2,414 research outputs found
Electronic Structure of the YH3 Phase from Angle-Resolved Photoemission Spectroscopy
Yttrium can be loaded with hydrogen up to high concentrations causing
dramatic structural and electronic changes of the host lattice. We report on
angle-resolved photoemission experiments of the Y trihydride phase. Most
importantly, we find the absence of metal d-bands at the Fermi level and a set
of flat, H-induced bands located at much higher binding energy than predicted,
indicating an increased electron affinity at H sites
A European spine registry
Abstract.: New joint replacement registries are being widely implemented across national and international organizations. The need for a continuous long-term post-market surveillance of implants has been recognized, and has become increasingly important to ensure the quality of prosthetic components. Registry data with large case numbers represent an acceptable alternative to controlled randomized clinical trials, which are often difficult to conduct in orthopedic surgery. The variety of implants and procedures in spinal surgery not only induces the same need for long-term monitoring of post-surgical product performance as in the joint replacement subspecialties, but also renders essential the establishment of a comprehensive spine registry for all major pathologies and interventions. In cooperation with the M.E. MĂĽller Institute for Evaluative Research in Orthopedic Surgery (MEM-CED) at the University of Berne, Switzerland, the Spine Society of Europe (SSE) has launched Spine Tango: the first modular and multilevel European online registry for spinal surgery. Within Spine Tango, the major challenge in registry design and structure is the definition of and agreement upon a core set of questions as a common European dataset. Additional questions for national or individual interest can also be dynamically added to the core dataset. An automated implant tracking system has also been setup, which allows highly precise product documentation without additional work for clinical staff member
A randomized crossover trial assessing patient preference for two different types of portable infusion-pump devices
Background: A variety of anticancer agents are better tolerated and more effective if given as continuous compared to bolus administration. Portable pump devices are needed to allow outpatient continuous infusion. Different types of portable pumps are available and we tested patient preference in a randomized crossover design. Patients and methods: Patients on continuous infusion fluorouracil were randomly assigned to start treatment with an elastomeric infusor (Baxter) or a mechanical, electronically controlled pump (CADD-1™, Pharmacia) and crossed over to the alternative model after three weeks. After exposure to both pump types patients were asked to indicate their preferred device. Results: After 10 patients the study was closed because all study participants preferred the elastomeric pump (P < 0.01). Reasons were pump weight (100%), smaller pump size (89%), interference with daily activities (89%), user friendliness (56%), impact on sleep (44%), and lack of technical problems (22%). Although the mechanical pump required more handling time for the first two refillings, the learning curve suggested about equal time requirement thereafter. Conclusion: In the interest of patient comfort, the disposable elastomeric infusor is an acceptable alternative to the more accurate electronically controlled pumps especially for drugs with a short half-life and a favorable toxicity profil
SSE Spine Tango - content, workflow, set-up: www.eurospine.org - Spine Tango
The Spine Tango registry is now accessible via the SSE webpage under www.eurospine.org - Spine Tango. Links to the Swiss/International, German and Austrian modules are provided as well as information about the philosophy, methodology and content. Following the links, the users are taken to the respective national modules for registration or log-in and data entry. The Swiss/International module, also accessible under www.spinetango.com, is used by all Swiss and international users, who do not have a separate national module. The physician administered forms for surgery, staged surgery and follow-up can be downloaded as PDFs.The officially recommended Spine Tango patient forms are also available. All forms were implemented in an online version and as scannable optical mark reader forms which can be ordered from the corresponding autho
Benchmarking with Spine Tango: potentials and pitfalls
The newly released online statistics function of Spine Tango allows comparison of own data against the aggregated results of the data pool that all other participants generate. This comparison can be considered a very simple way of benchmarking, which means that the quality of what one organization does is compared with other similar organizations. The goal is to make changes towards better practice if benchmarking shows inferior results compared with the pool. There are, however, pitfalls in this simplified way of comparing data that can result in confounding. This means that important influential factors can make results appear better or worse than they are in reality and these factors can only be identified and neutralized in a multiple regression analysis performed by a statistical expert. Comparing input variables, confounding is less of a problem than comparing outcome variables. Therefore, the potentials and limitations of automated online comparisons need to be considered when interpreting the results of the benchmarking procedur
Doping nature of native defects in 1T-TiSe2
The transition metal dichalcogenide 1T-TiSe2 is a quasi two-dimensional
layered material with a charge density wave (CDW) transition temperature of
TCDW 200 K. Self-doping effects for crystals grown at different temperatures
introduce structural defects, modify the temperature dependent resistivity and
strongly perturbate the CDW phase. Here we study the structural and doping
nature of such native defects combining scanning tunneling
microscopy/spectroscopy and ab initio calculations. The dominant native single
atom dopants we identify in our single crystals are intercalated Ti atoms, Se
vacancies and Se substitutions by residual iodine and oxygen.Comment: 5 pages, 3 figure
STM microscopy of the CDW in 1T-TiSe2 in the presence of single atom defects
We present a detailed low temperature scanning tunneling microscopy study of
the commensurate charge density wave (CDW) in 1-TiSe in the presence of
single atom defects. We find no significant modification of the CDW lattice in
single crystals with native defects concentrations where some bulk probes
already measure substantial reductions in the CDW phase transition signature.
Systematic analysis of STM micrographs combined with density functional theory
modelling of atomic defect patterns indicate that the observed CDW modulation
lies in the Se surface layer. The defect patterns clearly show there are no
2-polytype inclusions in the CDW phase, as previously found at room
temperature [Titov A.N. et al, Phys. Sol. State 53, 1073 (2011). They further
provide an alternative explanation for the chiral Friedel oscillations recently
reported in this compound [J. Ishioka et al., Phys. Rev. B 84, 245125, (2011)].Comment: 5 pages, 4 figure
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