Bulk metallic glasses (BMGs) are a class of amorphous metals that exhibit high strength, ductility paired with wear and corrosion resistance. These properties suggest that they could serve as an alternative to conventional metallic implants that suffer wear and failure. In the present study, we investigated Platinum (Pt)-BMG biocompatibility in bone applications. Specifically, we investigated osteoclast formation on flat and nanopatterned Pt57.5Cu14.7Ni5.3P22.5 (atomic percent) as well as titanium (control). Specifically, receptor activator of NF-κB (RANK) ligand-induced murine bone marrow derived mononuclear cell fusion was measured on multiple nanopatterns and was found to be reduced on nanorods (80 and 200 nm in diameter) and was associated with reduced tartrate-resistant acid phosphatase (TRAP) and matrix metalloproteinase (MMP9) expression. Evaluation of mesenchymal stem cell (MSC) to osteoblast differentiation on nanopatterned Pt-BMG showed significant reduction in comparison to flat, suggesting that further exploration of nanopatterns is required to have simultaneous induction of osteoblasts and inhibition of osteoclasts.In vivo studies were also pursued to evaluate the biocompatibility of Pt-BMG in comparison to titanium. Rods of each material were implanted in the femurs of mice and evaluated by x-ray, mechanical testing, micro-computed tomography (micro-CT), and histological analysis. Overall, Pt-BMG showed similar biocompatibility with titanium suggesting that it has the potential to improve outcomes by further processing at the nanoscale.

Cómo citar este artículo: GARCÍA, R., HERRERA, R. y SOTO, J. Dispersión del comportamiento energético residencial; revisión de viviendas en el Centro-Sur de Chile [en línea] Fecha de consulta: dd-mm-aa. En: ACE: Architecture, City and Environment = Arquitectura, Ciudad y Entorno, 8 (23): 165-192, 2013.

Chagas disease (CD) caused by the parasite Trypanosoma cruzi, belongs to the so-called neglected diseases group. In Argentina about 1,500 children are born with congenital Chagas disease per year. The diagnosis of CD in the newborn relies on the ability to detect parasites in the blood by microscopic observation, as the serological tests are ruled out because of the presence of maternal antibodies. CD treatment is more effective during the acute phase of infection. Early diagnosis and treatment of the disease is thus very important. The Argentinian National Program for early detection of metabolic diseases uses Whatman903 filter paper for blood sampling. This type of sample collection presents many advantages as the use of low blood volumes, minimal biological risk, and easy storage and transportation. The objective of the study was to evaluate the conservation efficiency of blood samples on filter paper in order to access good sensitivity on qPCR results for the detection of T. cruzi. To standardize the procedure, negative samples of blood were infected artificially with serial dilutions of trypomastigotes forms of T. cruzi from the TcVI strain obtained by cell culture in Vero cells. Concentrations between 50000 and 5 parasites/mL were prepared and loaded in filter paper for analysis. DNA extraction was conducted by the QIAamp DNA Mini Kit from QIAGEN. For qPCR, a method based on TaqMan technology was used, with a multiplex reaction for quantification of T. cruzi satellite DNA and an internal amplification control (IAC). The detection limit found from our results was 400 parasites/mL, demonstrating that this method could be a reliable option for the diagnosis of congenital CD by the detection of T. cruzi in blood collected in filter paper.

En Chile, tal como ocurre a nivel global, el patrimonio industrial presenta dispares grados de valoración. Antiguos barrios industriales en ciudades intermedias se debaten entre la “ruinificación” y el redesarrollo de su legado construido. Este problema ha cobrado notoriedad en las últimas décadas, gracias a una ciudadanía cada vez más movilizada por la defensa patrimonial; y frente a la cual los actores públicos y privados han respondido reactivamente. A partir del caso del barrio textil de Bellavista, el objetivo de esta investigación es estudiar la interacción, agendas y capacidad de incidencia de diversos tipos de actores en procesos de patrimonialización, así como las estrategias utilizadas en particular por los actores sociales para superar las asimetrías de poder. El análisis de discurso y de redes arrojó una poderosa evidencia con respecto a la organización de los actores en comunidades intersectoriales y multiescalares, las que se articulan a su vez en torno a actores claves. Se verifica la importancia de estos vínculos para alterar las asimetrías de poder, así como el potencial articulador del gobierno local; empero, esto está fuertemente limitado por su ambivalente trayectoria y la consecuente desconfianza de los movimientos sociales.

Resumen: No sin conflicto, los procesos contemporáneos de patrimonialización en Chile muestran un desplazamiento desde la perspectiva tradicional -funcional al discurso de Estado nación y del mercado-hacia planteamientos más complejos e inclusivos. Esta tendencia exige de los agentes involucrados importantes capacidades de negociación, a la vez que voluntad política para transitar hacia una co-construcción del patrimonio. A partir del análisis de discursos de entrevistas en profundidad, trianguladas con datos secundarios, analizamos el proceso de declaratoria de la Fábrica Bellavista Oveja Tomé, en la ciudad de Tomé, como Monumento Histórico; un edificio de propiedad privada e ícono para la comunidad local. Los resultados del análisis del material indican que las alteridades que alcanzan sus objetivos son aquellas que han logrado desarrollar un activismo complejo, que utiliza tanto formas institucionales como 'no institucionales' de acción y, sobre todo, que regula los niveles de presión que impulsa, de manera de no quebrar la mesa de negociaciones, pero que a la vez logra alterar las perspectivas hegemónicas 'oficializando' el patrimonio 'no oficial' .Palabras clave: Construcción social del patrimonio, agentes patrimoniales, activación patrimonial,