123 research outputs found
The influence of the preparation methods on the inclusion of model drugs in a β-cyclodextrin cavity
NOTICE: this is the author’s version of a work that was accepted for publication in European Journal of Pharmaceutics and Biopharmaceutics. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Eur J Pharm Biopharm. 2009 Feb;71(2):377-386. Epub 2008 Oct 17.The work aims to prove the complexation of two model drugs (ibuprofen, IB and indomethacin, IN) by bcyclodextrin
(bCD), and the effect of water in such a process, and makes a comparison of their complexation
yields. Two methods were considered: kneading of a binary mixture of the drug, bCD, and inclusion
of either IB or IN in aqueous solutions of bCD. In the latter method water was removed by air stream,
spray-drying and freeze-drying. To prove the formation of complexes in final products, optical microscopy,
UV spectroscopy, IR spectroscopy, DSC, X-ray and NMR were considered. Each powder was added
to an acidic solution (pH = 2) to quantify the concentration of the drug inside bCD cavity. Other media
(pH = 5 and 7) were used to prove the existence of drug not complexed in each powder, as the drugs solubility
increases with the pH. It was observed that complexation occurred in all powders, and that the
fraction of drug inside the bCD did not depend neither on the method of complexation nor on the
processes of drying considered
Media in the Spanish autonomous community of Galicia. The process of desgalleguización of media
This article is about the microsystem of media in the autonomous community of Galicia in Spain. The first part provides a brief historical overview of the political transformation in Spain after 1975 and its impact on regional development. Further on, the role of the mainstream media in the region of Galicia is analyzed: the press (La Voz de Galicia, Xornal de Galicia), radio (Radio Galega) and television (TVG). The last part focuses on the process of desgalleguización, which has been taking place in Galicia since the mid-1990s, and which has adversely affected the status of the Galego language in public spaces. It turns out that Galicia has not been able to use the tools, its autonomous governments has been equipped with to merge the region and to develop linguistic and cultural identity of its inhabitants
Die vaskuläre Anatomie der vorderen Bauchwand: ein Beitrag zur Vermeidung von Gefäßverletzungen bei der laparoskopischen Chirurgie
Die Verletzung der in der Bauchwand verlaufenden Gefäße ist eine potentielle Komplikation aller laparoskopischer Verfahren. Die Kenntnis der Anatomie bildet die Grundvoraussetzung zur Vermeidung derartiger Komplikationen. An 28 Leichnamen wurde der Verlauf der Gefäße der Bauchwand bestimmt und Regionen für eine sichere sowie solche für eine gefährliche Trokarposition (dangerous zones) aufgezeigt.Injuries to vessels of the abdominal wall are an potential complication in laparoscopic surgery but, with the increasing use of this technique, tend to occur more often. The exact knowledge of the anatomy of the parietal structures of the abdominal wall remains the main prerequisite in avoiding these complications. In this study, the course of these vessels was dissected in 28 abdominal walls taken from human cadavers, and regions for relatively safe trocar positions and ‘dangerous zones’ were determined
Influence of Alumina Addition on the Optical Properties and the Thermal Stability of Titania Thin Films and Inverse Opals Produced by Atomic Layer Deposition
TiO2 thin films deposited by atomic layer deposition (ALD) at low temperatures (<100 °C) are, in general, amorphous and exhibit a smaller refractive index in comparison to their crystalline counterparts. Nonetheless, low-temperature ALD is needed when the substrates or templates are based on polymeric materials, as the deposition has to be performed below their glass transition or melting temperatures. This is the case for photonic crystals generated via ALD infiltration of self-assembled polystyrene templates. When heated up, crystal phase transformations take place in the thin films or photonic structures, and the accompanying volume reduction as well as the burn-out of residual impurities can lead to mechanical instability. The introduction of cation doping (e.g., Al or Nb) in bulk TiO2 parts is known to alter phase transitions and to stabilize crystalline phases. In this work, we have developed low-temperature ALD super-cycles to introduce Al2O3 into TiO2 thin films and photonic crystals. The aluminum oxide content was adjusted by varying the TiO2:Al2O3 internal loop ratio within the ALD super-cycle. Both thin films and inverse opal photonic crystal structures were subjected to thermal treatments ranging from 200 to 1200 °C and were characterized by in- and ex-situ X-ray diffraction, spectroscopic ellipsometry, and spectroscopic reflectance measurements. The results show that the introduction of alumina affects the crystallization and phase transition temperatures of titania as well as the optical properties of the inverse opal photonic crystals (iPhC). The thermal stability of the titania iPhCs was increased by the alumina introduction, maintaining their photonic bandgap even after heat treatment at 900 °C and outperforming the pure titania, with the best results being achieved with the super-cycles corresponding to an estimated alumina content of 26 wt.%
Conventional Study on Novel Dicationic Ionic Liquid Inclusion with β-Cyclodextrin
This study focuses on the synthesis and characterization of the inclusion complex of β-Cyclodextrin (β-CD) with dicationic ionic liquid, 3,3′-(1,4-Phenylenebis [methylene]) bis(1-methyl-1H-imidazol-3-ium) di(bromide) (PhenmimBr). The inclusion complex was prepared at room temperature utilizing conventional kneading technique. Proton (1H) NMR and 2D (1H–1H) COSY NMR were the primary characterization tools employed to verify the formation of the inclusion complex. COSY spectra showed strong correlations between protons of imidazolium and protons of β-CD which indicates that the imidazolium ring of PhenmimBr has entered the cavity of β-CD. UV absorption indicated that β-CD reacts with PhenmimBr to form a 2:1 β-CD-PhenmimBr complex with an apparent formation constant of 2.61 × 105 mol&−2 L2. Other characterization studies such as UV, FT-IR, XRD, TGA, DSC and SEM studies were also used to further support the formation of the β-CD-PhenmimBr inclusion complex
States' readiness to participate in military humanitarian intervention in Libya in 2011. : analysis in the light of international relations' theories
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