1,846 research outputs found

    Exploiting the Symmetry of the Resonator Mode to Enhance PELDOR Sensitivity.

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    Pulsed electron paramagnetic resonance (EPR) spectroscopy using microwaves at two frequencies can be employed to measure distances between pairs of paramagnets separated by up to 10 nm. The method, combined with site-directed mutagenesis, has become increasingly popular in structural biology for both its selectivity and capability of providing information not accessible through more standard methods such as nuclear magnetic resonance and X-ray crystallography. Despite these advantages, EPR distance measurements suffer from poor sensitivity. One contributing factor is technical: since 65 MHz typically separates the pump and detection frequencies, they cannot both be located at the center of the pseudo-Lorentzian microwave resonance of a single-mode resonator. To maximize the inversion efficiency, the pump pulse is usually placed at the center of the resonance, while the observer frequency is placed in the wing, with consequent reduction in sensitivity. Here, we consider an alternative configuration: by spacing pump and observer frequencies symmetrically with respect to the microwave resonance and by increasing the quality factor, valuable improvement in the signal-to-noise ratio can be obtained

    Ultimate strength of adjustable telescopic steel props according to standard EN 1065

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    The European standard EN 1065 - to which most current European production appears not to have been upgraded - addresses the design and the manufacturing of adjustable telescopic steel props, an interest bearing economic sector. The present work aims at showing an efficient strategy for the assessment of the ultimate strength of steel props according to EN 1065 in order to identify the ideal cost-performance ratio in the real life production

    Long-term outcome of everolimus treatment in transplant patients

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    Maurizio Salvadori, Elisabetta BertoniRenal Unit, Careggi University Hospital, Florence, ItalyAbstract: The authors review the use of everolimus in long-term studies both in renal and heart transplantation. The pharmacokinetic and pharmacodynamic differences between everolimus and its parent drug, sirolimus are discussed. The improved pharmacokinetic, in particular the improved bioavailability, the reduced half-time and the reduced binding to plasma protein makes everolimus the first choice among the proliferation signal inhibitors. Everolimus is given in almost all studies in association with cyclosporine, but fixed doses of this drug can cause nephrotoxicity. The first studies used everolimus and CsA in fixed doses, but later studies with reduced CsA doses revealed which revealed improved outcomes. Finally, therapeutic drug monitoring became the better choice for both drugs. Recently very high everolimus exposure allowed the use of very low CsA exposure with improvement of the worse side effects linked to the CsA standard dose. The Zeus study revealed a complete and safe CsA withdrawal, thanks to everolimus and mycophenolic acid. In heart transplantation, everolimus resulted in improved outcomes with respect to antiproliferative drugs such as mycophenolic acid and azathioprine. Along with antirejection properties, everolimus provided evidence for antiproliferative effects on several cells. This resulted in fewer viral infections (mainly CMV), anti-atherosclerotic properties (mainly important in heart transplantation, and antineoplastic effect. The latter activity resulted in lower cancer incidence in transplant patients treated by everolimus. An important piece of evidence for this activity is documented by the use of everolimus in the treatment of some cancers, including renal cancer, neuroendocrine cancers and hepatocellular cancers, also outside the field of transplantation.Keywords: everolimus, renal transplantation, heart transplantation, CNI minimization, CNI withdrawa
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