Facile sol-gel synthesis of porous silicas using poly(propylene)imine dendrimers as templates

Commercially available poly(propylene)imine (DAB-Am-32 and DAB-Am-64) dendrimers were used as single-molecule templates to tailor the porosity of silicas via a nonacidic sol-gel method. X-ray diffraction on both the as-prepared (oven-dried at 373 K) and the calcined (833 K) materials revealed that modest contraction took place on template removal and that the cavities created did not achieve three-dimensional ordering under the current synthesis conditions. Transmission electron microscopy of “Pt-stained” samples supported this picture. A modified Horvath–Kawazoe analysis of the argon adsorption isotherms indicated that DAB-Am-64 is a much more effective template than DAB-Am-32. Pyrolysis and oxidation protocols for template removal are also presented

Facile sol-gel synthesis of porous silicas using poly(propylene)imine dendrimers as templates

Commercially available poly(propylene)imine (DAB-Am-32 and DAB-Am-64) dendrimers were used as single-molecule templates to tailor the porosity of silicas via a nonacidic sol-gel method. X-ray diffraction on both the as-prepared (oven-dried at 373 K) and the calcined (833 K) materials revealed that modest contraction took place on template removal and that the cavities created did not achieve three-dimensional ordering under the current synthesis conditions. Transmission electron microscopy of “Pt-stained” samples supported this picture. A modified Horvath–Kawazoe analysis of the argon adsorption isotherms indicated that DAB-Am-64 is a much more effective template than DAB-Am-32. Pyrolysis and oxidation protocols for template removal are also presented

Surgimiento de las escuelas de educación estética en la provincia de Buenos Aires

Existen hoy en la Provincia de Buenos Aires 68 Escuelas de Educación Estética, que dependen de la Dirección General de Escuelas. Son espacios que posibilitan la experimentación y el aprendizaje a través de diferentes lenguajes artísticos, que se estructuran para que los alumnos asistan a contra turno de las escuelas primarias. Producto de inquietudes y esfuerzos personales e institucionales, sus raíces se generan en dos distritos diferentes, con modalidades que no son idénticas. En este trabajo, que tiene por objeto comenzar a rescatar la historia de sus orígenes, se analiza la importancia que otras instituciones educativas, el IDOEI y el Gabinete de Estética, tuvieron como antecedentes de estas escuelas.Eje 11: Las corrientes pedagógicas y sus correlatos en la educación artística.Facultad de Bellas Arte

Surgimiento de las escuelas de educación estética en la provincia de Buenos Aires

Existen hoy en la Provincia de Buenos Aires 68 Escuelas de Educación Estética, que dependen de la Dirección General de Escuelas. Son espacios que posibilitan la experimentación y el aprendizaje a través de diferentes lenguajes artísticos, que se estructuran para que los alumnos asistan a contra turno de las escuelas primarias. Producto de inquietudes y esfuerzos personales e institucionales, sus raíces se generan en dos distritos diferentes, con modalidades que no son idénticas. En este trabajo, que tiene por objeto comenzar a rescatar la historia de sus orígenes, se analiza la importancia que otras instituciones educativas, el IDOEI y el Gabinete de Estética, tuvieron como antecedentes de estas escuelas.Eje 11: Las corrientes pedagógicas y sus correlatos en la educación artística.Facultad de Bellas Arte

Surgimiento de las escuelas de educación estética en la provincia de Buenos Aires

Existen hoy en la Provincia de Buenos Aires 68 Escuelas de Educación Estética, que dependen de la Dirección General de Escuelas. Son espacios que posibilitan la experimentación y el aprendizaje a través de diferentes lenguajes artísticos, que se estructuran para que los alumnos asistan a contra turno de las escuelas primarias. Producto de inquietudes y esfuerzos personales e institucionales, sus raíces se generan en dos distritos diferentes, con modalidades que no son idénticas. En este trabajo, que tiene por objeto comenzar a rescatar la historia de sus orígenes, se analiza la importancia que otras instituciones educativas, el IDOEI y el Gabinete de Estética, tuvieron como antecedentes de estas escuelas.Eje 11: Las corrientes pedagógicas y sus correlatos en la educación artística.Facultad de Bellas Arte

Preparation and evaluation of the electrospun chitosan/PEO fibers for potential applications in cartilage tissue engineering

Fibrous materials have morphological similarities to natural cartilage extracellular matrix and have been considered as candidate for bone tissue engineering scaffolds. In this study, we have evaluated a novel electrospun chitosan mat composed of oriented sub-micron fibers for its tensile property and biocompatibility with chondrocytes (cell attachment, proliferation and viability). Scanning electronic microscope images showed the fibers in the electrospun chitosan mats were indeed aligned and there was a slight cross-linking between the parent fibers. The electrospun mats have significantly higher elastic modulus (2.25 MPa) than the cast films (1.19 MPa). Viability of cells on the electrospun mat was 69% of the cells on tissue-culture polystyrene (TCP control) after three days in culture, which was slightly higher than that on the cast films (63% of the TCP control). Cells on the electrospun mat grew slowly the first week but the growth rate increased after that. By day 10, cell number on the electrospun mat was almost 82% that of TCP control, which was higher than that of cast films (56% of TCP). The electrospun chitosan mats have a higher Young’s modulus (P \u3c0.01) than cast films and provide good chondrocyte biocompatibility. The electrospun chitosan mats, thus, have the potential to be further processed into three-dimensional scaffolds for cartilage tissue repair

Preparation and evaluation of the electrospun chitosan/PEO fibers for potential applications in cartilage tissue engineering

Fibrous materials have morphological similarities to natural cartilage extracellular matrix and have been considered as candidate for bone tissue engineering scaffolds. In this study, we have evaluated a novel electrospun chitosan mat composed of oriented sub-micron fibers for its tensile property and biocompatibility with chondrocytes (cell attachment, proliferation and viability). Scanning electronic microscope images showed the fibers in the electrospun chitosan mats were indeed aligned and there was a slight cross-linking between the parent fibers. The electrospun mats have significantly higher elastic modulus (2.25 MPa) than the cast films (1.19 MPa). Viability of cells on the electrospun mat was 69% of the cells on tissue-culture polystyrene (TCP control) after three days in culture, which was slightly higher than that on the cast films (63% of the TCP control). Cells on the electrospun mat grew slowly the first week but the growth rate increased after that. By day 10, cell number on the electrospun mat was almost 82% that of TCP control, which was higher than that of cast films (56% of TCP). The electrospun chitosan mats have a higher Young’s modulus (P \u3c0.01) than cast films and provide good chondrocyte biocompatibility. The electrospun chitosan mats, thus, have the potential to be further processed into three-dimensional scaffolds for cartilage tissue repair

Impact of climate change on energy use and bioclimatic design of residential buildings in the 21st century in Argentina

Climate change will have great impacts on building´ energy consumption and design of future buildings should consider this situation. The aims of this research are to evaluate the impact of climate change on the energy performance of residential buildings and to analyze if bioclimatic strategies that are appropriate for present climatic conditions should be applied in the design of future buildings. A compact conventional housing that represents an Argentinean typical mid-income house was simulated with EnergyPlus software and calibrated with measured data. Energy consumption and bioclimatic strategies were analyzed for future data under A2 scenario. The change of annual energy use between the baseline period (1961-1990) and 2080 is predicted to range from − 25% to 8% for conventional housing buildings. The energy destined to air heating and cooling will be 23%?59% lower and 360-790% higher, respectively, in 2080 than in the baseline period (1961-1990). These values correspond to decreases between 6.0 and 7.6 kWh/m2-decade (heating) and increases between 1.7 and 8.4 kWh/m2-decade (cooling). Recommendations on future building design and building retrofit are done. Sunshading together a with reduction of direct solar gains and natural ventilation were found to be the most effective design strategies to counteract climate changes in future buildings.Fil: Flores Larsen, Silvana Elinor. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones en Energía no Convencional. Universidad Nacional de Salta. Facultad de Ciencias Exactas. Departamento de Física. Instituto de Investigaciones en Energía no Convencional; ArgentinaFil: Filippin, Maria Celina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Barea Paci, Gustavo Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Ambiente, Hábitat y Energía; Argentin