Desarrollo, aprendizaje y ense??anza en la educaci??n secundaria

Resumen basado en el de la publicaci??n

Desarrollando una P2pedagog??a art??stica : propuesta educativa horizontal desde una pedagog??a cr??tica art??stica y medi??tica : desarrollo de proyecto web documental basado en relaciones pedag??gicas P2P

Resumen basado en el de la publicaci??n

Relaciones del Arte de Internet con la Cultura Libre

Resumen basado en el de la publicaci??n

Surface properties of eucalyptus pulp fibres as reinforcement of cement-based composites

The objective of the present work is to evaluate the effects of the surface properties of unrefined eucalyptus pulp fibres concerning their performance in cement-based composites. The influence of the fibre surface on the microstructure of fibre-cement composites was evaluated after accelerated ageing cycles, which simulate natural weathering. The surface of unbleached pulp is a thin layer that is rich in cellulose, lignin, hemicelluloses, and extractives. Such a layer acts as a physical and chemical barrier to the penetration of low molecular components of cement. The unbleached fibres are less hydrophilic than the bleached ones. Bleaching removes the amorphous lignin and extractives from the surface and renders it more permeable to liquids. Atomic force microscopy (AFM) helps in understanding the fibre-cement interface. Bleaching improved the fibre- cement interfacial bonding, whereas fibres in the unbleached pulp were less susceptible to the re-precipitation of cement hydration products into the fibre cavities (lumens). Therefore, unbleached fibres can improve the long-term performance of the fibre-cement composite owing to their delayed mineralization.

Effect of incorporation of 2-tert-butylaminoethyl methacrylate on flexural strength of a denture base acrylic resin

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Chemical characterization and flexural strength of a denture base acrylic resin with monomer 2-tert-butylaminoethyl methacrylate

Purpose: The objectives of this study were to investigate the flexural strength (FS) and chemical interaction between 2-tert-butylaminoethyl methacrylate (TBAEMA) and a denture base acrylic resin. Materials and Methods: Specimens were divided into five groups according to the concentration of TBAEMA incorporated in acrylic resin Onda-Cryl (0%, 1%, 2%, 3%, 4%) and were submitted to Fourier transform infrared spectroscopy (FTIR), electron spectroscopy for chemical analysis (XPS-ESCA), and differential scanning calorimetry (DSC) analyses. FS of the specimens was tested, and results were analyzed by ANOVA/Tukey's test (α < 0.05). Results: Different nitrogen ratios were observed on specimens' surfaces: 0.36%, 0.54%, 0.35%, and 0.20% for groups 1%, 2%, 3%, and 4%, respectively. FTIR indicated copolymerization of acrylic resin and TBAEMA, and DSC results demonstrated a decrease in glass transition temperature (Tg). Significant differences were found for FS (p < 0.05). The mean values were 91.1 ± 5.5,A 77.0 ± 13.1,B 67.2 ± 12.5,B 64.4 ± 13.0,B and 67.2 ± 5.9B MPa for groups 0%, 1%, 2%, 3% and 4%, respectively (same superscript letters indicate no significant difference). Conclusions: The incorporation of TBAEMA in acrylic resin resulted in copolymerization and the presence of amine groups on specimens' surfaces, and in decreases of Tg and FS. © 2012 by the American College of Prosthodontists.

Incorporação de um metacrilato com ação antimicrobiana em uma resina acrílica para base protética: caracterizaçãp Química e efeito sobre resistência flexural e temperatura de transição vítrea

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Incorporação do metacrilato 2-tert-butilaminoetil a uma resina acrílica para a base protética: caracterização química e efeito sobre a resistência flexural

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Caracterização química e resistência à flexão de uma resina acrílica após a incorporação de um polímero com atividade antimicrobiana

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Direct measurement of hydrogen bonding in DNA nucleotide bases by atomic force microscopy.

We have used self-assembled purines and pyrimidines on planar gold surfaces and on gold-coated atomic force microscope (AFM) tips to directly probe intermolecular hydrogen bonds. Electron spectroscopy for chemical analysis (ESCA) and thermal programmed desorption (TPD) measurements of the molecular layers suggested monolayer coverage and a desorption energy of about 25 kcal/mol. Experiments were performed under water, with all four DNA bases immobilized on AFM tips and flat surfaces. Directional hydrogen-bonding interaction between the tip molecules and the surface molecules could be measured only when opposite base-pair coatings were used. The directional interactions were inhibited by excess nucleotide base in solution. Nondirectional van der Waals forces were present in all other cases. Forces as low as two interacting base pairs have been measured. With coated AFM tips, surface chemistry-sensitive recognition atomic force microscopy can be performed.

Distribution of melamine in polyester-melamine surface coatings cured under nonisothermal conditions

The influence of experimental cure parameters on the diffusion of reactive species in polyester-melamine thermoset coatings during curing has been investigated with X-ray photoelectron spectroscopy and attenuated total reflectance Fourier transform infrared. The diffusion of melamine plays a vital role in the curing process and, therefore, in the ultimate properties of coatings. At a low (

Qualitätssicherung zwischen Diversifizierung der Hochschulen und Vereinheitlichung von Standards. Beiträge zur 2. AQ Austria Jahrestagung 2014

Die Jahrestagung 2014 der AQ Austria widmete sich einerseits dem Spannungsfeld zunehmender Diversifizierung von Hochschulen und standardisierten Qualitätssicherungsverfahren andererseits. Im vorliegenden Jahrestagungsband finden sich neben dem Hauptvortrag des Basler Universitätsrektors Loprieno über die Herausforderungen der Diversifizierung für Qualität sowie der Qualitätskultur an Hochschulen auch internationale Beiträge als Antwort aus der Sicht von Qualitätssicherungsagenturen auf die Diversifizierung. Weitere Artikel zu Themen wie duale Studiengänge, Studierbarkeit, Berufungsverfahren sowie Forschungskultur und Qualitätskultur runden die Diskussion über Qualitätssicherung und Diversifizierung in der vorliegenden Publikation ab. Mit Beiträgen von: Loprieno, Antonio; Hanft, Anke; Pichl, Elmar; Jackson, Stephen; Lund, Øystein; Cox, Jeremy; Fink, Kerstin; Brandstätter, Ursula; Bischof, Horst; Gaberscik, Gerald; Janger, Jürgen; Kastner, Johann; Steiger, Anna; Wilhelm, Elena; Holzinger, Helmut; Esca-Scheuringer, Heidi; Kecht, Maria-Regina; Schulmeister, Rolf; Haas, Johannes.

INCORPORACIÓN EFECTIVA DE LA CUENCA HIDROGRÁFICA EN LA PLANIFICACIÓN LOCAL DEL USO DE LA TIERRA

El otorgamiento de  la viabilidad ambiental al Plan Regulador de Escazú, mediante  la resolución No.2308-2008-SETENA, establece importantes tareas a ser resueltas por la Municipalidad de ese Cantón en los próximos cinco años, relacionadas estas con la recuperación de zonas de bosque en toda  la cuenca del río Agres y en particular dentro de  la Zona Protectora de  los Cerros de Esca-zú. Además, la misma resolución de viabilidad ambiental establece la necesidad de considerar la “cuenca hidrográfca” como  la unidad de planifcación ambiental  territorial que debe ser  tomada en cuenta por la Municipalidad de Escazú para la planifcación del desarrollo de su territorio. Por tanto, surge la necesidad de que todas las dependencias de la Municipalidad de Escazú puedan refe-rirse a una nomenclatura estándar de cuencas en el cantón, que ordene la gestión administrativa de los proyectos y obras, razón por la cual el Subproceso de Plan Regulador se enfocó en desarrollar el documento que a continuación se presenta.

L'armonia della natura. Ruolo della musica e degli ultrasuoni nella viticoltura.

Questo elaborato ha come obiettivo quello di illustrare l'utilizzo della musica e degli ultrasuoni nella viticoltura come tecnica innovativa di prevenzione delle avversità della vite, quali patogeni, insetti, malattie, e altri fattori ambientali sfavorevoli come la siccità. In particolare, viene sviluppato il loro impiego contro il vettore della flavescenza dorata, lo Scaphoideus titanus, e nei confronti della specie Homalodisca vitripennis, vettore del batterio Xylella fastidiosa, il quale è responsabile della malattia di Pierce. Viene anche esposto l'uso della Protéodie all'interno dei vigneti e delle cantine francesi, dove queste “melodie delle proteine” agiscono sulla biosintesi proteica delle piante, amplificando la resistenza delle viti nei confronti del mal dell’esca.