4,048 research outputs found

    Spectral line width decrease in the solar corona: resonant energy conversion from Alfv{\'e}n to acoustic waves

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    Observations reveal an increase with height of the line width of several coronal spectral lines probably caused by outwardly propagating Alfv{\'e}n waves. However, the spectral line width sometimes shows a sudden decrease at a height 0.1-0.2 R, where the ratio of sound to Alfven speeds may approach unity. Qualitative analysis shows that the resonant energy conversion from Alfven to acoustic waves near the region of the corona where the plasma β\beta approaches unity may explain the observed spectral line width reduction.Comment: 4 pages, 3 figure

    Subset- and tissue-defined STAT5 thresholds control homeostasis and function of innate lymphoid cells

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    Innate lymphoid cells (ILCs) patrol environmental interfaces to defend against infection and protect barrier integrity. Using a genetic tuning model, we demonstrate that the signal-dependent transcription factor (TF) STAT5 is critical for accumulation of all known ILC subsets in mice and reveal a hierarchy of STAT5 dependency for populating lymphoid and nonlymphoid tissues. We apply transcriptome and genomic distribution analyses to define a STAT5 gene signature in natural killer (NK) cells, the prototypical ILC subset, and provide a systems-based molecular rationale for its key functions downstream of IL-15. We also uncover surprising features of STAT5 behavior, most notably the wholesale redistribution that occurs when NK cells shift from tonic signaling to acute cytokine-driven signaling, and genome-wide coordination with T-bet, another key TF in ILC biology. Collectively, our data position STAT5 as a central node in the TF network that instructs ILC development, homeostasis, and function and provide mechanistic insights on how it works at cellular and molecular levels

    The inter-rater reliability of the diagnosis of surgical site infection in the context of a clinical trial.

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    ObjectivesThe diagnosis of surgical site infection following endoprosthetic reconstruction for bone tumours is frequently a subjective diagnosis. Large clinical trials use blinded Central Adjudication Committees (CACs) to minimise the variability and bias associated with assessing a clinical outcome. The aim of this study was to determine the level of inter-rater and intra-rater agreement in the diagnosis of surgical site infection in the context of a clinical trial.Materials and methodsThe Prophylactic Antibiotic Regimens in Tumour Surgery (PARITY) trial CAC adjudicated 29 non-PARITY cases of lower extremity endoprosthetic reconstruction. The CAC members classified each case according to the Centers for Disease Control (CDC) criteria for surgical site infection (superficial, deep, or organ space). Combinatorial analysis was used to calculate the smallest CAC panel size required to maximise agreement. A final meeting was held to establish a consensus.ResultsFull or near consensus was reached in 20 of the 29 cases. The Fleiss kappa value was calculated as 0.44 (95% confidence interval (CI) 0.35 to 0.53), or moderate agreement. The greatest statistical agreement was observed in the outcome of no infection, 0.61 (95% CI 0.49 to 0.72, substantial agreement). Panelists reached a full consensus in 12 of 29 cases and near consensus in five of 29 cases when CDC criteria were used (superficial, deep or organ space). A stable maximum Fleiss kappa of 0.46 (95% CI 0.50 to 0.35) at CAC sizes greater than three members was obtained.ConclusionsThere is substantial agreement among the members of the PARITY CAC regarding the presence or absence of surgical site infection. Agreement on the level of infection, however, is more challenging. Additional clinical information routinely collected by the prospective PARITY trial may improve the discriminatory capacity of the CAC in the parent study for the diagnosis of infection.Cite this article: J. Nuttall, N. Evaniew, P. Thornley, A. Griffin, B. Deheshi, T. O'Shea, J. Wunder, P. Ferguson, R. L. Randall, R. Turcotte, P. Schneider, P. McKay, M. Bhandari, M. Ghert. The inter-rater reliability of the diagnosis of surgical site infection in the context of a clinical trial. Bone Joint Res 2016;5:347-352. DOI: 10.1302/2046-3758.58.BJR-2016-0036.R1
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