular oxidative stress. There are some studies conducted in humans and animal models which have shown that NO is an important regulator of bone metabolism. However, oxidative stress and antioxidant systems may play important roles in the pathogenesis of osteoporosis. In this paper, we hypothesized that nebivolol may have beneficial effects via nitric oxide and antioxidant action in osteoporosis treatment

    Rising Annual Costs of Dizziness Presentations to U.S. Emergency Departments

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    Objectives Dizziness and vertigo account for roughly 4% of chief symptoms in the emergency department ( ED ). Little is known about the aggregate costs of ED evaluations for these patients. The authors sought to estimate the annual national costs associated with ED visits for dizziness. Methods This cost study of adult U.S. ED visits presenting with dizziness or vertigo combined public‐use ED visit data (1995 to 2009) from the National Hospital Ambulatory Medical Care Survey ( NHAMCS ) and cost data (2003 to 2008) from the Medical Expenditure Panel Survey ( MEPS ). We calculated total visits, test utilization, and ED diagnoses from NHAMCS . Diagnosis groups were defined using the Healthcare Cost and Utilization Project's Clinical Classifications Software ( HCUP ‐ CCS ). Total visits and the proportion undergoing neuroimaging for future years were extrapolated using an autoregressive forecasting model. The average ED visit cost‐per‐diagnosis‐group from MEPS were calculated, adjusting to 2011 dollars using the Hospital Personal Health Care Expenditures price index. An overall weighted mean across the diagnostic groups was used to estimate total national costs. Year 2011 data are reported in 2011 dollars. Results The estimated number of 2011 US ED visits for dizziness or vertigo was 3.9 million (95% confidence interval [ CI ] = 3.6 to 4.2 million). The proportion undergoing diagnostic imaging by computed tomography ( CT ), magnetic resonance imaging ( MRI ), or both in 2011 was estimated to be 39.9% (39.4% CT , 2.3% MRI ). The mean per‐ ED ‐dizziness‐visit cost was 1,004in2011dollars.Thetotalextrapolated2011nationalcostswere1,004 in 2011 dollars. The total extrapolated 2011 national costs were 3.9 billion. HCUP ‐ CCS key diagnostic groups for those presenting with dizziness and vertigo included the following (fraction of dizziness visits, cost‐per‐ ED ‐visit, attributable annual national costs): otologic/vestibular (25.7%; 768;768; 757 million), cardiovascular (16.5%, 1,489;1,489; 941 million), and cerebrovascular (3.1%; 1059;1059; 127 million). Neuroimaging was estimated to account for about 12% of the total costs for dizziness visits in 2011 ( CT scans 360million,MRIscans360 million, MRI scans 110 million). Conclusions Total U.S. national costs for patients presenting with dizziness to the ED are substantial and are estimated to now exceed $4 billion per year (about 4% of total ED costs). Rising costs over time appear to reflect the rising prevalence of ED visits for dizziness and increased rates of imaging use. Future economic studies should focus on the specific breakdown of total costs, emphasizing areas of high cost and use that might be safely reduced. Resumen Incremento Anual de los Costes de las Atenciones por Mareo en los Servicios de Urgencias de Estados Unidos Objectivos El mareo y el vértigo suman aproximadamente el 4% de los motivos de consulta en el servicio de urgencias ( SU ). Se conoce poco sobre los costes globales de las evaluaciones del SU en estos pacientes. Se buscó estimar los costes anuales nacionales asociados con las visitas al SU por mareo. Metodología Este estudio de costes de visitas al SU de adultos norteamericanos que acudieron con mareo o vértigo combinó los datos públicos de las visitas a los SU (1995 a 2009) recogidos por el National Hospital Ambulatory Medical Care Survey ( NHAMCS ) y los costes (2003 a 2008) recogidos por el Medical Expenditure Panel Survey ( MEPS ). Se calcularon el total de visitas, el uso de pruebas diagnósticas y los diagnósticos del SU del NHAMCS . Los grupos diagnósticos se definieron según el Healthcare Cost and Utilization Project's Clinical Classifications Software ( HCUP ‐ CCS ). Los datos del año 2011 se documentaron en dólares de 2011. El total de visitas y la proporción de neuroimagen llevada a cabo en los futuros años se extrapoló usando un modelo predictivo autorregresivo. La media del coste por visita al SU por grupo diagnóstico del MEPS se calculó, ajustándose a dólares de 2011, mediante el índice de precios de los Hospital Personal Health Care Expenditures. Se utilizó una media ponderada global entre los grupos diagnósticos para estimar los costes totales nacionales. Resultados El número de visitas al SU en Estados Unidos en 2011 por mareo o vértigo fue de 3,9 millones ( IC 95% = 3,6 a 4,2 millones). El porcentaje de pruebas diagnósticas de imagen llevadas a cabo por tomografía computarizada ( TC ), resonancia magnética ( RM ) o ambas en 2011 se estimó en un 39,9% (39,4% TC , 2,3% RM ). La media de coste por visita al SU por mareo fue de 1.004 dólares de 2011. Los costes totales, extrapolados para todo el país, fueron de 3.900 millones de dólares. Los grupos diagnósticos HCUP ‐ CCS para aquéllos que presentaron mareo o vértigo incluyeron los siguientes (proporción de visitas por mareo; coste por visita al SU ; costes anuales nacionales atribuibles): otológico/vestibular (25,7%; 768 dólares; 757 millones de dólares), cardiovascular (16,5%, 1.489 dólares; 941 millones de dólares) y cerebrovascular (3,1%; 1.059 dólares; 127 millones de dólares). Se estimó una suma en la neuroimagen del 12% del total de costes para las visitas por mareo en 2011 (360 millones de dólares para la TC y 110 millones de dólares para la RM ). Conclusiones Los costes totales en Estados Unidos para los pacientes que acuden por mareo al SU son sustanciales, y se estima que sobrepasan en estos momentos los 4.000 millones de dólares por año (aproximadamente un 4% de los costes totales del SU ). El incremento de los costes con el paso del tiempo parece reflejar el crecimiento de la prevalencia de las visitas al SU por mareo y el aumento de porcentajes de utilización de la neuroimagen. Futuros estudios económicos deberían centrarse en el desglose de los costes totales, y hacer énfasis en las áreas de alto uso y coste que pueden ser reducidas sin riesgo.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/99059/1/acem12168.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/99059/2/acem12168-sup-0001-DataSupplementS1.pd

    Improving the value of public RNA-seq expression data by phenotype prediction.

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    Publicly available genomic data are a valuable resource for studying normal human variation and disease, but these data are often not well labeled or annotated. The lack of phenotype information for public genomic data severely limits their utility for addressing targeted biological questions. We develop an in silico phenotyping approach for predicting critical missing annotation directly from genomic measurements using well-annotated genomic and phenotypic data produced by consortia like TCGA and GTEx as training data. We apply in silico phenotyping to a set of 70 000 RNA-seq samples we recently processed on a common pipeline as part of the recount2 project. We use gene expression data to build and evaluate predictors for both biological phenotypes (sex, tissue, sample source) and experimental conditions (sequencing strategy). We demonstrate how these predictions can be used to study cross-sample properties of public genomic data, select genomic projects with specific characteristics, and perform downstream analyses using predicted phenotypes. The methods to perform phenotype prediction are available in the phenopredict R package and the predictions for recount2 are available from the recount R package. With data and phenotype information available for 70,000 human samples, expression data is available for use on a scale that was not previously feasible

    A new perspective on the Faddeev equations and the KˉNN\bar{K}NN system from chiral dynamics and unitarity in coupled channels

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    We review recent work concerning the KˉN\bar{K}N interaction and Faddeev equations with chiral dynamics which allow us to look at the KˉNN\bar{K}NN from a different perspective and pay attention to problems that have been posed in previous studies on the subject. We show results which provide extra experimental evidence on the existence of two Λ(1405)\Lambda(1405) states. We then show the findings of a recent approach to Faddeev equations using chiral unitary dynamics, where an explicit cancellation of the two body off shell amplitude with three body forces stemming from the same chiral Lagrangians takes place. This removal of the unphysical off shell part of the amplitudes is most welcome and renders the approach unambiguous, showing that only on shell two body amplitudes need to be used. With this information in mind we use an approximation to the Faddeev equations within the fixed center approximation to study the KˉNN\bar{K}NN system, providing answers within this approximation to questions that have been brought before and evaluating binding energies and widths of this three body system. As a novelty with respect to recent work on the topic we find a bound state of the system with spin S=1, like a bound state of Kˉ\bar{K}-deuteron, less bound that the one of S=0, where all recent efforts have been devoted. The width is relatively large in this case, suggesting problems in a possible experimental observation.Comment: 18 pages, 7 figures, one misprint corrected, Nuclear Physics A in pres

    Short-Term Outcome of Combined Corticosteriod and Local Anaestetic Therapy with Home-Based Exercıse Programme in Painful Shoulder Conditions

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    Purpose: The aim of this study was to evaluate the efficacy of combined local corticosteroid and anaestethic therapy with home exercise programme in the treatment of painful shoulder conditions. Methods: 40 mg Depomedrol® (methylprednisolone acetate) + 120 mg Citanest® (procaine hydrochloride) were parenterally administered into the subacromial region of 28 patients (17 female, mean age: 48 years; 11 male, mean age: 52 years) from a group of patients who have been suffering from shoulder pain for a period of at least two months and had received no benefit from previous treatments. Simultaneously, they were placed on a home-based shoulder exercise programme. The patients were seen two months later and questioned about their conditions. The data were evaluated together with clinical findings based on the range of motion (ROM) of the shoulder. Results: Twenty of 28 patients (71.42%) reported complete relief from pain, 5 patients or 17.85% stated that they had only partial relief of pain, and 3 patients (10.71%) said that the level of pain remained essentially the same. Nineteen of 28 patients (67.85%) had good to excellent ROM while 3 (10.71%) still manifested poor ROM. Conclusion: Local corticosteroid plus local anaestethic therapy together with home exercise programme was found to be an economic, effective and safe short-term treatment in the management of painful shoulder conditions arising from certain disorders. Keywords: Painful shoulder, Local corticosteroid, Local anaesthetic, Home exercise programe, Range of motion.Tropical Journal of Pharmaceutical Research Vol. 7(4) 2008: pp. 1123-112

    On the SigmaN cusp in the pp -> pK+Lambda reaction

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    Measurements of the pppK+Λpp \to pK^+\Lambda reaction at TpT_p = 2.28 GeV have been carried out at COSY-TOF. In addition to the Λp\Lambda p FSI and NN^* resonance excitation effects a pronounced narrow structure is observed in the Dalitz plot and in its projection on the pΛp\Lambda-invariant mass. The structure appears at the pppp \to NK+ΣK^+\Sigma threshold and is interpreted as Σ\SigmaN cusp effect. The observed width of 20 MeV/c2c^2 is substantially broader than anticipated from previous inclusive measurements. Angular distributions of this cusp structure are shown to be dissimilar to those in the residual pK+ΛpK^+\Lambda channel, but similar to those observed in the pK+Σ0pK^+\Sigma^0 channel
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