			Home About us Contact

Original Material (original + material)

Distribution by Scientific Domains

Polymers and Materials Science	50%

Selected Abstracts

Effect of thermal exposure on the microstructure, tensile properties and the corrosion behaviour of 6061 aluminium alloy sheet

MATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 4 2005
R. Braun
See original Materials and Corrosion 2005, 56, No. 3, p. 159,165 (2005) [source]

Membranes of cellulose triacetate produced from sugarcane bagasse cellulose as alternative matrices for doxycycline incorporation

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2009
Guimes Rodrigues Filho
Abstract Cellulose triacetate (CTA) membranes were prepared using polyethylene glycol, 600 g mol,1, (PEG) as additive and were utilized in essays of doxycycline (DOX) incorporation using two different procedures: (i) incorporation of the drug during the membrane preparation and (ii) incorporation of the drug to a previously prepared membrane. In the first, the produced membrane presented high compatibility between DOX and CTA, what was evidenced by analyzing the DSC curve for a CTA/PEG 50%/DOX system. Results showed that the drug is homogeneously distributed throughout the matrix, molecularly. In the second method, the drug was molecularly and superficially adsorbed, as seen through the DSC curve for the system CTA/PEG 10%/DOX, which nearly does not present alterations in relation to the original material, and through the isotherm of drug adsorption that follows the Langmuir model. Results showed that the membranes produced from sugarcane bagasse are adequate to produce matrices for drug-controlled release, both for enteric use (Method (i)) and topic use (Method (ii)). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 [source]

CHEMICAL AND PHYSICAL CHARACTERIZATION OF STUCCOS FROM A MEXICAN COLONIAL BUILDING: EL MUSEO DEL CALENDARIO OF QUERETARO*

ARCHAEOMETRY, Issue 5 2009
MIGUEL GALVÁN-RUIZ
Restoration requires the use of appropriate characterization methods and suitable new material preparation processes permit the reproduction of the original material to be as similar as possible in order to be an appropriate application method. The combination of these factors will facilitate a good restoration process. Different stuccos were taken from El Museo del Calendario, a building located in Querétaro, Mexico which was built in the 16th century. All the stucco samples were studied using the characterization process which is proposed in this article. The characterization method consisted of the use of analytical techniques, such as X-ray diffraction, Fourier transform infrared and scanning electron microscopy. This characterization method made reproduction of the original material possible. The new material combined with new application techniques developed in situ will result in a high-quality restoration process. [source]

Comparative assessment of S. aureus microbial biofilm inhibition by an N-alkyl-polyethyleneimine covalently attached to PMMA or titanium in the Boston Keratoprosthesis

ACTA OPHTHALMOLOGICA, Issue 2009
I BEHLAU
Purpose Biofilms are matrix-associated microbial communities adherent to either biological surfaces or abiotic surfaces. They account for the majority of device-associated infections. Our goal herein is to minimize bacterial adherence and biofilm formation by comparative analysis of new polycations bound to bio-prosthetic ocular-associated materials, poly (methyl methacrylate) (PMMA) or titanium, using the Boston KPro as a model system. Methods Using S.aureus ocular-associated clinical isolates, a quantitative assessment of microbial biofilm formation by linear N,N-dodecyl,methyl-polyethyleneimine (DMPEI) (217 kDa) covalently bound to PMMA or titanium compared to the parent PMMA or Ti, respectively, has been performed using confocal laser scanning and electron microscopies. In addition, DMPEI-bound materials have been screened for corneal toxicity in both cell tissue culture and rodent models, and as compared to the original materials. Results A marked inhibitory effect in S. aureus biofilm formation on DMPEI-derivatized materials compared to the parent PMMA (3-4 fold) and Ti (2-fold), without conferring additional epithelial cell cytotoxicity in vitro, has been observed. Furthermore, we have found no additional tissue reactivity, and possibly even a protective effect, with DMPEI-derivatized materials in vivo. Conclusion We found that covalent derivatization with DMPEI of PMMA and Ti greatly reduces S. aureus biofilm formation in vitro compared to the parent materials. There was no additional cytotoxicity seen both in vitro and in vivo. Future studies will evaluate DMPEI-derivatized materials for in vivo antimicrobial efficacy. [source]