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991.
992.
The influence of truly three‐dimensional microstructures on osteoblast‐like cells is reported. Well defined templates are fabricated by direct laser writing and biocompatibly coated with titanium dioxide, resembling implant surfaces. The influence of structural parameters on proliferation, morphology, adhesion, and differentiation is studied. A significantly higher proliferation (170%) is observed on particular topographies compared to unstructured surfaces. Additionally, an influence of structural parameters on the morphology of osteoblast‐like cells is obtained, whereas all cells possess the osteoblastic marker alkaline phosphatase within all structures. 相似文献
993.
Schwarz R Huttner B Döllinger M Luegmair G Eysholdt U Schuster M Lohscheller J Gurlek E 《IEEE transactions on bio-medical engineering》2011,58(10):2767-2776
After total larynx excision due to laryngeal cancer, the tracheoesophageal substitute tissue vibrations at the intersection between the pharynx and the esophagus [pharyngoesophageal segment (PE segment)] serve as voice generator. The quality of the substitute voice significantly depends on the vibratory characteristics of the PE segment. For improving voice rehabilitation, the relationship between the PE dynamics and the resulting substitute voice quality is a matter of particular interest. Precondition for a comprehensive analysis of this relationship is an objective quantification of the PE vibrations. For quantification purposes, a method is proposed, which is based on the reproduction of the tissue vibrations by means of a biomechanical model of the PE segment. An optimization procedure for an automatic determination of appropriate model parameters is suggested to adapt the model dynamics to tissue movements extracted from high-speed (HS) videos. The applicability of the optimization procedure is evaluated with ten synthetic data sets. A mean error of 8.2% for the determination of previously defined model parameters was achieved as well as an overall stability of 7.1%. The application of the model to six HS recordings presented a mean correlation of the vibration patterns of 82%. 相似文献
994.
Georg R. Meseck Roman Kontic Greta R. Patzke Stefan Seeger 《Advanced functional materials》2012,22(21):4433-4438
Nanoscale TiO2 photocatalysts are key materials for convenient wastewater treatment and other essential cleaning processes. Immobilization of TiO2 nanoparticles (NPs) is thus indispensable for the facile handling and separation of nanocatalysts as well as for minimizing their potential health and environmental hazards. Silicone nanofilaments are introduced as a new flexible carrier type for titania NPs because they are compatible with a wide range of substrates and they display high chemical stability. TiO2‐NPs are deposited on glass slides covered with thin carpets of silicone nanofilaments in a single reaction step starting from TiF4 and optimized ethanol/water ratios. The resulting composites are characterized using a wide range of electron microscopy and other analytical techniques, and their photocatalytic activity in the decomposition of methylene blue (MB) is superior to immobilized TiO2 references on plain substrates. 相似文献
995.
Catherine Marichy Nicola Donato Marc‐Georg Willinger Mariangela Latino Dmitry Karpinsky Seung‐Ho Yu Giovanni Neri Nicola Pinna 《Advanced functional materials》2011,21(4):658-666
A new atomic layer deposition (ALD) process for nanocrystalline tin dioxide films is developed and applied for the coating of nanostructured materials. This approach, which is adapted from non‐hydrolytic sol‐gel chemistry, permits the deposition of SnO2 at temperatures as low as 75 °C. It allows the coating of the inner and outer surface of multiwalled carbon nanotubes with a highly conformal film of controllable thickness. The ALD‐coated tubes are investigated as active components in gas‐sensor devices. Due to the formation of a p‐n heterojunction between the highly conductive support and the SnO2 thin film an enhancement of the gas sensing response is observed. 相似文献
996.
997.
Klaus Altmeyer 《Datenschutz und Datensicherheit - DuD》2007,31(7):502-505
Die BASF AG hat als eines der ersten deutschen Unternehmen mit einer globalen Sensibilisierungskampagne den Umgang der Mitarbeiter
mit sensiblen Informationen erh?ht. Klaus Altmeyer stellt die Kampagne vor und berichtet von seinen Erfahrungen. 相似文献
998.
An enantioselective synthesis of tert-butyl (5S,6R)-(E)-5-tert-butyldimethylsilyloxy-6-methyl-2,7-octadieno ate, a precursor for the synthesis of the antimitotic macrolides cryptophycin A and arenastatin A (cryptophycin-24), is presented. The key step in the reaction sequence features a crotyl boration that sets both stereocenters that become the C16 hydroxyl and Cl' methyl in the cryptophycins. Homologation of the terminal olefin via a Heck reaction is presented. 相似文献
999.
Georg Herdrich Monika Auweter-Kurtz Markus Fertig Anuscheh Nawaz Dejan Petkow 《Vacuum》2006,80(11-12):1167
MHD effects arising in plasma sources, such as short-pulsed magnetoplasmadynamic generators and inductively heated plasma generators, are analyzed with both algebraic models and measured data. Functional principles of the sources based on their MHD behavior are explained. Moreover, Stewart numbers in the order of magnitude of at least 10−1 are calculated for the systems and qualified as an identifier for the magnetic influence on plasmas. Here, the considered plasma systems that are a priori known as MHD systems were used to determine typical values of the Stewart number. Based on this experience the concept of a plasma probe to magnetically influence or control weakly ionized free stream plasma flows is presented. 相似文献
1000.