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A feasibility clinical study was conducted for the transcatheter occlusion of large ostium secundum atrial septal defects with the centering buttoned device. The centering buttoned device is a modification of the regular buttoned device in which a centering counter-occluder is sutured at the central 40% portion of the occluder. During centering it is stretched, forming a parachute-shaped structure and pulling the occluder over the center of the defect. During buttoning, the counter-occluder forms a double figure eight, opposing the right atrial side of the atrial septum. Occlusion was performed in 12 patients aged 6 to 56 years. All had been rejected for transcatheter occlusion by the regular buttoned device, because of either their defect size or the lack of adequate septal rim. The defect size varied between 23 and 31 mm, and the device size varied between 45 and 60 mm. Nine had immediate effective occlusions of their defects and three residual shunts. One patient with unbuttoning had hemolysis at 2 weeks and underwent surgery. Early results of the transcatheter occlusion of large atrial septal defects are promising, and larger clinical trials are justified.  相似文献   
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Short-term (< 60 min) internalization fluxes (J(int)) by the green alga Chlamydomonas reinhardtii were measured in the presence of a variety of ligands forming hydrophilic (citric, diglycolic, or nitrilotriacetic acids), amphiphilic (Suwannee River fulvic and humic acids), and hydrophobic (oxine, diethyldithiocarbamate) Ni complexes. Free nickel concentrations, ranging from 10(-10) to 10(-3) M, were evaluated by thermodynamic modeling and by a resin exchange technique. Ni internalization appeared to occur via a single transport site that was characterized by a conditional stability constant (pH 6.0, I = 10(-2) M) of 10(5.1) M(-1). In the presence of humic substances, Ni uptake could be quantitatively predicted on the basis of Ni2+ concentrations for two algae: C. reinhardtii and Chlorella kesslerii. In the presence of the hydrophobic ligands, an increase in permeability was observed due to the formation of neutral, lipophilic complexes.  相似文献   
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Blade condition monitoring systems with fiber‐optic sensors attract much attention because they are resistant to lightning strikes, a major issue with increasing blade lengths. However, fiber‐optic sensor systems are more complex and more expensive than their electronic counterparts. We describe a new blade condition monitoring system, which combines the lightning safety of optical fibers with the reliability and cost‐effectiveness of electronic sensors. The optical fibers transport data from the blades to the hub, and in addition, they provide the electrical power for operating the sensor units in the blades. To achieve full protection against lightning‐induced electromagnetic fields, an appropriate shielding of the sensor units is required. We present results on the reliability of a newly developed prototype based on optically powered sensors. In a field trial, the unit monitored successfully the blade vibrations of a 1.5 MW wind turbine for a period of 23 months. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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Colloidal organic matter from wastewater treatment plants was characterized and examined with respect to its role in metal distribution by using tangential flow ultrafiltration, liquid chromatography coupled with organic carbon and UV detectors, and an asymmetrical flow field-flow fractionation (AFlFFF) multidetection platform. Results revealed that a humic-like fraction of low aromaticity with an average molar mass ranging from 1600 to 2600 Da was the main colloidal component. High molar mass fractions (HMM), with molar mass ranges between 20 and 200 kDa, were present in lower proportions. Ag, Cd, Cu, Cr, Mn and Zn were found mainly in the dissolved phase (<0.45 μm) and their distribution between colloidal and truly dissolved fractions was strongly influenced by the distribution of dissolved organic carbon. AFlFFF coupled to ICP-MS showed that Ag, Cd, Cu, Cr, Mn and Zn associate to the low molar mass fraction of the colloidal pool, whereas Al, Fe and Pb were equally bound to low and high molar mass fractions.  相似文献   
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A new version of the PROGRA2 instrument, dedicated to measuring the polarization phase function of various kinds of solid particles, allows obtaining maps of polarization and brightness with a spatial resolution of a few tens of micrometers. The measurements are conducted in microgravity during parabolic flights to ensure random distribution and orientation of the particles. The results of the first two sessions are presented. Comparison between measurements and Mie theory modeling for glass spheres shows that the instrument works well and that accurate results can be obtained even at small phase angles. Results for irregularly shaped particles are also presented.  相似文献   
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Datenschutz als Bildungsaufgabe und -inhalt setzt Wissen darüber voraus, was privat und was ?ffentlich ist, wie dies abgegrenzt wird und in welchem Verh?ltnis das Private und das ?ffentliche zueinander stehen. Da beides nicht einfach vorgefunden, sondern formuliert werden muss und dies im besonderen Aufgabe des Rechts ist, ist Rechtskompetenz Voraussetzung für wirksamen Datenschutz als Selbstschutz.  相似文献   
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Zusammenfassung  Die nachhaltige Weiterentwicklung eines grossen Informatiksystemes ist aufgrund der schwierigen technischen und kommerziellen Randbedingungen eine sehr anspruchsvolle Aufgabe. Einerseits haben diese Informatiksysteme eine Komplexit?t erreicht, deren Folgen immer schwieriger zu beherrschen sind. Andererseits muss ein kontinuierlicher Fluss von neuen Gesch?ftsanforderungen unter hohem Zeit- und Kostendruck implementiert werden. Dabei müssen die Informatiksysteme zu jeder Zeit verfügbar, stabil, verl?sslich und sicher bleiben sowie Effizienz und Wirtschaftlichkeit gew?hrleisten. Damit das IT-Management diese zentrale Aufgabe erfüllen kann, muss eine wirksame Evolutionsstrategie formuliert und umgesetzt werden. Credit Suisse hat für sich die Evolutionsstrategie ,,Managed Evolution“ definiert und implementiert. Dieser Beitrag erkl?rt die Managed Evolution, einen Teil der Umsetzungsinstrumente und die bis heute erreichten Resultate. Diese zeigen messbar, dass die Managed Evolution die erwarteten Erfolge liefert.  相似文献   
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