423 research outputs found

    High-m Kink/Tearing Modes in Cylindrical Geometry

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    The global ideal kink equation, for cylindrical geometry and zero beta, is simplified in the high poloidal mode number limit and used to determine the tearing stability parameter, Δ′\Delta^\prime. In the presence of a steep monotonic current gradient, Δ′\Delta^\prime becomes a function of a parameter, σ0\sigma_0, characterising the ratio of the maximum current gradient to magnetic shear, and xsx_s, characterising the separation of the resonant surface from the maximum of the current gradient. In equilibria containing a current "spike", so that there is a non-monotonic current profile, Δ′\Delta^\prime also depends on two parameters: κ\kappa, related to the ratio of the curvature of the current density at its maximum to the magnetic shear, and xsx_s, which now represents the separation of the resonance from the point of maximum current density. The relation of our results to earlier studies of tearing modes and to recent gyro-kinetic calculations of current driven instabilities, is discussed, together with potential implications for the stability of the tokamak pedestal.Comment: To appear in Plasma Physics and Controlled Fusio

    Should we perform multiparametric magnetic resonance imaging of the bladder before transurethral resection of bladder? Time to reconsider the rules

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    We would like to congratulate Ueno and colleagues [1] on their paper on diagnostic accuracy and interobserver agreement for the new Vesical Imaging-Reporting and Data System (VI-RADS) [2] for muscle-invasive bladder cancer (MIBC) in this issue of European Urology. Their report on 74 patients who underwent multiparametric magnetic resonance imaging (mpMRI) before transurethral resection of bladder tumor (TURBT) raises great interest in the RADS (Reporting and Data Systems) era. They address the questions of reproducibility and diagnostic performance of mpMRI in the setting of bladder ca (BC), in which potential applications of this imaging technique have seen constant growth in the past decades without a definitive role having been identified

    Atualização sobre o controle estratégico do carrapato-do-boi.

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    Detecção da resistência. Classe dos carrapaticidas. Ciclo biológico do carrapato R. microplus. Controle estratégico. Cuidados no controle.bitstream/CNPGC-2010/13274/1/COT123.pd

    An evaluation of urinary microRNA reveals a high sensitivity for bladder cancer

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    Background: Urinary biomarkers are needed to improve the care and reduce the cost of managing bladder cancer. Current biomarkers struggle to identify both high and low-grade cancers due to differing molecular pathways. Changes in microRNA (miR) expression are seen in urothelial carcinogenesis in a phenotype-specific manner. We hypothesised that urinary miRs reflecting low- and high-grade pathways could detect bladder cancers and overcome differences in genetic events seen within the disease. Methods: We investigated urinary samples (n ¼ 121) from patients with bladder cancer (n ¼ 68) and age-matched controls (n ¼ 53). Fifteen miRs were quantified using real-time PCR. Results: We found that miR is stable within urinary cells despite adverse handling and detected differential expression of 10 miRs from patients with cancer and controls (miRs 15a/15b/24-1/27b/100/135b/203/212/328/1224, ANOVA Po0.05). Individually, miR-1224-3p had the best individual performance with specificity, positive and negative predictive values and concordance of 83%, 83%, 75% and 77%, respectively. The combination of miRs-135b/15b/1224-3p detected bladder cancer with a high sensitivity (94.1%), sufficient specificity (51%) and was correct in 86% of patients (concordance). Conclusion: The use of this panel in patients with haematuria would have found 94% of urothelial cell carcinoma, while reducing cystoscopy rates by 26%. However, two invasive cancers (3%) would have been missed

    Surtos da mosca-dos-estábulos, Stomoxys calcitrans, em Mato Grosso do Sul: novo problema para as cadeias produtivas da carne e sucroalcooleira?

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    No presente documento é registrada a ocorrência de infestações preocupantes pela mosca-dos-estábulos, Stomoxys calcitrans L. (Diptera: Muscidae), em propriedades pecuárias próximas de usinas sucroalcooleiras na região Sul de Mato Grosso do Sul, no ano de 2009. A biologia do inseto; sua importância epidemiológica, econômica e veterinária e; possíveis alternativas de controle são apresentadas e discutidas. Entre as alternativas de controle sugere-se, em especial, o revolvimento completo duas vezes por semana do material de compostagem nas usinas e a drenagem do local onde é executada, assim como o enterrio parcial da palha pós-colheita da cana-de-açúcar com uso de cultivador. Nas propriedades pecuárias recomenda-se a limpeza de locais de criação da mosca, representado por acúmulo de dejetos de animais domésticos e ou de resíduos alimentares, especialmente em confinamentos e leiterias, dentre outras recomendações. Somente com ações integradas será possível resolver o problema e contribuir para o desenvolvimento sustentável de duas importantes cadeias produtivas do agronegócio brasileiro.bitstream/CNPGC-2010/12957/1/DOC175.pd

    Effectiveness and cost-effectiveness of prognostic markers in prostate cancer

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    This paper demonstrates how economic modelling can be used to derive estimates of the cost-effectiveness of prognostic markers in the management of clinically localised and moderately graded prostate cancer. The model uses a Markov process and is populated using published evidence and local data. The robustness of the results has been tested using sensitivity analysis. Three treatment policies of 'monitoring' (observation), radical prostatectomy, or a selection-based management policy using DNA-ploidy as an experimental marker, have been evaluated. Modelling indicates that a policy of managing these tumours utilising experimental markers has an estimated cost per quality-adjusted life year (QALY) of pound 12 068. Sensitivity analysis shows the results to be relatively sensitive to quality-of-life variables. If novel and experimental markers can achieve specificity in excess of 80%, then a policy of radical surgery for those identified as being at high risk and conservative treatment for the remainder would be both better for patients and cost-effective. The analysis suggests that a radical prostatectomy treatment policy for the moderately graded tumours (Gleason grades -7) modelled in this paper may be inferior to a conservative approach in the absence of reliable prognostic markers, being both more costly and yielding fewer QALYs

    Unsupervised machine learning of integrated health and social care data from the Macmillan Improving the Cancer Journey service in Glasgow

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    Background: Improving the Cancer Journey (ICJ) was launched in 2014 by Glasgow City Council and Macmillan Cancer Support. As part of routine service, data is collected on ICJ users including demographic and health information, results from holistic needs assessments and quality of life scores as measured by EQ-5D health status. There is also data on the number and type of referrals made and feedback from users on the overall service. By applying artificial intelligence and interactive visualization technologies to this data, we seek to improve service provision and optimize resource allocation.Method: An unsupervised machine-learning algorithm was deployed to cluster the data. The classical k-means algorithm was extended with the k-modes technique for categorical data, and the gap heuristic automatically identified the number of clusters. The resulting clusters are used to summarize complex data sets and produce three-dimensional visualizations of the data landscape. Furthermore, the traits of new ICJ clients are predicted by approximately matching their details to the nearest existing cluster center.Results: Cross-validation showed the model’s effectiveness over a wide range of traits. For example, the model can predict marital status, employment status and housing type with an accuracy between 2.4 to 4.8 times greater than random selection. One of the most interesting preliminary findings is that area deprivation (measured through Scottish Index of Multiple Deprivation-SIMD) is a better predictor of an ICJ client’s needs than primary diagnosis (cancer type).Conclusion: A key strength of this system is its ability to rapidly ingest new data on its own and derive new predictions from those data. This means the model can guide service provision by forecasting demand based on actual or hypothesized data. The aim is to provide intelligent person-centered recommendations. The machine-learning model described here is part of a prototype software tool currently under development for use by the cancer support community.Disclosure: Funded by Macmillan Cancer Support</p

    Changes in circulating microRNA levels associated with prostate cancer

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    BACKGROUND: The aim of this study was to investigate the hypothesis that changes in circulating microRNAs (miRs) represent potentially useful biomarkers for the diagnosis, staging and prediction of outcome in prostate cancer. METHODS: Real-time polymerase chain reaction analysis of 742 miRs was performed using plasma-derived circulating microvesicles of 78 prostate cancer patients and 28 normal control individuals to identify differentially quantified miRs. RESULTS: A total of 12 miRs were differentially quantified in prostate cancer patients compared with controls, including 9 in patients without metastases. In all, 11 miRs were present in significantly greater amounts in prostate cancer patients with metastases compared with those without metastases. The association of miR-141 and miR-375 with metastatic prostate cancer was confirmed using serum-derived exosomes and microvesicles in a separate cohort of patients with recurrent or non-recurrent disease following radical prostatectomy. An analysis of five selected miRs in urine samples found that miR-107 and miR-574-3p were quantified at significantly higher concentrations in the urine of men with prostate cancer compared with controls. CONCLUSION: These observations suggest that changes in miR concentration in prostate cancer patients may be identified by analysing various body fluids. Moreover, circulating miRs may be used to diagnose and stage prostate cance
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