35 research outputs found
Electrostatic potential in a superconductor
The electrostatic potential in a superconductor is studied. To this end
Bardeen's extension of the Ginzburg-Landau theory to low temperatures is used
to derive three Ginzburg-Landau equations - the Maxwell equation for the vector
potential, the Schroedinger equation for the wave function and the Poisson
equation for the electrostatic potential. The electrostatic and the
thermodynamic potential compensate each other to a great extent resulting into
an effective potential acting on the superconducting condensate. For the
Abrikosov vortex lattice in Niobium, numerical solutions are presented and the
different contributions to the electrostatic potential and the related charge
distribution are discussed.Comment: 19 pages, 11 figure
Automated plasmapheresis compared with other plasma collection methods in the horse
The purpose of this study was to evaluate plasmapheresis as a method for plasma extraction in comparison with centrifugation or gravity sedimentation. The study was designed as a cross over trial with six Freiberger horses undergoing plasma donation by plasmapheresis followed by whole-blood donation and subsequent plasma production 4 weeks later. Automated plasmapheresis and whole-blood donation were well tolerated in all horses. The plasmapheresis method achieved an almost complete removal of erythrocytes and leucocytes from plasma at all flow rates. After blood bag centrifugation, significantly more erythrocytes (P 0.05). However, the activity of factor VIII was significantly lower 24 h after gravity sedimentation of blood than activity prior to blood collection (P < 0.01). In conclusion, automated plasmapheresis is the method of choice for the production of high quality equine plasma
Integrated capillary electrophoresis on flexible silicone microdevices: analysis of DNA restriction fragments and detection of single DNA molecules on microchips.
Microchips for integrated capillary electrophoresis systems were produced by molding a poly(dimethylsiloxane) (PDMS) silicone elastomer against a microfabricated master. The good adhesion of the PDMS devices on clean planar surfaces allows for a simple and inexpensive generation of networks of sealed microchannels, thus removing the constraints of elaborate bonding procedures. The performance of the devices is demonstrated with both fast separations of φX-174/HaeIII DNA restriction fragments labeled with the intercalating dye YOYO-1 and fluorescently labeled peptides. Detection limits in the order of a few zeptomoles (10(-)(21) mol) have been achieved for each injected DNA fragment, corresponding to a mass detection limit of ∼2 fg for the 603 base pair fragment. Single λ-DNA molecules intercalated with YOYO-1 at a base pair-to-dye ratio of 10:1 could be detected with an uncomplicated laser-induced fluorescence detection setup. High single-molecule detection efficiency (>50%) was achieved under electrophoretically controlled mass transport conditions in PDMS microchannels
Integrated Capillary Electrophoresis on Flexible Silicone Microdevices: Analysis of DNA Restriction Fragments and Detection of Single DNA Molecules on Microchips
Effect of nitrogen atom positioning on the trade-off between emissive and photocatalytic properties of carbon dots
Carbon dots are an emergent class of nanomaterials that hold promise for innovations in imaging, sensing, and catalytic technologies. Here, Stolarczyk and colleagues control the nitrogen-atom content and location within carbon dots, reporting the resulting impact on emissivity and photocatalytic behaviour